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PRIORITY CLAIM
The present application claims priority from PCT/US2011/041192, filed 21 Jun. 2011, which claims priority from U.S. provisional application 61/358,199, filed 24 Jun. 2010, which is incorporated herein by reference.
BACKGROUND OF INVENTION
1. Field of the Invention
The invention relates to pipe systems and their methods of use.
2. Background Art
PCT Patent Application WO 2010/17082 discloses printing blankets, pipe liners, conveyor belts, inflatable articles, collapsible containers, protective clothing, and other types of coated fabrics that are manufactured with a thermoplastic block copolymer (TBC). This TBC can be a thermoplastic polyurethane (TPU), a copolyester (COPE), a copolyamide (COPA) or a polyurethaneurea (TPUU). It also a printing blanket or printing sleeve and a cured in place liner for a passageway or pipe. The TBC is (I) the reaction product of (1) a hydrophobic polyol or polyamine, (2) a polyisocyanate or an aromatic dicarboxylic acid, and (3) a linear chain extender containing 2 to 20 carbon atoms, or (II) the reaction product of (1) a hydrophobic polyol or polyamine, and (2) a carboxylic terminated telechelic polyamide sequence. PCT Patent Application WO 2010/17082 is herein incorporated by reference in its entirety.
U.S. Pat. No. 7,485,343 discloses a method for preparing a hydrophobic coating by preparing a precursor sol comprising a metal alkoxide, a solvent, a basic catalyst, a fluoroalkyl compound and water, depositing the precursor sol as a film onto a surface, such as a substrate or a pipe, heating, the film and exposing the film to a hydrophobic silane compound to form a hydrophobic coating with a contact angle greater than approximately 150 degrees. The contact angle of the film can be controlled by exposure to ultraviolet radiation to reduce the contact angle and subsequent exposure to a hydrophobic silane compound to increase the contact angle. U.S. Pat. No. 7,485,343 is herein incorporated by reference in its entirety
U.S. Pat. No. 7,344,783 discloses a hydrophobic coating including solid silsesquioxane silicone resins to increase durability. The hydrophobic coating is any composition that increases the contact angle to a surface, preferably glass. The durability of the hydrophobic coating is preferably increased to one and a half years, more preferably three years. U.S. Pat. No. 7,344,783 is herein incorporated by reference in its entirety.
SUMMARY OF THE INVENTION
One aspect of the invention provides a pipe system comprising a pipe comprising an exterior of the system, the pipe comprising an inner pipe wall; a hydrophobic layer interior to the inner pipe wall or a hydrophobic layer extending from within the pipe wall to the interior to the inner pipe wall; and a fluid-solid stream interior to the hydrophobic layer and interior to the inner pipe wall, the fluid-solid stream comprising water, one or more hydrocarbons, and produced solids.
Advantages of the invention include one or more of the following:
reduced formation of deposits on interior pipe walls, such as hydrates;
transport of produced fluids with significantly reduced deposits;
transport of produced fluids without deposits;
a reduced force required for pigging; and/or
generation of a fluid slurry when pigging.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an example of a self-assembled monolayer in accordance with embodiments disclosed herein.
DETAILED DESCRIPTION
In one aspect, embodiments disclosed herein relate to a system and method for preventing hydrate blockages in conduits. Specifically, some embodiments disclosed herein relate to a pipeline with a hydrophobic inner wall and methods for making the same to prevent hydrate blockage. Other embodiments disclosed herein relate to a pipeline with a hydrate-phobic inner wall and methods for making the same to prevent hydrate blockage.
In another aspect, embodiments disclosed herein relate to a process for reconditioning the inner wall of a conduit to inhibit hydrate formation. Specifically, some embodiments disclosed herein relate to a process for reconditioning a hydrophobic inner wall of a pipeline that includes chemical soaking.
In some embodiments of the present disclosure, the inner wall of a conduit (e.g., a steel tube, pipeline, flowline, etc.) is modified to be hydrophobic or hydrate-phobic to prevent hydrate blockage. Generally, hydrates are crystalline clathrate compounds (i.e., inclusion compounds) formed by hydrocarbons and water under low temperature and high pressure conditions. However, hydrates may also form from non-hydrocarbons, such as carbon dioxide, nitrogen and hydrogen sulfide, under the proper temperature and pressure conditions. The term “hydrocarbon,” as used herein, may include both hydrocarbons and non-hydrocarbons that are used to form hydrates. Hydrocarbons may generally include alkyls, alkenyls, alkynyls, cycloalkyls, aryls, alkaryls, and aralkyls, for example. Specific examples of hydrate-forming hydrocarbons include, but are not limited to, ethylene, acetylene, propylene, methylacetylene, n-butane, isobutene, 1-butene, trans-2-butene, cis-2-butene, isobutene, butane mixtures, isopentane, pentenes, argon, krypton, xenon, and mixtures thereof. The term “hydrocarbon” may also refer to natural gas. Natural gas hydrocarbons may include methane, ethane, propane, butane, nitrogen, oxygen, carbon dioxide, carbon monoxide, hydrogen, and hydrogen sulfide, for example.
Hydrate formation requires the presence of water (even in small amounts), a temperature lower than the hydrate formation limit, and a pressure above the hydrate formation pressure. The rate of hydrate formation is increased by turbulence that keeps the water, gas, and the stream elements intermixed. By modifying the inner wall to be hydrophobic, the wall will prefer hydrocarbons to water. Thus, hydrocarbons flowing through the conduit will wet the inner wall, and prevent hydrate deposits, thereby making the inner wall hydrate-phobic. This is advantageous over traditional systems that merely inject chemical inhibitors into a stream flowing through the conduit because chemicals do not need to be continually added.
The term “hydrophobic,” as used herein, refers to a tendency to not dissolve (i.e., associate) readily in water. A moiety may be hydrophobic by preferring to bond or associate with other hydrophobic moieties or molecules, thereby excluding water molecules. The term “hydrate-phobic” refers to a tendency to not be wetted or covered by hydrates.
One skilled in the art will recognize that it may be advantageous to prepare the surface of the inner wall of a conduit prior to modifying (e.g., coating) the wall. In particular, surface preparations of steel conduits are desirable to assure OH— groups are available for bonding. The primary bonding mechanism of steel with various surface modifications or coatings is through OH— groups found in steel compositions. Thus, surface preparations typically involve removing any oxide layers and/or other impurities (i.e., scale) found on the surface of a steel conduit to expose or create OH— groups for bonding. Surface preparations may include a thermal cleaning step, a chemical cleaning or etching step, a mechanical cleaning step, a blasting step, or a combination thereof. For example, a surface preparation process may include a thermal and chemical cleaning step involving etching the surface with a conventional halogenated solvent at 700° F. for 2-4 hours and then blasting the surface with alumina and titania particles of a specific size to create a desired anchor pattern on the surface. In other cases, mechanically clean surfaces—e.g., surfaces that have been electro-polished—may only require a rinse with ethyl alcohol to prepare the surface for coating.
In some embodiments of the present disclosure, a priming step may be desirable after the surface preparation step and before the modifying or coating step. Such a priming step may include spraying the conduit with (or flowing through the conduit) priming molecules (e.g., siloxane) used to bond with the exposed OH— groups (from the surface preparation step) and a subsequently applied coating.
In one embodiment, the inner wall of a conduit is modified to be hydrophobic or hydrate-phobic by attaching self-assembling molecules to the inner wall of a conduit to form a self-assembled monolayer (SAM). For example, 14-phenyl-1-tetradecanethiol can be synthesized from (commercially available) 14-phenyl-11-tetradecen-1-ol. C 8 -thiol to C 18 -thiol or other SAMs, with chemistries similar to hydrate anti-agglomerate molecules, can be selectively adsorbed at the inner wall interface to construct an organized and oriented monolayer. Some SAMs may be applied at temperatures of less than 200° F. and atmospheric pressure.
Anti-agglomerates generally act to prevent smaller hydrates from agglomerating into larger hydrate crystals so that the smaller hydrates can be pumped through the conduit. Examples of anti-agglomerate molecules that may be coated to the inner wall of a conduit include tributylhexadecylphosphonium bromide, tributylhexadecyl-ammonium bromide, and other alkylated ammonium, phosphonium or sulphonium compounds, zwitterionic compounds such as R(CH 3 ) 2 N + —(CH 2 ) 4 —SO 3 31 .
FIG. 1 :
Referring to FIG. 1 , molecules with hydrophobic tails 10 are attached to a substrate 12 to form a SAM. In a preferred embodiment, the substrate 12 is the inner wall of a conduit (e.g., pipeline). Each molecule 10 has a head end 14 and a tail end 16 . The head end 14 includes a functional group selected to bind to the substrate material 12 . Substrate material may include chromium steel, low alloy steel, titanium steel, stainless steel, any other steel alloy that may be found in conventional commercially available steel pipelines, corrosion resistant alloys (CRA), CRA with over-layers of gold, or other metals used to form a conduit. Suitable functional groups for use on the head end 14 include, for example, that of 14-phenyl-1-tetradecanethiol. The tail end 16 includes a chain 17 and optionally includes a functional group 18 selected to provide a hydrophobic SAM on the substrate 12 . Suitable functional groups 18 for use on the tail end 16 include hydrocarbons such as alkanes, alkenes, alkynes, cycloalkanes, cycloalkenes, cycloalkynes, and aromatic hydrocarbons, such as aryls. Further, C 8 through C 18 -thiols, amines, and phosphates are hydrophobic SAMs that may be used on the substrate material to make a conduit hydrophobic.
In another embodiment, the inner wall of a conduit is modified to be hydrophobic or hydrate-phobic by applying a plasma generated coating to the inner wall. Examples of plasma coating materials and methods may be found in U.S. Pat. No. 7,351,480 and U.S. Pat. No. 7,052,736, which are herein incorporated by reference in their entirety.
In certain embodiments, it may be desirable to recondition the inner wall of a conduit. For example, hydrophobic and hydrate-phobic qualities of the wall may be degraded during hydrate remediation or with time. Thus, by conditioning and/or chemical soaking, the inner wall may regain the desired hydrophobic and hydrate-phobic qualities that were lost.
Embodiments of the present disclosure have an advantage over traditional systems that inject chemicals into a stream flowing through a conduit or flowline (i.e., chemical-injecting systems). In chemical-injecting systems, chemicals used to prevent hydrate blockages are swept away by a stream flowing through the conduit, and thus, the chemicals must be continuously added. Advantageously, embodiments of the present disclosure do not require continuous addition of chemicals to prevent hydrate blockages.
While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. | A pipe system comprising a pipe comprising an exterior of the system, the pipe comprising an inner pipe wall; a hydrophobic layer interior to the inner pipe wall; and a liquid interior to the hydrophobic layer and interior to the inner pipe wall, the liquid comprising water and one or more hydrocarbons. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fusion protein, more particularly, to a fusion protein for inhibiting cervical cancer induced or caused by HPV type 16 and pharmaceutical compositions thereof.
2. Description of Related Art
Currently, the incidence ratio of cervical cancer has remained high among all woman cancer patients. There are no any obvious symptoms of general variation of cervical epithelium or early cervical cancer. Although cervical cancer can be successfully treated in its early stages, prevention is still much better than treatment. Therefore, the researchers in this field have been making effort to find out the most efficient way to prevent cervical cancer.
It is already proved that human papillomavirus, HPV is highly related with cervical cancer. Some types (e.g. type 16, or 18) of DNA sequence of HPV had been found in cervical cancer cells, about 75%˜100%, but it is still not clear what the mechanism is in causing the cancer. Lately, research has found that the early gene product of virus—protein E6 and E7 of highly dangerous type 16, 18 and 31 of HPV easily combines with the product of genes Rb and p53 and thus reduce the ability of anti-tumor agent. This explains that HPV is not functioning alone when causing cancer but is assisted by environmental factors. Moreover, E7 protein expresses continuously in cervical cancer cells and carcinoma tissues. E7 protein also plays an important role in the process of maintaining shifted malignant tissue phenotype.
The cancer immune therapy is mainly displayed with cell-mediated immunization, assisted by humoral immunization. Cells involved in cell-mediated immunization are cytotoxic T lymphocytes (CTL), NK and macrophages. CTL is triggered by interlukin-2, and then identified by T cells. The major histocompatibility complex (MHC) on the cancer cells with antigen present appears and releases lysozyme to destroy the cancer cells and restrain the proliferation of cancer cells. CTL protection is proved to inhibit cancers caused by HPV. Therefore if it is possible to induce the proliferation of the HPV-antigen-specific CTL, for example, CD 8 + T lymphocytes, by enhancing complexes of HPV antigen and MHC class I presenting on cancer cells, the strategy of CTL induction with E7 antigen can be able to control carcinoma cell directly and beneficial for immunological prevention and treatment.
It is proved by research that cervical cancer is able to be prevented by vaccine injection. E7 proteins of HPV are highly common in carcinoma tissues or the tissues before carcinoma damage, therefore, E7 protein has the potential for developing as a vaccine. Basically, HPV type 16 and HPV type 18 are serious causes of not only cervical cancer, they are also dangerous factors for inducing lung cancer in females. The carcinogenic proteins E6 and E7 can be transferred to lungs through the circulation of blood and they decompose the anti-tumor proteins produced by gene Rb and p53. Once the anti-tumor genes or the proteins produced by them are deactivated, cancer cells show up. Though the present DNA vaccine does have a long term effect, on the other hand, it has high production costs. The main factor of restrained development in the DNA vaccine is the highly dangerous nature of the virus itself, which mutates easily. Furthermore, when applying E7 protein in gene therapy to cervical cancer, the induced immune response is usually induced weakly because of the weak antigen character of E7 protein of HPV virus. The effect of the prophylaxis and the therapy of cervical cancer are not able to be evaluated because of frail immune response.
Generally, the specific antigen of cancer cells needs to be modified and combined with MHC-I then presented to the cell surface in order to trigger the CD8 + cells and elicit cell-mediated system. The research shows that the HPV type 16 E7 gene can be found in cervical cancer tissues but there is a lack of the specific MHC-I complex to present to the cell surface for showing E7 antigen. Therefore, HPV type 16 E7 protein will not be present to or initiate the cellular immune system of the host cell and then HPV escapes from the detection or monitoring of host. Usually, when E7 protein is injected in vivo, it is considered as external antigens. The E7 vaccination can only be induced the humor immune response thus lowering the effect to elicit cell-mediated immunity. Hence, it is necessary to develop a transportation system of sending the intact foreign protein into cytoplasm and induce effective immune response.
Therefore, it is desirable to provide an fusion protein for inhibiting cervical cancer to mitigate and/or obviate the aforementioned problems.
SUMMARY OF THE INVENTION
A fusion protein for inducing immune response of specific cancers is disclosed, especially to some weak antigen viruses, which do not easily induce immune response. The fusion protein of the present invention can effectively inhibit the proliferation of carcinoma cells and lower the carcinoma level, and moreover can to prevent cancers.
The fusion protein of the present invention is able to induce CTL and antibody protection in vivo, then further is able to destroy the infected cells by presenting the antigen. A pharmaceutical composition for preventing or inhibiting cancer cells induced by human papillomavirus type 16 is also disclosed in the present invention. The pharmaceutical composition of the present invention also comprises a medical compound such as a fusion protein for preventing or inhibiting cancer induced by human papillomavirus type 16, wherein the compound is able to control the proliferation or the increase of carcinoma cells.
The fusion protein, T cell vaccine, or the pharmaceutical composition includes the fusion protein for inhibiting or preventing cancer induced by human papillomavirus type 16 of the present invention comprise: an E7 peptide segment of human papillomavirus type 16; a translocating peptide segment possessing translocation function; and a peptide fragment having a carboxyl terminal section.
The cancer induced by human papillomavirus type 16 can be inhibited or prevented by the fusion protein of the present invention or the pharmaceutical composition thereof. More precisely, the cancer is cervical cancer or lung cancer. In the fusion protein of the present invention, the nucleotide sequence of E7 peptide segment of human papillomavirus type 16 is preferred as SEQ. ID. NO. 1. The peptide fragment can be selected from any known peptide fragment in the art, which has translocation function, and preferably is a part of pseudomonas exotoxin A. The peptide fragment of carboxyl terminal section can be selected from any known sequence of carboxyl terminal section in the art. Preferably, the peptide fragment of carboxyl terminal section is part of pseudomonas exotoxin, and, the peptide fragment of carboxyl terminal section comprises an amino acid sequence of KDEL, the peptide sequence is SEQ.ID.NO. 2.
The preferable amino acid sequence of fusion protein of the present invention is SEQ.ID.NO. 3.
The present invention also discloses an antibody composition, which is combined E7 peptide, wherein the nucleotide sequence corresponding to the E7 peptide is SEQ. ID. NO. 1. The antibody composition of the present invention is able to detect the antigen of E7 peptide in vivo and then binds together in a way of “key and lock”.
The fusion protein of the present invention can be applied for inhibiting or preventing the infection of human papillomavirus type 16. The pharmaceutical composition of the present invention can further include an adjuvant for enhancing the medical effect. The adjuvant can be any conventional adjuvant of the art. Preferably, the adjuvant is aluminum gel, oily adjuvant such as Freund's FCA, or FIA, mannide mono-oleate emulsifier, ISA 206, or ISA 720. More preferably, the adjuvant is ISA 206.
The present invention is applied with the property of bacterial exotoxin in order to combine the bacterial exotoxin carried with protein and the surface acceptor of cell membrane of target cell (antigen presenting cell), the protein thus entering the cell and translocating the protein to cytoplasm by its natural ability of bacterial exotoxin; in the mean time, the external protein in cytoplasm can be prepared into small peptide and combined to MHC I or MHC II, and presented at the outside surface of the antigen presenting cell. The cell combined with MHC II or I will be identified by CD4 + cells or CD8 + cells, further induce a series of immune responses, and the immune ability of the fusion protein of the present invention is thus performed.
The pharmaceutical composition of the present invention can selectively comprise any conventional adjuvant, dispersant, humectant (for example: Tween 80) and suspension to produce sterile injection, for example, a sterile injectable composition can be a solution or suspension in a non-toxic parenterally acceptable diluent or solvent, such as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that can be employed, mannitol or water is preferred. In addition, fixed oils are conventionally employed as a solvent or suspending medium (e.g., synthetic mono- or diglycerides). Fatty acid, (e.g. oleic acid or glyceride derivatives thereof), and pharmaceutically acceptable natural oils (e.g. olive oil or castor oil, especially polyoxyethylated derivatives thereof) can be used in the preparation of injected composition. These oil solutions or suspensions can also contain a long chain alcohol diluent or dispersant, carboxymethyl cellulose, or similar dispersing agents. Other commonly used surfactants such as Tweens, Spans, other similar emulsifying agents, or bioavailability enhancers which are commonly used in the manufacture of pharmaceutically acceptable solid, liquid, or other dosage forms can also be used for the purpose of formulation.
A composition for oral administration can be any orally acceptable dosage form including capsules, tablets, emulsions and aqueous suspensions, dispersions, and solutions. In the case of tablets, the preferable vector is lactose, or corn starch. Lubricating agents, such as magnesium stearate, are also typically added. For oral administration in a capsule form, the used diluent is preferred to be lactose, or dried corn starch. When aqueous suspensions or emulsions are administered orally, the active ingredient can be suspended or dissolved in an oily phase combined with emulsifying or suspending agents. If necessary, certain sweetening, flavoring, or coloring agents can be added. vector.
The vector in the pharmaceutical composition must be “acceptable” in the sense that it is compatible with the active ingredient of the composition (and preferably, capable of stabilizing the active ingredient) and not deleterious to the subject to be treated. Examples of other vectors include colloidal silicon oxide, magnesium stearate, cellulose, sodium lauryl sulfate, and D&C Yellow # 10.
The fusion protein of the present invention or the pharmaceutical composition thereof can inhibit or prevent the disease induced by the infection of human papillomavirus type 16. Moreover, the concentration of the antibody induced by the fusion protein of the present invention or the pharmaceutical composition in a subject can last for a long time, and further enhance the medical effect.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the flow chart for a 8.0-kb plasmid (named pET-E7-KDEL3) encoding PE(ΔIII)-E7-KDELKDELKDEL (named PE(ΔIII)-E7-KDEL3) construction in example 2;
FIG. 2 shows the result of in vivo tumor protection experiments in example 2; 100% of mice receiving PE(ΔIII)-E7-KDEL3 protein remained tumor-free 60 days after TC-1 challenge. In contrast, all of the unvaccinated mice and mice receiving E7, PE(ΔIII), and PE(ΔIII)-E7 protein groups developed tumors within 15 days after tumor challenge;
FIG. 3 shows the numbers of E7-specific IFN-γ-secreting CD8 + T cell precursors in PE(ΔIII)-E7-KDEL3 group in example 6;
FIG. 4 shows the results for evaluation of the PE(ΔIII)-E7-KDEL3 protein enhancing the titer of anti-E7 antibody in example 7;
FIG. 5 shows the numbers of E7-specific CD 8 + T lymphocytes secreting from mice vaccinated with fusion proteins of the present invention with or without an adjuvant in example 8;
FIG. 6 shows the anti-tumor effects in mice with or without an adjuvant in example 8;
FIG. 7A shows the pulmonary tumor nodules in the in vivo tumor treatment experiments in example 9, wherein the symbols illustrate: (i) control group, (ii) E7, (iii) PE(ΔIII), (ix) PE(ΔIII)-E7, and (x) PE(ΔIII)-E7-KDEL3);
FIG. 7B shows the anti tumor effects of mice vaccinated with various times of PE(ΔIII)-E7-KDEL3 protein in example 9;
FIG. 8A shows the tumor prevention effects of mice vaccinated with various times of fusion protein in vivo in example 10; and
FIG. 8B shows the tumor suppression effects of mice treated with various times of fusion protein in vivo in example 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
EXAMPLE 1
Synthesis of E7 Nucleotide and KDEL Sequence
HPV type 16 E7 protein sequence (NC — 001526, SEQ.ID.NO. 3) was found in the database of National Center for Biotechnology Information (NCBI), U.S.A., 98 amino acid were collected in total.
The method disclosed in Taiwan patent application number 92126644 was conducted to express HPV16 E7 protein by E. coli system in large scale. Modification of the nucleotides in the present embodiment is to replace single base of wild type virus sequence with another base that expressed well in E. coli system, allowing target proteins expressed in E. coli the same as that expressed naturally. The modified sequence of HPV16 E7 nucleotide is SEQ.ID.NO. 1.
Eight pairs of primers were used for the synthesis of polynucleotides in the present example. The polynucleotide are synthesized by polymerase chain reaction (PCR). The sequence of all primers are shown in table 1. The sequences underlined represent as complementary fragments to a specific sequences.
At first, F1 and R1 primers are used to perform polyneucleotides synthesis by PCR without DNA template. There are 15 bases designed for complementary to each other at 3′ end of the both primers, and a double strand DNA template was obtained thereby. After the first PCR, 1 μl of amplicon was used as DNA template to conduct the second PCR, and 4 μl of primers of F1, R2, required dNTPs, reagent and Pfu polymerase were mixed to perform the second PCR. The modified nucleotide sequence SEQ.ID.NO. 1 was synthesized after eight times of PCR as described above.
Signal peptides with KDEL sequence are prepared in the same method illustrated above. The primer sequence is shown as K3F AND K3R in table 1. The peptide sequence of the synthesized KDEL is SEQ.ID.NO. 2.
TABLE 1
Pri-
Seq.
Seq.
mers
ID.
Sequence listing
E7
F1
4
5′-AGAATTC ATG CAC GGT GAC ACC
CCG ACC CTG CAC GAA TAC ATG CTG
GAC CTC -3′
R1
5
5′- C GTA GCA GTA CAG GTC GGT GGT
TTC CGG CTG GAG GTC CAG CAT
GTA -3′
R2
6
5′- TTC GTC TTC TTC TTC GGA GGA GTC
GTT CAG CTG TT C GTA GCA GTA CAG
GTC -3′
R3
7
5′- GTC CGG TTC AGC CTG ACC AGC
CGG ACC GTC GAT TTC GTC TTC TTC
TTC -3′
R4
8
5′-T GCA GCA GAA GGT AAC GAT GTT
GTA GTG AGC AGC GTC CGG TTC AGC
CTG -3′
R5
9
5′-CTG AAC GCA CAG ACG CAG GGT
GGA GTC GCA TT T GCA GCA GAA GGT
AAC -3′
R6
10
5′- TTC CAG GGT ACG GAT GTC AAC
GTG GGT GGA CTG AAC GCA CAG
ACG -3′
R7
11
5′- AAC GAT ACC CAG GGT ACC CAT
CAG CAG GTC TTC CAG GGT ACG
GAT -3′
R8
12
5′- TTT GAA TTC CGG TTT CTG GGA
GCA GAT CGG GCA AAC GAT ACC CAG
GGT AC -3′
KDEL
K3F
13
5′- AGAATTCGTCGAC TAC CTC AAA
AAA GAC GAA CTG AGA GAT GAA
CTG -3′
K3R
14
5′-GTG GTG GTG CTC GAG TCA TTA
CAG TTC GTC TTT CAG TTC ATC TCT
CAG TT -3′
EXAMPLE 2
Vector Construction of Plasmids
The E7 product obtained from PCR in example 1 is separated by 5% polyacrylamide agarose gel. The target product is purified according to the molecular weight of the product. VectorVectors pET or Ppe (ΔIII) are provided (J. R. Chen, C. W. Liao, S, J. T. Mao, and C. N. Weng, Vet. Microbiol. 80 (2001) 347-357) and digested with restriction endonuclease as well as vector the purified E7. Another electrophoresis is conducted with 5% polyacrylamide agarose gel for further isolating and purifying. Then 0.3 kb of E7 sequence fragment is obtained. 7.84 kb plasmid PE (ΔIII) is further constructed by ligasing the E7 fragment and the vectorvector, which comprises exotoxin A (ETA) but without enzyme toxic section. Moreover, a plasmid pPE (ΔIII)-E7 containing the fusion protein PE(ΔIII)-E7, and a 3.83 kb plasmid pE7 containing E7 fragment and pET23a are also constructed.
A 3.78 kb pKDEL3 plasmid which encodes n′-KDELRDELKDEL polypeptide fragment is obtained by digesting, purifying the amplicon (obtained from PCR with K3-F, and K3-R primers), and further inserting into the site of Sall-Xhol of vector pET23a.
A 8.0 kb plasmid pPE(DIII)-E7-K3 encoding fusion protein PE (ΔIII)-E7-K3 is obtained by digesting 1.47 kb KDEL sequence from pKDEL3 plasmid by restriction endonuclease Sall and Pstl, and further inserting into the spliced 6.5 kb, PE (ΔIII)-E7 plasmid DNA which is spliced by splicing by Xholl and Pstl. The flow chart of preparing plasmid mentioned above is as shown in FIG. 1 .
The plasmid constructed above is further transformed to E. coli and maintained in the bacteria strain JM108.
EXAMPLE 3
VectorVectorVector Purification of Protein
The plasmid synthesized above is further transformed into E. coli BL21 (DE3) pLys strain. The transformed E. coli BL21 (DE3) pLys strain is cultured in the 200 ml LB culture medium containing 200 μg/ml ampicillin until the culture concentration reach 0.3 under OD550 spectrum. Then after 1 mM IPTG (isopropylthio-β-D-galactoside, Promege, USA) is added, the E. coli BL21 (DE3) pLys strain is cultured for 2 hours. The grown cells are collected by centrifugation. A freeze-thraw method is conducted to the target protein contained cells to loose the structure of cell membrane. 10 ml lysis buffer (0.3 mg/ml lysozyme, 1 mM PMSF and 0.06 mg/ml DNAse I) is added to the cultured cells, and then placed at room temperature for 20 minutes. 1 ml 10% Triton X-100 is added, and placed at room temperature for 10 minutes. The target proteins are released and collected by centrifugation at a rate of 1200×g for 10 minutes, resulting pallet was washed with 1M or 2M urea. At the end, the collected protein of inclusion body is dissolved in 8 ml 8M urea.
The fusion proteins were then purified under the His-Tag system in the denatured condition as the manufacturer's manual (Novagen, USA). The denatured samples in 8M urea were loaded into a column packed with a NTA-Ni2 + -bind agarose resin. The bound proteins were then eluted with different pH buffer (from 8.0, 7.0, 6.5, 6.0, 5, 4, and 3.5) containing 6M urea, 0.3M NaCl, and 20 mM Tris-HCL and 20 mM phosphate buffer. After purified, protein elution fractions were analyzed for the purity and quantification by SDS-PAGE analysis as described previously. The purified protein product contained the amino acid sequence as shown in SQE:ID.NO. 3.
EXAMPLE 4
Preparing Carcinoma Cell Strain (TC-1)
HPV16 E6, E7 and ras oncogene were used to transform primary lung epithelial cells of C57BL/6 mice. This tumorigenic cell line was named TC-1. TC-1 cells were grown in RPMI 1640, supplemented with 10% (vol/vol) fetal bovine serum, 50 units/ml penicillin/streptomycin, 2 mM L-glutamine, 1 mM sodium pyruvate, 2 mM nonessential amino acids and 0.4 mg/ml G418 at 37° C. with 5% CO 2 . On the day of tumor challenge, tumor cells were harvested by trypsinization, washed twice with 1× Hanks buffered salt solution (HBSS) and finally resuspended in 1×HBSS to the designated concentration for injection.
EXAMPLE 5
In Vivo Tumor Protection Experiments
The testing protein samples: E7, PE (ΔIII), PE (ΔIII)-E7, PE (ΔIII)-E7-KDEL3 are diluted with a phosphate buffer solution in a ratio of 1:10 to make the concentration at 0.1 mg/ml. Then the test samples are incubated at 37° C. for 2 hours. The incubated samples are mixed with 10% ISA206 (Sepec, France) by a vortex to form 4 kinds of different vaccines. Then 0.1 mg of each vaccine obtained is injected to the mice for vaccination. These mice were then boosted subcutaneously two weeks later with the same regimen as the first vaccination. One week after last vaccination, mice were challenged with 5×10 4 TC-1 tumor cells by subcutaneous injection in the right leg. Naive mice received the same amount of TC-1 cells to assess natural tumor growth control. Tumor growth was monitored by visual inspection and palpation twice weekly until 7, 14, 20, 30, and 60 days after after tumor challenge. The spleens of the sacrificed mice are also taken out for further checking.
As shown in FIG. 2 , no cancer cells are found in the mice injected with PE (ΔIII)-E7-KDEL3. In other words, the percentage of the PE (ΔIII)-E7-KDEL3-injected mice without cancer cells is 100%. Moreover, even 60 days later, none of the PE (ΔIII)-E7-KDEL3-injected mice has cancer. In contrary, cancer cells can be found in the mice injected with E7, PE (ΔIII), or PE (ΔIII)-E7, or the mice of control. The longest period without cancer cells among these mice is 20 days. According to the result of the experiment, only fusion protein include the sequence of PE (ΔIII), and KDEL3, and the fragment of E7 can prevent and inhibit the growth of cancer cells in the cancer-inducing model illustrated above.
EXAMPLE 6
Cell Immune Experiment
Mice are injected, and cancer-induced as described in example 5. One week later, the mice are sacrificed and the spleen macrophages are taken out. Before intracellular cytokine staining, 3.5×10 5 pooled splenocytes from each vaccinated group were incubated for 16 hours with either 1 μg/ml of E7 peptide (aa 49-57) containing an MHC class I epitope for detecting E7-specific CD8 + T cell precursors. Cell surface marker staining of CD8 + or CD4 + and intracellular cytokine staining for IFN-γ, as well as FACScan analysis, were performed using conditions described by Cheng, et al. (Hum Gene Ther, 13:553-568, 2002) to compare the E7-sepcific immunological assays in mice received different regimens of vaccination.
In the present example, it is confirmed that PE (ΔIII)-E7-KDEL3 has influence for E7 specific immunization, as shown in FIG. 3 . In the mice of the group injected with PE (ΔIII)-E7-KDEL3, it is founded that the numbers of E7-specific IFN-γ-secreting CD8 + T cell precursors in PE(ΔIII)-E7-KDEL3 group were higher than those in the other groups (10.0±1.4 in naïve group, 14.0±2.1 in E7 group, 12.0±2.1 in PE(ΔIII) group, 36.0±2.8 in PE(ΔIII)-E7 group, 564.0±28.0 in PE(ΔIII)-E7-KDEL3, p<0.01, AVONA).
According to the result above, the number of E7-specific IFN-γ(+) CD8(+) T cell precursors of the mice vaccinated with PE(ΔIII)-E7-KDEL3 protein is 40 times higher than that vaccinated with E7.
EXAMPLE 7
E7 Specific Antibody Evaluation
Mice are vaccinated with 0.1 mg of the E7, PE (ΔIII), PE (ΔIII)-E7, PE (ΔIII)-E7-KDEL3 fusion proteins as described in example 5. Further boosts after one and two weeks later with the same regimen as the first vaccination are conducted. The mouse serum is collected at the 7 th day after the last immunization.
Briefly, a 96-microwell plate was coated with 100 μl of bacteria-derived HPV-16 E7 proteins (0.5 μg/ml) and incubated at 4° C. overnight. The wells were then blocked with phosphate-buffered saline (PBS) containing 20% feta bovine serum. Sera were prepared from mice of various vaccinated groupd serially diluted in PBS, added to the ELISA wells, and incubated at 37° C. for 2 hr. After washing with PBS containing 0.05% Tween 20, the plate was incubated with a 1:2000 dilution of a peroxidase-conjugated rabbit anti-mouse IgG antibody (Zymed, San Francisco, Calif.) at room temperature for 1 hr. The plate was washed, developed with 1-Step Turbo TMB-ELISA (Pierce, Rockford, Ill.), and stopped with 1 M H 2 SO4. The ELISA plate was read with a standard ELISA reader at 450 nm.
C57BL/6 mice were immunized subcutaneously with PE(ΔIII)-E7-KDEL3 mixed 10% ISA206 adjuvant one to three times. Sera were prepared and the E7-specific antibody titers were detected by the ELISA as described earlier.
In the present example, it is further confirmed that PE (ΔIII)-E7-KDEL3 is able to improve the potency of resisting E7 antibody. As shown in FIG. 4 , mice vaccinated with the PE(ΔIII)-KDEL/E7 protein generate highest titers of anti-E7 Ab's in the sera of mice compared with those vaccinated with other fusion protein (for 1:100 dilution, 0.629±0.093 in naïve group, 0.882±0.086 in E7 group, 0.690±0.06 in PE(ΔIII) group, 0.930±2.80.06 in PE(ΔIII)-E7 group, 3.593±0.54 in PE(ΔIII)-E7-KDEL3, p<0.01, AVONA). Apparently, PE(ΔIII)-E7-KDEL3 protein could also enhance the titer of anti-E7 antibody.
The data showed that PE(ΔIII)-E7-KDEL3 fusion protein could enhance E7-specific immunological responses (including the numbers of E7-specific CD4 + and CD8 + T lymphocytes and the titers of E7-specific antibodies).
All the obtained readings are expressed with Mean Value and Mean±SEM. The compared data from the experiment will be processed ANOVA analysis by Statistical Package for Social Sciences, SPSS 9.0, SPSS Inc, Chicago, Ill.; there is a significant difference of the data if the statistical error is under 0.05.
EXAMPLE 8
Application of an Adjuvant in a Vaccine Composition
In many cases, peptides or proteins are poorly immunogenic and hardly induce a response when they injected alone. Hence, an adjuvant is usually injected together with peptides or proteins. Examples of such adjuvants include BCG, incomplete Freund's adjuvant, cwellra toxin B, GM-CSF, ISA206 and IL-12, wherein ISA206 is used for the protein adjuvant of the present embodiment.
The fusion proteins here are PE (ΔIII)-E7, and PE (ΔIII)-E7-KDEL3. The process of mice vaccination was the same as that described above in examples 5 and 6. Samples of fusion proteins were mixed with or without 10% ISA206 adjuvant (SEPPIC, France). The result is shown in FIG. 5 , wherein the first sample group (i.e. the blank sample group) showed no significant immune response for E7 specific CD 8 + T lymphocytes stimulation. The same result can be found in the second sample group. In other words, no matter E7 is included in the vaccine or not, there is no significant numbers of antibody induced by the vaccine composition without adjuvants. However, the numbers of E7 specific CD 8 + T lymphocytes is about 600, which is 500-600 times higher than that induced by the vaccine composition without adjuvant.
As shown in FIG. 6 , the period for preventing the proliferation of cancer in the induced mice by administrating (through injection) the mice with the vaccine composition having PE (ΔIII)-E7-KDEL3 and adjuvant is 60 days. In contrary, for the mice administrated with the vaccine composition of PE (ΔIII)-E7-KDEL3 without an adjuvant, the population of the mice with tumor is almost the same as that of the control group which is not vaccinated with fusion proteins of the present invention. Mice immunized with PE(ΔIII)-E7-KDEL3 protein alone (i.e. without an adjuvant) could not generate potent E7-specific immunological responses and anti-tumor effects (data not shown). However, according to the result, vaccine compositions of PE(ΔIII)-E7-KDEL3 protein of the present invention comprising an adjuvant is preferred for application for capability to induce optimal immunological responses.
EXAMPLE 9
In vivo tumor treatment experiments were performed using a lung hematogenous spread model. C57BL/6 mice mice (five per group) were challenged with 5×10 4 cells/mouse TC-1 tumor cells via tail vein. Two days after tumor challenge, mice received 0.1 mg/mouse of E7, PE(ΔIII), PE(ΔIII)-E7 or PE(ΔIII)-E7-KDEL3 protein vaccines subcutaneously, followed by a booster with the same regimen every 7 days for 2 weeks (a total of four times, 0.3 mg protein). Mice receiving no vaccination were used as a negative control. Mice were sacrificed and lungs were explanted on day 30. The pulmonary tumor nodules in each mouse were evaluated and counted by experimenters blinded to sample identity.
The representative figures of pulmonary tumor nodules in various protein-vaccinated groups are shown in FIGS. 7A and 7B . As shown in FIG. 7A , only the mice accepting the PE(ΔIII)-E7-KDEL3 fusion protein don't have lung cancer. The mean lung weight (214.4±11.6) of the mice treated with PE(ΔIII)-E7-KDEL3 showed significantly lower than those of mice treated with PE(ΔIII)-E7 (673.6±20.8) or wild-type E7 protein (811.1±45.6) (one-way ANOVA, p<0.001) These data indicated that mice treated with PE(ΔIII)-E7-KDEL3 could control established E7-expressing tumors in the lungs.
EXAMPLE 10
Evaluation of the E7-specific immunological profiles of the mice immunized with different times of PE(ΔIII)-E7-KDEL3 protein vaccine could reflect the anti tumor effects of the mice. As described earlier in examples 5 and 6, mice were challenged with TC-1 tumor cells and then received 0.1 mg PE(ΔIII)-E7-KDEL3 protein from one to three times as described earlier. Mice were sacrificed on day 30 and the pulmonary tumor nodules in each mouse were evaluated and counted as described earlier.
As shown in FIG. 8A , all of the naïve mice and mice immunized one time of PE(ΔIII)-KDEL3 protein vaccine grew tumors within 14 days after tumor cell TC-1 challenged. And 60% or 100% of mice immunized with 2 or 3 times of PE(ΔIII)-KDEL3 protein vaccine were tumor-free 60 days after tumor challenge, respectively.
Similar phenomena were also observed in the tumor treatment experiments as described in example 9. The pulmonary tumor nodules decreased significantly from one to three shots of PE(ΔIII)-KDEL3 protein vaccine (103.0±3.8 for one time, 28.8±6.1 for two times, 0.6±0.4 for three times, p<0.001, ANOVA)
Our results show that increasing shots of PE(ΔIII)-KDEL3 protein vaccine could improve the preventive and therapeutic anti-tumor effects of E7-expressing tumor cells.
PE(ΔIII)-E7-KDEL protein could enhance MHC class I presentation of E7 in cells expressing this fusion protein to enhance E7-specific CD8+ T-cell activity in vivo.
According to the examples illustrated above, the fusion protein of the present invention can enhance the stimulation of the precursor of E7 specific CD 8 + T lymphocytes and CD 4 + T lymphocytes by enhancing the presentation of the E7 antigen through MHC I and II. The concentration of the E7 specific antibody can be increased through the mechanism illustrated above. Moreover, the cancer induced by E7 can be inhibited or prevented through the administration of the fusion protein of the present invention. In addition, the mice vaccinated by the fusion protein of the present invention have longer time for inhibiting cancer.
Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. | A fusion protein for inhibiting cervical cancer is disclosed, which comprises a peptide sequence of human papillomavirus type 16, a peptide translocating peptide for translocation, and a peptide within a carboxyl terminal fragment. The present invention further comprising a composition of antibody, which conjugates to E7 peptide, wherein the nucleotide sequence corresponding to the amino acid sequence of the E7 peptide is shown as SEQ. ID. NO.1. | 2 |
This is a continuation of application Ser. No. 07/730,321, filed Jul. 15, 1991, which in turn is a continuation of application Ser. No. 07/619,150, filed Nov. 27, 1990, which in turn is a continuation of application Ser. No. 07/527,392, filed May 23, 1990, which in turn is a continuation of application Ser. No. 07/420,204, filed Oct. 12, 1989, which in turn is a continuation of application Ser. No. 07/322,277, filed Mar. 10, 1989, which in turn is a continuation of application Ser. No. 07/091,238, filed Aug. 31, 1987, which in turn is a continuation-in-part of application Ser. No. 06/909,256, filed Sept. 19, 1986, all of which are now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to concrete admixtures. In one particular aspect it relates to concrete admixtures for use as cold weather concrete set accelerators, and to methods for their use.
Low or freezing temperatures ( e.g., 40° to 15° F.) presents special problems in mixing, placing and curing of concrete. Concrete may freeze while saturated and subsequently be of low strength, or there may be a slow development of strength.
The American Concrete Institute (ACI) Report 306R-78 on Cold Weather Concreting, sets forth standard practices to prevent freezing, and assure the safe development of concrete strength during curing at ambient freezing conditions. Heating of materials, including mix water and aggregates, are mandatory. Protective insulating coverings, heating enclosures and proper curing conditions are described.
An additional factor (not often reported) associated with freezing temperatures, is the distress of the concrete worker operating under adverse conditions. Even if dressed warmly, the concrete worker wishes to finish a pour or complete the finishing as fast as possible, and move indoors out of the wind and cold. Thus, an accelerated set time is an important aspect of cold weather concreting.
While the prior art has addressed the problems of using concrete in cold weather (e.g., the use of calcium chloride as the principle accelerating admixture), it has not successfully developed admixtures which are, (1) non-corrosive, and (2) meet or exceed the rate-of-hardening and compressive strength performance at about 13° to 40° F., of a plain concrete mix at 50° F.
The present invention provides admixture compositions which meet these prior art limitations.
THE INVENTION
Broadly, the present invention provides a chloride-free admixture for use as a cold weather concrete set accelerator which comprises
(1) 100 parts by weight of at least one soluble inorganic salt having freezing point depressant properties,
(2) from 13.3 to 30 parts by weight of at least one water-reducing dispersant, e.g., superplasticizer,
(3) from 3 to 30 parts by weight of at least one inorganic early set and strength accelerator, and
(4) from 0 to 10 parts by weight of at least one organic set accelerator.
Preferably the quantity of component 2 should be greater than 15 parts by weight.
Preferably the quantity of component 3 is from 5 to 10 parts by weight.
Preferably component 4 is present in an amount of from 1.3 to 6 parts by weight.
The proportions given above are parts by dry weight of the total weight of components 1-4, neglecting any water which may be present. The admixture of the invention may be added as a solid direct to the concrete mix water. Preferably the admixture is in the form of an aqueous solution.
The set accelerating admixtures of this invention combine two beneficial effects:
(1) They depress the mix water freezing point, so that a concrete mix will not freeze during the first few critical hours of curing at temperatures below 32° F., and
(2) They reduce the quantity of mix water necessary for curing, which improves early concrete strength development. The reduction in mix water also has an effect on freezing point depression, because it allows for a more concentrated solution of the admixture.
DESCRIPTION OF PREFERRED EMBODIMENTS
Component 1 is preferably selected from ammonium, alkali and alkaline earth nitrates and nitrites, more preferably from calcium and sodium nitrate and nitrite. Calcium nitrate is particularly preferred. Up to 50% of the inorganic salt of component 1 may be replaced by urea.
Component 2 is preferably an alkali or alkaline earth salt of a napthalene sulphonate/formaldehyde condensate, more preferably a sodium or calcium salt or an acrylic copolymer, e.g., poly[hydroxy ethyl methacrylate/acrylic acid]. Particularly preferred is napthalene sulphonate/formaldehyde condensate in sodium salt form.
Component 3 is preferably selected from ammonium, alkali or alkaline earth thiocyanates and thiosulphates, more preferably from calcium, ammonium and sodium thiocyanates. Particularly preferred is sodium thiocyanate.
Component 4 is preferably selected from methylolgylclurils, dimethylolurea, mono- and di-(N-methylol) hydantoin, mono-and di(N-methylol) dimethylhydantoin, N-methylolacrylamide, tri-(N-methylol) melamine, N-hydroxyethylpiperidine, N,N-bis(2-hydroxyethyl)piperazine, glutaraldehyde, pyruvaldehyde, furfural and water soluble urea-formaldehyde resins. More preferably, component 4 is selected from methylolglycolurils, e.g., tri(N-methylol)glycoluril and tetra (N-methylol)blydoluril, particularly tetra (N-methylol)glycoluril.
A preferred admixture according to the invention consists of (1) calcium nitrate, (2) sodium salt of naphthalene sulphonate/formaldehyde condensate, (3) sodium thiocyanate and (4) tetra(N-methylol)glycoluril, in the proportions by weight: 100 parts (1), 20 parts (2), 6.7 parts (3) and 4 parts (4). This preferred admixture is preferably used in the form of an aqueous solution containing 40%-60% dry weight of components 1-4, particularly 50% wt.
The admixtures of the invention may be used over a wide range of temperatures from about 70° F. to about -5° F. The amount of admixture which is added to the concrete may be from 0.13 to 5.6 parts (dry weight) per 100 parts dry weight of cementitious material in the concrete (e.g., portland cement plus pozzolanic material such as fly ash). For the above preferred admixture, the dose range is from 1.3 to 4.6 parts/100 parts cement, and the lower the ambient temperature the higher will be the dosage required. Thus a dosage of 2.6 parts/100 parts cement of the preferred admixture will prevent a concrete mix from freezing at temperatures down to about -6° F., while for lower temperatures a dosage of 3.9 parts/100 parts cement is preferred.
While the admixture of the invention may be used with any of ASTM type I to V cements, types I and II are preferred. The admixtures may be used in cement motors as well as in concrete.
The invention also provides a method for accelerating the set of a concrete or cement mortar mix, suitable for use in cold weather conditions, comprising adding to the mix from 0.13 to 5.6 parts (dry weight) of an admixture according to the invention per 100 parts dry weight of cementitious material in the mix. The concrete or cement mortar so obtained will contain the following amounts of components 1-4, defined above:
______________________________________Component parts/100 parts cement______________________________________1 0.5-4.02 0.1-0.83 0.033-0.64 0.0-0.16 preferably 0.02-0.16Preferred amounts are:1 2.0-3.02 0.4-0.63 0.1-0.64 0.04-0.12______________________________________
A similar method which may be substituted for that already described, comprises adding to the concrete or cement mortar
(A) 0.5 to 4% by weight of cement of at least one component 1),
(B) 0.1 to 0.8% by weight of cement of at least one component 2),
(C) 0.033 to 0.6% by weight of cement of at least one component 3), and
(D) 0 to 0.16% of cement of a least one component 4).
In the preferred method, at least one component 4) is added in the amount of from 0.02 to 0.16% wt. of cement.
In the Example the following terms are used in the Tables.
______________________________________Formula Plain refers to a concrete mix without admixture. It is used as a reference. The letters A to CC refer to the admixture formulas set out in the chart below.Dose Amount of admixture added in fluid ounces per 100 lbs. of cement.Slump The drop in inches of a 12 inch cone. ASTM C 143Air The percent of entrained air.Water Red Refers to the amount in % of water reduced from the plain concrete mix. The amount listed for the plain mix is the initial starting amount in lbs./cu. yd.PSI/Percent PSI = pounds per square inch of compressive strength of a concrete sample. The percent is the percent of increase or decrease of breaking strength based on the plain mix at 100%.Micro-Air An admixture for entraining air in concrete. The admixture meets the requirements of ASTMC-260, AASHTO M-154 and CRD-C13. (Master Builders - Cleveland OH).MB-VR An admixture for entraining air in concrete. (Master Builders Neutralised VINSOL). The admixture meets the requirements of ASTM C-260, AASHTO M-154 and CRD-C13.ROH Rate of Hardening. The time in hours to reach initial set. For plain concrete it is the actual time in hours to reach initial set. The ROH for admixture concrete is the difference in set time between plain and admixture concrete. ROH of admixture minus ROH of plain equals relative ROH of admixture concrete. ASTM C 403-80.______________________________________
All concrete mixes were based on a cubic yard formula of about 4000 lbs.
(1) Cement (Type I) 517 lbs.
(2) Sand and Stone about 3200 lbs. Sand to Stone ratio of 40:60 to 50:50. The stone used was 1/4 in. topsize crushed limestone.
(3) Water as indicated in the Tables.
4) Admixture as indicated in the Tables.
The procedure for the experiments was as follows:
Concrete mixes with addition of admixtures of the invention are prepared according to the concrete formulation of the plain reference. Mixing together the concrete component and the admixtures is carried cut as follows:
Mix water in the amount of about 80 % of that of the plain reference is added to a conventional cement mixer and the admixture then added to the water. The cement, sand and stone are further added.
Then the remaining 20% of water is used in part to adjust the slump to the slump of the plain reference.
The concrete is then poured into 10 cm cubes which are covered to prevent moisture loss. The concrete cubes are stored for the time and at the temperature indicated in Examples I to VI.
__________________________________________________________________________ADMIXTURE FORMULATIONSFORMULA/POUNDS PER 100 LBS. OF CEMENT__________________________________________________________________________Materials A B C D E F G H I J K__________________________________________________________________________(1) Calcium nitrate 3.500 3.000 3.000 3.000 3.000 3.000 3.000 3.000 3.000 2.500 2.500(2) Sodium salt of 0.700 0.600 0.600 0.600 0.600 0.400 0.400 0.400 0.400 0.500 0.500naphthalene sulfo-nate-formaldehyderesin(3) Sodium thiocyanate 0.233 0.600 0.600 0.200 0.200 0.600 0.600 0.200 0.200 0.400 0.167(4) Tetra (N-methylol) 0.117 0.120 0.049 0.120 0.040 0.120 0.040 0.120 0.040 0.080 0.100glycoluriel(5) Water Added to give dose rate indicated in the Tables.__________________________________________________________________________Materials L M N O P Q R S T U V__________________________________________________________________________(1) Calcium nitrate 2.000 2.000 2.000 2.000 2.000 2.000 2.000 2.000 2.000 1.500 1.000(2) Sodium salt of 0.600 0.600 0.600 0.600 0.400 0.400 0.400 0.400 0.400 0.300 0.200naphthalene sulfo-nate-formaldehyderesin(3) Sodium thiocyanate 0.600 0.600 0.200 0.200 0.600 0.200 0.200 0.133 0.060 0.100 0.66(4) Tetra (N-methylol) 0.120 0.040 0.120 0.04 0.04 0.120 0.040 0.080 0.120 0.060 0.04glycoluriel(5) Water Added to give dose rate indicated in the Tables.__________________________________________________________________________Materials W X Y Z AA BB CC DD__________________________________________________________________________(1) Calcium nitrate 3.000 3.000 2.000 3.000 3.000 3.000 3.000(1) Calcium nitrate 3.000 1.000(2) Calcium Napthalene 0.600 0.600Sulfonate(2) Napthalene Sulfonate 0.600 0.600 0.600 0.600 0.600 0.600formaldehydeCondensate(3) Sodium Thiocyanate 0.200 0.200 0.200 0.200 0.200 0.200 0.200(4) Tetra (N-Methylol) 0.120 0.120 0.120 0.120Glycoluriel(4) Ammonium 0.200Thiocyanate(4) Pyruvic Aldehyde 0.1200(4) Glutaraldehyde 0.1200(4) N-Hydroxyethyl- 0.1200pyridine(4) N-N-Bis(2-Hydroxy- 0.1200ethyl) PiperazineSodium Acetate* 0.042 0.042 0.042 0.042 0.042 0.042 0.042 0.042Water Added to give dose rate indicated in the tables__________________________________________________________________________ *Sodium Acetate buffering agent to maintain concrete pH from Ph 4-7.
EXAMPLE
The results of Tables I to VI show that the admixture compositions of this invention are capable of protesting concrete systems against freezing down to 16° F. Table VI shows that the admixtures also give satisfactory results when used at temperatures up to 70° F.
TABLE I__________________________________________________________________________ PSI/PercentTrial Formula Dose Slump Air ROH Water Red. 1 Day 3 Day 7 Day 28 Day__________________________________________________________________________0 Plain -- 7.25 6.8 Frozen 286.0 lbs. 54 353 1050 2732 Micro-Air 0.65 100 100 100 1001 CaCl.sub.2 2.00 7.50 5.9 Frozen -4.9% 100 671 1775 4513 Micro-Air 0.59 185 190 169 1652 U 45.00 7.50 6.8 5.500* -4.9% 134 647 1762 4279 Micro-Air 0.77 248 183 168 1573 D 90.00 7.00 6.0 5.130* -5.2% 164 852 2718 4979 Micro-Air 0.74 304 241 259 182__________________________________________________________________________ All concrete samples (0 to 3) were made at 40° F., placed at 20° F., and cured at variable temperatures of from 6° to 66° F. *actual times
TABLE II__________________________________________________________________________ PSI/PercentTrial Formula Dose Slump Air ROH Water Red. 1 Day 3 Day 7 Day 28 Day__________________________________________________________________________0 Plain -- 5.00 1.9 7.82 296.0 lbs. 399 1675 2961 5259 100 100 100 1001 A 105.00 5.00 3.0 -4.57 10.1% 388 1234 3201 6347 97 74 108 1212 D 90.00 5.25 2.7 -4.20 9.8% 390 1091 3208 6369 98 65 108 1213 K 75.00 5.00 2.3 -4.20 7.1% 303 675 2815 5200 76 40 95 994 S 60.00 5.00 2.2 -4.32 9.5% 409 834 3190 5641 103 50 108 1075 U 45.00 5.00 1.8 -3.07 7.1% 393 800 2339 5284 98 48 96 100__________________________________________________________________________ Trial #0 Plain concrete made and cured at 50° F. Trials #1-5 concrete samples made at 50° F., cured at 16-20° F. for 3 days, then cured at 50° F.
TABLE III__________________________________________________________________________ PSI/PercentTrial Formula Dose Slump Air ROH Water Red. 1 Day 3 Day 7 Day 28 Day__________________________________________________________________________0 Plain -- 4.75 5.0 10.50 290.0 lbs. 284 1565 3071 5460 Micro-Air 0.81 100 100 100 1001 J 100.00 5.25 6.0 -5.87 -9.0% 297 1125 4384 6604 Micro-Air 0.81 105 72 143 12199 Alternate -- 5.00 5.8 5.00 -1.0% 140 487 1550 3675 Plain 0.81 49 31 50 67 Micro-Air__________________________________________________________________________ Trial #0, concrete samples made and cured at 50° F. Trials #1 and 99, concrete samples made at 50° F., placed at 28° F., and cured at 28° F. for 1-3 days. All 7 and 28 day samples cured at 50° F.
TABLE IV__________________________________________________________________________ PSI/PercentTrial Formula Dose.sup.(1) Slump Air ROH Water Red. 1 Day 28 Day__________________________________________________________________________0 Plain -- 4.88 1.6 8.75 298.0 lbs. 353 4959 100 1001 B 5.00 2.8 -4.87 9.4% 328 6311 93 1282 C 5.25 3.3 -4.75 8.7% 228 6462 65 1303 D 5.25 3.1 -4.62 12.1% 269 6425 76 1304 E 5.25 3.0 -4.75 6.7% 228 6659 65 1345 F 5.25 2.4 -5.00 5.0% 294 5900 83 1196 G 5.00 2.7 -5.00 9.4% 225 7125 64 1447 H 5.00 2.5 -4.87 8.7% 276 6578 78 1338 I 5.00 2.8 -5.37 6.4% 266 6217 75 1269 J 5.19 2.8 -4.87 9.1% 292 6378 83 12910 L 5.25 3.1 -4.37 14.1% 318 6812 90 13711 M 5.25 3.5 -4.87 11.7% 287 7112 81 14312 N 5.50 2.9 -4.25 11.7% 269 6184 76 12513 O 5.25 2.9 -4.37 13.4% 232 6234 66 12614 P 5.00 2.4 -4.62 6.7% 266 6219 75 12515 Q 5.00 2.5 -4.75 7.4% 256 6212 73 12516 R 5.25 2.7 -4.50 8.1% 209 6081 59 12317 T 5.25 2.9 -4.50 9.4% 209 5787 59 117__________________________________________________________________________ Trial #0, concrete samples made, poured and cured at 50° F. Trials #1 to 17 concrete samples made 50° F., placed and cured at 24° F. for one day, and then cured at 50° F. .sup.(1) Admixture diluted with water up to a convient amount.
TABLE V__________________________________________________________________________ PSI/PercentTrial Formula Dose Slump Air ROH Water Red. 1 Day 3 Day 7 Day 28 Day__________________________________________________________________________0 Plain -- 3.00 5.7 5.375 267.0 lbs. 1169 2887 4281 5550 MB-VR 1.00 100 100 100 1001 V 30.00 2.00 5.2 -2.125 6.7% 1909 4056 5697 7234 MB-VR 1.64 163 140 133 1302 S 60.00 2.25 6.0 -2.625 8.2% 2041 4268 5684 6919 MB-VR 1.59 175 160 133 1253 D 90.00 2.25 6.4 -2.875 10.5% 2506 5228 6078 7584 MB-VR 1.49 214 181 142 137__________________________________________________________________________ Trials #0 to 3 concrete samples were all made, placed and cured at 70° F.
__________________________________________________________________________ PSI/PercentTrial Formula Dose.sup.(1) Slump Air ROH Water Red. 3 Day 7 Days 28 Days__________________________________________________________________________0 Plain 0.88 6.75 5.1 Frozen 915 2206 4206 Micro-Air 0.88 6.75 100 100 1001 W 6.38 7.4 4.625 -12.3% 2548 4486 5787 278 203 1372 X 6.00 7.8 3.625 -15.8% 2693 4486 5898 294 203 1403 Y 0.58 6.50 5.5 5.125 -9.5% 2198 3722 5401 Micro-Air 240 169 1304 Z 0.66 6.30 5.8 5.875 -10.5% 2383 4373 5646 Micro-Air 260 198 1345 AA 0.35 6.25 5.9 6.5 -12.6% 2314 5051 7118 Micro-Air 253 229 1696 BB 6.25 6.9 6.0 -12.3% 2726 5146 6678 298 233 1597 CC 6.63 5.8 5.625 -10.5% 2512 4678 6196 275 212 1478 DD 0.40 6.50 5.3 6.750 -8.1% 2448 4558 5925 Micro-Air 268 207 14199 Plain 6.38 5.3 5.380 1125 2207 3962__________________________________________________________________________ Samples 0-8 were made at 35-40° F. cured at variable temperatures from 20-40° F. (3 Day Cure 20-33 F) Samples 99 (Plain) made and cured at 50° F. | A chloride-free admixture for use as a cold weather (e.g., 13° F. to 40° F.) concrete set accelerator. The admixtures comprise;
1) at least one soluble inorganic salt having freezing point depressant properties,
2) at least one water reducing dispersant, e.g., superplasticizer,
3) at least one inorganic early set and strength accelerator, and optionally,
4) at least one inorganic set accelerator. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119(a) on Patent Application No. 2008-174731 filed in Japan on Jul. 3, 2008, the entire contents of which are hereby incorporated by reference.
BACKGROUND
[0002] In power semiconductor devices used in power converters, power controllers, and the like, a switching element for on/off switching of current flow, such as a high breakdown voltage power transistor or the like is formed together with a control circuit and a protection circuit in a single substrate. This configuration achieves reduction in size and weight and high functionality, and therefore, are used in various fields of switching power supplies for various electronic equipment, such as office equipment, home appliances, and the like. The control circuit and the protection circuit are formed with an active element (e.g., a transistor element), a resistance element, a capacitive element, and the like.
[0003] The above power semiconductor devices are demanded to have a small voltage drop in an ON state for reducing power loss as far as possible Particularly, in the fields that requires high breakdown voltages, transistors employing a RESURF (Reduced Surface Field) structure are suitable.
[0004] As one example, the configuration and operation of a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) disclosed in Japanese Patent No. 2529717 will be described below.
[0005] FIG. 10 shows a cross sectional configuration of the RESURFMOSFET formed on a semiconductor substrate.
[0006] As shown in FIG. 10 , a semiconductor device 210 is formed using a semiconductor substrate 200 made of silicon (Si) of a first conductivity type.
[0007] In the upper portion of the semiconductor substrate 200 , a second conductivity type extension drain 201 is formed. A second conductivity type drain region 202 is formed in the surface portion of the drain extension region 201 .
[0008] In the surface portion of the semiconductor substrate 200 , a second conductivity type source region 203 is formed with the drain extension region 201 interposed between it and the drain region 202 , and with a predetermined distance left from the drain region 202 .
[0009] In the surface portion of a part of the drain extension region 201 which is located between the drain region 202 and the source region 203 , a first conductivity type buried region 204 electrically connected to the semiconductor substrate 200 is formed.
[0010] Further, a first conductivity type contact region 205 is formed in the surface portion of the semiconductor substrate 200 so as to be adjacent and electrically connected to the source region 203 . In the surface portion of the semiconductor substrate 200 , a first conductivity type well region 206 is also formed so as to surround the source region 203 and the contact region 205 and so as to be adjacent to the drain extension region 201 .
[0011] In addition, an insulating film 207 of a silicon oxide film is formed on a part of the well region 206 which is located between the drain extension region 201 and the source region 203 , and a gate electrode 208 made of polysilicon is formed thereon.
[0012] In the semiconductor device 210 thus configured, a voltage is applied between the drain region 202 and the source region 203 , and a voltage equal to or higher than a specified voltage is applied between the gate electrode 208 and the source region 203 so that the gate electrode 208 has a high potential. This forms a channel in a strong inversion state in a region of the well region 206 which is immediately below the gate electrode 208 , and accordingly, current flows between the drain region 202 and the source region 203 through the channel. Hereinafter, this state in which the current flows is called an ON state.
[0013] Further, in the semiconductor device 210 , when the voltage applied between the gate electrode 208 and the source region 203 is lower than the specified voltage, the channel disappears, and a reverse bias voltage is applied between the well region 206 and the drain extension region 201 . As a result, a pn junction is formed between the well region 206 and the drain extension region 201 , and the current does not flow between the drain region 202 and the source region 203 . Hereinafter, this state in which the current does not flow is called an OFF state.
[0014] Here, in the semiconductor device 210 shown in FIG. 10 , the buried region 204 is formed in a portion of the drain extension region 201 which is located between the source region 203 and the drain region 202 . For this reason, when a high voltage is applied between the drain region 202 and the source region 203 , a depletion region is formed around the junction interface between the buried region 204 and the drain extension region 201 additionally, at the same time when a depletion region is formed around the junction interface between the drain extension region 201 and the semiconductor substrate 200 .
[0015] Accordingly, in the configuration shown in FIG. 10 , even if the impurity concentration of the drain extension region 201 is increased, the depletion regions in the drain extension region 201 can be maintained when compared with a configuration with no buried region 204 . The depletion regions can absorb the potential difference between the drain region 202 and the source region 203 .
[0016] Thus, the semiconductor substrate 200 having the RESURFMOSFET structure shown in FIG. 10 can maintain a high breakdown voltage. Further, the increased impurity concentration of the extension region 201 can reduce the electric resistance (on-resistance) between the drain region 202 and the source region 203 .
SUMMARY
[0017] However, production of the semiconductor device 210 shown in FIG. 10 may result in devices having remarkably low surge capacities.
[0018] In view of this, a semiconductor device that can ensure both a desired breakdown voltage and a surge capacity will be described below.
[0019] The inventors first studied the reason why the surge capacity decreases.
[0020] FIG. 11 shows the relationship (a solid line) between the electric conductivity and the breakdown voltage of the drain extension region 201 including the buried region 204 , and the relationship (a broken line) between the electric conductivity and the surge capacity of the semiconductor device 210 , according to the research by the inventors. The surge capacity means a capacity tolerable toward the surge voltage generated at a switching between the ON state and the OFF state.
[0021] The electric conductivity herein is defined by the following relational expression, and serves as an index indicating a ratio between the impurity concentration of the drain extension region 201 and the impurity concentration of the buried region 204 .
[0000] Electric conductivity σ=1×10 3 ×(1/RSed−3/RSb) [μS (microsiemens)]
[0022] RSed: the sheet resistance of the drain extension region 201 including the buried region 204
[0023] RSb: the sheet resistance of the buried region 204 .
[0024] As shown in FIG. 11 , the breakdown voltage of the semiconductor device 210 depends on the electric conductivity of the drain extension region 201 . The breakdown voltage is a maximum when the electric conductivity is a predetermined value, and decreases as the electric conductivity deviates from the predetermined value.
[0025] Here, the electric conductivity is an index defined by the sheet resistances of the drain extension region 201 and buried region 204 , as described previously.
[0026] Accordingly, the relationship between the electric conductivity and the breakdown voltage indicated in FIG. 11 indicates that the breakdown voltage decreases as the impurity concentration of the drain extension region 201 and buried region 204 deviates from the predetermined value. For this reason, in the semiconductor device 210 , the impurity concentration of the drain extension region 201 and buried region 204 is adjusted so that the breakdown voltage of the semiconductor device 210 is a maximum.
[0027] In view of this, the present inventors studied in detail the relationship between the electric conductivity and the surge capacity, and found that, when the electric conductivity is decreased from the predetermined electric conductivity as a boundary at which the breakdown voltage is a maximum, the surge capacity of the semiconductor device 210 remarkably decreases. This is also shown in FIG. 11 .
[0028] This indicates that where the sheet resistance of the drain extension region 201 or the buried region 204 varies, in other words, where the impurity concentration of the drain extension region 201 or the buried region 204 varies, the surge capacity may remarkably decrease.
[0029] In view of the foregoing, a semiconductor device of the present disclosure includes: a first diffusion region of a second conductivity type formed in an upper portion of a semiconductor substrate of a first conductivity type; a second diffusion region formed in a surface portion of the first diffusion region; a third diffusion region of the second conductivity type formed at a part a predetermined distance spaced apart from the second diffusion region in the surface portion of the semiconductor substrate with the first diffusion region interposed between it and the second diffusion region; a fourth diffusion region of the first conductivity type formed adjacent to the third diffusion region in the surface portion of the semiconductor substrate and electrically connected to the third diffusion region; and a gate electrode formed on a part between the first diffusion region and the third diffusion region with an insulating film interposed, wherein an impurity concentration of the first diffusion region is set higher than an impurity concentration adjusted so that a depletion region extending from an junction interface between the first diffusion region and the semiconductor substrate extends to a part of the first diffusion region which is between the second diffusion region and the gate electrode when a voltage is applied to the second diffusion region.
[0030] In the above semiconductor device, as will be described blow, a high breakdown voltage can be maintained, and a decrease in the surge capacity, which is caused by variation in impurity concentration of the first diffusion region, can be suppressed.
[0031] Conventionally, the impurity concentration of the first diffusion region is defined as a concentration at which the depletion region extending from the junction interface between the first diffusion region and the semiconductor substrate is formed in the entirety of the dominant part of the first diffusion region (in a more specific example, a part of the first diffusion region which is between the second diffusion region and the gate electrode). This concentration is a concentration set so that application of a predetermined voltage to the second diffusion region in a state where the semiconductor device is turned off depletes the first diffusion region and removes the electrons and holes in the first diffusion region to allow the breakdown voltage of the semiconductor device to be a maximum. However, where the concentration is set in this way, variation in concentration may remarkably decrease the surge capacity, as indicated in FIG. 11 as a novel understanding by the present inventors.
[0032] In contrast, in the semiconductor device of the present disclosure, the impurity concentration of the first diffusion region is set higher than that in the conventional device. This can maintain, even if the impurity concentration of the first diffusion region varies, the impurity concentration can be maintained within the range where the dependency of the surge capacity on the impurity concentration is comparatively small, thereby preventing a remarkable decrease in surge capacity.
[0033] It is preferable that the impurity concentration of the first diffusion region is set higher than an impurity concentration adjusted so that the depletion region extending from the junction interface between the first diffusion region and the semiconductor substrate extends in an entirety of the first diffusion region.
[0034] This concentration setting can ensure the above advantages.
[0035] Further, it is preferable that the impurity concentration of the first diffusion region is set higher than an impurity concentration at which a breakdown voltage of the semiconductor device is a maximum.
[0036] As described above, the surge capacity may decrease remarkably by variation in concentration around the concentration at which the breakdown voltage of the semiconductor device is a maximum. Hence, the impurity concentration of the first diffusion region may be set in the concentration range higher than the above concentration.
[0037] Preferably, the impurity concentration of the first diffusion region is set higher than an impurity concentration at which a variation amount of a surge capacity of the semiconductor device with respect to a variation amount of the impurity concentration of the first diffusion region is small.
[0038] As described above, the present inventors found that a region where variation in surge capacity with respect to variation in impurity concentration is relatively large and a region where the variation in surge capacity is small when compared therewith are present in the vicinity of the concentration conventionally set as the impurity concentration of the first diffusion region. In view of this, the impurity concentration of the first diffusion region is set in a region higher than the impurity concentration at the boundary therebetween. This can suppress a remarkable decrease in surge capacity, which is caused by a decrease in impurity concentration.
[0039] The above semiconductor device of the present disclosure can be utilized in general semiconductor devices utilizing the RESURF structure. As examples, a MOS transistor and an insulated gate bipolar transistor (IGBT) will be referred to below.
[0040] That is, in the semiconductor deice of the present disclosure, it is preferable that a MOS transistor is formed which uses the first diffusion region as an drain extension region, the second diffusion region as a drain region of the second conductivity type, the third diffusion region as a source region, and the fourth diffusion region as a contact region.
[0041] The impurity concentration of the drain extension region of the above MOS transistor is set higher than the conventionally defined concentration. This increases the margin for variation in impurity concentration of the drain extension region for the surge capacity. That is, a semiconductor device including the MOS transistor can ensure the surge capacity with a high breakdown voltage maintained.
[0042] Alternatively, in the semiconductor device of the present disclosure, it is preferable that an insulated gate bipolar transistor is formed which uses the first diffusion region as a base region, the second diffusion region as a collector region of the first conductivity type, the third diffusion region as an emitter region, and the fourth diffusion region as a contact region.
[0043] In this IGBT, the impurity concentration of the base region is set higher than the conventionally defined concentration. This increases the margin for variation in impurity concentration of the base region for the surge capacity. That is, a semiconductor device including the IGBT can ensure the surge capacity with a high breakdown voltage maintained.
[0044] In the semiconductor device of the present disclosure, preferably, a MOS transistor and an insulated gate bipolar transistor are formed which use the first diffusion region as a base/drain extension region, the second diffusion region as a contact/drain region including a collector region of the first conductivity type and a drain region of the second drain region of the second conductivity type, the third diffusion region as an emitter/source region, and the fourth diffusion region as a contact region.
[0045] Thus, the second diffusion region has the structure including the first conductivity type region and the second conductivity type region electrically connected to each other, with a result that the above MOS transistor and IGBT can be incorporated in a single semiconductor device.
[0046] Referring to high breakdown semiconductor switching elements, reduction in power loss caused in operation is demanded in general. In detail, the use of a MOS transistor, which has a large electric resistance in operation, increases power loss in the ON state when compared with the use of an IGBT. In contrast, the use of an IGBT increases power loss at switching between the ON state and the OFF state when compared with the use of a MOS transistor.
[0047] In contrast, a structure in which a MOS transistor and a IGBT are incorporated in a single semiconductor device can result in utilization of the IGBT, which has a low electrical resistance, in usual operation and the MOS transistor, which is advantageous in power loss at switching, at switching between the ON state and the OFF state. As a result, the structure in which both of them are incorporated can reduce the power loss when compared with a structure including either one of the MOS transistor or the IGBT.
[0048] It is preferable that an electric conductivity of the first diffusion region is equal to or larger than 180 μS and equal to or smaller than 210 μS.
[0049] The electric conductivity of the first diffusion region depends on the impurity concentration of the first diffusion region. When the impurity concentration is set so that the electric conductivity of the first diffusion region in the semiconductor device of the present disclosure falls in the above range, it is possible to suppress a significant decrease in surge capacity caused by variation in impurity concentration, and to suppress to a minimum a decrease in breakdown voltage caused by setting the impurity concentration higher than the conventionally set impurity concentration.
[0050] Further, it is preferable to form at least one buried region of the first conductivity type within the first diffusion region.
[0051] This extends the depletion region from the junction interface between the first diffusion region and the buried region, in addition to the depletion region from the junction interface between the first diffusion region and the semiconductor substrate. Accordingly, even with the first diffusion region having the increased impurity concentration, depletion of the first diffusion region can be ensured. Particularly, the dominant part of the first diffusion region can be entirely depleted. This can achieve maintenance of a high breakdown voltage and a decrease in electric resistance in operation.
[0052] Preferably, multiple ones of the at least one buried region are arranged at regular intervals.
[0053] This can remarkably obtain the above advantages obtained by providing the buried layer.
[0054] Further, it is preferable to set an electric conductivity of the first diffusion region including the at least one buried region equal to or larger than 180 μS and equal to or smaller than 210 μS.
[0055] When the electric conductivity, which is determined according to the sheet resistance of the buried layer and the sheet resistance of the first diffusion region, falls in the above range, it is possible to suppress a remarkable decrease in surge capacity caused by variation in impurity concentration and to suppress a decrease in breakdown voltage caused by the increased impurity concentration higher than the conventionally set concentration.
[0056] As described above, according to the semiconductor device of the present disclosure, the margin for variation in manufacture can be extended, and a desired surge capacity can be ensured with the high breakdown voltage of a semiconductor switching element having a high breakdown voltage maintained.
BRIEF DESCRIPTION OF THE DRAWINGS
[0057] FIG. 1 is a schematic cross-sectional view showing a configuration of a semiconductor device in accordance with Example Embodiment 1.
[0058] FIG. 2 is a graph showing a relationship between the electric conductivity and the surge capacity in an extended drain region of the semiconductor device in accordance with Example Embodiment 1.
[0059] FIG. 3 is a graph showing a relationship between the electric conductivity and the breakdown voltage in the drain extension region of the semiconductor device in accordance with Example Embodiment 1.
[0060] FIG. 4 is a schematic cross-sectional view showing a configuration of a semiconductor device in accordance with Example Embodiment 2.
[0061] FIG. 5 is a schematic plan view showing a semiconductor device in accordance with Example Embodiment 3.
[0062] FIG. 6 is a schematic cross-sectional view showing a configuration of the semiconductor device in accordance with Example Embodiment 3, and shows a cross section taken along the line VI-VI′ in FIG. 5
[0063] FIG. 7 a schematic cross-sectional view showing a configuration of the semiconductor device in accordance with Example Embodiment 3, and shows a cross section taken along the line VII-VII′ in FIG. 5 .
[0064] FIG. 8 a schematic cross-sectional view showing a semiconductor device in accordance with Example Embodiment 4.
[0065] FIG. 9 is a schematic cross-sectional view showing a semiconductor device in accordance with a modified example of Example Embodiment 4.
[0066] FIG. 10 is a schematic cross-sectional view showing a conventional semiconductor device.
[0067] FIG. 11 is a graph showing relationships between the electric conductivity and the breakdown voltage or the surge capacity in an drain extension region of a conventional semiconductor device.
DETAILED DESCRIPTION
Example Embodiment 1
[0068] A semiconductor device in accordance with Example Embodiment 1 will be described below with reference to the drawings. FIG. 1 schematically shows a cross section of an example semiconductor device 150 , more specifically, a RESURFMOSFET structure formed on a semiconductor substrate.
[0069] As shown in FIG. 1 , the semiconductor device 150 of the present example embodiment is formed using a semiconductor substrate 100 made of P-type silicon (Si) having an impurity concentration of about 1×10 14 to 1×10 17 cm −3 .
[0070] In the surface portion of the semiconductor substrate 100 , an N-type drain extension region 101 and a P-type well region 102 are formed. The impurity concentration of the P-type well region 102 is about 1×10 16 to 1×10 17 cm 3 .
[0071] An N-type source region 103 having a high impurity concentration is formed in a part of the surface portion of the P-type well region 102 . A gate electrode 105 made of polysilicon is formed, with a gate oxide film 104 made of silicon oxide (SiO 2 ) interposed, on the surface of a part of the P-type well region 102 which is interposed between the N-type drain extension region 101 and the N-type source region 103 .
[0072] In the surface portion of the P-type well region 102 , a P-type contact region 106 is formed. The impurity concentration of the P-type contact region 106 is higher than that of the P-type well region 102 . A source electrode 107 made of an aluminum alloy, such as AlSiCu or the like is formed on and across the surface portions of the P-type contact region 106 and the N-type source region 103 . The source electrode 107 is electrically connected in common to the P-type contact region 106 and the N-type source region 103 .
[0073] In the surface portion of the N-type drain extension region 101 , an N-type drain region 108 is formed which has an impurity concentration higher than that of the N-type drain extension region 101 . The N-type drain region 108 is located on the opposite side of the gate electrode 105 to the N-type source region 103 . Further, a drain electrode 109 made of an aluminum alloy, such as AlSiCu or the like is formed on the N-type drain region 108 , and is electrically connected to the N-type drain region 108 .
[0074] In addition, isolations 110 a and 110 b (which may be collectively called an isolation 110 ) made of silicon oxide are formed in the surface portions of the N-type drain extension region 101 and the P-type well region 102 , respectively, for isolating the transistors formed on the semiconductor substrate 100 .
[0075] An interlayer insulating film 111 having a layered structure of silicon oxide and BPSG is formed so as to cover the N-type source region 103 , the gate electrode 105 , the P-type contact region 106 , the isolation 110 , and the like. The interlayer insulating film 111 electrically isolates the gate electrode 105 , the source electrode 107 , and the drain electrode 109 from one another. The drain electrode 109 and the source electrode 107 pass through the interlayer insulating film 111 .
[0076] On the interlayer insulating film 111 , a protection film 112 made of silicon nitride (SiN) is formed so as to cover the gate electrode 105 and the source electrode 107 .
[0077] Referring herein to a MOS transistor having the RESURF structure shown in FIG. 10 , the impurity concentration of the drain extension region 201 is set at a concentration at which the depletion region extending from the junction interface between the drain extension region 201 and the semiconductor substrate 200 is formed in the entirety of the dominant part of the drain extension region 201 . A further specific example of the concentration is a concentration at which the depletion region extends to a part of the drain extension region 201 which is between the drain region 202 and the gate electrode 208 . Because, setting at this concentration can make the breakdown voltage of a semiconductor device to be a maximum.
[0078] In contrast, in the semiconductor device 150 of the present example embodiment, the impurity concentration of the N-type drain extension region 101 is set higher than the impurity concentration at which the breakdown voltage of the semiconductor device is a maximum. Specifically, in the present example embodiment, the impurity concentration of the N-type drain extension region 101 is set at about 0.5×10 16 to 1.0×10 16 cm −3 . It is noted that, in the conventional semiconductor device, the impurity concentration of the drain extension region is set in a range of 0.2×10 16 to 0.4×10 16 cm −3 , for example.
[0079] FIGS. 2 and 3 show the relationship between the electric conductivity and the surge capacity and the relationship between the electric conductivity and the breakdown voltage, respectively, of the N-type drain extension region 101 of the semiconductor device 150 . It is noted that, as has been described previously, the electric conductivity is a value determined by the sheet resistance of the N-type drain extension region 101 , and serves as an index indicating the impurity concentration of the N-type drain extension region 101 .
[0080] Further, regions enclosed by the solid lines in FIGS. 2 and 3 indicate the electric conductivity range corresponding to the impurity concentration of the N-type drain extension region 101 in the present example embodiment. Here, the ranges are 180 μS or larger and 210 μS or smaller. In contrast, regions enclosed by the broken lines indicate the electric conductivity range corresponding to the impurity concentration that has been set conventionally.
[0081] As indicated in FIG. 2 , where the concentration is in the conventional range, variation in electrical conductivity of the N-type drain extension region 101 , which is caused by variation in manufacture and the like, may cause a remarkable decrease in surge capacity. In other words, the surge capacity may vary greatly in the conventional concentration range.
[0082] In contrast, in the case where the concentration range is set according to the present example embodiment, even if the impurity concentration of the N-type drain extension region 101 varies to cause variation in electric conductivity, a remarkable decrease in surge capacity cannot occur. This is because the concentration range is set in a range that can cause a comparatively small amount of variation in surge capacity, in view of the fact that a region where variation in surge capacity with respect to variation in impurity concentration is comparatively large and a region where the variation in surge capacity is small when compared therewith are present with a boundary drawn at a predetermined value. As a result, regardless of the presence of variation in impurity concentration, a high breakdown voltage can be maintained, and a desired surge capacity can be ensured.
[0083] In addition, as shown in FIG. 3 , the impurity concentration of the N-type drain extension region 101 within the above range can lead to suppression of a decrease in breakdown voltage, which is caused by the increased impurity concentration of the N-type drain extension region 101 , to a minimum.
[0084] As described above, according to the semiconductor device 150 of the present example embodiment, even if the impurity concentration of the N-type drain extension region 101 varies, a desired surge capacity can be ensured, while a high breakdown voltage can be maintained.
Example Embodiment 2
[0085] Example Embodiment 2 will be described below with reference to the drawing. FIG. 4 schematically shows a cross sectional configuration of an example semiconductor device 151 in Example Embodiment 2. The semiconductor device 151 is an IGBT in a horizontal structure formed on a semiconductor substrate.
[0086] As shown in FIG. 4 , the semiconductor device 151 has a structure similar to that of the semiconductor device 150 in FIG. 1 . Therefore, only different points are described in detail, and further detailed description of the same components as those in FIG. 1 is omitted by putting the same reference numerals.
[0087] First, in FIG. 4 , a P-type collector region 115 is formed, in place of the N-type drain region 108 in FIG. 1 , in the surface portion of the N-type drain extension region 101 . The impurity concentration of the P-type collector region 115 is higher than that of the N-type drain extension region 101 . In place of the drain electrode 109 in FIG. 1 , a collector electrode 116 made of an aluminum alloy, such as AlSiCu, or the like is formed on the P-type collector region 115 .
[0088] Further, components of the semiconductor device in FIG. 4 corresponding to the N-type source region 103 and the source electrode 107 in FIG. 1 are called an emitter region 113 and an emitter electrode 114 , respectively. That is, only the names are different.
[0089] In the semiconductor device 151 , in the ON state, electron current flows from the emitter region 113 to the N-type drain extension region 101 , and this current serves as base current of a pnp transistor formed with the P-type contact region 106 , the N-type drain extension region 101 , and the P-type collector region 115 . When the base current flows, a large amount of holes are injected from the P-type collector region 115 to the N-type drain extension region 101 . Accordingly, electrons are also injected from the emitter region 113 to the N-type drain extension region 101 for satisfying charge neutrality. Accordingly, both the electron density and the hole density of the N-type drain extension region 101 increase to remarkably reduce the on-resistance between the P-type collector region 105 and the emitter region 113 .
[0090] Similarly to the case in Example Embodiment 1, setting the impurity concentration of the N-type drain extension region 101 higher than that in the conventional device can avoid a decrease in surge capacity.
[0091] Thus, the semiconductor device 151 in the present example embodiment, which is an IGBT in a horizontal structure, can also ensure a high breakdown voltage and a desired surge capacity. In addition, the on-resistance can be further reduced when compared with the semiconductor device 150 of Example Embodiment 1.
Example Embodiment 3
[0092] Example Embodiment 3 will be described below with reference to the drawings. FIG. 5 to FIG. 7 show a configuration of an example semiconductor device 152 of the present example embodiment. The semiconductor device 152 has, on a single semiconductor substrate, a structure on which MOS transistors in a horizontal structure having a cross section schematically shown in FIG. 6 and IGBTs in a horizontal structure having a cross section schematically shown in FIG. 7 are arranged alternatively as shown in a plan view of FIG. 5 . FIG. 6 shows a cross section taken along the line VI-VI′ in FIG. 5 , and FIG. 7 shows a cross section taken along the line VII-VII′ in FIG. 5 .
[0093] Here, the configuration of the MOS transistors shown in FIG. 6 is the same as that of the semiconductor device 150 of Example Embodiment 1 shown in FIG. 1 , and the configuration of the IGBTs shown in FIG. 7 is the same as that of the semiconductor device 151 of Example Embodiment 2 shown in FIG. 4 .
[0094] It is noted that the N-type source region 103 in FIG. 1 and the emitter region 113 in FIG. 4 correspond to an emitter/source region 117 formed across the MOS transistors and the IGBTs arranged alternatively. In place of the source electrode 107 and the emitter electrode 114 , an emitter/source electrode 118 is formed as an electrode formed on and connected in common to the emitter/source region 117 and the P-type contact region 106 .
[0095] The N-type drain regions 108 and P-type collector regions 115 having an impurity concentration higher than that of the N-type drain extension region 101 are the same as those shown in FIGS. 1 and 4 , respectively. However, as shown in FIG. 5 , the N-type drain regions 108 and the P-type collector regions 115 in the semiconductor device 152 of the present example embodiment are arranged alternatively in a direction of the principal plane of the semiconductor substrate 100 , and a corrector/drain electrode 119 is formed so as to electrically connect them to each other. The collector/drain electrode 119 is made of an aluminum alloy, such as AlSiCu or the like.
[0096] To components except the above described components, the same reference numerals are assigned as those in FIGS. 1 and 4 , and no detailed description will be given herein.
[0097] As shown in FIGS. 5 to 7 , in the semiconductor device 152 of the present example embodiment, the N-type drain regions 108 and the P-type collector regions 115 are formed in the surface portion of the N-type drain extension region 101 so as to be electrically connected to each other through the collector/drain electrode 119 . In this way, two kinds of transistors of the MOS transistors and the IGBTs in the RESURF structures, which are electrically connected to each other in parallel, are incorporated.
[0098] Accordingly, the semiconductor device 152 can selectively utilize the IGBTs, which are advantageous in power loss in a conduction state, in the normal ON state, and the MOS transistors, which are advantageous in power loss at switching, at switching between the ON state and the OFF state.
[0099] As a result, the semiconductor device 152 of the present example embodiment can reduce the power loss when compared with both the semiconductor device 150 of Example Embodiment 1 and the semiconductor device 151 of Example Embodiment 2.
[0100] In addition, similarly to the case of Example Embodiment 1, a decrease in surge capacity can be avoided by setting the impurity concentration of the N-type drain extension region 101 higher than the conventionally set concentration.
Example Embodiment 4
[0101] Example Embodiment 4 will be described with reference to the drawing. FIG. 8 schematically shows a cross-sectional configuration of an example semiconductor device 153 of the present example embodiment.
[0102] The semiconductor device 153 shown in FIG. 8 has a configuration in which a P-type buried region 120 formed in the surface portion of the N-type drain extension region 101 is added to the semiconductor device 150 of Example Embodiment 1 shown in FIG. 1 . The P-type buried region 120 has a thickness of about 1.0 μm, and an impurity concentration in a range of about 1×10 16 to 1×10 17 cm −3 . Further, the P-type buried region 120 is electrically connected to the semiconductor substrate 100 , and is formed so as to extend substantially in parallel to the principal plane of the semiconductor substrate 100 .
[0103] The other components are the same as those shown in FIG. 1 . Therefore, the same reference numerals are used, and no detailed description will be given here.
[0104] According to the semiconductor device 153 in FIG. 8 , by forming the P-type buried region 120 in the surface portion of the N-type drain extension region 101 , application of a high voltage between the drain electrode 109 and the source electrode 107 in the OFF state causes a depletion region from the junction interface between the N-type drain extension region 101 and the P-type buried region 120 to extend, in addition to a depletion region from the junction interface between the N-type drain extension region 101 and the semiconductor substrate 100 . This can result in depletion of the entire N-type drain extension region 101 even with the increased impurity concentration of the N-type drain extension region 101 . As a result, the depletion region can absorb the potential difference between the drain electrode 109 and the source electrode 107 .
[0105] Hence, in the semiconductor device 153 of the present example embodiment, the impurity concentration of the N-type extension region 101 can be set higher than that in the semiconductor device 150 of Example Embodiment 1, thereby reducing the electric resistance in operation.
[0106] Referring to a modified example of the present example embodiment, as shown in FIG. 9 , the P-type buried region 120 may be formed in a part of the N-type drain extension region 101 which is located at a predetermined depth from its surface, rather than the surface portion of the N-type drain extension region 101 . Accordingly, the area of the contact face between the N-type drain extension region 101 and the P-type buried region 120 can be increased. This can encourage extension of the depletion regions from the junction interfaces in applying a high voltage between the drain electrode 109 and the source electrode 107 in the OFF state. As a result, in a semiconductor device 153 shown in FIG. 9 , the impurity concentration of the N-type extension region 101 can be set higher than that in the semiconductor device 153 shown in FIG. 8 , thereby further reducing the electric resistance.
[0107] In another example embodiment, a plurality of P-type buried regions 120 electrically connected to the semiconductor substrate 100 may be formed at predetermined regular intervals in the N-type drain extension region 101 . This can provide a further increased impurity concentration of the N-type drain extension region 101 , thereby further reducing the electric resistance.
[0108] In addition, in the present example embodiment, in the case where the impurity concentration of the P-type buried region 120 is 3.0×10 16 cm −3 , for example, the impurity concentration of the N-type drain extension region 101 is preferably 2.0×10 16 cm −3 or higher and 2.1×10 16 cm −3 or lower. By doing so, the electric conductivity of the N-type drain extension region 101 can be set in a range of 180 μS to 210 μS. It is noted that the impurity concentration of an N-type drain extension region in a conventional semiconductor device having a similar configuration is in a range from 2.3×10 16 to 2.5×10 16 cm −3 .
[0109] Hence, as shown in FIGS. 2 and 3 , a lowering of the breakdown voltage of the semiconductor device, which is caused by increasing the impurity concentration of the N-type drain extension region 101 higher than a predetermined concentration, can be suppressed to a minimum.
[0110] Moreover, the present example embodiment refers to the case where the P-type buried region 120 is added to the semiconductor device 150 of Example Embodiment 1. However, the same advantages can be obtained by forming the P-type buried region 120 within the N-type drain extension region 101 in the semiconductor device 151 of Example Embodiment 2 and the like. | A semiconductor device includes a first diffusion region of a second conductivity type formed in an upper portion of a semiconductor substrate of a first conductivity type, a second diffusion region formed in a surface portion of the first diffusion region, a third diffusion region of the second conductivity type formed a predetermined distance spaced apart from the second diffusion region in the surface portion of the semiconductor substrate, a fourth diffusion region of the first conductivity type formed adjacent to the third diffusion region and electrically connected to the third diffusion region, a gate electrode formed on a part between the first diffusion region and the third diffusion region, and an insulating film formed thereon. The impurity concentration of the first diffusion region is set higher than an impurity concentration at which a depletion region extending from an junction interface between the first diffusion region and the semiconductor substrate is formed in a part of the first diffusion region which is between the second diffusion region and the gate electrode when a voltage is applied to the second diffusion region. | 7 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] The present invention claims priority to its priority document No. 2002-307461 filed in the Japanese Patent Office on Oct. 22, 2002, the entire contents of which being incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a novel recording media drive apparatus, and particularly relates to technology enabling straightforward changing of a front panel that covers the front side of a body equipped with means for writing and/or reading a signal to/from a recording media and has an insertion/removal opening for inserting and removing the recording media.
[0004] 2. Description of Related Art
[0005] Various recording media drive apparatuses such as flexible disc drive apparatuses, optical disc drive apparatuses, and magneto-optical disc drive apparatuses etc. are employed as external storage devices in information processing apparatus such as personal computers etc.
[0006] The overall dimensions etc. of these types of recording media drives are standardized to enable a user to exchange or expand such devices themselves. This also enables a so-called “build-it-yourself” approach where a user starts with a motherboard, then assembles a personal computer by selecting the desired built-in peripheral apparatus.
[0007] For example, a space, referred to as a “bay”, for housing built-in peripheral apparatus, is prepared at a body of a personal computer, with it then being possible to install desired peripheral apparatus at a desired bay. The fronts of bays that are to house removable recording media drive apparatuses are provided with openings to enable access from outside of the body and the openings are covered over by covers. When a new removable recording media drive apparatus is mounted, the cover is removed and the front of the recording media drive apparatus installed in the bay is made to face to outside of the body so that it is possible to insert/remove the recording media.
[0008] The recording media drive apparatus includes signal writing means for writing signals to the recording media within the body and/or signal reading means for reading signals. The front of the body is covered by a front panel having an insertion/removal opening for insertion and removal of the recording media into and out of the body. The front panel is therefore exposed at the front of the body of information processing apparatus such as a personal computer when a recording media drive apparatus is installed in a bay in the above manner.
[0009] In the case of expanding or exchanging the recording media drive apparatus at the information processing apparatus, the appearance of the information processing apparatus will deteriorate if the color or design of the front panel of the exchanged or expanded recording media drive apparatus does not match with the body of the information processing apparatus or with the color or design of existing peripheral apparatus.
[0010] It has therefore been considered to make the front panel freely detachable from the body (refer to patent document 1), and to prepare several front panels of different designs and colors to make it possible to select a front panel corresponding to a body of information processing apparatus which is to be installed to and to existing peripheral apparatus.
[0011] Patent Document 1
[0012] Japanese Patent Laid-open Publication No. 3-185899 (FIG. 1, FIG. 2, page 2).
SUMMARY OF THE INVENTION
[0013] Here, one end of front panel (of option block ( 2 )) shown in patent document 1 hooks into a body (refer to part A of FIG. 2) and the other end is fixed using a screw 3 . Parts and tools (a screwdriver) other than the front panel and body are therefore necessary in order to fix the front panel. The front panel therefore cannot be changed in a straightforward manner.
[0014] There is therefore a need to be able to change a front panel in a straightforward manner without requiring tools or spare parts.
[0015] In order to resolve the aforementioned problems, in the recording media drive apparatus of the present invention, a front panel is supported in a freely detachable manner through engagement with a body housing signal writing means for writing signals to a recording media and/or signal reading means for reading signals from the recording media. The engagement is achieved by causing the front panel to move towards the body. Force causing the front panel to move in a direction away from the body acts in a direction causing release of the engagement.
[0016] Engagement of the front panel and the body is therefore achieved in the recording media drive apparatus of the present invention simply by moving the front panel towards the body. Engagement of the front panel and the body is then released simply by moving the front panel in a direction away from the body.
[0017] A recording media drive apparatus according to a first aspect of the present invention is characterized by including: a body; signal writing means for writing a signal to a recording media and/or signal reading means for reading a signal, provided within the body; and a front panel covering the front of the body and having an insertion/removal opening for inserting and removing the recording media to and from the body. The front panel is supported in a freely detachable manner as a result of engagement with the body. The engagement is achieved by moving the front panel towards the body, and a force to move the front panel in a direction away from the body acts in a direction releasing the engagement.
[0018] Accordingly, in the recording media drive apparatus according to the first aspect of the present invention, the engagement of the front panel and the body may be achieved by simply moving the front panel toward the body, and the engagement of the front panel and the body may be released by moving the front panel away from the body. It is therefore possible to attach and detach the front panel to and from the body in a straightforward manner without using tools and without using parts other than the front panel and the body and the front panel can therefore be changed as desired.
[0019] With a recording media drive apparatus according to the second aspect of the present invention, engagement is achieved by mutual engagement of engaging holes provided at one of the front panel and the body and engaging projections provided at the remaining one of the front panel and the body. Further, an inclined surface is formed at the engaging projection or at an edge of an opening of the engaging hole so as to cause the engaging projection or the engaging hole to move in a direction away from the engaging hole or the engaging projection as a result of applying force to cause the front panel to move in a direction away from the body. A structure for attaching and detaching a front panel to and from a body in a straightforward manner without using tools and without using parts other than the front panel and the body may therefore easily be constructed.
[0020] A recording media drive apparatus according to the third aspect of the present invention includes a slider and an eject button. The slider is provided within the body, and induces an eject motion for ejecting the recording media installed within the body from the insertion/removal opening as a result of pushing from the front. The eject button projects forwards from the front panel that is fitted in a freely detachable manner as a result of engagement with the slider. Engagement is achieved as a result of causing the eject button to move towards the slider, and force causing the eject button to move in a direction away from the slider acts in a direction releasing the engagement. Attaching and detaching of the eject button to and from the slider can therefore be achieved without using any tools and without requiring any parts other than the eject button and the slider and the eject button can be changed as desired.
[0021] With a recording media drive apparatus according to the fourth aspect of the present invention, engagement is achieved by mutual engagement of engaging holes provided at one of the eject button and the slider and engaging projections providing at the remaining one of the eject button and the slider. Further, an inclined surface is formed at the engaging projection or the engaging hole so as to cause the engaging projections or the engaging holes to move in a direction away from the engaging holes or the engaging projections as a result of applying force to cause the eject button to move in a direction away from the slider. It is therefore possible to construct a structure for attaching and detaching an eject button to and from a slider in a straightforward manner without having to use tools and without having to use parts other than the eject button and slider.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The above and other objects, features and advantages of the present invention will become more apparent from the following description of the presently preferred exemplary embodiment of the invention taken in conjunction with the accompanying drawing, in which:
[0023] [0023]FIG. 1 shows an embodiment of a recording media drive apparatus of the present invention and is a perspective view showing both a recording media drive apparatus and a recording media cartridge;
[0024] [0024]FIG. 2 is a perspective view showing essential parts of a state where engagement of one side part of a display panel with a body is released;
[0025] [0025]FIG. 3 is a perspective view showing essential parts with a front panel removed from a body;
[0026] [0026]FIG. 4 is an exploded perspective view showing essential parts of a mechanism for inserting and removing a recording media;
[0027] [0027]FIG. 5 is an enlarged cross-sectional view of essential parts showing a situation of attaching and detaching a frront panel to and from a body;
[0028] [0028]FIG. 6 is an enlarged cross-sectional view of essential parts showing a further example of a method for attaching and detaching a front panel to and from a body;
[0029] [0029]FIG. 7 is an enlarged cross-sectional view of essential parts showing a situation of attaching and detaching an eject button to and from a slider;
[0030] [0030]FIG. 8 is a plan view of essential parts showing a situation of attaching and detaching an eject button to and from a slider;
[0031] [0031]FIG. 9 is a cross-sectional view of essential parts for illustrating, together with FIG. 10 and FIG. 11, an operation from installation to ejection of a recording media cartridge to and from a recording media drive apparatus, and shows a situation where the recording media cartridge is midway through being inserted into the recording media drive apparatus;
[0032] [0032]FIG. 10 is a view showing a situation at the instant where the recording media cartridge is inserted to the back of the cartridge holder;
[0033] [0033]FIG. 11 is a view showing a situation where the recording media cartridge is installed in the recording media drive apparatus;
[0034] [0034]FIG. 12 is across-sectional view of essential parts showing a modified example of an engaging structure for a body and a front panel; and
[0035] [0035]FIG. 13 is across-sectional view of essential parts showing a modified example of an engaging structure for a slider and an eject button.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] The following is a description with reference to the attached drawings of a preferred embodiment of a recording media drive apparatus of the present invention. The following shows a preferred embodiment of the present invention as applied to a flexible disc drive apparatus but the present invention may also be applied to, for example, various recording media drive apparatuses such as optical disc devices or magneto-optical disc drives, etc.
[0037] [0037]FIG. 1 shows the external appearance of a flexible disc drive apparatus 1 that is a recording media drive apparatus of this embodiment.
[0038] The flexible disc drive apparatus 1 includes a body 2 containing signal writing means and signal reading means (not shown) for writing and reading signals to and from a flexible disc. The front of the body 2 is covered with a front panel 3 . Other types of recording media drive apparatuses may be equipped only with signal reading means and not with signal recording means. It should be noted that the expression “A and/or B” used in this specification is used to selectively indicate the concept of “A and B” or “A or B”.
[0039] The front panel 3 has a rectangular shape elongated in lateral direction and is formed of synthetic resin. A laterally-elongated insertion/removal opening 4 is formed at the front panel 3 and a cover 5 is provided for opening and closing the insertion/removal opening 4 . As can be understood from FIG. 3 and FIG. 9 to FIG. 11, the cover 5 is a plate shape that is larger than the insertion/removal opening 4 . Two notches 6 , 6 are formed at an upper edge of the cover 5 spaced to the left and right so as to sandwich a central part in a horizontal direction, with shafts 7 , 7 being provided projecting from side edges at around the centers of the notches 6 , 6 . Two support brackets 8 , 8 are provided spaced to the left and right at positions from the upper edge of the back of the front panel 3 and support holes 8 a , 8 a are formed in the support brackets 8 , 8 . The shafts 7 , 7 of the cover 5 are passed through the support holes 8 a , 8 a so as to be rotatable and so as to ensure that the cover 5 is supported in a freely rotatable manner at the front panel 3 . The cover 5 is urged in a closing direction by a torsion coil spring 9 . A coiled part 9 a of the torsion coil spring 9 fits around one of the shafts 7 of the cover 5 and one arm part 9 b of the torsion coil spring 9 makes forcible contact with the back of the cover 5 . A remaining arm part 9 c of the torsion coil spring 9 makes forcible contact with a lower surface of an upper edge part 3 a projecting slightly to the rear from the upper edge of the front panel 3 . As a result, the cover 5 is urged in a closing direction so as to close the insertion/removal opening 4 of the front panel 3 from the back.
[0040] A laterally elongated rectangular button insertion hole 10 is formed below the portion where the insertion/removal opening 4 of the front panel 3 is formed.
[0041] As can be understood from FIG. 2 and FIG. 3, two pairs of left and right engaging pieces 11 , 11 , . . . are provided to as to face to the rear from positions to upper and lower ends of both left and right side edges of the front panel 3 , with engaging projections 12 , 12 , . . . being provided at outer surfaces of ends of the engaging pieces 11 , 11 . . . . As is understood from FIG. 5, the engaging projections 12 are triangular in shape when viewed from above and have inclined surfaces 12 a and 12 b to the front and rear, respectively. Namely, the top-side inclined surface 12 a is formed so as to become closer to the engaging piece 11 when going towards the end side at the end side of the engaging piece 11 and an base-side inclined surface 12 b is formed on a base side, i.e. on the side near to the front panel 3 , so as to become closer to the engaging piece 11 as the base is approached.
[0042] As can be understood from FIG. 1 to FIG. 3 and FIG. 5, engaging holes 13 , 13 , . . . are formed at positions to the upper and lower ends of front ends of side walls 2 a , 2 a of the body 2 .
[0043] The front panel 3 is fitted to the body 2 so as to cover a front opening of the body 2 as a result of the engaging projections 12 , 12 , . . . of the engaging pieces 11 , 11 . . . engaging with the engaging holes 13 , 13 , . . . of the body 2 . A description is now given with reference to FIG. 5 of fitting the front panel 3 to the body 2 .
[0044] First, the front panel 3 is brought close to the body 2 so that the height of the engaging pieces 11 , 11 , . . . of the front panel 3 becomes the same as the height of the engaging holes 13 , 13 , . . . of the body 2 (refer to FIG. 5( a )). The top-side inclined surfaces 12 a , 12 a , . . . at the sides of the ends of the engaging projections 12 , 12 , . . . provided at the ends of the engaging pieces 11 , 11 , . . . then come into contact with front ends of side walls 2 a , 2 a , . . . of the body 2 (refer to FIG. 5( b )). Only a side wall 2 a for one side of the body 2 , one engaging hole 13 , and one engaging piece 11 are shown in FIG. 5.
[0045] When the front panel 3 moves to the side of the body 2 i.e. in the direction of an arrow R in FIG. 5( c ) from the state shown in FIG. 5( b ), the top-side inclined surface 12 a at the end side slides smoothly along the front end of the side wall 2 a . The end of the engaging piece 11 is therefore subjected to force in a direction shown by an arrow CCW in FIG. 5( c ), causing the engaging piece 11 to flex (refer to FIG. 5( c )). As a result of the flexing of the engaging piece 11 in the direction CCW of the arrow in FIG. 5( c ), the engaging projection 12 slides smoothly along the inner surface of the side wall 2 a of the body 2 so that the front panel 3 moves in the direction of the arrow R in FIG. 5( c ).
[0046] When the engaging projection 12 reaches the position of the engaging hole 13 , the engaging piece 11 that was flexed in the direction of the arrow CCW in FIG. 5( c ) returns to its original state. The engaging projection 12 then engages with the engaging hole 13 so as to fit the front panel 3 to the body 2 in such a manner as to cover the front of the body 2 .
[0047] The front panel 3 is fitted to the body 2 so as to cover the front of the body 2 as a result of the engaging projections 12 , 12 , . . . of the front panel 3 engaging with the engaging holes 13 , 13 , . . . of the body 2 .
[0048] When removing the front panel 3 from the body 2 , when a force is fairly firmly applied so as to move the front panel 3 forwards, i.e. in the direction of arrow F in FIG. 5( e ), the base-side inclined surface 12 b on the base side of the engaging projection 12 slides smoothly along a front side edge 13 a of the engaging hole 13 . The end of the engaging piece 11 is therefore subjected to force so as to move in the direction of arrow CCW in FIG. 5( e ) so as to flex (refer to FIG. 5( e )).
[0049] Engagement of the engaging projection 12 with the engaging hole 13 is therefore released as a result of the flexing of the end of the engaging piece 11 in the direction of the arrow CCW in FIG. 5( e ). As a result, the engaging projection 12 can slide smoothly along the inside surface of the side wall 2 a of the body 2 in the direction of the arrow F and the front panel 3 can be removed from the body 2 .
[0050] The front panel 3 can be attached to and detached from the body 2 using a different method to the method shown in FIG. 5.
[0051] When the front panel 3 is fitted to the body 2 , first, engaging projections 12 , 12 of the engaging pieces 11 , 11 formed on one side of the front panel 3 are made to engage in advance with engaging holes 13 , 13 formed in a side wall 2 a on one side of the body 2 . The top-side inclined surfaces 12 a , 12 a on the end side of the engaging projections 12 , 12 of the engaging pieces 11 , 11 formed on the other side of the front panel then make contact with the front end of the side wall 2 a on the other side of the body 2 (refer to the solid lines in FIG. 6).
[0052] The side of the other side of the front panel 3 is then pushed in from the state shown by the solid line in FIG. 6 (refer to arrow R in FIG. 6). The top-side inclined surfaces 12 a , 12 a at the ends of the engaging projections 12 , 12 at the other side then slide smoothly at the front end of the side wall 2 a of the body 2 , the portions on which the engaging projections 12 , 12 are formed are subjected to force causing movement in the direction of arrow CCW, and the engaging pieces 11 , 11 are flexed. The engaging projections 12 , 12 then move smoothly to the rear along the inner surface of the side wall 2 a (refer to the single-dotted-and-dashed line of FIG. 6).
[0053] When the engaging projections 12 , 12 for the other side reach the positions of the engaging holes 13 , 13 of the other side, the engaging projections 12 , 12 engage with the engaging holes 13 , 13 and the front panel 3 is fitted to the body 2 (refer to the double-dotted-and-dashed line of FIG. 6).
[0054] When the front panel 3 is removed from the body, force is exerted so that the other side of the front panel 3 is dragged out from the body, i.e. force is exerted in the direction of arrow F in FIG. 6. The base-side inclined surfaces 12 b , 12 b on the base side of the engaging projections 12 , 12 on the other side therefore move smoothly at side edges 13 a , 13 a of the engaging holes 13 , 13 , the engaging pieces 11 , 11 flex in the direction of the arrow CCW, and the engaging pieces 11 , 11 come away from the body 2 via the state shown by the single-dotted-and-dashed line. It is therefore possible to remove the front panel 3 from the body 2 .
[0055] The front panel 3 can easily be fitted to the body 2 simply by lining up the front panel 3 and pushing the front panel 3 towards the body 2 . Further, the front panel 3 can also be easily detached from the body 2 simply by applying force so as to pull the front panel 3 away from the body 2 . There is also no requirement for any kind of parts other than the front panel 3 and the body 2 to attach and detach the body 2 to and from the front panel 3 .
[0056] A change can therefore easily be made to a desired front panel by preparing various types of front panel 3 that match with the body 2 .
[0057] At the flexible disc drive apparatus 1 , a flexible disc cartridge 14 (refer to FIG. 1, hereinafter referred to as “cartridge”) housing a flexible disc 14 a , that is a disc-shaped magnetic disc, in a rotatable manner is installed in the body 2 via the insertion/removal opening 4 of the front panel 3 so that writing and reading of signals to and from the flexible disc 14 a installed within the cartridge 14 can be carried out. When writing and/or reading of signals to and from the flexible disc 14 a is complete, the cartridge 14 is ejected from within the body 2 . The flexible disc drive apparatus 1 includes a slider 16 to induce the eject motion and an eject button 15 to push the slider.
[0058] As can be understood from FIG. 1 and FIG. 9 to FIG. 11, the eject button 15 is inserted through the button insertion hole 10 formed in the front panel 3 so that a front end of the eject button 15 projects towards the front from the front panel 3 . The slider 16 is provided within the body 2 in order to control installation and ejection of the cartridge 14 . The eject button 15 is fitted to the front end of the slider 16 and moves together with the slider.
[0059] As can be understood from FIG. 4, the slider 16 is integrally formed from a bottom plate 17 and side plates 18 , 18 projecting upwards from the left and right side edges of the bottom plate 17 . Two slits 19 , 19 , . . . are formed to the front and rear of both the left and right side plates 18 , 18 . Each slit 19 has a horizontal part 19 a positioned to the upper end of each side plate 18 and extending horizontally, and an inclined part 19 b extending downwards from the rear end of the horizontal part 19 a . A positioning slit 20 is formed positioned close to one side of the bottom plate 17 extending in a direction from front to back and a spring peg 21 is formed next to the rear end of the positioning slit 20 .
[0060] As can be understood from FIG. 7, a button support piece 22 is provided facing towards the front at a position by one side part of a front edge of the bottom plate of the slider 16 . A front piece is formed projecting downwards from the front end of a main piece 22 a extending towards the front of the button support piece 22 . The width of the front piece 22 b is slightly less than the width of the main piece 22 a so as to form engaging edges 22 c , 22 c at both side edges of the main piece 22 a . An engaging projection 23 is formed so as to project upwards at a substantially central part of the main piece 22 a . The engaging projection 23 is a trapezoidal shape as viewed from the side and has a central horizontal part 23 a , a front-side inclined surface 23 b extending downwards from the end of the horizontal part 23 a , and a rear-side inclined surface 23 c extending downwards to the rear from the rear end of the horizontal part 23 a.
[0061] As can be understood from FIG. 4, a chassis 24 is fixed within the body 2 and the slider 16 is supported at the chassis 24 in such a manner as to be capable of movement in a direction from front to back. The chassis 24 includes a bottom part 25 and side parts 26 , 26 projecting upwards from side edges of the bottom part 25 . A spring peg 25 a is formed projecting upwards at a position to the front end of the bottom part 25 , and guide slits 26 a , 26 a extending vertically are formed at a substantially central part in a direction from the front to the rear of the side parts 26 , 26 .
[0062] The slider 16 is supported at the chassis 24 by means (not shown) in such a manner as to be freely moveable in a direction from front to back. A tensioning coil spring 27 is installed across the spring peg 21 of the slider 16 and the spring peg 25 a of the chassis 24 . This ensures that the chassis 24 is urged towards the front, i.e. in the direction of arrow F in FIG. 4. The tensioning coil spring 27 is arranged within the positioning slit 20 formed at the bottom plate 17 of the slider 16 .
[0063] As can be understood from FIG. 4 and FIG. 9 to FIG. 11, a cartridge holder 28 supporting the cartridge 14 and moving up and down is supported at the chassis 24 in a manner enabling up and down movement. The cartridge holder 28 is integrally formed from a top plate 29 , side plates 30 , 30 projecting downwards from both side edges of the top plate 29 , and buttresses 31 , 31 projecting in directions towards each other from lower edges of the side plates 30 , 30 . Guide pieces 30 a , 30 a project to the sides from upper ends of central parts of the side plates 30 , 30 in a direction from front to back. Guide pins 30 b , 30 b project to the sides at positions to each end to both the front and rear of the side plates 30 . The guide pieces 30 a , 30 a of the cartridge holder 28 engage with the guide slits 26 a , 26 a of the chassis 24 in a freely slideable manner. This enables the cartridge holder 28 to move in only a vertical direction. The guide pins 30 b , 30 b . . . of the cartridge holder 28 engage with the slits 19 , 19 , . . . of the slider 16 in a freely slideable manner. This means that the cartridge holder 28 moves in an up and down direction as the slider 16 moves in a direction to the front and rear.
[0064] As can be understood from FIG. 3, FIG. 7 and FIG. 8, the eject button 15 is formed from synthetic resin and is integrally formed from a button part 32 and a coupling part 33 projecting to the rear from the rear end of the button part 32 . The button part 32 is a block-shape of a size capable of being passed through the button insertion hole 10 of the front panel 3 . The coupling part 33 includes an upper surface part 33 a , and side surface parts 33 b , 33 b ′ projecting downwards from left and right side parts of the upper surface part 33 a . An engaging hole 34 is formed at a substantially central part of the upper surface part 33 a , and engaging grooves 35 , 35 extending in a direction from front to back and reaching a rear end are formed at mutually facing surfaces of the side surface parts 33 b , 33 b ′. The side surface part 33 b of the side surface parts 33 b , 33 b ′ is formed to be substantially half the length of the upper surface part 33 a . However, the remaining side surface part 33 b is formed up to close to the end of the upper surface part 33 a . A slit 33 c is formed between the other side surface part 33 b and the upper surface part 33 a to give the upper surface part 33 a flexibility.
[0065] The eject button 15 is fitted to the slider 16 in the following manner.
[0066] First, the position of the eject button 15 is lined up with respect to the button support piece 22 of the slider 16 in such a manner that the heights of the engaging grooves 35 , 35 of the eject button 15 are the same as the heights of engaging edges 22 c , 22 c of the button support piece 22 of the slider 16 (refer to FIG. 7( a ), FIG. 8( a )).
[0067] When the eject button 15 is moved towards the slider 16 , i.e. in a direction shown by arrow R in FIG. 7( b ) from a state where the position of the eject button 15 is aligned with respect to the button support piece 22 , engaging edges 22 c , 22 c of the button support piece 22 engage with the engaging grooves 35 , 35 of the eject button 15 (refer to FIG. 7( b ), FIG. 8( c )). As shown in FIG. 8( b ), when the eject button 15 does not face the button support piece 22 , the engaging edges 22 c , 22 c of the button support piece 22 do not engage with the engaging grooves 35 , 35 of the eject button 15 .
[0068] When the eject button 15 is made to move in the direction shown by the arrow R in FIG. 7( c ) from the state shown in FIG. 7( b ) and FIG. 8( c ), the end of the upper surface part 33 a of the eject button 15 makes contact with the front-side inclined surface 23 b of the engaging projection 23 of the button support piece 22 . The front-side inclined surface 23 b therefore moves smoothly and the end of the upper surface part 33 a is flexed so as to move in the direction of the arrow CW in FIG. 7( c ). An end portion coming from the engaging hole 34 of the upper surface part 33 a then rides up onto the horizontal part 23 a of the engaging projection 23 (refer to FIG. 7( c )).
[0069] When the eject button 15 is moved further in the direction of the arrow R, the engaging projection 23 provided at the button support piece 22 of the slider 16 engages completely with the engaging hole 34 of the eject button 15 (refer to FIG. 7( d ), FIG. 8( d )) so that the eject button 15 is fitted to the slider 16 .
[0070] When removing the eject button 15 from the slider 16 , when a fairly strong force is applied in order to move the eject button 15 towards the front, i.e. in the direction of the arrow F in FIG. 7( e ), an end side edge 34 a of the engaging hole 34 slides smoothly over the rear-side inclined surface 23 c of the engaging projection 23 . The end of the upper surface part 33 a of the coupling part 33 of the eject button 15 is therefore subjected to force so as to move in the direction of arrow CW in FIG. 7( e ) so as to flex (refer to FIG. 7( e )).
[0071] Engagement of the engaging hole 34 with the engaging projection 23 is therefore released as a result of the flexing of the end of the upper surface part 33 a in the direction of the arrow CW in FIG. 7( e ). The eject button 15 can therefore move in the direction of the arrow F and can be removed from the slider 16 as a result.
[0072] The eject button 15 can therefore be detached from the slider 16 in a straightforward manner simply by moving the eject button 15 in a prescribed direction. This does not require any special tools or the use of parts other than the eject button 15 and the slider 16 .
[0073] A change can therefore easily be made to a desired eject button 15 by preparing various types of eject buttons 15 that match with the body 2 and the front panel 3 .
[0074] Next, a brief description is given with reference to FIG. 9 to FIG. 11 of installation and ejection of the cartridge 14 .
[0075] As shown in FIG. 1, when the cartridge 14 is lined up with the insertion/removal opening 4 of the flexible disc drive apparatus 1 and is inserted into the insertion/removal opening 4 , the cover 5 covering the insertion/removal opening 4 is pushed to the rear by the end of the cartridge 14 . This causes the cover 5 to move to the rear against the resistance of urging force of the torsion coil spring 9 , i.e. the cover 5 turns in the direction of arrow A in FIG. 9, and the insertion/removal opening 4 is opened. The cartridge 14 is then inserted to within the cartridge holder 28 , i.e. into a space surrounded by the top plate 29 , side plates 30 , 30 , and buttresses 31 , 31 (refer to FIG. 9). When the cartridge 14 is not installed, the slider 16 is positioned at the rear end of its range of movement, and the guide pins 30 b , 30 b , . . . of the cartridge holder 28 are positioned at the horizontal parts 19 a , 19 a , . . . of the slits 19 , 19 , . . . of the slider 16 . The cartridge holder 28 is therefore positioned at the upper end of its range of movement and is positioned at the same height as the insertion/removal opening 4 . The slider 16 is locked by lock means (not shown) at the rear end of the range of movement of the slider 16 .
[0076] As the cartridge 14 moves towards the end of the cartridge holder 28 , a shutter 14 b of the cartridge 14 moves in an opening direction, i.e. in the direction of arrow B in FIG. 1, so as to open upper and lower head access windows 14 c , 14 c (only the upper head access window 14 c is shown in FIG. 1). As a result of this, a magnetic head (not shown) constituting signal reading means and signal writing means can come into contact with or come close to the flexible disc 14 a and can read and write signals to and from the flexible disc 14 a.
[0077] When the cartridge 14 is then inserted as far as the back of the cartridge holder 28 (refer to FIG. 10), the lock at the rear end of the range of movement of the slider 16 is released. The slider 16 then immediately moves in the direction of arrow F in FIG. 10 to the front end of the range of movement due to the urging force of the tensioning coil spring 27 (refer to FIG. 11). While the slider 16 is moving from the rear end of the range of movement to the front end, the guide pins 30 b , 30 b . . . of the cartridge holder 28 move from the upper ends of the inclined parts 19 b , 19 b , . . . of the slits 19 , 19 , . . . of the slider 16 to the lower ends. The cartridge holder 28 therefore moves to the lower end of its range of movement and the flexible disc 14 a within the cartridge 14 supported at the cartridge holder 28 is installed in a disc rotating mechanism (not shown) and rotated by the disc rotating mechanism. As a result of movement of the slider 16 to the front end of the range of movement, the extent to which the eject button 15 fitted to the slider 16 projects outwards from the front panel 3 becomes large (compare the situations in FIG. 9 and FIG. 11). When the cartridge 14 is inserted to as far as the back of the cartridge holder 28 , ejection force at an eject mechanism (not shown) for ejecting the cartridge 14 to the front from the cartridge holder 28 is stored up. At this time, the lower end of the cover 5 forcibly makes contact with the upper surface of the cartridge 14 .
[0078] As a result of performing the above, installation of the cartridge 14 to the flexible disc drive apparatus 1 , i.e. loading of the flexible disc 14 a constituting a recording media is complete, and a state is attained where writing and reading of signals to and from the flexible disc 14 a is possible.
[0079] When reading and/or writing of signals to and from the flexible disc 14 a is complete and the cartridge 14 is to be extracted, the eject button 15 projecting from the front of the front panel 3 is pushed in, i.e. made to move in a direction shown by arrow C in FIG. 11.
[0080] The slider 16 moves to the rear as a result of pushing in the eject button 15 , i.e. moves in the direction of arrow R in FIG. 11. As the slider 16 moves towards the rear, the positions where the guide pins 30 b , 30 b , . . . of the cartridge holder 28 engage with the slits 19 , 19 , . . . of the slider 16 move from the lower ends of the inclined parts 19 b , 19 b , . . . to the upper ends so as to move the cartridge holder 28 upwards.
[0081] When the eject button 15 is pushed in until the slider 16 reaches the rear end of the range of movement, the slider 16 is locked at the rear end of the range of movement, the cartridge holder 28 reaches the upper end of the range of movement, and force stored up by the eject mechanism (not shown) is released. As a result, the cartridge 14 is moved from the cartridge holder 28 in the direction of ejection and part of the cartridge 14 projects outwards from the insertion/removal opening 4 of the front panel 3 . When the cartridge 14 moves in the ejection direction, the shutter 14 b is made to return to a closed position, i.e. is made to return to the state shown in FIG. 1.
[0082] The cartridge 14 can then be removed from the flexible disc drive apparatus 1 by grasping and pulling out the portion of the cartridge 14 projecting from the insertion/removal opening 4 . When the cartridge 14 is removed from the flexible disc drive apparatus 1 , the cover 5 turns in a direction shown by arrow D in FIG. 9 due to urging force of the torsion coil spring 9 so as to close the insertion/removal opening 4 .
[0083] With the above flexible disc drive apparatus 1 , engaging projections 12 , 12 , . . . are provided at the front panel 3 in order to fit the front panel 3 to the body 2 . The font panel 3 is then fitted to the body 2 as a result of the engaging projections 12 , 12 , . . . engaging with engaging holes 13 , 13 , . . . provided at the body 2 . However, the same results can also be demonstrated if engaging holes are formed in the front panel 3 and engaging projections are formed at the body 2 . In the modified example shown in FIG. 12, engaging projections 36 , 36 , . . . are formed at side walls 2 a of the body 2 and engaging holes 37 , 37 , . . . are formed at engaging pieces 11 , 11 , . . . of the front panel 3 .
[0084] In this modified example, when the front panel 3 moves in the direction of the arrow R, the engaging piece 11 slides smoothly over the inner surface of the side wall 2 a of the body 2 . The end of the engaging piece 11 then comes into contact with a front end-side inclined surface 36 a of engaging projection 36 and slides smoothly over. The engaging piece 11 then flexes in the direction of arrow CCW (refer to the single-dotted-and-dashed line of FIG. 12) and engaging hole 37 soon engages with engaging projection 36 .
[0085] When force is applied to move the front panel 3 in the direction of arrow F when the front panel 3 is removed from the body 2 , an end side edge 37 a of engaging hole 37 slides smoothly along a rear end-side inclined surface 36 b of the engaging projection 36 . The engaging piece 11 is therefore flexed in the direction of arrow CCW and this releases engagement of the engaging hole 37 and engaging projection 36 so that the front panel 3 can be moved in the direction of arrow F. It is then possible to remove the front panel 3 from the body 2 .
[0086] It is therefore possible in this modified example to attach and detach the front panel 3 to and from the body 2 without requiring any tools and without requiring any parts other than the front panel 3 and the body 2 .
[0087] Further, an engaging projection 23 is formed at the slider 16 and an engaging hole 34 is formed at the eject button 15 in order to fit the eject button 15 to the slider 16 at the flexible disc drive apparatus 1 but it is also possible to form an engaging hole at the slider 16 and form an engaging projection at the eject button 15 .
[0088] [0088]FIG. 13 shows a modified example configured in this manner, where an engaging hole 38 is formed in the button support piece 22 of the slider 16 and an engaging projection 39 is formed in the coupling part 33 of the eject button 15 . The engaging projection 39 is formed as a trapezoidal shape when viewed from the side and is comprised of a horizontal part 39 a , a top-side inclined surface 39 b , and abase-side inclined surface 39 c.
[0089] When the eject button 15 is lined up with the button support piece of the slider 16 and is moved in the direction of the arrow R, the top-side inclined surface 39 b of the engaging projection 39 comes into contact with the front end of the main piece 22 a of the button support piece 22 and slides smoothly over the end. The upper surface part 33 a of the coupling part 33 of the eject button 15 is then flexed in the direction of arrow CW and the engaging projection 39 slides smoothly over the upper surface of the main piece 22 a (refer to the single-dotted-and-dashed line of FIG. 13).
[0090] When the engaging projection 39 comes as far as the engaging hole 38 , the engaging projection 39 and the engaging hole 38 engage with each other so that the eject button 15 is supported at the slider 16 (refer to the double-dotted-and-dashed line of FIG. 13).
[0091] When the eject button 15 is removed from the slider 16 , the eject button 15 is held and force is applied in the direction of the arrow F. The base-side inclined surface 39 c of the engaging projection 39 therefore slides smoothly over the front side edge 38 a of the engaging hole 38 . The upper surface part 33 a of the coupling part 33 of the eject button 15 then flexes in the direction of arrow CW, the engagement of the engaging projection 39 and the engaging hole 38 is released, and the eject button 15 can be moved in the direction of arrow F. As a result of this, the eject button 15 can be removed from the slider 16 .
[0092] It is also straightforward to attach and detach the eject button 15 and the slider 16 in this modified example without requiring any tools and without requiring any parts other than the eject button 15 and the slider 16 .
[0093] The form and structure of each of the parts shown in the above embodiment and modified examples are given merely as examples for embodying the present invention and should by no means be interpreted as limiting the technological scope of the present invention. | There is therefore a need to be able to change a front panel in a straightforward manner without requiring tools or spare parts. In order to fulfill this need, a recording medium drive device of the present invention includes a body; at least signal reading means, of signal writing means for writing signals to a recording medium and the signal reading means for reading signals provided within the body, and a front panel covering the front of the body and having an insertion/removal opening for inserting and removing the recording medium to and from the body. The front panel is supported in a freely detachable manner as a result of engagement with the body, and the engagement is achieved by moving the front panel towards the body, and a force to move the front panel away from the body acts in a direction releasing the engagement. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to the field of fiber optic cables, in particular the present invention is directed to a method and apparatus for applying water barrier gels to optical fibers or fiber bundles at high speeds.
[0003] 2. Discussion of Related Art
[0004] Optical fibers are very small diameter glass strands which are capable of transmitting an optical signal over great distances, at high speeds, and with extremely low signal loss as compared to standard wire or cable networks. Optical fiber has found increasingly widespread application and currently constitutes the backbone of the worldwide telecommunication network. Because of this development, there has been a growing need for better quality optical fibers with a decrease in production time and costs, while ensuring adequate material strength for continued operation in increasingly harsh conditions. An important aspect for making better optical fibers is the reduction of structural faults or impurities in the protective coatings applied to the optical fiber during manufacture.
[0005] In general, optical fibers are manufactured from relatively large diameter glass preforms. Fiber optic preforms are generally made with three concentric glass layers. The inner layer, or core, is made of a very high quality, high purity SiO 2 glass, which for example, may be about 5 mm in diameter. This high purity core is the portion of the optical fiber in which the optical data is transmitted. Concentrically positioned around the high purity core is a second layer of glass, or cladding, with a lower index of refraction then the inner core, and generally is less pure. The difference in refraction indices between the core and cladding allows the optical signals in the core to be continuously reflected back into the core as they travel along the fiber. The combination of the core and cladding layers is often referred to as the “primary preform.” The optical fiber is then formed by heating and softening a portion of the preform, and rapidly drawing the softened portion with specialized equipment. The length of the drawn optical fiber is typically several thousands of times the length of the primary preform. Optical fibers intended for manufacture of telecommunications cables are typically coated with one or more polymer layers. The polymers provide mechanical protection of the fiber surface, and are colored for identification purposes. The coated optical fibers, singly or in groups, are typically covered with one or more of a number of jackets that provide structural support and environmental protections. The aggregate of the optical fiber, jackets, and additional integrated mechanical supports, is typically referred to as an optical fiber cable.
[0006] Exposure to water or humid air causes chemical changes in the surface of the optical fiber, resulting in a degradation of its ability to carry information. The most common method used to prevent or mitigate this degradation, is to reduce or eliminate water contact on the fiber surface by substantially filling the protective housings with a water barrier compound such as a hydrophobic fluid. For a number of reasons, including cable behavior during installation and long-term stability of the cables during use, the hydrophobic fluid is typically a gel. Gels tend to flow when mechanically stressed, but tend to remain static when under a low mechanical load.
[0007] Known methods for applying gel to fibers include drawing the fibers through a reservoir filled with gel so that the fibers are coated. However, the use of such a method often results in an inconsistent coating on the fibers due to air entrapped air. Accordingly, gel applicators have been developed, such as the device disclosed in Griser et al. U.S. Pat. No. 5,395,557, which attempts to reduce air entrapment by using a reservoir filled with pressurized gel. This device includes a housing having a cavity through which a plurality of separated optical fibers are fed. Gel is provided to the cavity from a gel reservoir via a pump. The optical fibers are then drawn through the gel so that the fibers are coated with the gel. The gel is provided under pressure in an attempt to reduce air gaps that may form upon the fibers. However, this technique has numerous draw backs. For example, a relatively large driving pressure is placed upon the gel in the reservoir to reduce air entrainment. Rapid application of barrier gel with this method requires relatively long and narrow application regions to prevent uncontrolled ejection of fluid from application regions, due to the large pressures.
[0008] Consequently, an apparatus for applying gel to a plurality of optical fibers, which substantially overcomes the above-recited drawbacks is highly desirable and needed in the optical fiber industry.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to eliminating the above problems associated with the application of water barrier fluids, such as a gel, to optical fibers and optical fiber bundles. Thus, the invention improves the quality of the optical fiber cable and manufacturing process used to apply the gel.
[0010] The present invention addresses the above problems by providing a gel application apparatus that applies the gel with a flow having a high velocity in a direction normal to the surface of the optical fibers, as the fibers pass between an entrance die and an exit die. This creates a linear velocity great enough to overcome the kinetic energy of an air boundary layer traveling along with the fibers through the die entrance. Thus, the method and apparatus is capable of accurately and efficiently coating optical fibers while eliminating unwanted air pockets.
[0011] More specifically, the present invention relates to an apparatus for applying a coating of a water barrier fluid, such as a gel to an optical fiber including a die having an entrance side and exit side. An orifice is formed in the die which extends through the entrance side and exit side in a width-wise direction, and which is dimensioned to allow for an optical fiber to be drawn therethough. A cavity is formed in the die, and is in fluid communication with the orifice. A fluid insertion opening is formed in the die for injecting fluid into the cavity. When a fluid is injected into the cavity it travels through the cavity and out of a circumferential exit gap, such that it coats a portion of the optical fiber. The circumferential gap is formed at a meeting point between an inner portion of the cavity and the respective orifices of the entrance and the exit die.
[0012] The present invention still further provides for an apparatus for applying a coating to several optical fibers or a bundle of optical fibers, including an entrance die having an orifice which is dimensioned to allow for a bundle of optical fibers to be drawn therethrough. Also, an exit die having an orifice is provided. The entrance die and the exit die, respectively, have inner sides, which define a cavity. The cavity is in fluid communication with the orifice of the entrance die and the orifice of the exit die, such that a circumferential gap is formed at a meeting point between the cavity and the respective orifices of the entrance die and the exit die. Thus, the circumferential gap is radially surrounded by an extension of the cavity, to define a critical flow region. A plurality of baffles are formed in the exit die, which are operative to inject fluid into the cavity. Also provided is a main body, which supports the entrance die and the exit die. The main body includes a passageway which is in fluid communication with the plurality of baffles. A retaining ring is also included, which secures the entrance die and the exit die to the main body.
[0013] Additionally, when fluid is passed through the circumferential gap toward the plurality of fibers it travels at a velocity which is sufficient to overcome kinetic energy of an air boundary layer traveling along with the optical fibers drawn through the entrance die, prior to the fibers being drawn through the exit die.
[0014] Still further the invention provides for a method of applying a water barrier fluid, such as a gel to one or more optical fibers, including the steps of drawing an optical fiber through an orifice formed in a die; and injecting a fluid into a cavity formed in the die, wherein the cavity is in fluid communication with the orifice, and wherein the fluid is pressurized out of the orifice and onto the optical fiber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The advantages, nature and various additional features of the invention will appear more fully upon consideration of illustrative embodiments of the invention which are schematically set forth in the drawings, in which:
[0016] FIG. 1 is front view of an exemplary arrangement of fibers having a gel provided thereon, according to the present invention;
[0017] FIG. 2 is an exploded perspective view of an applicator according to the present invention;
[0018] FIG. 3 is a sectional view of an applicator according to the present invention being supported by a base; and
[0019] FIG. 4 is an enlarged sectional view of a critical flow region of the applicator.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0020] The present invention will be explained in further detail by making reference to the accompanying drawings, which do not limit the scope of the invention in any way.
[0021] With reference to FIG. 1 , a plurality of optical fibers 10 are shown in a radial arrangement forming a fiber bundle 22 . In this embodiment, twelve optical fibers 10 are shown; however, it will be appreciated that the optical fiber bundle 22 may consist of a varying arrangement and number of optical fibers 10 . The fiber bundle 22 is shown as having an outer portion 24 and an inner portion 26 .
[0022] According to the present invention, a water barrier fluid 28 , for example, a thixotropic gel, is disposed onto the outer 24 and inner 26 portions of the fiber bundle 22 , as described below. The gel 28 acts to prevent ingress of water to the optical fiber surface produced from direct liquid contact or exposure to humid air. Although, thixotropic gel is described, any of a broad classification of fluid polymeric materials may be used, provided that the materials meet the criteria of chemical compatibility with the optical fibers and their coatings, and that the water barrier fluid possess a chemical nature that materially limits the transport of water to the optical fiber surface. For example, other suitable materials may include Newtonian liquids, dilute solutions containing polymer molecules, and liquid slurries containing solid particles, although not limited to such materials. In addition, it is typically desired that the fluid does not leak from open ends of cable housings. This undesirable behavior would result in an eventual exposure of a length of each fiber being exposed to the cable environment. The intrinsic mechanical behavior of gels makes this class of materials most appropriate for use as a water barrier in optical fiber cables.
[0023] FIG. 2 and FIG. 3 illustrate a die assembly 30 for forming the above cable. The die assembly 30 includes a retaining ring 32 which is attached to a main body die 72 . Positioned between the retaining ring 32 and the main body die 72 , is an entrance die 42 and an exit die 54 . These elements are operative to allow for optical fibers to pass through a center thereof.
[0024] In further detail, the retaining ring 32 has an entrance side 34 and a containing side 36 , which are in communication with each other. The containing side 36 has a recessed area for accommodating the entrance die 42 . The retaining ring 32 also has an outer portion 40 , which is threaded.
[0025] The entrance die 42 has an inner side 44 , and an outer side 46 . The entrance die 42 may be made from a material, such as tungsten carbide. The inner side 44 has a conical center portion 48 and is dimensioned so as to allow the entrance die 42 to be disposed within the recessed area 38 of the retaining ring 32 so that the outer side 46 of the entrance die 42 is in contact with a wall portion of the recessed area 38 . An orifice 50 is provided in the entrance die 42 and is centrally positioned in relation to the conical center portion 48 . The outer side 46 of the entrance die 42 has an inwardly tapered section which is angled towards the orifice 50 .
[0026] In further accordance with the present invention, the exit die 54 is provided with an inner side 56 and an outer side 58 . The exit die 54 may be made from a material, such as carbon steel. The exit die 54 also has a centrally positioned orifice 60 , which is concentrically positioned with respect to the orifice 50 of the entrance die 42 . The exit die 54 further contains a plurality of baffles or baffle holes 62 , which are disposed around the orifice 60 .
[0027] A cylindrically shaped spacer ring 64 is positioned between the entrance die 42 and the exit die 54 . The spacer ring 64 is operative to position the entrance die 42 and the exit die 54 at predetermined relationship with respect to each other. The spacer ring 64 is dimensioned to contact wall portions of the entrance and exit dies 42 and 54 , so as not to interfere with the plurality of baffles 62 and orifice 60 of the exit die 54 , and orifice 50 of the entrance die 42 .
[0028] The contiguous positioning of the entrance and exit dies 42 and 54 form a fluid cavity 66 , as shown in FIGS. 3 and 4 . The fluid cavity 66 is defined by the conical center portion 48 of the entrance die 42 and the inner side 56 of the exit die 54 . The fluid cavity 66 extends circumferentially around, and is in communication with, the orifice 50 of the entrance die 42 and the orifice 60 of the exit die 54 , thus producing an exit gap G, having a dimension d 1 .
[0029] With further reference to FIG. 4 , the exit gap G forms an integral part of a critical flow region 69 . The critical flow region 69 is further defined by dimensions d 2 and d 3 , which respectively represent the orifice diameters of the entrance die 42 and the exit die 54 . To prevent sporadic application of a barrier coating to the fibers passing through the invention, the barrier fluid must not be materially disturbed by air that is naturally accelerated toward the die by the approaching fibers. The present invention sizes the critical flow region such that the kinetic energy of the barrier fluid that passes through the exit gap G and contacts the fibers is large in comparison to the air accelerated toward the die entrance by the moving fibers. The upper limit for the dimensions of the critical flow region is chosen such that the kinetic energy of the barrier fluid is larger, for example on the order of several hundred times that, of the potentially entrained air. The lower limit for the dimensions of the critical flow region is constrained by the need to apply the barrier fluid at pressures readily supplied by inexpensive process fluid handling equipment. Also taken into consideration when determining the dimensions of the critical flow region is the desired fiber bundle geometry, as required by the cable product. An exemplary embodiment of gap dimensions which have been shown to produce favorable results include an entrance die diameter d 2 and an exit die diameter d 3 of 1.04 mm, and a gap G width d 1 of 0.5 mm. During testing, such dimensions have resulted in a kinetic power of an extrudate of 4.94 Watts. It was also found that a boundary layer of air around a bundle of 12 fibers traveling at a rate of 1000 m/min produced 0.01 Watts of power. Thus, the kinetic power of the extrudate is much larger than the boundary layer of air around the bundle, which results in a proper application of gel to the bundle without the presence of detrimental air pockets. These dimensions are given by way of example and may change depending on the size of the bundle to be coated.
[0030] A slip ring 70 is provided around an outer circumferential surface of both the entrance 42 and exit 54 die. The slip ring 70 forms a slip fit with the dies and is operative to aid in keeping the dies properly aligned.
[0031] The main die body 72 has a first recessed portion 74 , for receiving the exit die 54 , the spacer ring 64 and the entrance die 42 . The recessed portion 74 has a first diameter which is dimensioned to form a proper fit with the slip ring 70 . The main die body 72 also has a second recessed portion 75 with threads formed thereon, for engaging with the outer threaded portion 40 of the retaining ring 32 . Accordingly, when the retaining ring 32 is threadedly engaged with the main die body 72 , the entrance die 42 , the spacer ring 64 , the exit die 54 and the slip ring 70 are secured together to form the die assembly 30 .
[0032] The main die body 72 also has a conical side 78 which is angled in towards a center portion of the die main body 72 . It is also noted that the conical design is given by way of example, and that this side may be formed to be flat in shape. An orifice 80 is provided in the main die body 72 which is centrally positioned with respect to the conical side 78 , so as to be in communication with the orifice 60 of the exit die 54 and the orifice 50 of the entrance die 42 . In one embodiment of the present invention, an o-ring 82 , as shown in FIG. 3 , is provided between the retaining ring 32 and the entrance die 42 . Additionally, an o-ring 84 is provided between the exit die 54 and the die main body 72 . The o-rings may be made from a material, such as nitrile rubber.
[0033] An injection port 86 is provided on an outer portion of the main body 72 . A cavity 87 , which may be annular, is formed to be in communication with the injection port 86 , and abuts baffle holes 62 . It will also be appreciated that the injection port 86 may be placed in the conical side 78 of the main body 72 . The injection port 86 is formed to be in communication with the baffles 62 of the exit die 54 . The injection port 86 is also connected to a pumping system, which is operative to supply the gel in a pressurized state and is capable of providing a sufficient quantity of fluid at uniform rates to produce the desired amount to be combined with the group of optical fibers, which is passed therethrough.
[0034] With further reference to FIG. 3 , during an implementation of the applicator for high-speed gel buffering of optical fiber bundles according to the present invention, the bundle of optical fibers 22 are fed into the die assembly 30 through the entrance side 34 of the retaining ring 32 and into the entrance die 42 . The bundle of fibers 22 is then drawn through to the exit die 54 , while passing the critical flow region 69 . The bundle 22 is then drawn through the outer side 58 of the exit die 54 , and out of the die assembly 30 . It is noted that the present invention can also be implemented to coat an individual optical fiber, as well as the described optical fiber bundle 22 .
[0035] The coating of the optical fiber bundle 22 is accomplished by pressurizing gel into the injection port 86 of the main body 72 and through the cavity 87 . The pressurized gel then travels into the fluid cavity 66 , which is formed between the entrance and exit dies 42 and 54 . The shape of the fluid cavity 66 is chosen to have a section wide enough such that resistance to filling of the cavity is small, and varies smoothly, such that flow-induced shear stress on the gel is gradually increased toward the exit gap G.
[0036] With additional reference to FIG. 4 , the pressurized gel is ejected into the critical flow 69 region via the exit gap G and onto the bundle of fibers 22 . The orifice 50 of the entrance die 42 has a dimension d 2 so as to slightly compress the original diameter of the bundle of fibers 22 . As discussed above, an exemplary size of d 2 is 1.04 mm and is chosen to compact the individual optical fibers 10 of the bundle 22 , towards each other such that excess air is removed from the bundle 22 and the fiber group attains the degree of compaction required by the cable manufacturing process. With additional reference to FIG. 1 , upon the pressurizing of the gel 28 onto the bundle 22 , the gel 28 not only coats the outer portion of the bundle 24 , but is also forced into the inner portion 26 of the bundle 22 .
[0037] According to the present invention, the gel 28 is applied by controlling the volumetric flow rate and pressure. For example, for a flow rate of about 57,000 mm 3 per minute of gel, cavity pressure of 48,000 Pascal was measured while applying gel on a bundle of 12 fibers. The gel 28 is applied at a high flow rate or velocity in a direction normal to the surface of the optical fibers as the fibers pass between the entrance die 42 and an exit die 54 . For example, a mean gel velocity, normal to the fiber bundle in the gap, of 13,000 mm per minute may be used. This creates a linear velocity great enough to overcome the kinetic energy of an air boundary layer traveling along with the fibers toward the die entrance. This is because the kinetic power of the extruded gel is much larger than the boundary layer of air around the bundle of fibers 22 . Thus, the method and apparatus is capable of accurately and efficiently combing fluids with optical fibers while eliminating unwanted air pockets.
[0038] It will be appreciated by one skilled in the art that the proper application of the gel, according to the present invention, is dependent upon the proper dimensioning of the elements of the die assembly 30 . For example, such critical dimensions include the respective diameters d 2 and d 3 and concentricity of the orifices 50 and 60 , of the entrance die 42 and the exit die 54 , and the width d 1 of the exit gap G, as discussed above.
[0039] Although the invention describes the use of a plurality of baffles in the exit die, and an injection port in the main die body, it will be appreciated that a plurality of injection ports may be used, and that the size and shape of the baffles and the injection port may be altered depending on the type of gel used, the shape of the cavity and the rate at which the fibers are drawn through the die assembly.
[0040] Although the invention describes the use of a conical region formed on the entrance die for creating a particular shaped cavity, it will be appreciated that various configurations of the inner side of the entrance die, and the inner side of the exit die may be used to obtain various shaped cavities depending on the desired flow behavior of the gel.
[0041] It is, of course, understood that departures can be made from the preferred embodiments of the invention by those of ordinary skill in the art without departing from the spirit and scope of the invention that is limited only by the following claims. | A method for combining a water barrier fluid to a bundle of optical fibers including an entrance die having an orifice which is dimensioned to allow for a bundle of optical fibers to be drawn therethrough. Also, an exit die having an orifice is provided. The entrance die and the exit die, respectively, have inner sides which define a cavity. The cavity is in fluid communication with the orifice of the entrance die and the orifice of the exit die, such that a gap is formed at a meeting point between the cavity and the respective orifices of the entrance and the exit die. The gap is radially surrounded by an extension of the cavity to define a critical flow region. A plurality of baffles are formed in the exit die which are operative to inject fluid into the cavity. Also provided is a main body which supports the entrance die and the exit die. The main body includes a passageway that is in fluid communication with the plurality of baffles. A retaining ring is included which secures the entrance die and the exit die to the main body. | 2 |
TECHNICAL FIELD
[0001] This invention relates to computer networks, and more particularly, to an improved user interface preferably for use in connection with a personal computer (e.g., local terminal) or the like while connected to a remote computer.
BACKGROUND OF THE INVENTION
[0002] Remote terminals have been in widespread use for many years. Recently, with the move towards distributed computing, it has been more and more common to utilize a host computer, often a large mainframe computer, from a local terminal by accessing the host computer over a data network. The terminal, in many cases, is actually a personal computer (“PC”) which is programmed in such a manner as to communicate with the host computer. Often, the PC is programmed to emulate a terminal so that the host computer cannot distinguish it from a simple “dumb” terminal.
[0003] One issue to be addressed by a designer of such systems is the relatively high data processing rates required to update the screen information downloaded from the host computer. In prior art systems, the programming to emulate a “dumb” terminal (the “terminal emulator”) accomplished such updates by comparing the old screen with the new screen downloaded from the host computer.
[0004] The terminal emulator would then “repaint” the PC display, using defined display parameters. Most prior art systems use an industry termed “text-to-graphics conversion”, in which screens of textual data downloaded from the host computer are reformatted into information suitable for display as part of a graphical user interface (“GUI”). The GUI is much more user friendly and provides additional functionality as compared to screens of textual data. In addition, the GUI may be customized as the user desires.
[0005] However, the above described comparison of the old screen with the new screen still requires significant bandwidth. Remote terminals that require character-based screen updating, for example, require information to be transmitted to the host computer upon each and every data entry by the user. Therefore, each data entry requires the transmission of such data, transmission from the host of the newly changed screen of information, comparison of the old and new screen information by the terminal emulator, and the repainting of the PC display.
[0006] For example, if the user were entering a name in a “name” field, the above updating steps must occur for each character in the name that is entered. Such frequent updating consumes significant processing power.
[0007] Another drawback of prior art systems is the high processing speeds required in using a mouse, a standard pointing device, in connection with a terminal emulator having a GUI display. The mouse inputs signals to move the cursor position among various fields in the display. Each time that the user clicks the mouse to cause a move on the screen, the terminal emulator program calculates the combination of keystrokes required to simulate such a move. The program then transmits each of those keystrokes to the host computer and downloads new screens of information in order to accomplish the movement on the screen. However, these calculations, transmissions, simulations, and displays again require significant processing power to accomplish. It is desirable to minimize the bandwidth required by the use of a pointing device in a terminal emulator program.
[0008] In view of the above, it can be appreciated that there exists a need in the prior art for better techniques in terminal emulation to save on processing bandwidth requirements, while maintaining or improving on its advantages and user-friendly features.
SUMMARY OF THE INVENTION
[0009] The above and other problems of the prior art are overcome in accordance with the present invention which relates to a terminal emulator that more efficiently accomplishes screen updates, as well as more efficiently accomplishing cursor movement with a pointing device, such as a mouse.
[0010] In accordance with the invention, the emulator divides the screens transmitted from the host computer into a plurality of objects, and monitors which objects have been affected by a newly input character. When the PC receives an updated screen, the emulator program compares only the object or objects affected by the newly input character, rather than comparing the entire screen. Then, the emulator repaints only the changed portion, or object, on the PC display. This improvement saves on bandwidth, since only portions of the painted screen, rather than the entire screen, need to be compared and regenerated.
[0011] Another technical advance achieved in accordance with the present invention relates to a method of using a pointing device, in connection with a terminal emulator, that requires less processing power. Depending on where the user clicks the mouse, the emulator calculates the most efficient combination of keyboard strokes required to simulate the cursor movement. The emulator then transmits the keystroke information to the remote computer and receives updated screen information back, thereby enabling it to display the appropriate cursor movement to the user.
[0012] The terminal emulator may calculate a keystroke combination that minimizes the required number of keystrokes to move the cursor from one point to another on the display. It may, for example, use a maximum number of “tab” steps, and then a few “backspace” steps, in order to simulate the cursor movement. This minimizing of keystrokes cuts down the required date processing rate, since fewer transmissions of keystroke and screen information are required.
[0013] In summary, by dividing the screens into various objects and comparing and repainting only the changed objects in the display, and by programming the emulator to calculate the most efficient steps to move the cursor, data processing rate requirements are reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a fuller understanding of the invention, reference is made to the following description taken in connection with the accompanying drawings, in which:
[0015] [0015]FIG. 1 is a depiction of a small portion of an exemplary computer network;
[0016] [0016]FIG. 2 shows a flow chart of the steps to be implemented by a local terminal, in order to practice an exemplary screen updating embodiment of the subject invention;
[0017] [0017]FIG. 3 shows an exemplary screen layout;
[0018] [0018]FIG. 4 shows an exemplary screen layout divided into the object elements of the subject invention;
[0019] [0019]FIG. 5 depicts a pointing device cursor movement, more fully described later herein; and
[0020] [0020]FIG. 6 shows a flow chart of the steps to be implemented by a local terminal, in order to practice the cursor movements of the subject invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] [0021]FIG. 1 shows a local area network 101 with a plurality of computers 102 through 105 connected thereto. The network 101 may be, for example, an Ethernet, or any other suitable local or wide area network.
[0022] Computer 102 is designated as a remote host which runs applications software that is accessible from any of local terminals 103 to 105 , which may be implemented as PCs programmed to emulate “dumb” terminals.
[0023] U.S. Pat. Nos. 5,792,659 and 5,812,127, assigned to the same assignee as the present patent application, disclosed various techniques for recognizing the particular screen downloaded at the PC, utilizing a screen identification (“ID”) code. As the screens are recognized, they may be displayed to the user in various formats and with various defined attributes.
[0024] [0024]FIG. 2 shows a flow chart of the novel method of the present invention, which can be implemented in any of a variety of programming languages to update the screens at the local terminal.
[0025] Specifically, as the program enters start 201 , a screen of information is transmitted from the host computer to the local terminal at operational block 202 . The program recognizes, at decision block 203 , the screen (i.e., it recognizes whether the screen has a different layout or different fields, etc. from the previous screen) by using identification methods, such as those described in the commonly owned '659 or '127 patents referenced above. If it is a new image having a new screen ID, the program divides the screen into objects at operational block 204 .
[0026] It is noted that the division of the screens into objects may be based on the input fields, as described in this embodiment, or on other division methods as would be obvious to those of ordinary skill in the art. For example, each object could comprise a character position, or blocks of characters. Alternatively, the entire screen could be divided into an appropriate grid, where each square in the grid comprises an object. Any number of screen division techniques known in the art could be used at block 204 , as long as they suitably minimize the screen area needed to be compared and regenerated.
[0027] Continuing with reference to FIG. 2, upon data entry by the user, the program monitors, at block 205 , which objects are affected by the new entry. It is understood that the invention is meant to cover various possible types of user input, such as characters or function keys.
[0028] The local computer then transmits the new data information to the host computer at block 206 . Returning in the flow chart to block 202 , the host computer processes the information and downloads updated screen information to the local computer. Upon receiving the updated screens at the local terminal, the terminal emulator program recognizes the screen at block 203 . It then compares only the changed objects, rather than the entire screen, in the new and old screens at operational block 207 . The program then repaints only the changed objects in the PC display at block 208 , thereby reducing the amount of processing power required to compare and repaint the screens.
[0029] [0029]FIG. 3 shows an example screen for a particular type of data record to be entered. The exemplary screen of FIG. 3 is entitled “Transaction Record” and includes 5 fields of data as shown. For example, fields 301 and 302 are indicated as “first name” and “last name”. The drawing of FIG. 3 is intended to represent the actual display of the screen after it is recognized by the local terminal emulator and displayed on the PC, as previously described therein.
[0030] [0030]FIG. 4 shows the same screen as shown in FIG. 3, with blocks 401 - 406 comprising the above described objects into which the screen is divided. Each object comprises a data field, which may change upon data input by the user. The program monitors which objects are affected by data input. It then only needs to compare and recreate those affected objects for display, rather than the entire screen.
[0031] [0031]FIG. 5 depicts an example of a cursor movement in connection with a GUI, utilizing another novel method of the present invention. The user uses a mouse to move the cursor from position 501 in one field to position 502 within another field.
[0032] [0032]FIG. 6 shows the steps required for the terminal emulator to accomplish such cursor movement, in accordance with the present invention. Specifically, as the program enters start 601 , upon receiving a cursor movement signal, the program calculates, at operational block 602 , the optimum keystrokes or keystroke combination to use, to cause the necessary movement on the screen. As an example, the program may calculate the combination that requires the minimum number of keyboard strokes, thereby minimizing the data processing and transmissions of information required.
[0033] In the screen layout of FIG. 5, the optimum keystrokes to move from points 501 to 502 includes 4 tab strokes to move from the first position in the “first name” field to the first position in the “acct no.” field. Assuming that the “address” field has a total length of 40 character positions, it would then require only 5 backspace strokes to reach point 502 in the “address” field. This keystroke combination results in a total number of 9 “steps” to move the cursor from point 501 to point 502 .
[0034] Conventional techniques for accomplishing this same movement might require 4 tab strokes to reach the first position in the “address” field. It may then use 34 forward space strokes to reach point 502 , resulting in a total of 38 steps. In the above described preferred embodiment, the program utilizes a maximum number of large “steps” (e.g., tabs) and a minimum number of small “steps” (e.g., backspaces). Conventional techniques do not encompass this concept of optimizing the steps to use.
[0035] Returning to FIG. 6, the program sends the first keystroke information to the host computer at block 603 , which then downloads updated screen information to the local PC at block 604 . If at decision block 605 there are remaining keystrokes to be executed, control is returned to block 603 , where the next keystroke information is sent to the host computer. Updated screen information is again received by the local terminal at bock 604 , and the loop continues until all of the calculated keystrokes have been executed.
[0036] Blocks 602 - 605 comprise a method to simulate keystrokes and is, of course, transparent to the user. If at block 605 it is determined that the final keystroke has been simulated, the desired screen has been received at the local computer. The terminal emulator then displays that screen at block 605 , showing the desired cursor movement to the user.
[0037] It is anticipated by the invention that various parameters for optimizing the simulated keystrokes may be defined. In other possible embodiments, various combinations of simulated keyboard movements and keycodes can be utilized in this technique. For example, the method may encompass combinations of control and escape keycodes.
[0038] While the above describes the preferred embodiments of the invention, it will be apparent to those of ordinary skill in the art that numerous modifications and/or additions may be implemented. Such modification and variations are intended to be covered by the following claims. | An enhanced user interface for a remote terminal is described. A terminal emulator program divides screens received at a local terminal into objects. The program monitors the objects affected by data inputs by the user. Upon receiving new screens of information from the host computer, the program compares and repaints only the affected objects, rather than the entire screen. In another technique, upon receiving signals from a pointing device to cause cursor movements, the program calculates the optimal keystrokes or combination of keystrokes required. It then simulates those keystrokes to accomplish the desired movement on the screen. Both techniques meet a demand for savings in processing bandwidth. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to U.S. Provisional Application No. 61/177,343, filed May 12, 2009.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of ultraviolet light stabilized polyester compositions, and more particularly it relates to ultraviolet light stabilized polyester compositions for manufacturing articles having good mechanical properties and a good surface appearance upon long-term outdoor exposure and/or heat exposure.
BACKGROUND OF THE INVENTION
[0003] As a result of their good heat resistance, mechanical strength, electrical properties, good processability and other properties, thermoplastic polyesters are used in a broad range of applications including automotive applications; recreation and sport parts; home appliances, electrical/electronic parts; power equipment; and buildings or mechanical devices. However, many of these applications are used outdoors and require that articles made from polyesters be exposed to weathering conditions during normal use. If used in outdoor applications, polyester compositions or articles made thereof can be subject to rapid and severe degradation/deterioration because of weathering conditions such as for example high temperature, humidity, exposure to ultraviolet (UV) and other kind of radiations. Such kind of exposures to ultraviolet radiation and high temperature sources impair the properties of the article during normal use. Upon prolonged weathering conditions, articles made of polyesters can degrade, thus leading to a loss of physical properties like tensile strength and a diminished aesthetic appearance, for example discoloration and/or surface cracking.
[0004] In an attempt to improve the protection of a polyester composition against the deteriorating effect of light and high temperature, it has been the conventional practice to add light stabilizers to polyester composition.
[0005] US patent application 2003/0109629 discloses a polyester composition comprising an impact modifier, a hindered amine light stabiliser (HALS) and an UV absorber, especially a hydroxyphenyl-triazine UV absorber. However, the disclosed composition exhibits reduced colour change (expressed by deltaE) only for an indoor weathering exposure of 810 hours, i.e. about 34 days.
[0006] JP 2000-191918 discloses a composition comprising from 98.10 to 99.94 wt-% of a polyester, a compound comprising a triazine, a benzotriazole-based ultraviolet absorber and a hindered amine light stabiliser. However, molded articles based on the disclosed polyester compositions may suffer from an unacceptable deterioration of their mechanical properties upon a long-term weathering exposure and upon a long-term high temperature exposure.
[0007] Unfortunately, with the existing technologies and the commercially available light stabilizers for polymers, molded articles based on polyester compositions suffer from an unacceptable deterioration of their mechanical properties and aesthetic appearance upon a long-term weathering exposure and upon a long-term high temperature exposure. For this reason, the existing technologies are insufficient for highly demanding applications.
[0008] Consequently, there is a need for an efficient protection of polyester compositions and articles thereof against deterioration due to a weathering exposure, in particular light-induced degradation, and heat-induce thermo-oxidation.
SUMMARY OF THE INVENTION
[0009] There is disclosed and claimed herein a polyester composition comprising a) at least one polyester resin; b) from at or about 0.3 to at or about 3 wt-% of at least three UV stabilizers; wherein one of the at least three UV stabilizers is b1), another one is b2) and another one is b3); and c) from at or about 1 to at or about 60 wt-% of one or more reinforcing agents, the weight percentage being based on the total weight of the polyester composition. Compositions according to the invention offer good stability against the deleterious effects of long-term weathering exposure (e.g. UV exposure) and good mechanical properties upon high temperature exposure.
DETAILED DESCRIPTION OF THE INVENTION
[0010] As used throughout the specification, the phrases “about” and “at or about” are intended to mean that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but may be approximate and/or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art. In general, an amount, size, formulation, parameter or other quantity or characteristic is “about” or “approximate” whether or not expressly stated to be such.
[0011] The polyester composition of the present invention comprises at least one polyester resin. Preferably, the at least one polyester resin is present in an amount from at or about 10 to at or about 80 wt-%, more preferably, in an amount from at or about 20 to at or about 70 wt-%, and still more preferably in an amount from at or about 30 to at or about 60 wt-%; the weight percentages being based on the total weight of the polyester composition.
[0012] The at least one polyester resin is preferably selected from thermoplastic polyesters derived from one or more dicarboxylic acids and one or more diols, copolyester thermoplastic elastomers (TPC) and mixtures thereof. Thermoplastic polyesters are typically derived from one or more dicarboxylic acids (where herein the term “dicarboxylic acid” also refers to dicarboxylic acid derivatives such as esters) and one or more diols. In preferred polyesters the dicarboxylic acids comprise one or more of terephthalic acid, isophthalic acid, and 2,6-naphthalene dicarboxylic acid, and the diol component comprises one or more of HO(CH 2 ) n OH (I); 1,4-cyclohexanedimethanol; HO(CH 2 CH 2 O) m CH 2 CH 2 OH (II); and HO(CH 2 CH 2 CH 2 CH 2 O) z CH 2 CH 2 CH 2 CH 2 OH (III), wherein n is an integer of 2 to 10, m on average is 1 to 4, and z is on average about 7 to about 40. Note that (II) and (III) may be a mixture of compounds in which m and z, respectively, may vary and that since m and z are averages, they do not have to be integers. Other dicarboxylic acids that may be used to form the thermoplastic polyester include sebacic and adipic acids. Hydroxycarboxylic acids such as hydroxybenzoic acid may be used as comonomers. Examples of thermoplastic polyesters that can be included in the polyester composition according to the present invention may be selected from the group consisting of poly(ethylene terephthalate) (PET), poly(trimethylene terephthalate) (PTT), poly(1,4-butylene terephthalate) (PBT), poly(ethylene 2,6-naphthoate) (PEN), and poly(1,4-cyclohexyldimethylene terephthalate) (PCT), poly(1,4-butylene terephthalate) (PBT) and copolymers and blends of the same, and more preferably the polyester is poly(ethylene terephthalate) (PET), poly(trimethylene terephthalate) (PTT), poly(1,4-butylene terephthalate) (PBT), poly(1,4-cyclohexyldimethylene terephthalate) (PCT), and copolymers and blends of the same.
[0013] Copolyester thermoplastic elastomers (TPC) such as copolyetheresters or copolyesteresters are copolymers that have a multiplicity of recurring long-chain ester units and short-chain ester units joined head-to-tail through ester linkages, said long-chain ester units being represented by formula (A):
[0000]
[0000] and said short-chain ester units being represented by formula (B):
[0000]
[0000] wherein
G is a divalent radical remaining after the removal of terminal hydroxyl groups from poly(alkylene oxide)glycols having preferably a number average molecular weight of between about 400 and about 6000; R is a divalent radical remaining after removal of carboxyl groups from a dicarboxylic acid having a molecular weight of less than about 300; and D is a divalent radical remaining after removal of hydroxyl groups from a diol having a molecular weight preferably less than about 250; and wherein said copolyetherester(s) preferably contain from about 15 to about 99 wt-% short-chain ester units and about 1 to about 85 wt-% long-chain ester units.
[0014] As used herein, the term “long-chain ester units” as applied to units in a polymer chain refers to the reaction product of a long-chain glycol with a dicarboxylic acid. Suitable long-chain glycols are poly(alkylene oxide) glycols having terminal (or as nearly terminal as possible) hydroxy groups and having a number average molecular weight of from about 400 to about 6000, and preferably from about 600 to about 3000. Preferred poly(alkylene oxide) glycols include poly(tetramethylene oxide) glycol, poly(trimethylene oxide) glycol, poly(propylene oxide) glycol, poly(ethylene oxide) glycol, copolymer glycols of these alkylene oxides, and block copolymers such as ethylene oxide-capped poly(propylene oxide) glycol. Mixtures of two or more of these glycols can be used.
[0015] The term “short-chain ester units” as applied to units in a polymer chain of the copolyetheresters refers to low molecular weight compounds or polymer chain units. They are made by reacting a low molecular weight diol or a mixture of diols with a dicarboxylic acid to form ester units represented by Formula (B) above. Included among the low molecular weight diols which react to form short-chain ester units suitable for use for preparing copolyetheresters are acyclic, alicyclic and aromatic dihydroxy compounds. Preferred compounds are diols with about 2-15 carbon atoms such as ethylene, propylene, isobutylene, tetramethylene, 1,4-pentamethylene, 2,2-dimethyltrimethylene, hexamethylene and decamethylene glycols, dihydroxycyclohexane, cyclohexane dimethanol, resorcinol, hydroquinone, 1,5-dihydroxynaphthalene, etc. Especially preferred diols are aliphatic diols containing 2-8 carbon atoms, and a more preferred diol is 1,4-butanediol.
[0016] Preferably, the polyester composition according to the present invention comprises one or more thermoplastic polyesters that are selected from poly(ethylene terephthalate) (PET), poly(trimethylene terephthalate) (PTT), poly(1,4-butylene terephthalate) (PBT), poly(ethylene 2,6-naphthoate) (PEN), poly(1,4-cyclohexyldimethylene terephthalate) (PCT), copolyester thermoplastic elastomers (TPC) and mixtures thereof. More preferably, the polyester composition according to the present invention comprises one or more thermoplastic polyesters that are selected from poly(ethylene terephthalate) (PET), poly(1,4-butylene terephthalate) (PBT) poly(1,4-cyclohexyldimethylene terephthalate) (PCT) and mixtures thereof.
[0017] The polyester composition according to the present invention comprises from at or about 0.3 to at or about 3 wt-% of at least three UV stabilizers, wherein one of the at least three UV stabilizers is b1), another one is b2) and another one is b3), the weight percentage being based on the total weight of the polyester composition.
[0018] Preferably, the at least three UV stabilizers are selected from the group consisting of b1) one or more benzotriazole derivatives, b2) one or more triazine derivatives and/or pyrimidine derivatives; and b3) one or more hindered amine derivatives (also known as hindered amine type light stabilizers (HALS)).
[0019] Preferably, the one or more benzotriazole derivatives b1) are present in an amount from at or about 0.01 to at or about 2.98 wt-%, the one or more triazine derivatives and/or pyrimidine derivatives b2) are present in an amount from at or about 0.01 to at or about 2.98 wt-%, and the one or more hindered amine derivatives b3) are present in an amount from 0.01 to at or about 2.98 wt-%, provided that the sum of b1)+b2)+b3) is between at or about 0.3 and at or about 3 wt-%, the weight percentage being based on the total weight of the polyester composition.
[0020] Preferably, one of the three UV stabilizers is one or more benzotriazole derivatives b1) having the following general formula (C) and combinations thereof:
[0000]
[0000] wherein R 1 is C 1 -C 12 alkyl; C 1 -C 5 alkoxy; C 1 -C 5 alkoxycarbonyl; C 5 -C 7 cycloalkyl; C 6 -C 10 aryl; or aralkyl;
R 3 is hydrogen; C 1 -C 5 alkyl; C 1 -C 5 alkoxy; halogen, preferably chlorine; or hydroxy;
m is 1 or 2;
when m=1, R 2 is hydrogen; unsubstituted or phenyl-substituted C 1 -C 12 alkyl; or C 6 -C 10 aryl;
when m=2, R 2 is a direct bond between the phenyl groups; or —(CH 2 ) p —;
and p is from 1 to 3.
[0021] By “combination thereof”, it is generally understood that when more than one stabilizers of the one or more benzotriazole derivatives b1), for example, are present in the polyester composition, the different stabilizers b1) can have different structures and can be independently selected from the general formula (C), all of these stabilizers having the general formula (C).
[0022] More preferably, the one or more benzotriazole derivatives b1) have the following general formula (D) and combinations thereof:
[0000]
[0000] wherein R 1 is an C 1 -C 12 alkyl.
[0023] Still more preferably, the one or more benzotriazole derivatives b1) have the following general formula (E):
[0000]
[0000] which benzotriazole derivative is 2,2′-methylenebis(6-(2H-benzotriazol-2-yl)-4-1,1,3,3-tetramethylbutyl)-phenol ((CAS number: 103597-45-1; also referred to 2,2′-methylenebis(6-(benzotriazol-2-yl)-4-tert-octylphenol)).
[0024] Preferably, the one or more benzotriazole derivatives b1) are present in an amount from at or about 0.01 to at or about 2.98 wt-%, more preferably from at or about 0.05 to at or about 2 wt-% and still more preferably from at or about 0.1 to at or about 1 wt-%, provided that the sum of b1)+b2)+b3) is between 0.3 and 3 wt-%, the weight percentage being based on the total weight of the polyester composition.
[0025] Preferably, one of the three UV stabilizers is one or more triazine derivatives and/or pyrimidine derivatives b2) having the following general formula (F) and combinations thereof:
[0000]
[0000] wherein Y is N (triazine derivative) or CH (pyrimidine derivative); and wherein R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, halogen, haloalkyl, alkoxy, alkylene, aryl, alkyl-aryl, or a combination thereof.
[0026] More preferably, the one or more triazine derivatives and/or pyrimidine derivatives b2) are triazine derivatives, i.e. Y is N (nitrogen), of the following formula (G) and combinations thereof:
[0000]
[0000] wherein R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, halogen, haloalkyl, alkoxy, alkylene, aryl, alkyl-aryl, or a combination thereof.
[0027] Still more preferably, the one or more triazine derivatives and/or pyrimidine derivatives b2) are compounds of the following general formula (H):
[0000]
[0000] which triazine derivatives and/or pyrimidine derivatives is 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxy-phenol (CAS Nb 147315-50-2).
[0028] Preferably, the one or more triazine derivatives and/or pyrimidine derivatives b2) are present in an amount from at or about 0.01 to at or about 2.98 wt-%, more preferably from at or about 0.05 to at or about 2 wt-% and still more preferably from at or about 0.1 to at or about 1 wt-%, provided that the sum of b1)+b2)+b3) is between 0.3 and 3 wt-%, the weight percentage being based on the total weight of the polyester composition.
[0029] Preferably, one of the three UV stabilizers is one or more benzotriazole derivatives b1) having the following general formulas (I) and combinations thereof:
[0000]
[0000] wherein R 12 , R 13 , R 14 , R 15 and R 16 are each independently selected from the group consisting of hydrogen, ether groups, ester groups, amine groups, amide groups, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, cycloalkyl groups, aryl groups or a combination thereof; in which the substituents in turn may contain functional groups; examples of functional groups are alcohols, ketones, anhydrides, imines, siloxanes, ethers, carboxyl groups, aldehydes, esters, amides, imides, amines, nitriles, ethers, urethanes and any combination thereof. The one or more hindered amine derivatives may also form part of a polymer or oligomer.
[0030] More preferably, the one or more hindered amine derivatives b3) are compounds derived from a substituted piperidine compound, in particular any compound derived from an alkyl-substituted piperidyl, piperidinyl or piperazinone compound, and substituted alkoxypiperidinyl compounds. Still more preferably, the one or more hindered amine derivatives b3) are an oligomer of N-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol and succinic acid, which oligomer has a molecular weight M n of 3100-4000. (CAS number: 65447-77-0).
[0031] Preferably, the one or more hindered amine derivatives b3) are present in an amount from at or about 0.01 to at or about 2.98 wt-%, more preferably from at or about 0.05 to at or about 2 wt-% and still more preferably from at or about 0.1 to at or about 1 wt-%, provided that the sum of b1) b2) b3) is between 0.3 and 3 wt-%, the weight percentage being based on the total weight of the polyester composition.
[0032] According to a preferred embodiment, the at least three UV stabilizers are:
[0000] b1) being 2,2′-methylenebis(6-(2H-benzotriazol-2-yl)-4-1,1,3,3-tetramethylbutyl)-phenol,
b2) being 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxy-phenol, and
b3) being an oligomer of N-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol and succinic acid.
[0033] The polyester composition according to the present invention comprises one or more reinforcing agents. Preferably, the one or more reinforcing agents are selected from one or more glass reinforcing agents, one or more inert fillers and mixtures thereof.
[0034] Examples of glass reinforcing agents include without limitation non-circular cross-sectional fibrous glass fillers; glass fibers having a circular cross section and glass flakes. Non-circular cross-sectional fibrous glass fillers are fibrous glass fillers characterized by a non-circular cross section. The non-circular cross section have the shape of, for example, an oval, elliptic, cocoon or rectangular. Particularly preferred non-circular cross-sectional fibrous glass fillers are those having a non-circular cross-sectional aspect ratio of at or about 4. These kinds of non-circular cross-sectional fibrous glass filler are described and differentiated from conventional glass fillers by their cross-sectional aspect ratio and are differentiated from conventional glass flakes by their fibrous nature. The term “fibrous” in the context of the invention means composed of one or multiple filaments of glass. The “cross-sectional aspect ratio” is measured by cutting the fibrous glass filler perpendicularly to its longitudinal axis and measuring the ratio between the major axis of the cross section (i.e. its longest linear dimension) and the minor axis of the cross section (i.e. its shortest linear dimension perpendicular to the major axis). For comparison, glass fibers having a circular cross-section have a cross-sectional aspect ratio of about 1. Glass flakes fillers are differentiated from non-circular cross-sectional glass filler by their non-fibrous nature. Such non-circular cross-sectional fibrous glass fillers and poly(butylene)terephthalate compositions comprising such fillers are described in EP 0190011, EP 196194, EP 400935, EP 0246620, JP 03263457 and JP 03220260.
[0035] Examples of inert fillers include without limitation calcium carbonate, carbon fibers, talc, mica, wollastonite, calcinated clay, kaolin, magnesium sulfate, magnesium silicate, barium sulphate, titanium dioxide, sodium aluminum carbonate, barium ferrite and potassium titanate.
[0036] The one or more reinforcing agents are present in an amount from at or about 1 to at or about 60 wt-%, preferably from at or about 5 to at or about 50 wt-%, or more preferably from at or about 10 to at or about 50 wt-%, the weight percentages being based on the total weight of the polyester composition.
[0037] In an attempt to further improve heat aging characteristics, the polyester composition according to the present invention may further comprise one or more oxidative stabilizers (also referred as antioxidants or heat stabilizers). Preferably, the one or more oxidative stabilizers are selected from phenolic-based stabilizers, phosphorus-based stabilizers, hindered amine stabilizers, aromatic amine stabilizers, thioesters and mixtures thereof so as to hinder thermally induced oxidation of polyesters where high temperature applications are used. More preferably, the one or more oxidative stabilizers are selected from phenolic-based stabilizers, phosphorus-based stabilizers and mixtures thereof. Preferred examples of phenolic-based antioxidants are sterically hindered phenols. Preferred examples of phosphorus-based antioxidants are phosphite stabilizers, hypophosphite stabilizers and phosphonite stabilizers and more preferably diphosphite stabilizers. When present, the one or more oxidative stabilizers comprise from at or about 0.1 to at or about 3 wt-%, or preferably from at or about 0.1 to at or about 1 wt-%, or more preferably from at or about 0.1 to at or about 0.8 wt-%, the weight percentages being based on of the total weight of the polyester composition.
[0038] The polyester composition according to the present invention may further comprise one or more flame retardants (also referred to in the art as flameproofing agents). Flame retardants are used in thermoplastic compositions to suppress, reduce, delay or modify the propagation of a flame through the composition or an article based on the composition. The one or more flame retardants may be halogenated flame retardants inorganic flame retardants, phosphorous containing compounds and nitrogen containing compounds or a combination thereof.
[0039] Halogenated organic flame retardants include without limitation chlorine- and bromine-containing compounds. Examples of suitable chlorine-containing compounds include without limitation chlorinated hydrocarbons, chlorinated cycloaliphatic compounds, chlorinated alkyl phosphates, chlorinated phosphate esters, chlorinated polyphosphates, chlorinated organic phosphonates, chloroalkyl phosphates, polychlorinated biphenyls and chlorinated paraffins. Examples of suitable bromine-containing compounds include without limitation tetrabromobisphenol A, bis(tribromophenoxy)alkanes, polybromodiphenyl ethers, brominated phosphate esters tribromophenol, tetrabromodiphenyl sulfides, polypentabromo benzyl acrylate, brominated phenoxy resins, brominated polycarbonate polymeric additives based on tetrabromobisphenol A, brominated epoxy polymeric additives based on tetrabromobisphenol A and brominated polystyrenes.
[0040] Inorganic flame retardants include without limitation metal hydroxides, metal oxides, antimony compounds, molybdenum compounds and boron compounds. Examples of suitable metal hydroxides include without limitation magnesium hydroxide, aluminum hydroxide, aluminum trihydroxide and other metal hydroxides. Examples of suitable metal oxides include without limitation zinc and magnesium oxides. Examples of suitable antimony compounds include without limitation antimony trioxide, sodium antimonite and antimony pentoxide. Examples of suitable molybdenum compounds include without limitation molybdenum trioxide and ammonium octamolybdate (AOM). Examples of suitable boron compounds include without limitation include zinc borate, borax (sodium borate), ammonium borate and calcium borate.
[0041] Examples of suitable phosphorous containing compounds include without limitation red phosphorus; halogenated phosphates; triphenyl phosphates; oligomeric and polymeric phosphates; phosphonates phosphinates, disphosphinate and/or polymers thereof.
[0042] Examples of suitable nitrogen containing compounds include without limitation triazines or derivatives thereof, guanidines or derivatives thereof, cyanurates or derivatives thereof and isocyanurates or derivatives thereof.
[0043] When present, the one or more flame retardants comprise from at or about 5 to at or about 30 wt-%, or preferably from at or about 10 to at or about 25 wt-%, the weight percentages being based on of the total weight of the polyester composition.
[0044] Depending on the end-use application, the polyester composition may further comprise one or more hydrolysis stabilizers such as for example epoxy-containing compounds. Examples of suitable epoxy-containing compounds include without limitation an epoxy containing polyolefin, a glycidyl ether of polyphenols, a bisphenol epoxy resin and an epoxy novolac resin. Epoxy containing polyolefins are polyolefins, preferably polyethylene, that are functionalized with epoxy groups; by “functionalized”, it is meant that the groups are grafted and/or copolymerized with organic functionalities. Examples of epoxides used to functionalize polyofins are unsaturated epoxides comprising from four to eleven carbon atoms, such as glycidyl(meth)acrylate, allyl glycidyl ether, vinyl glycidyl ether and glycidyl itaconate, glycidyl(meth)acrylates (GMA) being particularly preferred. Ethylene/glycidyl(meth)acrylate copolymers may further contain copolymerized units of an alkyl (meth)acrylate having from one to six carbon atoms and an α-olefin having 1-8 carbon atoms. Representative alkyl(meth)acrylates include methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl (meth)acrylate, isobutyl(meth)acrylate, hexyl(meth)acrylate, or combinations of two or more thereof. Of note are ethyl acrylate and butyl acrylate. Bisphenol epoxy resins are condensation products having epoxy functional groups and a bisphenol moiety. Examples include without limitation products obtained from the condensation of bisphenol A and epichlorohydrin and products obtained from the condensation of bisphenol F and epichlorohydrin. Epoxy novolac resins are condensation products of an aldehyde such as for example formaldehyde and an aromatic hydroxyl-containing compound such as for example phenol or cresol. When present, the one or more epoxy-containing compounds are present in an amount sufficient to provide from at or about 3 to at or about 300 milliequivalents of total epoxy function per kilogram of polyester, preferably from at or about 5 to at or about 300 milliequivalents of total epoxy function per kilogram of polyester.
[0045] The polyester composition according to the present invention may further comprise one or more tougheners. The toughener will typically be an elastomer having a relatively low melting point, generally lower than 200° C., preferably lower than 150° C. and that has attached to it functional groups that can react with the polyester (and optionally other polymers present). Since polyester resins usually have carboxyl and hydroxyl groups present, these functional groups usually can react with carboxyl and/or hydroxyl groups. Examples of such functional groups include epoxy, carboxylic anhydride, hydroxyl (alcohol), carboxyl, and isocyanate. Preferred functional groups are epoxy, and carboxylic anhydride, and epoxy is especially preferred. Such functional groups are usually “attached” to the polymeric tougheners by grafting small molecules onto an already existing polymer or by copolymerizing a monomer containing the desired functional group when the polymeric tougheners molecules are made by copolymerization. As an example of grafting, maleic anhydride may be grafted onto a hydrocarbon rubber using free radical grafting techniques. The resulting grafted polymer has carboxylic anhydride and/or carboxyl groups attached to it. An example of a polymeric toughener wherein the functional groups are copolymerized into the polymer is a copolymer of ethylene and a (meth)acrylate monomer containing the appropriate functional group. By (meth)acrylate herein is meant the compound may be either an acrylate, a methacrylate, or a mixture of the two. Useful (meth)acrylate functional compounds include (meth)acrylic acid, 2-hydroxyethyl(meth)acrylate, glycidyl(meth)acrylate, and 2-isocyanatoethyl(meth)acrylate. In addition to ethylene and a functional (meth)acrylate monomer, other monomers may be copolymerized into such a polymer, such as vinyl acetate, unfunctionalized (meth)acrylate esters such as ethyl(meth)acrylate, n-butyl(meth)acrylate, and cyclohexyl(meth)acrylate. Preferred toughening agents include those listed in U.S. Pat. No. 4,753,980, which is hereby incorporated by reference. Especially preferred tougheners are copolymers of ethylene, ethyl acrylate or n-butyl acrylate, and glycidyl methacrylate, such as EBAGMA and ethylene/methyl acrylate copolymers. It is preferred that the polymeric toughener, if used, contain from at or about 0.5 to at or about 20 wt-% of repeat units derived from monomers containing functional groups, preferably from at or about 1.0 to at or about 10 wt-%, more preferably from at or about 7 to at or about 13 wt-% of repeat units derived from monomers containing functional groups. There may be more than one is type of repeat unit derived from functionalized monomer present in the polymeric toughener. It has been found that toughness of the composition is increased by increasing the amount of polymeric toughener and/or the amount of functional groups. However, these amounts should preferably not be increased to the point that the composition may crosslink, especially before the final part shape is attained.
[0046] The polymeric toughener may also be ionomers. Ionomers are thermoplastic resins that contain metal ions in addition to the organic backbone of the polymer. Ionomers are ionic copolymers formed from an olefin such as ethylene and α,β-unsaturated C 3 -C 8 carboxylic acid, such as for example acrylic acid (AA), methacrylic acid (MAA) or maleic acid monoethylester (MAME), wherein at least some of the carboxylic acid moieties, preferably form 10 to 99.9%, in the copolymer are neutralized to form the corresponding carboxylate salts. Preferably, the one or more ionomers contain from about 5 to about 30 wt-% of acrylic acid, methacrylic acid and/or maleic acid monoethylester, the weight percentage being based on the total weight of the ionomer. Neutralizing agents are alkali metals like lithium, sodium or potassium or transition metals like manganese or zinc. Compounds suitable for neutralizing an ethylene acid copolymer include ionic compounds having basic anions and alkali metal cations (e.g. lithium or sodium or potassium ions), transition metal cations (e.g. zinc ion) or alkaline earth metal cations (e.g. magnesium or calcium ions) and mixtures or combinations of such cations. Ionic compounds that may be used for neutralizing the ethylene acid copolymers include alkali metal formates, acetates, nitrates, carbonates, hydrogen carbonates, oxides, hydroxides or alkoxides. Other useful ionic compounds include alkaline earth metal formates, acetates, nitrates, oxides, hydroxides or alkoxides of alkaline earth metals. Transition metal formates, acetates, nitrates, carbonates, hydrogen carbonates, oxides, hydroxides or alkoxides may also be used. Preferred neutralizing agents are sources of sodium ions, potassium ions, zinc ions, magnesium ions, lithium ions, transition metal ions, alkaline earth metal cations and combinations of two or more thereof, sodium ions being more preferred.
[0047] The polymeric toughener may also be thermoplastic acrylic polymers that are not copolymers of ethylene. The thermoplastic acrylic polymers are made by polymerizing acrylic acid, acrylate esters (such as methyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, n-hexyl acrylate, and n-octyl acrylate), methacrylic acid, and methacrylate esters (such as methyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate (BA), isobutyl methacrylate, n-amyl methacrylate, n-octyl methacrylate, glycidyl methacrylate (GMA) and the like). Copolymers derived from two or more of the forgoing types of monomers may also be used, as well as copolymers made by polymerizing one or more of the forgoing types of monomers with styrene, acryonitrile, butadiene, isoprene, and the like. Part or all of the components in these copolymers should preferably have a glass transition temperature of not higher than 0° C. Preferred monomers for the preparation of a thermoplastic acrylic polymer toughening agent are methyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, n-hexyl acrylate, and n-octyl acrylate. It is preferred that a thermoplastic acrylic polymer toughening agent have a core-shell structure. The core-shell structure is one in which the core portion preferably has a glass transition temperature of 0° C. or less, while the shell portion is preferably has a glass transition temperature higher than that of the core portion. The core portion may be grafted with silicone. The shell section may be grafted with a low surface energy substrate such as silicone, fluorine, and the like. An acrylic polymer with a core-shell structure that has low surface energy substrates grafted to the surface will aggregate with itself during or after mixing with the thermoplastic polyester and other components of the composition of the invention and can be easily uniformly dispersed in the composition.
[0048] When present, the tougheners preferably comprise from at or about 0.5 to at or about 15 wt-%, or more preferably from at or about 1 to at or about 10 wt-%, the weight percentages being based on the total weight of the polyester composition.
[0049] The polyester composition according to the present invention may further include modifiers and other ingredients, including, without limitation, lubricants, impact modifiers, flow enhancing additives, antistatic agents, coloring agents, nucleating agents, crystallization promoting agents and other processing aids known in the polymer compounding art.
[0050] Fillers, modifiers and other ingredients described above may be present in the polyester composition in amounts and in forms well known in the art, including in the form of so-called nano-materials where at least one of the dimensions of the particles is in the range of 1 to 1000 nm.
[0051] The polyester compositions according to the present invention are melt-mixed blends, wherein all of the polymeric components are well-dispersed within each other and all of the non-polymeric ingredients are well-dispersed in and bound by the polymer matrix, such that the blend forms a unified whole. Any melt-mixing method may be used to combine the polymeric components and non-polymeric ingredients of the present invention. For example, the polymeric components and non-polymeric ingredients may be added to a melt mixer, such as, for example, a single or twin-screw extruder; a blender; a single or twin-screw kneader; or a Banbury mixer, either all at once through a single step addition, or in a stepwise fashion, and then melt-mixed. When adding the polymeric components and non-polymeric ingredients in a stepwise fashion, part of the polymeric components and/or non-polymeric ingredients are first added and melt-mixed with the remaining polymeric components and non-polymeric ingredients being subsequently added and further melt-mixed until a well-mixed composition is obtained.
[0052] In another aspect, the present invention relates to a method for manufacturing an article comprising a step of shaping the polyester composition according to the present invention and to the shaped article made from the polyester composition of the invention. By “shaping” is meant any shaping technique, such as for example extrusion, injection molding, compression molding, blow molding, thermoforming, rotational molding and melt casting, injection molding and extrusion process being preferred.
[0053] The polyester compositions according to the present invention and articles made thereof are suited for a wide variety of uses. The polyester compositions according to the present invention and articles made thereof are particularly suited for applications where resistance against long-term weathering exposure is of concern, like for example for automotive parts, electrical/electronic parts, household appliances and furniture, structural components for machines (e.g. computers, disk drives), decorative or structural parts for building and construction application (e.g. outdoor signs, ornaments, parts of photovoltaic panels).
EXAMPLES
[0054] The following materials were used for preparing the polyester composition according to the present invention:
[0000] Polyester: poly(ethylene terephthalate) supplied by Toray Saehan, Korea under the name PET chips A9203.
Glass fibers: characterized by a nominal fiber diameter of 10 μm and a standard cut length of 4.5 mm, supplied by Owens Corning Vetrotex, France under the name Vetrotex EC10 952.
Mica: delaminated pure phlogopite mica having an equivalent spherical diameter (D90 value) of 400 microns and a median size of 250 microns, supplied by Zemex Industrial Minerals, Atlanta, Ga., USA under the trademark Suzorite® 60-HK.
UV stabilizer b1: 2,2′-methylenebis(6-(2H-benzotriazol-2-yl)-4-1,1,3,3-tetramethylbutyl)-phenol (CAS Nb 103597-45-1) supplied by Ciba Specialty Chemicals, Tarrytown, N.Y., USA under the trademark Tinuvin® 360.
UV stabilizer b2: 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxy-phenol (CAS Nb 147315-50-2) supplied by Ciba Specialty Chemicals, Tarrytown, N.Y., USA under the trademark Tinuvin® 1577.
UV stabilizer b3: oligomer of N-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol and succinic acid having a molecular weight M n of 3100-4000 (CAS number: 65447-77-0), supplied by Ciba Specialty Chemicals, Tarrytown, N.Y., USA under the trademark Tinuvin® 622.
Diphosphite based antioxidant: supplied by G.E. Specialty Chemicals, Parkersburg, W. Va., USA under the trademark Ultranox® 626.
Phenolic based antioxidant: supplied by Ciba Specialty Chemicals, Tarrytown, N.Y., USA under the trademark Irganox® 1010.
Plasticizer: polyethylene glycol 400 di-2-ethylhexanoate supplied by C.P. Hall Company, Chicago, Ill., USA under the trademark Plasthall® 809.
Ionomer: a copolymer comprising ethylene and 15 wt-% MAA (methacrylic acid), wherein 59 wt-% of the available carboxylic acid moieties are neutralized with sodium cations, supplied by E. I. du Pont de Nemours and Company, Wilmington, Del., USA under the trademark Surlyn®.
Lubricant: oxidized polyethylene wax supplied by Degussa GmbH, Düsseldorf, Germany under the trademark Vestowax® AO1535.
Epoxy resin: produced from bisphenol A and epichlorohydrin and having an epoxy equivalent weight on solids of 2273-3846 g/eq, supplied by Hexion Speciality Chemicals, Columbus, Ohio, USA under the trademark Epikote™ 1009.
Ethylene epoxide copolymer: an ethylene butyl-acrylate glycidyl methacrylate copolymer (28 wt-% BA, 5.2 wt-% GMA) supplied by E. I. du Pont de Nemours and Company, Wilmington, Del., USA under the trademark Elvaloy®.
Black carbon masterbatch: black color masterbatch based on polyethylene supplied by Cabot Corp., Boston, Mass. under the name Cabot PE-3324.
[0000] TABLE 1 E1 Polyester 51.00 glass fibers 15.00 Mica 20.00 UV stabilizer b1 0.20 UV stabilizer b2 0.40 UV stabilizer b3 0.20 diphosphite based antioxidant 0.20 phenolic based antioxidant 0.20 Plasticizer 2.90 Ionomer 3.45 Lubricant 0.90 epoxy resin 0.60 ethylene epoxide copolymer 3.27 carbon black 1.68
Ingredient quantities are given in wt-% on the basis of the total weight of the polyester composition.
[0055] The composition of the Example (E1) was prepared by melt blending the ingredients shown in Table 1 in a 40 mm twin screw kneader operating at about 260° C. using a screw speed of about 300 rpm, a melt temperature displayed of about 267° C. and a melt temperature measured by hand of about 281° C. Upon exiting the extruder, the compositions were cooled and pelletized. | The present invention relates to the field of ultraviolet light stabilized polyester compositions, particularly it relates to ultraviolet light stabilized polyester compositions for manufacturing articles having good mechanical properties and a good surface appearance upon long-term outdoor exposure and/or heat exposure. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a utility application and claims the benefit under 35 USC §119(a) of India Application No. 892/DEL/2006 filed Mar. 30, 2006. This disclosure of the prior application is considered part of and is incorporated by reference in the disclosure of this application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a single step Green Process for the Preparation of Substituted Cinnamic Esters with trans-Selectivity. The present invention particularly relates to a process of conversion of cinnamyl alcohol or cinnamaldehyde to corresponding esters directly. Cinnamic esters are commercially important products in cosmetics, lubricants, plasticizers and perfumes.
2. Background Information
Cinnamic esters are immensely important organic compounds due to their applications in a wide range of products such as cosmetics, lubricants, plasticizers and perfumes (A. Steffen, Perfume and Flavor Chemicals ( Aroma Chemicals ), Vol. I & II. Allured Publishing Corporation: IL, USA, 1994). These esters are useful as a material for perfumes, as cinnamic aldehydes, and for the synthesis of β-amyl cinnamic aldehydes and the like. These esters can themselves be used as precursors for the synthesis of polyhetroalkylene esters which can be useful as raw materials for the synthesis of perfumes, drugs and as organic synthetic intermediates and as polymerisable materials and so forth (K. Yurugi, T. Kubo, U.S. Pat. No. 6,541,656, 2003).
A number of prior arts are available for the synthesis of cinnamic esters (A. Galat, J. Am. Chem. Soc., 1946, 68, 376; V. T. Ramakrishnan, J. Kagan, J. Org. Chem., 1970, 35, 2901; H. Tanaka, S. Takamuku, H. Sakurai, Bull. Chem. Soc. Jpn., 1979, 52, 801; Y. Oikaw, T. Yoshioka, O. Yonemitsu, Tetrahedron Lett., 1982, 23, 889; U. Tataki, I. Suso, T. Matsuhisa, I. Hara, U.S. Pat. No. 4,661,620, 1987; B. Gerhard, K. Jochen, S. Werner, U.S. Pat. No. 5,124,478, 1992; Z. Wang, F. R. W. McCourt, D. A. Holden, Macromolecules, 1992, 25, 1576; T. Iliefski, S. Li, K. Lundquist, Tetrahedron Lett., 1998, 39, 2413; V. L. Pardini, S. K. Sakata, R. R. Vargas, H. Viertler, J. Braz. Chem. Soc., 2001, 12, 223; H. Weissman, X. Song, D. Milstein, J. Am. Chem. Soc., 2001, 123, 337; K. M. Bushan, G. V. Rao, T. Soujanya, V. J. Rao, S. Saha, A. Samanta, J. Org. Chem., 2001, 66, 681; A. Stadler, C. O. Kappe, Tetrahedron, 2001, 57, 3915; P. Kisnaga, B. Dsa, J. Verkade, Tetrahedron, 2001, 57, 8047; B. Deevi, J. R. Anumolu, Synth. Commun., 2002, 32, 195; C. S. Cho, D. T. Kim, H. J. Choi, T. J. Kim, S. C. Shim, Bull. Korean Chem. Soc., 2002, 23, 539; R. Borah, D. J. Kalita, J. C. Sarma, Ind. J. Chem., 2002, 41B, 1032; S. F. Jonathan, K. Hisashi, M. P. G. Gerard, J. K. T. Richard, Synlett, 2002, 8, 1293; S. Crosignani, P. D. White, B. Linclau, Org. Lett., 2002, 4, 2961; O. Uchikawa, K. Fukatsu, R. Tokunoh, M. Kawada, K. Matsumoto, Y. Imai, S. Hinuma, K. Kato, H. Nishikawa, K. Hirai, M. Miyamoto, S. Ohkawa, J. Med. Chem., 2002, 45, 4222; A. Costa, C. Nájera, J. M. Sansano, J. Org Chem., 2002, 67, 5216; W. C. Shieh, S. Dell, O. Repic, Tetrahedron Lett., 2002, 43, 5607; A. Palma, B. A. Frontana-Uribe, J. Cardenas, M. Saloma, Electrochem. Commun., 2003, 5, 455; S. Crosignani, P. D. White, R. Steinauer, B. Linclau, Org. Lett., 2003, 5, 853; H. M. S. Kumar, M. S. Kumar, S. Joyasawal, J. S. Yadav, Tetrahedron Lett., 2003, 44, 4287; N. N. Karade, S. G. Shirodkar, R. A. Potrekar, Synth. Commun., 2004, 34, 391; R. B. Andrew, C. G. IV Louis, Synlett, 2004, 738; T. J. Speed, J. P. McIntyre, D. M. Thamattoor, J. Chem. Edu. 2004, 81, 1355; D. Penningt, M. A. Russell, B. B. Chen, H. Y. Chen, B. N. Desai, S. H. Docter, D. J. Edwards, G. J. Gesicki, C. D. Liang, J. W. Malecha, S. S. Yu, V. W. Engleman, S. K. Freeman, M. L. Hanneke, K. E. Shannon, M. M. Westlin, G. A. Nickels, Bioorg. Med. Chem. Lett., 2004, 14, 1471; J. M. Concellon, H. R. Solla, C. Mejica, Tetrahedron Lett., 2004, 45, 2977; D. K. Barma, A. Kundu, A. Bandyopadhyay, A. Kundu, B. Sangras, A. Briot, C. Mioskowski, J. R. Falck, Tetrahedron Lett., 2004, 45, 5917; R. Ballini, D. Fiorini, A. Palmieri, Tetrahedron Lett., 2004, 45, 7027; G. Deng, B. Xu, C. Liu, Tetrahedron, 2005, 61, 5818). The most common being acid catalysed esterification of the cinnamic acids in the presence of appropriate alcohols ((a) I. A. Pearl, D. L. Beyer, J. Org. Chem., 1951, 16, 216; (b) L. H. Klemm, R. A. Klemm, P. S. Santhanam, D. V. White, J. Org. Chem., 1971, 36, 2169; (c) B. Botta, G. D. Monache, M. C. De Rosa, A. Carbonetti, E. Gacs-Baitz, M. Botta, F. Corelli, D. Misiti, J. Org. Chem., 1995, 60, 3657; (d) A. Ewenson, B. Croitoru, A. Shushan, U.S. Pat. No. 728,865, 1998; (e) A. M. S. Silva, I. Alkorta, J. Elguero, V. L. M. Silva, J. Mol. Struct., 2001, 595), however, the reaction is reversible and the acids employed may not be compatible with many sensitive functional groups attached at either the aromatic ring or the alkyl chains such as alkoxy, halogens and the like.
Similarly, Org. Synth. Coll. Vol. 1, 252, discloses a method for the preparation of ethyl cinnamate by reaction of benzaldehyde, ethylacetate and ethanol and sodium as dispersed pieces. However, the process suffers from the use of highly inflammable sodium. Another conventional approach for the synthesis of cinnamates is the Claisen condensation between benzaldehydes and acetic acid esters (A. I. Vogel, A Textbook of Practical Organic Chemistry, Richard Clay (The Chaucer Press), Ltd., Bungay, Suffolk, 1978) in the presence of a strong base such as sodium salts of acetic acids and again the method has limitation for a number of substituted benzaldehydes. Moreover, the reactions are reported to take invariably long time for completion which adds to the mundane of the chemists and unnecessarily utilize energy resources in industries.
Heck came up with a different route for the synthesis of α,β-unsaturated acids (Heck. et al., J. Amer. Chem. Soc., 1969, 6707) by reaction between aryl halides and aryl acrylate using palladium acetate and a base as catalyst. Although, the method provided good yield of the product, it still suffers from expensive reagents used in the reaction.
Another modification of Heck reaction came in the form of Stille reaction (Stille et al., J. Amer. Chem. Soc., 1976, 1806) wherein alkyl boronic acids are being taken as the substrates and are reacted with aryl halides. However, the reaction also requires presence of copper salts (II) in stoichiometric amounts as oxidants in these reactions.
The following prior art references are disclosed:
Commetti and Chiusoli ( J. Organometal. Chem., 1979, 181, C14) discloses a method for synthesis of methyl cinnamate by reaction of styrene, carbon monoxide and methanol in the presence of palladium as catalyst, but again it has a shortfall in terms of use of excess Cu (II) salt as oxidant which renders the process industrially unviable.
Similarly, many patents disclose the method for the preparation of cinnamic esters as discussed below:
J.P. Pat. No. 21342 discloses a method for the production of methyl cinnamate through oxidative carbonylation of styrenes wherein it was further disclosed that use of an excess dehydrating agent may cause increase in the yield the product and good yields could be obtained. However, use of excess dehydrating agent was an impediment in this transformation.
J.P. Pat. No. 21343 discloses a method for the production of methyl cinnamates by reacting styrenes, aliphatic alcohols, carbon monoxide and palladium but again the method has its drawback in the form of using expensive dehydrating agent.
U.S. Pat. No. 4,737,591, 1988 discloses a method for the cinnamate derivatives by reacting styrenes, aliphatic alcohols, carbon monoxide, palladium chloride and copper salt without any dehydrating agent, but poor yield of the product was obtained.
D.E. Pat. No. 7,099,227 discloses a method for the preparation of ethyl cinnamate by condensing benzaldehyde and ethyl acetate in the presence of sodium hydride as a base. Sodium hydride, however, is not easy to handle and is expensive and so the process demands improvement.
U.S. Pat. No. 4,618,698, 1986 discloses a method for the preparation of optionally substituted cinnamic acid by treatment of optionally substituted benzaldehyde and acetic acid ester and alcohol to form an optionally substituted cinnamic acid ester as well as alkoxy phenyl propionic acid which then was hydrolyzed into optionally substituted cinnamic acid. This was finally esterified to provide the cinnamic ester. The reaction suffers from tedius of multi step synthesis and demands rectification.
U.S. Pat. No. 6,054,607, 2000 discloses a method for the preparation of cinnamic acid esters by condensing a benzaldehyde with an acetic acid ester in the presence of a base followed by treatment with an acid to form alkoxy phenylpropionic acid ester which is then treated with an acid to provide the cinnamic ester. In addition, many patents (U.S. Pat. Nos. 3,381,030, 3,397,225, 3,397,226, 3,530,168, 3,621,054) also discloses the method for the preparation of cinnamic esters. Though, the many above mentioned methods provide good yield of the product, the reaction conditions are not mild and resort to ultra low temperature there by making it difficult to control the reaction.
In 1968, Corey, Gilman and Ganem presented a unique approach of converting α,β-unsaturated aldehydes directly into their methyl esters using manganese dioxide, sodium cyanide and acetic acid in methanol (E. J. Corey, N. W. Gilman, B. E. Ganem, J. Am. Chem. Soc., 1968, 90, 5616). This revolutionary method made a remarkable impact in organic chemistry and has been instrumental in the synthesis of various complex natural products (E. J. Corey, J. A. Katzenenllenbogen, N. W. Gilmen, S. A. Romen, B. W. Erickson, J. Am. Chem. Soc., 1968, 90, 5618; A. D. Adams, R. H. Schlessinger, J. R. Tata, J. J. Venit, J. Org. Chem., 1986, 51, 3070).
The above method continued to attract the attention of researchers for direct conversion of aldehydes or alcohols into esters and various prior arts are available for this conversion using a range of reagents such as MnO 2 —NaCN (A. B. III Smith, G. A. Sulikowski, M. M. Sulikowski, K. Fujimoto, J. Amer. Chem. Soc., 1992, 114, 2567; J. S. Foot, H. Kanno, G. M. P. Giblin, R. J. K. Taylor, Synlett, 2002, 1393), chromium oxide-pyridine (E. J. Corey, B. Samuelsson, J. Org. Chem., 1984, 49, 4735), t-butyl hypochlorite (J. N. Milovanovic, M. Vasojevic, S. Gojkovic, J. Chem. Soc. Perkin Trans 2, 1991, 1231) and PhIO—KBr (H. Tohma, T. Maegawa, Y. Kita, Synlett, 2003, 723) etc. There are other prior arts such as Tetrahedron Lett., 1982, 23, 4647; Tetrahedron, 1982, 38, 337; J. Org. Chem., 1968, 33, 2525; J. Amer. Chem. Soc., 1976, 98, 1629 etc for the preparation of esters.
Although methods for direct conversion of cinnamaldehyde (C 6 -C 3 unit) or cinnamyl alcohol (C 6 -C 3 unit) into cinnamic esters (C 6 -C 3 unit) are meritorious but have certain limitations. First, all these methods pass through an intermediate C 6 -C 4 unit, formed by combination of substrate C 6 -C 3 unit and an extra C 1 unit in the form of sodium/potassium cyanide or TMSCN (B. S. Bal, W. E. Childers Jr., H. W. Pinnick, Tetrahedron, 1981, 37, 2091; A. D. Adams, R. H. Schlessinger, J. R. Tata, J. J. Venit, J. Org. Chem., 1986, 51, 3070) etc. and overall, the protocols confer lack of atom economy. Secondly, use of hazardous cyanide reagents make the process more and more unviable for industrial use. In the contemporary concerns for Green chemistry, there has been a tremendous upsurge of interest in various chemical transformations mediated by Green technologies (T. J. Mason, P. Cintas in Handbook Of Green Chemistry and Technology (Eds.: J. Clark, D. Macquarrie), Blackwell Publishing, 2002, pp. 372) such as atom economical processes, reactions in aqueous media, reusable heterogeneous catalysts, use of ultrasound and microwave (B. L. Hayes, Microwaves Synthesis: Chemistry at the Speed of Light , CEM Publishing: Matthews N.C., 2002; N. F. K. Kaiser, U. Bremberg, M. Larhed, C. Moberg, A. Hallberg, Angew. Chem. Int. Ed., 2000, 39, 3596; P. Lidstrom, J. Tierney, B. Wathey, J. Westman, Tetrahedron, 2001, 57, 9225; M. Larhed, A. Hallberg, Drug Discov. Today, 2001, 6, 406; A. K. Bose, M. S. Manhas, S. N. Ganguly, A. H. Sharma, B. K. Banik, Synthesis, 2002, 11, 1578; K. J. Watkins, Chem. Eng. News, 2002, 80, 17; N. E. Leadbeater, H. M. Torenius, J. Org. Chem., 2002, 67, 3145; L. Botella, C. Nájera, Tetrahedron Lett., 2004, 60, 5563; N. Kaval, W. Dehaen, P. Mátyus, E. V. Eycken, Green Chem., 2004, 6, 125; V. Pathania, A. Sharma, A. K. Sinha, Helv. Chim. Acta, 2005, 88, 811; B. P. Joshi, A. Sharma, A. K. Sinha, Tetrahedron, 2005, 61, 3075) for organic transformations.
Cinnamic esters are of immense importance in organic chemistry due to synthetic utility ((a) T. Ohno, Y. Ishino, Y. Sumagari, I. Nishiguchi, J. Org. Chem., 1995, 60, 458; (b) B. Botta, G. D. Monache, M. C. De Rosa, A. Carbonetti, E. Gacs-Baitz, M. Botta, F. Corelli, D. Misiti, J. Org. Chem., 1995, 60, 3657; (c) F. Xu, R. D. Tillyer, D. M. Tschaen, E. J. J. Grabowski, P. J. Reider, Tetrahedron Asymmetry, 1998, 9, 1651; (d) M. Carmignani, A. R. Volpe, F. D. Monache, B. Botta, R. Espinal, S. C. De Bonnevaux, C. De Luca, M. Botta, F. Corelli, A. Tafi, G. Ripanti, G. D. Monache, J. Med. Chem., 1999, 42, 3116; (e) G. Li, H. X. Wei, S. H. Kim, Org. Lett., 2000, 2, 2249; (f) H. X. Wei, S. H. Kimm, G. Li, Tetrahedron, 2001, 57, 3869; (g) G. Li, H. X. Wei, S. H. Kim, Tetrahedron, 2001, 57, 8407; (h) R. K. Lamni, A. Ambroise, T. Balasubramanian, R. W. Wagner, D. F. Bocian, D. Holten, J. Lindsey, J. Amer. Chem. Soc., 2002, 122, 7579) of the ensuing cinnamic esters beside their applications in a wide range of products such as cosmetics, lubricants, plasticizers and perfumes (A. Steffen, Perfume and Flavor Chemicals ( Aroma Chemicals ), Vol. I & II. Allured Publishing Corporation: IL, USA, 1994). More importantly, these esters possess a variety of pharmacological activities including antioxidant (J. Chalas, C. Claise, M. Edeas, C. Messaoudi, L. Vergnes, A. Abella, Biomed. Pharmacother., 2001, 55, 54), glycosidase inhibiton (A. Sirichai, S. Kasem, R. Sophon, P. Amom, N. Nattaya, C. Warinthom, D. Sujitra, Y. A. Sirintom, Bioorg. Med. Chem. Lett., 2004, 14, 2893), and steroidogenesis inhibition activities (S. Gobec, M. Sova, K. Kristan, T. L. Rizner, Bioorg. Med. Chem. Lett., 2004, 14, 3933). For example, 17b-hydroxysteroid dehydrogenases (17b-HSDs), involved in the synthesis of active 17b-hydroxy-forms (such as estradiol, testosterone, and dihydrotestosterone) using NAD(P)H or NAD(P) as cofactor, play a key role in hormonal regulation and function in the human and constitute emerging therapeutic targets for the control of estrogeno- and androgeno-sensitive diseases like breast cancer, endometrial cancer, prostate cancer, benign prostatic hyperplasia, acne, hair loss, etc. 17b-HSDs are implicated also in the development of polycystic kidney disease, pseudohermaphroditism, Zellweger syndrome and Alzheimer's disease ((a) J. Adamski, J. F. Jakob, Mol. Cell. Endocrinol., 2001, 171, 1; (b) H. Peltoketo, V. Luu-The, J. Simard, J. Adamski, J. Mol. Endocrinol., 1999, 23, 1). Similarly, α-glucosidase inhibitors have been shown to be potentially valuable for treatment of various diseases. These α-glucosidase inhibitors are known to be promising as anti-viral, anti-HIV agents, which alter glycosidation of envelope glycoprotein through interference with biosynthesis of N-linked oligosaccharides (P. B. Fischer, G. B. Karlsson, T. D. Butters, R. A. Dwek, F. M. J. Platt, Virol., 1996, 70, 7143; (b) B. D. Walker, M. Kowalski, W. C. Goh, K. Kozarsky, M. Krieger, C. Rosen, L. Rohrschneider, W. A. Haseltine, J. Sodroski, Proc. Natl. Acad. Sci. USA., 1987, 84, 8120). In addition, they have recently been used for treatment of B- and C type viral hepatitis (T. M. Block, X. Y. Lu, F. M. Platt, G. R. Foster, W. H. Gerlich, B. S. Blumberg, R. A. Dwek, Proc. Natl. Acad. Sci. U.S.A., 1994, 91, 2235). A number of cinnamic acids and esters have been reported to be active α-glucosidase inhibiting agents (S. Adisakwattana, K. Sookkongwaree, S. Roengsumran, A. Petsom, N. Ngamrojnavanich, W. Chavasiri, S. Deesamerc, S. Y. -Anuna, Bioorg. Med. Chem. Lett., 2004, 14, 2893).
Similarly, the higher esters of substituted cinnamic acids, particularly the octyl methoxy cinnamates, are well known sunscreen agents which possess high absorption in the 300-400 nm range and which are ideally suited for cosmetic applications since they are non-irritating to the skin and provide lubricity to prevent drying effects of wind and sun (A. Alexander, R. K. Chaudhari, U.S. Pat. No. 5,527,947, 1996). Moreover, cinnamic acids and cinnamates are used as a material for perfumes, as cinnamic aldehydes, cyclamen aldehyde, beta-amyl cinnamic aldehyde and the like.
There are a number of methods available for the synthesis of cinnamic esters as being discussed in detail in the prior art section. But all of the reported inventions suffer from expensive reagents, and substrates, low yields, long reaction periods, multi-steps approach, many bye-products, hazardous reagents and chemicals, all of which combinedly call for an improved method for the synthesis of cinnamic esters. In recent years, there has been a tremendous upsurge of interest in various chemical transformations mediated by reusable heterogeneous catalysts due to environmental and economical considerations ((a) P. Laszlo, Acc. Chem. Res., 1986, 19, 121; (b) S. V. Ley, I. R. Baxendale, R. N. Bream, P. S. Jackson, A. G. Leach, D. A. Longbottom, M. Nesi, J. S. Scott, R. J. Storter, S. J. Taylor, J. Chem. Soc., Perkin Trans. I, 2000, 3815; (c) R. Fricke, H. Hosslick, G. Lischke, M. Richter, Chem. Rev., 2000, 100, 2303. (d) R. Ballini, G. Bosica, R. Maggi, A. Mazzacani, P. Righi, G. Sartori, Synthesis, 2001, 12, 1826). Reactions assisted by heterogeneous catalysis have revolutionized the organic synthesis due to higher yields, easy work up and recyclability of the catalysts.
In our constant endeavor towards synthesis of important bioactive compounds ((a) A. K. Sinha, B. P. Joshi, R. Acharya, Chem. Lett., 2003, 32, 780; (b) A. Sharma, B. P. Joshi, A. K. Sinha, Bull. Chem. Soc. Jpn., 2004, 77, 2231; (c) V. Pathania, A. Sharma, A. K. Sinha, Helv. Chim. Acta, 2005, 88, 811), we were interested to develop conversion methodologies for commercially available economical cinnamaldehydes or cinnamyl alcohols into important bioactive cinnamates.
In this context, we, herein, disclose, a convenient and efficient green process for the preparation of various aryl or alkyl cinnamates under conventional, microwave and ultrasound directly from cinnamaldehydes or cinnamyl alcohols in the presence of an oxidizing agent, catalyst and an alcohol, with or without an organic solvent.
OBJECTIVES OF THE INVENTION
The main object of the present invention is to provide a green process for the preparation of substituted cinnamic esters with trans-selectivity.
Another object of the present invention is to develop a convenient and green process for the direct oxidation of cinnamaldehydes or cinnamyl alcohols into cinnamic esters.
Yet another object of the present invention is to develop a process which may be carried out without organic solvents depending upon the alcohol used.
Yet another object of the present invention is to develop a simple process for the preparation of cinnamic esters in high purity with minimum formation of side products.
Yet another object of the present invention is to employ eco-friendly protocols as recyclable reagents, microwave and ultrasound for the preparation of product.
Still another object of the present invention is to develop a green process, in which heterogeneous catalyst used for carrying out the reaction is recyclable and reused for a number of times preferably 5 to 15 times, without any significant loss in the activity.
Yet another object of the present invention is to avoid use of any toxic and hazardous compound such as cyanides in the protocol.
Yet another object of the present invention is to develop a process for easy workup as well as purification of the product.
Still another object of the present invention is to develop a process, which requires economical chemical reagents.
Yet another object of the present invention is to develop a process for the formation of products to be used in flavor, perfumery, pharmaceutical and cosmetic industries.
Yet another object of the present invention is to develop a convenient process for the preparation of anti-cancer compound such as sintenin.
Yet another object of the present invention is to prepare high valued octyl methoxy cinnamate, an important sunscreening agent and UV filter.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a green process for the direct conversion of cinnamaldehydes or cinnamyl alcohols into various alkyl or aryl substituted cinnamic esters with exclusively E-stereoselectivity. The obtained cinnamic esters, have enormous importance in flavor, perfumery, pharmaceutical and cosmetic industries besides their role as intermediates for synthesis of various biologically active compounds. The method for this transformation is extremely simple and involves reaction of the cinnamaldehydes or cinnamyl alcohols with an oxidizing agent and a catalyst, with suitable alcohol with or without an organic solvent by stirring at room temperature or refluxing or under microwave or ultrasound irradiation for 1 min to 20 hours to get the requisite products. The oxidant for this process is selected from a group consisting of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) or chloranil or SeO 2 and the like. The catalyst is selected from group consisting of homogeneous inorganic or organic catalysts such as hydrochloric acid, sulphuric acid, nitric acid, formic acid, acetic acid, propionic acid, oxalic acid, ionic liquid and the like or heterogeneous catalyst such as AMBERLYST® 15, AMBERLITE® IR 120, AMBERLITE® IR 400, silica gel, alumina (acidic, basic and neutral), celite, kieselguhar and K-10 montmorillonite and the like. The alcohol used for esterification is selected from a group consisting of aliphatic or aromatic alcohols such as methanol, ethanol, propanol, 2-propanol, n-propyl alcohol, butanol, octanol, dodecanol, cinnamyl alcohol, benzyl alcohol, phenyl propanol, phenyl butanol and the like. The process is carried out with or without an organic solvent. Organic solvent, wherever used, is selected from a group consisting toluene, dichlorobenzene, xylene, dichloromethane, diphenyl ether, dioxane, ethylacetate, chloroform and the like. The final products are obtained in stereoselectively trans fashion in high yield varying from 51-98% depending upon the nature of substrate and reagent mixture.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is 1 H NMR (300 MHz) spectra of Dodecyl 3-(phenyl)-2-propenoate (in CDCl 3 ).
FIG. 2 is 13 C NMR (75.4 MHz) spectra of Dodecyl 3-(phenyl)-2-propenoate (in CDCl 3 ).
FIG. 3 is 1 H NMR (300 MHz) spectra of 3-Phenylpropyl 3-(phenyl)-2-propenoate (in CDCl 3 ).
FIG. 4 is 13 C NMR (75.4 MHz) spectra of 3-Phenylpropyl 3-(phenyl)-2-propenoate (in CDCl 3 ).
DETAILED DESCRIPTION OF THE INVENTION
Accordingly, the present invention provides a single step green process for the Preparation of Substituted Cinnamic Esters with trans-Selectivity of general formula I
wherein X 1 , X 2 , X 3 , X 4 and X 5 are the same or different from each other and each represent a group selected from hydrogen atom, alkoxy group having 1 to 3 carbon atoms, halide group, sulfide group, haloalkyl group having 1 to 3 carbon atoms, amino group, cyano group; and R is selected from a group consisting of alkyl, aryl, arylalkyl or cycloalkyl group having carbon chain from 1 to 20 with or without substitutions at the aromatic ring and the process comprising the steps of;
a) reacting cinnamaldehydes or cinnamyl alcohols of Formula II,
wherein R′ is either CHO or CH 2 OH; X 1 , X 2 , X 3 , X 4 and X 5 are the same or different from each other and each represent a group selected from hydrogen atom, alkoxy group having 1 to 3 carbon atoms, halide group, sulfide group, haloalkyl group having 1 to 3 carbon atoms, amino group, cyano group, with an oxidant, a catalyst and an alcohol, optionally along with an organic solvent under stirring at room temperature or refluxing or under microwave irradiation or ultrasound for 1 min-20 hrs,
b) filtering the reaction mixture of step (a) and collecting the filtrate,
c) filtrate obtained from step (b) is either concentrated or directly passed through a column of solid adsorbent selected from a group consisting of alumina, silica gel,
d) eluting the packed column of step (c) with solvents of different polarities to obtain the required product of general formula (I) up to 98% yield.
In another embodiment of the present invention, wherein the developed process is used for the direct oxidation of cinnamaldehydes or cinnamyl alcohols into valuable cinnamic esters of formula I.
In another embodiment of the present invention, wherein the developed process is used for the preparation of esters such as alkyl, aryl, arylalkyl, cyclo alkyl cinnamates and the like.
In another embodiment of the present invention, the substrates used are either cinnamaldehydes or cinnamyl alcohols.
In another embodiment of the present invention, wherein the product formed is stereoselective with exclusively E-selectivity.
In another embodiment of the present invention, the oxidizing agent is selected from group consisting of DDQ, chloranil, selenium dioxide and the like.
In another embodiment of the present invention, the ratio of the substrate and oxidizing agent is ranging from 1:1 to 1:5 preferably 1:2 to 1:3 depending upon substrate used.
In another embodiment of the present invention, wherein the oxidant used for carrying out the reaction is regenerated and reused for a number of times.
In another embodiment of the present invention, the catalyst is selected from a group consisting of homogeneous inorganic or organic catalysts such as hydrochloric acid, sulphuric acid, nitric acid, formic acid, acetic acid, propionic acid, oxalic acid, ionic liquid and the like or heterogeneous catalyst such as AMBERLYST® 15, AMBERLITE® IR 120, AMBERLITE® IR 400, silica gel, alumina (acidic, basic and neutral), celite, kieselguhar and K-10 montmorillonite and the like.
In yet another embodiment of the present invention, the ratio of the catalyst and oxidizing agent is ranging from 1:20 to 1:500.
In another embodiment of the present invention, the alcohol used for the reaction is selected from a group comprising aliphatic or aromatic alcohols such as methanol, ethanol, propanol, 2-propanol, n-propyl alcohol, butanol, octanol, dodecanol, cinnamyl alcohol, benzyl alcohol, phenyl propanol, phenyl butanol and the like.
In yet another embodiment of the present invention, the organic solvent selected from toluene, dichlorobenzene, xylene, dichloromethane, diphenyl ether, dioxane, ethylacetate, chloroform and others.
In another embodiment of the present invention, the process may be carried out without organic solvent depending upon the alcohol used.
In yet another embodiment of the present invention, wherein the process developed is eco-friendly as recyclable reagents, microwave and ultrasound are used for the preparation of product.
In yet another embodiment of the present invention, wherein the heterogeneous catalyst used for carrying out the reaction is recyclable and reused for a number of times preferably for 5 to 15 times, without any significant loss in the activity.
In yet another embodiment of the present invention, wherein the method is found equally workable at room temperature, refluxing temperature, in monomode and multimode microwave and ultrasound.
In another embodiment of the present invention, the reaction is carried out by stirring the reaction mixture at room temperature for 3-20 hrs preferably 5 hrs to 9 hours.
In another embodiment of the present invention, the reaction is carried out by refluxing the reaction mixture for 1-10 hrs preferably 1 hrs to 6 hours.
In yet another embodiment of the present invention, the reaction is carried out in a domestic microwave oven operated at 700 W-1500 W power level for 10 min-80 min preferably 1 min to 45 min.
In yet another embodiment of the present invention, the reaction is successfully performed in a monomode microwave organic synthesizer operated at 50 W-300 W power level with 70-250° C. for 1 min-50 min preferably 1 min-30 min.
In another embodiment of the present invention, the microwave irradiation frequency used is in the range of 900 to 3000 MHz more preferably 2450 to 2455 MHz.
In another embodiment of the present invention, wherein the temperature attained in case of the microwave is ranging from 100-250° C. preferably 110-170° C.
In yet another embodiment of the present invention, wherein the reaction is carried out under ultrasound irradiation.
In yet another embodiment of the present invention, wherein the ultrasonicator is operated at 50-90% duty for 1-6 hours, at 20 KHz-40 KHz frequency.
In yet another embodiment of the present invention, combination of reagents used is non-hazardous.
In yet another embodiment of the present invention, a process where the reaction produces yield of the products up to 98% yield depending upon the substrate.
In yet another embodiment of the present invention, wherein the process is free from side products.
In yet another embodiment of the present invention, combination of reagents used is economical.
The present invention relates to a single step Green Process for the Preparation of Substituted Cinnamic Esters with trans-Selectivity in which commercially important cinnamic esters such as octyl methoxy cinnamate (a sunscreening agent) (G. Yener, T. Incegul, N. Yener, Int. J. Pharm., 2005, 258, 203), sintenin (an anti-cancer agent) (L. H. Hu, H. B. Zou, J. X. Gong, H. B. Li, L. X. Yang, W Cheng, C. X. Zhou, H. Bai, F. Gueritte, Y. Zhau, J. Nat. Prod., 2005, 68, 342) and methyl cinnamate (a flavoring agent) (A. Steffen, Perfume and Flavor Chemicals ( Aroma Chemicals ), Vol. I & II. Allured Publishing Corporation: IL, USA, 1994)) are obtained. The reaction proceeds through direct conversion of either cinnamaldehydes or cinnamyl alcohols into cinnamic esters in the presence of an oxidant, a catalyst and an alcohol, with or without an organic solvent in either conventional conditions or microwave or ultrasound irradiations. The oxidant for this process is selected from a group consisting of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) or chloranil or SeO 2 and the like. The alcohol used for esterification is selected from a group consisting of aliphatic or aromatic alcohols such as methanol, ethanol, propanol, 2-propanol, n-propyl alcohol, butanol, octanol, dodecanol, cinnamyl alcohol, benzyl alcohol, phenyl propanol, phenyl butanol and the like. The catalyst is selected from group consisting of homogeneous inorganic or organic catalysts such as hydrochloric acid, sulphuric acid, nitric acid, formic acid, acetic acid, propionic acid, oxalic acid, ionic liquid and the like or heterogeneous catalyst such as AMBERLYST® 15, AMBERLITE® IR 120, AMBERLITE® IR 400, silica gel, alumina (acidic, basic and neutral), celite, kieselguhar and K-10 montmorillonite and the like. The process is carried out with or without an organic solvent. Organic solvent, wherever used, is selected from a group consisting toluene, dichlorobenzene, xylene, dichloromethane, diphenyl ether, dioxane, ethylacetate, chloroform and the like. The reaction time varies from 1 min to 20 hrs depending upon the nature of substrate used and the mode of reaction as stirring at room temperature or refluxing, use of monomode or multimode microwave or ultrasound. Yield varies from 51-98% depending upon the substrate, oxidant, alcohol, catalyst and solvent used.
We have already seen the successful effect of oxidation by DDQ on phenyl propanoids ((a) B. P. Joshi, A. Sharma, A. K. Sinha, Tetrahedron, 2005, 61, 3075; (b) A. K. Sinha, B. P. Joshi, R. Dogra, U.S. Pat. No. 6,566,557, 2003; (c) A. K. Sinha, B. P. Joshi, R. Dogra, U.S. Pat. No. 6,590,127, 2003) and decided to extend it our case due to benefits such as mild oxidation, recycling ability of the spent catalyst and good yields. It was also decided to initially activate DDQ by protonation from an acid. Hence, we decided to use a mild heterogeneous catalyst in the form of resin for this reaction. Initially, cinnamaldehyde was refluxed with the oxidizing agent and a homogeneous or heterogeneous catalyst, in the presence of methanol, which provided 82% yield of the product methyl cinnamate. To further increase the yield of the product various alterations in the reaction were made. After a lot of experimentation, it was found that oxidizing agent and the homogeneous or heterogeneous catalyst, with a combination of methanol and an organic solvent over a dean stark for 4-10 hrs provided optimum yield of the product up to 95-98%. After success of formation of methyl cinnamate, methyl esters were prepared with various other substituted cinnamaldehydes and the corresponding methyl esters are prepared in very good yields within 4-8 hr of refluxing of MeOH, oxidizing agent, homogeneous or heterogeneous catalyst, organic solvent and the respective cinnamaldehydes.
Moreover, various homogeneous or heterogeneous catalysts were tested and reaction occurred in all of them, though the yield varied as the examples in the next section illustrates them.
Similarly, impact of the alcohols on the esterification reaction was also examined, and as the example section would suggest, the structure of the alcohol has some influence on the end yield of the product.
The above method was also tested by stirring at room temperature. The reaction was also tested under microwave as well as ultrasound and the method was found equally effective in all the three.
The oxidizing agent in our protocol may be regenerated by the reported methods. The heterogeneous catalyst may be retrieved back by mere filtration of the product and was found to be effective for at least fifteen cycles of reuse.
In conclusion, we have invented a resin-catalyzed oxidation of substituted cinnamaldehydes or cinnamyl alcohols with DDQ in a clean and practical method for the synthesis of various bioactive cinnamates in high yield without either using strong acids or hazardous oxidizing agents. Moreover, the oxidant as well as the catalyst are recyclable and thus effectively handle waste management making the process more economical.
The following examples are given by way of illustration of the present invention and should not be construed to limit the scope of the present invention.
EXAMPLE 1
Method for the Preparation of Methyl Cinnamate from Cinnamaldehyde Using Conventional Method (At Room Temperature)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (15 mL) is taken in a round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is stirred for 20 hrs at room temperature. After completion of the reaction (observed by TLC and GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Methyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═CH 3 ) is isolated in 98% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.56 (1H, d, J=16.55 Hz), 7.34 (2H, m), 7.21 (3H, m), 6.31 (1H, d, J=16.55 Hz), 3.64 (3H, s); 13 C-NMR (CDCl 3 , 75.4 MHz) δ167.2, 144.7, 134.3, 130.2, 128.8, 128.0, 117.8, 51.5.
EXAMPLE 2
Method for the Preparation of Methyl Cinnamate from Cinnamyl Alcohol Using Conventional Method (At Room Temperature)
A homogeneous mixture containing cinnamyl alcohol (7.5 mmol), DDQ (22.5 mmol), MeOH (20 mL) is taken in a round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is stirred for 20 hrs at room temperature. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Methyl cinnamate is isolated in 86% yield whose NMR values are found matching with reported values as in example 1.
EXAMPLE 3
Method for the Preparation of Methyl Alpha Methyl Cinnamate from Cinnamaldehyde Using Conventional Method (At Room Temperature)
A homogeneous mixture containing alpha methyl cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (15 mL) is taken in a round bottom flask and catalytic amount of acidic alumina 15 (0.1 g) is added to it. The mixture is stirred for 20 hrs at room temperature. After completion of the reaction (observed by TLC and GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Methyl alpha methyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═CH 3 ) is isolated in 55% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.61 (1H, s), 7.23 (5H, m), 3.69 (3H, s), 2.05 (3H, s); 13 C-NMR (CDCl 3 , 75.4 MHz) δ168.9, 138.9, 135.8, 129.6, 128.3, 51.3, 14.0.
EXAMPLE 4
Method for the Preparation of Isopropyl Cinnamate from Cinnamaldehyde Using Conventional Method (At Room Temperature)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), Chloronil (22.5 mmol), isopropanol (10 mL) is taken in a round bottom flask and catalytic amount of silica gel (0.1 g) is added to it. The mixture is stirred for 20 hrs at room temperature. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Isopropyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 3 H 8 ) is isolated in 49% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.59 (1H, d, J=16.55 Hz), 7.41 (2H, m), 7.27 (3H, m), 6.34 (1H, d, J=16.55 Hz), 5.07 (1H, m), 1.18 (6H, d); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.4, 144.3, 134.5, 130.1, 128.6, 128.0, 118.8, 67.7, 21.9.
EXAMPLE 5
Method for the Preparation of 3-Phenylpropyl Cinnamate from Cinnamaldehyde Using Conventional Method (At Room Temperature)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (22.5 mmol), 3-phenylpropanol (10 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of Montmorillonite K10 15 (0.1 g) is added to it. The mixture is stirred for 20 hrs at room temperature. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. 3-Phenylpropyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 9 H 11 ) is isolated in 84% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.74 (1H, d), 7.43 (2H, m), 7.28 (5H, m), 7.19 (3H, m), 6.48 (2H, d), 4.22 (2H, t), 2.69 (2H, t), 1.98 (2H, t); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.7, 144.7, 141.4, 134.6, 130.6, 129.2, 128.6, 127.4, 126.5, 118.4, 63.9, 32.3, 30.5.
EXAMPLE 6
Method for the Preparation of Methyl 4-Methoxycinnamate from 4-Methoxycinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing 4-methoxycinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (15 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of AMBERLITE® IR 400 (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Methyl 4-methoxycinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═OCH 3 , X 4 ═H, X 5 ═H, R═CH 3 ) is isolated in 91% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.56 (1H, d, J=16.55 Hz), 7.37 (2H, d), 6.80 (2H, d), 6.22 (1H, d, J=16.55 Hz), 3.73 (3H, s), 3.70 (3H, s); 13 C-NMR (CDCl 3 , 75.4 MHz) δ167.7, 161.4, 144.5, 129.7, 127.1, 115.2, 114.3, 55.3, 51.5.
EXAMPLE 7
Method for the Preparation of Methyl 2,4,5-Trimethoxycinnamate from 2,4,5-Methoxycinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing 2,4,5-trimethoxycinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (15 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of AMBERLITE® IR 120 (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Methyl 2,4,5-trimethoxycinnamate (from formula I where X 1 ═OCH 3 , X 2 ═H, X 3 ═OCH 3 , X 4 ═OCH 3 , X 5 ═H, R═CH 3 ) is isolated in 84% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.91 (1H, d, J=16.10 Hz), 7.01 (1H, s), 6.50 (1H, s), 6.37 (1H, d, J=16.10 Hz), 3.93 (3H, s), 3.88 (3H, s), 3.87 (3H, s), 3.80 (3H, s); 13 C-NMR (CDCl 3 , 75.4 MHz) δ168.2, 153.9, 151.9, 143.4, 139.7, 116.6, 115.4, 112.6, 96.9, 56.5, 56.4, 56.1, 51.5.
EXAMPLE 8
Method for the Preparation of Methyl Cinnamate From Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (15 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of acetic acid (5 drops) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Methyl cinnamate is isolated in 98% yield whose NMR values are found matching with reported values as in example 1.
EXAMPLE 9
Method for the Preparation of Methyl Cinnamate from Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (15 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of neutral alumina (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Methyl cinnamate is isolated in 96% yield whose NMR values are found matching with reported values as in example 1.
EXAMPLE 10
Method for the Preparation of Ethyl Cinnamate from Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), EtOH (15 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with EtOH (10 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Ethyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 2 H 5 ) is isolated in 94% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.72 (1H, d, J=16.19 Hz), 7.43 (5H, m), 6.47 (1H, d, J=16.19 Hz), 4.28 (2H, q, J=7.09 Hz), 1.34 (3H, t, J=7.09 Hz); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.9, 144.5, 130.1, 128.8, 128.5, 127.9, 118.2, 60.4, 14.2.
EXAMPLE 11
Method for the Preparation of Butyl Cinnamate from Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), BuOH (10 mL) and toluene (15 mL) is taken in a round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Butyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 4 H 9 ) is isolated in 94% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.48 (1H, d), 7.25 (2H, m), 7.11 (3H, m), 6.23 (1H, m), 3.98 (2H, t), 1.45 (2H, m), 1.19 (2H, m), 0.74 (3H, t); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.5, 144.2, 134.4, 129.9, 127.9, 118.2, 64.0, 30.7, 19.1, 13.6.
EXAMPLE 12
Method for the Preparation of Octyl Cinnamate from Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), octanol (15 mL) and dioxane (10 mL) is taken in a round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Octyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 8 H 17 ) is isolated in 86% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.51 (1H, d), 7.46 (2H, m), 7.26 (3H, m), 6.24 (1H, d), 3.93 (2H, m), 1.43 (2H, m), 1.16 (8H, m), 0.73 (5H, m); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.5, 144.2, 134.4, 129.9, 128.6, 127.9, 118.2, 66.5, 38.8, 30.4, 28.9, 23.8, 22.9, 13.9, 10.9.
EXAMPLE 13
Method for the Preparation of Dodecyl Cinnamate from Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), SeO 2 (11.3 mmol), dodecanol (5 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of neutral alumina (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Dodecylcinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 12 H 25 ) is isolated in 87% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.51 (1H, d), 7.28 (2H, m), 7.14 (3H, m), 6.26 (1H, d), 4.02 (2H, t), 1.50 (2H, t), 1.11 (18H, m), 0.73 (3H, d); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.4, 144.2, 134.4, 129.6, 128.6, 127.9, 118.2, 64.3, 31.9, 29.7, 29.6, 29.4, 28.7, 26.0, 22.7, 14.0.
EXAMPLE 14
Method for the Preparation of 2-Methoxyethyl Cinnamate from Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), 2-methoxyethanol (25 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of basic alumina (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. 2-Methoxyethyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 3 H 7 O) is isolated in 93% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.51 (1H, d, J=16.55 Hz), 7.28 (2H, m), 7.15 (3H, m), 6.28 (1H, d, J=16.55 Hz), 4.16 (2H, t), 3.44 (2H, t), 3.18 (3H, s); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.6, 144.8, 134.3, 130.2, 128.8, 117.8, 70.4, 63.4, 58.7.
EXAMPLE 15
Method for the Preparation of 2-Hydroxyethyl Cinnamate from Cinnamaldehyde Using Conventional Method (Refluxing Under Dean Stark Apparatus)
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), ethylene glycol (10 mL) is taken in a round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. 2-Hydroxyethyl cinnamate (from formula I where X 1 ═H, X 2 ═H, X 3 ═H, X 4 ═H, X 5 ═H, R═C 2 H 5 O) is isolated in 88% yield. 1 H-NMR (CDCl 3 , 300 MHz) δ7.65 (1H, d, J=16.55 Hz), 7.42 (2H, m), 7.29 (3H, m), 6.38 (1H, d, J=16.55 Hz), 4.37 (2H, t), 3.66 (2H, t); 13 C-NMR (CDCl 3 , 75.4 MHz) δ166.4, 145.6, 134.2, 130.5, 128.9, 128.2, 117.3, 64.1, 41.8.
EXAMPLE 16
Method for the Preparation of Methyl Cinnamate from Cinnamaldehyde Using Multimode Microwave
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (10 mL) is taken in an Erlenmeyer flask (150 ml) and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is irradiated for 10 min under multimode microwave at 900 W power level. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. The yield of the methyl cinnamate is 95% whose NMR values are found matching with reported values as in example 1.
EXAMPLE 17
Method for the Preparation of Methyl Cinnamate from Cinnamaldehyde Using Monomode Microwave
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (10 mL) is taken in a 100 ml round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is irradiated for 10 min under monomode microwave at 100 W and 125° C. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. The yield of the methyl cinnamate is 98% whose NMR values are found matching with reported values as in example 1.
EXAMPLE 18
Method for the Preparation of Methyl Cinnamate from Cinnamaldehyde Using Ultrasound Irradiation
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), MeOH (15 mL) is taken in a 100 ml beaker and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is irradiated for 6 hr under ultrasonicator for sonication (pulse length 9 sec, pause after 20 min, duty 80%). After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with MeOH (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. The yield of the methyl cinnamate is 92% whose NMR values are found matching with reported values as in example 1.
THE MAIN ADVANTAGES OF THE PRESENT INVENTION
The main advantage of the present invention is “A Green Process for the Preparation of Substituted Cinnamic Esters with trans-Selectivity” in which high valued food flavorings, cosmetic and most importantly, pharmaceutically important alkyl or aryl cinnamates are obtained from cinnamaldehydes or cinnamyl alcohols.
1. A process for direct conversion of cinnamaldehydes or cinnamyl alcohols into cinnamic esters in one pot. 2. A process for the synthesis of cinnamic esters in excellent yield ranging from 51-98%. 3. A process to employ ecofriendly and non-hazardous reagents for the preparation of unsaturated carbonyl compounds. 4. A process to prepare cinnamic esters in a few hours without any side products. 5. A process which is equally applicable in monomode multimode microwave and ultrasound irradiation. 6. A process which is equally workable in both monomode and multimode microwave instruments. 7. A process in which the catalyst is economical and environment friendly. 8. A process which utilizes less or non-hazardous chemicals. 9. An environment-friendly green process is developed wherein the oxidizing agent and the heterogeneous catalyst used is regenerated and reusable. 10. An industrially viable process towards formation of high valued alkyl/aryl cinnamates wherein the catalyst used is recyclable and there is no loss in the activity even after many cycles of use. 11. An industrially viable process, which is ecofriendly by virtue of employment of non-hazardous reagents and short reaction time. 12. An industrially viable process in which products formed can be used in flavor, perfumery, pharmaceutical and cosmetic industries (as sunscreen). | The invention provides a green process for direct oxidation of a large number of substituted or unsubstituted cinnamaldehydes or cinnamyl alcohols into the corresponding alkyl or aryl cinnamates in one step. The process of the present invention is a convenient and efficient green process for the preparation of various aryl or alkyl cinnamates under conventional, microwave and ultrasound directly from cinnamaldehydes or cinnamyl alcohols in the presence of an oxidizing agent, catalyst and an alcohol, with or without an organic solvent. These esters are immensely important compounds in flavor, perfumery and pharmaceutical industries. There are several prior arts available for the preparation of cinnamic esters, but all of them suffer from deficiencies such as use of expensive reagents and catalysts, harsh reaction conditions, use of toxic chemicals and others. In contrast, the present methodology is extremely simple and involves reaction of the substrate with an oxidizing agent mixed with a homogeneous or heterogeneous catalyst and an alcohol with or without organic solvent by stirring at room temperature or refluxing or under microwave or ultrasound irradiation to get the requisite products. | 2 |
FIELD OF THE INVENTION
[0001] The present invention pertains generally to computer databases, and more specifically, to increased performance accomplished by using a traditional database system to provide persistent information storage and a main memory database to provide increased information retrieval speeds.
BACKGROUND OF THE INVENTION
[0002] Over the last twenty years the database server has become a central and critical element of business infrastructure. Businesses rely on the database to be the safe harbor for the storage and retrieval of vital information. This requirement on reliability has produced a substantial problem for the field of computer science; technology can either be reliable, or it can be fast but rarely both. The novelty of the present invention provides the reliability of traditional database systems, with the performance of a main memory database.
[0003] Prior technology surrounding the database field is a constant game of give and take; performance can be had at the expense of reliablity. However, before the novelty of the present invention is explored deeper, it is first warranted to describe the fundamental building blocks and prior technologies.
[0004] The field of database technology is as old as computers themselves. Computers can execute basic arithmetic and Boolean logic very quickly, but rely on input to do something useful. For example, instructing a computer to add one plus one produces the result of two. The speed at which the result is generated is dependant upon the speed of the electrical device doing the calculation, and the speed at which the instruction and data is received and stored. If a user manually enters the command, the time it takes to produce a result is a function of how fast the user can type and how fast the result can be read. Very quickly the speed of the electrical devices doing these calculations outpaced even the fastest typist; thus the field of database was begun. In its simplest form, a database is a repository for the storage, and retrieval of information. In the beginning these systems simply provided batch input for programs, and stored the output. Over the years the use of computing technologies expanded from missile trajectory programs, to accounting, to games. Likewise, the database has evolved from an internal function which supports the execution of programs, to a stand-alone system.
[0005] Today's database still provides the same, crucial role of storing and retrieving data, but now it is a stand alone application. Client applications connect to the database via network, or by other programmatic means, to store and retrieve data. The form of these requests most commonly takes the form of Structured Query Language (SQL). Based on the mathematical discipline of set theory, client applications can now define a set of information, and an action to apply to the set. For example, the following SQL returns the title of all patents invented by Cary Jardin:
[0006] SELECT TITLE FROM PATENT TABLE_WHERE INVENTOR =‘Cary Jardin’;
[0007] With SQL applications, users can store and retrieve information from a database in a precise, logical, and standard way. Unfortunately, like the typist inputting too slow, applications that rely on a database for storage and retrieval of information are only as fast as the database can provide the information. This is known as a bottleneck; a system or unit that hinders the performance of the entire solution. Bottlenecks never go away, they just move. First, it was the typist not being able to enter commands fast enough. For the purpose of this invention the database is the bottleneck.
SUMMARY OF THE INVENTION
[0008] The present invention disclosed and claimed herein, in one aspect thereof, comprises a method of increasing database performance by incrementally adding more compute resources. Another object of the invention is to provide a method for traditional database systems to utilize main memory database technologies.
DESCRIPTION OF THE FIGURES
[0009] [0009]FIG. 1 illustrates a block diagram of the subject system for database request handling to accomplish database acceleration in connection with the subject invention; and
[0010] [0010]FIG. 2 illustrates an overall system architecture in which the master database system is disposed in a network in front of the slave database server and a client to accomplish the database acceleration.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Constructing a master and slave database relationship between a persistent database, and a volatile system is a very difficult and novel task. It starts by configuring the master database to utilize data not stored in a native, or local format. One method of achieving this configuration is to utilize a master database system with what is known in the field as heterogeneous table support; this ability allows the master database to access information not stored in local, or native format. Another method to achieve the master and slave database relationship is to modify the master database application to accept a prefix for tables not locally or natively stored, and a method associated with the prefix to obtain the requested information from the specified location. In ANSI SQL (Structured Query Language) this would be achieved by fully specifying the name space for each table; “data source provider”. “database name”. “table name.” One such commercially available data that supports this notation and capability is Microsoft SQL Server.
[0012] Once the master server has been configured with a slave database association, all requests for information retrieval with the “foreign” prefix specified will be delegated to the slave server for processing. Additionally, all information storage requests with the “foreign” prefix specified will be delegated to the slave server for processing which is not the objective of the current patent. For this reason, the master database must be configured with a method to locally store all provided information as well as delegate the information storage to the slave system. In this way, both machines contain identical copies of the stored information with the stored master information used for reliable persistent storage, and the slave system used for high speed information retrieval. One method of achieving this configuration is to utilize what is known as “views” and “triggers” on the master database, both of which are provided by commercial database systems such as Microsoft SQL server and Oracle. A “view” is a name space abstraction for the source of requested information. For example, information being requested from a “customer” table can be re-directed to a “new-customer” table. In this way, the user request can be routed to the most appropriate or desired source. A “trigger” provides a mechanism to execute a programmatic method at the time of an information state change. For example, when a request for storing a new customer date into the system is received, the database server executes any defined “triggers” to override the default behavior of the system. Thus, instead of saving the new customer information in the customer table, the information can be save into a “pending-customer” location for future processing. In the context of the current invention, views are used to hide the existence of the slave database system, and triggers are used to store the information on the master and slave systems from a single request for information storage. This is achieved by defining a view for each desired table in the master database system. The view can be created with an unique name, or the original table can be renamed and the view can assume the original table name. In the later instance, applications written to access the master database server can utilize the facilities of the slave system without modification. Creation of a view consists of a view name, and a definition of the information contained in the view. For the purpose of this invention, the view defended to contain the slave database system information. The defined view configuration provides ability to route information retrieval requests through the master system for fulfillment to the slave system for fulfillment. Definition of a trigger on information storage requests completes the system. The definition of a trigger consists of an associated table or view, and the action to take. For the purpose of this invention, a trigger is created to be associated with a state change on the newly defined view. In this way, the defined trigger will be executed every time a request for information to be stored into the defined view. The application logic defined within the newly created trigger will store the requested information into both the master database and the slave system from a single user request.
[0013] As previously mentioned, the current invention utilizes a main memory slave system to enhance the performance of user information retrieval requests. With both the view and trigger defined on the master system, users accessing information will be utilizing the performance of the slave database system. If the slave system should loose power or loose the stored information within, the master system can manually or programmatically modify the defined view to route requests to local or native resources. In this way, the reliability of existing database systems can be used in cooperation with less reliable, enhanced performance systems such as main memory databases.
[0014] Although the preferred embodiment has been described in detail, it should be understood that various changes, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
[0015] Turning to FIG. 1, an overall flow diagram of a database acceleration A accomplished in connection with the subject system is disclosed. The basic flow commences at start block 10 , from which progress is made to block 12 at which point the database request is received by the master database system. A determination is made at decision block 14 to determine whether the request is an information retrieval request, read operation, or information storage request, write operation. This determination is suitably accomplished by analysis of database requests, or other suitable criteria as dictated by the particular acceleration application.
[0016] A write determination at decision block 14 causes progress to block 16 . At this point, the defined “trigger” application logic is invoked to duplicate the write operation to both the local, master, data storage and the remote, slave, data storage. Flow progresses back to block 14 to determine whether a subsequent request meets the above test, as noted above.
[0017] A read determination at decision block 14 causes progression to block 18 . At this point, a database request is determined to be a local request, or a remote request. A local determination at decision block 18 causes progress to block 20 . At this point the default master database behavior is invoked to retrieve the requested information.
[0018] A remote determination at decision block 18 causes progression to block 22 . At this point the database request is forwarded to the remote slave system for retrieval of the requested information.
[0019] Once completion of all relevant requests has been completed, the acceleration A is completed, and the system proceeds to stop at termination block 20 .
[0020] Turning next to FIG. 2, a database client environment in which a preferred embodiment database acceleration is provided. A client 30 connects to the database server through network, Application Programming Interface, or other means suitable for sending and receiving requests to the database server. The Master Database Server 36 receives the client requests and routes information retrieval requests directly to the slave database server through any internally supporting methods such as views and triggers 34 . Information storage requests are processed through any internally supporting methods such as views and triggers 34 and then sent to local persistent storage 38 , and sent to the slave database server 36 to maintain a replicated image of the master local storage 38 . | The present invention provides a system to allow existing database applications to delegate costly transactions to a main memory database system while maintaining persistent and coherent storage on the existing database. The system utilizes database heterogeneous transaction support to delegate desired transaction without modification of existing database application logic. Persistency is maintained on the host database by replicating state change operations onto the associated main memory system. In this way, the present invention provides the performance of a main memory database system, with the required persistency of existing database technologies. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to washing machines and more particularly an improved means for attaching a balancing ring to an automatic washer basket.
2. Description of the Prior Art
It is common practice in an automatic washer to provide a balancing ring around the top periphery of the wash basket to stabilize the basket as it rotates during the high spin mode.
The wash basket is spun with the clothes load during spin operations, and it is important that the balancing ring be securely attached to the basket so that it does not work loose during such operations. Further, the balancing ring must be capable of being securely attached to the basket regardless of manufacturing tolerances which effect the concentricity of the basket.
U.S. Pat. No. 4,433,592 discloses a balance ring which contains both a low viscosity fluid and a plurality of spherical weights to effect balancing during spin. The balancing ring and the spin basket have cooperating flanges and are secured together by means of screws through the flanges.
U.S. Pat. No. 4,388,841, discloses a universal balancing member which comprises a hollow, annular tube member which is secured to the spin basket by means of a plurality of clip members. The clip members each extend around the outer surface of the balancing tube and have an outwardly extending head portion which snaps through a cooperating hole in the upper basket periphery.
U.S. Pat. No. 4,162,621 discloses, incidentally, a balancing ring which is fixed to the upper portion of the basket and contains a granular balancing material. Although details of the construction and attachment means for the balancing ring are not disclosed, it appears that the ring is formed of a metal member which is secured to a metal spin basket, as by welding.
U.S. Pat. No. 4,044,626 discloses a hollow, two-piece balancing ring assembly for an automatic washer. The ring includes a plurality of internal baffles extending upwardly from its bottom wall and downwardly from its top wall to modify the flow of balancing liquid within the ring. The ring is attached to the upper periphery of the spin basket by means of screws.
U.S. Pat. No. 3,610,069 discloses a one-piece balancing ring which is designed to receive a solid balancing material, such as concrete. The ring is secured to the basket by means of a plurality of screws so that the ring extends interior of the basket opening.
U.S. Pat. No. 3,462,198 discloses a balancing ring which may be used in connection with an automatic washer or other rotating mechanisms. The balancing ring is secured to the outer surface of the spin basket by means of inwardly extending projections which snap-fit to the holes in the basket. At least a portion of the balance ring can be displaced radially in response to the spinning of the basket.
U.S. Pat. No. 3,334,497 discloses an automatic washer having a balance ring which is spot welded to the inner wall of the basket. The ring contains a solid ballast material, such as cement.
U.S. Pat. No. 2,836,083 discloses a balancing ring containing a thixotropic material which is secured to the outer periphery of the basket by means of brackets which are bolted to the basket.
In each of the prior art disclosures described above, the balance ring is secured to the basket either by welding, a plurality of fasteners such as screws, or other time consuming methods in which a fastener has to be lined up with a hole in the basket, some of which may be insufficient to withstand the constant vibration and the starting and stopping of the spin basket as it moves into and out of the high spin mode.
SUMMARY OF THE INVENTION
The present invention provides a novel attachment means for a balancing ring for an automatic washer. In particular, it is an object of the invention to provide attachment means which allows the ring to be affixed to the upper basket periphery without the need for screws or other fastening means which require separate manipulation at the time of installation. It is also an object of the invention to provide fastening means which permit the ring to be installed using automated assembly equipment or, alternatively, a minimum of manual labor. It is a further object of the invention to provide an attachment means which does not require rotational alignment of the ring with the wash basket.
An annular balancing ring is provided which rests on a shoulder of the wash basket and has an inverted channel in a bottom wall to receive the rim surrounding a top opening of the wash basket. The balancing ring is provided with a plurality of clips installed in the channel prior to assembly onto the basket which engage with a downwardly facing formed edge or shoulder portion of the basket forming the top opening.
The clips have outwardly projecting barbs which engage with side walls of the channel to hold the clips in the channel and right and left tangs to engage the lip forming the basket opening. The tangs press inwardly projecting against the basket lip and the tang on the radial outside of the lip has an end which catches below the formed edge on the lip to prevent the ring from disengaging from the lip.
The ring is assembled onto the basket by placing it over the basket opening with the channel aligned with the lip and pressing down. The clips are made of a resilient material and thus will automatically engage the lip and the formed edge.
The fact that the basket is coated with a hard porcelain glaze presents the primary problem that must be dealt with in developing attachment means. In particular, the porcelain presents an extremely hard surface that resists frictional gripping or engagement by a simple barb or tang. Further, it is highly undesirable that the porcelain surface be fractured, cracked, or scratched by the attachment means, since this would permit the basket to rust at that point. Thus, the shoulder defined by the folded back edge portion of the basket lip plays an important part in the invention, since it permits the lower tang on the spring clip to prevent upward movement of the ring even though the clip does not dig into or otherwise grip the hard porcelain surface itself. The tang on the opposite side of the clip does not dig into the porcelain surface, but rather provides a spring bias to retain the first tang below the shoulder.
Since the attachment means disclosed does not require holes through the basket for receiving screws, clips or other fasteners, there is no concern about tolerances of the holes, occluding the holes, or chipping the porcelain at the holes.
Internal baffles are provided within the balance ring to slightly impede the fluid within the ring but allowing some movement of the fluid. The fluid must be able to move quick enough to counter-balance the off-balance weight when the basket is accelerating to the top spin speed. When there is no off-balance weight, the balancing fluid must be prevented from moving around the balancing ring to create an off-balance. If the fluid is restrained too much, the fluid within the ring will not move fast enough in acceleration of the basket to the top spin speed. This would cause the basket to hit the cabinet and create an unstable system. It has been found that 55-65% of the balancing ring volume filled with water is the best condition. Small baffles protruding into the center of the ring retard the flow of water.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an automatic washer embodying the principles of the present invention.
FIG. 2 is a partial side sectional view through the interior of the washer showing the balancing ring.
FIG. 3 is a bottom e1evational view of the balancing ring.
FIG. 4 is an enlarged partial side sectional view of the balancing ring.
FIG. 5 is a partial sectional view of the balancing ring taken generally along the line V--V of FIG. 4.
FIG. 6 is a partial plan view of the balancing ring assembled onto the wash basket taken generally along the line VI--VI of FIG. 4.
FIG. 7 is a side elevational view of a fastening clip.
FIG. 8 is a side elevational view of the fastening clip of FIG. 7 rotated 90°.
FIG. 9 is a side elevational view of the fastening clip of FIG. 7 rotated 180°.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, there is illustrated an automatic washing machine generally at 10 having an exterior cabinet 12 with a top surface 14 and an openable lid 16 forming a portion of the top surface. A control console 18 is positioned at a rear edge 20 of the top panel 14 and has on it a plurality of controls 22 for presetting the operation of the washer to operate through a series of washing, rinsing and drying steps.
Accessible through an opening 24 covered by the lid 16 is a perforate wash basket 26 concentrically mounted within an imperforate wash tub 28. Mounted centrally within the wash basket 26 is a vertical axis agitator 30 having a lower skirt portion 32 and a plurality of radially outwardly extending vanes 34.
The wash tub assembly is carried on supporting legs 36 which are connected to a washer frame 38 interior of the cabinet 12. Springs 40 are attached between the legs 36 and a plurality of brackets 42 secured to the tub assembly. The agitator 30 is selectively rotated and wash basket 26 is selectively rotated by means of an electric motor 44 through an appropriate transmission 46.
The interior of the wash basket 26 is shown in greater detail in FIG. 2 which is a cross-sectional view of the upper portion of the wash basket 26. It is clearly seen that the wash basket 26 is mounted concentrically within the wash tub 28 and that the agitator 30 is centrally located. The wash tub 28 has an attached top ring 48 with an opening 50 therein providing access to the interior of the wash basket 26. The wash basket 26 has a substantially circular opening 52 at a top edge 53 thereof which is smaller in diameter than the internal diameter of the wash basket 26 itself in that a curled upper lip 54 is formed at the top end of the basket 26 to form the opening 52.
The curled lip portion 54 is shown in greater detail in FIG. 4 where it is seen that there is a first inwardly curved portion 56 which extends inwardly from the diameter of the wash basket 26 thereby forming an exterior shoulder 58 near a top portion of the wash basket. The slope of the curved portion 56 decreases in a direction toward the top edge 53 of the basket 26 to a transition point 60 from which point the slope increases to a vertical slope at a neck portion 64 forming the opening 52. A portion 66 of the lip wall 54 is folded back on itself, radially outwardly, the fold forming the top edge 53 of the basket and an end of the wall forming a downwardly facing formed edge or shoulder 68.
In FIGS. 2 and 4, it is seen that there is provided a balancing ring 70 which is seated on the top edge portion 53 of the wash basket surrounding the top opening 52 of the basket. The balancing ring 70 has an upper member 72 with an outer annular wall 74 and an inner annular wall 76 connected along a top edge 77 by a top wall 78. A bottom edge 80 of the outer annular wall 74 is enlarged and has an annular groove 82 formed therein and a bottom edge 84 of the inner annular wall 76 has an annular groove 86 formed therein.
The ring member 70 also has a bottom portion 88 with an outer annular wall 90 and a relatively short interior annular wall 92 connected by a curved bottom wall 94. The outer annular wall 90 has a ridge portion 96 projecting upwardly from a top edge 98 of the outer wall 90 which mates with the annular groove 82 in the outer wall 74 of the top member 72. The inner wall 92 of the bottom member 88 has an annular edge 100 projecting to mate with the annular groove 86 of the upper member inner wall 76. The top and bottom members 72, 88 are preferably formed of a molded thermoplastic material such as polypropylene and can be permanently joined together such as by spin welding the two portions so that the ridges or edges 100, 96 will be joined to the grooves 86, 82 respectively in a water-tight manner. Other fastening methods can be used including adhesives or sonic welding techniques.
The top wall 78 of the top portion 72 is formed with at least one opening 104 therethrough sealable by a plug 106 to provide access to the otherwise sealed interior of the balancing ring.
Formed in the bottom wall 94 of the bottom portion 88 of the balancing ring 70 is a downwardly opening annular channel 115 formed by two annular walls 116, 117. One wall 116 has a diameter greater than the neck portion 64 and the other wall 117 has a diameter smaller than the neck portion 64 such that the neck 64 will be received in the channel 115. A plurality of clips 118 are captured at spaced locations around the circumference of the channel 115 as best seen in FIG. 3. The clips 118 are shown in detail in FIGS. 7, 8 and 9 where it is seen that the clips comprise generally a U-shaped member having a first downwardly extending leg 120 and a spaced, second downwardly extending leg 122 connected at a bight by a connecting portion 124. A pair of barbs 126 are formed in the first leg and a second pair of barbs 128 are formed in the second leg, both sets of barbs being turned outwardly on the clip and having a sharp, pointed edge. The first leg has an inwardly projecting tang 130 and the second leg has an inwardly projecting tang 132, the tang 130 on the first leg being positioned farther from the connecting end 124 than the tang 132 on the second leg.
Molded on the interior of the upper member 72 are a plurality of reinforcing members 108 which extend partially into the interior of the ring member primarily in the areas adjacent the joinder of the top wall 78 to the outer wall 74 and inner wall 76.
Molded within the interior of the bottom portion 88 are a plurality of baffle members 110 which extend from the outer channel wall 116, along the bottom wall 94 to the outer wall 90. Additional baffles 114 are also molded on the interior of the bottom portion 88 which extend from the inner wall 92 to the inner channel wall 117. The profile of all of the baffles combined is such that the majority of the area interior of the ring is left unimpeded.
As seen in FIGS. 4 and 5, when the clip 118 is inserted into the channel 115 in the balancing ring, the barbs 126, 128 engage into the side walls of the channel to securely lock the clip 118 to the ring 70. When the ring 70 is placed onto the basket, the neck portion 64 of the basket lip is received in the channel 115 and the tangs 130, 132 engage opposite walls of the neck portion. The tang 130 on the first leg 120 engages the radially outward side of the neck wall and the tang 132 on the second leg 122 engages the radially inward side of the neck wall.
The entire wash basket is coated with a very hard and smooth porcelain glaze which prevents any gripping or frictional engagement between a fastening means and the porcelain coated wall. Further, it is highly desirable not to scratch or crack the porcelain glaze in order to avoid rusting of the underlying metal. Therefore, the tang 132 on the second leg 122 merely presses against the radially interior surface of the neck portion 64 and the tang 130 of the first wall also merely presses against the radially exterior surface of the neck portion, but the tang 130 is also positioned below the shoulder 68 formed by the folded over end of the lip such that once the tang 130 has passed below the shoulder 68 it can no longer be pulled upwardly past the shoulder. This is due to the configuration and attachment of the tang 130 wherein a bottom edge 134 is attached to the leg 120 from which it was originally formed and a top edge 136 is free and which engages the shoulder 68. Because of the continuous biasing of the tang 132 of the second leg, the free end 136 of tang 130 is effectively prevented from disengaging with the shoulder 68.
Thus, once the balancing ring 70 is pressed onto the neck portion 64 of the wash basket lip 54, it is prevented from further movement in a vertical direction. Although the ring is not restrained from rotational movement relative to the wash basket, it has been determined during experimental use of a ring embodying the principles of the present invention that any rotational movement between the two parts is minimal and if it occurs, it is only during the rapid braking of the basket after a high speed spin operation. Rotational acceleration of the basket during the beginning of a high speed spin operation is much slower than the deceleration during braking and during the slower acceleration, there is virtually no movement of the ring relative to the basket. During the spin operation itself, the basket is rotating at a constant velocity and thus there is no acceleration and thus no movement of the ring relative to the basket.
FIG. 6 shows the spacings of the baffles formed internally of the balancing ring 70. Near the right hand portion of the figure, the baffles 110, 114 formed in the bottom member 90 are illustrated. The reinforcing ribs 108 formed on the top member 72 are shown in phantom as being closely adjacent to either side of the opening 104. These rib members may act to slightly impede the fluid within the ring, but their primary function is to add structural strength to the ring.
The ring 70 can be filled with a fluid through the opening 104 to provide the balancing function for the ring. The fluid must be able to move quickly enough within the ring to counter-balance an off-balance weight when the basket is accelerating to the top spin speed. For example, if a disproportionate amount of clothing is positioned on one side of the basket, this would result in an off-balance condition. The fluid within the ring will move to an area on the opposite side of the basket, thus counteracting off-balance condition. However, the balancing fluid must be prevented from moving around the balancing ring to create an off-balance condition when there is no off-balance weight. Thus, the internal baffles are used to prevent the unobstructed movement of the liquid within the ring. It has been determined by the Applicants that 55-65% of the balancing ring volume filled with a fluid such as water provides the best operating condition.
It is thus seen that there is provided by the present invention a means for attaching the balancing ring 70 to the wash basket 26 comprising a plurality of spring clips which snap-fit and lock to both the balancing ring and the basket. By providing the basket lip with a folded back portion or equivalent portion defining a downwardly facing shoulder, a fastening means is provided which allows for a quick and efficient means to securely attach the balancing ring to the wash basket in the form of a spring clip which is retained by the ring and which snap-fits beneath the shoulder. The balancing ring can be applied very quickly by manual effort or can be quickly and effectively attached using automated machinery. Since the balancing ring is virtually permanently attached, with no parts such as threaded fasteners to loosen, periodic checks of the balancing ring are not required.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of our contributions to the art. | An attachment arrangement is provided between a rotatable wash basket and a balancing ring in an automatic clothes washer which permits the ring to be locked onto the basket upon downward movement of the ring relative to the basket. The ring has a bottom wall with a channel therein which receives the edge of the basket opening. A plurality of spring clips having inwardly facing tangs are locked into the channel. The basket opening has a downwardly facing shoulder associated therewith and one of the tangs engages the edge of the opening below the shoulder to prevent removal of the ring while the other, opposed tang provides a biasing force to prevent the tang from disengaging from the shoulder. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to the field of acoustic transducers including planar magnetic acoustic transducers and, more particularly, to the distribution of driving forces on the diaphragm of magnetic acoustic transducers, with respect to the edges of the diaphragm which are fixed to a support frame.
2. History of the Related Art
Magnetic acoustic transducers and particularly planar magnetic loudspeakers are generally popular because of their good sound reproduction characteristics. Such loudspeakers typically include a generally flat diaphragm having a pattern of one or more conductors attached which form the "voice coil" or signal current carrying conductors. The diaphragm is positioned so that the conductors are attracted and repelled by adjacent magnets as current signals pass through the conductors, thereby causing the diaphragm to oscillate and produce sound.
The sound reproduction of a typical planar magnetic transducer is sensitive to the operating characteristics of the diaphragm. A typical diaphragm includes a thin flat polymer membrane with a pattern of thin foil-like conductors on the membrane. The conductor circuit, as described and referenced throughout this application, is the pattern of one or more conductors and equivalent terms are conductor voice coil or conductor pattern. Generally elongate portions of the conductor circuit are referred to as conductor runs and equivalent terms are conductor segments or strips. To obtain optimum acoustic response, the diaphragm is held under tension. The path for the electrical conductor runs on the diaphragm is generally chosen so the current flowing through the conductor induces net forces of uniform direction perpendicular to the diaphragm surface during operation of the transducer. Typically, the conductor runs have covered substantially most of the diaphragm so that the "active area" of the diaphragm was the area of the diaphragm not bound at the frame edges, occasionally referred to as the "open area". The generated forces in all of the conductor segments or runs within what is referenced as an "active area" of the diaphragm, cause the general direction of diaphragm motion to be perpendicular to the diaphragm surface.
The sound reproduction characteristics of a planar magnetic transducer are influenced by the shape of the frame, mechanical properties of the diaphragm and conductor pattern, location of the driven area and acoustic impedance from the support frame geometry. Typically the frame shape is rectangular and of such dimensions to produce a desired low frequency resonance as well as a characteristic dispersion at higher frequencies. The mechanical properties of the diaphragm including mass, stiffness, tension and damping all influence the modal behavior and hence frequency response of the transducer. At higher frequencies, the acoustic impedance of the underlying frame will modify the resonant behavior.
Planar magnetic transducers with partially driven areas have been known having magnet circuits and conductor patterns in either a line driver or an array of parallel bars. FIG. 1 shows an acoustic diaphragm 1 and frame 2 having a line driver 3 symmetrically placed in the middle of the rectangular shaped diaphragm as taught in U.S. Pat. No. 4,924,504 to Burton. Passive mass 4 is added to the rectangular diaphragm to control undesired resonant modes. The extra mass has the effect of reducing the output sensitivity.
FIG. 2 shows a three bar array of magnets 5 symmetrically placed in the center of a rectangular frame 6 as taught in U.S. Pat. No. 4,156,801 to Whelan et al. The acoustic transducer includes a diaphragm (not shown) with substantial non-driven area and baffles are provided contacting one side of the diaphragm to control undesired resonant modes of the diaphragm. Such baffles reduced the output sensitivity. An EMIM speaker product sold by Infinity has a design similar to the U.S. Patent to Whelan et al. and uses a combination of damping and stiffening of the diaphragm to control the undesired resonant modes.
FIG. 3 shows another three bar array of magnets 8 symmetrically placed in a rectangular frame 9 with a substantial non-driven area for the diaphragm (not shown) of an acoustic transducer as taught in UK Patent 1545517 to Millward. Again some form of damping such as foam contacting the diaphragm was used to control undesired resonant modes. Such dampening, however, reduces the output sensitivity.
FIG. 4 shows an acoustic transducer 10 of U.S. Pat. No. 3,873,784 to Doschek having a rectangular magnet pattern 11 and conductor layout 12 on diaphragms 14. The magnets and circuits are parallel to a support frame 15 and have reflection symmetry with the axis 16--16 of the frame.
The magnet structures and driven conductor lengths are parallel to the edges of a rectangular frame for these known examples of prior transducers with partially driven area. In addition, the transducers have reflection symmetry about both central axes of the frame. U.S. Pat. No. 3,674,946 to Winey describes a transducer with a triangular frame shape that functions to minimize transverse resonant waves by varying a transverse distance between the frame edges, however in this case the transducer diaphragm is fully driven over the open area, and conductor driving forces are parallel to one edge of the triangular frame.
SUMMARY OF THE INVENTION
The primary object of the invention is a reduction in the number and volume of magnets required to drive an magnetic acoustic transducer by selectively exciting diaphragm modes to produce a smoothed frequency response. The arrangement of the magnet circuit and conductor pattern is in one or more substantially elongate chain sections that are angled with respect to the edges of the diaphragm support frame or are asymmetric with respect to the axis of symmetry of the frame.
Transducers of the prior art have demonstrated a need for extra damping components to control undesired diaphragm modes particularly in passive non-driven diaphragm regions, including direct contact damping and addition of mass to the passive regions of the diaphragm. It is an object of the invention to eliminate the requirement for these extra components, hence reducing the complexity and cost of the transducer.
It is a further object of the invention to increase the sound output level for a given magnet volume by eliminating such direct contact damping on the diaphragm. The arrangement of magnets and conductor patterns in the invention reduce the excitation of undesirable vibration modes that contribute to large peaks and valleys in the frequency response of the transducers.
Another object of the preferred embodiment of the transducer is to further smooth the frequency response by addition of edge damping of the diaphragm to minimize in-phase reflections from the edges of the diaphragm, and non-contact air damping of the diaphragm such as with standard acoustic cloth.
The invention describes designs that provide partial driving of the diaphragm hence reducing the number of magnet components required while maintaining similar acoustic output. For the purposes of this invention description and including the claims, the area of the diaphragm directly driven by the electromechanical forces will be identified as the "driven area", and in general this will be substantially less than the total open area of the diaphragm.
The invention relates to using relatively few magnets in comparison to known transducers, hence the diaphragm has significant non-driven area, and the intrinsic resonant behavior is predominantly set by the frame shape and tension of the diaphragm, the other factors having a smaller influence. The invention relates to selective excitation of diaphragm modes by placement of the driving forces such that coupled energy is maximized in diaphragm modes that produce a more uniform frequency response characteristic with reduced notches in the frequency response. The preferred embodiment specifically relates to rectangular frame shapes as these frame shapes have been shown to produce a frequency response that is popular and well characterized, however the invention applies to a range of frame geometries.
Unlike the prior art, the invention uses a novel method of arranging the magnet array and conductor pattern on a diaphragm such that the diaphragm modes are selectively excited and fewer magnets are required for a given acoustic output. This is accomplished by arranging the magnet array or circuit and conductor pattern to be non-parallel to the edges of the diaphragm support frame, and asymmetric with respect to the major and minor axis of the frame. These arrangements of the magnets and conductor circuit do not require the use of baffles, contact damping or a rigid diaphragm and hence are novel. The invention can be enhanced by commonly known techniques such as edge damping, fabric cloths and the like, but the fundamental response is determined by the arrangements as described herein.
A primary characteristic of acoustic transducers is the sound output level and it is desirable to maximize the sound output pressure. Hence an object of the invention is to create the conductor design in a pattern that is angled with respect to the edges of the diaphragm frame, or asymmetric relative to the axis of the inner frame edges. The magnet circuit geometry may be similar to the conductor trace pattern, but the minimum requirement is that there is sufficient magnetic field such that the conductors are driven at an angle relative to the edges of the frame, or asymmetric to the symmetry axis of the frame, such that particular vibration modes of the diaphragm are excited that produce smooth output frequency response. Hence with this minimum geometry requirement for the driving forces the magnetic circuit may be of various forms or elements including linear bar magnets or curved magnet elements positioned near one another or a single piece non rectangular shape such as could be formed by molding.
The conductor pattern is positioned such that the conductor mass within the magnetic field is maximized and efficient coupling of the current to the available magnetic field is achieved. Hence the preferred embodiments can tolerate small gaps between magnets but do not have large sections or gaps with undriven conductor traces. There is a preferred maximum gap between ends of the elongate magnets beyond which efficiency of the transducer decreases substantially. An additional benefit of the elongate magnetic circuits of the invention is that the transducer is efficient using one integral circuit pattern on the diaphragm, that extends along a predetermined selective driving portion thereof. Additional circuit patterns may be added to the diaphragm to produce independent driving areas, however there is a resulting tradeoff in complexity of electrical connections and more non-driven conductor mass on the diaphragm.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an assembly view of a prior art design of a line driver geometry in a rectangular frame;
FIG. 2 is a top plan view of a prior art diaphragm pattern showing a parallel array of conductor traces covering only the middle region of the diaphragm and parallel and symmetric to the edges thereof;
FIG. 3 is a top plan view of another prior art frame configuration showing placement of three parallel bar magnets covering only the middle region of the diaphragm and parallel and symmetric to the edges of the diaphragm support frame;
FIG. 4 is a perspective view having portions broken away of a planar magnetic transducer with a rectangular magnet and conductor pattern centered in the middle region of each diaphragm and parallel and symmetric with the edges of the diaphragm support frames;
FIG. 5 is a top perspective assembly view of a magnet chain line driver showing both conductor and magnet patterns relative to the transducer frame and diaphragm in accordance with the present invention;
FIG. 6 is a top perspective assembly view of a modification of the straight magnet chain array of FIG. 5 showing a different asymmetric orientation of the chain array with respect to the frame;
FIG. 7 is a top perspective assembly view of a chain array similar to FIG. 6 including three magnets oriented asymmetrically with respect to the diaphragm support frame and symmetrical axes of the frame with the magnets oriented in a zigzag configuration;
FIG. 8 is a top perspective assembly view of a magnet chain array showing three arcuate magnets extending asymmetrically with respect to the surrounding frame;
FIG. 9 is a top perspective assembly view of a linear chain driver pattern with three branches and angled and asymmetric to the frame edges;
FIG. 10 is a top perspective assembly view of a linear chain driver pattern with two elongate magnet chains
FIG. 11 is a top perspective assembly view of a linear chain driver pattern with three elongate magnet chains of varying length;
FIG. 12 is a top view of a linear chain driver pattern with elongate magnet chains arranged as a rectangular shape with all magnets angled non-parallel with respect to the edges of the frame;
FIG. 13 is a top view of a linear chain driver pattern with elongate magnet chains arranged as a star shape with all chains angled non-parallel with respect to the edges of the frame;
FIG. 14 is an enlarged illustrational view of the linear chain driver pattern of FIG. 7 showing the maximum optimum gap between magnet chains or magnets in a chain array; and
FIG. 15 is an enlarged partial cross-sectional view showing the relationship between the conductor patterns and magnet arrays of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment relates to various arrays of the magnet placement and conductor patterns on diaphragms used with acoustic transducers. In the prior art, as the magnet coverage relative to the diaphragm is decreased, the magnets and conductors are maintained parallel and symmetric to the edges of the diaphragm support frames thus creating, undesirable notches and resonances in the frequency response of the transducers, requiring damping of the diaphragms. The damping of the diaphragms may result in a reduction in transducer sensitivity and also requires extra components and complexity.
It has been determined that the arrangement of magnets and conductors should be angled to the edges of the frame and asymmetric with respect to the symmetrical central axes of the frame in order to selectively excite diaphragm modes to reduce the coupling of modes that cause substantial notches in the audible region.
Each of the embodiments in the present invention will be disclosed as incorporating a transducer frame 20 defined by raised opposite end walls or edges 21 and 22 and sidewalls or edges 23 and 24. The raised edges are interconnected by a backing plate 25 having a plurality of spaced openings 26 therethrough through which sound waves are transmitted. As opposed to spaced openings, open channels may be formed in the backing plate for purposes of allowing passage of sound waves which are created by vibration of a diaphragm 28 which is secured to the side edges of the diaphragm so as to be spaced from one or more magnets which are mounted to the backing plate. The magnets are utilized to interact with an electrical circuit which is associated with the diaphragm in a manner which will be discussed in greater detail hereinafter.
The diaphragm is formed of a thin flexible polymer material, such as Mylar™ or Kapton™ approximately 1 mil thick, however other materials known in the art such as paper or fabric may be substituted with similar results. In particular materials with increased internal damping are suited.
The diaphragm support frame is preferrably ferrous to improve the magnetic circuit capability of the transducer assembly. As opposed to mounting the diaphragm directly to the frame 20, in some embodiments, although not shown in the drawings, the diaphragm may be mounted to an intermediate frame which is mounted between a pair of opposing frames such as shown at 20. It should be noted that in most embodiments, each frame 20 will be associated with an opposing frame 20 having magnets applied thereto which are supported in an array which is a mirror image of the arrays which will be described in the embodiments disclosed herein.
In the preferred embodiments, the magnets are carried by the backing plates 25 and the support frames are positioned on opposite sides of the electrical conductor traces or segments which are carried by the diaphragm with like poles of the magnets being in opposing relationship with respect to one another. In this respect, FIG. 15 is an enlarged cross-sectional view showing a diaphragm 28 having an electrical circuit pattern 29 applied thereto and wherein magnets 27 are mounted to the backing plates 25 associated with a pair of opposing frames 20. Like poles of the magnets are shown as being in opposing relationship with respect to one another on opposite sides of the diaphragm. When electrical current is supplied to the electrical circuit 29, the magnetic field created by the opposing magnets will cause a pulsation or push pull effect on the diaphragm thereby generating vibrations creating the sound waves which will be transmitted from the space between the frames and through the openings 26 in the backing plates. The field of magnetic flux is illustrated by the lines shown in the enlarged cross section. It should be noted that other arrangements of the magnets, either on one or both sides of the diaphragm, may be utilized in accordance with the teachings of the present invention. Further, the diaphragm may be mounted to an intermediate frame which is clamped and held between the frames shown at 20 in FIG. 15. However, for purposes of the description of the preferred embodiments disclosed herein, only a single frame will be described.
With particular reference to FIG. 5, a first embodiment of the present invention is disclosed. In this embodiment, a linear chain of magnets 30 is shown including permanent bar magnets 31, 32, and 33 which are aligned generally in end-to-end relationship along the backing plate 25 of the frame 20. The magnets comprising the linear chain create a line driver having a common elongated axis 34 which is angled with respect to the side edges of the frame or asymmetrical, that is, without reflection symmetry with respect to the side edges of the frame.
The frame 20 includes a symmetrical elongated central axis "A--A" and a smaller central transverse axis "B--B" each of which intersect the sidewalls of the frame at a 90° angle. The array of magnets 30 are shown as being asymmetrical not only with respect to the sidewalls of the frame but also with respect to the symmetrical axes "A--A" and "B--B" of the frame. Also as shown in FIG. 5, the diaphragm 28 is provided with an electrical circuit pattern 35 which is configured so as to generally outline the chain of magnets 30 and includes an input contact 36 and output contact 37 which are connected to appropriate electrical contacts (not shown) which will be provided on one of the frames 20 which support the diaphragm therebetween. The general offset alignment of the electrical circuit pattern 35 is shown in FIG. 15 such that the circuit generally follows the outline of the magnetic chain 30 and on either side thereof between the input 36 and output 37. In this manner, the electrical circuit extends through the field of magnetic flux created between the north and south poles of the magnets as is illustrated in FIG. 15.
The arrangement of the linear magnet chain array 30 and the electrical trace pattern 35 is such as to reduce undesirable vibration modes in the diaphragm which, in conventional acoustic transducer, contributes to large peaks and valleys in a frequency response. It has been determined that by minimizing, to a great a degree as possible, the actual driven active surface area of the diaphragm, i.e. that area to which the electrical trace pattern is applied, and by arranging the magnet array such as to be asymmetric to the edges of the frame and to the symmetrical axes thereof, a smoother output frequency response is obtained. Further, with the present invention, the mass created by the conductor pattern associated with the diaphragm is efficiently oriented within the magnetic field created by the chain of magnets 30. Therefore, unlike many prior art acoustic transducers, there is no conductor mass provided which is spaced inefficiently relative to the magnetic field created by the magnets which would adversely effect the frequency response of the diaphragm during use.
Although three planar permanent bar magnets are shown in the chain array of FIG. 5, it should be noted that two or more magnets will be normally used in the chain arrays of the present invention. Further, as described herein, a chain array refers to magnets placed in end-to-end relationship or end to side relationship. Where multiple chains are used, the magnets of different chains are preferably spaced at a gap distance "g", as shown in FIG. 14. Generally, the optimum gap distance is equal to generally not greater than twice the effective width "w" of the bar magnets. Such a gap distance will optimize the magnetic force which drive the conductors on the diaphragm and will prevent magnetic interference between the magnets of the chain arrays. The magnet chains may be open geometric arrays, as shown in FIGS. 11 or 13, or closed polygon arrays such as shown in FIG. 12.
With reference to FIG. 6, a variation of the first embodiment of the present invention is disclosed. In this variation, a linear magnet chain is shown as a single elongated magnet 40. The magnet extends along a diagonal line relative to the frame. The magnet 40 includes an elongated axis 41 which is angled or asymmetric with respect to the edges of the frame 20.
As with the embodiment of FIG. 5, the diaphragm 28 is provided with an electrical circuit pattern 45 configured to follow the general outline of the magnet 40. The electrical pattern includes an electrical input contact 46 and an output contact 47. The magnet 40 is shown as being angled relative to or asymmetrical with respect to the symmetrical axes of the frame 20.
With specific reference to FIG. 7, another variation of the embodiment disclosed in FIG. 5 is disclosed. In this embodiment, the elements in common with the embodiment shown in FIG. 5 have the same number. A magnet pattern or chain array 50 is shown as including three magnets 51, 52, and 53 which are arranged in a geometric open pattern wherein an elongated axis of each of the magnets, such as shown at 54--54 for magnet 53, is oriented asymmetrically with respect to the sidewalls or edges of the frame 20 and also asymmetrical or not parallel with respect to the primary longitudinal axis "A--A" and the minor axis "B--B" of the diaphragm 28. As with the previous embodiments, the electrical circuit pattern 55 is shown as including an input 56 and output 57 with the configuration of the pattern following the open geometric configuration defined by the magnet array 50. Again, the circuit pattern includes circuit segments which extend along the outer edges of each of the magnets in a manner as generally defined by the cross sectional view shown in FIG. 15 so as to be within the magnetic field of the magnets. As with the previous embodiments, the same smoothing of the frequency response is obtained by the asymmetrical relationship of the drive magnets and the electrical circuit pattern applied to the diaphragm with respect to the frame 20. Further, the mass created by the electrical circuit on the diaphragm is confined to the actively driven portion of the diaphragm overlying the magnet chain array 50.
With specific reference to FIG. 8, another embodiment of the invention is disclosed. In this embodiment, the chain array of magnets 60 is somewhat linear but the magnets are formed or molded so as to be arcuate in configuration. The magnets 61, 62 and 63 are shown as being oriented in end-to-end relationship about an axis 64--64 which is angled relative to or asymmetrical and not parallel to the elongated edges or sidewalls 23 and 24 of the frame 20 or to the edges or end walls 21 and 22 of the frame and are further asymmetrical with respect to the symmetrical axes "A--A" and "B--B" of the frame. The electrical conductor pattern 65 extends from an input 66 to an output 67 in a curvilinear configuration which generally outlines the magnet array 60 in a manner as previously described. The electrical conductor segments or pattern 65 is also asymmetrical with respect to the elongated axis of the frame in a manner similarly described with respect to the previous embodiments. The arrangement of the magnetic pattern and the electrical circuit of this embodiment provides a similar smooth frequency response as discussed above with respect to the previous embodiments.
FIG. 9 of the drawings shows another embodiment of the invention which incorporates a magnet chain array in an open geometric configuration. In this embodiment the array 70 includes magnets 71, 72, and 73 which are mounted to the back plate 25. Each of the magnets is of a different length with the longest magnet being shown at 71 and the shortest at 73. The magnets are spaced in end-to-end relationship with respect to one another by a predetermined gap distance. The diaphragm 28 includes an electrical circuit pattern 74 which is of a configuration to outline the three magnets creating the open geometric magnetic pattern 70 in a manner as previously described and extend from an input 75 to an output 76. It should be noted that each of the branches formed by the elongated axes of the magnets 71, 72 and 73 such as exemplified by the axis 77--77 of magnet 71, is oriented non-parallel and thus asymmetrically with respect to the edges of the frame as well as with respect to the symmetrical elongated and short axes "A--A" and "B--B" thereof. The open geometric configuration provides smooth frequency response as described with respect to the previous embodiments.
Another embodiment of the present invention is shown in FIG. 10 as including a short and long chain open geometric configuration of magnets 80 which include a linear chain 81 including magnets 82, 83, and 84 which are aligned somewhat similarly to the embodiment of the invention shown in FIG. 5. In this embodiment, however, a second short chain is formed by a single elongated magnet 85 which extends at an angle from the base of the main magnet chain 81. As with the previous embodiments, the elongated axis defined by any of the magnets, such as shown by the axes 86--86 of magnet 85, is angled and asymmetrical with respect to the side edges of the frame 20 and further asymmetrical with respect to the elongated symmetrical axes "A--A" and "B--B" of the frame. In this embodiment, the electrical circuit 87 is shown as being a somewhat "v" configuration and is designed to extend around the periphery of the elongated magnets of the chain array 80 from an input 88 to an output 89 formed on the diaphragm 28.
In FIG. 11, another embodiment of the present invention is shown including a magnet chain array 90 mounted to the backing plate 25 of the frame 20. The chain array is an open geometrical pattern including three branches defined by elongated magnets 93 and 94 which extend from a linear chain of magnets 91 and 92. The elongated axis of each of the magnets, such as exemplified by the axis 95--95 of the elongated magnet 93, are non-parallel and asymmetrical with respect to the edges of the frame and also with respect to the axes "A--A" and "B--B" of the frame. Also, the diaphragm 28 includes an electrical circuit 96 applied thereto which follows the outline of the magnet array 90 so as to be within the magnetic field of the magnets. The circuit extends from an input 97 to an output 98. As with the previous embodiments, the asymmetrical orientation of the magnets and electrical circuit as well as the concentration of mass of the electrical circuit relative to the magnets results in a smoother frequency response of the diaphragm when the transducer is use.
Another embodiment of the present invention is disclosed in FIG. 12. In this embodiment the chain array of magnets 100 secured to the backing plate 25 of the frame 20 follow a generally rectangular configuration although the magnets need not be parallel along each of the opposing edges of the chain array. As shown in the drawing, the array includes two shorter end magnets 101 and 102 which are generally not parallel with respect to one another and which are also not parallel to the edges of the frame 20 nor to the symmetrical axes "A--A" and "B--B" of the frame. The array further includes elongated magnets 103 and 104 which are also slightly offset so as not to be parallel with respect to one another and are also not parallel or symmetrical to the edges of the frame or the symmetrical axes thereof. The diaphragm 28 includes an electrical circuit 105 which extends from an input 106 to an output 107 which follows the arrangement of the magnets forming the array 100 when the diaphragm 28 is attached to the frame 20. It should be noted that the magnet chains forming geometric configurations may be mounted to the backing plate in substantially any polygonal arrangement.
A further geometric variation of the present invention is disclosed in FIG. 13. In this embodiment, the magnets are applied to the backing plate 25 as a star shaped array or pattern 110 including a pair of spaced elongated magnets 111 and 112 which are generally aligned axially with respect to one another. The array includes a second pair of magnets 113 and 114 which are also aligned axially with respect to one another and a third pair of shorter magnets 115 and 116 which are not shown as not aligned axially with respect to one another but which may be. In this embodiment, the elongated axes of the magnets 111-116 are not symmetrical or parallel to the edges of the frame or to the symmetrical axes defining the frame at "A--A" and "B--B". The embodiment further includes an electrical circuit pattern 117 which extends from an input 118 to an output 119 which is applied to the diaphragm 28 outlining the magnetic array 110.
As with the previous embodiments, although the mass associated with the circuit of the embodiments of FIGS. 12 and 13 is greater than that of the other embodiments, a benefit is obtained over conventional prior art transducers by concentrating the mass relative to the asymmetrical configuration of the permanent magnets secured to the backing plate 25 of the support frame such that an improved frequency response is obtained.
In view of the foregoing, the present invention discloses an asymmetrical arrangement for magnets associated with acoustic transducers and for providing electrical circuits on the diaphragms of the transducers which are formed so that the mass thereof is directly aligned with the magnetic fields created by the magnet chains of the transducer. Further, it is possible to incorporate the curved features of the magnets shown in FIG. 8 in other embodiments as disclosed and variations thereof.
Although the drawings have been described utilizing a frame which is rectangular in configuration, the teachings of the present invention may be utilized with substantially any polygon frame defining an opening therein for supporting a flexible diaphragm and wherein the orientation of the array of magnets is such that the elongated axis of any one of the magnets of the array is asymmetrical or non-parallel with respect to the side edges defining the polygon configuration. Therefore, the frame may have three or more side edges associated therewith. | An acoustic transducer with partially driven area of the diaphragm such that the driving forces are asymmetric with respect to the frame axis of symmetry or angled with respect to edges of diaphragm support frame to provide uniform frequency response of the transducer. The elongate magnet sections surround portions of the diaphragm with a fringing magnetic field within which a circuit of conductor strips is positioned such that selectively excited vibration modes of the diaphragm provide a smooth frequency response. | 7 |
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
The present invention relates to composite hollow cylindrical structures, more particularly to composite hollow cylindrical structures which are rib-stiffened and to filament winding methods for fabrication thereof.
Filament winding is a technique which is known in the art for the manufacture of cylindrical structures (e.g., tubes and pipes), spherical structures, and other surfaces of revolution. Typically, the filament winding process involves utilization of a resin bath through which dry fibers are passed and then wound; this type of filament winding is known as "wet winding." In this technique the wind angle, band width and two tension are controlled. Incorporated herein by reference is an informative text on fiber composites: Agarwal, Bhagwan D., and Broutman, Lawrence J., Analysis and Performance of Fiber Composites, 2nd Ed., John Wiley & Sons, Inc., New York, 1990; see, especially, section 2.3.1.3 "Filament Winding," pp. 42-44.
Filament winding has been used by the United States Navy for various applications. For example, a wet winding procedure has been utilized by the U. S. Navy for the Advanced Unmanned Search System Vehicle (AUSS). The U.S. Navy has also utilized a wet winding procedure in the filament winding process for the manufacturing of the Composite Propeller Drive Shaft.
Manufacture of various types of composite structures having ribs or stiffeners is known in the art. In the manufacturing process for rib-stiffened flat structures, what is generally involved is the separate manufacture of the ribs and of the face sheets, followed by secondary bonding.
A rib-stiffened configuration has also been considered for cylindrical applications. A typical approach for achieving a rib-stiffened cylindrical design involves first winding ribs onto a mandrel which has rib grooves machined in it. After the ribs are wound or fabricated, the rest of the cylindrical form is wound. The mandrel, which is typically sectional, is then disassembled and the cylinder is removed. With this type of design, however, internal connections are made either to the ribs or the skin itself; hence, there is a direct path for vibration energy to propagate from the interior to the exterior of the structural form. This approach is thus deficient for applications in which maximization of energy dissipation from the inside to the outside of the cylinder is desired.
A process used in the filament winding of rib-stiffened cylinders which is similar to the one described above for flat shape applications is disclosed in a publication, incorporated herein by reference, from a 1986 Society of Manufacturing Engineers proceeding. See Harruff, P., Tsuchiyama T., and Spicola, F. C., "Filament Wound Torpedo Hull Structures," Fabricating Composites '86 Proceedings, Society of Manufacturing Engineers, Sep. 8-11, 1986, Baltimore, Md. This process requires the fabrication and curing of the skin and stiffeners, followed by the machining of the cylinder inner diameter and the rib outer diameter to high tolerance. After this is done, the ribs are carefully positioned and adhesively bonded to the skin. The materials used for the application disclosed by Harruff et al., it is noted, are a prepreg tape for the cylinder wall and a wet winding system for the ribs.
As aforementioned herein, wet winding procedures have been used by the U.S. Navy for the Advanced Unmanned Search System Vehicle (AUSS) and the Composite Propeller Drive Shaft. The AUSS was a cylinder of constant thickness and no ribs. See Technical Report 1245, August 1988, Stachiw, J. D., and Frame, B., "Graphite-Fiber-Reinforced Plastic Pressure Hull Mod 2 for the Advanced Unmanned Search System Vehicle," Naval Ocean Systems Center, San Diego, Calif., incorporated herein by reference; see therein, especially, pages 16-21, and FIG. 18 on page 54 therein ("Schematic of Winding Operation"). For the manufacture of the Composite Propeller Drive Shaft, dry tows are passed through a resin bath to coat the tows. After tow impregnation they are fed onto the mandrel at various orientations to achieve the desired part. Incorporated herein by reference is Report No. DTRC-PASD-CR-1-88, Contract No. N00167-86-C-0150, Tulpinsky, Joseph F., and May, Marvin C., "Filament Winding Process for Composite Propeller Drive Shaft Sections," October 1986 to October 1987, prepared by Hercules, Inc. for David Taylor Naval Ship R & D Center; see, especially, pages 4-1 through 4-8 therein (Chapter 4.0 "Manufacturing").
The U.S. Air Force used the filament winding technique for the B-1B composite Rotary Launch Tube. Here the winding process utilized prepreg tape in favor of the wet winding technique in order to achieve a tighter control on fabricated properties. Incorporated herein by reference is Peters, S. T., Humphrey, W. D., and Foral, R. F., Filament Winding, Composite Structure Fabrication, Society for the Advancement of Material and Process Engineering, Covina, Calif., 1991; see, especially, pages 2-9, 2-12, 11-1 to 11-3.
Although the above-described processes for manufacturing bodies of revolution have achieved satisfactory results, they have generally been discontinuous and time-consuming and have required precision equipment and machining.
OBJECTS OF THE INVENTION
In view of the foregoing, it is a principal object of the present invention to provide an improved rib-stiffened hollow cylinder construction and fabrication methodology.
It is a further object of the present invention to provide an improved hollow cylinder construction and fabrication methodology for use as a mechanical vibrational energy-dissipating enclosure.
Another object of this invention is to provide an improved hollow cylinder construction and fabrication methodology for use as a directionally controllable thermal energy-transmitting enclosure.
A further object of this invention is to provide an improved hollow cylinder construction and fabrication methodology which admits of a continuous fabrication procedure.
Another object of the present invention is to provide an improved hollow cylinder construction and fabrication methodology which would be advantageously suitable for such applications as, e.g., chemical or petro-chemical storage tanks, manned or unmanned submersible pressure hulls, manned or unmanned aircraft, and manned or unmanned spacecraft.
SUMMARY OF THE INVENTION
The present invention provides a multiple composite translated rib-stiffened cylinder with hollow core which may be fabricated in an unbroken procedure and is suitably used as a mechanical vibrational energy dissipating enclosure. The multi-cored, rib-stiffened cylindrical design according to this invention is capable not only of dissipating internal mechanical vibrational energy but also of minimizing the energy transmitted to the external environment.
This invention provides a method, using a cylindrical mandrel, for fabricating a translated double rib-stiffened composite cylinder having a hollow core. "Circumferential" winding, as used herein, means in a direction or directions of selected filment orientation or orientations about the circumference of the cylinder. "Longitudinal" winding, as used herein, means in the axial or generally axial direction of the cylinder. This method provided by the present invention comprises: Winding circumferentially an inner skin around the cylindrical mandrel; winding circumferentially a plurality of inner circumferential ribs around the inner skin, the inner circumferential ribs spaced apart longitudinally; positioning a pair of inner pin rings at the axial ends of the cylindrical mandrel, one inner pin ring at each axial end, each inner pin ring having a ring portion and a plurality of pins spaced apart circumferentially and projecting radially from the ring portion; winding longitudinally a plurality of inner longitudinal stringers, the inner longitudinal stringers transversely superposed on and contiguous with the inner circumferential ribs, the inner longitudinal stringers engaged with the pins of the inner pin ring and spaced apart circumferentially and correspondingly with the pins of the inner pin ring; winding circumferentially a pair of inner bands, the inner bands located longitudinally inward of and adjacent to the first pin rings; winding circumferentially an intermediate skin around the inner bands and the inner longitudinal stringers; winding circumferentially a plurality of outer circumferential ribs around the intermediate skin, the outer circumferential ribs spaced apart longitudinally and staggeringly with respect to the inner circumferential ribs; positioning a pair of outer pin rings at the axial ends of the cylindrical mandrel, one outer pin ring at each axial end, each outer pin ring having a ring portion and a plurality of pins spaced apart circumferentially and projecting radially from the ring portion; winding longitudinally a plurality of outer longitudinal stringers, the outer longitudinal stringers transversely superposed on and contiguous with the outer circumferential ribs, the outer longitudinal stringers engaged with the pins of the outer pin ring and spaced apart circumferentially and correspondingly with the pins of said outer pin ring; winding circumferentially a pair of outer bands, the outer bands located longitudinally inward of and adjacent to the outer pin rings; and winding circumferentially an outer skin around the outer bands and the outer axial stringers.
In fact, this invention provides a method, using a cylindrical mandrel, for fabricating a translated rib-stiffened composite cylinder having a hollow core which is multiple-layered. The cylinder can be double-layered, triple-layered, quadruple-layered, quintuple-layered, sextuple-layered, septuple-layered, or layered in any greater multiple. This method comprises: (a) winding circumferentially an inner skin around the cylindrical mandrel, this step (a) forming the inner layer of the composite cylinder; (b) winding circumferentially a plurality of first circumferential ribs around the inner skin, the first circumferential ribs spaced apart longitudinally; (c) positioning a pair of first pin rings at the axial ends of the cylindrical mandrel, one first pin ring at each axial end, each first pin ring having a ring portion and a plurality of pins spaced apart circumferentially and projecting radially from the ring portion; (d) winding longitudinally a plurality of first longitudinal stringers, the first longitudinal stringers transversely superposed on and contiguous with the first circumferential ribs, the first longitudinal stringers engaged with the pins of the first pin ring and spaced apart circumferentially and correspondingly with the pins of the first pin ring; (e) winding circumferentially a pair of first bands, the first bands located longitudinally inward of and adjacent to the first pin rings; (f) winding circumferentially a first outer skin around the first bands and the first axial stringers, these steps (b) to (f) inclusive forming the first outer layer of the composite cylinder, the first outer layer including the first circumferential ribs, the first pin rings, the first longitudinal stringers, the first bands, and the first outer skin; (g) winding circumferentially a plurality of second circumferential ribs around the second skin, the second circumferential ribs spaced apart longitudinally and staggeringly with respect to the first circumferential ribs; (h) positioning a pair of second pin rings at the axial ends of the cylindrical mandrel, one second pin ring at each axial end, each second pin ring having a ring portion and a plurality of pins spaced apart circumferentially and projecting radially from the ring portion; (i) winding longitudinally a plurality of second longitudinal stringers, the second longitudinal stringers transversely superposed on and contiguous with the second circumferential ribs, the second longitudinal stringers engaged with the pins of the second pin ring and spaced apart circumferentially and correspondingly with the pins of the second pin ring; (j) winding circumferentially a pair of second bands, the second bands located longitudinally inward of and adjacent to the second pin rings; (k) winding circumferentially a second outer skin around the second bands and the second longitudinal stringers, these steps (g) to (k) inclusive forming the second outer layer of the composite cylinder, the second outer layer including the second circumferential ribs, the second pin rings, the second longitudinal stringers, the second bands, and the second outer skin; and (1) repeating steps (g) to (k) inclusive any number of times, each repetition of steps (g) to (k) inclusive forming a next outer layer of the composite cylinder, each next outer layer being radially outward of the previous outer layer, the previous outer layer being the radially outermost outer layer prior to the repetition of steps (g) to (k) inclusive, the previous outer layer including the previous circumferential ribs, the previous pin rings, the previous longitudinal stringers, the previous bands, and the previous outer skin, the next outer layer including next circumferential ribs, next pin rings, next longitudinal stringers, next bands, and a next outer skin, the next circumferential ribs spaced apart longitudinally and staggeringly with respect to previous circumferential ribs.
The present invention also provides a multiple-layered, translated rib-stiffened composite cylinder having a hollow core, the composite cylinder being produced by the above-said method for fabricating a translated rib-stiffened composite cylinder having a hollow core which is multiple-layered. The composite cylinder comprises: An inner layer which includes an inner skin; and at least one outer layer, each said outer layer including a plurality of circumferential ribs, a pair of pin rings, a plurality of longitudinal stringers, a pair of bands, and an outer skin.
The multiple-rib cylinder assembly of the present invention, featuring a multiple-layer rib-stiffener configuration, advantageously minimizes the vibrational energy transmitted to the environment from internal vibrating structures. The multiple stiffener design achieves maximum dissipation of vibrational energy from the inside of the cylinder to the outside. Any vibrational energy that is incident at the inner surface is not directly connected to the outer skin. For example, in the case of the double stiffener design of this invention, the vibrational energy is initially passed through to the middle skin at the rib-stiffeners, which in effect is a reduced energy source. After this energy is passed onto the middle skin, it again can only pass onto the outer skin by traveling through the rib-stiffeners. Once it is passed through these rib-stiffeners, the outer skin is excited. There is dissipation in the energy that is transmitted to the outer skin for three reasons. Firstly, there is no direct connection between the source and the outer skin. Secondly, because of the vibration damping of the composite, and the fact that energy is dissipated over a distance, the larger the distance that the vibration travels, the lower the magnitude of the vibration. In this manner, the energy that is finally transmitted to the outer skin is significantly less, which will result in a quieter (and, as the case may be, stealthier) structure. Thirdly, because of the path that the internal vibrational motion must follow, there may be a tendency for conversion of interior longitudinal vibrational motion, which is difficult to dissipate to flexural vibrational motion, which is dissipated rather efficiently by composite materials.
Moreover, the multi-layered, rib-stiffened composite cylinder assembly of the present invention provides for easier thermal management through the use of metallic inner skin with all other parts being composite; alternatively, composite materials such as graphite fibers in an epoxy could also be used for the inner skin for thermal management concerns. In this manner, the heat in the interior of the cylinder can be transmitted to a specific location on the cylinder or can be dissipated to appear to be of other shape than it actually is. This results because the composite is insulating in directions normal to the fiber direction and will not transmit the heat through it. All (or virtually all) of the heat can be made to exit at specific location(s).
Additionally, the present invention features a material winding fabrication methodology which admits of continuous winding and layering. This invention thus provides an efficient fabrication method for making composite cylindrical sections in a continuous process.
It should also be emphasized that the multiple wall construction of the present invention provides a damage-tolerant design. A notable feature of this invention is the multiplicity of layers having rib-stiffeners which are translatedly disposed in relation to the rib-stiffeners of each adjacent layer. The outer skin provides protection to the interior skins from shock or foreign object impact because direct structural connection is minimized; hence, significant catastrophic damage to the rest of the structure is minimized.
Other objects, advantages and features of this invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the present invention may be clearly understood, it will now be described, by way of example, with reference to the accompanying drawings, wherein like numbers indicate the same or similar components, and wherein:
FIG. 1 through FIG. 8 are schematic perspective views representing the steps of the fabrication methodology of the present invention.
FIG. 9 is a diagrammatic axially transverse sectional view of the double-ribbed composite cylinder of this invention, taken along the plane of line 9--9 in FIG. 8.
FIG. 10 is a diagrammatic partial perspective detail view of the mandrel and pin ring shown in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Cylindrical workpiece 18, shown in various stages of completion in FIG. 1 through FIG. 8, is outward of and coaxial with mandrel 20. Referring now to FIG. 1, inner skin 22 is made of fibrous material. Unidirectional fibers are wound around cylindrical mandrel 20 to form a continuous skin, inner skin 22. Inner skin 22 of cylinder workpiece 18 has an outer surface defining a cylindrical shape which is coaxial with mandrel 20.
As the term is used herein, a "fibrous" material is fiber, filament or tape of any appropriate material composition. In the context of circumferential winding, for most embodiments of the present invention the fibrous material has a width less than length 1 of completed cylinder 18, shown in FIG. 8; however, for some embodiments, the fibrous material which is circumferentially wound to form inner skin 22 or a subsequent continuous skin is a sheet-like material having a width commensurate with the longitudinal expanse of mandrel 20 and approximately equal to length 1 of completed cylinder workpiece 18. In the context of longitudinal winding, the width of the material being wound is generally normal to the longitudinal expanse of mandrel 20 as well as to the longitudinal expanse of the cylinder workpiece 18; here, a fibrous material has a width less than the circumference of the cylindrical shape along which the fibrous material is being wound. Hence, when the fibrous material is engaged with inner pins 30 and longitudinally would along the cylindrical shape defined by the outer surfaces of inner circumferential ribs 24, as shown in FIG. 3, the fibrous material has a width less than the circumference of this cylindrical shape corresponding to inner circumferential ribs 24; similarly, when the fibrous material is engaged with outer pins 44 and longitudinally would along the cylindrical shape defined by the outer surfaces of outer circumferential ribs 38, as shown in FIG. 7, the fibrous material has a width less than the circumference of this cylindrical shape corresponding to outer circumferential ribs 38.
It is emphasized herein that any degree of commonality or differentiation between or among any of the material compositions actually used for the fibrous materials may be appropriate in accordance with a given embodiment of the present invention; hence, use herein, for example, of the terms "first" fibrous material, "second" fibrous material, and "third" fibrous material is not intended to suggest that the "first" fibrous material necessarily is either the same as or different from the "second" fibrous material, or that the "second" fibrous material necessarily is either the same as or different from the "third" fibrous material, or that the "first" fibrous material necessarily is either the same as or different from the "third" fibrous material.
After inner skin 22 of appropriate thickness is wound, inner circumferential ribs 24 running circumferentially around inner skin 22 are wound, using a filament-winding or tape-laying machine. With reference to FIG. 2, a second fibrous material is wound circumferentially around the cylindrical shape defined by the other surface of inner skin 22 so as to form a plurality of inner circumferential ribs 24 spaced apart axially and having equiradial outer surfaces defining a cylindrical shape which is coaxial with mandrel 20. FIG. 2 schematically illustrates inner circumferential ribs 24 wound over inner skin 22. Inner circumferential ribs 24 can be wound with or without the use of a dissolvable or sectional mold which is placed outside inner skin 22. If a dissolvable or sectional mold is utilized, this is removed after winding inner circumferential ribs 24.
Referring to FIG. 3, two inner pin rings 26 are positioned, one at each axial end of mandrel 20. Each inner pin ring 26 has an inner ring 28 portion and a plurality of inner pins 30 spaced apart circumferentially and projecting radially from inner ring 28, as shown in FIG. 10. Each inner ring 28 has an outer surface defining a cylindrical shape which is coaxial with mandrel 20 and approximately equiradial with the cylindrical shape defined by said outer surfaces of inner circumferential ribs 24.
A third fibrous material is engaged with inner pins 30 and wound longitudinally along the cylindrical shape defined by the outer surfaces of inner circumferential ribs 24 so as to form a plurality of inner longitudinal stringers 32 which are spaced apart circumferentially and correspondingly with inner pins 30 and have equiradial outer surfaces defining a cylindrical shape which is coaxial with mandrel 20.
It is emphasized that the present invention provides a unique methodology of allowing for tape or fiber placement over inner circumferential ribs 24, thus succeeding in winding intermediate skin 36 on top of circumferential ribs 24. Intermediate skin 36 cannot merely be wound directly onto inner circumferential ribs 24, since a continuous surface does not exist onto which the tape or fibers can be positioned. The present invention accomplishes this with the use of two pin rings 26, one positioned at each end of the wound piece. Inner pin rings 26 have a small cylindrical section, inner rings 28, of diameter approximately equal to that of the wound part. A series of inner pins 30, for some embodiments preferably equally spaced apart, extend in the radial direction outward from inner rings 28. Fibers or tapes are wound along the axis of the cylinder at some spacing, for some embodiments preferably about 1 inch, depending on dimensions. As the tape or filament winding machine makes a pass along the axis of the cylinder, the mandrel rotates a specified angular amount and traverses again along the axis of the cylinder. Typically, in the absence of inner pin rings 26, such a fiber or tape position would not remain, since it is not a geodesic path; however, in accordance with this invention, inner pin rings 26 keep the fibers or tapes in their axial position.
Reference now being made to FIG. 4, a fourth fibrous material is wound circumferentially around the cylindrical shape defined by the outer surfaces of inner longitudinal stringers 32 so as to form a pair of inner circumferential bands 34 located longitudinally inward of and adjacent to inner pin rings 26, inner circumferential bands 34 being spaced apart longitudinally and having equiradial outer surfaces defining a cylindrical shape which is coaxial with mandrel 20. Tapes or fibers are wound in the hoop direction at the ends of cylinder workpiece 18 to form inner circumferential bands 34, which provide a net force on inner longitudinal stringers 32 in the radial direction toward the interior of the cylinder.
Another continuous skin is wound over top inner longitudinal stringers 32 and inner circumferential bands 34, referring now to FIG. 5. Here, a fifth fibrous material is wound circumferentially around the cylindrical shape defined by the outer surfaces of inner longitudinal stringers 32 and inner circumferential bands 34 so as to form intermediate skin 36 having an outer surface defining a cylindrical shape which is coaxial with mandrel 20.
At this point, referring to FIG. 5, cylinder workpiece 18 comprises inner skin 22, a plurality of inner circumferential ribs 24, a pair of inner pin rings 26, a plurality of inner longitudinal stringers 32, a pair of inner circumferential bands 34, and intermediate skin 36. In order to add another ribbed layer to cylinder workpiece 18, steps pertaining to circumferential winding of ribs, positioning of pin rings, longitudinal winding of longitudinal stringers, circumferential winding of bands, and circumferential winding of a skin, are essentially repeated.
Referring to FIG. 6 and FIG. 9, a second set of ribs is wound over the skin, but with their positions displaced relative to the ribs located axially inward thereof. Here a sixth fibrous material is wound circumferentially around the cylindrical shape defined by the outer surface of intermediate skin 36 so as to form a plurality of outer circumferential ribs 38. Outer circumferential ribs 38 are spaced apart longitudinally and staggeringly with respect to inner circumferential ribs 24 and have equiradial outer surfaces defining a cylindrical shape which is coaxial with mandrel 20.
The specific positions of outer circumferential ribs 38 in relation to inner circumferential ribs 24 may be selected in accordance with both acoustical and structural design considerations. Selection of numbers and material compositions of inner circumferential ribs 24 and outer circumferential ribs 38 may also be relevant to these design considerations. For some embodiments, placement of outer circumferential ribs 38 is preferably translatedly uniform in relation to placement of inner circumferential ribs 24. For other embodiments of this invention, outer circumferential bands 38 are positioned variably or randomly in relation to successive inner circumferential ribs 24; in some embodiments and applications variable or random rib translation may provide enhanced vibrational energy dissipation. Also, for many embodiments of this invention inner circumferential ribs 24 and outer circumferential ribs 38 preferably provide stiffening for the composite cylinder with a minimum of weight.
Referring to FIG. 7, two outer pin rings 40 are positioned, one at each axial end of mandrel 20. Each outer pin ring 40 has an outer ring 42 portion and a plurality of outer pins 44 spaced apart circumferentially and projecting radially from outer ring 42, referring again to FIG. 10, which may be viewed as generally representative of the pin ring configuration in accordance with this invention. Each outer ring 42 has an outer surface defining a cylindrical shape which is coaxial with mandrel 20 and approximately equiradial with the cylindrical shape defined by said outer surfaces of outer circumferential ribs 38.
A second set of longitudinal stringers is wound in place with the use of the pin ring assembly, again resulting in a cylinder workpiece 18 structure such as that shown in FIG. 7. Here, a seventh fibrous material is engaged with outer pins 44 and wound longitudinally along the cylindrical shape defined by the outer surfaces of outer circumferential ribs 38 so as to form a plurality of outer longitudinal stringers 46 which are spaced apart circumferentially and correspondingly with outer pins 44 and have equiradial outer surfaces defining a cylindrical shape which is coaxial with mandrel 20.
It is emphasized that the pins for any of the pairs of pin rings in accordance with this invention may be relatively distantly spaced apart, or relatively closely spaced apart, for various embodiments of this invention; hence, the longitudinal stringers which engage a particular pair of pin rings will be correspondingly distantly or closely spaced apart, and may even be contiguous, with respect to each other. Therefore, for example, for some embodiments longitudinal stringers 30 form a continuous or substantially continuous surface if the spacings between pins 30 are sufficiently small and the band widths of longitudinal stringers 32 are sufficiently great; similarly, longitudinal stringers 46 form a continuous or substantially continuous surface if the spacings between pins 40 are sufficiently small and the band widths of longitudinal stringers 46 are sufficiently great.
Reference again being made to FIG. 4, which may be viewed as generally representative of circumferential winding of circumferential bands in accordance with this invention, an eighth fibrous material is wound circumferentially around the cylindrical shape defined by the outer surfaces of outer longitudinal stringers 46 so as to form a pair of outer circumferential bands 48 located longitudinally inward of and adjacent to outer pin rings 40, outer circumferential bands 48 being spaced apart longitudinally and having equiradial outer surfaces defining a cylindrical shape which is coaxial with mandrel 20. Thus, tapes or fibers are again wound in the hoop direction at the ends of cylinder workpiece 18, this time to form outer circumferential bands 48, which provide a net force on outer longitudinal stringers 46 in the radial direction toward the interior of the cylinder.
Another continuous skin is wound over top outer longitudinal stringers 46 and outer circumferential bands 48, now referring to FIG. 8, which shows the completion of cylinder workpiece 18 as a double-layered, translated rib-stiffened composite cylinder. Here, a ninth fibrous material is wound circumferentially around the cylindrical shape defined by the outer surfaces of outer longitudinal stringers 46 and outer circumferential bands 48 so as to form outer skin 50 having an outer surface defining a cylindrical shape which is coaxial with mandrel 20.
Accordingly, in this example a translated double rib-stiffened composite cylinder having a hollow core has been fabricated. This composite cylinder comprises: inner skin 22; a plurality of inner circumferential ribs 24 located radially outwardly adjacent to inner skin 22 and spaced apart longitudinally; a pair of inner pin rings 26 located at the axial ends of composite cylinder workpiece 18, one inner pin ring 26 at each axial end, each inner pin ring 26 having an inner ring 28 portion and a plurality of inner pins 30 spaced apart circumferentially and projecting radially from inner ring 28; a plurality of inner longitudinal stringers 32 located radially outwardly adjacent to inner circumferential ribs 24, inner longitudinal stringers 32 engaged with inner pins 30 and spaced apart circumferentially and correspondingly with inner pins 30; a pair of inner circumferential bands 34 located radially outwardly adjacent to inner longitudinal stringers 32 and longitudinally inwardly adjacent to inner pin rings 26; intermediate skin 36 located radially outwardly adjacent to inner circumferential bands 34 and inner longitudinal stringers 32; a plurality of outer circumferential ribs 48 located radially outwardly adjacent to intermediate skin 36, outer circumferential ribs 48 spaced apart longitudinally and staggeringly with respect to inner circumferential ribs 24; a pair of outer pin rings 40 located at the axial ends of composite cylinder workpiece 18, one outer pin ring 40 at each axial end, each outer pin ring 40 having an outer ring 42 portion and a plurality of outer pins 44 spaced apart circumferentially and projecting radially from outer ring 42; a plurality of outer longitudinal stringers 46 located radially outwardly adjacent to outer circumferential ribs 38, outer longitudinal stringers 46 engaged with outer pins 44 and spaced apart circumferentially and correspondingly with outer pins 44; a pair of outer circumferential bands 48 located radially outwardly adjacent to outer longitudinal stringers 46 and longitudinally inwardly adjacent to outer pin rings 40; and outer skin 50 located radially outwardly adjacent to outer circumferential bands 48 and outer longitudinal stringers 46.
It is reemphasized that the composite cylinder in accordance with the present invention is a translated multiple rib-stiffened composite cylinder having any plural number of ribbed layers. Hence, appropriate repetition of steps in accordance with this invention succeeds in conversion of the completed double-layered, translated rib-stiffened composite cylinder in the above example to a triple-layered cylinder, for example, which further comprises: a plurality of first additional outer circumferential ribs located radially outwardly adjacent to outer skin 50 and spaced apart longitudinally and staggeringly with respect to outer circumferential ribs; a pair of first additional outer pin rings located at the axial ends of cylinder workpiece 18, one first additional outer pin ring at each axial end, each first additional outer pin ring having a ring portion and a plurality of pins spaced apart circumferentially and projecting radially from the ring portion; a plurality of first additional outer longitudinal stringers located radially outwardly adjacent to the first additional outer circumferential ribs, the first additional outer longitudinal stringers engaged with the pins of the first additional outer pin rings and spaced apart circumferentially and correspondingly with the pins of the first additional outer pin rings; a pair of first additional outer bands located radially outwardly adjacent to the first additional outer longitudinal stringers and longitudinally inwardly adjacent to the first additional outer pin rings; and a first additional outer skin located radially outwardly adjacent to the first additional outer bands and the first additional outer longitudinal stringers.
Accordingly, in order to add each succeeding ribbed layer to cylinder workpiece 18, steps pertaining to circumferential winding of ribs, positioning of pin rings, longitudinal winding of longitudinal stringers, circumferential winding of bands, and circumferential winding of a skin, are appropriately repeated in accordance with this invention. Each repetition of steps forms a next outer layer of the composite cylinder, each next outer layer being radially outward of the previous other layer, the previous outer layer being the radially outermost outer layer prior to repetition of these steps. The previous outer layer includes previous circumferential ribs, previous pin rings, previous longitudinal stringers, previous bands, and a previous outer skin; the next outer layer includes the next circumferential ribs, the next pin rings, the next longitudinal stringers, the next bands, and the next outer skin, the next circumferential ribs spaced apart longitudinally and staggeringly with respect to the previous circumferential ribs.
Other embodiments of this invention will be apparent to those skilled in the art from a consideration of this specification or practice of the invention disclosed herein. Various omissions, modifications and changes to the principles described may be made by one skilled in the art without departing from the true scope and spirit of the invention which is indicated by the following claims. | A multiple-layered, translatedly rib-stiffened, composite hollow cylinder and method for fabrication thereof utilizing filament winding techniques known in the art. An inner skin is wound over a mandrel; then, circumferential ribs are wound over the inner skin, pin rings are placed at the axial ends of the mandrel, longitudinal stringers are engaged with the pin rings and wound over the circumferential ribs, circumferential bands are wound near the axial ends over the longitudinal stringers, and another skin is wound over the circumferential bands and longitudinal stringers; these steps, commencing with the winding of circumferential ribs and concluding with the winding of an additional skin, are repeated as many times as desired, each repetition forming an additional layer, with the circumferential ribs for each additional layer being longitudinally staggered in relation to the circumferential ribs for the previous layer. The cylinder in accordance with this invention is a superior enclosure in terms of mechanical vibrational energy dissipation, directionally controllable thermal energy transmission, and structural damage tolerance; moreover, it advantageously permits a continuous fabrication procedure. | 5 |
FIELD OF THE INVENTION
The present invention relates to improvements in construction devices and methods, and more particularly to devices and methods that improve the functionality of scaffolding typically used in construction and remodeling.
BACKGROUND OF THE INVENTION
Scaffolding has many uses, particularly for the construction and maintenance of buildings. A scaffold assembly can be used as a single tier, but is usually formed to allow stacking of the scaffold assembly so that many tiers may be joined to provide workers with the ability to reach great heights above the ground or above a particular floor in a building. Very often, the tiers of a scaffold may be so high that they must be tied to a building to prevent accidents. Several tiers of scaffolding being so stacked can become unstable, which may be exacerbated by the movements of the workers, by high winds, and by other natural and man-made factors.
But when scaffolds are used during the construction process within a building utilizing steel I-beam construction, stability does not generally pose a serious problem, and instead, mobility is a factor to be considered. The mobility of the scaffold may adversely impact productivity, even where the scaffold assembly might only be one or two tiers high, while working on an individual floor of a modern building. The scaffolding would therefore not need to be tied to a wall, and conversely may need to be constantly relocated to various positions throughout the building's floor.
The worker's productivity may be limited by mobility, due to the methodology utilized in steel I-beam construction. The initial phase of construction for the building often involves the substructure, in which piles may be driven down to reach bedrock, alternatively, shafts may be drilled, into which steel reinforcing rods are inserted, and the shafts are then filled with concrete. A foundation platform consisting of reinforced concrete is then poured above the support columns. Rising up from the foundation platform is the superstructure. A common method of forming the building's superstructure for modern office buildings and skyscrapers involves erecting steel I-beam columns, to which are attached steel girders and cross-beams that form a steel skeleton.
Steel Decking is then attached to the horizontal I-beams, usually being welded in place. The decking typically consists of panels of thin corrugated steel. An early example of the steel decking that may be used is illustrated in FIG. 5 of U.S. Pat. No. 757,519 to Turnbull, which has “cylindric corrugations.” A later example is shown by U.S. Pat. No. 4,453,364 to Ting which generally has flat surfaces-peaks, valleys, and sloping webs that form trapezoidal corrugations.
It has been known for some time, in the art of construction, to attach anchor studs to steel I-beams to serve as a shear transfer element, which is shown by U.S. Pat. No. 2,987,855 to Singleton. Singleton also shows use of steel decking that has wave-like corrugations, and which appear more sinusoidal than cylindric. It is also quite common to weld steel anchor studs to the decking at the I-beam locations, with one such approach being shown by U.S. Pat. No. 3,363,379 to Curran. Generally, at some optimum point in the construction sequence thereafter, concrete is poured over the corrugated decking and anchor studs to establish the particular floor of the building. However, before the concrete is actually poured, and after the decking and the studs have been secured to provide a stable platform, many other steps are performed to facilitate the overall construction of each floor, including installation of diagonal side bracing, which requires use of scaffolding.
At this point in the construction, the scaffolding must be placed atop the steel decking in a manner that makes it stable, despite only having periodic support from the corrugations. It is not uncommon to bolt the base plates of the scaffold shown in FIG. 7 , to a series of wood planks which may form a rectangular base. But the scaffold then must be lifted and carried from position to position about the decking, which might require removal of the wood planks in order to reduce the weight of the scaffold assembly being transported.
The multi-directional transport device disclosed herein may be attached to each base of a typical scaffold, to provide a more efficient means of relocating the scaffolding about the decking without use of wood planking, and without the need to lift and carry the assembly, possibly eliminating the need for the assistance of a second worker.
OBJECTS OF THE INVENTION
It is an object of the invention to provide a means for supporting a scaffold assembly on the corrugated steel decking of a building's I-beam superstructure.
It is also an object of the invention to provide a means of stabilizing a scaffold assembly when being utilized atop the corrugated steel decking of a building's I-beam superstructure.
It is another object of the invention to provide a scaffold support device that can remain affixed to the scaffold during its transportation.
It is a further object of the invention to provide a device which may increase the mobility of a scaffold assembly while being utilized atop the corrugated steel decking of a building's I-beam superstructure.
It is another object of the invention to provide a device which may be attached to the base of a scaffold assembly and permit the scaffold to slide across the corrugations of the steel decking of a buildings sub-floor.
SUMMARY OF THE INVENTION
The present invention is directed to providing improved mobility to a typical scaffold assembly being utilized in the maintenance of buildings or at building construction sites. A conventional scaffold assembly is shown in FIG. 7 , and typically has a plurality of legs to provide support, which usually terminate in a flat base in order to provide stability. Where the scaffold is principally utilized in a single location for a substantial period of time, scaffold mobility is not a significant factor. However, where scaffolding is utilized on individual floors of a new multi-story building, mobility may be an important factor, as it may affect productivity. This is especially true where the building is constructed using a standard I-beam superstructure with corrugated floor decking having vertical anchor studs.
To facilitate increased mobility of a construction scaffold in that scenario, and thereby increase productivity, the multi-directional scaffold device herein disclosed may be attached to the scaffold's legs. The device comprises an elongated flat plate with an angled extension at respective ends of the flat plate. The length of the elongated flat plate may be chosen to always obtain support from at least two peaks of the corrugated steel decking. The angled extensions may be have a trapezoidal shape, or may alternatively have a triangular shape. The angled extensions may also be flat, or they may alternatively curve upwards. They may additionally have curvature in two directions, resulting in a compound curved surface. These variations for the angled extensions may be incorporated to provide a means of having tangential contact of the multi-directional transport device with the anchor studs of the floor deck, and thereby greatly reduce the possibility of jamming on an anchor stud due to direct contact from a flat surface, which would impede ease of scaffold movement by a single worker.
The multi-directional scaffold device may have vertical walls incorporated into it to provide stiffness, which may be necessary where the scaffold being supported will be very heavy. These walls may comprise integral stiffeners, or may alternatively be separate flanges which are welded to the elongated flat plate and angled extensions. The stiffeners may also be in the form of other geometric shapes, such as an angle, which may be fastened, rather than welded, to the elongated flat plate and angled extensions.
To facilitate attachment of the multi-directional transport device to the scaffold, the device may incorporate threaded studs that protrude vertically from the top of the elongated flat plate. Holes may be drilled in the flat base of the scaffold legs to receive the studs, and nuts may then be threaded onto the studs to removeably attach the device to the scaffold.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view and side view of a first embodiment of the multi-directional scaffold transport device.
FIG. 2 is a top view, side view, and section cut through a second embodiment of the multi-directional scaffold transport device, shown with threaded studs.
FIG. 3 is a top view, side view, and section cut through a third embodiment of the multi-directional scaffold transport device.
FIG. 4 is a top view and side view of a fourth embodiment of the multi-directional scaffold transport device.
FIG. 5 is a top view and side view of a fifth embodiment of the multi-directional scaffold transport device.
FIG. 6 is a top view and side view of a sixth embodiment of the multi-directional scaffold transport device.
FIG. 7 is a perspective view of a typical construction scaffold.
FIG. 8 is a section view of the second embodiment of the multi-directional scaffold transport device, shown attached to the base of a construction scaffold, and sitting atop the corrugated steel decking of a building's superstructure.
FIG. 9 is an exploded view of a modified leg and base of a scaffold.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a first embodiment of the multi-directional scaffold transport device 20 of the present invention. The multi-directional scaffold transport device 20 may be constructed of any appropriate material, including, but not limited to, aluminum, steel, titanium, brass, phenolic, plastic, or wood. The multi-directional scaffold transport device 20 may be formed from sheet metal comprised of multiple bends, or it may be an assembly of parts fastened or welded together, or it may be a casting, or a machined part. The method of manufacture and the material utilized to produce the device may be determined by the manufacturer, and may be specially selected to suit the particular scaffolding and building site.
The multi-directional scaffold transport device 20 in FIG. 1 may be comprised of an elongated flat plate 21 , which may be defined as having a top surface 22 , a bottom surface 23 , which may be substantially flat, a first end 24 , a second end 25 , a first side 26 , and a second side 27 . In a preferred embodiment the first end 24 and second end 25 are generally parallel to each other, and first side 26 and second side 27 are also generally parallel to each other, to generally form a rectangular-shaped plate. The length of the first side 26 and second side 27 are approximately equal, and each of which may be several times longer than the length of first end 24 and second end 25 , which themselves are approximately equal to each other in length.
Extending from first end 24 may be a first angled extension plate 30 . First angled extension plate 30 may be integral to first end 24 of elongated flat plate 21 , and thus may simply be a bent up sheet metal flange extending therefrom, or alternatively it may be mechanically fastened onto or welded to first end 24 of elongated flat plate 21 . A second angled extension plate 40 may extend from second end 25 just the same as is herein described for first angled extension plate 30 extending from first end 24 .
First angled extension plate 30 may be described as having a top 31 , a bottom 32 , a fixed end 33 , an elevated end 34 , a first tapered side 35 , and a second tapered side 36 . In a preferred embodiment, first tapered side 35 and second tapered side 36 both angle towards each other, so that the width of the plate narrows in moving from fixed end 33 to elevated end 34 . In one embodiment, first tapered side 35 and said second tapered 36 side may terminate on a flat edge surface 37 at elevated end 34 , for both the first and second angled extension plates 30 and 40 . Where the flat edge surface 37 is formed to be parallel to the fixed end 33 , the first angular extension plate and second angular extension plate will each roughly have a trapezoidal shape.
First angled extension plate 30 may be a flat plate such that top 31 and bottom 32 are planar and parallel to each other ( FIG. 1 ). In a preferred embodiment, first angled extension plate 30 may be flat and so formed to create acute angle 29 relative to the top surface 22 and bottom surface 23 of elongated flat plate 21 .
The length of the elongated flat plate 21 of the multi-directional scaffold transport device 20 may preferably be sized to span between the peaks of the corrugations of the floor decking shown in FIG. 5 of U.S. Pat. No. 757,519 to Turnbull, or as shown in FIG. 5 of U.S. Pat. No. 3,177,619 to Benjamin, or those in FIG. 2 of U.S. Pat. No. 3,363,379 to Curran. Although the spacing of the peaks of the corrugations used today for the floor decking may vary from building to building, corrugations with a six inches spacing is quite common. Therefore the length of flat plate 21 may, in that instance, be approximately twelve inches or slightly longer, so that when it is attached to the base 13 of a scaffold assembly 11 ( FIG. 7 ), which is being maneuvered across the floor deck's corrugations, the device will always be supported by at least two peaks. This will be the case where the decking has trapezoidal corrugations offering more stable support from its flat peak surfaces, or the wave-like corrugations. However, the length may be modified to be shorter or longer to suit less common spacing between corrugations, or similar obstacles in other applications.
The multi-directional scaffold device 20 may be required to support a scaffold having tools or other items atop of it or attached to it, making the overall combined weight to be supported a significant design factor. Therefore, the scaffold device 20 may preferably have vertical stiffeners 51 which may be integral, and may protrude upward from first side 26 and second side 27 of elongated flat plate 21 ( FIG. 3 ). Many alternative embodiments that incorporate vertical stiffeners are possible. A continuous integral wall 52 may protrude vertically from the first end 24 , second end 25 , first side 26 , and a second side 27 of first angled extension plate 30 to form a rectangular-shaped enclosure, as shown in FIG. 4 . Alternatively, a continuous wall 53 may protrude vertically from only the periphery of the multi-directional transport device, and thereby protrude from first side 26 and second side 27 of elongated flat plate 21 , from first tapered side 35 and second tapered side 36 of both first and second angled extension plates 30 and 40 , and from elevated end 34 , as shown in FIG. 5 . Also, those various possible stiffener arrangements—stiffeners 51 , 52 and 53 —instead of being integrally formed, may comprise separate parts which are attached to the device. Shown in FIG. 2 , is an embodiment where L-shaped angles 54 of different lengths are attached to the periphery of the device to provide stiffness. The attachment means of the angles 54 may include, but is not limited to, welding, and mechanical fasteners such as rivets, screws, nut and bolts, etc.
To function as an integral part of a typical scaffold, the multi-directional transport device must necessarily be fixed to the scaffolding being used at a particular construction site. A typical scaffold 11 ( FIG. 7 ) may have a leg 12 , that terminates in a base 13 . While there are many possible schemes for attachment of the device to the scaffold base, including, but not limited to, welding, and mechanical fasteners such as rivets, screws, nut and bolts, etc, a preferred embodiment may incorporate threaded studs 60 into the multi-directional transport device 20 that may protrude vertically from top surface 22 of the elongated flat plate 21 ( FIG. 2 ). They may be integral to the elongated flat plate or attached to it by any suitable means, including, but not limited to, welding the threaded studs thereon. Two or more threaded studs 60 would likely be sufficient to attach the device to the base 13 of scaffold 11 , but in a preferred embodiment, four threaded studs 60 may protrude from top surface 22 of the elongated flat plate 21 , and may preferably be spaced in a rectangular pattern. The pattern may preferably be centrally located so as to be approximately mid-way between first end 24 and said second end 25 of said elongated flat plate 21 , and approximately mid-way between said first side 26 and second side 27 . The spacing between adjacent threaded studs 60 should be sufficient to provide adequate clearance from the leg 12 of scaffold 11 .
The base 13 of scaffold 11 may have holes 14 drilled into it to provide a clearance fit for acceptance of the studs 60 . The multi-directional scaffold device 20 may then be removably attached to scaffold 11 using a conventional fastening mean including, but not limited to, standard hex nuts 65 with lock washers, jam nuts, lug nuts, wing nuts, etc ( FIG. 8 ). The attachment scheme may alternatively incorporate a quick release fastening means for ease of assembly and disassembly onto the base 13 of scaffold 11 .
Maneuvering of the scaffold assembly 11 would be facilitated with the multi-directional transport device attached, as in FIG. 8 , to permit sliding movement of the scaffold assembly atop the exposed floor decking of a building's superstructure, as shown in FIG. 9 . The relative sliding movement will occur between the bottom surface 23 of multi-directional transport device 20 , and the peaks of the corrugations. The sliding motion will initially be resisted by a static frictional force, which is a threshold that must be overcome, and thereafter by a lesser sliding frictional force. The friction force resisting movement, F f , is determined from the equation, F f =μ·F n , where F n is the normal force or weight of the scaffold being moved, and μ is the coefficient of friction.
A coefficient of friction is an empirical property of two materials which are contacting each other, and which provides the relative motion between the two objects. The coefficient can range from near-zero to greater than one, and rougher surfaces have higher coefficients, but most dry material in combination have friction coefficient vales between 0.3 and 0.7. For example, ice on steel has a very low coefficient, whereas a rubber tire on concrete may, under certain conditions, have a coefficient of 1.7. As the coefficient varies dramatically from material to material, this may be a consideration in the material selection for the multi-directional scaffold transport device. The corrugated decking will typically be steel, so materials having a low coefficient of friction in relation to the steel will optimize sliding movement of the scaffold. Teflon has a very low coefficient of friction, often being as little as 0.04, and as such, it is commonly used in spherical bearings.
The multi-directional transport device 20 may need to be constructed of a relatively high strength metal, but it could also be coated with a finish having a low coefficient of friction, such as Teflon, and enhance sliding movement. Additionally, although there would be a tendency to wear away a coating like Teflon because of the scaffold's considerable weight and frequent usage, adding a lubricant to the bottom surface 23 , whether coated or not, would improve sliding movement as well as the device's longevity. The material selected for the multi-directional transport device 20 and any coating that may be used will also alleviate fretting between the moving surfaces.
As described previously, the length of the elongated flat plate 21 needs to be roughly as long as the straight-line distance between two peaks of the corrugations in the floor decking being utilized ( FIG. 9 ). It should be apparent that the first and second angled extensions permit bi-directional movement of a scaffold fitted with the device, and they also serve to allow the device to climb up to the peak of a corrugation where the scaffold may be maneuvered at an angle relative to the corrugations. With adjustments to the length of the device, a preferred embodiment may traverse at 15 degree angles relative to the axis of the corrugations, or in a more preferred embodiment, traverse at 30 degree angles, but in the most preferred embodiment may traverse at angles of 60 to 90 degrees relative to the axis of the corrugations.
The device accomplishes multi-directional movement, and not simply bi-directional movement, because many scaffold assemblies incorporate a lever 15 that allow for height adjustments of a particular leg, along with rotation of the base 13 , such as U.S. Pat. No. 6,722,471 to Wolfe. Rotation of the base 13 would also accomplish rotation of the axis 28 of the multi-directional transport device 20 to be re-oriented at a different angle relative to the corrugations. The re-orientation would permit a scaffold that had been pushed diagonally across the floor deck corrugations—at a 45 degree angle for example—to a position where a task was completed, to then have each leg rotated so that the scaffold could then be pushed in a direction at a 90 degree angle relative to its original path, essentially zigzagging across the decking, without having to push the heavy scaffolding along a curved path.
Although older scaffolding may not be equipped with a lever 15 to permit rotation of the scaffold base, a scaffold leg may nonetheless be fitted with a pivoting base 70 having a base plate 71 and post 72 , as seen in FIG. 9 . The post 72 may have one or more pairs of orifices 73 drilled in-line through the post 72 , and pairs of holes may similarly be drilled in line in scaffold leg 12 . The leg may then be removeably secured to the based using clamp 80 , which resembles a “C”-clamp that has a “C”-shaped body 81 , which threadably retains a pair of screws 82 . Each screw 81 may have a handle 83 capable of accommodating rotational movement of the screw, so that when the post 71 of base 71 is inserted into the scaffold leg 13 , the ends 84 of clamp 80 may be driven into the in-line holes 74 of the post and the in-line holes 73 of the base. With the scaffold so equipped, and positioned atop corrugated decking, zigzag movement may be accomplished as described for newer scaffolding, by backing out the screws 82 and rotating the base 70 , so as to reorient the multi-directional transport device 20 .
The maneuverability of the scaffold assembly, with the device attached to the base of each leg, may be further improved in one of several possible alternate embodiments. In one alternate embodiment, first tapered side 35 and second tapered side 36 may converge at the elevated end 34 for first and second angled extension plates 30 and 40 , and rather than a flat edge surface 37 being formed, first and second tapered sides 35 and 36 may converge to create a sharp edge (not shown). This would result in the first angular extension plate 30 and the second angular extension plate 40 each generally taking the form of a triangular shape. Alternatively, instead of converging to a sharp edge at the elevated end 34 , the first and second tapered sides 35 and 36 may be radiused to form a curved surface 38 ( FIG. 6 ), which may be tangent to elevated end 34 .
It can be seen that curved surface 38 may assist in maneuvering the multi-directional transport device 20 , when attached to a scaffold assembly, around any of the upward protruding floor deck anchor studs. The curved surface 38 would serve to guide the device/scaffold laterally to one side or the other of a floor deck anchor stud, rather than jamming on or butting against the anchor stud.
Additionally, instead of angled extension plates 30 and 40 having a top 31 and bottom 32 which would be planar and parallel to each other ( FIG. 1 ), they may both arch upwards whereby first angled extension plate 30 is formed by a curved top 31 A and curved bottom 32 A ( FIG. 3 ). Furthermore, the top and bottom may be comprised of compound curved surfaces, whereby they may also curve upward when moving laterally from centerline 28 , so that first and second angled extension plates 30 and 40 are shaped like the bow of a ship (not shown). This would further ensure that only a curved surface of the multi-directional scaffold device would contact the anchor stud, and prevent jamming against the stud, which would require the user to relocate to the side of the scaffold to jockey it sideways around the stud, rather than just pushing the scaffold from behind. It should be pointed out that the multi-directional scaffold transport device 20 , as well as any alternate embodiment, may preferably be symmetrically formed relative to centerline 28 .
Lastly, maneuvering the scaffold around the floor deck anchor studs may be further accommodated in an alternate embodiment by having elongated flat plate 21 also incorporate, into first side 26 and second side 27 , tapered edges 26 A and 27 A respectively ( FIG. 6 ).
The examples and descriptions provided merely illustrate a preferred embodiment of the present invention. Those skilled in the art and having the benefit of the present disclosure will appreciate that further embodiments may be implemented with various changes within the scope of the present invention. Other modifications, substitutions, omissions and changes may be made in the design, size, materials used or proportions, operating conditions, assembly sequence, or arrangement or positioning of elements and members of the preferred embodiment without departing from the spirit of this invention as described in the following claims. | A multi-directional scaffold transport device, which may be attached to each base of a scaffold's legs, provides increased mobility in relation to movement atop corrugated floor decking with vertical anchor studs used in conventional steel I-beam superstructures. The device comprises an elongated flat plate with angled extensions. The angled extensions may form a trapezoidal shape, or more preferably a triangular shape, and may be curved or have compound curvature to enable deflection of the device to either side of any anchor stud encountered, rather than jamming thereon. The elongated flat plate may have minimal length sufficient to normally receive support from at least two peaks of the corrugated decking. The device may incorporate threaded studs protruding from the elongated flat plate, which may be received by holes in the base of the scaffold, and be removeably fastened thereto using nuts. The device may also incorporate vertical walls for increased stiffness. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a current control system for a linear solenoid and, more particularly, to a current control system for a linear solenoid, as used for controlling the oil pressure of an automatic transmission to be mounted on a vehicle.
2. Related Art
Generally speaking, a linear solenoid used to control oil pressure is designed to have a proportional relation, as illustrated in FIG. 13, between a current value I (mA) to be applied to the linear solenoid and an oil pressure (P). In short, the oil pressure (P) of a hydraulic circuit increases with the increase in the current value I (mA). A clutch pressure is produced by the oil pressure (P).
A command current value is set for producing the desired clutch pressure according to the running state of the vehicle. The command current value thus set is corrected to an output current in accordance with the difference from the value of the current that is actually flowing through the linear solenoid. Moreover, a voltage value is set on the basis of an output current and the resistance value of the linear solenoid, as stored in a memory unit, so that the voltage is applied to the linear solenoid by a solenoid drive circuit in response to a signal coming from a PWM output part.
The resistance value of the linear solenoid changes according to its ambient temperature. In short, the resistance value of the linear solenoid increases in proportion to the rise in the temperature of the oil in contact with the linear solenoid.
In the prior art described above, however, the output voltage value to the linear solenoid is set by a feedback control on the basis of the corrected output current and the resistance value stored in the memory unit. At a cold run, for example, the oil temperature is so low that the resistance value of the linear solenoid is actually low. However, the resistance value used when the voltage value is to be set is a fixed value retrieved from the memory unit and based on the oil pressure in a steady run. Therefore, the resistance value used is not equal to the real resistance value of the linear solenoid. As a result, the actual current flowing through the solenoid exceeds the command current. In an overheat state, on the other hand, the oil temperature rises to raise the actual resistance value so that the actual current flowing through the solenoid becomes low.
Because the feedback control is performed by monitoring the real current flow, a current value different from the desired target value, is outputted for a long time so that the clutch pressure control is influenced to cause a shift shock. Moreover, this shift shock always occurs under cold run or overheat conditions.
SUMMARY OF THE INVENTION
An object of the present invention is to solve the above-specified problems and to provide a current control system for a linear solenoid, which can control the current of a linear solenoid accurately in any temperature circumstance.
In order to achieve the above-specified object, according to the present invention, there is provided:
A current control system for a linear solenoid for feedback-controlling an output voltage value on the basis of a difference between a command current value to the linear solenoid, as set according to a vehicle running state, and a feedback current value, as produced by monitoring a current value actually being fed through the linear solenoid. The current control system includes decision means for deciding whether or not the resistance value of the linear solenoid can be calculated; real resistance value calculating means for calculating a real resistance value on the basis of a signal coming from said decision means, the command current value and the output voltage value; comparison means for comparing the calculated real resistance value and a resistance value in a memory unit; and correction means for correcting the resistance value in the memory unit on the basis of the comparison result of the comparison means, wherein the output voltage value is outputted on the basis of the corrected resistance value.
As a result, even if the resistance value of the linear solenoid is changed by the ambient temperature such as the oil temperature, the real resistance value is calculated and the output voltage value is applied to a solenoid drive circuit on the basis of the real resistance value so that the linear solenoid can always be controlled with the correct current to avoid shift shock.
Thus, it is possible to prevent the output characteristics of the linear solenoid from being changed by the temperature.
Furthermore, the present invention does not require the use of any oil temperature sensor, so an accurate resistance value can be learned while minimizing the number of parts.
In a current control system for a linear solenoid as set forth above, the decision means decides whether or not the difference between the command current value and the feedback current value is within a predetermined range. The real resistance value calculating means calculates the resistance value when the difference between the command current value and the feedback current value is within the predetermined range.
This will be described with reference to the case of a resistance value of 3 Ω of FIG. 9. When the real resistance value is to be calculated, it is determined from the command current value and the output voltage value. From a time of 0 milliseconds to a time of 300 milliseconds in FIG. 9, the command current value and the feedback current value deviate so greatly that an accurate resistance value cannot be determined. Even if, on the other hand, the real resistance value is to be calculated based on the feedback current value rather than the command current value, the feedback current may lag a change in output voltage by as much as 10 milliseconds when the feedback current is 1370 mA at a time of 100 milliseconds in FIG. 9. As a result, the voltage value at a time of 100 millisecs and the feedback current value do not correspond to each other, thereby making it difficult to calculate an accurate resistance value. By calculating the resistance value only when the difference between the command current and the feedback current is within a predetermined range, as in the present invention, a current value corresponding to the output voltage value can be achieved to calculate an accurate resistance value.
In a current control system for a linear solenoid as set forth above, the correction of the resistance value is set according to the difference between the calculated real resistance value and the resistance value in the memory unit.
By making the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small, the real resistance value can be quickly approached when the difference is large, and the correction of the resistance value is suppressed as much as possible when the difference is small, so that the noise resistance can be improved to control the current stably.
In a current control system for a linear solenoid as set forth above, a current is always applied within a certain period of time after an engine start, even if the linear solenoid is inoperative (so as to maintain the inoperative state.)
By applying the current at all times, therefore, the resistance value can always be learned. As a result, during a predetermined time period after the engine start, the resistance value learning is performed immediately so that accurate current control can be performed immediately after the start of the vehicle.
In a current control system for a linear solenoid as set forth above, the number of corrections per unit time is increased for a predetermined time period after the engine start.
Immediately after the engine start, the difference between the stored resistance value and the real resistance value frequently grows especially large. Therefore, the resistance value can be quickly set to the real value by increasing the number of corrections.
The current control system for a linear solenoid according to an embodiment of the present invention provides for feedback-controlling of an output voltage value on the basis of a difference between a command current value for the linear solenoid, as set according to a vehicle running state, and a feedback current value, as produced by monitoring a current value actually flowing through the linear solenoid. The current control system includes temperature detecting means for detecting the oil temperature of an automatic transmission; real resistance value setting means for setting the real resistance value of the linear solenoid on the basis of the detected oil temperature; comparison means for comparing the set real resistance value and a resistance value in a memory unit; and correction means for correcting the resistance value in the memory unit on the basis of the comparison result of the comparison means, wherein the output voltage value is outputted on the basis of the corrected resistance value.
By correcting the real resistance value recorded in memory for the linear solenoid when the resistance value is changed by the ambient temperature, such as the oil temperature, the output voltage is applied to the solenoid drive circuit on the basis of the real resistance value so that the solenoid can always be controlled with the correct command current. Thus, it is possible to prevent the output characteristics of the linear solenoid from being changed with the temperature.
According to the present invention, when the difference between a command current value ir and a feedback current value ifb is within a predetermined range, as shown in FIG. 2, a resistance value R in Ohms is calculated by the equation R=output voltage value Vr (volts)×1,000/command current value ir (in mA). This equation allows the determination of the resistance value of the linear solenoid, which is used to determine a feed forward gain KR of the feedback control.
By learning the resistance value of the linear solenoid from the output voltage value Vr and the command current value ir, the responsiveness of the linear solenoid can be equalized for any oil temperature range, thus suppressing shift shock. In short, the oil pressure responsiveness at a low oil temperature and at a high oil temperature can be improved.
By performing the resistance value learning control of the present invention, as shown in FIG. 8, the command current value can be quickly stabilized to a value (e.g., 1,200 mA) for any oil temperature range.
In the prior art, the current highly overshoots when the oil temperature is low so that the resistance value is low, as illustrated in FIG. 9. The current rises slowly when the oil temperature is high so that the resistance value is high. Therefore, the rise of the oil pressure is changed by the oil temperature, and shift shock is produced.
In an embodiment of the present invention, whether or not the resistance value of the linear solenoid can be calculated can be decided depending upon whether or not the difference between the modulator current command value and the monitor current value is within the predetermined range. The decision on whether or not the resistance value of the linear solenoid can be calculated may also be made on the basis of the change in the output voltage value or on the basis of elapsed time.
Moreover, the oil temperature indicating the ambient temperature of the linear solenoid may be detected to learn the resistance value on the basis of the oil temperature.
The resistance value of the linear solenoid may also be determined on the basis of the engine water temperature in place of the oil temperature sensor, however the accuracy drops.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing the entire construction of a current control system for a linear solenoid according to an embodiment of the present invention;
FIG. 2 is a diagram showing a current control system of the linear solenoid according to an embodiment of the present invention;
FIG. 3 is a main flow chart of the current control of the linear solenoid of the present invention;
FIG. 4 is a flow chart of the initialization of the current control of the linear solenoid of the present invention;
FIG. 5 is a flow chart of the current control of the linear solenoid of the present invention;
FIG. 6 is a flow chart showing the resistance value learning control in conjunction with the current comparison of the present invention;
FIG. 7 is a flow chart for setting the resistance learning period T3 of the linear solenoid of the present invention;
FIG. 8 is a current feedback waveform diagram of the case of the resistance learning of the present invention;
FIG. 9 is a current feedback waveform diagram of the case of no resistance learning of the prior art;
FIG. 10 is a flow chart showing the resistance value learning control by the voltage value change of the present invention;
FIG. 11 is a flow chart showing the resistance value learning control by the timer of the present invention;
FIG. 12 is a flow chart showing the resistance value learning control by the oil temperature detection of the present invention;
FIG. 13 is a diagram illustrating a relation between a current value to be fed to the linear solenoid and an oil pressure to be produced thereby; and
FIG. 14 is a diagram illustrating a relation between the oil temperature and the resistance value of the linear solenoid.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 is a diagram showing the entire construction of a current control system for a linear solenoid according to an embodiment of the present invention, and FIG. 2 is a diagram showing a current control system of the linear solenoid.
In FIG. 1: reference numeral 1 designates an oil temperature sensor; numeral 2 a vehicle speed sensor; numeral 3 a throttle opening sensor; numeral 4 a linear solenoid; numeral 5 a pressure regulating mechanism; numeral 6 a modulator valve arranged in the line pressure (PL) system; numeral 7 a clutch; and numeral 8 a pressure regulating valve for regulating the oil pressure to be fed to the clutch.
Numeral 10 designates an electronic control unit which is composed of: a clutch oil pressure operation part 11 connected with the oil temperature sensor 1, the vehicle speed sensor 2 and the throttle opening sensor 3, individually; an oil pressure/current converting part 12 connected with the clutch oil pressure operation part 11; a current comparing part 13 connected with the oil pressure/current converting part 12; a PI (proportional and integral) control part 14 connected with the current comparing part 13; a PWM output part 15 (pulse width modulator) connected with the PI control part 14; and a solenoid drive circuit 18 connected with the PWM output part 15 to feed its output to the linear solenoid 4. With this linear solenoid 4, there is connected a solenoid current monitor circuit 19, with which is connected an AD (analog-to-digital) value/current converting part 20 to feed back its output to the current comparing part 13.
This feedback control system has a construction, as shown in FIG. 2. Specifically, the PI control part 14 has a feed forward gain KR, a proportional gain KP and an integral gain KI so that an output voltage Vr, as based on the output coming from the PI control part 14, is applied to the linear solenoid 4. The solenoid current of the linear solenoid 4 is monitored and subjected to a voltage/current conversion so that a feedback current value ifb is compared in the current comparing part 13 with a command current value ir until it is fed back.
In the present invention, moreover, the outputs of the oil pressure/current converting part 12, the current comparing part 13 and the PI control part 14 are connected with a resistance operation·comparison·correction part 16 capable of transferring data with a memory unit 17, the data of which can be read out to the PI control part 14.
Specifically, when the difference between the command current value ir and the feedback current value ifb is within a predetermined range, the resistance value R is calculated by R=the output voltage value Vr×1,000/the command current value ir to determine the resistance value of the linear solenoid 4 thereby to set it as the feed forward gain KR of the feedback control.
Here, the output voltage value Vr=(ir×KR)+(ie×KP)+KI∫ie·dt.
In the present invention, as described above, by learning the resistance of the linear solenoid from the output voltage and the command current value, the feed forward gain KR can be properly changed to equalize the responsiveness of the linear solenoid for any oil temperature range, thereby suppressing the dispersion of a shift shock.
Specifically, the oil pressure responsiveness at a cold oil temperature or at a high oil temperature can be improved to reduce the dispersion of the shift shock.
In short, a tuning of higher accuracy can be effected to damp the shift shock.
Here will be specifically described the current control of the linear solenoid of the present invention.
FIG. 3 is a main flow chart of the current control of the linear solenoid of the present invention.
(1) First of all, the current control system of the linear solenoid is initialized (at Step S1).
(2) Next, the current of the linear solenoid is controlled (as shown in a later-described current control flow chart of FIG. 5) (at Step S2).
(3) Next, the resistance value learning of the linear solenoid is controlled (as shown in a later-described resistance value learning control flow chart of FIG. 6) (at Step S3).
The initialization is performed as follows:
FIG. 4 is a flow chart of the initialization of the current control of the linear solenoid of the present invention.
(1) First of all, it is checked (at Step S11) whether or not a predetermined time T1 has elapsed after an engine start. A lapse time is taken because it is usual for the power supply to be unstable for about 100 milliseconds after the engine start.
(2) After the predetermined time T1 has elapsed, the resistance of the linear solenoid is then set (at Step S12) to its initial value.
(3) Next, the current value of the linear solenoid is set (at Step S13) to its initial value.
(4) Next, a resistance learning period T3 of the linear solenoid is set (at Step S14).
FIG. 5 is a flow chart of the current control of the linear solenoid of the present invention as referred to in step S2 of FIG. 3.
(1) At first, the vehicle running state is detected (at Step S21) on the basis of the data coming from the vehicle speed sensor 2, the throttle opening sensor 3 and the oil temperature sensor.
(2) Next, the clutch pressure is set (at Step S22).
(3) Next, the command current value ir is set (at Step S23).
(4) Next, the actual current value is compared with the command current (at Step S24) at the current comparing part 13.
(5) Next, the output voltage value is set (at Step S25) at the PI control part 14. In short, the voltage value Vr to be outputted is set according to the difference between the command current value ir and the feedback current value ifb.
(6) Next, the PWM signal is outputted (at Step S26) from the PWM output part 15 to the linear solenoid.
Here will be described the aforementioned resistance value learning control.
The resistance value learning control of step S3 in FIG. 3 is shown in detail in FIG. 6.
FIG. 6 is a flow chart showing the resistance value learning control by the current comparison of the present invention.
(1) At first, it is checked (at Step S31) whether or not the resistance learning period T3 has elapsed.
(2) Next, if the predetermined time T3 elapses, the resistance learning period T3 is set (at Step S32).
(3) Next, it is checked (at Step S33) whether or not the command current value ir is greater than or equal to 200 mA.
(4) Next, if the answer of the aforementioned Step S33 is YES, it is checked (at Step S34) whether or not the difference ie between the command current value ir and the feedback current value ifb is within a predetermined range, i.e., more than -20 mA and less than 20 mA.
(5) Next, if the answer of the aforementioned Step S34 is YES, the resistance value R of the linear solenoid is calculated according to the equation: output voltage value Vr/command current value ir (Step S35).
(6) Next, it is checked (at Step S36) whether or not the resistance value R calculated is below a resistance value R 0 , as stored in the memory unit 17.
(7) Next, if the answer of the aforementioned Step S36 is YES, the stored resistance value is adjusted (at Step S37) by the difference between the calculated resistance value R and the stored resistance value R 0 in a series of steps. In short, R 0 ←R 0 -α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(8) If the answer of the aforementioned Step S36 is NO, it is checked (at Step S38) whether or not the calculated resistance value R is over the resistance value R 0 , as stored in the memory unit 17.
(9) If the answer of the aforementioned Step S38 is YES, the stored resistance value is adjusted (at Step S39) by the difference between the calculated resistance value R and the stored resistance value R 0 . In short, R 0 ←R 0 +α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(10) Next, the learning period T3 is reduced (at Step S40). If the individual answers of the aforementioned Steps S31, S33, S34 and S38 are NO, the routine advances to the aforementioned Step S40.
FIG. 7 is a flow chart for setting the resistance learning period T3 of the linear solenoid of the present invention. The learning period is the length of time elapsed during correction of the resistance value.
(1) At first, it is checked (at Step S41) whether or not a predetermined time T2 (e.g., 30 sec) has elapsed after an engine start.
(2) If the answer of the aforementioned Step S41 is YES, the learning period T3 is set (at Step S42) to 1,000 milliseconds.
(3) If the answer of the aforementioned Step S41 is NO, the learning period is set (at Step S43) to 10 milliseconds.
Specifically in the state just after the engine start, it is usual that the oil temperature is frequently low so that the difference between the real resistance value and the resistance value in the memory unit is frequently large. If 30 sec has not elapsed, for example, after the engine start, the learning period is shortened so that the resistance in the memory unit may be able to approach the real resistance value quickly. If 30 sec elapses, on the other hand, the real resistance value and the resistance value in the memory unit become substantially equal, and the oil temperature is not abruptly changed to stabilize the resistance value. Considering the necessity for the learning and the stability of the current control, therefore, the learning period is elongated.
FIG. 8 is a current feedback waveform diagram of the case of the resistance learning of the present invention, and FIG. 9 is a current feedback waveform diagram of the case of no resistance learning of the prior art. Both of these Figures present waveforms of the case in which 1,200 mA is continuously outputted as the command current value.
It is apparent from FIG. 8 that the command current value can be quickly stabilized (to 1,200 mA, for example) for any oil temperature range by performing the resistance value learning control in conjunction with the current value comparison.
Without the resistance learning process of the present invention, prior art systems produce a control current that takes a stable normal value, as illustrated in FIG. 9, when the linear solenoid has a resistance value of 5 Ω (at an ordinary temperature of 80° C.). However, the control current highly overshoots the command current value of 1,200 mA when the linear solenoid has a resistance value of 3 Ω (at a cold run). When the linear solenoid has a resistance of 9 Ω (at an overheat time), on the other hand, the control current falls short of the command current value of 1,200 mA.
The resistance value learning control by the voltage value change is illustrated in FIG. 10.
(1) At first, it is checked (at Step S51) whether or not the resistance value learning period T3 of the linear solenoid has elapsed, that is, whether or not T3=0.
(2) Next, if the predetermined time T3 has elapsed, the resistance value learning period T3 of the linear solenoid is set (at Step S52).
(3) Next, it is checked (at Step S53) whether or not the command current value ir is greater than or equal to 200 mA.
(4) Next, if the answer of the aforementioned Step S53 is YES, it is checked (at Step S54) whether or not the output voltage value change is below a predetermined value for the preceding output voltage value.
(5) Next, if the answer of the aforementioned Step S54 is YES, the resistance value R of the linear solenoid is calculated according to the equation: output voltage value Vr/command current value ir (at Step S55).
(6) Next, it is checked (at Step S56) whether or not the calculated resistance value R is below the resistance value R 0 , as stored in the memory unit 17.
(7) Next, if the answer of the aforementioned Step S56 is YES, the learning is controlled (at Step S57) the difference between the calculated resistance value R and the stored resistance value R 0 . In short, R 0 ←R 0 -α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(8) If the answer of the aforementioned Step SS6 is NO, it is checked (at Step S58) whether or not the calculated resistance value R is over the resistance value R 0 , as stored in the memory unit 17.
(9) If the answer of the aforementioned Step S58 is YES, the learning is controlled (at Step S59) the difference between the calculated resistance value R and the stored resistance value R 0 . In short, R 0 ←R 0 +α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(10) Next, the learning period T3 is reduced (at Step S60). If the individual answers of the aforementioned Steps S51, S53, S54 and S58 are NO, the routine advances to the aforementioned Step S60.
The resistance value learning control by a timer is illustrated in FIG. 11.
(1) At first, it is checked (at Step S61) whether or not the resistance value learning period T3 of the linear solenoid has elapsed, that is, whether or not T3=0.
(2) Next, if the predetermined time T3 has elapsed, the resistance value learning period T3 of the linear solenoid is set (at Step S62).
(3) Next, it is checked (at Step S63) whether or not the command current value ir is greater than or equal to 200 mA.
(4) Next, if the answer of the aforementioned Step S63 is YES, it is checked (at Step S64) whether or not the command current value ir changes.
(5) Next, a time T4 is set (at Step S65) by the timer on the basis of the change in the command current value ir.
(6) Next, it is checked (at Step S66) whether or not the set time T4 has elapsed.
(7) If the answer of the aforementioned Step S66 is YES, the resistance value R of the linear solenoid is calculated according to the equation: output voltage value Vr/command current value ir (at Step S67).
(8) Next, it is checked (at Step S68) whether or not the calculated resistance value R is below the resistance value R 0 , as stored in the memory unit 17.
(9) Next, if the answer of the aforementioned Step S68 is YES, the learning is controlled (at Step S69) the difference between the calculated resistance value R and the stored resistance value R 0 . In short, R 0 ←R 0 -α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(10) If the answer of the aforementioned Step S68 is NO, it is checked (at Step S70) whether or not the calculated resistance value R is greater than the resistance value R 0 , as stored in the memory unit 17.
(11) If the answer of the aforementioned Step S70 is YES, the learning is controlled (at Step S71) the difference between the calculated resistance value R and the stored resistance value R 0 . In short, R 0 ←R 0 +α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(12) Next, the learning period T3 is reduced (at Step S72). Incidentally, if the individual answers of the aforementioned Steps S61, S63, S66 and S70 are NO, the routine advances to the aforementioned Step S72.
The resistance value learning control by an oil temperature detection is illustrated in FIG. 12.
(1) At first, it is checked (at Step S81) whether or not the resistance value learning period T3 has elapsed, that is, whether or not T3=0.
(2) Next, if the predetermined time T3 has elapsed, the resistance value learning period T3 is set (at Step S82).
(3) Next, it is checked (at Step S83) whether or not the command current value ir is greater than or equal to 200 mA.
(4) Next, if the answer of the aforementioned Step S83 is YES, the oil temperature and the resistance value of the linear solenoid are mapped in advance and stored in the memory unit 17 so that the resistance value R is determined (at Step S84) by retrieving the map.
(5) Next, it is checked (at Step S85) whether or not the resistance value R is less than the resistance value R 0 , as stored in the memory unit 17.
(6) Next, if the answer of the aforementioned Step S85 is YES, the learning is controlled (at Step S86) the difference between the calculated resistance value R and the stored resistance value R 0 . In short, R 0 ←R 0 -α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(7) If the answer of the aforementioned Step S85 is NO, it is checked (at Step S87) whether or not the calculated resistance value R is greater than the resistance value R 0 , as stored in the memory unit 17.
(8) If the answer of the aforementioned Step S87 is YES, the learning is controlled (at Step S88) the difference between the calculated resistance value R and the stored resistance value R 0 . In short, R 0 ←R 0 +α(R 0 -R). Here, the letter α indicates a coefficient, e.g., 1/4. Coefficient α is varied in order to make the correction large, when the difference between the calculated resistance value and the resistance value in the memory unit is large, and small when the difference is small. Therefore, the real resistance value can be quickly approached when the difference is large, and approached more gradually when the difference is small. When the difference is small, the correction of the resistance value is suppressed as much as possible to gradually reduce the difference so as to prevent disturbances from abrupt corrections of the resistance value, thus allowing stabilization of current output.
(9) Next, the learning period T3 is reduced (at Step S89).
If the individual answers of the aforementioned Steps S81, S83 and S87 are NO, the routine advances to the aforementioned Step S89.
Depending upon whether or not the difference between the modulator current command value and the monitor current value is within the predetermined range, as described above, it is possible to decide whether or not the resistance value of the linear solenoid can be calculated. However, this decision may also be made by another method using the change in the output voltage value or the timer.
Moreover, the oil temperature indicating the ambient temperature of the linear solenoid may be detected to learn the resistance value on the basis of the oil temperature.
In place of the oil temperature sensor, moreover, the resistance value may be learned on the basis of the engine water temperature although the accuracy is degraded.
The foregoing description of preferred embodiments 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. Obvious modifications or variations are possible in light of the above teachings. | A current control system for a linear solenoid for feedback-controlling an output voltage value on the basis of a difference between a command current value to the linear solenoid, as set according to a vehicle running state, and a feedback current value, as produced by monitoring a current value to be really fed to the linear solenoid, including: a decision circuit that decides whether or not the resistance value of the linear solenoid can be calculated; a real resistance value calculating circuit that calculates a real resistance value on the basis of a signal coming from the decision circuit, the command current value and the output voltage value; a comparison circuit that compares the calculated real resistance value and a resistance value in a memory unit; and a correction circuit that corrects the resistance value in the memory unit on the basis of the comparison result from the comparison circuit. The output voltage value is outputted on the basis of the corrected resistance value. | 5 |
CROSS-REFERENCE TO CO-PENDING APPLICATION
The present application is related to and claims priority to U.S. Provisional Application Ser. No. 60/065,794, filed Nov. 14, 1997. The contents of that provisional application are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to an improved plasma processing system, and particularly to a plasma processing system in which all surfaces of the system can be biased electrically and/or can be heated or cooled to improve the overall cleanliness of the system. The present invention can also control the wall coatings to be the proper amount to positively effect the process. The present invention also is directed to the process of cleaning such a processing system.
2. Description of the Background
High-density plasma processing systems are used for plasma etching and/or depositing thin films. Different parts of the plasma sources of the system are coated with condensable species generated during the plasma etching and deposition processes. The species deposited on various surfaces of the source affect the gas chemistry of the plasma source in various ways. For example, some deposits getter (i.e., remove from a gas) reactive species from the plasma, thus lowering etching and deposition rates. Other species on source surfaces, while they are condensable, also have high-enough vapor pressures that they can be desorbed from source surfaces, thereby changing the gas composition of the plasma. Gas species that adsorb on the wall are often radicals and polymerize with existing wall coatings to create species with must different vapor pressure and/or reactivity. Gas species that are condensed on the walls can also be crosslinked by electrons, ions or photon fluxes from the plasma to generate much different vapor pressure and/or reactivity species. Changes in the gas composition of the plasma by gettering, desorption of condensed species. or any other means, particularly in unregulated ways, results in loss of control of the of the total process. Herein, changes in the gas composition by any of these processes will be described generally as changes due to “wall contributions to process gas.”
Particle contamination has become an ever increasing problem as the complexity of integrated circuits increases and the feature size of these circuits decreases. Although clean-rooms had already greatly reduced contamination due to the ambient atmosphere by 1990, it was generally recognized by that time that processing tools and the processes themselves were major contributors of particle contamination. See Selwyn et al., Appl. Phys. Lett, 57 (18) 1876-8 (1990). Plasma processors had already been identified as major sources of contamination. See Selwyn et al., J. Vac. Sci. & Technol. A, 7 (4) 2758-65 (1989); Selwyn et al., 1990; Selwyn et al., J. Vac. Sci. & Technol. A, 9 (5) 2817-24 (1991(a)); and Selwyn, J. Vac. Sci. & Technol. A, 9 (6) 3487-92 (1991(b)). By 1990, suspended particles had been observed at the plasma/sheath boundary in plasmas used to etch, (see Selwyn et al., 1989), deposit (see Spears et al., IEEE Trans. Plasma Science, PS-14 (2) 179-87 (1986)) and sputter (see Jellum et al., J. Appl. Phys., 67 (10) 6490-6 (1990(a))). These suspended particles become negatively charged (see Wu, et al., J. Appl. Phys., 67 (2) 1051-4 (1990) and Nowlin, J. Vac. Sci. & Technol. A, 9 (5) 2825-33 (1991)) in the plasma and become trapped at the plasma/sheath boundary (Selwyn et al., 1990 and Carlile, Appl. Phys. Lett., 59 (10) 1167-9 (1991)).
When the plasma is extinguished, the particles may fall onto the wafer surface, thereby contaminating it. By 1992, it was believed that 70% to 80% of total wafer contamination was contributed by tools and processes used in device fabrication, and plasma processors are among the “dirtiest” tools in modern fab lines. See Selwyn, J. Vac. Sci. & Technol. A, 10 (4) 1053-9 ( 1 992).
Consequently, much attention has been directed to controlling particle generation in plasma processors and the cleaning of such reactors. However, the influence of process parameters and chamber design on both the reduction of wall deposits and in-situ reactor cleaning has been considered (see Vogt et al., Surface & Coatings Technol., 59 (1-3) 306-9 (1993)); and the control of particulate contamination by means of a self-cleaning tool design has been described (see Selwyn et al., 1992). The optimization of in-situ cleaning procedures using fluorinated reactive gases has recently been considered. See Sobelewski et al., J. Vac. Sci. & Technol. B, 16 (1) 173-82 (1998); Ino et al., Japanese J. Appl. Phys. 33 Pt. 1 (1B) 505-9 (1994) and Ino et al., IEEE Trans. on Semicon. Mfg., 9 (2) 230-40 (1996).
Yoneda (U.S. Pat. No. 4,430,547) describes an in-situ self-cleaning parallel plate plasma apparatus in which electrodes are heated by means of embedded resistive heaters or a circulating heated fluid. Benzing (U.S. Pat. No. 4,657,616) and Krucowski (U.S. Pat. No. 4,786,392) describe an inconvenient set of removable fixtures which must be placed inside the process chamber when cleaning becomes necessary and removed when cleaning has been completed. Benzing (U.S. Pat. No. 4,786,352) includes two or more electrodes on the exterior surface of a dielectric processor chamber, and, by applying an RF voltage between the two or more electrodes, establishes a plasma within the chamber for in-situ cleaning. Hayes (U.S. Pat. No. 4,795,880) uses the heating coil of a tube furnace as the inductive heating element by which a cleaning plasma is established within the tube. The cleaning is accomplished at furnace operating temperatures. Law (U.S. Pat. No. 4,960,488) describes a single-wafer processing chamber with the capability of a localized chamber self-etch and a wide area chamber self-etch. Both etches are possible due to the wide range of pressures at which the chamber may be operated and the variable electrode spacing. Aoi (U.S. Pat. No. 5,084,125) describes a processing chamber that has a processing section and a cleaning section. A movable wall is positioned alternately in the processing section and in the cleaning section. Neither chamber disassembly nor process interruption for cleaning is necessary. Moslehi (U.S. Pat. Nos. 5,252,178 and 5,464,499) describes a multi-zone and multielectrode plasma processing system. The apparatus permits activation of the multiple plasma electrodes in either a continuous or multiplexed format. Process gas flows may be stopped intermittently and a cleaning gas introduced so that an in-situ cleaning process occurs. Sekiya (U.S. Pat. No. 5,269,881) covers the interior surfaces of a parallel plate processing chamber with multiple conducting electrodes which are insulated from each other. A high frequency electric field is applied sequentially between the electrodes in various electrical configurations to achieve in-situ cleaning. Blalock (U.S. Pat. Nos. 5,514,246 and 5,647,913) describes an inductively coupled plasma reactor that includes a capacitive coupling electrode located between the exterior surface of the chamber wall and the induction coil used to excite the plasma. An RF field established between the capacitive coupling electrode and conductors within the chamber produces a cleaning plasma. Sandhu (U.S. Pat. Nos. 5,523,261 and 5,599,396) describes an inductively coupled plasma reactor in which a capacitive coupling electrode is used to facilitate cleaning as in Blalock. However, in contrast to Blalock, the electrode comprises a conducting liquid or a conducting polymer that fills a void between the inner and outer wall of the process chamber and is active only during chamber cleaning.
Grewal (U.S. Pat. Nos. 5,597,438) describes an etch chamber with three independently controlled electrodes. Both inductive and capacitive coupling are used. Usami (UK Patent Application No. 2,308,231) describes a capacitively excited reactor in which the counter electrode is not planar. It may be cleaned by exciting a cleaning plasma with the sample holder being either the powered or grounded electrode. In one embodiment, power at two frequencies is used during the cleaning procedure.
During plasma etching, etch rates vary in uncontrolled ways and a uniformity of etching can be greatly reduced in the presence of wall contribution to process gas. During plasma deposition, deposition rates, the composition of the deposited films, and the uniformity of film deposition are all affected in non-uniform and uncontrolled ways by wall contribution to process gas. Consequently, since the chemistry at surfaces in these sources was not controllable previously, the overall processes being implemented using the sources previously was uncontrolled. These changes in the wall contribution to process gas can change during the processing of a single wafer or over a longer time such generating changes from wafer to wafer.
Heating of the walls of deposition and etch process chambers during etching or deposition to minimize condensation is known. In deposition reactors heating surfaces hot enough to cause chemical reactions enhances the deposition rate of the material that one wishes to deposit, but heating to a temperature short of the chemical reaction threshold promotes desorption of effluents. However, heating all surfaces of a reactor while simultaneously bombarding them with plasma species form volatile compounds of the undesired wall absorbed species has not to our knowledge previously been described. Furthermore, it has not heretofore been possible in reactors that differ from the ESRF source.
Applied Materials, of Santa Clara, Calif. sells an etching reactor that uses fluorine chemistry and employs a heated silicon top plate to convert fluorine radicals (F*) to molecular fluorine (F 2 ) during the etching reactions, but not during cleaning of the reactor. Some other known systems have tried to control chemical changes on individual surfaces during processing, such as is disclosed in Japanese application 61-289634 entitled “Dry etching,” in which a polymer is prevented from being formed on an electrode by attaching alumina rings to an outer surface of the electrode; Japanese application 62-324404 entitled “Etching Device,” in which a hot water-based heater is attached to a silica chamber to improve etching performance; and Japanese application 63-165812 entitled “Etching Device,” in which an electrical heater is attached to a chamber to prevent reaction products from sticking to the surface. The contents of each of these applications is incorporated herein by reference. However, if only selected surfaces have controlled chemistries, then the remaining surfaces which are less reliably controlled control the overall introduction of wall contribution to process gas into their corresponding systems.
Still another problem with known systems is slow cleaning of surfaces within sources using plasma etching. In fact in many reactors the cleaning time significantly exceeds the process time, especially for thickly deposited materials. Such reactors are inherently very cost-ineffective.
Some known systems have utilized electrical biasing of individual components during cleaning, such as is disclosed in U.S. Pat. No. 5,269,881 to Sekiya et al., entitled “Plasma Processing Apparatus and Plasma Cleaning Method”, in which a high voltage is applied individually to each of three electrically isolated conductive blocks during cleaning; Japanese application 57-42131 entitled “Parallel Flat Board Type Dry Etching Device,” in which the polarity of an electrode is reversed between sputtering and cleaning; Japanese application 60-59739 entitled “Dry Cleaning Method,” in which a high frequency power is applied between a substrate electrode and a cleaning electrode to remove a silicon film; and
Japanese application 61-10239, entitled “Semiconductor Manufacturing Equipment,” in which the grounding self-bias of an anode plate is eliminated during a plasma etching/cleaning process. The contents of each of these applications is incorporated herein by reference. However, as described above in terms of controlling chemistry on surfaces, if only selected surfaces are cleaned, then the remaining surfaces which are less reliably cleaned control the overall uncleanliness of their corresponding systems.
SUMMARY OF THE INVENTION
It is a first object of the present invention to address at least one disadvantage of known plasma processing systems.
It is a second object of the present invention to provide a method for controlling the chemistry at all surfaces of a high-density plasma source.
It is a third object of the present invention to provide an improved method of cleaning a plasma processing system which reduces cleaning time of the plasma sources.
These objects and other objects of the invention are achieved by providing the capability to both regulate a temperature of and to electrically bias, each of the surfaces in the source. This regulation is enabled by using materials for all surfaces in the source which assist in controlling the chemical reactions that occur at each surface.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the attendant advantages thereof will become readily apparent with reference to the following detailed description, particularly when considered in conjunction with the accompanying drawings, in which:
FIG. 1A is a side view of a plasma processing chamber according to the present invention;
FIG. 1B is a top view of a plasma processing chamber according to the present invention;
FIG. 1C is a cross-sectional view of a plasma processing chamber according to the present invention where the cross-section has been cut from top to bottom;
FIG. 1D is a cross-sectional view of a plasma processing chamber according to the present invention where the cross-section has been cut parallel to the top and bottom of the chamber;
FIG. 1E is a cross-sectional view of a plasma process chamber including an RF power source and an inductive;
FIG. 2 is an expanded view of the wall of the process chamber circled in FIG. 1C;
FIG. 3A is a schematic illustration of a heating element surrounding the process chamber;
FIG. 3B is a sub-section of the heating element of FIG. 3A; and
FIG. 4 is a flowchart of the process of cleaning according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to the drawings in which like reference numerals designate identical or corresponding parts throughout the several views, FIG. 1A is a schematic illustration of a conical process chamber for processing substrates using a plasma. The process chamber may be substantially wider than tall and is illustrated with a portion of the exterior wall exposed to show the serpentine coils 110 of the heating element encased between the exterior wall and the interior wall. FIG. 1B illustrates the same process chamber from above with the exterior wall completely removed to show all the serpentine coils 110 of the heating element. The serpentine coils 110 are directly in contact with the chamber walls. The geometry of the heater is designed to cause the serpentine coils to go up and down the wall of the chamber in order to prevent significant circumferential current paths. This is important for preventing the heater element from shielding inductive RF power applied to the plasma. This process chamber is incorporated into an ESRF source as shown in FIG. 1 E.
FIG. 1C is a cross-sectional view of the process chamber and shows the exterior wall 100 and the interior wall 105 . The interior wall 105 can be made out of any dielectric material available in that shape. The shape need not be conical but can be domed, straight, cylinder, etc. Currently the preferred materials are fused quartz (SiO 2 ) and alumina (Al 2 O 3 ). Inside the process chamber is the plasma area 107 which is under vacuum. The process chamber also includes an electrostatic chuck 120 which connected to a heating and cooling device 125 to control the temperature of the chuck 120 . The heating and cooling device 125 can be a source of helium gas, which can be heated or cooled, and flows rapidly on the back side of the substrates during processing. For cleaning purposes, it is sufficient to have the helium simply provide thermal conduction between the substrate on chuck 120 . However, for processing, the chuck 120 is attached to an RF power coupling element 123 receiving RF power from an RF power source (not shown). Therefore, the chuck can be biased and/or temperature controlled during all operations. Similarly. capacitively-coupled RF power can be applied to a round gas injection plate (not shown) at the top of the chamber, and that plate can be outfitted with a heater. Thus, it can be cleaned and/or temperature controlled similarly to the interior wall 105 of the cylindrical part of the vessel or the chuck 120 .
FIG. 1D is a second cross-sectional view of the process chamber and shows the different components of the chamber sandwiched between the interior wall 105 and the exterior wall 110 . The serpentine coils 10 of the heating element 115 are between the interior wall 105 and the bias shield. The bias shield elements 130 of a slotted bias shield are controllably coupled to ground and an RF power source (not shown). These shield elements 130 are connected to ground when the plasma system is operating in the process mode. However, during cleaning when the bias shield elements 130 are connected to the RF power supply, RF power is coupled capacitively through the dielectric wall of the source which produces a pulsating negative DC bias on the interior wall 105 . This bias can be used to direct large quantities of reactive ions to the interior wall 105 . By careful selection of the gas species used, and hence the ion species used, virtually any condensate on the interior wall 105 can be removed.
In addition, electrostatic shield elements 135 are sandwiched between bias shield elements 130 and the exterior wall 100 . The electrostatic shield elements 135 , the bias shield elements 130 , and the serpentine coils 110 are all aligned as shown in order to minimize their effect on the induction plasma device fields. The bias shield elements 130 may also be immersed in a fluid that can be heated or cooled. If one wishes to promote desorption of condensates, the fluid can be heated. If, on the other hand, one wishes to promote inner wall reactions with ions, radicals or other species and/or to dissipate large amounts of power, the fluid can be cooled. The electrostatically-shielded radio frequency (ESRF) source. which is the subject of U.S. Pat. No. 5,234,529 issued Aug. 10, 1993 to Wayne L. Johnson (the inventor of the present application), is the only known high-density plasma source to which it is possible to add the capability to heat or cool and/or negatively bias all surfaces of the source. The contents of that patent are incorporated herein by reference.
Further electrostatic shield elements are disclosed in provisional applications entitled “Apparatus and Method for Adjusting Density Distribution of a Plasma,” Ser. No. 60/061,856, filed on Oct. 15, 1997; and “Apparatus and Method for Utilizing a Plasma Density Gradient to Produce a Flow of Particles, Ser. No. 60/061,857, filed on Oct. 15, 1997. The contents of these provisional applications are incorporated herein by reference. Also incorporated by reference are the corresponding PCT application filed on Oct. 15, 1998.
FIG. 2 is an expanded view of the circled section of the chamber wall of the process chamber as shown in FIG. 1 C. Plasma area 107 is in an interior of the elements of the process chamber wall and is shown for orientation. Each of the layers is described hereinafter starting from an interior of the process chamber. The expanded section includes a ceramic tube 140 with grooves in which the serpentine coils 110 are inlaid. The serpentine coils 110 are covered by a protective ceramic potting 145 . An organic thermal barrier 150 isolates the ceramic potting 145 and the heated chamber from an external dielectric cooling fluid 160 surrounding the inductive coil. The organic thermal barrier 150 must be resistant to the coolant. For example, a preferred cooling fluid 160 is fluorinert, so the barrier 150 must be a fluorinert-resistant material.
FIG. 3A shows the serpentine coils 110 of the heating element 115 as they would be configured if encircling the entire process chamber. The heating element can be split into a series of sub-elements—e.g., three sub-elements as shown in FIG. 3 B. These sub-elements can be used both during a processing step or during cleaning. This provides better matching to the power supply and better uniformity of heating. Typically each of the sub-elements would be identical. It is also important to fabricate the heating elements such that they have a high resistance for better thermal transfer. In addition, if a material is used that has a resistance that depends on temperature, then the temperature of the heating element can be easily determined by measuring the resistance of the heating element. The heating element can either be fabricated separately and placed into grooves as described above, or the heating element can be fabricated right onto the chamber using sputtered or an evaporated film. In either embodiment, it is important to be able to uniformly heat the process chamber.
Therefore, it can be seen that all internal surfaces of a plasma deposition or etching reactor can be temperature-controlled (hot or cold) and/or biased by capacitive coupling of RF power to the internal surfaces of the chamber. In no other known form of high density source (electron cyclotron resonance, helicon, transformer-coupled power, etc.) is this possible. In none of these cases can the power be capacitively coupled through the cylindrical walls of the process chambers to clean those regions. In some cases there are necessarily magnetic field coils that occupy the space that would have be to occupied by RF electrodes in order to couple power to the inner walls of the cylindrical chambers. In other cases the cylindrical walls of the chamber are metal (typically grounded) through which RF power cannot be coupled. For much the same reasons it is either not possible or exceptionally difficult to heat or cool the inner walls of the cylindrical parts of chambers of all but the ESRF high-density source. The uniqueness of the present invention in this regard is the combination of a dielectric wall, a biasable shield just inside the interior wall, and the fact that the outside surface of the wall can be easily heated or cooled. By using the internal heating element, a number of polymide wall contribution to process gas is reduced, thereby creating a cleaner process. A cleaner process results in less frequent maintenance.
The procedures for cleaning in both etch and deposition systems are basically the same. Of course the gases used will differ depending upon what material is to be removed from the internal surfaces. In general the procedure is given by the flowchart of FIG. 4 . In the first step of cleaning, a bias voltage is applied to the bias shield. The bias voltage employed should never be high enough to result in physical sputtering of the surfaces. Sputting redistributes wall species and when the wall is clean contaminates the chamber with wall material. All of the removal should occur chemically. Chemical cleaning means that the contamination species are removed from the chamber in the exhaust stream. This implies that the gas pressure used for cleaning should be high (>100 mTorr).
Secondly, all internal chamber surfaces should be heated to minimize recondensation. Further, the surfaces are heated to lessen the chance that condensate removed from one surface will redeposit on another surface. The law of conservation of filth states: “You cannot get anything clean without getting something else dirty; but you can get everything dirty without getting anything clean.” This is an application of that law.
Then the surfaces are actually cleaned. The order of cleaning is important. The largest surface should be cleaned first. Typically this is the interior wall 105 of the cylindrical vacuum vessel. Then the next largest surface is treated. Typically this is the gas injector plate. The cleaning process is continued with progressively smaller surfaces until all surfaces have been cleaned. This cycle may be iterated to improve cleaning precision. Typically the process ends when the substrate chuck has been cleaned.
Even with surface heating, recondensation may well occur in certain instances. In those cases, iterative cleaning of different surfaces may be necessary. If iterative cleaning is necessary, the same order should be followed—i.e., cleaning the surfaces from largest to smallest.
The materials of construction of the chamber wall and the gas injection plate are also important. For example, a fused quartz wall reacts with fluorine radicals and ions. If the reactive gas used in e.g. an etching process is F 2 , reactions of fluorine radicals or ions could change the gas chemistry. This may be desirable or undesirable. If it is undesirable, an alumina tube which will not react with fluorinated species should be used. The material is selected based on the desirability of chemical reactions occurring at the walls.
The control of chemistry at the walls is thought to be a combination of three effects: (1) catalytically-enhanced reactions; (2) bombardment by ions, radicals, energetic neutrals; and (3) adsorption by the wall material through pumping or gettering. Control of these effects can provide better control over the process as a whole.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A plasma processing system and method for producing a cleaner and more controlled environment for processing substrates such as semiconductor wafers. The plasma processing system includes a process chamber including an inner and an outer wall, a heating element thermally coupled to the inner wall of the process chamber, a bias shield, and an electrostatic shield. The processing system also includes an inductive coil surrounding the process chamber for coupling RF power to the gas inside the process chamber, thereby producing a plasma. RF power can also be applied to a wafer holder, such as an electrostatic chuck which can also be heated or cooled. The method of cleaning such a plasma processing system includes applying a bias voltage to the bias shield, heating the process chamber using the heater element, and cleaning the internal surfaces—starting with the largest surface and progressing to the smallest surface. | 8 |
This application is a 371 of PCT/SE05/01771 filed on 25 Nov. 2005
TECHNICAL FIELD
The present invention relates to a pulp mould for moulding three-dimensional pulp objects that can be used in a wide variety of applications. More specifically the objects are formed by using fibre slurry comprising a mixture of mainly fibres and liquid. The fibre slurry is arranged in the mould and part of the liquid is evacuated and a resulting fibrous object is produced.
BACKGROUND OF THE INVENTION
Packagings of moulded pulp are used in a wide variety of fields and provide an environmental friendly packaging solution that is biodegradable. Products from moulded pulp are often used as protective packagings for consumer goods like for instance cellular phones, computer equipment, DVD players as well as other electronic consumer goods and other products that need a packaging protection. Furthermore moulded pulp objects can be used in the food industry as hamburger shells, cups for liquid content, dinner plates etc. Moreover moulded pulp objects can be used to make up structural cores of lightweight sandwich panels or other lightweight load bearing structures. The shape of these products is often complicated and in many cases they have a short expected time presence in the market. Furthermore the production series may be of relative small size, why a low production cost of the pulp mould is an advantage, as also fast and cost effective way of manufacturing a mould. Another aspect is the internal structural strength of the products. Conventional pulp moulded objects have often been limited to packaging materials since they have had a competitive disadvantage in relation to products for example made of plastic. Moreover it would be advantageous to provide a moulded pulp object with a smooth surface structure.
In traditional pulp moulding lines, se for example U.S. Pat. No. 6,210,531, there is a fibre containing slurry which is supplied to a moulding die, e.g. by means of vacuum. The fibres are contained by a wire mesh applied on the moulding surface of the moulding die and some of the water is sucked away through the moulding die commonly by adding a vacuum source at the bottom of the mould. Thereafter the moulding die is gently pressed towards a complementary female part and at the end of the pressing the vacuum in the moulding die can be replaced by a gentle blow of air and at the same time a vacuum is applied at the complementary inversed shape, thereby enforcing a transfer of the moulded pulp object to the complementary female part. In the next step the moulded pulp object is transferred to a conveyor belt that transfers the moulded pulp object into an oven for drying. Before the final drying of the moulded pulp object the solid content (as defined by ISO 287) according to this conventional method is in around 15-20% and afterwards the solid content is increased to 90-95%. Since the solid content is fairly low before entering the oven, the product has a tendency of altering its shape and size due to shrinkage forces and furthermore structural tensions are preserved in the product. And since the shape and size has altered during the drying process it is often necessary to “after press” the product thereby enforcing the preferred shape and size. This however creates distortions and deformations deficiencies in the resulting product. Furthermore the drying process consumes high amounts of energy.
Conventional pulp moulds which are used in the above described process are commonly constructed by using a main body covered by a wire mesh for the moulding surface. The wire mesh prevents fibres to be sucked out through the mould, but letting the water passing out. The main body is traditionally constructed by joining aluminium blocks containing several drilled holes for water passage and thereby achieving the preferred shape. The wire mesh is commonly added to the main body by means of welding. This is however complicated, time consuming and costly. Furthermore the grid from the wire mesh as well as the welding spots is often apparent in the surface structure of the resulting product giving an undesirable roughness in the final product. Furthermore the method of applying the wire mesh sets restrictions of the complexity of shapes for the moulding die making it impossible to form certain configurations in the shape.
In EP0559490 and EP0559491 a pulp moulding die preferably comprising glass beads to form a porous structure is presented, which also mentions that sintered particles can be used. A supporting layer with particles having average sizes between 1-10 mm is covered by a moulding layer with particles having average sizes between 0.2-1.0 mm. The principle behind this known technology is to provide a layer wherein water can be kept by means of capillary attraction and by using the kept water to backwash the moulding die in order to prevent the fibres from clogging the moulding die. This process is however complicated.
U.S. Pat. No. 6,451,235 shows an apparatus and a method for forming pulp moulded objects using two steps. The first steps wet-forms a pre fibrous object which in the second step is heated and pressed under a large pressure. The pulp mould is formed of solid metal having drilled drainage channels to evacuate fluid.
U.S. Pat. No. 5,603,808 presents a pulp mould where one embodiment shows a porous base structure covered by a metal coating comprising squared openings of 0.1 mm to 2.0 mm.
U.S. Pat. No. 6,582,562 discloses a pulp mould capable of withstanding high temperature.
All prior art methods related to the production of a pulp mould, including the above disclosed methods, present some disadvantage.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a pulp mould that eliminates or at least minimizes some of the disadvantages mentioned above. This is achieved by presenting a pulp mould for moulding of objects from fibre pulp, comprising a sintered moulding surface and a permeable base structure where the moulding surface comprises at least one layer of sintered particles with an average diameter within the range 0.01-0.19 mm, preferably in the range 0.05-0.18 mm. This provides the advantage that the outermost layer of the moulding surface has fine structure with small pores in order to produce a pulp moulded object with a smooth surface and to contain fibres between a female and male mould preventing them from entering the same moulds and at the same time allowing fluid or vaporised fluid to emanate.
According to further aspects of the invention:
the pulp mould has a heat conductivity in the range of 1-1000 W/(m° C.), preferably at least 10 W/(m° C.), more preferred at least 40 W/(m° C.), which provide the advantage that heat can be transferred to the moulding surfaces during the press step in order for the press to be realised during increased temperature, which leads to a desirable vaporization of the fluid in pulp material. This vaporization helps the fluid to be sucked out throughout the moulds and helps the pressure to be equally distributed over the and thus the moulded pulp becomes equally pressurised. the permeable base structure comprises sintered particles having average diameters that is larger than the particles in the moulding surface, preferably of at least 0.25 mm, preferably at least 0.35 mm, more preferably at least 0.45 mm and having average diameters less than 10 mm, preferably less than 5 mm, more preferred less than 2 mm, which provides the advantages with a base structure having a high fluid permeability to enable fluid and vapour to be evacuated from the moulded pulp and a base structure having a high an internal strength as to withstand the pressure imposed on the base structure during the pressing steps. a permeable support layer comprising sintered particles is arranged between the base structure and the moulding surface where particles of the support layer have average diameter less than the average diameter of the sintered particles in the base structure and larger than the average diameter of the sintered particles in the moulding surface, which provides the advantages that support layer can minimize voids in the moulds safeguarding that the moulding surface does not collapse into the voids and if the size difference between the sintered particles of the base structure and the sintered particles of the moulding surface is very large, the support layer is added to create a smooth transition from the small particles of the moulding layer to the larger particles of the base structure and thus so by using a particle sizes in between these two extremes, which minimizes voids created between layers of different sizes. the pulp mould has a total porosity of at least 8%, preferably at least 12%, more preferred at least 15% and that the pulp mould has total porosity of less than 40%, preferably less than 35%, more preferred less than 30%, which provides the advantage that liquid and vaporised liquid can emanate from the pulp mould. a heat source is arranged to supply heat to the pulp mould, which provides the advantage that the can be heated during moulding. the bottom of the pulp mould is substantially flat and free of larger voids, arranged to transmit an applied pressure, which provides a surface suitable for heat transfer and provides the advantage of a form stable pulp mould. With larger voids is meant voids larger than the voids of the drainage channels, described below, for example a relief shaped pulp mould has a large void. a heat plate is arranged to the bottom of the mould and that the heat plate comprises suction openings, which provides the advantage that heat can be transferred to the pulp mould, thereby heating the moulding surface and that a source of suction can be arranged present a suction at the moulding surface. the pulp mould has at least one actuator arranged to its bottom, which provides the advantage that a female and a male pulp mould can be pressed together. the pulp mould is able to withstand temperature of at least 400° C., which provides the advantage that the mould can be heated to at least 400° C. during operation. the pulp mould contains at least one, preferably a plurality of drainage channels, which provides the advantage that drainage of fluid and vaporised fluid can be increased in the pulp mould. the drainage channel has a first diameter at the bottom of the pulp mould and a third diameter at the intersection between the base structure and the support layer, which is substantially smaller than the first diameter. the first diameter is larger than or equal to a second intermediate diameter and that the second diameter is larger than the third diameter. the second diameter is at least 1 mm, preferably at least 2 mm and that the third diameter is less than 500 μm, preferably less than 50 μm, more preferred less than 25 μm, most preferred less than 15 μm. the plurality of drainage channels are distributed in a distribution of at least 10 channels/m2, preferably 2 500-500 000 channels/m2, more preferred less than 40 000 channels/m2, providing the advantage of good drainage capabilities. at least one pulp mould is arranged on the heat plate and that the heat plate has suction openings and that the suction openings are arranged to mate the plurality of drainage channels. during operation a male and a female pulp mould are pressed into contact and the temperature of the moulding surface is at least 200° C. transmitting heat to a mixture of fibres and liquid arranged between the female and male pulp mould, which provides the advantage that a large part of the liquid is vaporised and due to the expansion of the vapour the vaporised liquid emanates through the porous pulp moulds. Complex shapes of the mould can be constructed due to the use of sintering technique in manufacturing the moulds. The pulp moulds can be constructed using graphite or stainless steel sintering moulds. These sintering moulds are easily manufactured using conventional methods and can produce very complex shapes at a low cost and short manufacture time. The sintered mould of the invention can be manufactured with great precision. The sintered mould of the invention can be used 500 000 times with preserved properties. The pulp mould may comprise one or more non-permeable surface areas containing said the sintered particles, the non-permeable surface area having a permeability that is substantially less than that of the moulding surface. If the sintered mould is outside the accuracy requirements it can be reformed by pressing the sintered mould in a second mould in which the sintered mould was created, without loss of characteristic features Surface structures on one or both sides of the pulp object can be created. For instance a logotype can be moulded at the bottom of a dinner plate. This can be done by adding a thin sintered layer with the shape of the logotype at one or both mouldings surfaces. A high internal strength in the resulting pulp moulded object can be produced using the pulp mould of the invention. Smooth surfaces on both sides are provided due to the fine accurate structure of the mouldings surfaces, combined with an ability to withstand high pressure and due to the heat conductivity making it possible to press using a high temperature at the moulding surfaces, enabling the liquid to be vaporised which will act as a cushion which smoothens any small inaccuracies in the moulding surfaces. Suction is evenly distributed due to the homogenous porosity of the mould. Pressure between the becomes evenly distributed due too the cushion effect of the steam expansion and the evenly suction.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following the invention will be described in relation to the appended figures, wherein:
FIG. 1 shows a cross sectional view of a male part and complementary female part of a pulp mould according to a preferred embodiment of the present invention in a separate position,
FIG. 2 shows the same as FIG. 1 but in an a moulding position,
FIG. 2 a shows a zooming of a part of FIG. 2 ,
FIG. 2 ′ shows a pulp mould in a moulding position according to a second embodiment of the invention,
FIG. 2 a ′ shows a zooming of a part of FIG. 2 ′,
FIG. 3 shows a single drainage channel,
FIG. 4 is a cross sectional zooming of the male part of the pulp mould of FIG. 1 showing the moulding surface the tips of three drainage channels and the upper part of the base structure,
FIG. 5 is a cross sectional zooming of the female part of the pulp mould of FIG. 2 showing the moulding surface the tips of two drainage channels and the upper part of the base structure,
FIG. 6 is a cross sectional zooming of the embodiment shown in FIG. 3 showing the moulding surface and the upper part of the base structure,
FIG. 7 is a cross sectional zooming of the embodiment shown in FIG. 4 showing the moulding surface and the upper part of the base structure,
FIG. 8 shows a part of the moulding surface of the female and male pulp mould as seen from the forming space,
FIG. 9 shows a three-dimensional drawing of a pulp mould according to the present invention, and
FIG. 10 is an exploded view of a preferred embodiment of a mould combined with a heat and vacuum suction tool according to the invention.
DETAILED DESCRIPTION
FIG. 1 shows a cross-sectional view of a male 100 and a complementary female 200 part of a pulp mould according to a preferred embodiment of the present invention. Both the female 200 and the male 100 part are constructed according to the same principles. A forming space 300 is arranged between the pulp moulds 100 , 200 , where the moulded pulp is formed during operation. A base structure 110 , 210 constitutes the main bodies of the pulp mould 100 , 200 . A support layer 120 , 220 is arranged upon the base structure 110 , 210 . A moulding surface 130 , 230 is arranged upon the support layer 120 , 220 . The moulding surface 130 , 230 encloses the forming space 300 . A source for heating 410 (see FIG. 10 ), a source for suction 420 using underpressure and at least one actuator (not shown) to press the female mould 200 and the male mould 100 against each other are arranged at the bottom 140 , 240 of the base structure 110 , 210 . It is advantageous that the pulp moulds 100 , 200 have good heat conductive properties in order to transfer heat to the 130 , 230 . It is advantageous that the base structure 110 , 210 is a stable structure being able to withstand high pressure (both applied pressure via the bottom 140 , 240 and pressure caused by steam formation within the mould) without deforming or collapsing and at the same time having throughput properties for liquid and vapour. More specific it is preferred that the throughput properties facilitate the drainage of liquid and vapour from the wet pulp mixture inside the forming space 300 during operation of the pulp mould 100 , 200 . It is therefore advantageous that the pulp mould has a total porosity of at least 8%, preferably at least 12%, more preferably at least 15% and at the same time to be able to withstand the operating pressure it is advantageous that the total porosity is less than 40%, preferably less than 35%, more preferably less than 30%. The total porosity is defined as the density of a porous structure divided by the density of a homogenous structure of the same volume and material as the porous structure. The throughput properties are increased by a plurality of drainage channels 150 , 250 . It is preferred that the plurality of drainage channels 150 , 250 are frusta conical and having a sharply pointed tip towards the intersection between base structure 110 , 210 and support layer 120 , 220 , e.g. the plurality of drainage channels 150 , 250 of the present embodiment has a nail form with the nail tip pointing towards the forming space 300 .
As is evident from FIG. 1 all parts of the mould 100 , 200 are applied with the fine particles that forms the support layer 130 , 230 . However, all parts of that surface are not used to form a pulp object, but there are peripheral surfaces 160 , 260 that will not be used to form a pulp object. As a consequence, these surfaces 160 , 260 preferably have a permeability that is substantially smaller than the 130 , 230 . In the preferred embodiment this is achieved by applying a thin impermeable layer 161 , 261 having appropriate properties, e.g. any kind of paint having sufficient strength durability to maintain its impermeable function when used under operating conditions (high heat some vibration, pressure, etc.). Alternatively this impermeable layer 161 , 261 may be achieved by workshop machining techniques, for instance by applying a high pressure upon these surfaces 160 , 260 , to achieve a compacted surface layer 160 , 260 whereby the pores will be closed. Of course other methods of making these surfaces 160 , 260 impermeable can be used as long as the result yields an impermeable surface 160 , 260 .
In FIGS. 2 , 2 a there is shown the position of the two mould halves 100 , 200 during the heat press forming action. As can be seen there is formed a forming space 300 between the mould surfaces 130 , 230 , that is about 0.8-1 mm., preferably in the range 0.5-2 mm. As can be the surfaces that will not be used to form a pulp object, 160 , 260 A has a thin impermeable layer 161 , 261 applied upon them. As can be seen in FIG. 2A the upper drainage channel 150 ends where the moulding surface 130 meets the forming space 300 and the lower drainage channel 250 ends between moulding-surface 230 and support layer 220 . The drainage channels 150 , 250 can have its pointed ending anywhere in the interval from the border between the base structure 110 , 210 and the support layer 120 , 220 till the border between the moulding surface 130 , 230 and the forming space 300 .
In this connection it may be mentioned that possible protruding fibre lumps, protruding on top of the slope 260 A, may easily also be handled by the use of applying a water stream, e.g. by means of an appropriately formed water jet, that will fold the protruding lumps onto the moulding surface 230 being under vacuum, such that they adhere to the rest of the fibres web.
In FIGS. 2 ′, 2 a ′ according to a second embodiment of the invention there is shown the position of the two mould halves 100 , 200 during the heat press forming action. As can be seen there is formed a forming space 300 between the mould surfaces 130 , 230 , that is about 1 mm., preferably in the range 0.5-2 mm. As also can be seen from FIG. 2 ′ the mating surfaces 161 , 261 of the mould halves 100 , 200 , do form a substantially smaller gap 300 ′ than the forming space 300 . The mating surfaces 161 , 261 is somewhat tilted to the left as is shown by the angle α in order to facilitate introduction of the male 100 into the female mould 200 . Also it can be seen that the bottom surface 140 of the male mould is above the level of the upper portion 260 A of the female mould, i.e. there is formed a gap between the support and heat plate 410 (see FIG. 10 ) of the male mould 100 and the female mould 200 , which is feasible thanks to the arrangement according to the inventive process where the applied pressure may be directly transferred to the pulp body, i.e. by means of the mould surfaces 130 , 230 . In other words normally there is no need for external abutting means (although they may be useful in some cases) to position the mould halves 100 , 200 during the pressing action. According to the embodiment shown in FIG. 2 ′ the design provides for using the relatively sharp edge between the horizontal surface 260 A and the vertical surface 261 to cut possible fibres lumps that protrude beyond the moulding surface 130 , 160 of the male mould 100 . As can be seen in FIG. 2 ′, 2 a ′ the plurality of drainage channels 150 , 250 is shown to end at the intersection between the moulding surface 130 , 230 and the forming space 300 . Depending of an actual embodiment of the invention the drainage channels 150 , 250 could have its pointed ending anywhere in the interval from the border between the base structure 110 , 210 and the support layer 120 , 220 till the border between the moulding surface 130 , 230 and the forming space 300 .
FIG. 3 shows a drainage channel 150 , 250 . The diameter Ø 1 is the diameter of the plurality of drainage channels 150 , 250 at the bottom 140 , 240 of the pulp moulds 100 , 200 . The main part 151 , 251 of the plurality of drainage channels 150 , 250 inclines slightly from the diameter Ø 1 towards the diameter Ø 2 . The relation between diameter Ø 1 and diameter Ø 2 is at least Ø 1 ≧Ø 2 and preferably Ø 1 >Ø 2 . Diameter Ø 2 is preferably above 2 mm, preferably 3 mm, i.e. preferably large enough to prevent capillary attraction. The form of the main portion t 1 of each drainage channel 150 , 250 is dependent of the thickness of the pulp mould 100 , 200 and therefore varies according to the desired shape of the pulp moulded object. The top portion t 2 of each drainage channel 150 , 250 has a diameter Ø 2 that preferably decreases sharply towards diameter Ø 3 , at the border between base structure 110 , 210 and support layer 120 , 220 . The diameter Ø 3 is preferably substantially zero and at least less than 500 μm preferably less than 50 μm, more preferably less than 25 μm, most preferably less than 15 μm. The relation between diameter Ø 2 and diameter Ø 3 is preferably Ø 2 >Ø 3 and most preferred Ø 2 >>Ø 3 . In the embodiment of FIG. 1 and FIG. 2 , Ø 2 was set to 3 mm, Ø 3 was set to 10 μm and the length t 2 of the top portion was set to 10 mm. If a drainage channel would have its tip in the border between the moulding surface 130 , 230 and the forming space 300 and meeting an inclination of the moulding surface 130 , 230 above 40° it may be an advantage to use a drainage channel 150 , 250 without a conical top, i.e. Ø 2 =Ø 3 , in order to ensure a pointed opening towards the forming space 300 . Another way to ensure a pointed opening towards the forming space 300 , when the moulding surface 130 , 230 has a steep inclination, is to increase the length t 2 of the top portion. If the drainage channels are arranged to have their tips in the border between the moulding surface 130 , 230 and the forming space 300 , the openings Ø 3 of the plurality of drainage channels 150 , 250 at the moulding surface 130 , 230 are preferably very small in order to prevent fibres contained in the forming space 300 from entering the pulp mould 100 , 200 , and also to produce a resulting surface structure of the pulp moulded object formed in the forming space 300 to be smooth. One of the reasons for the pointed tip of the plurality of drainage channels 150 , 250 is to prevent fluid from flowing back to the pulp moulded object after pressure and vacuum is released, due to the flow resistance created by the narrowing channel. Fibres from cellulose normally has an average length of 1-3 mm and an average diameter between 16-45 μm. Preferably the diameter of the drainage channels 150 , 250 increases gradually from the openings Ø 3 towards the diameter Ø 2 and further to the diameter Ø 1 of the drainage channels 150 , 250 . The plurality of drainage channels 150 , 250 of the embodiment of FIG. 1 and FIG. 2 was distributed with a distribution of 10 000 channels/m 2 . Normally the distribution is in the interval of 100-500000 and more preferred in the interval 2500-40000 channels/m 2 .
FIG. 4 and FIG. 5 are cross sectional zoomings of FIG. 1 and FIG. 2 respectively showing the moulding surface 130 , 230 , the support layer 120 , 220 , and the upper portion of the base structure 110 , 210 . As can be seen each drainage channel 150 , 250 penetrates the base structure 110 , 210 and has its pointed tip at the intersection between the base structure 110 , 210 and the support layer 120 , 220 . Depending of an actual embodiment of the invention the drainage channels 150 , 250 could have its pointed ending anywhere in the interval from the border between the base structure 110 , 210 and the support layer 120 , 220 till the border between the moulding surface 130 , 230 and the forming space 300 .
FIGS. 6 and 7 are cross sectional zoomings of FIG. 4 respectively FIG. 5 showing the moulding surface 130 , 230 , the support layer 120 , 220 and the upper part of the base structure 110 , 210 . As can be seen from the figures the moulding surface 130 , 230 comprises sintered particles 131 , 231 , having an average diameter 131 d , 231 d , provided in one thin layer. The thickness of the moulding surface is denoted by 133 , 233 and in the shown embodiment since the moulding surface 130 , 230 comprises one layer of particles the thickness 133 , 233 of the moulding surface 130 , 230 is equal to the average diameter 131 d , 231 d . Preferably sintered metal powder 131 , 231 with an average diameter 131 d , 231 d between 0.01-0.18 mm is used in the moulding surface 130 , 230 . (In the shown embodiment sintered metal powder 131 , 231 from Callo AB of the type Callo 25 was used to form the moulding surface 130 , 230 . This metal powder can be obtained from CALLO AB POPPELGATAN 15, 571 39 NÄSSJÖ, SWEDEN.) Callo 25 are spherical metal powder with a particle size range between 0.09-0.18 mm and a theoretical pore size of about 25 μm and a filter threshold of about 15 μm. As is evident for a skilled person in the field of powder metallurgy the particle size ranges includes smaller amounts of particles outside the ranges, i.e. up to 5-10% smaller respectively larger particles, this however has only marginal effects on the filtering process. The chemical composition of Callo 25 is 89% Cu and 11% Sn. As a way of example a sintered structure using Callo 25 and sintered to a density of 5.5 g/cm 3 and a porosity of 40 vol-%, would have about the following characteristics; tensile strength 3-4 kp/mm 2 , elongation 4%, coefficient of heat expansion 18·10 −6 , specific heat at 293 K is 335 J/(kg·K), maximum operative temperature in neutral atmosphere 400° C. Thus in the shown embodiment the thickness 133 , 233 of the moulding surface 130 , 230 is in the range 0.09-0.18 mm. Generally the moulding surface 130 , 230 comprises sintered particles 131 , 231 in at least one layer but most preferred in merely one layer. As can be seen from the figures the support layer 120 , 220 comprises sintered particles 121 , 221 , having an average diameter 121 d , 221 d.
The thickness of the support layer is denoted by 123 , 223 and in the shown embodiment, since the support layer 120 , 220 comprises one layer of particles, the thickness 123 , 223 of the support surface 120 , 220 is equal to the average diameter 121 d , 221 d . (In the shown embodiment sintered metal powder 121 , 221 from Callo AB of the type Callo 50 was used to form the support layer 120 , 220 . This metal powder can be obtained from CALLO AB POPPELGATAN 15, 571 39 NÄSSJÖ, SWEDEN.) Callo 50 are spherical metal powder with a particle size range between 0.18-0.25 mm and a theoretical pore size of about 50 μm and a filter threshold of about 25 μm. The chemical composition of Callo 50 is 89% Cu and 11% Sn. As a way of example a sintered structure using Callo 50 and sintered to a density of 5.5 g/cm 3 and a porosity of 40 vol-%, would have about the following characteristics; tensile strength 3-4 kp/mm 2 , elongation 4%, coefficient of heat expansion 18·10 −6 , specific heat at 293 K is 335 J/(kg·K), maximum operative temperature in neutral atmosphere 400° C. Thus in the shown embodiment the thickness 123 , 223 of the support layer 120 , 220 is in the range 0.18-0.25 mm. The support layer 120 , 220 may be omitted, especially if the size difference between the sintered particles 111 , 211 of the base structure 110 , 210 and the sintered particles 131 , 231 of the moulding surface 130 , 230 , is small enough, i.e. the function of the support layer 120 , 220 increase the strength of the mould, i.e. to safeguard that the moulding surface 130 , 230 does not collapse into the voids 114 , 214 , 124 , 224 . If the size difference between the sintered particles 111 , 211 of the base structure 110 , 210 and the sintered particles 131 , 231 of the moulding surface 130 , 230 , is very large, the support layer 120 , 220 can comprise several layers where the size of the sintered particles 121 , 221 gradually is increased in order to improve strength, i.e. to prevent structural collapse due to the voids between the layers.
The base structure 110 , 210 of the shown embodiment contains sintered metal powder 111 , 211 of the fabricate Callo 200 from the above mentioned Callo AB. Callo 200 is a spherical metal powder with a particle size range between 0.71-1.00 mm and a theoretical pore size of about 200 μm and a filter threshold of about 100 μm. The chemical composition of Callo 200 is 89% Cu and 11% Sn. As a way of example a sintered structure using Callo 200 and sintered to a density of 5.5 g/cm 3 and a porosity of 40 vol-%, would have about the following characteristics; tensile strength 3-4 kp/mm 2 , elongation 4%, coefficient of heat expansion 18·10 −6 , specific heat at 293 K is 335 J/(kg·K), maximum operative temperature in neutral atmosphere 400° C. The pores 112 , 212 of the base structure 110 , 210 in the first embodiment has thus a theoretical pore size 112 d , 212 d of 200 μm, enabling liquid and vapour to be evacuated through the pore structure.
FIG. 8 shows a part of the moulding surface 130 , 230 as seen from the forming space 300 . The moulding surface 130 , 230 comprises sintered particles 131 , 231 having an average diameter of 131 d , 231 d . The pores 132 , 232 of the moulding surface 130 , 230 have a theoretical pore size 132 d , 232 d . In the above described embodiment the theoretical pore size 132 d , 232 d is about 25 μm. The pores 132 , 232 are preferably small enough in order to prevent cellulose fibres from entering the interior of the pulp mould 100 , 200 , but at the same time enabling liquid and vapour to be evacuated through the pores 132 , 232 . Fibres from cellulose normally have an average length of 1-3 mm and an average diameter between 16-45 μm.
FIG. 9 shows a three-dimensional drawing of a pulp mould 100 , 200 according to the present invention. The bottom opening Ø 1 of the plurality of drainage channels 150 of the male mould 100 are shown in the drawing. A source for heating, a source for suction using underpressure and at least one actuator to press the female mould 200 and the male mould 100 against each other can be arranged at the bottom 140 , 240 of the base structure 110 , 210 . For instance a heated metal plate can be used to transfer heat to the flat bottom 140 , 240 .
FIG. 10 is an exploded view of the heat and vacuum suction tool 400 of a preferred embodiment. A plurality of male pulp moulds 100 are arranged upon a support and heat plate 410 . Of course the same heat and vacuum suction tool 400 can be used to attach female pulp moulds 200 . The support and heat plate 410 is heated by means of induction. The support and heat plate 410 is divided into a plurality of locations 411 , where in the preferred embodiment up to eight pulp moulds 100 , 200 can be placed side by side. Of course the invention is by no means limited to this number, but it is rather depending outside production factors outside the scope of the present invention, i.e. the surface area of the support and heat plate 410 can be increased or decreased and/or the bottom area of the pulp mould 100 , could likewise be increased or decreased. The support and heat plate 410 comprises a plurality of suction openings 412 which are connected to the vacuum chamber 420 . Each male pulp mould 100 have its bottom side 140 being substantially flat, as mentioned below this may be achieved by machining. A machining action of a sintered porous surface will make the pore openings to clog. Thanks to the drainage channels 150 that will have no negative effect on the process, since sufficient throughput surface is achieved by the drainage openings despite the clogging of the pores at the bottom 140 of the pulp moulds 100 . On the contrary it will be shown that this is rather an advantage in the present invention. The support and heat plate 410 comprises a plurality of suction openings 412 and these are preferably arranged to mate the openings Ø 1 of the plurality of drainage channels 150 at the bottom of the pulp mould 100 . Since the bottom area between the drainage channels 150 is meeting the solid part of the support and heat plate 410 , no suction would have occurred through the pore openings 112 at the bottom surface 140 in this embodiment. The clogging of the pores 112 at the bottom surface 140 presents an advantage due to the fact that this area is in contact with the solid part of support and heat plate 410 and hence heat is better transferred to the clogged machined bottom surface 140 and thereby to the pulp mould 100 . The same principles of above will naturally yield for a female mould 200 attached to the heat and vacuum suction tool 400 . The vacuum chamber 420 is arranged at the bottom of the support and heat plate 410 . A plurality of spatial elements 421 are arranged to support the heat plate 410 and prevent the support and heat plate 410 from bend deformations due to the negative pressure in the vacuum chamber 420 . An isolation plate 430 is arranged to the bottom of the vacuum chamber 420 . The task appointed for the isolations plate 430 is to prevent heat from the support and heat plate 410 to transfer further to the process equipment. The isolation plate is preferably made of a material with low heat conductivity. A cooling element 440 is constructed from a first 441 and second 442 cooling plate. In the bottom side of the first cooling plate 441 and the front side of the second cooling plate 442 there is formed a machined cooling channel 443 having channel openings 443 a , 443 b . A fluid can flow into the cooling channel 443 or out from the cooling channel 443 through the channel openings 443 a , 443 b . The cooling channel 443 is formed in a meandering pattern from the first channel opening 443 a towards the second channel opening 443 b . To the bottom of the cooling element 440 there is arranged a plurality of attach devices 450 . These plurality of attach devices 450 are used for attaching the heat and vacuum suction tool 400 to a pressing tool (not shown in the drawing).
According to a preferred embodiment the pulp mould is produced in the following manner. For the sintering process a basic mould (not shown) is used as is known per se, e.g. made of synthetic graphite or stainless steel. The use of graphite provides a certain advantage in some cases, since it is extremely form stable in varying temperature ranges, i.e. heat expansion is very limited. On the other hand stainless steel may be preferred in other cases, i.e. depending on the configuration of the mould, since stainless steel has a heat expansion that is similar to the heat expansion of the sintered body (e.g. if mainly comprising bronze) such that during the cooling (after sintering) the sintered body and the basic mould contracts substantially equally. In the basic mould there is formed a moulding face that corresponds to the moulding surface 130 , 230 and also non-forming surfaces 160 , 260 of the pulp mould (that is to be produced), which moulding face may be produced in many different ways known in the art, e.g. by the use of conventional machining techniques. Since a very smooth surface of the pulp mould is desirable the finish of the surface of the moulding face should preferably be of high quality. However, the precision, i.e. exact measurement, must not be extremely high, since an advantage with the invention is that high quality moulded pulp products may be achieved even if moderate tolerances are used for the configuration of the pulp mould. As described above, the first heat pressing action (when producing a moulded pulp product according to the invention), creates a kind of impulse impact within the fibre material trapped in the void 300 between the two mould halves 100 , 200 , that forces the free liquid out of the web in a homogeneous manner, despite possible variations of web thickness, which as a result provides a substantially even moisture content within the whole web. Hence it is possible to produce the basic moulds with tolerances that allow cost efficient machining.
For the actual production of the pulp mould 100 , 200 the whole portion of the formed surface of the basic mould is arranged with an even layer of the very fine particles, that will form the surface 130 , 230 ; 160 , 260 of the pulp mould, which is performed by providing a thin layer to the basic mould that will adhere the particles 131 , 231 of the surface layer 130 , 230 ; 160 , 260 . This may be achieved in many different ways, for instance by applying a thin sticky layer (e.g. wax, starch, etc.) on to the basic mould, e.g. by means of spray or by applying it with a cloth. Once the sticky layer has been applied an excessive amount of the fine particles 131 , 231 (which form the surface layer of the pulp mould) are poured into the mould. By movement of the basic mould, such that the excessive amount of particles 131 , 231 move around onto every part of the surface within the basic mould, it is accomplished to arrange an even layer of the fine particles 131 , 231 on each part of the surface in the basic mould. This process may be repeated to achieve further layers, for instance the support layers 120 , 220 . In the next stage pointed elongated elements, e.g. nails, which preferably have a slightly conical shape, are arranged on top of the last layer. These objects will form enlarged drainage passages 150 , 250 in the basic body, which will facilitate an efficient drainage of fluid from the pulp web and providing a flow resistance hindering fluid to pour back. Thereafter further particles 111 , 211 are poured into the basic mould forming the basic body 110 , 210 of the pulp mould, on the top of the surface layer 130 , 230 . Normally these further particles have a larger size than the particles in the surface layer. Preferably the bottom surface 140 , 240 of the pulp mould, i.e. the surface that is now directed upwardly, is evened out, before the entire basic mould is introduced into the sintering furnace, wherein the sintering is accomplished in accordance with conventional know how. After cooling, the sintered body 100 , 200 is thereafter taken out of the basic mould and the sharp pointed objects taken out from the body, which is especially easy if these are conical. (It may be preferred to apply the “nails” to a plate, which allows for introduction and removal of the “nails” in an efficient manner). Finally the rear surface of the pulp mould 140 , 240 preferably is machined in order to obtain a totally flat supporting surface. The provision of a flat surface leads to advantages, since firstly it facilitate exact positioning of the mould half 100 , 200 onto a supporting plate 410 , secondly it provides for transmitting the applied pressure evenly through the whole mould 100 , 200 and finally it provides a very good interface for transmitting heat, e.g. from the support plate 410 . However, it is understood that there is no need to always use a totally flat surfaces, but that in many cases the substantially plane surface that is achieved directly after the sintering is sufficient.
Moreover, some parts 160 , 260 of the surface 130 , 230 ; 160 , 260 are not used to form a pulp object, but there are peripheral surfaces 160 , 260 that will not be used to form a pulp object. As a consequence, these surfaces 160 , 260 are given a permeability that is substantially smaller than the 130 , 230 . As mentioned above, this may be achieved by applying a thin impermeable layer 161 , 261 having appropriate properties, e.g. any kind of paint having sufficient strength durability to maintain its impermeable function when used under operating conditions.
The pulp moulds 100 , 200 are operated by pressing the moulds 100 , 200 together so that the 130 , 230 face each other. In the forming space 300 between the moulding surface 130 , 230 a wet fibrous content is arranged on one of the moulding surfaces 130 , 230 , preferably by means of suction. The pulp moulds 100 , 200 can be heated during the pressing operation and the resulting temperature at the moulding surfaces is preferably above 200° C., most preferred around 220° C. By pressing the pulp moulds 100 , 200 quick with impulse pressing under high pressure and high temperature, large parts of the water in the fibrous content vaporises and the steam quickly expands and tries to escape the narrow area. The steam can evacuate the pulp moulds 100 , 200 by means of the porosity of moulding surface 130 , 230 , the support structure 120 , 220 , the base structure 110 , 210 and the plurality of drainage channels 130 , 230 .
Means of vacuum suction can further increase the evacuation speed and increase the amount of liquid and steam leaving the fibrous content. When the pulp moulds 100 , 200 again are separated from each other, the moulded pulp object which has been created from the fibrous content, is held to one of the 130 , 230 preferably by means of suction. Possibly also a gentle blow is applied through the opposite surface 230 , 130 at this moment to safeguard that the pulp object leaves with the desired mould half. When separating the pulp moulds 100 , 200 a negative pressure can occur in the forming space 300 , this negative pressure is far smaller than the pressing pressure. The conical endings of the plurality drainage channels 150 , 250 together with the small openings Ø 3 as well as the difference between the pore sizes 132 d , 232 d in the moulding surface 130 , 230 , the pore sizes 122 d , 222 d of the support layer 120 , 220 and the pore sizes 112 d , 212 d of the base structure 110 , 210 , functions as a flow resistance and restrain backflow to the forming space 300 , thereby restraining backflow to the fibrous content.
The invention is not limited by what is described above but may be varied within the scope of the appended claims.
Of course the configurations of the female 200 and male 100 moulds can differ from each other. The sintered particles 131 , 231 in the moulding surface 130 , 230 may differ in sizes, i.e. 131 d and 231 d may have different values. Likewise the sintered particles 121 , 221 in the support layer 120 , 220 may differ in sizes, i.e. 121 d and 221 d may have different values. Similarly the sintered particles 111 , 211 in the base structure 110 , 210 may differ in sizes, i.e. 111 d and 211 d may have different values. The thickness 133 , 233 of the moulding layer 130 , 230 preferably lies within 0.01 mm-1 mm and it is evident for the skilled person that the thickness 133 and the thickness 233 may differ from each other. The thicknesses of the support layer 123 , 223 may also differ from each other. It is also to be understood that in some embodiments the plurality of drainage channels 150 , 250 may be used in only one of the moulds 100 , 200 or in none of the moulds 100 , 200 . Also the spatial placement of the plurality of drainage channels 150 , 250 may differ between the moulds 100 , 200 as well as the size parameters Ø 1 , Ø 2 , Ø 3 , t 1 , t 2 and other shape characteristics of the plurality of drainage channels 150 , 250 . Obvious the distribution density of the plurality of drainage channels 150 , 250 may also differ between the female 200 and the male 100 mould. Furthermore the skilled person realises that the plurality of drainage channels 150 , 250 may differ in size and shape within an individual mould 100 , 200 . Furthermore the moulding surface 130 , 230 may comprise particles of different materials, shapes and sizes and may be divided into different segments, each segment comprising a certain particle type. Likewise the support layer 120 , 220 may comprise particles of different materials, shapes and sizes and may comprise different substantial layers, e.g. each substantial layer comprising a certain particle type. For instance the support layer 120 , 220 may comprise several layers where the size of the sintered particles 121 , 221 gradually is increased whit the smallest particles adjacent to the moulding surface 120 , 220 and the largest particles adjacent to the base structure 110 , 210 . Similar the base structure 110 , 210 may comprise particles of different materials, shapes and sizes and may be divided into different substantial layers comprising, e.g. each substantial layer comprising a certain particle type. The shape of the sintered particles of the base structure 110 , 210 , the support layer 120 , 220 and the moulding surface 130 , 230 may for example be spherical, irregular, short fibres or of other shapes. The material of the sintered particles may for example be bronze, nickel based alloys, titanium, copper based alloys, stainless steel etc. Furthermore it is to be understood that the shape of the mould 100 , 200 is decided by the wanted shape of the fibrous object and that the shape of the embodiments are by means of example. Since the pulp moulds 100 , 200 are produced using a sintering technique very complex shapes can be formed. For example a graphite form or a stainless steel form can be used for the sintering process and such a graphite form or stainless steel form can easily be manufactured in a workshop in complex shapes and with high accuracy. This makes it easy and cost effective to test alternative shapes for the fibrous object. Furthermore low production series of fibrous objects can be commercial possible due to the relative low cost of manufacturing a pulp mould 100 , 200 of the present invention. It is further to be understood that both pulp moulds 100 , 200 can be heated during operation as well as only one of the pulp moulds 100 , 200 as well as none of the pulp moulds 100 , 200 . The pulp moulds 100 , 200 can be heated in a wide variety of ways, a heated metal plate 410 can be attached to the bottom 140 , 240 of the pulp moulds 100 , 200 , hot air can be blown at the pulp mould 100 , 200 , heating elements can be added inside the base structure 110 , 210 , a gas flame can heat the pulp mould 100 , 200 , inductive heat may be applied, microwaves may be used, etc. Furthermore a vacuum source can be applied to the bottom 140 , 240 of both pulp moulds 100 , 200 , as well as to the bottom 140 , 240 of only one of the pulp moulds 100 , 200 , as well as to none of the pulp moulds 100 , 200 . Moreover the source of pressing the pulp mould 100 , 200 together can be imposed on both pulp moulds 100 , 200 or to only one of the pulp moulds 100 , 200 fixating the other pulp mould 200 , 100 . Furthermore merely one of the pulp moulds 100 , 200 could be used as a stand alone forming tool, to form a wet fibrous object in a conventional manner, i.e. normally by means of suction and thereafter normally dried in an oven, i.e. without any pressing steps. Furthermore the skilled man realises that the voids 114 , 214 , 124 , 224 can be filled with particles of appropriate sizes depending of the manufacturing technique used in creating the sintered pulp mould 100 , 200 . Moreover in some situations there might not be necessary to have an outermost layer having such small particles as the moulding surface 130 , 230 of the invention. It is to be understood that the pulp mould of the invention can be used without the moulding layer, i.e. the support layer 120 , 220 on top of the base structure 110 , 210 , as well as only the base structure 110 , 210 as the outermost layer. For instance in the forming step of the pulp moulding process, the pulp mould 100 , 200 may have larger particles in the outermost layer than in forthcoming pressing steps. Depending of an actual embodiment of the invention the drainage channels 150 , 250 could have its pointed opening Ø 3 anywhere in the interval from the border between the base structure 110 , 210 and the support layer 120 , 220 till the border between the moulding surface 130 , 230 and the forming space 300 . Moreover, using the support and heat plate 410 beneath the pulp mould 100 , 200 where the suction openings 412 are arranged to mate the bottom openings Ø 1 of the plurality of drainage channels 150 , 250 , it is obvious that it is preferred that the mating is a close match as possible and preferably every suction opening 412 always mate a corresponding bottom opening Ø 1 , but of course the invention is not limited to a perfect match rather the suction openings 412 could differ in diameters contra the bottom openings Ø 1 and the number of suction openings 412 could be larger as well as smaller than the corresponding bottom openings Ø 1 . Since the pulp mould 100 , 200 preferably are constructed by metal particles and since the pulp mould does not have a relief shape, i.e. the thickness of the pulp mould 100 , 200 is not constant following the contour of the pulp moulded object, but has preferably a flat bottom 140 resulting in that the thickness of the pulp mould 100 , 200 varies depending of the shape of the pulp moulded object, the pulp mould is able to withstand very high pressure without deforming or collapsing compared to a pulp 100 , 200 mould having a relief shape and/or comprised by a material of less strength, for instance glass beads. | This invention relates to a porous pulp mold comprising sintered particles and a plurality of drainage channels. The pulp mold of the invention can be produced in a fast and cost effective way. The molding surface of the invention comprises small pore openings, to evacuate fluid and prevent fibers from entering the pulp mold. Furthermore the pulp mold of the invention comprises drainage channels improving the drainage capabilities of the pulp mold. The molding surface can be heated to at least 200° C., due to high heat conductivity of the pulp mold and its ability to withstand high temperatures. | 3 |
RELATED APPLICATION
This application is a continuation of my copending application Ser. No. 567,840 filed Apr. 14, 1975, which was abandoned after the filing of this application.
BACKGROUND OF THE INVENTION
(a) Field of the invention
The present invention relates to program type electric shutters, and more particularly to a flash synchronization controlling means for program type electric shutters wherein the flash synchronizing action is made to be electronically controlled.
(B) Description of the prior art
There are program type electric shutters wherein the opening action of shutter blades is retarded so that the shutter blade opening characteristic curve may be made triangular and wherein the size of the opening of shutter blades is detected while the release button of the camera is pushed and the shutter is actually released so that the shutter blades may quickly open to a predetected opening position when the shutter is released and the shutter blade opening characteristic curve may be made trapezoid.
In this kind of program type electric shutter, anyhow, as the size of the opening formed by the shutter blades in photographing is automatically determined in response to the brightness of the object to be photographed in such case, in order to make the peak of the lighting of the flashing device coincide with the fully opened position of the blades, in the case of controlling the ignition time of the flashing device with a mechanical synchro-contact, the closing time of the synchro-contact must be moved in response to the size of the opening to be controlled. Therefore, in such system, there have been defects that the mechanical constitution is very complicated and that the synchronizing operation itself is unstable.
SUMMARY OF THE INVENTION
Therefore, a primary object of the present invention is to provide a flash synchronization controlling means for program type electric shutters wherein the flash synchronizing action is made to be electronically controlled so that the constitution of the entire means may be remarkably simplified and the flash synchronizing operation may be made very positively and stably.
According to the present invention, the above mentioned object is attained by connecting a second switching circuit for controlling the flash synchronization with a first switching circuit for controlling the closing time of shutter blades and by making the switching operation of the second switching circuit take place earlier by a predetermined time than the switching operation of the first switching circuit so that, however the size of the opening of the shutter blades may vary, the flashing device may ignite prior by the predetermined time to the closing time of the shutter blades.
These and other objects of the present invention will become more apparent during the course of the following detailed description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram showing a flash synchronization controlling means embodying the present invention;
FIG. 2 is a plan view of an essential part of a shutter mechanism to which the flash synchronization controlling means shown in FIG. 1 is to be applied;
FIG. 3 is an explanatory diagram showing the operation characteristics of the circuit shown in FIG. 1; and
FIG. 4 is a circuit diagram showing another embodiment of the flash synchronization controlling means according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First of all, in FIG. 1, reference symbol E represents a current source, symbol S 1 represents a current source switch, symbol Rx represents a photoconductive element, symbol C 1 represents a condenser, symbol S 2 represents a switch for starting a delaying action, symbol T 1 represents a transistor for making a constant current having the value determined in accordance with the resistance value of the photoconductive element Rx flow to the condenser C 1 , symbols T 2 and T 3 represent transistors forming a differential amplifier, symbol R K represents a potentiometer for adjusting the voltage between the base and emitter of the transistor T 3 , symbol T 4 represents an amplifying transistor, symbol M represents an electromagnet for controlling the closing operation of the shutter blades, and symbols D 1 and D 2 represents diodes for compensating voltages. The above mentioned elements constitute the same electric shutter circuit as the well known one. The above mentioned transistors T 2 and T 3 form a first switching circuit for controlling the closing time of the shutter blades. Symbol Ra represents a variable resistor connected in the above mentioned constant current circuit. Symbols T 5 and T 6 represent transistors forming a differential amplifier. The base of the transistor T 5 is connected to the above mentioned potentiometer R K and the voltage between the base and emitter of the transistor T 5 is associated with the voltage between the base and emitter of the above mentioned transistor T 3 so as to be kept at the same potential. Further, the base of the transistor T 6 is connected to one end of the above mentioned variable resistor Ra. Symbol T 7 represents a transistor. Symbol L represents a flash bulb. Symbol SCR represents a rectifying element with a controlling electrode attached to it corresponding to a conventional mechanical synchro-contact. Symbol C 2 represents a main condenser. Symbol Z represents a D.C. - D.C. converter. The above mentioned rectifying element SCR, main condenser C 2 , converter Z and flash bulb L form a flashing device. The transistors T 5 and T 6 form a second switching circuit for controlling the flash synchronization.
FIG. 2 shows an example of shutter blade opening and closing mechanism utilizing the above described electric shutter circuit. Its constitution shall be explained in the following. Reference numeral 1 represents a setting lever having an arm 1a, hook portion 1b, cam portion 1c and gear portion 1d, supported rotatably by a shaft 2 and biased counterclockwise by a spring 3. Numeral 4 represents a release lever having a hook portion 4a engageable with the hook portion 1b of the setting lever 1, supported rotatably by a shaft 5 and biased counterclockwise by a spring 6. Numeral 7 represents a shutter blade opening and closing member having pins 7a and 7b, having a gear portion 7c formed, supported rotatably by the shaft 2 and biased clockwise by a spring 8. In such case, the tension of the spring 8 should be so selected as to be smaller than the tension of the spring 3. Numerals 9 and 10 represent shutter blades having slots 9a and 10a respectively formed and supported rotatably respectively by pins 11 and 12 fixed to a base plate not illustrated. The slots 9a and 10a are both fitted to the pin 7b on the shutter blade opening and closing member 7. The movement of the shutter blades 9 and 10 is operatively connected also with a diaphragm means F arranged in front of the photoconductive element Rx as is briefly shown in FIG. 1. Numeral 13 represents an electromagnet corresponding to the electromagnet M in FIG. 1. Numeral 14 represents a magnet lever having an armature 14a facing the pole of the electromagnet 13 (M) rockably supported on one arm thereof and a shaft 14b erected on the other arm and rotatably supported by a fixed shaft 15. Numeral 16 represents a flywheel having a pinion 16a integrally formed and supported rotatably by the shaft 14b. The pinion 16a can mesh with both of the gear portion 1d of the setting lever 1 and the gear portion 7c of the shutter blade opening and closing member 7. Numeral 17 represents a holding lever having pins 17a and 17b respectively on both arms, supported rotatably by a fixed shaft 18 and biased clockwise by a spring 19. The pin 17a is engaged with the cam portion 1c of the setting lever 1 and the pin 17b is arranged in such position that the magnet lever 14 may be rotated counterclockwise by the clockwise rotating force of the holding lever 17. Numeral 20 represents a spring connected between the arm of magnet lever 14 on which the armature 14a is supported the arm of holding lever 17 on which the pin 17b is erected. Numeral 21 represents a stopper for restricting the counterclockwise rotation of the setting lever 1.
By the way, the movable contact piece of the current source switch S 1 is in contact with the release lever 4 and is so arranged that, when the release lever 4 is rotated clockwise, said switch S 1 may be closed. Also, the movable contact piece of the starting switch S 2 is engaged with the pin 7a of the blade opening and closing member 7 so that, when said member 7 is rotated counterclockwise, said switch S 2 may be opened.
The operation of the above mentioned means shall be explained in the following.
The illustrated state represents the cocked state of the shutter. When the release lever 4 is rotated clockwise from this state by the operation of a release button not illustrated, first the current source switch S 1 will be closed, then the hook portion 1b and hook portion 4a will be disengaged from each other and the setting lever 1 will begin to be rotated counterclockwise by the spring 3. At the same time, the pinion 16a will be rotated clockwise and therefore the shutter blade opening and closing member 7 meshed with the pinion 16a will also begin to rotate counterclockwise integrally with the lever 1. In such case, by governor means effected by the action of the flywheel 16 and spring 8 the shutter blade opening and closing member 7 will be rotated at a comparatively low speed. On the other hand, the counterclockwise rotation of the shutter blade opening and closing member 7, and hence pin 7a, will cause the starting switch S 2 to open. With the opening of switch S2, an electric current Ix of the magnitude determined by to the resistance value of the photoconductive element Rx in response to the brightness of the objects to be photographed will flow to the condenser C 1 . In such case, as shown in FIG. 3, the potential of the point Q (FIG. 1) will rise as in the curve a due to the charge with the constant current but the potential of the point P (FIG. 1) biased by IxRa by the presence of the variable resistor Ra will rise as in the curve a'. Therefore, the potential of the point P will reach a predetermined value V K , which is to the base bias of the transistors T 3 and T 5 as set by the potentiometer R K prior to the potential at point Q reaching value V K . When the current source switch S 1 is closed and the switch S 2 is initially opened, the condition of the circuit is such that transistor T 2 is off, and transistors T 3 and T 4 on, such that electromagnet 13 (M) is energized. Further, transistor T 5 is on and transistors T 6 and T 7 off such that rectifying element SCR is non-conductive and flash bulb L remains unlighted. As noted above the setting lever 1 rotates counterclockwise, at this point in the operation, under the tension of spring 3. As setting lever 1 rotates counterclockwise, cam portion 1c and pin 17a will be disengaged from each other and the holding lever 17 will be rotated clockwise by the spring 19. However, at this time, the armature 14a will be attracted by the electromagnet 13 (M) and therefore said lever 14 will be held in the illustrated position. By the counterclockwise movement of the shutter blade opening and closing member 7, the shutter blades 9 and 10 will open an exposure aperture and the film not illustrated will be exposed. As noted above, the potential at point P rises in accordance with curve a' ultimately attaining value V K . At this point, when the potential of the point P reaches V K , the transistor T 5 will turn off, the transistor T 6 will turn on, turning on transistor T 7 , such that rectifying element SCR is rendered conductive to cause flash bulb L to flash. The rectifying element SCR with a controlling electrode attached to it will be on and the flash bulb L will be lighted to flash.
As noted above, and as will hereinafter be more fully explained, the potential at point Q reaches value V K a predetermined time interval after point P. When the potential of the point Q reaches V K after such predetermined time delay, the transistor T 2 will turn on, the transistor T 3 will turn off, turning off transistor T 4 to de-energize the electromagnet 13 (M). When the electromagnet 13 (M) is thus de-energized, the magnet lever 14 will be rotated counterclockwise by the holding lever 17 under the tension of spring 19. At this time, the pinion 16a will be disengaged from the gear portion 1d of the setting lever 1 and the gear portion 7c of the shutter blade opening and closing member 7. Shutter blade opening and closing member 7, previously rotated counterclockwise due to the tension of the spring 3 overcoming the tension of the spring 8, will be quickly rotated clockwise by the action of the spring 8 once no longer held to setting lever 1 by pinion 16a. Therefore, at this time, the shutter blades 9 and 10 will turn from the opening action to the closing action and will quickly close the exposure aperture to end the exposure of the film. By the way, in case the brightness of the object to be photographed is different from that in the above described case and the rising rate of the potential of the point Q is as in the curve represented by the symbol b in FIG. 3, the rising rate of the potential of the point P will be as in the curve represented by the symbol b'.
As described above, according to the present means, before the shutter blades 9 and 10 turn from the opening action to the closing action, that is, before said blades 9 and 10 form a diaphragm aperture determined by the resistance value of the photoconductive element Rx and the capacitance value of the condenser C 1 , the flash bulb L will be lighted. This timing shall be discussed in the following. Now, if the magnitude of the electric current to charge the condenser C 1 is made Ix, the time Tx until the potential of the point Q reaches V K from zero will be Tx = V K /KIx (wherein K is a constant). Further, the time Tx' until the potential of the point P reaches V K will be Tx' = (V K - IxRa)/KIx. The time difference Td between Tx and Tx' will be Td = Tx - Tx' = Ra/K. This fact means that the time difference Td can be set by selecting the value of the variable resistor Ra independently of the current value Ix. Thus, by properly setting the value of the variable resistor Ra by considering the lighting characteristic of the flash bulb L, the peak of the lighting can be made to coincide exactly with the fully opened position of the shutter blades.
Another embodiment shall be explained with reference to FIG. 4 in the following. In this embodiment, the same respective symbols are attached to the elements acting the same as in FIG. 1. Symbol Dx represents a photoelectric element, symbol Rf represents a resistor, symbols S 3 and S 5 represent change-over switches, symbols T 8 and T 9 represent field effect transistors forming a differential amplifier, symbols T 10 and T 11 represent transistors, Rv represents a resistor, symbol C 3 represents a condenser for memory, symbol S 4 represents a switch and symbols T 12 and T 13 represent field effect transistors forming a differential amplifier. By the way, the collector of the transistor T 7 is connected to the control electrode of rectifying element SCR (not shown) in the same manner as in FIG. 1. In this embodiment, the transistor T 8 and T 9 form a first switching circuit and the transistor T 12 and T 13 form a second switching circuit. The shutter blade opening and closing mechanism to which this electric shutter circuit is to be applied is, for example, of a type wherein a set of shutter blades used also as diaphragm blades is used to operate so that, until the release button of the camera is pushed and then the shutter is released, an opening size controlling member may be moved at a constant speed and a CR circuit for determining the opening size of the shutter blades may be operated as synchronized with the beginning of the movement of said controlling member. When the potential of the condenser in said CR circuit reaches a potential corresponding to the magnitude of the photoelectric current generated in photoelectric element Dx, the movement of the above mentioned controlling member and the operation of the CR circuit may be stopped, then the shutter blades may be opened to a size corresponding to the stopping position of the above mentioned opening size controlling member and an exposure time controlling delay circuit including the above mentioned photoelectric element may be operated. When the potential of a condenser in said exposure time controlling delay circuit corresponds to the memory potential of the condenser in the above mentioned opening size controlling CR circuit, the shutter blades may be closed. This type of shutter blade opening and closing mechanism is disclosed in detail, for example, in U.S. Application Ser. No. 523,120, entitled "An electric shutter", and filed on Nov. 12, 1974, in the name of Kunio MATSUMOTO, now U.S. Pat. No. 3,953,865. Therefore, its detailed explanation shall be omitted here.
Now, the operation of this embodiment shall be explained. First of all, by the camera release operation, a release actuating member will be disengaged and will begin to move at a constant speed. In such case, the change-over switches S 3 and S 5 will be in the positions illustrated with solid lines. When the current source switch S 1 is closed with the beginning of the movement of the release actuating member, an electric current Ix corresponding to the voltage generated in the photoelectric element Dx in response to the brightness of the object to be photographed will flow between the emitter and collector of the transistor T 1 , as a result, the gate of the transistor T 8 will be biased by the current Ix, the transistor T 8 will be on, the transistor T 9 will be off, the transistor T 10 will be off and the transistor T 11 will be on. On the other hand, the above described opening size controlling member will move following the movement of the release actuating member and the switch S 4 will be opened as synchronized with it. Therefore, the condenser C 3 will be charged through the resistor Rv and the collector and emitter of the transistor T 11 . When the charging potential Vx of the condenser C 3 reaches the gate potential of the transistor T 8 , the transistor T 8 will turn off, the transistor T 9 will turn on, the transistor T 10 will be on and the transistor T 11 will be off. When the transistor T 10 is on, the electromagnet M will be energized, the following movement of the opening size controlling member will be stopped by the energization and the shutter blade closing operation controlling member will be held. On the other hand, when the transistor T 11 is off, the charging to the condenser C 3 will stop. The charging potential of this condenser C 3 will be memorized as a base bias of the transistors T 9 and T 12 and this potential Vx corresponds to V K of the embodiment in FIG. 1. In the final stage of the movement of the release actuating member, the change-over switches S 3 and S 5 will be switched to the positions shown with the dotted lines in FIG. 4 and the shutter will be released. As a result, the shutter blades will quickly open to the position determined by the opening size controlling member and the switch S 2 will be opened as operatively connected with its opening operation. The exposure time at this time will be determined by the time until the potential of the point Q reaches the memory potential Vx of the condenser C 3 but the potential of the point P will reach the memory potential Vx still prior to the potential of the point Q and therefore the flashing device will be ignited in the same relation as in the preceding embodiment. As apparent from the above description, the potentiometer R k and the capacitor C 3 are used as a standard voltage setting circuit means for the first and second switching circuits.
By the way, the type of the exposure time control delaying operation is not limited to the constant current charging type. Further, in the embodiment in FIG. 1, in order to obtain the time difference Td, the variable resistor Ra is provided. However, instead of providing this variable resistor Ra, the time difference Td can be made to be obtained by setting the base potential of the transistor T 5 to be lower by a predetermined value than the base potential by connecting the base of the transistor T 5 with another potentiometer or making the base potentials of the transistors T 3 and T 5 separately settable as by changing the relative position of the two slides of potentiometer R K .
Further, the present means has been explained by taking a flash bulb as an example of the flashing device but can be applied also to the case of using a strobodischarge lamp and can be also utilized for the purpose of correcting the guide number.
The shutter blade opening and closing mechanism is not limited to the type in which the shutter blades are also diaphragm blades but may be of a type in which opening blades and closing blades are separately provided. Further, the present means can be applied also to a type in which shutter blades are steppedly opened instead of the type in which a delaying device is made to act on the opening stroke of shutter blades.
Further, it can be applied also to a shutter of a type in which, in FIG. 1, the photoconductive element Rx is replaced with a variable resistor and, in FIG. 2, the photoelectric element Dx is excluded, the resistor Rf is replaced with a variable resistor and the variable resistor is operatively connected with a photographing distance adjusting member so that the diaphragm aperture (opening size) may be automatically adjusted in response to the photographing distance at the time of flash photographing. | A flash synchronization controlling circuit for program type electric shutters. A first switching circuit is utilized for controlling the shutter closing and a second switching circuit is connected to the first switching circuit and utilized for controlling the flash actuation in order that the flash synchronization controlling circuit may be simplified and to provide a very positive and stable flash synchronizing operation. The flash synchronization controlling circuit is arranged so that the switching operation of the second switching circuit can be effected earlier by a predetermined time interval than that of the first switching circuit. | 6 |
This application is a continuation-in-part of U.S. patent application Ser. No. 07/815,959, filed Jan. 2, 1992, now matured into U.S. Pat. No. 5,284,274.
FIELD OF THE INVENTION
This invention relates to toys designed to be carried and used by children engaged in action play. More particularly, this invention relates to new action toy weapons which enable a child to produce and direct a liquid stream from a toy in ways which uniquely resemble the operation of real weaponry.
BACKGROUND OF THE INVENTION
Squirt guns and other toys for producing water streams have been available in the marketplace for many years. These toys typically include an internal refillable reservoir for holding a small quantity of water. The reservoir is drawn upon, as needed, to eject or "squirt" the water from the toy until the reservoir is exhausted.
Such prior art toys do not resemble real weapons in their operation which detracts from the realism and play value of the toys. Also, repeatedly refilling the small water reservoirs in such toys is cumbersome and detracts from the fun of using the toys.
SUMMARY OF THE INVENTION
Accordingly, it is an object of this invention to provide an action toy system which operates in a fashion uniquely resembling real weapons.
It is a further object of the invention to provide an action toy system including prefilled shell-like capsules which may be loaded into and ejected from a toy weapon or other play device.
It is another object of the present invention to provide a toy weapon or other play device which will accept a multiplicity of capsules prefilled with water for ejection of the water from successive capsules either directly from the capsules or indirectly through the toy weapon or other play device.
It is yet another object of the present invention to provide readily filled and readily replaceable capsules which can be used in lieu of the internal water reservoir of conventional squirt gum.
A still further object of the present invention is to provide a toy weapon or other play device having a spring-loaded mechanism for emptying a water reservoir.
Another object of the present invention is to provide a toy weapon or other play device having a mechanism for emptying a water reservoir in a single operation.
It is a further object of the present invention to provide convenient and practical methods for filling capsules to be used in squirt guns and other play devices designed to produce water streams.
A yet further object of the present invention is to provide action toys which eject water and incorporate more than one type of weapon play.
It is a further object of the present invention to provide a single toy weapon or other play device which may be used to alternatively produce a water stream or to propel an object.
Still a further object of the present invention is to provide action toys in the form of shotguns, rifles, missile launchers, and bow and arrows.
These and other objects of the present invention will become apparent to those skilled in the art upon consideration of the accompanying specification, claims and drawings.
In one important embodiment, the present invention entails an action toy system employing a removable capsule for containing a liquid, such as water, which is ejected through a toy gun, missile launcher or other toy such as a tank, a cannon or a jet fighter when the capsule is mounted in the toy and the toy is triggered. Although the capsule, as described below, is designed for repeated refilling, it is contemplated that single use, prefilled capsules could be used in the practice of the present invention. Thus, when the child decides to use the toy weapon, he pulls a trigger mechanism to drive the water either directly from the capsule or into the appropriate passages of the "weapon" from which it is either directly or indirectly ejected.
In another important embodiment, the present invention comprises a toy weapon, illustrated below in the form of missile launcher, wherein a water-filled capsule is mounted to the front of the unit and the water is driven directly from the orifice of the capsule to the target upon release of a cocked spring within the unit. In yet another embodiment of the invention, a combination toy "weapon" is provided comprising, for example, a toy shot gun which accepts a plurality of prefilled capsules in combination with an automatic rifle having its own water reservoir, from which water is "shot" upon activation of the rifle trigger, or from which water may be continuously squirted from the shotgun in a pump-action fashion.
Another significant embodiment of the invention comprises a crossbow system which operates somewhat like a conventional crossbow, storing energy in a spring which is cocked by pulling back on the bow. In this system, however, when the bow is released, a stream of water rather than an arrow shoots from the weapon.
In a further embodiment of the invention, a toy weapon, illustrated below in the form of a crossbow, is provided with a double feature nozzle which can alternatively produce a water stream or propel an object. The object may be made of a light, resilient material like foamed polyethylene and formed into the shape, e.g., of an arrow or a missile.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and advantages, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the several figures, and in which:
FIGS. 1, 2 and 3 are perspective views of a toy shotgun constructed in accordance with the present invention, in the hands of a child first loading a shell-like water-filled capsule into the gun and then operating the gun;
FIGS. 4A and 4D respectively illustrate, in elevation, capsules used in the toy shotgun of FIGS. 1-3, before filling and after filling, and FIGS. 4B and 4C respectively illustrate, in plan view, an apparatus used in filling the capsules;
FIG. 5A is a elevation view of an alternate embodiment of the capsule of FIG. 4A and FIG. 5B is a perspective view illustrating a procedure for filling the capsule of FIG. 5A;
FIGS. 6A and 6C are, respectively, elevation views of yet another alterative embodiment of the capsule of the invention in empty and filled states and FIG. 6B is a perspective view illustrating a procedure for filling the capsule;
FIG. 7 is a partial elevation view of the toy shotgun of FIG. 1, which has been cut away to show certain internal features of the toy and FIG. 7A is an enlarged fragmentary view of one of those details;
FIGS. 8, 9, 10, and 11 are further partial elevation views of the toy shotgun of FIG. 1, cut away to reveal selected internal features;
FIG. 12 is a partially cut-away elevation view of a toy missile launcher comprising an alternate design of the present invention;
FIG. 13 is a perspective view illustrating a missile capsule, intended for use with the missile launcher of FIG. 12, being filled with water;
FIG. 14 is a partially cut-away elevation view of the launcher unit of the embodiment of FIG. 12 highlighting the cocking mechanism of the device and FIGS. 14A and 14B are enlarged perspective views of two key components of that cocking mechanism;
FIGS. 15-17 are partially cut-away elevation views of the missile launcher illustrated in FIGS. 12-14, showing the operation of the toy weapon;
FIG. 18 is a partially cut-away elevation view of a combination shotgun/rifle toy in accordance with the invention;
FIG. 19 is an enlarged view of the pump mechanism of the rifle of the combination toy weapon of FIG. 18;
FIG. 20 is a side elevation view of a combination bullet action/pump action toy weapon in accordance with the invention;
FIG. 21 is a partial, cut-away view showing the manner in which the reservoir of the toy weapon of FIG. 20 is filled;
FIG. 22 is a cut-away side elevation view of the toy weapon of FIG. 20;
FIG. 23 is a partial, cut-away top view of the center portion of the toy weapon of FIG. 20;
FIGS. 24, 24A and 25 are partial, cut-away elevation views of the capsule filling reservoir of the toy weapon of FIG. 20;
FIG. 26 is a partially cut-away elevation view of a crossbow toy in accordance with the invention and FIG. 26A is an enlarged cut-away view of the one-way valve of the crossbow toy of FIG. 26;
FIG. 27 is a partial, enlarged cut-away view of the shaft locking mechanism of the toy of FIG. 26;
FIGS. 28 and 29 are partial, cut-away views of an alternative double feature nozzle design intended to replace the nozzle in the crossbow toy of FIG. 26; and
FIG. 30 is an alternative, futuristic crossbow toy in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning first to FIGS. 1-3, there is illustrated, in the hands 11 of a child, a toy pump-action shotgun 10 having a barrel 12, a slide handle 14 and a trigger 16. The shotgun includes a receiver 18 having a loading gate 20 and a breechblock 22. In FIG. 1, a prefilled capsule of water in the shape of shotgun shell 24 is shown being inserted into the loading gate of the toy shotgun.
Once the appropriate number of shell capsules have been loaded into the shotgun, slide handle 14 is drawn back, as shown in FIG. 2, cocking the shotgun for action in the manner described below. When the child wishes to fire the weapon by ejecting the water from a capsule, he merely pulls back on trigger 16 which produces water stream 28, as depicted in FIG. 3. The first capsule is then automatically ejected from the breechblock as slide handle 14 is drawn back for the next shot, and the second capsule moves into place, ready for firing.
Shell capsule 24 is illustrated in FIG. 4A. Capsule 24 comprises a barrel portion 30 open at its top end 32 and having a central orifice 34 at its bottom end 36. A plunger 38 is freely longitudinally moveable in the barrel portion of the capsule. The plunger comprises a stopper 40 with rubber "O" rings 42 which sealingly engage the inner wall 44 of the barrel portion. In FIG. 4A, the capsule is shown in its empty condition; in FIG. 4D it is shown in its loaded condition, after filling with water 46, as explained below.
FIGS. 4B and 4C illustrate an apparatus 26 for filling capsule 24. The apparatus includes a water container 52 having a circular collar 54, shown in cross-section, for receiving the capsule, and a pin 56 located on the central axis of the collar in line with orifice 34 of the capsule. Thus, an empty capsule may be filled by placing it upon the pin, with the pin engaged in the orifice, and pushing down, causing plunger 38 to move from bottom 36 to top 32 of the capsule, while drawing water 46 from container 52 into the capsule body. The capsule is then removed from the collar, ready for loading into the toy shotgun. In a preferred embodiment, to prevent leakage from the filled capsule, the clearance between orifice 34 and pin 56 will be about 0.5 mm to 1.0 mm, and the diameter of the orifice will be less than about 2.5 min.
In FIGS. 5A-5B and 6A-6C, alternative designs of a refillable capsule are illustrated. Thus, in FIG. 5A a two-part syringe-type capsule 102 is illustrated which includes a shell 104, shown in cross-section, and a solid plunger portion 106 having rubber "O" rings 108 to seal against the inner surface of the shell. The shell includes an orifice 110. This shell is filled by simply submerging orifice 110 in water (FIG. 5B) and pulling back upon the plunger to draw the water into the shell. Orifice 110 must be kept small enough to prevent air from entering the capsule to displace the water and cause leakage.
In FIGS. 6A-6C, a bellows-type capsule 112 is illustrated, including a rigid portion 114, a bellows portion 116 and an orifice 118. In order to fill this shell, the bellows are compressed and, as shown in FIG. 6B, the orifice is submerged in water, and the bellows are permitted to expand to draw the water 46 into the capsule, as depicted in FIG. 6C. The sizes and shapes of the capsules of FIGS. 4, 5 and 6 and the corresponding sizes and shapes of the various components of the shotgun which receive and manipulate the capsules will be readily chosen by those skilled in the art.
The internal operating mechanism of shotgun 10 is illustrated in FIGS. 7-11. Thus, in FIG. 7, a series of four water-filled shell capsules 24A-24D are shown resting in magazine tube 58. The capsules are held snugly in place between a compressed spring 60 and a backstop 62, shown in enlarged form in FIG. 7A.
When slide handle 14 is drawn back, the upwardly projecting proximal nub 50 on link arm 26 (FIG. 8) which is attached to the slide handle and rests against catch 64 of plunger control 66, draws plunger 68 against proximal spring 70, to compress the spring. Spring 70 is locked in its compressed state by catch 72 which ramps over the catch 64 and snaps into place as illustrated in FIG. 9, while the continuing movement of the plunger carries latch housing 74 rearwardly to compress distal spring 76 as well. The slide handle is then moved forward to its "ready" position, permitting latch housing 74 to move forward under the force of the expanding distal spring 76 to engage the first capsule 24a which has been moved into position during the operation of the slide handle, as described below in connection with FIG. 10.
In FIG. 10, latch housing 74 is shown engaged with capsule 24A under the pressure produced by distal spring 76. As trigger 16 is squeezed, it pivots release lever 78 upwardly to engage catch 72 at A, releasing plunger control 66 and driving plunger 68 against capsule plunger 38 under the force stored in proximal spring 70, thereby forcing water 46 from the capsule through orifice 34, and past chamber orifice 79 into an intermediate chamber 80 (FIG. 11) in communication with the bore 82 in shotgun barrel 12 through which the water is directed to produce a forceful and sustained stream of water 28 (FIG. 3). Chamber 80 holds the first shot of water to insure that a stream of water will emerge from the shotgun with the engagement of every capsule except the first. Intermediate wall 83, spring 84 and pin 86 together act as a one-way valve so that water can enter chamber 80 by force from the capsule but will not escape.
The movement of fresh capsules into the breechblock is illustrated in FIG. 11. As shown there, the rearward movement of link arm 26 compresses springs 70 and 76 releasing the pressure of latch housing 74 against the capsule thereby permitting the spent capsule to be pushed from the chamber under the force of the next entering capsule. As the backward motion of the link arm continues, lever 88 of load arm 87 is rocked downwardly at B under the force of distal nub 90 of link arm 26. This pivots the proximal arm 92 of the lever upwardly to engage the load arm lever at C and to pivot it about axis 96, moving the load arm carriage 98 downwardly to receive the next capsule which is moved into place under the action of spring 60 (FIG. 7). As link arm 26 is then returned to its forward position, spring 100 causes the load arm lever carriage to pivot back to its resting position with the capsule in breechblock 22 engaged by latch housing 74, and ready for firing.
Another embodiment of the invention is illustrated in FIGS. 12-17. In this embodiment, the toy weapon is a missile launcher. Thus, missile launcher 200, as illustrated in FIG. 12, includes a water-filled missile capsule 202 and a launcher unit 204 with sight 205. The water-filled missile capsule includes a housing 206 having a water reservoir 208 and an orifice 210. A plunger 212 is provided in the missile capsule, including a pair of resilient tings 214 for sealingly engaging the inner cylindrical surface of the water reservoir.
The features and operation of this embodiment of the invention may be best understood by examining the loading, cocking, and firing of the toy missile launcher which proceeds as follows:
A. In FIG. 13, missile capsule 202 is shown being loaded by submerging orifice 210 in water 46 and pulling up upon the control arm 213 of plunger 212, to draw the water into reservoir 208. (See FIG. 12.)
B. Turning now to launcher unit 204, spring 214 is shown in FIG. 14 in its relaxed position, with interlocking plungers 216 and 218 ready to receive a water-filled missile capsule. Thus, as capsule 202 is inserted into the barrel 220 of the weapon, control arm 213 of plunger 212 pushes front plunger 216 to the rear through plunger 218 until the radially protruding lip 224 of the front plunger engages the rear plunger and presses it up against spring 214, whereupon the missile is rotated by the child into a locked position in a conventional bayonet mount 221.
C. Handle 226 is then pulled back, as shown in FIGS. 15 and 16, engaging the rear pawl 228 of rear plunger 218 to compress or load spring 214. This rearward movement of the handle brings front pawl 230 of the rear plunger into engagement with the rear arm of trigger lever 232 which, as it snaps into place as shown in FIG. 16, indicates that spring 214 is fully loaded. At the same time, lips 224 of spring arms 225 of the front plunger 216 (FIG. 14A) engage slots 236 of the rear plunger (FIG. 14B) to lock the front plunger firmly in place. Handle 226 is then returned to its forward position leaving spring 214 fully cocked with trigger 240 engaging the front arm of trigger lever 232.
D. When trigger 240 is pulled, trigger lever 232 is pivoted downwardly at D, as illustrated in FIG. 17, thereby releasing rear plunger 218. Spring 214 then drives plungers 216 and 218 and control arm 213 of the missile plunger forward to force water 208 through nozzle 210 of the missile capsule.
E. When the missile capsule is empty, the child rotates it to unlock the bayonet mount and he or she replaces it with another prefilled missile.
Turning now to FIGS. 18 and 19, there is illustrated a combination toy comprising toy shotgun 250 using prefilled capsules 24a, 24b and 24c, as described above, and an automatic rifle 252 with a water reservoir 254 which can be filled by conventional means and clipped into place as shown.
Automatic rifle 252 includes a nozzle 256, a tube 258, a pump unit 260, a gear box 262, and a motor 266. Batteries 268 for running the motor are held in a pistol grip 270. Thus, as seen in FIG. 19, automatic rifle 252 is operated by pressing trigger 264 to activate motor 266 driving tapered pinion 276 on the shaft 274 of the motor which rotates in a counterclockwise direction causing gear 272 to rotate in a clockwise direction. Shaft 278, which is connected to piston shaft 280, converts this rotating action into linear movement. Thus, when piston shaft 280 is pulled to the right of pump unit 260, and steel ball 281 caps opening 282, a vacuum is created in the chamber 284 of the pump. Accordingly, the water inside reservoir 254 will be drawn into the pump chamber through hose 286, opening the input valve (steel ball 288). When piston shaft 280 is pushed forward, steel ball 288 closes off opening 210 to prevent water from returning to the reservoir while pushing the other ball 281 up to opening 282 to permit the water to be driven through hose 292 and out of nozzle 256.
Alternatively, the child may operate the toy in the shotgun or "capsule" mode, by loading water filled capsules into the shotgun portion 250 of the weapon, as described above in connection with FIGS. 1-11, and then pressing trigger 220 to drive the water from successive capsules, which are ejected from the toy when spent.
In FIG. 20, yet another embodiment of the invention is illustrated comprising a combination water-filled bullet capsule system and a pump action squirt gun. In this embodiment, illustrated and described in greater detail below in connection with FIGS. 21-25, a control lever 302 is positioned on the side of the weapon 300 to select the choice of play, i.e. bullet action or pump action. A water reservoir 304 is located in the gun stock 306. There is a transparent slot 308 located next to water cap 310 to indicate the level of the water in the reservoir. A filling valve (FIG. 21) is also provided, covered by water cap 310, for both filling the reservoir through a water tap and for filling individual capsules from the reservoir.
This combination toy weapon is operated as follows:
A. Open water cap 310, fill reservoir 304 (FIG. 21), and close cap.
B. Move control lever 302 to bullet action position.
C. Open water cap 310 and push empty bullet capsules 24 one by one into the valve to fill them with water, as illustrated in FIG. 24.
D. Close water cap 310 and load the water-filled capsules into magazine 312 (FIG. 22).
E. Insert magazine 312 (loaded with water-filled capsules 24a-24e) into the body of the weapon and lock in place with lock lever 314.
F. Pull slide handle 316 to the rear (left in FIG. 22) until a click is heard and then return it to its forward position.
G. Pull trigger 318 to shoot. The water stream emerges from nozzle 320 to travel a substantial shooting distance. In one embodiment, the shooting distance is 28 feet, and the reservoir contains 580 cc of water. If all proximately 7.5 cc of water is used in each shot, this reservoir will provide 77 shots of bullet play or pump action play.
H. As slide handle 316 is again moved rearwardly, the now empty bullet capsule 24a is ejected through the opening and a click sound is heard again after which the handle is returned to its forward position in preparation for the second shot. This procedure is repeated for each shot.
I. After the last bullet capsule (24e) in the magazine is ejected, the slide handle automatically locks in its forward position. There is one more shot which may be triggered before the child either takes the magazine out of the weapon to reload the water-filled bullets for another round of bullet action play or the child changes over to pump action play.
J. In order to change the play mode to pump action (at any time), control lever 302 (FIG. 20) is moved to the forward pump action position, disabling trigger 318 and thereby halting all bullet action. The slide handle is then moved backwardly and released, returning automatically to its forward position as a water stream emerges from nozzle 320. The stream may be made continuous by pumping the slide handle until reservoir 304 is exhausted.
The above features are provided by a single pump mechanism which produces both the bullet action play and the pump action play. In order to obtain this dual function from a single pump mechanism, the water which appears to be ejected from the nozzle in the bullet action play mode actually has already been emptied from the capsule into the water reservoir by the operation of the slide handle to be drawn out and ejected by the pump mechanism which draws the water from the water reservoir through a connecting tube.
The details of the mechanism of the above dual mode toy weapon are illustrated in FIGS. 22 and 23. Control lever 302 is permanently fixed to an internal trigger box 322. By pushing the control lever to bullet action position, trigger box 322 is moved out of the way to prevent contact with the levers for pump action play, as more fully described below.
When magazine 312 is inserted into the gun body, the bullet capsules in the magazine push arm 324 to the right, turning lever 326 out, to raise the right side of lock lever 328 upwardly, freeing up slide handle 316. If, however, there was no bullet capsule in the magazine, lever 326 would be pivoted downwardly by spring 330 and the right side of the slide handle would drop to the original lower position to prevent the slide handle from moving backwardly until a bullet-filled magazine is loaded into the gun or the play mode is changed to pump action play.
Now, as slide handle 316 is pulled back, connecting arm 332 pushes piston shaft 334 and its resilient piston 335 to the rear drawing water into chamber 336 from reservoir 304 through hose 338. As illustrated in FIG. 23 this pulling action moves metal shaft 340, connected to arm 332 and bullet plunger 333, forcing the bullet plunger back so that hook 336 in the front part of the bullet plunger may eject the empty capsule from the weapon and admit a fresh water-filled capsule. When end tip 337 of piston shaft 334 is hooked by trigger lever 341, spring 342 will have already been fully cocked. By returning the slide handle to the forward position, bullet capsule plunger 333 is pulled forwardly, to hold the water-filled bullet in place. The return action causes shaft 344 to drive the water inside the bullet out of the valve 346 and into the reservoir 304 through hose 348.
When trigger 318 is pulled to fire the bullet action weapon, it pushes trigger lever 341 upwardly so that its other end moves downwardly, releasing piston shaft 323. Spring 342 then pushes the piston shaft forward to drive water out through nozzle 320, which is shown with an optional, conventional one-way valve 343 to prevent water leakage. This procedure is repeated for following shots, after each of which the empty bullet capsule is ejected and the next water-filled bullet capsule is pushed up by part 350 and spring 352 to replace the spent capsule.
When the action mode is changed to pump action, trigger box 322 is moved forward to alter the following three mechanical actions:
I. Portion 322A pushes trigger lever 341 away from the hooking and triggering position, enabling piston shaft 334 to move back and forth freely.
II. Portion 322B of trigger box 322 forces front end lever 328 downwardly, while its right side is pivoted upwardly to permit the front end to move back and forth freely.
III. Portion 322C of the trigger box locks plunger hook 336, preventing bullet ejection. Slide handle 316 and piston shaft 220 are now free to move, for continuous pumping operation without touching trigger 318.
The water filling mechanism of the device combines the filling of the reservoir with the capability of filling individual capsules from that reservoir. The mechanism insures that the bullet capsules can always be filled to capacity even when the water in the reservoir becomes low. This is illustrated in FIGS. 24 and 25.
Thus, when cap 310 is opened, cylinder 360 will be pushed upwardly by spring 362. The water in the reservoir flows down through holes 365 in cylinder 367. Cylinder 360 is then pushed down as a bullet capsule is inserted into it forcing the water in cylinder 367 to flow up into cylinder 360 through holes 364 in cylinder 360 thereby causing the water level in cylinder 360 to rise to a volume equal to the volume in one bullet capsule. As the capsule is then pushed down, shaft 366 pushes the capsule stopper 40 upwardly to extract water from the reservoir. Thus, even if the water in the reservoir is low, the bullet will be filled.
Next, a crossbow toy is illustrated in FIG. 26. In order to operate crossbow 400, arrow handle 402 is pulled back by the child against a spring force presented at points A & B. This action also moves shaft 403 and piston 404 backwardly, drawing water from reservoir 406 (closed off by cap 408) into chamber 417 through one-way valve 414 and tube 401. One-way valve 414, which is shown in enlarged form in FIG. 26A, includes a membrane 426 which opens and closes across passage 428 to permit water to be drawn from the reservoir while preventing backflow. The pulling of the arrow handle cocks spring 416, which may be immediately released to empty the reservoir in a single operation or locked in its cocked state. Locking in the cocked state may be accomplished with the structure of FIG. 27 which would be located at C in FIG. 26. In this embodiment handle 402 is adapted to be twisted to the right or to the left, to rotate shaft 403 45° in either direction so that rib 420 in the shaft engages one of stoppers 422 and 424 thereby locking the entire mechanism. Thus, when the child is ready to fire the locked, cocked crossbow, handle 402 is returned to the middle position and released. Thus, when the handle is released, whether from a locked, cocked position or not, spring 4 16 will push shaft 403 and piston 404 forward to force the water out of the bow through valve 416 and nozzle 418. Valve 426 serves as a one-way valve to prevent water leakage from the nozzle. Finally, the bow arms may be folded for easy storage and packaging.
In an alternative embodiment of the present invention which may be employed with any of the above-described action toys, a double feature nozzle is employed to produce a water stream or to propel an object. This alternative embodiment is illustrated in FIGS. 28 and 29, in the form of an elongated nozzle 418A which replaces nozzle 418 in FIG. 26.
As illustrated in FIG. 28, double feature nozzle 418A has a tubular outer surface 500 and a rounded tip 502 with a longitudinal passage 504 in communication with chamber 417 (FIG. 26). A water stream 506 is shown emerging from the tip.
Turning now to FIG. 29, a lightweight resilient arrow-shaped object 508 having an internal tubular internal cavity 510 is shown mounted to the double feature nozzle. The object may, of course, be made in any shape, although a generally aerodynamic shape is preferred. The object may be made of any lightweight material such as, for example, foamed polyethylene. Also, the internal tubular cavity 510 should have resilient walls and a diameter less than that of the nozzle so that the walls seal against the outer surface of the nozzle. Thus, in one design, a 2.5 inch long nozzle with an external diameter of 0.280 inches was found to work well with an extruded, foamed polyethylene arrow having a 2.6 inch long internal tubular cavity with a diameter of 0.274 inches. Object 508 may be mounted to nozzle 418A whether or not reservoir 406 and chamber 417 contain water, although it is preferred that the reservoir and chamber be empty. When the object is mounted to the nozzle and the crossbow is cocked and released as described above, the air or water pressure produced at the nozzle will propel the object forward as shown in outline form in FIG. 29.
Finally, a futuristic crossbow 600 is illustrated in FIG. 30. This crossbow operates in the same fashion as that illustrated in FIG. 26 and therefore its features have been labelled with identifying numbers:used in FIG. 26. Futuristic crossbow 600 does not include a mechanism for locking spring 416 (FIG. 27). Accordingly, this embodiment will empty upon release of the handle.
While the present invention is described above in connection with preferred or illustrative embodiments, these embodiments are not intended to be exhaustive or limiting of the invention. Rather, the invention is intended to cover any alternatives, modifications, or equivalents, which may be included within its spirit and scope, as defined by the appended claims. | An action toy system including a capsule for containing water having an orifice and a plunger and a spring loaded mechanism for driving the water from the orifice. The action toy may be configured as a shotgun accepting a plurality of prefilled shell capsules into its breechblock for firing through its barrel. It may also be configured as a missile launcher in which the capsules are mounted to the front of the launcher and the water is ejected directly from the capsule against the target. In yet another embodiment, the invention is configured as a crossbow with the bow loading the spring-loaded mechanism and a water stream obtained on release of the bow. In a still further embodiment, the action toy is fitted with a double feature nozzle for either producing a stream of water or propelling an object. | 5 |
The present application is a continuation of U.S. Ser. No. 11/049,619, filed Feb. 2, 2005 now U.S. Pat. No. 7,700,839 which claims the benefit pursuant to 35 U.S.C. §119 (a)-(d) of Australian Application No. 2004900498, filed Feb. 4, 2004, the disclosures of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
The present invention relates to improved cultivars of annual pasture and forage legumes of the Medicago genus (annual medics).
The present inventors have had extensive experience and success in the breeding and development of cultivars of pasture legume, in particular cultivars of annuals of the Medicago genus. Some years ago, they recognised that a major impediment to adoption and use of Medicago cultivars was seed cost, and that a major component of that seed cost related to the difficulty of harvesting and cleaning the seed. This is because, at maturity, the seed pods are dropped from the plant, and harvesting of seed entails vacuum harvesting the pods off the ground. The harvesting process is therefore slow, and requires specialised and powerful equipment, with large fuel inputs.
Accordingly, the present inventors sought to develop a medic that does not drop its seed pods and therefore can be harvested cheaply and efficiently with conventional harvesting equipment. This pod holding characteristic has never been recorded in naturally occurring annual medics.
Pod shedding is a result of growth of a layer of cells across the pedicel (pod stalk) at the base of the pod, which cuts off nutrient flows into the maturing pod and leads to effective separation of the pod from the pedicel. At the slightest disturbance, the pod then drops to the ground under its own weight and, by the time the plant has itself matured, the pod has been shed. Research has indicated that control of development of this abscission layer of cells is genetically controlled.
SUMMARY OF THE INVENTION
The present invention relates to improved cultivars, varieties, lines or plants of annual medics ( Medicago genus) wherein the majority of seed pods, upon reaching maturity, remain attached to their respective pedicels (this being referred to as the “pod holding” trait). In particular, the present invention relates to improved cultivars, varieties, lines or plants of annual medics ( Medicago genus), having a mutant form of the gene for pod shedding (ie for formation of an abscission layer between maturing seed pods and their respective pedicels), thereby resulting in the aforementioned “pod holding” trait.
In a further aspect of the invention, seed from known cultivars or wild-type varieties of annual medics ( Medicago genus) are subjected to treatment with a mutagenic agent, and improved cultivars, varieties, lines or plants having the aforementioned “pod holding” trait are isolated, eg by a selective breeding program. In particular, the mutated seeds are selected for the aforesaid “pod holding” trait (eg by growing the treated seeds, or descendants thereof, to maturity, assessing whether this trait is present, and selecting plants displaying this trait), and plants of the next generation are in turn grown from seeds of those selected plants, and then assessed. This process is repeated to isolate cultivars, varieties, lines or plants wherein the “pod holding” trait is stable and heritable. The mutagenic agent is, in particular, gamma radiation.
In the embodiment described below, selective breeding commenced with the M2 generation. The M2 seed was grown to maturity, and assessed for the “pod holding” trait. Plants of the M3 generation were in turn grown from seeds of selected plants of the M2 generation, and then assessed. This selective breeding process was repeated until the “pod holding” mutation was shown to be stable and heritable.
A yet further aspect of the invention relates to a method of transferring the “pod holding” trait from a cultivar, variety, line or plant having this trait to another annual medic of the genus Medicago by a process of controlled cross-breeding of said cultivar, variety, line or plant with said other annual medic and selection of progeny or descendants having the “pod holding” trait. In particular, the method can include the following steps:
(i) cross-breeding said cultivar, variety, line or plant with said other annual medic, and collecting hybrid seed resulting from this cross-breeding; (ii) planting said hybrid seed and producing F1 hybrid (first generation) plants therefrom; (iii) allowing the F1 plants to self-pollinate and set seed; (iv) planting the seed from the F1 plants and producing F2 (second generation) plants therefrom; (v) assessing the F2 or any later generation of plants for said “pod holding” trait and selecting said F2 or later generation plants having this trait.
A still further aspect of the invention relates to a method of obtaining plants having the “pod holding” trait from a population of annual medics of the genus Medicago . That population is derived by controlled or natural cross-breeding of annual medics, where one or more of the population parents carries one or more copies of the gene conferring the “pod holding” trait, and individual plants, progeny or descendants of the said population having the “pod holding” trait are selected. In particular, the method can include the following steps:
(i) obtaining a population derived from controlled or natural cross-breeding of an annual medic where one or more parents of said population have the “pod holding” trait or are progeny or descendants of controlled or natural cross-breeding involving one or more parents having the “pod holding” trait; (ii) growing plants of the population; (iii) assessing plants of the population or plants grown from seed harvested from any descendant generation of the population for said “pod holding” trait and selecting plants having this trait.
The progeny or descendants created by either of the aforesaid methods may also be selected for improved mature leaf retention, this being a trait directly associated with the “pod holding” trait.
DETAILED DESCRIPTION OF THE INVENTION
As a base cultivar for mutation treatment, Herald ( M. littoralis ) was used. A description of this base cultivar can be found in Plant Varieties Journal, 1996, Volume 9, Issue 2, page 49.
Chemical mutagenesis, using various doses of sodium azide (as suggested in the scientific literature), was initially trialled. However, after about a year, it was concluded that this treatment was insufficiently effective, as it resulted in high mortality rates, but low rates of mutation, at effective dosages. It was then decided to try irradiation.
Preliminary tests, carried out under the direction of the inventors by the International Atomic Energy Agency Plant Breeding Laboratories, Siebersdorf, Austria, showed that treatment of desiccated seed with between 200 and 300 Gy of gamma radiation (source: Cobalt 60) gave acceptably high levels of mutation, associated with low mortality. The gamma irradiated seed therefore showed higher treatment effects with respect to mutation, at lower rates of mortality, than was the case with chemical mutagenesis; this was confirmed in field trials (as described below).
Accordingly, seed was sent to the aforesaid Laboratories for treatment, and then returned to Australia, where greenhouse testing confirmed levels of treatment-induced mortality, and related growth retardant effects, on surviving M1 (first generation grown after the mutation treatment) plants. These M1 plants numbered about 700 and were derived from about 10 gm of treated seed.
The surviving M1 plants were grown and multiplied to produce about 500 gm of M2 seed. As expected, fertility rates were also significantly reduced as a result of the radiation treatment. Seed harvested from the M1 plants was then sown into the field, to produce 40 to 50,000 plants of generation M2. These were monitored for mutation effects and, in particular, for plants that held onto their pods at maturity.
This resulted in the isolation of approximately 40 plants with various degrees of pod holding. Nearly all (bar three) of these 40 plants exhibited relatively poor pod holding capabilities, but all were progeny tested to test the genetic nature and heritability of the observed pod holding.
All three of the good pod holding M2 plants showed very high heritability of the trait in the M3 and subsequent generations, with clear differences in this trait from all other medic plants, including other selected M2 progenies. There were also lesser differences observed in the strength of pod holding among the three good pod holders and their respective (cross-bred and self-pollinated) progenies. One plant and its self-pollinated progeny consistently showed stronger pod holding compared to the other two, and this plant also yielded higher strength pod holders from its cross-bred progeny.
Further testing showed that this pod holding characteristic is recessive and almost certainly due to mutation of a single gene, with the variation in the strength of characteristic expression which was observed in different plants and progenies indicating different mutations of the same gene in the original selections.
Seeds from a cultivar of Medicago littoralis having the “pod holding” trait have been deposited on May 26, 2009 with the National Collections of Industrial, Food and Marine Bacteria (NCIMB), having an address at Ferguson Building, Craibstone Estate, Bucksburn, Aberdeen AB21 9 YA Scotland, and are accessible under Deposit No 41621.
The pod holding mutation was found to significantly retard pod shedding in medics, with most pods being held on the vine long after the plant is mature and dried off. Because of the fragile nature of the pedicel and the weight of the pod, some pod shedding can be induced by mechanical disturbance, which is in itself an aid to harvesting, as the pod needs to be separated from the vine.
This trait forms a clear contrast with all other annual medics, where pods are shed even while the plants (and even the pods themselves) are still green, and hence the trait is clearly and easily observed in the field.
As a further and beneficial effect of the mutated gene [hereinafter referred to as the “ph” (for “pod holding”) gene], older leaves are also retained on the vine. This is because leaf shedding occurs by the same mechanism, with formation of an abscission layer at the base of each leaflet of the medic trifoliate, leading to leaf drop once the trifoliate is mature. Again, this leaf drop is very pronounced in the normal type of annual medic, with even old or slightly diseased leaves on relatively immature plants being frequently shed. As with pods, leaf drop on mature medics is virtually total once the plant is mature and dried off.
As with pod retention, mature leaf retention on plants with the ph trait is easily seen in the field, and is in marked contrast to leaf shed without the ph trait. The ph trait is readily seen in ph plants, not only in the retention of dead leaves on green plants, but also in their retention on the mature and dried off vine. By way of contrast, plants without the ph trait are left as leafless and pod-less stalks in the dried off state.
The pod holding and leaf holding traits are illustrated in the accompanying photographs ( FIGS. 1 to 4 ), which compare plants which are nearly isogenic (ie nearly genetically identical), except for the mutant ph gene. The photographs were all taken on the same date on plants with identical treatment.
FIG. 1 shows the normal type of annual medic, with no mature pods or leaves left on the plant.
FIG. 2 shows the mutant (ph gene) type, with mature, semi-mature and green pods and leaves still on the plant.
FIG. 3 shows the normal type of annual medic. The ground underneath the plant has both leaves and pods shed from the plant.
FIG. 4 shows the mutant (ph gene) type. The ground underneath the plant has very little pod or leaf material.
Our field trials have indicated that any substantial mutation of the naturally occurring form of the ph gene, being sufficient to disrupt production of the expression product of that gene, results in at least some degree of the pod holding trait. Cultivars with a sufficient degree of the pod holding trait, and with sufficient heritability of the characteristic, can then be selected, eg by a selective breeding program.
Further, testing has shown that the pod holding trait can be transferred between different annual medics through hybridisation and selection, and that the mutant gene behaves similarly to other nuclear genes within the plant. This enables new pod holding cultivars to be developed through cross breeding and selection.
Hand crosses between normal pod shedding plants and pod holding selections containing the mutant ph gene were made. Hybrid seed was planted and the F1 hybrid (first generation) plants which were produced all shed both mature pod and leaf in the same way as the normal pod shedding plants.
These F1 plants were then allowed to naturally self-pollinate and set seed. This seed was sown to produce an F2 generation. Individual plants were then assessed for pod and leaf holding. Plants with levels of mature pod and leaf holding that were similar to the pod holding parent, and in strong contrast to the pod and leaf shedding parent, all the F1 plants, and their sibling but non-pod holding F2 plants, were readily identifiable in this F2 generation. Approximately one quarter of individuals of the F2 population had this pod holding characteristic. In addition, all individual plants that exhibited either the mature pod holding or the mature leaf holding trait exhibited both traits together in the same plant.
Progeny derived from natural self-pollination of these selected pod and leaf holding plants were pure breeding for that characteristic; ie 100% of plants from subsequent (naturally self-pollinated) generations of the pod and leaf holding selections exhibited the pod and leaf holding trait.
These observations are all consistent with the genetic segregation expected from a cross between two parents that are genetically homozygous and pure breeding for the pod (and leaf) shedding, and the mutant pod (and leaf) holding, characteristics respectively, where the mutant pod (and leaf) holding characteristic is determined by a single recessive gene.
This has been further confirmed by selection within populations created by cross-breeding plants that do not themselves exhibit the “pod holding” trait, but are derived from hybrids or descendants thereof wherein at least one parent of the hybrid exhibits the “pod holding” trait. When these populations are allowed to self-pollinate and the seed is harvested and re-sown, individual progeny plants with the “pod holding” trait are found in subsequent generations. The frequency of occurrence of plants with the “pod holding” trait within these subsequent generations is again consistent with the genetic segregation expected if one of the original parents of the population carried the trait in the heterozygous state as a single recessive (ie unexpressed) gene. Expression of the “pod holding” characteristic in descendant generations of this population arises in those individuals where the recessive gene conferring the “pod holding” trait occurs in the homozygous condition, such occurrence arising through natural genetic segregation within the population.
As the mutant gene will therefore occur more or less randomly within hybrid populations that have at least one parent carrying the mutant ph gene in either the heterozygous or the homozygous state, new pod holding cultivars are developed by selection of different plants with the pod and leaf holding phenotype from within these populations. Plants exhibiting this trait are homozygous for the mutant gene and, being naturally self-pollinating, are thus pure breeding for the pod and leaf holding characteristic.
Using these methods of cross-breeding and selection, we have succeeded in transferring the “pod holding” trait of the present invention from the Medicago littoralis cultivar, into which the trait was first introduced, into plants of the species M. truncatula and M. tornata.
It should be noted that, while the present invention has been exemplified in terms of particular species of annual medic, the methods should be applicable to any annual medic of the genus Medicago. | The present invention relates to improved cultivars, varieties, lines or plants of annual medics ( Medicago genus) wherein the majority of seed pods, upon reaching maturity, remain attached to their respective pedicels. In particular, the present invention relates to improved cultivars, varieties, lines or plants of annual medics ( Medicago genus), having a mutant form of the gene for pod shedding, thereby resulting in a “pod holding” trait. The invention also extends to methods for isolating such plants. A yet further aspect of the invention relates to a method of transferring the “pod holding” trait from an annual medic having this trait to another annual medic of the genus Medicago by a process of controlled cross-breeding. A still further aspect of the invention relates to a method of obtaining plants having the “pod holding” trait from a population of annual medics of the genus Medicago. | 0 |
[0001] This application is a continuation of U.S. application Ser. No. 10/328,927, filed on Dec. 24, 2002, now U.S. Pat. No. 7,008,922; which is a continuation of U.S. application Ser. No. 09/000,217, filed on Jun. 26, 1998, now U.S. Pat. No. 6,521,598; which was a national stage application under 35 U.S.C. §371 of PCT/NL96/00307. The entire disclosures of the aforementioned patents are incorporated herein by reference.
[0002] The invention relates to the field of immunology, in particular to the field of cellular immunology.
[0003] It is also concerned with the area of organ transplantation, grafting of tissues or cells, especially bone marrow and possible immunological reactions caused by transplantation and/or grafting and bloodtransfusion.
[0004] Since the invention concerns a sex-related proteinaceous material, encoded in nature by a sex-related gene, the invention also relates to the areas of sex linked congenital aberrations, of embryonic selection techniques, in vitro fertilization techniques, vaccination and in ovo vaccination.
[0005] Bone marrow transplantation (BMT), one of the areas the invention is concerned with and the area from which the present invention originates, finds its application in the treatment of for instance severe aplastic anaemia, leukaemia and immune deficiency diseases.
[0006] In the early days of this technique many transplants failed through rejection of the graft by the host. Transplants that did succeed, however often led to an immune response by lymphocytes present in the graft against various tissues of the host (Graft versus Host Disease (GvHD)). It is now known that the GvHD response is mainly due to the presence of major H antigens which present a transplantation barrier. Therefor it is now routine practice to graft only HLA-matched materials (either from siblings or unrelated individuals) resulting in a much improved rate of success in bone marrow transplantation. However, despite this improvement, as well as improvements in pretransplantation chemotherapy or radiotherapy and the availability of potent immunosuppressive drugs, about 20-70% of the treated patients still suffer from GvHD (the percentage is age and bone marrow donor dependent). To avoid GvHD it has been suggested to remove the cells (mature T cells) causing said reaction from the graft. This however often leads to graft failure or to recurrence of the original disease. The cells responsible for GvHD are also the cells which often react against the original aberrant cells in for instance leukaemia (Graft versus Leukaemia response).
[0007] Since BMT is nowadays only carried out with HLA matched grafts, the GvHD which still occurs must be caused by another group of antigens. It is very likely that the group of so called minor H antigens (mHag), which are non-MHC encoded histocompatibility antigens (unlike the major H antigens) are at least partially responsible for the remaining incidence of GvHD.
[0008] mHag's have originally been discovered in congeneic strains of mice in tumor rejection and skin rejection studies. In mice, the use of inbred strains has shown that mHag are encoded by almost 50 different allelically polymorphic loci scattered throughout the genome (24). In humans, mHag have been shown to exist, although their overall number and complexity remains uncertain. One of the better known, though unidentified, minor histocompatibility antigens is the H-Y antigen. In the first report of H-Y as a transplantation antigen Eichwald and Silmser observed that within two inbred strains of mice, most of the male-to female skin grafts were rejected, whereas transplants made in other sex combinations nearly always succeeded (1). The term H-Y antigen was introduced by Billingham and Silvers (2) because the male specific antigen can function as a classical transplantation antigen responsible for homograft rejection.
[0009] Alloimmunity to human H-Y was first demonstrated in a female patient with aplastic anaemia who was given bone marrow from her HLA-identical brother. After a period of transient chimaerism the graft was rejected. At this time after grafting her lymphocytes showed unambiguously strong MHC restricted cytotoxic T cell (CTL) responses specific for male HLA-A2 positive target cells (3,4). The clinical case not only evidenced that H-Y can function as a transplantation barrier in man as well, but also that the recognition of the human male specific minor Histocompatibility antigen (mHag) was MHC restricted (4). The clinical relevance of H-Y as alloantigen is demonstrated especially in bone marrow transplantation (BMT) where sex-mismatch is one of the risk factors associated with rejection (3, 4, 5) or Graft-versus-Host-Disease (6, 7). Sensitization to the H-Y antigen extends to organ transplantation (8-11), bloodtransfusion (12) and pregnancy (13), wherein MHC restricted T cell responses to the mHag H-Y in association with different MHC molecules are observed. To understand the impact of mHag H-Y on the outcome of organ- and bone marrow grafting we earlier studied its tissue distribution. CTL mediated lysis of tissue-derived cell and cultured cell lines of several human tissues demonstrated an ubiquitous expression (11, 14, 16).
[0010] In search for the biological function of the gene encoding the mHag H-Y, our earlier studies analyzing lymphocytes from sex chromosomal abnormalities with our HLA restricted H-Y specific CTL clones revealed that absence of the mHag H-Y correlated with the XO and XX karyotype (17). Subsequent studies combining DNA, and functional expression with our CTL clones analyzing lymphocytes from individuals with Y chromosomal deletions, assigned the H-Y gene encoding the mHag H-Y to a portion of interval 6 (18), to a region covering the proximal segment of the Yq euchromatin, on the long arm of the Y chromosome (19).
[0011] Besides the role of H-Y as transplantation antigen, the human Y gene controlling the expression of the mHag H-Y is possibly also functioning as a gene controlling spermatogenesis. Agulnik et al. (20) recently identified a new murine Y chromosome gene, designated Smcy, controlling spermatogenesis as well the expression of the murine male specific mHag H-Y. The Smyc gene appears to be conserved on the Y chromosome in mouse, man and even in marsupials (20). It is notable that recent studies from our laboratories show recognition of the human HA-2 and H-Y peptides on non human primates cells, transfected with human class I genes, by our human HA-2 and H-Y specific class I restricted CTL clones (21).
[0012] Until recently, little was known about the molecular nature of the mHag gene products. Recent evidence was obtained revealing that the non-sexlinked human mHag HA-2 represents a short peptide originating from a member of the non-filament-forming class I myosin family (22). However, no information exists on the amino-acid sequence nor on the protein of the male specific mHag H-Y.
[0013] Aiming at the identification of the human H-Y peptide, we used the HLA-B7 restricted CTL clone “5W4” (12). Clone 5W4 originates from a female aplastic anemia patient who had received mutiple transfusions (12, 23).
[0014] Besides the HLA-B7H-Y specific CTL clone, we earlier characterized HLA-A2 as well as HLA-A1H-Y specific CTL clones (23).
[0015] We used a CD8 positive HLA-A2.1 restricted H-Y specific CTL clone, designated “1R35” (23). Besides, we also previously characterized a CD4 positive HLA-A2.1 restricted H-Y specific cytotoxic as well as proliferative T cell clone, designated as “R416” (41).
[0016] We aimed at identification of the human H-Y peptide recognized by the HLA-A2.1 restricted H-Y specific T cell clones IR35 and R416. The same methodology as applied for the identification of the HLA-B7 restricted H-Y peptide was used.
[0017] The invention thus provides a (poly)peptide comprising a T-cell epitope obtainable from the minor Histocompatibility antigen H-Y comprising the sequence SPSVDKARAEL (SEQ ID NO:1) or FIDSYICQV (SEQ ID NO:2) or a derivative of either of these having similar immunological properties.
[0018] The two sequences specified are encoded by the SMCY gene. The first sequence is the one found using the HLA-B7 restricted H-Y specific T-cell clone. The second is the one found using the HLA-A2.1 restricted clones.
[0019] The way these sequences are obtained is described herein. An important part of this novel method of arriving at said sequences is the purification and the choice of the starting material. Said novel method is therefor also part of the scope of this invention. However, now that the sequence is known, it is of course no longer necessary to follow that method, because the peptides can easily be made synthetically, as is well known in the art. Since routine techniques are available for producing synthetic peptides, it is also within the skill of the art to arrive at analogs or derivatives of the explicitly described peptides, which analogs and/or derivatives may have the same or at least similar properties and or activity. On the other hand analogs which counteract the activity of the explicitly described peptides are also within the skill of the art, given the teaching of the present invention. Therefor derivatives and/or analogs, be it of the same or different length, be it agonist or antagonist, be it peptide-like or peptidomirnetic, are part of the scope of this invention.
[0020] A preferred embodiment of the present invention are the peptides with the sequences SPSVDKARAEL (SEQ ID NO:1) and/or FIDSYICQV (SEQ ID NO:2). This does not imply that other peptides are not suitable. This will for a large part depend on the application and on other properties of the peptides, which were not all testable within the scope of the present invention.
[0021] The peptides and other molecules according to the invention find their utility in that they may be used to induce tolerance of the donor immune system in H-Y negative donors, so that residual peripheral blood lymphocytes in the eventually transplanted organ or the bone marrow, as it may be, do not respond to host H-Y material in an H-Y positive recipient. In this way GvHD may be prevented. On the other hand tolerance may be induced in H-Y negative recipients in basically the same way, so that upon receipt of an organ or bone marrow from an H-Y positive donor no rejection on the basis of the H-Y material occurs.
[0022] For tolerance induction very small doses can be given repeatedly, for instance intravenously, but other routes of administration may very well be suitable too. Another possibility is the repeated oral administration of high doses of the peptides. The peptides may be given alone, or in combination with other peptides, or as part of larger molecules, or coupled to carrier materials in any suitable excipients.
[0023] Further applications of the peptide or derivatives thereof lie in the prophylactic administration of such to transplanted individuals to prevent GvHD. This can be done with either agonists, possibly in combination with an adjuvant, or with antagonists which may block the responsible cells. This can be done with or without the concomitant administration of cytokines.
[0024] Furthermore the peptides or antibodies thereto can be used in so called “magic bullet” applications, whereby the peptide or the antibody is coupled to a toxic substance to eliminate certain subsets of cells.
[0025] Diagnostic applications are clearly within the skill of the art. They include, but are not limited to, H-Y typing, detection of genetic aberrancies and the like.
[0026] Other therapeutical applications of the peptide include the induction of tolerance to H-Y proteins in H-Y related (auto)immune diseases, such as possibly in Rheumatoid arthritis. On the other hand they may be used in vaccines in H-Y related (auto)immune diseases.
[0027] For the sake of illustration a number of applications is cited below.
[0028] The H-Y peptide or its derivatives can be used to prevent harmful reaction of the recipient towards the donor or vice versa; in all forms of transplantation i.e. organs, tissues and bone marrow. Assuming that residual donor peripheral blood lymphocytes (PBL)'s in the transplanted organ could react with and/or against host PBL's and even could cause GvHD, the H-Y peptide could be used to induce tolerance in living organ (kidney, liver, gut, skin) of H-Y negative donors for H-Y positive patients. In bone marrow transplantation, the H-Y peptide (given alone or in combination with other peptides) can be used to induce tolerance in the living bone marrow donor. The peptide(s) can be given orally, intravenous or otherwise.
[0029] In all forms of organ (including cornea), tissue (including heartvalves and skin) and bone marrow transplantation with living or cadaveric donors, the H-Y peptide could be used to induce tolerance in H-Y negative recipients of organ and tissue transplants from H-Y positive donors. In case of bone marrow transplantation, tolerance must be induced in female donors for male recipients. The tolerance induction can be achieved by clinical application of the H-Y peptide systematically, i.v., locally, orally, as eye-drops.
[0030] The H-Y peptides could act in a non-allelic restricted manner (thus promiscuous) implicating that its applicability to inducing tolerance is not restricted to the HLA type of the female donors and female recipients and donors.
[0031] The H-Y peptides or their derivatives can be applied to generate reagents and/or medicine. They can be used as Graft-versus-Host disease and rejection prophylaxis administration to the transplanted individual either with or without adjuvant of
[0032] a) a H-Y peptide
[0033] b) H-Y peptide analogues, including left or right turning peptides
[0034] c) H-Y peptide antagonists
[0035] Usage of the H-Y sequence information to generate, for immunomodulatory purposes:
[0036] a) anti-idiotypic T cells
[0037] b) anti-idiotypic B cells
[0038] c) human monoclonal antibodies
[0039] The H-Y peptides or their derivatives can be used as a marker for sex linked congenital or other diseases.
[0040] They can be used for the generation of a genetic probe enabling screening for the congenital sex-linked disorders.
[0041] The genetic probe can be used for genetic counseling, population genetics and pre-natal diagnostic.
[0042] The defect can be repaired by genetic engineering.
[0043] The peptides and other molecules according to the invention can also be used for the production of anti-conceptive drugs.
[0044] Furthermore the peptides and other molecules according to the invention can be used for the production of cytotoxic T lymphocytes (CTL) with specificity for the H-Y sequence.
[0045] The H-Y specific CTL can be used for selection of male embryos in X linked recessive disorders.
[0046] The invented molecules can be applied to generate reagents and/or medicine for
[0047] a) determination of foetal erythrocytes in maternal circulation.
[0048] b) intra uterine diagnostics
[0049] c) use prior to implantation for in vitro fertilization.
[0050] d) determination of chimerism.
[0051] Veterinary applications include:
[0052] a) embryonic selection.
[0053] b) in vitro fertilization.
[0054] c) vaccination and in ovo vaccination
[0055] d) anti-conception.
[0056] On the basis of the peptides described herein, genetic probes can be produced which can be used to screen for the gene encoding the protein. On the other hand such probes may be useful in detection kits as well. On the basis of the peptides described herein anti-idiotypic B cells and/or T cells and antibodies can be produced. All these embodiments have been made possible by the present disclosure and therefor are part of the present invention.
[0057] The techniques to produce these embodiments are all within the skill of the art.
[0058] Dose ranges of peptides and antibodies and/or other molecules according to the invention to be used in the therapeutical applications as described herein before are usually designed on the basis of rising dose studies in the clinic. The doses for peptides may lie between about 0.1 and 1000 μg per kg bodyweight, preferably between 1 and 10 μg per kg bodyweight.
BRIEF DESCRIPTION OF THE DRAWINGS
[0059] FIG. 1 . Reconstitution of the H-Y epitope with HPLC fractionated peptides extracted from HLA-B7 molecules. (A) HLA-B7 molecules were immunoaffinity purified from 2×1010H-Y positive JY cells. Peptides were eluted from B7 molecules with 10% acetic acid, pH 2.2, filtered through a 10 kD cut-off filter and fractionated on a C18 reverse phase column. Buffer A was 0.1% heptafluorobutyric acid (HFBA); buffer B was 0.1% HFBA in acetonitrile. The gradient consisted of 100% buffer A (0-20 min), 0 to 12% buffer B (20 to 25 min), and 12 to 50% buffer B (25 to 80 min) at a flow rate of 200 μl/min. 60 fractions of 200 μl each were collected from 20 to 80 min. (B) Fractions 28 and 29 from the separation shown in (A) were rechromatographed with the same acetonitrile gradient, but using trifluoroacetic acid (TFA) instead of HFBA as the organic modifier. For both panels, 3% of each peptide fractions were preincubated with 1,000 51 Cr-labeled T2-B7 cells at room temperature for 2 hours. CTLS were then added at an effector to target ratio of 10 to 1, and further incubated at 37° C. for 4 hours. Background lysis of T2-B7 by the CTL in the absence of any peptides was −3% in (A) and −4% in (B); positive control lysis of JY was 75% in (A) and 74% in (B).
[0060] FIG. 2 . Determination of candidate H-Y peptide by mass spectrometry combined with 51 Cr release assay. HPLC fraction 14 from the separation shown in FIG. 1B was chromatographed with an on-line microcapillary column effluent splitter as previously described (11, 13). One-fifth of the effluent was deposited into μl of culture media in microtiter plate wells for analysis with CTLs as in FIG. 1 . The remaining four-fifths of the material were directed into the electrospray ionization source, and mass spectra of the peptides deposited in each well were recorded on a triple-quadruple mass spectrometer (Finnigan-MAT, San Jose, Calif.).
[0000] (♦), H-Y epitope reconstitution activity measured as percent specific lysis; (▪), abundance of peptide 1171 measured as ion current at m/z 391.
[0061] FIG. 3 . CAD mass spectrum of peptide 1171 after conversion the R residue to ornithine. material from second dimension HPLC fraction 14 shown in FIG. 1B was treated with 70% hydrazine hydrate for 1 hour. The CAD mass spectrum was recorded on the (M+2H)+2 ion at m/z 566.
[0062] FIG. 4 . H-Y epitope reconstitution with synthetic peptides. Synthetic peptides were purified to homogeneity by reverse phase-HPLC on a Vydac C4 column. Purity was established on an analytical RP column and the quantity of each peptide was confirmed by comparing the area of the peak with that of a standard peptide. The identity of the peptides was confirmed by mass spectrometry. 51 Cr release was assayed at an effector to target ratio of 10 to 1 on T2-B7 cells that had been incubated with the indicated concentration of SMCY peptide SPSVDKARAEL (SEQ ID NO:1) (♦), or SMCX peptide SPAVDKAQAEL (SEQ ID NO:3) (▪).
[0063] FIG. 5 . Binding of synthetic peptides to purified HLA-B7. HPLC-purified test peptides were assayed for the ability to inhibit the binding of the iodinated endogenous B7 peptide APRTYVLLL (SEQ ID NO:4) to purified HLA-B7 as previously described (40). (♦), SMCY peptide SPSVDKARAEL (SEQ ID NO:1); (▪) SMCX peptide SPAVDKAQAEL (SEQ ID NO:3); (Δ), APRTLVLLL (SEQ ID NO:5), an endogenous peptide bound to HLA-B7; (x) LLDVPTAAV (SEQ ID NO. 6), an endogenous peptide bound to HLA-A2.1 as the negative control.
[0064] FIG. 6 . HLA-A2 molecules were immunoaffinity purified from 1010 DM cells. Peptides were eluted according to the methodology as described in legend to FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0065] As with other mHag, the recognition of H-Y by T lymphocytes is MHC-restricted (3, 24, 25), and it has been shown that some H-Y antigens are peptides derived from cellular proteins that are presented on the cell surface in association with MHC class I molecules (26). We have developed a technique for the identification of individual peptides that are bound to MHC molecules and recognized as antigens by T cells. By combining microcapillary liquid chromatography/electrospray ionization mass spectrometry with T cell epitope reconstitution assays, we previously identified peptide antigens recognized by T cells specific for human melanoma (27), human xenografts (28), and a non-sex-linked human mHag (22). We now report the identification of a peptide antigen recognized by a human cytotoxic T lymphocyte (CTL) clone that is H-Y specific and restricted by the class I MHC molecule HLA-B7, as well as a peptide antigen that is recognized by two HLA-A2.1 restricted CTL clones.
[0066] To isolate endogenously processed H-Y peptides, HLA-B7 molecules were purified by affinity chromatography from the H-Y positive, B lymphoblastoid cell line, JY (29). The associated peptides were extracted in acid and separated from high molecular weight material by ultrafiltration as previously described (31), and subsequently fractionated by reverse-phase high-performance liquid chromatography (HPLC) (27). Aliquots of each fraction were incubated with HLA-B7 positive, H-Y negative T2-B7 target cells in order to assay for the ability to reconstitute the epitope recognized by an HLA-B7-restricted, H-Y specific CTL clone, 5W4 (ref. 12). A single peak of reconstituting activity was observed ( FIG. 1A , fraction 28 and 29), which was rechromatographed using a different organic modifier. Although a single active peak of reconstituting activity was also observed from this separation ( FIG. 1B , fraction 14, 15 and 16), it still contained more than 100 distinct peptide species, as assessed by electrospray ionization tandem mass spectrometry.
[0067] To identify active H-Y peptides in this mixture, we applied each active fraction separately to a microcapillary HPLC column and split the effluent following the separation (11): Four-fifths of the effluent was directed into the mass spectrometer for analysis, while one-fifth was simultaneously directed into a 96-well microtiter plate for a subsequent epitope reconstitution assay. The amount of the H-Y sensitizing activity in each well was correlated to signals observed in the mass spectrum, and therefore to the abundance of different peptide species. By comparing the profile of H-Y activity and the ion abundance data ( FIG. 2 ), we were able to identify an (M+3H)+3 ion at a mass-to-charge ratio (m/z) of 391 (neutral molecular mass=1171), whose abundance correlated with the amount of H-Y epitope reconstituting activity. Further confirmation of the importance of peptide 1171 was provided by the demonstration that a peptide with an identical mass and collision-activated dissociation (CAD) spectrum was also present in HLA-B7 associated peptides extracted from a second H-Y positive B lymphoblastoid line, DM, but absent from a spontaneous H-Y antigen loss variant of this cell, DM (−)
[0068] (33).
[0069] Assignment of a complete amino acid sequence to the 1171 peptide from the CAD mass spectrum recorded at the 20 fmol level proved difficult due to the absence of high mass fragment ions containing the amine terminus (b-type ions). A series of single and/or doubly charged fragment ions containing the amine terminus (b-type ions). A series of single and/or doubly charged fragment ions containing the carboxyl terminus (y-type ions) identified the C-terminal residue as either L or I and the first six amino acids as SPSVDK (SEQ ID NO:7). The difference in molecular mass between this partial sequence and that of the full length peptide suggested the presence of four additional residues, for a total length of 11. Since the candidate peptide existed exclusively in the gas phase as an (M+3H)+3 ion, and underwent mass shifts of 42 and 84 Da on conversion to the corresponding methyl ester and acetylated derivative, respectively, two of the remaining residues were assigned as R and either D or E. Only two combinations of four residues (AREA (SEQ ID NO: 8) and GRDV (SEQ ID NO:9)) meet the above criteria and satisfy the missing mass of 427 Da. CAD spectra recorded on synthetic peptides suggested that R could not be located at either position 7 or 10. Data bases were searched for proteins containing peptides with these characteristics, and a sequence consistent at 9 out of 11 positions was found in residues 909-919 of the protein encoded by a gene called XE169 or SMCX (34), which is located on the X chromosome. A homolog of SMCX, called SMCY, is located on the Y chromosome (20). This protein (35) contains a sequence (residues 902-912) that is consistent at 11 out of 11 positions, and has the expected mass of 1171 Da. A CAD mass spectrum recorded on the naturally processed material after conversion of the R residue to ornithine confirmed that its sequence was identical to that found in SMCY protein ( FIG. 3 ).
[0070] In the same manner as described above for the HLA-B7 restricted T-cell clone, the peptide recognized by two HLA-A2.1 T-cell clones was identified. In short the HLA-A2.1 restricted H-Y specific T cell clone R416 recognizes HPLC fraction 34, the HLA-A2.1 restricted H-Y specific T clone 1R35 recognizes HPLC fractions 36 and 39 ( FIG. 6 ). The amino acid sequence analyses and H-Y reconstitution assays demonstrate that both HLA-A2.1 restricted H-Y specific T cell clones recognize peptide sequence FIDSYICQV (SEQ ID NO:2) with a m/z ratio of 544 or the cystinylated form of the same peptide with a m/z ratio of 604.
[0071] A synthetic peptide corresponding to the 11 residue SMCY sequence (SPSVDKARAEL (SEQ ID NO:1)) was found to sensitize T2-B7 cells for recognition by the H-Y specific CTL clone. Half-maximal lysis was achieved at a peptide concentration of 10 pM ( FIG. 4 ). The corresponding peptide derived from the sequence of the X chromosomal homolog, SMCX, has substitutions of A for S at position 3 and Q for R at position 8. Although this peptide also was able to sensitize T2-B7 cells for recognition, comparable levels of killing were only achieved by using a 10,000-fold higher peptide concentration. Binding studies showed that the concentration of the SMCY peptide that inhibited the binding of an iodinated standard peptide to purified HLA-B7 by 50% (IC50) was 34 nM, while the IC50 for the SMCX peptide was 140 nM ( FIG. 5 ). Thus, the significant difference in the ability of the SMCY and SMCX peptides to sensitize targets for T cell recognition is almost entirely due to the fine specificity of the T cell receptor, rather than to differences in MHC binding affinities. The SMCX peptide is also present in naturally processed peptide extracts of HLA-B7, although its abundance is only 25% of that of the SMCY peptide (33). Based on all of this information, it is concluded that the peptide epitopes representing the HLA-B7 restricted H-Y antigen is derived from the protein encoded by SMCY, which is also true for the HLA-A2.1 recognized peptide, also encoded by SMCY.
[0072] The location of the SMCY gene and the control of its expression fit well with those expected of the H-Y antigen based on previous work. Deletion mapping in humans has placed the HY locus to a portion of interval 6 on the long arm of the human Y chromosome (18), and SMCY maps to this same interval (20). H-Y antigens are expressed ubiquitously in different tissues (5, 15), and expression of SMCY has been detected in all male tissues tested (20). One interesting issue is whether the H-Y epitope peptides presented by other MHC molecules will also be derived from SMCY. SMCY and SMCX are 85% identical at the amino acid sequence level, and the SMCX gene is expressed ubiquitously from both the active and the inactive X chromosomes in both mice and human (34, 36). Therefore, self-tolerance to SMCX will limit the number of SMCY peptides that could give rise to H-Y epitopes in association with different MHC molecules. On the other hand, SMCY contains almost 1500 residues, and the over 200 amino acid sequence differences between it and SMCX are scattered relatively uniformly throughout its length. Thus, there is the potential to generate a large number of distinct SMCY-specific peptides as H-Y epitopes. It is still an open question whether the H-Y epitope peptides presented by other MHC molecules are also derived from SMCY. Genetic mapping of the mouse Y chromosome has suggested at least two and up to five distinct loci encoding H-Y antigens (37). Interestingly, a murine H-Y epitope restricted by H-2Kk has also been shown to be derived from the murine Smcy protein (38). The demonstration that two H-Y epitopes from either mouse or human are derived from the same protein makes SMCY the prime target in searching other H-Y epitopes.
[0073] The identification of the protein that gives rise to an H-Y antigen culminates 40 years of uncertainty regarding its origin. However, the function of SMCY, as well as the homologous SMCX, remains unclear. Both proteins share significant sequence homology to retinoblastoma binding protein 2, which has been suggested to be a transcription factor (39). Nonetheless, this and other H-Y specific peptides are candidates for immunomodulatory approaches in bone marrow transplantation. They may also form the basis for genetic probes to be used for prenatal diagnosis in sex-linked congenital abnormalities, as well as for investigating minimal residual disease and chimerism.
REFERENCES
[0000]
1. E. J. Eichwald, C. R. Silmser.: Transplant Bull; 148-149, 1955.
2. R. E. Billingham, W. K. Silvers: Studies on tolerance of the Y chromosome antigen in mice. J. Immunol. 85: 14-26, 1960.
3. E. Goulmy, A. Termijtelen, B. A. Bradley, J. J. van Rood. Alloimmunity to human H-Y. Lancet ii: 1206, 1976.
4. E. Goulmy, A. Termijtelen, B. A. Bradley, J. J. van Rood. Y-antigen killing by T cells of women is restricted by HLA. Nature 266: 544-545, 1977.
5. P. J. Voogt, W. E. Fibbe, W. A. F. Marijt, E. Goulmy, W. F. J. Veenhof, M. Hamilton, A. Brand, F. E. Zwaan, R. Willemze, J. J. van Rood, J. H. F. Falkenburg. Rejection of bone marrow graft by recipient derived cytotoxic T lymphocytes against minor histocompatibility antigens. Lancet 335: 131-134, 1990.
6. M. M. Bortin for the Advisory Committee of the international Bone Marrow Transplant Registry: Acute graft-versus-host disease following bone marrow transplantation in humans: prognostic factors. Transplant Proc 19: 2655-2657, 1987.
7. Report from the international Bone Marrow Transplant Registry: Bone Marrow Transplant 4: 221-228, 1989.
8. E. Goulmy, B. A. Bradley, Q. Lansbegen J. J. van Rood. The imporance of H-Y incompatibility in human organ transplantation. Transplantation 25: 315-319, 1979.
9. P. F. Pfeffer, E. Thorsby. HLA-restricted cytotoxicity against male specific (H-Y antigenafter acute rejection of an HLA identical sibling kidney. clonal distribution of the cytotoxic cells. Transplantation 33: 52-56, 1982.
10. Y. Beck, M. Sekimata, S. Nakayama et al. Expression of human minor Histocompatibility antigen on cultured kidney cells. Eur. J. Immunol. 23: 467-472, 1993.
11. E. Goulmy, J. Pool, E. van Lochem and H. Volker-Dieben. The role of human minor Histocompatibility antigens in graft failure: a mini-review. Eye 9: 180-184, 1995.
12. E. Goulmy, J. D. Hamilton and B. A. Bradley. Anti-self HLA may be clonally expressed. J. Exp. Med. 149: 545-550, 1979.
13. D. P. Singal, Y. J. Wadia, N. Naipaul. In vitro cell-mediated cytotoxicity to the male specific (H-Y) antigen in man. Human Immunol. 2: 45-53, 1981.
14. P. J. Voogt, E. Goulmy, W. E. Fibbe, W. F. J. Veenhof, A. Brand, J. H. F. Falkenburg. Minor histocompatibility antigen H-Y is expressed on human haematopoietic progenitor cells. J. Clin. Invest. 82: 906-912, 1988.
15. M. de Bueger, A. Bakker, J. J. van Rood, F. van der Woude and E. Goulmy. Tissue distribution of human minor histocompatibility antigens. Ubiquitous versus restricted tissue distribution indicates heterogeneity among human cytotoxic T lymphocyte-defined non-MHC antigens. J. of Immunol. 149, 5: 1788-1794, 1992.
16. D. van der Harst, E. Goulmy, J. H. F. Falkenburg, Y. M. C. Kooij-Winkelaar, S. A. P. van Luxemburg, H. M. Goselink and A. Brand. Recognition of minor Histocompatibility antigens on lymphocytic and myeloid leukemic cells by cytotoxic T-cell clones. Blood 83: 1060-1066, 1994.
17. E. Goulmy, A. van Leeuwen, E. Blokland, E. S. Sachs and J. P. M. Geraedts. The recognition of abnormal sex chromosome constitution by HLA-restricted anti-H-Y cytotoxic T cells and antibody. Immunogenetics 17: 523-531, 1983.
18. M. A. Cantrell, J. S. Kogan, E. Simpson, J. N. Bicknell, E. Goulmy, P. Chandler, R. A. Pagon, D. C. Walker, H. C. Thuline, J. M. Graham Jr., A. de La Chaeplle, D. C. Page and C. M. Disteche. Deletion mapping of H-Y antigen to the long arm of the human Y chromosome. Genomics 13: 1255-1260, 1992.
19. A. J. O'Reilly, N. A. Affara, E. Simpson, P. Chandler, E. Goulmy and M. A. Ferguson-Smith. A molecular deletion map of the Y chromosome long arm defining X and autosomal homologous regions and the localisation of the HYA locus to the proximal region of the Yq euchromatin. Human Mol. Gen. 1: 379-385, 1992.
20. A. Agulnik, M. J. Mitchell, J. L. Lerner, D. R. Woods and C. Bishop. A mouse Y chromosome gene encoded by a region essential for spermatogenesis and expression of male specific minor Histocompatibility antigens. Human Molecular Genetics 3: 873-878, 1994.
21. J. M. M. den Haan, J. Pool, N. Sherman, E. Blokland, R. Bontrop, V. H. Engelhard, D. F. Hunt and E. Goulmy. Minor Histocompatibility antigens are conserved between human and non-human primates. Manuscript submitted for publication.
22. J. M. M. den Haan, N. E. Sherman, E. Blokland, E. Huczko, F. Koning, J-W. Drijfhout, J. Skipper, J. Shabanowitz, D. F. Hunt, V. H. Engelhard, E. Goulmy. Identification of graft versus host disease-associated human minor Histocompatibility antigen. Science 268: 476-1480, 1995.
23. E. Goulmy. In: Transplantation Reviews vol. 2. {J. Morris and N. C. Tilney Eds. Saunders, Philadelphia, 1988: pp 29-53.
24. B. Loveland, E. Simpson, Immunol. Today 7, 223 (1986).
25. R. D. Gordon, E. Simpson, L. E. Samelson, J. Exp. Med. 142, 1108 (1975).
26. O. Rotzschke, K. Falk, H. J. Waliny, S. Faath, H. G. Rammensee, Science 249, 283 (1990).
27. A. L. Cox et al, Science 264, 716 (1994).
28. R. A. Henderson et al, Proc. Natl. Acad. Sci. USA 90, 10275 (1993).
29. M. J. Turner et al, J. Biol. Chem. 250, 4512 (1975);
30. P. Parham, B. N. Alpert, H. T. Orr, J. L. Strominger, J. Biol. Chem. 252, (1977).
31. D. F. Hunt et al, Science 255, 1261 (1992);
32. E. L. Huczko et al, J. Immunol. 151, 2572 (1993).
33. L. R. Meadows, W. Wang, N. E. Sherman, J. M. den Haan, unpublished results.
34. J. Wu et al, Human Molecular Genetics 3, 153 (1994);
35. A. I. Agulnik, C. E. Bishop, unpublished results.
36. J. Wu et al, Nature Genetics 7, 491 (1994).
37. T. R. King et al, Genomics 24, 159 (1994)
38. D. M. Scott et al, unpublished results.
39. A. R. Fattaey et al, Oncogene 8, 3149 (1993).
40. J. Ruppert et al, Cell 74, 929 (1993); Y. Chen et al, J. Immunol. 152, 2874 (1994); A. Sette et al, J. Immunol. 153, 5586 (1994).
41. M. de Bueger, A. Bakker, E. Goulmy, Existence of mature human CD4+ T cells with genuine class I restriction, Eur. J. Immunol. 1992, 22: 875-878. | The present invention relates to a peptide which is immunologically recognizable as a T cell epitope of the minor Histocompatibility antigen H-Y. The peptide comprises amino acid sequence SPSVDKARAEL (SEQ ID NO: 1) or FIDSYICQV (SEQ ID NO: 2). The peptide is obtainable from the minor Histocompatibility antigen H-Y. Providing a toxic moiety to the peptide eliminates T cells having specific binding affinity for the peptide. The peptide induces tolerance for transplantations when administered to H-Y-negative recipients. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
This is the 35 USC 371 national stage of International application PCT/NL97/00418 filed on Jul. 16, 1997, which designated the United States of America.
FIELD OF THE INVENTION
The invention relates to a new sulphur-reducing bacterium and to a process for removing sulphur compounds from water.
BACKGROUND OF THE INVENTION
The presence of sulphur compounds in water is usually an unacceptable factor. In the case of sulphate, sulphite and thiosulphate, the principal drawbacks are attack on the sewer, acidification, eutrophication, and silting. One type of effluent in which sulphur compounds, in particular sulphite, are a constituent which is difficult to remove is the wash water from flue gas treatment plants. The flue gases from power stations and waste incinerators cause extensive pollution of the environment due to the presence of acidifying sulphur dioxide (SO 2 ). Other types of effluents containing sulphur compounds are those originating from the printing industry, mining industry, and paper, rubber, leather and viscose industry.
The biological treatment of sulphate and sulphite and other sulphur compounds, including scrubbing liquids from flue gas desulphurisation plants, involves reduction in an anaerobic step to give sulphide, which in turn can be biologically oxidised to elementary sulphur. Such processes are known, for example from EP-A-451922, WO-A-92/17410 and WO-A-93/24416.
The advantage of such processes is that only small waste streams remain because the sulphur formed can be re-used. However, the disadvantage is that, especially when the effluent contains little organic matter, electron donors have to be added in order to provide sufficient reduction equivalents for the sulphate reducing bacteria (SRB). The most important electron donors are methanol, ethanol, glucose and other saccharides, organic acids, such as acetic, propionic, butyric and lactic acid, hydrogen and carbon monoxide. The use of these electron donors has the effect of substantially increasing the cost of this method for removal of sulphur from waste streams.
WO-A-92/17410 discloses that sulphur compounds, in particular SO 2 can be effectively removed from water by continuous or periodical use of a temperature above 45° C. during the anaerobic treatment, without large amounts of added electron donor being needed, because little or no methane is produced.
According to WO-A-93/24416, the consumption of electron donor can be reduced by selecting a minimum sulphate/sulphite concentration in the anaerobic reactor effluent and/or a minimum sulphide concentration in the reactor and/or by raising the salt concentration. Such measures are more favourable to the SRB than to the methanogenic bacteria, and therefore reduce the total demand for electron donors.
Although such measures have improved the utility of biological desulphur-isation processes, the performance is always limited by the properties of the micro-organisms used. The conventional SRB's used belong to the genera Desulfovibrio, Desulfotomaculum, Desulfomonas, Desulfobulbus, Desulfobacter, Desulfococcus, Desulfonema, Desulfosarcina, Desulfobacterium and Desulfuromonas.
SUMMARY OF THE INVENTION
A new microorganism has been found now which exhibits remarkable and useful properties in the biological reduction of sulphur compounds at high temperatures.
The new microorganism is a bacterium which was isolated from a burning coal heap in Sweden. It can produce high sulphide concentrations from higher oxidised sulphur species such as sulphate and sulphite. High sulphide concentrations, up to 2.5 g/l, can be tolerated by the bacterium without negative consequences for its vitality.
The strain as isolated is denoted as KT7 and consists of short rods, about 0.7-1 μm in diameter and 1-2 μm in length. They stain Gram positive. They are highly motile and several flagellae are visible with electron microscopy. The cells are covered by a protein surface layer. Subunits are regulary arranged with p2 or p4 symmetry.
The bacteria according to the invention fit in the group of the low-GC Gram-positives, and are related to the genus Desulfotomaculuni. They have the characteristics of strain KT7. Strain KT7 has been deposited at the DSMZ in Braunschweig, Germany, on Jun. 19th 1996 with accession number DSM 11017.
The strain K17 is capable of growing in various media. The data of growth on various electron donors and acceptors (concentration 0.1%) after incubation for 3 days are summarised in Table 1 below; the tests were performed under a 80% N 2 , 20% CO 2 atmosphere (2 bar), except for the test with molecular hydrogen which was performed under a 65% N 2 , 20% CO 2 and 15% H 2 atmosphere.
TABLE 1
e-acceptor
e-donor
sulphite
sulphate
nitrate
molecular hydrogen
+++
(+)
(+)
formate
++
(+)
n.d.
acetate
++
−
—
ethanol
+
(+)
—
lactate
+++
n.d.
(+)
isopropanol
+
n.d.
−
pyruvate
+++
n.d.
−
fumarate
(+)
n.d.
n.d.
citrate
−
n.d.
n.d.
D-glucose
(+)
n.d.
n.d.
yeast extract
(+)
n.d.
n.d.
Cell concentrations (cells/ml):
− = no growth
(+) = <10 7
n.d. = no data
+ = 1.10 7 to 3.10 7
++ = 3.10 7 to 6.10 7
+++ = >6.10 7
The bacteria according to the invention grow between 35 and 85° C., with considerable growth between 48 and 70° C. The temperature optimum is in the range 50-65° C. with a doubling time of 90 minutes. The pH range for growth is about 5 to 9, with an optimum at 6.5-7.5. The bacteria are active both as free cells and as aggregates.
Strain KT7 is strictly anaerobic. It tolerates up to 25% carbon monoxide in the gas phase. In full scale installations, it is expected that the bacteria can tolerate up to 50% carbon monoxide.
The bacterium according to the invention can be used in various anaerobic processes, especially where sulphate and other sulphur species are reduced to sulphide.
Thus, the invention relates to any process for the biological removal of sulphur compounds from an aqueous solution of dispersion wherein the bacterium as described above is used. The bacterium can be used alone, but also in combination with other, conventional sulphur-reducing microorganisms. An important advantage of the bacterium of the invention is that it can produce high levels of sulphide, about twice as much as conventional sulphur-reducing bacteria, and thus makes the sulphur-reducing process more efficient (higher capacity and/or smaller equipment and/or shorter residence times).
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 depict suitable installations for carrying out the invention.
DETAILED DESCRIPTION OF THE INVENTION
A particular embodiment of the process according to the invention is the use in flue gas desulphurisation (BIO-FGD). A flue gas desulphurisation installation can comprise an absorber 1 , an anaerobic reactor 2 , an aerobic reactor 3 , and a sulphur separator 4 . In the absorber 1 , sulphur dioxide is absorbed from the flue gas byr the scrubbing liquid, which is usually slightly alkaline:
NaOH+SO 2 →NaHSO 3 (1)
A part of the sulphite is oxidised to sulphate as a result of the presence of oxygen in the flue gas:
NaHSO 3 +½ O 2 +NaOH→Na 2 SO 4 +H 2 O (1a)
In the anaerobic reactor 2 , the sulphite and sulphate in the spent scrubbing liquid are reduced to sulphide by means of a hydrogen suppls, in the presence of the bacteria of the invention:
NaHSO 3 +3H 2 →NaHS+3H 2 O (2)
Na 2 SO 4 +4H 2 →NaHS+3H 2 O+NaOH (2a)
In the aerobic reactor 3 , the sulphide is oxidised by sulphide-oxidising bacteria, generally belonging to the colourless sulphur bacteria, such as Thiobacillus, Thiomicrospira, Sulfolobus and Thermothrix. Preferably the oxygen supply in the aerobic reactor is controlled so as to maximise the formation of elemental sulphur rather than sulphate:
NaHS+½ O 2 →S°+NaOH (3)
The alkalinity, used in the absorber unit 1 , is recovered in the aerobic stage and no alkaline chemicals are consumed in the overall process:
SO 2 +3H 2 +½ O 2 →S°+3H 2 O (1+2+3)
After the aerobic reactor 3 , the elemental sulphur is decanted or filtered off in a separator 4 , and the clarified effluent is reused as a scrubbing liquid.
An installation of the type described above is diagrammatically depicted in FIG. 1 : the scrubber 1 has a (flue) gas inlet 11 , a gas outlet 12 , a liquid inlet 13 and a liquid outlet 14 ; the anaerobic reactor 2 has an inlet 21 for hydrogen or another electron donor, a gas outlet 22 , a liquid inlet 23 connected to 14 and a liquid outlet 24 ; the aerobic reactor 3 has a controllable air inlet 31 , a gas outlet 32 , a liquid inlet 33 connected to 24 and a liquid outlet 34 ; the separator 4 has liquid inlet 41 , solid (slurry) outlet 42 , and a clarified liquid outlet 43 with return line 45 connected to scrubber inlet 13 and having a surplus liquid outlet 44 .
In addition to the components described thus far, the installation may also comprise a second anaerobic reactor 5 , shown in FIG. 2, wherein part of the clarified effluent in 45 , which still contains sulphate and thiosulphate, is treated with sulphur-reducing bacteria in the presence of hydrogen, and the effluent of the second anaerobic reactor is fed to the aerobic reactor 4 . The second anaerobic reactor 5 has an inlet 51 for hydrogen or another electron donor, a gas outlet 52 , a liquid inlet 53 connected to 45 and a liquid outlet 54 leading to 33 . The optimum flow ratio of clarified effluent (flow in 53 : flow in 13 ) will depend on the composition of the flue gas and on the dimensions of the reactor; it can be e.g. from 10:90 to 30:70, in particular about 15:85.
The second anaerobic reactor 5 may also contain bacteria according to the invention. In a preferred embodiment, sulphite is reduced with free cells in the first anaerobic reactor 2 , whereas in the second anaerobic reactor 5 sulphate and thiosulphate are reduced with biomass retention on a carrier; thus, sulphite and sulphate are reduced separately in two anaerobic reactors.
Apart from flue gas scrubbing liquids, various water effluents can be treated using the process of the invention, for example ground water, mining effluent, industrial waste water, for example originating from the printing industry, metallurgy, leather, rubber, viscose and fibre industry, paper industry and polymer industry, and wash water of flue gas treatment plants.
If the bacteria are used in waste water containing organic matter, no additional electron donor may be necessary. Otherwise, an electron donor should be added, which may be hydrogen as illustrated above, but also carbon monoxide and organic compounds such as fatty acids (acetic acid), alcohols (methanol, ethanol), sugars, starches and organic waste. If necessary, nutrient elements are also added in the form of nitrogen, phosphate and trace elements.
The process according to the invention can be used for a wide variety of sulphur compounds: in the first place, the method is particularly suitable for the removal of inorganic sulphate and sulphite. Further possible compounds are other inorganic sulphur compounds such as thiosulphate, tetrathionate, dithionite, elementary sulphur and the like. Organic sulphur compounds, such as alkanesulphonates, dialkyl sulphides, dialkyl disulphides, mercaptans, sulphones, sulphoxides, carbon disulphide and the like can also be removed from water by the process according to the invention.
The sulphide concentration in the effluent of the anaerobic reactor is usually at least 500 mg/l, in particular it can be 800-1000 mg/l, or even higher.
The anaerobic treatment can preferably be carried out at an elevated temperature, in particular at a temperature of 43-75° C., especially at a temperature of 45-70° C. The elevated temperature can be employed continuously, for example when an inexpensive energy source is available, as in the case of hot flue gases and/or a warm wash liquid.
The product from the process according to the invention is, if post-oxidation is applied, elementary sulphur, which can be separated off simply from water, for example by settling, filtration, centrifuging or flotation, and can be re-used, for example for the production of sulphuric acid.
EXAMPLES
Example 1
A reactor of 6.5 l was run under anaerobic conditions at 50° C., pH 7.0 and conductivity of 20-25 mS/cm. The reactor was inoculated with 500 ml of crushed granular sludge of conventional mesophilic SRB (origin: paper waste water treatment plant Parenco, NL and mining waste water treatment plant Budelco, NL). The reactor was supplied with sulphite, 2500 mg/l (≈3940 mg Na 2 SO 3 /l) and sulphate, 750 mg/l (≈1110 mg Na 2 SO 4 /l), nutrient flow 1800 ml/h and with hydrogen, 6000 ml/h, as the electron donor. The sulphide concentration was never higher than 500 mg S 2− /l. The reactor was run for one year, so the sludge was adapted to high temperature.
After inoculation with KT7, 250 ml, the sulphide concentration increased to 600/700 mg S 2− /l in 1 week and to 800-1000 mg S 2− /l in 7 weeks. No more sulphide could be formed because of the composition of the influent. Physiological and morphological analysis of bacterial samples showed that the strain responsible for the higher sulphide concentration was the KT7 strain.
Example 2
A reactor of 6.5 l was run under anaerobic conditions at 50° C., pH 7.0.and conductivity of 20-25 mS/cm. The reactor was supplied with sulphite/sulphate as in Example 1. Nutrient flow was up to 300 ml/h and hydrogen flow was up to 1300 ml/h. Acetate (100 mg/l) and yeast (1 mg/l) were present as organic carbon sources. The reactor was inoculated with KT7 (0.54 g) from the start, without other sludge.
After some days, the sulphide concentration reached 800-1000 mg/l; no more sulphide could be formed because of the composition of the influent. After this, the acetate and yeast were left out of the medium (supply discontinued). After another 2-3 weeks the sulphide concentration again reached 800-1000 mg/l.
Example 3
Example 2 was repeated, with the exception that the reactor did not contain any acetate or yeast. Some weeks after inoculation with KT7, the sulphide concentration reached 800-1000 mg/l.
Example 4
In a pilot desulphurisation plant at the Power Station of Geertruidenberg (NL), the anaerobic, hydrogen-fed reactor had a volume of 5.5 m 3 , pH 7-7.5, conductivity 10-30 mS/cm. Four kg of SO 2 per h was absorbed in the gas scrubber and fed to the anaerobic reactor in the form of sulphite and sulphate. The reactor was operated at 50° C. The reactor was started with a mixture of bacteria, largely conventional SRB (gas desulphurisation and paper waste treatment) and partly KT7 bacteria (<1%).
The sulphide concentration reached 1500 mg S 2− /l after two weeks. The sulphide production reached a level of 15 kg/m 3 .day. After six months, KT7 was still dominant in the reactor. | A new sulfur-reducing bacterium denoted as KT7 is described. It is a low-GC Gram-positive bacterium related to the genus Desulfotomaculum, capable of reducing sulfite and sulfate to sulfide, having an optimum growth at a temperature between 48 and 70° C. at a pH of between 5 and 9 and at a conductivity of the liquid medium between 0 and 40 mS/cm. It can be used in a process for removing sulfur compounds from water, wherein the sulfur-containing water is subjected to anaerobic treatment with the new sulfur-reducing bacteria, with the addition of an electron donor. The sulfur-containing water can be spent scrubbing liquid from a flue gas desulfurization step. | 2 |
FIELD OF THE INVENTION
The present invention relates to an apparatus for anchoring surgical suture to bone. More specifically, the present invention relates to a threaded suture anchor formed of polyether-ether ketone (PEEK) having an internal suture loop for receiving one or more strands of suture to anchor the suture to bone during arthroscopic surgery.
BACKGROUND OF THE INVENTION
When soft tissue tears away from bone, reattachment becomes necessary. Various devices, including sutures alone, screws, staples, wedges, and plugs have been used in the prior art to secure soft tissue to bone.
Recently, various types of threaded suture anchors have been developed for this purpose. Some threaded suture anchors are designed to be inserted into a pre-drilled hole. Other suture anchors are self-tapping.
U.S. Pat. No. 4,632,100 discloses a cylindrical threaded suture anchor. The suture anchor of the '100 patent includes a drill bit at a leading end for boring a hole in a bone, followed by a flight of threads spaced from the drill bit for securing the anchor into the hole created by the drill bit.
U.S. Pat. No. 5,370,662 discloses a suture anchor having threads which extend to the tip of the anchor. U.S. Pat. No. 5,156,616 discloses a similar suture anchor having an axial opening for holding a knotted piece of suture.
All of the above-noted suture anchors include structure for attaching the suture to the anchor. U.S. Pat. No. 4,632,100, for example, discloses a press-fitted disc and knot structure which secures the suture to the anchor. In other suture anchors, such as those disclosed in U.S. Pat. No. 5,370,662, the suture is passed through an eyelet located on the proximal end of the anchor. In the case of a bioabsorbable suture anchor, the suture may be insert molded into the anchor, as disclosed in U.S. Pat. No. 5,964,783. However, the materials used to make such suture anchors can impose limitations on their use. For example, suture anchors made of metal or certain polymers are not radiolucent or radioopaque and thus are not visible on magnetic resonance imaging (“MRI”) scans. In addition, such suture anchors may not be revisable once implanted in the bone.
Problems can also arise if the structure for attaching the suture fails, allowing the suture to become detached from the anchor. Also, the suture often is exposed to abrasion or cutting by sharp or rough areas along the walls of the bone canal into which the anchor is inserted.
Moreover, the eyelet or, in the case of U.S. Pat. No. 4,632,100, the axial opening for receiving the disc to which the suture is knotted, is formed as part of the drive head of the known suture anchors. Combining these two functions in one structure often tends to weaken the drive head.
In addition, various other modifications to the drive head often are employed in connection with suture attachment. For example, recessed grooves may be formed on opposite sides of the drive head to receive and protect the suture from abrasive areas of the suture anchor tunnel or to facilitate mating between the anchor to the driver. In such cases, the drive head often must be made of a larger diameter to recover the mechanical strength lost from the removal of material relating to the suture-attachment or suture-protection modifications.
Further, the prior art suture anchors having eyelets extending from the proximal ends require countersinking of the eyelet below the bone surface to avoid having the patient's tissue abrade against the exposed eyelet. As a result, suture attached to the eyelet is vulnerable to abrasion by the bony rim of the countersunk hole into which the suture anchor is installed. In addition, in biodegradable suture anchors, the suture eyelet can degrade rapidly, causing the suture to become detached from the anchor prematurely.
Accordingly, there is a need for a threaded suture anchor to which suture is secured effectively so as to prevent detachment of the suture. It is further desirable for such suture anchors to have eyelets that will not abrade tissue and which do not require countersinking. In addition, a need exists for a suture anchor or implant formed by a material which is visible on MRI scans and is revisable following implantation.
BRIEF SUMMARY OF THE INVENTION
The suture anchor of the present invention overcomes the disadvantages of the prior art discussed above by providing a threaded suture anchor having a suture loop disposed inside the body of the suture anchor. In one embodiment, the suture anchor is formed from a material comprising polyether-etherketone (“PEEK”). The advantages of PEEK are described in a white paper entitled, “New Materials in Sports Medicine,” Arthrex, Inc. 2005, the disclosure of which is herein incorporated by reference.
The proximal end surface of the threaded suture anchor of the present invention is preferably smooth and rounded to minimize suture abrasion, while the distal portion of the anchor is tapered to an elongated point to enable the anchor to be self-tapping. The proximal end portion of the suture anchor body has a hexagonally shaped opening to accept a hexagonal drive head.
The internal suture loop extends through a substantial length of the anchor body with the ends of the suture loop secured onto the distal end portion of the anchor and the proximal end of the loop being flush with or recessed just below the plane across the proximal face of the anchor.
Advantageously, suture attached to the anchor through the suture loop exits the suture anchor through a central bore in the anchor, which prevents suture abrasion by the wall of the bone tunnel into which the anchor is inserted.
Other features and advantages of the present invention will become apparent from the following description of the invention, which refers to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a first preferred embodiment of a suture anchor according to the present invention;
FIG. 2 is a side elevational view of the suture anchor shown in FIG. 1 ;
FIG. 3 is a longitudinal sectional view of the suture anchor shown in FIG. 2 through the plane 3 - 3 indicated therein;
FIG. 4 is a cross sectional view of the suture anchor of FIG. 1 showing the internal suture loop therein, and having suture strands attached to the suture anchor through the internal suture loop.
FIG. 5 is a cross sectional view through the suture anchor and suture loop of FIG. 4 through the plane 6 - 6 indicated therein.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 2 illustrate a suture anchor according to a first preferred embodiment of the present invention, indicated generally by reference numeral 110 . In the preferred embodiment, body 108 of anchor 110 has a length of about 0.55 in., a major diameter “a” of about 0.21 in., and a minor diameter “b” of about 0.14 in. Suture anchor body 108 generally tapers to a narrow point 114 at the distal end thereof. In particular, the major diameter of the anchor body is generally constant along about two-thirds of the length of the body, whereupon the diameter of the anchor then tapers to a relatively sharp point, e.g., approximately 16 degrees. In one embodiment, the relatively sharp distal tip of anchor 110 enables the anchor to be installed without having to first drill a hole in the bone where the anchor 110 is to be installed.
Although such tapering is preferred, suture anchor 110 may be formed to have a less tapered shape, or even cylindrical shape, to accommodate different preferences of the surgeon and/or the application of the suture anchor. For example, the tapered distal end of the anchor may be formed to be more blunt, in which case it is necessary to provide a pre-formed hole in the bone prior to insertion of the suture anchor.
A continuous thread 116 wraps around the body 108 in a clockwise direction, as shown. Anchor 110 has about six flights of thread, with the angle of the proximal surface 128 of each thread being approximately one-third the angle of the distal surface 130 of each thread relative to the horizontal direction perpendicular to the longitudinal axis of the anchor, e.g., 15 degrees versus 45 degrees.
As can be seen more clearly with reference to FIG. 3 , the proximal end portion of the anchor has a hexagonally shaped bore 132 having an opening 120 at the proximal end of anchor body 108 and extending into the anchor body approximately one-fourth of the length thereof. Prior art anchors have sharp edges around the drive opening, which is problematic in that sutures passing through the central opening at the proximal end of the anchor can be abraded by the sharp edges, thereby compromising the strength of the sutures. In one embodiment of the suture anchor of the present invention, the peripheral edges defining hexagonally shaped opening 120 is smooth and rounded outwardly with no sharp edges. Preferably, the opening 120 forms a slight lip curving around the diameter of the bore 132 . Thus, sutures threaded through the anchor 110 , as will be discussed below, will not become frayed upon being pressed or rubbed against the anchor at the proximal opening 120 .
A cylindrical bore 136 having a diameter smaller than that of the hexagonally shaped bore 132 extends from the distal end of the hexagonally shaped bore 132 to a position roughly one quarter along the length of anchor body 108 . The transition between hexagonally shaped bore 132 and cylindrical bore 136 forms an annular shoulder 134 , against which the distal end of a hex driver abuts when inserted into the hexagonally shaped bore 132 to drive the anchor into bone.
Two longitudinal passageways 126 are formed in anchor body 108 distally to the cylindrical bore 136 , extending from the distal end of bore 136 to two corresponding apertures 118 formed opposite to each other in an offset manner through the angled distal portion of suture anchor 110 . Referring to the cross-sectional view shown in FIG. 5 , the preferred distance “c” between the centers of the two passageways 126 is about 0.55 in.
Apertures 118 each have an inner opening 117 defining the exit from the respective passageway 126 , and widen to a larger, exterior opening 119 along the radial surface of anchor body 108 . As can be seen in FIG. 2 , apertures 118 are disposed between the threads 116 around anchor body 108 . Due to the shape of apertures 118 and the angle at which apertures 118 intersect passageways 126 , inner openings 117 are slightly oblong and may have an angle along the periphery thereof. Preferably, the peripheral edges defining the inner openings 117 of the suture anchor are smoothed and rounded (e.g., during the manufacturing process) so as to not abrade the suture knots which will be affixed therein (described below).
An eyelet formed of a loop of suture 122 is disposed inside the body of suture anchor 110 . The ends of the suture strand forming the loop can be threaded through the longitudinal passageways 126 from the proximal opening 120 and pass into the apertures 118 . Threading the ends of the suture through the passageways 126 and the apertures 118 may be facilitated by coating the ends of the suture (having a length longer than the length of the passageways 126 ) with a stiffening agent.
The proximal-most surface of the suture loop 122 is flush with or slightly recessed from the proximal opening 120 , so that the suture loop does not project outside the body 108 of suture anchor 110 . Preferably, the suture loop 122 is recessed between 0.05 to 0.14 in. from the plane across the suture anchor 110 at the proximal opening 120 thereof, as measured from the underside of the proximal-most point of the loop 122 . The underside position corresponds to the depth into the bore 132 at which a suture strand inserted through the loop 122 would be attached to anchor 110 .
To secure the suture loop onto anchor body 108 , the ends of suture loop 122 are each tied in a knot 125 , e.g., an overhand knot, and sealed with a biocompatible adhesive to permanently affix the knot. As illustrated in FIG. 4 , knots 125 are then respectively inserted into the apertures 118 so that the knots are substantially entirely fitted within the space of the apertures 118 . As shown in FIG. 4 , knots 125 are asymmetrically disposed in their respective apertures 118 relative to a most proximal end 113 of the anchor body 108 . The smaller diameter of inner openings 117 of apertures 118 prevent the knots 125 from being pulled through into the interior of the anchor 110 . Affixed in this manner, suture loop 122 has a pullout strength of 45 lbs. from the suture anchor 110 .
Preferably, the suture anchor 110 is formed from a material comprising PEEK. A suture anchor formed from a material comprising PEEK has several advantageous properties. First, PEEK is radiolucent. PEEK does not contain metal and therefore no metallic scatter occurs during magnetic resonance imaging (MRI) scans.
In addition, suture anchors formed by PEEK have significantly reduced notch sensitivity resulting in a more stable and resilient suture anchor. The term “resilient” as used herein is not meant to imply that PEEK material is deformable and recovers its size and shape after deformation, rather is intended to mean that PEEK is capable of withstanding shock and other outside forces without deterioration. Specifically, the term “resilient” is taken from the PEEK-Optima Polymer brochure of Invibio Ltd., UK, 2004, where it is stated that PEEK is “resilient and enduring” in the sense that PEEK is “characterized by its high strength. extreme resistance to hydrolysis and resistance to the effects of ionizing radiation. Therefore, PEEK-OPTIMA can be repeatedly sterilized . . . without significant deterioration of mechanical properties.” The construction of an anchor body formed from a material comprising PEEK provides both stable fixation and revisability. Previously available suture anchors may require “wings” or “arms” to provide fixation. In contrast, the threading of the PEEK unibody construction shown in FIGS. 1-5 provide stable fixation without requiring additional structural features. Furthermore, PEEK suture anchors are revisable, for example, by drilling out the anchor.
The mechanical properties of PEEK closely match the mechanical properties of bone: tensile yield strength, shear strength, and modulus. These properties are not significantly degraded by gamma-irradiation, steam-sterilization (water environment), or oxidation (aging). The material is also resistant to heat and requires no special accommodations for shipping and handling.
Preferably, the material forming the suture loop 122 is a #5 USP braided polyester suture or #2 FiberWire™, a high strength suture formed of a braid of polyester and ultrahigh molecular weight polyethylene, coated with silicone, and sold by Arthrex, Inc. of Naples, Fla. However, any suitable coated or uncoated suture material can be used with the suture anchor of the invention.
The suture anchor according to the present invention need not be formed as a threaded device, but can also be formed as a tap-in type anchor. Also, the measurements, angles and ratios between the dimensions of the suture anchor may be varied from those described above so as to be suitable for the conditions and applications in which the suture anchor is to be used.
In manufacturing the suture anchor 110 in accordance with the present invention, the anchor body 108 is machined, with the bores, passageways and apertures described above either being formed during the machining process or formed afterwards. If necessary, the distal tip 114 of the anchor 110 is trimmed to the desired length and the surfaces of the anchor are polished to the desired finish. Alternatively, the anchor body 108 can be cast in a die with the bores, passageways and apertures described above either being formed during the casting process or formed afterwards.
Preferably, the suture anchors according to the present invention are distributed to surgeons with one or more strands of suture 138 already threaded through the suture loop. Such sutures attached to the suture anchor through the internal suture loop must be able to slide smoothly through the slightly recessed loop. Sutures suitable for use in conjunction with the suture anchor and internal suture loop discussed herein include #2 FiberWire™ and #2 braided polyester. If more than one suture strand is provided through the suture loop, each strand is preferably a different color, e.g., green, white, blue, etc., or may be provided with color contrasting strands.
Optionally, or if it becomes necessary due to the pre-threaded suture strands being accidentally removed from the suture loop, the user may be required to thread or re-thread the suture strands through the suture loop. In this case, threading a strand of suture through the suture loop may be facilitated if the ends of the suture strand are coated with a stiffening agent. Alternatively or additionally, a tool may be used to thread the suture strands and/or grasp the end of the suture after passing through the suture loop.
As mentioned above, the suture anchor of the present invention may be installed in the bone without the need to pre-drill a hole in the bone. The suture anchor is installed using a driver having a shaft having a hexagonal cross-section for at least a length equal to the length of the hexagonal bore 132 , 232 from proximal opening 120 , 220 to the shoulder 134 , 234 inside the anchor 110 , 210 . The driver has a cannula extending through the entire length thereof, with openings at the proximal and distal ends thereof. The outer diameter of the hexagonal shaft can be sized to fit inside the hexagonal bore in the anchor so as to be enabled to drive the same.
With the desired number of suture strands threaded through the suture loop in the suture anchor, the ends of the suture strands are threaded through the cannula in the hex driver from the distal end thereof and exiting from the proximal opening thereof. The distal end of the hexagonal shaft of the driver can be inserted into the proximal end of the anchor while the suture loop is inserted into the distal end opening of the driver. With the distal end of the driver abutting shoulder 134 and the anchor positioned at the location at which it is to be installed, the hex driver is rotated to drive the anchor into the bone until the proximal surface of the anchor is flush with the surface of the bone.
Since it is not necessary for the proximal end of the anchor to be countersunk below the bone surface to prevent tissue abrasion by an exposed suture loop, as is required with prior art devices, the suture anchor of the present invention does not need to be inserted as far as the prior art anchors, while also avoiding abrasion of the sutures by the rim of the bone.
The suture anchor of the present invention provides greater pull-out strength of the suture loop than prior suture anchors. In addition, the suture loop of the present invention, being disposed inside the suture anchor, is protected from abrasion and degradation.
Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. Therefore, the present invention is to be limited not by the specific disclosure herein, but only by the appended claims. | A threaded suture anchor formed of a material comprising polyether-ether ketone (PEEK) has a suture loop that is disposed internally within the suture anchor. The suture loop can extend through a substantial length of the anchor body with the ends of the suture loop secured at the distal end of the anchor and the proximal end of the loop being flush with or recessed just below the proximal surface of the proximal end of the anchor. The anchor body can be threaded and have a tapered distal portion. | 0 |
This application claims benefit from prior Provisional Application Serial No. 60/135,290, filed May 21, 1999.
This invention relates to an apparatus and method for the construction and utilization of molecular deposition domains. More specifically, this invention is a method for the construction and utilization of molecular deposition domains into a high density molecular array for identifying and characterizing molecular interaction events.
BACKGROUND
Interactions between molecules is a central theme in living systems. These interactions are key to myriad biochemical and signal transduction pathways. Messages from outside a cell travel along signal transduction pathways into the cell's nucleus, where they trigger key cellular functions. Such pathways in turn dictate the status of the overall system. Slight changes or abnormalities in the interactions between biomolecules can effect the biochemical and signal transduction pathways, resulting in inappropriate development, cancer, a variety of disease states, and even cell senescence and death. On the other hand, it can be extremely beneficial to develop reagents and effectors that can inhibit, stimulate, or otherwise effect specific types of molecular interactions in biochemical systems; including biochemical and signal transduction pathways. Reagents and effectors that effect nucleus interactions may often become very powerful drugs which can be used to treat a variety of conditions.
Current Technology
Several recent studies have shown that a scanning probe microscope “SPM” may be used to study molecular interactions by making a number of measurements. The SPM measurements may include changes in height, friction, phase, frequency, amplitude, and elasticity. The SPM probe can even perform direct measurements of the forces present between molecules situated on the SPM probe and molecules immobilized on a surface. For example, see Lee, G. U., L. A. Chrisey, and R. J. Colton, Direct Measurement of the Forces Between Complementary Strands of DNA . Science, 1994. 266: p. 771-773; Hinterdorfer, P., W. Baumgartner, H. J. Gruber, and H. Schindler, Detection and Localization of Individual Antibody antigen Recognition Events by Atomic Force Microscopy , Proc. Natl. Acad. Sci., 1996. 93: p. 3477-3481; Dammer, U., O. Popescu, P. Wagner, D. Anselmetti, H.-J. Guntherodt, and G. N. Misevic, Binding Strength Between Cell Adhesion Poteoglycans Measured by Atomic Force Microscopy . Science, 1995. 267: p. 1173-1175; Jones, v. et al. Microminiaturized Immunoassays Using Atomic Force Microscopy and Compositionally Patterned Antigen Arrays , Analy. Chem., 1998 70(7): p. 1233-1241; and Rief, M., F. Oesterhelt, B. Heymann, and H. E. Gaub, Single Molecule Force Spectroscopy on Polysaccharides by Atomic Force Microscopy , Science, 1997. 275: p. 1295-1297. The above studies illustrate that it is possible to readily and directly measure the interaction between and within virtually all types of molecules by utilizing an SPM. Furthermore, recent studies have shown that it is possible to use direct force measurement to detect changes in molecular complex formation caused by the addition of a soluble molecular species. A direct force measurement may elucidate the effect of soluble molecular species on the interaction between a molecular species on an SPM probe and a surface.
Molecular Arrays
The ability to measure molecular events in patterned arrays is an emerging technology. The deposition material can be deposited on a solitary spot or in a variety of sizes and patterns on the surface. The arrays can be used to discover new compounds which may interact in a characterizable way with the deposited material. Arrays provide a large number of different test sites in a relatively small area. To form an array, one must be able to define a particular site at which a deposition sample can be placed in a defined and reproducible manner.
There are four approaches for building conventional molecular arrays known in the art. These prior art methods include 1) mechanical deposition, 2) in situ photochemical synthesis, 3) “ink jet” printing, and 4) electronically driven deposition. The size of the deposition spot (or “domain”) is of particular importance when utilizing an SPM to scan for molecular recognition events. Current SPM technology only allows a scan in a defined area. Placing more domains in this defined area allows for a wider variety of molecular interaction events to be simultaneously tested.
Mechanical deposition is commonly carried out using a “pin tool” device. Typically the pin tool is a metal or similar cylindrical shaft that may be split at the end to facilitate capillary take up of liquid. Typically the pin is dipped in the source and moved to the deposition location and touched to the surface to transfer material to that domain. In one design the pin tool is loaded by passing through a circular ring that contains a film of the desired sample held in the ring by surface tension. The pin tool is washed and this process repeated. Currently, pin tool approaches are limited to spot sizes of 25 to 100 microns or larger. The spot size puts a constraint on the maximum density for the molecular deposition sites constructed in this manner. A need exists for a method that allows for molecular domains of smaller dimensions to be deposited.
In situ photochemical procedures allow for the construction of arrays of molecular species at spatial addresses in the 1-10 micron size range and larger. In situ photochemical construction can be carried out by shining a light through a mask. Photochemical synthesis occurs only at those locations receiving the light. By changing the mask at each step, a variety of chemical reactions at specific addresses can be carried out. The photochemical approach is usually used for the synthesis of a nucleic acid or a peptide array. A significant limitation of this approach is that the size of the synthetic products is constrained by the coupling efficiency at each step. Practically, this results in appreciable synthesis of only a relatively short peptide and nucleic acid specimen. In addition, it becomes increasingly improbable that a molecule will fold into a biologically relevant higher order architecture as the synthetic species becomes larger. A need exists for an alternative method for deposition of macromolecular species that will preserve the molecular formation of interest in addition to avoiding the cost of constructing the multiple masks used in this method.
Ink jet printing is an alternative method for constructing a molecular array. Ink jet printing of molecular species produces spots in the 100 micron range. This approach is only useful for printing a relatively small number of species because of the need for extensive cleaning between printing events. A key issue with ink jet printing is maintenance of the structural/functional integrity of the sample being printed. The ejection rate of the material from the printer results in shear forces that may significantly compromise sample integrity. A need exists for a method that will retain the initial structure and functional aspects of the deposition material and that will form smaller spots than are possible with the above ink jet method.
Electronic deposition is yet another method known for the construction of molecular arrays. Electronic deposition may be accomplished by the independent charging of conductive pads, causing local electrochemical events which lead to the sample deposition. This approach has been used for deposition of DNA samples by drawing the DNA to specific addresses and holding them in a capture matrix above the address. The electronic nature of the address can be used to manipulate samples at that location, for example, to locally denature DNA samples. A disadvantage of this approach is that the address density and size is limited by the dimensions of the electronic array.
A need exists for a molecular deposition technique that will allow for smaller deposition spots (domains). Smaller deposition domains allow for an array to be constructed with a greater density of domains. More domains further allow for a wider variety in the deposition material to be placed on the same array, allowing a user to search for more molecular interaction events simultaneously.
A further need exists for the ability to place these spots at a defined spatial address. Placing the domains at defined spatial addresses allows the user to know exactly what deposition material the SPM is scanning at any given time.
Furthermore, a need exists for a method to make deposition domains with large molecular weight samples that also retains the desired chemical formation. Finally, a need exists for the efficient construction of these molecule domains into an array.
Molecular Detection
All of the above examples are further limited because they require some type of labeling of the deposition sample for testing. Typical labeling schemes may include fluorescent or other tags coupled to a probe molecule. In a typical molecular event experiment, an array of known samples, for example DNA sequences, will be incubated with a solution containing a fluorescent indicator. In the DNA example this would be fluorescently or otherwise labeled nucleic acids, most often a single stranded DNA of an unknown sequence. Specific sequence elements are identified in the DNA sample by virtue of the hybridization of the label to addresses containing known sequence elements. This process has been used to screen entire ensembles of expressed genes in a given population of cells at a particular time or under a particular set of conditions. Other labeling procedures have also been employed, including RF (radio frequency) labels and magnetic labels. These methods are less frequently used, however, than the fluorescent label methods desired above. All of these labels hinder experiments with extra steps, reagents, and in some cases, risk.
Other methods for the detection of the interactions of molecules on a molecular array include inverse cyclic voltametry, capacitance or other electronic changes, radioactivity (such as with isotopes of phosphorous), and chemical reactions. In virtually all cases, some form of labeling of the probe molecule that is added to the array is required. This is a significant limitation of current arrays. A need exists for a method that does not require this extra labeling step.
Scanning Probe Microscopy
A wide variety of SPM instruments are capable of detecting optical, electronic, conductive, and other properties. One form of SPM, the atomic force microscope (AFM), is an ultra-sensitive force transduction system. In the AFM, a sharp tip is situated at the end of a flexible cantilever and scanned over a sample surface. While scanning, the cantilever is deflected by the net sum of the attractive and repulsive forces between the tip and sample. If the spring constant of the cantilever is known, the net interaction force can be accurately determined from the deflection of the cantilever. The deflection of the cantilever is usually measured by the reflection of a focused laser beam from the back of the cantilever onto a split photodiode, constituting an “optical lever” or “beam deflection” mechanism. Other methods for the detection of cantilever deflection include interferometry and piezoelectric strain gauges.
The first AFMs recorded only the vertical displacements of the cantilever. More recent methods involve resonating the tip and allowing only transient contact, or in some cases no contact at all, between it and the sample. Plots of tip displacement or resonance changes as it traverses a sample surface are used to generate topographic images. Such images have revealed the three dimensional structure of a wide variety of sample types including material, chemical, and biological specimens. Some examples of the latter include DNA, proteins, chromatin, chromosomes, ion channels, and even living cells.
In addition to its imaging capabilities, the AFM can make extremely fine force measurements. The AFM can directly sense and measure forces in the microNetwon (10 −6 ) to picoNewton (10 −12 ) range. Thus, the AFM can measure forces between molecular pairs, and even within single molecules. Moreover, the AFM can measure a wide variety of other forces and phenomena, such as magnetic fields, thermal gradients and viscoelasticity. This ability can be exploited to map force fields on a sample surface, and reveal with high resolution the location and magnitude of these fields, as in, for example, localizing complexes of interest located on a specific surface.
Direct Force Measurement
To make molecular force measurements, the AFM probe is functionalized with a molecule of interest. This bio- or chemi-active probe is then scanned across the surface of interest. The molecule tethered to the probe interacts with the corresponding molecule or atoms of interest on the surface being studied. The interactions between the molecule fnctionalized on the probe and the molecules or atoms on the surface create minute forces that can be measured by displacement of the probe. The measurement is typically displayed as a force vs. distance curve (“force curve”).
To generate a force curve, the tip or sample is cycled through motions of vertical extension and retraction. Each cycle brings the tip into contact with the sample, then pulls the tip out of contact. The displacement of the cantilever is zero until the extension motion brings the tip into contact with the surface. Then the tip and sample are physically coupled as the extension continues. The physical coupling is the result of hard surface contact (Van der Waals interactions) between the probe and the surface. This interaction continues for the duration of the extension component of the cycle. When the cycle is reversed and the tip retracted, the physical contact is broken. If there is no attractive interaction between the tip and sample the tip separates from the sample at the same position in space at which they made contact during extension. However, if there is an adhesive interaction between the tip and sample during retraction, the cantilever will bend past its resting position and continue to bend until the restoring force of the cantilever is sufficient to rupture the adhesive force.
In the case of extendable molecular interactions, the distance between the tip and surface at which a rupture is observed corresponds to the extension length of the molecular complex. This information can be used to measure molecular lengths and to measure internal rupture forces within single molecules. In a force curve an adhesive interaction is represented by an “adhesion spike.” Since the spring constant of the probe is known, the adhesive force (the unbinding force) can be precisely determined. Upon careful inspection of a typical adhesion spike, many small quantal unbinding events are frequently seen. The smallest unbinding event that can be evenly divided into the larger events can be interpreted as representing the unbinding force for a single molecular pair.
The spectra produced by these binding events will contain information about the coupling contacts holding the molecules together. Thus, it is possible to interpret the signature generated by a mechanical denaturation experiment with regard to the internal structure of the molecule. An SPM can further utilize height, friction, and elasticity measurements to detect molecular recognition events. Molecular recognition events are when one molecule interacts with another molecule or atom in, for example, an ionic bond, a hydrophobic bond, electrostatic bond, a bridge through a third molecule such as water, or a combination of these methods.
In an alternative approach, the AFM probe is oscillated at or near its resonance frequency to enable the measurement of recognizance parameters, including amplitude, frequency and phase. Changes in the amplitude, phase, and frequency parameters are extremely sensitive to variations in the interaction between the probe and the surface. If the local elasticity or viscosity of the surface changes as a result of a molecular recognition event, there is a shift in one or more of these parameters.
Others have reported using AFMs and STMs for the deposition of materials. One report is from Chad Mirkin (Northwestern University) in which he used an AFM to write nanometer scale molecule features with short alkane chains. Hong, S., J. Zhu, and C. A. Mirkin, Multiple Ink Nanolithography: Toward A Multiple - Pen Nano - Plotter , Science. 1999, p. 523-525. A need exists, however, for a molecular domain deposition method that is not limited to short chain length molecules. A need exists for a method for depositing longer chain length macromolecules that does not change or hinder the formation of the deposited molecule.
A need exists for an improved apparatus and method for utilization in the detection of molecular interaction events. A need exists for a method for the creation of small, sub-micron scale molecular domains at defined spatial addresses. This apparatus should enable the user to test for a variety of different types of events in a spatially and materially efficient manner by facilitating the deposition, exposure, and scanning of molecular domains to detect a resultant molecular interaction event. Furthermore, an apparatus is needed that enables the placement of a large number of molecular domains in a relatively small area.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of the method of forming a deposition domain.
FIG. 2 is a block diagram of the method of forming an array and utilizing the same.
FIG. 3 is a side view of the deposition device used with the present invention.
FIG. 4 is a side view of the deposition device and the microspheres of the present invention.
FIG. 5 is a side view of a microsphere attached to a deposition device.
FIG. 6 is an alternative attachment of the microsphere to the deposition device.
FIG. 7 a is a side view of the deposition device before loading the deposition material on it.
FIG. 7 b is a side view of a capillary bridge between the deposition material and the microsphere during loading of the deposition material
FIG. 8 a is a side view of a microsphere with deposition material loaded on the microsphere.
FIG. 8 b is a side view of a capillary bridge between the microsphere and a surface druring the deposition of a deposition domain.
FIG. 9 is a side view of a deposition domain on an array just after the microsphere has been withdrawn.
FIG. 10 is a perspective view of an array of the present invention.
FIG. 11 is an outline view of an example scan of an array after exposure to a target medium.
SUMMARY
A method for the construction of a molecular deposition domain on a surface, comprising, providing a surface, depositing a deposition material on a deposition device, and depositing the deposition material on the surface using said deposition device, forming a molecular deposition domain smaller than one micron in total area.
Another embodiment comprises method for constructing an array of molecular deposition domains including the steps of providing a surface, providing an at least one deposition material, depositing a first deposition material on a deposition device, depositing the first deposition material on the surface in a known position, forming a first molecular deposition domain smaller than one micron in total area, cleaning the deposition device, and repeating the above steps with an at least one other deposition material, creating an array of two or more deposition domains on said surface.
Yet another embodiment comprises a method for detecting a target sample, the method comprising, forming a molecular array on a surface, the molecular array including an at least one molecular deposition domain, said at least one molecular deposition domain smaller than one micron in total area, exposing the surface to a sample medium, the sample medium containing one or more target samples which cause a molecular interaction event in one or more of the at least one deposition domain, and scanning the surface using a scanning probe microscope to detect the occurrence of the molecular interaction event caused by the target sample.
A still further embodiment comprises a molecular array for characterizing molecular interaction events, comprising a surface, and an at least one molecular deposition domain deposited on said surface wherein the spatial address of the domain is less than one micron in area.
Another embodiment comprises a method for the processing of multiple arrays including forming an array in a substrate, the array comprising a plurality of deposition domains formed of a deposition material, exposing the array to one or more materials which contain an at least one sample molecule that causes a molecular interaction event with one or more of the deposition samples, and scanning the array utilizing a scanning probe microscope to characterize the molecular interaction events that have occurred between the target sample and the deposition material.
One object of this invention is the construction of relatively small molecular domains with large molecular species.
Another object of this invention is the construction of molecular arrays comprised of molecular domains, each containing as little as a solitary molecule.
Another object of the present invention is an apparatus and method for the creation of a molecular array comprised of one or more molecular domains, each with an area smaller than one micron.
Another object of this invention is the utilization of molecular domain arrays without having to perform a labeling step to allow for the detection of a molecular event.
Another object of this invention is a molecular deposition array that has an effective screening limit at the single molecule level.
Another object of the present invention is a method for using an AFM in a high throughput format to detect and evaluate interactions between molecules.
Another object of this invention is the placement of molecular deposition domains at a defined spatial address.
DETAILED DESCRIPTION
I. Definitions
The following are some definitions that may be helpful in understanding the description of the present invention. These are intended as general definitions and should in no way limit the scope of the present invention to those terms alone, but are put forth for a better understanding of the following description.
A. Deposition Material: This is a selected sample placed on a surface that can be recognized and/or reacted with by a target sample. The deposition material will ideally have a change inflicted upon it by one or more target samples that can be detected by later scanning with an SPM. This is the known material placed in the domain. Examples of deposition materials include, but are not limited to, biomolecules, proteins, a variety of chemicals, DNA, RNA, antibodies, or any other substance recognized by one skilled in the art which may have usefulness within the teaching of the present invention.
B. Deposition Domain: A deposition domain is a spot on a surface upon which a deposition material is placed. The domain may be of any size, shape, and pattern and may contain as little as one molecule of the deposition material. These deposition domains may alternatively be referred to as “spots” or “points.” The boundary of the domain is defined by the boundary of the material placed therein.
C. Array: Alternatively referred to using the term “array,” “bioarray,” “molecular array,” or “high density molecular array.” The term array will be used to describe the one or more molecular domains deposited on the surface.
D. Target Sample: A substance with a particular affinity for one or more deposition domains.
These target samples may be natural or man-made substances. The target samples may be known or unknowns present in a solution, gas, or other medium. These target samples may bind to the deposition domain or simply alter the deposition in some other cognizable way. Examples of target samples may include, but are not limited to, antibodies, drugs, nucleic acids, proteins, cellular extracts, antibodies, etc. The target medium may likewise be artificially made or, in the alternative, a biologically produced product.
E. AFM: As noted above, AFM's are a type of scanning probe microscope. The AFM is utilized in the present invention as an example of an SPM. The invention, however, is not limited for use with one specific type of AFM, but can also be incorporated for use with SPM's of various makes, models, and technological improvements.
F. Deposition Device: The deposition device of the following description is a modified AFM probe and tip. The basic probe and tip of the AFM is well known to one reasonably skilled in the art. The modified probe and tip that is the deposition device of the present invention may alternatively be referred to herein as “tip,” “probe tip,” or “deposition device.” Other deposition devices can be substituted by one reasonably skilled in the art, including the use of a dedicated deposition device manufactured for the express purpose of sample deposition.
II. General
The apparatus and method of the present invention allows for the placement of an at least one deposition sample in an at least one molecular deposition domain forming an array. The method of creating the present invention deposition domain may result in deposition domains smaller than one micron in total area. Furthermore, this method allows the deposition of relatively large molecular species, as large as 1 kilodalton and larger, without shearing or changing the molecular formation. This array can be exposed to a sample medium that may contain a target sample, the presence of which may be ascertained and characterized by detecting molecular interaction events. The molecular interaction event detection may be performed utilizing an atomic force microscope.
The deposition domains of the present invention may be formed as small or smaller than one micron in area. The present invention allows the direct detection of molecular interaction events in the deposition domain of the array. The molecular interaction event is detected without the need for the labeling of the deposition material or of the target sample. While labeling may still be performed for use with the present invention, the present invention does not require labeling to be utilized.
The present invention utilizes a scanning probe microscope to interrogate the various deposition domains of the present invention array. As the probe is scanned over a surface the interaction between the probe and the surface is detected, recorded, and displayed. If the probe is small and kept very close to the surface, the resolution of the SPM can be very high, even on the atomic scale in some cases.
In the present embodiment, an AFM may be used as the deposition tool, but this does not exclude other types of SPM's being used in alternative embodiments. An unmodified AFM probe has a sharp point with a radius of curvature that may be between 5 and 40 nm. The method herein uses a microfabricated deposition device with an apical radius on the order of 10-50 nm. Due to the small radius of curvature of the deposition device used herein, the spot size generated by the present method can range from larger spots to as small as 0.2 microns or smaller. The difficulties with the prior art method need for labeling, such as with radioactivity, fluorescence, enzymatic labeling, etc., are also avoided.
As one reasonably skilled in the art will appreciate, the molecular material deposited by the present invention may be of almost any size and type. The following materials and methods are not intended to exclude other materials that may be compatible with the present invention, however, the present example is given for better understanding of the scope of the present invention.
Surface Preparation
As shown in FIG. 1, block 1 , and FIG. 2, block 18 , a surface may first be provided. The deposition domains that form the array will be constructed on this surface. The surface used for the deposition of the present embodiment molecular domain should facilitate scanning by an AFM as well as facilitate the deposition of the deposition material. A surface which can accept and bind tenaciously to the deposition material may also be desired. The present embodiment utilizes a solid glass substrate. This solid glass substrate may be a glass slide well known to those reasonably skilled in the art. Other embodiments may use other substrates including, but not limited to, mica, silicon, and quartz. The present embodiment may further cover this surface with a freshly sputtered gold layer.
The ion beam sputtering of gold onto a surface is well known by those reasonably skilled in the art. Sputtering gold may produce an extremely smooth surface upon which a variety of chemistry and molecular binding may be performed. In other embodiments, the gold may be sputtered onto glass coverslips, smooth silicon, quartz or a similar flat surface. The smoothness required of the underlying substrate is a function of the sensitivity requirement of a particular test. For example, detection of a virus particle binding to antibodies on a surface requires only the smoothness of a typical glass coverslip. In contrast, detection of binding of a small ligand to a surface immobilized protein may require a supporting substrate with a surface roughness of one nanometer over an area of several microns.
In alternative embodiments, other surfaces besides that achieved by gold sputtering may be likewise utilized, such as, but not limited to, glass, Si, modified Si, (poly) tetrafluoroethylene, fnctionalized silanes, polystyrene, polycarbonate, polypropylene, or combinations thereof.
The gold of the present embodiment is sputtered onto the glass surface. This area of gold defines the boundary of the present embodiment array. The deposition material will be deposited in domains contained in this area.
Depositing the Deposition Sample on the Deposition Device
With reference to FIG. 1 block 12 , FIG. 2 block 20 , and FIG. 3, the deposition of the sample on the deposition device 40 will be described. The basic shape of the deposition device 40 is shown in FIG. 3 . Before the deposition material is formed into a molecular domain on the above surface, the deposition material must first be placed onto the deposition device 40 . The deposition device 40 of the present embodiment may be a deposition device 40 and tip 42 commonly utilized by an AFM. The present embodiment starts with a standard silicon-nitride AFM probe under the tradename “DNP Tip” produced by Digital Instruments, Inc. These probes are generally available and well known in the art. In the present embodiment, the deposition device 40 may be first placed on the deposition instrument. A Digital Instrument, Inc., Dimension 3100 may be used in the present embodiment, controlled by a standard computer and software package known in the art.
In the present embodiment, the deposition instrument may be modified with a microsphere 52 to facilitate the loading (depositing) of the deposition material 56 . While other embodiments may not utilize such a microsphere on the deposition device 40 , attaching a microsphere on the deposition device 40 allows the loading of a greater amount of deposition material upon the deposition device 40 , enabling a greater number of deposition domains 64 to be deposited before reloading with new material. Borosilicate glass spheres up to 25 microns or larger in diameter may be utilized in the present embodiment as the microspohere 52 .
First, a small amount of epoxy resin is placed upon a surface, usually glass. A standard ultraviolet activated epoxy resin, such as Norland Optical Adhesive #81, may be utilized, though those reasonably skilled in the art may fine other types of epoxies useful as well. The deposition device 40 is moved by the instrumentation and dipped slightly in the epoxy and withdrawn, retaining a small amount of the epoxy on the tip 42 . As shown in FIG. 4, on another surface 50 are placed a number of the microspheres 52 . Using the instrumentation controls, one or more of the borosilicate glass beads is touched by the end of the deposition device 40 . Because of the epoxy, the microsphere 52 sticks to the end of the deposition device 40 as it is pulled away. The deposition device 40 is then exposed to ultraviolet light to set the epoxy and permanently affix the microsphere glass bead 52 to the tip 42 of the deposition device 42 . As shown in FIG. 5 and 6, the microsphere 52 may bind to the tip 42 of the deposition device 40 in various places without affecting the present invention.
The present embodiment places one microsphere 52 on the deposition device 40 . This microsphere 52 allows the deposition device 40 to retain more of the material to be deposited on the probe while still allowing the creation of deposition domains 64 on the sub-micron scale. As noted above, as little as one microsphere 52 may be deposited on the tip in the above process. Furthermore, the surface of the microsphere 52 allows for alternative types of surface chemistry to be performed when, in alternative embodiments, the deposition material is being bonded to the surface.
The microspheres 52 used in the present embodiment are commercially available and well known in the art, ranging in size to smaller than 0.05 microns. With a smaller the microsphere 52 , a smaller deposition domain 64 may be achieved, however less sample can be deposited on the tip at any one time, slowing down the construction of the array. Modification of the deposition device 40 may also be accomplished in a number of alternative ways, including spontaneous adsorption of molecular species, chemical derivitization of the AFM tip followed by covalent coupling of the probe molecule to the tip, or the addition of microspheres to the tip which may be coupled to molecules by standard chemistry. In additional embodiments, a laser may be used to locally heat the deposition device 40 and bond microspheres (such as polystyrene spheres) by a “spot welding” technique.
As shown in FIG. 1 block 12 , and FIG. 2 block 20 , after the microsphere 52 is placed on the deposition device 40 , the deposition material 56 may be loaded on the deposition device 40 by forming a capillary bridge 60 . The deposition material 56 may be placed on a surface as shown in FIG. 7 a . This large spot of deposition material 56 can be reused a number of times, depending on the number of domains 64 that are to be created. Though not drawn to scale, FIG. 7 a shows material that may have been micro-pipetted onto a surface for loading on the deposition device 40 .
In one embodiment, the deposition device 40 may be brought into direct contact with the material 56 on the surface. In alternative embodiments, the deposition device 40 and microsphere 52 may be brought into a near proximity to the deposition material 56 on the surface and achieve the same capillary action. The exact distance between the microsphere 52 and the deposition material 56 may vary and still have the formation of a capillary bridge 60 . This depends on conditions like relative humidity, microsphere 52 size, contaminants, etc. In the present embodiment, this distance may vary between touching to several nanometers or more.
The capillary bridge 60 , shown in FIG. 7 b , may be formed by controlling the humidity by timing a blast of humid gas. Longer bursts may result in a greater amount of material to be placed on the tip. Short bursts allow for less material to be used, but must be long enough to effectively transfer deposition material 56 from the surface 62 to the deposition device 40 . The optimal parameters are determined empirically, however a typical time of exposure to the humid gas is on the order of 500 milliseconds or longer. It has also been noted that a capillary bridge 60 may be spontaneously generated when the relative humidity of the air is more than approximately 30%. In cases such as this, it may be advantageous to have a controlled dry environment or to have a stream of dry air flowing over the surface which is interrupted by the humid blast of gas which forms the capillary bridge 60 . In other embodiments, this spontaneous capillary bridge 60 can be used to deposit the deposition material 56 , though less control of the process may result.
In the present invention the humidity may be controlled by several methods known to those reasonably skilled in the art. The present embodiment incorporates a small tube and argon gas source which creates the bridge by rapidly increasing the level of humidity around the probe and the deposition material. The tube of the present embodiment may be a flexible polymer material, such at “Tygon” tubing, with an inner diameter of 0.5 to 1.0 cm. This material is readily available, but other materials that will not introduce contaminants into the deposition material would likewise suffice. The small tube must first be filled with water.
The water used in the present embodiment should be of a highly purified nature, such as purified water with a resistance of 18 megaohms or more. It should be free of particulates by filtration and is usually sterilized by filtration and or autoclaving. Additionally, an argon gas source may be positioned at one end of the tube and may be controlled by the action of a needle valve and solenoid.
The water is then drained from the tube, leaving a humid gas in the tube. When the humidity blast is desired, the solenoid is activated to pulse a discrete amount of humidified argon through the tube and over the probe 40 , deposition material 56 , and surface 62 . As shown in FIG. 7 b , the capillary bridge 60 may be formed between the surface 62 and the deposition device 40 . The deposition device 40 is then moved away from the surface 62 , leaving a small amount of the deposition material 56 on the deposition device 40 , as shown in FIG. 8 a.
As shown in FIG. 8 a , the deposition material 56 is now on the deposition device 40 . Whether the deposition material 56 adsorbs onto the microsphere's 52 surface, the pores, or some other area, may vary depending on the type of microsphere 52 and the deposition material 54 . As shown in FIG. 1 block 14 , the deposition material 56 may now be dried on the deposition device 40 . The drying may be immediate and spontaneous due to the relatively little amount of wet material on the surface of the deposition device 40 . This is, of course, dependent on the relative humidity of the surrounding air. Drying the deposition material 56 on the microsphere 56 may facilitate the deposition of the material 56 on the surface 62 as laid out in the next step. For labile samples, drying could result in inactivation, and should be avoided, but this is not the case for robust samples such as antibodies, peptides and nucleic acids.
In an alternative embodiment, the deposition tip may be loaded with the deposition material 56 by direct immersion. The tip of the probe may be immersed in a solution containing up to 50% glycerol, 0.1-5 mg/ml of the deposition sample, and a buffer-electrolyte such as Tris-HCl at pH 7.5. A small amount of the above solution may be made by standard bench chemistry techniques known to those skilled in the art. Typically 1-10 microliters are made. Because of the nature of solutions, when the probe is dipped into the solution and withdrawn a small amount of the solution will cling to the surface of the tip in a manner known to those reasonably skilled in the art. In still further embodiments, other solutions, such as 10 mM NaCl and 1 mM MgCl 2 , phosphate buffered saline, or a sodium chloride solution, may be substituted by those reasonably skilled in the art. Alternative methods for loading the deposition material 56 on the deposition device 40 include spraying, chemically mediated adsorption and delivery, electronically mediated adsorption and delivery, and either passive or active capillary filling.
In still further embodiments, other probes may also be used, for example, AFM probes lacking a tip altogether (tipless levers), may also be used. The type of probe used may impact the spatial dimensions of the deposition domain 64 and may be influenced by the choice of the deposition sample.
Depositing the Sample on the Surface
The next step in creating the deposition domain 64 and array 66 is depositing the sample on the surface. See FIG. 1 block 16 and FIG. 2 block 22 . Varying the humidity level surrounding the deposition device 40 and deposition material 56 may be taken advantage of to deposit the deposition material 56 onto the surface in a deposition domain 64 less than one micron in area. The capillary bridge 60 is illustrated by FIG. 8 b . This step may be performed in much the same way as depositing the deposition material 56 on the deposition device 40 . The degree of binding to the surface and the deposition device 40 is a function of the hydrophilicity and hydrophobicity of the two surfaces. Therefore, it may often be desirable to use deposition tools and surfaces that are free of oils and other hydrophobic contaminants to facilitate wetting of both surfaces.
Utilizing the AFM and the control computer and software, the deposition device 40 , with the deposition material 56 , may be brought into contact, or close proximity, with the deposition surface. The humid gas may then be released by activation of the solenoid. In the present embodiment the humidity is ramped up, and the capillary bridge 60 formed, for a time of approximately 400 milliseconds or less, depending on the amount of material the user wishes to deposit. The spots are on the sub-micron scale because the contact surfaces are on the order of microns or smaller and the degree of sample diffusion (which determines the final size of the deposition domain) is carefully controlled by regulating the amount and timing of the humid gas burst. When depositing the deposition sample 56 on the surface, in order to better control the length of time the capillary bridge 60 exists, a tube of dry air may be blown over the area by a solenoid in rapid succession after the humid air. This results in a very short burst of humid air, a capillary bridge 60 , and then the termination of the capillary bridge 60 , all in a very short time period. As illustrated in FIG. 9, when the deposition device 40 is withdrawn, and the bridge 60 severed, a very small amount of the deposition material 56 has been deposited on the surface 62 in a deposition domain 64 . The transfer of large macromolecules may be achieved utilizing the burst of humid gas. As will be appreciated by one reasonably skilled in the art, the capillary bridge 60 may be broken by withdrawing the deposition device 40 or by the blast of dry air.
Because of the fine control of the deposition device 40 that may be possible with the AFM instrumentation, the exact surface spot in which the deposition takes place may be noted. Noting the surface point for each deposition domain 64 may ameliorate the detection of the molecular interaction event caused by the target sample. The pattern writing program can be one that is provided by an AFM manufacturer (e.g., the Nanolithography program provided by Digital Instruments, Inc.) or it can be created in-house. In the latter case, one example is to use a programming environment such as Lab View (National Instruments) with associated hardware to generate signal pulses which control the positioning of the deposition probe.
The steps laid out above produce the deposition domain 64 of the present embodiment. Repeating these steps with one or more deposition materials 56 , FIG. 2 block 26 , produces the array 66 of the present invention. This array is shown in FIG. 10 . The number and size of the deposition domains 64 may be varied depending on the desire of the user.
One advantage to the present embodiment is the small size of the deposition domain 64 produced by the method. Furthermore, because of the manner in which the array 66 is produced, the user may be able to record and track the position of each of the particular deposition domains 64 . Finally, the above method allows the deposition of as little as a single macromolecule, which previous methods were unable to perform.
Once the array 66 has been formed, the user may desire to immediately utilize the array 66 on site, or may desire shipment of the array 66 for exposure to a sample medium at another location. The array 66 produced by the above steps may be ideal for shipment to a location, exposure, and return shipment for the scanning by an AFM.
Subsequent Depositions
In an alternative embodiment, the probe may be reloaded with a second deposition material 56 after one or more molecular domains are created with the first deposition material 56 . FIG. 2 block 26 . Using the probe with a variety of deposition materials 56 enables the creation of a number of deposition domains 64 on one surface. The different deposition materials 56 in the molecular domains that are deposited on the surface form the array 66 of the present invention. Because of the size of the molecular domain containing the deposition material 56 , the molecular domains can be placed on the surface in a an ultra high density array 66 , as shown in FIG. 10 . In the present embodiment of this invention, the pitch (the distance from the center of one domain to the center of the next domain) of the molecular domains may be as small or smaller than one micron. The array 66 produced with these small molecular domains may be easily scanned by the AFM array 66 after the array 66 is exposed to the sample medium containing the target sample in the next step. Furthermore, the small sized array 66 requires exposure to a smaller amount of the sample medium of the next step, conserving both the deposition material 56 and the medium material.
The number of times the probe may be reloaded in this alternative embodiment may be only limited by the surface size and the number of samples the user desires to deposit. As will be appreciated by those skilled in the art, this ultra high density array 66 presents a unique advantage.
Cleaning the Probe
Before the probe is reloaded with subsequent deposition samples, the probe must be cleaned. FIG. 2 block 24 . The probe of the present embodiment AFM may be cleaned in several ways. In the present embodiment, the very tip of the probe is immersed in a small aliquot of a cleaning solution. The present embodiment cleaning step utilizes pure water as the solution. A few microliters of water is pipetted onto a surface and, using the instrumentation's piezo device (which is utilized to help the AFM scan surfaces), the tip is oscillated at up to 1000 Hz or more. Resonating the probe at 1000 hertz will effectively sonicate the tip, helping to effectuate reusing the tip to deposit other deposition materials 56 .
Exposing the Array to a Sample Medium
Once a high density array 66 is formed by the present invention, the array 66 may be exposed to a sample medium. FIG. 2 block 28 . The sample medium may contain a target sample that the user has placed therein. In other types of experiments, the user may be looking for the presence of an unknown target sample, utilizing the array 66 of the present invention to test for its presence. The usefulness of such arrays 66 are well known to those reasonably skilled in the art.
The array 66 may be dipped in a solution or exposed to a gas. The solution may include, but is not limited to, waste water, biological materials, organic or inorganic user prepared solutions, etc. The exposure time of the array 66 to the medium depends on what types of molecular interaction events the user may be studying. The target sample tested for should ideally cause a readable molecular change in one or more of the deposition materials 56 of the molecular domains placed on the array 66 . These molecular changes may include binding, changes in stereochemical orientation in morphology, dimensional changes in all directions, changes in elasticity, compressibility, or frictional coefficient, etc. The above changes are what the AFM scans and reads in the next step of the present embodiment.
Molecular Event Detection
After the molecular deposition array 66 is exposed to the test medium, it may be scanned by the AFM. See FIG. 2 block 30 . Use of an AFM in this manner to characterize a material deposited on a surface is well known to those reasonably skilled in the art. The present embodiment may utilize one scan for every deposition domain 64 of the array 66 to look for changes in the recorded features of the domains. Furthermore, the AFM may look at specific portions of the array 66 using site locators. As will be appreciated by one skilled in the art, various methods may be used to undertake the scanning of the array 66 of the present invention.
After the scan is taken, the scan must be analyzed. FIG. 2, block 32 . The present embodiment utilizes the detection of changes in height at defined spatial addresses, as described by Jones et al., supra. As shown in FIG. 11, height changes only occur at those addresses containing deposition material 56 to which the target sample is capable of binding. Since the identity of the molecules at each of the sample addresses is known, this process immediately identifies those deposition materials 56 capable of binding to the target sample. In FIG. 11, point 66 shows the normal height of the deposition domain 64 as scanned by the AFM. Point 68 shows how the AFM will recognize some feature that the molecular interaction event has affected in the deposition domain 64 .
In addition, the AFM can measure whether new materials have bonded to the deposition material 56 by testing for changes in shape (morphology) as well as changes in local mechanical properties (friction, elasticity, compressibility, etc.) by virtue of changes in the interaction between the probe and the surface. The typical parameters detected by an AFM include height, torsion, frequency (the oscillation frequency of the AFM probe in AC modes of operation), phase (the phase shift between the driving signal and the cantilever oscillation in AC modes) and amplitude (the amplitude of the oscillating cantilever in AC modes of operation).
The AFM scan may also be used to tell when the probe is interacting with different forces of adhesion (friction) at different domains on the surface. This interaction force is a consequence of the interaction between the molecules on the probe and on the surface. When there is a specific interaction, the force value is typically higher than for non-specific interactions, although this may not be universally true (since some non-specific interactions can be very strong). Therefore, it may be useful to include both known positive and negative control domains in the scan area to help distinguish between specific and non-specific force interactions. The target sample may affect the deposition material 56 that can be read by this scanning technique. A still further embodiment may directly measure the interaction forces between a molecular probe coupled to the AFM tip and the surface. The direct measurement of molecular unbonding forces has been well described in the art in addition to measuring changes in the elasticity.
In the screening methods described above, once it has been established that a molecular binding event has occurred, changes in the degree of binding upon introduction of additional sample molecules may also be analyzed. The potential for a third molecular species to enhance or inhibit a defined molecular interaction is of utility in locating new drugs and other important effectors of defined molecular interactions.
In the above examples an AFM is used for illustration purposes. The type of deposition instrumentation incorporated into the present invention is not limited to AFM's, or other types of SPM's. In one alternative embodiment, a dedicated deposition instrument may be used which may provide for extremely accurate control of the deposition probe. In this alternative embodiment, a DC stepper motor and a piezoelectric motion control device may be incorporated for sample and probe control. In still further embodiments, a force feedback system may be included to minimize the force exerted between the deposition tool and the surface.
One advantage to the present invention is the elimination of the labeling step required in other array 66 techniques. Radioactive and fluorescent labeling may be cost prohibitive and complex. The present invention eliminates the need for the labeling of molecular deposition domains 64 in an array 66 .
Another advantage to the present invention is the creation of molecular domains in an array 66 wherein each domain has a deposition area of less than one micron. Since the size of each domain is extremely small, a large number of domains may be placed in a small area, requiring less materials, a smaller medium sample for exposure, and the ability to perform a quicker scan.
Another advantage to the present invention array 66 is the ability to quickly scan for multiple molecular events in a reasonably short period of time.
III. ALTERNATIVE DEPOSITION EXAMPLES
The following are a few of the variations in the deposition method and array 66 apparatus that may be used within the scope of the present invention. These examples are given to show the scope and versatility of the present invention and are not intended to limit the invention to only those examples given herein. In each of these examples, the deposition material 56 may be deposited on the deposition device 40 and then to the surface utilizing the method described above, however the surface may be coated with other materials that will react in some way with the deposition material 56 , to bind the latter to the surface in the deposition domain 64 .
A. Surface Modification
One alternative embodiment for the covalent tethering of biomaterials to a surface for use in the present invention may be to use a chemically reactive surface. Such surfaces include, but are not limited to, surfaces with terminal succinimide groups, aldehyde groups, carboxyl groups, vinyl groups, and photoactivatable aryl azide groups. Other surfaces are known to those reasonably skilled in the art. Biomaterials may include primary amines and a catalyst such as the carbodiimide EDAC (1-ethyl-3-[3-dimethylaminopropyl]carbodiimide). Furthermore, the spontaneous coupling of succinimide, or in the alternative, aldehyde surface groups, to primary amines at a physiological pH may be incorporated for attaching molecules to the surface. In still another embodiment, photoactivatable surfaces, such as those containing aryl azides, may be utilized. These photoactivatable surfaces form highly reactive nitrenes that react promiscuously with a variety of chemical groups upon ultraviolet activation. Placing the deposition sample on the surface and then activating the material can create deposition domains 64 in spots or patterns, limited only by the light source activated.
Another embodiment for the tenacious and controlled binding of biomaterials to surfaces is to exploit the strong interactions between various biochemical moieties. For example, histidine binds tightly to nickel. Therefore, both nucleic acid and protein biomaterials may be modified using recombinant methods to produce runs of histidine, usually 6 to 10 amino acids long. This His-rich domain then allows these molecules to bind tightly to nickel coated surfaces. Alternatively, sulfhydryl groups can be introduced into protein and nucleic acid biomaterials, or preexist there, and can be used to bind the biomaterials to gold surfaces by virtue of extremely strong gold-sulfur interaction. It is well documented that gold binds to sulfur with a binding force comparable to that of a covalent bond. Therefore, gold-sulfur interactions have been widely exploited to tether molecules to surfaces. Jones, V. W., J. R. Kenseth, M. D. Porter, C. L. Mosher, and E. Henderson, Microminiaturized Immunoassays Using Atomic Force Microscopy and Compositionally Patterned Antigen Arrays 66 , Anal Chem. 1998, p. 1233-41.
B. Aptes
In this alternative embodiment, the surface may be treated with APTES (aminopropyl triethoxy silane). The APTES placed on the surface may present positively charged amino groups that can bind tightly to a negative charge. Materials such as DNA and RNA containing negatively charged groups may therefore bond to the surface after the APTES treatment. The details of the adsorption mechanism involved in this spontaneous attachment are not well defined. Therefore, in alternative embodiments, it may be advantageous to deposit biomaterials onto surfaces that can be covalently or otherwise tenaciously coupled to the target sample. DNA and RNA bind through interaction between their negative net charge and the net positive charge of the APTES surface.
C. Photochemical Sample Deposition
In this alternative embodiment, glass surfaces may be modified sequentially by two compounds, aminopropyltriethoxysilane (APTES) and N-5-azido-2-nitrobenzoyloxysuccinimide (ANB-NOS). The glass may first be treated with APTES to generate a surface with protruding amino groups (NH 2 ). These groups may be then reacted with the succinimide moiety of ANB-NOS in the dark. These steps produce a surface with protruding nitrobenzene groups. The photosensitive surface may be then reacted with the first deposition material 56 in the dark, then a focused light source, like a laser, may be used to illuminate a portion of the surface. These acts result in localized covalent binding of the first deposition material 56 to the surface. The deposition material 56 not bonded to the surface may then be washed away and second deposition material 56 added by repeating the process. Reiteration of this process results in the creation of a biomolecular array 66 with address dimensions in the 1 micron size range. A limitation of this deposition method is that the sample size is dependent on the size of the illuminating light field.
A variation of the above embodiment may be to utilize the deposition device 40 and humidity ramping deposition technique described to place various molecular species at defined locations in the dark. After construction of the desired array 66 , the entire surface is exposed to light, thereby cross linking the molecular species at discrete spatial domains. This process may overcome the spatial limitation imposed by use of a far field laser or other type of light beam.
D. Photocoupling
In this embodiment a near field scanning optical microscope (NSOM) may be used to supply the light energy necessary to accomplish photocoupling of the sample molecule to a surface at a defined spatial address. The NSOM may overcome the diffraction limit which constrains the address size created by far field photocoupling as described in Example 2. The photoactive surface is prepared as described in Example II. The first molecule to be coupled is added to the surface and subjected to a nearfield evanescent wave emanating from the aperture of the NSOM. The evanescent wave energy may then activate the photosensitive surface and result in coupling of the sample molecules to a spatial address in the 10 to 100 nm size range. The first sample molecule is washed away and the process repeated with a second sample molecule. Reiteration of this process may result in the production of an array 66 of sample molecules coupled at spatial addresses with submicron dimensions.
An alternative approach may be to utilize both the sample manipulation and near field light delivery capabilities of the NSOM. In this approach, the NSOM probe may be first loaded with a molecular species as described in Example I. Then the same probe is used to provide the light energy to couple the molecule to the surface. The probe may then be washed and reused to create a spatial array 66 of molecular species covalently coupled to defined domains.
One advantage of coupling the deposition material 56 to the surface may be that the molecule may remain attached at a defined spatial domain even under stringent wash and manipulation conditions. Moreover, by coupling the molecule, the orientation of the molecules on the surface may be controlled by the careful selection of a tethering method.
Yet another advantage to coupling the molecule is that by controlling the coupling chemistry, the minimization of the chances of surface induced molecular denaturation may be achieved. Coupling the molecules to the surface may be especially advantageous when depositing biomolecules.
The information and examples described herein are for illustrative purposes and are not meant to exclude any derivations or alternative methods that are within the conceptual context of the invention. It is contemplated that various deviations can be made to this embodiment without deviating from the scope of the present invention. Accordingly, it is intended that the scope of the present invention be dictated by the appended claims rather than by the foregoing description of this embodiment.
All publications cited in this application are incorporated by reference in their entirety for all purposes. | The invention is a method for the formation and analysis of novel miniature deposition domains. These deposition domains are placed on a surface to form a molecular array. The molecular array is scanned with an AFM to analyze molecular recognition events and the effect of introduced agents on defined molecular interactions. This approach can be carried out in a high throughput format, allowing rapid screening of thousands of molecular species in a solid state array. The procedures described here have the added benefit of allowing the measurement of changes in molecular binding events resulting from changes in the analysis environment or introduction of additional effector molecules to the assay system. The processes described herein are extremely useful in the search for compounds such as new drugs for treatment of undesirable physiological conditions. The method and apparatus of the present invention does not require the labeling of the deposition material or the target sample and may also be used to deposit large size molecules without harming the same. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to methods for decomposing organic materials into hydrogen gas and elemental carbon in the form of carbon black, and to a smaller extent carbon monoxide. More particularly, the present invention is directed to an improved method of processing and converting organic materials, including organic waste materials such as non-pretreated infectious hospital wastes, refinery wastes, paper wastes, food processing wastes, and other similar solid and liquid organic wastes, into carbon, preferably in the form of carbon black, by exposing the organic material to a sufficiently intense field of radiant energy that primarily promotes the chemical reactions resulting in the decomposition of the organic materials into hydrogen and carbon and small amounts of carbon monoxide.
Carbon black is a low density, porous form of carbon. It is used in the fabrication and manufacture of many items including automobile tires and audio and video tapes. Typically, the "bottoms" or waste oil from refineries have been used in the manufacture of carbon black. The conventional manufacturing process requires the use of special reactors, high temperatures and the combustion of fossil fuels. The cost of this manufacturing carbon black has been on the order of twenty cents per pound.
The management of wastes produced by industry, hospitals and homes is an ever growing concern and becoming a crisis. Landfilling, the traditional waste treatment method in the United States, is now considered the method of last choice. Existing landfills are rapidly filling, are leaking and polluting the ground water and are being added to the Super Fund list. As a matter of political reality, it is becoming increasingly difficult to establish new landfills.
Incineration is becoming the waste treatment method of choice for industry. Citizen resistance to incineration, however, is strong and increasing because of the small amounts of toxic, organic chemicals, dioxins and furans, emitted by incinerators and because of the difficulties associated with the operation of incinerators. In addition, incinerators are expensive and their use has always resulted in a large increase in the cost of waste management. As a practical matter, obtaining the required governmental permits for new incinerators is becoming as difficult as obtaining the permits for new landfills.
As the environmental requirements for landfills are increased and the use of incineration increases, the costs for management of wastes is increasing rapidly. Solid waste disposal costs for 1989 increased by a factor of three, compared to 1988, in Pittsburgh and are generally between $50 and $125 per ton in New Jersey and other Northeastern States.
Infectious wastes, as for example those produced by hospitals, are currently receiving much attention because these wastes have been washing ashore on the beaches of New York and New Jersey for the past two summers. Hospitals are paying high prices, $800 or more per ton, to dispose of such wastes. Citizen opposition has stymied, as a practical matter, many hospitals in attempting to install their own incinerator. The Federal Government and many states are beginning to develop regulations over incinerators. A few States regulate infectious wastes as hazardous wastes. This regulation will further increase the costs of disposing of infectious wastes.
In the incineration process, the oxidation of the fossil fuels creates high temperatures and thus high kinetic energies. As a result of inelastic collisions among the molecules, kinetic energy is transformed into the internal energy of the molecules, usually vibrational energy, which causes chemical reactions between the organic material and oxygen to occur.
The Hobbs U.S. Pat. No. 3,648,630 Hobbs and the Hardison U.S. Pat. No. 4,667,609 describe incinerators that used infrared radiation from blackbody radiators to heat solids to promote combustion. These incinerators are similar to fossil fired incinerators in other respects. The Galloway U.S. Pat. No. 4,688,495 employs resistance heaters to heat gases to promote incineration.
The Matovich U.S. Pat. No. 3,933,434 describes the High Temperature Fluid Reactor, a chemical reactor in which the energy required is supplied by radiation. This patented reactor consists of large concentric vertical, annular radiation zones. Inert nitrogen gas flows into and through the radiation zones during operation. Reactant materials are introduced into the top of the reactor and fall vertically through the radiation in the radiation zone to promote the chemical decomposition reactions. Preprocessing of materials into extremely small, fine particles is, however, necessary to control the transit time of the reactant materials through the radiation zone. Subsequent U.S. Pat. Nos. 4,042,334; 4,044,117; 4,056,602; and 4,059,416 disclose refinements without altering the basic fluid wall.
The patented Matovich type reactor promotes decomposition of organic materials into carbon black and hydrogen by "pumping" energy into solid particles using light. The reactor creates the light flux by employing imperfect blackbody radiators, i.e. devices heated to a sufficiently high temperature that they radiate large amounts of radiation. Oxygen is excluded from the Matovich type reactor by the use of a flowing stream of inert nitrogen gas, the fluid wall, throughout the reactor. The reactant materials are at a higher energy level than the nitrogen gases because these materials are far better absorbers of radiation than the nitrogen gas.
Similarly the Westinghouse Electric Corporation has described an electric pyrolyzer system that may be used, at 3000° F. and in a low oxygen or oxygen-free environment, to destroy organic solids, and sludges, and to melt inorganic solids to form a glass-like residue. This system employs a molten glass bath to entrap and remove the residue. See in this regard, the report in the May/June 1988 edition of THE HAZARDOUS WASTE CONSULTANT, especially pages 4-12 through 4-14.
SUMMARY OF THE INVENTION
In its principal aspects, the present invention provides an improved method for converting organic material, and particularly organic materials such as non-pretreated infectious hospital waste, refinery waste, paper waste, food processing waste, and other similar solid or liquid organic wastes into hydrogen and elemental carbon, preferably in the form of carbon black, and carbon monoxide. This improved method employs a substantially closed reactor having an internal reaction chamber or cavity made of materials that can tolerate the presence of oxygen at high temperatures, that possess low thermal mass, that limit or restrict the passage of heat and that may function as almost perfect black bodies at high temperatures. The improved method produces useable carbon black, and thus has the double benefit of eliminating organic waste materials while producing a useful end product in an efficient, economical manner. Organic materials, in the present method, are induced to decompose primarily and solely through their exposure to a sufficiently intense field of radiant energy. As a result of exposure to the radiation field, the energy level of the individual organic molecules is elevated to a sufficiently high level that the large organic molecules are no longer stable and decompose into their constituent atoms and smaller molecules, such as carbon monoxide and hydrogen.
In the improved method of the present invention and in contrast with incineration processes, the organic materials do not react directly with oxygen. The oxygen content in the substantially closed reactor is kept to a minimum by deliberately limiting the amount of air introduced into the reaction chamber with reactant organic materials.
The improved method similarly does not require the use of an inert gas, i.e. nitrogen gas or fluid wall, that is required to be employed in the patented Matovich reactor to protect it from being destroyed as a result of oxidation. In addition and unlike the reactant materials in the Matovich reactor, the reactant materials do not have to be finely ground because they are contained in a reaction chamber and do not have to be passed between and through concentric annular radiation zones. This affords the present invention a significant economic advantage over the Matovich reactor.
Furthermore, reactors for use in connection with the present method can be heated relatively rapidly, in one to two hours, as compared with the Westinghouse system reactor. All the energy needed is furnished by radiant heaters, unlike the Westinghouse system where more than one-half the energy is supplied by the glass bath. These features make the present invention commercially attractive especially to smaller users, such as hospitals and the like, who can practice the improved method at their own facilities.
Lastly, the present method converts all the carbon in the organic materials to carbon black that may then be collected or that may alternatively be further converted through oxidation reactions. Having these options is unique with the present invention.
Accordingly, it is an object of the present invention to provide an improved method of processing and converting organic materials, including organic waste materials such as non-pretreated hospital infectious waste, refinery waste, paper waste, food processing waste, and other similar solid and liquid organic wastes, into predominantly hydrogen and carbon black, with some relatively small amounts of carbon monoxide. A related object of the present invention is to provide an improved method, as described, wherein the organic waste materials decompose solely as a result of their exposure to radiant energy.
Another object of the present invention is to provide an improved method as described which includes the steps of: introducing the organic waste materials into the interior of a substantially closed reactor; exposing the waste materials in the interior of the reactor to a sufficiently intense field of radiant energy for sufficient times such that the organic molecules in the waste materials decompose, primarily and solely as a result of their exposure to the radiant energy, into their elemental atomic particles and smaller molecules including hydrogen, carbon in the form of diffused carbon black powder, and carbon monoxide; and withdrawing the diffused carbon black powder and gases from the interior of the reactor. A further related object of the present invention is to provide an improved method, as described, wherein the waste materials do not have to be pretreated except that they may be shredded into particles of the size sufficient to allow them to be facilely introduced into the reactor. A still further related object of the present invention is to provide an improved method, as described, wherein the interior of the reactor is lined with fibrous ceramic materials that will enable the reactor to be efficiently and readily heated so that reactors of the type required to perform the improved method of the present invention may be installed in and operated efficiently by hospitals.
These and other objects, advantages and benefits of the present invention will become apparent from the following description of the preferred embodiment of the invention, described in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic layout view of a reactor system that may be used to produce carbon black from solid or liquid organic materials in accordance with the teaching of the present invention;
FIG. 2 is a partial schematic layout view of a reactor system that may be used to produce carbon dioxide; and
FIG. 3 is a partial, vertical cross-sectional view showing the interior components and arrangement of the reactor used in the reactor system of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 and 3, a reactor, shown generally at 10, includes a top wall 12, a bottom wall 14 and side walls 16. The walls 12-16 serve to define a substantially closed, internal reaction chamber or cavity 18 within the reactor 10. Both the reactor 10 and its internal chamber 18 are shown, in FIG. 3, as being generally cubic in overall configuration, but their particular configuration or shape is not critical to their performance of the improved method of the present invention.
The walls 12-16 of the reactor 10 are constructed out of fibrous ceramics material. Steel or other such materials, not shown in FIG. 3, are used as an outer reinforcement and for structural strength for the fibrous ceramic materials. The thickness of the walls is chosen to minimize energy loss. The particular materials used to construct the walls and the thickness of the wall are determined by the particular operating temperatures selected for the reactor. For example, if the maximum operating temperature in the chamber is to be 1500° C., the materials forming the chamber 18 should be suitable for temperatures up to 1650° C. or more. With these temperatures, the walls 12-16 preferably should be at least six or more inches thick so that the outer shell temperature of the reactor 10 will be sufficiently low so as not to be a hazard and to reduce energy losses from the reactor. Fibrous ceramics materials that may be used for this purpose include those marketed by Industrial Insulation Inc. of City of Industry, Calif. under the designation MaxFire Board.
The reactor 10 may be used to process a variety of different types of organic materials. These materials can include waste materials such as infectious hospital wastes, refinery wastes, paper wastes, food processing wastes and other similar solid or liquid organic wastes. Preferably the waste materials should contain 95% or greater organic matter, but the improved method will satisfactorily decompose materials containing larger amounts, for example, on the order of 20%, of inorganic matter. The solid waste materials may be in a variety of assorted sizes and shapes. The materials need not be pre-treated, that is, they can be processed as they are received from their sources except as explained below, the materials may have to be roughly shredded or broken down to a size and shape that can be readily introduced into the reactor.
When these materials are in solid form, a vertically oriented feed chute 22 may be used to introduce or feed them into the reaction chamber 18. The chute 22 is generally cylindrical in shape. Its lower end opens directly into the chamber 18, and its upper end is normally closed by a removable cover plate 24. To conserve energy and to trap radiant energy within the reactor, the length of the chute 22 is more than four times its diameter. The walls of the chute are constructed of fibrous ceramic material such as those marketed by Industry Insulation Inc. of City of Industry, Calif. under the designation MaxFire.
A conventional, steel knife valve 26 is mounted within the chute 22 and is used to control the feeding of waste materials into the chamber 18. An example of such a valve is the Meyer Slide Gate marketed by William W. Meyer & Sons, Inc. of Skokie, Ill. If the continuous feeding of waste materials is desired, a rotary valve 25 may be used. An example of such a rotary valve is the "Meyer's Rolo-Flo" valve marketed by William W. Meyer & Sons, Inc. of Skokie, Ill. Whatever type of valve or assembly is utilized, the introduction of oxygen into the chamber 18 through the feed chute should be restricted so as to minimize, to the extent practicable, having unwanted oxidation occurring in the chamber 18.
The solid materials to be processed are stored in a conventional storage bin 28 and may be loaded into the chute 22, without any pre-treatment, by means of a conventional conveyor 32, such as a screw feeder. After the chute 22 is loaded, the cover 24 is again placed over the upper end of the chute and the valve 26 is opened. If all or part of the waste materials are too bulky to fit easily within the chute 22, they may be roughly reduced in size by a conventional shredder shown generally at 34.
A plurality of conventional radiant heaters 36, such as electrical resistance heaters, two of which are shown in FIGS. 1 and 3, are mounted in the top wall 12 of the reactor 10 and hang from that wall into the chamber 18. The size and number of the heaters 36 is determined by the size and the desired processing rate of the reactor 10. The particular orientation of the heaters is inconsequential. In this regard, the heaters 36 must, however, supply a sufficiently intense field of radiant energy needed to maintain the reactor 10 at operating temperature and to drive the desired chemical reactions.
The size of the reactor 10, its wall thickness, the size of the chamber 18, and the particular fibrous ceramic materials used will be determinative of the energy needed to maintain the reactor at any given temperature. Ultimately the choice of heaters 36 is based on economic considerations and the operating temperatures required for the particular material or materials being processed. Specifically, however, the heaters 36 need to have the capacity to be able to heat the chamber 18 to temperatures between around 1100° C. and around 1500° C. and preferably around 1260° C. Heaters having this capacity include the model "Kanthal Super ST" marketed by The Kanthal Corp. of Bethel Connecticut.
With respect to decomposing organic materials, it is known that under appropriate conditions organic molecules will decompose into their constituent atoms. Decomposition of organic molecules occurs in the absence of reactive species, including oxygen, and when the energy of the molecules is sufficiently high that the molecules are not stable. In high energy states, the molecular form becomes less stable than the state in which the individual atoms are not associated with other atoms.
In large, complicated organic molecules, all of the various forms of internal energy are coupled to each other. Thus, rotational energy, vibrational energy, and electronic energy are coupled and interchanges occur. Kinetic energy is coupled to the internal energies via inelastic collisions among the molecules. The interchange of kinetic energy with internal energies occurs more slowly and less efficiently than interchange of energy among the various kinds of internal energy.
A common method of achieving high energy levels is to raise the kinetic energy of the molecules. Temperature is a direct measure of the kinetic energy. The combustion of fossil fuels or organic materials is commonly used to produce the kinetic energy required to achieve high temperatures. Energy transfer in such reactors is predominantly via convection, the movement of gases, and collisions among particles. Energy is exchanged among the various gases components as a result of collisions. All of the materials within such a reactor are heated to the same temperature in this manner.
Electrically powered resistance heaters, such as the heaters 36, produce heat by the interaction of the electrical current with the materials. The amount of current flow and the properties of the material, in particular the electrical resistance, determine the energy produced. At relatively low temperatures, below 1000° C., the energy is removed from these heaters through the interaction with gases. At higher temperatures, the heaters radiate energy as light and approach the behavior of black body radiators.
The theory of black body radiators is known. The energy radiated is governed by the Stefan-Boltzmann equation
M=cT.sup.4
where c is Stephan's constant, M is the power radiated, and T is the absolute temperature. The spectral distribution of the radiation is given by Planck's law
m=C/ (L.sup.5 (exp(K/LT)-1))
where C and K are constants, L is the wavelength of the radiation, T is the absolute temperature, and m is the power radiated per unit area at the wavelength L. The maximum monochromatic emissivity is given by Wien's law
L*T=W
where L is the wavelength at which the maximum energy is radiated, T is the absolute temperature, and W is a constant.
As is apparent from the Stefan-Boltzmann equation, the radiated energy is proportional to the fourth power of the absolute temperature and thus increases rapidly with temperature. At temperatures about 1100° C., radiant energy transfer is larger than energy transfer by natural convection. Radiant energy transfer is very fast since the energy is carried by light and occurs between any two objects visible to each other.
At the temperatures discussed above, that is, temperatures in the range of around 1100° C. to around 1500° C., the walls of the reaction chamber 18 may radiate light with an efficiency of about ninety-three percent. Thus, at these temperatures an intense radiation field permeates the chamber even when the heaters 36 are not operating. This radiation field is primarily infra-red light and preferably, should have a density of forty or more watts per cubic centimeter.
As organic materials are fed into the chamber 18, they are immediately within this intense radiation field. The characteristics of the radiation field are determined by the Stefan-Boltzmann, Planck and Wien equations. Infra-red radiation does not interact strongly with gases but does interact with solid materials. Its energy is absorbed by the solids and is transferred to internal energies. When sufficient energy is absorbed by the individual organic molecules, unimolecular decomposition of the organic molecules into atoms occurs.
Organic molecules decompose into carbon, hydrogen, and small amounts of other elements. The carbon typically forms as a porous solid powder although some of the carbon will subsequentally react to form carbon monoxide because as a practical matter, a limited amount of oxygen is introduced into the chamber with the organic materials. The introduction of this oxygen is not desired and as noted above, should be limited as much as practicable. The reason for this is that pursuant to the method of this invention, the decomposition of the waste materials should, to the extent practicable, be due to the radiant energy; not as a result of oxidation reactions.
Electrical current is supplied to the heaters 36 via a conventional power controller 38 and a transformer 42. The amount of current is controlled so as to maintain a preselected temperature in the chamber 18. Temperature may be measured within the chamber 18 by a conventional temperature measuring thermocouple or alternatively infrared device 44. The signal from the thermocouple 44 is directed to the temperature controller 46 which in a conventional manner interprets the information and provides an appropriate signal to the power controller 46. Electrical current, as directed by the power controller 38 is supplied to the heaters 36 via the transformer 42. The transformer 42 is selected to provide the voltage to suit the characteristics of the particular heaters 36 used and the particular wiring configuration. Kanthal Super ST heaters are low resistance, high current heaters. If connected in parallel, such heaters use voltages between 10 and 20 volts and currents between 150 and 275 amperes to achieve the above noted temperatures.
As discussed above, the organic materials are converted in the chamber to carbon black and other atoms or small molecules, such as hydrogen and carbon monoxide. If inorganic materials, such as steel needles or staples, are included in the material being processed, the above noted operating temperatures in the reaction chamber 18 are below the melting point of these inorganic materials. These then will form a residue on the bottom of the chamber. This residue is, in turn, removed periodically through a specially provided port 48.
To facilitate removal of low melting inorganic materials that may be included in the materials being processed, a liner 50 is provided in the bottom of the chamber. This liner 50 must be resistant to corrosion by the molten inorganic materials. One such material is aluminum nitride, which can be formed into one piece inserts. With large amounts of molten materials, an overflow is provided with a conventional control valve, not shown, similar to that provided in glass furnaces. With small amounts of molten materials, the liner 50 and surrounding materials may be made to be removable so as to serve as a disposable container.
Alternately, if the operating temperature is increased, the steel will melt. In this case, the liner 50, as described above, will also be used to collect the molten materials.
As discussed above, the carbon typically forms as a porous solid. It passes out of the chamber 18 with the gases through a conduit 52. Upon exiting the chamber, air is added through a port 54 in the conduit 52 to cool the gases before they pass through the rest of the system. The carbon black is collected in a conventional cyclone and filter system shown generally at 56. Specifically, this system 56 includes a conventional cyclone or cyclones 58 and a conventional filter 62 that interconnect, via a conduit 64, so as to permit gases to flow from the cyclone(s) 58 to the filter 62. Carbon black collected in the cyclone(s) 58 and filter 62 pass through rotary valves 66 and 68, respectively, into a storage bin 72. The gases pass from the filter 62 to the chamber 58 by means of a conduit 74.
The other remaining gases pass from the filter 62 into and through a secondary reaction chamber 76. The gases are heated in that chamber 76, by a conventional heater 78, to a sufficient temperature to oxide any remaining carbon, carbon monoxide, and hydrogen.
A conventional scrubber 82 is provided downstream of the chamber 76 to remove any acid gases that may have been formed in that chamber. A conventional fan 84, located downstream of the scrubber 82, moves the gases into the atmosphere and maintains the chambers under negative pressure.
Alternatively and in small installations designed to eliminate organic wastes, all of the carbon produced in the reaction chamber 18 may be oxidized into carbon dioxide in a conventional secondary reactor 86, as shown in FIG. 2. The additional energy needed to oxidize is supplied by conventional electrical resistance heaters 88. The temperature in this reactor 86 is maintained high enough such that the complete oxidation of carbon black occurs, that is, greater than 550° C. The exhaust gases from the reactor 86 pass to and through a conventional scrubber and fan such as the scrubber 82 and fan 84.
If carbon black is to be produced from a liquid organic material, a conventional pump 92 is used to move this organic material into the reaction chamber 18. A conventional nozzle 94 may be used to disperse this liquid feed material, but the particle size of the spray cannot be small, as the particles of liquid must absorb infrared radiation. In this regard, the spray particles should be at least 100 microns in size. In all other aspects, the reactor 10 and downstream system 56 in the system function identically as when the feed material is solid.
The preferred embodiment of the present invention has now been described. This preferred embodiment constitutes the best mode presently contemplated by the inventor for carrying out his invention. Because the invention may be copied without copying the precise details of the preferred embodiment, the following claims particularly point out and distinctly claim the subject matter which the inventor regards as his invention and wishes to protect. | A method is described for photochemically decomposing organic materials into hydrogen gas and elemental carbon, preferably in the form of carbon black, and to a smaller extent carbon monoxide. The organic materials are induced to decompose primarily and solely through their exposure to a sufficiently intense field of radiant energy, for a sufficient time, in a substantially closed reactor. | 2 |
FIELD OF THE INVENTION
This application relates to operating systems and, more particularly, to a file system that validates an entity attempting a file access before allowing the entity to perform file operations.
BACKGROUND OF THE INVENTION
In recent years, the internet has become extremely popular. Using the internet, users can download files into the memory of their computers easily and cheaply. One problem with such a process is that the user has no way of knowing whether the party supplying the software is trustworthy. Software supplied from untrusted sources can contain unexpected "bugs" and might even be completely different from the software the user expects to receive. For example, software from untrusted sources may contain a computer virus that is not detected until the software is executed.
In fact, such problems can arise with any software or data obtained from outside sources. Computer programs and computer data files are normally stored on computer systems without the capability of automatically sensing that programs and data are 1) authentic and 2) unmolested. Conventional methods of checking for authenticity and noncorruption require action on the part of human beings. Application programs verify data by fixed checksums, both with and without cryptographic assurance. What is needed is a truly automatic and transparent method of checking and authenticating software and data in a computer system.
SUMMARY OF THE INVENTION
The present invention overcomes the problems and disadvantages of the prior art by providing a method and apparatus that allows a computer system to trust both program and data files without the intervention of the user and with a decreased possibility of circumventing the model of trust.
A preferred embodiment of the present invention includes two levels of validation for programs and data. A first level of validation specifies sources that the user has decided are trustworthy (or not trustworthy). A second level of validation specifies sources that the system itself considers trustworthy or untrustworthy. For data to be acceptable, it must be acceptable to both levels of checking. Thus, for example, if the user decides to accept all data from entity "A", but the system has decided not to accept all data from entity "A," the file system would not store data from entity "A." As a further example, if the user has decided to accept no data from "B", but the system has decided to accept all data from "B", then no data from "B" would be stored on the system.
In addition, a preferred embodiment of the present invention allows the user and the system to specify multiple acceptable signatures and further allows various ones of the multiple signatures to have different levels of access to the system (i.e., different permissions). A preferred embodiment the present invention can be implemented so as to be transparent to the user and to co-exist with existing file systems.
In accordance with the purpose of the invention, as embodied and broadly described herein, a preferred embodiment of the present invention is a method of performing a file access, comprising the steps, performed by a data processing system having a memory, of: receiving an indication that an entity desires to perform a file access operation on a file of the data processing system; obtaining an affidavit of the file; checking that the affidavit is acceptable in accordance with a user signature data structure stored in the memory; checking that the affidavit is acceptable in accordance with the system signature data structure stored in the memory; and allowing the file access operation when the affidavit is acceptable in accordance with both the user signature data structure and the system signature data structure.
In further accordance with the purpose of the invention, as embodied and broadly described herein, a preferred embodiment of the present invention is a method of creating a secure file, comprising the steps, performed by a data processing system having a memory, of: receiving an indication that an entity desires to perform a file access operation on a file of the data processing system; obtaining a private key of the entity; receiving data of the file to be created; determining a checksum of the file; encrypting the checksum using the private key, and creating the file and an associated affidavit that includes the encrypted checksum.
In further accordance with the present invention, as embodied and broadly described herein, a preferred embodiment of the present invention is: a signature data structure stored in a memory of a data processing system, comprising: a first entity field storing a name of an entity trusted to perform a file access; a first public key field storing a public key of the first entity; a second entity field storing a name of an entity trusted to perform a file access; and a second public key field storing a public key of the second entity.
Advantages of the invention will be set forth in part in the description which follows and in part will be obvious from the description or may be learned by practice of the invention. Advantages of the invention will be realized and attained by a combination of the elements particularly pointed out in the appended claims and equivalents.
BRIEF DESCRIPTION OF THE FIGURES
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and, together with the description, serve to explain the principles of the invention.
FIG. 1 is a block diagram of a computer system in accordance with a preferred embodiment of the present invention.
FIG. 2 is a block diagram showing a data flow of a preferred embodiment of the present invention.
FIG. 3 shows an example of a user signature data structure or a system signature data structure of FIG. 1.
FIGS. 4(a) and 4(b) are flow charts showing how files are checked against the user signature data and the system signature data.
FIG. 5 is a flow chart of steps used to create signed files in a preferred embodiment of the present invention.
FIG. 6 is a block diagram of another preferred embodiment of the present invention in which the majority of the operating system must be verified before the system can be booted.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
FIG. 1 is a block diagram of a computer system 100 in accordance with a preferred embodiment of the present invention. Computer system 100 is connected to line 106, which can be, for example, a LAN, a WAN, or an internet connection. Line 106 can also represent a wireless connection, such as a cellular network connection.
Computer system 100 includes a CPU 102; a primary storage 104; input/output lines 105; an input device 150, such as a keyboard or mouse; and a display device 160, such as a display terminal Primary storage 104 can include any type of computer storage including, without limitation, random access memory (RAM), read-only memory (ROM), and storage devices which include magnetic and optical storage media such as magnetic or optical disks. Computer system 100 further includes an input device 161 for reading a computer usable medium 162 having computer readable program code means embodied therein. Input device 161 is, for example, a disk drive.
Primary storage 104 includes a data structure 120 containing user signatures and a data structure 122 containing system signatures, as discussed below in connection with FIG. 2. Memory 104 also includes signature checking software 124, which is also discussed below.
A person of ordinary skill in the art will understand that memory 104 also contains additional information, such as application programs, operating systems, data, etc., which are not shown in the figure for the sake of clarity. It will be understood by a person of ordinary skill in the art that computer system 100 can also include numerous elements not shown in the figure for the sake of clarity, such as additional disk drives, keyboards, display devices, network connections, additional memory, additional CPUs, LANs, input/output lines, etc. A preferred embodiment of the invention runs under the Solaris operating system, Version 2.3 and higher. Solaris is a registered trademark of Sun Microsystems, Inc.
FIG. 2 is a block diagram showing a data flow in a preferred embodiment of the present invention. File 202 has an associated affidavit 206 (also called a "cryptographic Affidavit.") As a file 202 is received by the system, its affidavit is checked against the signatures in the user signature data structure 120 and in the system signature data structure 122. The file must pass both tests before it can be stored by the system.
File 202 contains two parts: a file portion 204, which contains executable programs or data, and an affidavit portion 206, which contains an encrypted checksum 210 and other administrative data 208. Administrative data 208 includes the real identity of the creator of the affidavit, identifiers or pointers to other associated affidavits, dates and times of creation and expiration of the affidavit, and identifies co-signers of the affidavit. In some implementations, affidavit 206 is a part of file 202 and in other implementations, affidavit 206 is a separate file that is associated with file portion 204. For example, affidavit 206 can be incorporated into some file formats as a comment line. Other file formats may allow the affidavit to be closely coupled to the file portion 204 in some known manner.
FIG. 3 shows an example of a signature data structure of FIG. 1. Both user signature data structures and system signature data structures preferably have the same organization, and the format of FIG. 3 is used for both. The user signature data structure-represents sources that the user has indicated are trustworthy and the system signature data structure represents sources that the system considers to be trustworthy. In the example, each entry in the signature data structure has a name of a trusted entity 302, a type 304 of the entry (e.g., single entry or indirect database entry), a public key 306, and a series of values 308 indicating the type or types of permissions the entity has for the system (e.g., create, delete, read, write, execute, etc.). Every file access (e.g., every file open and delete operation) is checked against both the user and system data structures by the file system before the file access is allowed by the file system.
FIGS. 4(a) and 4(b) are flow charts showing how files are checked against the user signature data and the system signature data by the file system. In the preferred embodiment, all files received by the system from an outside source must include an affidavit. Similarly, each file created and stored by the file system must have an associated affidavit. In some implementations, the affidavit is a part of the file. In other implementations, the affidavit is associated with the file. Thus, the affidavit of a file is checked whenever a file operation is performed for the file. For example, the affidavit is checked when the file is created or loaded into memory. The affidavit also is checked when the file is read from, written to, or deleted. Such a process serves two goals: 1) to protect the file system from outsiders who wish to compromise files and 2) to protect users of the system from accessing or relying on files that have been tampered with. It will be understood by persons of ordinary skill in the art that the steps of FIGS. 4(a) and 4(b) are performed by CPU 102 of FIG. 1 executing instructions of the file system/operating system that are stored in memory 104. The steps of FIGS. 4(a) and 4(b) preferably are performed each time a file access is requested
In step 402 of FIG. 4(a), the file system gets the encrypted checksum 206 associated with the file. In step 404, the file system repeats the calculation of the checksum for the file using any known checksum method that was used to determine the affidavit. Steps 406-412 are repeated for each entry in the user signature data structure (or until a match is found).
In step 408, the file system decrypts the encrypted checksum 214 of the affidavit using the public key of the current user signature data structure entry. Because the affidavit was created with the entity's private key, decryption of the affidavit using the entity's correct public key should yield a decrypted checksum for the file. Decryption using other public keys should yield an incorrect checksum
If in step 410, the decrypted checksum matches the checksum determined in step 404, then the affidavit represents an entity considered trustworthy by the user and the file has not been tampered with. Thus, control passes to FIG. 4(b). If no match is found after checking the entire user signature data structure, then the entity is not trusted and the file operation is denied.
Steps 420-426 are repeated for each entry in the system signature data structure (or until a match is found). In step 422, the file system decrypts the encrypted checksum 210 of affidavit 206 using the public key of the current system signature data structure entry. If, in step 424, the decrypted checksum matches the checksum determined in step 404, then the affidavit represents an entity considered trustworthy by the system and the file operation is allowed. If no match is found after checking the entire system signature data structure, then the entity is not trusted and the file operation is denied.
Some implementations of the present invention also include a "default" entry in one or more of their signature data structures. For example, as shown in FIG. 3, entry 320 contains the entity "any" and allows the entity permission to read files. Thus, if FIG. 3 represents the user signature data structure, the user has indicated that he gives permission to any entity to open a file in read-only mode. In this example, for such a file operation to actually be allowed by the file system, the system signature data structure must also allow the access. In yet another implementation, either of the signature data structures may contain a "not entity" entry, indicating that a certain entity is not allowed to make certain file accesses (even if an "any" entity is also present in one of the signature data structures).
The "type" field of FIG. 3 allows the signature data structure to reference public keys stored in another part of the system, such as in a data base or another signature data structure stored elsewhere on the computer. For example, users may share a common signature data structure. Thus, in FIG. 3, the user has decided to allow access by the entities owning all of the public keys in "Geoffs" database. In some implementations, the user must be an entity trusted by Geoffs database in order to access public keys therefrom.
In a preferred embodiment of the present invention, the encryption scheme used is the Digital Signature Algorithm (DSA), described in Schneier, "Applied Cryptography: Protocols, Algorithms, and Source Code in C," second edition, 1996, pp. 483-495, which is herein incorporated by reference. In another embodiment, the encryption scheme used is the SHA-1 scheme.
In a preferred embodiment of the present invention, one or both or the user signature data structure and the system signature data structure are stored on a PCMCIA card or some other removable storage medium. Thus, the user simply inserts his PCMCIA card to personalize the user and/or system signature data structures of the computer that he is working on. In such an implementation, of course, the file system must know that the signature data structures are so stored.
FIG. 5 is a flow chart of steps used to create signed files in a preferred embodiment of the present invention, when the files are created by the computer system 100. It, for example, files are created on another system and loaded into computer system 100 via the internet or a floppy disk or other portable or networked media, the files must have already been created and must have an affidavit associated therewith to be accepted by computer system 100. FIG. 5, however, deals with the situation when the user wishes to create a file on computer system 100.
In step 502, the system obtains a private key of the entity creating the file. This may be the user's private key if the user is creating the file directly or if the user is running software that creates a file (e.g., word processing software). In a preferred embodiment, the user is prompted for his private key and the user types his private key into the system or inserts a storage device on which his private key is stored. Alternately, private keys of users can be stored in a protected part of computer system 100. Alternately, a user may be required to enter a pin number before the system looks up the user's private key from a protected memory. In step 504, the file is created and written to storage, while the file system maintains a running checksum of the data in the file. A "running checksum" is a checksum that is continuously updated as the file is written. The system prevents file accesses by others while the file is being created. In some cases, portions of the file may be written to an external storage medium during file creation. This situation occurs, for example, when the created file is large.
It should be noted that a potential problem can occur if data is written to an external storage device during file creation, but the file creation operation is not completed. In this case, data will exist on the external storage medium, but the data will not have an associated affidavit. In a preferred embodiment, the file system is not allowed to access such files. Aborting the write/creation of the file before the affidavit is created causes the system to destroy the partially written file.
In step 506, the file system encrypts the checksum from step 504 using the user's private key and writes the checksum to the storage medium, either as a part of the file or associated with the file, depending on the implementation. Thus, all files created by the file system of the described embodiment have an associated affidavit. In a preferred embodiment, each time a file is written to, its checksum must be recompute and its affidavit recalculated using the private key of the creating entity. Some implementations wait until a file is closed before recomputing the affidavit. Again, a problem can arise if an error occurs during the write, but before the affidavit can be created and stored in association with the written file. Once a file is created, it can only be opened or deleted by an entity that passes the two-tier validation test of FIGS. 4(a) and 4(b).
In yet another embodiment, the system allows a user to create two types of files: verified and unverified files. Verified files are required to have an associated affidavit and are validated as described above for each file operation. Non-verified files do not require verification before each file operation In another preferred embodiment, files can be opened in either "verified" or "unverified" mode. In this embodiment, the file system would most likely have two "open" routines--one that requires verification of files that it opens and one that does not.
Files that are downloaded, e.g., over the internet or from a floppy disk, retain the affidavits that they had when they were received by the system must be preceded and accompanied by an affidavit.
FIG. 6 is a block diagram of another preferred embodiment of the present invention in which the majority of the runtime environment (e.g., an operating system or interpreter) must be verified as described above before the system can be booted. In FIG. 6, a small amount of program data is stored in a boot ROM 604. The CPU 602 loads a signature of the runtime environment and basic software for computing a checksum and decrypting an affidavit. At boot time, the remainder of the runtime environment is loaded from secondary mass storage 610, along with its affidavit (which is an encrypted checksum). The CPU computes the checksum of the runtime environment code as it is loaded and decrypts the affidavit using the public key from the boot ROM. If the checksum and the decrypted checksum match, the runtime environment load is completed. The loaded runtime environment includes the checking software 608, which is used as described in FIGS. 4(a), 4(b), and 5 during operation of the system.
In summary, the described embodiment of the present invention incorporates two or more levels or signatures. A file access must satisfy both levels before it is allowed by the file system. In addition, both the user and the system may specify multiple trusted entities that are allowed to perform file accesses in the system. Trusted entities are specified for the system, not on a file by file basis. Various entities, however, can have various permissions associated therewith.
Although the embodiments discussed involved "files" a person of ordinary skill in the art will understand that the present invention could also be implemented in an object oriented environment.
Other embodiments 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 of the invention being indicated by the following claims and equivalents. | A method and apparatus that allows a computer system to trust both program and data files without the intervention of the user and without the possibility of circumventing the model of trust. A file system incorporates two levels of validation for programs and data. A first level of validation specifies sources that the user has decided are trustworthy or untrustworthy. A second level of validation specifies sources that the system itself considers trustworthy or untrustworthy. For data to be acceptable, it must be acceptable to both levels of checking. In addition, both the user and the system can specify multiple acceptable signatures and further allows various ones of the multiple signatures to have different levels of access to the system. | 6 |
BACKGROUND OF THE INVENTION
This invention relates generally to paired heddles for weaving looms for the production of thickened warp in woven fabrics.
The heddles are paired on the weaving machine to facilitate the weaving of fabric with a heavy warp. Considering a single heddle pair, one of the two heddles is so shaped that its thread eye is positioned in a rear row, and the other heddle of the pair is so shaped that its thread eye is positioned in a forward row. Due to the offset of the thread eyes displaced from the center line of the frame bars on which the heddle pair is mounted upright, such arrangement assures that the passage for the warp even at the broadest part of the heddle, i.e., in the area of the thread eyes, is substantially increased.
Such heddles mounted in pairs are known in the art and are set forth in FIGS. 1, 2 and 9 of the drawings which will be described in more detail hereinafter.
Modern day weaving machines reach very high speeds of rotation resulting in that the loom shafts severely deform in operation because of the high dynamic loadings. This deformation reaches such a level that the play at which the heddles can arrange themselves orderly in a row on the heddle carrier bars of the loom shafts, disappears, and indeed is overcome. When the heddle play is overcome the heddles are stressed in tension along the length thereof. Heddles of modern design which are structured mainly to be symmetrical therefore are deformed into a shape which, at least partially, is inappropriate for the structural loads. Those heddles in the drawings designated 1 , 8 , 32 and 34 have a high degree of rigidity as compared with heddles 2 and 9 . As a result heddles 1 , 8 , 32 and 34 tend to rapidly deform under tension.
Shown in FIG. 1 is a prior art heddle pair comprising heddles 1 and 2 respectively having centrally located thread eyes 4 and 6 respectively lying along the central axis of that portion of each heddle body which comprises an elongated shaft. The open thread eyes at opposing ends of the shaft provide, as is known in the art, for mounting the heddles in overlying relationship on upper and lower frame bars and/or shafts of the weaving machine (not shown). Thus the thread eyes are offset, to the left and to the right, from the central axis of the frame extending through the upper and lower frame bars.
Heddles 1 and 2 each has a row hole 17 as well as a stamping 18 , as known in the art.
Similarly, the prior art heddle pair 8 , 9 shown in FIG. 2 is essentially the same as aforedescribed with respect to FIG. 1 except that the end eyes at opposing ends of the shaft of the heddle body of each heddle are C-shaped rather than J-shaped. Thus heddles 8 and 9 respectively contain thread eyes 4 and 5 midway between their ends. In operation, heddle 1 of the heddle pair 1 , 2 of FIG. 1 as well as heddle 8 of the heddle pair 8 , 9 of FIG. 2, each exhibit a high tensile rigidity in a lengthwise direction, but have a tendency toward rupturing lengthwise, while the other heddles of the pairs, i.e., 2 and 9 , respectively, remain undamaged under severe loadings. The reason for this difference in operational behavior could very well be attributed to the fact that the two heddles, 2 and 9 , in the area between the end eyes and the thread eyes, i.e., between the end eyes and the heddle shaft, exhibit more resilience as compared to their respective heddles 1 and 8 .
SUMMARY OF THE INVENTION
Considering the aforestated disadvantages, it is the object of this invention to provide a heddle, mounted in pairs, which for different types of heddle pairs have enhanced tensile strengths, i.e., a like modulus of elasticity for the heddles of each pair. In keeping with this objective care must be exercised in retaining the full capacity to function as modern heddles, i.e., the heddles must be capable of operating on current weaving machines, they must be transportable in the same manner as before, and they must be able to be installed on the same weaving frame shafts. In accordance with the invention, each heddle of a pair of heddles for a weaving machine comprises a body having an elongated shaft containing a thread eye, and for one type of heddle has open end eyes at opposing ends of the shaft. The end eyes open toward one side of the body. The heddle body of at least one heddle of the pair has a recess adjacent at least one of its end eyes, the recess opening outwardly at a side of the body opposite the one side toward which the thread eye opens. The recess is at a location between the adjacent end eye and the heddle shaft for increasing the resiliency of the heddle along the length thereof. For the heddle pair having closed end eyes at opposite ends of the shafts, the body of at least one heddle of the pair has a recess adjacent at least one of the end eyes opening toward an outer side of the pair. Such recess is likewise at a location between the adjacent end eye and the heddle shaft for increasing the resiliency of the heddle along the length thereof.
Thus the objective of the invention is achieved so that the area adjacent the end eyes of one or both heddles of the pair, which area is relatively rigid as to extension, is rendered spring-like resilient, specifically by shaping that area between the adjacent end eye and the heddle shaft.
Thus one or both heddles of the pair, at a location between the thread eye and its end eye, the nearer it approaches the end eye or the area of the end eye exhibits a change in shape, such as a recess or an inwardly bowed section. This area of the end eye is otherwise designed to be open.
The open recess provided at such location for one or both heddles of the pair in the area adjacent the end eye or eyes, may be in the form of a bowed portion which imparts a spring-like characteristic to that area.
Other objects, advantages and novel features of the invention will become more apparently from the following detailed description of the invention when taken into conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a pair of heddles according to the prior art having J-shaped end eyes;
FIG. 2 is a plan view of a pair of heddles according to the prior art having C-shaped end eyes;
FIG. 3 is a top plan view of a heddle pair incorporating the invention, each heddle having C-shaped end eyes;
FIG. 4 is a plan view of a heddle pair incorporating the invention with each heddle having C-shaped end eyes;
FIG. 5 is a top plan view of a heddle to be installed in pairs and incorporating the invention, the heddle having J-shaped end eyes;
FIGS. 6 - 8 is a view similar to FIG. 5 of another heddle incorporating the invention to be mounted as a pair and having J-shaped end eyes;
FIG. 9 is a top plan view of a pair of heddles according to the prior art having closed end eyes;
FIG. 10 is a top plan view of a heddle pair having closed end eyes and incorporating the invention; and
FIG. 11 is a top plan view of a heddle to be installed as a heddle pair incorporating the invention and having closed end eyes.
DETAILED DESCRIPTION OF THE INVENTION
The present invention has for its objective a manner of avoiding the drawbacks of prior art heddle pairs as discussed above, in that two heddles of the heddle pair, shown in FIGS. 3 and 4, for example, are designed to be resilient in a spring-like manner between their respectively end eyes and their thread eyes. This condition is achieved for heddle 23 of FIG. 3 by the provision of recesses 11 , 11 ′ respectively adjacent the thread eyes of the heddle and being at a location between that adjacent end eye and the thread eye of the heddle, i.e., between the adjacent end eye and the heddle shaft. Likewise heddle 28 of FIG. 4 has recesses 14 , 14 ′ respectively adjacent the end eye at opposite ends of the elongated shaft of the body of the heddle, and each recess being located between such adjacent end eye and the heddle shaft. The open end eyes of FIG. 3 open toward one side of the heddle body, and recesses 11 , 11 ′ according to the invention open outwardly at a side of the heddle body opposite the side toward which the end eyes open. Similarly opposing end eyes of heddle 28 of FIG. 4 open toward one side of the heddle body, while the recesses the 14 and 14 ′ of the invention open toward an opposite side of that body.
Similar recesses are provided for each of the other two heddles 22 and 19 of the pairs such that for heddle 22 , recesses 11 ″ and 11 ′″ are provided respectively adjacent the end eyes and at a location between their respective adjacent end eyes and the elongated shaft portion of the heddle. Likewise heddle 19 of FIG. 4 has recesses 14 ″ and 14 ′″ respectively adjacent the end eyes and at locations between the adjacent end eyes and the elongated shaft portion of the heddle. And the recesses for heddles 22 and 19 open toward a side opposite that side toward which the end eyes open. The recesses for these heddles provide spring-like resilience in the area between the respectively end eyes and the elongated shaft portion of the heddle.
Additional variants of heddles are presented in FIGS. 5, 6 , 7 and 8 , which respectively illustrate only 1 heddle of the pair since the other heddles for the respective pairs need not be illustrated, given that, as in heddles 2 , 9 , 22 , 19 , for the heddle pairs of FIGS. 1 to 4 , these heddles remain undamaged under high loads under most circumstances. All heddles illustrated in FIGS. 5 to 8 have a common feature, i.e., at a location between the end eyes and the elongated shaft portion of the heddle body recesses which may be in the form of inwardly bowed sections are formed such as 12 , 12 ′, 13 , 13 ′, 15 , 15 ′ and 16 , 16 ′. Each of these sections bow inwardly from the same side of the heddle which side is opposite that side of the respective heddles to which the end eyes open. Thus the bowed sections in effect open in a direction toward one side of the body of the heddle which is opposite that side to which the end eyes open.
Heddles 24 , 25 , 29 and 30 respectively of FIGS. 5 to 8 can be combined with other heddles, for example, such as heddle 9 being combinable with either of heddles 24 , 25 , or such as heddle 9 being combinable with either of heddles 29 and 30 . It can be therefore seen that when combining these heddles into pairs, their heddle designs can be utilized which more or less correspond to the 4 shown in FIGS. 5 to 8 . According to the invention if both heddles of the heddle pair are spring-like resilient or flexible in that area between the end eyes and the elongated shaft portion of the heddle in order to prevent damage at operations at a high load.
While the heddles shown in FIGS. 1 to 8 illustrate open end eyes, the invention is likewise adaptable for heddles of FIGS. 9 to 11 having closed end eyes such as 36 shown in FIG. 9 . Similarly as in heddles having open end eyes, the heddle of FIGS. 9, 10 and 11 having closed end eyes have thread eyes 4 ′, 6 ′ located in the middle of the heddle and respectively lying along the longitudinal axes of the elongated shafts of the heddles 1 and to the other side of central axis extending through the upper and lower heddle frame bars on which the heddle pairs are mounted, so as to be offset from that axis. Contrary to the heddle pairs shown in FIGS. 1 and 2, both heddles of the FIG. 9 pair exhibit high elongation rigidity such that upon a high loading both heddles tend to fracture under loadings. Accordingly, both heddles of the heddle pair are to be modified in accordance with the invention as, for example, shown in FIG. 10 . There heddles 38 and 40 have respective recesses in the form of inwardly bowed sections 37 , 37 ′ and 39 , 39 ′, respectively, which bowed sections open toward an outer side of the heddle pair. And the respective recesses are adjacent the end eyes of the pair as shown, and are at a location between that adjacent end eye and the thread eye, i.e., between the adjacent end eye and the elongated shaft section of the heddle body. By the provision of such recesses, the resiliency of the heddles of each pair are increased along the length thereof.
For those heddles which do not require a stamping 18 such as that shown in FIGS. 1 to 4 , which is required in order to be used on the entry machine, the heddles may be shaped as in FIGS. 6 or 8 , which the recesses 13 , 13 ′ and 16 , 16 ′ impart to the respective heddles a certain ideal form.
The aforedescribed recesses according to the invention may have a depth equal to at least one-half the width of the elongated shaft portion of the heddle.
Obviously, the shaping of the heddles in accordance with the invention is made possible for any type of a heddle intended for a paired installation. Thus all heddles lie within the limits of the invention, such as those heddles showing distortion, which separates the heddles from one another, those heddles with easily twisted thread eyes, those heddles which in the area of the thread eyes exhibit squeezing, or those heddles in which the end eyes demonstrate by compression a greater breadth than the breadth of the heddle itself, etc.
Thus the present invention is not limited to the examples shown in FIGS. 1 to 11 , but encompasses fundamentally every type of heddle to be used in paired arrangement and which are designed in accordance with the invention.
Obviously, many modifications and variations of the present invention are made possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | Weaving heddles, intended for paired operation, are rendered spring-like resilient in the areas adjacent the end eyes to prevent breakage of the heddles in operation by the high degree of dynamic loading. Such spring-like resiliency is achieved by a provision of a shape change, such as a recess or inwardly bowed section, in the heddles adjacent the end eyes and at a location between the adjacent end eyes and the elongated shaft section of the heddle body. | 3 |
FIELD OF THE INVENTION
The invention relates to a devices for attaching a side airbag, sometimes called a curtain airbag, to a vehicle or a vehicle structure. The invention further relates to an assembly of an airbag and a fastening device, such as a clamp for attaching a side airbag to a vehicle or a vehicle structure.
BACKGROUND OF THE INVENTION
Clamps are used in vehicle occupant restraint systems that include an airbag, to attach the airbag in the folded state to a vehicle structure, such as for example the vehicle body. The clamps are used in particular with side airbags, in which the airbag is attached in the folded state along the supporting structure of an automobile for example between the A and B pillars or the A and C pillars on the side facing the inside of the vehicle. A tube-like pouch may surround the folded airbag and, with an inflator, forms an airbag module.
DISCUSSION OF THE PRIOR ART
DE 200 20 097 U1 teaches a clamp for an airbag that has two metal arms. The two arms are connected by a head. They encompass a folded airbag on both sides, such that the airbag is held therebetween. The arms touch one another at the ends thereof remote from the head. When the airbag module is actuated, the airbag held by the clamp is filled very rapidly with gas. During this process, the arms of the clamp are bent apart with great force and at high speed, so that the airbag may pass between them and be deployed. The bending process may cause an arm to break off from the head.
Clamps are also known in which two arms are substantially connected to the end area of the clamp remote from a head by a hinge. The two arms are again connected to the head of such a clamp by a retaining screw that connects the head to a vehicle. The hinge between the two arms takes the form of a predetermined breaking point. When the airbag module is actuated, this predetermined breaking point is opened and the airbag exits between the arms, while one of the arms is again forced with great power out of its rest position or deformed.
SUMMARY OF THE INVENTION
There is provided in accordance with on aspect of the invention a device for attaching an airbag to a vehicle structure, the device comprising a head for attachment to the vehicle structure and at least one arm adjoining the head for holding the airbag, wherein the clamp is of one-armed construction and the one arm is so shaped that the folded airbag or a pouch containing the airbag is held at least partially between the single arm and the vehicle structure.
There is provided in accordance with another aspect of the invention an assembly comprising an airbag and an attachment device for attaching the airbag to a vehicle structure, the airbag being contained in a pouch, the attachment device comprising a head for attachment to the vehicle structure and at least one arm adjoining the head for holding the airbag, wherein the attachment device is a clamp is of one-armed construction and the one arm is so shaped that the folded airbag or the pouch containing the airbag is held at least partially between the single arm and the vehicle structure.
In known airbag clamp designs, a folded airbag is enclosed completely by two arms of a clamp and these two arms are moved apart during inflation of the airbag. According to the invention, on the other hand, a single arm is provided which is attached to the vehicle structure. The single arm holds the airbag or a pouch surrounding it relative to this vehicle structure. Upon deployment, the airbag attached in this way may either exit freely between the single arm and the adjoining vehicle structure or deploy freely at the side of the arm remote from the vehicle structure. An arm is neither bent open or deformed forcefully. Because bending open and deformation of clamp arms is prevented, less force is required for opening and inflating the airbag. This increases process reliability during opening.
According to the invention, a predetermined breaking point on the clamp is also avoided. Therefore, unintentional damage to the airbag or opening of a predetermined breaking point cannot happen either. The risk of such unintentional damage arose previously during production and assembly of a clamp or during actuation of the airbag.
The single arm provided according to the invention generally lies extensively against the vehicle structure and is thereby not exposed to any great load.
The shape of the clamp according to the invention may moreover be produced with little material and with relatively simple tools. Its production costs are therefore altogether lower than with known clamps.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal section through a first exemplary embodiment of a fastening device according to the invention.
FIG. 2 is a longitudinal section through a second exemplary embodiment of a fastening device according to the invention.
FIG. 3 is a front view of a vehicle occupant restraint system according to the invention with a plurality of above-mentioned fastening devices.
FIG. 4 is a perspective view of a detail of a folded airbag with pouch, as used in the above-mentioned first exemplary embodiment.
FIG. 5 is a perspective view of a detail of a folded airbag with pouch, as used in the above-mentioned second exemplary embodiment.
FIG. 6 is a perspective view of an exemplary embodiment of a clamp according to the invention with a folded-open head.
FIG. 7 is a perspective view according to FIG. 6 of the clamp with a closed head.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 to 7 show devices 10 for attaching or fastening an airbag 36 in particular a side airbag, that is part of a vehicle occupant restraint system to a vehicle structure 12 . Put another way, FIGS. 1 to 7 show exemplary assemblies of an airbag 36 and an attachment device 14 for attaching the airbag to a vehicle structure 12 , the airbag being contained in a pouch 38 . The vehicle occupant restraint system is located inside a vehicle such that it will be in the vicinity of the head of a vehicle occupant.
The fastening device 10 according to FIG. 1 is provided with a clamp 14 , which comprises a head 16 and a single arm 18 adjoining the head 16 . The head 16 is subdivided into a first head portion 20 and a second head portion 22 , which may be folded relative to one another by a deformable hinge portion 24 and between which, in the folded-together state, there may be held a flap on the airbag or an airbag flap together with an additional flap on a pouch containing the folded airbag. The arm 18 extends from the second head portion 22 , which is spaced from the vehicle structure 12 by the first head portion 20 . Two through-holes 26 , 28 are formed centrally in the head portions 20 , 22 . The two through-holes 26 , 28 are arranged coaxially when the first and second head portions 20 , 22 are folded together. A screw 30 passes through the through-holes 26 , 28 beneath the head of which screw 30 there is positioned a washer 32 . The screw 30 is screwed into a socket 34 in the vehicle structure 12 and thereby mounts the clamp 14 on the vehicle structure 12 , which is represented by a phantom line. By means of the flap or flaps attached in this way, a secure and lasting connection is achieved between the vehicle structure and the airbag. The connection remains reliably in existence even in the case of opening or inflation of the airbag.
The fastening device according to the invention for an airbag may advantageously be designed with a pouch 38 containing the airbag 36 , into which pouch the single arm 18 of the clamp 14 projects. The arm thus grips the pouch so-to-speak from the inside out and is supported relative to the vehicle structure 12 . In this way, the pouch “hangs” on the single arm according to the invention.
The fastening device 10 is attached to a portion of the vehicle structure 12 that comprises a substantially vertical and a substantially horizontal, downwardly directed area. The screw 30 attaches the head 16 to the vertical area of the vehicle structure 12 . The single arm 18 extending from and adjoining the head 16 is bent along the substantially horizontal, downwardly directed area and extends substantially parallel to the vehicle structure 12 .
A folded airbag 36 is mounted on the arm 18 . The airbag 36 is arranged between the arm 18 and a substantially horizontal area of the vehicle structure 12 . The airbag 36 is contained in a pouch 38 , in which it is tightly packed. The pouch 38 is provided with an opening 40 , through which the arm 18 projects into the pouch 38 .
Alternatively or in addition, a flap 42 may be provided on the airbag itself, which is held between two retaining portions of the head of the clamp. The flap 42 is formed on the airbag 36 , in the center of which flap there is punched a hole 44 . The flap 42 passes beside the arm 18 through the opening 40 to the head 16 of the clamp 14 . The flap extends between the two head portions 20 , 22 as far as the vicinity of the hinge portion 24 . Between the two head portions 20 , 22 the flap 42 of the airbag 36 is clamped in a non-interlocking manner on both sides by means of the screw 30 . The screw 30 additionally passes through the hole 44 in the flap 42 , such that an interlocking connection is also provided between screw and airbag.
FIG. 2 shows an exemplary embodiment of a fastening device 10 that is constructed to a considerable extent in the same way as the fastening device according to FIG. 1 . In this exemplary embodiment, the head 16 of the clamp 14 again consists of two head portions 20 , 22 . However, in this exemplary embodiment the arm 18 starts from the head portion 20 , which lies against the vehicle structure 12 .
In order further to improve mounting of the clamp and an associated folded airbag, a prefixing means, in particular a prefixing pin 46 , is advantageously provided on the arm 18 for preliminary attachment of the clamp to or pre-mounting thereof on the vehicle. With the prefixing means, the clamp may be clipped to the vehicle structure, until for example the flap has been arranged between the head portions of the clamp and fastened by a screw 30 . The arm 18 again extends substantially parallel to the surface of the vehicle structure 12 . In its area remote from the head 16 , the arm 18 is connected to the vehicle structure 12 by a prefixing pin 46 . The connection using the prefixing pin 46 is effected during mounting of the clamp 14 , before a screw 30 is screwed into the head portions 20 , 22 through the corresponding through-holes 26 , 28 .
In the exemplary embodiment according to FIG. 2, the arm 18 is again inserted into the pouch 38 through an opening 40 . However, the opening 40 is formed in this case on the side or edge of the pouch 38 facing the vehicle structure 12 .
A second opening 48 is formed in the pouch 38 , through which opening 48 the prefixing pin 46 passes. In addition, in the exemplary embodiment according to FIG. 2, the flap 42 is again formed on the airbag 36 . An additional flap 42 ′ may be formed on the pouch 38 (see also FIG. 5 ), which would then be arranged together with the flap 42 likewise at the head 16 .
The arm 18 is inserted into the pouch 38 in such a way that the airbag 36 comes to lie against the side of the arm 18 remote from the vehicle structure 12 . Finally, at the end of the arm 18 remote from the head 16 there are also formed two hooks 50 , which engage the pouch 38 from inside in an interlocking manner prevent the arm 18 from sliding out of the pouch 38 . In addition, a hook for gripping part of the airbag or a pouch containing the folded airbag from behind is advantageously provided on the single arm. The hooks result in an interlocking connection between the airbag or the pouch and the vehicle structure. Detachment of the airbag from the vehicle is reliably prevented with this type of connection.
FIG. 3 shows the overall arrangement consisting of airbag 36 with pouch 38 and clamps 14 , as attached to a vehicle structure in the head area of a vehicle occupant. An inflator 52 , with which the airbag 36 is inflated in a safety-critical situation, is arranged at one end of the airbag 36 folded in the manner of a tube. Alternatively or in addition, a flap may be provided on the airbag itself, which is held between two retaining portions of the head of the clamp.
In addition to the above-mentioned flap for fastening the airbag, an additional flap may be provided particularly advantageously on such a pouch containing the airbag. The additional flap may likewise be held permanently between two retaining portions of the head of the clamp.
FIGS. 4 and 5 show in detail how the flaps 42 , 42 ′ are formed on an airbag 36 or on a pouch 38 .
The flap 42 according to FIG. 4 is attached to the airbag 36 and passes outwards through an oblong opening 40 in the pouch 38 . The pouch 38 is laid tightly around the airbag 36 and closed in the manner of a tube by a seam 54 . When the airbag 36 is inflated by the inflator 52 , the seam 54 is torn open and the airbag 36 is deployed out of the pouch 38 . In the exemplary embodiment according to FIG. 1, it passes downwards out of the gap between the arm 18 and the vehicle structure 12 .
FIG. 5 shows an exemplary embodiment in which an additional flap 42 ′ is provided on the pouch 38 beside the flap 42 (not illustrated) on the airbag 36 . The additional flap 42 ′ is formed out of the fabric of the pouch 38 , wherein an opening 40 ′ is formed. The opening 40 ′ may be formed particularly simply and economically at the additional flap in the airbag containing pouch by cutting the additional flap out of the pouch. In this way, in only one step, the flap is cut out and at the same time the opening is formed through which the single arm according to the invention is subsequently introduced into the pouch.
The opening 40 ′ corresponds in function to the opening 40 , such that the arm 18 may subsequently be pushed therethrough into the pouch 38 . The flap 42 ′ comprises a hole 44 ′ therethrough, as does the flap 42 on the airbag 36 . When the flap 42 ′ is arranged at the head 16 , the shank of the screw 30 is passed through this hole 44 ′ and the flap 42 ′ is attached in this way beside the flap 42 between the head portions 20 , 22 . Thus the pouch can be gripped “from the inside out” by means of the single arm 18 such the single arm of the clamp projects into the pouch. The flap then extends directly in the vicinity of the arm along the clamp to the head thereof. Thus, a compact and permanent connection is formed between clamp, pouch and folded airbag.
FIGS. 6 and 7 are perspective, detailed views of a clamp. Of particular note is the tapered hinge portion 24 between the two head portions 20 , 22 . In addition, the hooks 50 are formed in such a way that they project outwards to the sides. In the case of the clamp 14 according to FIGS. 6 and 7, the prefixing pin 46 may be arranged displaceably in channels 56 , in order to allow post-adjustment of the clamp 14 on the vehicle structure 12 prior to screwing in of the screw 30 .
While there have been described what are believed to be the preferred embodiments of the present invention, those skilled in the art will recognize that other and further changes and modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the true scope of the invention. | A clamp for attaching a folded airbag constituting part of a vehicle occupant restraint system to a vehicle structure has a head for attachment to the vehicle structure and at least one arm adjoining the head for holding the airbag. To prevent an arm being broken away from a clamp, the clamp is of one-armed construction and the one arm is so shaped that the folded airbag, or a pouch containing it, is held at least partially between the single arm and the vehicle structure. | 1 |
[0001] The present invention claims priority to U.S. provisional patent application No. 62/016,936 filed on Jun. 25, 2014, having inventors David Ronald Foxcroft and Gareth Edwards.
FIELD OF THE INVENTION
[0002] The present concept relates to coaching boards and more particularly relates to coaching boards which include a 3-dimensional perspective view of the playing surface.
BACKGROUND OF THE INVENTION
[0003] Within sporting situations Athletic Instructors and Coaches are called upon to deliver clear directives to their participants. These directives often include positioning, coordinating and moving multiple participants relative to one another on the playing surface. These directives may further include coordination of a ball, puck or other sporting equipment to implement a strategy.
[0004] Presently, this coordination is either delivered through oral instruction, manually positioning players on the surface of play, or through a scaled coaching aid such as a miniature model or coaching board.
[0005] These coaching boards minimize the number of independent parts and are often favored by coaches over miniature models for that reason. The boards further appear in various sizing from standard letter paper (8.5 by 11 inches) clip boards, slightly larger carry boards to large wall mounted surfaces. Additionally, these boards typically allow for erasable content on a blank surface or a surface with a two dimensional aerial view of a playing surface showing major markings scaled down appropriately.
[0006] The benefit of a pre-printed two dimensional aerial image of a playing surface is that the instructor is not required to recreate the playing surface every time a new scheme is to be drawn as the playing surface is not erased along with the previous erasable content.
[0007] The limitation of a two dimensional image of a playing surface on coaching aids is that it does not accurately represent the perspective participants have when they are physically on the playing surface. Specifically the depth of play.
[0008] Additionally, the lack of a third dimension prevents instructors from visually delivering directives in the third dimension of play present in many athletic events. For example: a two dimensional board is incompatible with visual directives to play a volleyball to a certain height over the net during a volleyball match.
[0009] Therefore there is a need for a coaching aid that better represents the depth of play a participant would encounter and also a need to facilitate instruction in the third dimension of play.
SUMMARY OF THE INVENTION
[0010] The present concept of a 3-Dimensional Coaching Board having a realistic color, texture and layout designed to display a playing surface that is better representative of a participant's real-world experience, and unexpectedly allows one to develop a strategy and give meaningful directives in the vertical direction of the playing surface.
[0011] The present concept of 3-dimensional coaching boards have a life-like playing surfaces. For example: the playing surface of the sport of hockey, a hockey rink, appears as a blue color with major marking lines to show skate marks on the ice; or the playing surface for the sport of soccer, a soccer field, shows a true to life grass texture.
[0012] The 3-Dimensional Coaching Board Concept shows a 3 dimensional image allowing for instruction in three dimensions and provides participants with a consistent experience in both teaching and practice.
[0013] The 3-dimensional image is especially important for teaching as it allows instructors to provide a more relevant and genuine demonstration compared to two dimensional images which force participants to rely on their own perception of depth once on the surface of play.
[0014] The present concept a coaching board in combination with an image displayed thereon, the combination comprising:
a) a planar coaching board with at least one erasable writing surface; b) a 3-D image displayed on the erasable writing surface, the 3-D image is a graphic depiction of a sports playing area and includes both horizontal features and vertical features in a perspective view; c) wherein the 3-D image is a perspective view of at least a portion of the playing area shown at a viewing angle of approximately 15° to 85° relative the horizontal.
[0018] Preferably wherein the sports playing area is chosen from among ice hockey rink, baseball diamond, volleyball court, American football field, soccer pitch, and basketball court.
[0019] Preferably wherein the horizontal feature includes a playing surface.
[0020] Preferably wherein the playing surface is chosen from among, ice surface, basketball court, volleyball court, baseball diamond, soccer pitch, football field, and basketball court.
[0021] Preferably wherein the vertical features is chosen from among, hockey boards, hockey safety glass, hockey net, soccer net, basketball net, football uprights, volleyball net, and baseball back walls.
[0022] Preferably wherein the 3-D image is a perspective view of at least a portion of the play surface shown at an angle of approximately 35° to 55° relative the horizontal.
[0023] Preferably wherein the playing surface including horizontal features selected from among boundary lines, face off circles, designated areas, and bases.
[0024] Preferably wherein the planar coaching board including a clip board.
[0025] Preferably wherein the planar coaching board includes a carry board.
[0026] Preferably wherein the planar coaching board includes a wallboard.
[0027] Preferably wherein at least one half of playing area is depicted on the planar coaching board.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The present concept will now be described by way of example only with reference to the following drawings in which:
[0029] FIG. 1 is a schematic plan view of a back face of a clipboard displaying a partial 3-Dimensional image of a hockey rink.
[0030] FIG. 2 is a schematic plan view of a front face of a clip board displaying a 2-dimensional image of a hockey playing surface.
[0031] FIG. 3 is a schematic plan view of a back face of a clipboard displaying a partial 3-D image of a hockey rink at a 20 degree angle relative to the horizontal.
[0032] FIG. 4 is a schematic plan view of a back face of a clipboard displaying a partial 3-D image of a hockey rink at a 45 degree angle relative to the horizontal.
[0033] FIG. 5 is a schematic plan view of a back face of a clipboard displaying a partial 3-D image of a hockey rink at a 85 degree angle relative to the horizontal.
[0034] FIG. 6 is a schematic plan view of a back face of a carry board displaying a partial 3-D image of a football field at a 45 degree angle relative to the horizontal.
[0035] FIG. 7 is a schematic plan view of a back face of a carry board displaying a partial 3-D image of a volleyball court at a 45 degree angle relative to the horizontal.
[0036] FIG. 8 is a schematic plan view of a back face of a carry board displaying a partial 3-D image of a basketball court at a 45 degree angle relative to the horizontal.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The present concept a 3-dimensional coaching board is shown generally as 100 in FIG. 1 . Coaching board 100 may be a clip board, a larger carry board or a very large wall board. In each case the coaching board 100 includes at least one surface which is an erasable writing surface such as a dry erase white board.
[0038] FIG. 1 shows a planar coaching board which in this example is clipboard back face 102 which is an erasable writing surface of a clipboard 101 which has a clipboard periphery 104 and as well shows clipboard fasteners 106 . Clipboard fasteners 106 are normally rivets however they may be any fastening means that are used in the art for fastening the clip mechanism 107 shown in FIG. 2 to the clipboard 101 .
[0039] The planar coaching board may be a clip board, a carry board as depicted in FIGS. 6 , 7 and 8 or a wallboard which generally is a planar surface mounted onto a wall. These boards would have at least one dry erasable surface upon which the 3-D image is depicted.
[0040] Depicted on the clipboard back face 102 is a graphic which includes a playing area which in this case is a three dimensional partial depiction of a hockey rink 110 on a two dimensional surface referred to as 3-D image 108 .
[0041] 3-D image 108 is a schematic partial view of hockey rink 110 and includes the entire neutral zone 112 as well as the attacking zone 114 . The reader will note that the attacking zone could also be the defending zone depending upon the direction of play. In other words 3-dimensional board 100 could be used to show players that are attacking net 120 or for showing players that are defending net 120 .
[0042] 3-D image 108 of hockey rink 110 depict the following features of ice playing surface 122 namely attackers blue line 116 , defenders blue line 124 , center face-off spot 126 , center face-off circle 128 , referees crease 130 , face off spots 132 and center line 134 .
[0043] 3-D image 108 also shows an attacking zone 114 , face off spots 136 , face-off circle 138 , goal line 140 , net 120 , goalie restricted area 142 which is sometimes also called the trapezoid as well as goal crease 144 .
[0044] 3-D image depicts horizontal features such as the ice playing surface 122 face off circles 138 and 126 and also vertical features such as the backboard 150 , the side boards 146 , and the side and back safety glass 148 and 152 .
[0045] 3-D Image 108 also shows peripheral area 111 which includes side boards 146 , side safety glass 148 , back boards 150 and back safety glass 152 .
[0046] Referring now to FIG. 2 which shows a 2-D image 160 of a hockey playing surface 162 on clipboard front face 164 as well as clip board periphery 104 of clipboard 101 .
[0047] FIG. 2 also shows clipping mechanism 107 as well as the front portion of clip fasteners 106 .
[0048] Referring now to FIGS. 3 , 4 and 5 which show schematically a plan view of a back-face of clipboard displaying a partial 3-D image of a hockey rink at different viewing angles relative to the horizontal.
[0049] FIG. 3 for example shows the hockey rink 110 at a viewing angle of 20 degrees relative to the horizontal and the reader will take reference to the back height 302 of the rink length 304 the circle depth 306 and the circle width 308 .
[0050] In FIG. 4 the back height is shown as 312 , the rink length 314 , the circle depth 314 , the circle depth 316 , and the circle width 318 . FIG. 4 shows the hockey rink 110 at an angle of about 45 degrees.
[0051] In FIG. 5 the back height is shown as 322 , the rink length as 324 , circle depth as 326 and the circle width at 328 . FIG. 5 shows the hockey rink 110 at an angle of about 85 degrees.
[0052] As the viewing angle is lower relative to the horizontal for example at 20 degrees there is significant compression of the rink length 304 and distortion of the centre face-off circle 128 due to the compression of horizontal features. Centre face-off circle 128 actually appears as an ellipse due to the distortion wherein the circle depth 306 is significantly less than the circle width 308 . Additionally the entire rink length 304 is also compressed. Vertical features such as back height 302 however is less distorted since the angle is only 20 degrees from the horizontal and back height 302 almost appears proportionally as the normal height. Back height 302 is comprised of backboard 150 and back safety glass 152 .
[0053] Comparing FIG. 3 to FIGS. 4 and 5 one will note that as the viewing angle increases from 20 to 45 and then to 85 the back height 312 in two dimensions decreases significantly such that the back height becomes very small at an 85 degree angle.
[0054] In contrast the rink length 314 and 324 increases on the two dimensional clipboard surface relative to rink length 304 shown in FIG. 3 as the angle increase from 45 degrees to 85 degrees.
[0055] Centre faceoff circle 128 at the 45 degree viewing angle still appears somewhat elliptical wherein the circle depth 316 is less than the circle width 128 however the rink length 314 is somewhat longer and the back height 312 is somewhat less than back height 302 , on the two dimensional clipboard surface.
[0056] Looking however at the 85 degree viewing angle one will see that the back height 322 has diminished significantly however the centre faceoff circle 128 now looks almost completely circular wherein the circle depth 326 is very close to the circle width 328 and the rink length 324 is at a maximum compared to the other views.
[0057] Therefore in summary at a small viewing angle such as 20 degrees or less there will be significant distortion of the horizontal features shown in the diagram in particular the ice playing surface 122 is length compressed such that the rink length 304 appears shorter and the centre faceoff circle 128 appears more of an ellipse than a circle. The vertical portions of the drawing however such as the backboards 150 and the back safety glass 152 will look more normal and have a relatively normal back height 302 , at 20 degrees as in FIG. 3 .
[0058] At the 45 degree angle there is some distortion of both the back height 312 and the rink length 314 and the centre faceoff circle 128 however the distortion in both the horizontal and the vertical portions is not extreme.
[0059] In FIG. 5 for example the back height 322 of back safety glass 152 and back boards 150 is extremely compressed and distorted however the rink length 324 and the centre faceoff circle 128 are less distorted wherein the circle depth 326 compared to the circle width 128 looks more circular and normal.
[0060] Therefore in selecting a viewing angle for 3-D image 108 one can see that at a very low viewing angle such as 20 degrees shown in FIG. 3 the ice playing surface 122 is badly distorted however the back safety glass 152 and back board 150 is less distorted. At the other extreme for example at a very high viewing angle relative to the horizontal namely 85 degrees shown in FIG. 5 one will see that the back height 322 is compressed and distorted namely the back safety glass 152 and the back boards 150 appear compressed and short whereas the ice playing surface 122 appears normal having a relatively normal looking rink length and centre faceoff circle.
[0061] The viewing angle of 45 degrees relative to the horizontal depicts a compromise between distortion of the horizontal features of the playing surface namely the ice playing surface 122 and distortion of the vertical features shown in the diagrams namely the backboard and the back safety glass 152 .
[0062] In practice it has been found by the inventor that an angle somewhere between 20 and 80 degrees in usable however the most usable range is roughly between 30 and 70 degrees and the most preferred viewing angle is between 35 degrees and 55 degrees
In Use
[0063] 3-D image 108 has a number of advantages over for example 2-D image 160 shown in FIG. 2 . 3-D image 108 shown in FIG. 1 allows for better depth perception and helps the user visualize the location on the ice. In other words there is a better feel for location and depth with the use of 3-D image 108 as opposed to a 2-D image 160 as shown in FIG. 2 .
[0064] With the use of a 2-D image 160 it is only possible to give a 2-D direction such as to show a 2-D shot and/or instructions in other words on the plane of the ice, in the present example.
[0065] With the use of 3-D image 108 shown in FIG. 1 it is possible to show not only shot direction and location on for example ice playing surface 122 but one could also show for example use of a shot off of back board 150 , off of back safety glass 152 , off of side boards 146 and/or off of side safety glass 148 . One could for example depict the height and location of the shot on the side 146 or backboards 150 to have the puck rebound to a certain location. These are shots which may in fact be used from time to time depending upon the situation that a team is confronted with. For example it is possible that one may want to use the safety glass 148 or 152 or for example the boards 150 or 146 in attempting to clear out a puck from your own end when you are confronted with a power play situation. It may be possible that one also wants to put the puck off of the back safety glass 152 near the net 120 in order to obtain a rebound which comes just in front of goal crease 144 of net 120 . These types of shots are difficult or impossible to depict with a 2-D image 160 shown in FIG. 2 however are very possible and easily shown and depicted with 3-D image 108 as shown in FIG. 1 .
[0066] It should be apparent to persons skilled in the arts that various modifications and adaptation of this structure described above are possible without departure from the spirit of the invention the scope of which defined in the appended claim. | The present concept is a coaching board in combination with an image displayed thereon. The combination includes a planar coaching board with at least one erasable writing surface and a 3-D image displayed on the erasable writing surface. The 3-D image is a graphic depiction of a sports playing area and includes horizontal and vertical features. The image is a perspective view of at least a portion of the playing area shown at an angle of approximately 15° to 85° relative to the horizontal. The sports playing area is chosen from among ice hockey rink, baseball diamond, volleyball court, American football field, soccer pitch, and basketball court. | 6 |
FIELD
[0001] The disclosure generally relates to computer systems administration, and more in particular to a system and method for network image propagation (e.g., propagating application images across a logically partitioned terminal) without a pre-configured network and without having to setup an network installation master.
BACKGROUND
[0002] Server administration is a major issue at many businesses with servers running plural logical partitions (LPARs). Each LPAR needs to be installed, backed up and maintained e.g., restored) from time to time. It normally takes several hours just to install one LPAR from scratch. In addition, cost effectiveness for backups and/or restores becomes a major concern when dealing with multiple LPAR clients. Current methods of installing, restoring and/or backing up applications to/from several LPARs are time consuming and costly.
[0003] For Example, in some conventional networks, a network installation manager (NIM) is utilized to provide network installations. NIM for AIX (Advanced Interactive executive) sold by International Business Machines (IBM) Corporation is an example of an application used for network image propagation (e.g., installing applications on plural LPARs). NIM installation methods include: configuring a NIM master either internal or external to a frame of LPARs to be installed, configuring a inter-LPAR network on the frame, and performing image application propagation to each LPAR via the inter-LPAR network.
[0004] Setting up a NIM master involves various tasks including: (a) installing NIM file sets, (b) configuring basic resources, (c) creating machine and network definitions, and (d) allocating resources that are used to install the needed machines. In addition, the NIM master has certain minimum requirements. For example, the NIM master requires access to sufficient memory and processor power along with a fast network and access to some kind of installation media. The NIM master also requires sufficient disk space to provide storage space for the necessary resources for the client LPARs, as well as for the backups of their volume groups containing the basic operating system (rootvgs). In the foregoing NIM environment, the LPAR with the resources is also commonly referred to as the VIO (virtual I/O) Server and the other LPARs using it are referred to VIO clients or LPAR clients.
[0005] In order to establish and run a NIM master, there are many NIM resources that need to be defined prior to the installing/propagating of applications from to the NIM master to the LPAR clients. NIM resources are defined in a NIM database on the NIM master (VIO server). Some of the NIM resources include:
[0006] lpp_source: The Licensed Program Product source (lpp_source) directory contains the images that the OS (e.g., AIX) uses to load software. These are typically the backup file format (BFF) images that exist on the OS installation CDs or DVD. Each OS version should have its own lpp_source.
[0007] SPOT: The Shared Product Object Tree (SPOT) is a directory created from the lpp_source. The SPOT is used in a similar fashion to the boot images and installation scripts on the base installation CD (e.g., volume one for AIX). It may be necessary to create multiple SPOTs depending on the installation/maintenance levels and versions that must be supported.
[0008] Mksysb: A method for backing up the OS. The NIM master can use lpp_source to install an instance, or it can install the instance from a mksysb of either that instance or another one. An instance as used herein refers to an OS image.
[0009] Scripts: Scripts can be set to run during a BOS (basic operating system) install to ensure that the resulting instance of the OS is correctly tailored with any post-installation items. These can include security requirements, third-party software installation and other customizations related to additional paging or dump space.
[0010] bosinst_data: This is a file that contains the necessary information to allow the installation to take place without manual intervention. It is used to define defaults such as default disk drive, type of installation, or the like.
[0011] image_data: This file contains OS image information related to file systems, mirroring, or the like.
[0012] installp_bundles: These are files that list additional software to be loaded after the BOS is installed. This can be useful when setting up groups of servers. As an example, one bundle may be for DB2 servers, while another may be for Web servers. Once the OS is installed, a desired post-install bundle may be installed in the same fashion as the BOS.
[0013] Accordingly, it would be highly desirable to perform installation/propagation of applications (e.g. BOS installs, mksysb restores, system backups, or the like) across a logically partitioned computer system over a virtual network with no-predefined network and without the need to configure a NIM master. Thus, advantageously providing a system, method and/or computer program product for mass network installation with minimal installer configuration overhead.
SUMMARY
[0014] The following examples provide a system and a method for automatically installing (also referred herein as “propagating”) application images across a logically partitioned computer system without a pre-configured network and with minimal installer configuration overhead. Exemplary embodiments of this disclosure would advantageously enable a user to automatically configure a temporary virtual inter-LPAR network, by temporary assigning virtual DP (internet protocol) and/or MAC (media access control) addresses solely for the purpose of installing (propagating) application images (e.g. BOS installs, mksysb restores, system backups, or the like) onto a plurality of LPARs. Upon successful installation, the temporary IP and/or MAC addresses would then be erased (deconfiguring the virtual network), and the newly installed LPARs would be assigned externally addressable (i.e. physical network) IP and/or MAC addresses through suitable network configuration methods.
[0015] In accordance with at least one disclosed example, a method for propagating applications in a logically partitioned terminal comprises: identifying a plurality of logical partitions residing in the logically partitioned terminal; configuring a temporary virtual network to connect said plurality of logical partitions to each other, wherein each one of the logical partitions is assigned at least one of a virtual Internet Protocol (IP) address and a virtual Media Access Control (MAC) address; installing an application image on at least one of the logical partitions via the temporary virtual network; deconfiguring the temporary virtual network; and assigning at least one of a physical IP address and a physical MAC address to said at least one logical partition on which the application has been installed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic diagram of an exemplary logically partitioned environment where the present invention may be practiced.
[0017] FIG. 2 is a schematic flowchart of an exemplary process performed for propagating application images from a computer readable media onto each of a plurality of LPARs.
DETAILED DESCRIPTION
[0018] In the following description of the various examples, reference is made to the accompanying drawings which are illustrations of various embodiments in which the system and method may be practiced. It is to be understood, however, that those skilled in the art may develop other structural and functional modifications without departing from the scope of the instant disclosure.
[0019] In the following description, specific details are set forth in order to provide a thorough understanding of the examples disclosed. In other instances, well-known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily lengthen the present disclosure. Some embodiments of the present invention may be practiced on a computer system that includes, in general, one or a plurality of processors for processing information and instructions, random access (volatile) memory (RAM) for storing information and instructions, read-only (non-volatile) memory (ROM) for storing static information and instructions, a data storage device such as a magnetic or optical disk and disk drive for storing information and instructions, an optional user output device such as a display device (e.g., a monitor) for displaying information to the computer user, an optional user input device including alphanumeric and function keys (e.g., a keyboard) for communicating information and command selections to the processor, and an optional user input device such as a cursor control device (e.g., a mouse) for communicating user input information and command selections to the processor.
[0020] As will be appreciated by those skilled in the art, the present examples may be embodied as a system, method or computer program product. Accordingly, some examples may take the form of an entirely hardware embodiment, and entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred herein as a “circuit”, “module” or “system”. Further, some embodiments may take the form of a computer program product embodied in any tangible medium of expression having computer-usable program code stored therein. For example, some embodiments described below with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products can be implemented by computer program instructions. The computer program instructions may be stored in computer-readable media that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable media constitute an article of manufacture including instructions and processes which implement the function/act/step specified in the flowchart and/or block diagram.
[0021] Referring now to the drawings, wherein like reference numerals refer to like parts, FIG. 1 is a block diagram illustrating an exemplary logically partioned computer system 100 , which may appropriately be referred also as an “LPAR terminal.” In accordance with at least one illustrative embodiment disclosed herein, computer system 100 may be implemented using various commercially available computer systems. For example, any one of an IBM AS/400 computer system or an enhanced IBM eServer iSeries computer system represents one suitable type of computer system that supports logical portioning and may be used to practice the disclosed examples. FIG. 1 is intended as an illustration only, and not as an architectural limitation for the present disclosure. Accordingly, those skilled in the art will appreciate that the mechanisms and apparatus disclosed herein apply equally to any computer system that supports logical partitions.
[0022] As illustrated in FIG. 1 , this example of a computer system 100 comprises one or a plurality of processor(s) 110 operatively connected to media drive 102 via media I/F 104 and to memory bank 115 via a system bus 108 . Memory bank 115 contains logical partitions (PLAR 1-n ) herein designated by reference numerals 112 , 114 , 116 and 118 . Although the partitions 112 - 118 are shown in FIG. 1 to reside outside processor 110 , those skilled in the art will recognize that a partition is a logical construct that includes the division of a computer system's processor(s), memory, and hardware resources into multiple units so that each unit can be operated independently from each other with its own operating system and applications. The number of logical partitions that can be created depends on the computer system's processor(s) model and resources available. Other elements (e.g. hardware resources, memory buses, I/O circuits, etc) of logically portioned computer system 100 will be readily apparent to those skilled in the art and are therefore omitted in this disclosure.
[0023] Each one of LPAR 1 through LPAR n , contains a virtual Ethernet adapter (VEA) designated by reference numerals 121 , 122 , 123 and 124 , respectively. LPARs 112 - 118 can communicate among themselves using VEAs 122 - 124 , via virtual network 125 , using LPAR management firmware 120 , such as IBM's Hypervisor. Persons of ordinary skill in the art will appreciate that although IBM's Hypervisor product is used here as an example of LPAR management firmware 120 , other partition management firmware products may be used. In addition, virtual Ethernet technology, which enables Internet Protocol (IP) based communication between logical partitions on the same computer system, is well known and detailed description thereof is omitted. Those interested in further details regarding virtual Ethernet technology may refer to, for example, the IEEE 802.1 Q standard, which describes virtual LAN (VLAN) technology.
[0024] LPARs 112 - 118 needing to access to an outside network may use a network interface (I/F) 130 , such as, e.g., an Ethernet switch. In order to communicate via network I/F 130 , LPARs 112 - 118 may use physical Ethernet adapters (PEA) which may be assigned to each logical partition, or may use a shared physical Ethernet adapter (SEA) located in any LPAR and connected to network I/F 130 . In the example illustrated in FIG. 1 , LPARs 112 - 118 may connect to an outside network using a shared PEA 134 via virtual networks 125 and 135 . Those skilled in the art may readily recognize the various virtual and/or physical topographies in which LPARs 112 - 118 may be connected to an outside network via network I/F 130 . Accordingly, the illustrative diagram of FIG. 1 is intended for exemplary purposes only.
[0025] Returning to FIG. 1 , processor 110 is shown to be operatively connected to a media drive 102 , which has access to computer-readable media 105 (hereafter simply referred to as “media 105 ”). Examples of computer readable media may include: nonvolatile, hard-coded type media such as Read Only Memories (ROMs) or Erasable, Electrically Programmable Read Only Memories (EEPROMs), recordable type media such as floppy disks, hard disk drives, CD-ROMs and DVD ROMs, and transmission type media such as digital and analog communication links, and wired or wireless communications links using transmission forms, such as, for example, radio frequency and light wave transmissions. The computer readable media may take the form of coded formats that are decoded for actual use in a particular data processing system.
[0026] In accordance with an exemplary embodiment, the depicted example of media 105 in FIG. 1 represents a version of media that has a ready to run version of NIM. In other words, media 105 may be encoded with the required NIM resources comprising, for example, a base SPOT, Ipp_source, at least basic VIO capabilities and any additional software needed for the installation/propagation of application images. Accordingly, in this particular embodiment, media 105 represents a network installer image that does not have to be installed as a NIM master (VIO server) into a dedicated LPAR to function. That is to say, a user may install/propagate application images across LPARs 112 - 118 directly from media 105 without having to configure a NIM master and/or VIO server. In addition, as it is more fully explained below, logically partitioned computer system 100 needs not have a predefined network in order to perform the installation/propagation of application images.
[0027] With reference now to FIG. 2 , a process 200 for propagating application images from computer readable media 105 onto each of a plurality of LPARs is illustrated. The process is described from the perspective of a user (e.g., systems manager, network administrator, or the like) initiating the installation/propagation of application images across LPARs 112 - 118 . For simplicity of describing, it is assumed that media 105 comprises all the necessary installation resources including, for example, a BOS boot image stored thereon, which may be utilized by the user to perform the various steps required for the installation. In addition, media 105 may be provided with a self-starting application “wizard” (e.g. an auto executing file) that would automatically launch and perform process 200 with minimal or not user intervention at all.
[0028] Process 200 starts when the user loads media 105 into media drive 102 of FIG. 1 . At step S 202 , logically portioned computer system 100 boots from media 105 . At step S 204 , instructions stored in media 105 cause processor 110 with the aide of firmware 120 to identify all available LPARs residing in LPAR terminal 100 , and determines whether an inter-LPAR network exists (S 206 ). If it is determined that an inter-LPAR network exists (YES at S 206 ), processor 110 identifies each LPAR in a conventional manner and stores any available identification (e.g. MAC address or VID) of each LPAR in memory (S 208 ). Alternatively, when no inter-LPAR network exists, the process advances (NO at S 206 ) forward to S 210 . At step S 210 , additional software resources in media 105 cause processor 110 to setup a temporary virtual network (e.g., temporary VLAN).
[0029] A temporary VLAN (represented in FIG. 1 by chain-link lines 128 ) may be configured utilizing currently known technology, such as the above-mentioned IEEE 802.1 Q standard in combination with suitable networking protocols, such as TCP/IP protocols. For example, if no inter-LPAR network has been predefined between LPARs 112 - 118 of FIG. 1 , VIO resources encoded in media 105 may automatically assign a virtual Ethernet adapter (VEA) to each existing LPAR. Then, by using virtual addressing and keeping the IP addresses to an internal subnet, such as, e.g., the 192.168.0.x address commonly used by D-HCP (Dynamic Host Configuration Protocol) routers, it is possible to temporarily assign a unique IP address known only internally to the CEC (central electronic complex) of computer system 100 . Alternatively, in the case that a inter-LPAR network may have been pre-established between LPARs 112 - 118 , software resources provided in media 105 may instruct processor 110 to setup an new and/or additional VLAN by assigning temporary MAC (Media Access Control) addresses to each one the VEAs 121 - 124 . Whether using virtual MAC addresses, virtual IP addresses, or a combination thereof, a temporary inter-LPAR network is created by connecting LPARs 112 - 118 to one anther for purposes of installation only. Thus avoiding conflicts with pre-established physical or virtual networks.
[0030] After a temporary virtual network has been established, the process advances to step S 208 . At step S 212 , software resources encoded in media 105 cause processor 110 to propagate (i.e. install) application images (e.g., BOS installs or mksysb, and any additional software necessary) to each one of LPARs 112 - 118 via the newly created VLAN. In the exemplary embodiment of FIG. 1 , VIO resources provided in media 105 in combination with firmware 120 may provide basic VLAN tagging for the dynamic routing of data packets to their respective destinations via the temporary virtual network 128 created at step S 210 . At step S 214 , process 200 ensures that all the desired LPAR units have been properly installed with the designated applications and advances forward (YES at S 214 ) to the next step. Alternatively, application image propagation is automatically repeated (NO at S 214 ) until all of the LPARs 112 - 118 residing in computer system 100 have been installed.
[0031] At step S 216 , after all installations have been performed, software resources encoded in media 105 instruct processor 110 to erase (e.g., deconfigure) temporary virtual networking resources. For example, the temporary virtual IP/MAC addresses assigned at step S 210 are now erased, and a new set of permanent physically addressable IP/MAC addresses are assigned to all or selected physical Ethernet adapters residing in any of LPARs 112 - 118 . In the embodiment of FIG. 1 , for example, a PEA 134 would be assigned an IP and/or MAC address that would be addressable from an outside network via network I/F 130 . In addition, VEAs 121 - 124 may be assigned permanent IP/AC addresses in order to connect to PEA 134 via a virtual network connection 135 . In the case that a virtual and/or physical network had been pre-established between LPARs 112 - 118 prior to the propagation of application images, the network information stored at step S 208 is restored to its original state. As a result, the process ends the propagation of application images with minimal user interaction and without the need of a pre-existing network.
[0032] It is contemplated that the exemplary method set forth above can be implemented in an automated manner, without the need for repeated user intervention and directly from removable storage media without having to define and install a NIM master and/or VIO server. Those skilled in the art will appreciate that many variations are possible within the scope of the examples described herein. Thus, while the features of the invention have been described with reference to particular examples, it will be understood that these and other changes may be made within the scope of the following claims. | A system and method for network image propagation without a predefined network advantageously allows customers to automatically perform several system BOS installation or mksysb restoration over a virtual network with no predefined network and minimal installer configuration overhead. A method for network image propagation comprises: identifying a plurality of logical partitions residing in the logically partitioned terminal; configuring a temporary virtual network to connect said plurality of logical partitions to each other, wherein each one of the logical partitions is assigned at least one of a virtual Internet Protocol (IP) address and a virtual Media Access Control (MAC) address; installing an application image on at least one of the logical partitions via the temporary virtual network; deconfiguring the temporary virtual network; and assigning at least one of a physical IP address and a physical MAC address to said at least one logical partition on which the application has been installed. | 6 |
CROSS REFERENCES TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a golf club head. More specifically, the present invention relates to a polymer face section of a golf club head to reduce energy losses when impacting a golf ball.
2. Description of the Related Art
Technical innovation in the material, construction and performance of golf clubs has resulted in a variety of new products. The advent of metals as a structural material has largely replaced natural wood for wood-type golf club heads, and is but one example of this technical innovation resulting in a major change in the golf industry. In conjunction with such major changes are smaller scale refinements to likewise achieve dramatic results in golf club performance. For example, the metals comprising the structural elements of a golf club head have distinct requirements according to location in the golf club head. A sole or bottom section of the golf club head should be capable of withstanding high frictional forces for contacting the ground. A crown or top section should be lightweight to maintain a low center of gravity. A front or face of the golf club head should exhibit high strength and durability to withstand repeated impact with a golf ball. While various metals and composites are known for use in the face, several problems arise from the use of traditional face structure and materials. In addition, material interaction of the golf club head and the golf ball during impact is an important factor for performance of the golf club. In addition, material interaction of the golf club head and the golf ball during impact is an important factor for performance of the golf club.
The golf ball is typically composed of a core-shell arrangement with a thin polymer shell, or cover material such as ionomers, surrounding a rubber-like core. These polymeric materials exhibit compression and shear, stiffness and strength properties dependent upon strain (load), input frequency (time dependency of small linear strain), strain rate (time rate of loading including large nonlinear strains), and temperature. The compression and shear stiffness properties of polymeric materials are measured and classified in terms of a storage moduli (E′, G′) and a loss moduli (E″, G″), respectively. The storage moduli (E′, G′) represents the amount of compression and shear energy, respectively, stored during a complete loading cycle. For quasi-static loading, it is equivalent to the well known Young's modulus (E′=E) and shear modulus (G′=G =E/(2(1+ν)), where (ν) is the material Poisson ratio. For most polymers, the storage modulus increases significantly with strain, input frequency, and strain rate. For example, typical storage moduli for golf balls at low speed impacts, in the temperature range (50-100° F.), are E′ ball =450-6000 lb/in 2 and G′ ball =150-2000 lb/in 2 . During high-speed impacts, in the temperature range (50-100° F.), the typical storage are E′ ball =9,000-50,000 lb/in 2 and G′ ball =3,000-16,500 lb/in 2 . The low speed impact represents a putting stroke or a soft pitch shot, while the high-speed impact represents a golf swing with an iron-type or a wood-type golf club head.
The loss moduli (E″, G″) represents the amount of compression and shear energy, respectively, dissipated during a cycle. For most polymers, the loss moduli also increase significantly with strain, input frequency, and strain rate, but the rate of increase can be very different than the aforementioned storage moduli. Finally, the magnitude of the loss moduli at a given strain, strain rate, frequency, or temperature typically vary from 0.005-2.0 times that of the storage moduli.
A loss (or damping) factor (η E , η G ) or loss angle (δ E , δ G ) for compression and shear are commonly defined as the ratio of the corresponding moduli; η E = Tan δ E = E ″ E ′ , η G = Tan δ G = G ″ G ′ .
These loss factors are an important measure of the damping capability (energy loss mechanisms) of the material. For most ball-type materials, (η E ≡η G ) and magnitudes fall in the range of 0.005 (low energy loss) to 2.0 (high-energy losses), where magnitudes clearly depend upon polymer composition, strain, input frequency, strain rate, and temperature. As a comparison, the loss factors (energy loss mechanisms) in a metallic face of a golf club head are on the order of 10-100 times smaller than that of a golf ball. For most elastomeric polymer materials operating below the glass transition region, the Poisson ratio is fairly constant with (ν=0.4-0.5), while for stiff polymers acting at or above the glass transition region (ν=0.3-0.33).
Thus, during impact of the golf ball with the golf club head a significant portion of impact energy is lost as a result of the large deformations (0.05 to 0.50 inches) and deformation rates of the high damped golf ball materials, as opposed to the small deformations of the low damped metallic club face (0.025 to 0.050 inches) materials. A larger portion of this impact energy is lost in the golf ball because the magnitude of the deformation, the deformation rate, and energy loss mechanisms is greater for the golf ball than the face of the golf club head.
Application of hard polymers to the face of the golf club head represents a traditional structure of natural wood golf club heads, where a hard insert material centrally located in the face of the golf club and requiring an exacting fit between two or more distinct elements. The hard insert must be manufactured to a close tolerance to fit within a recess in the face of the golf club, and high surface hardness is less efficient in transferring energy to the golf ball during impact with the golf club. A homogeneous face structure is simpler to manufacture but is limited to the inherent material properties of the single material comprising the face structure. The present invention achieves a more efficient energy transfer during impact while maintaining a simple construction.
BRIEF SUMMARY OF THE INVENTION
When a golf club head strikes a golf ball, large impact forces are produced that load the golf club head and the golf ball. Most of the energy is transferred from the golf club head to the golf ball; however, some energy is lost as a result of the impact. The present invention comprises an improved face structure for the golf club head to reduce impact energy losses, which could lead to greater efficiency in striking the golf ball. In a preferred embodiment the golf club head is a wood-type golf club head with a plurality of walls to define a hollow interior.
By allowing the golf club head to flex and “cradle” the golf ball during impact, the contact region as well as contact time between the golf ball and the face of the golf club head are increased, reducing the magnitude of the internal golf ball stresses as well as the rate of the stress build-up. This results in lower golf ball deformations and lower deformation rates to achieve lower energy losses in the golf ball during impact. The present invention accomplishes greater energy conserving impact by utilizing a specified polymer material layer on the face of the golf club head. During impact with the golf ball, the polymer layer compresses around the golf ball to enlarge the contact region and increase contact time of the golf ball, thus lowering the stresses and stress rate in the golf ball. Similarly, the polymer layer distributes the stresses to a backing structure in a more uniform manner. Also, the stress levels in the backing structure are significantly lower than the stresses of a similar metal golf club striking face without a polymer layer because there are no scorelines in the backing structure which serve to amplify the stresses. Thus the backing structure can be made thinner, and more flexible, than typical existing metal wood-type golf club heads. The more flexible backing structure coupled to the polymer layer can lead to even lower energy impact losses. The golf club head may be constructed from rigid material and still obtain the benefits of the present invention.
Coefficient of restitution (COR) is well known to those of ordinary skill in the art, and is defined as the ratio of the relative velocity of the golf ball to golf club head just after impact divided by the relative velocity of the golf head to golf ball just before impact. Expressed mathematically, the equation is outlined below: COR = V 2 - Ball - V 2 - Head V 1 - Head - V 1 - Ball
where V 2-Ball is the velocity of the golf ball measured immediately after impact with the golf club head; V 1-Ball is the velocity of the golf ball measured immediately before impact with the golf club head; V 1-Head is the velocity of the golf club head measured immediately before impact with the golf ball; V 2-Head is the velocity of the golf club head measured immediately after impact with the golf ball.
Polymer material chemistry and thickness determines important performance variables including durability, coefficient of restitution (COR) and material stress levels. In a preferred embodiment the polymer material should have a lower nominal (quasi-static) storage compression (E′) and storage shear (G′) moduli, lower nominal loss compression (E″) and loss shear (G″) moduli, and damping properties (η E , η G ) than these same properties of the golf ball E′ ball , G′ ball , E″ ball , G″ ball and (η E , η G ) ball respectively. Thus the polymer layer on the face of the golf club head will deform around, or “cradle”, the golf ball with lower energy loss mechanisms than the cover material of the golf ball. Since these polymer material storage and loss moduli significantly increase with golf club head impact speed, an important goal for the polymer material on the face of the golf club head is to have an effective lower storage compression and loss compression moduli (E′, E″) and storage shear and loss shear moduli (G′, G″) than the golf ball (E′ ball , G′ ball , E″ ball , G″ ball ) at the higher loading rates and input frequency found in the high speed impact associated with the wood-type golf club head. These loading rates are typically 1000-5000 in/in/sec and the input frequency is typically 500-4000 cycles/sec. Thus, polymer face materials that have higher storage and loss moduli than the golf ball at low load rates are also covered by the present invention, as long as the polymer face materials have lower effective storage and loss moduli than the golf ball at wood-type golf club head impact load rates. Ideally, the storage and loss moduli of the polymer face material would be lower than the golf ball properties and be strain, strain rate, and input frequency insensitive. Performance benefits can be obtained when the polymer face material has a storage and/or loss moduli limit of about twice the storage and/or loss moduli of the ball material. The polymer utilized in the face of the golf club head is much softer than a typical metallic face and the impact duration between the golf ball and the golf club head is increased.
One object of the present invention is to improve impact efficiency between a golf club head and the golf ball.
Another object is to incorporate a polymer material in the face section of a golf club head to perform as a compliant golf club face. Any number of rigid materials can be utilized in the manufacture of the golf club of the present invention to produce a compliant, or softer flexing performance, golf club face during impact with the golf ball.
A further object of the present invention is a wood-type golf club head having a polymer face material with a storage compression and storage shear modulus less than that of a golf ball at low loading rates.
Another object of the present invention is a wood-type golf club head having a polymer face material with a storage compression and storage shear modulus less than that of a golf ball at high loading rates.
Another object of the present invention is a wood-type golf club head having a polymer face material with a loss compression and loss shear modulus less than that of a golf ball at low loading rates.
Another object of the present invention is a wood-type golf club head having a polymer face material with a loss compression and storage shear modulus less than that of a golf ball at high loading rates.
Another object of the present invention is a wood-type golf club head having a polymer face material with a storage compression and storage shear modulus less than or equal to double the storage compression and storage shear moduli of a golf ball at low loading rates.
Another object of the present invention is a wood-type golf club head having a polymer face material with a storage compression and storage shear modulus less than or equal to double the storage compression and storage shear moduli of a golf ball at high loading rates.
Another object of the present invention is a wood-type golf club head having a polymer face material with a loss compression and loss shear modulus less than or equal to double the loss compression and loss shear moduli of a golf ball at low loading rates.
Another object of the present invention is a wood-type golf club head having a polymer face material with a loss compression and loss shear modulus less than or equal to double the loss compression and loss shear moduli of a golf ball at high loading rates.
Another object of the present invention is a wood-type golf club head having a face insert supported by a polymer material for flexing of the golf club face.
Another object of the present invention is to have a polymer face material composed of multiple polymer and/or metallic layers where the outer layers may be designed for improved durability and or spin-control.
Another object of the present invention is to have a nonhomogeneous polymer face material so that different material formulations may exist over the polymer face for the purpose of increasing impact velocity for center shots, but lower velocity or controlled spin for off-center shots.
Another object of the present invention is to have a golf club head with scorelines in a polymer face material.
Having briefly described the present invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a perspective view of a golf club head of an embodiment of the present invention.
FIG. 2A is a cross-sectional toe view along lines II—II of FIG. 1, illustrating a polymer material on a front section of the golf club head of an embodiment of the present invention.
FIG. 2B is a cross-sectional toe view of an iron-type golf club head, illustrating a polymer material on a front section of a golf club head of an embodiment of the present invention.
FIG. 3A is a cross-sectional toe view along lines II—II of FIG. 1, illustrating an alternative embodiment of the present invention with a front section of the golf club head having a face insert in conjunction with a polymer material.
FIG. 3B is a cross-sectional toe view along lines II—II of FIG. 1, illustrating an alternative embodiment of the present invention having a front section of the golf club head with a face insert in conjunction with a liquid media.
FIG. 3C is a cross-sectional toe view along lines II—II of FIG. 1, illustrating an alternative embodiment of the present invention having a front section of the golf club head with a face insert in conjunction with regions of a polymer material alternating with a liquid media.
FIG. 3D is a cross-sectional toe view along lines II—II of FIG. 1, illustrating an alternative embodiment of the present invention with a front section having a polymer material, a liquid media and a face insert.
FIG. 4 is a toe view of the golf club head during initial impact with the golf ball.
FIG. 5 is a graph of carry distance vs. golf club head speed for a standard product and the polymer face golf club of the present invention.
FIG. 6 is a graph of carry distance increase vs. golf club head speed for the polymer face golf club of the present invention.
FIG. 7 is a graph of total distance vs. golf club head speed for a standard product and a polymer face golf club of the present invention.
FIG. 8 is a graph of total distance increase vs. golf club head speed for the polymer face golf club of the present invention.
FIG. 9 is a graph of carry distance vs. shot location for a standard product and a polymer face golf club of the present invention.
FIG. 10 is a graph of total distance vs. shot location for a standard product and a polymer face golf club of the present invention.
FIG. 11 is a graph of impact efficiency vs. shot location for a standard product and a polymer face golf club of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Like numbers are used throughout the detailed description to designate corresponding parts of a golf club head of the present invention.
As shown in FIG. 1 a wood-type golf club head 10 comprises a face section 12 , a plurality of scorelines 13 , a rear section 14 , a top section 16 , a bottom section 18 , a toe section 20 , a heel section 22 , a center section 23 and a hosel inlet 24 to accept a golf shaft (not shown). The golf club head 10 is a unitary structure which may be composed of two or more elements joined together to form the golf club head 10 . Structural material for the golf club head 10 can be selected from metals and non-metals, with metals such as stainless steel and titanium being preferred embodiments. The face section 12 contains an impact surface for contacting a golf ball 32 (not shown).
FIG. 2A is an embodiment of the present invention where the face section 12 of the golf club head 10 contains a polymer 26 covering a backing structure 28 . FIG. 2B is an iron-type golf club head of an embodiment of the present invention. In a preferred embodiment, the polymer 26 has material storage compression and loss compression moduli (E′, E″) and storage shear and loss shear moduli (G′, G″) properties lower than the golf ball material properties (E ′ ball , G′ ball , E″ ball , G″ ball ) at either low or high impact speeds. Low impact speeds are defined as the polymer 26 having a strain rate of less than 0.1 in/in/sec. High impact speeds are defined as the polymer 26 having a strain rate of less than 1000/in/in/sec. The E′ E″, G′ and G″ are measurements that quantify the dynamic performance properties of the polymer 26 , and such measurement techniques are well-known in the art.
Materials for the polymer 26 include ionomers, polyamines, polyamides, polyetheramides, nylons, fluoroelastomers, polyurethanes, and butadiene rubbers. A preferred embodiment is a thermosetting or thermoplastic polyurethane. A preferred polyurethane is formed from the reaction of a para-phenylene diisocyanate (“PPDI”) prepolymer with a curing agent. The PPDI prepolymer is formed by a reaction of PPDI with an ester polyol, a polyether polyol or a blend of more than one of these compounds. A preferred ester polyol compound is polycaprolactone. The PPDI prepolymer is then cured with an agent for a set period of time. The agent may be a diol (e.g. 1,4 butane diol, trimethylpropanol, etc.), a mixture of diols (e.g. 1,4 butane diol and ethylene glycol, or other suitable glycols), a hydroquinone, a mixture of hydroquinones, a triol, a mixture of triols, a diamine, a mixture of diamines, an oligomeric diamine, or a blend of some or all of these materials. The polyurethane may be either thermosetting or thermoplastic. The PPDI polymer is described in detail in co-pending patent application Ser. No. 09/295,635 entitled “Golf Ball with Polyurethane Cover”, which has been assigned to the assignee of the present invention, and which is hereby incorporated by reference as if fully set forth herein. However, the present invention is not limited to the formulations disclosed in this co-pending application.
The polymer 26 forms the compliant surface on the golf club head 10 for impacting the golf ball 32 . In other words, a relatively soft material, such as the polymer 26 , can provide a more efficient energy transfer to the golf ball 32 by reducing the magnitude of the internal stress and the rate of build-up of that stress in the golf ball 32 . A thickness “D” for the polymer 26 is not particularly limiting, and may range between 0.001 and 0.5 inches in addition to varying in depth across the face section 12 . The polymer 26 may include the scorelines 13 on the face section 12 . In addition, the face section 12 may be composed of multiple layers of polymers and/or metallics to improve durability and/or control spin of the golf ball 32 . In an alternative embodiment, the face section 12 may be nonhomogeneous so that the polymer 26 formulation varies over the face section 12 to produce different levels of energy loss or spin control for different hit locations.
FIG. 3A is an alternative embodiment of the present invention where an insert 30 is used in conjunction with the polymer 26 to provide a compliant face. In a preferred embodiment the polymer 26 has material storage compression and loss compression moduli (E′, E″) and storage shear and loss shear moduli (G′, G″) properties lower than the golf ball 32 material properties (E′ ball , G′ ball , E″ ball , G″ ball ) at either low or high impact speeds. The insert 30 can be a metal or a non-metal material. The polymer 26 material may include scorelines 13 on the face section 12 , be nonhomogeneous and alternatively composed of multiple layers.
FIG. 3B is an alternative embodiment of the present invention where the insert 30 covers a liquid media 27 in the face section 12 of the golf club head 10 . The liquid media 27 is an aqueous or non-aqueous liquid to help approximate polymer properties of low storage and loss moduli characteristics. Among the possible choices for the aqueous compositions for the liquid media 27 are: water, saline solution, starch solution or sugar solution; while possible choices for the non-aqueous compositions are low molecular weight oils and high molecular weight oils. FIGS. 3C and 3D represent possible choices for combining the polymer 26 material with the liquid media 27 , arranged as alternating regions as in FIG. 3C or encapsulated region as in FIG. 3 D.
FIG. 4 represents an initial impact where the polymer 26 is compressed by the golf ball 32 . Rebound characteristics of the polymer 26 determine the COR up to a material compression defined limit, after which the combined deflection of the backing structure 28 and the polymer 26 dictates COR values.
FIG. 5 is a graph of carry distance, also referred to as flight distance, of the golf ball after impact vs. speed of the golf club head during golf ball impact for a 9° Callaway Golf® Biggest Big Bertha® (hereinafter BBB) driver. Carry distance refers to the linear distance over the ground traversed by the airborne golf ball, and is well known by those of ordinary skill in the art. In this instance, polymer 26 is a para-phenylene diisocyanate having a uniform thickness (“D” in FIG. 2 a ) of 0.125 inches which covers the backing structure 28 with a thickness of 0.100 inches (a standard BBB has a face section 12 with a thickness of 0.135 inches). Because the weight combination of the polymer 26 and the backing structure 28 is less than the standard BBB, 8 grams of lead tape were added to the club head 10 to match the weight of the standard BBB.
A line 34 illustrates the linear relationship between carry distance and speed of the club head for impact speeds of 80, 90, 100 and 110 miles per hour (mph), designated 36 , 38 , 40 and 42 respectively. By comparison, line 44 illustrates the same BBB driver containing the polymer 26 on the face section 12 , with impact speeds of 90 and 100 mph, designated 46 and 48 respectively. Increased carry distance resulting from the use of the golf club head 10 of the present invention is more dramatic at the slower head speed of 46 than that of 48.
This speed dependent improvement is better illustrated in FIG. 6 where an increase (delta) in carry distance resulting from use of the golf club head 10 of the present invention is plotted vs. head speed of the golf club head. Note line 50 decreases with increasing head speed, carry distance at 90 mph is approximately double the carry distance at 100 mph, points 52 and 54 respectively.
FIG. 7 represents total linear distance traveled by the golf ball while FIG. 8 plots the increase in total distance for the golf club head 10 containing the polymer 26 of the present invention. The total distance of FIGS. 7 and 8 includes the carry distance of the golf ball, as explained earlier, and distance the golf ball travels on the ground between ground contact and final resting position, and is well known by those of ordinary skill in the art. Graphical results of FIGS. 7 and 8 closely resemble FIGS. 5 and 6 although ground and turf conditions can have a large impact on the post airborne portion of total distance.
FIGS. 9 and 10 represent carry and total distance, respectively, for a 10° BBB driver at 90 mph head impact speed for the heel section 22 , the center section 23 and the toe section 20 hit locations on the face section 12 . Note that the heel, center and toe section hit locations, 22 , 23 and 20 respectively, exhibit an increased carry distance for the golf club head 10 of the present invention. The center section 20 hit location, at 100 mph club head speed, likewise exhibit an advantage in carry distance for the golf club head 10 of the present invention.
FIG. 11 is a graph of impact efficiency of the golf club head with the golf ball vs. impact location on the golf club head for a 10° BBB driver. Impact efficiency (ε) is a truncated version of the COR equation cited earlier, where (ε) is expressed mathematically as: ɛ = V 2 ball V 1 club head
where V 2 ball is the velocity of the golf ball measured immediately after impact with the golf club head and V 1 club head is the velocity of the golf club head measured immediately before impact with the golf ball. Trace 56 represents impact efficiency of a standard BBB at 90 mph with a Titleist® Tour Balata golf ball when impact occurs in the heel section 22 , the center section 23 and the toe section 20 of the face section 12 . Trace 60 represents the same BBB containing the polymer 26 of the present invention with increased efficiency for the heel, center and toe section, 22 , 23 and 20 respectively, hit locations. Trace 58 represents impact efficiency of a standard BBB at 90 mph with a Wilson® Distance golf ball when impact occurs in the heel section 22 , the center section 23 and the toe section 20 of the face section 12 . Trace 62 represents the same BBB containing the polymer 26 of the present invention with an increased efficiency for the heel, center and toe section, 22 , 23 and 20 respectively, hit locations. Arrow 64 represents magnitude of efficiency increase of the golf club head 10 of the present invention for the heel section 22 hit location using a Titleist® Tour Balata golf ball; while arrow 66 represents magnitude of efficiency increase of the golf club head 10 of the present invention for the heel section 22 hit location using a Wilson® Distance golf ball. Similar efficiency increases are observed for the center section 23 and the toe section 20 hit locations. Note that efficiency is dependent upon club head impact speed, and decreases for both standard and polymer coated golf club heads at 100 mph but still maintains an efficiency advantage for the golf club head 10 of the present invention.
The polymer 26 can be manufactured separately from the golf club head 10 and attached using adhesives and/or mechanical fasteners. Other alternatives include casting, molding or spraying the polymer 26 onto new or existing golf club heads.
From the foregoing it is believed that those skilled in the pertinent art will recognize the meritorious advancement of this invention and will readily understand that while the present invention has been described in association with a preferred embodiment thereof, and other embodiments illustrated in the accompanying drawings, numerous changes, modifications and substitutions of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing except as may appear in the following appended claims. Therefore, the embodiments of the invention in which an exclusive property or privilege is claimed are defined in the following appended claims. | A golf club head having a face section with a polymer surface can provide a more efficient impact between a golf ball and the golf club head. By utilizing a polymer surface with desired material properties of stress, strain and damping levels, the face section will incur higher strain and strain rate levels than the golf ball. These lower internal stresses within the golf ball yield a more efficient impact with a golf club head. | 2 |
This is a Continuation prior application Ser. No. 09/697,931 filed Oct. 26, 2000, now U.S. Pat. No. 6,520,260 for “WELL TREATMENT TOOL AND METHOD OF TREATING A WELL” which claims the benefit of U.S. Provisional Application Serial No. 60/161,859, filed Oct. 27, 1999.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to tools and equipment used in the oil, gas, and water well industry, and more specifically to a treatment tool which secures in line along the pump actuation or “sucker” rod string in a completed well hole. The treatment tool provides for the distribution and pressure regulation of a solvent or other fluid, which is pumped into the hole through the sucker rod for distribution into the production tube or pipe string. The device may be used to provide a continuous supply of solvent or other fluid to the oil or other fluid being pumped or delivered from the well, while the well remains in continuous operation.
2. Description of the Prior Art
Wells drilled in the ground for the drawing of subterranean fluid substances often encounter various problems with undesirable foreign matter which at least partially blocks the production tube or pipe string of the finished well and obstructs the pumping or flow of the fluid from the well. When this occurs, additional time and expense is encountered as the foreign material is removed from the well and fluid flow resumes.
This is particularly true in the oil industry, where subterranean crude oil deposits generally have less desirable substances mixed therein. One of these substances is called paraffin, a hydrocarbon which hardens to form a wax-like material as it cools. While the crude oil is universally quite warm or even hot at a depth from a few thousand to several thousand feet beneath the surface, it tends to cool as it rises up the production tube string of a producing well. When the paraffin rises to a depth where the ambient temperature is around 160 degrees Fahrenheit, it begins to solidify and adhere to the walls of the production tube string. The problem becomes worse with decreasing temperatures nearer the surface.
The solidifying paraffin will eventually block the oil flow from below, and require treatment of the production string in order to remove the paraffin buildup. This is conventionally done by mechanical means, electrical heating, hot water, and/or solvents introduced into the well. However, the various means of removing the paraffin from the production string generally require that flow from the well (either pumped or free flowing) be stopped while the treatment means is introduced into the well, and the well is treated. For example, chemical treatment using solvents is quite commonly used to remove paraffin buildup, but the chemicals are conventionally forced down the production string, in the opposite direction of pumped or natural flow. Obviously, oil cannot be recovered from the well during the time the chemical is being introduced into the well.
However, even if the paraffin buildup is removed from the production string, paraffin buildup may still occur in the oil processing and storage system after it leaves the well. Anywhere the temperature drops below the critical level of about 160 degrees Fahrenheit, paraffin will begin to harden in the system. Typically, oil leaves the well head to a tank battery, or series of storage tanks. The oil is then processed to remove water and gas mixed therewith, by heating in a heater treater. Paraffin makes it difficult to separate water from the oil, thus requiring additional heat (generally in the form of gas separated from the oil) to produce the desired reaction. Moreover, even if the paraffin is heated to melting in the heater treater, it will still solidify in valves, pipelines, and storage tanks prior to reaching the heater.
Accordingly, a need will be seen for a means of treating a producing well to remove foreign substances therefrom on a continuous basis, without interrupting the output of the well. The foreign substance removal means is particularly needed in the case of wells for oil with paraffin mixed therewith, to dissolve the paraffin and keep it in solution in the oil from a point in the well below the temperature at which it begins to solidify, and throughout the entire pipe and tank system of the oil field. While the present invention is particularly well suited for use in the oil production industry, it may also be adapted for use with other types of subterranean wells. A discussion of the related art of which the inventor is aware, and its differences and distinctions from the present invention, is provided below.
U.S. Pat. No. 4,011,906 issued on Mar. 15, 1977 to Harvey C. Alexander et al. describes a Downhole Valve For Paraffin Control, comprising a non-concentric (axially offset) valve which is assembled as a “sub” or short length of the production tube string. Solvent is forced down the production string to the valve, where a ball check valve is forced from its normally closed position by the pressure of the solvent, to allow the solvent to flow outwardly from the production string to the space between the production string and casing. It will be seen that the forcing of the solvent downwardly through the production string, which is normally used to deliver oil to the surface, requires that the well be shut down during the time that the solvent is being forced into the well. The present valve tool, adapted for inclusion as a “sub” in the sucker rod of the well, allows oil (or other substance being delivered by the well) to continue to flow upwardly through the production tube string without interruption, during treatment of the well. The solvent is carried up through the production tube with the flow of fluid being delivered from the bottom of the well, to flush paraffin or other substances from the production string.
U.S. Pat. No. 4,224,993 issued on Sep. 30, 1980 to Leonard Huckaby describes a Dewaxing Valve For Use In Oil Wells, comprising a valve mounted externally to the production tube, between the production string and the outer casing of the downhole. While the valve mechanism is somewhat different than that of the Alexander et al. valve discussed above, the operation is similar, with the well being shut down during the treatment process.
U.S. Pat. No. 4,279,306 issued on Jul. 21, 1981 to Robert D. Weitz describes a Well Washing Tool And Method, comprising a plurality of resilient packings on a “sub” which secures in line with the production tube string of the well. Pressure causes the central sleeves of the device to extend, thereby compressing the packings against the inner walls of the well casing. Sealing the device against the well casing routes the washing fluid through the perforated casing to wash any loose material away which may surround the outer casing. The fluid returns to the annulus between the casing and production tubing by perforations in the casing above the tool. Again, the well cannot produce oil or other fluid during use of the Weitz tool, as fluid under pressure is being forced downwardly through the production tube string, unlike the present invention where downward fluid flow is only through the hollow sucker rod.
U.S. Pat. No. 4,681,167 issued on Jul. 21, 1987 to Paul B. Soderberg describes an Apparatus And Method For Automatically And Periodically Introducing A Fluid Into A Producing Oil Well. The apparatus includes a valve placed in the downhole, which valve is actuated by pressure and/or movement of the sucker rod therethrough. The valve essentially fills the inside of the production tube string, with actuation either blocking or opening the valve to prevent or allow fluid to flow through the production string. The device operates generally in the manner described above for the other systems of the related art, in that fluid must be pumped downwardly through the production string from time to time in order to flush paraffin or other substances from the production tube string. This of course requires that fluid production from the well be stopped during the time that solvents or other fluids are being forced down the production tube string. While Soderberg states that “Present methods for removing such deposits employ hot oil, water or steam which is generally forced down the annulus between the production string and borehole casing” (column 1, lines 44-47), none of the related art discussed above, including Soderberg, do so. Rather, they force the fluid down the production tube string, rather than down the annulus between the production string and casing or wall of the downhole.
U.S. Pat. No. 4,995,462 issued on Feb. 26, 1991 to David Sask et al. describes a Dewaxing Control Apparatus For Oil Well, comprising a housing installed in line with the production tubing, as in the case of other devices discussed above. Dewaxing solvent or the like is pumped down the annulus between the well casing or wall and the production tubing, with the device blocking further downward flow therepast. The solvent then enters the interior of the production tube string by means of passages through the device, and is flushed back to the surface by means of the upward flow of oil through the interior of the production tube string. This is the only art of that discussed above, which causes the solvent to flow upwardly through the production string, in the manner of the present invention. However, Sask et al. still do not pump the fluid downwardly through the hollow sucker rod, or provide a valve which is installed in the sucker rod rather than the production tube string, as in the present invention. If the Sask et al. valve required removal from the hole, the production tube string would have to be lifted and disassembled at least to the depth of the valve. Such production tube removal would of course also require the removal of the entire sucker rod string before removal of the production tube string could take place. In the present invention, only the sucker rod string would have to be removed from the hole, with the production tube string remaining in place in the hole.
U.S. Pat. No. 5,056,599 issued on Oct. 15, 1991 to Walter B. Comeaux et al. describes a Method For Treatment Of Wells, comprising a telescoping valve which is axially offset from the production tube string, in a configuration somewhat similar to the device of the patent to Huckaby described further above. Comeaux et al. provide an initial balancing pressure in their valve by means of a compressed nitrogen charge, which holds the valve in a closed position until a superior pressure in the well downhole pushes the valve open. The Comeaux valve depends upon pneumatic means and differential pressure for operation, unlike the present well treatment tool, and also requires that production flow from the well be interrupted for the treatment fluid (hot water, solvent, etc.) to be introduced down the production tube string, where the Comeaux et al. valve routes it into the well casing. The present valve routes the solvent down the hollow interior of the sucker rod, where the valve is disposed, and routes the fluid outwardly from the sucker rod into the production tube interior.
U.S. Pat. No. 5,282,263 issued on Jan. 25, 1994 to John E. Nenniger describes a Method Of Stimulating Oil Wells By Pumped Solvent Heated In Situ To Reduce Wax Obstructions. The apparatus used in the method is an electrical resistance heater which is lowered to the bottom of the production tube string of the well. Solvent is then introduced into the well via the production tube string, and heated by the heater. As in all but one of the prior art devices discussed above, production must be stopped when the Nenniger method and apparatus is used in order for the solvent to be pumped into the well, downwardly through the production tube string. Moreover, the Nenniger apparatus and method circulates the solvent outwardly through the conventional passages in the lower end of the production tube string and casing, and into the surrounding geological structure. The Nenniger heater element also precludes the installation of a pump in the well, as it seals against the pump seating nipple at the bottom of the production tube string and takes the position of the pump. Thus, production must be suspended in a pumping well, with the pump and sucker rod removed for installation of the Nenniger apparatus.
PCT Patent Publication W092/06274 published on Apr. 16, 1992 to John E. Nenniger describes a Method And Apparatus For Well Stimulation. This patent publication corresponds to the U.S. patent to the same inventor, described immediately above, with the same differences and distinctions being noted.
U.S. Pat. No. 5,924,490 issued on Jul. 20, 1999 to Stone is directed to a well treatment tool which includes a generally cylindrical body installed in a sucker rod string. The body includes an upper end which has an axial fluid flow entrance passage which accepts treatment fluid from the sucker rod string, but which is plugged at the opposite end. A ball and seat valve assembly is provided which checks the flow of fluid between the hollow sucker rod string and the fluid flow passage way defined between the sucker rod string and the production tubing.
None of the above inventions and patents, either singly or in combination, is seen to describe the instant invention as claimed.
SUMMARY OF THE INVENTION
The present invention comprises a well treatment tool for introducing a solvent fluid or the like to a subterranean well. The tool is particularly adapted for use in removing solidified paraffin buildup from the inner wall of the production tube string of an oil well, but may be used in other well types and treatments as well. The present tool installs concentrically in line in the “sucker rod,” or pump actuating rod string, of a well, and receives solvent or other treatment fluid through the hollow core of the sucker rod. A valve, is provided to preclude unwanted or excessive flow of solvent fluid through the device until a predetermined solvent pressure has been reached, which pressure is controllable from above ground. When adequate pressure is achieved to open the valve, the solvent or other fluid flows from the interior of the hollow sucker rod, outwardly through the tool, and into the interior of the surrounding production tube string, where it is carried upwardly back to the surface along with fluid being pumped or otherwise delivered from the well.
The present well treatment tool is capable of treating a well at any depth, from the very bottom of the well adjacent the pump, to any intermediate depth. The tool may be installed at any point desired along the sucker rod, as a “sub,” or shorter unit of the rod string. Preferably, the tool is installed a few hundred feet below the point at which paraffin begins to solidify in the production tube string of an oil well, in order to be flushed upwardly with the oil to dissolve the paraffin buildup thereabove.
It will be seen that the present tool is capable of treating a well from the problem area below ground, through the entire above ground pipeline, initial treatment, and on site storage system. The solvent delivered by the present tool is disseminated from the tool upwardly throughout the downhole production tube, due to the oil being pumped or otherwise delivered from the bottom of the hole. The oil, with the solvent carried therein, continues to keep paraffin in solution throughout its travel through the above ground initial processing and storage tank system.
It will be noted that the present tool is not limited to use with a pumping type well, but may also be used with a flowing or artesian well. The tool may be lowered down the production tube at the end of a sucker rod string, to the depth desired, without connecting the sucker rod string to other components (e. g., pump) therebelow.
Accordingly, it is a principal object of the invention to provide an improved well treatment tool for installing concentrically in line with the sucker rod string of a production subterranean fluid well.
It is another object of the invention to provide an improved well treatment tool which accepts treatment fluid from the hollow core of the sucker rod string, and distributes the fluid into the interior of the surrounding production tube string.
It is a further object of the invention to provide an improved well treatment tool which includes valve means precluding backflow of fluid from the well through the tool.
An additional object of the invention is to provide an improved well treatment tool which is adapted for simultaneous treatment of fluid being delivered from the well during the time the well is producing, without requiring shutdown of the well.
Yet another object of the invention is to provide an improved well treatment tool which is adapted to treat fluid being delivered from the well, from the location of the tool in the well downhole throughout the above ground initial treatment and storage system.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become apparent upon review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of the preferred embodiment when read in conjunction with the accompanying drawings, wherein:
FIG. 1 is an environmental elevation view in section of the present well treatment tool, showing its features and operation.
FIG. 2 is an environmental view in section of a pumping well with the present treatment tool installed therein.
FIG. 3 is an environmental view in section of a pressure well with the present treatment tool installed therein.
FIG. 4A is a view of a perforated sub-coupling device.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE INVENTION
The present invention comprises various embodiments of a well treatment tool, indicated by the reference numeral 10 in FIGS. 1, 2 and 3 . The tool 10 is used to deliver a well treatment fluid, such as a solvent indicated by the arrows S of FIG. 1, into the production fluid flow (e. g., oil, indicated by the arrows O of FIG. 1) into the production tube string P.
As discussed in the introduction to the Description of the Related Art, fluids delivered from subterranean wells of various types often have various contaminants or impurities therein, which can contaminate the well and/or above ground initial processing and storage systems in some way or another. An example of this is the oil industry, where subterranean crude oil often includes some fraction of paraffin therein. While the subterranean crude oil is generally sufficiently far beneath the surface that the temperature is relatively high, perhaps two hundred degrees Fahrenheit or more, it will cool as it travels up the production tube string P of the well. Paraffin, normally in solution in the crude oil, will begin to precipitate out of solution as it reaches an elevation at or below the melting point of the substance, approximately 160 degrees Fahrenheit (depending upon the specific molecular weight and structure of the paraffin material. As it solidifies, it condenses on the relatively cooler inner walls I of the production tube string P. This paraffin buildup results in a reduction in cross sectional area within the production tube string, which reduces the oil flow within the string and thus the production of the well.
The tool 10 of FIG. 1 has a generally cylindrical body 12 , with an internally threaded upper or first end 14 and an opposite internally threaded lower or second end 16 . The threads of the two ends 14 and 16 are configured to mate with the cooperating internal threads of a hollow sucker rod R 1 (shown schematically), concentrically connected to the upper end 14 of the tool 10 are coupled to sucker rod R 2 . The tool may have pin or box connections on either end or any combination of pin and box connections.
The sucker rod string portions R 1 and R 2 are generally hollow, with a concentric passage A formed therein. Normally, no fluid is passing through or resident in the passages A; the rods R 1 and R 2 are hollow in order to reduce the weight of the sucker rod string, which can be considerable in a sucker rod assembly having a length of several thousand feet. However, the central passage A of the hollow sucker rod R 1 provides for the delivery of a fluid, such as the solvent S, therethrough to the present well treatment tool 10 . The tool 10 includes an axial passage 18 in the upper end 14 thereof, which communicates with and accepts the fluid or solvent S from the upper sucker rod passage A. A normally closed valve, is installed within the tool body 12 to control the flow of fluid of outward into the wellbore.
It will be recognized that the fluid (oil O, etc.) at some great depth in the well is at an extremely high pressure, with the well fluid O naturally tending to flow from the high pressure area within the production tube string P to the lower pressure area within the interior passage A of the sucker rod R 1 (assuming no back pressure of treatment fluid S exists within the interior passage A). Accordingly, a spring 22 is provided to hold the valve 20 against seat 21 in a normally closed position. The spring 22 may be calibrated to provide a predetermined pressure to hold the valve 20 closed, depending upon the depth at which the tool 10 is to be installed. Various calibration means (not shown), such as a separate threaded screw adjustment, shims or washers beneath the spring 22 , etc., may be provided to adjust the spring 22 pressure, as desired.
When treatment fluid S is applied through the sucker rod passage A at sufficient pressure, it forces the valve 20 away from seat 21 to open against the spring 22 to allow flow of fluid S downwardly through the valve and out of the tool body 12 , by means of one or more radial fluid distribution passages 18 and into the production fluid passage F defined between the inner wall I of the production tube string P and the body 12 of the tool 10 . (The inner diameter D of the production tube string P is considerably more than the diameter of the tool 10 , with the difference in the tool diameter 30 and production tube internal diameter D defining the production fluid passage F therebetween.) As the lower end 16 of the tool 10 is solid, the treatment fluid S cannot flow downwardly into the lower sucker rod R 2 .
As is shown in the view of FIG. 1, valve 20 includes a generally cylindrical movable valve member 51 which is biased upward by spring 22 and which resides within cylindrical cavity 53 formed within the tool body 12 . A plurality of sliding interface seals 56 may be provided on the exterior surface of cylindrical body 51 . Preferably, these seals comprise O-ring seals which are located within O-ring seal grooves (not visible in the view of FIG. 1) which are formed circumferentially in the exterior surface of cylindrical valve body 51 . The uppermost end of valve body 51 is contoured to define a raised seat portion 55 which is biased by spring 22 into sealing engagement with valve seat 21 which is carried in the upper portion 14 of tool 10 . The contour of valve seat 24 and raised seat portion 55 should provide for good sealing engagement.
FIGS. 2 and 3 disclose two different types of wells which might use the present tool 10 or any alternative embodiment. In FIG. 2, a pumping type well W 1 is shown, with a downhole pump U installed in the bottom of the well W 1 . A sucker rod string, comprising an upper sucker rod portion R 1 and a lower sucker rod portion R 2 , is installed generally concentrically down the production tube string P to actuate the pump U. The upper end of the string is alternately lifted by a well pump walking beam apparatus B, to cycle the pump U in the bottom of the well W 1 . Fluid pumped upwardly from the well W 1 through the production tube string P exits the well at the wellhead H, where it is initially treated to separate water and gas therefrom and thence passed via delivery lines and control valves L to a battery of storage tanks T. All of the above described components are conventional.
However, a well treatment tool 10 is installed as a “sub,” or shorter than standard length of sucker rod, between the upper and lower sucker rod string portions R 1 and R 2 , at some predetermined depth in the well W 1 . In an oil and/or gas well, this depth is determined by the temperature in the well downhole, and is at a point where the temperature is at or slightly above the melting point of any paraffin issuing from the well. A point approximately three hundred feet below the paraffin solidification point has been found to be suitable. A treatment fluid storage tank 32 is provided at the surface, with a treatment fluid line 34 extending to a treatment fluid pump 36 . (The pump 36 is shown at the walking beam B, but may be located at any practicable position, as desired.)
From the pump 36 the fluid is routed through a flexible high pressure line 38 (e.g., high pressure hydraulic hose, etc.) to accommodate the movement of the head of the walking beam apparatus. The line 38 is joined to the upper end of the sucker rod string at a connector 40 . The treatment fluid or solvent is thus pumped downwardly into the downhole of the well W 1 , through the hollow core of the sucker rod R 1 , until it reaches the well treatment tool 10 . The pump 36 pressure is increased to exceed the preset opening pressure of the valve spring 22 of the tool 10 , whereupon the well treatment fluid is injected through the axial fluid entrance passage 18 , past the valve 20 , and outwardly through the radially disposed passage(s) 28 of the tool 10 into the production fluid passage F defined between the tool 10 and the production tube string P.
As the production fluid (oil, etc.) is carried upward through the production fluid passage F by the action of the downhole pump U, it will carry the well treatment fluid upwardly with it to flush or wash contaminants (e. g., paraffin buildup) from the internal walls of the production tube string P. Thus, the treatment fluid or solvent does not travel farther downwardly in the downhole of the well, where it might be lost between the production tube string and the outer downhole casing or sleeve, or perhaps be dissipated into the fluid or oil bearing strata at the bottom of the downhole. The present well treatment tool 10 ensures that all of the treatment fluid or solvent will be delivered only to those points and locations where it is needed.
Once the production fluid, with the well treatment fluid mixed therewith, leaves the wellhead H, it may be distributed to an initial treatment area, such as a heater treater (not shown), where the substance, e.g., crude oil, is heated to separate water and gas therefrom. The crude oil or other fluid is then placed in storage tanks T of a tank battery. With the solvent fluid being mixed with the crude oil throughout the initial processing and storage steps, it will be seen that any paraffin will remain dissolved in a liquid state within the oil, even when the oil cools in the storage tank battery. Thus, the present invention serves to preclude the formation of paraffin solids not only in the well downhole, but throughout the above ground treatment and storage system.
The tool 10 may be installed in the sucker rod string by means of the externally or internally threaded ends, and a suitable coupling C, with an exemplary coupling depicted in FIG. 4 A. Tools of the present invention may be fabricated having one internally threaded end and an opposite externally threaded end to eliminate the need for a coupling.
FIG. 3 discloses a tool 10 installation in a flowing or artesian well W 2 , where subterranean pressure is sufficient to deliver the production fluid from the well without need for any pump means. Such wells W 2 are generally capped, and may have a lubricator E installed at the wellhead, as shown schematically in FIG. 3 . In such flowing wells W 2 , no pump is required at the bottom of the well, but a chemical pump is required at the surface. This precludes any requirement for a sucker rod string installation in the production tube string P, but a partial sucker rod string R 3 is installed through the lubricator E in order to suspend a well treatment tool, e. g., tool 10 , at a predetermined depth within the well W 2 . As no pump is installed at the bottom of the downhole, no lower sucker rod string portion need extend below the tool 10 within the production tube string P.
Operation of the tool 10 is essentially the same as that described above for the tool 10 of the pumping well W 1 of FIG. 2 . Treatment fluid is delivered from a storage tank 32 a to a treatment fluid pump 36 a via a delivery line 34 a , and thence to the upper sucker rod string R 3 by means of a high pressure line 38 a . Treatment fluid travels downwardly through the upper sucker rod string R 3 , until it reaches the tool 10 installed at the lower end thereof. The fluid then passes through the internal valve mechanism of the tool when sufficient pressure is provided by the treatment fluid pump 36 a at the surface, to be distributed from the tool into the production fluid.
The treatment fluid or solvent then mixes with the production fluid in the fluid passage F between the tool 10 and the surrounding production tube string P, as in the case of the pumped well W 1 . Delivery of the mixed production and treatment fluids to the surface for further processing and storage is essentially identical to that described above for the pumped well W 1 , with the fluid mixture being delivered to an initial treatment area (not shown) and thence to a battery of storage tanks T via delivery lines and valves L. The mixture of paraffin solvent with crude oil serves to preclude the paraffin from settling out of solution with the oil as it cools in the storage tanks, thus obviating any periodic need to clean out the paraffin buildup in the bottoms of the storage tanks T.
The tension of the spring is set in a predetermined amount which in-part controls the flow of treatment fluid. The tension must be large enough to maintain the valve in a closed position most of the time. Only under certain pressure conditions is the valve opened. One factor is the “back pressure” on the well, which is established by the equipment settings at the surface on the back pressure valve. One other factor is the amount of pressure supplied to the column of treating fluid by the chemical pump which is also located at the surface.
Ignoring these factors (back pressure and pump pressure), the spring must provide enough force to keep the valve closed during most portions of the chemical pump cycle. For example, in a situation in which the tool is going to be located at 2,200 feet, and in which the sucker rod string is ⅜ of an inch in diameter, a column of Xylene treating fluid, for example, will weigh approximately A pounds. Of course, additional force is generated due to the pumping action which move the sucker rod string a known distance, but this force is typically about 10-20% of A pounds ordinarily. Therefore, the force of the spring is set for the valve in the range of approximately A+Y pounds to A+X pounds, and will accordingly open at a pressure amount somewhere in that range.
In the preferred embodiment, the valve will generate a full one-half inch opening. Fluid will pass out and mix with the wellbore fluids. In the preferred embodiment a well may need about two gallons of Xylene per day, so the tool should delivering less than one-half quart per hour.
If the back pressure value is set to a particular value a higher force setting will be required for the spring.
In summary, the present well treatment tool 10 will be seen to provide a much needed means of providing simultaneous treatment for a producing well, without need to shut down well production for treatment. The present tool 10 may be operated continuously, if needed, but treatment may be provided on an intermittent basis as required or desired, merely by operating the treatment fluid pump at the surface accordingly. The present well treatment tool and system could be configured to operate automatically, if desired, by means of pressure or flow transducers in the output lines. If a drop in pressure or flow is detected, a signal could be sent to operate the treatment fluid pump to clear any paraffin or other buildup until normal well output pressure or flow is obtained, whereupon the treatment pump is stopped.
While the structure and function of the present invention has been described generally in connection with subterranean fluid wells of various types (water, oil, etc.), it should be noted that the present tool embodiments are of particular value in the oil industry for the elimination of paraffin buildup along the internal walls of the production tube string in such a well, as described further above. The treatment of the oil from a point before or below that at which the paraffin begins to solidify, throughout the remainder of the surface treatment and storage system at the well, ensures that well production will be maintained and that downtime for cleanout and treatment of paraffin residue in the surface system will be eliminated. Thus, the present tool 10 will be seen to pay for themselves in short order in the oil industry, and their usefulness in other subterranean fluid well treatment fields will be appreciated as well.
It is to be understood that the present invention is not limited to the sole embodiments described above, but encompasses any and all embodiments within the scope of the following claims.
Although the invention has been described with reference to a particular embodiment, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments as well as alternative embodiments of the invention will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that the appended clams will cover any such modifications or embodiments that fall within the scope of the invention. | A well treatment tool is installed along the sucker rod string of a well, within the surrounding production tube string. The tool provides for the distribution of a treatment fluid (solvent, etc.) within the fluid being pumped or flowing from the well. The tool receives treatment fluid through the hollow sucker rod string, and distributes the fluid through a valve which is set at a predetermined pressure. When the treatment fluid pumped down the sucker rod string from the surface exceeds the predetermined opening pressure of the valve, the treatment fluid is distributed into the production tube string through one or more passages in the tool. The present tool may be used simultaneously with well production, with fluid (oil, etc.) rising up the production tube string, carrying the treatment fluid therewith. The treatment fluid is thus distributed throughout the local fluid processing system, including pipelines from the well, any initial treatment operations, and any storage tanks. The present tool is particularly well adapted for the treatment of paraffin buildups within the production tube string of an oil well. The present tool may be used with both pumping wells and flowing (e.g., artesian) wells. | 4 |
BACKGROUND OF THE INVENTION
This application is a continuation of application Ser. No. 680,637, filed 12/12/84.
The invention relates to a device for converting the rotary motion of an eccentric driven by a motor shaft into a reciprocating motion of a working tool coupled with a shaft pin in electrically powered appliances, in whose housing a double-armed rocker arm equipped with a shaft pin is pivotably mounted, and a connecting arm linking the double-armed rocker arm with the eccentric is provided whereby the double-armed rocker arm and the connecting arm are coupled together by an articulation, whose articulation midpoint lies on the lengthwise axis of the corresponding lever arm.
German Pat. No. 24 09 592 teaches a dry shaver with a rotary motor, an oscillating lower cutter, and a crank and rocker linkage to convert the rotary motion of the motor into the oscillating motion of the lower cutter, whereby the motor shaft is aligned parallel to the lengthwise axis of the rocker arm engaging the lower cutter and is laterally displaced by the length of the crank rod. The crank rod is connected both by an elastic gimbal suspension to the eccentric on the motor shaft and by a ball joint with the rocker arm motion. This type of motion transmission means of two differently designed and spatially separated articulation is very expensive and extremely problematical from the engineering standpoint because of the tolerances to be maintained in the bearings and articulated parts. The useful power destroyed by the motion transmission device is very high. The oscillating behavior of the rocker arm, in which a constant amplitude is deemed optimum in a predetermined rpm range of the motor, is highly negative.
Jappanese Patent Y2 57-57650 teaches a dry shaver with rotary motor, an oscillating lower cutter, and a crank and rocker linkage to convert the rotary motion of the motor into an oscillating motion of the lower cutter. The motor shaft is aligned parallel with the lengthwise axis of the rocker arm engaging the lower cutter and is disposed laterally offset by the length of the crank rod. The crank rod is made fork-shaped in the vicinity of the rocker arm, whereby the rocker arm engages this fork and is held pivotably by means of an articulation pin in the fork. The crank rod is also connected by an eccentric drive provided in the connecting rod head with the motor shaft of the rotary motor. An important disadvantage of this type of motion transmission is that the swing height of the rocker arm can only be compensated by the crank rod taking into account considerable pressure stresses and high frictional forces at the two bearing points, the articulation pin and the eccentric drive, of the crank rod, whereby a high percentage of the power to be transmitted is destroyed, and must necessarily be made up by increasing the amount of energy supplied. Increased energy consumption makes itself perceptively disadvantageous to the user of such a device by virtue of the fact that he must recharge or replace the batteries after a short period of use, for example after a small number of shaves.
SUMMARY OF THE INVENTION
The goal of the present invention is to provide a device of the species recited hereinabove, wherein conversion of the rotary motion into a reciprocating motion is accomplished with the smallest possible losses in driving energy. The device is intended to ensure unimpeded motion in all required degrees of freedom with low friction and little noise.
According to the invention this goal is achieved by virtue of the fact that all motion axis of the double-armed rocker arm and the connecting arm meet directly or indirectly at the articulation midpoint.
According to the invention, the midpoint of the articulation coincides with the point of intersection of the lengthwise axis of the corresponding lever arm of the double-armed rocker arm and the connecting arm.
The solution according to the invention is characterized in particular by low power consumption and an improved amplitude behavior over rpm variations, due to the fact that only one articulation is used to convert the motion, the midpoint of which articulation combines all degrees of freedom. This articulation with its articulation midpoint lying on the lengthwise axis of the corresponding lever arm of the double-armed rocker arm, at which all the motion axes of components executing a swiveling motion meet, makes it possible, as a result of the power introduced at this articulation midpoint, among other things to reduce the stability of the double-armed rocker arm and connecting arm, resulting in a decrease in the total mass of these components. In addition, the diameter of the bearing of the double-armed rocker arm as well as of the bearing pin which engages the connecting arm can be reduced, resulting in reduced friction at these bearing points. A number of different embodiments is possible within the framework of the present invention, each of which confers additional advantages.
An especially simple and economically manufacturable embodiment of the invention is characterized by the fact that a bearing pin is provided on the lever arm, associated with the connecting arm, of the double-armed rocker arm, said pin extending along the lengthwise axis of said rocker arm, by the fact that the rigidly designed connecting arm comprises at one end a bearing bore with a relatively thin wall thickness, which surrounds the bearing pin with a predetermined amount of play, by the fact that the bearing pin is provided with a stop, against which the connecting arm abuts, by the fact that the stop as well as the area around the bearing bore are so shaped that unimpeded rolling in the contact area in all directions of motion of the connecting arm and double-armed rocker arm is ensured.
The articulation described with reference to the above features ensures direct coincidence of the motion axes of the connecting arm and the double-armed rocker arm at the midpoint of the articulation which lies on the lengthwise axis of the rocker arm.
Another embodiment is characterized by the fact that the connecting arm is rotatably mounted on the double-armed rocker arm, and is rotatable about lengthwise axis of the corresponding lever arm of said rocker arm by a bearing pin and by the fact that the connecting arm comprises an articulation pair/film hinge pair, whose middle/bending axis intersects the lengthwise axis of the corresponding lever arm of the double-armed rocker arm. In this embodiment, the locally defined middle/bending axis of the connecting arm, which runs through the midpoint of the articulation, ensures that the motion axes of the connecting arm are directed indirectly to the midpoint of the articulation.
In another design of the latter embodiment, provision is made for the connecting arm to have a fork-shaped end, for the fork tines of the connecting arm to be connected together by a stud, for an arm with a bearing bore extending in the direction of the fork opening to be provided on the stud.
Another advantage of the invention consists in the fact that it allows designs which especially relate to adaptation of this device to predetermined installation criteria in appliances of the stated species, without additional structural expense. For this purpose, the lengthwise axis of the lever arm of the double-armed rocker arm which is associated with the connecting arm runs at an angle to the lengthwise axis and intersects lengthwise axis Z of the connecting arm at right angles.
In addition, the motion conversion shown according to the invention is not limited to a certain lever ratio of the two lever arms of the double-armed lever. The latter can be varied according to the specific application.
Further features, advantages, and details of the invention will be apparent from the following specification and the drawing in which preferred embodiments of devices for motion conversion, for example for installation in a dry shaver, are shown:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a double-armed rocker arm and connecting arm as well as their motion axes;
FIG. 2 is a perspective view of a double-armed rocker arm, with a rigid connecting arm coupled thereto;
FIG. 3 is an articulation according to FIG. 2 with a lengthwise section through the connecting arm;
FIG. 4 is a perspective view of a double-armed rocker arm and a fork-shaped connecting arm with film hinges;
FIG. 5 is a double-armed rocker arm and a fork-shaped connecting arm with fastening means in section; and
FIG. 6 is a schematic representation of structural variations of the double-armed rocker arm.
DETAILED DESCRIPTION
FIG. 1 shows the double-armed rocker arm at 1, the lever arm provided with a shaft pin for the working tool to be driven, e.g. the cutter block of a dry shaver, at 2 and the lever arm associated with connecting arm 4 at 3. The double-armed rocker arm comprises a bearing bore 5, whose pivot axis is designated y. The bearing bore is engaged by a shaft pin, not shown, located on a housing of the appliance. The pivot point of the lengthwise axis x running through lever arms 2 and 3 lies on pivot axis y.
At the bottom dead center of radial pivoting motion RS of double-armed rocker arm 1 about pivot axis y, the lengthwise axis z of connecting arm 4 intersects lengthwise axis x at right angles. Articulation midpoint 7 is located at the intersection of the two lengthwise axes x and z. Crank arm 4 is provided with a connecting rod or crank head 6, in whose bore 14 with central axis K an eccentric pin for driving purposes, not shown, engages. The circular motion of central axis K of crank head 6 is converted by crank head 6 and connecting arm 4 mounted at articulation midpoint 7 into an angular component WK and a linear component LK. Linear component LK causes a radial pivoting motion RS of double-armed rocker arm 1 with its lengthwise axis x, with a linear component LK and a linear height component HK.
The above-mentioned motion components, hereinafter referred to generally as motion axes, are deliberately brought together, at an articulation midpoint 7 located on lengthwise axis x of the double-armed rocker arm and articulated by means of a single articulation which combines all the degrees of freedom.
FIG. 2 shows an articulation combining all the degrees of freedom between double-armed rocker arm 1 and connecting arm 4 at whose articulation midpoint all the motion axes are directly combined.
On double-armed rocker arm 1, consisting of lever arms 2 and 3 and bearing bore 5, a shaft pin 8 is provided on lever arm 2 for coupling a working tool and a staggered bearing pin 9 is provided on lever arm 3. Lengthwise axis x of double-armed rocker arm 1 runs both through shaft pin 8 and through bearing pin 9. The step provided on the bearing pin divides the latter into a pin part 9.1 with a larger diameter and a pin part 9.2 with a smaller diameter, whereby the transition between the two parts of the pin is termed stop 10. Rigidly designed connecting arm 4 abuts stop 10, which has a rounded shape. Bearing pin 9.2 is guided through a bearing bore 11 (FIG. 3) provided in connecting arm 4. Pin parts 9.1 and 9.2 of bearing pin 9 can be formed directly on lever arm 3. Pin part 9.2 however can consist of a metal pin inserted in pin part 9.1.
A crank head 6 with bore 14 to accept an eccentric pin is provided on connecting arm 4 at the end opposite bearing bore 11.
FIG. 3 shows details of the articulation shown in FIG. 2 with a partial section through connecting arm 4. In the vicinity of the articulation, the wall thickness of connecting arm 4 is sharply reduced. This is achieved, for example by two groove or trough-shaped depressions 12 and 13 opposite one another, through whose deepest points lengthwise axis x of the double-armed rocker arm passes. The central axis of bearing bore 11 lies on lengthwise axis x. The spherically rounded stop 10, during the pivoting motion of lever arm 3 with its lengthwise axis x and the pivoting motion of connecting arm 4, rolls over a partial area around pivot axis x within trough-shaped depression 13 at its wall. Trough-shaped depression 13 is shaped such that it allows unimpeded rolling or unimpeded motion of these articulated parts. This also applies to the play between the wall of bearing bore 11 and pin part 9.2, which must be sufficiently large for the pivoting motion of bearing pin 9.2 with lengthwise axis x, at the given wall thickness of connecting arm 4 in the vicinity of bearing bore 11, to take place unimpeded within bearing bore 11. FIG. 4 shows a double-armed connecting arm 1 pivotable about bearing bore 5, whose lengthwise axis x passes centrally through shaft pin 8, bearing bore 5, and bearing pin 9.
Crank arm 4 is made fork-shaped. Fork tines 17 and 18 are brought together both to a fork handle 19, at whose end crank head 6 is formed, and are also connected to one another by a stud 20. An arm 21 extending into the fork opening is formed on stud 20. Fork tines 17 and 18 are each provided with a film hinge 22 and 23, whose common middle/bending axis BM intersects lengthwise axis x. Film hinges 22, 23 are so designed that the flexible tines, during the radial pivoting motion RS of lever arm 3, ensure an S-shaped bent form to compensate for the height component HK of lever arm 3.
Crank arm 4 is connected both by bore 14 in crank head 6 with eccentric pin 15 of eccentric 16 and also by a bearing bore provided in the arm to articulate pivotably about angular component WK on bearing pin 9.
Further details of the articulation of connecting arm 4 and lever arm 3 are shown in FIG. 5. Bearing pin 9 provided on lever arm 3 consists of the two pin parts 9.1 and 9.2. The stop 10 formed in the transition area between the two pin parts by their different diameters is likewise made flat, like the area of arm 21 formed on stud 20 of connecting arm 4 which surrounds bearing bore 11. In the assembled state, bearing bore 11 surrounds pin part 9.2 with a small amount of play, whereby arm 21 abuts stop 10. The articulation midpoint of this articulation lies on lengthwise axis x running through bearing bore 11, within bearing bore 11. At this articulation midpoint, all motion axes of double-armed rocker arm 1 and connecting arm 4 come together both directly and indirectly.
The fastening means, in the form of two hooks 24 and 25 formed on arm 21, engage a circumferential groove 26, provided on pin part 9.1, and serve to facilitate assembly of double-armed rocker arm 1 and connecting arm 4. To guide hooks 24 and 25 into groove 26, pin part 9.1 has two grooves 27 running parallel to lengthwise axis x, one of which is visible in FIG. 5. Hooks 24 and 25 are so designed that they do not contact any part of pin part 9.1 when arm 21 abuts stop 10.
The articulated connection between connecting arm 4 and double-armed rocker arm 1 allows a plurality of structural variations in double-armed rocker arm 1. Several of them are shown schematically in FIG. 6, whereby the basic version described in the previous figures is shown by continous lines and two variations are shown by dashed lines.
The basic version consists of double-armed rocker arm 1 with the two lever arms 2 and 3, shaft pin 8, bearing pin 9 and pin parts 9.1 and 9.2, connecting arm 4, eccentric pin 15, eccentric 16, and rotary motor 28. The length A of lever arm 2 extends from the center of bearing bore 5 to a coupling point 29 of a working tool, not shown, which engages the shaft pin and the length B of lever arm 3 extends from the center of bearing bore 5 up to articulation midpoint 7. Coupling point 29, the midpoint of bearing bore 5, and the articulation midpoint lie on the lengthwise axis x of the double-armed rocker arm. The lever ratio A:B of lever arms 2 and 3 can be A=B or can be different, i.e. A is less than B or A is greater than B, depending on the individual application.
It is also possible to bend lever arm 3 associated with connecting arm 4 at an angle. In these cases, it is merely necessary to ensure that the lengthwise axis of bent lever arm 3, designated x 1 in FIG. 6, intersects lengthwise axis x either at the midpoint of bearing bore 5 or in lever arm 3 and that lengthwise axis z of connecting arm 4 intersects lengthwise axis x 1 of bent lever arm 30 at right angles.
While embodiments and applications of the invention have been shown and described, it will apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein described. | Device for converting the rotary motion of an eccentric driven by a motor shaft into an oscillating motion of a working tool in electrically powered appliances, consisting of a double-armed rocker arm and a connecting rod connecting the rocker arm with the eccentric, as well as a single articulation at whose articulation midpoint all the motion axes of the connecting rod and rocker arm meet directly or indirectly. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 61/151,120, filed on Feb. 12, 2009, the complete disclosure of which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to devices and methods for handling and controlling animals, including but not limited to domesticated dogs.
BACKGROUND OF THE INVENTION
[0003] Traditional methods of walking or controlling an animal often present difficulties and dangers to the animal's handler. When utilizing current leashes and other similar animal control devices, the animal often has leverage or control advantages over the handler, especially when the animal has been excited or startled. Existing devices used to walk or handle an animal only offer a basic handle design, usually consisting of a simple strap that is formed in a loop and reattached to itself. These simple existing designs focus the point of control in the leash handle, and consequently, in the handler's single hand. Particularly when a handler is trying to control an animal of significant size and strength, the handler often tries to modify the basic leash or similar control device by employing awkward, ineffective, and often-times dangerous methods such as wrapping the leash around the back of the handler's arm multiple times in an attempt to gain leverage over the animal by distributing the force of the animal to other regions of the handler's arm such as the forearm and bicep areas.
[0004] Manually wrapping the strap of a leash around the arm or other body parts, however, can create a tourniquet-like effect causing pain and the restriction of blood flow. If the leash or other control device is inappropriately wrapped around the handler's wrist, there can also be substantial injury to the wrist when the animal exerts a sudden force on the leash.
[0005] Other existing leashes that are not necessarily manual modifications, but rather, leashes specifically designed to provide the handler with greater leverage over the animal, are likewise awkward, ineffective, and potentially dangerous. For example, devices that wrap around the handler's waist, torso, or lower extremities, such as those described by U.S. Pat. No. 6,932,027, issued to Whitney; U.S. Pat. No. 6,626,131, issued to Moulton III; U.S. Pat. No. 6,450,129, issued to Flynn; U.S. Pat. Nos. 5,950,569 & 5,842,444, issued to Perrulli; and U.S. Pat. No. 5,806,466, issued to Pintor, can cause injury or pain to the handler's lower back when the animal exerts a sudden force on the leash to which the handler's waist, torso, or lower extremities are integrally tethered. If the force of the animal is great enough, the sudden movement may even cause the handler to slip and fall, and sustain even greater injury.
[0006] There is, therefore, a long unsolved need for a leash and method of handling an animal, including but not limited to domesticated dogs, that facilitates walking or handling the animal by providing the handler with greater control and leverage over the animal without utilizing a device or method that could potentially injure the handler.
SUMMARY OF THE INVENTION
[0007] The present invention is generally directed to a method and apparatus to safely facilitate walking or handling an animal, including but not limited to a domesticated dog, by providing the handler with greater leverage and control over the animal. In one embodiment of the present invention, the handler's hand grips a handle, preferably cushioned and adjustable; the handle is connected to a standard leash or similar device, and is also connected to an arm pad, which is also preferably cushioned and adjustable. The arm pad can be pulled back and positioned around the rear area of the handler's upper arm near the triceps region, thereby allowing the handler to maintain a substantially 90 degree angle, or “sling position,” when handling the animal.
[0008] The sling position evenly distributes any force exerted by the animal throughout the entire arm of the handler and allows the handler to effectively counter the force of the animal by utilizing the stronger regions of the handler's arm, such as the handler's forearm, bicep, and shoulder regions. This provides the handler with significantly greater leverage and control over the animal without the risks associated with straps tightening around or restricting the handler's arm, waist, torso, or lower extremities.
[0009] It is therefore an object of the present invention to provide a safer and more maneuverable method and apparatus for any handler that wishes to walk or handle an animal. It is a further object of the present invention to provide a much needed and improved method and apparatus for handlers of professional work dogs, such as K-9 units and other law enforcement dogs that are known to exert a great amount of force on the handler.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 depicts a perspective view of the leash apparatus.
[0011] FIG. 2 depicts a handler gripping the handle of the leash apparatus in a conventional position.
[0012] FIG. 3 depicts a handler gripping the handle of the leash apparatus in a sling position.
[0013] FIG. 4 depicts a close-up view of the connection between the handle and arm pad of the leash apparatus.
[0014] FIGS. 5 and 5 a depict close-up views of alternative connections between the handle and arm pad of the leash and arm pad apparatus.
[0015] FIG. 6 depicts another embodiment of the leash apparatus incorporating a second grab handle that can be engaged by the handler's second free arm for added control and leverage of the animal; FIG. 6 a depicts the strand that forms the grab handle lying flat against the main leash strand of the leash apparatus when not engaged by the handler.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] With reference to FIG. 1 , the leash apparatus of the present invention is generally comprised of a main leash strand 1 preferably having a substantially flat geometric configuration and preferably made of a durable, flexible, webbed material such as nylon. Other possible materials may include rope, leather, chain or any other material suitable for the purpose. The cross-section of the main leash strand can also be of any geometric configuration. Preferably, main leash strand 1 can stretch to a length of approximately six feet from hook assembly 2 to handle 3 . Longer and shorter lengths are also acceptable. Preferably, the width of main leash strand 1 is approximately between one half of an inch and two inches; and even more preferably between three fourths of an inch and one inch.
[0017] As further depicted in FIG. 1 , hook assembly 2 is attached to a first end of main leash strand 1 . Hook assembly 2 is preferably configured to attach directly to a neck collar or harness worn by a dog or animal using any configuration suitable for the purpose. Hook assembly 2 can be made of any hard metal, such as stainless steel, but can also be made of any durable material suitable for the purpose. Although many types and sizes of hook assemblies are suitable for the device, including but not limited to swivel-and-bolt style combinations, in a preferred embodiment of the present invention, hook assembly 2 is approximately three inches in length, one inch in width, and has a squared-end opening whereby a first end of the main leash strand 1 passes through the opening and attaches to the main leash strand by stitching or other attachable means, thereby securing the main leash strand 1 to the hook assembly 2 .
[0018] As shown in FIG. 2 , handle 3 can be gripped by the handler in a conventional handling position, particularly when the animal is in a docile state and is not exerting any sudden or excessive force on the handler. Preferably, handle 3 is approximately four and one half inches long and approximately one inch wide, but can also be any dimension suitable for the purpose; handle 3 can be made out of rubber, neoprene, foam, or any other material suitable for the purpose; and handle 3 can have any cross-section geometric configuration that permits the handler to grip handle 3 . In yet another preferred embodiment of the present invention, handle 3 is further comprised of a rigid reinforcement member that is passed through a hollow opening in handle 3 so that the handle does not bend or flex from the force exerted by the animal or handler. The rigid reinforcement member is preferably tubular in shape, but can have any geometric cross-sectional configuration suitable for the purpose. The rigid reinforcement member can also be made out of PVC, plastic, metal, or any other durable material suitable for the purpose.
[0019] With reference to FIGS. 1 through 5 , handle 3 is further connected to arm pad 4 . Arm pad 4 can be made out of foam, neoprene or any other material suitable for the purpose. Preferably, arm pad 4 is substantially rectangular, approximately six inches in length, and approximately two and one half inches in width, but can also have any geometric configuration or dimension suitable for the purpose.
[0020] As shown in FIG. 3 , arm pad 4 can be positioned on the handler's upper arm near the triceps region 14 while the handler's hand 15 grips handle 3 . In this sling position, the handler's arm naturally maintains a substantially 90 degree angle, thereby evenly distributing any force exerted by the animal throughout the entire arm and shoulder area of the handler and allowing the handler to effectively counter the force of the animal by utilizing the stronger regions of the handler's arm, such as the handler's forearm region 16 and biceps region 17 .
[0021] With reference to FIG. 4 , in a preferred embodiment of the present invention, main leash strand 1 extends through a hollow opening in handle 3 ; extends through sleeve 5 in arm pad 4 ; once again extends through the hollow opening of handle 3 ; and a second end 6 of main leash strand 1 attaches, by stitching or any other suitable attaching means, to a section of main leash strand 1 , preferably between the hook assembly 2 and handle 3 .
[0022] With further reference to the configuration depicted in FIG. 4 , when the handler grips handle 3 and simultaneously pulls arm pad 4 away from the handle, the length of main leash strand 1 between handle 3 and arm pad 4 increases, while the length of main leash strand 1 between handle 3 and the second end 6 of main leash strand 1 decreases. Conversely, when the handler grips handle 3 and the main leash strand is simultaneously pulled from its first end, the length of main leash strand 1 between handle 3 and arm pad 4 decreases, while the length of main leash strand 1 between handle 3 and the second end 6 of main leash strand 1 increases. This configuration thereby allows the handler to adjust the length of main leash strand 1 between handle 3 and arm pad 4 to the approximate length of the handler's forearm.
[0023] As shown in FIG. 5 , in an alternative embodiment of the present invention, main leash strand 1 traverses a hollow opening of handle 3 , and a second end of main leash strand 6 attaches, by stitching or any other suitable attaching means, to a section of main leash strand 1 , preferably between the hook assembly 2 and handle 3 . Alternatively, as depicted in FIG. 5 a, handle 3 is secured to main leash strand 2 by attaching a second leash strand and third leash strand to the main leash strand 1 so that the second leash strand, third leash strand, and main leash strand 1 form a substantially triangular configuration when handle 3 is gripped by the handler. In this embodiment, second leash strand attaches to a first end 7 of handle 3 , and third leash strand attaches to a second end 8 of handle 3 . With further reference to FIG. 5 , arm pad 4 connects to handle 3 by a connecting strand 9 extending through arm pad sleeve 5 and handle 3 . Connecting strand 9 can be made of a flexible or elastic material or any other material suitable for the purpose. Alternatively, as depicted in FIG. 5 a, two or more connecting strands 10 and 11 attach to a first end 12 and a second end 13 of arm pad 3 and also attach to first and second ends 7 and 8 of handle 3 .
[0024] As shown in FIG. 6 a, in another embodiment of the present invention, main leash strand 1 is further comprised of grab handle 18 . In this embodiment, when the handler's first hand has engaged handle 3 , whether in a conventional handling position or in a sling position, the handler's second hand can engage grab handle 18 and thereby increase the handler's leverage and control over the animal. As depicted in FIG. 6 , in a preferred embodiment of the present invention, grab handle 18 will lay flat against the main leash strand 1 when the handler does not desire to engage grab handle 18 .
[0025] Although details of specific implementations and embodiments are described above, such details are intended to satisfy statutory disclosure obligations rather than to limit the scope of the following claims. Thus, the invention is defined by the claims, not limited by the specific features described above. The invention is claimed in any form that falls within the proper scope of the appended claims, appropriately interpreted in accordance with the doctrine of equivalents. | The present invention is generally described as a method and apparatus for handling an animal, including but not limited to a domesticated dog, and more particularly is a leash apparatus made primarily of a durable strand material, such as nylon webbing, that facilitates the activity of walking or handling the animal. | 0 |
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured, used and licensed by or for the U.S. Government for governmental purposes without the payment to me of any royalty thereon.
BACKGROUND OF THE INVENTION
This invention relates to systems for transmitting information from the bottom of a bore hole to the surface by way of pressure pulses created in a circulating mud stream in the drill string. More particularly, this invention relates to an apparatus for changing the resistance to the flow of the mud stream to create pressure pulses therein.
The usefulness of obtaining data from the bottom of an oil, gas, or geothermal well during drilling operations, without interrupting those operations, has been recognized for many years. However, no proven technology reliably provides this capability. Such a system would have numerous benefits in providing for safer and less costly drilling of both exploration and production wells.
Any system that provides measurements while drilling (MWD) must have three basic capabilities: (1) to measure the downhole parameters of interest; (2) to telemeter the resulting data to a surface receiver; and (3) to receive and interpret the telemetered data.
Of these three essential capabilities, the ability to telemeter data to the surface is currently the limiting factor in the development of an MWD system. The use of bottom-hole recorders has demonstrated the ability of currently available sensors to continuously measure the bottom-hole environment.
For safety, it is of interest to predict the approach of high-pressure zones to allow the execution of the proper kick preventative procedures. A downhole temperature sensor and gamma-ray log would be useful for this prediction. The downhole sensing of a kick would give the driller an earlier, more accurate warning than is currently available in this potentially dangerous situation. To save time and significantly reduce costs, continuous measurement of the drill bit's position would be useful during directional drilling operations.
While several downhole sensors are in general field use, none provide a signal to the surface without interrupting the drilling operation or requiring special "trips" be made when the drill string length is to be changed.
Four general methods are being studied that would provide transmission of precise data from one end of the well bore to the other: mud pressure pulse, hard wire, electromagnetic waves, and acoustic methods. At this time, the mud-pressure-pulse method seems to be closest to becoming commercially available.
The method currently being pursued to generate mud pressure pulses involves the use of a mechanical valve to modulate the resistance to the flow of the mud through the drill string. The advantages of this method are a relatively high-speed signal transmission (about 4000 to 5000 feet per second) and ready adaptability to existing equipment. (The only required modification to downhole equipment is the addition of a special drill collar near the bit that contains the pressure-pulse generating valve, the downhole sensors, and the related control apparatus). The disadvantages of this method are a relatively slow data rate (from 6 to 60 seconds for each measurement) and the poor reliability of mechanically moving parts exposed to the downhole environment.
SUMMARY OF THE INVENTION
Accordingly it is an object of this invention to provide a mud pulse transmitter having a higher data transmission rate.
It is a further object of this invention to provide a mud pulse transmitter utilizing fluidic components to eliminate the sealing problems associated with moving part valves.
Yet another object of this invention is to provide a mud pulse transmitter capable of controlling the full mud flow by mechanically valving a small amount of flow in a control path.
To achieve the above objects the present invention utilizes a vortex valve controlled by a fluidic feedback oscillator. One of the output channels of the oscillator supplies the tangential inlets of the vortex valve while the other oscillator output bypasses the vortex valve. The main or radial inlets of the vortex valve are supplied by the main mud flow. Since the vortex valve will be throttled when it receives flow in its tangential inlets and open when there is no fluid supplied to the tangential inlets, the vortex valve will produce pressure oscillations in the upstream main mud flow corresponding to the oscillations produced by the feedback oscillator. The oscillations are controlled by restricting flow in the feedback channels of the fluidic feedback oscillator.
Additional objects, features, and advantages of the instant invention will become apparent to those skilled in the art from the following detailed description and attached drawings on which, by way of example, only the preferred embodiment of the instant invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the transmitter of the present invention as it will appear coupled in a drill string.
FIG. 2 is an exploded view of the transmitter of the present invention.
FIG. 3 is a detailed view of the fluidic feedback oscillator illustrated in FIG. 2.
FIG. 4 shows a detailed section view (4--4) of one embodiment of the variable resistor used in the feedback paths of the oscillator of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is shown a portion of the drill string 10 housing the telemetry equipment of the present invention. The drill string 10 is rotated by a typical drilling rig (not shown) to drive a rotary drill bit (not shown) to excavate a borehold through the earth. While drill string 10 is being rotated substantial quantities of a suitable drilling fluid, drilling mud, are continuously circulated down through the drill string to cool the drill bit, counter pressure formation fluids, and carry earth borings to the surface. As is well known in the art, the mud stream flowing down through the drill string is well suited for the transmission of pressure signals to the surface at the speed of sound in the particular mud stream.
In accordance with the principles of the present invention, data transmitting means 11, including vortex triode 12 controlled by fluidic feedback oscillator 14, is located in a segment of drill string 10. Transmitter 11 serves to produce pressure signals in the drilling mud which are transmitted to the surface and decoded by suitable signal detecting and recording devices, as is well known in the art. Transducers 15 are provided to sense such downhole conditions as pressure, temperature, and drill-bit position information as well as various other conditions. The transducers 15 produce electrical signals which are coupled to encoder 16 to produce digital hydraulic signals to control the feedback paths of fluidic oscillator 14, thereby controlling transmitter 11. Hydraulic oil pressure as well as electrical power is generated by a mud powered turbine 17. This turbine 17 provides power to transducers 15 and encoder 16.
Turning now to FIG. 2, there is depicted an exploded view of transmitter 11. Transmitter 11 includes fluidic feedback oscillator 14 mounted on oscillator mounting section 20, first and second adapter sections 30 and 40, control manifold section 50, inlet section 60, vortex section 70, and discharge section 80. Sections 20, 30, 40, 50, 60, 70 and 80 are each designed to have a constant cross-section for ease of manufacture. The sections are all diffusion bonded together in one segment of the drill string.
Sections 60, 70 and 80 form a vortex triode while sections 20, 30, 40 and 50, in effect, form a manifold enabling fluidic oscillator 14 to control the triode. Some of the mud flow coming down the drill string 10 will pass through transmitter 11 by means of passages 22, 32, 42, 52 and 62. When the main flow reaches vortex section 70 it will enter vortex chamber 78 by way of main radial inlets 72. The flow will then exit from vortex chamber 78 by way of vortex drain 82.
The discharge end of fluidic oscillator 14 is mounted in hole 24 of oscillator mounting section 20. Oscillator 14 has two outlets and is mounted so that one outlet discharges into passage 34 and the other outlet discharges into passage 36 of first adapter section 30. Oscillator 14 switches its discharge from one outlet to the other, in a manner to be discussed subsequently, thereby controlling the operation of the vortex triode. The two diverging paths taken by the discharge of oscillator 14 are a bypass, formed by passages 34, 44, 54, 64, 74 and 84, and a control path formed by passages 36, 46, 56, 66 and terminating in tangential control inlets 76. When oscillator 14 is discharging to the bypass no flow will pass through the tangential control inlets 76. Accordingly, the main flow will pass through radial inlets 72 and flow radially into vortex chamber 78 and axially out vortex drain 82, with no tangential velocity component. With no tangential velocity component, the flow through vortex chamber 78 encounters relatively little flow resistance. Now when the output oscillator 14 is switched to the control path, the control flow will enter vortex chamber 78 through tangential control inlets 76. The tangential control flow will induce vortex flow in vortex chamber 78 and greatly increase the flow resistance to the main flow, as is well known in art. Thus, as the output of oscillator 14 switches back and forth between the bypass and control path, pressure oscillators will be created in the main flow which will be transmitted upstream to the surface at the speed of sound in the drilling mud. The main and control flow paths should be sized such that when main and control flow exist simultaneously in said vortex valve, the two flow rates are approximately equal.
FIG. 3 shows fluidic oscillator 14 with its cover partially removed. The oscillator passages are formed by milling out the channels in block 86. Fluid, drilling mud, is supplied to power chamber 88 through a hole 89 in the coverplate 102. The mud exits power chamber 88 through power nozzle 90 which forms the flow into a jet. The jet then flows out one of the outlets 96 and 98. If, for example, the jet flow is through outlet 96, some of the flow will be fed back through feedback channel 92. This feedback flow will serve to deflect the power jet to outlet 98 whereupon feedback channel 94 will serve to deflect the power jet back to outlet 96. In this manner the output from oscillator 14 will oscillate between outlets 96 and 98. Thus, as described above, the fluidic feedback oscillator 14 will cause the vortex triode formed by sections 60, 70 and 80 to cycle between its high and low flow resistance modes of operation. The oscillator 14 is designed to have sufficient hysteresis in its input-output transfer characteristic so that partially closing a feedback passage 92 or 94 will drop the pressure in the feedback line to a valve below that required to make the amplifier switch, thereby preventing oscillation. It will be recognized that as feedback passage 92 or 94 is gradually closed the period of oscillation of oscillator 14 will increase until it ceases to oscillate.
To control the operation of fluidic feedback oscillator 14 and thus enable the transmission of information by the system a hydraulically operated feedback valve is placed in each of the feedback passages 92 and 94. FIG. 4 shows details of the valve for feedback passage 92. The valve structure is formed in oscillator cover 102. A cavity 104 in oscillator cover 102 is closed by diaphragm 108. Diaphragm 108 is held in place by ring 110 which is attached to cover 102 by screws, not shown. Cavity 104 communicates with the hydraulic output of encoder 16 by means of hydraulic lines (not illustrated) connected to inlet 106. When hydraulic pressure is applied to the diaphragm 108 by encoder 16, diaphragm 108 will be forced into feedback passage 92, thereby partially blocking the mud flow. Thus oscillator 14 may be switched off by pressurizing the diaphragm 108 in either of the feedback passages 92 or 94, with the oscillator output exiting through either of outlets 96 or 98, depending on which of the feedback passages 92 and 94 is partially blocked.
From the foregoing it can be seen that transmitter 12 will create pressure pulses in the drilling mud controlled by hydraulic pulses supplied by encoder 16. It will be appreciated that the present invention has provided new and improved apparatus for producing pressure signals in a mud stream capable of carrying information from the bottom of a bore hole to the surface.
Though a single preferred embodiment has been shown and described it will be recognized that various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. For example, it will be recognized that fluidic feedback oscillator 14 would have the same effect if it were designed to have little or no hysteresis and the valves in feedback passages 92 and 94 were designed to fully close. Accordingly, I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described, for obvious modifications can be made by a person skilled in the art. | A mud pulse transmitter is presented for transmitting information by prese pulses to the surface during the drilling of a borehole. A vortex valve is controlled by a fluidic feedback oscillator to generate the mud pulses. The oscillator frequency may be varied or the oscillator turned on and off by valves in the feedback paths of the oscillator, thereby permitting the transmission of information. | 4 |
RELATED APPLICATIONS
[0001] The present application claims the priority of the German Patent Application No. 10 2006 062 129.8 of Dec. 22, 2006, the disclosure of which is herewith incorporated herein by reference. This application is also a divisional of U.S. patent application Ser. No. 12/003,094 filed Dec. 20, 2007, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention refers to a self-propelled road milling machine, especially a cold milling machine, as well as a methods for measuring the milling depth.
[0004] 2. Description of Related Art
[0005] With such road milling machines, the machine frame is supported by a track assembly comprising wheels or caterpillar tracks connected to the machine frame through lifting columns, the lifting columns allowing to maintain the machine frame in a horizontal plane or in parallel to the ground or under a predetermined longitudinal and/or transversal inclination.
[0006] A milling roll for working a ground or traffic surface is supported at the machine frame.
[0007] Near the front end sides of the milling roll height-adjustable side plates are provided as edge protectors at an outer wall of the road milling machine, which side plates, in operation, rest on the ground or traffic surface at the lateral non-milled edges of the milling track. Behind the milling roll, seen in the travelling direction, a height-adjustable stripping means is provided which, in operation, may be lowered into the milling track formed by the milling roll to strip off milling material remaining in the milling track. Further, the road milling machine has a control means for controlling the milling depth of the milling roll.
[0008] It is a problem with known road milling machines that the milling depth can not be controlled accurately enough and that, for this reason, the milling depth has to be measured repeatedly by hand during the milling operation. Especially in cases where a hard traffic surface, e.g. concrete, is milled, the tools are worn heavily so that the milling depth set is corrupted by the decreasing diameter of the cutting circle. For example, the wear of the tools, when milling concrete, can cause a difference in the milling radius of 15 mm after only a few 100 m, so that the measuring of an adjustment of side plates, for example, with respect to the machine frame is not sufficiently accurate. If the milling depth is insufficient, a time-consuming reworking of the milling track has to be carried out. Should the milling track be too deep, more building material has to be applied afterwards in order to achieve the desired ground or traffic surface level.
SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to improve the accuracy of measuring the milling depth during the operation of a road milling machine and to thereby minimize deviations from a predetermined milling depth.
[0010] The invention advantageously provides that at least one measuring means detects the lifting of a first sensor means resting on the ground or traffic surface and/or the lowering of a second sensor means to the bottom of the milling track, the lifting or lowering being effected in correspondence with the present milling depth. From the measured values supplied by the at least one measuring means, the control means can determine the milling depth at the level of the measuring means of the milling roll or the second sensor means.
[0011] Here, the measurement is effected preferably at the level of the stripping means arranged closely behind the milling roll, or immediately behind the stripping means, if a separate sensor means is provided.
[0012] Using the stripping means as a sensor means is advantageous in that no measuring errors are caused by some unevenness in the milling track. It is another advantage that the stripping means is protected against wear at its bottom edge.
[0013] As an alternative, the control means can use the measurement values of the at least one measuring means to determine the current milling depth of the milling roll at the level of the milling roll axis. Preferably, this is done by a calculation that may also take into account an inclined position of the machine frame.
[0014] The measuring means are preferably formed by position sensing means. In one embodiment it is provided that the first sensor means is formed by at least one of the side plates arranged on either side at the front sides of the milling roll so as to be height-adjustable and pivotable with respect to the machine frame. The side plates rest on the ground or traffic surface or are pressed against these, so that a change of their position relative to the machine frame during operation allows for an exact detection of the milling depth, if a measurement of the change of the position of a second sensor means is performed additionally in the milling track relative to the machine frame.
[0015] Also for side plates, there is an advantage that their bottom edges are protected against wear.
[0016] Here, the measuring means may comprise cable lines coupled with the side plates and/or the stripping means, and associated cable-line sensors as the position sensors which measure the changes of the position of the side plates and the stripping means relative to the machine frame or the relative displacement of at least one of the side plates in relation to the stripping means or the second sensor means.
[0017] Preferably, the cable lines coupled with the side plates and the stripping means are arranged transversely to the milling track in a substantially vertical plane extending approximately at the level of the stripping means.
[0018] Hereby, it can be avoided that a measurement error is caused by using different reference planes for the measurement at the side plates with respect to the measurement at the stripping plate.
[0019] To achieve this, it may be provided that a cable line is coupled on the one hand with the stripping means and, on the other hand, with at least one of the side plates via a guide roller, such that a cable-line sensor immediately measures the milling depth, e.g. at the guide roller.
[0020] In another alternative it may be provided that the side plate has a respective measuring means at the side edges facing the side plates, which measures the relative displacement of the stripping means with respect to the at least one adjacent side plate or the relative displacement of at least one side plate with respect to the stripping means.
[0021] According to another alternative embodiment, the stripping means may include at least one height-adjustable beam as the first sensing means, which is guided vertically and linearly in the stripping means and extends transversely to the travelling direction, said beam resting on the ground or traffic surface beside the milling track, the position of the beam relative to the stripping means, preferably with respect to height and/or inclination, being measurable by the measuring means.
[0022] Due to gravity, the side plates may rest on the edges of the ground or traffic surface beside the milling track milled by the milling machine, or they may alternatively be pressed on the edges by hydraulic means.
[0023] The stripping means may also be pressed on the surface of the milling track using hydraulic means.
[0024] The hydraulic means for pressing the side plates on the ground or traffic surface or for pressing the stripping means on the bottom of the milling track may comprise integrated position sensing systems.
[0025] For lifting or lowering the side plates and/or the stripping means, a plurality of, preferably two respective piston/cylinder units with integrated position sensing systems may be provided, whose position sensing signals are used by the control means to calculate the current milling depth from the relative difference between the positions of the stripping means and the at least one first sensor means.
[0026] The control means that receives the position sensing signals from the measuring means is adapted to automatically control the lifted condition of the rear lifting columns, seen in the travelling direction, to establish parallelism between the machine frame and the ground or traffic surface at a desired milling depth.
[0027] The side plates resting on the traffic surface so as to be pivotable with respect to the machine frame may comprise measuring means spaced apart in the travelling direction, the control means being capable to measure the longitudinal and/or the transversal inclination of the machine frame with respect to the ground or traffic surface from the difference between the measurement signals from the side plates and the stripping means.
[0028] The front and/or rear lifting columns may include a position sensing system to detect the lifted condition. The control means that receives the position sensing signals from the measuring means can control the condition of all lifting columns such that the machine frame has a predetermined inclination or a predetermined travel-distance-dependent transverse inclination across the travelling direction.
[0029] Preferably, the current set value for the milling depth of the milling roll is adjusted using the front lifting columns.
[0030] The following is a detailed description of a preferred embodiment of the invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 shows a cold milling machine.
[0032] FIG. 2 illustrates a first sensor means attached to the stripping plate.
[0033] FIG. 3 shows two piston/cylinder units for lifting or lowering the stripping plate of a stripping means.
[0034] FIG. 4 illustrates an optical device for measuring the positional difference between the side plates and the stripping means.
[0035] FIG. 5 shows a cable line measuring means provided between the side plates and the stripping means.
[0036] FIG. 6 illustrates a preferred embodiment.
[0037] FIGS. 7 a, b, c are schematic illustrations of the measurement error occurring at the stripping plate of the stripping means in the absence of parallelism between the machine frame and the ground or traffic surface.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] The road milling machine illustrated in FIG. 1 comprises a machine frame 4 supported by a track assembly having two front chain tracks 2 and at least one rear chain track 3 . The chain tracks 2 , 3 are connected with the machine frame 4 via lifting columns 12 , 13 . It is understood that wheels may be used instead of the chain tracks 2 , 3 .
[0039] Using the lifting columns 12 , 13 , the machine frame 4 can be lifted or lowered or moved to take a predetermined inclined position with respect to the ground or traffic surface 8 . The milling roll 6 supported in the machine frame 4 is enclosed by a roll case 9 which is open at the front, seen in the travelling direction, towards a conveyor belt 11 that conveys the milled material in a front part of the machine frame 4 to a second conveyor means 13 . The second conveyor means 13 with which the milled material may be delivered onto a truck, for example, is not fully illustrated in FIG. 1 because of its length. Behind the milling roll 6 , a height-adjustable stripping means 14 is arranged which, in operation, has a stripping plate 15 engage into the milling track 17 formed by the milling roll 6 and strip the bottom of the milling track 17 so that no milled material is left in the milling track 17 behind the stripping plate.
[0040] Above the milling roll 6 , a driver's stand 5 with a control panel for the vehicle operator is provided for all control functions of the driving and milling operations. It also includes a control means 23 for controlling the milling depth of the milling roll 6 .
[0041] The side plates 10 , arranged on either side near the front end of the milling roll 6 , and the stripping means 14 are provided with measuring means 16 that allow the determination of the current milling depth at the level of the stripping means 14 or the calculation of the milling depth at the level of the rotational axis of the milling roll. Here, the milling depth is determined in a plane orthogonal to the ground or traffic surface, which plane is parallel to the rotational axis of the milling roll and includes the rotational axis.
[0042] The position of a first sensor means, e.g. the side plates 10 , on the ground or traffic surface 8 and/or the lowering of a second sensor means, e.g. the stripping means, can thus be detected. Measuring means 16 , preferably formed by position sensing means, measure the displacements of the sensor means, e.g. the side plates 10 or a beam 20 or the stripping plate 15 , with respect to the machine frame 4 or relative to each other.
[0043] The embodiment illustrated in FIG. 2 shows a beam 20 as the sensor means, resting on the ground or traffic surface 8 and guided at the stripping plate 15 of the stripping means in a slot 24 extending linearly and orthogonally to the bottom edge 19 of the stripping plate 15 . It is understood that two mutually parallel slots 24 can be provided in the stripping plate 15 or that the beam 20 , serving as the sensing means, can be guided in a different manner so as to be height-adjustable at the stripping means 14 . The measuring means 16 , provided in the form of a position sensing means, detects the displacement of the beam 20 with respect to the stripping means 14 . Should two horizontally spaced slots 24 be used, it is possible to separately detect the milling depth on the left side of the milling track 17 and on the right side of the milling track 17 . Moreover, this offers the possibility to determine an inclination of the machine frame 4 with respect to the ground or traffic surface 8 .
[0044] FIG. 3 illustrates another embodiment wherein the stripping plate 15 of the stripping means 14 can be lifted or lowered by means of hydraulic means. The hydraulic means are formed by piston/cylinder units 26 , 28 with an integrated position sensing system. This means that the piston/cylinder units 26 , 28 not only allow for the stroke movement of the stripping means, but moreover generate a position signal.
[0045] As is evident from FIG. 3 , the piston/cylinder units 26 , 28 have one end connected to the machine frame 4 and the other end connected to the stripping plate 15 .
[0046] FIG. 4 illustrates an embodiment, wherein the relative movement between the side plates 10 and the stripping plate 15 is measured directly in order to detect the milling depth of the milling track 17 . To achieve this, elements 38 , 40 of the measuring means 16 are provided, e.g., at the side plates 10 and opposite thereto at the stripping plate 15 , which elements allow for the detection of the relative displacement of the stripping plate 15 with respect to the side plates 10 . This displacement corresponds to the milling depth s in FIG. 4 . For example, such a measuring means, which measures relative displacements, may be formed by an optical system, e.g. by reading a scale with an optical sensor, or by an electromagnetic or inductive system.
[0047] As an alternative and as illustrated in FIG. 5 , the relative position sensing system between the side plates 10 and the stripping plate 15 may also be formed by a cable line 22 in combination with a cable-line sensor 21 . the cable line 22 is coupled with the stripping plate 15 of the stripping means 14 on the one hand and, on the other hand, with at least one of the side plates 10 via a guide roller 35 , so that the signal from the cable-line sensor 21 can immediately indicate the value of the current milling depth.
[0048] The side plates 10 themselves can be used as first sensor means by monitoring their position with respect to the machine frame 4 or the second sensor means by means of a cable line and a cable-line sensor or by means of piston/cylinder units 30 , 32 with integrated position sensing means.
[0049] For example, the measuring means can also measure the displacement of the side plates 10 with respect to the machine frame 4 . Should two measuring means be used, one in front of the side plates 10 and one behind the same, seen in the travelling direction, it is also possible to determine the longitudinal inclination of the machine frame 4 with respect to the ground or traffic surface 8 or to also determine the transverse inclination of the machine frame 4 by a comparison of the measured values for both side plates 10 on both sides of the milling roll 6 .
[0050] FIG. 6 illustrates a preferred embodiment, wherein cable lines 22 comprising cable-line sensors 21 mounted to the machine frame 4 are arranged on both sides of the stripping means 15 . On either side of the machine, the side plates 10 are also provided with cable lines 22 and cable-line sensors 21 fastened at the machine frame 4 . The milling depth s is determined from the difference between the measured values of the cable-line sensors 21 for the side plates 10 and the cable-line sensors 21 of the stripping means 15 . Here, the measurement should preferably be made in the same substantially vertical plane in order to avoid measurement errors.
[0051] FIGS. 7 a to 7 c illustrate the cable-line sensors 21 for the side plates 10 and the stripping plates 14 , the drawings only indicating one cable-line sensor 21 , since the cable-line sensors are arranged one behind the other in substantially the same plane.
[0052] FIGS. 7 a, b, c are to illustrate the case where the ground or traffic surface 8 is not parallel to the machine frame 4 , the measured milling depth value indicated by the measuring means having to be corrected because of an angle error, because a longitudinal inclination of the machine frame 4 corrupts the measurement signal at the level of the stripping plate 15 or a second sensor means near the stripping means 14 . Due to the fixed geometrical relations, i.e. the distance of the stripping plate 15 from the rotational axis of the milling roll 6 , the measured milling depth value can be corrected, knowing the angular deviation from the horizontal in the travelling direction, and the current milling depth at the level of the milling roll axis can be calculated. The angular deviation in the travelling direction may be determined, for example, from the position of the lifting columns 12 , 13 of the caterpillar track assemblies 2 , 3 or the piston/cylinder units 30 , 32 .
[0053] It is further evident from FIGS. 7 a to c , to which extent the side plates 10 are pivotable with respect to the machine frame 4 . Since the piston/cylinder units 30 , 32 are also provided with position sensing systems, these measuring signals may be used as an alternative to cable-line sensors 21 to determine the distance of the side plates 10 from the machine frame 4 .
[0054] FIG. 7 c illustrates the position of the at least one side plate 10 for a ground-parallel position of the machine frame 4 . The stripping plate 15 illustrated in FIGS. 7 a to 7 c is located at the roll case 9 , so that the distance of the stripping plate 14 from the rotational axis to the milling roll 6 can be determined unambiguously in order to allow for a calculation of the milling depth correction should the machine frame 4 not be parallel to the ground.
[0055] The control means 23 can calculate the current milling depth at the level of the milling roll axis from the position sensing signals received, and it can possibly also generate a control signal for a vertical adjustment of the milling roll 6 .
[0056] Preferably, the control means 23 can automatically control the lifted condition of the at least one rear lifting column 13 , seen in the travelling direction, to establish parallelism between the machine frame 4 and the ground or traffic surface 8 or to the horizontal plane or to a predetermined desired milling plane.
[0057] Although the invention has been described and illustrated with reference to specific embodiments thereof, it is not intended that the invention be limited to those illustrative embodiments. Those skilled in that art will recognize that variations and modifications can be made without departing from the true scope of the invention as defined by the claims that follow. It is therefore intended to include within the invention all such variations and modifications as fall within the scope of the appended claims and equivalents thereof. | A method is provided for measuring the milling depth of a road milling machine, the machine being operative to mill a ground surface with a milling roller lowered to a milling depth to create a milling track, the machine including at least one side plate located to at least one side of the milling roller to engage an untreated ground surface, and the machine including a stripping plate operative to be lowered onto the milling track generated by the milling roller. The method includes measuring the milling depth of the milling track, the measuring including detecting a measurement value of a ground engaging sensor engaging the milling track. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to supporting devices such as those used for temporary warning signs and in particular to such support devices which employ adjustable legs and other adjustable components.
2. Description of the Related Art
It has been found convenient to provide temporary warnings alongside vehicle roadways, pedestrian walkways and other locations. Typically, temporary warning systems are erected from a collapsed or small sized storage configuration of relatively small size. Examples of leg release devices may be found in commonly assigned U.S. Pat. Nos. 4,954,008 and 6,315,253. A collapsible sign stand base for use with an upright fiberglass rib is described in U.S. Pat. No. 4,694,601 and other arrangements are shown in U.S. Pat. Nos. 4,548,379; 4,593,879 and 5,340,068. Despite the favorable acceptance of these designs, improvements are continuously being sought.
Temporary warning signs typically employ ground-engaging legs configured with a base to support an upright mast. Typically, when the sign stand is deployed, the ground-engaging legs form an angle with the upright mast that is usually larger than 90°. It is generally preferred that a storage configuration be provided in which the legs are selectively collapsed or folded to a position generally parallel with the upright mast, in order to provide a compact storage and size suitable for construction vehicles and the like.
SUMMARY OF THE INVENTION
Oftentimes, ground-supporting legs are formed from hollow, rectangular tubing. If possible, it is beneficial to locate components of a leg release assembly within the tubing to prevent unintentional snagging with nearby materials. Furthermore, if most all of the leg release components can be located within the tubing, and optimally a compact storage configuration can be realized. However, until the advent of the present invention, at least some of the leg release components have been mounted outside of the legs, in order to provide a rugged construction, sufficient to adequately retain locking pins in a desired position, despite rough handling associated with construction work, as well as vibrations due to wind gusts. Substantially all of the leg release components employed by the present invention are located within the hollow tubular legs. Exceptions include only the locking pin tip and a smooth actuator button.
It is an object of the present invention to provide a release device for use with support arrangements, such as those found in sign stands.
Another object of the present invention is to provide a release device for use with support legs of collapsible sign systems.
Yet another object of the present invention is to provide leg release devices which can be economically fabricated from a minimum number of inexpensive parts.
These and other objects according to principles of the present invention are provided in a sign stand assembly which is comprises of a sign panel, a support base, an upright mast joining the sign panel and support base. This support base includes a plurality of plate portions which define a locking recess, a plurality of legs that are pivotally connecting the legs to the plate portions. A locking pin carried on one leg, for movement toward and away from the locking recess defined by one leg. An actuator that has an end within said leg for pivotally engaging the pivotal connection. An opposed end with an outwardly protruding button that partially extends outside the leg and a medial portion within the leg that defines an opening for receiving the locking pin in interlocking engagement therewith.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is perspective view of a sign stand assembly with a release mechanism according to principles of the present invention;
FIG. 2 is a fragmentary perspective view thereof, with the sign stand assembly shown in a collapsed position;
FIG. 3 is a perspective view of the support base portion thereof;
FIG. 4 is a bottom plan view of the arrangement shown in FIG. 2;
FIG. 5 a is a cross-sectional view taken along the line 5 a — 5 a of FIG. 3;
FIG. 5 b is a cross-sectional view similar to that of FIG. 5 a showing a sequence of operation;
FIG. 6 is a plan view of a spring component thereof;
FIG. 7 is a top plan view of an actuator component thereof;
FIG. 8 is an elevational view of the actuator component;
FIG. 9 is a bottom plan view of the actuator component thereof;
FIG. 10 is a fragmentary bottom plan view of the sign stand assembly; and
FIG. 11 is a fragmentary elevational view of the sign stand of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and initially to FIG. 1, the sign stand assembly is generally indicated at 10 . Sign stand assembly 10 includes a sign panel subassembly 12 , which includes a sign panel 14 supported by a horizontal cross member 16 and a vertical cross member 18 , preferably in the form of a fiberglass rib. The bottom portion 24 of the fiberglass rib 18 is mounted in a rib clamping device 34 , which is supported by a vertical body member 30 . Body member 30 is in turn bolted to a bracket 36 resiliently supported by a spring 50 . With reference to FIGS. 2 and 3, spring 50 is supported by a support assembly 52 including a platform portion 54 supported between side plates 84 . Side plates 84 include ear portions 56 having holes 58 to receive a bolt fastener 92 which provides pivot support for ground-engaging legs 64 (see FIG. 1 ). Ears 56 further include holes 68 which, as will be seen herein, define an extended or operational configuration of the legs as illustrated in FIG. 1 . Ear portions 56 also include holes 72 which define a collapsed storage position for the legs 64 , as illustrated for example in FIG. 2 . As can be seen in FIGS. 5 a and 5 b , the tip 110 of locking pin 106 has a reduced diameter to accommodate the clevis or forked end 170 of actuator 150 (see FIG. 9 ). A shoulder 112 is formed in locking pin 106 for butting engagement with end 170 of actuator 150 . Thus, actuator 150 and locking pin 106 form a linkage assembly. Actuator 150 is received in a slot 66 formed in a side wall of leg 64 (see also FIG. 3 ). Actuator 150 cooperates with leg 64 and locking pin 106 in the manner which maintains actuator 150 captive within the leg. With reference to FIG. 3, it can be seen that the holes 58 which receive the bolt fasteners 92 are located at inner portions of the ears 56 while the locking holes 68 , 72 are located at outer portions.
Referring to FIG. 4, ear portions 56 a , 56 b preferably form part of an integral side plate 84 while ear portions 56 c , 56 d form portions of a second side plate 86 . Preferably, side plates 84 , 86 are mirror images of one another although this feature is optional, and can be omitted, if desired. With further reference to FIG. 4, it can be seen that the legs 64 extend outwardly from outer surface portions 84 a , 86 a of side plates 84 , 86 . Pivot members in the form of bolt fasteners 92 pivotally connect legs 64 to the ear portions of side plates 84 , 86 . The legs 64 are located to one side of the ear portions with the bolt fasteners passing through the legs and ear portions. Bolt fasteners 92 have heads located adjacent the inner surfaces 84 b and 86 b . The bolt fasteners 92 extend through legs 64 and are terminated at their free ends by threaded nut fasteners 94 . As can be seen in FIG. 4, the legs 64 comprise hollow tubing and have a preferred generally square cross-sectional shape. If desired, legs 64 can have an elongated, rectangular or non-square cross-sectional shape. With reference to FIGS. 3 and 4, bolts 92 pass through holes 58 formed in the ear portions 56 of plates 84 , 86 .
With reference to FIGS. 5 a and 5 b , a release assembly is generally indicated at 102 . The release assembly 102 selectively interferes with the legs 56 to lock the legs either in the operational position shown in FIG. 1 or the storage position shown in FIG. 2 . As mentioned, the legs 64 pivot about bolts 92 which are secured to the inner portions of the ears 56 .
Referring to FIGS. 5-10, release assembly 102 includes a locking pin 106 having a head 108 and a tip or free end 110 . The locking pin 106 is carried by leg 64 and preferably extends through the hollow interior of the leg. In FIG. 3, the locking pin 106 is illustrated as extending beyond the outer surface of ear 56 for illustrative purposes. If desired, the locking pin 106 can be configured such that the free end 110 is located at or slightly recessed below the outer surface of ear 56 .
In FIG. 5 a , the locking pin 106 is shown in a fully extended or locked position. In the preferred embodiment, locking pin 106 has a generally cylindrical body although other cross-sectional shapes can be employed, if desired. Locking pin 106 has a first end 110 of reduced diameter compared to the opposed end 108 and remainder of the locking pin body. A stepped shoulder 112 (see FIG. 5 b ) is formed at the transition of the two diameter sizes of the locking pin. As can be seen in FIGS. 5 a and 5 b , shoulder 112 provides abutting engagement with the forked or clevis end 170 of actuator 150 (see FIG. 9 ). As will be seen herein, the large diameter body portion of locking pin 106 is formed with an annular recess for receiving a spring member 120 . If desired, the recess need not be annular, but can be comprised of linear recesses cut parallel to a tangent.
Referring to FIGS. 5 a and 5 b , release assembly 102 further includes a spring member 120 . The spring member 120 is preferably of a flat spring construction having first and second ends and a medial portion between the ends. The first end 122 of the spring defines a relatively shallow recess 124 giving the spring end 122 a forked or stirrup configuration. As schematically indicated in FIG. 3, recess 124 at least partially receives bolt 92 .
Referring again to FIG. 6, the opposed end 128 of spring 120 defines a relatively deeper recess 130 which extends toward spring end 122 . As can be seen in FIG. 6, the recesses 124 , 130 are similar to one another, being located along the longitudinal center line of spring 120 , but differ in their length.
With reference to FIGS. 5 a and 5 b , the free end 128 of spring 120 is free to move back and forth, toward and away from bolt 92 and locking pin 106 . Recess 130 is made sufficiently long so as to permit locking pin 106 to extend through recess 130 in the manner indicated.
Referring again to FIGS. 5-9, release assembly 102 further includes an actuator 150 having a generally curved or C-shaped body including a first end 170 with a recess 154 for receiving bolt 92 . The opposed end 158 of actuator 150 includes a handle or tab 160 having a rounded free end portion. In the preferred embodiment, the tab 160 of actuator 150 is relatively flat although it can take on a non-flat or profiled shape, if desired.
Referring again to FIG. 7, the central portion 156 of actuator 150 defines a stepped portion of reduced width allowing the actuator to be inserted through the slot 66 in leg 64 . The shoulders formed at the transition of the tab 160 and central portion 156 help to hold actuator 150 captive in leg 64 , while allowing the actuator to undergo a rocking action about its curved portion 158 (see FIG. 8 ).
Referring again to FIGS. 5 a and 5 b , as tab 160 is depressed, locking pin 106 is moved in the direction of arrow 166 (see FIG. 5 b ), due to the interlocking of actuator 150 and pin 106 . As tab 160 is depressed, the slotted portion of locking pin 106 pushes against spring 120 causing the spring to compress or flatten slightly, with free end 128 of the spring moving in the direction of arrow 168 (see FIG. 5 b ). This stores spring energy which urges actuator 150 to return to its rest position illustrated in FIG. 5 a . With tab 160 sufficiently depressed (see FIG. 5 b ), the free end 110 of locking pin 106 is made to clear the plate ear portion 56 , allowing the leg to be pivoted about bolt fastener 92 , with the leg assuming its desired orientation. Referring to FIG. 11, a U-shaped shield plate 170 is secured to the outer surface of leg 64 which faces ear portion 56 . Preferably, leg 64 is made of relatively soft aluminum material desirable for its strength and relatively lightweight characteristics. The optional shield 170 toughens the outer surface of leg 64 which would otherwise be subjected to wear as the leg 64 is pivoted between its collapsed or rest position (see FIG. 2) and its extended or operating position (see FIG. 1 ). Shield 170 is preferably made of a mild steel material.
Referring to FIGS. 2 and 11, it will be seen that the tab portion 160 is slightly curved or bent with respect to the adjacent body portion of actuator 150 . This configuration effectively shields the free end 110 of the locking pin 106 and presents a conveniently engageable surface for the operator of the supporting device. When employed with a sign stand arrangement, such as that illustrated in FIG. 1, an operator can rest the collapsed supporting device (see FIG. 2) on the ground, and use the actuator as a foot operated release while guiding the free ends of legs 64 to their desired positions as shown in FIG. 1 . As shown in FIG. 5 b , the locking pin 106 is “bottomed out” with full travel of actuator 150 . At this extreme position, tab portion 160 is preferably maintained a spaced distance from ear portion 56 .
The drawings and the foregoing descriptions are not intended to represent the only forms of the invention in regard to the details of its construction and manner of operation. Changes in form and in the proportion of parts, as well as the substitution of equivalents, are contemplated as circumstances may suggest or render expedient; and although specific terms have been employed, they are intended in a generic and descriptive sense only and not for the purposes of limitation, the scope of the invention being delineated by the following claims. | A sign stand assembly includes a sign panel, support base and an upright mast between the two. The support base defines a locking recess and a hollow leg is pivotally connected to a plate portion and extending from the support base. A locking pin and actuator are carried within the hollow leg with the actuator including an outward protruding tab. The actuator includes a clevis portion defining an opening to receive the locking pin in interlocking engagement therewith. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to a transmitter optical subassembly and a transmitter optical module installing the same.
[0003] 2. Related Prior Art
[0004] In general, it is known, as configurations to connect a device for switching a current supplied from a current source among the semiconductor laser diode (LD) driver systems, a series configuration where switching devices are inserted in series to a light-emitting device and a shunt configuration where switching devices are inserted in parallel to a light-emitting device. A Japanese Patent application published as JP-2001-015854A discloses a typical example of series configuration. The shunt configuration has advantageous in that it uses a smaller number of devices than the series configuration and allows high-speed operation, while the shunt configuration has a drawback that the degree of modulation permitted is small and the controllability of a current is poor.
[0005] A Japanese Patent application published as JP-2004-179591A discloses another LD driver. This driver reflects the switching status of the reference current, which flows in the reference current path of the current mirror circuit, by toggling the switch connected to the reference current path, to the current supplied to the LD connected to the other current path of the current mirror circuit. In order to make steep the leading edge and the falling edge of the mirrored current supplied to the LD, a circuit is added that generates a pulse current synchronous with the leading edge and the falling edge of a signal to select the switching state. With this additional circuit, the LD driver increases/decreases the transient currents on the edges of the signal to perform high-speed LD switching.
[0006] Optical communications in recent years reaches a transmission speed exceeding 10 Gbps. In the high-speed transmission range over 10 Gbps, the frequency response of the wiring connecting a light-emitting device and a driver, that is, the transmission impedance becomes important. Especially, a waveform may be degraded by the parasitic inductance of a lead pin in a transmitter optical subassembly. Or, the leading edge or the falling edge of a signal may be delayed by a parasitic capacitance.
[0007] To solve these problems, a package with good controllability of the transmission impedance, for example, a butterfly package is used as a package for a transmitter optical subassembly. However, the butterfly package is expensive and is not effective in terms of high-speed transmission when the light emitting device is directly driven. For indirect modulation system that uses a MZ (Mach-Zender modulator) or an EA modulator (Electro-absorption modulator), the termination of a signal line may be easily and reliably carried out. For a system for directly modulating a light-emitting device, the internal resistance of the light-emitting device becomes 3 to 30 ohms in the case of a laser diode (LD). When a resistor of 1 to 40 ohms is serially inserted to the LD to terminate the transmission line, the inserted resistor and the junction capacitance of the light-emitting device constitute an integrator, which causes a problem in the high-speed transmission.
[0008] It is known, what is called, a CAN-type package as another form for the optical subassembly. The CAN-type package is less expensive than the butterfly package. A problem with the CAN-type package is that impedance matching of a lead pin is hard to ensure and the high-speed modulation is difficult. Another problem is the heat dissipation characteristic of a driver when a driver is installed within the CAN-type package. The CAN-type package has less tolerance freedom in terms of its shape and specifications including its diameter, the number of pins and LD installation method than the butterfly package. When a driver is installed within the CAN-type package, it is difficult to efficiently dissipate the heat of the driver out of the package. Large quantity of heat generated in a transmitter optical subassembly increases the temperature of the LD, which degrades the light emission characteristic and the reliability of the optical assembly.
[0009] The invention relates to a transmitter optical subassembly that may improve a high-frequency performance without increasing the power consumption of the transmitter optical subassembly and an optical data link installing the same.
SUMMARY OF THE INVENTION
[0010] An aspect of the invention relates to a transmitter optical subassembly. The transmitter optical subassembly comprises a light-emitting device including an anode electrode and a cathode electrode, a CAN-type package including a plurality of lead pins, and an auxiliary circuit. The light-emitting device and the auxiliary circuit are installed within a package and a driving signal is supplied through a lead pin. The auxiliary circuit according to the invention generates a transient current synchronous with either the leading edge or falling edge of the driving signal in the anode electrode or cathode electrode of the light-emitting device.
[0011] The transient current synchronous with the transition timing of the driving signal is supplied to a light-emitting device so that a quicker response is achieved in the light-emitting device. The auxiliary circuit includes a differentiator (low-frequency cut-off filter) for differentiating a driving signal and a transistor for generating a transient current by receiving the output of the differentiator. According to the invention, the auxiliary circuit is installed within the CAN-type package, however, current flows through the auxiliary circuit only for a short period of time while the driving signal is transmitted and thus heat generation by the current is not necessary to be considered.
[0012] Another aspect of the invention relates to a transmitter optical module. The transmitter optical module includes a driver and a transmitter optical subassembly. The driver is provided outside the transmitter optical subassembly and receives an electrical signal and outputs a driving signal. The transmitter optical subassembly includes a semiconductor laser diode, an auxiliary circuit, and a CAN-type package installing the semiconductor laser diode and the auxiliary circuit. The package has a plurality of lead pins and the driving signal is supplied to the semiconductor laser diode through one of the lead pins as well as to the auxiliary circuit. The auxiliary circuit generates a transient current in the anode electrode of the semiconductor laser diode in synchronous with the leading edge of the driving signal.
[0013] In the transmitter optical module according to the invention, a driver may be separated to a first driver and a second driver, and the output of the first driver or a first driving signal may be supplied to the anode electrode of the semiconductor laser diode installed within the transmitter optical subassembly through the first lead pin and the output of the second driver or a second driving signal may be supplied to the auxiliary circuit installed within the transmitter optical subassembly through the second lead pin. Because the first and the second drivers are used, an optimum condition can be set for each of the semiconductor laser diode and the auxiliary circuit.
[0014] In the transmitter optical module according to the invention, a current source for generating a bias current may be provided outside the transmitter optical subassembly. By supplying the first driving signal superimposed with the bias current to the anode electrode of the semiconductor laser diode, it is possible to bias the semiconductor laser diode without increasing the number of lead pins in the transmitter optical subassembly.
[0015] The first driving signal may be supplied to the cathode electrode of the semiconductor laser diode and the auxiliary circuit may bypass the current supplied to the semiconductor laser diode in synchronous with the leading edge of the second driving signal. Further, a photodiode for monitoring the optical output from the semiconductor laser diode may be installed within the transmitter optical subassembly according to the invention and the output of the photodiode may be extracted through the second lead pin for inputting the second driving signal. Any of the new features of the transmitter optical subassembly are implemented without increasing the number of lead pins.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 shows the circuit configuration of a transmitter optical subassembly and a transmitter optical module according to a first embodiment.
[0017] FIG. 2 is a time chart illustrating the features of an auxiliary circuit in the transmitter optical subassembly shown in FIG. 1 .
[0018] FIG. 3 is a circuit diagram showing a variation of the first embodiment.
[0019] FIG. 4 shows the circuit configuration of a transmitter optical subassembly and a transmitter optical module according to a second embodiment.
[0020] FIG. 5 is a circuit diagram showing a variation of the second embodiment.
[0021] FIG. 6 is a circuit diagram showing another variation of the second embodiment.
[0022] FIG. 7 is a circuit diagram showing still another variation of the second embodiment.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0023] Preferred embodiments of the transmitter optical subassembly according to the invention will be detailed referring to the drawings. In the description of drawings, the same or corresponding elements are given the same symbol and duplicated description is omitted.
First Embodiment
[0024] FIG. 1 shows the configuration of a transmitter optical subassembly 3 as a first embodiment of the invention. FIG. 1 also shows a transmitter optical module 1 having the transmitter optical subassembly 3 and converting a high-frequency driving signal input from outside to an optical signal and outputting the resulting optical signal.
[0025] The transmitter optical subassembly 3 comprises an LD (light-emitting device) 2 , a CAN-type package PKG. installing the LD 2 , and an auxiliary circuit including an n type FET 5 . The transmitter optical module 1 includes the transmitter optical subassembly 3 and a driver 4 arranged outside the package PKG.
[0026] The driver 4 receives a signal S IN input from outside the transmitter optical module 1 and outputs a driving signal S 1 . The driving signal S 1 is supplied to the cathode electrode of the LD 2 in the package of the transmitter optical subassembly 3 and the auxiliary circuit 6 through a lead pin P 1 provided in the package PKG of the transmitter optical subassembly 3 .
[0027] The auxiliary circuit 6 includes the n type FET 5 , a differentiator 9 configured with a resistor 7 and a capacitor 8 connected between the gate of the FET 5 and the input of the auxiliary circuit 6 , and a diode 10 that is connected to the source of the FET 5 and generates a self bias in the gate of the FET 5 . The drain of the FET 5 serves as the output of the auxiliary circuit 6 and is connected to the anode electrode of the LD 2 . The differentiator 9 generates a pulse signal S 3 synchronized with the leading edge and the falling edge of the signal S IN (detailed later) and its time constant is determined by the transmission rate of the signal S IN and the value of a terminator of a transmission line including the lead pin P 1 . In this embodiment, the cut-off frequency is set to approximately 8 GHz assuming that the resistor 7 is 20 Ω and the capacitor 8 is 1 pF.
[0028] Operation of the transmitter optical module 1 explained above will be described referring to FIG. 2 .
[0029] When the signal S IN is input to the driver 4 ( FIG. 2A ), the output S 1 becomes an inversion of the signal S IN . The input S 3 of the FET 5 is obtained by differentiating the signal S 1 as shown in FIG. 21 . That is, a negative and positive pulses are generated in synchronous with the leading edge and the falling edge of the output S 1 , respectively. Since the FET 5 is self-biased by the diode 10 , the drain current of the FET 5 is not influenced in the stable state except the leading edge and the falling edge of the signal S 1 and by a negative pulse from the differentiator. Only when a positive pulse is applied to the gate of the FET 5 , that is, only on the falling edge of the input signal S IN , the drain current of the FET 5 increases in the shape of a pulse ( FIG. 2C ).
[0030] For the LD 2 , the current supplied from power supply Vcc flows through the LD 2 and is sunk into the output of the driver 4 through the lead pin P 1 in response to the output of the driver 4 . In the driving, influenced by the junction capacitance of the LD 2 and the inductance of the lead pin, the waveform I LD supplied to the LD 2 shows its falling edge delayed compared with the leading edge as shown in the dotted line in FIG. 2D . In this invention, the auxiliary circuit 6 is installed within the package PKG and the auxiliary circuit is driven by the output S 1 of the driver 4 so that a drain current ID is generated in a pulse shape on the FET 5 of the auxiliary circuit 6 only on the leading edge of the output S 1 (on the falling edge of the input signal S IN ) as shown in FIG. 2C . The drain current ID bypasses a portion of the current I LD supplied from the power supply to the LD 2 . Thus, the falling edge of the current I LD supplied to the LD becomes steeper as shown by the solid line in FIG. 2D .
[0031] According to the above transmitter optical subassembly 3 and the transmitter optical module 1 , even when the falling edge of the current I LD flowing through the LD 2 is delayed due to the influence of the interconnection connecting the driver 4 and the package PKG, especially due to the inductance component at the lead pin on the anode electrode of the LD 2 and the junction capacitance of the LD 2 , a pulse current is generated on the FET 5 of the auxiliary circuit 6 and this current bypasses a portion of the current supplied to the LD 2 thereby making steeper the falling edge of the current flowing through the LD 2 . It is thus possible to obtain the high-speed configuration of the transmitter optical subassembly 3 by only installing a single active device (FET 5 ) within the package PKG. The current flowing through the FET 5 is a pulse current that occurs only at the transition of the driving signal so that the power consumption in the package PKG is not increased.
[0032] The capacitor 8 has a capacitance of a some picofarads at most and small dimensions. When the current supplied to the LD 2 is on the order of 60 mA, a small-sized FET 5 will be sufficient. The resistor in the differentiator 9 also serves as a terminator of the transmission line viewed from the output of the driver 4 so that it may be chosen to a small value of several tens of ohms, thus being less influenced by a parasitic capacitance. The influence of the parasitic capacitance is represented by a circuit parallel to the resistor so that the time constant of the parallel circuit corresponds to a much higher frequency. The auxiliary circuit 6 does not require a power source thus no additional lead pins are required.
[0033] FIG. 3 shows the configuration of a transmitter optical subassembly 13 and a transmitter optical module 1 a installing the transmitter optical subassembly 13 according to a variation of the first embodiment. The variation differs from the circuit shown in FIG. 1 in terms of the configuration of the driver 4 . This variation has a first driver 4 a and a second driver 4 b . The first driver 4 a supplies an in-phase output S 1 with the driving signal S IN to the LD 2 through a lead pin P 1 . The second driver 4 b supplies an out-phase output S 2 with the driving signal S IN to the auxiliary circuit 6 through a lead pin P 2 . The configuration of the package PKG is similar to that shown in FIG. 1 except that separate lead pins are provided respectively for the in-phase signal S 1 and the out-phase signal S 2 .
[0034] In this variation, the driving signal S 2 of the auxiliary circuit 6 and the driving signal S 2 of the LD 2 are provided separately so that the freedom to design the auxiliary circuit 6 increases. Specifically, in the auxiliary circuit 6 shown in FIG. 1 , the resistor 7 in the differentiator 9 works as a terminator of a transmission line. The transmission line also serves as a transmission line to the LD 2 . The terminator viewed from the transmission line is determined in a complex fashion by the resistor 7 , operating resistance of the LD 2 , and the input resistance of the FET 5 . The output of the driver 4 is directed to the LD 2 and the auxiliary circuit 6 . When the optimum driving conditions are not fully consistent with those of the auxiliary circuit 6 , the operation of the transmitter optical subassembly 3 could be unstable.
[0035] In this variation, it is possible to set individually optimum conditions for the LD 2 and the auxiliary circuit 6 . The load on the second driver 4 b is provided by a parallel circuit of the resistor 7 and the input resistance of the FET 5 . The input resistance is much larger than that of the resistor 7 because the input of the PET 5 is self-biased (inversely biased) by the diode 10 . Thus, the value of a terminator may be substantially determined by the resistor 7 alone. When the resistor 7 is determined, the value of the capacitor 8 is automatically determined from the value of a time constant required for the differentiator 9 . For the output transmission line of the first driver 4 a , only the LD 2 is connected. When the operating resistance of the LD 2 is below the characteristic impedance of the transmission line, it is possible to satisfy the impedance matching conditions simply by serially inserting a resistor into the LD 2 .
Second Embodiment
[0036] A second embodiment of the invention is described below.
[0037] FIG. 4 shows the configuration of a transmitter optical module 1 b including a transmitter optical subassembly 23 according to the second embodiment of the invention. The transmitter optical module 1 b according to this embodiment differs from the variation of the first embodiment in that a driver 24 a to drive an LD is a voltage-driving type,
[0038] That is, the driver 24 a receives a signal S IN and generates a voltage signal S 21 as a driving signal to drive the LD 2 . The driver 24 a is connected to the anode electrode of the LD 2 and the drain of an FET 5 through a coupling capacitor 38 and the lead pin P 1 of a CAN-type package PKG. Further, the lead pin P 1 is connected to a current source 37 for supplying a bias current 1 b to the LD 2 outside the package PKG. Same as the first embodiment, the second driver 4 b receives a driving signal S IN and supplies a signal S 2 phase-inverted from the driving signal S IN to the auxiliary circuit 6 through a lead pin P 2 . The LD 2 is connected between the lead pin P 1 and the ground in the package PKG.
[0039] In the circuit shown in FIG. 4 , the current source 37 may be connected to the anode electrode of the LD 2 through another lead pin P 3 . That is, while the output of the first driver 24 a is superimposed with the current 1 b from the current source 37 and supplied to the anode electrode of the LD 2 through the lead pin P 1 in FIG. 4 , a lead pin P 3 for supplying a bias current may be provided separately from the lead pin P 1 and the both pins may be connected together in the package PKG to supply the bias current 1 b superimposed with the signal S 21 to the anode electrode of the LD 2 . In this case, it is preferable to interpose an inductor or a resistor between the new lead pin P 3 and the anode electrode of the LD 2 in order to weaken the influence of the current source 37 on the transmission line from the first driver 24 a.
[0040] The operation of this embodiment will be described. When a signal S IN is input to the first driver 24 a and the second driver 4 b , a driving signal S 21 in-phase with the signal S IN is generated in the first driver 24 a and a signal S 2 out-phase with the signal S IN . is generated in the second driver 4 b . The signal S 21 and the signal S 2 are voltage signals. When the signal S 2 is input to the auxiliary circuit 6 , a pulse signal 33 is generated in synchronous with the leading edge and the falling edge of the signal S 2 . When the pulse signal S 3 is input to the FET 5 , a pulse-shaped drain current is generated corresponding to the pulse signal synchronized with the leading edge of the signal S 2 (equivalent to the falling edge of the signal S 21 ) because the FET 5 is self-biased by the diode 10 . As a result, same as the first embodiment, the leading edge of the supply current to the LD 2 appears faster.
[0041] As the drivers 24 a , 24 b of the transmitter optical module 1 b , a differential circuit may be used. That is, the cathode electrode of the LD 2 is grounded through a resistor or an inductor instead of the direct grounding and the in-phase output (one output) of the differential circuit is connected to the anode electrode of the LD 2 through the lead pin P 1 while the out-phase (the other output) of the differential circuit is connected to the gate of the FET 5 and the cathode electrode of the LD 2 . With this circuit configuration, it is possible to independently control the amplitudes of the in-phase output and the out-phase output of the differential circuit. This allows the control of the FET 5 of the auxiliary circuit 6 at the same time with driving of the LD 2 .
[0042] Preferable embodiments of the invention are described referring to drawings. Note that the invention is not limited to the circuits illustrated in a series of drawings but various changes can be made without departing from the spirit of the invention. FIGS. 5 to 7 show such variations.
[0043] While the transition from the lighting state to the non-lighting state is boosted by discharging the anode electrode of the LD 2 to a ground potential in the first embodiment, the transition from the lighting state to the non-lighting state is boosted by artificially bypassing the anode electrode and cathode electrode of the LD 2 in a transmitter optical subassembly 43 and a transmitter optical module 1 c according to the variation shown in FIG. 5 . In the circuit of FIG. 5 , a signal out-phase with the driving signal S IN is input to a p-FET 5 a to bypass a current flowing through the LD 2 . While the cathode electrode of the LD 2 is grounded by an inductor 11 and a driving signal is supplied to the cathode electrode of the LD 2 through a coupling capacitor 48 in FIG. 5 , the cathode electrode of the LD 2 may 5 be directly coupled to the first driver to current drive the LD 2 . This example provides a current source 47 for supplying the 5 bias current of the LD 2 outside the package PKG.
[0044] FIG. 6 is a circuit diagram showing a transmitter optical module 1 d including an optical transmitter 23 , the module providing an FET for shunt driving the LD 2 outside the package PKG according to a variation of the second embodiment. It is preferable to install within the package PKG an inductor or a resistor 39 between the anode electrode of the LD 2 and a bias current source 57 . This is to prevent the degradation of the transmission characteristic of a driving signal supplied to the LD 2 in the frequency response of the power supply Vcc.
[0045] While a driving FET is arranged outside the package PKG in this variation, the driving FET may be installed within the package. In this case, a signal lead pin may be shared by two driving systems. Specifically, a first and second drivers 54 a , 54 b are used in common and the outputs are brought into the package PKG through the lead pin P 1 . In the package PKG, one output is input to the gate of the driving FET and the other to the auxiliary circuit 6 . The FET of a differentiator 9 is self-biased by the diode 10 while the source of a driving FET 58 is grounded, so that the independent bias conditions may be also set to two FETs in this variation.
[0046] A monitor PD (photoreceptor device) for monitoring the intensity of optical output from the LD 2 may be installed within the transmitter optical package PKG. FIG. 7 is a circuit diagram of an optical module 1 e including a monitor PD 60 and an optical transmitter 63 in the example of FIG. 5 . To the wiring from the lead pin P 2 connected to the gate terminal (input terminal) of the FET in the auxiliary circuit 6 a is connected the anode electrode of the PD 60 . Also, to the lead pin P 2 is connected the output of the second driver 64 b through ED the coupling capacitor 69 and an APC circuit 70 for detecting the monitor current output from the PD 60 .
[0047] With this configuration, the lead pin P 2 is simultaneously applicable to more than one usage, that is, to the output of a monitor current from the PD 60 and to a signal to a differentiator 9 thus implementing a new feature without increasing the number of lead pins. The monitor PD 60 is used to control the average optical output power of the LD 2 and its operational speed is sufficiently lower than the transmission rates which eliminates the interference to the transmission signal.
[0048] Further, it is possible to provide a transistor for generating a pulse signal synchronized with the leading edge of the supplied current to the LD 2 such as the FET 5 a in the auxiliary circuits 6 , 6 a , in place of a transistor for generating a pulse current synchronized with the falling edge of the supplied current to the LD 2 , or in addition to such a transistor. | To provide a transmitter optical subassembly that provides an enhanced high-frequency response without increasing the power consumption within a CAN-type package. The transmitter optical subassembly includes a semiconductor laser diode, an auxiliary circuit, and a package for installing the semiconductor laser diode and the auxiliary circuit. The auxiliary circuit generates a transient signal synchronized with the leading edge or falling edge of a driving signal for the semiconductor laser diode in an electrode of the semiconductor laser diode for a very short period in order to boost the response speed of the semiconductor laser diode. The auxiliary circuit operated intermittently so that it is not necessary to consider heat caused by the auxiliary circuit even in case the auxiliary circuit is installed in the package. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to materials handling, and more particularly to unloading dry bulk materials from the holds of ships.
2. Description of the Prior Art
Increasing concern over the environment has spurred numerous laws regulating the manner and extent to which industrial processes may affect the environment. Particularly with regard to materials handling apparatus and processes, this has meant tighter restrictions on the amount of material which can be released into the atmosphere. Efficiently meeting, and better still exceeding, these standards has been especially difficult in the maritime setting where dry bulk materials must be unloaded from the holds of ships. Processes and apparatus which might work well on shore are often too expensive or unworkable in the maritime setting.
The transitory nature of the cargo ships at the dock makes it difficult to use bulk transfer processes and apparatus which are successful on land. In some cases it would be necessary to modify each and every ship to accomodate a particular new process. In other cases it might be necessary to modify the process to accomodate different ship designs. The huge amounts of material which are moved can also be a significant impediment. It is not uncommon for each hold of a ship handling cement, for example, to carry eleven thousand tons of the material. Many processes which might otherwise be suitable are not capable of handling large quantities of materials such as this.
Bulk materials handling in the maritime setting is almost always an open-air process. Each ship hold is unloaded through an opened main hatch in the deck of the ship. Conveyors, conduits and the like necessary for continuous unloading processes are set down into, and extend out from, the hold through the opened main hatch. In the event of a rainstorm, sudden winds or the like, the hatch cannot be easily closed. If the bulk material can be damaged by water, as with cement, extensive damage can result.
Materials handling is an old and varied art. Hoppers, conveyors, buckets, conduits and the like, of many shapes and sizes, have been used to move bulk materials from one place to another. This equipment, however, often does not meet often newer and stricter environmental standards when used in conventional processes. It would desirable to provide a process and apparatus which would move bulk materials from the holds of ships to on-shore collection stations in a manner which meets or even exceeds environmental standards. It would also be desirable if the system would operate on many ship designs and with no modification necessary to existing ships. The crews on ships are typically responsible for unloading. It would therefore be desirable if the process of unloading did not require the extensive development of new skills such that crews uneducated in the workings of the process and apparatus would have difficulty in unloading the cargo.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a process and apparatus for transporting bulk material from the holds of ships in a manner which meets or exceeds environmental standards.
It is another object of the invention to provide a bulk transfer process and apparatus which may operate on many ship designs and with little or no necessary modification to the ship.
It is yet another object of the invention to provide a bulk transfer process and apparatus for unloading ships which can be readily learned by crews uneducated in the workings of the process.
It is still another object of the invention to provide a bulk transfer process and apparatus for unloading ships which allows the main hatch of the ship to be rapidly closed in the event of a rainstorm or other sudden adverse conditions.
These and other objects are accomplished by a method and apparatus for cleanly unloading dry bulk material carried by ships in below deck holds. A plurality of the holds are filled with the material and at least one of the holds is empty. A portable open-topped, intermediate collection station is disposed in the at least one empty hold. Loads of the material are moved in at least one closed receptacle from the filled holds to the open-topped, intermediate collection station in the at least one empty hold. Airborne dust is continuously collected at a dust collecting station from over the collection station to prevent local formation of a dust cloud. The dry bulk material is then transferred from the intermediate collection station through closed conduit means to an on-shore collection station. Exposure of the dry material to conditions likely to cause dust clouds and likely to result in wetting of the material is thereby minimized.
The dry bulk material is preferably transferred from the intermediate collection station to the on-shore collection station along a path passing through an opening in the deck of the ship, such that the at least one empty hold can be covered without interrupting the transferring step.
The intermediate collection station is preferably provided as an open-topped hopper. Pneumatic means are provided for collecting the airborne dust at the dust collecting station. The pneumatic means preferably comprises suction ports disposed about the periphery of the top of the hopper. Vacuum applied to the suction ports draws the airborne dust into a collection conduit disposed about the periphery of the top of the portable collection station.
Means are provided for pumping the material out of the hopper. Preferably, the dry bulk material is pneumatically pumped from the intermediate collection station to the on-shore collection station.
The dry bulk material is moved from the filled holds to the portable collection station in at least one clam shell bucket. The clam shell bucket is substantially closed during movement and preferably has a closed top cover portion to prevent releasing airborne dust during movement. The clam shell bucket is preferably operated by a ship-mounted crane.
The airborne dust drawn through the suction ports is preferably filtered on board ship. This can be accomplished by suitable means including the traditional bag house filter design. The filter bags are preferably mechanically or pneumatically shaken periodically to release the collected dust.
The open-topped hopper can be conveniently mounted in a portable framework adapted to be lifted into and out of the operative position in the at least one empty hold. The framework may be provided as a monolithic structure, or may be provided as plural structures which may be detachably interconnected by suitable means such as dowels.
The dust collecting station is operatively connected to the suction means but can be located remotely therefrom. The dust collecting station is also locatable remotely from the framework.
BRIEF DESCRIPTION OF THE DRAWINGS
There are shown in the drawings forms and embodiments which are presently preferred it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown, wherein:
FIG. 1 is a perspective, partially broken away, of a ship being unloaded according to the invention.
FIG. 2 is a cross section through the beam of the ship according to the line 2--2 in FIG. 1.
FIG. 3 is a cross section through the length of the ship according to the line 3--3 in FIG. 2.
FIG. 4 is a cross section through a hopper of the invention as indicated by the line 4--4 in FIG. 3.
FIG. 5 is an exploded perspective of framework connecting structure according to the invention.
FIG. 6 is a side elevation of framework connecting structure according to the invention.
FIG. 7 is a cross section of the framework connecting structure of FIG. 6 according to the line 7--7 in FIG. 6.
FIG. 8 is a cross section of alternative framework connecting structure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Apparatus
Cargo ships used to carry dry bulk materials typically have a plurality of holds. These holds may nevertheless be quite large. A ship carrying cement, for example, may carry eleven thousand tons or more in a single hold. A ship's carrying capacity usually requires that at least one hold be left empty due to the weight of heavy bulk materials. Cargo ships also typically have a mobile crane which typically unloads cargo from the holds of the ship to on-shore receptacles or conveyors. The present invention takes advantage of these facts while providing an environmentally sound method and apparatus for unloading dry bulk materials from ships.
Referring now to FIG. 1, a cargo ship 10 has a plurality of cargo holds including a hold 12 filled with cement which is to be unloaded and transported to on-shore collection stations such as silos 14-16. The ship will usually be outfitted with a crane 20 which is commonly mounted on a base 22 so as to be pivotable about its vertical axis. The ship's crane 20 typically has a clam shell bucket 23 suspended from a boom 24 by an operating cable 25. The ship's crane 20 is typically made movable relative to the plurality of holds by suitable structure including rails 26, 28 along which the base 22 of the crane may be moved by a suitable driving motor. The ship's crane 20 may thereby be positioned properly for the hold which is being unloaded.
A hold 30 with a main hatch opening 32 is empty as required by the carrying capacity of the ship. A hopper 36 is provided in the empty hold 30. The hopper 36 serves to collect the dry bulk material and preferably is cyclone-shaped with a substantially V-shaped cross section (FIGS. 2-3). A large diameter inlet 40 is provided at the top of the hopper and a small diameter outlet 42 smaller in diameter than the large diameter inlet 40 is provided at the bottom of the hopper. The upwardly increasing cross-sectional area of the hopper slows the upward flow of air and dust when dry bulk materials are dropped into it and thereby helps to prevent the formation and escape of dust clouds. A lump grate can be positioned in the hopper to screen out large solid chunks of material which might otherwise clog the system.
The hopper need not be of any particular set of dimensions. It is advisable for efficient unloading that the hopper have a capacity to hold such a quantity of materials that material may be continuously fed to the transfer apparatus notwithstanding the discontinuous transfer of material to the hopper by the ship's crane 20. An eighty ton capacity is desirable, for example, where cement is unloaded, and accordingly may have an inlet with an inside diameter of 24' or more. A cone shaped hopper has been found to be particularly useful. The cone angle should provide sufficient divergence to slow the upward flow of air and dust. The cone should not be so flat, however, as to retard the downward flow of cement. It has been found that the included cone angle (from side to side) preferably should not exceed 65 degrees from the cone axis, and would preferably not be less than 55 degrees. The large diameter inlet 40 of the hopper should be wide enough to allow the clam shell bucket 23 to open within the hopper. The bucket then acts as a lid over the hopper to reduce dust cloud formation when material is dropped into the hopper.
The hopper 36 preferably has associated with its inlet 40 structure for applying a vacuum to the area of the inlet 40 and above and below it. Suitable vacuum structure would preferably include a plurality of openings 50 around the inside rim of the inlet 40 of the hopper (FIG. 4). The dimensions of the openings 50 are preferably adjustable to permit adjustment of the flow rates therethrough. This can be accomplished by the provision closure means which can include plates 53 slidably or pivotably mounted at the openings 50. The closure means will preferably permit at least a 3:1 adjustment in the area of each opening 50, as from a one and one-half inch effective diameter to a one-half inch effective diameter. The openings 50 connect to manifold 54 through which the vacuum is applied. The manifold 54 is connected, as by vacuum conduit 55, to a vacuum source 60 which supplies a suitable vacuum to the inlet 40 of the hopper 36. The manifold 54 is preferably constructed so that it has a greater cross-sectional area adjacent the vacuum conduit 55 to accommodate the greater volumetric flow rates that are present in this portion of the manifold owing to the many upstream openings 55. This allows the velocity of the air stream through the manifold 54 to be kept substantially the same despite the large differences in volumetric flow rates in different parts of the manifold 54. Excessive velocity will cause unnecessary energy losses, and insufficient velocity will allow the dust to settle.
The vacuum source 60 preferably includes a filtration unit to remove the particulate matter from the airstream, although the filtration unit may, of course, be provided separately from the vacuum source. A suitable filtration unit may be selected from numerous units available for this purpose. A preferable filtration unit would be of the "bag house" design. The bag house, as is known in the art, has a plurality of filter bags through which the air stream is drawn and where the particulate contaminants are caught by the filter material. The bag house used in the present example might have one hundred forty-four filter bags. Each bag is generally tubular in shape and may have a diameter of approximately 1/2 foot and a length of approximately 12 feet. The vacuum source 60 draws air through the openings 50 at the inlet 40 of the hopper, through the vacuum 55 conduit, and then through the bag house so that particulate matter is filtered through the filter bags.
The vacuum source 60 is sized for the size of the hopper 36, its inlet 40, as well as for the particular material being handled and its flow rate. The vacuum source for the 24' diameter hopper described above would draw approximately twenty thousand cubic feet per minute of air through the manifold 54 and the bag house. This would preferably correspond to a capture velocity of approximately 50-100 ft/min at the openings 50, a velocity range in which good dust capture has been obtained. It is desirable to keep the air velocity through the manifold 54 and vacuum conduit 55 to the filtration unit around or above 4000 ft/min to keep the cement dust from settling. Velocities much above about 6000 ft/min result in large energy losses. Velocities would preferably be between about 3000 ft/min and about 7000 ft/min.
Filtration eventually causes the filter bags to become clogged with the filtered particulate matter and it may be necessary to periodically clear the bags to regain efficient filtration. This may be accomplished by several methods, including air pulses and mechanical shaking. If pulses of air are used, an airstream of perhaps 100 psig would be blown onto the filter bags in a direction opposite to that of the flow of the filtered stream. The particulate matter is blown from the filter material and falls to a collector beneath the bag house. The collector is periodically emptied. The collector may be emptied manually, or structure may be provided to remove the collected particulate matter.
A framework is preferably used to support the hopper and may be constructed in a variety of designs and from a variety of materials. An adequate framework must support the hopper and the substantial weight of material which can be in the hopper, sometimes weighing more than eighty tons. The framework should be dimensioned such that the top of the hopper 36 is not near the main hatch 32 of the hold 30. This will prevent released dust from escaping from the hold, and allow the hold to act essentially as a settling chamber for the dust. The framework can be provided as a single, integral unit. Alternatively, the framework may be provided in pieces which are fastened together in the hold of the ship. It should be recalled that the hopper may be dimensioned to hold more than eighty tons of cement and that this large scale structure must be lifted into the hold by the ship's crane. It is desirable to break-up the structure into readily assembled, lighter weight portions which are more easily installed. The framework shown in the drawing has two halves consisting of an upper half 64 and a lower half 68. The lower half 68 would be placed in the hold first, resting on the floor of the hold. The upper half 64 preferably has the hopper 36 fastened thereto. The upper half would be placed over the lower half and the two would be fastened together by suitable fastening structure. In this way the framework and hopper are more easily moved into and out of the hold to provide a more portable system.
Framework pieces can be fastened together by means known in the art for this purpose. One suitable structure is the dowel-aperture arrangement shown in FIGS. 5-7. Abutting flange portions 81 and 83 on framework pieces 84 and 90, respectively, provide a secure contact surface for the joint. Dowel portion 82 on flange portion 81 snugly mates with aperture portion 86 on flange portion 83 to secure the joint together. The weight of the materials in the hopper 36 vertically secures the abutting ends of the upper framework half 64 to the lower framework half 68.
Several framework pieces can be difficult to secure together by two-directional fastening structure such as dowels. It is therefore within the scope of the invention to secure framework pieces together by three-directional fastening structure as shown in FIG. 8. Framework pieces 94 and 98 with abutting flange portions 100 and 104, respectively, are secured together by suitable fastening means such as bolts 110 and nuts 112.
Pump means 120 is provided to move the bulk material out of the hopper. The pump means may be selected from a variety of pumps known for this purpose. The pump should be capable of moving very large amounts of dry bulk material. A preferabe pump would be capable of moving at least two hundred twenty tons per hour of a dry bulk material such as cement. Suitable pumps might include those known as "H" pumps and "M" pumps. The pump is preferably fed dry bulk material through an attachment to the small diameter outlet 42 of the hopper. This can be accomplished by a flexible plenum and a rotary air lock feeder. The pumps should be of suitable construction so as to be relatively portable, that is, able to be lifted into and out of a ship's hold. The pump would preferably have auger means driven by a motor means to move the cement or other dry bulk material to a contact zone. Alternatively, an air pump could be used in place of the auger means, as would be apparent to one skilled in the art. An airstream supplied by one or more compressors through an airstream supply conduit 122 is blown through a series of jets to the contact zone where the airstream contacts the dry bulk material. The dry bulk material is carried by the airstream through a closed outlet conduit 126 out of the hold of the ship and into on-shore storage receptacles 14-16.
A rotary air lock feeder preferably seals the inlet of the pump means 120 from the outlet 42 of the hopper. This is commonly accomplished by a plurality of vanes rotating in a closed housing which accept material at one point of rotation through an inlet opening in the housing and discharge the material into the pump at another point of rotation through a discharge opening in the housing. The point of rotation receiving material is sealed by intermediate vanes against substantial gas or material contact with the point of rotation discharging material into the pump.
Compressors supply a large volume of low pressure air or other suitable fluid to move the bulk material through the outlet conduit 126 and into the on-shore collection receptacles 14-16. The compressors preferably are capable of delivering about fifteen hundred cubic feet per minute of about 30 psig air where cement is to be transported. The compressors may be selected from a number of models and designs suitable for this purpose. The compressors may be located on-shore as in compressor station 130 (FIG. 1, compressors not shown). A permanent on-shore airstream supply conduit 132 running from the compressor storage facility 130 to dockside may be buried within the dock for convenience. The on-shore airstream supply conduit 132 would then be connected to the on-board airstream supply conduit 122 as at juncture 140 during installation. Similarly, a permanent on-shore outlet conduit 142 leading from dockside to the on-shore storage receptacles 14-16 may be buried within the dock. The on-shore outlet conduit 142 would be connected to the on-board outlet conduit 126 at dockside as at juncture 144.
Each separable component of the process and apparatus of the invention preferably weights less than fifteen tons. This allows the components to be lifted by conventional ship's cranes into the hold or onto the deck of the ship as the case may require. It would of course be possible to use larger equipment if the ship's crane can accommodate the weight.
INSTALLATION
Installation of the equipment in preparation for unloading the dry bulk material begins with placement into the hold of the airstream supply conduit 122 from the compressors and the outlet conduit 126 loading to the on-shore storage receptacles 14-16. Connections 140 and 144 to any on-shore conduit systems may be made as necessary. The airstream supply conduit 122 is directed up the side of the ship and into empty ship's hold 30. The airstream supply conduit 122 can be simply draped over the side of the main hatch into the hold. It is preferable, however, to insert the conduit through a smaller hatch of the ship leading into the hold. Most ships have at least one small manhole or the like leading into each hold in addition to the main hatch. It has been found that insertion of conduits and any other necessary lines, such as power lines, are conveniently placed into the hold through one of these smaller hatches. The main hatch may then be readily closed in the event of sudden adverse conditions such as high wind gusts or rain with minimal damage to the cement or other dry bulk material below.
The ship's crane 20 is used according to the invention to lift the necessary equipment into an empty hold. Accordingly, the crane lifts the pump means 120 into the hold 130 and sets it on the floor preferably at or near the center of the hold 130. The airstream supply conduit 122 and the outlet conduit 126 may then be connected to the pump means 120.
The framework is then preferably assembled. The framework may be constructed to set over the pump means 120 as shown in FIGS. 2-3. The hopper 36 may be attached to the framework, which supports the hopper over the pump at the proper height. A preferable method of installing the framework would provide a lower framework portion 68 and an upper framework portion 64. The hopper 36 would be secured to the upper framework portion 64. The lower framework portion 68 would be set in place over the pump, after which the upper framework portion 64, with the hopper 36, would be set in place on the lower framework portion 68. The two portions may be secured together by aligned aperture portions 86 and dowel portions 82 which snugly interfit to hold the framework together. The hopper 36 is positioned with its outlet 42 directly above the inlet to the pump, with the rotary air lock feeder positioned therebetween. The hopper is bolted to the top of the pump.
The vacuum source 60 may be set in place alongside the hopper/framework on the floor of the hold. Alternatively, the source 60 may be set on the deck of the ship. The vacuum conduit 55 is connected between the vacuum manifold 54 and the vacuum source 60. The outlet conduit 126 is preferably then hooked up to the pump means 120.
Electrical connections are made to the filtration unit and the pump means to supply the motors. The electrical equipment is preferably hooked to a starter set on the deck of the ship which supplies a power boost if necessary and provides a centralized on/off switch. The starter unit should be capable of supplying 300 amps. The electrical connections are then hooked to suitable connections on-shore.
The installation process described above can be performed in relatively short periods of time notwithstanding the size of the equipment being handled. It is desirable to have shore connections hooked up before the installation of the equipment to minimize installation time once the ship is ready for unloading.
OPERATION
In operation the ship's crane is used with a clam shell bucket 23 to lift material out of the cargo holds and place it into the hopper 36 resting in the empty hold 30. The clam shell bucket 23 should be closed topped to minimize dust formation during transport from the hold to the hopper 36. Also, the clam shell 23 should be opened within the hopper 36 to release the material into the hopper. The clam shell acts as a hood to the hopper 36 and with the hopper 36 traps and impedes dust cloud formation.
The shape of the hopper can help to slow the upward movement of dust. A hopper which is substantially conical in shape, or which has an increased cross sectional area at its top as opposed to its bottom, acts to slow the upward movement of air which would carry a dust cloud out of the hopper. Dust which nonetheless reaches the upper opening of the hopper is drawn by the vacuum created through the openings 50. This dust is carried through the vacuum conduit 55 to the filter unit, as at the vacuum source 60. In the filter unit the dust may be collected in filter bags. The filter bags may be periodically shaken or pulsed with an airstream to clear the filter bags. The removed dust particles fall into the collector where they can be manually or mechanically removed.
Some particulate matter may still escape from the large diameter inlet 40 of the hopper 36. This material is substantially prevented from reaching the atmosphere by the positioning of the hopper within the empty hold 30. The large diameter opening 40 is positioned well below the main hatch 32 of the hold 30. The large, empty hold represents a very large volume of essentially stagnant air removed from the atmospheric wind, and acts as a settling chamber for the escaped dust. Dust particles which escape from the hopper 36 encounter this stagnant air and settle to the bottom of the hold 30 where they can be collected and removed.
The dry bulk material passes through the small diameter outlet 42 of the hopper, preferably through a rotary air lock feeder, into the pump means 120. The pump moves the material by the action of an auger or by air pressure into contact with an airstream supplied by the airstream supply conduit 122. The air flows through a series of jets and contacts the material, carrying it out through the discharge conduit 126. The material travels through the discharge conduit system to the on-shore storage receptacles 14-16. Dust which has settled on the floor of the hold 30 can be swept and removed periodically.
The invention provides a means for unloading dry bulk material from ships which combines portability, speed, and environmental safety. Each of the components necessary to practice the invention can weigh under fifteen tons, and can thus be lifted into and out of the ship's hold by the ship's crane. The parts are readily assembled notwithstanding their large size. Installation is straightforward and readily accomplished by relatively few workmen. The invention takes advantage of the fact that one or more holds are commonly left empty when transporting heavy dry bulk materials. Moreover, because the components according to the invention are portable, no permanent modifications to a ship's hold are necessary to practice the invention. When the ship has been unloaded, it may immediately be loaded with another material and put directly back into service. Since all supply lines according to the invention are preferably inserted through small hatches in the deck, in the event of rain the main hatch can be closed and the material does not suffer substantial damage. The invention has been described primarily for use in unloading cement, although it would be apparent that the invention is similarly suitable for other dry bulk materials such as grain or coal. Unloading according to the invention is equal in speed according to conventional processes. Strict environmental standards are maintained according to the invention.
This invention can be embodied in other forms without departing from the spirit or essential attributes thereof, and accordingly, reference should be made to the appended claims rather than to the foregoing specification as indicating the scope thereof. | A method for cleanly unloading dry bulk material carried by ships in below-deck holds is disclosed. The method includes the steps of disposing a portable open-topped, intermediate collection station in at least one empty hold of a ship. Loads of material in at least one filled hold are moved in at least one receptacle to the open-topped, intermediate collection station in the at least one empty hold. Airborne dust is continuously collected from over the intermediate collection station to prevent local formation of a dust cloud. The material is transferred from the intermediate collection station through closed conduit structure to an on-shore collection station. Exposure of the drying material to conditions likely to cause dust clouds and likely to result in wetting of the material is minimized. Apparatus for use in cleanly unloading dry bulk material from the holds of a ship includes an open-topped hopper adapted to be lifted into and out of an operative position in the at least one empty hold. Suction apparatus disposed about the periphery of the top of the hopper draws material out of the air above the hopper to prevent formation of a dust cloud. Structure at the outlet of the hopper pumps the material from the hopper through a closed conduit to an on-shore collection station. | 1 |
This application is a continuation of application Ser. No. 07/347,643 filed May 5, 1989 now abandoned.
BACKGROUND OF THE INVENTION
Field of Invention
The present invention relates to a shakeproof bearing using a high damping elastomer made of butyl rubber, NBR or the like as an energy absorber (hereinafter called a damper).
SUMMARY OF THE INVENTION
The following structure has been hitherto known as a shakeproof bearing for protecting a superstructure such as a building from destructive force of earthquake by slidably supporting this superstructure on a substructure such as its foundation in the horizontal direction, and reducing the input acceleration of the earthquake.
What is shown in FIG. 9 is a shakeproof bearing alternately laminating a hard plate 1 such as steel plate, and a rubber-like elastic plate 2 low in compression set. This shakeproof bearing 3 has an extremely large ratio of the modulus of elasticity in the vertical direction to the modulus of elasticity in the horizontal direction, and it can support the building slidably in the horizontal direction while keeping stable in the perpendicular direction. Moreover, the natural oscillation period of the building is made longer than the period of the maximum amplitude component of the earthquake, so that the acceleration response of the building when struck by an earthquake can be reduced. This shakeproof bearing itself has hardly any capacity for absorbing vibration energy during aseismic action, it is necessary to be furnished with a damper for absorbing energy.
However, because of this damper, the space of the entire device becomes large, and the number of points of action of force increases, and the design becomes complicated, or the installation cost becomes high. Besides, in the plastic dampers such as steel bar dampers mainly used hitherto, deterioration by use was quick, and it was necessary to replace after a certain period of use.
Accordingly, as a one-piece structure containing the damper, the shakeproof bearings as shown in FIG. 10 to FIG. 12 were devised.
FIG. 10 shows a shakeproof bearing having a lead plug 4 placed in the middle of the shakeproof bearing 3 shown in FIG. 9 as a damper to absorb energy (Japanese Patent Publication 61-17984).
However, because of this lead plug 4, after deformation, the superstruture is hard to return to the original position, and the initial stiffness is too high so that the small vibrations are directly transmitted to the superstructure, thereby leading to new problems.
What is shown in FIG. 11 is a shakeproof bearing intended to eliminate the defects of the lead plug 4 by using a high damping elastomer 5 possessing an action for absorbing vibration energy for the rubber-like elastic plates in the shakeproof bearing 3 explained in FIG. 9 (Japanese Laid-Open Patent 62-83139).
In this shakeproof bearing 6, however, since the high damping elastomer 5 directly supports the large vertical load of the superstructure, the creep amount is large, and the internal strain increases, and the durability (life) is poor.
The shakeproof bearing 8 shown in FIG. 12 is designed so that the high damping elastomer may not directly support the large vertical load of the superstructure. In this structure, a penetration hole is opened in the vertical direction in the middle of the shakeproof bearing 3 in FIG. 9, and a high damping elastomer 7 is inserted in this penetration hole so as to absorb the vibration energy (Japanese Laid-Open Utility Model 61-39705).
The shakeproof bearing 8 shown in FIG. 12 appears to support the vertical load only by the laminated portion of hard plate 1 such as steel plate and rubber-like elastic plate 2. Actually, however, the high damping elastomer 7 also supports the vertical load substantially. This is explained below. When loaded in the vertical direction, the rubber-like elastic plate 2 is compressed, and, same as a strain occurs, the internal high damping elastomer 7 is compressed and bulges out in the horizontal direction. Its circumference is confined by the hard plate 1 and rubber-like elastic plate 2. As a result, the high damping elastomer 7, same as the rubber-like elastic plate 2, supports the vertical load. Therefore, when an elastomer having a large creep amount is used inside, the creep strain of the entire bearing increases. The high damping elastomer generates, by nature, a large creep strain. Accordingly, although the creep amount of the shakeproof bearing 8 shown in FIG. 12 is small as compared with that of the shakeproof bearing 6 shown in FIG. 11, it is larger as compared with that of the shakeproof bearing 3 made of an elastomer small in damping as shown in FIG. 9. Hence, the durability is impaired by the internal strain due to creep.
It is hence a primary object of the invention to present a shakeproof bearing small in vertical creep deformation in a shakeproof bearing using a high damping elastomer as a damper.
To achieve the above object, this invention presents a shakeproof bearing characterized by disposing a high damping elastomer on the circumference of a bearing body the high damping elastomer being formed by alternately laminating a hard plate possessing stiffness and a rubber-like elastic plate low in compression set.
The high damping elastomer may be also presented as a laminate formed by alternately laminating and adhering a hard plate possessing stiffness and a plate-shaped high damping elastomer.
The high damping elastomer in the shakeproof bearing of the invention is disposed on the outer circumference of the bearing body subjected to vertical load, and is free to bulge out to the deformation stress due to external force when struck by an earthquake. Accordingly, it is free from vertical load, and creep is not generated, and hence the life is long.
When the high damping elastomer is formed as a laminate containing a hard plate therein, the movement of the high damping elastomer in the vertical direction is defined, and the amount of strain per unit volume to the vibration in the horizontal direction increases. Accordingly, as compared with the structure without lamination, the damping constant can be increased.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing an embodiment of a shakeproof bearing of the invention;
FIG. 2 is a sectional view showing a practical manufacturing example of the shakeproof bearing shown in FIG. 1;
FIG. 3 is a diagram showing the hysteresis loop for exaplaining the damping constant in a high damping elastomer;
FIG. 4 is a sectional view showing a practical manufacturing example of a shakeproof bearing of the invention by using a laminated high damping elastomer;
FIG. 5 is a sectional view showing a structure example for mounting the high damping elastomer;
FIG. 6 is a drawing for explaining the structure for mounting the high damping elastomer on the bearing body by dividing;
FIG. 7 is a sectional view showing a shakeproof bearing having a high damping elastomer installed internally at a clearance, as a reference example to be compared with the invention;
FIG. 8 is a sectional view for explaining the fire test conducted on the shakeproof bearing of the invention; and
FIG. 9 to FIG. 12 are sectional views showing different structural examples of conventional shakeproof bearings.
DETAILED DESCRIPTION OF THE INVENTION
A basic structure of the shakeproof bearing 10 of the invention is shown in FIG. 1. This shakeproof bearing 10 is composed by forming a columnar bearing body 13 by alternately laminating a rubber-like elastic plate 11 low in compression set, such as natural rubber, and a hard plate 12, such as steel plate, with its circumference surrounded by a high damping elastomer 14. Between this high damping elastomer 14 and the bearing body 13, although it is not necessary to provide a gap, it is better not to adhere with each other. If the damping capacity of the rubber-like elastic plate 11 low in compression set is high or low, it may be adjusted by varying the quantity or performance of the externally mounted high damping elastomer 14.
As the rubber-like elastic body 11 low in compression set such as natural rubber, it means an elastomer of which compression set is 25% or less. The high damping elastomer 14 refers to a material of which tan δ is 0.15 to 1.5 at the time of 25° C., 0.5 Hz, ±50% shearing strain, and absolute value of complex modulus |G*| of 2 to 21 kgf/cm 2 at this time.
This absolute value of complex modulus |G*| is the absolute value of the complex modulus G*, that is, ##EQU1## where G 1 is a storage modulus, which is the quotient of the amplitude τo·cos δ in phase with the strain of stress divided by the strain amplitude γo, and G 2 is a loss modulus, which is the quotient of the amplutude τo·sin δ of the component differing in phase by 90° from the strain of the stress divided by the strain amplitude γo. Practical examples of this high damping elastomer may include butyl rubber, NBR polynorbornene etc. and also include elastomer mixtures high in damping obtained by adding reinforcing agent, filler, resins, softening agents or the like to NR, SBR, BR, polynorbornene, silicone rubber, fluororubber, chlorobutyl rubber, chloroprene rubber, urethane elastomer, or their blends.
A practical example of fabrication of the basic structure in FIG. 1 is explained below while referring to FIG. 2.
In the shakeproof bearing 10a shown in FIG. 2, a columnar bearing body 13 is formed by using 39 pieces of natural rubber measuring 600 mm in diameter R and 4 mm in thickness as rubber-like elastic plate 11, and 38 steel plates of 2 mm in thickness as the hard plate 12 sandwiched by natural rubber. The high damping elastomer 14 disposed concentrically around this bearing body 13 is cylindrical, measuring 620 mm in inside diameter, and 880 mm in outside diameter. The high damping elastomer 14 is made of polynorbonen of which tan δ is 0.53 at the time of 25° C., 0.5 Hz, ±50% shearing strain, and absolute value of complex modulus |G*| of 7 kgf/cm 2 at this time. Flanges 15 of high strength are affixed to the upper and lower surfaces of the bearing body 13 and high damping elastomer 14. In this particular example, the adjoining elastic plate 11 and steel plate 12 are bonded together, although they need not be done so necessarily.
In this fabrication example, when the damping constant h in shearing deformation was measured, it was 0.12. Usually, the damping constant h of shakeproof bearing is sufficient at 0.1 to 0.15, and therefore this value of 0.12 is a sufficient value. Incidentally, the damping constant h is a value for expressing the vibration damping performance such as vibration, and it is expressed in the formula ##EQU2## where ΔW is the energy consumed in every period of vibration, and W is the input elastic energy. When this relation is explained by the displacement in the horizontal direction and the hysteresis loop 16 plotted by its reaction in FIG. 3, ΔW is the area enclosed by the hysteresis loop 16, and W is the area of the shaded portion.
The high damping elastomer 14 of this invention may not be necessarily a single piece as shown in FIG. 1 and FIG. 2. It is enough as far as the high damping elastomer 14 is disposed around the bearing body 13 in a state capable of deforming in the horizontal direciton due to vibration during aseismic action. For example, when this high damping elastomer is made of a laminate, the damping constant may be much increased. Its practical example of fabrication is explained by referring to FIG. 4.
In the shakeproof bearing 10b shown in FIG. 4, the portion of the high damping elastomer 14 of the shakeproof bearing 10a shown in FIG. 2 is laminated, while the other portions are same as the shakeproof bearing 10a shown in FIG. 2 in materials, dimensions, and shades. The laminate 14a of this high damping elastomer is composed of 20 high damping elastomer plates 17 of 7.8 mm in thickness, being laminated with 4 mm thick steel plates 18 alternately as hard plates. The overall dimensions of the laminate 14a are same as those of the high damping elastomer 14 shown in FIG. 2, that is, cylindrical measuring 620 mm in inside diameter and 880 mm in outside diameter. The material of the high damping elastomer plates 17 is also same as the high damping elastomer 14 shown in FIG. 2, that is, polynorbornene having tan δ of 0.53 at the time of 25° C., 0.5 Hz, ±50% shearing stress, and absolute value of complex modulus of 7 kgf/cm 2 at this time. As the hard plates 18, steel plates or the like may be used, but in order to enhance the fireproof performance, it is preferable to use nonflammable or flame-retardant materials low in thermal conductivity.
In this fabrication example, it is necessary to adhere the layers of the laminate 14a of the high damping elastomer. As previously described, the layers in the bearing body 13 are, while not necessarily, bonded together. This is because the layers are naturally adhered when subjected to a large vertical load.
When the damping constant of the shakeproof bearing 10b shown in FIG. 4 in shearing deformation was measured, it was 0.14. It is larger than the value of the shakeproof bearing 10a in FIG. 2.
Incidentally, it is desired to affix the high damping elastomer 14 or laminate 14a to upper and lower flanges 15 by using mounting plates 19, 19, for example, valcanized and adhered to the upper and lower surfaces thereof as shown in FIG. 5. It is because the damping action is exhibited more easily when directly exposed to the relative dislocation of the superstructure and substructure.
Meanwhile, at least one cut 20 may be provided in the high damping elastomer 14 or its laminate 14a. By this split structure, it is possible to install in an existing shakeproof bearing. This structure is realized because the high damping elastomer 14 or its laminate 14a is mounted externally, and aside from the case of internal disposition of the high damping elastomer, it is possible to install a high damping elastomer having a different outside diameter even afterwards. Therefore, the damping performance of the shakeproof bearing may be varied later. It is also easy to manufacture the laminated portion because it can be made independently of the high damping elastomer.
It is by the concept of providing the high damping elastomer with a permissible space for bulging out that the high damping elastomer 14 or its laminate 14a is disposed outside the bearing body 13 in this invention. This concept may be considered to be applied to the shakeproof bearing 8 shown in FIG. 12 as prior art so as to make the inside of the bearing body 8 larger than the outside diameter of the high damping elastomer 7 as shown in FIG. 7. But when the high damping elastomer 7 is installed internally as in this example the free surface of the laminated portion of the rubber-like elastic plate and hard plate is formed also at the inner side, and therefore the vertical stiffness of the bearing body 8a is significantly decreased. Consequently, in order to obtain a necessary vertical stiffness, the sectional area of the laminated bearing body 8a must be increased, and as a result the outside diameter of the shakeproof bearing becomes too large to be practical.
Besides, in the shakeproof bearing of the invention, as a result of disposition of high damping elastomer 14 or its laminate 14a around the bearing body 13, it is simultaneously provided with a fireproof performance, that is, the function of protecting the bearing body supporting the weight of the building at the time of outbreak of a fire from the fire. Especially, in the structure of disposing an ordinary adiabatic material around the bearing, if a fire breaks out after the adiabatic material is broken by the large shake of an earthquake, the bearing cannot be protected, and an aseismic structure trully possessing fireproof performance could not be manufactured. In the present method, to the contrary, since the high damping elastomer will not be broken if shaken heavily by an earthquake, it can fight fire after onset of an earthquake. Besides, by replacing the high damping elastomer after the fire, it is possible to re-use without giving any damage to the bearing itself.
This fireproof performance is further explained below. For example, as shown in FIG. 8, in the fire test in which the periphery of the shakeproof bearing 10 was covered with 60 mm thick high damping elastomer 21 at a clearance of 10 mm, and fireproof coverings 22 made of ceramic fibers were disposed at the upper and lower sides, and the assembly was put into a heating oven, there was no change in the performance after withstanding for 3 hours which is required in the fireproof performance of structures. Therefore, the thickenss of the high damping elastomer to be installed should be 40 mm or more, or preferably 60 mm or more. In the high damping elastomer 14 or its laminate 14a shown in FIG. 2 and FIG. 4, the thickness is 130 mm, and in actual fabrication the thickness of high damping elastomer is usually considerably larger than the specified values of 40 to 60 mm, and therefore the shakeproof bearing of this invention has a sufficient fireproof performance without giving any special consideration.
In order to further enhance the fireproof performance, a flame-retardant elastomer such as silicone rubber, fluororubber and chlorobutyl may be used as the high damping elastomer, or the high damping elastomer may be blended with flame retardants of addition type such as antimony oxide, organic ester phosphate, chlorinated paraffin and inorganic salt, or flame retardants of reaction type such as tetra-bromo-bis-phenol A.
Besides, by adding a coloring matter to the high damping elastomer, the bearing simultaneously possessing fashionableness may be also realized.
According to the invention, the bearing body and damper can be assembled in a single structure, and a shakeproof bearing having a larger damping capacity can be realized at a similar creep level as the conventional laminate rubber bearing made of natural rubber.
Besides, the high damping elastomer disposed around the bearing body as a damper exhibits the fireproof function at the same time, and the shakeproof bearing of this invention is also enhanced in the reliability in this aspect. | A shakeproof bearing or an earthquake-proofing structure (10) comprises a columnar bearing body (13) and a surrounding high damping elastomer (14). The bearing body (13) includes a stack of rigid plates (12) and elastic plates (11) alternating with one another. The high damping elastomer (14) may be shaped into an annular cylinder or, alternatively, may be in the form of a columnar stack of alternating annular rigid plates (18) and annular high-damping-elastomer plates (17). | 4 |
BACKGROUND
[0001] This application relates to high-power long-life actuators for positive displacement fluid movers such as liquid pumps, gas compressors and synthetic jets.
[0002] Positive displacement fluid movers can provide high flow and pressure however in order to be suitable for many applications such as medical devices; thermal management of computers, servers, LED lighting; and other electronics cooling applications these fluid movers must operate with low vibration and provide long life. Further, these applications require the fluid movers to be constructed in smaller and smaller sizes in order to fit in space constrained product platforms without loss of fluid performance.
[0003] If fluid movers could use two pistons that move in opposition to each other then vibration would be minimized but to make this two piston approach practical requires that the same force waveform be applied to each piston. Separate actuation of each piston adds size, mechanical complexity and cost and the challenge of matching the force on each piston would require a control scheme which adds further complexity and cost.
[0004] As such an unmet need exists for improvements in fluid mover actuation that enables integration of fluid mover components to achieve smaller sizes without loss of performance or life while providing a simple means to assure that an identical force waveform is applied to each piston.
SUMMARY
[0005] To satisfy these needs and overcome the limitations of previous efforts, the present application discloses a dual armature/diaphragm actuator with a stationary coil mounted between the armatures, where the resulting magnetic force is applied directly between the two pistons thereby assuring that both pistons experience the same instantaneous actuation force in order to minimize vibration. To further satisfy these needs and overcome the limitations of previous efforts, the means of actuation integrates the piston and actuator components to reduce the size of fluid movers for a given pumping power output, while eliminating any dynamic electrical components, such as vibrating wires that could lead to failure and reduced life.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings:
[0007] FIG. 1 illustrates an embodiment of a fluid mover actuator that provides for the same actuator force being applied to both armatures.
[0008] FIG. 2 is a sectional view of the actuator of FIG. 1 showing the flux path that occurs when the coil is energized.
[0009] FIG. 3 is a sectional view that illustrates how the actuation system of FIG. 1 is applied to a fluid mover.
[0010] FIG. 4 is sectional view of the fluid mover of FIG. 3 that shows the mounting of the stationary coil.
[0011] FIG. 5 is a sectional view illustrating how both sides of each diaphragm can be used to form additional fluid chambers for applying energy to fluids.
[0012] FIG. 6 provides sectional and exploded views of an armature design that increases actuator efficiency by improving coil utilization.
DETAILED DESCRIPTION
[0013] FIG. 1 illustrates certain key functional concepts of a fluid actuator according to an exemplary embodiment of the present invention where a stationary coil 6 is positioned between an identical pair of armatures 2 and 4 . When the coil is energized a magnetic field is generated within armatures 2 and 4 and the resulting flux loop path of the field is illustrated by the dotted lines in FIG. 2 . The magnetic field creates an attractive force in the air gap between the armatures that pulls the two armatures towards each other. Applying the force directly between the two armatures assures that the instantaneous forces, and therefore the force waveform, experienced by armatures 2 and 4 are always identical.
[0014] FIG. 3 illustrates how the actuator of FIG. 1 is used in a fluid moving device. Armatures 16 and 18 are bonded to respective diaphragms 8 and 10 . Diaphragms 8 and 10 each have an annular cantilever spring matrix making the diaphragms capable of larger axial displacements. In practice, diaphragms 8 and 10 would have an elastomeric over molding (not shown) to provide a pressure seal. Diaphragms 8 and 10 represent one of many kinds of diaphragms that could be used within the scope of the present invention while still exploiting the actuation principles thereof. The diaphragms may be configured, for example, as shown in International Patent Application No. PCT/US2011/022386, which is incorporated by reference herein in its entirety. Diaphragms 8 and 10 form a pressure tight seal with housing 12 . Compression chamber 20 is bounded by diaphragms 8 and 10 and housing 12 . When the coil is energized the magnetic forces cause armatures 16 and 18 to move towards each other along with their respective diaphragms 8 and 10 resulting in a volume reduction of fluid chamber 20 . When the coil is turned off, the potential energy stored in the diaphragm springs will push the armatures and diaphragms back in the opposite direction resulting in a volume increase of fluid chamber 20 . The resulting cyclic volume decrease and increase associated with switching the coil off and on will impart energy to the fluid in fluid chamber 20 providing the fluid energy needed for the particular application such as, for example, pumping liquids and gases or powering synthetic jets or other fluid moving applications such as mixing, metering or sampling to name a few.
[0015] The oscillation of armatures 16 and 18 result in reaction forces being transmitted to housing 12 via respective diaphragms 8 and 10 . To the degree that the masses of armatures 16 and 18 are equal and the spring stiffness of diaphragms 8 and 10 are equal, the reactions forces will cancel resulting in minimal housing vibration if the displacements of armatures 16 and 18 are equal. By delivering the same force amplitude and force waveform to each armature, a fluid moving actuator as disclosed herein may operate so that each armature will execute the same displacement amplitude and displacement waveform, thereby fulfilling the conditions required for zero or minimal housing vibration.
[0016] The fluid mover of FIG. 3 can be operated at its mechanical mass-spring resonance frequency where the resonance frequency is determined by the combined spring stiffness of the diaphragm and fluid and the mass of the fluid and armature.
[0017] The fluid mover of FIG. 3 is shown in FIG. 4 with a different sectional view in order to show how the coil may be rigidly mounted to housing 12 . In order to show the mounting arrangement, only one of the diaphragms is now shown in FIG. 4 . Coil 14 is held by coil clamps 22 and 24 which in turn are clamped into housing 12 . This stationary coil design eliminates the need for the moving power leads of a dynamic coil and also eliminates the potential failure of those leads or wires thereby promoting life and reliability.
[0018] With any of the above mentioned fluid moving applications, both sides of the diaphragms can be used for fluid work. For example, FIG. 5 shows the addition of end plates 26 and 28 which create respective fluid chambers 30 and 32 . Fluid chambers 30 and 32 can be used to convey energy to fluid for any of the above mentioned applications.
[0019] The scope of the present invention includes numerous additional variations to the fluid mover actuator described herein. For example the design of the armatures and the resulting flux path may be altered in many ways while still providing a force directly between the armatures by means of a stationary coil located between the armatures. FIG. 6 shows an armature design for improving electro-mechanical transduction efficiency. As shown in FIG. 6 , opposing armatures 40 and 42 are attached to respective diaphragms 34 and 36 with the diaphragms in turn being attached to housing 38 . A stationary coil 44 is rigidly mounted to housing 38 by coil arms 46 and 48 . In the design of FIG. 6 , the coil is more completely surrounded with the armature material compared to the design shown in FIGS. 3 and 4 , where a portion of the coil is outside the armature material. Sections of the coil that are outside the armature material generate less of a magnetic field in the armatures which reduces the actuator's efficiency. Further variations may include alternate components used to create the force such as permanent magnets and moving-magnet stationary-coil voice coil type actuators, where the armatures would be replaced with a voice-coil type magnet and backing magnet iron to provide a coil air gap having a permanent magnetic field. Specific subcomponent designs for an actuator according to the present invention will be determined by good design practice in response to specific design and end-product requirements.
[0020] The various embodiments of a fluid actuator according to the present invention can be driven at any frequency within the scope of the present invention. While performance advantages can be provided by operating the actuator at drive frequencies that are equal to or close to its mass-spring resonance, the scope of the present invention is not limited to the proximity of the drive frequency to the mass-spring resonance frequency. When drive frequencies are close enough to the mass-spring resonance that energy is stored in the resonance, then armature-diaphragm amplitudes will increase in proportion to the stored energy. The closer the drive frequency is to the instantaneous resonance frequency, the greater the stored energy and the greater the armature/diaphragm displacement and the greater the power transferred to the fluid in the fluid chamber for a given input power level. Operation of an actuator according to the present invention, either with or without stored energy, is considered within the scope of the present invention.
[0021] It is also understood that according to the various embodiments of a fluid mover actuator according to the present invention, the armatures would typically be made of ferrous type metals having high magnetic permeability but that the degree of permeability and loss characteristics required will be based on the requirements of a given application.
[0022] Many different drive circuits may be used to power a fluid mover actuator according to the present invention and will be apparent to one skilled in the art and these drive circuits may include resonance locking controls, such as a phase locked loop control or other CPU-based controls, to keep the drive frequency locked to the mechanical resonance frequency which can change due to changing system conditions. Many different voltage waveforms can also be used to drive the fluid mover actuator according to the present invention and waveform characteristics and duty cycles will be chosen according to the requirements of the end product or application.
[0023] Applications for a fluid mover actuator according to the present invention include moving air or liquids for heat exchange in thermal management applications via air pumps, liquid pumps or synthetic jets for a wide range of hot objects including electronics components such as microprocessors, power electronics components such as MODFETS, HBLEDs and any electronics components needing cooling as well as secondary heat exchange targets such as heatsinks, printed circuit cards and electronics enclosures. Products needing such cooling include servers, PC towers, laptops, HBLED lamps, consumer electronics, PDAs or sealed electronics enclosures such as in cell phones, telecommunications and military applications.
[0024] Other applications include general mixing of gases and particulate matter for chemical reactions, fluid metering; miniature air and fuel pumps for micro fuel cells; miniature pumps for liquid sampling, air sampling for bio-chem warfare agents and general chemical analysis or creating other material changes in suspended particulates such as comminution or agglomeration, or a combination of any of these processes, to name a few.
[0025] The foregoing description of some of the embodiments of the present invention have been presented for purposes of illustration and description. In the drawings provided, the subcomponents of individual embodiments provided herein are not necessarily drawn in proportion to each other, for the sake of functional clarity. In an actual product, the relative proportions of the individual components are determined by specific engineering design requirements. The embodiments provided herein are not intended to be exhaustive or to limit the invention to a precise form disclosed, and obviously many modifications and variations are possible in light of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and 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. Although the above description contains multiple specifications, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of alternative embodiments thereof. | A fluid mover includes a first dynamic armature attached to a flexible member and a second dynamic armature attached to a second flexible member. The fluid mover also includes a housing and first and second flexible members being attached to the housing so as to form a fluid chamber volume bounded by the housing and first and second flexible members. A stationary current carrying coil positioned between first and second armatures. The current carried by the coil generates a magnetic force acting on the armatures and wherein coil and armatures are positioned and configured so as to ensure that the instantaneous magnetic force experienced by the two armatures will always be identical regardless of the relative positions of the armatures and regardless of the time varying properties of the current. | 5 |
BACKGROUND
1. Field of Disclosure
This application relates generally to current sense transistors and, more specifically, to techniques to compensate for variations in the current sense ratio between a current sensing transistor and a main transistor.
2. Description of the Related Art
Current sense transistors have been used for many years in integrated circuit applications where accurate current sensing can provide information for both control and over-current protection. Sense transistors are typically constructed from a small part or section of a larger transistor that carries the main current of the device. For example, in a conventional metal oxide semiconductor field effect transistor (MOSFET) device, the sense transistor may comprise a small section of the channel region of the main power transistor. In operation, the sense transistor may sample a small fraction of the channel current of the power transistor, thereby providing an indication of the current in the main transistor. The sense transistor and main transistor device typically share a common drain and gate, but each has a separate source electrode.
Sense transistors are useful in many power delivery applications to provide current limit protection and accurate power delivery. In providing these functions, the sense transistor generally maintains a constant current sensing ratio (CSR) with respect to a main power transistor over a wide range of drain currents (100 mA to 10 amperes), temperatures (−25° C. to 125° C.), as well as fabrication process variations and mechanical stress/packaging variations. The ratio of drain current of the main power transistor to that of the sense transistor typically ranges between 20:1 to 800:1, or greater.
High electron mobility transistors (HEMTs) are attractive devices for achieving high performance in high power applications as they have high electron mobility and a wide band gap, and are capable of being processed with conventional equipment and methods not substantially different from those already developed for silicon and present generations of compound semiconductors. A particularly desirable material for building a HEMT is the wide-bandgap compound semiconductor known as gallium nitride (GaN). The GaN-based transistor is capable of maximizing electron mobility by forming a quantum well at the heterojunction interface between e.g., an aluminum gallium nitride (AlGaN) barrier layer and a GaN layer. GaN-based transistors have received much attention for high power applications since they have on-resistances that are typically one or more orders of magnitude less than those of silicon (Si)-based or gallium arsenide (GaAs)-based transistors and hence, are operable at higher temperatures with higher currents and can withstand high voltage applications.
BRIEF DESCRIPTION OF THE DRAWINGS
Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.
FIG. 1A is a schematic representation of cross-sectional view of a lateral-channel HEMT.
FIG. 1B is a schematic representation of top-view of a HEMT device including two HEMTs coupled together.
FIG. 2A is a circuit schematic of an example HEMT device that includes a main transistor and a sense transistor for sensing the drain current of the main transistor.
FIG. 2B is a circuit schematic that illustrates an equivalent representation of the HEMT device of FIG. 2A .
FIG. 2C is a circuit schematic of a HEMT device including a main transistor and two sense transistors.
FIG. 3 shows example waveforms that correspond to a sense voltage representative of the drain current of the main transistor of the HEMT devices of FIG. 2A-2C , a compensation signal, and a compensated sense voltage.
FIG. 4A is a circuit schematic illustrating one example implementation of a compensation circuit that outputs a compensated sense voltage.
FIG. 4B is a circuit schematic illustrating another example implementation of a compensation circuit that outputs a compensated sense voltage.
FIG. 4C is a circuit schematic illustrating yet another example implementation of a compensation circuit that outputs a compensated sense voltage.
FIG. 5 shows example normalized curves that correspond to a ratio of the drain current of the main transistor of the HEMT device in FIG. 2C to a sense current and a ratio of the drain current of the main transistor of the HEMT device in FIG. 2C to a compensated sense current.
FIG. 6 is a circuit schematic of another example HEMT device including a main transistor and two sense transistors.
DETAILED DESCRIPTION
Among the challenges that arise in the design of a sense transistor for use in a power integrated circuit (IC) with a GaN-based power transistor is the variation of the drain to source resistance of the power transistor with respect to its drain to source voltage. As a result, for a fixed drain current of the power transistor, the current sampled by the sense transistor varies as the drain to source voltage of the power transistor varies. This causes the current sense ratio to deviate from the desired constant value.
FIG. 1A is a schematic representation of cross-sectional view of an example lateral-channel HEMT 100 . HEMT 100 includes a substrate layer 110 , a first semiconductor layer 120 , and a second semiconductor layer 130 . First semiconductor layer 120 and second semiconductor layer 130 contact one another to form a heterojunction. Due to the material properties of semiconductor layers 120 and 130 , a two dimensional electron gas arises at the heterojunction. HEMT 100 also includes a source electrode 140 , a drain electrode 160 , and a gate electrode 150 . The selective biasing of gate electrode 150 regulates the conductivity between source electrode 140 and drain electrode 160 .
In the illustrated implementation, source electrode 140 and drain electrode 160 both rest directly on an upper surface of second semiconductor layer 130 to make electrical contact therewith. This is not necessarily the case. For example, in some implementations, source electrode 140 and/or drain electrode 160 penetrate into second semiconductor layer 130 . In some implementations, this penetration is deep enough that source electrode 140 and/or drain electrode 160 contact or even pass through the heterojunction. As another example, in some implementations, one or more interstitial glue, metal, or other conductive materials are disposed between source electrode 140 and/or drain electrode 160 and one or both of semiconductor layers 120 , 130 .
In the illustrated implementation, gate electrode 150 is electrically insulated from second semiconductor layer 130 by a single electrically-insulating layer 170 having a uniform thickness. This is not necessarily the case. For example, in other implementations, a multi-layer can be used to insulate gate electrode 150 from second semiconductor layer 130 . As another example, a single or multi-layer having a non-uniform thickness can be used to insulate gate electrode 150 from second semiconductor layer 130 .
The various features of lateral-channel HEMT 100 can be made from a variety of different materials, including Group III compound semiconductors. For example, first semiconductor layer 120 can be one of gallium nitride (GaN), indium nitride (InN), aluminum nitride (AlN), aluminum gallium nitride, (AlGaN), indium gallium nitride (InGaN), and indium gallium aluminum nitride (InGaAlN). In some implementations, first semiconductor layer 120 can also include compound semiconductors containing arsenic such as one or more of, e.g., gallium arsenide (GaAs), indium arsenide (InAs), aluminum arsenide (AlAs), indium gallium arsenide (InGaAs), aluminum gallium arsenide (AlGaAs), and indium aluminum gallium arsenide (InAlGaAs). Second semiconductor layer 130 can be, e.g., AlGaN, GaN, InN, InGaN, or AlInGaN. Second semiconductor layer 130 can also include compound semiconductors containing arsenic such as one or more of GaAs, InAs, AlAs, InGaAs, AlGaAs, or InAlGaAs. The compositions of first and second semiconductor layers 120 , 130 —which also can be referred to as active layers—are tailored such that a two-dimensional electron gas forms at the heterojunction. For example, in some implementations, the compositions of first and second semiconductor layers 120 , 130 can be tailored such that a sheet carrier density of between 10 11 to 10 14 cm −2 arises at the heterojunction. In some implementations, a sheet carrier density of between 5×10 12 to 5×10 13 cm −2 or between 8×10 12 to 1.2×10 13 cm −2 arises at the heterojunction. First and second semiconductor layers 120 , 130 can be formed above substrate layer 110 which can be, e.g., GaN, GaAs, silicon carbide (SiC), sapphire (Al 2 O 3 ), or silicon. First semiconductor layer 120 can be in direct contact with such a substrate layer, or one or more intervening layers can be present.
Source electrode 140 , drain electrode 160 , and gate electrode 150 can be made from various electrical conductors including, e.g., metals such as aluminum (Al), nickel (Ni), titanium (Ti), titanium tungsten (TiW), titanium nitride (TiN), titanium gold (TiAu), titanium aluminum molybdenum gold (TiAlMoAu), titanium aluminum nickel gold (TiAlNiAu), titanium aluminum platinum gold (TiAlPtAu), or the like. Insulating layer 170 can be made from various dielectrics suitable for forming a gate insulator including, e.g., (Al 2 O 3 ), zirconium dioxide (ZrO 2 ), aluminum nitride (AlN), hafnium oxide (HfO 2 ), silicon dioxide (SiO 2 ), silicon nitride (Si 3 N 4 ), aluminum silicon nitride (AlSiN), or other suitable gate dielectric materials. Insulating layer 170 can also be referred to as a passivation layer in that layer 170 hinders or prevents the formation and/or charging of surface states in the underlying second semiconductor layer 130 .
FIG. 1B is a schematic representation of a top-view of an example HEMT device including two HEMTs coupled together. As shown, source electrodes have metal pads that are coupled to a source metal bus 192 used to couple source electrodes of HEMTs 180 and 190 together. Similarly, gate electrodes have metals pads that are coupled to a gate metal bus 194 used to couple gate electrodes of HEMTs 180 and 190 together and drain electrodes have metal pads that are coupled to a drain metal bus 196 used to coupled drain electrodes of HEMTs 180 and 190 together. As such, in this configuration, the illustrated HEMT device includes two HEMTs coupled in parallel. In one example, one of HEMTs 180 and 190 can be used as a sense transistor to sense the drain current of the other, which may be referred to as a main transistor. In another example, the HEMT device can include more than one sense transistor coupled to the main transistor in parallel in the same manner as explained above. The main transistor and the one or more sense transistors may be formed on a single die. In some examples, there can be a resistor coupled between the metal pad of the source electrode of each one of the sense transistors and source metal bus 192 . This resistor can be used to measure the current in the sense transistor(s). In the depicted example, for illustrative purposes only, the gate electrodes of HEMTs 180 and 190 are drawn to be smaller in one dimension than the source and drain electrodes. In other examples, gate electrodes can be approximately the same size as the source and/or drain electrodes.
FIG. 2A is a circuit schematic that includes an example HEMT device having a main transistor and a sense transistor for sensing the drain current of the main transistor. As shown, a HEMT Q 1 202 , also referred to as main transistor 202 , is coupled across a current source 200 between a node A and a ground reference 210 . Ground reference 210 represents the lowest voltage or potential against which all voltages of the illustrated circuit are measured or referenced. HEMT Q 1 202 has a drain terminal coupled to the node A, a source terminal coupled to ground reference 210 , and a control terminal (gate) also coupled to ground reference 210 . In the example of FIG. 2A , transistor 202 is a depletion mode transistor, being in a conducting state when the gate terminal is less than a threshold voltage above the source terminal. A depletion mode transistor is sometimes called a normally-on transistor. Therefore, transistor 202 is in a conducting state when the source terminal and the gate terminal are coupled to the same potential. In a typical application, the gate terminal may be coupled to a driver circuit that changes the voltage at the gate terminal to switch the transistor between a conducting state and a non-conducting state. In one example, HEMT Q 1 202 is a Group III compound semiconductor FET such as, for example, a GaN FET. It should be noted that, with appropriate modification, other transistor types such as, for example, a metal oxide semiconductor FET (MOSFET) or a junction FET (JFET) can also be used as the main transistor.
The HEMT device includes a HEMT sense transistor Q SEN 204 for sensing the drain current of the main transistor. Sense transistor 204 shares drain and control terminals with those of main transistor 202 . Source terminal of sense transistor 204 is coupled to ground reference 210 with a sense resistor R SEN 206 . Sense transistor 204 is also a depletion mode transistor; hence, sense transistor 204 is in a conducting state when the voltage at its gate terminal is less than a threshold voltage above its source terminal.
Current source 200 is coupled to provide a current I D to the node A. The current I D is approximately equal to the drain current of main transistor 202 . A relatively small fraction (e.g., one hundredth or less) of this current is drawn by sense transistor 204 as a sense current I SEN 208 . Therefore, sense current I SEN 208 is representative of the drain current of main transistor 202 . Since sense resistor R SEN 206 conducts the same current as sense transistor 204 , the voltage that develops across sense resistor R SEN 206 , which is referred to as a sense voltage V SEN 212 , is representative of sense current I SEN 208 . Hence, V SEN 212 sense voltage is also representative of the drain current of main transistor 202 . In operation, sense voltage V SEN 212 is less than the threshold voltage of sense transistor 204 so that sense transistor 204 is in the conducting state when main transistor 202 is conducting current.
FIG. 2B is a schematic of an equivalent circuit of the circuit of FIG. 2A with HEMTs Q 1 202 and Q SEN 204 in the ON state. When conducting current, main transistor 202 presents a certain amount of resistance between its drain and source terminals (i.e., drain to source resistance). As such, main transistor 202 can be modeled as a resistor R FET 222 coupled between the node A and ground reference 210 . In this case, resistor R FET 222 is representative of the drain to source resistance of main transistor 202 . Similarly, sense transistor 204 can be modeled as a resistor 224 coupled between sense resistor R SEN 206 and the node A. Resistor 224 represents the drain to source resistance presented by sense transistor 204 when sense transistor 204 is in a saturated conductive state. Resistor 224 may have a resistance that is several times (e.g., 100 times) the resistance of resistor R FET 222 such that sense current I SEN 208 is a relatively small fraction of the current through resistor 222 .
It can be shown that sense voltage V SEN 212 is given by:
V SEN = I D R SEN ( 1 + K ) + R SEN R FET ( 1 )
where K represents the ratio of the resistance of resistor 224 to the resistance of resistor R FET 222 . As can be seen from equation (1), sense voltage V SEN 212 (and hence, sense current I SEN 208 ) is dependent on the drain to source resistance of main transistor 202 (resistance of resistor R FET 222 ). Therefore, the ratio of the drain current of main transistor 202 to sense current I SEN 208 is also dependent on the drain to source resistance of main transistor 202 . Assuming that sense current I SEN 208 is several orders of magnitude (e.g., at least 100 times) lower than the drain current of main transistor 202 (I SEN <<I D ), the drain to source resistance of main transistor 202 can be approximated as:
R FET = V DS I D ( 2 )
where V DS corresponds to the voltage between the drain and the source terminals (i.e., the drain to source voltage) of main transistor 202 . Substituting this expression for resistor R FET 222 in equation (1), an alternative expression for sense voltage V SEN 212 can be obtained as follows:
V SEN = 1 ( 1 + K ) I D R SEN + 1 V DS ( 3 )
This equation implies that sense current I SEN 208 , which can be obtained by dividing sense voltage V SEN 212 by the resistance of sense resistor R SEN 206 , deviates from I D /(1+K) due to the influence of the drain to source voltage of main transistor 202 . In other words, the drain to source voltage of main transistor 202 causes sense current I SEN 208 to deviate from a fixed fraction of the drain current of main transistor 202 . The amount that sense current I SEN 208 deviates from I D /(1+K) decreases with increasing drain to source voltage of main transistor 202 . To compensate for this deviation, both sense voltage V SEN 212 and the drain to source voltage of main transistor 202 may need to be measured.
FIG. 2C is a schematic of a circuit that includes an example HEMT device having a main transistor and two sense transistors. This circuit is similar to the circuit of FIG. 2A except that the HEMT device in FIG. 2C includes another HEMT as second sense transistor Q SEN2 214 for measuring the drain to source voltage of main transistor 202 . In one example, main transistor Q 1 202 , sense transistor Q SEN 204 , and second sense transistor Q SEN2 214 are Group III compound semiconductor HEMTs. Second sense transistor 214 shares drain and control terminals with those of main transistor 202 . As further shown, source terminal of second sense transistor 214 is coupled to ground reference 210 with a resistor R S 216 . If the resistance of resistor R S 216 (e.g., 10 4 ohms) is several orders of magnitude greater than the drain to source resistance of second sense transistor 214 (e.g., between 10 and 100 ohms) when second sense transistor 214 is in a saturated conductive state, then the voltage that develops across resistor R S 216 is approximately equal to the drain to source voltage of main transistor 202 . The drain to source voltage of main transistor 202 may also be referred to as a voltage V DS . Therefore, in this case, the voltage across resistor R S 216 can be used to measure the voltage V DS .
FIG. 3 shows example curves that represent a sense voltage representative of the drain current of the main transistor of the HEMT devices of FIG. 2A-2C , a compensation signal, and a compensated sense voltage. Curve 312 is one possible representation of sense voltage V SEN 212 as a function of the voltage V DS . Curve 312 starts at zero when the voltage V DS is zero volts and approaches V LIM (where V LIM corresponds to (I D R SEN )/(1+K)) as the voltage V DS increases. Curve 314 is one possible representation of a compensation signal U CMP as a voltage that is a function of the voltage V DS . Compensation signal U CMP can be used to reduce the influence of the voltage V DS on sense voltage V SEN 212 , and hence, reduce the influence of the drain to source resistance of main transistor 202 on sense current I SEN 208 . In one example, curve 314 is a linear ramp with a slope of −m (i.e., a linear ramp with a negative slope). Curve 316 is one possible representation of a compensated sense voltage V SENCMP that can be obtained by adding curve 314 to curve 312 .
After adding the compensation signal U CMP to sense voltage V SEN 212 given by equation (1) and manipulating the resulting expression such that the compensated sense voltage V SENCMP has the same value for a lower limit V DSL and a higher limit V DSH , the following expression for the compensated sense voltage V SENCMP can be obtained:
V SENCMP = V LIM V NOM V DSL V DSH ( ( V DSL V LIM + 1 ) ( V DSH V LIM + 1 ) 1 V LIM + 1 V DS - V DS ) ( 4 )
where the lower limit V DSL and the higher limit V DSH represent the lower and the higher limits, respectively, of a range of values of the voltage V DS over which the influence of the voltage V DS on sense voltage V SEN 212 is aimed to be reduced. In equation (4), a nominal voltage V NOM represents a value of the compensated sense voltage V SENCMP that results in a desired ratio (e.g., 1/(1+K)) between a compensated sense current (which can be found by dividing the compensated sense voltage V SENCMP by the resistance of sense resistor R SEN 206 ) and the drain current of main transistor 202 for the lower limit V DSL and the higher limit V DSH . In one example, nominal voltage V NOM is equal to V LIM which is I D R SEN /(1+K). As further illustrated by curve 316 , the compensated voltage V SENCMP reaches a maximum value V MAX when the voltage V DS equals V DSM between the lower limit V DSL and the higher limit V DSH . The maximum value V MAX can be expressed as follows:
V MAX = V NOM V LIM 2 ( V DSL V LIM + 1 ) ( V DSH V LIM + 1 ) V DSL V DSH ( 1 - 1 ( V DSL V LIM + 1 ) ( V DSH V LIM + 1 ) ) 2 ( 5 )
In the illustrated example, the compensated sense voltage V SENCMP may vary less with respect to the voltage V DS when the voltage V DS is between the lower limit V DSL and higher limit V DSH . This means that the resulting compensated sense current may deviate less from I D /(1+K) when the drain to source resistance of main transistor 202 is between a low value of R DSL (i.e., V DSL /I D ) and a high value of R DSH (i.e., V DSH /I D ). In this manner, the influence of the drain to source resistance of main transistor 202 on sense current I SEN 208 can be reduced such that the ratio of the drain current of main transistor 202 to sense current I SEN 208 deviates less from the desired value of (1+K).
FIG. 4A is a circuit schematic illustrating one example implementation of a compensation circuit that outputs the compensated sense voltage. Compensation circuit 400 includes amplifying stages 410 , 420 and a differential amplifier 430 . Amplifying stage 410 is coupled to receive the voltage across resistor R S 216 as the voltage V DS and outputs an amplified version of the voltage V DS to a negative input terminal of differential amplifier 430 . Amplifier 420 is coupled to receive the voltage across sense resistor R SEN 206 as sense voltage V SEN 212 and outputs an amplified version of sense voltage V SEN 212 to a positive input terminal of differential amplifier 430 . Amplifying stages 410 and 420 have respective gains of A 1 and A 2 . Differential amplifier 430 has a gain of A 3 and is coupled to output an amplified version of the difference between the signal at its positive input terminal and the signal at its negative input terminal. In other words, differential amplifier 430 outputs a signal that is equal to A 3 times (A 2 V SEN −A 1 V DS ).
It can be shown that if the values of A 1 , A 2 , and A 3 are chosen as follows:
A 1 = 1 A 2 = ( ( 1 + K ) R DSL R SEN + 1 ) ( ( 1 + K ) R DSH R SEN + 1 ) A 3 = R SEN 2 ( 1 + K ) 2 R DSL R DSH ,
then the signal at the output of differential amplifier 430 corresponds to compensated sense voltage V SENCMP given by equation (4). As previously explained, this signal will be equal to I D R SEN /(1+K) when the drain to source resistance of main transistor 202 is equal to the low value of R DSL or the high value of R DSH . Accordingly, if this signal is applied to sense resistor R SEN 406 such as, for example, by coupling sense resistor R SEN 406 between the output of differential amplifier 430 and ground reference 210 , the resulting current in sense resistor R SEN 406 (which has the same value as resistor R SEN 206 ) becomes representative of the compensated sense current and equal to I D /(1+K) when the drain to source resistance of main transistor 202 is equal to the low value of R DSL or the high value of R DSH . In addition, when the drain to source resistance of main transistor 202 varies between the low value of R DSL and the high value of R DSH , the deviation of the compensated sense current from I D /(1+K) is less than the deviation of sense current I SEN 208 from I D /(1+K). Consequently, when the drain to source resistance of main transistor 202 varies between the low value of R DSL and the high value of R DSH , the ratio of the drain current of main transistor 202 to the compensated sense current varies less than the ratio of the drain current of main transistor 202 to sense current I SEN 208 . In this manner, change in the ratio of the drain current of main transistor 202 to sense current I SEN 208 due to the variation in the drain to source resistance of main transistor 202 can be compensated for over a range of values of the drain to source resistance of main transistor 202 .
FIG. 4B is a circuit schematic illustrating another example implementation of the compensation circuit that outputs the compensated sense voltage. Compensation circuit 400 in FIG. 4B is equivalent to compensation circuit 400 in FIG. 4A but implemented with different gain values A 4 , A 5 , and A 6 for amplifying stages 410 , 420 and differential amplifier 430 . With the following choices for values of A 4 , A 5 and A 6 :
A 4 = R SEN 2 ( 1 + K ) 2 R DSL R DSH A 5 = ( R DSL + R SEN ( 1 + K ) ) ( R DSH + R SEN ( 1 + K ) ) R DSL R DSH A 6 = 1
the resulting compensated sense voltage V SENCMP 416 and compensated sense current are the same as those that are described for FIG. 4A .
FIG. 4C is a circuit schematic illustrating yet another example implementation of the compensation circuit that outputs the compensated sense voltage. Compensation circuit 400 in FIG. 4C includes a differential amplifier 440 having a gain of A and resistors R 1 442 , R 2 444 , R 3 446 , and R 4 448 . Differential amplifier 440 has a negative input terminal coupled to resistor R 1 442 and a positive input terminal coupled to resistor R 3 446 . Resistor R 1 442 and resistor R 3 446 are on the other end coupled to receive the voltage across resistor R S 216 and sense voltage V SEN 212 , respectively. Resistor R 2 444 is coupled between the negative input terminal and the output of differential amplifier 440 and resistor R 4 448 is coupled between the positive input terminal of differential amplifier 440 and ground reference 210 . The output of differential amplifier 440 is coupled to sense resistor 406 , which has the same value as resistor R SEN 206 . In the illustrated example, resistors R 1 442 , R 2 444 , R 3 446 , and R 4 448 and gain value A can be chosen such that the resulting compensated sense voltage V SENCMP 416 and compensated sense current are the same as those that are described for one of FIG. 4A and FIG. 4B . In the example circuit of FIG. 4C , differential amplifier 440 may be an operational amplifier with a gain value A high enough to be negligible in the computation of values for the values of resistors as is known in the art. In other words, with resistors R 1 442 , R 2 444 , R 3 446 , and R 4 448 and gain value A chosen appropriately, compensation circuit 400 in FIG. 4C can be made equivalent to compensation circuit 400 in one of FIG. 4A and FIG. 4B .
FIG. 5 shows example curves that correspond to a ratio of the drain current of the main transistor of the HEMT device in FIG. 2C to a sense current and a ratio of the drain current of the main transistor of the HEMT device in FIG. 2C to a compensated sense current. The values are normalized to a desired nominal value to show the relative deviations from the desired nominal value. Curve 510 is one possible representation of the ratio of the drain current of main transistor 202 to sense current I SEN 208 as a function of the drain to source resistance of main transistor 202 . Curve 520 is one possible representation of the ratio of the drain current of main transistor 202 to the compensated sense current as a function of the drain to source resistance of main transistor 202 . The compensated sense current may be obtained by using compensation circuit 400 in one of FIG. 4A , FIG. 4B , and FIG. 4C . In the illustrated example, the low value R DSL and the high value R DSH of the drain to source resistance of main transistor 202 are chosen as 0.12 ohms and 0.22 ohms, respectively. In addition, the value of K, which represents the ratio of the resistance of resistor 224 to the resistance of resistor R FET 222 , is adjusted differently for curves 510 and 520 such that curve 510 and curve 520 have the same value for the high value R DSH of the drain to source resistance of main transistor 202 . In this case, this value of curves 510 and 520 may represent the desired ratio of the drain current of main transistor 202 to sense current I SEN 208 . Also, curves 510 and 520 are normalized with respect to this value such that the numbers on the y-axis represent the corresponding ratios in terms of percentage of this value.
As further shown, under these conditions, curve 510 increases as the drain to source resistance of main transistor 202 decreases from the high value R DSH of 0.22 ohms and becomes approximately equal to 110% (e.g., 111%) of the desired ratio when the drain to source resistance of main transistor 202 is equal to the low value R DSL of 0.12 ohms. In other words, curve 510 deviates up to 11% from the desired ratio as the drain to source resistance of main transistor 202 varies between the low value R DSL of 0.12 ohms and the high value R DSH of 0.22 ohms. On the other hand, curve 520 has the same desired ratio when the drain to source resistance of main transistor 202 is equal to the low value R DSL of 0.12 ohms and deviates less than 2% from the desired ratio as the drain to source resistance of main transistor 202 varies between the low value R DSL of 0.12 ohms and the high value R DSH of 0.22 ohms. Therefore, compensation circuit 400 in one of FIG. 4A , FIG. 4B and FIG. 4C can be used to generate the compensated sense current such that the variation in the ratio of the drain current of main transistor 202 to sense current I SEN 208 is reduced with respect to the variation in the drain to source resistance of main transistor 202 .
FIG. 6 is a schematic of another circuit that includes an example HEMT device having a main transistor and two sense transistors. The HEMT device in FIG. 6 is similar to the HEMT device in FIG. 2C except that each one of main transistor 202 and sense transistors 204 and 214 are coupled to a corresponding MOSFET to form a cascode configuration. Specifically, the source terminal of main transistor 202 is coupled to the drain terminal of MOSFET Q 2 642 , the source terminal of sense transistor 204 is coupled to the drain terminal of MOSFET Q 3 644 , and the source terminal of second sense transistor 214 is coupled to the drain terminal of MOSFET Q 4 646 . In one example, main transistor 202 in FIG. 6 may be a normally-on HEMT (e.g., a GaN based normally-on HEMT). Typically, a normally-on HEMT can be coupled to a normally-off (enhancement mode) MOSFET in a cascode configuration to ensure reliable and easy switching. In the illustrated example, normally-off MOSFETs Q 2 642 , Q 3 644 , and Q 4 646 are coupled to receive a drive signal U DR 640 at their respective control (gate) terminals. As such, drive signal U DR 640 controls the switching of MOSFETs Q 2 642 , Q 3 644 , and Q 4 646 .
Similar to main transistor 202 in FIG. 2C , main transistor 202 in FIG. 6 can use compensation circuit 400 in one of FIG. 4A , FIG. 4B , and FIG. 4C to generate a compensated current sense signal to reduce the variation in the ratio of the drain current of main transistor 202 to sense current I SEN 208 with respect to the variation in the drain to source resistance of main transistor 202 over a range of values of the drain to source resistance of main transistor 202 . It should be noted that in the case of main transistor 202 in FIG. 6 , the drain to source resistances of main transistor 202 , sense transistor 204 , and second sense transistor 214 also include the drain to source resistances of the corresponding MOSFETs. | A method for sensing the current in a high-electron-mobility transistor (HEMT) that compensates for changes in a drain-to-source resistance of the HEMT. The method includes receiving a sense voltage representative of the current in the HEMT, receiving a compensation signal representative of a drain-to-source voltage of the HEMT, and outputting as a compensated sense voltage a linear combination of the sense voltage and the compensation signal. | 6 |
TECHNICAL FIELD
[0001] The present invention relates to an in-vehicle charging apparatus configured to charge a storage battery serving as the power source of a vehicle such as an electric vehicle, using a power supply of a house, for example.
BACKGROUND ART
[0002] In recent years, charging of storage batteries installed in a vehicle such as an electric vehicle using a power supply of a house (house of the owner of the vehicle) has been in practice. Since the power supply of a house supplies power to various electric devices such as an air conditioner, an overcurrent flowing through a power supply circuit may be caused by, for example, an increase in the number of electric devices in use. When an overcurrent occurs, the power supply circuit is shut off to stop supply of the power to the electric devices, thus making all the electric devices temporarily unusable.
[0003] Conventionally, electric device systems configured to reduce a current amount according to a decrease in a receiving voltage have been known as a method of preventing an overcurrent flowing through a power supply circuit in a house (for example, Patent Literature (hereinafter, abbreviated as PTL) 1). In an electric device system of PTL 1, when a decrease in a receiving voltage is detected by a voltage detector, a current amount in the entire system is reduced by controlling a power converter according to this decrease.
CITATION LIST
Patent Literature
PTL 1
[0000]
Japanese Patent Application Laid-Open No. 2003-92829
SUMMARY OF INVENTION
Technical Problem
[0005] The system according to PTL 1, however, reduces a current amount of the system without taking into consideration a current amount for other electric devices in use. As a result, the occurrence of overcurrent due to a current used in the entire system involves a problem in that all the electric devices become temporarily unusable because the power supply circuit is shut off.
[0006] It is an object of the present invention to provide an in-vehicle charging apparatus capable of preventing an in-vehicle charger from becoming unable to perform charge and also preventing an unusable state of another electric device in a house or the like by decreasing the input current of the in-vehicle charger when the use of the other electric device is started during the charge in the house or the like.
Solution to Problem
[0007] An in-vehicle charging apparatus according to an aspect of the present invention is an apparatus installed in a vehicle and configured to charge a storage battery installed in the vehicle, using a power source that is connected to an electric device and that is provided outside the vehicle, the apparatus including: a charger that receives a variable input current value flowing from the power source for charging the storage battery; a measurement section that measures the input current value of the charger and an input voltage value on the side of the power source of the charger; and a control section that controls the input current value of the charger, in which: the control section varies the input current value of the charger into a plurality of values, and calculates a correspondence between the input current values measured by the measurement section during the varying, and input voltage values corresponding to the respective input current values; and the control section controls, when an input voltage value varies while the input current value measured by the measurement section remains the same during charge of the storage battery, the input current value of the charger so that the input current value of the charger corresponds to the input voltage value before the varying, based on the correspondence.
Advantageous Effects of Invention
[0008] According to the present invention, it is possible to prevent an in-vehicle charger from becoming unable to perform charge and also to prevent an unusable state of another electric device in a house or the like by decreasing the input current of the in-vehicle charger when the use of the other electric device is started during the charge in the house or the like.
BRIEF DESCRIPTION OF DRAWINGS
[0009] FIG. 1 illustrates a configuration of a charging system according to an embodiment of the present invention;
[0010] FIG. 2 illustrates the relationship between time and an input current in a method of finding the relationship between an input voltage and an input current as a first-order approximation straight line according to the embodiment of the present invention;
[0011] FIG. 3 is a flowchart illustrating how to find a first-order approximation straight line according to the embodiment of the present invention;
[0012] FIG. 4 illustrates the relationship between an input voltage and an input current on the found first-order approximation straight line according to the embodiment of the present invention;
[0013] FIG. 5 is a flowchart illustrating a control method of the input current of a charger after the start of charge according to the embodiment of the present invention;
[0014] FIG. 6 illustrates a control for decreasing the input current of the charger after the start of charge according to the embodiment of the present invention; and
[0015] FIG. 7 illustrates a control for increasing the input current of the charger after the start of charge according to the embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Embodiments
<Configuration of Charging System>
[0017] FIG. 1 illustrates a configuration of charging system 100 according to an embodiment of the present invention.
[0018] House 150 is a house of the owner of vehicle 160 , for example. House 150 includes socket 105 connected to in-vehicle charging apparatus 170 of vehicle 160 . House 150 has power supply circuit 180 that supplies a power supply current from power source 101 . House 150 includes breaker board 106 that shuts off power supply circuit 180 when an overcurrent flows through power supply circuit 180 .
[0019] Vehicle 160 charges storage battery 115 installed in vehicle 160 , by in-vehicle charging apparatus 170 connected to socket 105 , using power source 101 supplied to the inside of house 150 from, for example, a power plant. Vehicle 160 is an electric vehicle which runs using storage battery 115 as a driving source.
[0020] In-vehicle charging apparatus 170 charges storage battery 115 installed in vehicle 160 . A configuration of in-vehicle charging apparatus 170 will be described below in detail.
[0021] Power supply circuit 180 includes power source 101 , output impedance 102 of power source 101 , and impedance 104 of the wiring which connects power source 101 and charger 114 . Power supply circuit 180 is a circuit for supplying a power source from power source 101 to electric device 103 or in-vehicle charging apparatus 170 .
[0022] <Configuration of in-Vehicle Charging Apparatus>
[0023] In-vehicle charging apparatus 170 has voltage measurement section 111 , current measurement section 112 , control section 113 , and charger 114 .
[0024] Voltage measurement section 111 measures the input voltage of charger 114 and outputs the measured voltage value to control section 113 .
[0025] Current measurement section 112 measures the input current of charger 114 corresponding to the input voltage of charger 114 and outputs the measured current value to control section 113 .
[0026] Control section 113 finds for the relationship between the plurality of measured voltage values inputted from voltage measurement section 111 and the plurality of measured current values corresponding to the plurality of respective measured voltage values inputted from current measurement section 112 as a first-order approximation straight line, and stores the found values as a table. Control section 113 controls the input current of charger 114 according to the table of the found first-order approximation straight line. A method of finding a first-order approximation straight line and a control method of the input current during the charge will be described below.
[0027] Charger 114 charges storage battery 115 with an input current controlled by control section 113 , using power source 101 .
[0028] <Method of Finding First-Order Approximation Straight Line>
[0029] FIG. 2 illustrates the relationship between time and an input current in a method of finding the relationship between an input voltage and an input current as a first-order approximation straight line. FIG. 3 is a flowchart illustrating how to find a first-order approximation straight line in the present embodiment. FIG. 4 illustrates the relationship between an input voltage and an input current on the found first-order approximation straight line.
[0030] Control section 113 finds a first-order approximation straight line, for example, before the start of charge.
[0031] Control section 113 varies input current Ic in sequence at predetermined time intervals and acquires the measured value of input voltage Vc at every timing of varying input current Ic. For example, as illustrated in FIG. 2 , control section 113 varies input current Ic in sequence in order of “0,” “1/4 Icmax,” “2/4 Icmax,” “3/4 Icmax,” and “Icmax,” and acquires the measured value of each input voltage Vc. Input current Ic and input voltage Vc which have been acquired are associated and stored in a table.
[0032] Specifically, as illustrated in FIG. 3 , voltage measurement section 111 first measures input voltage Vc corresponding to input current Ic=0 (Step ST 301 ).
[0033] Next, voltage measurement section 111 measures input voltage Vc corresponding to input current Ic=1/4 Icmax (Step ST 302 ).
[0034] Next, voltage measurement section 111 measures input voltage Vc corresponding to input current Ic=2/4 Icmax (Step ST 303 ).
[0035] Next, voltage measurement section 111 measures input voltage Vc corresponding to input current Ic=3/4 Icmax (Step ST 304 ).
[0036] Next, voltage measurement section 111 measures input voltage Vc corresponding to input current Ic=Icmax (Step ST 305 ).
[0037] Next, control section 113 acquires input current Ic and input voltage Vc in each of Steps ST 301 to ST 304 , and finds the relationship between input current Ic and input voltage Vc which are acquired as a first-order approximation straight line using the least-squares method (Step ST 306 ).
[0038] Next, control section 113 determines whether the error of the least-squares method used for finding the first-order approximation straight line is equal to or less than a constant value (Step ST 307 ).
[0039] When the error of the least-squares method is equal to or less than the threshold (Step ST 307 : YES), and control section 113 determines the first-order approximation straight line found in Step ST 306 (Step ST 308 ), and complete the process.
[0040] On the other hand, when the error of the least-squares method is larger than a threshold value, (Step ST 307 : NO) control section 113 repeats the process of Steps ST 301 to ST 306 .
[0041] With the above-described method, control section 113 finds the relationship between the value of each varied input current Ic and the measured value of each input voltage Vc corresponding to each input current Ic, as first-order approximation straight line # 301 illustrated in FIG. 4 . The method of finding first-order approximation straight line # 301 is not limited to the least-squares method, and any other appropriate methods can be used.
[0042] The slope of first-order approximation straight line # 301 is equal to synthetic impedance Zs (Zs=ZP+ZL) obtained by synthesizing output impedance ZP of power source 101 and impedance ZL of the wiring between power source 101 and charger 114 .
[0043] <Control Method of Input Current of Charger During Charge>
[0044] When the amount of power used for electric device 103 in house 150 increases during the charge of in-vehicle charging apparatus 170 , the input voltage to charger 114 declines as a result. In this case, the control is performed as follows.
[0045] FIG. 5 is a flowchart illustrating a control method of the input current of charger 114 after the start of charge. FIG. 6 illustrates a control for decreasing the input current of charger 114 after the start of charge. FIG. 7 illustrates a control for increasing the input current of charger 114 after the start of charge.
[0046] In FIG. 6 , Vc 1 is the input voltage before the decrease, Vc 2 is the input voltage after the decrease, Ic 1 is the input current before the decrease, and Ic 2 is the input current after the decrease. ΔVcr is a voltage reduction caused by an increase in load current Id flowing through electric device 103 . ΔIcr is a current decreased by the control of control section 113 . Vkr is the value of input voltage Vc at the intersection of first-order approximation straight line # 301 and the vertical axis.
[0047] In FIG. 7 , Vc 3 is the input voltage before the increase, Vc 4 is the input voltage after the increase, Ic 3 is the input current before the increase, and Ic 4 is the input current after the increase. ΔVcs is a voltage rise caused by a decrease in load current Id flowing through electric device 103 . ΔIcs is a current increased by the control of control section 113 . Vks is the value of input voltage Vc at the intersection of first-order approximation straight line # 301 and the vertical axis.
[0048] Control section 113 controls the input current of charger 114 using first-order approximation straight line # 301 beforehand found after the start of charge.
[0049] First, control section 113 acquires the measured value of input voltage Vc from voltage measurement section 111 and also acquires the measured value of input current Ic from current measurement section 112 (Step ST 501 ).
[0050] Next, control section 113 determines whether the charge is necessary (Step ST 502 ). For example, control section 113 determines that the charge is unnecessary when storage battery 115 is fully charged, and determines that the charge is necessary when storage battery 115 is not fully charged.
[0051] When determining that the charge is unnecessary (Step ST 502 : NO), control section 113 completes the process.
[0052] On the other hand, when determining that the charge is necessary (Step ST 502 : YES), control section 113 determines whether the acquired measured value of the input voltage and the acquired measured value of the input current are positioned on first-order approximation straight line # 301 (Step ST 503 ).
[0053] When the input voltage is stable and the values are positioned on first-order approximation straight line # 301 (Step ST 503 : YES), an overcurrent does not flow through power supply circuit 180 even if the input current of charger 114 is not adjusted. Control section 113 therefore returns to the process of Step ST 502 .
[0054] On the other hand, when the values are not positioned on first-order approximation straight line # 301 (Step ST 503 : NO), control section 113 determines whether input voltage Vc decreases (Step ST 504 ).
[0055] When input voltage Vc decreases (Step ST 504 : YES), control section 113 controls charger 114 so as to decrease input current Ic according to first-order approximation straight line # 301 (Step ST 505 ).
[0056] Specifically, as illustrated in FIG. 6 , assuming that input current Ic is constant when input voltage Vc decreases from Vc 1 to Vc 2 , control straight line # 601 is found which has the same slope as that of first-order approximation straight line # 301 and passes through input voltage Vc 2 after the decrease. Control section 113 controls charger 114 so as to decrease input current from Ic 1 so that the input voltage on found control straight line # 601 is substantially equal to input voltage Vc 1 before the decrease. Here, input voltage Vc substantially equal to input voltage Vc 1 is equal to or more than input voltage Vc 1 and equal to or less than a value larger than input voltage Vc by predetermined value α (where α>0) (Vc 1 ≦Vc≦(Vc 1 +α)). This is a concept including a control for decreasing input current from Ic 1 to an input current corresponding to a voltage higher than input voltage Vc 1 before the decrease by predetermined value α.
[0057] On the other hand, when input voltage Vc does not decrease (Step ST 504 : NO), control section 113 controls charger 114 so as to increase input current Ic (Step ST 506 ).
[0058] Specifically, as illustrated in FIG. 7 , assuming that input current Ic is constant when input voltage Vc increases from Vc 3 to Vc 4 , control straight line # 701 is found which has the same slope as that of first-order approximation straight line # 301 and passes through input voltage Vc 4 after the increase. Control section 113 controls charger 114 so as to increase the input current from Ic 4 so that the input voltage on found control straight line # 701 is substantially equal to input voltage Vc 3 before the increase. However, at this time, control section 113 controls the input current so as not to be equal to or more than maximum allowable current value Icmax. Here, input voltage Vc substantially equal to input voltage Vc 3 is equal to or less than input voltage Vc 3 and equal to or more than a value smaller than input voltage Vc by predetermined value β (where β>0) (Vc 3 ≧Vc≧(Vc 3 −β)). This is a concept including a control for increasing the input current from Ic 4 to an input current corresponding to a voltage lower than input voltage Vc 3 before the increase by predetermined value β.
[0059] Alternatively, in FIG. 5 , the process in Step ST 502 , which is to determine whether the charge is necessary may be performed, and after it is determined that the charge is necessary, the process in Step ST 501 , which is to acquire the measured value of input voltage Vc from voltage measurement section 111 and the measured value of input current Ic from current measurement section 112 , may be performed.
[0060] <Specific Example of Controlling to Decrease Input Current Ic 1 to Input Current Ic 2 >
[0061] With reference to FIG. 5 , an example case will be described in which in-vehicle charging apparatus 170 starts the charge for storage battery 115 using power source 101 when electric device 103 is stopped, and then electric device 103 starts to operate by receiving power supplied from power source 101 .
[0062] Voltage reduction ΔVc caused by the start of operation of electric device 103 can be found by Equation 1.
[0000] [1]
[0000] Δ Vc−ZP*ΔId (Equation 1)
[0063] where Id is a current flowing through electric device 103 , and
[0064] ZP is the output impedance of power source 101 .
[0065] Control section 113 decreases input current Ic to compensate the influence of voltage reduction ΔVc found from Equation 1.
[0066] Here, input voltage Ve can be found by Equation 2.
[0000] [2]
[0000] Vc=Vp−ZP ( Ic+Id )− ZL*Ic (Equation 2)
[0067] where Vp is the voltage of power source 101 ,
[0068] Ic is a current flowing from point A (refer to FIG. 1 ) of breaker board 106 to charger 114 ,
[0069] Id is a current flowing through electric device 103 ,
[0070] ZP is the output impedance of power source 101 , and
[0071] ZL is the impedance of wiring between power source 101 and charger 114 .
[0072] Equation 2 is modified to give input voltage Vc by Equation 3.
[0000] [3]
[0000] Vc =( Vp−ZP*Id )− ZS*Ic (Equation 3)
[0073] where Zs is the synthetic impedance of ZP and ZL.
[0074] Output voltage Vk of breaker board 106 for input current Ic=0 can be found by Equation 4.
[0000] [4]
[0000] Vk=Vp−ZP*Id (Equation 4)
[0075] where Vp is the voltage of power source 101 ,
[0076] Id is a current flowing through electric device 103 , and
[0077] ZP is the output impedance of power source 101 .
[0078] Equation 4 is substituted for Equation 3 to obtain Equation 5.
[0000] [5]
[0000] Vc=Vk−Zs*Ic (Equation 5)
[0079] From Equation 5, input voltage Vc 1 before the decrease and input voltage Vc 2 after the decrease are obtained by Equations 6 and 7, respectively.
[0000] [6]
[0000] Vc 1 =Vk−ZS*Ic 1 (Equation 6)
[0000] [7]
[0000] Vc 2 =Vk−ZS*Ic 2 (Equation 7)
[0080] Since voltage reduction ΔVc=Vc 2 −Vc 1 , Equation 6 is subtracted from Equation 7 to thereby obtain voltage reduction ΔVc by Equation 8.
[0000] Δ Vc=−ZS*ΔIc (Equation 8)
[0081] Equation 8 can be modified to obtain Equation 9.
[0000] [9]
[0000] Δ Ic=−ΔVc/ZS (Equation 9)
[0082] Therefore, decrease amount ΔIc of input current Ic compensating the influence of voltage reduction ΔVc can be found by Equation 9.
[0083] Here, Equation 1 is substituted for Equation 9 to obtain Equation 10.
[0000] [10]
[0000] Δ Id =−( ZS/ZP )*Δ Ic (Equation 10)
[0084] From Equation 10, since (ZS/ZP)≧1, ΔIc≦ΔId. Therefore, a decrease amount of ΔIc can be increased according to an increase in ΔId, and an increase amount of ΔIc can be increased according to a decrease in ΔId.
Advantageous Effects of Present Embodiment
[0085] As described above, in the present embodiment, the relationship between the input voltage and the input current of the charger is found as a first-order approximation straight line before the start of charge, and thereby, the input current of the charger is controlled according to the first-order approximation straight line after the start of charge. Thereby, according to the present embodiment, it is possible to prevent an in-vehicle charger from becoming unable to perform charge and also to prevent an unusable state of another electric device by decreasing the input current of the in-vehicle charger after the use of the other electric device is started during the charge.
[0086] According to the present embodiment, an input current is reduced according to a decrease in an input voltage caused by the start of the use of another electric device during the charge, and an input current is increased according to an increase in an input voltage caused by the stop of the use of the other electric device during the charge. As a result, charging with a maximum input current usable for charge can be used for the charge.
[0087] According to the present embodiment, a first-order approximation straight line is found again when a large error is caused from the least-squares method used for finding a first-order approximation straight line. Thereby, according to the present embodiment, it is possible to avoid finding an inaccurate first-order approximation straight line due to a variation in an input voltage caused by the start or stop of operation of another electric device while a first-order approximation straight line is found.
Variations of Present Embodiment
[0088] In the above-described embodiment, a control that decreases or increases the input current of charger 114 by a single level is performed. However, the present invention is not limited to this configuration, and a control that decreases or increases the input current of charger 114 by a plurality of levels may be performed.
[0089] In the above-described embodiment, a first-order approximation straight line is found before the start of charge, and the input current of the charger is controlled according to the first-order approximation straight line after the start of the charge. However, the present invention is not limited to this configuration, and a first-order approximation straight line may be found at predetermined timing after the start of charge.
[0090] The disclosure of Japanese Patent Application No. 2011-75791, filed on Mar. 30, 2011, including the specification, drawings and abstract, is incorporated herein by reference in its entirety.
INDUSTRIAL APPLICABILITY
[0091] An in-vehicle charging apparatus according to the present invention is suitable for charging a storage battery serving as the power source of a vehicle such as an electric vehicle, using the power supply of a house, for example.
REFERENCE SIGNS LIST
[0000]
100 Charging system
101 Power source
102 Output impedance
103 Electric device
104 Impedance
105 Socket
106 Breaker board
111 Voltage measurement section
112 Current measurement section
113 Control section
114 Charger
115 Storage battery
150 House
160 Vehicle
170 In-vehicle charging apparatus
180 Power supply circuit | Provided is a vehicle charging device ( 170 ) that uses a power source ( 101 ) outside of a vehicle ( 160 ) to charge a battery ( 115 ) installed in the vehicle ( 160 ). A charger ( 114 ) charges the battery ( 115 ). A voltage measurement unit ( 111 ) measures the input voltage corresponding to the input current in the charger ( 114 ). A current measurement unit ( 112 ) measures the input current (Ic) in the charger ( 114 ). A control unit ( 113 ) changes the input currents (Ic) of the charger ( 114 ) into a plurality of values, and controls the input current (Ic) when the input voltage (Vc) has changed, according to the corresponding relationship between the input currents (Ic), when each has been changed, and the measured input voltages (Vc). | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a card-operated lock, and in particular to a lock using a card with embossed letters matching with corresponding letters on letter profiles for lowering side levers and consequently for disengaging the letter profiles from their retaining plates to open the lock. This invention is designed to prevent opening of a lock without the designated card.
Today women who used to take care of homes are employed outside the home, and hence often nobody is at home during office hours. This then has become a good time for thefts. Such a burglary or theft not only causes loss of property but psychological injury to the victims can occur also. Such theft is mainly caused by the lack of reliable locks, and the fact that conventional locks can usually be opened by common tools. Therefore, home security is a primary concern. The lack of basic theft-proof facilities has become a public problem.
In view of the above problem, the Inventor has created a card-operated lock to provide a reliable lock which can not be opened by any tool other than the designated card.
SUMMARY OF THE INVENTION
The main objective of the present invention is to provide a card-operated lock using a card with embossed letters which match corresponding letters on letter profiles in the lock for lowering levers therein and consequently disengaging the letter profiles from their retaining plates to open the lock. The lock of this invention can not be opened without the designated card.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a card-operated lock according to the present invention.
FIG. 2 is a perspective view of the card-operated lock and card assembled according to the present invention.
FIGS. 3 (A)-(E) are sequential side sectional views illustrating operation of the card-operated lock according to the present invention as the card is inserted.
FIGS. 4 (A) and (B) are top sectional views illustrating operation of the card-operated lock according to the present invention wherein insertion of the card frees the lock shackle.
FIGS. 5 (A) and (B) are perspective views of another embodiment of card-operated lock according to the present invention.
FIGS. 6 (A) and (B) illustrate sequential operation of the card-operated lock embodiment of FIGS. 5 (A) and (B) according to the present invention.
FIGS. 7 (A)-(C) illustrate further sequential operation of the embodiment of card-operated lock of FIGS. 5 (A) and (B) according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The card-operate lock (10) according to the present invention includes a sliding block (21) with a sliding plate (22), and a set of letter profiles (25) which are matched precisely so that no tool other than a particularly designed card can open the lock. Lock (10) also has upper and lower housing members (11) and (12) and a shackle (50).
FIG. 3 illustrates the relationship between card (61) and lock (10) according to the present invention. When the card (61) is inserted into a card inserting slot (15) at the back of the lock (10), its front end abuts sliding plate (22), which in turn abuts point R on upper lock portion (11). Card (61) gets contacts three internal blocks (29) beneath the sliding plate (22) so that a plurality of, for example, three embossed letters (62) on the card (61) can contact their corresponding letter profiles (25) evenly. When the embossed letters (62) on the card (61) match the engraved letters (251) on the letter profiles (25), the card (61) can be pressed downwardly slightly so that the sliding plate (22) is displaced downwardly by the front edge of the card (61) retained by the point R at the sliding plate (22). Consequently, when the engraved letters (251) are filled by the embossed letters (62), depressing card (61) causes the letter profiles (25) to depress side levers (26) at both sides of the letter profiles (25) into their corresponding chambers (31) in retaining plates (30), respectively, and sliding plate (22) is lowered until its front edge is lower than a stop element (13) at on upper housing (11). The sliding block (21) can then be moved farther.
As shown in FIG. 4, when the sliding block (21) is moved forward, its front fork (211) pushes slant surface (42) on each of two sliding pieces (41) so that its longitudinal thrust is converted to traverse thrust by its movement on the slant surface (42). Hence, the two sliding pieces (41) which retain a shackle (50) at two side retaining notches (51) are retracted and disengaged from the retaining notches (51). The shackle (50) is then forced to move by compression spring (52), and the lock is opened.
FIG. 5 shows an alternative embodiment for the letter profiles (25) and the retaining plates (30). Due to changes in the shapes of the card (61), the letter profiles (25) and the retaining plates (30), use of the sliding plate (22) with its supporting posts (23) and springs (24) can be eliminated. As shown in FIGS. 6 and 7, after the card (61) with hollow letters (62) is inserted into the card inserting slot (15), the letter profiles (25) are depressed for a depth equal to the height of a upper stepped portion (252) of such embossed letters (251) on the letter profiles (25). Each side lever (26) then reaches the position Y in the chamber (31). Then, if the card (61) is pushed forward further, the embossed letters (251) on the letter profiles (25) will pop up into their corresponding hollow letters (62) on the card (61) until the uppers stepped portions (252) reach the card (61). The side levers (26) are located at the position X of the chambers (31). Consequently, the sliding block (21) can be pushed forward to open the lock. This design then which can prevent opening of; the lock by any tool other than the designated card. | A card-operated lock using a card with embossed letters matching with corresponding letters on letter profiles in the lock for lowering of side levers on the letter profiles and consequently disengaging the letter profiles from their retaining plates to open the lock. The lock is designed to prevent opening thereof without the designated card. | 4 |
FIELD OF THE INVENTION
The invention is concerned with a first responder system for predictively modeling contaminant transport during an environmental threat or a Chemical, Biological, or Radiological (CBR) threat or obscurant threat and for effective response after the threat.
DESCRIPTION OF THE PRIOR ART
The effective defense of cities, large bases, and military forces against chemical, biological, or radiological (CBR) incidents or attack requires new prediction/assessment technology to be successful. The existing plume prediction technology in use in much of the nation is based on Gaussian similarity solutions (“puffs” or “plumes”), an extended Lagrangian approximation that only really applies for large regions and flat terrain where large-scale vortex shedding from buildings, cliffs, or mountains is absent. These current plume methods are also not designed for terrorist situations where the input data about the source (or sources) is very scant and the spatial scales are so small that set-up, analysis and situation assessment of a problem must take place in seconds to be maximally effective. Both greater speed and greater accuracy are required.
The CBR defense of a fixed site or region has a number of important features that make it different from the predictive simulation of a contaminant plume from a known set of initial conditions. The biggest difference is that very little may be known about the source, perhaps not even its location. Therefore any analysis methods for real-time response cannot require this information. It is a crucial requirement to be able to use anecdotal information, qualitative data, and any quantitative sensor data we may be lucky enough to have and instantly build a situation assessment suitable for immediate action.
A software emergency assessment tool should be effectively instantaneous and easy to use because we require immediate assessment of new data, instantaneous computation of exposed and soon-to-be exposed regions, and the zero-delay evaluations of options for future actions. The software should also be capable of projecting optimal evacuation paths based on the current evolving situation assessment.
To meet these requirements, a new tool is required that is much faster than current “common use” models with accuracy comparable to three-dimensional, physics-based flow simulations for scenarios involving complex and urban landscapes. The focus is on situation assessment through sensor fusion of qualitative and incomplete data.
Typical hazard prediction and consequence assessment systems have at their heart a plume simulation model based on a Gaussian plume/puff model. These systems typically employ Gaussian plume simulation models and require accurate velocity fields as input. The Gaussian plume method, while relatively fast, tends to be inaccurate, especially for urban areas. The setup for all these systems tends to be complicated, and require a-priori knowledge of the source characteristics.
Some examples of common-use hazard prediction and assessment systems are as follows:
CATS (Consequences Assessment Tool Set) is a consequence management tool package, developed by the U.S. Defense Threat Reduction Agency, U.S. Federal Emergency management Agency, and Science Applications International Corp, that integrates hazard prediction, consequence assessment, emergency management tools, including the Hazard Prediction and Assessment Capability (HPAC) system, and critical population and infrastructure data within a commercial Geographical Information System. (CATS: Consequences Assessment Tool Set, U.S. Defense Threat Reduction Agency, U.S. Federal Emergency management Agency, and Science Applications International Corp.; SWIATEK et al. “Crisis Prediction Disaster Management, SAIC Science and Technology Trends II, Jun. 24, 1999)
CAMEO® (Computer Aided Management of Emergency Operations) is a system of software applications used widely to plan for and respond to chemical emergencies. It is one of the tools developed by EPA's Chemical Emergency Preparedness and Prevention Office (CEPPO) and the National Oceanic and Atmospheric Administration Office of Response and Restoration (NOAA), to assist front-line chemical emergency planners and responders. (CAMEO®: Computer Aided Management of Emergency Operations, EPA's Chemical Emergency Preparedness and Prevention Office (CEPPO) and NOAA; CAMEO “Computer Aided Management of Emergency Operations,” U.S. Environmental Protection Agency, May 2002, pp. 1-306)
MIDAS-AT™ (Meteorological Information and Dispersion Assessment System—Anti-Terrorism), a product of ABS Consulting Inc. is the all-in-one software technology that models dispersion of releases of industrial chemicals, chemical and biological agents, and radiological isotopes caused by accidents or intentional acts. MIDAS-AT is designed for use during emergencies and for planning emergency response drills. Its Graphical User Interface (GUI) is designed for straightforward user entry of information required to define a terrorist scenario with enough detail to provide critical hazard information during the incident. (MIDAS-AT™: Meteorological Information and Dispersion Assessment System—Anti-Terrorism: ABS Consulting)
HPAC (Hazard Prediction and Assessment Capability), developed by Defense Threat Reduction Agency, is a forward-deployable, counter proliferation-counterforce collateral assessment tool. It provides the means to predict the effects of hazardous material releases into the atmosphere and its impact on civilian and military populations. It models nuclear, biological, chemical, radiological and high explosive collateral effects resulting from conventional weapon strikes against enemy weapons of mass destructions production and storage facilities. The HPAC system also predicts downwind hazard areas resulting from a nuclear weapon strike or reactor accident and has the capability to model nuclear, chemical and biological weapon strikes or accidental releases. (HPAC: Hazard Prediction and Assessment Capability, DTRA, HPAC Version 2.0 and HASCAL/SCIPUFF Users Guide, Defense Special Weapons Agency, July 1996; “Hazard Prediction and Assessment Capability” Fact Sheet, Defense Threat Reduction Agency Public Affairs, pp. 1-2)
VLSTRACK (Vapor, Liquid, and Solid Tracking), developed by Naval Surface Warfare Center, provides approximate downwind hazard predictions for a wide range of chemical and biological agents and munitions of military interest. The program was developed to be user-friendly and features smart input windows that check input parameter combinations to ensure that a reasonable attack is being defined, and simple and informative output graphics that display the hazard footprint for agent deposition, dosage, or concentration. The model also features variable meteorology, allowing for interfacing the attack with a meteorological forecast; this feature is very important for biological and secondary evaporation computations. (VLSTRACK: Vapor, Liquid, and Solid Tracking, [U.S. Pat. No. 5,648,914] Naval Surface Warfare Center, Bauer, T. J. and R. L. Gibbs, 1998. NSWCDD/TR-98/62, “Software User's Manual for the Chemical/Biological Agent Vapor, Liquid, and Solid Tracking (VLSTRACK) Computer Model, Version 3.0,” Dahlgren, Va.: Systems Research and Technology Department, Naval Surface Warfare Center.)
ALOHA (Areal Locations of Hazardous Atmospheres), from EPA/NOAA and a component of CAMEO, is an atmospheric dispersion model used for evaluating releases of hazardous chemical vapors. ALOHA allows the user to estimate the downwind dispersion of a chemical cloud based on the toxicological/physical characteristics of the released chemical, atmospheric conditions, and specific circumstances of the release. Graphical outputs include a “cloud footprint” that can be plotted on maps to display the location of other facilities storing hazardous materials and vulnerable locations, such as hospitals and schools. (ALOHA®—Areal Locations of Hazardous Atmospheres, EPA/NOAA; “ALOHA Users Manual”, Computer Aided Management of Emergency Operations, August 1999, pp. 1-187)
FASTD-CT (FAST3D—Contaminant Transport) is a time-accurate, high-resolution, complex geometry computational fluid dynamics model developed by the Naval Research Laboratory in the Laboratory for Computational Physics and Fluid Dynamics. The fluid dynamics is performed with a fourth-order accurate implementation of a low-dissipation algorithm that sheds vortices from obstacles as small one cell in size. Particular care has been paid to the turbulence treatments since the turbulence in the urban canyons lofts ground-level contaminant up to where the faster horizontal airflow can transport it downward. FAST3D-CT has a number of physical processes specific to contaminant transport in urban areas such as solar chemical degradation, evaporation of airborne droplets, re-lofting of particles and ground evaporation of liquids. (FAST3D-CT: FAST3D—Contaminant Transport, LCP & FD, NRL Boris, J. “The Threat of Chemical and Biological Terrorism: Preparing a Response,” Computing in Science & Engineering, pp. 22-32, March/April 2002.)
NARAC (National Atmospheric Release Advisory Center) maintains a sophisticated Emergency Response System at its facility at Lawrence Livermore National Laboratory. The NARAC emergency response central modeling system consists of a coupled suite of meteorological and dispersion models that are more sophisticated than typical Gaussian models. Users access this system using a wide variety of tools, also supplied by NARAC. With this system NARAC provides an automated product for almost any type of hazardous atmospheric release anywhere in the world. Users must initiate a problem through a phone call to their operations staff or interactively via computer. NARAC will then execute sophisticated 3-D models to generate the requested products that depict the size and location of the plume, affected population, health risks, and proposed emergency responses. (NARAC: Atmospheric Release Advisory Capability, Lawrence Livermore National Laboratory, “Forewarning of Coming Hazards,” Science & Technology Review, pp. 4-11, June 1999, Lawrence Livermore National Laboratory.)
State-of-the-art, engineering-quality 3D predictions such as FAST3D-CT or the NARAC Emergency Response System that one might be more inclined to believe can take hours or days to set up, run, and analyze.
All of the above-mentioned systems take several minutes, hours, or even days to return results. Simplified systems such as PEAC® (Palmtop Emergency Action for Chemicals [U.S. Pat. No. 5,724,255] originally developed by Western Research Institute provide the necessary emergency response information to make quick and informed decisions to protect response personnel and the public. PEAC-WMD 2002 provides in hand information compiled from a number of references with very fast recall. PEAC provides emergency responders with instant access to vital information from a number of sources and evacuation distances based on several sets of guidelines. This system, can return results within seconds, requires less detailed knowledge of the source, but the resulting fixed-shape plume does not take into account any effect of complex terrain or buildings.
Waiting even one or two-minutes for each approximate scenario computation can be far too long for timely situation assessment as in the current common-use hazard prediction systems. Overly simplified results can result in inaccurate results. The answer to this dilemma is to do the best computations possible from state-of-the-art 3D simulations well ahead of time and capture their salient results in a way that can be recalled, manipulated, and displayed instantly.
SUMMARY OF THE INVENTION
Greater accuracy and much greater speed are possible at the same time in an emergency assessment system for an environmental threat or airborne chemical biological and radiological (CBR) threats. The present invention is a portable, entirely graphical hazard prediction software tool that exploits the new dispersion nomograph technology in order to achieve its speed and accuracy. The Nomograph technology has been filed as a provisional application at the U.S. Patent and Trademark Office, provisional application No. 60/443,530 on Jan. 30, 2003. The use of the dispersion nomograph representation and processing algorithms also allow some new features not available in existing systems. Multiple sensor fusion for instantaneous situation assessment is an automatic consequence of the nomograph technology. Reports from sensors about a contaminant can used to determine the affected area downwind. Using three or four appropriate sensor readings, the present invention can also backtrack and locate an unknown source graphically with zero computational delay. The present invention can accept qualitative and anecdotal input and does not require knowledge of a source location or a source amount.
The present invention provides an easy to use graphical user interface (GUI) to manipulate sensor, source, or site properties (i.e. location) and immediately provides an updated display of potential CBR hazards from a contaminant plume. The implementation has fast forward and fast reverse for the plume envelope displays, direct sensor fusion, and the ability to vary environmental properties in mid scenario. The present invention also plots evacuation routes automatically. The capability appears to the user as an infinite library of scenarios with a graphical controller to select, morph, and manipulate the CBR scenarios directly.
With the development of networked chemical sensors, and their possible deployment in cities and bases, it is vital to deploy them in optimal locations to provide the most beneficial effect. The characteristics of a sensor network, and the placement of sensors within the network, need to be evaluated for performance for a given situation. A sensor network should be capable of minimizing the detection delay of a source release. This maximizes the response time of people within the effected area, allowing them to take the appropriate measures to limit their exposure to the release.
The costs and logistics of running, building, and maintaining a sensor network makes it difficult to provide zero detection delay if point detectors are used exclusively. While some delay may be tolerated, the present invention minimizes this delay within other constraints of the situation. To find an optimal sensor network, the present invention uses a genetic algorithm using features of the present invention is an attractive solution.
An approach using genetic algorithms was selected for sensor optimization because the characteristics making up a robust sensor network were largely unknown. This approach also made it easy to modify specific characteristics while leaving the search method intact. Furthermore, advances in contaminant transport modeling made it possible for this search technique to be utilized.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing the overall structure, and main components of the present invention.
FIG. 2 is an Event Flow diagram illustrating how the components of the present invention respond to events generated internally, and externally.
FIG. 3 is a diagram representing the components of the graphical user interface of the present invention.
FIG. 4 is a diagram showing the presentation of Nomograph displays generated by the Nomograph library.
FIG. 5 is a detailed scenario using the present invention.
FIG. 6 is a block diagram of the various events generated externally, and internally in the present invention.
FIG. 7 shows a block diagram representing the main event loop, a component of the present invention to Nomograph Interface.
FIG. 8 is a functional block diagram of the interface used to communicate with the Nomograph libraries, a component of the present invention to Nomograph Interface.
FIG. 9 a is an exemplary Nomograph display of the upwind danger zone in accordance with the present invention.
FIG. 9 b is another exemplary Nomograph display of the upwind danger zone in accordance with the present invention.
FIG. 10 is a graph showing the fractional area covered versus number of sensors for detection delay of three, six, and nine minutes in accordance with the present invention.
FIG. 11 a is an exemplary Nomograph display showing 40 sensors within a domain in accordance with the present invention.
FIG. 11 b is an exemplary Nomograph display showing 10 sensors within a domain in accordance with the present invention.
FIGS. 12 a and 12 b are exemplary Nomograph displays showing plume envelopes for the release of two sources within a domain in accordance with the present invention.
FIG. 13 is a graph depicting the coverage of the sensor network versus a random sensor placement run for the same number of intervals in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Refer to FIG. 1 for the overall data flow of the invention. There are two main components to analyzer 1000 , the Graphical User Interface (GUI) 100 , and the Nomograph Interface 101 . This modular configuration allows manipulation either from analyzer 1000 , or an External Interface 107 . This flexibility enables analyzer 1000 to be a stand-alone system or as a component of larger command and control system. This modular approach is used throughout analyzer 1000 , which allows it to be flexible, robust, and easily extendable.
Nomograph Interface 101 translates from the data format used in GUI 100 , and External Interface 107 to the data format used by a Nomograph Library 102 . Within analyzer 1000 , the properties of each sensor, source, and site (SSS) are represented as an object. An object is defined as the set of properties that comprise a sensor, source or site. The number of properties for each sensor, source, or site object may vary, depending on what type of sensor, source, or site the object represents. Each SSS is represented as a state vector in Nomograph Library 102 . A state vector is defined as the properties Nomograph Library 102 uses for a sensor, source, or site to calculate a Nomograph Display 106 . An object will always have a corresponding state vector. The SSS objects will include at a minimum the properties represented by its corresponding state vector. An object may be modified by: 1) user of GUI 100 ; 2) by an outside program, script, network, or other connection via External Interface 107 ; or 3) by the reconciliation of the properties between an object and its state vector counterpart after a new set of Nomograph displays has been generated. Similarly, an environment object exists that contains the overall properties used by Nomograph Library 102 . Any changes 103 - 105 to a property of any object, made by External Interface 107 , or GUI 100 are reported to Nomograph Interface 101 . Depending on the object property changed, Nomograph Library 102 would be called, and new displays 106 would be generated. The change of a property of an object will send out a notification that the object has been changed to GUI 100 , and to External Interface 107 .
All SSS objects have the following properties, position of the object, and a property, which includes, or excludes the object from the generation of Nomograph Display 106 .
Sensor objects typically represent external sensors 203 (sensor in external mode). A sensor object in external mode will have most of its properties determined by a connection to a real sensor via External Interface 107 . The sensor state can be either hot or cold. A sensor in a hot state is defined as a sensor that has detected a contaminant at its location, while a sensor in a cold state has not. Sensor objects have all of the general properties of an object, along with additional properties depending on the type of sensor represented. This includes sensor modes, its current state, the timestamp of its last state change, the concentration, mass, type and other relevant properties of the contaminant detected. The additional sensor modes include manual, and simulation modes. A sensor object in manual mode has all of its properties determined by the user and are typically used for anecdotal reports entered by the user in GUI 100 . In the simulation mode, a sensor's state is determined by the contaminant plume as determined by Nomograph Library 102 . For example, sensors in simulation mode within the contaminant footprint will change its state from cold to hot, while a sensor in manual or external mode would not. Depending on the information provided by the external, or manual sensor, additional sensor states showing intermediate states between hot and cold might be represented by the sensor object. However, the additional sensor states would be translated into hot and cold states in the corresponding state vector depending on the sensitivity of the sensor network, and user preference. Multiple sensor objects could represent one real sensor. An example would be a mobile sensor taking sensor readings at fixed interval in time. Sensor objects can be grouped together. Examples of sensor groups include a sensor group for a fixed sensor network, and a sensor group for mobile sensors.
Source objects represent a contaminant release at a location. The number of properties can vary in a Source object. At a minimum, it has the general properties of a standard object. Additional properties can include the concentration, mass, type, and other relevant properties of the contaminant. These additional properties would increase the level of detail provided by Nomograph Displays 106 , but are not required. Multiple source objects can be grouped together to form other types of contaminant releases. This includes line sources.
Site objects represent a region, or area of interest. A site object is used to provide detailed properties about that area. They are typically used to generate additional Nomograph displays 106 specifically pertaining to that site. A site object has the general properties of a standard object. Additional properties could include building parameters, or other relevant information used to protect that site.
An environmental object exists for analyzer 1000 . The properties in an environmental object consist of temperature, time, season, wind speed, and direction, and other meteorological properties. These properties may be set by the user manually, or updated automatically via External Interface 107 .
Nomograph Library 102 takes the SSS state vectors, and the environmental vector as input and outputs Nomograph displays 106 . These state vectors only include the properties used to generate Nomograph display 106 . Properties common to SSS state vectors are its position, and a flag that allows the vector to be excluded from the calculation of Nomograph Displays 106 .
The sensor state vectors 109 consist of the current state, the timestamp of its last state change, its mode, the concentration, mass, type, and other relevant properties of the contaminant detected. Source state vector properties include the amount of contaminant released, timestamp of release, mass, type, and other relevant properties of the contaminant. Site state vectors contain the special properties pertaining to that site. The environmental state vector 108 consists of the time of day, season, current temperature, wind direction, and speed, and other meteorological properties.
The Nomograph Options 110 passed to Nomograph Library 102 include the requested size of Nomograph Display 106 , the selected area of the Nomograph, and which set of Nomograph tables to be used in the generation of Nomograph Display 106 .
A more detailed description of the invention is found in FIG. 2 which depicts the event flow between GUI 100 , External Interface 107 , and Nomograph Interface 101 . An event is defined as a notice communicated to a component of analyzer 1000 that an object, or a component of analyzer 1000 has been modified. Upon receipt of an event, the recipient will take the appropriate action. For example, if a user changes a manual sensor's state from cold to hot, the sensor object would post a SSS Altered event ( FIG. 6 , 602 ). This is received by Nomograph Interface 101 , which calls Nomograph Library 102 to generate an updated Nomograph Display 106 . Nomograph Interface 101 would then post an event notifying GUI 100 that an updated Nomograph Display 106 is available. If necessary, this change will be shown to a user. The use of events in analyzer 1000 allow for uniform handling of internal and external changes. This allows objects, and components of analyzer 1000 to synchronized regardless of the source of the change, internal or external.
Nomograph Interface 101 receives events from the components of analyzer 1000 , and from all the objects in analyzer 1000 . A change in a property of an object from any component of analyzer 1000 would be sent to Nomograph Interface 101 . From this component, other objects and components would be notified of the change via events. Examples of actions from Nomograph Interface 101 that post events are: 1) a modification of an SSS object, or the environmental object by External Interface 107 or GUI 100 , 2) modification of a SSS object, or the Environmental object after a reconciliation of an object with its corresponding state vector after the generation of an updated Nomograph Display 106 . Depending on the type of event received, Nomograph Interface 101 will call Nomograph Library 102 to generate a new Nomograph Display 106 , or will wait some period of time for more events to arrive before updating Nomograph Display 106 .
GUI 100 posts events through actions of the user, and reacts to events from Nomograph Interface 101 . Examples of user actions that generate events through GUI 100 are: 1) the addition or removal of SSS objects, 2) A modification of a property of an SSS object, 3) modification of properties in the Environment object, 4) saving/loading of SSS objects and the Environmental object from a storage device, 5) a change in how Nomograph Displays 106 are presented, 6) changing the set of nomograph tables used to generate Nomograph Displays 106 . The events that GUI 100 reacts to are changes in the properties of SSS objects, changes to properties in the environment object, and updates to Nomograph Displays 106 .
External Interface 107 posts events through changes to SSS objects, and the environment object via connections 203 to External Interface 107 . External Connections 203 to External Interface 107 typically include sensors, meteorological information, an external program, or network connections. External Interface 107 reacts to events from Nomograph Interface 101 . Examples of actions from External Interface 107 that generate events are: 1) modifying a property of a SSS objects, 2) modifying a property of the environmental object, 3) a generation of updated Nomograph Displays 106 .
As shown in FIG. 3 , the user and monitor of Chemical, Biological or Radiological Attacks interacts with present invention through a graphical user interface. GUI 100 displays the SSS objects as graphical elements. GUI 100 is one of the key components of analyzer 1000 , through which the user ( FIG. 2 , 200 ) interacts with analyzer 1000 . The simplicity, and ease of use of GUI 100 is in stark contrast to other emergency response systems. The user has to merely point and click to manipulate properties of SSS objects, or environmental properties. The user is not required to input detailed information about the contaminant prior to obtaining a useful result. Additional information can be added as it becomes available. Because of its simplicity of use, training in the use of analyzer 1000 is minimal.
Using GUI 100 , the user can add, remove, or modify the properties of the SSS objects. The various environmental properties can also be modified 302 . The user may also load, and save scenarios, run simulations, and change how Nomograph Displays 106 are presented 303 . GUI 100 translates Nomograph Displays 106 into a display format 300 , which is viewable by the user. This includes translating Nomograph Displays 106 into the required coordinate system, adding maps, or other graphical layers ( FIG. 1 , 111 ) representing buildings, terrain features, or other relevant geographical information about the area ( FIG. 1 , 111 ), and merging the selected Nomograph Displays 106 into an image, or images.
The graphical representation of each object is dependant on some or all of its properties 304 - 307 . For example, a source object that is included in the Nomograph generation is depicted as a star 304 . Sensor objects are depicted using different colors and shapes, depending on their properties. Examples of sensor depictions are shown 305 - 307 . For instance, a simulation sensor 305 , in a hot state, which is included in the generation of Nomograph Display 106 , is easily identified from a manual sensor 306 , whose state is cold, which is also used in the generation of Nomograph Display 106 .
GUI 100 can provide multiple views of SSS objects, or the environment object. For example, a sensor object 306 is depicted in a main GUI 300 and an auxiliary GUI 301 . Main GUI 300 is used to display some information about all of the objects on the screen, as well as a presentation of Nomograph Displays 106 . Auxiliary GUI 301 is used to present the properties in an object in a different, or expanded format. Auxiliary GUI 301 may display the same information as main GUI 300 , but typically shows more detail about one or more SSS objects, the Environment object, or the Nomograph Options. Multiple auxiliary GUI's may be used depending on user preference. In this figure, two portions of the auxiliary display are shown, a GUI portion 302 to control the environment object's properties, and an auxiliary GUI portion 303 to control the Nomograph Options.
FIG. 4 shows diagrams of the main Nomograph Displays 106 generated by Nomograph Library 102 . This figure shows some of the unique diagnostic capabilities of analyzer 1000 . For example, the Backtrack display 401 is unique to analyzer 1000 due to the use of Nomograph Library 102 . The speed with which the displays are generated contribute to the usefulness of analyzer 1000 .
The Nomograph tables used to generate Nomograph Displays 106 are typically selected based on the properties of the state vector, and the area of interest. The main types of Nomograph tables generated are 1) the consequence display 400 , 2) the backtrack display 401 , 3) the footprint display 402 , 4) the simulation display 403 , 5) escape display 404 , 6) danger zone display 405 , and 7) the leakage display 406 . Nomograph Library 102 may generate specialized displays for a particular state vector, if requested.
Sensor vector states are used to generate two types of Nomograph Displays 106 , consequence and backtrack displays. The consequence display 401 consists of a region downwind, with an upwind safety radius from a sensor that could potentially be exposed to a contaminant. This is dependant on the whether the sensors states are hot or cold. The Backtrack display 402 shows the probability of a contaminant source location for different regions. The Backtrack display will display regions by different values, depending on the probability that a source originated from that area.
Source vector states are used to generate simulation 403 , footprint 402 , and escape route 404 displays. The footprint display shows the area downwind, with an upwind safety radius that could become exposed to the contaminant from the source. The simulation display shows a time evolution of a plume. The escape display shows the optimal escape routes, based on the footprint display from the source.
Site vector states are used to generate danger zone 405 , and leakage 406 displays. The danger zone display shows the area upwind from a site where a contaminant placed in that area could reach the site. The leakage display shows the area downwind of the site that could potentially be exposed to a contaminant if the site itself was exposed.
FIG. 5 is a block diagram detailing a user's response to information displayed by analyzer 1000 . In this scenario, a chemical agent has been released in an urban environment 500 . A fixed sensor net has been deployed in the urban area, and several of the sensors alarm 501 indicating that a chemical release has occurred in the area. The sensors are connected to External Interface 107 , and their change in status is received 502 . Nomograph Display 106 is generated 503 , which is displayed by GUI 100 , which also shows the change in status of the effected sensors. The user sees the change in state, and selects backtrack display 303 from GUI 100 . Sensor readings can also be obtained from mobile sensors, or other sources like first responder radio reports, or people becoming ill from the chemical release. If this information exists 505 , it can be entered into analyzer 1000 as a manual sensor reading 510 .
If any manual sensors, or automatic sensors are hindering the ability of analyzer 1000 to limit an area where the chemical release has occurred, the user can exclude 506 the sensor readings from the backtrack. The user can now determine if they have enough information to determine where the source is located 507 . If the backtrack area displayed by analyzer 1000 is not narrowed to a small region, the user has several options. They can wait for more information to come in via the fixed sensor network, or by manual sensor input 508 . They can also send mobile sensors to the potential chemical source area displayed by the backtrack 509 , with the goal of finding the edges of the chemical plume.
When the backtrack display from analyzer 1000 has narrowed the location of the chemical release to a small region, a source object can be placed in the backtrack region 511 . With the source object displayed in analyzer 1000 , the area downwind that could be contaminated by the chemical release is known. The user can now setup escape routes based on the source object 512 , and send out this information out to areas downwind of the source 513 . The escape route information can be sent out to remote sites via External Interface 107 of analyzer 1000 , or through other methods external to analyzer 1000 .
FIG. 6 is a functional block diagram showing the creation of events typically created in analyzer 1000 . These events are routed through analyzer 1000 to Nomograph Interface 101 to other components in analyzer 1000 . An event may affect multiple components of analyzer 1000 , or none at all.
Environmental Objects usually generate events by changing environmental parameters 600 , or changing the Nomograph tables used 601 . Changing the environment parameters generates a metEvent 606 . The environment parameters that are most frequently altered are the wind direction, and velocity 604 . Other miscellaneous parameters 605 that would generate a metEvent include time of day, season, and weather conditions, and other meteorological parameters. Changing the nomograph tables used or a change in the location viewed analyzer 1000 608 , will generate an areaEvent.
The two types of events that occur with Sensor, Source, or Site objects are a change in the properties of an SSS object 602 , and the addition/removal of an SSS object 603 . Changing a property of an SSS object 609 will generate an SSS Object Event 610 . The properties that typically create an SSS Object Event include altering the objects location, the type of object it represents, whether it is included in the calculation of Nomograph Displays 106 , and its state. Adding or removing an SSS Object 611 will generate an SSS Add/Remove Object Event 612 .
FIG. 7 is a functional block diagram of the Event Loop. This is an internal component of Nomograph Interface 101 . The Event Loops is started 700 when Nomograph Interface 101 is initialized. It first checks see if any SSS events have occurred 701 . If an SSS event was generated, it is checked to determined what type of event it is 706 - 707 , and sets the updateFlag to true if the event is valid. If an environment object event has occurred 702 , a new nomograph table will be loaded depending of the parameters of the Environmental object 709 , and the updateFlag will be set. If the updateFlag has been set 703 , the NG Interface will be called 711 , which will update Nomograph Displays 106 . If the program hasn't finished, it will continuously process this loop 704 , otherwise the loop will exit 705 .
FIG. 8 is a functional block diagram of the NG Interface. This is an internal component of Nomograph Interface 101 , which translates the SSS objects, and Environmental objects into the format that Nomograph Library 102 can use, and outputs updated SSS objects, and updated Nomograph Displays 106 .
First, the SSS objects, and the Environmental object are converted into their state vector equivalent 800 - 801 . Next, Nomograph Library 102 is called, and new Nomograph Displays 106 are generated 802 . Since Nomograph Library 102 can potentially alter the state vectors, each vector is checked to see if it has been altered 803 - 805 . If it has been altered, the SSS object and SSS vector are reconciled by updating the properties of the SSS object using the properties from the state vector 807 . New Nomograph Displays 106 are sent out to the other components of analyzer 1000 806 , and the NG Interface returns.
To maximize accuracy and speed in assessing an environmental threat or airborne CBR threat within a domain, e.g., a city, the city should be saturated with sensors. Such a system may be impractical with respect to financial budgets and data management. Therefore, it is a goal to optimize sensor placement based on a usable number of sensors that fit a particular financial budget and data management system. To find an optimal sensor network, a genetic algorithm using features of the present invention provides this ability.
Since its development in the 1960's, the genetic algorithm has been used successfully in many different fields. Genetic algorithms are a type of search algorithm that works particularly well if the search space is too large to run every potential case and when local maxima exist. For example, to exhaustively search every possible location of a group of 20 sensors in a grid of 350×350 potential locations at a rate of 20 evaluations per second would take months if not years. While the answer generated by a genetic algorithm might not be the best solution, it will typically be a very close approximation to it. The main disadvantage of genetic algorithms is that they potentially require a lot of time and computing resources, depending on the rate of convergence and the computational cost of a fitness function. However, given the amount of time required to evaluate a typical population, many examples of parallelized genetic algorithms exist.
A genetic algorithm evaluates the fitness of genomes in a population, and generates the next population based on the fitness of the previous generation. Each genome is a potential solution to the problem, where the elements of the solution are equivalent to chromosomes in the genome. The initial population is usually chosen randomly, but the initial population can also be seeded with solutions that are known to produce good results. The next population of genomes is determined by combining members of the current population to produce offspring that are based on the scores of each parent genome's fitness function. This is known as crossover. During crossover, individual chromosomes within the offspring can potentially mutate, giving the offspring slightly different characteristics that are unique from its parents. This is particularly useful in later generations of the population, where the population is fairly homogeneous. The user determines the fitness function of a genome, in which the performance of a genome is evaluated, and a fitness score is assigned. Members with a high fitness score will typically have many offspring in the next generation while those with a low fitness score could have few or none. New populations are generated, and evaluated until one of several requirements is met. This includes the desired fitness level of a member of the population, the average fitness of the population has reached some level, or the maximum number of generations has been calculated.
An approach using genetic algorithms was selected for sensor optimization because the characteristics making up a robust sensor network were largely unknown. This approach also made it easy to modify specific characteristics while leaving the search method intact. Furthermore, advances in contaminant transport modeling made it possible for this search technique to be utilized.
The use of computational fluid dynamics models or Gaussian plume models are not suitable for use as the fitness evaluation of a genetic algorithm due to their relatively long times to generate plumes, and the sheer number (many millions) of fitness evaluations and iterations required for a solution to converge. Even if the time to generate a Gaussian plume decreased significantly, the plumes generated would not take into account the 3 D geometry of an urban region. The plume capability of analyzer 1000 is well-suited for this type of evaluation because it produces plumes comparable to the computational fluid dynamics calculation as stated above while producing this result in about one millionth of the time. The speed of analyzer 1000 allows fitness functions to be evaluated for performance quickly. Table 1 shows the approximate amount of time required to run a genetic algorithm for 1000 generations using various plume models.
TABLE 1
Approximate time to run a fitness
evaluation for 1000 generations
Plume model
Computer
(population = 1000)
CFD(FAST3D-CT)
Supercomputer
~9000 hours (random sources)
Gaussian
Workstation
~500 hours (random sources)
Present
Laptop
~33 hours (random sources)
Invention
Present
Laptop
~4 hours (time dependent
Invention
sensor coverage, 20 sensors)
A genetic algorithm has been used where the members of the population with the highest fitness scores were kept in the next population. This ensures that the population's maximum fitness score will not decrease and also reduces the number of generations required to converge to an answer. The rate of crossover was set at 0.95 with the rate of mutation set at 0.25 percent, where the mutation increased if the rate of convergence decreased by a threshold. In one example, the genome was the set of locations of the sensors in the sensor network with the chromosomes consisting of (x, y) coordinates of the sensors. The population size was set to 1000. While the individual fitness function is now relatively fast, the algorithm was distributed over multiple processors using a message passing interface. The evaluations of the population are spread out over multiple processors, with the best results of a generation saved as candidates for the solution. This algorithm is computer bound so a high-speed interconnect is not necessary. Several different approaches were examined for the fitness function.
The first approach uses a plume model to generate plumes from randomly placed sources and then analyzes the sensor network's ability to detect the plume within time t of release. In this case, if a least one sensor is located within the plume, it counts as a detection of the plume. The sensor network individually evaluates a sequence of randomly located sources, with the fitness score based on the total number of sources detected. A new set of random sources must be calculated for each generation. If the set of source locations is fixed, the sensor network's solution would converge on the coverage of that set of fixed sources, but not on a optimal coverage of sources located anywhere in the region. This method has the advantage of being able to use a variety of plume prediction tools like Gaussian plume models, computational fluid dynamics models (e.g. FAST3D-CT), and Dispersion Nomograph tools (e.g. analyzer 1000 ). However analyzer 1000 is the best choice due to its speed and accuracy (Table 1, lines 1-3).
While this approach is acceptable, a much more efficient procedure was developed using the unique upwind capability of analyzer 1000 . FIG. 9 a is an exemplary Nomograph display 900 of the upwind danger zone in accordance with the present invention. In the figure, display 900 of a portion of a city, i.e., the domain, includes buildings, roads and trees. Display 900 additionally includes a site 902 of a sensor. The corresponding upwind zone 904 for the sensor at site 902 represents the upwind area where the contaminant from a source could hit the sensor. This upwind, probable source zone or “backtrack” zone is time-dependent and can also be described as an “anti-plume”. Sensor coverage is the union of the “anti-plumes” for all of the sensors in the region. FIG. 9 b illustrates this updated display. Specifically, FIG. 9 b is an exemplary Nomograph display 906 of the upwind danger zone in accordance with the present invention. In the figure, display 906 is of the same portion of the city as display 900 . Display 906 additionally includes a site 908 of a first sensor and a site 910 of a second sensor. The corresponding upwind zone 912 for the sensor at site 908 represents the upwind area where the contaminant from a first source could hit the first sensor, whereas the corresponding upwind zone 914 for the sensor at site 910 represents the upwind area where the contaminant from a second source could hit the second sensor. Using the union of anti-plumes as the fitness function decreases the time to evaluate a sensor network for a region drastically (see Table 1, line 4). The new fitness function is now the total area of sensor coverage for a given region ranging from zero to one, which could be calculated with a single call to analyzer 1000 .
Because of the increase in efficiency, the second approach was selected for the main optimization trials. To determine the optimal amount of sensors required for this region, sensor networks from five to forty sensors, in five sensor number increments were evaluated for total sensor coverage on a 2 km by 2 km region for a typical city. The wind was from the northwest, with a speed of three meters per second. The region itself is an urban area with varying degrees of building density ranging from open areas free of structures to city blocks with high building density. A dispersion nomograph utilized for this region was generated using FAST3D-CT, which includes all of the effects of buildings, streets, trees, etc. Analyzer 1000 is used to evaluate sensor configurations for a detection delay of three minutes, six minutes, and nine minutes. These times were selected based on results obtained from the walk away program. Nine minutes warning delay has been found to be maximum delay to be tolerated if at least 50% of a population in an area affected by a moderately large plume is to be saved.
FIG. 10 shows the fractional area covered versus number of sensors for detection delay of three, six, and nine minutes. The number of sensors required producing adequate coverage increases significantly as the plumes size decreases. Only 10 to 15 sensors are required to obtain 90% coverage for a nine-minute time delay, contrasted with over 40 for a three-minute detection delay. Even with 50 sensors, complete coverage of the region cannot be obtained for the three-minute delay while additional sensors became completely redundant past 30 sensors for these six- and nine-minute warnings.
FIGS. 11 a and 11 b are exemplary Nomograph displays 1100 and 1104 , respectively, of the same portion of the city as display 900 . FIGS. 11 a and 11 b represent the minimal sensor network required to detect at least 90% of the region for three- and nine-minute detection delays. For a nine-minute delay ( FIG. 11 b ), sensors are placed at sites 1106 towards the edge of the region, opposite of the wind direction because at nine minutes the “anti-plumes” are very large, and sensors are wasted if they are placed further upwind. If the time delay for detecting a plume is increased beyond nine minutes, the eventual result is a sensor network with all of the sensors placed along the edge of the domain. 40 sensors are required To provide the same coverage for a three-minute detection delay, 40 sensors at sites 1102 must be provided as illustrates in FIG. 11 a . The density of sensors for a given area in the region varied. More sensors were required for relatively open areas and where the plume funneled through gaps between buildings. This was particularly noticeable when the time delay allowed for detecting plumes was short.
The shape of the plume envelope can explain this result. In areas with few buildings, the plume envelopes are narrow and elongated, looking very much like their Gaussian plume counterparts. In areas with many buildings, the shape of the plume envelope is broader, depending on the geometry of the buildings and wind angle. FIGS. 12 a and 12 b are exemplary Nomograph displays 1200 and 1210 , respectively, of the same portion of the city as display 900 . FIGS. 12 a and 12 b depict plume envelopes for the release of two sources at sites 1202 and 1204 , respectively, in the domain after three and after nine minutes. The first source is released at site 1202 , which is in an open region, while the second source is released at site 1204 , which is in an area with high building density. Note that a plume 1208 illustrated in FIG. 12 a develops into plume 1214 in FIG. 12 b , whereas plume 1206 illustrated in FIG. 12 a develops into plume 1212 in FIG. 12 b . Plume 1214 has a shape that starts to change at point 1216 as it encounters a city block with high building density 1218 . In order to detect a narrow plume more sensors are required.
FIG. 13 is a graph that shows the coverage of the sensor network versus a random sensor placement run for the same number of intervals. The random (brute force) sensor placement is evaluated in the same manner as the genetic algorithm with the best candidate produced of each generation reported as the maximum coverage attained. For the same amount of effort, here two million calls to analyzer 1000 , the generic algorithm covered over 90% of the region while the random-placement approach's best answer results in coverage of about 72% of the region.
The use of a genetic algorithm to produce a plausible and useful sensor optimization has been shown. This approach was not possible until the low-latency evaluation of contaminated regions of analyzer 1000 was developed. To calculate 1000 generations requires 1 million calls to analyzer 1000 and many millions of individual sensor backtrack “anti-plume” evaluations. With more complex fitness functions, and more stringent requirements for a sensor network, the time to calculate an optimal network will only increase. Use of other plume models is prohibitive. This approach is one technique for determining the optimal sensor placement. It has also shown that to provide guaranteed short detection delays will require many sensors.
Although this invention has been described in relation to an exemplary embodiment thereof, it will be understood by those skilled in the art that still other variations and modifications can be affected in the preferred embodiment without detracting from the scope and spirit of the invention as described in the claims. | Networked groups of sensors that detect Chemical, Biological, and Radiological (CBR) threats are being developed to defend cities and military bases. Due to the high cost and maintenance of these sensors, the number of sensors deployed is limited. It is vital for the sensors to be deployed in optimal locations for these sensors to be effectively used to analyze the scope of the threat. A genetic algorithm, along with instantaneous plume prediction capabilities meets these goals. An analyzer's time dependant plumes, upwind danger zone, and sensor capabilities are used to determine the fitness of sensor networks generated by the genetic algorithm. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a power supply device for a vehicle, and more particularly, to a power supply device for a vehicle to be mounted in an idling-stop vehicle which temporarily stops the engine automatically when the vehicle comes to a stop, such as at a traffic light.
2. Description of the Related Art
In recent years, idling-stop vehicles that temporarily stop the engine automatically when the vehicles come to a stop, such as at a traffic light, have been used to reduce fuel consumption and emissions.
In a vehicle of this type, the engine is automatically stopped based on predetermined idling determination information such as the vehicle speed or the degree of opening of the accelerator when the vehicle is presumed to have stopped, and then automatically started by the starter in order to prepare the vehicle to start moving when an engine start condition indicating that the driver wants to start moving is satisfied.
In general, since the starter for starting an engine consumes a large amount of power, a phenomenon of a temporary drop in the voltage of a battery output system at the moment of starting the engine may occur.
Such a phenomenon becomes significant especially when a battery used as the power source is heavily discharged due to street driving in which stopping and starting of movement are frequently repeated.
When such a voltage drop occurs, problems, such as resetting of microcomputers used in electrical equipment in the vehicle, thereby losing memory contents, such as contents that have been learned up to that time, or temporary dimming of the instrument lighting or other lighting, thereby severely impairing the quality feeling of the vehicle, may occur.
Therefore, a configuration has been disclosed in which a boosting circuit for voltage compensation is provided in an idling-stop vehicle in order to prevent a voltage drop in the battery output system during restarting of the engine, and the boosting circuit is operated during a period in which the starter is operating upon starting of the engine (see, for example, Japanese Unexamined Patent Application Publication No. 2005-237149).
In addition, since a battery can be replaced by the owner, there may be a possibility of the polarities thereof being erroneously connected. Therefore, a protection circuit that prevents current from flowing when a reverse connection is made has been disclosed in, for example, Japanese Unexamined Patent Application Publication No. 2-197441.
A method for forming a protection circuit that prevents current from flowing when the polarities of a battery are mistakenly connected in reverse in a circuit that compensates, by using a boosting converter, for an output voltage drop due to a large power consumption of the starter during restarting of the engine as described above will be explained with reference to FIGS. 7 and 8 .
FIG. 7 illustrates a configuration including a battery 1 provided as a DC power source, a first load 6 , a first capacitor 2 , a boosting converter circuit 3 , a control circuit 4 which controls the boosting converter circuit 3 and a connector 5 to which the output voltage of the boosting converter circuit 3 is supplied, wherein the connecter 5 is connected to a second load (not shown).
The first load 6 includes a starter 61 , an engine 62 , and a generator 63 . The starter 61 is supplied with DC voltage from the battery 1 during starting of the engine in order to start the engine 62 . When the engine starts, power is generated by the generator 63 by using rotation as a power source in order to charge the battery 1 .
The boosting converter circuit 3 includes an inductor 31 , a first semiconductor switching element 32 defined by a field-effect transistor or other suitable semiconductor element, a first diode 34 and a second capacitor 35 . The inductor 31 and the first semiconductor switching element 32 are connected in series to the ends of the battery 1 . The anode of the first diode 34 is connected to the connection point between the inductor 31 and the first semiconductor switching element 32 , and the cathode of the first diode 34 is connected to an output terminal of the connector 5 . The second capacitor 35 is connected to the ends of the connector 5 .
With automobiles, it is often the case that the battery 1 can be replaced by the user. Therefore, it is necessary to provide, in the power supply device for a vehicle, a protection circuit that prevents current from flowing in the reverse direction when the user mistakenly connects the polarities of the battery 1 in reverse. In order to provide such a function, a relay switch 8 shown in FIG. 7 or a third diode 9 shown in FIG. 8 , for example, may be used to enable conduction only when a forward current flows. However, there is a problem in that when the output current of the power supply device for a vehicle is extremely large, the forward power loss of the third diode 9 or the power consumption of the relay switch 8 becomes too large to ignore, which causes the battery life to be shortened.
In addition, since the vehicle weight is large for large vehicles that are equipped with power steering devices, a high power is required for a motor used in the power steering device, and therefore the size of the motor must be increased. In order to prevent such an increase, a voltage greater than the output voltage (12 V) of an existing lead acid battery may be required. However, even in this case, a large current flows, and the loss cannot be ignored in an existing power supply device using a diode or a relay switch.
SUMMARY OF THE INVENTION
To overcome the problems described above, a power supply device for a vehicle according to a preferred embodiment of the present invention preferably includes a boosting converter circuit connected to a DC power source, a voltage detection circuit arranged to detect an output voltage of the DC power source, and a control circuit arranged to drive the boosting converter circuit in accordance with the output voltage detected by the voltage detection circuit so as to set the output voltage to a predetermined value. In the boosting converter circuit, a series circuit including at least one inductor and two semiconductor switching elements serially connected to one another is preferably connected to the ends of the DC power source. The boosting converter circuit preferably includes at least one rectifying element connected to a connection point between the at least one inductor and the two semiconductor switching elements serially connected to one another. The boosting converter circuit preferably includes at least one capacitor connected in parallel to the two semiconductor switching elements serially connected to one another. The two semiconductor switching elements are preferably serially connected such that the polarities of respective body diodes thereof are opposite to each other.
In the power supply device for a vehicle, preferably, the control circuit controls the boosting converter circuit such that the output voltage of the boosting converter circuit becomes the output voltage of the DC power source when a load connected to the DC power source is in an overloaded state and the output voltage of the DC power source is transiently dropped.
In the power supply device for a vehicle, preferably, a load of the boosting converter circuit is a power steering device, and the control circuit controls the output voltage of the boosting converter circuit in accordance with rotation angle information of steering in the power steering device.
In the power supply device for a vehicle, preferably, both of the two semiconductor switching elements are N-channel MOSFETs, and drain terminals thereof or source terminals thereof are connected to each other.
In the power supply device for a vehicle, preferably, the semiconductor switching element on a low-voltage side of the two semiconductor switching elements is controlled by the control circuit and the semiconductor switching element on a high-voltage side is configured as a self-driven type element including a diode arranged to apply a bias voltage to a control terminal.
According to various preferred embodiments of the present invention, in the power supply device for a vehicle including the boosting converter circuit that compensates a voltage drop of the battery due to a transient increase in load and supplies a voltage higher than the battery supply voltage, a circuit that prevents current from flowing in the reverse direction when the polarities of the battery are mistakenly connected in reverse can be provided with a low loss.
In addition, a mechanical switch, such as a relay switch, is no longer required when two FET body diodes are arranged such that the polarities thereof are opposite to each other, such that spark generation and noise generation are prevented.
The above and other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram illustrating a first preferred embodiment of the present invention.
FIG. 2 is a circuit diagram showing a case in which a battery is correctly connected in the first preferred embodiment of the present invention.
FIG. 3 is a circuit diagram showing a case in which a battery is reversely connected in the first preferred embodiment of the present invention.
FIG. 4 is a circuit diagram illustrating a second preferred embodiment of the present invention.
FIG. 5 is a circuit diagram illustrating a third preferred embodiment of the present invention.
FIG. 6 is a circuit diagram illustrating a fourth preferred embodiment of the present invention.
FIG. 7 is a circuit diagram of a power supply device for a vehicle for preventing reverse connection of a battery according to the related art.
FIG. 8 is a circuit diagram of another power supply device for a vehicle for preventing reverse connection of a battery according to the related art.
FIG. 9 is a circuit diagram illustrating a modification of the first preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will be explained in detail with reference to the drawings. The same or similar components and elements are denoted by the same reference characters, and the explanation thereof will essentially not be repeated.
First Preferred Embodiment
FIG. 1 is a circuit diagram illustrating a configuration of a power supply device for a vehicle according to a first preferred embodiment of the present invention.
In FIG. 1 , the power supply device for a vehicle preferably includes a battery 1 provided as a DC power source, a first load 6 , a first capacitor 2 , a boosting converter circuit 3 , a control circuit 4 which controls the boosting converter circuit 3 , and a connector 5 to which the output voltage of the boosting converter circuit 3 is supplied. A second load (not shown) is connected to the connecter 5 .
The first load 6 preferably includes a starter 61 , an engine 62 , and a generator 63 . The starter 61 is supplied with DC voltage from the battery 1 during starting of the engine in order to start the engine 62 . When the engine starts, power is generated by the generator 63 by using rotation as a power source, and charges the battery 1 .
The boosting converter circuit 3 preferably includes an inductor 31 , a first semiconductor switching element 32 , and a second semiconductor switching element 33 defined by a field-effect transistor (MOSFET) or other suitable semiconductor element, a first diode 34 , a second capacitor 35 , a second diode 36 , a bias resistor 37 , and a discharge resistor 38 . The inductor 31 , the second semiconductor switching element 33 , and the first semiconductor switching element 32 are preferably connected in series to the ends of the battery 1 . The drains of the first semiconductor switching element 32 and the second semiconductor switching element 33 are preferably connected such that the polarities of respective body diodes 321 and 331 are opposite to each other. Preferably, the anode of the first diode 34 is connected to the connection point between the inductor 31 and the second semiconductor switching element 33 , and the cathode of the first diode 34 is connected to an output terminal of the connector 5 . The second capacitor 35 is preferably connected to the ends of the connector 5 .
The second diode 36 with the anode thereof connected to the connection point between the first capacitor 2 and the inductor 31 and the cathode thereof connected to the gate terminal of the second semiconductor switching element 33 via the bias resistor 37 , and the discharge resistor 38 connected between the gate and the source of the second semiconductor switching element 33 , are preferably provided. The control circuit 4 monitors an input voltage supplied from the battery 1 and an output voltage by using an output voltage detection circuit 7 to control on/off of the first semiconductor switching element 32 such that an output voltage to be supplied to the second load has a predetermined value.
When the load connected to the battery 1 (DC power source) is in an overloaded state and the voltage of the DC power source transiently drops, the control circuit 4 controls the boosting converter circuit 3 such that the output voltage of the boosting converter circuit 3 has the voltage of the DC power source.
FIG. 2 is a circuit block diagram showing a case in which the polarities of the battery 1 are correctly connected. The first load 6 including the starter 61 , the engine 62 , and generator 63 in FIG. 1 is not shown since the first load 6 has no direct role in the operation.
When DC voltage is supplied from the battery 1 and the control circuit 4 applies the voltage to the gate terminal of the first semiconductor switching element 32 to turn on the first semiconductor switching element 32 , current flows in the inductor 31 , thereby generating the voltage between the ends of the inductor 31 . This turns on the second diode 36 , and the voltage is applied to the gate terminal of the second semiconductor switching element 33 via the bias resistor 37 , thereby also turning on the second semiconductor switching element 33 . In this manner, a current flows in a closed loop from the positive terminal of the battery 1 to the inductor 31 , the second semiconductor switching element 33 , the first semiconductor switching element 32 , and to the negative terminal of the battery 1 .
Subsequently, when the first semiconductor switching element 32 is turned off by a control signal from the control circuit 4 , energy accumulated in the inductor 31 during an ON period is released via the first diode 34 to charge the second capacitor 35 . In this manner, a current flows in a closed loop from the positive terminal of the battery 1 to the inductor 31 , the first diode 34 , the second capacitor 35 , and to the negative terminal of the battery 1 .
Next, in FIG. 3 , a case in which the polarities of the battery 1 are mistakenly connected in reverse is assumed. FIG. 3 is a circuit block diagram showing the case where the polarities of the battery 1 are connected in reverse.
When the battery 1 is reversely connected, the body diode 321 of the first semiconductor switching element 32 is biased in the forward direction, and thus is turned on. However, the body diode 331 of the second semiconductor switching element 33 is biased in the reverse direction, and thus is not turned on. That is, the two semiconductor switching elements ( 32 and 33 ) are used as a switch of the boosting converter circuit 3 , and are serially connected such that the polarities of the body diodes ( 321 and 331 ) thereof are opposite to each other, whereby current can be prevented from flowing in the boosting converter circuit 3 when the polarities of the battery 1 are mistakenly connected in reverse. Consequently, damage and malfunction of the load connected to the output of the boosting converter circuit 3 are prevented.
In this case, the second semiconductor switching element 33 is preferably configured as a self-driven type element in which the second semiconductor switching element is not controlled by the control circuit 4 since the second diode 36 is present, and is always turned on when the battery 1 is correctly connected thereto and always turned off when the polarities of the battery 1 are mistakenly connected in reverse.
In addition, to compensate for a transient drop of the supply voltage of the battery 1 upon starting of the starter 61 as described above, the output voltage of the boosting converter circuit 3 may preferably be set so as to be equal or substantially equal to or greater than the supply voltage of the battery 1 .
Furthermore, as shown in FIG. 9 , when the power supply device for a vehicle is used in the power steering device of a vehicle having a heavy vehicle weight, since stress is required to be controlled in accordance with the steering wheel angle that the driver has made, the control circuit 4 may preferably control, as appropriate, the output voltage of the boosting converter circuit 3 by receiving the steering rotation angle information from the second load.
Second Preferred Embodiment
FIG. 4 is a circuit diagram illustrating a configuration of a power supply device for a vehicle according to a second preferred embodiment of the present invention.
The second preferred embodiment differs from the first preferred embodiment in that the on/off control for the second semiconductor switching element 33 is preferably performed in the control circuit 4 . When the control circuit 4 is configured so as to detect the voltage between the ends of the inductor 31 , the control circuit 4 can perform the on/off control for the first semiconductor switching element 32 and the second semiconductor switching element 33 .
Other features are substantially the same as in the first preferred embodiment, and explanations thereof are omitted.
Third Preferred Embodiment
FIG. 5 is a circuit diagram illustrating a configuration of a power supply device for a vehicle according to a third preferred embodiment of the present invention.
The third preferred embodiment differs from the second preferred embodiment in that the connection order of the first semiconductor switching element 32 and the second semiconductor switching element 33 is reversed. With a configuration in which the control circuit 4 performs the on/off control for the first semiconductor switching element 32 and the second semiconductor switching element 33 , preferably, the first semiconductor switching element 32 may be disposed on the high-voltage side and the second semiconductor switching element 33 may be disposed on the low-voltage side, as shown in FIG. 5 .
Other features are substantially the same as in the first preferred embodiment, and explanations thereof are omitted.
Fourth Preferred Embodiment
FIG. 6 is a circuit diagram illustrating a configuration of a power supply device for a vehicle according to a fourth preferred embodiment of the present invention.
The fourth preferred embodiment differs from the second preferred embodiment in that the fourth preferred embodiment preferably includes a P-channel FET as the second semiconductor switching element 33 while the second preferred embodiment includes an N-channel FET as the second semiconductor switching element 33 . With a configuration in which the control circuit 4 performs the on/off control for the first semiconductor switching element 32 and the second semiconductor switching element 33 , the same operation can be achieved by configuring the power supply device such that a negative potential is applied to the gate terminal when a P-channel FET is used as the second semiconductor switching element 33 .
Other features are substantially the same as in the first preferred embodiment, and explanations thereof are omitted.
While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims. | A power supply device is provided for a vehicle having an idling-stop function, the power supply device including a boosting converter circuit with small loss that compensates for a voltage drop of a battery during starting of the engine and performing a protection function against a case in which the polarities of the battery are mistakenly connected in reverse. A series circuit including two MOSFETs serially connected to one another and an inductor is connected to the ends of a DC power source. A diode is connected to the connection point between the two MOSFETS serially connected to one another and the inductor, and a capacitor is connected in parallel to the two MOSFETS serially connected to one another. The two MOSFETs are serially connected such that the polarities of respective body diodes thereof are opposite to each other. | 5 |
[0001] This application claims benefit of Serial No. 178-2010, filed 1 Mar. 2010 in Chile and which application is incorporated herein by reference. To the extent appropriate, a claim of priority is made to the above disclosed application.
FIELD OF INVENTION
[0002] The present invention is relevant in biomining, particularly in bioleaching. A method to increase the production of extracellular polymeric substances (EPS) in a Acidithiobacillus ferrooxidans culture, one of the most important microorganisms in biomining, is presented. This method has been developed using a mathematical model of Acidithiobacillus ferrooxidans metabolism, which allows to predict how to enhance EPS production, that was validated experimentally, giving origin to the method of the invention. EPS is responsible for bacterial adhesion to the mineral and biofilm formation and are therefore of great importance in bioleaching.
BACKGROUND OF THE INVENTION
[0003] Biomining can be defined as the use of microorganisms in the recovery of metals from minerals. Its traditional expression is bioleaching, the solubilization of metals from the corresponding sulfide minerals in an acidic medium using the direct or indirect action of microorganisms (Rawlings D. E., MicrobCell Fact. 4(1) (2005) 13).
[0004] For example, species from the Acidithiobacillus genre are capable of oxidizing reduced sulfur compounds, such as sulfide, elemental sulfur, thionates, etc. using oxygen as an electron acceptor, which allows the solubilization of metallic ions from minerals. During this process species such as sulfite and thiosulfate are generated as intermediates and sulfuric acid is generated as a final product.
[0005] Within the variety of microorganisms that participate in these processes, one of the most studied is Acidithiobacillus ferrooxidans , an acidophilic, autotrophic and quimiolitotrophic bacteria, which means that it lives in environments with acidic pH between 1.3 and 4, it uses CO 2 as carbon source and it obtains energy from inorganic compounds. In particular, Acidithiobacillus ferrooxidans oxidizes iron (II) to iron (III) using oxygen as an electron acceptor. Iron (III) is a potent oxidizing agent, that can oxidize reduced sulfur compounds or other reduced compounds (Watling. The bioleaching of sulphide minerals with emphasis on copper sulphides—A review. Hydrometallurgy (2006) vol. 84 (1-2) pp. 81-108).
[0006] The usual practice of bioleaching processes in the mining industry consists in charging the mineral previously crushed on an impermeable carpet forming “piles”, which are later irrigated with a diluted solution of sulfuric acid. The solubilized metal in the percolated solution that elutes from the pile (known as Pregnant Leaching Solution or PLS) is then recuperated in successive stages of extraction by solvent and electrodeposition.
[0007] Since bioleaching is a microbiological process, its efficiency can be improved by inoculating the mineral with leaching microorganisms. This inoculation can take place when the mineral is charged or during the irrigation of the pile. In the vicinity of bioleaching piles it is possible to install and operate bioreactors for the production of such microorganisms (Morales P., Badilla, R. 2006. “Proceso para aumentar la velocidad de biolixiviación de minerales o concentrados de especies metálicas sulfuradas que comprende inocular continuamente solución de lixiviación que contiene microorganismos aislados de tipo Acidithiobacillus thiooxidans o en conjunto con microorganismos aislados de tipo Acidithiobacillus ferrooxidans” . Solicitud de Patente Chilena No. 2006-02911).
[0008] It has been described that extracellular polymeric substances (EPS) from Acidithiobacillus ferrooxidans , responsible for bacterial adhesion to the mineral and biofilm formation are crucial for bioleaching. It has been demonstrated that pirite bioleaching by Acidithiobacillus ferrooxidans is significantly greater in bacteria activated with EPS that in those without it (T. Gehrke et al, Appl. Environ. Microbiol. 64 (1998) p. 2743-2747). EPS seems to have 2 roles in bioleaching: (i) mediate bacterial adhesion to the sulfide mineral surface, and (ii) concentrate iron (III) ions in the mineral-microorganism interface by complexation with uronic acids or other EPS residues, allowing the oxidative attack on the sulfur to take place. (Sand W., Gehrke T., Research in Microbiology 157 (2006)49-56).
[0009] Having established the importance of EPS in bioleaching, the problem is how to increase EPS production in leaching microorganisms like Acidithiobacillus ferrooxidans . Although the identification of genes involved in EPS formation in Acidithiobacillus ferrooxidans has been accomplished (Barreto et al., Appl. Environ. Microbiol. 71 (2005) 2902-2909), methods to improve its EPS production have not yet been developed.
[0010] The present invention tackles the problem of generating microbial cultures that carry metabolic compounds or products that improve the bioleaching rate, proposing a strategy that assures biomass production together with EPS generation or accumulation, hence obtaining a biomass culture with enhanced characteristics, more efficient for bioleaching. The technical problem has been analyzed from a metabolic engineering point of view, developing a mathematical model that represents Acidithiobacillus ferrooxidans' metabolism, based on the genome annotation of Acidithiobacillus ferrooxidans strain Wenelen (Sugio T., Miura A., Parada P., Badilla R. (2005), Cepa bacteriana de Acidithiobacillus ferrooxidans denominada Wenelen, Patent number CL 44546). Simulations developed using the model made possible the determination of which metabolic pathways must be intervene in order to increase EPS specific productivity in Acidithiobacillus ferrooxidans Wenelen.
SUMMARY OF INVENTION
[0011] A mathematical model of Acidithiobacillus ferrooxidans metabolism has been developed. The objective of the model was to predict which metabolic pathways involved in EPS biosynthesis can be favored in order to increase EPS production in culture, aiming to improve bioleaching properties.
[0012] Model analysis showed that tricarboxylic acid cycle pathway (TCA) plays a key role in biomass production and is uncoupled with EPS synthesis. It should be pointed that any metabolic pathway can be described by acid compounds as well as their salt forms.
[0013] As result of a series of simulations performed using this model, it was concluded that if TCA can be blocked, it would diminish the growth rate and increase significantly the EPS in the existing biomass.
[0014] To implement such strategy, it was determined that the inhibition of any enzyme of the TCA cycle leading to alpha-ketoglutarate, without affecting oxalacetate production, according to FIG. 1 , can be used. Particularly, citrate synthase, aconitase and isocitrate dehydrogenase. For the present invention, any kind of inhibition method can be used, being the more popular, but not limited to, genetic manipulation and addition of chemical substances, which inhibit each particular enzyme.
[0015] Genetic manipulation consists in altering the genomic material in such a way that metabolic network will be modified and properties of microorganisms changes (Palsson B. O. and Edwards J., Method for the evolutionary design of biochemical reaction networks, U.S. Pat. No. 7,127,379). In the present invention, such modification will correspond with manipulate genes producing the aforementioned enzymes, in a way that they were less chemically active.
[0016] A second way to limit the activity is using some chemical substance, which binds materially to the structure of the enzyme (Hong Kim B. and Gadd G. M., Bacterial Physiology and Metabolism, chapter 12, page 460, Cambridge University Press, 2008). Table 1 shows a list, based in a literature survey, of known inhibitors for the mentioned enzymes.
[0000]
TABLE 1
List of known inhibitors for the mentioned enzymes of TCA.
Enzyme
Inhibitor
Reference
Isocitrate
aluminium
Yoshino et al. Inhibition by
dehidrogenase
aluminum ion of NAD- and NADP-
dependent isocitrate
dehydrogenases from yeast. Int J
Biochem (1992) vol. 24 (10) pp.
1615-8
oxalomalate
Dhariwal y Venkitasubramanian.
NADP-specific isocitrate
dehydrogenase of Mycobacterium
phlei ATCC 354: purification and
characterization. J Gen Microbiol
(1987) vol. 133 (9) pp. 2457-60
p-cloromercuribenzoate
Dhariwal y Venkitasubramanian.
NADP-specific isocitrate
dehydrogenase of Mycobacterium
phlei ATCC 354: purification and
characterization. J Gen Microbiol
(1987) vol. 133 (9) pp. 2457-60
DA-11004
Shin et al. Anti-diabetic effects of
DA-11004, a synthetic IDPc inhibitor
in high fat high sucrose diet-fed
C57BL/6J mice. Arch Pharm Res
(2004) vol. 27 (1) pp. 48-52
nitric oxide
Yang et al. Inactivation of NADP(+)-
dependent isocitrate dehydrogenase
by nitric oxide. Free Radic Biol Med
(2002) vol. 33 (7) pp. 927-37
citrate synthase
palmitoyl - CoA
Else et al. A new
spectrophotometric assay for citrate
synthase and its use to assess the
inhibitory effects of palmitoyl
thioesters. Biochem J (1988) vol.
251 (3) pp. 803-7
palmitoyl tioglicolato
Else et al. A new
spectrophotometric assay for citrate
synthase and its use to assess the
inhibitory effects of palmitoyl
thioesters. Biochem J (1988) vol.
251 (3) pp. 803-7
(3R,S)-3,4-Dicarboxi-3-
Bayer et al. Evidence from inhibitor
hidroxibutil-CoA
studies for conformational changes
of citrate synthase. Eur J Biochem
(1981) vol. 120 (1) pp. 155-60
FCMX
Schwartz et al. alpha-Fluoro acid
and alpha-fluoro amide analogs of
acetyl-CoA as inhibitors of citrate
synthase: effect of pKa matching on
binding affinity and hydrogen bond
length. Biochemistry (1995) vol. 34
(47) pp. 15459-66
FAMX
Schwartz et al. alpha-Fluoro acid
and alpha-fluoro amide analogs of
acetyl-CoA as inhibitors of citrate
synthase: effect of pKa matching on
binding affinity and hydrogen bond
length. Biochemistry (1995) vol. 34
(47) pp. 15459-66
D-Serine
Zanatta et al. In vitro evidence that
D-serine disturbs the citric acid cycle
through inhibition of citrate synthase
activity in rat cerebral cortex. Brain
Research (2009) vol. 1298 pp. 186-93
suramin
Salvarrey y Cazzulo. Citrate
synthase from Crithidia fasciculata :
inhibition by adenine nucleotides
and suramin. Comp Biochem
Physiol, B (1982) vol. 72 (1) pp. 165-8
ATP
Salvarrey y Cazzulo. Citrate
synthase from Crithidia fasciculata :
inhibition by adenine nucleotides
and suramin. Comp Biochem
Physiol, B (1982) vol. 72 (1) pp. 165-8
aconitase
fluoroisocitrate
Morrison y Peters. Biochemistry of
fluoroacetate poisoning: the effect of
fluorocitrate on purified
aconitase. Biochem J (1954) vol. 58
(3) pp. 473-9
alloxan
Boquist y Ericsson. Inhibition by
alloxan of mitochondrial aconitase
and other enzymes associated with
the citric acid cycle. FEBS Letters
(1984) vol. 178 (2) pp. 245-8
nitric oxide
Tórtora et al. Mitochondrial
aconitase reaction with nitric oxide,
S-nitrosoglutathione, and
peroxy nitrite: mechanisms and
relative contributions to aconitase
inactivation. Free Radic Biol Med
(2007) vol. 42 (7) pp. 1075-88
S-nitrosoglutation
Tórtora et al. Mitochondrial
aconitase reaction with nitric oxide,
S-nitrosoglutathione, and
peroxynitrite: mechanisms and
relative contributions to aconitase
inactivation. Free Radic Biol Med
(2007) vol. 42 (7) pp. 1075-88
peroxinitrite
Tórtora et al. Mitochondrial
aconitase reaction with nitric oxide,
S-nitrosoglutathione, and
peroxynitrite: mechanisms and
relative contributions to aconitase
inactivation. Free Radic Biol Med
(2007) vol. 42 (7) pp. 1075-88
[0017] In particular, a preferred implementation but not limiting of the present invention is the block of TCA cycle by selective inhibition of aconitasa enzyme (EC 4.4.1.3), which catalyzes the citrate to isocitrate conversion.
[0018] Another particular but not limiting realization of the present invention is limiting aconitase specifically by the fluoroisocitrate anion. From this point on, we will identify fluoroisocitrate o any of their salt forms as FIC.
[0019] This method allows an increase of 30% in specific productivity of A. ferroxidans Wenelen.
DESCRIPTION OF THE FIGURES
[0020] FIG. 1 : Acidithiobacillus ferrooxidans Wenelen metabolic pathways relevant to the invention. Any of the paths characterized by the step from acetyl-CoA to a-ketoglutarate are susceptible of being used according to the method of invention.
[0021] FIG. 2 : Acidithiobacillus ferrooxidans Wenelen cultures specific productivity in control and FIC conditions according to the method of invention. After the first 30 hours, a significant increase in EPS specific productivity is observed in FIC cultures. Approximately a 30% of increase is observed around the 50 hours of culture, which is coincident with its exponential growth phase.
DETAILED DESCRIPTION OF THE INVENTION
[0022] A mathematical model of Acidithiobacillus ferrooxidans Wenelen (Sugio T., Miura A., Parada P., Badilla R., 2005, Cepa bacteriana de Acidithiobacillus ferrooxidans denominada Wenelen, Patente number CL 44546) has been developed aiming to establish strategies to increase the carbon flux in EPS production metabolic pathways, in order to obtain an EPS rich culture, and therefore a more efficient one for bioleaching.
[0023] To develop this model, Acidithiobacillus ferrooxidans Wenelen metabolic network was established. A metabolic network is defined as a set of biochemical reactions that describes an organism metabolism, whether they are catalyzed by enzymes or not. The stoichiometric information contained in a metabolic network with m metabolites and n reactions can be represented by a stoichiometric matrix with rows and columns associated to metabolites and reactions respectively. This matrix is of crucial importance, as it represents the translation of biological knowledge into mathematical terms (Llaneras and Picó, J. Biosci. Bioeng. (2008) 105(1):1-11).
[0024] In order to establish Acidithiobacillus ferrooxidans Wenelen's metabolic network, its genomic sequence, containing the information of the proteins this organism is capable of synthesizing, was considered. From Acidithiobacillus ferrooxidans Wenelen's genome it is possible to infer its enzymes and reconstruct the set of reactions that it can generate.
[0025] To accurately represent Acidithiobacillus ferrooxidans Wenelen biochemistry, it was necessary to account for the synthesis of its biomass precursor metabolites. To do this, a search for available information on its carbon central metabolism and amino acid synthesis pathways was conducted (Kim and Gadd, Bacterial physiology and metabolism, 2008). Once the main metabolic paths were established, DNA and RNA nucleic acids synthesis information was included in the network, as well as the synthesis of EPS precursors (Gehrke et al., Importance of Extracellular Polymeric Substances from Thiobacillus ferrooxidans for Bioleaching, Applied and Environmental Microbiology (1998) vol. 64 (7) pp. 2743-7).
[0026] The model was constructed considering 195 metabolites—13 are extracellular metabolites and 182 intracellular—and 190 reactions. Hence, a stoichiometric matrix (S) of 195 rows (m) and 190 columns (n) was obtained. The 190 reactions considered include 53 reversible reactions; 100 reactions are exclusively related to biomass constituents production; 21 reactions participate in shared processes for EPS and biomass synthesis; 44 are associated solely to EPS synthesis and 20 reactions are involved in central metabolism and energy generation.
[0027] Having defined the matrix S, the mass balance that involves each of the metabolites can be represented in mathematical terms by a set of differential equations:
[0000]
c
t
=
S
·
v
-
μ
·
c
[0000] where c=(c 1 , c 2 , . . . , c m ) is the vector of concentration of the intracellular metabolites, S is the stoichiometric matrix, v=(v 1 , v 2 , . . . , v M ) is the flux vector, and μ is the specific cell growth rate. This mass balance dynamic equation describes the evolution in time of the concentration of each metabolite (c i ).
[0028] To simplify the analysis, it is assumed that the accumulation and/or consumption of intracellular metabolites in the volume of reaction in relation to the accumulation of products and substrates consumption is negligible (pseudo stationary state assumption), obtaining the following mass balance:
[0000] S·v= 0
[0029] For the stoichiometric matrix S there are m independent equations, one for each metabolite and given that the associated reactions are n, generally with n>m, the system is underdetermined with (n−m) freedom degrees. Therefore, equation of mass balance defines a solution space, built by each possible flux (v) solution (Llaneras and Picó, J. Biosci. Bioeng. (2008) 105(1):1-11).
[0030] This method does not provide an unique flux distribution but it delimits the set of flux distributions which can be obtained by a metabolic network, providing a feasible space within the metabolic network can adapt depending on the substrates abundances or environmental conditions such as temperature, pH, etc. Therefore, the equation contains the metabolic capacities of the object modeled, in the present case, A. ferrooxidans Wenelen.
[0031] The model was programmed to perform simulations of metabolic fluxes capable to enhance EPS production in A. ferrooxidans Wenelen.
[0032] An analysis of model elementary modes points out that Acidithiobacillus ferrooxidans Wenelen is capable to canalize energy to biomass or EPS synthesis, depending of the phenotypic state of the microorganism, this is, depending on the response to environmental stimuli, A. ferrooxidans is capable to produce both in different proportions. Form a metabolic fluxes point of view, for a given energy consumption in A. ferrooxidans Wenelen, exists an inverse relation between the carbon flux used for biomass production and the one used for EPS synthesis.
[0033] Analysis of fluxes simulation results led to the conclusion that it exists one pathway which is key for biomass production but not for EPS synthesis, the tricarboxilyc acid (TCA) cycle. According to this, predictions show that if TCA cycle is blocked, carbon fluxes should be redirected towards EPS production, decreasing the biomasss production. This allows culture an inoculum of A. ferrooxidans Wenelen EPS enriched, which is potentially more efficient in bioleaching process in contact with mineral surfaces.
[0034] As was previously stated, TCA inhibition can be made at different branches, inhibiting particular enzymes.
[0035] Aconitase (EC 4.2.1.3) is one of the enzymes involved in this cycle, which catalyze citrate conversion to isocitrate, using cis-aconitate as intermediary. This enzyme is specifically inhibited by FIC. Therefore, a culture of A. ferrooxidans containing FIC will produce less biomass but this will be enriched in EPS. This also should enhance their bioleaching activity.
[0036] Example 1 shows an application of the strategy.
[0037] The application of this method using the mathematical metabolic model of Acidithiobacillus ferroxidans , can be used to design a culture process for A. ferrooxidans enriched whit EPS and therefore with enhanced properties in bioleaching.
Example 1
[0038] To compare biomass and EPS production in a Acidithiobacillus ferrooxidans , a culture with FIC and a control one, without FIC, were conducted.
[0039] Both cultures were carried in 1 L of a 9K medium described in Table 2, with the addition of 30 g/L of ferrous sulfate, with pH set at 1.8, agitation of 250 rpm and air flux of 1 VVM.
[0040] In both cultures, the same initial biomass concentration of 1*10̂7 cell/mL was inoculated. In sample 1, 80 μM of FIC was added. Cultures were kept for 288 hours and EPS and biomass concentration was periodically measured. Afterwards, specific productivity of EPS was calculated. Results are summarized in Tables 3 and 4 and in FIG. 2 .
[0000]
TABLE 2
Liquid medium 9K
Component
Concentration, (g/L)
(NH 4 ) 2 SO 4
3.0
K 2 HPO 4
0.5
MgSO 4 •7 H 2 O
0.5
KCl
0.1
Ca(NO 3 ) 2
0.01
[0000]
TABLE 3
A. ferrooxidans strain Wenelen without additive
Time
EPS
[EPS] ajusted
[hours]
cel/ml
mg/L
pg EPS/cel
[mg/l]
Constants
0.0001
3.13E+06
21.8
6.98
21.80
K
4010157.10
24
8.44E+06
23.5
2.79
25.51
N
3.41
48
4.22E+07
59.75
1.42
56.99
objetive F
5633.82
120
1.11E+08
218
1.97
245.81
144
1.35E+08
317.5
2.35
274.73
168
1.62E+08
312.5
1.93
291.23
192
1.84E+08
255
1.39
300.86
216
1.38E+08
320
2.33
306.70
288
1.12E+08
297.5
2.67
314.44
[0000]
TABLE 4
A. ferrooxidans strain Wenelen with 80 μM of FIC
Time
EPS
[EPS] ajusted
[horas]
cel/ml
mg/L
pg EPS/cel
[mg/l]
Constants
0.0001
4.69E+06
28
5.97
28.00
K
4010157.10
24
7.81E+06
33.5
4.29
36.49
N
3.67
48
6.66E+07
74
1.11
109.28
F objetive
7072.13
120
7.69E+07
341
4.44
306.36
144
4.16E+07
350
8.42
318.74
168
3.41E+07
372.5
10.94
324.73
192
1.41E+07
348.5
24.78
327.88
216
1.38E+07
315
22.91
329.65
288
1.94E+07
305
15.74
331.83
[0041] For the appropriate calibration of the model, the control sample was used. In this sample, a batch culture of Acidithiobacillus ferrooxidans was kept for 288 hours. Considering the data from measurements taken between 24 and 192 hours of culture (exponential growth phase period) a specific growth rate of m=0.016 h −1 (R 2 =0.85) was determined.
[0042] Ferric ion in the culture medium at an initial concentration of 6 g/L was completely consumed during bacterial growth (between hours 24 and 196). Then, it is possible to estimate the biomass yield over Fe +2 (Y xs ) integrating the following equations:
[0000]
S
t
=
-
Y
xs
μ
X
X
(
t
)
=
X
0
(
μ
·
t
)
[0000] with X 0 =1.0*10 7 cel/mL.
[0043] A yield of 17.8 mol of Fe +2 per gram of biomass dry weight (DW) is then obtained.
[0044] Given that substrate flux r s can be expressed as μYxs, the estimated experimental flux is of 85.45 mM/gDWh. Yield between EPS and biomass Yxp was estimated from experimental data of 23 [g EPS]/[gDW] and the corresponding flux was of 0.35 [g EPS]/gDWh. This value is only 11% of the maximal value of [g EPS]/[gDWh]. predicted by the model. This result is consistent with published data (Gehrke et al., Importance of Extracellular Polymeric Substances from Thiobacillus ferrooxidans for Bioleaching, Applied and Environmental Microbiology (1998) vol. 64 (7) pp. 2743-7) given the oxidation and growth rate obtained.
[0045] In the first 48 hours there was no significant differences in the growth rate or EPS production between sample 1, with FIC, and the control sample, without FIC. Control sample EPS concentration was of 60 mg/L while in sample 1 this concentration was of 74 mg/L.
[0046] The model was used to calculate Fe +2 consumption rate during this first stage (0-48 hours), assuming that EPS production rate in this period had to be equal to 11% of its maximal predicted value, as it was demonstrated in the model calibration experiment, and the growth rate of 0.089 h −1 . Considering this, an iron consumption rate of 121.50 mM/gDWh is obtained for this period, which is equivalent to 82% of total iron available in the system.
[0047] During the next phase, from hours 48 to 120, biomass in sample 1 remains practically constant and EPS production shows a strong increase. On the other hand, a high growth rate in the control sample continues to be observed. In this phase, EPS concentration is always higher in sample 1 in relation to the control sample, which is highly remarkable since biomass concentration in sample 1 is considerably smaller in sample 1. At 120 hours of culture, the EPS yield, expressed in pg EPS/cell, is 2 times greater in sample 1, see Table 3.
[0048] In the third phase, between 120 and 288 hours, sample 1 biomass is lower by one magnitude order that control sample, but EPS concentration in both cases are very close. The most significative difference in yield (pg EPS/cell) is achieved in 192 hours; the amount of EPS per cell is 18 times higher in sample 1 than control, as exposed in Table 3.
[0049] It is possible to appreciate clearly that predictions obtained by the model are observed in a real culture. The use of fluoroisocitrate in an A. ferroxidans culture, allows enhanced EPS production in detriment of biomass production, obtaining an A. ferrooxidans culture enriched in EPS to be used in a bioleaching system, improving efficiency of this industrial process.
[0050] Model predictions, validated by laboratory experiments, shows that an A. ferrooxidans incubated with FIC slows it biomass production rate and EPS is increased.
[0051] Even in low concentrations, FIC addition should increase EPS production, given the partial inactivation of aconitase. Preferably, FIC should be added in a concentration of 10 and 200 μM; furthermore, between 70 and 120 μM.
[0052] Results show that invention application achieves significant increments in EPS productivity during exponential growth. Application of invention over a culture produces an increase for EPS productivity between 2 and 18 times, as seen in the present example. | A method of increasing the production of extracellular polymeric substances (EPS) in an Acidithiobacillus ferrooxidans culture is disclosed. The method includes inhibiting an enzyme, such as citrate synthase, aconitase, or isocitrate dehydrogenase, in the tricarboxylic acid (TCA) cycle leading to alpha-ketoglutarate. | 2 |
The present application claims the benefit of provisional patent application number 60/317,587 filed Sep. 6, 2001.
THE FIELD OF THE INVENTION
The field of the invention is the treatment of neuropathy. More specifically, the invention relates to the use of photo-energy treatment of neuropathy such as peripheral neuropathy, diabetic neuropathy, post-polio syndrome, small fiber neuropathy, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS), wherein the neuropathy is treated and the sensory impairment of the patient is reduced.
BACKGROUND OF THE INVENTION
Neuropathy is a general term denoting functional disturbances and/or pathological changes in the peripheral nervous system. If the involvement is in one nerve it is called mononeuropathy, in several nerves, mononeuropathy multiplex, and if diffuse and bilateral, polyneuropathy. The etiology may be known, for example, arsenical neuropathy, diabetic neuropathy, ischaemic neuropathy or traumatic neuropathy, or it may be unknown.
Diabetic peripheral neuropathy is a consequence, in part, of diabetes mediated impairment blood flow to, and resultant hypoxia of nerves. The condition results in sensory impairment. Prior to the present invention, there was no known treatment for reversing the sensory impairment of this disease manifestation, although some treatments, such as capsiacin cream, tricyclic antidepressants, and valproic acid are efficacious in diminishing pain. Other studies have demonstrated some increase in conduction velocity with use of aldose reductase inhibitors. Insulin pumps or pancreas transplantation which reduce the hyperglycemia of diabetes are sometimes effective in slowing the progress of diabetic neuropathy. With each of these approaches there have been notable problems in feasibility, logistics, and efficacy, so that additional research into preventing/treating diabetic neuropathy has become a major research focus of the Juvenile Diabetes Foundation, the American Diabetes Association, and the National Institutes of Health.
Impaired sensation in the feet becomes evident to the patient and clinician several years after the onset of diabetes and, importantly, does not spontaneously regress. In other words, diabetic peripheral neuropathy is considered to be a progressive disease. Ultimately the loss of feeling can result in one or more ulcerations of the foot or feet. If the degree of sensory impairment reaches a level of 5.07 or higher, using the Semmes Weinstein monofilament test, there is a very high likelihood of ulceration, followed by amputation. Treatments that reduce sensory impairment may minimize the risk of the onset of ulcerations that often lead to amputations. Additionally, reduced sensory impairment may improve proprioception and balance, thereby reducing the likelihood of injurious falls.
Several products expected to reduce sensory impairment due to diabetic neuropathy, including nerve growth factor and aldose reductase inhibitors, in large clinical trials, have failed to meet full expectations of clinicians or patients. Prior to the present invention, there was no effective therapy available for reducing sensory impairment associated with diabetic neuropathy.
A number of pharmaceutical approaches have been taken to treat neuropathy, using medicaments to alleviate the symptoms. U.S. Pat. No. H1,899 to, Bhat, et al. discloses a method for determining a concentration of insulin-like growth factor-I (IGF-I) that defines a therapeutically effective dose of IGF-I. The patent discloses a dose that provides a therapeutic response in the treatment of neurological disorders for which IGF-I is utilized (including peripheral neuropathy, diabetic neuropathy, post-polio syndrome, small fiber neuropathy, arterial lateral sclerosis, and multiple sclerosis). The method comprises determining whether a particular dose of IGF-I causes a 1.5 fold or greater increase in the homeostatic concentration of plasma insulin-like growth factor binding proteins-2 (IGFBP-2) in a mammal that has previously received a defined dose of IGF-I. The method of the invention can also be used to determine whether or not biological tolerance has developed to a particular dose of IGF-I.
U.S. Pat. No. 6,087,392 to Reiter discloses a compound of (4-arylsulfonylamino)-tetrahydropyran-4-carboxylic acid hydroxamides which is useful in the treatment of a condition selected from the group of diseases including peripheral neuropathy. U.S. Pat. No. 6,075,053 to Hausheer discloses a method of treating patients afflicted with peripheral neuropathy by administering to a patient an effective amount of a thiol or reducible disulfide compound according to the formula set forth in the specification. U.S. Pat. No. 5,567,724 to Kelleher, et al. discloses a method of treating peripheral neuropathy using acid or alkaline phosphatase inhibitors.
U.S. Pat. Nos. 4,927,849 and 5,066,676 respectively to Caccia, et al. discloses sulfonamido derivatives having the property of inhibiting the aldose reductase enzyme system. Specific derivatives include xanthosulfonamido and benzensulfonamido derivatives, which are useful in the treatment of the complications induced by diabetes, such as those involving the eyes. The derivatives are also useful in the treatment of peripheral neuropathy.
All of the above patents require the patient to take pharmaceuticals or drugs, which involves ongoing treatments and possible side-effects. None of the above references teach or suggest the treatment of a patient having neuropathy that does not involve the use of pharmaceuticals or drugs, as does the present invention.
U.S. Pat. No. 4,930,504 discloses an array of a substantially monochromatic radiation source such as light-emitting diodes of a plurality of wavelengths, preferably three wavelengths, to treat inflammations, wounds, burns, chronic ulcerations including diabetic ulcers, deficient circulation, pain, nerve degeneration, eczema, shingles, infection, scars, acne bone fractures, muscle and ligament injuries, arthritis, osteo-arthritis, rheumatoidal arthritis, skin grafts, gingival irritation, oral ulcers, dental pain and swelling, cellulitis, stretch marks, skin tone, alopecia areata, trigeminal neuralgia, herpes, zosten, sciatica, cervical erosions and other conditions. However, this patent does not disclose that a photo-energy source may be capable of reducing sensory impairment associated with neuropathy.
The use of monochromatic infrared energy has been successfully used to treat recalcitrant dermal lesions, including venous ulcer, diabetic ulcers, and a wound related to scleroderma. (Horwitz, L. R., Advances in Wound Care, January/February, 1999). U.S. Pat. No. 5,358,503 discloses a device for the treatment of skin and subcutaneous structures with photo-energy and * therapeutic heat. The device includes a flexible pad which holds diodes in juxtaposed position with each other. Neither the Horwitz article nor U.S. Pat. No. 5,358,503, disclose the use of an apparatus for the reduction of sensory impairment associated with neuropathy.
None of the above references disclose the present invention involving the use of an apparatus for photo-energy treatment for reducing sensory impairment due to neuropathy.
SUMMARY OF THE INVENTION
The present invention is a method for the reduction of sensory impairment due to peripheral neuropathy comprising placing an apparatus which provides photo-energy in proximity to the skin and/or subcutaneous structures suffering from sensory impairment, arid irradiating the skin and/or subcutaneous structures with the apparatus with sufficient duration. (total weeks of treatments), intensity (energy in Joules per treatment) and frequency (treatments per week) to reduce sensory impairment. The reduction in sensory impairment can be measured by the Semmes Weinstein test and/or other diagnostic-type test of sensory impairment. Optionally, the apparatus may also deliver therapeutic heat so that the treatment area of the skin and the adjacent subcutaneous structure of the patient receive photo energy treatment and thermal treatment simultaneously or selectively.
DETAILED DESCRIPTION OF THE INVENTION
A variety of apparatuses can be used to generate the photo-energy needed for treatments that reduce sensory impairment. The preferred apparatus for photo-energy treatment is a plurality of diodes, defining a treatment area, each diode having a longitudinal axis and being capable of projecting a non-coherent cone of photo-energy when energized. The cone of photo-energy from each diode overlaps the cone of photo-energy from each other diode, so that the photo-energy completely covers the treatment area. The apparatus has a means for holding each of said diodes in position with each other and in proximity of the skin in substantially perpendicular relationship to said longitudinal axis.
Such means include a flexible resin-based pad, such as a polyacrylate pad, an interconnecting flexible mesh pad, a woven cloth-like material pad, a deformable matrix, such as modeling clay which can conform to an extremity, a castable material which hardens to a desired shape, or a flexible elongated strip of cloth or resin-based material that can be wrapped around a digit or directed to a small, narrow area.
The apparatus has means connected to the diodes for activating them. Such means includes switches, such as manually activated switches, and electronic switches, such as solenoids, which can be activated manually, or electronically, such as by a microprocessor. The present invention includes using an apparatus, wherein the apparatus is attached to a microprocessor which is programmed to activate and deactivate the apparatus.
Optionally, the apparatus may also deliver therapeutic heat so that the treatment area of the skin and the adjacent subcutaneous structure of the patient receive photo-energy treatment and thermal treatment simultaneously or selectively. The means for heating includes the diodes themselves, wherein the heating provided is increased with the current provided. Further heating can be provided by resistance heating, such as by resistors or heating elements. The preferred apparatus for photo-thermal treatment is described in detail in U.S. Pat. No. 5,358,503, which is hereby incorporated by reference.
Sensory impairment can be measured by a variety clinical diagnostic of tests. The most common test is the Semmes Weinstein test, where pressure is applied against the skin of affected areas using monofilaments of varying thicknesses to determine the level of sensory impairment. Other methods of determining sensory impairment include the hot-versus-cold test which is used to test sensory impairment to temperature change. The vibratory test is used to test sensory impairment to a vibrating tuning fork. The nerve conduction velocity test (NCV) measures sensory impairment by evaluating the conductivity of nerves, as does the needle electromylagram test (EMG). The quantitative sensory test gives a two point discrimination test of sensory impairment. The Romberg test is used to determine gross sensory impairment of the lower extremities as it affects balance, and the Balance Master is a device that measures gross sensory impairment of the lower extremities affecting balance in more objective terms. Other quantitative tests of sensory impairment due to neuropathy may be employed or developed in the future. Any one of these tests, alone or in combination could indicate sensory impairment resulting from neuropathy. A preferred diagnostic test is the Semmes Weinstein monofilament test.
The present method involves a sequential treatment, wherein a patient is treated at a frequency of from about one to fourteen times each week for a period of about from about five to sixty minutes a treatment. Transitory response may be observed after one treatment and longer lasting response may require additional treatments, which, in neuropathy due to a chronic condition, may be required for a period coextensive with the remainder of the patient's life. A preferred frequency is from about one to fourteen treatments weekly with a duration of from ten to fifty minutes. The total number of treatments can range from about one to 150. The patient is treated for a duration of from about one to twelve weeks. A preferred range of duration is from about two to ten weeks. The frequency and duration of treatment, as well as the total number of treatments, depends, in part, on the severity and duration of the neurological impairment as Well as the chronicity of the underlying causation of neuropathy.
The intensity of the treatment can be changed by varying the Joules of photo-energy delivered to the treatment site. Typically, from about 1450 to about 6500 Joules are delivered per affected extremity per treatment, however, fewer Joules per treatment delivered more frequently, i.e., a lower intensity with a higher frequency, may be equally effective.
The intensity of the photo-energy delivered in a treatment is calculated as the Joules per treatment. It is calculated as the product of the energy (Joules) per area (cm 2 ) per minute emitted by the photo-energy device, the treatment area (cm 2 ), and the length (minutes) of treatment. Variance in the energy emitted by the photo-energy device, the treatment area (cm 2 ), and the length of treatment (minutes) will accordingly change the intensity of the photo-energy delivered as measured in Joules per treatment. The preferred photo-energy device delivers about 1.15 Joules per cm 2 per minute (J/cm 2 /min) over the defined treatment area of about 22.5 cm 2 . As many as eight photo-energy devices may be used simultaneously to provide a treatment area of up to 180 cm 2 . Thus, a treatment using from one to eight photo-energy devices will yield a range of from about 26 to about 207 Joules per minute of treatment. Using a treatment time of about 30 minutes, the intensity of treatment would be from about 780 to about 6240 J/treatment. The intensity of the treatment of the present invention is in the range of from about 500 to about 7000 J/treatment. A preferred range is from about 500 to about 5000 J/treatment. A most preferred range is from about 1500 to about 5000 J/treatment.
The present invention further embodies the use of the above method in a prophylactic manner, so as to prevent a neurological deficit in patients afflicted with progressive chronic conditions, such as diabetes, from which neuropathy is known to eventually occur. In such circumstances, the treatment of chronic conditions will have a duration that spans the life of the patient. Alternatively, the treatment maybe subsequent to an initial series of treatments, and long-term to prevent the re-occurrence of sensory impairment, with the duration ranging up to the life-span of the patient.
EXAMPLES OF THE INVENTION
The following examples of the invention are made to illustrate the invention and are not to limit in any manner the scope of the invention, as embodied in the claims. Generally, the results of clinical tests are evaluated statistically to determine significance using what is known as a P value. For example, a P value of 0.05 indicates that there is a 5% probability that the determined relationship between the variables (i.e., between the treatment and the observed affects) in the study are by pure chance. A P value of less than 0.05 is deemed clinically significant, and the lower the P value, the greater the statistical validity.
Study 1
Methods and Materials
Forty-nine patients were treated at The Medical Center of Aurora, a HealthOne facility, Aurora, Co. in the Physical Therapy Department. The patients ranged in age from 35 to 80 years old; 25 were Type I diabetic patients and 24 were Type II diabetic patients. All had neuropathy based on the Semmes Weinstein (SW) monofilament test which measures the ability of the patient to feel a monofilament applied to their skin. In addition, the ability to detect hot-versus-cold (H/C) was also absent or impaired in each patient. No treatments or pharmaceuticals that would have modified circulation in the lower extremities were employed during the 30 days prior to beginning this study. No changes were made in the standard of medical care associated with diabetes for these subjects, including insulin or oral hypoglycemic agents, diet, blood pressure medications, and exercise. Forty-nine (49) diabetic subjects whose SW, H/C, and gait analysis (the patient's ability to walk normally) values were abnormal were treated.
Procedure
Photo-energy was delivered from a series of 60 gallium aluminum arsenide diodes in a flexible pad (diode array) placed on the patient's feet and/or lower leg. Four diode pads (60 diodes in each pad) were used during the treatment of each lower extremity. Each treatment was for 30 minutes. The intensity of the treatments was about 3100 J/treatment of the lower, extremity, which was delivered over a treatment area of about 90 cm 2 . One diode pad was placed on the distal posterior aspect of the patient's tibia, and another diode array was placed over the patient's anterior distal tibia. One pad was placed on the dorsal and another on the ventral surface of the patient's foot. This was done to each foot. An alternate pad placement was used specifically at the plantar aspect of each foot if the posterior tibia region was uncomfortable for some subjects. Each subject received a total of 12 treatments having a duration of 30 minutes that were administered three times a week for one month.
Several sizes of Semmes Weinstein monofilaments (3.22, 3.84, 4.08, 4.17, 4.31, 4.56, 4.74, 4.93, 5.07, 5.18, 5.46, 5.88, 6.10, and 6.45) were applied to at least three areas of the plantar side of the feet. As far as possible, the same locations were tested at each visit. The filament was applied until it began to bend, and was held in place for approximately 1.5 seconds. Each site was tested three times. Care was taken to test areas that had the least thickness of the keratin layer. The test sites were the great toe, plantar arch region, and the fourth toe. The response to the filament testing was based on the subjective response from the patient of “NOW” when the patient could feel the filament. Hot/cold testing was also done at the same test sites. Response to the hot/cold testing was determined from subjective reports of whether the patient could sense the hot or cold bar. These were graded as absent, impaired, or intact.
The data for Type I and Type II diabetic patients were grouped and analyzed by repeated measured analysis; values reported are means±standard deviation (SD). The statistical significance, expressed as the P value, was P<0.001.
Results
The ages of subjects, Type of diabetes (I or II), SW values, and hot/cold (H/C) detection ability prior to beginning the study and after photo energy treatment are shown in Tables 1 and 2. Type I diabetic patients (60.4±12.8 years old) were approximately 12 years younger than the Type II diabetic subjects (72.5±5.5 years old).
Baseline SW deficits were virtually identical in the Type I (mean±SD: 5.49±0.52) and Type II (mean±SD: 5.44±0.47) (Table 1). Thirteen Type I diabetic subjects and 13 Type II diabetic subjects had absent sensation to H/C prior to treatment.
Reduction in sensory impairment was noted after six treatments and further improvement was noted over six additional treatments. After 12 [photo-energy treatments, 100% of the Type I subjects had Semmes Weinstein monofilament values below 5.07. Mean Semmes Weinstein values for all 25 Type I subjects were 4.26±0.34 after twelve treatments. A similar response to photo-energy treatment in Type II diabetic subjects was observed. Specifically, after 12 treatments with photo-energy, 100% of the Type II subjects had Semmes Weinstein values below 5.07, and the mean for all 24 subjects was 4.45±0.32. The mean (±SD) SW values before and after 12 treatments with photo-energy for all diabetic subjects are shown in Table 1.
Before treatment, none of the subjects (Type I or Type II) had intact ability to discriminate hot from cold (Table 2). After 12 treatments with the photo-energy device, all the subjects converted from absent and impaired H/C sensation to impaired and intact ability to discriminate hot from cold (Table 2).
TABLE 1
Subject characteristics,
Semmes Weinstein (SW) monofilament.
SW Monofilament Values
Diabetes
Type
N
Age
Baseline
6 Treatments
12 Treatments
Type I
25
60 ± 12
5.49 ± 0.52
4.74 ± 0.38
4.26 ± 0.34*
Type II
24
72 ± 5
5.44 ± 0.47
4.84 ± 0.36
4.45 ± 0.32*
TABLE 2
Subject characteristics,
hot/cold sensation deficits.
Hot/Cold
Baseline
After 12 Treatments
Diabetes
Absent
Impaired
Intact
Absent
Impaired
Intact
Type I
13
12
0
0
16
9
Type II
13
11
0
0
30
4
N = number of subjects
Values are Mean ± Standard Deviation
Baseline = patient characteristics before treatment with MIRE
SW = Semmes Weinstein monofilament
*P < 0.0001 vs. control
The examples demonstrate that photo-energy treatments using the photo energy device with the desired frequency, duration and intensity reduced sensory impairment in diabetic patients, as measured by the Semmes Weinstein test and the hot/cold sensation test.
Study 2
Eight patients exhibiting sensory impairment due to neuropathy as the inability to sense the Semmes Weinstein 5.07 monofilament at three tested sites on both feet received treatments with [photo energy]—photo-energy—to determine whether sensory impairment was reduced after treatment. Each patient served as their own control, receiving treatment on only one foot initially. The patients received 12 treatments for 30 minutes to an area of about 45 cm 2 delivering a photo-energy intensity of approximately 1550J/treatment over a period of about one month. At the conclusion of treatment of the first foot (Part I of the study), the second foot was treated with the same protocol (Part II of the, study). Fifteen lower extremities were evaluated since one patient withdrew from the study after successfully completing treatment on the first foot.
Results
Part I
At the conclusion of the treatments, all of the actively treated feet (n=8) obtained a reduction in sensory impairment as measured at one or more pre-tested sites by the Semmes Weinstein. 5.07 monofilament test. At that point, one patient purchased the photo energy device, and withdrew from the study. None of the control feet (n=8) obtained any reduction in sensory impairment as measured at three pre-tested sites by the Semmes Weinstein 5.07 monofilament test.
Part II
At the conclusion of treatments of the second (control) feet (n=7), all of the feet obtained a reduction in sensory impairment as measured at one or more pre-tested sites as measured by the Semmes Weinstein 5.07 monofilament test.
Each foot was found to have a reduction of sensory impairment after treatment according to the claimed method.
Study 3
Ten patients exhibiting sensory impairment due to neuropathy as tested by the inability to sense the Semmes Weinstein 5.07 monofilament test at three sites on both feet received treatments with photo-energy. The patients received ten treatments over a one month period on an area of about 45 cm 2 with an intensity of about 1550 J/treatment. Nine patients Were treated on both feet, and one patient Was treated on one foot. One other patient received only nine treatments.
Results
The patient treated on one foot experienced a reduction of sensory impairment, purchased the photo-energy device and dropped out of the study. Of the remaining nine patients, all of the actively treated feet (n=19) obtained a reduction of sensory impairment as measured at one or more of the pre-tested sites by the Semmes Weinstein 5.07 monofilament test.
Study 4
Eight patients exhibiting sensory impairment due to neuropathy, as tested by the Semmes Weinstein 5.07 monofilament test at from, three to five sites on both feet received treatment with photo-energy on one foot, and a placebo treatment of the second foot. The test was double-blind, in that neither the patient nor the evaluator knew which was the placebo. The patients received one treatment for 45 minutes over a treatment area of about 90 cm 2 , with a photo-energy intensity of about 6500 J/treatment.
Results
All of the actively treated feet (n=8) obtained reduction in sensory impairment as measured by the Semmes Weinstein monofilament test at all the pre-tested sites. Of the placebo treated feet (n=8), six of the eight experienced no reduction in sensory impairment, and two obtained some reduction in sensory impairment at several of the pre-tested sites.
Additional studies have been made, further supporting the results of this study. A follow-up evaluation of the treated patients indicated that the reduced sensory impairment Was less evident with time. This data indicates a long-term therapy involving photo-energy may be necessary to maintain reduced sensory impairment at the desired levels. | A method for the reduction of sensory impairment due to peripheral neuropathy comprising placing an apparatus which provides photo-energy in proximity to the skin and/or subcutaneous structures suffering from sensory impairment, and irradiating the skin and/or subcutaneous structures with the apparatus with sufficient duration (total weeks of treatments), intensity (energy in Joules per treatment) and frequency (treatments per week) to reduce sensory) impairment. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present patent application is a continuation application of International Patent Application No. PCT/EP2009/006819, filed Sep. 22, 2009, which is based on, and claims priority to, German Patent Application No. 10 2008 049 877.7, filed Sep. 30, 2008, both of which are incorporated herein in their entireties by reference.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The invention relates to a method for evaluating fluorescence measurement data in at least one-dimensional spatial resolution from a sample and a control unit for a laser scanning microscope.
(2) Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Fluorescence correlation spectroscopy (FCS) can be used to examine variable substance concentrations in the microscopic range caused by diffusion and other transport processes in a sample. Physical and biological transport processes in or through a single volume having a diameter of about 200 nm can be observed in this way. Spatial resolution of microscopic transport processes is achieved by scanning fluorescence correlation spectrography (S-FCS), also referred to as image correlation spectroscopy (ICS). Time spans of seconds to minutes can be tracked.
Raster image correlation spectroscopy (RICS) allows tracking within a cell or between cells separated by a membrane in the microsecond and millisecond range in two or three-dimensional spatial resolution (Digman et al.: “Measuring Fast Dynamics in Solutions and Cells with a Laser Scanning Microscope” in “Biophysical Journal”, Vol. 89, August 2005, pp. 1317-1327). The sample is optically scanned here in a two or three-dimensional grid. In the typical process, time series are recorded. It is advantageous to use a laser scanning microscope (LSM) for scanning correlation spectroscopy. During the optical scanning movement of a RICS measurement, digital sampling values are electronically recorded at a typically constant sampling frequency and further processed into pixel values. Each pixel value is determined from one or multiple sampling values. Scanning along the first scan direction is repeated along a second scan direction after the scanning beam has been shifted (scan gap) such that a series of pixel rows is recorded.
To be able to make statements about transport processes in a sample, correlation-spectroscopic measuring procedures are typically evaluated by determining correlations of the fluorescence measurement data such as auto or cross-correlations and by adapting mathematical transport models to these correlations, for example, by means of curve fittings. The adjusted models can be used to determine sample properties such as diffusion constants. The transport models are available in the form of mathematical functions, and the parameters of these functions are adjusted. Such correlation analyses with respect to RICS measurements are performed separately for several, typically overlapping, regions of the scan field. The determination of model parameters in each region, i.e. the determination of the spatial distribution of the model parameters within the sample, is called mapping. The results of correlation analyses can be presented graphically, e.g. using false colors.
It is a problem that areas can be contained in one or several sample regions that contain little or no information and therefore falsify the results of the analysis. For example, these can be dark, almost fluorescence-free areas in which noise is detected at best. It is possible in areas of low fluorescence that a correlation of measurement data of the corresponding sample region cannot be evaluated for lack of statistics. If sample properties such as a diffusion constant are determined in such sample regions despite their low information content, adapting the parameters of a model function by curve fitting will result in absurd values for the desired sample properties despite good adjustment quality. Values could be obtained for a diffusion constant that is too high by several orders of magnitude.
It is known from prior art that faulty fluorescence correlation analyses can be filtered out by comparing the adapted model function parameters, that is, the results of the curve fittings, to meaningful ranges of values. If the results are outside these ranges of values, they are discarded and not used for determining the desired sample properties. In addition to restricting the values to ranges, it is known to discard the results of curve fittings if the mean value deviations of the model function parameters exceed a preset threshold or if the ratio of the standard deviations of the model function parameters to their best values exceeds a predetermined threshold. All approaches listed above have the disadvantage that the meaningful ranges of values or the threshold values, respectively, have to be determined as so-called a priori knowledge in time-consuming test series. The rigid limitation to a specific range of values or thresholds diminishes the accuracy of the evaluation since statistically correct correlations that result in model parameter values outside the limits will be discarded. In addition, one or, if several sample regions are mapped, multiple elaborate and time-consuming curve fittings have to be performed before the results can be checked for meaningfulness.
The problem to be addressed by the invention therefore is that of providing a method and control unit of the types mentioned above with the help of which sample properties can be determined from fluorescence correlations in a simpler, faster and more accurate way.
BRIEF SUMMARY OF THE INVENTION
According to the invention, a degree of suitability for one or several regions of the sample for correlation analysis is determined. A quantity is considered a degree of suitability in accordance with the invention if it gives a quantitative description of the information content of the corresponding region or of the error to be expected in a correlation evaluation and can therefore be used as a criterion for filtering and/or selecting the corresponding region for a correlation analysis. In particular, it can be a scalar value, a multi-component vector, or a higher-order tensor. In other words, a characteristic value is determined for the corresponding region that quantifies its suitability for a correlation analysis. According to the invention, a quantitative check of data consisting of discrete points for similarity that takes translations among the data points into account is considered a correlation evaluation or correlation analysis.
The invention allows more refined filtering without requiring an elaborate and time-consuming curve fitting. Finer filtering allows higher accuracy when determining the sample properties. A decision whether to perform a curve fitting at all can then be made based on the degree of suitability determined. Some out of several regions can be selected for a curve fitting while others can be discarded in this way. Alternatively, curve fittings can be performed unconditionally for all regions and the corresponding degree of suitability for the correlation analysis can be stored as a quality characteristic in addition to the adapted model function parameters. In this way, the results can later be filtered by degree of suitability without having to perform another curve fitting. At any rate, filtering advantageously is not tied to the value associated with one or several specific model parameters. In particular, it will be possible to distinguish sample regions that are relevant for evaluation from non-relevant sample regions even before the elaborate curve fitting by advantageously determining the degree of suitability before performing a curve fitting for adapting a model function to the correlation. This cannot be done with the known methods, especially not in sample regions that only contain noise.
Advantageously, the degree of suitability is determined by determining one at least one-dimensional correlation with multiple correlation data points based on measurement data from the corresponding region and counting correlation points that show a statistically significant deviation from a comparative set within the correlation.
The invention can be applied both to spatial and temporal correlations. The number determined in this way is advantageously output or stored but it can also be processed immediately, such as in a decision on performing a curve fitting.
According to the invention, the number of significantly deviating correlation points in the corresponding correlation is used as the degree of suitability of that region. It represents a highly accurate statement about the information content of the corresponding sample region with respect to a correlation analysis, such as by means of a curve fitting.
Preferably, only a discontinuous or continuous series of neighboring correlation points that begin at the maximum of the correlation is counted. The most informative data points for a correlation analysis are in the area around the maximum of the correlation. The method is simplified and accelerated with almost unchanged accuracy by limiting the count to a linear region beginning at the maximum. While the maximum is at the origin of the coordinates in an autocorrelation, it can be at a distance from the coordinate origin in a cross-correlation so that the correlation maximum has to be determined before the count.
In a preferred embodiment, a proper subset of the correlation (i.e. its data points), especially a proper subset of a quadrant of the correlation, is used as the comparative set. The proper subset can be rectangular and, in particular, a square shape. This also helps to simplify and accelerate the method with almost unchanged accuracy. The corner point of the quadrant may also be the maximum of the correlation instead of the coordinate origin. Limitation to a maximum of one quadrant utilizes the fact that the information that is essential for detecting a shift is particularly contained in the fourth quadrant (relative to the correlation maximum).
It is advantageous for determining the significantly deviating correlation data points to determine a value of a statistical quantity within the comparative set and to find those correlation data points significantly deviating which have a value that exceeds a threshold that can be, or is, preset relative to the value of the statistical quantity. The informative data points can be found easily and quickly in this way.
Advantageously, a mean value of the comparative set is used as the statistical quantity and a multiple of a standard deviation of the mean value is used as the threshold value. These quantities can be determined with little computational effort and allow a highly precise statement about the information content of the data points.
In another embodiment of the invention, the degree of suitability is determined by determining an at least one-dimensional correlation with multiple correlation data points based on measurement data from the corresponding region, then calculating a ratio of positive to negative correlation values. The ratio of positive to negative correlation values is shifted in favor of the positive values in meaningful correlations with respect to a correlation analysis. Therefore the ratio of positive and negative values determines suitability for a correlation analysis. The ratio determined is advantageously output or stored but it can also be processed immediately, such as in a decision on performing a curve fitting. In addition to finding the statistically significant data points described above, the determined ratio can also be used for obtaining the degree of suitability of the region.
The ratio of positive and negative values is preferably obtained as the quotient of either the positive maximum value of the correlation and the negative minimum value of the correlation, or of the number of positive correlation values and the number of negative correlation values. These quotients can be calculated with little computational effort.
In a first embodiment, the corresponding degrees of suitability are determined for multiple regions, one of the regions is selected for a curve fitting based on the degrees of suitability, and the corresponding curve fitting is performed. This prevents unnecessary curve fittings that would only affect the result adversely.
In an alternative second embodiment, curve fittings are performed for multiple regions, and the corresponding degree of suitability is stored with the results of these curve fittings. This allows later filtering of the results of the curve fittings and determining the accuracy of the model parameters. It is advantageous to first record the correlation spectroscopy measurement data using a laser scanning microscope.
The invention also comprises a computer program that is set up for performing the method of the invention, and a control unit for a laser scanning microscope that is software-complemented for performing a method according to the invention, as well as a respectively equipped laser scanning microscope.
In particular, the invention includes a control unit for a laser scanning microscope, and said control unit determines a degree of suitability for a correlation analysis for evaluating fluorescence measurement data of a sample in at least one-dimensional spatial resolution.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The invention will be explained in more detail below with reference to embodiments. The figures show the following:
FIG. 1 shows a block diagram of a laser scanning microscope;
FIG. 2 shows a confocal fluorescence recording of the edge region of a cell;
FIG. 3 shows a flow chart of an evaluation method according to the invention;
FIGS. 4A and 4B show a correlation of a slow diffusion process;
FIGS. 5A and 5B show a correlation of a fast diffusion process;
FIGS. 6A and 6B show an adapted two-dimensional model function with residual errors; and
FIGS. 7A-7C show resulting diffusion mappings without filtering, with prior art filtering, and with filtering according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
In describing preferred embodiments of the present invention illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.
FIG. 1 is a diagrammatic view of an LSM (Laser Scanning Microscope) that is controlled using a control unit 34 . The LSM is of modular design and consists of a lighting module L with lasers 23 , a scanning module S, a detection module D, and the microscope unit M with a microscopic lens 21 . The control unit 34 can influence the light from the lasers 23 through barn doors (literally, “light valves” or “light flaps”) 24 and attenuators 25 before it is fed via optical fibers and coupling optics 20 into the scan unit S and concentrated there. The light passes via the main beam splitter 33 and the X-Y scanning unit 30 comprising two galvanometer mirrors through the microscopic lens 21 towards the sample 22 where it lights a focus volume (not shown).
Light reflected from the sample or emitted fluorescent light is conducted through the microscopic lens 21 via the scanning unit S and through the main beam splitter 30 into the detection module D. The main beam splitter 30 may for example be designed as a dichroic color splitter for fluorescence detection. The detection module D comprises multiple detection channels that are separated by color splitters 29 , each of said channels with a pinhole diaphragm 31 , a filter 28 , and a photomultiplier 32 . Slotted diaphragms (not shown) may be used instead of pinhole diaphragms 31 , e.g. when there is line lighting. The confocal pinhole or slotted diaphragms 31 are used to discriminate sample light that does not originate from the focus volume. The photomultipliers 32 therefore only detect light from the focus volume. The scanning unit 30 can be used to move the confocally lit and recorded focus volume of the sample 22 over the sample 22 to record a pixel-by-pixel image by turning the galvanometer mirrors of the scanning unit 30 in a defined way. The control unit 34 directly controls both the movement of the galvanometer mirrors and the switching of the lighting using the barn doors 24 or attenuators 25 . The data from the photomultipliers 32 is also recorded via the periphery interface.
FIG. 2 shows a fluorescence recording in the edge region of a biological cell as sample 22 with an exemplary image size of 512×512 pixels for which the photomultipliers 32 were operated in photon count mode. The image was rasterized in black and white for better visibility. The cell edge stretches in an approximate diagonal from the top left to the bottom right part of the image. It is obvious that the bottom left portion of the image does not contain information and that the fluorescence activity in the top right portion of the image is distributed unevenly. For an example of a diffusion mapping, the image is divided into multiple regions B mn of the same size, for example 128×128 pixels, and a diffusion constant is to be determined by correlation analysis for each of these regions. These regions may overlap. At an overlap of one half in horizontal and vertical direction, there will be 49 sample regions (m=0 . . . 6; n=0 . . . 6) to be evaluated.
FIG. 3 shows an exemplary embodiment of the method according to the invention in the form of a flow chart. For each sample region B mn , a separate two-dimensional correlation G mn such as the autocorrelation of the corresponding region is calculated from the intensity values of the pixels. Each correlation consists of a two-dimensional set of i=0 . . . (r×s), e.g. 0 . . . 128×128 data points (x i ,y i ) having a value G mn (x i ,y i ) that can be graphically represented along a third coordinate or by color coding. Alternatively, one-, three-, or multidimensional correlations with a corresponding set of data points can be used.
FIGS. 4A and 4B and FIGS. 5A and 5B show two examples of correlations G(x i ,y i ) in pseudo-3D representation. The partial figures each show different viewing angles. The coordinate origin of correlation G is in the maximum of the correlation. The correlation shown in FIGS. 4A and 4B represents a slow diffusion process, which is apparent from the flat incline both in x and in y direction. The correlation shown in FIGS. 5A and 5B however represents a fast diffusion process since it drops sharply in y direction.
According to the method depicted in FIG. 3 , an informative data point analysis is then performed for each region B mn of the mapping to determine a degree of suitability of the corresponding region B mn . The informative data point analysis initially consists in the selection of a statistically representative comparative set V from the correlation data points G mn (x i ,y i ). For example, a region of 80×80 data points (x i ,y i ) is selected as comparative set V. For illustration, FIGS. 4A and 4B show a square comparative set V as delineated by a broken line. This is a proper subset of the fourth quadrant of the correlation G. Alternatively, the full quadrant or an even larger region could be used as the comparative set. It is advantageous to limit the size of the comparative set, e.g. to 80×80 data points. If in principle a full quadrant is used and the correlation size is 128×128 data points, the comparative set V would be 64×64. However only an 80×80 comparative set is used for a correlation size of 256×256 due to the limit. FIGS. 5A and 5B indicate an alternative form of a comparative V in the same way as in FIGS. 4A and 4B . It is a continuous series of neighboring correlation data points that begins in the coordinate origin at the maximum of correlation G. Alternatively, individual points from such a series can be used as comparative set.
As an alternative to a single rectangular region, the comparative set can be composed of multiple disjunctive sections of correlation data of regular or irregular shape that are selected at random or based on a predefined pattern. For example, a regular chessboard pattern or a random distribution of single points (x i ,y i ) could be used in the two-dimensional case, and an interrupted cubic pattern in the three-dimensional approach. The comparative set can be selected automatically or based on a predefined pattern. Alternatively, the user can determine the type, shape, orientation and size of the comparative set.
After the comparative set has been selected automatically, two statistical parameters of the comparative set are determined in a first step for determining the degree, namely the arithmetic mean and the standard deviation of the comparative set. In an additional step, the value range of the correlation data points can optionally be examined for a ratio of positive data points G mn (x i ,y i )>0 to negative data points G mn (x i ,y i )<0 in a predefined window of the correlation G mn , which can be used as an indication for determining the degree. The window checked for the value range can for example be located along the x axis of the correlation G mn . The ratio can be determined mathematically as the difference or quotient of the number of positive and the number of negative data points. The minimum and maximum values of the correlation can be compared in lieu of their number. For example, if the numbers coincide or the minimum and maximum values are of the same magnitude, the degree of suitability is arbitrarily set to zero. A degree of suitability that was determined based on the statistical parameters only can later be scaled based on the resulting ratio. Alternatively, only the determined ratio can be used as degree of suitability, e.g. by appropriate scaling to a comparable number of pixels.
In general, the number of those data points (x i ,y i ) for which the value G mn (x i ,y i ) significantly deviates from the comparative set can be used as a degree of suitability of the examined region B mn . These data points (x i ,y i ) can be determined using the statistical parameters of the comparative set, for example by comparing the correlation value G mn (x i ,y i ) to the mean value of the comparative set. It is checked, for example, if the correlation value G mn (x i ,y i ) is more than twice the standard deviation above the mean value. If this condition applies, the corresponding data point (x i , y i ) is considered to be informative for a correlation analysis because it significantly deviates from the comparative set. The number of informative data points (x i ,y i ) in the correlation G mn that were determined successively in this way will be utilized as degree of suitability at the end of the informative data analysis. The degree of suitability is compared to a threshold value that the user can preset. For example, a curve fitting will be performed and its result stored only if the degree of suitability is greater than the threshold value. If the degree of suitability is lower, the user is explicitly asked in the example shown if a curve fitting should be performed anyway. In other embodiments the user is not asked in this case but region B mn is automatically marked non-informative, and the method continues with the next region.
It was found, according to the invention that determining informative data points can also advantageously be limited to a predefined window in the correlation G mn , e.g. to data points along the x-axis of the correlation G mn , such as a maximum of 30 directly adjacent data points, wherein the examination and count is started next to the origin at data point G mn (1,0). Such a window can help to determine the degree of suitability quickly and at sufficiently high accuracy since a correlation curve should drop over a range of ten to thirty data points to obtain a good evaluation using an adjustment calculation. Advantageously, the data point at the origin, G mn (0,0), is generally left out because it does not have informative value. If the correlation drops immediately after the origin value G mn (0,0), this indicates that only noise was recorded in the corresponding sample region B mn . It is preferred that an uninterrupted series of adjacent correlation points along the x-axis is examined, but patterns with a specific (e.g. non-linear) function can be used for selecting data points to be examined. The comparative set should at any rate be statistically relevant and make up a substantial portion of the corresponding correlation G mn .
The informative data point analysis and, optionally, the correlation analysis may be performed regardless of the resulting degrees for all regions B mn and stored together with the corresponding degree of suitability for later filtering. In an alternative embodiment, the correlation analysis may be performed regardless of the resulting degrees for all regions B mn and stored together with the corresponding degree of suitability for later filtering.
In addition or as an alternative to mean value and standard deviation, other statistical parameters can be derived from the comparative set and used in the conditions for the values of the individual correlation data points in order to determine data points (x i ,y i ) that deviate statistically significantly from the comparative set.
FIGS. 6A and 6B show an adapted two-dimensional model function G mn (x i ,y i ) (partial FIG. 6A ) in pseudo-3D with residual errors R mn (x i ,y i ) (partial FIG. 6B ). The model function shown is merely an example.
FIGS. 7A-7C show examples of diffusion mappings that were determined from the fluorescence image of FIG. 2 using different evaluation methods. The mappings in the left column are color-coded, and the right column shows a corresponding black-and-white grid. Partial FIG. 7A shows an unfiltered mapping. It is apparent that extremely high diffusion coefficients are assigned to some regions outside the cells due to the forced curve fitting while no meaningful diffusion coefficients can be detected in vast parts of the cell due to the necessary scaling of the false colors. Partial FIG. 7B shows a mapping that was subsequently filtered for the model parameter values. The known filtering based on model parameters for example removes the regions shown black in the interior of the cell although these regions have a normal drop in correlation. While this can be improved by setting specific filtering limits, it is very time-consuming to determine these. Partial FIG. 7C finally shows the result of a filtering based on degrees of suitability determined according to the invention, for example the number of informative correlation data points in the corresponding region B mn . The degrees of suitability allow highly accurate filtering that omits no regions B mn inside the cell and still correctly determines the transition to the non-informative regions B mn .
Advantageously, the user can predefine the size and overlap or the number of regions B mn to be mapped as well as the specific sample model and individual model parameters.
Fluorescence image data can be filtered onto immobile structures in a preprocessing step. Bleaching is also possible. After mapping the visual representation of the adapted model parameters or derived quantities can for example be filtered based on degrees and/or other criteria. For example, filtering can be performed based on threshold values for individual or multiple adapted model parameters of for the ratio of the standard deviation of the model parameters to the model parameter values.
Modifications and variations of the above-described embodiments of the present invention are possible, as appreciated by those skilled in the art in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically disclosed. | With the different methods of fluorescence correlation spectroscopy, physical and biological transport processes in or between cells in the microscopic range, for example diffusion processes, can be analyzed. For this purpose, correlations of the fluorescence measurement data are determined for different sample regions and mathematical transport models are adapted thereto. Erroneous fluorescence correlation analyses were previously identified on the basis of the properties of the adapted model function parameters and were discarded. The a-priori knowledge necessary for the identification had to be obtained in time-consuming series of tests. With the invention, sample properties can be determined in a simpler, quicker and more exact way from fluorescence correlations. A suitability degree for one or more regions of the sample is determined for a correlation evaluation, describing quantitatively the information content of the respective region, or the error to be expected from a correlation evaluation, and can thus already be used before a correlation evaluation as a criterion for filtering/selecting the respective region. In this way, elaborate correlation calculations can be dispensed with in non-informative sample regions. | 6 |
REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 11/143,353, entitled PORTABLE WATER DISCHARGING AMUSEMENT DEVICE AND RELATED METHODS, filed on Jun. 2, 2005, now U.S. Pat. No. 7,475,832, which is a continuation-in-part of U.S. patent application Ser. No. 11/136,693, entitled WATER GUN AMUSEMENT DEVICES AND METHODS OF USING THE SAME, filed on May 23, 2005, now U.S. Pat. No. 7,458,485.
FIELD OF THE INVENTION
The present invention relates generally to water discharging devices and, more particularly, to systems adapted to discharge water in a pattern suitable for children to jump into or through during play.
DISCUSSION OF THE BACKGROUND ART
Water play toys have long been a source of great amusement and recreation value. In summer months in particular, toys which combine action and the use of water have provided diversion and a source of cooling at the same time. It has frequently been a favorite pastime of children to play using lawn sprinklers and the like by turning the sprinklers on and running through them. Even simply turning on a garden hose and squirting play companions has been popular attesting to the fascination that children have for water and water play.
In U.S. Pat. No. 5,297,979 issued to the inventor herein, Alan Amron, on Mar. 29, 1994, there is disclosed a water sprinkler having a housing that is formed into the shape of a dolphin and that includes a plurality of rotating sprinkler heads for providing a spray of water when the device is connected to a typical garden hose. A water-turbine powered mechanism within the housing generates bubbles which are released through an opening at the top of the housing so that children can jump and play within a spray of water having bubbles interspersed therein.
A reaction type of water sprinkling toy is shown in U.S. Pat. No. 3,700,172. Water communicated by a hose to a housing is conducted through a plurality of internal tubes to spray nozzles opening downwardly from the housing. The force of water emitted by the nozzles causes the housing to lift and hover over the surface on which it is placed at rest. As the term implies, the toy of the U.S. Pat. No. 3,700,172 is one which is caused to rise in reaction to the forces encountered as water passes through the outlet nozzles. Other water reaction toys are also known, including that shown in U.S. Pat. No. 3,079,727 and known as the Water Wiggle. The action/reaction principle is also graphically illustrated by a hose having a constricted outlet which writhes like a snake when a source of water pressure is connected to the hose.
Other toys that generate a spray of water for play purposes are disclosed by Janszen, U.S. Pat. No. 4,573,679 and by Stanley, U.S. Pat. No. 4,205,785. Despite the variety of existing water discharging amusement devices, a continuing need exists for amusement devices which are especially suitable for children's play, which are especially attractive to children, which are easy to use, which does not use excessive amounts of water—especially in areas where water conservation is encouraged, and which is inexpensive and effective in distributing a pleasant and satisfying shower of water.
SUMMARY OF THE INVENTION
The aforementioned needs are addressed, and an advance is made in the art, by water discharging amusement devices that incorporate a housing defining an interior chamber, an inlet conduit dimensioned and arranged to receive water from a source of pressurized water and to direct received pressured water into the interior chamber, a rotatable nozzle assembly dimensioned and arranged to spin while receiving pressurized water from the interior chamber and to eject a substantially spiral stream of water as it spins, and a drive assembly disposed within the chamber and dimensioned and arranged to convert linear forces imparted by pressurized water arriving via the inlet into rotary forces for rotating the rotatable nozzle.
In accordance with an illustrative embodiment of the invention, the drive assembly is disposed proximate said inlet and comprises a turbine including a rotatable disk having a plurality of vanes defined thereon. The inlet conduit may include a first portion defining a first bore having a first diameter dimensioned for threaded engagement with a garden hose and a second portion defining a second bore having a second diameter substantially smaller than the first diameter, the second portion operating as a capillary tube to limit a rate at which water enters the interior chamber and impinges upon the vanes of the turbine.
Depending upon the orientation and position of the discharge opening of the nozzle assembly relative to the orientation and position of the inlet, it may be necessary to incorporate additional elements in the drive assembly. For example, if the axis of nozzle rotation is transverse to an axis defined by the inlet flow path, the drive assembly may further include a driven gear wherein the periphery of the driven gear and the turbine may be defined with corresponding teeth. In accordance with such an implementation, the driven gear includes a shaft dimensioned and arranged to extend through a bore in a sidewall of the housing and to freely rotate within that bore. The shaft is coupled to the rotatable nozzle assembly for rotation therewith and defines a discharge conduit extending therethrough for establishing fluid communication between the interior chamber and the discharge opening of the rotatable nozzle assembly.
Water discharging devices constructed in accordance with the present invention may be realized in a variety of configurations. For example, in sprinkler embodiments, the housing may be configured as a base dimensioned and arranged to support the rotatable nozzle assembly in a substantially vertical orientation. This results in an upwardly directed spiral stream of water which is attractive and interesting to children during play. Other possible configurations include hand-held, hose end nozzles, wherein the device further includes a valve selectively operable between a first position permitting flow of water from the discharge opening of the rotary nozzle assembly and a second position preventing flow of water from the discharge opening. The hand held nozzle configurations of the present invention further include a hand operated trigger dimensioned and arranged to manipulate the valve into either of the first position and the second position.
Amusement devices constructed in accordance with the aforementioned illustrative sprinkler embodiments may include two or more rotatable nozzle assemblies, each being adapted to rotate about a correspondingly different axis of rotation. As will be readily appreciated by those skilled in the art, such an arrangement may be readily achieved using the disk member of the turbine to drive a plurality of driven gear members, with each gear member defining a separate discharge conduit as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features and advantages of the present invention would be better understood by reference to the detailed description which follows, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a side elevation view depicting a water discharging amusement device constructed in accordance with an illustrative water sprinkler embodiment of the present invention, the device being equipped with a nozzle assembly adapted to rotate automatically, as water is discharged, to produce an upwardly directed helix of water;
FIG. 2 is an exploded view depicting the internal construction of the exemplary embodiment of FIG. 1 ;
FIG. 3A is an isometric perspective view depicting a water discharging amusement device constructed in accordance with an illustrative hand-held, hose-end nozzle embodiment of the present invention, the device being equipped with a nozzle assembly adapted to rotate automatically, as water is discharged, to produce, for example, a laterally directed helix of water;
FIG. 3B is a frontal perspective view of the embodiment depicted in FIG. 3A
FIG. 4 is a perspective view depicting an exemplary rotating nozzle assembly utilized in the embodiment of FIG. 3A ;
FIG. 5 is a broken apart, perspective view depicting the internal construction of an exemplary, rotating nozzle assembly for use in realizing the illustrative embodiment of FIG. 3A ;
FIG. 6 is a cross sectional view of the exemplary rotating nozzle assembly of FIGS. 5 and 5 , taken across the plane IV-IV depicted in FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
The accompanying Figures and this description depict and describe embodiments of a water sprinkler amusement device in accordance with the present invention, and features and components thereof. The present invention also encompasses a method of making and using embodiments of the amusement device. As used herein, the phrases or terms “water discharging device,” “sprinkler,” “water discharging amusement device” and the like are intended to encompass a structure or structures configured to automatically project, throw, squirt, launch or shoot water upwardly or laterally into the air so that it falls down upon a child during play, and which can be operated when attached to the end of a garden hose. It should also be noted that any references herein to front and back, right and left, top and bottom and upper and lower are intended for convenience of description, not to limit the present invention or its components to any one positional or spatial orientation.
With regard to fastening, mounting, attaching or connecting components of the present invention to form the water discharging amusement device as a whole, unless specifically described otherwise, such are intended to encompass conventional fasteners such as screws, nut and bolt connectors, threaded connectors, snap rings, detent arrangements, clamps such as screw clamps and the like, rivets, toggles, pins and the like. Components may also be connected by adhesives, glues, welding, ultrasonic welding, and friction fitting or deformation, if appropriate, and appropriate liquid and/or airtight seals or sealing devices may be used. Unless specifically otherwise disclosed or taught, materials for making components of the present invention may be selected from appropriate materials such as metal, metallic alloys, natural and man-made fibers, vinyls, plastics and the like, and appropriate manufacturing or production methods including casting, pressing, extruding, molding and machining may be used.
Turning now to the drawings, in which like elements are denoted by like reference numerals throughout the several views, a first illustrative embodiment of a water discharging amusement device 10 in accordance with the present invention is depicted in FIGS. 1 and 2 . The embodiment of FIGS. 1 and 2 include an elongated housing or body 12 having defined therein an interior chamber indicated generally at 14 . In the illustrative embodiment, housing 12 has an animal shape having a plurality of downwardly depending legs 13 dimensioned and arranged for stable placement of housing 12 on a lawn or other suitable surface (not shown). An inlet conduit 15 has a first end 15 a dimensioned and arranged for threaded engagement with the end of a garden hose H and a second end 15 b which enters chamber 14 . A bore extending through conduit 15 has a first portion 16 a having a first interior diameter conforming, more or less, to the diameter of the interior bore of the garden hose. In the exemplary embodiment of FIGS. 1 and 2 , the bore has a second portion 16 b ( FIG. 2 ) having a second diameter which is selected so as to function as a capillary tube. Illustratively, portion 16 b may be on the order of about 0.062 inches in diameter. This arrangement has been found to limit the rate of water flow, over an expected range of municipal water pressures, to a level that preserves the spiral appearance of the discharge pattern. In that regard, it should also be noted that the inventor herein has observed that an advantageous arrangement is achieved when the diameter of portion 16 b is less than the diameter of the orifice through which water is ejected by the device. When using a capillary tube section diameter of 0.062 inches, for example, advantageous results have been achieved with a nozzle orifice diameter of 0.074 inches.
As best seen in FIG. 2 , it will be seen that water entering chamber 14 via capillary tube section 16 b impinges upon the vanes 18 of turbine 20 . Essentially, the purpose of turbine 20 is to convert the linear forces imparted by water entering via capillary tube section 16 b into rotary forces suitable for rotating a rotatable nozzle assembly indicated generally at reference numeral 24 . To that end, the peripheral surface of a disk section 26 of turbine 20 defines a series of teeth 28 adapted to engage with corresponding teeth 30 on the peripheral surface of a driven gear assembly 32 that is secured to rotatable nozzle assembly 24 . Accordingly, as turbine 20 rotates, driven gear assembly 32 and nozzle assembly 24 also rotate. To allow water to flow from within chamber 14 to the discharge opening 34 of nozzle assembly 24 , driven gear assembly includes a shaft 36 that defines an axial discharge conduit 38 . This arrangement permits water to pass from chamber 14 directly to the nozzle assembly 24 .
With continuing reference to FIG. 2 , it will be seen that nozzle assembly 24 comprises a cap member 40 which is secured to the distal end 42 of shaft 36 . Within cap member 40 is a discharge tube 44 having a spherical inlet end 46 which is pivotably received within cap member 40 and adapted for pivotable movement therewithin. Such an arrangement permits the divergence of the spiral water stream P ( FIG. 1 ) ejected by nozzle assembly 24 to be quickly and easily adjusted by the user. Specifically, pivoting nozzle end 34 of discharge tube 44 outwardly (i.e., so as to diverge away from the axis of rotation of assembly 24 ) produces a “tornado” effect in which the layers of water in path P expand outwardly as they rise vertically. The greater the angle of divergence, relative to a vertical axis of rotation, the wider the diameter achieved by each layer of water in the spiral path P. Even greater divergence may be achieved by offsetting the discharge path relative to the axis of rotation. It should be noted that although only one nozzle assembly is depicted in FIGS. 1 and 2 , it will be readily appreciated by those skilled in the art that additional nozzle assemblies, as nozzle assembly 24 , may be readily incorporated into the device 10 .
Turning now to FIGS. 3A-7 , there is shown a hand-held, hose-end nozzle device 100 constructed in accordance with a second illustrative embodiment of the invention. With initial reference to FIGS. 3A and 3B , it will be seen that device 100 comprises a conventional hose end adaptor assembly indicated generally at 110 having a body or housing 102 that includes a handle section 104 and a barrel portion 106 . The conventional hose adaptor assembly 110 employed in the illustrative embodiment of FIGS. 3A and 3B is substantially as shown and described in U.S. Pat. No. 5,303,868, issued to Kroll on Apr. 19, 1994 and entitled Hose Nozzle, the disclosure of which is expressly incorporated herein by reference. It should, however, be emphasized that any conventional hose adaptor assembly operative to receive water via a source of municipally pressurized water by way of a hose attachment will suit the purporses of the present invention. Indeed, many conventional hose end nozzle assemblies incorporate not only a threaded inlet or proximal end, but also a threaded discharge or distal end. The latter configurations are especially suited for kit forms of the invention, in which a rotatable nozzle assembly is realized as an adaptor dimensioned and arranged for threaded engagement onto the distal end of a conventional hose end nozzle, rather than as an integrated assembly. In any event, and with continued reference to FIGS. 3A and 3B , water is introduced via an inlet opening 108 dimensioned and arranged for threaded engagement with the end of a conventional garden hose H. Depression of a conventional spring biased trigger, as trigger 110 , opens a conventional, normally closed valve (not shown), thereby allowing water through an internal conduit 112 ( FIG. 4 ) that passes through the handle toward a distal end 114 of barrel portion 106 .
As in the case of the embodiment of FIG. 1 , the embodiment of FIGS. 3A and 3B employs a rotating nozzle 124 . While trigger 110 is in the “on” or an “intermediate” depressed position, nozzle assembly 124 rotates and water being discharged through a discharge outlet 126 thereof assumes a spiral trajectory in any direction the user chooses to aim barrel portion 106 . Automatic rotation of nozzle assembly 124 to produce a spiral discharge effect can be achieved in a variety of ways. By way example, discharge outlet 126 of nozzle assembly 124 may be dimensioned and arranged to impart a nozzle reaction force—that is offset relative to the axis of nozzle assembly rotation—as the stream of water is discharged. Even a relatively small angle of inclination of the discharge stream relative to a plane orthogonal to the rotational axis of the nozzle assembly is sufficient to induce rotation of the nozzle assembly.
In accordance with an especially preferred embodiment of the present invention, however, the force for spinning nozzle assembly 124 is provided via the pressurized water stream traversing conduit 112 . An exemplary structure adapted to utilize this force is depicted in FIGS. 4-6 and will now be described in detail. As seen in FIG. 4 , nozzle assembly 124 comprises a first section 136 and a second section 138 which, when assembled into the configuration shown in FIGS. 5 and 6 , define an interior cavity 140 ( FIG. 6 ) within which is disposed a flow diverter assembly indicated generally at 142 .
With reference to both FIGS. 4 and 6 , it will be seen that flow diverter assembly 142 has a proximal end 144 dimensioned and arranged to receive and retain the distal end 146 of conduit 112 . Conduit 112 and flow diverter assembly 142 are fastened together in a conventional manner such, for example, as by a suitable adhesive. As such, fluid diverter assembly 142 is not a moving part but, rather, is stationary despite being disposed within interior cavity 140 . Fluid exiting the discharge orifice 128 of conduit 112 enters an inlet 148 defined at the proximal end 144 of flow diverter assembly 142 . The center of first section 136 defines an axial opening through which proximal end 144 is inserted. Locking rings indicated generally at 152 and 154 in FIG. 6 prevent axial movement of diverter assembly 142 relative to first section 138 . A first bushing indicated generally at 156 a enables first section to rotate about an axis defined by flow diverter assembly 142 . To prevent water from leaking out of interior cavity 140 , O-rings or other suitable gaskets may be utilized at the interface between the interior surface of bore 136 a of first section 136 and the exterior surface of diverter assembly 142 . A second bushing, indicated generally at 156 b is provided to retain and support nozzle assembly 124 at the distal end 114 of device 100 while still allowing it to freely rotate relative thereto.
Defined within the interior axial surface 137 of second section 138 are a plurality of vanes 139 . As best seen in FIG. 4 , water entering inlet opening 148 of flow diverter assembly 142 exits via a pair of exit openings indicated generally at 160 and 162 . As will be readily appreciated by those skilled in the art, exit opening 160 and 162 are dimensioned and arranged so as to cause corresponding jets of liquid to impinge upon the surfaces of vanes 139 , thereby initiating rotation of first section 136 and second section 138 .
In the illustrative embodiment depicted in FIG. 3A-6 , it will be seen that water exits the spinning nozzle assembly 124 via a discharge opening 140 at the distal end of pivotably movable nozzle member 134 . As described in connection with the embodiment of FIGS. 1 and 2 above, such a structure is advantageous in that it gives the user a high degree of flexibility in defining the diameter and/or pitch of the spiral stream which is discharged. Of course, if such flexibility is not a design constraint, then it is of course possible to integrally form a nozzle member directly as part of second section 138 .
It is believed that the disclosure set forth above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in illustrative form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. By way of illustration, and as indicated earlier, kit forms of the invention may be realized by coupling diverter assembly within a cylindrical adaptor (not shown) having internal threads at one end for securing to the end of a conventional hose nozzle assembly and suitable structure (e.g., bushings and locking rings) on the other end for retaining first section 136 in a way that permits first section 136 to freely rotate. Such a configuration is advantageous since it allows a rotatable nozzle assembly as assembly 124 to be implemented with a wide variety of conventional hose end nozzle structures, and to be attached and detached as desired.
The subject matter of the inventions includes all novel and non-obvious combinations and sub-combinations of the various elements, features, functions and/or properties disclosed herein. Similarly, where the claims recite “a” or “a first” element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.
Inventions embodied in various combinations and sub-combinations of features, functions, elements and/or properties may be claimed in this or a related application. Such claims, whether they are directed to a different invention or directed to the same invention, whether different, broader, narrower or equal in scope to any original claims, are also regarded as included within the subject matter of the inventions of the present disclosure. | A water discharging amusement device incorporates a housing defining an interior chamber, an inlet conduit dimensioned and arranged to receive water from a source of pressurized water and to direct received pressured water into the interior chamber, a rotatable nozzle assembly dimensioned and arranged to spin while receiving pressurized water from the interior chamber and to eject a substantially spiral stream of water as it spins, and a drive assembly disposed within the chamber and dimensioned and arranged to convert linear forces imparted by pressurized water arriving via the inlet into rotary forces for rotating the rotatable nozzle. | 1 |
BACKGROUND OF THE INVENTION
[0001] Locomotion function is one of the important behavior parameters in animal research for human neurodegenerative diseases such as Parkinson's disease, Huntington's disease, and Alzheimer's disease. Neurodegenerative animal models have been well-established in rodents. Animal models with such diseases exhibit characteristic motoric deficits including declined movement activity, decreased movement speed, and reduced traveling distance. With an effective drug treatment, the animal locomotion function could be recovered to a great extent. Therefore, automated logging of the animal's locomotion function is essential in the pharmaceutical laboratory.
[0002] A number of inventors proposed methods to detect laboratory animal dynamic motion activity. The Stigmark et al U.S. Pat. No. 3,656,456 provides a system to monitor motion activity by detecting electrode capacity imbalance across a transformer bridge which results from animal movement in the environment. The Castaigne U.S. Pat. No. 3,540,413, the Vajnoszky U.S. Pat. No. 3,633,001and the Meetze U.S. Pat. No. 3,974,798 disclose methods to detect laboratory animal motion activities by measuring the conductance of animals in contact with electrodes.
[0003] Methods of detecting laboratory animal locations are also provided by many other inventors. The earlier method disclosed by U.S. Pat. No. 3,304,911(Hakata, et al) uses a pair of movable infrared light receivers to track animal locations in a square field. Salmons U.S. Pat. No. 3,439,358 utilizes multiple receiving antennae to detect animal location using the antennae's proximity to the animal. Other inventors report methods to detect animal location in a rectangular cage by employing infrared transmitter and receiver arrays; these inventors include Czekajewski, et al (U.S. Pat. No. 4,337,726), Mandalaywala, et al (U.S. Pat. No. 4,574,734), Matsuda (U.S. Pat. Nos. 5,608,209 and 5,717,202) and Young (U.S. Pat. No. 5,915,332). Sakano U.S. Pat. No. 4,968,974 also proposes an infrared position detection system for an animal in a cylindrical cage.
[0004] An advantage of the present invention is the provision of an inexpensive apparatus that can easily adapt to the conventional laboratory animal cage, the so-called animal home cage, without any special enclosures or modifications to the existing cage.
BRIEF SUMMARY OF THE INVENTION
[0005] It is an objective of the present invention to provide an apparatus which is inexpensive, can easily adapt to a conventional animal cage, and has a measurement method for determining the laboratory animal's location and movement in the cage. The apparatus is comprised of a plate placed on the bottom of the cage whereon multiple electrode pairs are configured as a two-dimensional electrode array, an electronic circuit detecting and measuring the capacitance between said electrodes, and a microprocessor determining the animal location. The electrodes are connected as rows and columns groups. An electric signal generator in the capacitance detection circuit sends an excitation signal to the electrode array. The capacitance detection circuit receives the signal from each electrode row or column group in a sequential manner. The signals received are amplified, rectified, filtered and sampled by a microprocessor. When the animal is present in the cage and above the electrode plate, the signal on the electrodes induced by the excitation signal is altered due to capacitance change caused by proximity of the animal body.
[0006] The microprocessor compares the signal with the pre-stored reference signal to detect the capacitor change. By determining the capacitance changes among the electrodes, the animal's x-y coordinate can be determined.
BRIEF DESCRIPTION 0 F DRAWINGS
[0007] FIG. 1 is a drawing of an animal enclosure according to teachings of the present invention.
[0008] FIG. 2 illustrates the electrode plate structure.
[0009] FIG. 3 demonstrates the row and column electrode connections.
[0010] FIG. 4 shows some samples of electrode configuration patterns.
[0011] FIG. 5 visualizes the relationship between the electrodes and the capacities resulting from the animal body.
[0012] FIG. 6 is an electronic schematic diagram illustrating the circuitry of an embodiment according to the teachings of the present invention.
[0013] FIG. 7 shows the two configurations of the capacitance detection input and the excitation signal output.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Referring to the Figures, the preferred embodiment of the present invention is described in detail. FIG. 1 , a cage or enclosure 1 , usually made with transparent polymetacrylate-glass (Plexiglas) material, provides the laboratory animal 5 for observation and evaluation a bounded activity space. An electrode plate 10 is placed on the bottom of the cage supported by the fastening stands 3 . The electrode plate 10 and its electrode arrangement will be described in detail later. On the bottom side of the electrode plate are the electronic components 20 and microprocessor 30 for detecting animal location and movement. The cage is open at top and is secured by a top cover 2 made of Plexiglas or metal with ventilation openings and food/water delivery attachments, details of which are beyond the scope of this invention.
[0015] FIG. 2 illustrates the structure of the electrode plate 10 . The rectangular-shaped supporting plate 17 , whose dimensions match those of the animal cage floor, is made of electrical insulating material. The flat electrodes 11 and 12 are laid out on the surface of the supporting plate. The electrodes are insulated from each other and separated by a small predetermined space. Note that the figure is a simplified drawing to illustrate the electrode arrangement, and the dimensions may not be drawn to scale. The electrodes are connected as rows ( 11 ) by the wires 13 and columns ( 12 ) by the wires 14 as shown in FIG. 3 . The electrodes connected in rows are paired with neighboring electrodes connected in columns to form the electrode matrix. Neighboring row-connected and column-connected electrodes may be further intertwined into inter-digitated patterns to increase the sensitivity of animal detection; example embodiments are shown in FIG. 4 a , the comb-like pattern, and FIG. 4 b , the spiral pattern. The intertwined electrodes can be made using the printed circuit board (PCB) technique. The wires 13 connecting the rows of electrodes 11 are further routed to a row multiplexer 21 while the wires 14 connecting the columns of electrodes 12 are further routed to a column multiplexer 22 . As shown in FIG. 2 , a thin insulation layer 18 is on top of the electrode plate to prevent the animal's paws from directly contacting the electrodes and also to physically protect the electrode array from damage by animal paws. An electrical conducting sheet 19 is on the backside of the electrode plate for shielding the electrode plate 10 from interference of other objects which may be close to the bottom of said electrode plate. The electrode plate is connected to the shield signal from the shield signal driver 25 .
[0016] In case the animal is absent from the cage, there is capacity 7 existing in between each electrode and surrounding electrodes as shown on FIG. 5 . When the animal is present in the cage and above the electrode plate, there are capacities 6 in between the electrodes and the animal body. The capacities 6 are in parallel with the original capacity 7 in between the electrodes and as a result, the total capacitance of the electrode under the animal body increases, relative to the capacitances of the surrounding electrodes. By detecting the capacity changes of the electrodes connected in rows, the animal location on the row ordinate can be deduced. Using the same method, by detecting the capacity changes of the electrodes connected in columns, the animal location on the column ordinate can be deduced and thus animal's x and y coordinate on the electrode plate is determined.
[0017] The capacity detection means is shown on FIG. 6 . The electrodes connected in rows through the wires 13 are connected to the multiplexer 21 and the electrodes connected in columns through the wires 14 are connected to the multiplexer 22 . The multiplexer 21 and multiplexer 22 are controlled by the microprocessor 30 in such a way that only one row or one column of the electrodes is routed to the capacity detection circuit 20 at any moment. When the apparatus starts, the first row of electrodes is routed to said capacity detection circuit. Then each row of electrodes followed by each column of electrodes is routed to the capacity detection circuit one by one, separated by a predetermined short time interval. After the last column of electrodes is executed, the procedure repeats again from the first row of electrodes. The time interval in between each route is determined by the capacitance data sampling rate.
[0018] The excitation source of the capacity measurement is the oscillator 29 which generates high purity sine waves at 120 KHz at the preferred embodiment. The excitation wave signal is delivered to the electrode plate through multiplexer 21 and 22 after it is amplified by the amplifier 24 . The signal received from the electrodes is also routed to the amplifier 23 by multiplexer 21 and 22 . The relationship between the excitation signal and the received signal is shown in FIG. 7 a and FIG. 7 b , and will be described later. The amplified received signal is rectified by a rectifier 26 . The rectified signal is then sent to a low pass filter 27 before it is sent to the analog-to-digital converter (ADC) 28 . The low pass filter 27 removes the high frequency interference and limits the signal to a low frequency band representing the animal movement by a predetermined cut-off frequency. The ADC 28 converts the received signal into digital form. The sampling rate of the ADC 28 is at lease twice the cut-off frequency of the low pass filter 27 to avoid the sampling alias. The digitized signal is sent to the microprocessor unit 30 for further analysis. The microprocessor unit contains an associated memory block 31 . The data sampled from each row and each column of electrodes when the cage is empty is stored in the memory as calibration reference. When the animal is present the animal's body sitting on the electrode plate changes the electrodes' capacitance. The microprocessor unit 30 computes the differences between the data derived from the rows and the columns of the electrodes and the corresponding pre-stored reference data on the memory block 31 . A larger difference indicates a larger variation in the capacitance change in the row or the column of the electrodes. The animal's location is determined by measuring the center of mass based on the data difference. To avoid interference from other objects under the electrode plate 10 , the sine wave generated from the oscillator 29 is delivered to the shield layer 19 on the back side of the electrode plate 10 through an amplifier 25 .
[0019] The relationship between the excitation signal from the oscillator amplifier 24 and the currently selected electrode, which is sending back the signal to the capacity detection circuit, may be configured in different ways. The preferred embodiment is shown in FIG. 7 a . The excitation signal from the amplifier 24 is connected to the current selected electrode 15 and the receiving amplifier 23 through a resistor 32 . The other non-active electrodes 16 (not being selected at the moment) are connected to ground. When an animal is present above the currently selected electrode 15 , the capacity between the animal body 2 and the current selected electrode 15 shunts the excitation signal to other grounded electrodes 16 . As a result, the amplitude of the received excitation signal drops at the input of the receiving amplifier 23 , and the microprocessor senses a decreased data value in comparison with the reference data in which no animal is presented. The microprocessor can determine the animal's location based on the x-y coordinate of the electrodes which exhibit the decreased received excitation signal.
[0020] An alternative configuration of the excitation signal and the current selected electrode is shown in FIG. 7 b . Currently selected electrode 15 is connected to the receiving amplifier 23 providing the input signal to the capacity detection circuit. The excitation signal from the amplifier 24 is connected to other non-active electrodes 16 . When the animal is not present, only a small amount of excitation signal is coupled to the selected electrode through the capacity 7 in between the electrodes (see FIG. 5 ). When the animal is present above the selected electrode 15 , the amplitude of the coupled excitation signal delivered to amplifier 23 increases due to the adding of capacity between the animal body and the electrodes. The microprocessor can determine the animal's location based on the x-y coordinates of the electrodes which exhibit the increment of the received excitation signal. | A system for tracking the laboratory animal position and movement in a walled enclosure or cage for observation and evaluation is disclosed. The system consists of a plate placed on the bottom of the cage whereon multiple electrodes are configured as column-row two-dimensional electrode array, an electronic circuit detecting and measuring the capacitance between said electrodes, and a microprocessor determining the animal's location. The electronic circuit repeatedly measures the capacitance between the electrodes in a sequential manner. The animal's location and movement is determined by detecting the changes in capacitance on said plate. | 0 |
FIELD OF THE INVENTION
The present invention relates to an improved apparatus for the wet treatment of fabrics wherein the fabric is driven in rope form through an enclosed, pressurised or unpressurised vessel. The fabric follows a fast outgoing path through a transport duct and a further slow return path through a storage chamber which contains at any time the major portion of the fabric rope being treated and which is constructed in such a way that the portion of cloth stored in said chamber is kept impregnated with a minimum amount of liquor, with a view to being able to work with a low liquor ratio.
DESCRIPTION OF THE PRIOR ART
In the prior art there are known several machines for the wet treatment of fabric in rope form with high or medium (normal) liquor ratios, in which the fabric is driven along by a hydraulic traction means constituted only by a jet means fed with the liquor itself, which may be complemented with mechanical traction means, such as a winch or an endless belt, either in open vessels or in closed vessels adapted for pressurised operation.
There are also known machines in which the fabric movement is effected by a hydraulic traction means constituted by an overflow means fed with the liquor itself, in which case the hydraulic traction is complemented by mechanical traction as in the previous case.
On the other hand, the present applicant developed apparatus wherein the fabric movement is effected by the used of a mixed hydraulic traction means formed, on the one hand, by an overflow means and, on the other hand, by a jet means. These are completely independent and are complemented by a mechanical traction means comprising a winch, either in an open vessel or in a closed vessel for pressurised operation.
Outstanding among the apparatus in which the fabric is driven through the apparatus only with the aid of a jet are those disclosed in U.S. Pat. No. 2,978,291 (Fabringer-Burlington Industries Inc.), C.S.P. No. 318,087 (Gaston County Dyeing Machine Co.) and 3,771,337 (Trullas-Argelich).
Among the apparatus wherein the fabric is driven through the apparatus with the aid of a jet and a winch or endless belt, are those disclosed in U.S. Pat. Nos. 3,587,256 (Alvar-Avesta Jernwerks Aktiebolag) and 3,952,558 (Sven et al. Avesta Jernwerks Aktiebolag), French Pat. Nos. 72.09.648 (Platt) and 74.09.230 (Thies) and those built by the Italian firm MCS under the name of "JET-MR", by Pegg under the name of "FABLO", by Leopoldo Pozzi under the name of "POZZI-FLOW", by Then under the name of "THEN-ECONOMY-FLOW", by Thies under the name of "R-JET" and by Scholl under the name of "COMPACT".
Among the apparatus wherein the fabric is driven through the apparatus with the aid of an overflow means and a winch or the like, there are those disclosed in Spanish Pat. No. 402.434 (Argelich), French Pat. Nos. 72.41.814 (Argelich) and 2,011,982 (Sakai) and U.S. Pat. No. 3,782,138 (Kawasaki).
Finally, among the apparatus wherein the fabric is driven through the apparatus with a completely independent overflow, jet and winch, are those disclosed in Spanish Pat. Nos. 424,689 and 425,022 (Argelich) and U.S. Pat. No. 3,949,580 (Trullas-Argelich).
The improved apparatus of this invention comprises distinguishing features over the prior art apparatus listed above, particularly with respect to the special construction of the storage chamber, for obtaining a low liquor ratio, and of the overflow and jet devices, to obtain a compact monobloc arrangement, allowing a compact, high capacity apparatus to be obtained.
SUMMARY OF THE INVENTION
The object of the invention is to provide an apparatus of the type indicated in which there are disposed in combination a circuit for the fabric and a further circuit for the treatment liquor, wherein the fabric circuit is constituted by the combination of:
(a) a storage chamber for the major portion of the fabric rope, through which the fabric is caused to pass slowly, substantially submerged in the liquor, which chamber is of tubular construction and substantially circular in a vertical plane;
(b) an upper chamber or zone corresponding to one end of the storage chamber, containing means for mechanical traction of the fabric and combined means for mixed hydraulic traction of said fabric; said means for the mechanical traction of the fabric being constituted by a winch; and said combined means for the mixed hydraulic traction of the fabric comprising an overflow means and a jet means;
(c) a substantially horizontal duct associating the said upper zone from the jet means outlet with the other end of the storage chamber;
whereas the liquor circuit comprises a pump means associating at least one lower point of the storage chamber with the combined means for mixed hydraulic traction of the fabric, through a filter and a steam operated heat exchanger.
A further object of the invention is to provide the combined means for the mixed hydraulic drive of the fabric grouped in a single body, having an overflow means followed immediately by a jet means.
Yet a further object of the invention is to provide the combined means for the mixed hydraulic traction of the fabric formed by an overflow chamber in which there is an annular chamber having in its center passage, in an order determined by the direction of circulation of the fabric rope, a funnel means acting as overflow extending into a tubular peripheral apron portion, opposite to and spaced at a constant peripheral distance from a flared, tubular baffle type body having a transverse dimension greater than that of said tubular portion, which it surrounds with a certain degree of clearance determining a peripheral jet opening, through which there is injected inwardly under pressure the treatment liquor introduced into said annular chamber, which liquor mixes with the liquor coming in from overflowing of the overflow chamber level through the upper face of said annular chamber.
A further object of the invention is to make the flowrate of the overflow means adjustable independently of the flowrate of the jet means.
Yet a further object of the invention is to provide for the flowrate of the overflow means to be regulated in terms of the flowrate of the jet means with a view to filling the vacuum caused by the suction, by the Venturi effect, on the upper face of the annular chamber so as to prevent the aspiration of air and subsequent emulsifying thereof with the treatment liquor which would cause an undesirable foam in the fabric treatment.
A further final object of the invention is to locate the filter between the bottom of the storage chamber and the pump means in the treatment liquor circuit vertically at a level allowing it to be cleaned without draining the treatment liquor circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and features of the invention will be disclosed in detail in the following description, taken with the accompanying illustrative drawings in which:
FIG. 1 is a schematic elevation view, in longitudinal section, of an improved apparatus according to the invention, adapted for non-pressurised operation;
FIG. 2 is an elevation view in longitudinal section, of an apparatus according to the invention;
FIG. 3 is a detail in section of the mixed overflow and jet means;
FIG. 4 is a front elevation view of the same apparatus;
FIG. 5 is a plan view of the apparatus;
FIG. 6 is a schematic view of an apparatus according to the invention, adapted for pressurised operation;
DETAILED DESCRIPTION OF THE INVENTION
Generally speaking, according to FIG. 1, the apparatus of the invention comprises a circuit for the circulation of a fabric 1 in the form of an endless rope, formed by a storage chamber 2 of curved tubular semicircular construction in the vertical plane, by an upper chamber 3 corresponding to one end of the chamber 2 and by a substantially horizontal transport duct 4 arranged between the upper chamber 3 and the other end of the chamber 2. A circuit for the treatment liquor 5 comprises a duct 6, having a discharge valve 7, associating the bottom of the chamber 2 with the upper chamber 3, through a vertically extending filter 8, a means comprising a motor 9 and a pump 10 and a heat exchanger 11.
The treatment liquor 5 is held at a level N in the chamber 2, said level being adjustable by the liquor circuit. The filter 8 comprises a vertical chamber, having a cover 8a, wherein the filter medium is contained. Said filter 8 is disposed vertically, its upper edge being at a higher level than level N so that the filter may be cleaned without having to drain the treatment liquor circuit. The upper chamber 3 is provided with a side cover 12 and houses a winch 13 wrapped by the fabric 1. The winch 13 may rotate freely or have its shaft 14 coupled to a group formed by a motor 15, variator 16 and a speed reducer 17, without excluding other variable speed units such as D.C. motors and hydraulic motors.
Within said upper chamber 3 there is an overflow chamber 18 provided with an annular chamber 19, illustrated in the drawings as being rectangular in plan view, said annular chamber 19 having at its top face 20 a funnel means 21 acting as overflow, of inverted truncated pyramid shape and having a tubular, peripheral apron portion 22. Said tubular portion 22 is opposite to and spaced at a constant peripheral distance from a rectangular duct 23 having a flared mouth 24, as a baffle, of such dimensions as to spacedly surround the tubular portion 22 so as to produce an exit 25, disposed as a jet means, for the treatment liquor reaching said annular chamber 19. The treatment liquor is fed through the line 26 to the valves 27 and 28 to feed the overflow chamber 18 and annular chamber 19, via lines 29 and 30 respectively. Duct 23 is extended into a curved portion 31 so as, by way of a section modifying coupling, to continue substantially horizontally in the transport duct 4 of circular section. This terminates in a curved portion directed towards the storage chamber at the opposite end thereof to the said upper chamber 3.
The apparatus is located on a bedplate 33 having a frame 34 and which is provided also with accessories such as a kettle 35 for preparing the liquors, with ducts 36 and 37 towards the liquor circuit. The storage chamber 2 has an overflow 38 for excess liquor, for example in continuous washing processes.
In the present apparatus, the fabric 1 circulates under the effect of the thrust received in the annular chamber 19, without prejudice to the fact that the winch 13, which is power driven, may drive along the fabric wrapped around its periphery. The annular chamber 19 also fills the depression created therein by the Venturi effect that the jet means may create, acting as a hydraulic seal to prevent the liquor from emulsifying with the air and the consequent formation of undesirable foam which is harmful to the treatment. The peripheral jet means 25 located under the overflow means 20 is particularly useful for centering the fabric 1 on its passage through the rectangular duct 23 and through the transport duct 4, as well as for contributing to driving the fabric 1 along through the apparatus.
As shown in FIG. 6, this apparatus may be mounted in a cylindrical vessel 39 which is pressure resistent and provided with a loading door 40 having an airtight seal so as to be able to operate at high pressures.
In all cases, this apparatus may be built according to a system of modules allowing several units to be joined for individual or joint operation, providing a wide range of flexibility and production, since less units may operate whilst maintaining the low liquor ratio. | Apparatus for the wet treatment of fabrics in rope form, wherein the tubular storage chamber is curved according to an arc of a circle in the vertical plane and has at one of the ends thereof means for the mechanical traction of the fabric and joint means for the hydraulic traction thereof. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a national stage application of International Application No. PCT/CA2008/000023 filed Jan. 8, 2008, which claims priority to U.S. Provisional Application 60/883,892 filed Jan. 8, 2007, and the entire contents of each are hereby incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to recovery of hydrocarbon-containing substances from subterranean reservoirs. More particularly, this invention relates to manipulation of vibrational energies directed toward subterranean reservoirs for affecting the viscosities and flows of hydrocarbon-containing substances therein.
BACKGROUND OF THE INVENTION
Significant challenges are associated with the recovery of hydrocarbon-containing substances such as crude oil from subterranean reservoirs. Subterranean reservoirs typically possess convoluted, fractured and crevassed bottom surface topographies wherein significant quantities of crude oil remain in pools that are inaccessible by conventional oil well extraction systems. Numerous strategies and technologies have been developed to increase the efficiency and extent of crude oil recovery from subterranean reservoirs. Such strategies include injecting water or steam or inert gas through well casings into the reservoirs to break up obstacles (i.e., bottom surface formations) impeding the flow of crude oil to the well, or alternatively, to reduce the viscosity of the oil to increase its flowability. Other strategies to increase the flowability of crude oil within subterranean reservoirs include applications of vibrational energies generated by: (a) seismic shock as a resulted of repeatedly dropping and raising a weight within a well casing, or (b) by lowering an ultrasonic wave generating device e.g., a transducer into a well casing and then manipulating the amplitude and frequency of the waves generated. However, significant volumes of crude oil remain inaccessible.
Dynamics of porous media is of intense research concerns in petroleum engineering, geophysics, geotechnical engineering, and civil engineering, and has been extensively studied for decades. Demands from soil mechanics, oil production, modern earthquake and offshore engineering have further motivated the research on the dynamics of fluid-saturated porous media. By introducing the assumptions that the solid skeleton of the porous medium obeys the laws of homogeneous linear elasticity and the fluid obeys Darcy's laws, Biot (1956a, J. Acoust. Soc. Am. 28:168-178; 1956b, J. Acoust. Soc. Am. 28: 179-191) formulated the governing equations for wave propagation in a fully saturated medium. Biot (1956a; 1956b) also proved the existence of two compressional waves, namely the first and second compressional waves, and one rotational wave in a porous medium fully saturated by fluid. The first compressional wave is also known as the fast wave that is very similar to the compressional wave in an elastic medium, for which the displacements of solid and fluid are in phase. The second compressional wave is usually named as slow wave that has a strongly dispersive characteristic, for which the displacements of fluid and solid are out of phase. Following Biot's theory, Vardoulakis and Beskos (1986, Mech. Comp. Mat. 5: 87-108) developed a theory describing wave propagation in a three-phase porous medium which is applicable to partially-saturated materials. White (1975, Geophysics, 40: 224-232) demonstrated that wave velocity and attenuation are substantially affected by the presence of partial saturation, depending mainly on the size of the gas pockets (saturation), frequency, permeability and porosity of the media. Bardet and Sayed (1993, Soil Dynamics and Earthquake Engineering, 12: 391-402) provided exact and approximate expressions for the velocity and attenuation of the compressional waves within nearly fully saturated poroelastic media.
Recently, numerous research works are performed to improve Blot's theory and to broaden the applications of Biot's theory. Gurevich et al. (1999, Transport in Porous Media, 36: 149-160) utilized experiment and simulation methods to verify Biot's theory. Investigation on the scattering of a fast compression wave by an inhomogeneity in a fluid-saturated medium was presented by Berryman (1985, J. Math. Physics, 26: 1408-1419), who proved that there would be three scattering waves, namely a fast compression wave, a slow compression wave, and a shear wave. The properties of elastic waves in a non-Newtonian (Maxwell) fluid-saturated porous medium were studied by Tsiklauri and Beresnev (2003, Transport in Porous Media, 53: 39-50). It is generally accepted that the wave will attenuate due to the presence of the pore fluid in the porous media. Wave velocities and attenuation are two key aspects of the waves in porous media, since they are important in analyzing the dynamic response of the media with respect to the properties of the media and the wave sources, such as viscosity, frequency and porosity. Hamidzadeh and Luo (2000, Vibration and Control of Continuous Systems 107: 39-44) investigated the dynamic response of the surface of an elastic soil medium which was excited by a vertical harmonic concentrated force by using a semi-analytical method. Based on Biot-type three-phase theory, Pham et al. (2002, Geophys. Pros. 50: 615-627) presented the wave velocities and quality factors of clay-bearing sandstones as a function of pore pressure, frequency and partial saturation. A dispersion coefficient was introduced to reflect the friction between the fluid and solid in a porous medium. Extensional wave attenuation and velocity measurements on high permeability Monterey sand were performed by the authors over a range of gas saturations for imbibition and degassing conditions. The result showed that partially-saturated sands under moderate confining pressure can produce strong intrinsic attenuation for extensional waves. It was found in the study that the velocities show a gradual decrease with increasing water saturation, followed by a sharp increase at near full saturation.
In the current literature, however, there are very few studies focusing on investigating the relative displacements between the fluid and solid in a porous medium fully-saturated by Newtonian fluid. Furthermore, the prior art in this field postulates a single energy source existing in the field being considered.
Governing Equation Development
The following nomenclature is used in the prior art section and invention disclosure sections herein:
C 1 , C 2 —refer to the amplitudes of the waves propagating in solid and fluid respectively; d j —refers to the distance from a source to the origin; e—refers to the volume strains of solid; exp(•)—refers to an exponential function; H—refers to an introduced physical parameter; H 0 (1) (•)—refers to a zero-order Hankel function of the first kind; K b —refers to the bulk modulus of the skeletal frame; K f —refers to the bulk modulus of the fluid; K s —refers to the bulk modulus of the solid; l—refers to a wave number; p—refers to fluid pressure; r—refers to the distance from a point in the field to a source; r—refers to a radius coordinate in a polar system; r j —refers to the distance from a point P to the j th wave sources; s ij —refers to the stresses acting on the fluid of a porous medium; t—refers to time; u—refers to the displacement vector of a fluid; u 0j , U 0j —refer to the displacements of the and fluid of the j th source respectively (j=1, 2, . . . , n); u 0j , U 0j —refer to the displacement vectors of solid and fluid excited by the j th source respectively (j=1, 2, . . . , n); U—refers to the displacement vector of a solid; V 1 —refers to the dilatation wave velocity with respect to a first compressible wave; V 2 —refers to the dilatation wave velocity with respect to a second compressible wave; V c —refers to the ratio of H and ρ; V—refers to the reference wave velocity; x, y—refers to the coordinates of a Cartesian coordinate system; z j —refers to an introduced complex variable; α—refers to the coefficient related to porosity; δ ij —is the Kronecker symbol; ε—refers to the volume strains of a fluid θ—refers to the angular coordinate in a polar system μ s —refers to the shear modulus of a material; ν s —refers to the Poisson ratio of a solid; ξ—refers to the ratio between reference velocity and wave velocity; ξ I , ξ II —refers to roots; ρ—refers to a density parameter; ρ 11 , ρ 12 , ρ 22 —refers to the density terms of a porous medium; ρ f —refers to the mass density of a fluid; ρ s —refers to the mass density of a solid; σ ij —refers to the total stresses of a porous medium; σ ij s —refers to the stresses acting on the solid frame of a porous medium; φ—refers to the porosity of a medium; φ s ,—refers to the scalar potential of a solid; φ f —refers to the scalar potential of a fluid; ψ f —refers to the vector potential of a solid; ψ s —refers to the vector potential of a fluid; ω—refers to the frequency of a wave; and ∇, ∇ 2 —refers to Laplacians.
Biot's theory provides a framework for analyzing the wave propagation in porous media. In Biot's most representative papers in this field (Biot, 1956a, b), the fluid in porous medium is assumed to be compressible and may flow relative to the solid. To derive the wave equations in low frequency range, the following assumptions are made:
(1) the relative motion of the fluid in pores is a laminar flow which follows Darcy's law; (2) the elastic wavelength of the wave traveling in the porous media is much larger than that of the unit solid-fluid element; (3) the size of the unit element is geometrically large in comparison with that of the pores.
Some other basic assumptions in elastic mechanics are also employed, such as homogeneity and isotropy of the porous media material and the impervious of the pore wall, as stated in Biot's studies (Biot, 1956a).
Generally, the stresses acting on a porous medium can be separated into two parts: one is on the solid frame which can be written as σ ij s ; the other is on the fluid represented by s ij =−φpδ ij . Thus the total stresses are expressed by: σ ij =σ ij s +s ij . Where φ is the porosity of the medium; p is the fluid pressure; δ ij is Kronecker symbol; the negative sign existing in the equation is for the association of directions between fluid pressure and stress. Starting with the above stress expressions of a porous medium and by employing the force equilibrium relation, the dynamics equations of a porous medium can be written as:
{
N
∇
2
u
+
∇
[
(
A
+
N
)
e
+
Q
ɛ
]
=
∂
2
∂
t
2
(
ρ
11
u
+
ρ
12
U
)
+
b
∂
∂
t
(
u
-
U
)
∇
[
Qe
+
R
ɛ
]
=
∂
2
∂
t
2
(
ρ
12
u
+
ρ
22
U
)
-
b
∂
∂
t
(
u
-
U
)
(
1
a
,
b
)
The coefficient b is related to Darcy's coefficient of permeability k by
b = μϕ 2 k ( 2 )
where, μ is the fluid viscosity and φ is the porosity of the medium.
In Eq. (1), u and U are the displacement vectors of fluid and solid respectively, which consist of the quantities and directions of the displacements. While e and ε are the volume strains of the solid and fluid respectively with the expressions: e=∇·u, ε=∇·U·ρ 11 , ρ 12 and ρ 22 are density terms, which can be expressed as: ρ 11 =(1−φ)ρ s , ρ 22 =φρ f , ρ 12 =−(α−1)φρ f , while ρ s is the mass density of the solid grains, ρ f is the mass density of the fluid in pores, α=(½)[φ −1 +1], φ is the porosity of the medium. A, N, Q and R are the physical parameters of the medium. A and N are similar as Lame coefficients in elastic theory. N represents the shear modulus of the medium; R is a measure of pressure on the fluid required to drive a unit volume of fluid into the porous medium. Q describes the coupling between the volume change of solid and that of fluid. The expressions for A, N, Q and R will be given in following section.
Based on Eq. (1), Biot (1956a; 1956b) presented the expressions for three waves existing in a porous medium in the form of the volume strain. However, it is not convenient to quantify the displacements from volume strains, especially when a two- or three-dimensional domain is considered. Accordingly, the detailed description for deriving the waves expressions in the form of displacement will be present.
Applying Helmholtz decomposition to the displacement vectors of solid and fluid, respectively:
{ u = grad ( φ s ) + curl ( ψ s ) U = grad ( φ f ) + curl ( ψ f ) ( 3 a , b )
where φ s and φ f are scalar potentials of solid and fluid respectively, ψ s and ψ f are vector potentials for the displacements of solid and fluid. ψ s and ψ f also satisfy the conditions: ∇·ψ s =0 and ∇·ψ f =0.
For P-wave, also named compressional wave, the displacement is corresponding to the scalar potentials, without rotation, that implies ∇×u=0. For S-wave, also known as rotational wave or shear wave, the displacement is due to vector potentials, ∇·u=0. Substituting Eq. (3) into Eq. (1), and rearranging the terms according to the scalar and vector potentials, as Lin et al. (2001, Report No. CE 01-04, Los Angeles, Calif., USA) did in their research, two sets of equations can be obtained corresponding to scalar potentials and vector potentials of the fluid and solid. Thus, the expressions for P- and S-waves can be given as:
For P-wave:
{ ∇ 2 ( P φ s + Q φ f ) = ∂ 2 ∂ t 2 ( ρ 11 φ s + ρ 12 φ f ) + b ∂ ∂ t ( φ s - φ f ) ∇ 2 [ Q φ s + R φ f ] = ∂ 2 ∂ t 2 ( ρ 12 φ s + ρ 22 φ f ) - b ∂ ∂ t ( φ s - φ f ) ( 4 a , b )
For S-wave:
{ N ∇ 2 ψ s = ∂ 2 ∂ t 2 ( ρ 11 ψ s + ρ 12 ψ f ) + b ∂ ∂ t ( ψ s - ψ f ) 0 = ∂ 2 ∂ t 2 ( ρ 12 ψ s + ρ 22 ψ f ) - b ∂ ∂ t ( ψ s - ψ f ) ( 5 a , b )
in which, P=A+2N is an introduced variable. Eqs. (4) and (5) are the governing equations of the waves propagating in porous media in terms of displacement potentials. These make it available to study the compression waves and shear wave separately or jointly in analyzing waves propagating in porous medium.
As in the case of purely elastic waves, the body waves can be separated into uncoupled rotational and dilatational waves. For P-wave, to get the governing equations expressed in the form of displacements, applying the divergence operation to Eq. (4), the equations for dilatational waves can be obtained in the following form:
{
∇
[
∇
2
(
P
φ
s
+
Q
φ
f
)
]
=
∇
[
∂
2
∂
t
2
(
ρ
11
φ
s
+
ρ
12
φ
f
)
]
+
∇
[
b
∂
∂
t
(
φ
s
-
φ
f
)
]
∇
[
∇
2
(
Q
φ
s
+
R
φ
f
)
]
=
∇
[
∂
2
∂
t
2
(
ρ
12
φ
s
+
ρ
22
φ
f
)
]
-
∇
[
b
∂
∂
t
(
φ
s
-
φ
f
)
]
(
6
a
,
b
)
Let φ be a general displacement scalar potential and u a general displacement vector. For P-wave, the displacement vector u is just related to the scalar potential φ by:
u=∇φ (7)
The scalar potential φ also has the following property:
∇(∇ 2 φ)=∇[∇·(∇φ)]=∇×[∇×(∇φ)]+∇ 2 (∇φ)=∇ 2 (∇φ) (8)
Therefore, with equations of Eqs. (7) and (8), the governing equations of Eq. (4) for the dilatation waves can be written in the form of displacements as:
{ ∇ 2 ( Pu sp + QU fp ) = ∂ 2 ∂ t 2 ( ρ 11 u sp + ρ 12 U fp ) + b ∂ ∂ t ( u sp - U fp ) ∇ 2 [ Qu sp + RU fp ] = ∂ 2 ∂ t 2 ( ρ 12 u sp + ρ 22 U fp ) - b ∂ ∂ t ( u sp - U fp ) ( 9 a , b )
in which, the subscript ‘s’ represents the displacement of solid, ‘f’ represents the displacement of the fluid, ‘p’ represents the displacement due to the P-wave. In Eq. (9), the parameters of material, P, Q, R can be expressed as (Plona et al., 1984 , IN Physics and Chemistry of Porous Media, Johnson and Sen, Eds. American Institute of Physics, New York, pp. 89-104; Biot et al., 1957, J. Appl. Mech. 24: 594-601; Lin et al., 2001, Report No. CE 01-04, Los Angeles, Calif., USA):
P = ( 1 - ϕ ) [ 1 - ϕ - K b K s ] K s + ϕ K s K f K b 1 - ϕ - K b K s + ϕ K s K f + 4 3 N ( 10 ) Q = [ 1 - ϕ - K b K s ] ϕ K s 1 - ϕ - K b K s + ϕ K s K f ( 11 ) R = ϕ 2 K s 1 - ϕ - K b K s + ϕ K s K f ( 12 )
in which, φ is the porosity of the porous medium; K f , K s , K b , N are property parameters of the material. K f is the bulk modulus of the fluid; K s is the bulk modulus of the solid; K b is bulk modulus of the skeletal frame; N is the shear modulus of the skeletal frame. Eq. (9) are the governing equations for P-wave propagating in the porous medium. It should be noted that the wave equations are all written in terms of displacements of solid and fluid. The governing equations in terms of displacement for S wave also can be obtained by applying the curl operator to Eq. (5).
SUMMARY OF THE INVENTION
The exemplary embodiments of the present invention, at least in preferred forms, are directed to methods, apparatus and systems for manipulating the mobility and fluidity of hydrocarbon-containing substances, and maneuvering the flows of mobilized hydrocarbon-containing substances within and about subterranean reservoirs.
According to a preferred embodiment of the present invention, there is provided a method for increasing the mobility and fluidity of a hydrocarbon-containing substance thereby increasing its flowability in a subterranean reservoir by providing a plurality of spaced-apart electronically cooperating three-dimensional sources of controllably manipulable vibrational energy directed at the subterranean reservoir to affect the mobility and flows of hydrocarbon-containing substances therein. The plurality of three-dimensional energy sources may be spaced apart as follows: (a) a plurality of three-dimensional sources of controllably manipulable vibrational energy situated on the ground surface above a subterranean reservoir; (b) a plurality of three-dimensional sources of controllably manipulable vibrational energy spaced apart underneath the earth's surface e.g., in two or more spaced-apart well bores drilled into and/or about a subterranean reservoir; and (c) a plurality of spaced-apart three-dimensional sources of controllably manipulable vibrational energy comprising at least one source situated above ground and at least one source situated below the earth's surface. It is preferred that at least three spaced-apart electronically cooperating ground surface sources of controllably manipulable vibrational energy are provided. It is suitable to provide more than three spaced-apart electronically cooperating sources of controllably manipulable vibrational energy for certain applications of the present invention disclosed herein.
According to one aspect, the plurality of ground surface sources of controllably manipulable vibrational energy directed at the subterranean reservoir are positionally triangulated above and about the subterranean reservoir. Suitable vibrational energy includes seismic waves and ultrasonic waves. Each of the sources of controllably manipulable vibrational energy is provided with an apparatus configured for precisely maneuvering and targeting the direction of the vibrational energy emitted toward a selected point in the subterranean reservoir. An exemplary source of controllably manipulable vibrational energy is a seismic apparatus. Each seismic apparatus is provided with electronic means for precisely modulating the frequency and amplitude of the vibrational energy emitted therefrom. The seismic apparatus are configured to communicate with and cooperate with an electronic seismic control device.
According to another aspect, there is provided a seismic apparatus configured for controllably and directionally emitting vibrational energies precisely directed toward a target portion of a hydrocarbon-containing substance within a subterranean reservoir, said vibrational energies comprising pluralities of seismic waves having electronically manipulable frequencies and amplitudes. Alternatively, the vibrational energies may comprise ultrasonic waves. Optionally, the vibrational energies may comprise pluralities of seismic waves and ultrasonic waves.
According to yet another aspect, the seismic apparatus is configured to generate vibrational energies comprising waves having electronically manipulable frequencies and amplitudes. The seismic apparatus comprises a wave-generating device having an emitting portion which can be controllably manipulated in a rotatable and/or pivotable manner to provide precise focusing and aiming at target zones within a subterranean structure, e.g., a reservoir.
According to a further aspect, the seismic devices are mountable on a transportable platform. The transportable platform may be configured to be mountable on a flat-bed trailer configured to cooperate with hauling equipment. Alternatively, the transportable platform may be a flat-bed trailer configured to cooperate with hauling equipment. Exemplary hauling equipment includes heavy-duty over-road truck tractors, farm tractors, track-mounted bulldozers, off-road earth moving equipment and the like.
According to another preferred embodiment of the present invention, there is provided software configured for cooperating with an electronic seismic control device configured for affecting the mobility, fluidity, and flow of hydrocarbon-containing substances within and about a subterranean reservoir. The electronic seismic control device may be configured to communicate with and cooperate with a sensor provided for monitoring a subterranean reservoir and physico-chemical properties of hydrocarbon-containing substances therein, and a plurality of vibrational energy generating sources as exemplified by seismic apparatus.
According to one aspect, the software is provided with at least one algorithm configured for communicating with: (a) each of said plurality of vibrational energy generating sources for receiving therefrom electronic data characterizing the frequencies and amplitudes of vibrational energies emitted therefrom, (b) said electronic seismic control device for receiving data therefrom characterizing said manipulation of the frequencies and amplitudes of said vibrational energies, and (c) said sensing apparatus for receiving therefrom electronic data characterizing the fluidity and patterns of flow of materials, said software program configured for processing, analyzing, optimizing, reporting, storing and communicating data received therein from said seismic apparatus, said electronic seismic control device, and said sensing apparatus, said software program further configured to cooperate with said electronic seismic control device for providing thereto electronic data for further controllably manipulating the frequencies and amplitudes of the vibrational energies emitted therefrom each of said plurality of seismic apparatus.
Optimizing the frequency of the vibrational energy directed at a hydrocarbon-containing substance will cause the mobility and fluidity of the substance to increase; in other words, the substance will become more fluid, mobile and controllably flowable. On the other hand, optimizing the amplitude of the vibrational energy directed at a hydrocarbon-containing substance will create a “pushing” effect on the substance thereby urging the substance to flow along and away from the path of vibrational energy emission.
According to another aspect, the software is configured to enable the electronic seismic control device to concurrently communicate individually with each seismic apparatus whereby the frequency and amplitude of the vibrational energy produced by each seismic apparatus can be modulated differently from each of the other seismic apparatus.
According to a further aspect, it is within the scope of this invention for the software to provide means for electronically manipulating: (a) a first seismic apparatus to generate vibrational energies having high frequencies and small amplitudes directed toward a first selected portion of hydrocarbon-containing substances thereby causing the molecules comprising the substance in the selected portion to vibrate and become more fluid, and (b) a second seismic apparatus to generate vibrational energies having relatively lower frequencies and larger amplitudes directed toward a portion of the hydrocarbon-containing substance adjacent the first selected portion thereby exerting a “pushing” effect on the fluidized molecules in the first selected portion thereby creating a flow of the fluidized molecules away from the vibrational energy emitted from the second seismic apparatus.
According to yet another aspect, it is within the scope of this invention for the software to provide means for electronically manipulating: (a) a first seismic apparatus to generate vibrational energies having high frequencies and small amplitudes directed toward a first selected portion of hydrocarbon-containing substances thereby causing the molecules comprising the substance in the selected portion to vibrate and become more fluid, (b) a second seismic apparatus to generate vibrational energies having relatively lower frequencies and larger amplitudes directed toward a portion of the hydrocarbon-containing substance adjacent the first selected portion thereby exerting a “pushing” effect on the fluidized molecules in the first selected portion thereby creating a flow of the fluidized molecules away from the vibrational energy emitted from the second seismic apparatus, and (c) a third seismic apparatus to intermittently generate vibrational energies having relatively lower frequencies and larger amplitudes directed toward the same portion of the hydrocarbon-containing substance adjacent the first selected portion thereby exerting a pulsating “pushing” effect on the fluidized molecules in the first selected portion thereby precisely maneuvering the flow of the fluidized molecules away from the vibrational energy emitted from the second seismic apparatus. Furthermore, the software of the present invention may be configured to independently controllably modulate the frequency and amplitude of each seismic apparatus from a very low to a very high frequency and there between concomitantly with a very large to a very small amplitude and there between.
According to a further preferred embodiment of the present invention, there is provided a system for independently manipulating and controlling a plurality, e.g., three seismic apparatus over an extended period of time to first, cooperatively and concurrently emit high-frequency small-amplitude vibrational energies at a portion of a hydrocarbon-containing substance within a subterranean reservoir thereby increasing its fluidity and mobility, then secondly, to controllably modulate the vibrational energy emitted by one of the seismic apparatus to a lower frequency and larger amplitude wavelength thereby exerting a “pushing” effect on the mobilized portion of the hydrocarbon-containing substance which is maintained in a mobilized state by the high frequency small amplitude vibrational energies emitted by the two other seismic apparatus thereby causing it to flow, and thirdly, controllably manipulating a second seismic apparatus to modulate the vibrational energy emitted by one of the seismic apparatus to a lower frequency and larger amplitude wavelength and then to intermittently pulse the vibrational energy to controllably cause directional changes in the flow of the mobilized hydrocarbon-containing substance. It is also within scope of this invention to controllably pivot and rotate the seismic wave generating apparatus to redirect and refocus the target portion of the hydrocarbon-containing substance ahead of the mobilized and flowing portion thereby creating a pathway or channel for the flow. Accordingly, concurrently controllably manipulating and coordinating the direction of the vibrational waves emitted by each of the seismic apparatus enables precise maneuvering of the flow pathways of the mobilized hydrocarbon substance within the subterranean reservoir for example, toward and to wellbores wherein the mobilized hydrocarbon substances can be pumped to the ground surface and stored in above ground holding containments or alternatively transferred to refineries or other suitable processing facilities. Such cooperating independent manipulation of the frequencies, amplitudes, durations, direction, speed and vibratory patterns of vibrational energies generated by the plurality of seismic apparatus enables the controllable creation of multiple cooperating rolling waves of hydrocarbon-containing substances within subterranean reservoirs, and the maneuvering of the rolling waves about the reservoirs so that the hydrocarbon substances are harvested and maneuvered out of pools and lake formations within the reservoir that are separated from wellbores by elevated bottom surface regions of the reservoir, toward and to the wellbores. Furthermore, it is within the scope of this invention to controllably create areas of turbulences and/or vortexes within the mobilized and/or flowing hydrocarbon-containing substances so as to provide: (a) scrubbing of the bottom surface topography of subterranean reservoirs, and/or (b) suctioning of hydrocarbon-containing substances out of pools or crevasses in the bottom surface topography of subterranean reservoirs.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be described in conjunction with reference to the following drawings, in which:
FIG. 1 is a prior art Two-Source Model in computation;
FIG. 2 is a Multi-Source Model of the present invention;
FIG. 3 is a graph showing phase velocity changes vs. frequency with different viscosities;
FIG. 4 is a graph showing phase velocity changes vs. frequency with different permeabilities;
FIGS. 5( a )-( c ) are graphs showing the effects of frequency modulations on the maximum non-dimensional relative displacement changes vs. location of the concerned points;
FIG. 6 is a graph showing comparisons of maximum non-dimensional relative displacement changes vs. location of the concerned point;
FIGS. 7( a ) and ( b ) are graphs showing maximum relative displacements vs. frequency of the right source;
FIGS. 8( a ) and ( b ) are graphs showing maximum relative displacements vs. location of the right source with respect to the location of the left source;
FIG. 9 is a graph showing the maximum relative displacements along the connected line;
FIG. 10 is a graph showing the maximum relative displacements at a specified time;
FIG. 11 as a graph showing the relative displacements in a time span;
FIG. 12 is a graph showing the maximum relative displacements vs. frequency of the right source;
FIG. 13 is a graph showing maximum relative displacements vs. location of the right source with respect to the location of the left source;
FIG. 14 is a graph showing maximum relative displacements of the points along the line perpendicular and passing through the midpoint of the line connecting the two sources;
FIG. 15 is a graph showing the maximum relative displacement field excited by the two sources; and
FIG. 16 is a schematic illustration of an exemplary system according an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
1. Expressions of wave equations in polar coordinate system
Determination of the relative displacements between the solid and fluid of a fluid saturated porous medium is a key aspect of the present invention. To analyze the relative displacements, focus is given to a specific geometric point in the porous medium considered for its relative displacement between the fluid and solid, and the combined effects of the waves of different energy sources on the displacements of the solid and fluid. A 2D model is developed to simulate the real field, and it is convenient for the governing equations and corresponding solutions to be expressed in isotropic polar coordinates. In isotropic polar coordinates, the operators, ∇ and ∇ 2 are given as:
{
∇
=
(
∂
∂
r
+
1
r
)
r
->
∇
2
=
(
∂
2
∂
r
2
+
1
r
∂
∂
r
)
(
13
a
,
b
)
Substitute Eq. (13) into Eq. (9), the equations for dilatational waves can be written as:
{
(
ⅆ
2
ⅆ
r
2
+
1
r
ⅆ
ⅆ
r
)
(
σ
11
u
+
σ
12
U
)
=
1
V
c
2
∂
2
∂
t
2
(
γ
11
u
+
γ
12
U
)
+
b
H
∂
∂
t
(
u
-
U
)
(
ⅆ
2
ⅆ
r
2
+
1
r
ⅆ
ⅆ
r
)
(
σ
12
u
+
σ
22
U
)
=
1
V
c
2
∂
2
∂
t
2
(
γ
12
u
+
γ
22
U
)
-
b
H
∂
∂
t
(
u
-
U
)
(
14
a
,
b
)
For the sake of convenience of derivation process, the following parameters are used as introduced by Biot (1956a),
V c 2 = H / ρ ( 15 ) { σ 11 = P H , σ 12 = Q H , σ 22 = R H γ 11 = ρ 11 ρ , γ 12 = ρ 12 ρ , γ 22 = ρ 22 ρ ( 16 )
in which
H=P+R+ 2 Q, ρ=ρ 11 +ρ 22 +2ρ 12 (17)
According to Sommerfeld Radiation Condition (Pao and Mow., 1973, Diffraction of Elastic Waves and Dynamic Stress Concentration, Crane-Russak Inc., New York), the wave propagating from a cylindrical source can be assumed as:
{ u = C 1 H 0 ( 1 ) ( lr ) exp ( - i ω t ) U = C 2 H 0 ( 1 ) ( lr ) exp ( - i ω t ) ( 18 a , b )
C 1 and C 2 are the displacement amplitudes of solid and fluid, respectively; l is wave number; r is the distance from the considered point to the source. H 0 (1) (•) is the zero-order Hankel function of the first kind. The subscript ‘0’ represents zero order, in the following equations these subscripts have the same meaning; the superscript ‘(1)’ means the function is the first kind. exp(−iωt) is the time factor of the harmonic wave; i=√{square root over (−1)} is the complex unit; ω is the frequency of wave. It should be noted that the wave expression is now in the form of displacement of the fluid and solid in comparing with the volume strain given by Biot (1956a).
Employing the following basic equations (Andrews et al., 2001, Special Functions, Cambridge University Press, Cambridge):
{ ⅆ ⅆ x H 0 ( 1 ) ( x ) = - H 1 ( 1 ) ( x ) ⅆ ⅆ x H 1 ( 1 ) ( x ) = 1 2 [ H 0 ( 1 ) ( x ) - H 2 ( 1 ) ( x ) ] ( 19 a , b )
one may obtain
{ ∂ 2 ∂ r 2 H 0 ( 1 ) ( lr ) = - l 2 2 [ H 0 ( 1 ) ( lr ) - H 2 ( 1 ) ( lr ) ] 1 r ∂ ∂ r H 0 ( 1 ) ( lr ) = - l 2 2 [ H 0 ( 1 ) ( lr ) + H 2 ( 1 ) ( lr ) ] ( 20 a , b )
which may also be expressed in the following form:
∇
2
H
0
(
1
)
(
lr
)
=
(
∂
2
∂
r
2
+
1
r
∂
∂
r
)
H
0
(
1
)
(
lr
)
=
-
l
2
H
0
(
1
)
(
lr
)
(
21
)
By substituting expressions of Eq. (18) into Eq. (14), the following equations can be obtained:
{
-
l
2
(
σ
11
C
1
+
σ
12
C
2
)
=
-
1
V
c
2
ω
2
(
γ
11
C
1
+
γ
12
C
2
)
-
i
ω
b
H
∂
∂
t
(
C
1
-
C
2
)
-
l
2
(
σ
12
C
1
+
σ
22
C
2
)
=
-
1
V
c
2
ω
2
(
γ
12
C
1
+
γ
22
C
2
)
+
i
ω
b
H
∂
∂
t
(
C
1
-
C
2
)
(
22
a
,
b
)
The general equation of velocities for these waves can be expressed as:
V=ω/l, (23)
For the sake of simplification, introduce a parameter:
ξ= V c 2 /V 2 (24)
therefore, Eq. (22) can be rewritten as:
{
ξ
(
σ
11
C
1
+
σ
12
C
2
)
=
γ
11
C
1
+
γ
12
C
2
+
ibV
c
2
H
ω
∂
∂
t
(
C
1
-
C
2
)
ξ
(
σ
12
C
1
+
σ
22
C
2
)
=
γ
12
C
1
+
γ
22
C
2
-
ibV
c
2
H
ω
∂
∂
t
(
C
1
-
C
2
)
(
25
a
,
b
)
Substitution of Eq. (18) into Eq. (1) and elimination of the constants C 1 and C 2 yield the relation:
(
PR
-
Q
2
)
l
4
ω
4
-
(
P
ρ
11
+
P
ρ
22
-
2
Q
ρ
12
)
l
2
ω
2
+
ρ
11
ρ
22
-
ρ
12
2
+
ib
ω
[
(
P
+
R
+
2
Q
)
l
2
ω
2
-
ρ
]
=
0
(
26
)
With the variables already introduced, substitution of Eq. (18) into Eq. (25) and elimination of the constants C 1 and C 2 yield a non-dimensional equation with one single variable ζ:
(
σ
11
σ
12
-
σ
12
2
)
ζ
2
-
(
σ
11
γ
12
+
σ
22
γ
11
-
2
σ
12
γ
12
)
ζ
+
(
γ
11
γ
22
-
γ
12
2
)
+
ib
ωρ
(
ζ
-
1
)
=
0
(
27
)
with
ζ
=
l
2
ω
2
V
c
2
(
28
)
In this case l and ζ are complex variables. V c =H/ρ is the reference velocity. Denoting and ζ I and ζ II are the roots of Eq. (27), which correspond to the velocities of the purely elastic waves as given by Eq. (1), and assume that ζ I is the root which corresponds to the first compression wave, while ζ II is that corresponds to the second wave. ζ I and ζ II have the following expressions:
(ζ I ) 1/2 =R I +iT I (29)
(ζ II ) 1/2 =R II +iT II
The phase velocities of the compression waves can be given by equations:
ν I /V c =1 /|R I | (30)
ν II /V c =1 /|R II | (31)
By solving the quadratic equations of Eq. (27) related to the velocities, two complex roots can be obtained; the image parts reflect the attenuation; while the real parts designate the propagation velocities of the waves. It should be noted that this velocities is the phase speeds, and not the speed of the particle vibration. The ratio of the image part to the real part is important since it describes the degree of damping of the wave.
2. Multi-Source Model Development
The prior art concentrates on studies where there is merely a single source in the consideration domain, i.e. no wave superposition is studied. However, in most common practice, whether the energy from one source is not strong enough, or the desired purpose cannot be obtained by putting just one source in the considered domain, several energy sources can be put in the domain in the real world. Thus, it is more significant and practically meaningful to study the dynamic response of porous media and the relative displacement between solid and fluid when the domain is excited by multiple energy sources. From each of the energy sources, a cylindrical wave is generated and will propagate in the porous medium. Therefore, a model with multiple sources provides a more accurate analysis of superposition wave field. A newly developed moving coordinate method can be employed in building such model and describing the displacement field excited by multiple waves.
As a starting point, it is supposed there are cylindrical compressible waves generated by multiple cylindrical sources, as shown in FIG. 1 . The waves are assumed to be continuous and harmonic, and the waves are in steady state. Moreover, all the waves can be expressed in their own local coordinates with the origins locating at the sources. Under these conditions, the wave from each of the multi-energy sources can be expressed in local coordinates. As shown in FIG. 1 , if the global coordinates are located at one source, then, the coordinates of other source locations can be expressed by d j =r j0 (cos θ j0 +i sin θ j0 ). All the energy sources considered in the present invention disclosed herein are supposed to be continuous and harmonic cylindrical waves generated by multiple cylindrical sources. Furthermore, only steady state is considered. The waves can therefore have the following expressions if they are expressed in their own local coordinates with the origins locating at the sources:
{ u r = u 0 Re [ H 0 ( 1 ) ( lr ) exp ( - i ω t ) ] ( cos θ + i sin θ ) U r = U 0 Re [ H 0 ( 1 ) ( lr ) exp ( - i ω t ) ] ( cos θ + i sin θ ) ( 32 )
in which, the term (cos θ+i sin θ) is introduced to represent the direction of the displacement vector. Consequently, this term can be replaced by [z/|z|]. z has the expression, z=x+iy, with x=r cos θ and y=r sin θ in the polar coordinate system.
Thus, the waves propagating from each of the sources can be expressed by the following formulas:
{
u
r
1
=
u
01
Re
[
H
0
(
1
)
(
l
1
r
1
)
exp
(
-
i
ω
1
t
)
]
[
z
1
z
1
]
U
r
1
=
U
01
Re
[
H
0
(
1
)
(
l
1
r
1
)
exp
(
-
i
ω
1
t
)
]
[
z
1
z
1
]
(
Wave
One
)
and
(
cos
θ
+
i
sin
θ
)
(
33
a
,
b
)
{
u
r
2
=
u
02
Re
[
H
0
(
1
)
(
l
2
r
2
)
exp
(
-
i
ω
2
t
)
]
[
z
2
z
2
]
U
r
2
=
U
02
Re
[
H
0
(
1
)
(
l
2
r
2
)
exp
(
-
i
ω
2
t
)
]
[
z
2
z
2
]
(
Wave
Two
)
…
(
34
a
,
b
)
{
u
r
n
=
u
0
n
Re
[
H
0
(
1
)
(
l
n
r
n
)
exp
(
-
i
ω
n
t
)
]
[
z
n
z
n
]
U
r
n
=
U
0
n
Re
[
H
0
(
1
)
(
l
n
r
n
)
exp
(
-
i
ω
n
t
)
]
[
z
n
z
n
]
(
Wave
n
)
(
35
a
,
b
)
Here, u 0j and U 0j (j=1, 2, . . . , n) are respectively the displacement amplitudes of the solid and fluid of the j th source. u 0j and U 0j (j=1, 2, . . . , n) are respectively the displacement vectors of solid and fluid excited by the j th source. z j =x j +iy i , is a complex variable, and r j =|z j |, is the distance from a point P to the j th wave sources; the term [z j /|z j |] is introduced to describe the direction of the displacements.
In order to investigate the superposed action of multiple waves conveniently, the expression for each wave is to be written in a common coordinate system by using the moving-coordinate method (Wang, 2002, J. Earthquake Eng. Eng. Vibr., 1: 36-44).
Expressing wave j in the xoy-coordinates as shown in FIG. 1 , z j =z−d j :
{ u r j = u 0 j Re [ H 0 ( 1 ) ( l j r j ) exp ( - i ω j t ) ] [ z j z j ] = u 0 j Re [ H 0 ( 1 ) ( l j z - d j ) exp ( - i ω j t ) ] [ z - d j z - d j ] U r j = U 0 j Re [ H 0 ( 1 ) ( l j r j ) exp ( - i ω j t ) ] [ z j z j ] = U 0 j Re [ H 0 ( 1 ) ( l j z - d j ) exp ( - i ω j t ) ] [ z - d j z - d j ] ( 36 a , b )
d j are the coordinates of the j th wave source in the common coordinates.
With the equations developed, the total displacements of any given point, P, in the domain considered can be described in a common coordinate system. xoy-coordinates can be considered as the common coordinates (also named global coordinates). This implies that d 1 =0. The combined displacements can now be presented by:
{
u
r
=
∑
j
=
1
n
u
rj
=
u
01
Re
[
H
0
(
1
)
(
l
1
z
1
)
exp
(
-
i
ω
1
t
)
]
[
z
1
z
1
]
+
⋯
+
u
0
n
Re
[
H
0
(
1
)
(
l
n
z
-
d
n
)
exp
(
-
i
ω
n
t
)
]
[
z
-
d
n
z
-
d
n
]
U
r
=
∑
j
=
1
n
U
rj
=
U
01
Re
[
H
0
(
1
)
(
l
1
z
1
)
exp
(
-
i
ω
1
t
)
]
[
z
1
z
1
]
+
⋯
+
U
0
n
Re
[
H
0
(
1
)
(
l
n
z
-
d
n
)
exp
(
-
i
ω
n
t
)
]
[
z
-
d
n
z
-
d
n
]
(
37
a
,
b
)
The displacement wave field excited by multiple cylindrical sources can be quantified by using the model provided above. The characteristics of the wave field can be analyzed quantitatively when the parameters of material and the sources or the locations of the sources are specified.
3. Numerical Simulation
To demonstrate the application of the model established, numerical simulations are performed as the basis of the wave model and the solutions developed. A numerical simulation for the wave generated by two energy sources is shown in FIG. 2 . The distance between the two sources is noted as d, the position of point P in the field is expressed as: z=x+iy, the frequencies of the two source waves are ω 1 and ω 2 respectively. For the sake of simplification, it is assumed that the solid skeleton system is formed by spherical solid particles as the assumption made by the other researches conventionally. The particles' compressibility can be neglect. The parameters A, P, Q, and R in Eq. (1) have the following forms (Lin et al., 2001):
A = 2 v s 1 - 2 v s μ s + ( 1 - ϕ ) 2 ϕ K f ( 38 ) P = A + 2 μ s ( 39 ) Q = ( 1 - ϕ ) K f ( 40 ) R = ϕ K f ( 41 )
where μ s is the shear modulus of the material; ν s is the Poisson ratio of the solid.
Once the physical parameters are given, the coefficient values of waves can be determined by the wave model established. Table 1 gives the parameter values used in the numerical computation. Table 2 shows the values of wave velocities and amplitudes and their ratios calculated.
TABLE 1
The values of parameters of the porous medium
Φ
μ
ν s
μ s
K f
ρ s
ρ f
μ s /K f
0.246
5 cp
0.29
10.0 GPa
2.4 GPa
2700
1000 kg/m 3
4.17
kg/m 3
TABLE 2
The values of parameters of the waves
Attenuation
Attenuation
V fast /
C 1 /
Frequency
V fast
V slow
ratio I
ratio II
V slow
C 2 *
5 Hz
4400
114 m/s
0.0053
0.7214
38.47
1.258
m/s
*C1/C2: The ratio of amplitudes of solid to fluid.
The phase velocity of the wave and the relative displacements of a random point P in the wave field are computed. The comparison between the results with the consideration of fluid viscosity and result without the concern of viscosity of the fluid is also performed. FIG. 3 and FIG. 4 show the phase velocity changes versus the frequency of the wave in a porous medium. One can see from these figures that with the increase of frequency, the velocity of wave will rise. In the low frequency region, the velocity increases more quickly than in the high frequency region. Also from FIG. 3 , for the same frequency, the larger of the viscosity of the fluid the larger of the velocity; and from FIG. 4 , the higher of the permeability of the porous medium, the larger of the velocity.
FIG. 5 shows the non-dimensional relative displacement amplitudes along the line connecting the two sources. The non-dimensional relative displacement used in FIG. 5 is defined by (U−u)/u. The locations of the two sources are at x=0, y=0 and x=1600 m, y=0 respectively. It should be noted that, for each of the waves, the amplitudes of the wave decrease in general with the increasing distance from the energy source. Moreover, the amplitude of the combined wave at steady state is not simply the summation of the amplitudes of the two waves. As can be seen from FIG. 5 , when the porous medium is excited by two energy sources, the wave response (maximum amplitudes of the displacements) is totally different from that of the single source (represented by the curves of “left effect” and “right effect” respectively). For some areas, the amplitude of the combined wave is smaller than that of single source, while for some other areas the amplitude is larger than that of the single source. One may also find from the figure that the amplitude of the wave can be zero at a certain location between the two sources. It is also noted that the frequency of the resulting wave generated by the two energy sources are varied from the frequencies of the two energy sources.
The comparison between the results from two cases with and without the consideration of the fluid viscosity is illustrated in FIG. 6 . One can find the effect of viscosity of on the relative displacement is very slight, and can be neglected.
Effect of the source frequencies on the wave propagation is shown in FIG. 7 , in which the relative displacement of the middle point of the connecting line between the two sources is plotted with respect to the change of the frequency of the right energy source. The selected point in FIG. 7 is located at the middle of the line, x=800 m, y=0 with unit of meter, while the distance between the two sources is 1,600 meters. As illustrated in FIG. 7 , the non-dimensional relative displacement of the point becomes relatively stable with the increase of the frequency of the second source. At the steady state, the relative displacement varies periodically as shown in the figure. Quantitatively, the maximum relative displacement of this point can be twice as that of the single source, whereas the minimum relative displacement is almost zero.
Effects of distance between the two sources on the wave motion of the porous medium are also evaluated in the present invention. FIG. 8 shows the relative displacement of a point at x=200 m, y=0, with respect to the excitations of the left source with a constant distance from the point and the right source with a varying distance from the point. As exhibited in the figures that the effect of the right source decreases as the distance between the concerned point and the right source increases. It may also be observed from the figure that the peak value of the relative displacement varies periodically with the increase of the distance between the right source and the point considered.
As described previously, the relative displacements can be quantified at any specified time for any given point in the considered domain by using the methodology of the present invention disclosed herein. The relative displacements of the porous medium along the line connecting the two resources also form a wave at any specified time, as shown in FIG. 10 for a case calculated. One sees that the combined effect can be smaller as well as larger than the effect just by one source.
For any selected point in the domain, the relative displacement history of the point can be determined with the solutions derived. FIG. 11 shows an example of the calculation. The selected point in FIG. 5 is located at x=750, y=0 with unit of meter, while the distance between the two sources is 1,500 meters. For this specific case, as can be seen from the figure, the resulting wave generated by the two sources with identical frequency appears as a periodic motion. But the frequency of the superposed wave is different from these of the two source waves.
Effect of the source frequencies on the wave propagation is shown in FIG. 12 in which the relative displacement of the middle point of the connecting line between the two sources is plotted with respect to the change of the frequency of the right energy source. The distance between the two sources is 1,500 m. As illustrated in FIG. 12 , the non-dimensional relative displacement of the point becomes relatively stable with the increase of the frequency of the second source. It should be noted that the frequencies and amplitudes of the two sources are not changing with time once they are specified. As the relative displacement becomes stable, the magnitude of the relative displacement appears as varying periodically as shown in the figure. Quantitatively, the maximum relative displacement of this point can be twice as that of the single source, whereas the minimum relative displacement is almost zero.
Effects of distance between the two sources on the wave motion of the porous medium are also evaluated in the present invention. FIG. 13 shows the relative displacement of a point at x=200, y=0, with respect to the excitations of the left source with a constant distance from the point and the right source with a varying distance from the point. As exhibited in the figures that the effect of the right source decreases as the distance between the concerned point and the right source increases. It may also be observed from the figure that the peak value of the relative displacement varies periodically with the increase of the distance between the right source and the point considered.
It should be noted that the equations disclosed herein can be used to calculate for the motion of a randomly selected particle of the porous medium considered. This implies that the three-dimensional displacement field of the porous medium subjected to multi-energy sources can be numerically determined with the equations at any specified time. The wave propagations and superposed action in the porous medium consisting fluid and solid can therefore be quantified. FIG. 14 shows the relative displacements of the points along the perpendicular bisector of the line joining the sources, corresponding to the various frequencies of the sources.
of the line connecting the two sources
FIG. 15 illustrates a 3D wave shape of the relative displacement field of a 2D plane. The frequencies of the two sources are ω 1 =5, ω 2 =50 respectively; one wave locates at x=0, y=0, while the other one locates at x=1500, y=0. The vertical axis of the figures is the maximum values of the non-dimensional relative displacement with respect to different source frequencies.
4. Conclusions
The invention disclosed herein provides methods, apparatus and systems for stimulating wave motion and vibrations of the fluid and solid in a fluid-saturated elastic porous medium. The present invention provides means for affecting the mobility and fluidity of hydrocarbon-containing substances within subterranean reservoirs, and for manipulating the maneuverability of the flows of mobilized hydrocarbon-containing substances within and about subterranean reservoirs. The stimulation model with wave equations disclosed herein provides simulations, analyses and characterization of the vibrational displacements of solids and fluids respectively. The wave expressions propagating from the cylindrical sources are constructed in polar coordinate system with the utilization of Hankel function. This makes the availability of the evaluation of the dynamic response of the porous medium subjected to the excitations of multi-energy sources. Solutions of the model are developed with the employment of a moving-coordinate method. By making use of the model disclosed herein, the behavior of any specified point in the considered domain of the porous medium can be quantified, and the relative displacement between the fluid and solid of the medium can be conveniently determined. The wave field of the considered porous medium is thus determined for any given time and the analysis of the wave motions in the medium is then readily available. Various mechanical and physical parameters of the porous medium are taken into consideration in developing the governing equations of waves, thus the model established can be applied to different porous media as desired. The numerical simulations of this invention show the efficiency of applying the model established in quantifying the effects of the waves generated by different energy sources on the motions of the fluid and solid of a porous medium. The numerical computations demonstrate that the frequencies and amplitudes of the superposed waves can be controlled and modulated as desired by changing the frequencies, amplitudes and locations of the multiple energy sources. Those skilled in these arts will understand that although only one point is considered in the numerical calculations disclosed herein, the wave motions of all the particles in a selected domain can be conveniently determined and plotted by the formulas, and methods for their use as disclosed herein.
Those skilled in these arts will understand that the invention disclosed herein provides an understanding of how to apply mechanisms of seismic vibration for Enhanced Oil Recovery (EOR) from subterranean reservoirs by the use of vibrating seismic waves to increase the mobility of fluid materials in porous media such as subterranean geological formations encompassing subterranean voids. Hydrocarbon-containing substances, e.g., crude oil, contained within and about subterranean reservoirs comprising rock strata, are commonly intermixed with natural and/or introduced sources water. Significant quantities of naturally occurring crude oil are typically adhered to the rock strata by cohesive and adhesive bonding between the solid strata and the crude oil fluids. Seismic excitation generally increases the pore pressures within the rock strata thereby stimulating and promoting the mobility of molecules comprising fluid materials, e.g., hydrocarbon-containing substances contained within and about subterranean geological formations. Residual fluid hydrocarbon-containing substances in subterranean reservoirs, naturally occurring or introduced sources of water and geological strata have different physical densities and consequently, when vibrational seismic energy is delivered to a subterranean target comprising hydrocarbon-containing substances, water and rock strata, each of these components will respond in different ranges, intensities and duration of physical movements which can be defined by terms relative motion and relative displacements. The hydrocarbon-containing substances, as exemplified by crude oil, tend to vibrate differently from the rock strata in response to seismic excitation, i.e., the crude oil is mobilized by seismic excitation. The rapid vibration of crude oil in response to excitation by seismic vibrational energy enables the controllable movement of the mobilized oil in an energy-directed wave pattern. Continued seismic excitation over an extended time period results in reduction of the capillary forces adhering the crude oil to the rock strata pores thereby enabling the mobilized crude oil to cluster into a continuous fluidized stream. Furthermore, the contact angle between the rock formations and the fluids can be changed due to the wave motions being propagated in the porous media such that the hydraulic coefficient of friction is changed. All of these factors can increase the mobility of crude oil within subterranean reservoirs thereby enabling increases in the recovery of crude oil from subterranean reservoirs. However, it should be understood that a key aspect of the present invention is that the seismic wave motions must be “properly” applied on subterranean reservoirs. The “proper” vibration or desired motion at the selected point in the porous media considered requires appropriate amplitude, frequency, duration and direction of motion, under the excitation of artificial seismic waves.
The numerical modeling approach and related formulae and algorithms disclosed herein can be incorporated into computer software configured to communicate and cooperate with seismic apparatus, electronic seismic control devices and geophysico-chemical sensing apparatus to determine and generate such “proper” vibrational seismic energies directed at subterranean targets for selected durations of time, to controllably modulate the frequencies and amplitudes of the seismic energies, and to controllably redirect the seismic energies to different subterranean targets. The numerical modeling approach, formulae and algorithms of the present invention are manipulable to provide the “proper” seismic vibrations with a variety of different types of seismic apparatus, and with a plurality of said seismic apparatus, with a variety of electronic seismic control devices. Furthermore, the numerical modeling approach, formulae and algorithms of the present invention are manipulable with software programs configured for these purposes to provide means by which the individual wave frequencies and amplitudes of a plurality of vibrational seismic energies generated and emitted by a plurality of seismic apparatus, can be individually modulated to provide optimal mobilization and flow of crude oil within subterranean environments. Furthermore, it is within the scope of this invention to manipulate the numerical modeling approach, formulae and algorithms disclosed herein to superpose and correlatively generate vibrational seismic energies from a plurality of seismic apparatus directed at common subterranean targets.
The methods, apparatus, systems, numerical modeling approach and related formulae and algorithms disclosed herein enable energy-efficient generation of “proper” seismic vibrational waves. Prior art uses of vibrational energies for enhanced oil recovery are based on the waves generated by a single energy source or vertically aligned multiple energy sources. The energy thus produced is attenuated as the waves propagate away from the energy source. The methods and systems of the present invention disclosed herein, however, enable the generation of combinations of multiple waves propagating from multiple seismic energy sources toward a common target zone. An exemplary system 30 is shown in FIG. 16 positioned at ground level 10 above a subterranean reservoir 20 . The system 30 comprises three seismic apparatus 32 , 35 , 38 which are positioned triangulated above the subterranean reservoir 20 . The three seismic apparatus communicate with an electronic seismic control device 40 . The electronic seismic control device 40 with a sensing apparatus 50 that is configured to detect, analyze, characterize and report fluidity and patterns of flow of hydrocarbon-containing materials within the subterranean reservoir 20 . The electronic seismic control device 40 is configured to concurrently and controllably modulate the emission of vibrational energies 33 , 36 39 from seismic apparatus 32 , 35 , 38 , respectively. Furthermore, it is possible with the scope of the present invention to create and effect desired vibration amplitudes by synchronously and/or asynchronously combining energies accumulated by pluralities of overlapping, communicating and cooperating seismic waves that are continuously being emitted toward a common target from the multiple seismic energy sources. In other words, vibrational resonances can be controllably generated by overlapping, intersecting and combining the seismic vibrational energies emitted from the multiple sources. Since seismic waves are elastic waves, the vibrational resonances created by combining multiple seismic waves can be significantly large relative to the seismic energy emitted from a single source. Furthermore, it is within the scope of this invention to controllably manipulate the intersecting and/or overlapping and/or combining of multiple seismic vibrational energies to controllably create, modulate and manipulate cooperating reciprocating and/or vortexing and/or rolling motions of the targeted subterranean hydrocarbon-containing substances such as crude oil. Accordingly, the present invention is suitable for use during harvesting and recovery of crude oil from: (a) newly developed subterranean reservoirs, i.e. with new installations of wellbores into newly accessed subterranean reservoirs (for example, by reducing the numbers of wellbores required for conventional recovery of crude oil from such reservoirs), (b) low-producing subterranean reservoirs affected by the density of the crude oil contained therein, (c) depleted or “shut-in” wells wherein residual crude oil that was not accessible with conventional oil recovery methods and apparatus, remains in subterranean pools or crevasses, and (d) depleted reservoirs that were water-flooded during initial crude oil recovery containing therein crude oil droplet form suspended in pumped water remaining in such reservoirs.
While this invention has been described with respect to the preferred embodiments, it is to be understood that various alterations and modifications can be made to methods, apparatus and systems for manipulating the viscosities and flows of hydrocarbon-containing substances within subterranean reservoirs within the scope of this invention whereby which are limited only by the scope of the appended claims. | Methods, apparatus and systems for controllably mobilizing, flowing and maneuvering the flow of hydrocarbon-containing materials within and about a subterranean reservoir. The system comprises selectively positioning at a ground surface level above a subterranean reservoir containing hydrocarbon-containing materials, at least three seismic apparatus spaced apart in a triangulated configuration. The system is provided with an electronic seismic control device configured to controllably communicate with and cooperate with each of the seismic apparatus to concurrently modulate the amplitudes and frequencies of the vibrational energies produced therefrom. The system is provided with a sensing apparatus configured to detect and monitor changes in the fluidity and movement of the hydrocarbon-containing materials about the subterranean reservoir. The electronic seismic control device is controllably manipulated to precisely modulate the frequencies and amplitudes of the seismic vibrational energies emitted by each of the seismic apparatus to controllably maneuver the flow of the fluidized hydrocarbon-containing materials about the subterranean reservoir. | 4 |
FIELD OF THE INVENTION
This invention relates to high pressure fluid intensifier systems. More particularly, this invention relates to check valve assemblies for controlling fluid flow into and out of the high pressure intensifier chamber.
BACKGROUND OF THE INVENTION
In a typical high pressure fluid intensifier system, hydraulic fluid acts on a reciprocating double-acting, low pressure--high pressure piston assembly to compress water to several thousand psi. The piston assemblies of such systems are exposed to hydraulic fluid pressures on the order of 2,000 psi and to outlet water pressures on the order of 20-60,000 psi. These assemblies must be designed to withstand tremendous pressure fluctuations while at the same time maintain hydraulic fluid/water separation.
The inlet and outlet valve members of the pressurized fluid check valve assembly and their valve seats are severely stressed and corroded. Replacement of the valve members and their seats periodically is difficult because of the attachment of the various members making up the intensifier pressure chambers and piston assembly. Usually, the intensifier must be completely dismantled to reach and repair or replace such internal elements.
SUMMARY OF THE INVENTION
The check valve assembly of the invention is designed to be accessible for service without dismantling the intensifier appurtenant thereto. The high pressure water outlet portion is provided at the outer end of the assembly and is accessible by simply removing a high pressure fluid outlet adapter. Removal of the adapter exposes the high pressure valve element and its seat for service or replacement.
The inner, low pressure end of the assembly requires service less often. To access the low pressure end, the valve assembly must be removed from the intensifier. To facilitate the removal of the check valve assembly, the assembly is designed to be secured to the intensifier by an end retainer ring that positions the assembly in fluid communication with the intensifier high pressure chamber. By removal of the retainer ring, the check valve assembly can be removed without dismantling the the intensifier.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevation of the right half of the intensifier of this invention in partial cross section; and
FIG. 2 is an enlarged cross section of the inlet/outlet valve shown in FIG. 1 with the high pressure outlet depicted in an open condition; and
FIG. 3 is similar to FIG. 2 with the high pressure outlet depicted in a closed condition;
DESCRIPTION OF THE INVENTION
An intensifier arrangement utilizes hydraulic fluid (oil) to drive a high pressure--low pressure piston assembly to produce a high pressure water flow. The intensifier shown in FIG. 1 is double-acting. It comprises a housing 10 in the form of an elongated steel cylinder. One half, the right half, is shown in FIG. 1. The left half is a duplicate. Each end of the housing mounts an end retainer ring12, the end of housing 10 being internally threaded to mate with external threads on end retainer ring 12 as shown. Within housing 10, a low pressure chamber 14 is provided by a steel cylinder 16 fitted onto a cylindrical end cap 18 at each end (the right hand cap being shown; the left hand end cap is an opposite hand duplicate). Also within housing 10, a left hand and a right hand high pressure chamber are provided (the right hand high pressure chamber 20 being shown; the left hand high pressure chamber is a duplicate), each by an elongated steel barrel cylinder 22 fitted at its inner end into end cap 18 and at its outer end onto a valve body 24 of an inlet/outlet water check valve assembly. End retainer 12, acting through valve body 24, centers the outer end of cylinder 22.
The outer surface of end cap 18 conforms to the inner surface of housing cylinder 10, with a small allowance for a slip-fit clearance. Tightening the end retainers 12 places the pressure chamber elements in longitudinal compression and the housing cylinder 10 in longitudinal tension. When one or both end retainers 12 are removed, however, these elements may be removed from the housing in a very expeditious manner. The low pressure and high pressure cylinders, 16 and 22, are mounted in axial alignment with the housing cylinder 10 by the end caps 18 and the retainer rings 12. Because of the relative dimensions of the elements thus far described, the pressure chamber elements are confined against any lateral or longitudinal movement.
The low pressure--high pressure piston assembly comprises a low pressure piston 26 and left and right hand high pressure pistons 28 and 30. The low pressure piston is a cylindrical disk contained within low pressure chamber 14. Its outer surface conforms to the inner surface of low pressure cylinder 16, with a small allowance for a slip-fit clearance, and mounts appropriate hydraulic pressure seals 32 to seal one side of low pressure chamber 14 from the other. The high pressure pistons are connected to opposite faces of the low pressure piston 26 and extended through the respective cylinder block 18 into high pressure chamber sleeve 20.
The outer end of high pressure cylinder 22 fits over a pilot or shoulder that protrudes from the check valve body 24. Valve body 24 is machined to provide a cylindrical pilot 24a for that purpose. The end of the pilot is machined to provide a smaller cylindrical end surface as a seat for a high pressure static seal group 44. The stepped transition between the high pressure cylinder-mounting pilot and the high pressure seal seat provides a metal back up for seal group 44. The end diameter of pilot 24a corresponds to the diameter of high pressure piston rod 30 as shown.
As high pressure piston rod 30 is retracted from the position shown, low pressure water is drawn into high pressure chamber 20 through inlet passage 50 in inlet/outlet water check valve assembly 25. When piston rod 30 is driven back to the position shown, water is compressed to a high pressure and then forced out through outlet passage 54 in check valve assembly 25. Water flow into and out of high pressure chamber 20 is controlled by a water pressure-influenced poppet-type check valve mechanism 52.
Inlet/outlet water check valve assembly 25 comprises valve body 24, low pressure water inlet manifold 51 communicating with low pressure water inlet passage 50, poppet check valve mechanism 52, high pressure outlet water line adapter 53 communicating with high pressure water outlet passage 54, and manifold lock nut 55 receiving manifold 51 to valve body 24. The outer end of valve body 24 is externally threaded and lock nut 55 screwed thereon to position manifold 51. Low pressure inlet water line 56 is attached to manifold 51 and high pressure outlet water line 57 is attached to adapter 53. The inner face of manifold 51 is machined to provide an annulus 58 for distribution of inlet water from inlet line 56 to inlet passage 50.
the check valve mechanism 52, as shown in enlarged detail in FIGS. 2 and 3, comprises an inlet poppet 100, an outlet poppet 102, a valve stem 104 connecting the two poppets, a high pressure poppet seat 106, and an enlarged abutment end 108 of stem 104 to retain and secure outlet poppet 102. The stem 104 extends through high pressure water outlet passage 54 and mounts the poppets at opposite ends. The inner end or head 110 of stem 104 is machined to provide an inner annular groove 111 for a return coil spring 114 and a spring retainer "E" ring clip 112 for retaining poppet 100. The mechanism is so arranged that inlet poppet 100 seats on the inner end surface of pilot 24a to seal low pressure water inlet passage 50, and outlet poppet 102 seats on high pressure seat element 106 to seal high pressure water outlet 54. Inlet poppet 100 is slidably mounted by and is axially moveable on the inner end of stem 104. Outlet poppet 102 is slidably mounted by and is axially movable on the outer end of stem 102 and retained thereon by enlarged stem end 108. The length of stem 104 between head 110 and the end 108 is sufficient to enable outlet poppet 102 to be unseated (as shown in FIG. 2) when high pressure water bears against head 110 and shifts stem 104 as far outward as head 110 permits. Head 110 and the inner end portion of stem 104 are axially counterbored to provide a passage 115 that communicates with one or more diametric passages 116 cross-bored in stem 104. The outer end of stem 104, just inward of outlet poppet 102, is shaped to provide a passage 118 between that portion of stem 104 and the bore through valve body 24 high pressure water outlet passage 54. The intermediate length of stem 104 is shaped to provide a passage 120 between that portion of stem 104 and the bore through valve body 24, which bore provides high pressure water outlet passage 54. Passage 120 interconnects cross-bore 116 and passage 118 to enable high pressure water to pass through water outlet passage 54 when outlet poppet 102 is lifted from its seat 106 to the position shown in FIG. 2. Adapter 53 is provided with an inner cavity 122 that extends from seat element 106 to the high pressure outlet water line 57 and encloses outlet poppet 102 and enlarged stem 108 with space to spare for high pressure water travel around poppet 102 and end 108 from passage 54 to outlet line 57. Adapter 53 has a beveled annular surface 124 at the base of cavity 122. Surface 124 bears against a corresponding beveled surface on seat element 106 to secure seat 106 in a recess 126 provided therefor in the outer end of valve body 24, when adapter 53 is screwed onto valve body 24. Inlet poppet 100 is provided with an annular recess 128 that communicates with inlet water passage 50 when inlet poppet 100 is seated against the end surface 130 of stub 24a. Spring 114 seats in a depression machined in the adjacent face of inlet poppet 100.
When water has been compressed by the high pressure piston rod to a pressure sufficient to overcome the spring force of spring 114, valve stem 105 is shifted to the position shown in FIG. 2 by water pressure acting on valve stem head 110. Prior to that point in time, water pressure acting on inlet poppet 100 would have closed inlet poppet 100 against surface 130 on valve body plug 24a to seal off low pressure inlet water passage 50. With valve stem 104 positioned as shown in FIG. 2, outlet poppet is raised from its seat element 106 and high pressure water is forced by the high pressure piston rod through passages 114, 116, 120 118 into cavity 122 and out through line 57. When the high pressure piston rod reaches the end of its pressurization cycle, reverses, and begins to retract, the spring force of spring 110 and the reverse force of high pressure water in line 57 forces valve stem 104 to the position shown in FIG. 3, seating outlet poppet 102 against seat element 114 to close off the high pressure outlet to line 57. As the high pressure piston rod is retracted, the force of low pressure water from passage 50, acting concentrically within annular recess 128 on inlet poppet, lifts poppet 110 from its seat 130 on pilot 24a and flows around poppet 100 into the high pressure chamber. The spring force of spring 114 is sufficiently small that the force of low pressure water acting on the opposite side of poppet 100 will shift poppet 100 along valve stem 104 from the position shown in FIG. 3 toward valve stem head 110 to release water from passage 50 into the high pressure chamber. The travel length of poppet 100 is limited by spring clip 112.
Of the two poppet sealing surfaces, the sealing surface 132 associated with outlet poppet 102 incurs much more severe stress. Consequently, seat element 124 is provided as a replaceable element. Moreover, the mating surfaces of poppet 102 and seat element 124 undergo wear, necessitating that these surfaces must be periodically polished to avoid high pressure water back leakage from line 57. The configuration and arrangement of adaptor 53 permits convenient handling of these matters. Without dislodging or disassembly of any part of the rest of the system, adaptor 53 can be unscrewed and removed from valve body 24 to expose seat element 106, poppet 102 and enlarged stem end 108. Poppet 102 can be removed to permit polishing of the sealing surfaces, replacement of the seat element 106 or poppet 102, or whatever else may be required in connection with the high pressure outlet check valve mechanism by removing the assembly and disconnecting clip 112. High pressure outlet line 57, typically a stainless steel tubing, is preferably coiled in the vicinity of adapter 53 and screwed thereto by mans of a coupling that permits adapter 53 to be turned relative to line 57. The resiliency of the coiled tubing permits the removal of adapter 53 away from the valve body 24 for working on the exposed mechanism.
While a preferred embodiment of an intensifier check valve assembly, made in accordance with the principles of the present invention, has been described and illustrated, certain changes may be made without departing from the scope of the invention. | A check valve assembly for fluid pressure-intensifying apparatus of the double-acting type is provided. The assembly has an inner low pressure poppet valve member communicable with the high pressure chamber of fluid pressure-intensifying apparatus, and an outer high pressure poppet valve member communicable with a high pressure fluid outlet line. The check valve assembly is designed for service accessibility without having to dismantle the intensifier. | 5 |
This is a continuation of application Ser. No. 07/723,216, filed Jun. 28, 1991, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a non-volatile semiconductor memory suitable for high integration and a method for manufacturing the same.
Referring to a conventional non-volatile semiconductor memory shown in FIG. 6, an N-type drain region 1a and an N-type source region 1b are provided on the surface of a P-type semiconductor substrate 1. A three-layer film 36 is provided apart from the source region 1b through a gate insulating film 2 by a constant distance. The three-layer film 36 includes a floating gate 3, a layer insulation film 33 and a control gate 34. A side wall electrode 35 is formed between the source region 1b and the three-layer film 36.
With the above-mentioned structure, the optimum potentials are applied on the side wall electrode 35 and the control gate 34, respectively. As a result, electrons can be injected from the source side to the floating gate 3.
Referring to the conventional non-volatile semiconductor memory, a side wall is formed between the source region 1b and the three-layer film 36 having the floating gate 3 on a self-control basis and is used as the electrode 35. Consequently, the whole manufacturing steps are very complicated.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a non-volatile semiconductor memory capable of performing electrical writing and erasure which can be manufactured more easily without side wall electrodes on an offset region in a channel region and with a small cell area, and a method for manufacturing the same.
The present invention provides a non-volatile semiconductor memory comprising a semiconductor substrate, drain and source regions which are provided on the surface of the semiconductor substrate and have P or N type differently from the semiconductor substrate, a floating gate (first gate electrode) for covering a portion of a channel region between the drain and source regions, the drain region being self-aligned with the floating gate, the source region being provided apart from the floating gate through an offset region in the channel region by a constant distance, whereby the drain and source regions are asymmetrical to each other with respect to the floating gate, a control gate (second gate electrode) for controlling the surface potential of the whole channel region, and a third gate electrode provided above the control gate through an insulating film for substantially controlling the surface potential on the underside of the floating gate and in the vicinity thereof so that electrical writing and erasure can be performed, wherein the density of the offset region on the semiconductor substrate surface is made different from that of other port:ions on the semiconductor substrate surface so that electrons can be injected from a source, or a non-volatile semiconductor memory comprising a semiconductor substrate, drain and source regions which are provided on the surface of the semiconductor substrate and have P or N type differently from the semiconductor substrate, a floating gate (first gate electrode) for covering a portion of a channel region between the drain and source regions, the drain region being self-aligned with the floating gate, the source region being provided apart from the floating gate through an offset region in the channel region by a constant distance, whereby the; drain and source regions are asymmetrical to each other through the floating gate, and a control gate (second gate electrode) for controlling the surface potential of the whole channel region, wherein the density of the offset region on the semiconductor substrate surface is made different from that of other portions on the semiconductor substrate surface and the density of the offset region is substantially increased so that electrons can be injected from a source.
From another aspect, the present invention provides a method for manufacturing a non-volatile semiconductor memory comprising steps of implanting ions on the whole surface of a semiconductor substrate, on which a floating gate is provided through a gate insulating film, in an approximately perpendicular direction, implanting the ions in an oblique direction to the semiconductor substrate surface, forming a channel region which has an offset region and a semiconductor substrate surface region on the underside of the floating gate, forming a control gate through an insulating film on the whole surface of the semiconductor substrate having the floating gate, laminating an insulating film on the whole surface and flattening the same, and forming a third gate electrode which substantially controls the surface potential on the underside of the floating gate and in the vicinity thereof so that electrical writing and erasure can be performed, or a method for manufacturing a non-volatile semiconductor memory comprising steps of implanting ions on the whole surface of a semiconductor substrate, on which a floating gate is provided through a gate insulating film, in an approximately perpendicular direction, implanting the ions in an oblique direction to the semiconductor substrate surface, forming a channel region which has an offset region and a semiconductor substrate surface region on the underside of the floating gate, forming an insulating film on the whole surface of the semiconductor substrate which has the floating gate such that the floating gate is embedded therein and flattening the same, etching back the insulating film thus flattened so as to expose only the top of the floating gate, and forming a control gate through an insulating film which is newly formed on the whole surface of the semiconductor substrate having the floating gate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1(a)-(f) includes cross-sectional views taken along section line I--I' of the semiconductor memory shown in FIG. 5 for explaining manufacturing steps according to a first embodiment of the present invention;
FIG. 2 is a diagram for explaining a structure according to a second embodiment of the present invention;
FIGS. 3(a)-3(c) is a diagram for explaining steps of manufacturing the same device as that of the second embodiment according to a third embodiment of the present invention;
FIGS. 4 and 5 are diagrams for explaining the structure of main portions of different cell layout examples according to the present invention, respectively;
FIG. 6 is a diagram for explaining the structure of a main portion according to a prior art; and
FIG. 7 is a cross-sectional view of the semiconductor memory shown in FIG. 5 along section line VII--VII' according to the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In a channel region formed between source and drain regions, the surface density of an offset region is made higher than the density of a semiconductor substrate surface region which is provided just below a floating gate, and/or the thickness of an insulating film, which is formed just above the offset region, is made higher. Consequently, the voltage characteristics to be applied to a control gate can be enhanced when injecting electrons (writing data) from the source region (when programming) (a voltage is set equal or greater than a threshold voltage Vth of the offset region). As a result, if the surface density of the offset region is increased, the coupling capacitance through the control gate can effectively cause the potential of the floating gate to be increased so as to obtain the potential necessary for injecting the electrons from the source region (about one and a half times to twice as much as a drain voltage). Consequently, a shortage, which is made smaller than a conventional one, of the floating gate potential necessary for injecting the electrons from the source region can be supplied by the coupling capacitance through the control gate from a third gate electrode. As a result, there can be obtained the cumulative floating gate potential necessary for injection. Thus, the electrons can easily be injected from the source region.
According to other embodiments of the present invention, the threshold voltage Vth of the offset region is increased to be equal to a control gate potential such that the floating gate potential necessary for injection can be obtained. Consequently, the electrons can be injected from a source without the third gate electrode.
Furthermore, the shortage of the floating gate potential increased by the coupling capacitance through the control gate can be supplied by direct coupling capacitance of the floating gate with the third gate electrode provided on the same surface as the floating gate. However, a cell size is increased.
Preferred embodiments of the present invention will be described in more detail with reference to the drawings.
FIG. 1(f), which is a cross-sectional view of the semiconductor non-volatile memory along section line I--I' of FIG. 5, shows regions 6 and 7 on the surface of a P-type Si substrate 1. The drain region 6 overlaps with a floating gate (first gate electrode) 3 in an S region. The source region 7 is provided apart from the floating gate 3 through an offset region 5a by a constant distance D.
The offset region 5a between the source region 7 and the floating gate 3 is P-typed in similar to the substrate 1 and has a higher density than that of a substrate surface region 1a.
The floating gate 3 is provided on a gate insulating film 2 which covers the regions 6, 7, 1a and 5a. In addition, the floating gate 3 overlaps with the drain region 6 in the S region and is provided apart from the source region 7 through the offset region 5a. An insulating film (a first layer insulation film) 8 having a thickness d1 of 500 Å is laminated on the floating gate 3. The insulating film 8 covers the drain region 6, source region 7, offset region 5a and floating gate 3. A control gate (second gate electrode) 9 having irregularities is provided through the insulating film 8. Concave and convex portions 9a and 9b of the control gate 9, which are formed by covering the floating gate 3, are eliminated by a second layer insulation film 10 for flattening. Only the convex portion 9b comes into contact with a third gate electrode 12 through a thin insulating film (third layer insulation film) 11 having a thickness of 500 Å.
Indicated at 13 is a fourth layer insulation film which covers a lower electrode film (not shown).
The non-volatile semiconductor memory is manufactured as follows, keeping in mind FIGS. 1(a)-1(f) are sectional views along section I--I' of the memory shown in FIG. 5.
As shown in FIG. 1 (a), a gate insulating film 2 having a thickness d3 of 100 Å is formed on a P-type Si substrate 1. Then, a polysilicon layer is deposited on the whole surface to become P- or N-typed by doping. Thereafter, a floating gate 3 is formed in a predetermined region by patterning. To form a first P-type impurity region 4 having a higher density than that of the Si substrate 1 and a second P-type impurity region 5, boron ions as P-type impurities are implanted in an approximately perpendicular direction to the surface of the Si substrate 1 [in a direction of an arrow A shown in FIG. 1 (a)] by using the floating gate 3 as a mask.
In that case, an accelerating energy for implanting boron ions is preferably 35 to 60 KeV, more preferably 50 KeV. A quantity of ion implantation is preferably 2×10 12 to 6×10 12 cm -2 .
As a result, there are formed on the substrate the impurity regions 4 and 5, and a substrate surface portion 1a having a lower density than the impurity regions 4 and 5 (the density of the substrate in which the ions are not implanted).
To form N-type drain and source regions 6 and 7 which are reversely typed to the Si substrate 1 and have higher densities than the first and second impurity regions 4 and 5, N-type arsenic ions are implanted in an oblique direction to the surface of the Si substrate 1 [in a direction of an arrow B shown in FIG. 1 (b)] by using the floating gate 3 as the mask.
In that case, an accelerating energy for implanting arsenic ions is preferably 60 to 100 KeV, more preferably 80 KeV. A quantity of ion implantation is preferably 1×10 15 to 5×10 15 cm -2 , more preferably 2×10 15 cm -2 .
Thus, an end portion 6a of the drain region 6 enters a substrate surface portion 1a on one end portion 3a side of the floating gate 3. On the other hand, an end portion 7a of the source region 7 is provided apart from the substrate surface portion 1a on the other end portion 3b side of the floating gate 3 through an offset region 5a having a constant distance D. In this case, the drain region 6 includes the first impurity region 4 to have N-type, while the source region 7 includes most of the portions other than the offset region 5a in the second impurity region 5 to have N-type. Then, SiO 2 , which is thermally oxidized or non-doped, is deposited to form an insulating film 8 around the floating gate 3 as shown in FIG. 1 (c). Thereafter, a second gate electrode (control gate) 9 is formed to cover the whole surface and is patterned.
To eliminate irregularities of the control gate 9 which are formed by covering the floating gate 3, an insulating film 10 having a thickness d4 of 5000 Å is formed on the whole surface of the control gate 9 for flattening [see FIG. 1 (d)]. Then, the whole surface is etched back to form the flat insulating film 10 as shown in FIG. 1 (e).
A newly thin insulating film 11 of high quality is formed at a thickness d2 of 200 Å over the whole surface of the insulating film 10. In this case, a preferred example of the insulating film 11 is an ONO film.
Then, a film to become an electrode is deposited and patterned to form a third electrode (third gate electrode) 12 [see FIG. 1 (f)]. The third electrode 12 comes into contact with only the convex portion 9b of the second gate electrode 9 through the thin insulating film 11 by coupling capacitance.
Thereafter, normal NOS manufacturing steps are started again. A SiO 2 film 13 containing phosphorus and boron is provided over the whole surface so as to form an electrode takeoff hole on each electrode portion, if necessary. Thus, manufacture is completed [see FIG. 1 (f)].
FIG. 2 shows a second embodiment of the present invention wherein the conditions of manufacture are changed such that electrons can be injected from a source to a floating gate without a third gate electrode.
As shown in FIG. 2, the density of an offset region 5b is made much higher than that of the offset region 5a in the first embodiment, so that Vth (threshold voltage) of the offset region in the channel region is equal to the potential of a second gate electrode for obtaining a floating gate potential necessary for injection. Consequently, a third gate electrode is not needed.
In that case, the P-type density of boron ions implanted in the offset region 5b is preferably 2×10 -- to 6×10 13 cm -2 .
FIG. 3 shows a third embodiment of the present invention which is a variant of the second embodiment, and a manufacturing method. As shown in FIG. 3 (c), the density of an offset region 5b is made higher than that of the offset region 5a in the first embodiment, and the thickness of a gate film in the offset region 5b is increased. Thus, Vth of the offset portion 5b is set to be equal to a control gate voltage which gives a floating gate potential necessary for injecting electrons from a source region 7. Consequently, a third gate electrode is not needed. In this case, the P-type density of boron ions implanted in the offset region 5b is preferably 2×10 13 to 6×10 13 cm -2 .
There will be described the manufacturing method with reference to FIG. 3.
FIGS. 3 (a) and (b) show the same manufacturing steps as in the first embodiment. In the subsequent steps, an insulating film 14 for flattening is formed such that a floating gate 3 is embedded therein [see FIG. 3 (a)].
Then, etchback is carried out to expose only the top of the floating gate 3 [see FIG. 3 (b)]. Then, a newly thin insulating film of high quality (for example, an ONO film) 15 is formed. A second gate electrode 9 to become a control gate is laminated on the insulating film 15. The subsequent steps are the same as the normal MOS manufacturing steps.
There will be described the cases where a cell layout example is to be further simplified by means of the non-volatile semiconductor memory at the sacrifice of a cell area, i.e., the third gate electrode is provided on the same surface (see FIG. 4), and where the cell layout example is to be simplified by reducing the cell area, i.e., the third gate electrode is provided on an intersecting point of first and second gate electrodes (see FIG. 5).
Referring to FIG. 4, a floating gate (first gate electrode) 17 is provided over a thin gate oxide film region and a thick oxide film (Field oxide film) region 16. A control gate (second gate electrode) 18 is capacitively-coupled with the floating gate in the thin gate oxide film region. A third gate electrode 19 is directly coupled with the floating gate in the thick oxide film region on the same surface. A P-type impurity region is indicated at 20.
In that case, the floating gate potential necessary for injecting electrons from a source is comprised of the potential applied from the control gate 18 and the potential applied from the third gate electrode 19 which is directly capacitively-coupled with the floating gate 17.
Referring to FIG. 5, a third gate electrode 23 is capacitively-coupled in an overlapping portion of a floating gate (first gate electrode) 21 and a control gate (second gate electrode) 22 in order to reduce the cell area as described above with reference to FIG. 1. In this case, the floating gate potential necessary for injecting the electrons from the source is comprised of the potential applied from the control gate 22 and the potential applied from the third gate electrode 23 which is indirectly capacitively-coupled with the floating gate 21 through the control gate.
FIG. 7 shows a cross-sectional view of the semiconductor memory shown in FIG. 5 along section line VII--VII'. As shown in FIG. 5, third gate 23 and floating ate 21 partially overlap at regions 200 (shaded black for clarity). FIG. 7 illustrates that in the overlapping regions where the insulation regions 300 are shaded black, capacitive-coupling occurs between floating gate 21 and a third gate 23.
With the above-mentioned structure,
(i) the length and impurity density of the offset region can easily be self-controlled,
(ii) the shortage of the potential applied from the control gate out of the floating gate potential necessary for injecting the electrons from the source is supplied by the third electrode which is directly or indirectly capacitively-coupled with the floating gate, so that writing can be stabilized,
(iii) the cell area can be reduced by making the third electrode overlap with the top of the first and second gate electrodes as shown in FIG. 1, and
(iv) if process is devised as described above, the electrons can be injected from the source without the third gate electrode.
As described above, there can be obtained effects that the length and density of the offset region can be self-controlled in a manner similar to that described in the background of the specification, and source programming can be carried out by means of only the control gate by changing the density of the semiconductor substrate on the underside of the floating gate in the channel region and in other regions without side wall electrodes, making the third electrode, which can be manufactured more easily, overlap in a three-dimensional basis. | A non-volatile semiconductor memory including a semiconductor substrate, drain and source regions which are provided on the surface of the semiconductor substrate and have P or N type differently from the semiconductor substrate, a floating gate (first gate electrode) for covering a portion of a channel region between the drain and source regions, the drain region being self-aligned with the floating gate, the source region being provided apart from the floating gate through an offset region in the channel region by a constant distance, whereby the drain and source regions are asymmetrical to each other through the floating gate, a control gate (second gate electrode) for controlling the surface potential of the whole channel region, and a third gate electrode provided above the control gate through an insulating film for substantially controlling the surface potential on the underside of the floating gate and in the vicinity thereof so that electrical writing and erasure can be performed, wherein the density of the offset region on the semiconductor substrate surface is made different from that of other portions on the semiconductor substrate surface so that electrons can be injected from a source. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is related to co-pending application entitle “Method, Processor and Computed Tomography (CT) Machine for Generating Images Utilizing High and Low Sensitivity Data Collected From A Flat Panel Detector Having an Extended Dynamic Range”, filed May 29, 2002 and having U.S. Ser. No. 10/157,282.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with Government support under NIH Grant No. CA 65637. The Government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] This invention relates to high spatial resolution, X-ray computed tomography (ct) systems.
[0005] 2. Background Art
[0006] The current state of imaging modalities used in these areas of dentomaxillofacial practice, with a particular emphasis on implantology, is described in the following subsections.
[0007] Implantology: Pre-Operative and Post-Operative Imaging
[0008] The use of dental implants is becoming an increasingly common treatment to replace missing teeth. Successful outcome of the treatment, osseointegration of the implant, depends heavily on precise presurgical planning. Since the functional load in implants can be high, it is important that the implant be placed in a position where it can contact cortical bone and at an angle where the forces are as perpendicular as possible. Selection of the appropriate size and inclination of the implant in both a bucco-lingual and mesio-distal direction requires precise knowledge of the anatomy of the proposed site, including its dimension in all planes, the presence of knife-edge ridges and undercuts, as well as the location of anatomic structures, such as the nasal fossae, the maxillary sinus, and the mandibular canal. An evaluation of the thickness of the cortical bone and the density of the medullary bone is also important to the success of the implant.
[0009] Acquiring the information needed for implant treatment planning requires some type of imaging examination. A number of imaging modalities have been used over the years, but they all have limitations and none are completely satisfactory.
[0010] Periapical radiography has enough resolution to depict trabecular bone pattern and the floor of the maxillary sinuses, but the images are limited in size and anatomic coverage and often suffer from geometric distortion. In addition, periapical radiographs are only two-dimensional images and do not provide information about the third, bucco-lingual, dimension.
[0011] Panoramic radiography is commonly used for implant site assessment because it is readily available, inexpensive, and provides wide coverage of the jaws. However, there are a large number of disadvantages to this technique that limit its usefulness for implant site assessment. The two primary problems are lack of information in the bucco-lingual plane and variability of the degree of magnification in different parts of the image due to changing distance between the rotational center, jaw structures, and film as the X-ray beam rotates around the head. Minor errors in positioning the patient's head in the machine can also exaggerate the degree of enlargement variability, particularly in the horizontal direction. Although dentists frequently try to overcome these magnification problems by having the patient wear a surgical stent with metal markers of a known size during the examination, this device is not adequate to solve all distortion errors.
[0012] Conventional (i.e., non-computed, “focal-plane” or “linear”) tomography has found an important application in the presurgical examination of proposed implant sites. Its major advantage over periapical and panoramic radiography stems from its ability to show bucco-lingual cross-sectional images. From these cross-sectional images, the dentist can estimate the spatial relationships of anatomic structures, bone height and width, and the inclination of the alveolar processes at the areas into which the implants are to be placed. Numerous studies have demonstrated that conventional tomography can depict the location of important anatomic structures, such as the mandibular canal, more accurately than panoramic radiography. Dimensional measurements are generally reliable with complex-motion tomography, and less so with linear-motion systems.
[0013] Conventional tomographs, however, have been reported not to be of diagnostic quality sufficient to allow identification of the canal in as many as 20% of cases. This is primarily due to the unavoidable blur that is inherent in the method, although some canals are poorly corticated and thus would be difficult to visualize with any technique. Another very important disadvantage of conventional tomography is that it is usually necessary to acquire multiple slices to ensure that the region of diagnostic interest is sampled adequately. Because each slice is acquired successively, the process is time-consuming and laborious, thus expensive, and it exposes the patient to a radiation dose that can be high, depending on the number of slices obtained.
[0014] X-ray computed tomography (CT) is a more sophisticated method for obtaining cross-sectional images than conventional tomography. It has been considered to be the most reliable technique for the assessment of bone height and width and localization of the inferior alveolar canal, mental foramen, nasopalatine canal, and maxillary sinuses. Consequently, it has been widely recommended for implant planning.
[0015] Conventional CT has its drawbacks, however. First, with its merely 2-D reformatted images, it may not clearly depict the inferior alveolar canal. Second, it is time-consuming: conventional CT requires more than 20 minutes to get all the axial slices for a dental implant study. With such a long scanning time, patient fatigue and patient swallowing start blurring the image. Third, conventional CT exposes the patient to a high radiation dose. Fourth, it is expensive. Fifth, it suffers from poor resolution, especially in the z-direction. Sixth, metal streak artifacts can occur in the presence of metallic dental restorations, requiring judicious selection of scan orientation and boundaries to minimize its occurrence.
[0016] Spiral CT is one of the most advanced imaging modalities available and is gradually replacing conventional CT. It is primarily used in the areas of medicine that require full body imaging, but is finding its use in dentistry as well. Spiral CT can generate not only 2-D cross-sectional images, but also fully 3-D images. Its 3-D capability is due to the fact that the X-ray source and detector continuously move along a spiral path relative to the body, thus acquiring data that are essentially 3-D. Spiral CT has been successfully used for the presurgical assessment for implant treatment planning.
[0017] However, the use of spiral CT in dentistry is hampered by its high cost and radiation dose, low spatial resolution in axial direction, and metal streak artifacts. In order to overcome some of the disadvantages, specifically high cost and radiation dose, two dental imaging methods have been proposed: Tuned-Aperture Computed Tomography (TACT™) and Ortho-CT.
[0018] TACT™, “an inexpensive alternative to CT,” is based on the theory of tomosynthesis. The relatively low cost of TACT is party due to its simplicity and partly due to its use of equipment that already exists at the facility. The use of TACT in implantology has been suggested, but no controlled studies have yet been performed. Nevertheless, its disadvantages in implant planning can be assessed from its characteristics. First, TACT requires the use of fiducial markers to estimate the imaging geometry and perform the reconstruction. This adds to the complexity of operating the instrument. Second, it uses CCD sensors of a low contrast resolution. Third, TACT does no have actual 3-D capabilities, but so-called pseudo-3D; 2-D images are being displayed from different angles, simulating varying projection geometries and providing some perception of three dimensions to the viewer. So, with TACT, the gain in cost-effectiveness is offset by a lower quality scan.
[0019] Ortho-CT is another potentially inexpensive alternative to spiral CT. Ortho-CT is basically a small cone-beam CT unit obtained by modifying a maxillofacial radiographic unit called Scanora® (Soredex, Helsinki, Finland) in order to acquire a “partial” CT scan.
[0020] In this context, the term “partial CT scan” refers to a cone-beam CT scan using a circular orbit, which, in addition to having the usual cone-beam incompleteness problem (i.e., a circular orbit does not satisfy Tuy's completeness conditions), is more incomplete in the sense that the data is insufficient for quantitatively reconstructing 3-D cross-sectional images to the use of a detector and scan geometry that do not measure all necessary rays through the object.
[0021] As an example, the “fan-beam scan” or central slice of the circular-orbit cone-beam scan is complete if the detector and scan geometry measure all parallel rays through the object at angles ranging from 0 to 180 degrees.
[0022] In the Ortho-CT device, a complete set of parallel rays is not measured at any view angle. It has a good spatial resolution; the resolving power at an MTF of 0.5 can be 1 lp mm −1 and the visual resolution limit about 2.0 lp mm −1 . Radiation dose is low; skin dose is almost the same as with panoramic radiography and several dozen times lower than with conventional CT.
[0023] However, the applicability of Ortho-CT in implant planning is limited for four reasons. First, it can image only small areas (32×38 mm). If a larger area needs to be imaged, multiple scans are required. Second, its contrast resolution is so low that Ortho-CT is incapable of discriminating soft tissue. Third, its values are only relative and do not correspond to the absolute values of bone density. This is a consequence of its use of incomplete data. Fourth, although its behavior in the presence of metal fillings has not been reported on, it is expected that it suffers from metal streak artifacts.
[0024] In addition to presurgical planning of implants, there is a need for long-term maintenance and monitoring of tissue health around the implant after surgery has been performed. Peri-implantitis can progress around dental implants in a manner similar to the progression of periodontitis around natural teeth. If the determination of a failing implant could be made before the implant actually fails, therapeutic intervention might prevent further deterioration of implant support and loss of the implant. A long-standing goal of periodontal research is to find a diagnostic tool with a high sensitivity for detecting subtle disease activity around teeth. In particular, the detection of subtle changes in bone mass may be of great value for evaluating progressive periodontal disease or bone gain/loss after therapy.
[0025] Conventional radiography is routinely used by periodontists for the postsurgical assessment of the implant. It can display the mesial and distal aspects of the implant site, but it provides little information about the facial and lingual aspects of the implant site because of the obscuring effects of the radiopaque implant material. Its other major limitations include the subjective interpretation of the radiographic image, lack of sensitivity, and the inability to quantify bone mass.
[0026] Digital subtraction radiography can quantify bone mass and thus can be used for postsurgical implant assessment. The method involves taking two separate radiographic scans and then subtracting them. The two images are made at different times and must be as identical as possible. The exposure factors and processing parameters that affect density and contrast must be consistent between the two scans and the projection geometry must be duplicated as nearly as possible All this makes the method laborious and inefficient, especially when the medium is film, which is often the case. Finally, it cannot overcome the obscuring effects of a metal implant sufficiently to allow reliable detection of facial and lingual bone loss at implant sites.
[0027] The Temporomandibular Joint (TMJ)
[0028] When a patient presents complaints referable to the TMJ region, the findings from the clinical examination may indicate the need for imaging to aid in diagnosis and treatment planning. The osseous structures can be visualized with a variety of imaging techniques, including plain and panoramic radiography, conventional tomography and CT, depending on the degree of detail required.
[0029] Conventional tomography plays a significant role in TMJ imaging. Tomographic studies in the lateral and coronal planes demonstrate osseous components of the joint, whereas arthrotomographic examinations provide information about the status of the soft-tissue intra-articular disk. However, tomography of the TMJ is technically demanding because the imaging protocol must be customized for each patient due to the variability of condylar angles. Images made with linear-motion machines may also be suboptimal due to streaking artifacts and incomplete blurring of adjacent structures.
[0030] The use of computed tomography for TMJ imaging has generally been reserved for complex cases as a result of its relatively high cost and high radiation dose. Evaluation of articular disk position and function is usually performed with magnetic resonance imaging or arthrotomography, again both expensive techniques.
[0031] Detection of Facial Fractures
[0032] Another important problem in dentistry is the determination of the location and displacement of facial fractures in patients who have suffered trauma to the maxillofacial region. Complex trauma to the facial skeleton requires both highly qualified clinical knowledge and an accurate imaging technique.
[0033] Conventional radiography is unsuitable for the task because it requires multiple scans to obtain all the views that are necessary for evaluation. Even with a series of radiographs, it is sometimes difficult to detect subtle fractures. And conventional tomography, while theoretically capable of demonstrating complex anatomy better than planar projection radiographs, has generally been superseded by CT in most hospitals.
[0034] Spiral CT imaging is a better solution for detection of facial fractures. Only one spiral CT scan is needed for the examination, and it does not require movement of the patient to obtain multiple views. It is very fast and can scan the entire midface and the frontal sinus in less than a minute. Thus, it allows the diagnostician to move on to other essential diagnostic and therapeutic interventions without delay. Also, it allows for further processing of the data without requiring the patient's continued presence in the CT unit. Finally, spiral CT produces images of superior quality and can be used to generate 3-D images that can be rotated on a video screen to demonstrate the anatomy and pathology from all angles.
[0035] However, the use of spiral CT for detecting facial fractures has drawbacks. It is costly and it exposes the patient to a high radiation dose. It also suffers from metal streak artifacts, which can result in misleading scans of the facial complex.
[0036] Lesions and Diseases of Soft Tissue in the Head and Neck
[0037] In addition to imaging of the bony structures of the maxillofacial complex, a very important task is the imaging of the soft tissues in the head and neck. Particularly important is imaging of inflammations, cysts, and tumors.
[0038] While conventional radiography produces adequate bone images, it provides little information regarding soft tissues as a result of the inability of film-screen systems to record X-ray attenuation differences of less than 2%.
[0039] CT, however, is much more effective at separating subtle tissue contrast difference (as low as 0.5%). CT can differentiate not only soft tissue from bone, but also various types of soft tissues from each other. Consequently, CT has found a very important application in the evaluation of the presence and extent of clinically suspected pathology in the head and neck, including tumors, cysts, and inflammations. When additional information concerning the soft tissues is required, an intravenous contrast agent can be used. Cavalcanti et al. have successfully used spiral CT to measure the volume of oral tumors.
[0040] Although CT has proven superior in many aspects to other modalities in this application, its use has been limited by three factors: cost, radiation dose and metal streak artifacts. In addition, the spatial resolution available in current CT scanners, which are designed primarily for full-body imaging, may not be optimal for lesions in the head and neck.
[0041] MRI has also been used to image soft tissue of the head and neck. Some advantages of MRI over CT include better contrast resolution, absence of artifact degradation from dental restorations, visualization of major vessels without intravenous injection of contrast material, and direct, three-plane imaging without patient repositioning. MRI, however, is more expensive than CT, and requires a longer time to obtain a scan. To date, there is no general consensus about which imaging technique is optimal for use in diagnosis of lesions in the head.
[0042] Reconstructive Facial Surgery
[0043] Surgery of craniofacial deformities is a complex task that requires careful preoperative planning and specific, detailed information on patient's pathology and anatomy. The goals of maxillofacial surgery are not limited to treating the condition of bone, but extend to improving both the morphology and function of soft tissues, such as facial appearance for the patient. It is necessary, therefore, to ascertain how the proposed alteration of bone will affect the form and function of the surrounding soft tissue. Effective planning of reconstructive facial surgery requires not only adequate imaging of the bone and soft tissue but also the means of interpreting these images in combination to predict how the surgical alteration of bone will affect soft tissue.
[0044] Radiography has been used with a certain amount of success for planning facial reconstructive surgery. However, facial reconstructive surgery presents a three-dimensional problem of anatomical rearrangement and cannot be effectively planned using two-dimensional images. Morever, some facial and skeletal anomalies, specifically those involving facial asymmetry, are not amenable to analysis using only two-dimensional images.
[0045] CT and MRI can supply detailed, three-dimensional information on the patient's anatomy, and have therefore become the methods of choice in maxillofacial surgery planning. They are typically used in conjunction with computer software that shows the predicted three-dimensional rendered postoperative facial surface. However, both are expensive. In addition, CT suffers from metal streak artifacts and exposes the patient to a high radiation dose while MRI is not particularly useful for examining bony structures.
[0046] Several devices have been conceived for dentomaxillofacial imaging. Ortho-CT is a vertically oriented device that acquires a partial CT scan, and while spatial resolution is adequate, the device suffers from artifacts due to the incomplete nature of the scan and does not produce quantitatively accurate estimates of attenuation (necessary for assessing bone quality).
[0047] TomCAT is a cone-beam imaging device in which the patient lies supine on an imaging table similar to conventional spiral or single-slice CT instruments. The TomCAT uses an image intensifier and CCD camera for the detector—a combination that has relatively poor dynamic range (reducing quantitative accuracy) and also suffers from spatial distortions. Although images reconstructed from TomCAT have spatial resolution similar to conventional general-purpose CT instruments, contrast resolution is quite poor and images appear to suffer from a great deal of X-ray scatter (and perhaps veiling glare from the image intensifier).
[0048] Individual methods are known to be close to the techniques described herein (e.g., Wagner's method for scatter estimation and correction).
[0049] The following U.S. patents are deemed to be relevant to the present invention: U.S. Pat. Nos. 5,390,112; 5,615,279; 6,018,563; 5,909,476; 6,118,842; 6,075,836; and 5,999,587. The following U.S. patents are deemed to be of less relevance to the present invention: U.S. Pat. Nos. 5,927,982; 6,094,467; 6,125,193; 5,461,650; 4,812,983; 4,590,558; 4,709,333; 5,243,664; 5,798,924; 6,035,012; 5,293,312; 5,390,112; 5,615,279; 5,644,612; 5,751,785; 5,042,487; and 5,909,476. The following U.S. patents are also deemed to be relevant: U.S. Pat. Nos. 5,778,045; 5,793,838; 5,805,659; 5,815,546; 5,864,146; 5,878,108; 5,881,123; 5,903,008; 5,921,927; 5,949,846; 5,970,112; 5,995,580; 6,052,428; 6,101,234; 6,101,236; 6,104,775; 6,118,841; 6,185,271B1; 6,285,733B1; 6,285,740B1; 6,289,074B1; 6,292,527B1; 6,298,110B1; 6,324,246B1.
SUMMARY OF THE INVENTION
[0050] An object of the present invention is to provide an improved high spatial resolution X-ray computed tomography (ct) system.
[0051] In carrying out the above object and other objects of the present invention, a high spatial resolution X-ray computed tomography (CT) system is provided. The system includes a support structure including a gantry mounted to rotate about a vertical axis of rotation. The system further includes a first assembly including an X-ray source mounted on the gantry to rotate therewith for generating a cone X-ray beam and a second assembly including a planar X-ray detector mounted on the gantry to rotate therewith. The detector is spaced from the source on the gantry for enabling a human or other animal body part to be interposed therebetween so as to be scanned by the X-ray beam to obtain a complete CT scan and generating output data representative thereof. The output data is a two-dimensional electronic representation of an area of the detector on which an X-ray beam impinges. A data processor processes the output data to obtain an image of the body part.
[0052] The second assembly may include a grid positioned adjacent the detector to reduce scatter.
[0053] The first assembly may include a shadow mask for spatially modulating the source and to estimate residual scatter.
[0054] The X-ray source and the X-ray detector may be mounted on the gantry to rotate therewith along an elliptical path.
[0055] The first assembly may be capable of irradiating the body part with two different X-ray spectra.
[0056] The first assembly may further include a source collimator mounted adjacent the X-ray source.
[0057] The system may further include a scatter rejection collimator mounted on the gantry to rotate therewith.
[0058] The system may further include a device for controlling position of the source collimator based on position of the detector relative to the source.
[0059] The detector may include a converter for converting X-ray radiation into visible light.
[0060] The detector may further include a hydrogenated amorphous silicon (aSi:H) detector array.
[0061] The data processor may be programmed with a statistical image reconstruction (SIR) program.
[0062] The entire body part may be scanned by the X-ray beam in a single scan.
[0063] The processor may be programmed with a penalized weighted least squares (PWLS) reconstruction program.
[0064] The processor may further be programmed with a dual energy penalized weighted least squares (DE PWLS) reconstruction program.
[0065] The detector may generate high and low energy data at each rotation angle of the gantry.
[0066] The processor may be programmed to obtain the high and low energy data from the detector and generate the image using the obtained data.
[0067] The system may further include means for correcting for body part motion at each rotation angle of the gantry.
[0068] The means for correcting may include a device that measures relative motion of the body part to obtain measurement data. The processor may be programmed with an image reconstruction program which utilizes the measurement data.
[0069] The body part may be a head, and the system may be a dentomaxillofacial system.
[0070] The gantry may be mounted to move vertically along the axis of rotation.
[0071] The gantry may be mounted to pivot along an accurate path about a point on the axis of rotation.
[0072] The system may further include a device for offsetting the detector in a plane substantially perpendicular to the axis of rotation relative to the gantry.
[0073] The system may further include an arm coupled to the detector and the source collimator for controlling position of the source collimator based on position of the detector.
[0074] The system may further include means for stabilizing motion of the head.
[0075] Various imaging modalities have been used in the dentomaxillofacial fields over the past few decades—none with entirely satisfactory results. The system described herein will find its most immediate use in pre-operative site assessment for dental implants and in post-operative assessment of a failed implant. It is further anticipated that the system will lead to the advancement of scientific knowledge and enable further discoveries in TMJ imaging, detection of facial fractures and lesions and diseases of the soft tissue in the head and neck, and imaging used in reconstructive facial surgery.
[0076] The above object 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 when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0077] [0077]FIG. 1 a is a schematic view of a system constructed in accordance with the present invention wherein a patient is seated in a chair (a chin-rest is not shown); the system features cone-beam geometry, aSi:H detector array, and PWLS and DE PWLS reconstruction methods;
[0078] [0078]FIG. 1 b is a schematic view illustrating an elliptical sensing orbit of an X-ray source and a detector of the present invention;
[0079] [0079]FIG. 1 c is a schematic view of a head motion detection subsystem of the present invention;
[0080] [0080]FIG. 2 is a bottom view of a rotating arm portion of the gantry of the present invention; source, source collimator, detector, shadow mask, and detector translation track are illustrated; detection position controls position of source collimator through a mechanical arm such that only the appropriate portion of a patient's head or neck is irradiated with X-rays;
[0081] [0081]FIG. 3 is a side view of the rotating arm portion of the gantry shown in FIG. 1; the entire arm can either move up or down vertically (in addition to rotating) or can pivot about the point shown so that a “complete” tomographic dataset can be acquired;
[0082] [0082]FIG. 4 is a graph which shows a sinogram sampling pattern for the fan-beam slice of a device with no detector offset; each sinogram position (angle and radius) is essentially sampled twice;
[0083] [0083]FIG. 5 is a graph which shows a sinogram sampling pattern with detector offset equal to one-half the detector width; in this case, each position in the sinogram is sampled once (or relatively the same number of times as for the detector at zero offset); size of the field-of-view, however, is considerably larger;
[0084] [0084]FIG. 6 is a graph which shows a sinogram sampling pattern with the detector at an intermediate offset position; in this case, the size of the field-of-view is greater than that for the detector at zero offset and rays nearer the center of the object (the thickest part, generally) are sampled twice while those nearer the periphery only once; this has the effect of improving the signal-to-noise characteristics of the data and is similar, although not exactly the same, as use of a bowtie filter in conventional CT;
[0085] [0085]FIGS. 7 a and 7 b are side and front schematic views, respectively, of a coarse-grained, one-dimensional detector collimator for rejecting X-ray scatter; vanes of the collimator are focused on a focal spot of an X-ray source; an orthogonal set of vanes can be added for improved scatter rejection;
[0086] [0086]FIG. 8 is a schematic view of a shadow mask that can be used to estimate residual scatter and can be left in place during acquisition of the patient's diagnostic data; additional spatially-variant filtration could be placed within the clear aperture of this mask in order to collect X-ray projection information using two or more X-ray spectra in order to correct for beam hardening and accurately assess bone-mineral content;
[0087] [0087]FIG. 9 is a schematic graphical view of a mask for estimating residual scatter computed from a shadow mask consisting of an array of absorbing balls; regions of the mask are slightly smaller than balls;
[0088] [0088]FIG. 10 is a schematic graphical view of a mask for restoring projection data or for use directly in reconstruction algorithms such as penalized weighted least squares (PWLS) so that regions on the detector corresponding to the shadows of the balls are ignored for image reconstruction;
[0089] [0089]FIG. 11 is a projection image of an object acquired with a ball-array shadow mask interposed between the source and the object;
[0090] [0090]FIG. 12 illustrates spatial distribution of residual scatter estimated using the mask shown in FIG. 9, data shown in FIG. 11, and an appropriate interpolation scheme;
[0091] [0091]FIG. 13 shows projection data of FIG. 11 that has X-ray scatter removed and has been restored such that the ball array is not evident;
[0092] [0092]FIGS. 14 a - 14 c illustrate detector masking so that a “dark signal” is present along each data line even with illumination of the detector with the X-ray source; resulting values from pixels within this region can be used to correct voltage offset or “pedestal” for every detector element on a particular data line; FIG. 14 a is a back view of the detector; FIG. 14 b is a front view with a scintillator layer; and FIG. 14 c is a front view with absorbing strips; and
[0093] [0093]FIGS. 15 a - 15 d illustrate four X-ray CT slices of a human head acquired using prototype tomography for dentomaxillofacial imaging.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0094] A system of the present invention possess a wide spectrum of properties to be used effectively both in implantology and for the applications described. The properties are summarized below in Table 1.
TABLE 1 1. High contrast-resolution for both bone and soft tissue; 2. High spatial resolution in X, Y, and Z directions; 3. Low radiation dose; 4. Metal streak artifacts removal; 5. Quantification of soft tissue and bone densities and their changes; 6. Full 3-D capabilities; 7. Ability to generate axial, coronal, sagittal, and oblique planes images; 8. Ability to produce undistorted images with linear measurements preserved; 9. High scanning speed to avoid body movement artifacts; 10. Relatively inexpensive; and 11. Easy to use.
[0095] None of the previous dentomaxillofacial imaging modalities possesses all these properties, and the practitioner has historically been face with various trade-offs in the decision as to which modality to use.
[0096] The new system features all the properties from Table 1, and is therefore expected to become the modality of choice in dental implantology and other clinical tasks that involve the dentomaxillofacial complex.
[0097] A preferred system of the invention is generally indicated at 10 in FIG. 1 a . Its building blocks are: 1) a cone-beam data acquisition and image reconstruction devices including a computer 12 with a display 14 ; 2) a detector assembly, generally indicated at 16 , including an amorphous silicon (aSi:H) detector array coupled to a source assembly, generally indicated at 18 , including an X-ray source, both assemblies being mounted on a rotating gantry, generally indicated at 20 , and fitted with appropriate X-ray filtration, collimation, shadow masks, etc.; 3) the computer 12 or data processor is programmed with a) a penalized weighted least squares (PWLS) reconstruction program and/or b) a dual energy penalized weighted least squares (DE PWLS) reconstruction program when precise information regarding soft tissue and bone densities is needed.
[0098] Cone-Beam Geometry
[0099] Compared to the conventional fan-beam geometry, a cone-beam geometry is used in the present invention due to its high efficiency in X-ray use, inherent quickness in volumetric data acquisition, and potential for reducing the cost of CT machines. Conventional fan-beam scans are obtained by illuminating an object with a narrow, fan-shaped beam of X-rays. The X-ray beam generated by the tube is focused to a fan-shaped beam by rejecting the photons outside the fan, resulting in a highly inefficient use of the X-ray photons. Further, the fan-beam approach requires reconstructing the object slice-by-slice and then stacking the slices to obtain a 3-D representation of the object. Each individual slice, therefore, requires a separate scan and separate 2-D reconstruction.
[0100] The cone-beam technique, on the other hand, requires only a single scan to capture the entire object with a cone of X-rays 22 . The time required to acquire a single cone-beam projection is the same as that required by a single fan-beam projection. But since it takes several fan-beam scans to complete the imaging of a single object, the acquisition time for the fan-beam tends to be much longer than with the cone-beam. This is important because the more time the patient is subjected to the scanning process, the more likely it is that the patient may move or swallow, blurring the scan. Although it may be possible to reduce the acquisition time of the fan-beam method by using a higher power X-ray tube, this increases the cost and bulkiness of the scanner.
[0101] Hydrogenated Amorphous Silicon Detector (aSi:H) Arrays
[0102] The imaging detector 16 used in the system 10 is a large-area array constructed from hydrogenated amorphous silicon (aSi:H) as described in the above-noted application. The detector 16 is a “self-scanned” array of n-i-p photodiodes and thin-film transistor switches. The integrated-flux mode X-ray detector 16 is constructed by mating a flat-panel photodiode array with the appropriate scintillator.
[0103] The detector 16 is both inexpensive and capable of generating high-quality images. Essentially the same technology is used to construct active-matrix, flat-panel computer displays and large-area document imagers. They are replacing film and image-intensifiers in conventional radiography and fluoroscopy applications. Several companies currently produce detector arrays for commercial sale. Several years ago it was predicted that these devices could be used for tomography and for attenuation correction applications in PET and SPECT.
[0104] Although it has been recently suggested that a special image intensifier can be coupled with a CCD camera for use in a cone-beam-based dental CT scanner, the characteristics of aSi:H-based flat panel detector arrays make them a much better choice for this application. The aSi:H detector arrays offer three distinct advantages. First, the aSi:H flat panel detectors, unlike image intensifiers, do not create geometric distortions that must be addressed when processing the data. Second, flat panel detectors are available in sizes up to 40×40 cm, which is large enough to cover the entire head, whereas image intensifiers have relatively smaller diameters, creating “truncated view” artifacts. Third, flat panel detectors afford a greater dynamic range than that offered by the image intensifier+CCD camera approach.
[0105] The a-Si photodiode array/scintillator combination is not the only type of flat-panel imaging detector that can be used in the system 10 described here. In particular, direct detection arrays, which have an X-ray converter such as lead iodide or amorphous selenium (or other suitable converter), can be used. These devices have no intermediate light conversion step and instead convert X-rays to an electrical charge that is read out by the array. Although direct detection devices may eventually offer advantages such as higher spatial resolution, they are at present investigational having detection efficiency that is too low at the energies used in tomography applications.
[0106] The vertically-oriented, high-resolution tomograph system 10 is primarily provided for dentomaxillofacial imaging applications. The basic system 10 includes a support structure, generally indicated at 11 , including the gantry 20 having an arm 21 , which, in this case, adjusts to accommodate different size patients and a rotating arm (as shown in FIGS. 1 c , 2 and 3 at 24 ) to which is affixed an X-ray source 26 and a controlled source collimator 28 (i.e., FIG. 2) of the assembly 18 on one end of the arm 24 and on the other end of the arm 24 , the assembly 16 including a 2-D position-sensitive X-ray detector 30 and a scatter-reducing collimator 32 . The system 10 also includes a device, generally indicated at 34 , for moving the detector 30 with respect to the arm 21 to accommodate different patient head sizes and to reduce the effect of detector non-uniformities. The device 34 includes a detector translation track 35 . In order to acquire images that quantitatively assess the quality (i.e., mineral content) of bone, the instrument can switch between two X-ray tube potentials or an X-ray filter 36 can be interposed that spatially modulates the source (i.e., a “shadow mask”). At each rotation angle of the gantry arm 21 , the X-ray source 26 irradiates the object with two different X-ray spectra and two images are recorded from the detector 30 .
[0107] More detailed drawings of the assemblies 16 and 18 are shown in FIGS. 2 and 3 wherein the detector 30 is translated along the track 35 to various offset positions and the position of the detector 30 controls the position of the source collimator 28 by the use of the mechanical arm 24 . The purpose of these features are discussed hereinbelow.
[0108] To accomplish scanning, the patient sits upright in a chair 40 of the support structure 11 . The chair may be vertically adjustable. The patient may, for purposes of reducing head-motion during the scan, bite into an immobilizing apparatus 42 (i.e., FIG. 1 c ) affixed to the tomograph (e.g., a dental impression tray filled with impression material as used in conventional linear tomography). During set-up for the scan, the operator preselects the desired X-ray tube (i.e., source) potential (kV) and the instrument performs a “scout scan” as described in more detail below. From the scout scan, not only can the optimum exposure time for each frame be estimated (as it is done in current practice), but the appropriate detector offset can also be computed. In order to acquire a dataset that is tomographically complete, the offset allows use of a detector that is smaller than would be ordinarily necessary to collect a tomographically complete dataset of the entire head (complete with respect to the “fan-beam” slice). It also provides the desirable added feature of reducing detected scatter as described below.
[0109] Correction for the Head Motion
[0110] Although the instrument may utilize a device to stabilize the motion of the patient's head, such as the bite plate, as illustrated in FIG. 1 c at 42 , it is nonetheless expected that the patient will still slightly move during the scan (which will typically last between 30 and 90 seconds). This residual head motion will cause the data acquired at different angles to be inconsistent with each other, thus introducing artifacts in the reconstructed images. These artifacts, referred to as “patient motion artifacts,” typically result in images that are blurred. In its mild form, the blurring effectively reduces the spatial resolution of the device, while in severe cases it can render the image useless, and needs to be corrected for as the spatial resolution is at premium in the imaging of the dentomaxillofacial complex.
[0111] A solution for correcting the head motion artifacts will now be described. The method consists of two parts: 1) a device that measures the relative motion of the head at each projection; and 2) software method that incorporates these measurements into image reconstruction.
[0112] The head is treated as a rigid body with six degrees of freedom. The motion of the head is measured with a device depicted in FIG. 1 c . It consists of a sensor 44 that records the motion of the head. The recordings of the device are synchronized with the image acquisition sequence of the detector 30 so that for each detector position, the position of the head is known.
[0113] These measurements are then fed into the computer 12 programmed to perform the image reconstruction method. The movement of the head in the coordinate system of the scanner can be looked at as the (equivalent in magnitude but opposite in direction) movement of the scanner (source 26 and detector 30 ) in the coordinate system of the head. The expressions for all image reconstruction algorithms (e.g., filtered back projection, statistical image reconstruction methods, etc.) are typically written in the coordinate system of the reconstructed object (in our case the head) and involve the coordinates of the X-ray source 26 and detector 30 in this coordinate system. In the proposed method, these coordinates of the X-ray source 26 and detector 30 are different at each angle, where the difference corresponds to the measured head motion.
[0114] Dual-Energy Imaging for Bone-Quality Assessment
[0115] In addition to single-energy scanning, where as in conventional instruments attenuation measurements through the object are taken using a single X-ray spectrum, the system of the present invention is capable of acquiring and processing data using two X-ray spectra. The advantages are two. First, it is well known that the technique can provide superior corrections for “beam-hardening” or the fact that the effective energy of the broadband X-ray bremsstrahlung radiation increases as the X-ray beam traverses soft tissue and bone and the lower energy X-rays are preferentially absorbed.
[0116] Second, the method, when combined with the appropriate image reconstruction technique (e.g., Penalized Weighted Least Squares), can provide good estimates of bone-mineral contact as a measure of bone quality (which is especially important in dental implantology).
[0117] There are numerous methods for accomplishing imaging using two spectra. A potentially important technique can generate two spectra by spatially modulating the X-ray beam using a “shadow mask.” This device, a filter 36 that spatially modulates the X-ray beam, has been used in order to acquire dual-energy data simultaneously. The shadow mask 36 used here, however, can contain both filtration elements for dual-energy data acquisition as well as “beam-stops” for estimating residual scatter (see below).
[0118] Complete Cone-Beam Scan Orbits
[0119] To acquire a set of cone-beam projection data that satisfies the cone-beam completeness conditions, the focal-spot of the X-ray source should intersect every plane through the object. Obviously, a circular orbit does not satisfy these conditions (although usable CT images have been obtained with circular orbits). There are a number of simple orbits that can be used with the described device to satisfy these conditions.
[0120] As two examples, the source 26 and the detector 30 can move axially during rotation to accomplish helical cone-beam scanning or the source 26 and the detector 30 can “wobble” to such an extent that the focal-spot of the source 26 intersects every plane passing through the desired axial extent of the scan (FIG. 3). This additional motion can be accomplished in a variety of ways from using an additional motor to move the gantry 20 vertically or wobble it during rotation by using a mechanical cam arrangement (no shown) that transfers some of the torque of the motor used to rotate the gantry 20 into the appropriate force.
[0121] [0121]FIG. 3 shows an optional pivot 50 on vertical axis of rotation 51 for gantry movement as indicated by arrows 52 . Alternatively, the gantry 20 moves vertically as indicated by arrows 54 .
[0122] The system 10 is capable of scanning a head along an elliptical orbit, as shown in FIG. 1 b . An elliptical orbit is better suited for head imaging as the head is typically elliptical in shape. This is of particular interest when an offset detector arrangement is used as described herein. The elliptical arrangement allows the detector 30 to capture more data while moving along the sides of the head in comparison to a circular scan. The data acquired in this fashion is then fed into the data processor or computer 22 programmed with a modified image reconstruction program.
[0123] Using a “Scout-Scan” to Estimate Exposure and Determine Best Detector Offset
[0124] It is common practice to use a low-current scan at the desired X-ray tube potential in order to determine whether patient positioning is proper and to estimate an appropriate exposure. In addition to using the scout scan for these purposes, the system 10 of the invention also uses the scan to determine an appropriate offset for the detector 30 in order to (1) ensure that a complete dataset is acquired, (2) ensure that enough information is available to calculate detector positions such that the tradeoff between X-ray scatter and improved information resulting from measuring some rays twice is appropriate.
[0125] Using an Offset Detector to Reduce Necessary Size, Improve Sampling and Decrease X-Ray Scatter
[0126] The system 10 is capable of using a detector having a width smaller than that ordinarily required to obtain a complete tomographic dataset. Typically, in fan-beam and cone-beam tomography, the X-ray image or projection of the object in each view must encompass the entire object. This, depending on the system geometry, can require use of a detector that is quite large, which increases system cost. It is well known that a detector of smaller size can be used. Specifically, a detector half of the width can be used along with a single rotation plus an angle equivalent to the cone-angle to acquire a dataset that is essentially complete (in the sense that it contains the same data contained in the scan using a full-size detector for the central slice). Data from the half-detector geometry can be reconstructed using a modified image reconstruction algorithm.
[0127] In addition to cost-savings of using such an arrangement, the detector 30 can be combined with source collimation to irradiate only the portion of the object containing line segments connecting the source 26 with the detector 30 . This arrangement, as noted below, will reduce X-ray scatter.
[0128] Rather than using a detector having a fixed offset, as has been used previously, the detector 30 in this system 10 can move along the track 35 (FIG. 2 wherein a field of view of the system 10 is indicated at 46 ) to achieve a variable offset in order to collect a complete dataset. The offset of the detector 30 can either (1) be predetermined and set once per scan by the operator, or (2) be moved by motor control to positions determined from the scout scan or from previous frames of the diagnostic scan. The advantage of this approach is that the detector 30 can be optimally positioned for each object scanned. For example, the detector 30 may be of such a size that projections of the object “almost” fit the width. In this case, the detector 30 may not need to be displaced by a half-detector width. The advantage for doing so is that some portions of the object will be sampled twice by the X-ray source 26 and the detector 30 during the scan reducing noise due to the quantum nature of X-ray detection.
[0129] FIGS. 4 - 6 show examples of the sinogram sampling pattern of the fan-beam slice for detector offsets ranging from none to one half-detector width. When the detector 30 has no offset, the entire sinogram is sampled twice. At full offset, it is only sampled once per rotation. At positions between these extremes, a portion of the object (generally the thickest part) is sampled twice, which can reduce noise.
[0130] First-Order Scatter Reduction Using a Coarse, High-Transparency Detector Grid
[0131] Scattering—both Compton and coherent—is the most prevalent interaction mechanism of X-ray photons with tissues of the body. While scattering contributes significantly to the observed attenuation of a beam of X-ray photons through the body, a large fraction of the scattered photons escape the body and are subsequently detected at the X-ray detector. Recording these photons, whose direction has been altered considerably from the incident X-ray beam, leads to serious reductions in the contrast-resolution of X-ray CT.
[0132] In conventional fan-beam or spiral-scan tomography, Compton-scatter is reduced by two methods: 1) the X-ray source is finely collimated so that it only illuminates a narrow region subtended by the strip-detector (either single- or multi-slice) used in these systems, and 2) additional detector collimation may be used to reduce scatter. The additional collimation may either be a detector slit or a set of fan-beam channels, which in older xenon gas-based detectors were actually part of the detector.
[0133] In cone-beam tomography, scatter can be much more severe because the source irradiates a much larger section of the object. Therefore, scatter comes not only from a narrow axial region (or slice) but also from the entire irradiated axial extent. In conventional film radiography, scatter can be reduced by using a variety of scatter rejection grids. These grids are usually comprised of alternating strips of aluminum and lead foil. The strips are focused linearly to the focal spot of the X-ray source and reduce the detection of scattered radiation because, as with the use of collimation for spiral and conventional CT, the ray-path of scatter will typically not come a direction consistent with the X-ray source and will therefore be absorbed by one of the lead strips.
[0134] The problems with using these grids for cone-beam tomography is that their transparency—the ratio of the exiting flux to the incident X-ray flux—is relatively low due to both a large number of lead strips (typically 85 or 103 per inch), which must be relatively thick to absorb X-rays of the appropriate energies, and the aluminum used as the interspacer.
[0135] An effective scatter rejection grid with much higher transparency can be constructed with lead foil and machinable polyacrylimide foam—a technique that has been used for constructing slice collimators for SPECT. The basic construction is similar to the conventional grid for radiography described above: each grid or collimator 32 is a stack of absorbing septa 31 , focused on the focal-spot of the X-ray source assembly 18 , separated by a low-attenuation spacer 34 as shown in FIGS. 7 a and 7 b . In this case, however, the layers 31 of the scatter rejection grid 32 are much farther apart (perhaps a maximum of 10 foil-foam layers 31 per inch rather than 85). The ratio of the grid, or the ratio of the depth of the linearly focused absorbing septa 31 to the space between septa, can be the same; therefore, the scatter rejection properties can be similar but the transparency much higher (the attenuation of foam is much smaller than aluminum). Two linearly focused grids placed orthogonally with respect to one another can be used to reduce scatter to an even greater degree.
[0136] Another method for constructing the crossed grids is to cut slots halfway through each absorbing septum in order to accept corresponding slots cut into orthogonal septa. This results in a largely self-supporting grid (which can be placed within a rigid frame around the perimeter for stability) requiring no foam supports. An additional advantage is that the depth of the grid is reduced by a factor of two.
[0137] Yet another technique involves using appropriately corrugated absorbing strips (with corrugations focused on the focal spot of the X-ray source) that are tapered in two dimensions such that the corrugations are focused on the X-ray source. These corrugated septa are then separated by planar septa. This technique is well known in the construction of collimators for nuclear medicine gamma cameras.
[0138] Other techniques used in nuclear medicine collimator construction such as casting can also be employed to obtain high-transparency, coarse scatter-rejection grids.
[0139] Scatter Reduction Using Source Collimation
[0140] The larger the extent of the irradiated portion of the object, the greater the scatter from the object. It is highly desirable from the viewpoints of both reducing patient dose and scattered X-rays that the source only irradiates the necessary portion of the object. In conventional radiography systems this is accomplished by using an adjustable source collimator to restrict the radiation field to the desired region of the object. As noted above, the system described here can use a detector having a width smaller than necessary for acquisition of a complete tomographic dataset. When used in conjunction with a source collimator that only irradiates the portion of the object “seen” by the detector less Compton scatter will be generated (and detected) than in a system using a full-size detector.
[0141] As shown in FIGS. 2 and 3 the detector 30 , as it moves along its track 35 , is connected to the X-ray source collimator 28 through the control arm 24 that ensures that the source 26 only irradiates portions of the object that are visible to the detector 30 .
[0142] Correction for Residual Scatter
[0143] A significant fraction of photons will scatter multiple times within the object and many of these can pass the scatter-rejection grid 32 . To reduce the average effect of detected scatter on reconstructed images, it is desirable to employ a method that measures the distribution of residual scatter. Once the mean distribution has been estimated, it can be removed from the data.
[0144] The residual detected scatter can be measured by placing a series of beam-stops or shadow masks (i.e., shadow mask 36 ) between the X-ray source 26 and the object. In the absence of scatter, the shadow of the beam-stops on the detector 30 should record zero photons. Photons that scatter in the object and that pass the scatter rejecting grid 32 will, however, result in some signal in these regions that should have none. If the shadow mask 36 does not perturb the X-ray flux significantly, the signal in these shadow regions can be taken as an estimate of the residual scatter detected at these points. This method has been previously employed for removing scatter from conventional projection radiographs.
[0145] In contrast to the aforementioned method, which requires two scans—one with and without the shadow mask 36 , or two with the shadow mask 36 in different positions—it is possible to leave the shadow mask 36 in place during the entire scan, which has three desirable consequences. First, the x-ray flux remains unchanged between the scatter measurement and the measurement from which the scatter-free projection is estimated from since they are performed simultaneously. This feature simplifies the correction procedure.
[0146] Second, since the shadow mask 36 need not be moved, the overall design is simplified. Finally, since it is not necessary to expose the patient twice to obtain both the diagnostic information and a measure of the scattered radiation, the overall radiation dose to the patient is reduced.
[0147] There are a number of ways shadow masks can be designed to allow this, one example is shown in FIG. 8. In this case, the absorbing components of the mask 36 , such as an absorbing frame 37 and absorbing rods 39 , are slightly outside the desired field-of-view 46 (i.e., outside a clear, imaging aperture 41 ) but since scatter varies smoothly, the detector 30 “sees” approximately the same scatter at these points as it does within the desired region.
[0148] Referring to FIGS. 9 through 13, an outline of the procedure for scatter estimation and correction is given as follows:
[0149] 1. With the shadow mask 36 between the source assembly 18 and the detector assembly 16 and no object in place, a “blank scan” is taken to determine where the shadows of the mask 36 lie on the detector 30 .
[0150] 2. This data is then processed to make two digital masks. The first defines regions-of-interest (ROIs) slightly smaller than the actual shadows. These ROIs will be used to estimate the residual scatter (FIG. 9). The second defines regions larger than the shadows (FIG. 10). These regions will be used in the correction process for the diagnostic data (patient scan).
[0151] 3. The patient is placed in the tomograph system 10 and scanned with the shadow mask 36 in place (FIG. 11).
[0152] 4. Using the first mask, the scattered radiation is estimated by the values at each view angle or frame of the patient scan by the values in each frame at every non-zero mask position.
[0153] 5. The scatter at zero mask positions is then estimated using an interpolation scheme (FIG. 12). A variety of schemes can be used.
[0154] 6. The scattered information is either explicitly or implicitly (e.g., during the 3D image reconstruction process) subtracted from the patient scan. Using the second mask, information in the shadow regions of the patient scan is “restored” (i.e., as if there were no shadow mask present). The preferred method for restoring this information is to use a penalized, weighted least-squares or penalized maximum likelihood 3D image reconstruction where the mask determines regions of missing data. Alternatively, the information can be estimated on a frame-by-frame basis (shown in FIG. 13), which may, in some cases, be preferable because the amount of computation is significantly reduced.
[0155] As noted, there are not only a variety of masks that can be employed but also a variety of estimation/restoration/reconstruction scenarios that can be used.
[0156] Moving or “Dithering” Position of Detector to Reduce Effects of Detector Non-Uniformity
[0157] Detectors always have small spatial non-uniformities of response. Sometimes these can be calibrated out by acquiring a sequence of images with the X-ray source off in order to obtain the “dark signal” or pedestal and another set with the X-ray source on with no object in place (“blank scan”) for determining the response or gain of each pixel. Often, however, the signal from a pixel may vary unpredictably when scanning the object. If not taken into account, these signals tend to add coherently in a conventional fan- or cone-beam scanning geometry and will generate rings of higher or lower density in reconstructed images. The magnitude of the ring depends both on the magnitude of the detector defect and its spatial sharpness: sharp-edged defects will generate much larger artifacts than smooth-edged defects.
[0158] A way to “smooth” any detector defect is to move the detector 30 along its track 35 a small amount randomly between each frame. This would typically be accomplished by moving the detector 30 under motor control between frames a random—but known—amount corresponding to a maximum of roughly ±20 pixels.
[0159] The data acquired in such a fashion are then shifted in the computer 12 after each image frame is collected such that it appears as if the detector 30 as in a single position. Due to the random detector movement, non-uniformities that previously added coherently to produce disturbing visual distortions in the reconstructed images now do not significantly affect reconstructions.
[0160] In cone-beam scanning, the more complete orbits described above (i.e., helical and wobbled) further reduce the effect of isolated detector artifacts.
[0161] Detector Masking for Pedestal Estimation During Scanning
[0162] With the area detector 30 , the pedestal or “dark signal” can vary considerably during the scan due to sensitivity of the readout electronics, which are proximal to the detector panel, to small variations in temperature. In ordinary radiography, these pedestal changes present little problem. In computed tomography, however, the changes may be larger than the signal of interest and it is therefore important that they be estimated throughout the scanning interval so that their effects can be removed either during or after the scanning. The varying pedestals in these devices are largely due to the readout amplifiers for each channel. In a device currently in use, each amplifier reads out a column of 256 channels (pixels) with half placed at the bottom edge and the remainder at the top edge of the detector (the detector has an array of 512×512 pixels). If the temperature of the readout chip changes, the offsets are changed for every pixel the amplifier reads out (e.g., an entire column).
[0163] Referring now to FIGS. 14 a - 14 c , the detector 30 is shown with gate driver ASICs 61 and readout ASICs 63 . In order to estimate pedestals during scanning without acquiring frames when the X-ray source 26 is off (which extends the overall scanning time), portions of the detector 30 adjacent to the integrated circuits containing the readout amplifiers are covered with an X-ray absorbing material 60 (i.e., FIG. 14 c ). The material 60 covers positions of a scintillator layer 62 . Alternatively, the photodiodes on the flat-panel 30 can be masked from light. Although this reduces the active area of the detector 30 slightly, the change in pedestal during the scan for each readout channel can be estimated from the change in the signal observed for the masked channels.
[0164] There are numerous methods for estimating the pedestal of each channel from the masked-channel information; the simplest assumes that the change in pedestal for each readout channel is the same for each detector element using a particular readout amplifier (i.e., a row or column of the array depending on orientation) and corrects each digitized detector value by the same digital pedestal change.
[0165] An alternative means for accomplishing this without detector masking—assuming the electronics of the detector 30 can be modified—is to have one or several electrical channels on each chip containing readout amplifiers not connected to the array (i.e., everything is similar to active channels but there is no possibility of a signal). These dark channels can then serve as estimates for the change in pedestal for each readout chip during scanning.
[0166] Generating Panoramic Images or “Conventional Tomograms” from Reconstructed CT Data
[0167] Once the 3D volume of attenuation coefficients have been reconstructed from the projection data, the information can be reprojected so that it emulates that acquired using other, more conventional devices such as panoramic X-ray machines or conventional linear tomographs used in dentomaxillofacial imaging. This is useful both for comparing data acquired with the system 10 to previous patient scans and for providing a simple method for “volume rendering” or summarizing the 3D volumetric data in a format familiar to the clinician.
[0168] Generating the scans corresponding to those acquired using more conventional devices is summarized by the following procedure:
[0169] 1. 3D patient data is acquired and reconstructed using the system 10 . The result is a volume of linear attenuation coefficients at a particular energy.
[0170] 2. A linear system model describing how a panoramic X-ray machine or linear tomography generates images from an object is used to map the reconstructed image volume into projections that would have been acquired using a conventional system. This provides the sum of linear attenuation along source-detector paths collected in the conventional instrument.
[0171] 3. This information is multiplied by −1 and exponentiated to provide the X-ray attenuation the conventional system would have observed. The information can then be displayed digitally or printed on paper or film for presentation.
[0172] The key to the above procedure is the system model describing the imaging characteristics (geometry, etc.) for each panoramic system or linear tomography. These linear models can be constructed using methods well known to developers of computed tomography software.
[0173] A system constructed in accordance with the present invention may include one or more of the following:
[0174] A vertically oriented cone-beam imaging system 10 capable of motions that allow a complete set of tomographic data to be acquired. This is accomplished by not only rotating the gantry 20 but by also allowing it to either pivot on an axis 53 orthogonal to the main rotation axis 51 or by moving the source assembly 18 and detector assembly 16 vertically, parallel to the main axis 51 of rotation during the scan such that the cone-beam completeness conditions are satisfied.
[0175] A tomographic system 10 capable of acquiring a complete CT scan with high and isotropic spatial resolution for the dentomaxillofacial complex that additionally is capable of performing both single- and dual-kV (“dual energy”) imaging.
[0176] The proposed scatter elimination technique using a coarse, high-transparency grid 32 (or crossed coarse grids) as opposed to fine granularity, relatively low-transparency grids.
[0177] The shadow mask 36 containing both absorbing elements for scatter estimation and spatially varying filtration for dual-energy imaging for the purpose of correcting beam-hardening artifacts.
[0178] The use of a shadow mask 36 that can be left in place during the diagnostic scan and methods for estimating the residual scatter and reconstructing the resulting data.
[0179] The use of a low current scout scan to determine the appropriate detector offset in addition to estimating appropriate exposure time (appropriate exposures are presently estimated using a scout scan).
[0180] The use of a detector that is smaller than necessary in conjunction with apparatus for moving the detector 30 relative to the source 26 and an appropriate X-ray collimator 28 to improve the precision of measurements by reducing scatter and by measuring some portions of the object twice relative to others.
[0181] Adapting the measurement system (X-ray collimation and detector position) dynamically to the size of the object to accomplish the above objectives (i.e., appropriate detector position for each frame is not estimated from scout scan but rather from previous frames).
[0182] Estimating the pedestal (or dark signal) for each channel that does not require turning off the X-ray source 26 or acquiring additional “blank” frames between X-ray exposures.
[0183] “Dithering” the position of the detector 30 in order to reduce visually disturbing artifacts.
[0184] Generating “panoramic” or conventional linear tomography images from the reconstructed CT volume.
[0185] Working Models and Simulations
[0186] Extensive simulations and a lab-bench prototype model have been constructed and used for imaging phantoms and cadaver heads in order to assess the utility of the system 10 in treatment planning for-dental implants. The spatial resolution of the system 10 is approximately 400 microns FWHM in all three spatial dimensions. Moreover, complete data is acquired and both single-and dual-energy scanning have been accomplished. This is in contrast to conventional spiral CT where spatial resolution is closer to 1 mm in the transaxial direction and 1.5-2 mm in the axial direction. Four tomographic slices of a human head are shown in FIGS. 15 a - 15 d.
[0187] It is certainly possible to construct a small X-ray CT scanner for imaging the head, neck and extremities in a variety of ways. For example, one can attach a large enough amorphous silicon detector to a rotating gantry and use no additional scatter correction hardware or software and obtain images that may be adequate for planning dental implants in many cases. Nevertheless, when it is desirable to be more quantitative to accurately assess bone quality, for instance, many of the features described above such as dual-energy imaging, scatter correction, and pedestal estimation methods will prove important.
[0188] It is also possible to use detectors other than amorphous silicon imaging arrays. For example, image intensifiers and CCD cameras can be and have been used (TomCAT). Nevertheless, simple devices based on these detectors still suffer problems such as scatter, detector size issues, tomographic completeness problems, etc. The methods described above are solutions to those common problems and most do not depend on the type of detector used.
[0189] While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. | A high spatial resolution X-ray computed tomography (CT) system is provided. The system includes a support structure including a gantry mounted to rotate about a vertical axis of rotation. The system further includes a first assembly including an X-ray source mounted on the gantry to rotate therewith for generating a cone X-ray beam and a second assembly including a planar X-ray detector mounted on the gantry to rotate therewith. The detector is spaced from the source on the gantry for enabling a human or other animal body part to be interposed therebetween so as to be scanned by the X-ray beam to obtain a complete CT scan and generating output data representative thereof. The output data is a two-dimensional electronic representation of an area of the detector on which an X-ray beam impinges. A data processor processes the output data to obtain an image of the body part. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for controlling the temperature of oil maintained in an overhead tank. More specifically the invention concerns rerouting oil being supplied to the seals of a turbomachine to direct a portion of the oil through an overhead tank to maintain the overhead tank oil temperature at a desired level.
Large turbomachines utilize oil seals which prevent gases from escaping along the shaft ends to the environment. Typically these seals are provided with an oil supply system which supplies clean oil under pressure to the seals and receives contaminated oil from the seals. The oil delivery system typically includes a console which acts to supply oil under pressure and receives the discharged oil from the compressor. The console acts to clean and/or filter the oil, to increase or reduce its temperature, to remove pollutants therefrom by various processes and to otherwise condition the oil such that it may be resupplied to the turbomachine under pressure.
Seals used on large turbomachines do require oil for cooling and sealing. The interruption of the flow of oil for sealing purposes results in catastrophic failures. It is known to provide a back-up oil delivery system for maintaining oil flow under pressure to the seals in the event of failure of the oil supply system. It is further known to mount an overhead tank at a desired height containing oil to establish the proper seal differential pressure such that oil may be supplied from the tank to the seals under pressure to provide the necessary sealing on an interim basis.
The overhead tank is located at a height sufficiently above the turbomachine that a static pressure head is created therebetween such that the oil at the desired pressure may be supplied from the tank. The desired pressure level is required since oil must be maintained at a pressure slightly above the gas pressure to prevent leakage of the gas.
In certain plant layouts the overhead tank is mounted quite a distance from the turbomachine and often in an ambient of significantly different temperature conditions. Under these circumstances since the oil in the tank tends to be stagnant except when the tank is being filled or in an emergency situation requiring emptying of the tank, the oil in the tank tends to reach the ambient temperature condition. Should the oil in the tank be much cooler than the desired oil supply temperature, then the viscosity of the oil changes and the volume flow of the oil through the supply lines to the turbomachine may be reduced such that an emergency supply of oil is not provided when necessary. Again should oil of much lower viscosity be supplied thereto the volume flow of oil through the seals will be significantly reduced and the seals may be starved causing damage to the seals and effectively preventing the back-up emergency oil supply system from accomplishing its desired sealing function.
The solution proposed to the problem of the temperature of the oil in the tank not being at the desired operating temperature includes routing a portion of the oil being supplied to the turbomachine through the tank such that the oil in the tank is maintained at the desired operating temperature rather than the ambient temperature of the region where the tank is located. A specific supply system including level sensors and control valve for diverting a portion of the flow of sealing oil to the tank is set forth herein.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide apparatus for adequately supplying oil to a turbomachine from a tank when conditions warrant.
It is a further object of the present invention to provide a back-up supply of oil for servicing seals of a turbomachine should the normal oil supply fail for any reason.
It is a still further object of the present invention to provide a method and apparatus for maintaining the temperature of the oil in an overhead oil tank at a desired temperature level without regard to the ambient temperature in the region surrounding the overhead tank.
It is a yet further object of the present invention to provide a control means and method for allowing a portion of the oil being supplied to the seals of a turbomachine to be routed through an overhead tank for maintaining the temperaure of the tank while simultaneously maintaining the static head pressure differential between the tank and the seals to allow the tank to serve the appropriate back-up oil supply function.
It is a still further object of the present invention to provide a reliable, cost effective and easily maintainable system for maintaining the temperature of oil in an overhead tank at a desired level.
Other objects will be apparent from the description to follow and the appended claims.
The above objects are achieved according to a preferred embodiment of the invention by providing an oil delivery system for supplying oil to a portion of the turbomachine having a pressurized fluid flowing therethrough. The oil delivery system includes an oil supply means for supplying oil under pressure to the turbomachine and for receiving oil from the turbomachine. A first conduit connecting an oil supply means to the turbomachine, and a second conduit connecting the turbomachine to the oil supply means are further included. A tank which is at least partially filled with oil is connected to the first conduit via a discharge line. The tank is mounted at an elevation sufficiently above the turbomachine that oil may be routed from the tank through the discharge line and the first conduit to the turbomachine at a pressure higher than the pressure of the fluid received by the turbomachine. Additionally means for altering the temperature of the oil in the tank to approximate the operating temperature of the oil in the oil delivery system are included.
Additionally disclosed is a method of maintaining a reliable alternate source of oil using a tank positioned vertically above a turbomachine while maintaining the desired relative pressure of the oil supplied from the tank, said tank being a portion of an oil delivery system for supplying oil for sealing purposes to the turbomachine and including an oil supply means for supplying oil under pressure and for receiving oil, first conduit means for conducting oil from the oil supply means to the turbomachine, second conduit means for conducting oil from the turbomachine to the oil supply means and a discharge line connecting the tank to the first conduit means, and including the step of regulating the temperature of the oil in the tank to maintain the desired oil flow characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a prior art oil delivery system.
FIG. 2 is a schematic drawing of the herein described improved oil delivery system.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Apparatus as described herein will refer to a oil delivery system used with a compressor for increasing the temperature and pressure of a fluid. It is to be understood that this oil delivery system has applicability to other types of turbomachinery in addition to compressors. It is further to be understood that although the oil delivery system as shown herein is used to direct oil to the seals of the compressor that the oil delivery system may be used for other purposes such as maintaining bearing lubrication pressures and may be used in conjunction with other equipment.
FIG. 1 is a schematic drawing of a prior art oil delivery system. Oil is supplied at the appropriate temperature and pressure and in the appropriate state of cleanliness from oil console 120 to line 122. Oil flows through line 122, through level control valve 154, through line 126, through check valve 124, and through line 135 to line 138 and therefrom to seals 116 and 118 of compressor 110. Oil flows through the seals and then through return lines 140 from seals 116 and 118 to return line 142 back to oil console 120.
In addition oil flows from line 135 to line 136 to tank 130. A sufficient quantity of oil is maintained in the tank to at least partially fill tank 130. Level control sensor 152 is mounted to the side of tank 130 and is positioned to detect the level of oil within the tank. Level control valve 154 is controlled by level controller 152 and acts to regulate the volume flow of oil through line 126. When level controller 152 senses the oil level in tank 130 is too low, it acts to open level control valve 154 such that additional oil is supplied through line 126. Since the seal clearances within seals 116 and 118 allow only a desired flow of oil therethrough the additional oil flow supplied through line 126 is routed through line 136 to tank 130 causing the oil level in the tank to increase. Level controller 152 acts in the opposite manner when the oil level is too high such that the level control valve 154 is closed and a portion of the oil flowing to the seals is then supplied from tank 130 as well as the remainder of the oil being supplied from oil console 120.
Check valve 124 is positioned in line 126 such that oil flow from tank 130 may not flow to oil console 120 but instead must flow to a compressor 110.
Compressor 110 receives fluid through inlet 112 and discharges that fluid through outlet 114. Typically the fluid being discharged is at a higher temperature and lower pressure than when it was received. Balancing line 160 is connected between inlet 112 and tank 130 such that the pressure of the gas at the top of tank 130 is maintained at an equivalent level to the pressure of the fluid entering the compressor.
Tank 130 is utilized to provide a supply of oil under pressure should oil console 120 fail for some reason. In the event of a power outage such that oil console 120 did not act to supply oil under pressure then oil contained in tank 130 would be utilized to supply lubricant under pressure to seals 116 and 118. Once the oil console 120 shuts down the oil contained in tank 130 flows through line 136, through line 135, and through line 138 to the seals. The mere failure of flow from the oil console is sufficient to allow the oil to flow from the tank to supply the desired amount of oil to the seals.
FIG. 2 is a schematic drawing of the improved oil delivery system wherein the temperature of the oil within the overhead tank is maintained at the desired level. In FIG. 2 the reference numerals correspond to the numerals of FIG. 1 with the omission of the first digit. In FIG. 2 it may be seen that oil is supplied from oil console 20 through line 22, through check valve 24, through line 26, through level control valve 54, and through line 35 to lines 38 supplying seals 16 and 18 of compressor 10. Once discharged from the seals discharged oil flows through line 40 to line 42 and back to the oil console to complete the circuit. Compressor 10 is shown having inlet 12 and outlet 14 for discharging the working fluid.
Tank 30 is shown positioned vertically above the compressor a distance h and is connected via discharge line 36 to line 35 and via supply means including line 26, pressure restriction device or orifice 28, and supply line 32. Level controller 52 is shown for sensing the level of the oil in the tank and is shown connected to level control valve 54. In addition level controller 52 causes block valve 80 to close on a high oil level being detected indicating that further oil being supplied to the tank may overfill the tank. Balancing line 60 is shown extending from the inlet to the compressor to tank 30. Additionally pressure sensor 66 is shown to sense the pressure difference between the fluid in the balancing line 60 versus the oil being supplied via oil console 20 to the compressor bearings. Lines 64 and 62 are shown connecting pressure sensor 66 to balancing line 60 and supply line 35, respectively.
Pressure sensor 66 is used to determine the pressure differential of the oil being supplied to the seals relative to the pressure of the gas entering the compressor.
Typically the temperature of the oil being discharged from the oil console will be higher than the temperature of the oil maintained in the overhead tank since the overhead tank may be mounted in ambient air of significantly lower temperatures and since the oil being circulated through the compressor seals is heated by the compressor. As shown in FIG. 2, oil being discharged from the oil control passes through check valve 24 and then a portion thereof may flow through line 26 and through orifice 28 and valve 80 to tank 30. Since it is desired to maintain the level of the tank at a preselected height the equivalent amount of oil flowing into the tank is discharged from the tank through line 36 to be supplied to the seals. Level control valve 54 is positioned to divide the flow being discharged from the oil console such that a small portion of the oil flow flows through the supply line as restricted by orifice 28 to the tank and the bulk of the oil flow passed directly to the compressor seals. An equivalent amount of oil as the oil being supplied through the supply line to the tank flows from the tank out the discharge line 36 to the compressor. Check valve 24 is maintained upstream from the supply line to the tank such that in the event of oil console failure oil will not flow from the tank to the oil console but will in turn be directed as desired to the compressor seals. The oil flowing through the supply line to the tank mixes with the oil in the tank such that the oil in the tank is maintained near the temperature of the oil being supplied thereto. By this manner should a failure occur the oil from the oil tank being supplied to the seals will be at the same temperature and pressure as the oil being supplied from the oil console such that an appropriate amount of oil will be available to the seals to provide the desired sealing effect. Since the amount of oil flow through the supply line into the tank and from the discharge line from the overhead tank to maintain the tank at this desired temperature level is small, the desired static pressure difference provided by the height difference between the tank and the compressor is maintained while allowing for the small amount of flow. Should a large flow be required then it would be difficult to maintain this desired static pressure difference.
The invention has been described with reference to a particular embodiment. It is to be understood by those skilled in the art that variations and modifications can be effected within the spirit and scope of the invention. | An oil delivery system for supplying oil to seal a portion of a turbomachine is disclosed. Specific means for routing oil at a desired temperature to an overhead tank are disclosed such that should oil from the overhead tank be required, as in an emergency or shutdown condition, then the oil being supplied from the tank will be at or near the temperature of the oil being supplied during normal operating conditions. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority from U.S. Provisional Patent Application Ser. No. 60/371,436, filed Apr. 10, 2002, entitled “Minimal Preference Elicitation In Combinatorial Auctions”.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to auctions and, more particularly, to winner determination in forward auctions, reverse auctions and exchanges.
2. Description of Related Art
Combinatorial auctions where bidders can bid on bundles of items can be desirable market mechanisms when the items exhibit complementarily or substitutability, so the bidder's valuations for bundles are not additive. One of the problems with these otherwise desirable mechanisms is that determining the winners is computationally complex. There has been a recent surge of interest in winner determination algorithms for such markets.
Another problem, which has received less attention, is that combinatorial auctions require potentially every bundle to be bid on, and there are exponentially many bundles. This is complex because a bidder may need to invest considerable effort or computation into determining each valuation. It can also be undesirable from the perspective of revealing unnecessary private information and from the perspective of unnecessary communication.
It is, therefore, desirable to identify a topological structure that is inherent in combinatorial auctions that can be used to intelligently ask only relevant questions about the bidders' preferences while still finding the optimal (welfare-maximizing and/or Pareto-efficient) solution(s). It is also desirable to provide building blocks for a design of an auctioneer that interrogates each bidder intelligently regarding the bidder's preferences, and optimally assimilates the returned information in order to narrow down the set of potentially desirable allocations, and decide which questions to ask the bidders next to further narrow down the set of potentially desirable allocations.
SUMMARY OF THE INVENTION
The invention is a method of determining a winning allocation in a forward auction, reverse auction or an exchange that includes: (a) defining a plurality of allocations, wherein each allocation defines a trade between one or more potential buyers and one or more potential sellers; (b) querying at least one potential buyer regarding at least one preference of said buyer about at least one allocation or a bundle associated therewith; (c) receiving said buyer's reply or intimation to the query; (d) based on said reply or intimation, eliminating from consideration as a winning allocation each allocation that is at least one of (1) not feasible and (2) not optimal; and (e) based on a predetermined criteria, selecting one of the remaining allocations as the winning allocation.
The method can further include, before step (e), repeating steps (b-d) a plurality of times. For each repetition of step (b), a different buyer can be queried from the previous repetition of step of (b).
The reply in step (c) can be responsive to the query or unsolicited information regarding the at least one preference of the buyer. The intimation in step (c) can be the absence of a response by the buyer to the query.
The predetermined criteria can include: one remaining allocation; all remaining allocations are equally optimal; the remaining allocation's values are all within a measure of each other; and all remaining allocations have values that are within a predetermined range of values. The measure can include a bound or a factor.
The query can include at least one of: the bidder's desired price for a bundle; the bidder's desired ranking of a bundle; the bidder's desired order of at least two bundles in the sense the buyer prefers one bundle over another; the bidder's desired bundle when a hypothetical bid price is proposed for two or more bundles; the bidder's desired attribute(s) associated with a bundle or at least one item thereof; and how the bidder assimilates attribute(s) in the sense of how his utility is affected by the attribute values.
The attribute(s) can include at least one of at least one of credit history, shipping cost, bidder credit worthiness, bidder business location, bidder business size, bidder zip code, bidder reliability, bidder reputation, bidder timeliness, freight terms and conditions, insurance terms and conditions, bidder distance, bidder flexibility, size, color, weight, delivery date, width, height, purity, concentration, pH, brand, hue, intensity, saturation, shade, reflectance, origin, destination, volume, earliest pickup time, latest pickup time, earliest drop-off time, latest drop-off time, production facility, packaging and flexibility.
The bidders desired price can include one of an exact price, an upper bound and a lower bound.
The query can include the bidder being asked if a valuation for a bundle is an exact price and/or the bidder being asked to supply an exact price for the bundle. The query can also include the bidder being asked to supply a ranking of at least two bundles; the bidder being asked to supply a bundle that the bidder desires at a specific ranking; the bidder being asked to supply a desired ranking to a bundle X; and/or the bidder being asked to supply a next desired bundle after a bundle X.
Each bundle includes at least one item, a quantity of the one item and a price for the bundle.
The values of the bundles forming the winning allocation, absent the value of each bundle of one bidder, can be summed to obtain a first value. Another winning allocation can then be determined absent the one bidder. The values of the bundles in the other winning allocation can be summed to obtain a second value. A difference between the first and second values can be determined and said difference can be assigned as the value of each bundle of the one bidder in the winning allocation regardless of the price assigned to each bundle of the one bidder by the one bidder. The thus assigned difference is the value the one bidder pays or the value the one bidder receives for the bundle.
The query can elicit from the buyer information only known be the buyer.
The query can include the bidder being asked the effect on at least one offer if the allocations are restricted and/or the bidder being asked what restriction can be applied to the allocations to produce a specific change in at least one offer. The query can further include the bidder being asked how much of a discount will an offer receive for a minimum value commitment and/or the bidder being asked how much business will the bidder have to be given in order to get from the bidder a predetermined percentage discount.
Any one or more of the foregoing method steps can be embodied in instructions which are stored on computer readable medium. When these instructions are executed by a processor, the instructions can cause the processor to perform any one or combination of the foregoing method steps.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is the rank lattice of the possible combination of bids of two bidders wherein infeasible allocations are illustrated on a highlighted background;
FIG. 2 is the rank lattice of FIG. 1 with bids that are dominated by feasible collections shown on a highlighted background;
FIG. 3 is a spread-sheet showing bid prices bid by each bidder in connection with the various bids of the rank lattice shown in FIGS. 1 and 2 ;
FIG. 4 is an overlay combination of the rank lattices shown in FIGS. 1 and 2 including for some of the combination of bids of bidders 1 and 2 the sum of the bid values; and
FIG. 5 is an augmented order graph that includes a node for each bidder—bundle pair and which further includes the rank lattice of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in connection with a combinatorial forward auction. However, this is not to be construed as limiting the invention since the present invention is also applicable to combinatorial reverse auctions and combinatorial exchanges.
The present invention will also be described with reference to the accompanying figures and to the following list of symbols and their meanings which are used herein to describe the invention. While most of the listed symbols are used consistently throughout the following detailed description, the meaning of some of the symbols may change depending upon the context in which they are used—which change in context would be apparent to one of ordinary skill in the art to which the invention pertains. Therefore, it is to be understood that each of the following listed symbols and their meanings are provided to facilitate an understanding of the invention and the manner and process of making and using the it, in such full clear, concise and exact terms to enable one skilled in the art to make and use the same and are not to be construed as limiting the invention.
bundle = subset of items
i = subset of I or bidder i
C = set of rank vectors
j = bidder j
C ab = value domination
K = subset of vertices in
c = node c (in rank lattice)
augmented order graph G
edge(s) = arc(s) in G
k = node k
G = augmented order graph
l = node l
I = newly received information
m = number of items
N = set of bidders {1, . . . , n}
z = allocation or welfare
n = node n, node in a rank lattice
maximizing allocation
dominated by node c, or a number of
Ω = set of indivisible,
bidders
distinguishable items
O ab = order domination
ω 1 , ω 2 . . . , ω m
R = rank vector or rank of a node
⊂ = is a subset of
r = rank vector
∪ = union
s = start node
∩ = intersection
r = successor bundles (from S) in the
⊂ = is a proper subset of
rank lattice
∈ = is an element of
= set of vertices in augmented order graph
∉ = is not an element of
v i = value bidder i is willing to pay
∃ = there exists
for a given bundle
∀ = for every
v j = value bidder j is willing to pay
> = domination arc (indicates
for a given bundle
that one bid dominates
x = bundle
another bid)
x = bundle x
\ = does not include
x i = bundle of a bundle
s.t. or : = such that
Y = input set of rank vectors
| | = absolute value
Y i = bundle of i
y = bundle y
In a combinatorial auction, a seller has a set Ω={ω 1 , . . . , ω m } of indivisible, distinguishable items for sale. Any subset of the items is called a bundle. The set of bidders (buyers) is called N={1, . . . , n}.
Herein, it is assumed that the seller has zero reservation prices on all bundles, i.e., the seller gets no value from keeping them. If in reality the seller has reservation prices on bundles, that can be modeled by treating the seller as one of the bidders who submits bids that correspond to the reservation values. Each bidder has a value v i that the bidder is willing to pay for any given bundle. It is assumed that the valuations v are unique (v i (X)≠v j (Y) if i≠j or X≠Y). This an innocuous assumption since if the valuations are drawn from real numbers the probability of a tie is zero.
In accordance with the present invention, the auctioneer can ask any bidder i questions about the bidder's valuation v i , and it is assumed that the bidder answers each question truthfully.
Initially, a standard quasilinearity assumption about the bidder's utilities is made. Namely, the utility u of any bidder i for a bundle A ⊂ Ω is u i (A, p)=u i (A)−p, where p is the amount that the bidder has to pay.
A collection (X 1 , . . ., X n ) states which bundle X i ⊂ Ω each bidder i receives. In a collection, some bidders' bundles may overlap in items, which would make the collection infeasible. A collection is called an allocation if it is feasible, i.e., each item, or each unit of an item having multiple units in the auction, is allocated to at most one bidder. The possibility that X i =0 is allowed.
An allocation X is welfare maximizing if it maximizes
∑ i = 1 n v i ( X i )
among all allocations (feasible collections). An allocation X is Pareto efficient if there is no other allocation Y such that v i (X i )≧v i (Y i ) for each bidder i and strictly for at least some bidder i. As used herein, Pareto efficiency is based on comparison of bundles within an agent, or bidder. If payments are taken into account in the definition of Pareto efficiency, then the set of Pareto-efficient solutions collapses to equal the set of welfare-maximizing solutions.
Topological Structure in Combinatorial Auctions
There is significant topological structure in the combinatorial auction setting. This topological structure is utilized hereinafter to avoid asking the bidders unnecessary questions about their valuations.
Rank Lattice and Associated Algorithms
With reference to FIGS. 1 and 2 , conceptually, bundles can be ranked for each agent, or bidder, from most preferred to least preferred. This gives a unique rank for each bundle for each agent, or bidder. Without reference to the values of the bundles, each collection can be mapped to a unique rank vector [R 1 (X 1 ), R 2 (X 2 ), . . . , R n (X n )]. The set of rank vectors, and a “dominates” relation between them define a rank lattice of the type shown in FIG. 1 . A “dominates” relation is defined as: given two rank vectors a and b, a dominates b iff a i ≧b i for all bidders i and a j >b j for at least one bidder j. If a collection (resp. its rank vector) is feasible (i.e., is an allocation), then no collection (resp. its rank vector) “below” it in the rank vector can be a better solution to the allocation problem.
For example, suppose there are two goods, A and B, and two agents, or bidders, a 1 and a 2 . The agents, or bidders, rank the bundles as follows:
Agent (bidder) a 1 : (1:AB, 2:A, 3:B, 4:0) Agent (bidder) a 2 : (1:AB, 2:B, 3:A, 4:0)
This implies the rank lattice of FIG. 1 . Only the subset of the collections not highlighted in FIG. 1 is feasible and, thus, correspond to allocations. In the rank lattice of FIG. 1 , the nodes are collections. Some of the collections are dominated, as shown in highlight FIG. 2 , some are infeasible, as shown in highlight in FIG. 1 , some are both, e.g., collections [ 2 , 3 ] and [ 3 , 2 ] and some are neither, i.e., collections [ 1 , 4 ], [ 2 , 2 ] and [ 4 , 1 ].
If a feasible collection is not dominated by another feasible collection, it belongs to the set of Pareto-efficient solutions. As shown in FIG. 4 , by overlaying the rank lattices of FIGS. 1 and 2 , it can be seen that the set of Pareto-efficient solutions is [ 2 , 2 ], [ 1 , 4 ], [ 4 , 1 ].
The following Algorithm 1, that operates top-down, breadth-first along the implicitly given structure of the rank lattice, can be used to compute the set of Pareto-efficient allocations.
(Algorithm 1):
s = (1, . . ., 1) /* start node */
PAR = [] /* List of Pareto-optimal nodes */
OPEN = [s] /* List of unexpanded nodes */
while OPEN ≠ [] do
Remove(c, OPEN)
SUC = suc(c)
if Feasible (c) then
PAR = PAR ∪ {c}
Remove(SUC, OPEN)
else for each n ∈ SUC do
if n ∉ OPEN and Undominated (n, PAR)
then Append(n, OPEN)
For computational purposes, successor function suc(c) can be implemented by deriving from a node c its set of successors (r 1 , . . . , r n ) as follows. For each i, 1≦i≦n with r i <2 m , generate s i ∈suc (c) as s (r 1 , . . . , r i +1, . . . , r n ).
In each cycle of step Remove(c, OPEN) in Algorithm 1, at least one node is removed from the list of open nodes. No node will be appended twice to the list of open nodes. To see this, note that the rank lattice is explored level-wise, that is, nodes of a level n+1 are only added, while nodes of the level n are explored. This ensures that a node that is removed from the head of the list OPEN will not be added again. Nodes that are removed because they have a feasible parent node will not be added again, because a node is only appended to the list OPEN if it is neither contained in the list OPEN nor if it is dominated by a node in the list PAR. A node that has been removed is dominated by a node in the list PAR, and no other collection will ever be added to the list PAR.
With the assumed finiteness of the preference orders, termination follows.
Furthermore, every rank vector representing an infeasible collection of bundles that is not dominated by a rank vector which represents an allocation, will be expanded. Thus, assuming the correctness of the feasibility check, every feasible collection (allocation) that is not dominated by another feasible collection (allocation) will be found and added to the list PAR.
If (monetary) valuations of preferences are available, the rank lattice can be utilized to guide the search for a welfare-maximizing solution. For example, let there be the two goods, A and B, and the two agents, or bidders, a 1 , and a 2 of the above example wherein the agents, or bidders, assign values to the bundles as shown in FIG. 3 . The values shown in FIG. 3 imply the preference order previously considered. The value-augmented rank lattice is shown in FIG. 4 . The welfare-maximizing allocation is given by rank vector [ 2 , 2 ], that is X*={A, B}.
The following Algorithm 2 uses rank and value information to determine a welfare-maximizing allocation.
(Algorithm 2):
s = (1, . . .,1) /* start node */
OPEN = {s}; /* List of unexpanded nodes */
CLOSED = 0; /* List of expanded nodes */
while OPEN = 0 do
c = arg mac c∈OPEN Σ i∈ N v i (c i )
OPEN = OPEN \ {c}
if Feasible(c) then return {c}
CLOSED = CLOSED ∪{c}
SUC = suc(c)
for each n ∈ SUC do
if n ∉ OPEN and n ∉ CLOSED
then OPEN = OPEN ∪{n}
In practice, Algorithm 2 prompts the auctioneer to ask one or more agents, or bidders, questions to determine the best rank vector in the list OPEN (i.e., to solve arg max). In response to receiving the rank information, the auctioneer would input this information into Algorithm 2 for processing. More specifically, Algorithm 2 traverses the rank lattice in a way that leads to a natural sequence of questions for the auctioneer to ask the one or more bidders, e.g., asking for each bidder their highest ranking bundle first, then proceeding to the next best bundle and so on.
Additionally or alternatively, the auctioneer can ask each bidder the following question which is more natural than an unconstrained rank question: “if you cannot get any one of the bundles that you have named desirable so far, what is your next preferred bundle?”
Algorithms 1 and 2 are based on a search, with the search strategy imposing constraints on the order in which questions are asked. Hereinafter disclosed is an additional data structure that can be used to avoid this problem. Questions can be asked in any order that the auctioneer considers (ex ante) most efficient, and no unnecessary (from the perspective of all the information known and derivable at that time) questions are asked.
Augmented Order Graph
With reference to FIG. 5 , an augmented order graph G of the goods, or items, and agents, or bidders, shown in Example 1 includes a node for each (bidder, bundle) pair (i, X). It includes a directed arc, e.g., arc A, from node (i, X) to node (i, Y) of the same bidder whenever v i (X)>v i (Y). These arcs are called domination arcs >. Graph G also includes an upper bound value UB and a lower bound value LB for each node. Finally, it includes a rank R i (X) for every node. Because there may be nodes of bidder i that are not joined with an arc, and rank values may be missing, some of these variables may not have values.
Initially, graph G includes no edges. Upper bounds UBs are initialized to ∞, or a very large number, and lower bounds LBs are initialized to 0 in the free-disposal case or to −∞, or a very large negative number, in the general case. All of the rank information is initially missing. If there is free disposal, edges, e.g., edge E, are added to graph G to represent the absence of rank information when ((i, X), (i, Y))∈>iff Y⊂X and X≠Y.
The augmented order graph G of FIG. 5 shows the 2-agent, or bidder, 2-good example discussed above at a stage where some of the information from the bidders has not yet been asked or elicited. In the upper right corner of FIG. 5 , two allocations and their relation to the nodes in graph G are shown. These allocations are connected to the corresponding feasible allocations in the rank lattice. The lower bound value LB of an allocation is the sum of the lower bound values of the bundles in that allocation. Similarly, the upper bound value UB of an allocation is the sum of the upper bound values of the bundles in that allocation. In FIG. 5 , the allocations can be ordered due to previously obtained available rank information. As shown in the upper right hand corner of FIG. 5 , allocation ({A}, {B}) dominates allocation ({0}, {B}). The rank vector highlighted in FIG. 5 represents the welfare-maximizing allocation. This, however, cannot be determined yet due to lack of information.
In accordance with the present invention, augmented order graph G can be utilized as a basic analysis tool. As new information is obtained, it is incorporated into augmented order graph G. This may cause new arcs or edges to be added, bounds to be updated, or rank information to be filled in. As a piece of information is obtained and incorporated, its implications are fully propagated, as will be discussed hereinafter. The process is monotonic in that new information allows us to make more specific inferences. Edges are never removed, upper bounds UBs never increase, lower bounds LBs never decrease, and rank information is never erased.
Policy-Independent Algorithms for Selecting Allocations
Next, algorithms, or sets of rules for solving problems, are disclosed that find desirable allocations based on asking the bidders questions. The idea is to use the algorithms as a means for guiding an auctioneer to intelligently ask bidders appropriate questions for determining good allocations without asking unnecessary questions. Each of the algorithms is incremental in that it requests information, propagates the implications of the answer, and does this again until it has received enough information. For example, the auctioneer may be able to ask any bidder i any of the following questions:
Order information:
Which bundle do you prefer, A or B?
Value information:
What is your valuation for bundle A? (The bidder
can answer with bounds or an exact value).
Rank information:
In your preferences, what is the rank of bundle A?
Which bundle has rank x in your preferences?
(Hereinafter discussed is the more natural question:
If you cannot get the bundles that you have declared
most desirable so far, what is your most desired
bundle among the remaining ones?)
In different settings, answering some of these questions might be more natural and easier than answering others. Therefore, different algorithms are disclosed that use only some of these types of questions. In the following description, mnemonic subscripts r, v and o refer to rank information, value information and order information, respectively.
General Structure and Common Routines
All of the policy-independent algorithms discussed hereinafter utilize the same general structure. Namely, augmented order graph G and an input set of rank vectors Y are expected as input to the algorithms. For some algorithms, the input set of rank vectors Y will include only feasible rank vectors, which represent allocations. For other algorithms infeasible rank vectors will also be considered.
A general, or generic, algorithm is shown in the following Algorithm 3:
(Algorithm 3):
Solve(Y, G):
while not Done (Y, G) do /* Algorithm Done is described hereinafter/
o = SelectOp(y, G) /* Choose question */
I = Perform Op(o, N) /* Ask a bidder the question */
G = Propagate (I, G) /* Update graph G */
U = Candidates (Y,G) /* Curtail the set of candidate allocations */
In addition to Algorithm 3 the following Algorithms 4-10 to compare two collections and to propagate value information, rank information and order information in augmented order graph G.
Given two collections, a and b, and augmented order graph G, the following Algorithm 4 can be used to check whether a dominates b. This is determined using a combination of value and order information (queried and inferred). Algorithm 4, i.e., the Dominates procedure, does not explicitly use rank information because the implications of the rank information will have already been propagated into the value information in the bounds and the order information.
(Algorithm 4):
Dominates(a, b, G):
O ab = FALSE /* Flag for order domination */
C ab = 0 /* Amount of value domination */
for each i ∈ N do
if LB i a > UB i b
then C ab = C ab + (LB i a − UB i b )
else if a i > bi
then O ab = TRUE
else C ab = C ab + (LB i a − UB i b )
if C ab > 0 or (C ab = 0 and 0 ab = TRUE)
then return TRUE else return FALSE.
If augmented order graph G is consistent, that is, order and value information are not contradictory, Algorithm 4 returns TRUE if and only if (iff) enough information has been queried to determine that a dominates b. Otherwise, FALSE is returned.
Next, the propagation of newly received information is disclosed. If value or order information is inserted into a previously consistent graph G, values of upper bounds UBs are propagated in the direction of the edges and lower bounds LBs in the opposite direction. This propagation is done via a depth-first-search (that marks the nodes touched when they are visited) in graph G, so the propagation time is O(v+e), where v is the number of bundles, i.e., the number of nodes in G that correspond to the agent, or bidder, whose values are getting updated, and e is the number of edges between those nodes. The insertion of rank information is performed as a sequence of insertions of new edges that reflect the derivable order information.
When searching augmented order graph G, the following algorithms can be utilized at a node k for inserting a new lower bound LB (Algorithm 5) inserting a new upper bound UB (Algorithm 6), inserting a new edge k>l (Algorithm 7), inserting an exact valuation for node k (Algorithm 8) and inserting a rank for node k (Algorithm 9).
(Algorithm 5):
PropLB (k, G) /* graph G contains the set of edges > */
Pre = {l : (l, k) ∈ > }
for each l ∈ Pre do
if LB k > LB l then LB l = LB k and PropLB(l, G)
(Algorithm 6):
PropUB(k, G)
Suc = {l: (k, l) ∈ > }
for each l ∈ Suc do
if UB k < UB l then UB l = UB k and PropUB (l, G)
(Algorithm 7):
InsertEdge((k, l), G)
if LB k < LB l then LB k = LB l and PropLB (k, G)
if UB k < UB l then UB l = UB k andPropUB (l, G).
(Algorithm 8):
Insert Value((k, v), G)
LB k = v
PropLB(k, G)
UB k = v
PropUB(k, G).
(Algorithm 9):
InsertRank((n, r), G)
(i, b) = n and K = {j, c) ∈ V: j = i}
if ∃k ∈ K with R k < R n and
R k ≧ R l ∀l ∈ K with R l < R n
then InsertEdge ((k, n), G)
if ∃k ∈ K with R k > R n and
R k ≦ R l ∀l ∈ K with R l > R n
then InsertEdge ((n, k), G).
Given a set of newly received information, I, and augmented order graph G, the following Algorithm 10 will insert information I and propagate it.
(Algorithm 10):
Propagate(I, G):
for each i ∈ I do
switch i /* Structural switch */
(node k, LB b):
if LB k < b then LB k = b; (Call Algorithm 5) PropLB(k, G)
(node k, UB b):
if UB k > b then UB k = b; (Call Algorithm 6) PropUB(k, G)
(node k, node l): (Call Algorithm 7) InsertEdge((k, l), G)
(node k, value v): (Call Algorithm 8) Insert Value((k, v), G)
(node k, rank r): (Call Algorithm 9) InsertRank((k, r), G)
As can be seen, based on the general structure of Algorithm 3, policy-independent algorithms, e.g., Algorithms 5-9, can be derived that differ on the types of information that they request from the bidders. To complete Algorithm 3, the procedures embodied in Algorithms 5-9 have to be plugged into Algorithm 3.
Algorithms that Query Value Information
Next, the querying of value information will be described. More specifically, the following Algorithms 11 and 12 are plugged into Algorithm 3 to determine the set of welfare-maximizing solutions.
Given a non-empty set of feasible allocations Y, and augmented order graph G, the following Algorithm 11 checks whether all the allocations in the set of feasible allocations Y have the same value.
(Algorithm 11):
Done v (Y, G):
if |Y| = 1 then return TRUE
for each a ∈ Y do
lb = Σ n∈G a LB n
ub = Σ n∈G a UB n
if lb ≠ ub then return FALSE
return TRUE.
Algorithm 11 returns TRUE if and only if all allocations in Y have the same value.
The following Algorithm 12 determines from a set of feasible allocations Y a subset a that contains all allocations that are not known to be dominated, given the information available in graph G. The resulting set will only contain allocations that are pairwise incomparable with respect to Algorithm 4. More specifically, Algorithm 12 determines the (maximal) set 0 of allocations such that for each allocation a in 0 there does not exist an allocation b in the input set Y which dominates a.
(Algorithm 12):
Candidates v (Y, G):
O = 0; C = 0
while Y ≠ 0 do
pick a ∈ Y /* arbitrarily selects an element */
Y = Y \{a}; C = 0
while Y ≠ 0 do
pick b ∈ Y; Y = Y\{b}
if Algorithm 4: Dominates(b, a ,G)
/* if Dominates returns TRUE */
then a = b
else if not Algorithm 4: Dominates(a ,b, G)
*/ if Dominates returns FALSE */
then C = C ∪ {b}
y = C; O = O ∪ {a}
return O.
Next, in connection with the querying of value information utilizing Algorithm 3, an interrogation policy to instantiate SelectOp in Algorithm 3 is described.
With the observation that a completely augmented order graph, i.e., an order graph where, for any agent, or bidder, i and any bundle b, LB (i, b) =UB (i, b) , precisely decides all dominates relationship (and with the assumption that the information space is finite), any interrogation technique that continuously adds new information to graph G (up to its completion) can be used. However, this does not imply that the graph G must always be completely augmented to determine the solution set.
For example, select a node ∝=(i, b), where i=agent and b=node, from the set of not completely augmented nodes in graph G (that is, LB ∝ ≠GB ∝ ) such that node ∝ is among the nodes in this set with the largest number of relations to allocations in the set of feasible allocation Y. This selection criteria, however, is not to be construed as limiting the invention. Then, ask agent, or bidder, i for the value of bundle b.
Thus, precise valuations are requested directly thereby avoiding the need to use a less direct questions to obtain updated bounds (for example, with questions that ask for incremental (competitive) bidding). Nevertheless, the bidder's response adds new information to graph G in each round until graph G is completely augmented, which is a sufficient requirement for the correctness of Algorithm 12.
Given a set of feasible allocations Y and graph G, the appropriately instantiated Algorithm 3 will determine the set of undominated allocations contained in the set of feasible allocations Y. If the set of feasible allocations Y is initialized to the set of all feasible allocations, the result will be the set of welfare-maximizing allocations.
If the set of welfare-maximizing allocations contains more than one element, all valuations of nodes that are part of those allocations have to be known, i.e., Algorithm 11 will not terminate early. It has been observed that Algorithm 11 cannot be written more intelligently to avoid not terminating early because Algorithm 4 is best for evaluating the available information, and, after the first round, each set of feasible allocations Y only contains allocations that are pairwise incomparable with respect to Algorithm 4. Therefore, upon executing Algorithm 11, it is known that pairwise incomparability is either due to missing information or because the allocations have the same value, but only the latter is a correct reason to terminate. Thus, as long as it is not known whether the allocations in the set of feasible allocation Y have the same value, additional information has to be requested. The querying of this additional information will not be described.
Algorithms that Query Order Information
Next, the querying of order information will be described. Order information allows Pareto-efficient allocations to be determined, but cannot be used to determine welfare-maximizing allocations because that would require quantitative tradeoffs across bidders. The required algorithms to be used in Algorithm 3 to determine welfare-maximizing allocations will now be described.
Given a non-empty set feasible allocations Y and graph G, Algorithm 12 can be used in Algorithm 3 to determine the set of allocations that are not dominated, given the information in hand.
Given a set of allocations U and graph G, the following Algorithm 13 will return FALSE if a pair of allocations exists in U which have been judged incomparable due to lack of information, e.g., if it cannot be determined that a dominates b or vice versa.
(Algorithm 13):
Done o (U, G)
for each {a, b} ∈ U x U a ≠ b do
if not Definitely Incomparable (a, b)
then if ∃i ∈ N : ((i, a i ), (i, b i )), ∉>
and ((i, b i ), (i, a i )) ∉>
then return FALSE
return TRUE.
A pair {a, b} of allocations are Definitely Incomparable, if and only if there is a pair of, {i 1 , i 2 } such that edges (i 1 , a i 1 )>(i 1 , b i 1 ) and (i 2 , b i 2 )>(i 2 , a i 2 ) and no edges (i 1 , b i 1 )>(i 1 , a i 1 ) or (i 2 , a 1 2 )>(i 2 , b i 2 ) exist.
Next, in connection with querying or order information utilizing Algorithm 3, an interrogation policy to instantiate Select Op o in Algorithm 3 is described. The present invention can accommodate any interrogation policy here, but the following two exemplary interrogation policies are disclosed herein for Select Op o (C i , G) in Algorithm 3 for the purpose of illustration. (1) Arbitrarily pick a pair of distinct allocations {a, b} that are incomparable due to a lack of information. Arbitrarily, choose one of the bidders i∈N, for which no order, or rank information, for corresponding bundles a i and b i is available. Ask bidder i which bundle a i or b i is preferred. The answer to this question alone might not be sufficient to order a and b since there may be other unordered bundles in those allocations. Also, this question might not be necessary: it can be possible to deduce the answer from answers to other alternative questions. However, the answer to this question may make asking some other questions unnecessary. (2) Determine the set of pairs of incomparable allocations, U. While doing so, determine a set P of pairs of unordered nodes {(i, a i ), (i, b i )}∈graph G for which ∃a, b∈U, a≠b so that neither ((i, a i ), (i, b i ))∈>nor ((i, b i ), (i, a i ))∈>. Next, select from P a pair p={(i, b 1 ), (i, b 2 )} of nodes so that the number of pairs in U which contain p is maximal. Deciding this edge adds information to the largest number of decisions in the next stage. Then, ask the bidder which bundle is preferred more, b 1 or b 2 .
Given the set of allocations Y, and graph G, for either of the foregoing interrogation policies, executing Algorithm 3 will determine the set of Pareto-efficient allocations contained in Y.
Algorithms that Query Value and Order Information
Next, a method of querying value and order information will be described.
Algorithms 11-13 described above for dealing with value information and for dealing with order information can be integrated to deal with both value and order information together. This is because the Algorithms 11-13 use value and order information to the fullest. The order edges from graph G, and the value information, are used to determine which allocations are still undominated. Also, the order information is used to propagate upper bound UB and lower bound LB information across nodes in graph G.
If Algorithm 11 allows early termination, the set of welfare-maximizing allocations has been found. If Algorithm 13 allows early termination, only the Pareto-optimal allocations have been determined so far.
Any query will suffice as long as it asks a bidder order questions about the bidders unordered bundles (that are included in currently undominated allocations), or value questions about bundles for which the upper and lower bounds differ. Based on the bidders response to the query, the welfare-maximizing allocations can be found. This generally does not even require knowing the value of those allocations since order information can substitute for detailed value information.
Algorithms that Query Rank Information
Allocations that use rank information only cannot determine welfare-maximizing solutions because that requires quantitative tradeoffs across agents, or bidders. However, Pareto-efficient solutions can be determined from rank information as follows.
Given graph G and a set of rank vectors C, the following Algorithm 14 answers TRUE if all elements of the set of rank vectors C are feasible.
(Algorithm 14):
Done r (C, G)
for each c ∈ C do
if ∃i ∈ N : (i, b) ∈ V with R (i,b) = c i
then return FALSE /* Information missing */
if not Feasible(c, G)
then return FALSE else return TRUE.
Rank vector c is feasible if b c , the corresponding set of bundles, is a partition of a subset of Ω. If some of the bundles related to ranks are not known yet, FALSE is returned.
(Algorithm 15):
Candidates r (C, G):
for each c ∈ C do
if Infeasible(c, G)
then C = the solution of Algorithm 16: Expand
(c, C, G).
Infeasibility can often be determined without knowing all rank-bundle relations. If the partial information available is not sufficient to decide infeasibility, Algorithm will return FALSE. Thus, if Algorithms 14 and 15 return FALSE, the information is insufficient.
(Algorithm 16):
Expand (c, C, G) /* Loops over successive rank
vectors */
S = suc (c)
C = C \ {c}
for each s ∈ S do
if not call Algorithm 17: IsDominated (s, C, G)
then C= C ∪ {s}.
(Algorithm 17):
IsDominated(s, C, G): for each c ∈ C do
if c ≦ s
then if not Infeasible (c, G) return TRUE
return FALSE.
Next, in connection with the querying of rank information utilizing Algorithm 3, an interrogation policy to instantiate Select OP r in Algorithm 3 is described. The present invention can accommodate any policy, but two exemplary interrogation policies are disclosed herein for SelectOp r (C, G) in Algorithm 3 for the purpose of illustration: (1) Select from the set of rank vectors C a rank vector c with the least number of ranks without related nodes in G. For each such rank r at position i of c, ask bidder i which bundle is at rank r. (2) Same as (1), but pick only one rank without a related node from c.
Given a set of rank vectors C and graph G, for both interrogation policies, Algorithm 3 can be utilized to determine the set of feasible rank vectors in the (partial) lattice determined by the set of rank vectors C that are either in the set of rank vectors C or dominated only by infeasible rank vectors in the set of rank vectors C. If the set of rank vectors C is initialized to (1, . . . , 1) the resulting set represents the set of Pareto-efficient allocations.
Algorithms that Query Rank and Value Information
Next, the querying of rank and value information and how such information can be used to determine welfare-maximizing solutions will be described.
Initially, the following Algorithms 18 and 19 are instantiated as follows.
(Algorithm 18):
Candidates rv (C, G):
c = arg max d∈C LB(d, G)
if d ∈ C \ {c} with UB(d, G) > LB (c, G)
then C = Expand (c, C, G)
The following Algorithm 19 checks whether the node in the set of rank vectors C with the greatest lower bound might be dominated by an as yet incomparable and potentially feasible rank vector. If so, FALSE is returned.
(Algorithm 19):
Done rv (C, G)
c = arg max d∈C LB(d, G) / * Best valued node * /
if ∃d ∈ C \ {c} with UB(d, G) > LB(c, G) and
not Infeasible(d, G)
then return FALSE else return TRUE
The following interrogation policy is disclosed herein for SelectOp rv (C,G) in Algorithm 3 for the purpose of illustration. Pick the rank vector with the highest lower bound, e.g., c (c has some chance of being among the welfare-maximizing allocations). Pick from the remaining rank vectors a rank vector d with UB d >LB c (d might end up being better than c once enough information is available to decide the dominates relation between c and d).
Next, if there is a rank r in position i in d without a related node (that is, neither the bundle that is ranked by agent, or bidder, i at rank r nor its valuation are known), ask bidder i which bundle is ranked at rank r (this will help to determine the feasibility of the rank vector d). If no such position i with missing bundle information exists, look for a position with no precise valuation information, that is, if there is a rank r in a position i of d and a corresponding node (i, b) with UB(i, b)≠LB(i, b), ask bidder, i the value for bundle b (this helps to improve the accuracy of the bounds on the overall valuation of d). Such a position i will always exist because otherwise the valuation for d would be precisely known already (UB d =LB d ), and, with UB d >LB c , LB d would be greater than LB c , which contradicts the selection of c.
Given a set of rank vectors, C, and graph G, Algorithm 3 can be utilized to determine the set of feasible rank vectors in the (partial) lattice determined by C that are not dominated by other feasible rank vectors in the sublattice. If C is initialized to (1, . . . , 1), the resulting set represents the welfare-maximizing allocations.
Incentive Compatibility (Inducing Truthful Bidding)
The elicitation of bidders preferences regarding their bids, with and without one or more of the foregoing algorithms to guide such elicitation, can be utilized with an incentive compatible auction mechanisms such as the generalized Vickrey auction (GVA). The idea is that the disclosed elicitation method would find a welfare-maximizing solution, but would ask extra questions to be able to find the welfare-maximizing solution under the assumption that each bidder in turn were not participating in the auction. The answers would suffice to compute the Vickrey payments, which would motivate the bidders to bid truthfully. The algorithms discussed above can be used for this purpose by simply ignoring every bidder's bids in turn and asking the ensuing questions for determining the welfare maximizing allocation. If there are lazy bidders that would not participate once their bundles and prices have been determined, the mechanism could interleave the questions pertinent to GVA with questions for determining the overall allocation. This way bidders would not know (at least not directly) which purpose the questions are for. The only open issue to deal with is the concern that the questions that the auctioneer asks a bidder leak information to the bidder about the answers that the other bidders have submitted so far. This makes the auction format not entirely sealed-bid. Since the GVA was originally designed for sealed-bid auctions, it is not totally obvious that it leads to an incentive compatible mechanism when used in conjunction with the above described elicitation method.
To compute each bidder's value in a winning allocation in a manner to encourage bidders to bid truthfully, the winning allocation is determined based on bidder's answers to preference elicitations regarding their bids. Next, the values of the bids forming the winning allocation, absent the value of each bid of one bidder, are summed to obtain a first value. Another winning allocation is then determined absent the one bidder. The values of the bids in the other winning allocation are then summed to obtain a second value. A difference is then determined between the first and second values. This difference is the value assigned to the bid(s) of the one bidder in the winning allocation regardless of the one bidder's bid price(s). In other words, the sum of the one bidder's bid price(s) for each of the one bidder's bid(s) included in the winning allocation is ignored in favor of the difference between the between the first and second values. These steps are then repeated for each bidder having a bid in the first winning allocation. Pricing:
Prices can be helpful if information needs to be elicited to determine and establish an efficient allocation. Prices impose a natural limit on over exaggerating announced valuation, because the transfer of money incurred with paying prices imposes the risk to loose money.
The idea behind pricing is the following. If a bundling is known, the most relevant prices are the prices for the bundles that are part of the efficient allocation. If enforcement should be restricted, prices for super-bundles of the bundles in the allocation have to be linear. For example, assume that B 1 and B 2 are bundles in the efficient allocation and P B1 +P B2 <P B1 P B2 . A buyer wishing to buy super-bundles B 1 B 2 may want to buy B 1 and B 2 separately, possibly destroying the efficiency of the allocation. If the price of super-bundle B 1 B 2 is lower than the sum of the bundle prices, buyers interested in the bundles may form a purchasing cartel to buy the super bundle, again possibly destroying the efficiency. All other prices are rather cosmetic and can be set (non-linear) so that the allocation is self-enforcing, that is each agent would accept a distribution of the bundles according to the computed equilibrium. Given a welfare-maximizing allocation X. A price vector is called coherent with an X, if the prices of all super-bundles in X are linear with respect to the prices for bundles in X and if the sum of prices for each set of sub bundles is equal or higher than the price of the union bundle.
A price vector that solves the following algorithm 20 can be utilized to determine an equilibrium price vector. This price vector p supports the optimal allocation.
Algorithm 20: Minimize ∑ b ∈ B x p b subject to s i + p B ≥ v i ( B ) ∀ i , B ∈ 2 B x ; p B = ∑ b ∈ B p b ∀ B ∈ 2 B x ; ∑ i s i + ∑ b ∈ B x p b = V ; and s i , p b ≥ 0 ∀ i , b .
where X=an efficient allocation of bundles b;
V=the value of the efficient allocation; B x =set of all bundles in X assigned to buyers; and s i =the surplus s of buyer i.
The following Algorithm 21 can be used to establish equilibrium prices. If the existence of equilibrium prices is not guaranteed, Algorithm 21 will require an additional termination check.
Algorithm 21: Pricing p (0, . . . , 0). Compute Y; Compute Δ; Compute J; while J ≠ Ø do i = arg max j∈J Δ j . Pick y arbitrarily from Y i ; p y = p y + Δ i Compute Y; Compute Δ; Compute J;
where p=the price vector containing prices for all goods in Ω′;
N=the set of agents; X=(X 1 , . . . , X n ) is the allocation restricted to buyers; and Y=(Y 1 , . . . , Y n ) is a vector of subsets Ω′.
In Algorithm 21, for each agent i, Y i gives the set of most preferred bundles at the going prices. Additionally, in each round, a set J={j∈N:X i ∉Y i }, and a vector Δ with Δ i =(u i (y i )−p y i )−(u i (X i )−P x i ) for an arbitrarily chosen y i ∈Y i will be computed.
Together with algorithms to determine efficient allocation, the determination of equilibrium price enables two-stage mechanisms to be designed for sealed-bid combinatorial auctions that explore the topological space in which the allocations are embedded and may generate anonymous prices that do not require enforcement.
Conclusion
Combinatorial auctions where bidders can bid on bundles of items can be very desirable market mechanisms when the items sold exhibit complementarity and/or substitutability, so the bidder's valuations for bundles are not additive. However, they require potentially every bundle to be bid on, and there are exponentially many bundles. This is complex for the bidder because of the need to invest effort or computation into determining each valuation. If the bidder evaluates non-winning bundles, evaluation effort is wasted. Bidding on too many bundles can also be undesirable from the perspective of revealing unnecessary private information and from the perspective of causing unnecessary communication overhead. If the bidder omits evaluating (or bidding on) some bundles on which the bidder would have been competitive, economic efficiency and revenue are generally compromised. A bidder could try to evaluate (more accurately) only those bundles on which the bidder would be competitive. However, in general it is difficult to know on which bundle the bidder would be competitive before evaluating the bundles.
The topological structure that is inherent in the foregoing problem can be used to intelligently ask only relevant questions about the bidders' valuations while still finding the optimal (welfare-maximizing and/or Pareto-efficient) solution(s). The rank lattice was disclosed as an analysis tool and a data structure, in the form of augmented order graph G, was disclosed for storing and propagating all of the information that the auctioneer receives. Desirably, the data structure and the storing and propagating of information received by the auctioneer is realized in one or more standalone or networked computers of the type well know in the art. Desirably, the present invention is realized in instructions stored on computer readable medium. When executed, the instructions cause the processor of each of the one or more standalone or networked computers to perform the method of the present invention. However, the present invention can be can also be realized without the use of the one or more standalone or networked computers, albeit less efficiently. Based on received information, the auctioneer can narrow down the set of potentially desirable allocations, and intelligently decide which questions to ask the bidders next.
Three types of elicitation queries were disclosed: value queries (potentially with bounds only), order queries, and rank queries (arbitrarily or in order). Selective interrogation algorithms were disclosed that use different combinations of these to find the desired solution(s). Some of the above-described algorithms focused on the propagation of new information, and would support any interrogation policy. Also disclosed are search-based algorithms that integrate an interrogation policy into the interrogation algorithm in order to use a standard search strategy for interrogation, and in order to not have to use and store the elaborate data structure inherent in policy-independent algorithms.
The invention can also be utilized in connection with ascending, descending or fixed values on items of a bundle. The invention can also be utilized in combination with exchange description data (EDD) of the type disclosed in co-pending U.S. patent application Ser. No.: 10/254,241, filed Sep. 25, 2002, which is expressly incorporated herein by reference, to modify queries of the type disclosed herein and/or to analyze bids in view of the answers to such queries.
Briefly, U.S. patent application Ser. No. 10/254,241 discloses a method of processing an exchange. (A forward auction and a reverse auction are simply special cases of an exchange). The method includes providing a solver/analyzer responsive to at least one bid of an exchange for determining an infeasible allocation, a winning allocation or a feasible allocation for the exchange. Each allocation has an allocation value associated therewith. At least one bid is received at the solver/analyzer with each bid including at least one item and an associated bid price. Exchange description data (EDD) is associated with the at least one bid. EDD includes at least one of the features of reserve price, free disposal, non-price attribute, adjustment, objective, constraint, feasible obtainer, constraint relaxer, conditional pricing and quote request. The associated EDD can be received at the solver/analyzer which processes the at least one bid in accordance with the at least one feature included in the associated EDD.
The non-price attribute feature can include a bid attribute and/or an item attribute. The bid attribute can be credit history, shipping cost, bidder credit worthiness, bidder business location, bidder business size, bidder zip code, bidder reliability, bidder reputation, bidder timeliness, freight terms and conditions, insurance terms and conditions, bidder distance and/or bidder flexibility. The item attribute can be size, color, weight, delivery date, width, heighth, purity, concentration, pH, brand, hue, intensity, saturation, shade, reflectance, origin, destination, volume, earliest pickup time, latest pickup time, earliest drop-off time, latest drop-off time, production facility, packaging and/or flexibility.
The adjustment feature can include an item adjustment or a bid adjustment. The item adjustment includes a value and a condition, wherein the value is utilized to modify the bid price of at least one bid when the condition is satisfied. The item adjustment is based on an item attribute of at least one bid. The item attribute for an item adjustment can be one or more of the item attributes discussed above in connection with the non-price attribute feature.
The condition can be formed utilizing at least one of the following operators associated with a condition: equal to, less than, less than or equal to, greater than, greater than or equal to and contains-item.
The objective feature can establish a maximization goal or a minimization goal for the exchange. The objective feature can also include one of a surplus, a traded ask volume, a traded bid volume, a traded average volume, a number of winning bidders and a number of losing bidders.
The constraint feature can include a cost constraint, a unit constraint a cost requirement, a unit requirement, a counting constraint, a counting requirement, a homogeneity constraint and/or a mixture constraint.
The constraint relaxer feature can cause the solver/analyzer to relax at least one soft constraint placed on an exchange and to determine a value associated with such relaxation. The exchange can also include at least one hard constraint that the solver/analyzer cannot relax.
The conditional pricing feature can include a cost conditional pricing that causes the solver/analyzer to modify a value of an allocation based on a difference between the total awarded currency volume of a first bid group and the total awarded currency volume of a second bid group. Also or alternatively, the conditional pricing feature can include a unit conditional pricing that causes the solver/analyzer to modify a value of an allocation based on a difference between an awarded unit volume of a first bid group and an awarded unit volume of a second bid group.
The reserve price feature can cause the solver analyzer to establish a maximum price above which a bid for an item or bundle of items will not be bought, and/ or establish a minimum price below which a bid for an item or bundle of items will not be sold.
The free disposal feature can cause the solver/analyzer to allocate less than an offered quantity of an item for sale without affecting the bid price or allocate more than an offered quantity of the item for purchase without affecting the bid price.
The quote request feature can cause the solver/analyzer to determine for a bid associated with the quote request a price that would result in the bid being included in an allocation.
The invention has been described with reference to the preferred embodiments. Obvious modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | In determining a winning allocation in a forward auction, reverse auction or an exchange, a plurality of allocations are defined wherein each allocation defines a trade between one or more potential buyers and one or more potential sellers. At least one potential buyer is queried regarding at least one preference of the buyer about at least one allocation or a bundle associated therewith. The buyer's reply or intimation to the query is received and, based on the reply or intimation, each allocation that is either not feasible or not optimal is eliminated from consideration as the winning allocation. This process is repeated until a predetermined criteria is met whereupon one of the remaining allocations is selected as the winning allocation. | 6 |
FIELD
[0001] The invention relates to treating particulate and to connecting slab portions.
[0002] The following description focuses on concrete slabs supported by particulate although various aspects of the disclosed methods and apparatus may suit other applications such as:
treating particulate which does not, and is not intended to, carry a slab; treating particulate supporting semi-rigid structure such as asphalt; and connecting slab portions not supported by particulate.
[0006] “Particulate” as used herein takes in crushed rock, gravel, soil, earth, sand and clay, etc. and other materials (e.g. recycled materials) having similar characteristics.
BACKGROUND
[0007] Concrete slabs (e.g. formed of Portland cement) are employed in a variety of applications such as dwelling foundations. In applications such as roads, airport runways and warehouse floors the slabs may also form the exposed surface to which load is directly applied.
[0008] Typically slabs are formed by:
grading the “native” soil; compacting the native soil and/or adding crushed rock, to form a top layer (referred to as a “sub-base”) which may have a higher shear strength than the native soil; installing formwork about the sub-base to define the perimeter of the slab; filling the formwork with wet concrete; and allowing the concrete to set.
[0014] Alternatively, pre-cast slabs may be laid upon sub-base.
[0015] Larger areas, such as roads and runways, are typically formed of a pavement made up of multiple slabs. The multiple slabs may be poured simultaneously (and separated by suitable temporary or permanent formwork). Alternatively, each slab may be poured after its neighboring slab has set. Either way there is a defined boundary between the slabs.
[0016] In use, load applied to the slab (e.g. by car driving along the roadway including the slab or a person standing on a carpet floor supported by the slab) is in turn applied the underlying soil.
[0017] Concrete is weak and brittle in tension. A load applied to a concrete slab at a point of the slab inadequately supported by the soil may cause the slab to crack. The slab may be inadequately supported (by way of example) due to the load being excessive or the soil having subsided away from the load point.
[0018] Cracking can occur at the peripheral margins of a slab (and particularly at the adjacent margins of adjacent slabs) due to “pumping”. When a slab is formed it typically takes on a slightly dished shaped due to differential rates of setting within the body of concrete. This is sometimes referred to “curling”. The dished shape leads to a lower contact pressure (or in extreme cases a cavity) at the interface between slab and soil about the slab's peripheral margins. In turn this leads to relatively more ground water coming and going from the particulate matter under these peripheral margins. This water movement tends to “pump” soil away and so exacerbate the problem.
[0019] Cracking followed by ongoing loading usually leads to an accelerated rate of deterioration. Even if the crack is not a full thickness crack, the load dispersing characteristics of the slab are compromised. A load applied to either of the slab portions defined by the crack is concentrated on the soil underlying that slab portion rather than being more evenly distributed over the soil underlying the entire original slab. This concentrated loading usually leads to accelerated soil subsidence, etc.
[0020] In the past, cracked and sunken concrete has been repaired by injecting material into the underlying soil and adhesively attaching members to span the crack. The present inventors have recognised that these existing approaches are problematic. Often the soil continues to subside and the members come away from slab portions, leading to a further similar failure. Sometimes too much material is injected, leading to a raised portion in the slab.
[0021] Various aspects of the invention aim to provide improvements in and for treating particulate and connecting slab portions, or at least to provide alternatives for those concerned with treating particulate and connecting slab portions.
[0022] It is not admitted that any of the information in this patent specification is common general knowledge, or that the person skilled in the art could be reasonably expected to ascertain or understand it, regard it as relevant or combine it in any way at the priority date.
SUMMARY
[0023] One aspect of the invention provides a method, of treating particulate, in substance including
[0024] at least partly drying the particulate to reduce resistance to injection; and
[0025] injecting material.
[0026] The at least partly drying may be to reduce ground water pressure by about 40 kPa to about 80 kPa. Preferably the at least partly drying is or includes vacuuming.
[0027] The method may include applying a load to the particulate, wherein the injecting material is injecting material below the load, and removing the load.
[0028] The load is preferably selected based on a planned in use loading of the particulate.
[0029] Another aspect of the invention provides a method, of treating particulate, in substance including
[0030] selecting a load based on a planned in use loading of the particulate;
[0031] applying the load to the particulate;
[0032] injecting material below the load; and
[0033] removing the load.
[0034] The method preferably includes, prior to the injecting, at least partly drying the particulate to reduce resistance to injection.
[0035] The load is preferably selected to exert a pressure of at least 1,000 kg/m 2 averaged over the area of the particulate in need of treatment. By way of example, the load may be further particulate as in a “surcharge”.
[0036] The injected material may be allowed to set and further material injected, preferably below the set material. This may involve creating a hole in the set material and the injecting further material may be injecting through the hole so created.
[0037] The methods of the foregoing aspects preferably include sequentially so injecting at a plurality of locations, and most preferably a first of the sequential injections is in substance at a centre of an or the area of the particulate in need of treatment. The depth of each injection in the sequence could be uniform or vary from hole to hole.
[0038] The methods of the foregoing aspects preferably include monitoring the effect(s) of injection and discontinuing injection in response to the monitoring.
[0039] Another aspect of the invention provides a method, of treating particulate, in substance including
[0040] injecting material;
[0041] reducing a rate at which the material is injected to allow time for the effect(s) of injection to become apparent; and
[0042] monitoring the effect(s) of injection; and
[0043] discontinuing injection in response to the monitoring.
[0044] Reducing the rate of injection may be or include periodically pausing the injection (i.e. periodically reducing the rate to zero).
[0045] The monitoring preferably includes monitoring at two or more spaced locations.
[0046] Another aspect of the invention provides a method, of treating particulate, in substance including
[0047] injecting material;
[0048] monitoring the effect(s) of injection at two or more spaced locations; and
[0049] discontinuing injection in response to the monitoring.
[0050] Preferably the monitoring is or includes monitoring surface displacement.
[0051] The injected material may be an expanding material.
[0052] Preferably the particulate is supporting a structure, in which case preferably the method involves sequentially injecting material below the structure to a plurality of injection points spaced about and in proximity to a periphery of the structure's footprint on the particulate.
[0053] Another aspect of the invention provides a method of treating particulate to raise a structure supported by the particulate, including sequentially injecting material below the structure to a plurality of injection points spaced about and in proximity to a periphery of the structure's footprint on the particulate. Material may also be injected at other points (e.g. at the centre of the structure or its footprint).
[0054] The injecting may be in substance injecting material into particulate below a sub-base. The injecting may be injecting through at least one hole in the structure, and the method may include creating the hole(s). The structure may be in substance a slab.
[0055] Another aspect of the invention provides a method, of interconnecting slab portions, in substance including
[0056] removing material from the slab portions to create an elongate feature extending from one of the slab portions into the other of the slab portions and including at least one side formation in each slab portion; and
[0057] inserting into the elongate feature a connection arrangement to co-operate with the side formations to resist lengthwise shear separation.
[0058] Preferably inserting a connection arrangement includes inserting settable material such that the settable material conforms to the side formations, and allowing or causing the so conforming settable material to set to form keys. By way of example, the settable material may be epoxy or urethane.
[0059] Preferably inserting a connection arrangement includes inserting an elongate member, which elongate member may include a portion more flexible than its other portions to accommodate relative movement of the slab portions. The more flexible portion may be or include a transverse deviation.
[0060] The elongate member preferably includes side formations for resisting lengthwise shear separation. The side formations of the elongate member are preferably female. By way of example, the elongate member may be formed of sheet material.
[0061] Preferably the elongate feature is at least as deep as the elongate member is high to fully receive the elongate member. A preferred form of the elongate member is at least 3 times as long as it is high.
[0062] The removing material preferably is or includes cutting a slot and drilling holes along the slot.
[0063] Preferably the removing material is in substance to a depth in the range of ⅓ to ⅔ of a depth of the slab portions or, if the slab portions mutually differ in depth, a thinner of the slab portions.
[0064] Another aspect of the invention provides a method, of repairing one or more slabs supported by particulate, including treating the particulate in the vicinity of a feature defining two slab portions; and connecting the slab portions. The feature defining two slab portions may be or include one or more cracks, or may be a boundary between two slabs.
[0065] Another aspect of the invention provides a joint tie, for tying adjacent slab portions, shaped for receipt within a slot cut into the slab portions and including a portion more flexible than its other portions to accommodate relative movement of the slab portions.
[0066] Also disclosed is a method for repairing damaged or sunken rigid pavement by lifting the sunken slab or a sunken portion of a slab with adequate pre-loading on sunken portion and restoring tensile strength across the slab to prevent future resettlement by:
loading the sunken portion of the slab with weight during injection to simulate actual in service loading condition to prevent further settlement, injecting a hardenable material through the concrete layer and sub-base in multiple passes, while the upward movement of the slab is continuously monitored at more than one location, affixing of formed joint ties to replace failed load transfer dowels or to restore tensile strength of the rigid pavement across cracks against vertical load.
[0070] The added weight might be vehicular axle weight or weight blocks on wheels. Preferably the injection hole is made by drilling 8 mm to 30 mm diameter holes. The diameter of the hole is to be sufficiently large to allow flowable polymer material to flow under pressure.
[0071] Preferably the hardenable material starts to set within four hours after injection to become rigid with compressive strength of greater than 1 kg/cm 2 . This material can be a foamable polymer or multi-component polyurethane expanding to become rigid foam through a polymerisation process after mixing at the injection hole, or premixed foam concrete or premixed fast setting cement slurry.
[0072] Uplifting movement can be monitored using a Benkelman beam or a straight edge or a displacement dial gauge or laser level or an altometer such as ZipLevel™ made by Technidea Inc. The uplifting movement can be monitored with each pass.
[0073] Preferably at least one relief hole is drilled, or a number of holes are drilled within a distance of 1 m to 3 m from the injection hole so that non-solid components under the slab such as air, water can escape, allowing grouting material to substantially fully occupy the void(s) underneath.
[0074] Optionally a small amount of material is injected at a new location between the injected holes after the slab is raised sufficiently. The amount injected is enough to fill the void(s) that may be left between the lifting injection process, and this injection is stopped when there is any sign of upward movement of the slab. This is to prevent possible tensile cracks due to lack of support or existence of voids below the slab.
[0075] The joint ties may be placed across crack lines. The ties are preferably prefabricated metal plate of 4 mm to 8 mm thick inserted into saw cut slots with width of cut slightly larger than the joint tie thickness. The joint ties preferably have 1 mm deep crossed grooves on both ends of the ties to increase surface contact and shear strength of the bonding material. The saw cut slot may also have not-through drilled holes along the slot in a 45 degree angle to vertical direction to increase surface bonding and to also increase shear strength of the joint tie system.
[0076] Preferably the joint tie is placed beyond the end of crack line to prevent propagation of the crack when rigid pavement is subject to cyclic loading.
[0077] Preferably the bonding material has tensile strength greater than shear strength of the base concrete where the tie is affixed to. This material may be a polymer such as urethane or epoxy.
[0078] Preferably small vibration or hammering action is applied to the joint tie so that air bubbles can escape and full surface contact between bonding material, the joint tie and cut slot can be achieved.
[0079] The joint ties may be placed across an expansion joint. The middle of the joint tie may have a half circle kink along the width to allow for deformation along longitudinal direction to accommodate for expansion/contraction movement of the slabs. A hole saw cut (e.g. of 40 mm diameter) may be made to accommodate the kink on the joint tie (e.g. where the saw cut slot intersects with the expansion joint).
[0080] Preferably the selected hardenable material starts to set within four hours after injection to become rigid with compressive strength of greater than 1 kg/cm 2 . This material can be a foamable polymer or multi-component polyurethane expanding to become rigid foam through a polymerisation process after mixing at the injection hole, or premixed foam concrete or premixed fast setting cement slurry.
BRIEF DESCRIPTION OF DRAWINGS
[0081] The Figures illustrate various examples of the methods and apparatus disclosed herein.
[0082] FIG. 1 is a cross-section view of a cracked, particulate supported, slab at an initial stage of treatment.
[0083] FIGS. 2 and 3 are cross-section views illustrating subsequent treatment steps.
[0084] FIG. 4 a is a cut-away view along a slot for connecting slab portions.
[0085] FIG. 4 b is a perspective view of a joint tie.
[0086] FIG. 4 c is a transverse cross-section view of the slot carrying the tie.
[0087] FIG. 5 is a partially cut-away view illustrating an arrangement of slabs and ties transferring load between various slab portions.
[0088] FIG. 6 is a cross-section view of the juncture of a pair of adjacent, particulate supported, slabs at an initial stage of treatment.
[0089] FIGS. 7 a and 7 b are plan views of injection patterns.
[0090] FIG. 8 is a cross-section view of the slabs of FIG. 6 at a subsequent treatment stage.
[0091] FIG. 9 a is a perspective view of a joint tie.
[0092] FIG. 9 b is a perspective view of an alternative joint tie.
[0093] FIG. 10 is a plan view of joint ties connecting slab portions.
DESCRIPTION OF EMBODIMENTS
[0094] In one example, a slab 1 , 2 which is deformed and sunken is raised by injecting, through a drilled-to-sub-grade hole 9 , material 25 such that the injected material will exert about 0.2 MPa to 3 MPa to the surrounding soil. The injected material may be a slurry cement grout or expanding polymer and is shown in the Figures by hatching upwardly inclined to the right.
[0095] The higher end of the range is suitable for slabs (or foundation pads) for which higher loads are planned, such as the slabs of an airport runway—a 30 m 2 slab in an airport runway may have to withstand impact loads (due to heavy landings) of about 150 tons (i.e. about 1.5 MN). On the other hand, the lower end of the range is suited to slabs for which lower loads are planned, such as the slabs of a sidewalk. A pressure of about 0.5 MPa at nozzle is a recommended minimum for normal rigid pavement such as roadways, taxiways or warehouse floors. By way of example foam/cement mix (light weight concrete) may be pumped in under normal air pressure at 0.5 MPa to 0.8 MPa, being the pressure available from most normal air pump compressors.
[0096] Whilst 5 kg/cm 2 is thought to be ample for lifting most slabs, higher pressures are preferred. Preferably polymer equipment supplying about 10 MPa-20 MPa at pump pressure which (minus losses) gives 1 MPa to 3 MPa nozzle pressure is used.
[0097] Good soil would have shear strength of 0.2 MPa upward, and this injection pressure can improve the soil further.
[0098] Material is preferably injected into the soil rather than into the sub-base. If expanding material/grouting material under pressure applies force to the ground/soil 4 with sub-base in between, the stress caused to soil (or the corresponding degree of consolidation/compaction) would be less, therefore it is less effective in terms of trying to put higher stress to soil 4 (hence bring its “past overburden pressure” to a higher level, changing the values of soil's plastic state and elastic state).
[0099] Injection below the sub-base (as opposed to injecting into the sub-base) uses more material but leads to a better longer lasting result. The soil is more “consolidated”. If injection is made on top of the sub-base, the strength of the sub-base will make lifting easier, but the soil is not improved much, and resettlement may follow.
[0100] About 12 to 15 metres is a practical maximum depth of injection using certain existing equipment. 12 m is a readily available tube length, although a few more metres can be achieved by welding another section to it.
[0101] To insert the injection tube into the ground, a core shaft (or “spear”) with a shoulder at the top end (or “driving end”) and a pointed tip at the other ender is inserted into the tube. The core shaft is for example about 8 mm to 9 mm in diameter to suit a ½″ tube with 1 mm wall thickness is used. The core shaft is dimensioned to protrude out of the tube by about 4″ to 8″.
[0102] A hole is drilled through the concrete, sub-base (which may include crushed rock) to get to the native soil. The tube and spear assembly is inserted, and hammered down using any hammering suitable device. An electric hammer such as demolition hammer or rotary drill hammer with hammering only control, between 1000 w to 1500 w in electricity consumption, is found to be an effective device to drive the tube/spear assembly down.
[0103] When the tube reaches a desired depth (where there are weak soils to be improved/compacted), the spear is removed slowly to avoid soil/clay being vacuumed back into the tube and blocking material from flowing out. The depth of injection may be dictated by the actual physical layer(s) of material which are revealed during either soil investigation or Dynamic Cone Penetrometer (DCP) probing. Ideally the tube is then extracted a short distance, e.g. extracted by a couple of inches, to aid the flow of injecting material.
[0104] A similar approach to depth selection may be applied to any subsequent injections through the same injection hole. Injected material will run under pressure to the points of lowest resistance, filling the voids and fissures below the sunken slab. Air, water and/or water-and-fines mixture may be present below the slab or sub-grade, hence desirably vent/bleed hole(s) are made in the slab (e.g. at 1 m to 3 m away from the injection hole) for non-solids to be expelled to enable the filling material to fully occupy any voids.
[0105] With continued injection of material, the slab will rise when the expansion force on the slab is infinitesimally higher than the combined weight of the slab and any loads carried thereby. As the slab starts to move upward, a composite system of ground, sub-base, and grouting material will have modulus of elasticity changed to a value that is able to take the slab load above without being further depressed.
[0106] The injection can be enhanced by at least partly drying the particulate. Water movement through the soil is very slow. When material is injected without drying, it is resisted by water within the soil which cannot escape fast enough. After the injected material has set, there is a high pressure zone in the subsoil water immediately surrounding the injected material. This subsoil water eventually weeps away and so the soil relaxes and is no longer pressurised as it should be.
[0107] For saturated soil, a vacuum tube set at 40 kPa to 80 kPa is placed within a 2 m radius of the injection point, to assist the flow of water, reducing hydrostatic pressure build up that would negate the effect of grouting pressure.
[0108] To prevent post-injection settlement (i.e. further depression of the composite support system) from recurring during service after the repair, weight 17 is added around the local area being lifted to simulate actual in service conditions. The added weight could be a mobile counterweight or rear axle weight of a loaded truck. For a factory floor, the weight should be machinery and goods normally loaded on the floor. For road pavement, the added weight should be around 8 T or more on a rear axle to simulate real life conditions.
[0109] During injection, the effects of injection are monitored to provide an indication of progress. This may involving monitoring the resistance to injection (e.g. a ratio of the injection rate to the injection pressure, the changing resistance being an effect of injection) or sub soil pressure (e.g. with transducers spaced from the point of injection) but preferably is monitoring surface deflection. Surface deflections may be gauged with a Benkelman beam, optical auto level, laser level, displacement gauge, straight edge, dial gauge, altometer (such as ZipLevel™ made by Technidea Inc) or Falling Weight Deflectometer (FWD). A vane shear test device may be used to ascertain that the shear strength of soft ground has improved to the desired level after injection. A DCP probe may be used to ascertain that soil resistant to dynamic loading of the DCP has improved to the desired level after the injection.
[0110] Since flowable material will flow under pressure to the point of lowest resistance, material may flow away from the injection location, and lifting may occur at some point away from the injection point, and monitoring of upward movement of the slab is desirable at multiple locations to prevent over-lifting. This monitoring can be in the form of string lines, laser device, level meter, displacement gauge or any other apparatus capable of monitoring elevation.
[0111] Lifting the slab with a smaller pressurised area below the slab is more desirable because the pressure needs to be higher for a smaller area to generate the required lifting force to raise the slab and the surcharge above it. Because of this, two component self-expanding polymer is preferred over the other materials due to its quick foam formation which prevents material from flowing too far from the injection point.
[0112] Preferably the hardenable material sets within an hour after injection to become rigid with compressive strength of greater than 1 kg/cm 2 . This material can be a foamable polymer or multi-component polyurethane expanding to become rigid foam through a polymerisation process after mixing at the injection hole, or premixed foam concrete or premixed fast setting cement slurry. Expanding polymers (and other expanding materials) increase in volume after injection.
[0113] A hydrophobic polymer resin (when mixed with, to react with, a suitable hardener) will form rigid foam in a few seconds. The injection material may have a blowing agent to adjust the expansion rate of foam. To confine the flow of expanding polymer, the foaming time of the polymer after injection should be in the range of 10 seconds to 60 seconds, and this can be further adjusted by variation in temperature of the resin and hardener at mixing. Gel time and cream time are temperature dependent—the higher the temperature the shorter the cream time. The mixing is controlled by proportioner equipment.
[0114] During injection, the rate of injection is preferably reduced, and most preferably periodically paused (i.e. reduce to zero), to allow time for the effects of injection to become apparent. The inventors have recognised that various effects of injection (e.g. surface uplift) are not immediately apparent. In the case of expanding injection material, the surface can continue rising after injection has ceased.
[0115] The reduction in injection rate of the material is preferably periodic pausing. This could simply be fixed alternate periods of injection and pausing, or the length of the periods may vary in accordance with a schedule and/or in response to monitored effects of injection. By way of example, the periods of injection may be shortened as injection approaches completion. The discontinuous injection may be controlled by automated means or simply by a user.
[0116] Injection in short bursts has been found to give better control over the expansion force. The bursts should be long enough to have new mixed material expelling old mixed material out of the injection tube. The pause should be short enough (less than the setting time of the material) so mixed material in the injection remains flowable and can be pushed out by newer mixed material in the next injection cycle. The ideal amount injected each time is between 0.5 L to 2 L to confine the expanding polymer within the 0.4 m-to-1.5 m effective radius around the injection hole. In case a smaller effective area is required, an even smaller amount should be injected, then pause to wait for the polymerisation process. A smaller effective area when the weighted portion of the slab is lifted means the system modulus of elasticity is higher, reducing the risk of further settlement.
[0117] During lifting the elevation is monitored and the amount of lift, as a rule of thumb, should not be higher than 2 mm-3 mm. This is to maintain the strain rate on concrete surface to approximately 1/500 to avoid cracking. For a larger and deeper depressed area to be lifted, the polymer injection should be made in multi passes.
[0118] A column of injection material, either fast setting slurry or expanding polymer, can be made to form a pillar from the injecting point to the base of the structure by withdrawing the injection tube while injection material continues to flow.
[0119] With reference to FIGS. 2, 3, 7 a and 7 b, the repair starts at the injection hole with lowest elevation, moving radially outward. FIG. 7 a shows a square array of nine injection holes (i.e. a square pattern). FIG. 7 b shows a central injection hole concentrically surrounded by a circular array of 6 equispaced injection holes. This pattern is referred to as a triangular pattern.
[0120] In FIGS. 7 a and 7 b the injection holes are numbered suggesting the injection sequence. The sequence commences with the central hole, followed by some of the outer holes in an order selected to minimise asymmetrical loading, a return pass to the central hole, followed by the final outer holes.
[0121] A second (and any subsequent) injection operation though the central hole (or any other hole in need of multiple passes) avoids drilling too many holes on the concrete slab. It is preferred that between injection operations, the injector be removed and the hole re-drilled with a slightly smaller or equal diameter to original injected hole. This is to ensure that same size injector will still fit.
[0122] The “re-drilled hole” should be slightly deeper than the last hole, so that the drill bit will not just penetrate through the sub-base, but it will also pierce through the polymer foam already formed between the sub-base and the soil. Newly injected polymer under pressure will also flow through this pierced layer to form new foam layer between the soil, sub-base and concrete slab. This force further enhances the combined system rigidity and therefore becomes lifting force. Material injected during the second pass is shown in FIGS. 2 and 3 with hatching downwardly inclined to the right.
[0123] Once the rigid pavement is lifted to the desired level, another injection in between the injected points should be made to fill the voids which may still exist. This hole also should be drilled through the sub-base layer. Care should be exercised not to over-inject as the voids, if any, should not be as large. At this stage, injection should be stopped if there is any sign of lifting happening.
[0124] Once levelness of the sunken portion is achieved, the holes should be plugged with a suitable plugging material (e.g. a compatible cementitious mix or polymer mix) and it is desirable that any cracks 8 be repaired with crack repair epoxy. Work site preparation is important for the bonding to work properly. In case of severe cracks, the bonding between cracked surfaces may not be enough for load to transfer properly across the broken portions, and the use of joint tie 23 becomes desirable.
[0125] In this example, the joint ties 23 are the flat metal plates with thickness slightly smaller than the width of a circular saw cut 21 . These plates can optionally be electroplated or otherwise surface treated to prevent rusting, or made of stainless steel.
[0126] Preferably the saw has a diamond blade. Wet cuts normally help protect the blade life, prevent dusting, but the cut must be cleaned and dried afterward. Compressed air should be used to clean away the fines in the slot, and also to dry the cut. Not many bonding polymers work well on a wet surface, therefore cleaning and drying the cut slot is highly desirable.
[0127] The joint ties 23 should be made approximately perpendicular to the crack line, spacing generally between 1 to 2 times slab thickness, and this spacing may be varied to be tighter if the joint ties are made with width slightly smaller than half of slab thickness. This is to ensure that load transfer devices can adequately take the full load. To prevent propagation of the crack when the repaired slab is put in service, a joint tie should be placed past the end of the visible crack line, preferably away from the end at a distance between 1 to 2 times the slab thickness.
[0128] Structural reinforcement bars are normally placed at or near the bottom of the slab, therefore the saw cut should only be made to about ½ of slab thickness and should not extend beyond ⅔ of the slab thickness. The metal joint ties 23 should be made with thickness such that each of the metal plate fits loosely in the cut slot 21 , leaving enough gaps that bonding material can run in under gravity. The width of the metal plate should be (i) less than depth of cut by about 5 mm, (ii) at least half of the slab thickness.
[0129] The inventors have recognised that the weakest point in various existing jointing systems is the bonding and that increased surface contact is desirable to improve the bonding. This is achieved by drilling a series of not-through holes typically of 16 mm diameter, although smaller or larger diameter holes also work, along the saw cut. 8 mm diameter is considered a practical minimum. Two to three holes on each side would be sufficient. The drilled holes provide more surface contact to aid bonding. The holes can be in vertical direction or at an angle to the vertical direction, although an angle of 45 degrees to vertical axis is preferable.
[0130] The slot 21 and holes 22 are together an elongate formation. Cutting and drilling are material removal operations. The holes 22 constitute side formations deviating from the width of the cut. During installation the received adhesive fills and conforms to the holes 22 . When set, the so conforming portions of adhesive constitute keys, the holes 22 constitute keyways and there is positive engagement to resistant lengthwise shearing (i.e. shear in a direction parallel to the length of cut 21 ).
[0131] Whilst the use of joint tie 23 , 25 is much preferred, the formation 21 , 22 could simply be filled with settable material.
[0132] On the metal joint tie plate, a series of side formation 23 a, 25 a are provided to improve the engaging of the plate 21 with the adhesive. The side formations are preferably female as in horizontal, angled, holed or crossed configuration cut lines, most preferably 1 mm deep grooves. The side formations may be on both sides of the metal plate. The middle part of the metal joint tie carries greatest bending moment when the load transfer is active, therefore no drilled holes, no milling, no recesses should be made on this portion to preserve the strength of the tie.
[0133] Straight joint ties can be made for jointing cracks or broken pieces within a concrete slab. When the joint tie is made across different slabs (e.g. to replace or augment damaged load transferring dowel bars), horizontal movements should be allowed for to account for expansion or contraction. A relatively flexible portion 25 b (e.g. kink) at the middle of the tie allows for relative displacement of the slabs in both transverse and longitudinal directions. This is a half circular kink or U shape that is preferably preformed in the metal joint tie. After installation, this kink area placed at the expansion joint is filled with flexible joint sealer, preferably with a typical Shore A hardness of 15 to 40.
[0134] Bonding material can be placed in the slot prior to or after placement of the joint tie. If fine aggregates such as clean dry sands are mixed with bonding material, they should be added after the joint tie is in place. Vibration or hammering about the tie encourages air bubbles escapes to improve the surface contact with bonding material on both slab wall and the joint tie. It is highly desirable that both cut slot and the joint ties are clean and dried, free of dust, oil or moisture.
[0135] By way of example, the bonding material can either be epoxy, urethane or polyurea-based polymer that would have bonding strengths greater than shearing strength of concrete.
[0136] Joint ties 23 , 25 are formed from rectangular plate. This is a convenient shape which sits neatly in an elongate slot 21 of constant depth. Other shapes are possible. Other variants of the plate may have a curved based, e.g. three separate ties could be formed by cutting a 14″ disk along a triangular pattern of chord lines. Joint ties so formed would neatly conform to a slot made by a single vertical movement of a (rotating) 14″ saw blade.
[0137] FIG. 6 illustrates two slabs 1 and 2 connected by an expansion joint 7 filled with joint sealer 10 . Slab 1 has crack 8 which may extend fully through the depth of the slab. Pumping may occur and void 5 could present below the slabs, containing air or water or water-mixed-with-fines -soil. Below the slab there could exist a course of sub-base 3 which may be damaged around the depressed area of the slab above. Soil 4 below the sub-base may have further voids or interconnected voids 6 .
[0138] To treat the particulate 3 , 4 to re-level and reinforce slabs 1 , 2 , a hole 9 is drilled. The hole 9 passes through the sub-base 3 to soil layer 4 .
[0139] The hole is preferably about 16 mm for the injection of multi-component expanding polymer. For cement grouting, this hole should be between 24 mm to 32 mm, depending on the slurry and injection equipment. Diameters in the range of about 6 mm to 40 mm are considered practical. The holes 9 should be between 0.5 m to 2 m apart. For expanding polymer injection, the distance should be about 1 m to 1.5 m.
[0140] On top of the slabs 1 , 2 as close as possible to the injection hole 9 , weight 17 is added to simulate real loading condition. For road and taxiway pavements, the weight should be a vehicular axle or equivalent carrying 8 T.
[0141] An injector 11 is hammered into the drilled hole such that its friction is strong enough to resist a pullout force of approximately 300 kg or greater for injection hole of 16 mm diameter. This pullout force is proportional to the hole's diameter. If the slab 1 is topped with layer(s) above it, the injector should be placed to the bottom layer and above the sub-base. This is to prevent delaminating of the topping layers. A typical example of this is semi-rigid asphalt coating over Portland cement concrete in road pavement, which exists in many highways or runways.
[0142] On top of the injector 11 , a coupler or valve 12 is affixed to enable attachment of injection gun 13 which provides total control of the flow of resins which are fed through a set of hoses 14 from the material pump.
[0143] Injection of resin should be made in intervals, with each injection cycle providing between 0.5 L to 2 L, pausing not longer than gel time of mixed resin material.
[0144] For raising a sunken slab, a stringline or Benkelman beam 18 is to be used to monitor the uplift of the slab during injection. The uplift movement should not exceed 3 mm to avoid tension cracks due to lifting. For simple void filling, a laser level or infrared device can be used to detect upward movement.
[0145] Injection is preferably made in order, firstly from the lowest point (point 1 ) and moving outward (points 2 , 3 and 3 , 4 ), with reinjection at the most sunken point at each cycle (point 6 ), until all are raised sufficiently. During the injection, the surcharge weight should be placed as close to the injection point as practicable.
[0146] Each reinjection, the hole must be re-drilled past the layer of injected material 15 so newly injected polymer can again apply expanding pressure between soil and the layer of sub-base or concrete slab above the soil to raise the slab and weight above. Once injected material is set, the injection apparatus can be removed for using on the next hole. A valve 12 may be used to allow the removal of the injection gun before material is set.
[0147] Once the broken piece is raised to the desired level, load transfer ties 23 can be installed across cracks that fail to transfer load (typically cracks which are larger than 1 mm in width). These load transfer ties are zinc plated preformed steel plate of 4 mm thickness, with cut lines 23 a preferably in diamond or X pattern. These cut lines will increase bonding strength, avoiding shearing failure of bonding material along the tie's surface when the load transfer is active. The ties will have vertical width (W) of ½ to ⅔ of slab thickness, and length (L) of greater than three times the vertical width (typically 3 W<L<6 W).
[0148] To insert the tie, saw cut 21 is made with a diamond cutting blade of depth to be 5 mm to 8 mm deeper than the width (W) of the tie. Bonding assist holes 22 must be drilled on the concrete to just beyond the depth of the saw cut. These drilled holes will provide extra surface contact for better bonding to concrete surface. At least one hole is to be made on each side of the crack.
[0149] After cleaning out cut slot 21 and drilled holes 22 with dry air (safety precaution should be observed to protect eyes and ears), epoxy or urethane adhesive 24 can partially be poured or pumped into the slot, then the joint tie 23 placed in position. The joint tie 23 should be at least 3 mm lower than slab surface 1 and bonding epoxy 24 can be poured in until the material totally fills the cut slot 21 . Light tapping or vibration must be applied to joint tie 23 so that any air bubbles trapped inside the bonding epoxy 24 can escape to ensure that cut grooves 23 a and drilled holes 22 are totally filled.
[0150] Crack 25 should also be filled with crack repair epoxy using low pressure pump or syringes as per manufacturer recommendation.
[0151] When a joint tie is made across the expansion joint to restore damaged dowel bars, the ties 25 will have half circle kink 25 b of 20 mm wide in the middle. Grooves 25 a retain the same details as those 23 a used on flat joint ties 23 for strengthening cracks.
[0152] The kink 25 b will be placed to define an expansion joint within a Ø40 mm hole 26 , although a larger hole or slightly smaller hole is also acceptable, is made to accommodate the kink with adequate clearance to allow for horizontal movement. This hole 26 will be filled with flexible sealer such as silicone or bituminous sealer 27 .
[0153] Once the bonding material 24 has adequately set and gained strength (preferably at least higher than concrete), the slab can be put back in service (e.g. the roadway can be opened to traffic).
[0154] Pumping (and/or other factors) can lead to an entire structure sinking. The inventors have discovered that by sequentially injecting material at injection points about the structure (rather than simultaneous injection at multiple points or a single larger injection) leads to soil about each injection point being stressed beyond the necessary average, leading to improved soil compaction.
[0155] As noted, in extreme cases voids may form between, and separate, particulate and overlying structure. For the avoidance of doubt, material injected into such voids will act on the underlying particulate. Accordingly, so injecting fits the description of treating the particulate as these words are used herein. | A method of treating particulate, in substance including selecting a load based on a planned in use loading of the particulate; applying the load to the particulate; injecting material below the load; and removing the load. | 4 |
BACKGROUND
1. Field of the Invention
The present invention relates to video display devices, and more particularly, to amplifiers and cut-off control circuits for adjusting the white balance of display devices.
2. Description of the Related Art
In a display device such as a monitor, a white balance adjustment makes a white object appear white regardless of the color temperature. In particular, in a cathode ray tube (CRT), a white balance adjustment adjusts gains and biases of signals applied to red, green, and blue (RGB) guns or cathodes in the CRT. The bias adjustment is often referred to as a cut-off adjustment. Cut-off control circuits can employ a DC-coupling or an AC-coupling when driving cathodes of a CRT. The coupling mode of the cut-off control circuit does not affect the gain adjustment since the gain controls an AC signal component that both AC and DC couplings transfer. However, the coupling mode does affect the bias adjustment, and cut-off control circuits typically require different integrated circuit chips according to the type coupling employed. A further concern is that brightness control depends on a combined RGB signal, but the cut-off control, which controls cathode biases, is carried out for each of the R, G, and B signals separately. In order to adjust the white balance, the brightness level is adjusted first, and then the cut-off control is performed.
FIG. 1A is a circuit diagram of a conventional cut-off control circuit having a DC-coupling to the video portion of a monitor (e.g., a cathode in a CRT). The cut-off control circuit of FIG. 1A includes a video pre-amplifier 101 and a drive amplifier 102 for driving a CRT. For simplicity, FIG. 1A shows only one channel even though a color video system normally has three channels (R, G, and B). The cut-off control adjusts the respective CRT cathode bias voltages VA for the R, G, and B cathodes. In FIG. 1A, a video feedback voltage Vf provides a negative feedback to pre-amplifier 101 . Pre-amplifier 101 controls an output voltage Voutput so that video feedback voltage Vf is the same as or depends on a brightness control voltage Vbright. A current controller 103 controls video feedback voltage Vf and thus controls voltage Voutput and CRT cathode bias voltage VA. Equation 1 expresses CRT cathode bias voltage VA as a function of feedback voltage Vf, resistances R 1 and R 2 of respective resistors 104 and 105 , and a current Ic. V A = V f * R1 + R2 R2 + Ic * R1 Equation 1 :
As can be seen in Equation 1, the CRT cathode bias voltage VA depends on the control current Ic, which a cut-off control signal Vcutoff can adjust.
FIG. 1B is a circuit diagram of the conventional video pre-amplifier 101 shown in FIG. 1A, in which an external feedback brightness control method is used. Referring to FIG. 1B, the video pre-amplifier 101 includes an adder 110 a , a drive amplifier 101 b , a comparator 101 d , and a switch 101 c.
FIG. 2A is a circuit diagram of a conventional cut-off control circuit using an AC-coupling mode. The cut-off control circuit of FIG. 2A includes a video pre-amplifier 201 , a drive amplifier 202 , a coupling capacitor 203 , and a comparator 204 . This circuit uses a separate DC bias circuit that controls cathode bias voltage VA. Only an AC component of the output signal from drive amplifier 202 passes through a coupling capacitor 203 to voltage VA. Equation 2 expresses cathode bias voltage VA as a function of a reference voltage Vref, resistances R 3 , R 4 , and R 5 of respective resistors 213 , 214 , and 215 , and cutoff voltage Vcutoff. V A = Vref * R3 + R4 + R5 R3 * R5 - Vcutoff * R4 R5 Equation 2 :
As shown in the equation 2, cathode bias voltage VA depends on cut-off control voltage Vcutoff which is applied to a comparator 204 to adjusts a control current Ic.
FIG. 2B is a circuit diagram of video preamplifier 201 shown in FIG. 2A, in which a built-in feedback brightness controlling method is used. The video pre-amplifier 201 of FIG. 2B includes an adder 201 a , a drive amplifier 201 b , a comparator 201 d , and a switch 201 c.
As mentioned above, the video pre-amplifiers 101 and 201 of the conventional cut-off control circuits respectively using DC-coupling and AC-coupling differ from each other. Thus, conventional cut-off control circuits using different coupling modes require different integrated circuits and external parts. Further, the cut-off control circuits require a number of external parts, such as an operational amplifier and resistors, in addition to the video pre-amplifier. This makes the circuits more complex.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a video pre-amplifier that can be implemented on a single IC chip and can be used in cut-off control circuits using both AC-coupling mode and DC-coupling mode. Another object of the invention is to provide a cut-off control circuit that requires fewer external components other than a video pre-amplifier IC chip.
To achieve the above objects, a preamplifier according to an embodiment of the invention includes a switching unit for receiving control data, generating a bus control signal according to the control data, and outputting the bus control signal internally or externally. The switching unit provides a bus control signal internally, when the preamplifier operates in a cut-off control circuit that uses DC-coupling. The switching unit provides a bus control signal to an external bias circuit when the preamplifier operates in a cut-off control circuit that uses AC-coupling.
BRIEF DESCRIPTION OF THE DRAWINGS
The above object and advantages of the present invention will become more apparent by describing in detail a preferred embodiment thereof with reference to the attached drawings in which:
FIG. 1A illustrates a conventional cut-off control circuit using a DC-coupling;
FIG. 1B is a circuit diagram of a video pre-amplifier shown in FIG. 1A;
FIG. 2A illustrates a conventional cut-off control circuit using a AC-coupling;
FIG. 2B is a circuit diagram of a video pre-amplifier shown in FIG. 2A;
FIG. 3 illustrates a cut-off control circuit with a DC-coupling and a video amplifier of a preferred embodiment according to the present invention;
FIG. 4 illustrates a cut-off control circuit with an AC-coupling and the video amplifier from FIG. 3;
FIG. 5 is a circuit diagram of another embodiment of the video pre-amplifier according to the present invention;
FIG. 6 is a circuit diagram of yet another embodiment of the video pre-amplifier according to the present invention; and
FIGS. 7A through 7C are graphs showing simulated performance of a cut-off control circuit according to the present invention.
Use of the same reference symbols in different figures indicates similar or identical items.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 shows a cut-off control circuit in accordance with an embodiment of the invention. The cut-off control circuit includes a video pre-amplifier 300 and a drive amplifier 350 that uses a DC-coupling to a cathode of a cathode ray tube (CRT), not shown. In accordance with an aspect of the invention, video pre-amplifier 300 can be formed on an integrated circuit (IC) chip and employed in a cut-off circuit using either a DC coupling (as shown in FIG. 3) or an AC coupling (as shown in FIG. 4 and described below). In FIG. 3, video pre-amplifier 300 amplifies a sum of a video input signal Vinput and a bias control voltage Vbc and applies an amplified output signal Vo to drive amplifier 350 . Drive amplifier 350 amplifies signal Vo and drives the CRT in the video system. Video pre-amplifier 300 includes a first adder 301 , an amplifier 302 , a second adder 303 , a switching unit 304 , an analog comparator 305 , and a clamping switch (or transistor) 306 . Switching unit 304 includes a bus control block 304 a , a digital-to-analog (D/A) converter 304 b , a switch 304 c , and an I/V converter 304 d.
Adders 301 and 303 add analog voltages. In operation, adder 301 adds video input signal Vinput to bias control signal Vbc and applies the resultant sum to amplifier 302 . Amplifier 302 amplifies signal output from adder 301 , and outputs the amplified signal as video output signal Vo from video-preamplifier 300 . Adder 303 adds an output signal Vda from switching unit 304 to a brightness control signal Vbright and applies the resultant signal Vc to an input terminal of comparator 305 . A microcontroller (not shown) or an on-screen display (OSD) controller (not shown) in the video system generates brightness control signal Vbright to indicate a desired brightness of the CRT image. Comparator 305 compares signal Vc from second adder 303 with video output signal Vo from amplifier 302 and generates an output signal having a level that depends on the difference between signal Vc and video output signal Vo. Clamping switch 306 closes or opens in response to pulses in a signal CGPulse from the microcontroller and connects or disconnects the output signal from comparator 305 to adder 301 and a capacitor C 1 . The signal CGPulse is activated during a back porch period of the video input signal. Capacitor C 1 is typically external to a pre-amplifier integrate circuit 300 . When switch 306 is closed, comparator 305 charges (or discharges) capacitor C 1 by drawing or supplying a current to capacitor C 1 depending on the compared result. The voltage difference across capacitor C 1 is provided as the bias control signal Vbc to the adder 301 . Due to the operation of the feedback loop, signal Vbc reaches such a voltage that signals Vo and Vc have equal magnitude. When switch 306 is open, capacitor C 1 clamps or holds signal Vbc at a nearly constant voltage. In particular, capacitor C 1 limits an AC component of bias control voltage Vbc which may result from the AC component of signal Vo.
In switching unit 304 , bus control block 304 a receives serial control data from the microcontroller via an inter-IC bus (IIC bus) and stores such data in an internal register for output as a parallel signal. (For example, 8-bit parallel data signals indicating a cut-off level for an R, G, or B cathode in the CRT.) A digital-to-analog (D/A) converter 304 b receives the bus control data from bus control block 304 a and converts the bus control data into an analog control current signal. Switch 304 c transfers the control current signal from D/A converter 304 b either to current-to-voltage (I/V) converter 304 d or to the terminal for cut-off signal Icutoff depending on a selection control signal from bus control block 304 a . Here, the control current signal is negative, i.e., D/A converter 304 b draws current from either I/V converter 304 d or the Icutoff terminal. When I/V converter 304 d receives the control current signal, converter 304 d converts the current signal into control voltage signal Vda. The microcontroller can provide the selection control signal with a value that indicates the type of coupling used in the cut-off control circuit. In FIG. 3, the cut-off control circuit uses a DC coupling to the CRT, and switching unit 304 operates in a mode referred to herein as DC-coupling mode or internal mode where switch 304 c provides a path from D/A converter 304 b to IN converter 304 d.
For control of the bias voltage using a DC coupling, comparator 305 (or charged capacitor C 1 ), adder 301 , and amplifier 302 form a negative feedback loop which sets the steady state or DC level of voltage Vo equal to control voltage Vc. Equation 3 shows the relationship of the DC component of video output voltage Vo to signals Vc, Vbright, and Vda.
Vo=Vc=V bright+ Vda. Equation 3:
Signals Vbright, Vda, and Vc respectively denote a brightness control voltage, the output voltage of switching unit 304 , and the output voltage of second adder 303 . Sequential conversion of data from bus control block 304 a can change voltage Vda to perform the cut-off control for each of the RGB cathodes and therefore change output voltage Vo to appropriate values for each of the RGB cathodes.
FIG. 4 shows a cut-off control circuit employing pre-amplifier 300 and a drive amplifier 450 with an AC-coupling to the video system. The configuration of video pre-amplifier 300 in FIG. 4 differs from the corresponding configuration in FIG. 3 in that switching unit 304 operates in an AC-coupling mode. In particular, switch 304 c routes the control current signal from D/A converter 304 b to an output terminal for cut-off signal Icutoff. To implement the AC coupling, the cut-off circuit of FIG. 4 includes a capacitor 462 coupled between drive amplifier 450 and an output node 465 . Amplifier 450 provides an AC video signal to node 465 . A DC bias circuit for node 465 includes resistors R 1 and R 2 and a transistor Q 1 . Resistor R 1 is between node 465 and a supply voltage Vb. Transistor Q 1 has a collector connected to node 465 , a base connected to a bias voltage Vbb, and an emitter connected via resistor R 2 to switching unit 304 .
When switch 304 c routes the control current signal to the output terminal for signal Icutoff, the DC voltage to the second terminal of adder 303 is zero. The feedback loop including comparator 305 or capacitor C 1 , adder 301 , and amplifier 302 still drives output voltage Vo to the level of control voltage Vc. Accordingly, Equations 4 express the steady state or DC component of video output voltage Vo and CRT cathode bias VA.
Vo=V bright
VA=Vb−R 1 *Ic Equations 4:
In Equations 4, Vbright, Ic, and Vb respectively denote a brightness control voltage, the magnitude of the output current from D/A converter 304 b , and a supply voltage. As can be seen from Equations 4, D/A converter 304 b by controlling voltage Vda controls the DC component of CRT bias voltage VA.
FIG. 5 illustrates a video pre-amplifier 500 in accordance with another embodiment of the invention. Video pre-amplifier 500 includes a first adder 501 , an amplifier 502 , a second adder 503 , a switching unit 504 , a comparator 505 , and a clamping switch 506 which are respectively similar or identical to first adder 301 , amplifier 302 , second adder 303 , a switching unit 304 , comparator 305 , and clamping switch 306 of FIG. 3. A primary difference between pre-amplifier 300 of FIG. 3 and pre-amplifier 500 of FIG. 5 is that second adder 503 has a positive input terminal coupled to the output terminal of amplifier 502 and a negative input terminal coupled to the output terminal of switching unit 504 . An output voltage Vf′ from adder 503 is thus equal to output voltage Vo minus the voltage from switching unit 504 .
Cut-off control circuits using DC-coupling and AC-coupling, similar to those of FIGS. 3 and 4 can use pre-amplifier 500 in place of pre-amplifier 300 . In a DC coupling mode of pre-amplifier 500 , a negative feedback loop including comparator 505 (or charged capacitor C 1 ), adder 501 , amplifier 502 , and adder 503 drives voltage Vf′ to an equilibrium level equal to brightness control voltage Vbright. Accordingly, in DC coupling mode, Equation 5 gives output voltage Vo in terms of voltages Vbright and Vda.
Vo−Vda=V bright or Vo=V bright+ Vda Equation 5:
In AC coupling mode, switching circuit 504 grounds the negative input to adder 503 , and output voltage Vo is the same as for pre-amplifier 300 in FIG. 4 .
FIG. 6 illustrates a video preamplifier 600 in accordance with yet another embodiment of the invention. Pre-amplifier 600 of FIG. 6 can replace pre-amplifier 300 in cut-off control circuits using DC-coupling and AC-coupling, similar to those of FIGS. 3 and 4.
In FIG. 6, video pre-amplifier 600 includes a video input clamping unit 601 , an amplifier 602 , a first adder 603 , a switching unit 604 , and a second adder 605 . Switching unit 604 includes a bus control block 604 a , a digital-to-analog (D/A) converter 604 b , a switch 604 c , and an I/V converter 604 d . Video input clamping unit 601 , which is optional, receives a video input signal Vinput and an OSD signal from an OSD controller (not shown) and matches the black level of video input signal Vinput to that of the OSD signal. Video input clamping unit 601 applies a level-adjust video input signal to amplifier 602 for amplification.
In switching unit 604 , D/A converter 604 b receives digital bus control data from bus control block 604 a and converts that data into an analog control current signal. Switch 604 c directs the analog control current signal from D/A converter 604 b either to I/V converter 604 d or to the output terminal for cut-off signal Icutoff according to a selection control signal from bus control block 604 a . When I/V converter 604 d receives the control current signal, converter 604 d converts the current signal into control voltage signal Vda. Second adder 605 adds the output signal VDA from switching unit 604 to brightness control signal Vbright. First adder 603 adds the output signal from amplifier 602 to the output signal of second adder 605 and outputs the sum as video output signal Vo. Accordingly, in DC coupling mode, adder 603 shifts the DC component of output from amplifier 602 by the sum of signals Vbright and Vda.
FIGS. 7A through 7C show plots of the results of a simulation of the circuit of FIG. 4 . In the simulation, the bus control data from bus control block 404 a sweeps from 00h to FFh and then to 00h again. FIGS. 7A and 7B respectively show the waveforms of a collector current It and an emitter current Ic of transistor Q 1 . FIG. 7C shows the waveform of the DC component of output voltage VA, which is output to a CRT cathode. As can be seen in FIG. 7C, the DC bias of the output voltage VA varies across a range according to the bus control data. Therefore, the bus control data can set the DC bias of output voltage VA as required within the range. Further, a specific value of the bus control data can be easily selected and set during manufacture.
As described above, the pre-amplifier includes a built-in bus control block and D/A converter that is usable in the cut-off control circuits using both DC-coupling and AC-coupling. The chip size of the pre-amplifier is not greatly increased for this added flexibility since separate sets of control blocks and D/A converters, one for DC-coupling mode and one for AC-coupling, are not required. Instead, a switch selects the operating mode and use of the control block and D/A converter. Furthermore, in either a control circuit employing DC or AC coupling, the number of required components in addition to the video pre-amplifier IC chip is low, which lowers manufacturing cost of the cut-off control circuits.
In alternative embodiments of the present invention where only DC-coupling or only AC coupling is required, switch 304 c , 504 c , or 604 c may be omitted from in the respective pre-amplifier 300 , 500 , or 600 . In such embodiments, the output signal of the D/A converter 304 b , 504 b , or 604 b is provided directly to either the I/V converter or the Icutoff terminal depending on the coupling mode for the pre-amplifier 300 , 500 , or 600 . When the pre-amplifier is employed in a DC coupled cut-off control circuit, adder 303 , 503 , or 605 , which is used adding the output signal of the switching unit to the video output signal Vo or the brightness control signal Vbright, may be omitted.
Having described and illustrated principles of the invention in specific embodiments, it should be apparent that the invention can be modified in arrangement and detail without departing from such principles. We claim all modifications and variation coming within the spirit and scope of the following claims. | Cut-off control circuits implementing DC-coupling and AC-coupling to CRT cathodes can employ the same preamplifier integrated circuits with few additional components. The preamplifier includes a switching unit for receiving control data, generating a control signal according to control data, and outputting the control signal internally or externally. The switching unit provides a control signal internally to an amplification circuit, when the preamplifier operates in a cut-off control circuit having a DC-coupling to a CRT. With a DC coupling the amplification circuit controls a DC bias applied to a CRT cathode. The switching unit provides a bus control signal externally to a bias circuit, when the preamplifier operates in a cut-off control circuit having an AC-coupling to a CRT. | 7 |
This application is a continuation of application Ser. No. 403,252 filed Mar. 10, 1995, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention pertains to apparatus for dispensing flowable materials, and more particularly to such apparatus which is suitable for automated operations.
2. Description of the Related Art
With increasing emphasis on inventory reduction and innovative manufacturing management techniques, such as "just in time," and other techniques, custom blending of recipes is becoming increasingly important in a variety of different industries. For example, food flavorings, cosmetics, paints and inks are being custom blended to produce formulations in made-to-order quantities on demand.
There is an increasing emphasis today on compact automated dispensing apparatus. Problems are encountered, however, when attempts are made to compact high throughput automated dispensing equipment used in a high volume production environment. Consideration must be given not only to the larger size of the dispense valves required, but also to the routing of conduits which are significantly increased in cross-sectional size so as to accommodate the higher throughput rates of the system. These and other related factors make it difficult to provide dispense assemblies having the capability of dispensing a plurality of formulation ingredients. For example, paint coatings require a plurality of different color tinting materials. Tinting systems having as many as 8 to 16 different colors are commonly employed in the paint industry. Dispense equipment for such applications meters the requisite amount of different tint materials, depositing them into a common container, which usually contains a base paint mixture. Thus, a plurality of different dispense valves, even though of large throughput capacity, must be closely positioned so as to accommodate a standard size container.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide dispensing apparatus for formulating recipes using a plurality of different ingredients.
Another object according to the principles of the present invention is to provide a dispense head of the above-described type which allows relatively high throughput rates, but which is compact in size so as to be able to accommodate standard size containers.
Another object according to the principles of the present invention is to provide dispense apparatus of the above-described type which is flexible in operation so as to accommodate different conveyor configurations transporting materials to and from the dispenser apparatus.
Yet another object of the present invention is to provide dispensing apparatus of the above-described type which can readily accommodate different types of dispense valves.
A further object according to the principles of the present invention is to provide dispense apparatus of the above-described type which can be assembled from a minimum number of inexpensive parts, with minimal labor investment.
These and other objects according to the principles of the present invention are provided in dispensing apparatus, comprising:
a plurality of valves arranged along first and second nested curved lines, the valves having housings with upper ends and coupling means at the upper ends for releasably engaging an actuator arm, the coupling means operating the valves between open and closed positions when moved with respect to the valve housing;
an actuator arm releasably engageable with the valve's coupling means; and
mounting means for mounting the actuator arm for movement across the valves, passing the arm into and out of engagement with the valves it crosses, and said mounting means mounting the actuator arm for movement toward and away from the valves to open and close the valves so as to dispense material from the valves.
Other objects are provided in dispensing system for dispensing a plurality of different materials, comprising:
a dispense cabinet;
a plurality of storage tanks containing at least some of the materials to be dispensed;
a plurality of valves arranged within the cabinet along first and second nested curved lines, the valves having housings with upper ends and coupling means at the upper ends for releasably engaging an actuator arm, the coupling means operating the valves between open and closed positions when moved with respect to the valve housing;
conduit means coupling the tanks to the valves;
plurality of pumps for pumping the materials to the valves;
the cabinet including container supporting means for supporting a container underneath the valves, to receive material dispensed from the valves;
an actuator arm releasably engageable with the valve's coupling means; and
mounting means for mounting the actuator arm for movement across the valves, passing the arm into and out of engagement with the valves it crosses, and said mounting means mounting the actuator arm for movement toward and away from the valves to open and close the valves so as to dispense material from the valves.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of dispense apparatus according to principles of the present invention;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a side elevational view thereof;
FIG. 4 is a view shown partly in cross section, taken along the line 4--4 of FIG. 2;
FIG. 5 is a view shown partly in cross section, taken along the line 5--5 of FIG. 4;
FIG. 6 is a view similar to that of FIG. 5, but showing the actuator arm in a raised position;
FIG. 7 is a cross-sectional view taken along the line 7--7 of FIG. 4;
FIG. 8 is a cross-sectional view taken along the line 8--8 of FIG. 6;
FIG. 9 is a fragmentary cross-sectional view showing a portion of FIG. 8 on an enlarged scale;
FIG. 10 is a cross-sectional view showing an alternative embodiment of a dispenser according to principles of the present invention;
FIG. 11 is a fragmentary view taken along the line 11--11 of FIG. 10;
FIG. 12 is a cross-sectional view of another alternative embodiment of dispenser apparatus according to principles of the present invention;
FIG. 13 is a top plan view of an alternative dispenser system according to principles of the present invention;
FIG. 14 is a front elevational view thereof;
FIG. 15 is a top plan view of another alternative embodiment of a dispenser system according to principles of the present invention; and
FIG. 16 is a front elevational view thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, and initially to FIG. 1, a dispenser system according to principles of the present invention is generally indicated at 10. A conveyor 12 transports containers 14 through a dispense station 16. A plurality of tanks 18 feed material to be dispensed to station 16. FIG. 3 shows a series of pumps 22 delivering material from tanks 18 to dispense station 16. As shown in FIG. 2, dispense valving apparatus generally initiated at 30 includes a plurality of inlet conduits 56 and outlet conduits 58, coupled to tanks 18. The dispense apparatus 30 deposits quantities of material from tanks 18 into a container 14 placed below the dispense apparatus. Dispense station 16 includes a weigh scale 38 which supports a movable section of conveyor, designated by numeral 40. Scale 38 is coupled to an electronic control device 100 (see FIG. 4) through conductors 44. Signals from scale 38 are used to control the dispensing of material into container 14, to assure metering accuracy.
Turning now to FIG. 4, dispense apparatus 30 includes a plurality of valves 50 disposed within a mounting block 52. In the preferred embodiment, sixteen valves 50 are provided, and are arranged in mounting block 52 in multiple nested curved lines, preferably in the form of two concentric circles. The valves 50 are coupled to inlet and outlet conduits 56, 58, which are also mounted in block 52. Valves 50 have a bottom end 62 with a center valve 64 and an outer annular valve 66 concentrically arranged with respect to valve 64. The valves 64, 66 are open and closed by reciprocation of valve shaft 70 which has an enlarged end 72. Referring additionally to FIG. 5, a gripper arm 80 is mounted on drive shaft 82 for rotation about a vertical axis. As can be seen in FIG. 5, the gripper arm 80 includes keyhole-shaped sockets 86, 88, which are downwardly facing, and which have openings 90, 92 at their lower ends.
An actuator 96 is operated by vacuum under the control of a programmable logic controller or the like conventional control device 100. Actuator 96, which can be electrical or hydraulic as well as pneumatic, has a shaft 102 with a coupler 104 which engages the enlarged upper end of drive shaft 82. As actuator 96 reciprocates its output shaft in a vertical direction, drive shaft 82 is reciprocated a like amount, thereby raising and lowering the gripper arm 80. Actuator 96 is preferably of the stepless type, thus allowing flexibility in accommodating valves of different types. Drive shaft 82 is mounted for reciprocation on support shaft 112. A motor 114, operated under control of device 100, drives a bevel gear 116 which engages a splined portion 118 of drive shaft 82 so as to rotate gripper arm 80 about the vertical axis of shaft 82. Referring to FIG. 4, a timing disk 122 is mounted for rotation with drive shaft 82. Angular displacement of timing disk 122 is sensed by photoelectric sensors 126, 128, which are coupled to control device 100 to indicate the angular position of gripper arm 80.
Referring to FIG. 5, a support table 140 is supported from mounting block 52, and in turn supports the legs 144 of actuator 96 to allow actuator 96 to develop thrust in drive shaft 82 in reciprocal vertical directions. Motor 114 and photoelectric sensors 126, 128 are also supported from table 140. The actuator mechanism 130 is mounted on a support table 150 and is surrounded by an upper cabinet member 152, and supported from the floor by a lower cabinet member 154, as shown in FIG. 2.
Referring to FIG. 8, the valves 50 are preferably arranged in two concentric circles, with eight valves in each circle. The drive shaft 82 is positioned at the center of the circles, with gripper arm 80 being mounted for rotation about the center of the circles. With reference to FIGS. 5 and 8, gripper arm 80 is rotated in a horizontal plane as indicated in FIG. 5, with the valve ends 72 passing through the channels 86, 88 and with the actuator shafts of the valves passing through openings 90, 92. The valves in the outer circle pass through channel 86, whereas the valves of the inner circle pass through channel 88. As can be seen in FIG. 8, the valves of the inner circle are staggered (i.e., radially displaced) with respect to the valves of the outer circle. The valves 50, as can be seen in FIG. 8, are thereby arranged in a compact arrangement such that the distance between diametrically opposed valves of the outer circle is held to a minimum length needed to accommodate the inner circle valves as well as the actuating mechanism.
As can be seen in FIG. 8, as gripper arm 80 travels in a direction of rotation, valves of the inner and outer circles alternately pass through the sockets of in the gripper arm. For example, in FIG. 8, the gripper arm 80 is positioned between valves of the inner circle so as to engage a valve of the outer circle. With reference to FIGS. 5 and 6, the gripper arm 80 is then raised by instructions to actuator 96, sent under control of device 100. As shown in FIGS. 5 and 6, the enlarged ends 72 of the valve shafts are held captive in the gripper arm sockets, and accordingly, as the gripper arm is raised, the valve shaft is also raised so as to operate the valve.
FIG. 5 shows the valve in a closed position, preparatory to a dispensing operation, with material being circulated through the valve. Circulation may be continuous, or may be instituted immediately prior to a dispensing cycle. FIG. 6 shows the valve shaft being raised, to move the valve elements to their open positions, and to block recirculation flow through the valve, diverting material through the dispense end 62 of the valve. As mentioned above, valves 50 include two valve elements, a smaller central valve element or needle valve 64 and a larger outer concentric valve 66. By controlling the amount that the gripper arm 80 is raised, the valve elements can be operated in different stages. Upon completing a dispensing operation, the gripper arm is lowered generally to the position shown in FIG. 5, being readied for rotation so as to engage the next valve called for in a formula.
Turning now to FIGS. 10 and 11, an alternative arrangement of the dispensing apparatus is generally indicated at 200. The gripper arm 80 is suspended by a shaft 204 from coupling 104 of vacuum actuator 96. As in the preceding embodiment, actuator 96, through intervening members, raises and lowers gripper arm 80. However, in embodiment 200, the vacuum actuator 96 is carried on a support table 208 which is rotatably mounted on post 210. A drive gear 212 mates with a drive ring 214 located on the bottom surface 216 of table 208. Gear 212 is connected through a shaft 220 to a drive motor (not shown in the FIGURES) supported from support base 152. Gear 212 drives table 208 in a desired direction of rotation, causing the gripper arm to pass over valves 50, as described above. When a desired valve is selected by the control device, gripper arm 80 is positioned over the valve, as described above, and actuator 96 raises the gripper arm so as to operate the selected valve.
Turning now to FIG. 12, an alternative dispensing arrangement is generally indicated at 250. In this embodiment, the shaft 204 is terminated at its bottom end with a shoe 254 received in the slot 256 formed in the upper end of a cylindrical track member 258. The gripper arm 80 is cantilevered from the lower end of shaft 204, at a point adjacent the track member. A support table 208 is rotatably driven by gear 212, as described above.
As described above in FIGS. 1-3, a conveyor 12 passes through housing 16, and an array of storage tanks 18. However, other conveyor arrangements are also possible. For example, turning to FIGS. 13 and 14, conveyor 12 passes across the front of dispense station 16. Shuttle tracks 270 guide a section 272 of conveyor 12 through an opening 276 formed in the lower cabinet member 154. A container 14 travels along conveyor 12, and is stopped on conveyor portion 272. The container is then shuttled underneath the dispense valves 50 in preparation for a dispensing operation. When dispensing is completed, the container 14 is then shuttled back to the position shown in FIG. 13, and travel is continued down conveyor 12. As shown in FIG. 14, conveyor 12 is mounted in a midportion of lower cabinet 154, being spaced above the floor.
Turning now to FIGS. 15 and 16, conveyor 12 is located on the floor, so as to accommodate larger sized containers extending almost the full height of lower cabinet 154.
The dispense apparatus could also be readily adapted for valves arranged in three or more nested curved lines or line segments. For example, the dispense apparatus could have either three nested arcs or three concentric circles, with valves in each circle. The gripper arm for such arrangement would resemble the gripper arm 80, but would be longer if necessary and would have a third socket, aligned with the third circle.
If desired, the valves need not have coplanar enlarged ends. For example, the enlarged ends aligned along different concentric circles could be increasingly elevated in the outer circles. The enlarged ends would therefore lie along the surface of an imaginary, upwardly diverging, cone, with the gripper arm being upwardly inclined to match the angle of the imaginary cone, having downwardly opening sockets as shown in the FIGURES, above.
Further variations are also possible. For example, the valves need not be vertically operable, but could have actuators which move in inclined or even horizontal planes. The gripper arm and related drive assembly could be readily rotated from the horizontal reference plane shown and described above.
As can be seen from above, the dispense apparatus according to the present invention is flexible, being readily adapted to assume a number of different operating configurations, examples of which are discussed above.
Although one type of valve has been described above, it will be readily appreciated that the dispensing apparatus of the present invention can readily accommodate a wide variety of valves commercially available today. For example, valves having a single valve element can be employed.
The drawings and the foregoing descriptions are not intended to represent the only forms of the invention in regard to the details of its construction and manner of operation. Changes in form and in the proportion of parts, as well as the substitution of equivalents, are contemplated as circumstances may suggest or render expedient; and although specific terms have been employed, they are intended in a generic and descriptive sense only and not for the purposes of limitation, the scope of the invention being delineated by the following claims. | A dispenser for flowable materials includes a plurality of dispense valves arranged in two concentric circles. An actuator arm mounted for rotation about the center of the circles glides over the tops of the valves. A pair of channel-like passageways are formed in the arm, one for the valves arranged in the outer circle, the other for the valves arranged in the inner circle. The valves of the inner and outer circles are radially offset from one another, and accordingly a valve from only one of the two circles is engaged at any given time. The arm is mounted for lifting and lowering movements to accomplish a dispense operation. | 8 |
This is a continuation of co-pending application Ser. No. 663,316 filed on Oct. 22, 1984, now abandoned.
BACKGROUND OF THE INVENTION
This invention is in the field of providing a lateral support to the drive nut of a Scotch Yoke mechanism. A Scotch Yoke mechanism is a means for converting the linear motion of a drive nut into rotational motion.
This relates to a means of providing lateral support to the drive nut of Scotch Yoke mechanism and especially to the "operator" as shown in T K Valve & Manufacturing, Inc., brochure 1982, whose address is P. 0. Drawer 2948, Hammond, La. 70404. That operator or assembly has two vertically spaced apart U-shaped arms mounted on a hub. An externally driven screw extends between the upper arms and the lower arms to move a drive nut which is provided between the two arms. The drive nut has an upper and lower extending cylindrical member. The upper and lower cylindrical members are each provided with two adjacent cylinder-like roller bearings which the two inner rollers contact the arms. The upper roller contacts and is in a groove in the upper cap or top of the housing and the lower roller contacts and is in a groove in the bottom of the housing.
SUMMARY OF THE INVENTION
This is a new method and apparatus for providing lateral support to the block of a Scotch Yoke mechanism which is used in an operator to transfer linear motion of a drive nut into rotational motion. This includes a hub assembly having a hub with a set of upper arms and a matching aligned pair of lower arms. The upper arms and the lower arms each take on a U-shape appearance to have an upper arm slot between each of the upper arms and a lower arm slot between each of the lower arms. There is a vertical displacement between the upper and lower arms and it is through this vertical space between the arms that a drive screw is mounted which extends externally of a housing which covers the entire hub assembly. A drive nut is provided for the screw and has an upper and lower cylindrical bolt-like member. An upper roller is retained on the upper member and a lower roller on the lower member. The upper roller is spaced in the slot between the upper arms and the lower roller is placed in the slot between the lower arms. Each roller has a diameter slightly less than the width of the slot. A housing encloses the Scotch Yoke and associated parts. The whole assembly can be called an operator. The drive screw can be rotated by turning a handle outside of the housing.
A rib is attached to or made a part of the housing and extends between the upper arms and the lower arms and extends essentially the length of that part of the screw which is inside the housing. A vertically extending slot is provided in the rib and is known as a rib slot. It is in this rib slot that the drive nut is placed. The opposite sides of the drive nut contact the walls of this rib slot and absorbs the lateral force exerted on the drive screw. This prevents deformation of the screw. The rib slot can be machined from the rib which can be cast with the housing.
The hub of the hub assembly is attached to a rod or bolt which extends externally of the housing of the operator and is used to rotate whatever might be desired to be rotated by the movement of the hub assembly. Quite frequently, this is used to open and close ball type valves.
Various objects and a better understanding of the invention can be had from the following description taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an operator and a ball type valve to be turned by the operator.
FIG. 2 illustrates the thrust transfer system of the conventional Scotch Yoke.
FIG. 3 is a view taken along the line 3--3 of FIG. 2.
FIG. 4. illustrates the directional force of F R as a function of the force F and angle A.
FIG. 5 is similar to that in FIG. 4 except that angle A equals 0.
FIG. 6 is a graph showing the tort characteristics of a Scotch Yoke for various angular positions.
FIG. 7 is a graph showing the tort requirement of a ball valve as a function of ball position of a typical ball valve.
FIG. 8 is a view of the housing of this invention showing the rib slot which gives lateral support to the drive nut.
FIG. 9 illustrates an exploded view of the yoke assembly including the drive nut and rollers.
FIG. 10 is a cross-sectional view of my invention showing the yoke assembly with the drive nut positioned in the rib slot.
FIG. 11 is a view taken along the line 11--11 of FIG. 10.
FIG. 12 is a top view of the housing of the operator showing a modification of the rib slot of my invention.
FIG. 13 is a view taken along the line 13--13 of FIG. 12.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Attention is first directed to FIG. 1 which shows an operator 10 mounted on top of a valve 12. This illustrates a conventional operator which uses a Scotch Yoke mechanism to convert linear motion into rotary motion as will be explained in conjunction with FIGS. 2 and 3. The operator has a housing as shown in FIGS. 2 and 3 consisting of a top 14 and a bottom 16. As is further illustrated in FIG. 2, there is an upper pair of arms 18 of the Scotch Yoke assembly and a lower pair of arms 20. There is a lower roller slot 22 in bottom 16 and an upper roller slot 24 in cap 14. A drive nut 26 is supported between arms 18 and 20 and is threadedly connected to a drive screw 28 which can be rotated by means of wheel 30 shown in FIG. 1. Drive nut 26 has an upper cylindrical extension 32 and a lower cylindrical extension 34 which extend respectively into upper roller slot 24 and lower roller slot 22. Mounted on upper cylindrical member 32 is a top roller 33 mounted within upper slot 24. There is a roller 36 mounted on lower cylindrical member 34 and it is in lower roller guide 22 which is in the bottom of the housing. Slots 22 and 24 receive the lateral force which is applied to the screw 28 when it is moving the yoke assembly through rotation of arms 18 and 20 by drive nut 26 as will be explained in connection with FIGS. 4 and 5. As shown in FIG. 3, upper arm 18 of the yoke assembly has arms 18A and 18B and the lower yoke arm likewise has arms 20A and 20B.
As the valve wheel 30 of FIG. 1 is rotated, it causes screw 28 as shown in FIGS. 2 and 3 to rotate. Inasmuch as drive nut 26 is threaded to screw 28, as screw 28 rotates, drive nut 26 is moved along in a straight line with the lateral forces being absorbed by the walls of the upper slot 24 and the walls of the lower slot 22 through rollers 33 and 36 respectively. The lateral force is in reality applied to the drive nut 26 and the reaction to this is through the rollers 33 and 36. There are two major problems concerned with this, one is that the screw 28 must accept a considerable amount of the lateral force. By lateral I mean the force that is perpendicular to the longitudinal axis of the screw 28. Another problem with the arrangement in FIGS. 2 and 3 is that the alignment of the slots 22 and 24 must be very precise in order to prevent the build-up of unwanted forces.
Attention is next directed to FIG. 4 which shows the direction and magnitude of the force on roller 33 for example. The longitudinal axis of the screw 28 of FIG. 2 is along the center line 40 of FIG. 4 and the yoke assembly having arms 18A and 18B rotates about center 42 of the hub 44. Hub 44 is connected to a shaft extending externally of the housing to generate a rotary motion from the linear motion of the drive nut 26 caused by the rotating of the screws 28. The direction and magnitude of force F R is a function of the force F and angle A. Force F is generated by the rotation of drive screw 28 and F R is the reaction force on yoke arm 18A as it resists rotation about center 44. If friction is neglected, F R =F/cosA. The moment arm M of F R about the center of 42 of the hub is M=D/cosA. The torque is FR×M or FD/cos 2 A. The number of degrees which arms 18A and 18B can rotate about center 42 is limited theoretically to a maximum of 180° of travel. However, from the expression given for M, it is evident that as A approaches 90°, the length M approaches infinity. This limits the angle A to some value less than 90°. Typically, the angle A varies from -45° to 45°. The graph in FIG. 5 shows that when A=0, F Y =0. When F Y =0 there is no lateral force on screw 28, that is, of course, that force perpendicular to the longitudinal axis of the screw is 0. So, at this mid-point, there is no lateral force on the drive nut.
The graft in FIG. 6 shows the torque characteristics of a typical Scotch Yoke and assumes A varies from -45° to +45°. The actual output of a Scotch Yoke is less than predicted due to the effects of friction.
The mechanical advantage of a Scotch Yoke is a function of A. If the limits of travel of the drive nut are assumed to be 45° and -45°, then the mechanical advantage at either 45° or -45° is twice that at 0°. Note that the equation for the torque, FD/cos 2 A is FD at 0° and FD÷0.5 at -45° and 45°.
The side load on the drive nut 26 is given by Y=FtanA. Y is greatest at the extreme values of A and least 0 when A is 0. As Y increases, the friction induced by Y also increases. The efficiency of a Scotch Yoke is greatest when Y is least and is at a minimum whey Y is largest due to the frictional forces caused by Y. FIG. 7 shows the torque requirement for valve movement of a typical ball valve for different valve openings.
This describes a Scotch Yoke and shows how it functions. This also points out that a disadvantage of the type support as shown in FIGS. 2 and 3 is the difficulty of maintaining precise alignment between the two spaced apart runways 24 and 22. Also, as pointed out briefly above, if there is a large distance between the roller 33 and roller 36, then the lateral force exerted on the drive nut must, in part, be transferred to the screw 28. There may also be deformation of screw 28 which can be detrimental.
Attention is now directed to my improvement in the operator having the Scotch Yoke assembly whereby I eliminate the problems of the conventional assembly discussed above. I remove the problems of having to accurately machine the lower and upper slots 22 and 24 which are in the housing proper. I replace those two slots with a single slot. I also provide a system where the guide screw 28 does not have to carry side loads. Attention is directed to FIG. 8 showing the modification of the housing which I have provided. Shown therein, is a housing 50 with top and bottom removed and showing a rib 52 therein. Rib 50 has a rib slot 54 which, as will be seen when it is assembled, is between the upper and lower arms 18 and 20 as shown in FIG. 10. Rib slot 54 is aligned with drive screw 56 which enters through opening 58. Screw 56 extends through the other end of rib slot 54 through hole 60. Rib 52 can be cast without the rib slot 54 and then rib slot 54 can be machined. It is noted that there is only one slot to machine in this arrangement so there is no problem about alignment with a second slot. I also do away with the upper and lower rollers 33 and 36 as shown in FIG. 2. As shown in FIG. 9, I have a drive nut 62 having internal threads 64 through which screw 56 rotates. The drive nut also has an upper cylindrical member 66 and a lower cylindrical member 68. An upper roller 70 is held in position over the nut of the cylindrical extension 66 by snap ring 72, likewise, the lower roller 74 can be held in position on cylindrical extension 68 by snap ring 76. Opening 75 can also be provided in housing 50 as shown in FIG. 8 so that serts or other type fittings can be attached thereto so that grease can be applied to the internal part of the housing.
Attention is now directed to FIGS. 10 and 11 which shows the housing 50 previously shown in FIG. 8, as having a top 80 and a lower end or bottom 82. The improved Scotch Yoke assembly has been inserted into the housing. As shown in FIG. 10, the drive nut 54 mounted on drive screw 56 is mounted within rib slot 54. The rollers 70 and 74 are in contact with the arms 18 and 20. The drive nut 62 is in contact with the walls 55 and 57 of the rib slot 54. With this system, the screw 56 cannot be bent by lateral force because the rib slot wall holds the drive nut in position.
It is believed apparent that there are many advantages to the rib slot support system which I have described herein. There is no misalighment problem between top and bottom slots of the housing in the convention system because I have only one slot in my system. It is a further advantage to have to machine only one slot instead of two. The rib onto which the slot is cut is an intergal part of the housing and the rib itself is quite stiff. The screw 56 does not carry any side or lateral loads.
In the device of FIG. 10, the shaft 83 is inserted into the hub 81 of the yoke assembly as shown in FIG. 9 and is prevented from rotating by placing a locking pin in slot 77. Shaft 83 extends out the lower end of the housing and can be used to rotate a ball valve such as is shown in FIG. 1. Also, in FIG. 11, screw 56 has extension 57 which may be attached to a hand wheel or other drive mechanism. To assemble this device, the yoke assembly proper shown in FIG. 9 including the arms 18 and 20 and hub 81 are lowered through opening 94 as shown in FIGS. 8 and 12 with the center of the yoke 79 at the center of the housing. After the yoke is lowered down to the proper position so that the upper arms are above rib 52 and the lower arms are below it. The drive screw 56 and its associated drive nut 64 and rollers 70 and 74 are then assembled in rib slot 54 with drive nut 62 in the position shown in FIG. 10. The yoke assembly is then manipulated and rotated so that the upper slot 19 of arm 18 and the corresponding lower lost of the lower arms 20 is positioned about rollers 70 and 74 as shown in FIG. 11.
Attention is now directed to FIGS. 12 and 13 which show a slight modification of my invention. The rib slot 54 is provided with a pair of "dimples" 90 and 92. The purpose of this is to ease assembly and disassembly. As explained above, when the drive nut 64 is in the center position where angle A=0, there is no side force. Therefore, I can make the dimples 90 and 92 as shown in FIG. 12 without having to worry about how the side force is transferred, because there is none. The reason that these dimples have importance is that sometimes the roller 74 might become slightly deformed and have trouble extracting it. However, the dimples 90 and 92 would permit easy removal because the rollers would probably be only slightly deformed.
While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled. | This is a system of providing lateral support to the block of a Scotch Yoke mechanism. The Scotch Yoke mechanism is useful in operators or devices which translate linear motion to rotary motion. The Scotch Yoke has a hub with an upper U-shaped member having two arms and a lower U-shaped member also having two arms. The hub is connected to a rod so that rotation of the hub rotates the rod. A drive screw or rod is between the upper and lower U-shaped arms and is provided with a block which has upper and lower rollers for engaging the Scotch Yoke assembly which is mounted in a housing. This whole mechanism may be called an operator. A new and improved way is provided for transmitting applied force which is imposed on the block to the housing proper. | 5 |
This application claims priority of international application PCT/IB99/00134 filed Jan. 26, 1999 with priority of RU 98101488 filed Jan. 27, 1998.
BACKGROUND
The invention pertains to the field of jet technology, primarily to pumping-ejection systems for producing a vacuum.
A pumping-ejection system is known, which has a liquid-gas ejector and a pump. The gas inlet of the ejector is connected to a source of an evacuated gaseous medium, the liquid inlet—of the ejector is connected to the discharge side of the pump, an outlet of the ejector is connected to a drainage system (see “Jet Apparatuses”, book of E. Y. Sokolov, N. M. Zinger, “Energia” Publishing house, Moscow, 1970, page 215).
The main imperfection of this system is its low efficiency.
The closest analogue of the system introduced in the present invention is a pumping-ejection system having a vacuum separator, a pump, an inlet liquid-gas ejector, a discharge liquid-gas ejector and an outlet separator, wherein the suction side of the pump is connected to the liquid outlet of the vacuum separator, the gas inlet of the inlet ejector is connected to a source of an evacuated gaseous medium, the liquid inlet of the inlet ejector is connected to the discharge side of the pump, an outlet of the inlet ejector is connected to the vacuum separator, the gas inlet of the discharge ejector is connected to the gas outlet of the vacuum separator, an outlet of the discharge ejector is connected to the outlet separator (see RU, patent, 2084707, cl. F 04 F 5/54, 1997).
This pumping-ejection system is intended for producing and maintaining a vacuum, mainly in rectification columns. More intensive operation of the system is achieved because the system incorporates two self-contained stages of evacuation. However, this arrangement with the two self-contained stages of evacuation has some shortcomings: the operational pressure within the second stage is higher than the operational pressure within the first stage, therefore a liquid medium circulating in the second-stage circulation loop is saturated with a solute gas more intensively if compared with a liquid medium circulating in the first-stage circulation loop. Continuous employment of a motive liquid saturated with a gas reduces the efficiency of the second-stage ejector and results in an increase in the energy consumption for providing the required flow rate of gases evacuated from the vacuum separator. Additionally, two independent loops of the motive liquid circulation require two independent pumps for delivery of the motive liquid to the ejectors inlets. This makes transfer of the motive liquid from one circulation loop to another more complex.
SUMMARY OF THE INVENTION
The present invention is aimed at attaining more economical operation of the system due to employment of a motive liquid with minimal content of a solute gas in all of the system's evacuation stages.
This objective is achieved as follows: a pumping-ejection system, which has a vacuum separator; a pump connected through its suction port to the vacuum separator; an inlet liquid-gas ejector, whose gas inlet is connected to a source of an evacuated gaseous medium, liquid inlet—is connected to the discharge side of the pump and whose outlet is connected to the vacuum separator; an outlet separator, a discharge liquid-gas ejector, whose gas inlet is connected to the vacuum separator and whose outlet is connected to the outlet separator; is furnished further with a pipe for liquid tapping, which connects the outlet separator with the vacuum separator, and the liquid inlet of the discharge ejector is connected to the discharge side of the pump. The pumping-ejection system can be furnished with an outlet liquid-gas ejector and with a final separator. In this case the gas inlet of the outlet ejector is connected to the outlet separator, the liquid inlet of the outlet ejector is connected to the discharge side of the pump, an outlet of the outlet ejector is connected to the final separator, and the liquid outlet of the final separator is connected to the vacuum separator. In addition, the system can be furnished with a heat exchanger-cooler installed at the suction side of the pump.
It was determined, that the condition of a motive liquid being fed by the pump into the nozzles of the liquid-gas ejectors through their liquid inlets, exerts a significant influence on the performance the of the pumping-ejection system as a whole. The main factor which affects the condition of the motive liquid most of all is the content of a solute gas in the motive liquid.
As it was noted above, in the prototype pumping-ejection system a motive liquid is fed from the outlet separator into the second-stage liquid-gas ejector under a pressure, which is higher than a pressure maintained in the vacuum separator, and this is the cause of a lower capacity of the second-stage ejector. This effect is explained by the fact that the motive liquid always contains a certain quantity of a solute gas and emission of the solute gas from the motive liquid occurs when pressure in the ejector receiving chamber becomes equal to the saturation pressure of the solute gas. Therefore the ejector gas capacity decreases, because, together with an evacuated gaseous medium, the ejector must evacuate the gas evolved from the motive liquid.
In the pumping-ejection system described in the present invention, a motive liquid is fed into the nozzles of all ejectors from the vacuum separator, because prior to feeding the motive liquid into the nozzles of appropriate ejectors, the motive liquid from the separators of the consequent stages is transferred into the vacuum separator, where the lowest pressure is maintained and where the liquid is degassed most effectively. Thus, the motive liquid degassed under a lowest possible pressure is fed into the nozzles of all ejectors. As compared with the prototype system, the pumping-ejection system of the introduced layout ensures a higher gas capacity or less energy consumption in view of equal gas capacity.
Thus, a more economical operation is provided by the described system.
BRIEF DESCRIPTION OF THE DRAWING
A schematic diagram of the described pumping-ejection system is presented in the drawing.
DETAILED DESCRIPTION
The pumping-ejection system has a vacuum separator 1 , a pump 2 whose suction side is connected to the vacuum separator 1 , an inlet liquid-gas ejector 3 whose gas inlet is connected to a source 4 of an evacuated gaseous or gas-vapor medium, liquid inlet is connected to the discharge side of the pump 2 and outlet is connected to the vacuum separator 1 , and a discharge liquid-gas ejector 5 whose gas inlet is connected to the vacuum separator 1 and outlet is connected to an outlet separator 6 . The outlet separator 6 is furnished with a pipe 10 for liquid bleeding, which connects it to the vacuum separator 1 . The liquid inlet of the discharge ejector 5 is connected to the discharge side of the pump 2 .
In addition, the system can be furnished with a third stage of evacuation including an outlet liquid-gas ejector 7 and a final separator 8 . In this case the gas inlet of the outlet ejector 7 is connected to the outlet separator 6 , the liquid inlet of the outlet ejector 7 is connected to the discharge side of the pump 2 , an outlet of the outlet ejector 7 is connected to the final separator 8 , the liquid outlet of the final separator 8 is connected by a pipe 11 to the vacuum separator 1 . The system can be furnished also with a heat exchanger-cooler 9 installed between the vacuum separator 1 and the suction side of the pump 2 .
The pumping-ejection system operates as follows.
The pump 2 delivers a motive liquid, for example water or a hydrocarbon liquid, into the nozzles of the liquid-gas ejectors 3 , 5 through their liquid inlets. The motive liquid flowing out of the nozzle of the inlet ejector 3 evacuates a gaseous or gas-vapor medium from the source 4 (the latter can be a rectification column, for example). The motive liquid mixes with the evacuated gaseous medium in the inlet ejector 3 . Under certain conditions, for example when the evacuated medium contains some easy-condensable components, partial or complete condensation of the condensable components in the motive liquid can take place. At the same time the evacuated gaseous medium undergoes compression in the ejector 3 due to energy transfer from the motive liquid. A gas-liquid mixture flows from the inlet ejector 3 into the vacuum separator 1 , where the motive liquid is separated from the evacuated gas. As a rule, condensation of the easy-condensable components of the evacuated gas in the motive liquid is completed in the vacuum separator 1 . The gas separated from the motive liquid in the vacuum separator 1 is evacuated by the discharge ejector 5 . So, a required vacuum is maintained in the vacuum separator 1 . The motive liquid flowing out of the nozzle of the discharge ejector 5 evacuates the gas from the vacuum separator 1 and compresses it at the same time. A gas-liquid mixture formed in the discharge ejector 5 flows into the outlet separator 6 , where the compressed gas is separated from the motive liquid. Then the compressed gas is delivered to consumers or is further utilized as discussed below. The motive liquid from the outlet separator 6 passes through the pipe 10 into the vacuum separator 1 , where it is degassed prior to feeding into the nozzles of the ejectors 3 , 5 . Because pressure in the outlet separator 6 is higher than pressure in the vacuum separator 1 , the motive liquid can flow from the outlet separator 6 to the vacuum separator 1 by gravity, though in some cases a pump (not shown) can be used for the motive liquid transfer from the outlet separator 6 to the vacuum separator 1 .
When a high-pressure gas is required for consumers, the system can be additionally furnished with a third stage of evacuation including the outlet liquid-gas ejector 7 and the final separator 8 . Generally, the number of the system stages can exceed three, if necessary. In this case additional stages are connected in series in the same way as described for the third stage. So, if it is necessary, the outlet ejector 7 evacuates the compressed gas from the outlet separator 6 . The motive liquid flowing out of the nozzle of the outlet ejector 7 additionally compresses the evacuated compressed gas. A gas-liquid mixture from the outlet ejector 7 flows into the final separator 8 , where the motive liquid is separated from the additionally compressed gas. The additionally compressed gas from the final separator 8 is delivered to consumers, the motive liquid from the final separator 8 is delivered to the vacuum separator 1 through a pipe 11 for degassing of the motive liquid. Then the liquid is fed by the pump 2 into the ejectors 3 , 5 , and 7 . Because the motive liquid can be warmed during operation of the pumping-ejection system, the system can be equipped with the heat exchanger-cooler 9 for cooling the motive liquid.
Subject to specific operational conditions an additional quantity of the motive liquid can be fed into the vacuum separator 1 , or a surplus liquid (for example, in case of accumulation of a large amount of condensate) can be removed from the vacuum separator 1 .
Industrial Applicability: This invention can be applied in chemical, petrochemical, agriculture and some other industries. | A pumping-ejection system has a vacuum separator, a pump connected through its suction port to the vacuum separator, an inlet liquid-gas ejector, a discharge liquid-gas ejector and an outlet separator. The outlet separator is furnished with a pipe for liquid tapping, which connects the outlet separator to the vacuum separator. The liquid inlet of the discharge ejector is connected to the discharge side of the pump. The introduced pumping-ejection system requires lower power inputs for its operation. | 5 |
FIELD OF THE INVENTION
[0001] This invention relates to a method and apparatus for verifying the integrity of a computer security subsystem for preventing attacks on computer network security systems.
BACKGROUND OF THE INVENTION
[0002] Concurrent with the rise in connectivity among diverse computer networks and the corresponding increase in dependence on networked information systems, there has been a dramatic increase in the need for robust security to enforce restrictions on access to and prevent intrusion on secure systems. The topology of the interconnected networks has also grown increasingly complex, and often involves open networks such as the internet that expose secure systems to increased threats of attack. Consequently, no single solution has yet been proposed that addresses all current needs for intrusion detection and response. Instead, a vast assortment of security devices and techniques has evolved and has generally been implemented differently on individual systems. This has resulted in a global security patchwork, inherently susceptible to attack and to individual systems which themselves implement a hodge podge of different security devices and techniques.
[0003] Attempts to gain unauthorized access to computer networks capitalize on inherent loopholes in a network's security topology. It is known, for example, that although a secure system connected to the internet may include firewalls and intrusion detection systems to prevent unauthorized access, weaknesses in individual security components are often sought out and successfully exploited. The rapid introduction of new technology exacerbates the problem, creating or exposing additional weaknesses that may not become known until a breach in security has already occurred.
[0004] A fundamental weakness shared in common by current intrusion detection and response systems is their “flat” or non-hierarchical implementation. The configuration shown in FIG. 1 is an example of such a typical network implementation on a hypothetical “target network”. The network 10 includes a plurality of file servers 14 , workstations 16 , a network intrusion detection system (IDS) 18 , a remote access server 20 and a web server 22 . These devices are connected to each other over network backbone 12 , and form a local or wide-area network (LAN or WAN). Router 26 is connected directly to an open network such as the internet, 30 , and is connected to the devices on network backbone 12 through network firewall 24 .
[0005] The firewall 24 and the IDS 18 are part of the security system of network 10 . Firewall 24 is configurable and serves to control access by hosts on the internet to resources on the network. This protects network 10 from intruders outside the firewall, essentially by filtering them out. IDS 18 scans packets of information transmitted over backbone 12 and is configured to detect specific kinds of transactions that indicate that an intruder is attempting, or already has gained access to the network, 10 . In this way, the IDS protects the network from intruders inside as well as outside the firewall. Other devices on network 10 may also contribute to network security, such as remote access server 20 which permits access directly to network 10 from remote computers (not shown), for example over a modem. Remote access server 20 must also implement some security function such as username and password verification to prevent intruders from gaining access to the network and bypassing firewall 24 .
[0006] In a typical intrusion scenario on a target network connected to the internet, an intruder will first learn as much as possible about the target network from available public information. At this stage, the intruder may do a “whois” lookup, or research DNS tables or public web sites associated with the target. Then, the intruder will engage in a variety of common techniques to scan for information. The intruder may do a “ping” sweep in order to see which machines on the target network are running, or they may employ various scanning utilities well known in the art such as “rcpinfo”, “showmount” or “snmpwalk” to uncover more detailed information about the target network's topology. At this stage the intruder has done no harm to the system, but a correctly configured network IDS should be able, depending on its vantage point on the network, to detect and report surveillance techniques of intruders that follow known patterns of suspicious activity. These static definitions, known as “intrusion signatures”, are effective only when the intruder takes an action or series of actions that closely follow the established definitions of suspicious activity. Consequently, if the IDS is not updated, is disabled or encounters an unknown or new method of attack, it will not respond properly. However, if steps are not taken at this point in the attack to prevent further penetration into the target network, the intruder may actually begin to invade the network, exploiting any security weaknesses (such as the IDS that may not have reacted earlier to the intruder), and securing a foothold on the network. Once entrenched, the intruder may be able to modify or disable any device belonging to the target network including any remaining IDS or firewall.
[0007] Methods used by intruders to gain unauthorized access to computer networks evolve in sophistication in lock step with advances in security technology. It is a typical, however that successful attacks on network systems often begin by attacking the security subsystems in place on the target network that are responsible for detecting common intrusion signatures, disabling those systems and destroying evidence of the intrusion.
[0008] U.S. Pat. No. 5,916,644 to Kurtzberg et al. discloses a method for testing the integrity of security subsystems wherein a specially configured system connected to directly a target computer network will systematically test security on the network by simulating attacks on security devices in order to verify that they are operational. Specifically, the disclosed method randomly simulates an attack on the network. If the attack is detected, the security subsystems are assumed to be functioning. If not, they are considered compromised, and an attack may already be underway. This method is an improvement over passive systems that do not check themselves and therefore cannot properly report on their own status when they have been disabled.
[0009] A major shortcoming of this approach is that these security systems reside on the same networks that they seek to protect and are similarly vulnerable to attack once an intruder has gotten a foothold on the network. In other words, they are not themselves immune to the attacks of intruders. As a result each advance in the prior art is just another new security hurdle on the network to be defeated. In this light, the active scanning approach disclosed in Kurtzberg is not fundamentally different from any other security measure (such as a firewall) in that it is non-hierarchical and depends completely on the vigilance of a human network manager.
[0010] Therefore, there exists a need for a self-diagnosing network security system that can protect a target network from both internal and external intruders and that is resistant to attacks perpetrated on the system it has been deployed to protect. Furthermore, there is a need for an active security system that will take measured action against perceived security threats even in the absence of a human network manager.
SUMMARY OF THE INVENTION
[0011] It is therefore an object of the present invention to provide a network security system for a network of computers that is capable of solving the above mentioned problems in the prior art.
[0012] It is another object of the present invention to provide a network security system that has a component that can directly monitor multiple network security devices on a network for attack signatures and other suspicious network activity suggesting an attempt to compromise security on that network.
[0013] It is another object of the present invention to provide a network security system that can dynamically detect new patterns or trends in network activity that suggest an attempt to compromise network security on a single network or on a plurality of otherwise unrelated networks.
[0014] It is another object of the present invention to provide a network security system that can resist intrusion during an attack on the network.
[0015] It is another object of the present invention to provide a security system providing integrity verification for security devices on a network, and can also reliably verify its own integrity.
[0016] It is another object of the present invention to provide a security system for a computer network that can take corrective measures after an attack has been detected to prevent an intruder from gaining further access to the network.
[0017] It is another object of the present invention to provide a security system satisfying the above objectives for individual computers connected to an open network.
[0018] According to an example of the present invention, there is provided a network security system to prevent intrusion on a target network having at least one security subsystem local to the target network provided to monitor network traffic and to detect attacks by an intruder on the system. The subsystem is connected via a secure link to a master system that is not otherwise connected to the target system. The master system monitors the subsystem via the secure link and registers information pertaining to the status of the subsystem. If the subsystem detects an attack on the target network, or does not respond to the master system, the master system will take appropriate action, ranging from logging the incident or notifying a network manager to attempting to shut down the network. Accordingly, even attacks that completely disable the subsystem will not prevent the master system from responding as long as the link remains secure.
[0019] According to another example of the present invention, a multi-level hierarchy is implemented making the subsystem subordinate to the master system. In this configuration, commands can only be passed from the master system to the subsystem, ensuring that the integrity of the master system can not be undermined, even by successful attacks on the target network, or on the subsystem itself. Therefore, even a subversion of the subsystem and a compromised link between it and the master system is insufficient to disable the master system.
[0020] According to another example of the present invention, a pseudo-attack generator associated with the master system is provided that simulates attacks on the target network that should be detected by the subsystem. By comparing the pseudo-attacks made on the target network to the attacks actually detected by the subsystem, the master system can determine whether the integrity of the subsystem has been compromised. Similarly, the subsystem may generate its own pseudo-attacks on other network security components to establish their integrity as well. Therefore it is possible to test comprehensively every security-related device connected to the target network.
[0021] In another example of the present invention, the subsystem, and the master system acting through the subsystem, can implement corrective measures to mitigate or thwart suspected intruder attacks on the target network.
BRIEF DESCRIPTION OF THE DRAWINGS:
[0022] [0022]FIG. 1 is a block diagram showing the overall structure of an example of a network system according to the prior art.
[0023] [0023]FIG. 2 is a block diagram showing an example of a network incorporating the system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] The preferred embodiments of a network security system according to the present invention will hereinafter be described with reference to the accompanying drawings.
[0025] Referring to FIG. 2, a first embodiment of the present invention is shown. Target network 100 is shown having the same basic components as the network of the prior art shown in FIG. 1 with the addition of security subsystem 50 , however it should be noted that the actual configuration of the target network is not critical with the exception of at least one security subsystem 50 . Each of the security subsystem 50 , servers 14 , workstations 16 , IDS 18 , remote access server 20 , web server 22 , firewall 24 and router 26 are connected together over network backbone 12 . Each of the devices carry out communication over the backbone in accordance with a predetermined communication protocol such as Transmission Control Protocol/Internet Protocol (TCP/IP).
[0026] Target network 100 is connected through firewall 24 and router 26 to the internet 30 as well as through remote access server 20 which may also be selectively connected to the internet 30 through remote user 21 . These two potential points of contact with an open network, in this case the internet, exposes target network 100 to the threat of intrusion from any host with access to the internet such as internet user 31 . In addition to threats from the outside, those with direct access to the resources of target network 100 , such as those using one of the workstations 16 , also pose an intrusion threat. If an intruder were to gain access to one of the critical security-related devices such as the IDS 18 or the firewall 24 or any trusted computer from within or outside the target network 100 , security on the network could be compromised.
[0027] In the present invention, security subsystem 50 is connected to network backbone 12 and linked to each of the network's devices by a secure link 52 . Such a secure link may be established through an encrypted communication protocol such as Secure Sockets Layer (SSL). This ensures that communication between the security subsystem 50 and the other components of the target network cannot be intercepted by an intruder. A similar secure link 54 is established as a virtual private network (VPN) tunnel between the security subsystem 50 and a master system 60 connected to a remote network 110 . Although the remote network is shown having its own firewalls 62 , servers 66 , and router 68 , the ultimate configuration of remote network 110 is not critical beyond secure link 54 connecting security subsystem 50 and master system 60 . However, secure links 55 may be established between a device such as a network scanner 63 and a router 26 or remote user 21 on network 100 . Secure link 54 ensures that communication between the two networks cannot be intercepted by an intruder. Therefore, there should be no other direct connection between target network 100 and remote network 110 except over a secure link.
[0028] Preferably, the security system defined herein is embedded as a software package and implemented on computers comprising at least a master system and the security subsystem.
[0029] During operation, security subsystem 50 monitors the activities of the devices of the target network 100 . Particularly, the critical security-related functions of IDS 18 and firewall 24 are tested. The particular method employed by security subsystem 50 in testing these devices is not critical, however the above mentioned approach employing simulated attacks on the components would be suitable.
[0030] Upon testing the devices, if the integrity of a device on target network 100 cannot be verified, security subsystem 50 reacts. For example, if IDS 18 has been identified by the subsystem as not reacting properly to attacks on it originating from the internet, appropriate countermeasures could include cutting off or restricting access to the network at firewall 24 or stop at application level. If instead, the firewall is determined not to be functioning, appropriate action might include disabling access to any servers 14 holding sensitive data. In one possible configuration of the present invention, security subsystem 50 reports network device status to master system 60 which processes the information, and decides on further action. In an alternate configuration, security subsystem 50 is responsible for implementing countermeasures directly. In both cases, however, the results of every test are passed to master system 60 where they are stored for analysis.
[0031] The system of the present invention can also help thwart ongoing attacks and is uniquely suited to do so. In another preferred embodiment of the present invention, master system 60 hierarchically supercedes security subsystem 50 . As such, the activities of security subsystem 50 are defined as a child process of master system 60 and are subordinate thereto. Although information preferably flows both ways between master system 60 and security subsystem 50 in this embodiment, the master system in this embodiment does not take direction from the subsystem.
[0032] As noted in the discussion of the prior art, non-hierarchical security systems are connected directly to a target network and are inherently susceptible to attacks on that network. This is in contrast to the present embodiment wherein, even if completely subverted during an attack on target system 100 , security subsystem 50 would not result in a takeover of master system 60 . The benefit of this configuration is that the master system would still be able to carry out its function. For example, if master system 60 is configured to sound an alarm when security subsystem 50 no longer responds to it, there would be no way, in this embodiment, for intruders on target network 100 to remotely shut down master system 60 because the master system will not respond to any instructions issued from a subordinate system. Although master system 60 may lose control of the target network, it is not in danger of being taken over by it. Additionally, if the link 54 between master system 60 and security subsystem 50 is severed or compromised, instructions may be routable instead through secure links 55 .
[0033] In yet another embodiment of the present invention, remote network 110 is connected through router 70 to an open network such as the Internet. This enables master system 60 to send random pseudo-attacks to target network 100 . The pseudo-attacks may mimic any of the actual attack signatures known by the master system to be detectable by the target network. If the expected reply is not received by the master system, an early indication of an intruder attack on the target network is indicated.
[0034] As set forth hereinabove, according to the present invention, it is possible to provide a method and apparatus for verifying the integrity of computers and computer networks that is independent of the network or computer being tested. In addition, by detecting early signs of intruder activity on a network, the present invention increases the likelihood that intruder attacks can be thwarted before they succeed.
[0035] When implemented on an individual computer, such as a single workstation 16 connected to an open network such as internet 30 , the present invention functions similarly to prevent attacks on that computer originating from the open network. In the absence of network backbone 12 the functions of security subsystem 50 may be directly incorporated into an individual computer such as by software or peripheral hardware.
[0036] When implemented across a plurality of otherwise unrelated target networks, the present invention functions to prevent attacks according to the methods described herein on each target network individually. The advantage of this configuration is that security information may be coordinated across several networks without connecting the networks together.
[0037] Many different embodiments of the present invention may be constructed without departing from the spirit and scope of the invention. It should be understood that the present invention is not limited to the specific embodiments described in this specification. To the contrary, the present invention is intended to cover various modifications and equivalent arrangements included within the spirit and the scope of the claims. | A method and apparatus for verifying the integrity of devices on a target network having two components: a subsystem connected to the target network, and a master system, isolated therefrom by a secure link. The topological and hierarchical relationship of the of the devices to each other improves stability of the apparatus. Random testing of target network devices by the subsystem and random testing of the subsystem by the master system provide verification and independent self-checking. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates generally to sewing machines having an electric drive and a foot control for regulating the sewing speed and for selecting at least one needle stop position and more specifically to sewing machines wherein the foot control has a range of regulation for which regulating signals for determining the sewing speed are produced, and an off position for which a switch off signal, different from the regulating signals, is produced. A receiver for these signals is provided, which when it receives an off signal, operates to control the needle in one of the stop positions.
Such a sewing machine is described in PCT-Application WO No. 82/03 879. This known machine is relatively simple because it is provided with an usual foot control with a variable resistance and a circuit breaker at one of its end positions. However, the foot control described has an important drawback in that to reverse the position of the needle between its upper stop position, which it assumes automatically when the machine is stopped, and the bottom stop position, or from the bottom stop position to the upper stop position, the foot control must be brought into its control position for only a short time interval. Such position reversals are difficult, particularly for unpracticed persons.
It is therefore an object of the present invention to produce and to transmit additional control signals between a foot control and a sewing machine. It is a further object of the present invention to simplify a control for a sewing machine and to provide a more versatile sewing machine control.
SUMMARY OF THE INVENTION
In accordance with the present invention a foot control is provided which is commutable between at least one control position in which it produces a control signal, different from regulating signals and a switch off signal. Preferably a receiver associated with the foot control, comprises at least two logic input circuits which define at least three determined logic conditions, each logic condition determining a function. Advantageously, only a two wire connection for the transmission of all signals is necessary between the foot control and the receiver.
With at least three logic conditions e.g. 1/1, 1/0, 0/0, the input circuits of the receiver can control well determined functions of the machine without the requirement of having to maintain a determined sequence of these functions or of having to activate, for a short time interval, the foot control for releasing a determined function.
Preferably a foot control is provided comprising a means for holding a pedal in a control stopping position and for permitting a horizontal swing of the pedal in a forward direction to switch on a variable resistance for producing a regulating signal, or in a backward direction into a control position for producing the control signal. The pedal may work on a slide with brushes which may run from the stopping position at one side upon layers of a variable resistance and at the other side on contacts for closing a control circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described further by means of an example and with reference to the accompanying drawings in which similar elements are identified with the same numerals and in which:
FIG. 1 shows a preferred embodiment of an electric circuit diagram;
FIGS. 2 and 3 show respectively the foot control in its off position and in its active position for selecting the stop position of the needle;
FIG. 4 shows the electric parts of the foot control;
FIG. 5 shows a position encoder;
FIG. 6 shows a stopping device for stopping the needle in its upper stop position; and
FIG. 7 shows a second embodiment of the circuit of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows schematically the electric circuit of a foot control 1. These circuits comprises a change-over switch 2 which may alternately connect into the circuit a variable resistance 3 or a fixed resistance 4. In the present embodiment, the variable resistance 3 has a maximum value of 4 kOhm and the resistance 4 a value of 10 kOHm. The electric circuit of the foot control 1 is connected by a two wire cable 5 with a control circuit or receiver 6 which may be disposed in the sewing machine. The circuit of the foot control 1 is supplied with a positive potential by means of a resistance 7. In operation, the resistance 7 forms a voltage divider with either the resistance 3 or the resistance 4 and the voltage at the central point of this voltage divider is delivered to one input of each of the differential amplifiers or comparators 8 and 9 and to an input of a pulse modulator 10. The output of the pulse modulator 10 is connected to one input of an AND gate 11 which is connected to the base of a transistor 12 which in turn controls energization of a driving motor 13 in a chopper mode. The comparators 8 and 9 receive, from a voltage divider comprising resistances 14, 15, 16, different reference voltages. The output of the comparator 8 is connected, through a differentiating circuit 17 and a diode 18, with a capacitor 19. The output of the differentiating circuit 17 as well as the output of the comparator 9 are connected to inputs of a flip-flop 20, the output of which is connected to an input of a NAND gate 21. The output of this NAND gate is connected through a diode 22 with the capacitor 19. The output of the comparator 9 is also connected, through a diode 23 and a parallel resistance 24, to the capacitor 19. This capacitor 19 may be discharged by a resistance 25 and a switch 26. The switch 26 is closed when the upper shaft of the machine is stopped in a position corresponding to the upper stop position of the sewing machine needle as described below. The capacitor 19 is connected, through a Schmidt trigger 27 and an inverter 28, with another input of the AND gate 11. The outputs of the Schmidt trigger 27 and the comparator 9 are connected to NOR gate 29, the output of which drives a stopping magnet 30 for stopping an upper shaft of the sewing machine needle as described below. A photodetector 31, preferably comprising a photodiode and a phototransistor, is connected to another input of NAND gate 21. The control of this photodetector is explained below.
FIG. 2 shows an exemplary foot control 1 for use in the circuit of FIG. 1. The foot control 1 comprises a frame 32 in which a pedal 33 and a lever 34 are slewably mounted on a shaft 33a. Stop tappets 35a and 35b on the pedal determine the end positions of the horizontal swing of the pedal 33 in the clockwise and counter-clockwise directions respectively. A tension spring 36 is positioned between a free end of the lever 34 and the pedal 33. This spring 36 acts to hold the lever 34 in contact with a tappet 37 on the pedal 33. A compression spring 38 is positioned between the bottom of the frame 32 and the lever 34. This spring 38 tends to hold the pedal 33 in a neutral position, as shown in FIG. 2, in which the free end of the lever 34 is in contact with a stop 39 of the case 32. The pedal 33 is supported by the base 32 via a slip connection 40 and a slide 41 by means of which the pedal 33 may be shifted in a vertical direction along guides 41a. This slide 41 is schematically illustrated in FIG. 4. As illustrated in FIG. 4, the slide 41 preferably supports two spring loaded brushes 42. These brushes are pressed against a thick film substrate 43 comprising conducting tracks 44 with contacts 45. The resistance 4 and the two resistive layers 3 respectively corresponding to the resistor 4 and variable resistor 3 of FIG. 1 are disposed in the conducting tracks 44. In the position illustrated in FIG. 4 the brushes 42 are between the resistive layers 3 and the If the slide 41 with the brushes 42 is shifted upward, the brushes 42 contact the contacts 45 which switches the resistance 4 into the circuit. Displacment of the brushes 42 downward causes the brushes 42 to contact the resistive layers 3, thereby switching the resistance 3 of FIG. 1 into the circuit. The resistance value of resistance 3 varies with the vertical position of the slide 41 which carries the brushes 42.
FIG. 5 shows the position encoder. A cam 47 with tappet 48 is fixed on an upper shaft 46 of the sewing machine. The cam 47 acts on a lever 50 slewable around a shaft 49. The lever 50 is pressed against the cam by a tension spring 51. The free end of the lever 50 is preferably in form of a light barrier 52 which in the illustrated position interrupts a light ray of the photodetector 31. If the lever 50 is swung clockwise by the tappet 48, the light barrier 52 opens and a phototransistor in the photodetector 31 becomes conducting.
FIG. 6 shows schematically the stopping device for determining the stop position of the upper shaft 46 of the sewing machine needle. A pulley 53 which drives the upper shaft 46 is mounted thereon by means of a spring coupling. A stopping device of this kind is described in DE-OS No. 30 17 176. A sleeve with a stopping tappet 54 is disposed over the coupling. A stopping lever 55 may be pivoted on a pin 56 into the path of the stopping tappet by means of a magnet 30 in order to stop the upper shaft 46 in a predetermined position. At this predetermined position, the needle is in its upper position over the sewing material and the thread lever is also in its uppermost position. When the stopping tappet 54 comes in contact with the stopping lever 55, the latter is displaced to the right, as viewed in FIG. 6, with respect to the pin 56 against the action of a tension spring 57 until it actuates a switch 26. The above-described mechanism works as follows:
For sewing, the pedal 33 is swung forward to thereby pivot in the clockwise direction of FIG. 2 so that the slide 41 moves downward and the brushes come in contact with the layers of the resistance 3. The value of the resistance has maximum 4 kOhm so that a relatively small voltage appears at the inputs of the comparators 8 and 9. The two comparators then produce a positive output signal. The capacitor 19 is charged through the diode 23. The Schmidt trigger 27 is switched on and a signal is inputted to gate 11 through the inverter 28, so that the pulses of the pulse modulator 35 are delivered to the transistor 12 and the motor 13 is driven. The length of the pulses increases when the input signal decreases and the number of turns of the motor increases. If the foot control is let loose, it comes back to its neutral position illustrated in FIG. 2 and the driving circuit is interrupted. The voltage at the inputs of the comparators 8 and 9 increases to the full voltage, i.e., to a value above the reference voltages and the outputs X and Y of the two comparators go to zero, thus discharging the capacitor 19 through the resistance 24. The time delay which results from the discharge of the capacitor 19 is utilized for further driving the upper shaft and for positioning it so that the needle comes to rest over the sewing material. At the same time the stopping magnet 30 is activated through the gate 29. As described above, the upper shaft is then secured in a predetermined stopping position and at the same time the switch 26 is closed. This produces a rapid discharge of the capacitor 19 through the resistance 25 and the gate 11 is blocked through the Schmidt trigger 27 and the inverter 28 so that the transistor 12 is blocked and the motor 13 receives no current. After the discharge of capacitor 19, the stopping magnet 30 is switched out by the Schmidt trigger 27 and the gate 29.
When the sewing machine is stopped by releasing the foot control, the needle is automatically stopped in its upper position. It could however be desired in some instances, e.g., for turning the sewing material or before the beginning of the operation of sewing, to introduce the needle into the sewing material, that is to displace the needle to its bottom position. To this end the foot control 33 is actuated backwards in the counter-clockwise direction to the stopping position of FIG. 3. The foot control is then lifted off from the lever 34 against the action of the spring 36, the slide 41 with its brushes is displaced upward until the brushes 42 contact the contacts 45. This switches in the curcuit having the resistance 4. The voltage at the inputs of the comparators 8 and 9 is then smaller than the reference voltage of the comparator 8 but greater than the reference voltage of the comparator 9. At output X of comparator 8 there appears the logic signal 1 and at output Y of the comparator 9 the logic signal remains at zero. At the time of appearance of the positive going edge of the signal at the output X, the differentiating circuit 17 and the diode 18 produce a pulse which charges the capacitor 19. This charging of capacitor 19 switches on the motor 13 which is driven until the needle reaches its bottom position in which the light barrier 52 of the photodetector 31 is open so that the transistor of the latter is illuminated. This produces an increase of the voltage at the input of gate 21 which is connected with the photodetector and the pulse thus produced discharges the capacitor 19 through the diode 22 and the gate 21. This stops the motor.
When the pedal of the foot control is set loose and again actuated the motor is again switched on as described above while the magnet 30 is activated through the gate 29 which produces the stopping of the upper shaft 46 as described above by abutment of the stopping tappet 54 against the stopping lever 55 so that the needle is stopped in its upper stop position. The switch 26 is then closed and it discharges the capacitor 19 through the resistance 25 which switches off the motor. By repetitive backward actuations of the foot control, the needle is thus alternatively positioned in its upper and bottom positions. The flip-flop 20 prevents the discharge of the capacitor 19 by the pulse of the photodetector 31 when afterward the pedal is actuated forward. The flip-flop 20 is set when the comparator 9 produces a logic signal 1 at its output Y and it is reset when only the logic signal 1 appears at the output X of comparator 8. When the flip-flop 20 is set, any pulses from the photodetector are blocked by gate 21.
FIG. 7 shows another embodiment of the invention in which the signals from the foot control 1 are transmitted to the receiver 6 in the sewing machine as an AC voltage superimposed on the DC supply voltage. As before, the foot control preferably comprises a variable resistance 3 as well as a change over switch 2 actuated by the position of the pedal. When the resistance 3 for the regulation of the motor speed is effective, the change-over switch 2 contacts terminal A. The change-over switch 2 contacts terminal B when the pedal is turned backward. The terminals A and B as well as the resistance 3 are connected to inputs of a frequency modulator 60 the output of which is connected to the two wire cable 5 through a capacitor 61. Power is supplied through the cable 5 and a filter resistance 62 followed by a filter capacitor 63. The receiver circuit 6 comprises a demodulator 64 which receives an AC voltage from the cable 5 by means of a capacitor 65. If the change-over switch 2 is in the illustrated neutral position, the modulator 60 is ineffective; no AC voltage is transmitted and the outputs X and Y of the demodulator 64 produce logic signals of zero. When the resistance 3 is switched in, i.e., the change-over switch 2 is in position A, a range of frequencies is produced for which the demodulator 64 delivers logic signals 1 at the X and Y outputs, while it delivers at a third output a control voltage Ur for the pulse modulator 10. When the foot control is actuated backward, the change-over switch 2 assumes position B and the modulator 60 produces a frequency for which the demodulator 64 delivers the logic signals 1 and 0 at it X and Y outputs respectively. This produces, as described above, the alternate positioning of the needle from one stop position to the other stop position.
The circuit could be made somewhat simpler when no continuous changing over between the two stop positions of the needle is desired. In this case, the needle would automatically stop in its upper stop position when the machine is stopped, as described above. By means of an additional signal the ability to drive the needle from its upper stop position to another position could be provided. Alternatively, the number of comparators and the number of voltage states at their outputs can be increased in order to provide for further combinations of logic information. It would then be possible to transmit, in the simple manner described on a two-wire cable, further information corresponding to a plurality of functions to be driven, e.g., further positions of the needle, a thread cutting device or similar function. However, this would require positioning the foot control in a corresponding number of well-defined predetermined positions. | A foot control of the sewing machine can be actuated from a neutral position in two directions. In one case, a variable resistance becomes effective which produces regulating voltages within a determined range. A logic circuit with comparators produces for this voltage range a condition in which the driving motor of the sewing machine is controlled to operate with a number of turns corresponding to the voltage range. When the machine is stopped the needle is automatically positioned in its upper stop position. By repetitive actuation backward of the foot pedal the needle may be positioned in its bottom stop position and again in its upper stop position and so on. The logic treatment of the control signals from the foot control permits to transmit these signals for all required instructions through a two wire cable which is already required for the speed control. | 3 |
DEDICATORY CLAUSE
The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalties thereon.
BACKGROUND OF THE INVENTION
Known methods and apparatus for detecting missile position either touch the missile or are susceptible to false detection of X axis motion due to vibrations in the Y, Z plane. Proximity detectors, switches, and trip wires fall in the above catagory. Therefore, it can be seen that there is a need for a motion/displacement detector which functions on a fast or slow moving object by not touching the object, by detecting X axis motion despite vibration in the Y or Z axis, and by having a very small sensor that can be remotely used or mounted with its associated electronics.
Therefore, it is an object of this invention to provide a first motion detector that has no mechanical parts between the missile and launcher that may serve to give a false detection of movement of the missile.
Another object of this invention is to provide a first motion detector which detects axial motion of a missile in a launch tube.
Still another object of this invention is to provide a first motion detector which does not detect vibrations of the missile in a direction or directions that are not in the axial movement in a forward direction of the missile relative to a launch tube.
Still another object of this invention is to provide a detection device which detects the first axial motion of the missile.
Yet another object of this invention is to provide a device which is small, modest in cost, and a device which utilizes electronics that can be re-used over and over again.
A still further object of this invention is to provide a first motion detector which can be used with any missile launcher that is of the tube type, rail type, or multiples thereof.
Other objects and advantages of this invention will be obvious to those skilled in this art.
SUMMARY OF THE INVENTION
In accordance with this invention, the first motion detector includes a missile which is mounted in a conventional manner in a launch tube or relative to a launch rail and has magnetic means for producing a magnetic field that is projected outwardly from the missile into the detection range of a detector that detects when the field moves axially and thereby produces an output signal which indicates the exact time that the missile moves in an axial direction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a launch tube with a detector mounted relative thereto and with a missile inside the launch tube,
FIG. 2 is a partially cutaway and sectional view illustrating the relationship of the missile to the launch tube and the detector,
FIG. 3 is another view partially cutaway and illustrating portions in section with the missile being illustrated in a forward position in which the missile has moved linearly in relation to the detector,
FIG. 4 is a schematic electrical diagram of the detector used in this invention,
FIG. 5 is a graph illustrating the typical output characteristics of the detector of FIG. 4,
FIG. 6(a) is a plot of the missile position relative to the X axis,
FIG. 6(b) is a plot of the missile position relative to the Y axis,
FIG. 6(c) is a plot of the missile position in the X axis as it moves linearly, and
FIG. 7 is a schematic illustration of the electrical hookup of the detector to the various elements to produce the desired output.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing, in FIG. 1, a rocket 10 is mounted in a conventional manner in launch tube 12 and rocket 10 has a magnetized area 14 that produces a magnetic field 16 and detector means 18 is mounted relative to launch tube 12 in a conventional manner and within magnetic field 16 of magnetized area 14. Magnetized area 14 can either be a permanent magnetic or an electro magnet for producing magnetic field 16. In FIG. 2, prior to movement of missile 10 relative to launch tube 12, magnetic field 16 produces a flux direction as indicated by arrow 20 on detector means 18. As missile 10 moves relative to launch tube 12 as illustrated in FIG. 3, the flux direction changes as indicated by arrow 22 and this change in the action of the flux on detector means 18 causes an output to be produced as further described hereinbelow. As illustrated in FIG. 4, detector means 18 includes a magnetic wafer which is made of a material such as piezo electric material and the material changes in physical properties with the application of electrical and magnetic fields applied thereto. Magnetic wafer 24 can be a commercially available device such as a Hall-Effect Probe which is sold by Ohio Semi-Tronics; 1025 Chesapeake Ave.; Columbus, Ohio 43212 or F. W. Bell Inc., 4949 Freeway Dr. E.; Columbus, Ohio 43229.
Magnetic wafer 24 has input leads 26 connected thereto for application of a D.C. voltage I c from power supply 28 (see FIG. 7) for applying voltage to wafer 24. Leads 30 are conneted as illustrated to wafer 24 for providing a output from wafer 24. As illustrated in FIG. 4, magnetic effect from field B also acts on magnetic wafer 24 to cause the output on leads 30 to vary according to the magnitude of field B. Magnetic effect B is that produced by magnetic field 16 from magnetic means 14 as illustrated in FIGS. 1 thru 3. Referring now to FIG. 7, output leads 30 are connected to D.C. amplifier 32 that is connected to power supply 28 by leads 34 and the amplified output is delivered at leads 36 to zero crossing detector 38 that is fed power from power supply 28 by leads 40 and the output produced by zero crossing detector 38 is delivered by leads 42 to digital pulse generator 44 that receives its power input through leads 46 to produce a digital output at 48.
Magnetic wafer 24 of detector means 18 has an output D.C. voltage relative to the magnetic flux B crossing it with a signal relative to the direction (FIG. 5) of the flux. Locating detector means 18 in a forward area of a magnetically energized zone 16 produces an output D.C. voltage (for example 1 V D.C.). Sensed rocket Y or Z axis vibration (See FIG. 6 (b)) changes the signal level but not the signal (for example the signal varies from +1.0 V to 3.5 V but never less than +0). As rocket 10 moves from the position illustrated in FIG. 2 to the position illustrated in FIG. 3, the output voltage V h (FIG. 6 (a)) has a sign change and the electronics of elements 32, 38 and 44 (See FIG. 7) process these change to produce an output digital pulse at 48 which indicates the missile has moved as plotted in FIG. 6c. More specifically, the constant current I c across leads 26 of wafer 24 is forced through wafer 24 by source 28. The flux B 90° to the plane of wafer 24 creates a voltage V h across wafer 24 and between leads 30 of wafer 24. The V h voltage is proportional to the magnitude of B flux through wafer 24. A vector diagram relative to the current I c , V h , and B would show each of these 90° apart as illustrated in FIG. 4 by the various arrows.
In operation, with detector means 18 and rocket 10 positioned as illustrated in FIG. 2 and with detector means 18 in the forward portion of magnetic field 16, detector means 18 will have a D.C. output potential. After ignition of rocket 10, the rocket will move forward shifting the relative position of detector means 18 in magnetic field 16 to a position as illustrated in FIG. 3. As missile 10 is launched, magnetic means 14 moves and in turn moves magnetic field 16 relative to detector means 18 and causes output 30 to be the output from detector means 18 and to change as illustrated in FIG. 6a from a positive (negative) value through 0 to a negative (positive) value. This output from detector means 18 on leads 30 is amplified by amplifier 32 and delivered through leads 36 to zero crossing detector 38 for processing and delivery of a signal through leads 42 to digital pulse generator 44 which converts the signal to a digital output pulse 48 of the type illustrated in FIG. 6c. | An electromagnet sensing device which detects the first axial motion of a ssile relative to its launcher to provide timing information and indicate when the missile first moves axially. | 5 |
FIELD OF THE INVENTION
The present invention relates to an improved device for the production of fixed nitrogen and, more particularly, to an improved device for producing nitrogen oxides by an electric arc discharge process.
Nitrogen is an essential material in the production of fertilizers. While it is a major component of the atmosphere (79 percent in dry air), nitrogen can be incorporated into most living systems only in the "fixed" form and nitrogen is less abundant in its fixed form. Typically, chemical fertilizers contain nitrogen which is fixed by industrial methods in which nitrogen is combined with hydrogen derived from petroleum feedstocks or natural gas.
Especially in underdeveloped regions of the world, alternative processes to those dependent upon petroleum or natural gas feedstocks for producing fixed nitrogen fertilizers would help to satisfy the growing worldwide demand for fixed nitrogen fertilizers.
DESCRIPTION OF RELATED ART
Treharne et. al. (U.S. Pat. No. 4,256,967) discloses an arc reactor device for producing nitrogen oxides by an electric arc discharge process. Treharne, supra, also an inventor herein, disclosed an electrically conductive casing defining an arc discharge chamber. An electrically conductive discharge electrode was electrically insulated from the casing and extended into the chamber. An electric power source means was provided for applying an arc discharge potential between the discharge electrode and the casing, a ground electrode. A starter electrode extended into the chamber. The starter electrode was designed movable from an extended position in which it contacts the discharge electrode to a retracted position in which it is out of contact with the discharge electrode.
The Treharne reactor has been found to be an effective means of fixating nitrogen by producing nitrogen oxides from air. With the addition of water, these nitrogen oxides form dilute nitric acid solutions.
The Treharne reactor incorporated a mechanical starter electrode movable from a position of contact with the discharge electrode to a retracted position out of contact with the discharge electrode. With time the starter electrode has a tendency to corrode making arc or spark initiation by mechanical contact subject to repeated to instances of failure to initiate a spark. Often several strikes are necessary to initiate sparking. A high air flow or turbulent flow through the arc reactor can cause the arc to be blown out and extinguished. In the event the arc between the discharge electrode and casing becomes extinguished, restriking of the starter electrode by contact with the discharge electrode is necessary.
Treharne addressing the need to restrike the arc taught a solenoid actuator for moving the starter electrode. The solenoid actuator withdraws the starter electrode from the extended position to the retracted position as the arc discharge potential is applied between the discharge electrode and the casing. The d.c. power source included a first power output terminal connected to the discharge electrode, and a second power output terminal connected to the casing through a resistor. The solenoid actuator included a solenoid coil connected electrically parallel with the resistor. When the coil was energized, the actuator moved the starter electrode to its retracted position.
With age, mechanical components become increasingly unreliable in spark initiation. Also, if the solenoid actuator hesitates in arc striking, the starter electrode can stick to the discharge electrode.
A need exists for a more reliable and preferably automatic non-mechanical system of initiating and maintaining the spark in the arc reactor.
It is an object of the present invention to disclose an improved arc discharge reactor and more specifically to disclose an arc discharge reactor having an electronic starter electrode.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side cross-sectional view of an arc reactor device according to this invention.
FIG. 2 depicts a resistance capacitative oscillator type electrical circuit which switches high voltage d.c. from the discharge electrode 1 to the igniter electrode 8c and later extinguishes the igniter electrode based upon the voltage drop which occurs between the discharge electrode and casing once an arc is sustained.
SUMMARY OF THE INVENTION
An arc reactor discharge device for producing nitrogen oxides by an arc discharge process comprises an electrically conductive casing defining an arc discharge chamber, and having inlet opening means and outlet opening means communicating with said chamber. An electrically conductive discharge electrode is electrically insulated from the casing and extends into the chamber.
An igniter electrode is electrically insulated from the casing and extends into the casing proximate the discharge electrode. The igniter electrode, while of same polarity as the discharge electrode, has a smaller exposed surface area in the chamber and is positioned nearer the grounded casing than is the discharge electrode. Being of smaller surface area and closer to the casing, smaller impressed electrical potential is necessary to trigger discharge of the igniter electrode as compared to the initial potential required to cause electrical discharge or arcing via the discharge electrode.
When the igniter electrode arcs to the casing, ionization of the air molecules occurs in the immediate vicinity of the discharge electrode and casing enabling an electrical breakdown i.e. arc from the discharge electrode to the casing to be initiated at a lower potential than would be the case in non-ionized air.
It is desirable, to preserve the useful life of the igniter electrode, to provide circuitry to turn off the igniter electrode once the discharge electrode is arcing.
The present invention discloses an improved arc reactor device for fixating nitrogen of the type wherein a discharge electrode and electrical ground is provided within a chamber defined by a casing, a voltage is impressed between the discharge electrode and the ground to sustain an arc, the chamber has air inlet and outlet means for injection of air and movement of said air through said arc for the formation of nitrogen oxides, wherein the improvement comprises an igniter electrode electrically insulated from the casing extending into the chamber proximate to the discharge electrode. The igniter electrode is of smaller surface area than said discharge electrode and the igniter electrode is positioned closer to the electrical ground than the discharge electrode.
A circuit means responsive to the discharge electrode voltage is provided for switching high voltage d.c. from the discharge electrode to the igniter electrode when the discharge electrode voltage increases. The circuit means responsive to the discharge electrode voltage can be such as to cause arcing of the igniter electrode when the discharge electrode voltage increases to a set high voltage and cause arcing of the igniter electrode to cease when the discharge electrode voltage drops from the set high voltage. Preferably the circuit means responsive to the discharge electrode voltage causes arcing of the igniter electrode when the discharge electrode voltage increases to approximately 3000 volts and causes arcing of the igniter electrode to cease when the discharge electrode voltage drops to approximately 1000 volts due to arcing of the discharge electrode.
DETAILED DESCRIPTION
Reference is made to FIGS. 1-2 which illustrate the arc reactor device of the present invention. An electrically conductive casing 2 defines an arc discharge chamber 3. Chamber 3 is preferably cylindrical. Inlet opening means 6 and outlet opening means 5 are provided which communicate with chamber 3 and provide a means of supplying air to chamber 3 for the generation of nitrogen oxides and removing the air and nitrogen oxide mixture from the chamber 3, respectively.
Casing 2 is comprised of connected threaded pipe sections 2a, 2b, 2c and threaded T-pipe section 2d. FIG. 1 depicts threaded end cap 2e. Outlet opening means 5 is depicted as plug 4 having a drilled passageway orientated perpendicular to chamber 3 and optionally at some distance from end cap 2e, so as to enlarge chamber 3, create some turbulence in the air flow and increasing residence time in the reactive chamber 3. End cap 2e also functions as a convenient clean out access means.
Discharge electrode 1 is within chamber 3 held in position and insulated from the conductive casing by insulator 7. Igniter electrode 8 is positioned proximate to discharge electrode 1 preferably perpendicular thereto. Igniter electrode 8 is comprised of a metallic threaded section 8a screwed into casing 2, an insulator 8b, and an electrode 8c. The igniter electrode 8 is commonly referred to as a spark plug. As is well known in the art, a spark plug available commercially generally has a positive center electrode insulated from a negative L-shaped electrode extending from the grounded metallic threaded section. In this invention, it is advantageous if the grounded L-shaped electrode is removed from the spark plug and the spark plug's center electrode functions as the igniter electrode arcing to the grounded metallic threaded section.
A power source means, including a d.c. power source is used to apply an arc discharge potential between discharge electrode 1 and casing 2, thereby producing electrical arcing between electrode 1 and casing 2 to form nitrogen oxides from air supplied to chamber 3 through inlet opening means 6. To create air flow a pump can be used to either inject air into chamber 3 or to evacuate the air and nitrogen oxide mixture from chamber 3. Air injection is preferred at 70-100 liters per minute.
The d.c. power source means may comprise a current limit power source supplying a maximum potential of 3000 volts at no load and 1000 volts at 3 amps. The power source may be current limited such that no more than 3 amps may be supplied by the power source to the arc reactor device.
The power supply means is used to provide power to sustain the arc between discharge electrode 1 and casing 2, and is connected in parallel via a resistance capacitative oscillator or rc timing circuit to the igniter electrode. To initiate or restart the arc, the circuit via igniter electrode 8 is used.
It is desirable to preserve the useful life of the igniter electrode to provide circuitry to extinguish the igniter electrode once the discharge electrode is arcing. The present invention discloses a circuit to extinguish the igniter electrode based upon the voltage drop which occurs betwen the discharge electrode and casing once an arc is sustained. A voltage of approximately 3000 volts impressed prior to a spark between the discharge electrode and casing immediately drops to approximately 1000 volts or less when an arc occurs. With the circuitry of the present invention the igniter electrode sparks when approximately 3000 volts is impressed between the discharge electrode and casing, and the igniter electrode ceases sparking when the impressed voltage between the discharge electrode and casing drops to approximately 1000 volts.
The starter electrode, such as for example, depicted in FIG. 1 prevents sparking at the igniter electrode when an arc is present between the discharge electrode 1 and the casing 2. The circuit is basically an oscillator with its output controlling a silicon controlled rectifier that switches high voltage d.c. from the power source to the coil capacitor, typically an automobile ignition coil, leading to the igniter electrode.
The igniter electrode 8 in arcing to casing 2 ionizes the air proximate the discharge electrode 1 enabling the discharge electrode to arc through the ionized air to casing 2.
With no load, the main arc voltage (at the discharge electrode 1) is approximately 3000 volts. The circuit of FIG. 2 is a means for sensing or reacting to a voltage drop at the discharge electrode 1 when an arc is established and discontinuing the arc at the igniter electrode 8.
If the arc at the discharge electrode becomes extinguished, the main arc voltage climbs to approximately 3000 volts and the oscillator circuit of FIG. 2 causes the voltage at the igniter electrode 8 to climb to an amount sufficient to cause discharge. | An improved arc reactor device is disclosed for producing nitrogen oxides by an electric discharge process wherein the improvement is the addition of an igniter electrode and circuit responsive to the discharge electrode voltage causing arcing of the igniter electrode when the discharge electrode voltage rises to a set level. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application and claims the benefit of U.S. patent application Ser. No. 10/533,633 filed on May 2, 2005, which is entitled to the benefit of International Application No. PCT/DE2003/003642 filed Nov. 3, 2003, and German Patent Application No. 10255257.6 filed Nov. 27, 2002, and German Patent Application No. 10302406.9 filed Jan. 21, 2003, the contents of all of the foregoing applications being incorporated by reference herein in their entireties.
FIELD OF THE INVENTION
[0002] The invention relates to a card-holding device in a card-processing apparatus.
BACKGROUND OF THE INVENTION
[0003] There have come to light attempts to manipulate card-processing apparatuses of automated teller machines in which a credit card is caught by means of a catching device placed in front of the card slot of the card-processing apparatus, so that it can neither be drawn in nor conveyed back to the card slot by the conveying device of the card-processing apparatus. At a later point in time, the catching device together with the caught credit card is removed from the card-processing apparatus, whereby the credit card gets into the hands of unauthorized individuals.
[0004] Methods and devices have been proposed which comprise a technique for destroying stored information if a card is deliberately pulled out of a magnetic card reader. In the case of the proposed method, unusual stopping of a magnetic card and movement of the card after stopping are sensed and a magnetic information-destroying device is activated in dependence on the movement.
[0005] Such a method is suitable only for magnetic cards; this method cannot be used at least for erasing chip cards with contacts, since their contacts cannot come into connection with those of the card-processing apparatus if the chip card is stopped prematurely. Furthermore, after erasure, the rightful owner of the card must be issued with a new card, which leads to time delays and additional costs.
[0006] The object of the invention is therefore to propose a card-processing apparatus with a device for protecting credit cards from misuse which is suitable for all types of card.
SUMMARY OF THE INVENTION
[0007] The present invention resides in one aspect in a card processing apparatus that includes a card tray and a card transporting device for sensing the position or detention of a card in the card tray. A holding device is provided for a card. The card holding device is activated if a change in the position of the card is not detected even though a conveying signal has been issued to the card-conveying device.
[0008] The invention is based on the idea that a credit card which can be caught by means of a catching device unlawfully attached to the card-processing apparatus cannot be pulled out of the card tray if a pull-out preventer is provided. According to the invention, this is realized by a holding device which immovably secures the card even if it is attempted with great force to pull the catching device together with the card out of the card tray. However, the ability of the card to move during regular operation of the card-processing apparatus must not be hindered. A card that has stopped in an irregular manner in the card tray due to manipulation of the card-processing apparatus is detected by a change in the position of the card not being detected even though a conveying signal has been issued to the card-conveying device. In this case, the holding device is activated.
[0009] In an embodiment of the invention, the holding device has at least one gripper, which is brought into contact with one of the sides of the card when the holding device is activated. The gripper presses the card against a counter-bearing and is provided with a great holding force with respect to the card in relation to a pulling-out force. The counter-bearing may comprise a delimiting surface of the card tray or some other fixed surface located in the latter. An advantage of this embodiment is that a simple drive for the gripper can be employed.
[0010] In another embodiment of the invention, the counter-bearing is a counter-gripper located opposite the gripper and acting on a second side of the card. This embodiment has the advantage that the card is held in the middle of the card tray and is consequently not subjected to any bending forces.
[0011] The gripper and/or the counter-gripper has in the region that comes into contact with the surface of the card a high friction coefficient with respect to the card.
[0012] According to a preferred embodiment of the present invention, the gripper and/or the counter-gripper is provided in the region that comes into contact with the surface of the card with at least one tooth-like point, which is able to dig into the surface of the card. This leads to particularly reliable retention of the card, without however destroying it or making it unusable.
[0013] The gripper and/or the counter-gripper may be formed as an eccentric which is attached in a rotationally fixed manner to a shaft, which can be rotated about its axis by an electromechanical drive, and is adjustable by said shaft between a position releasing the card tray and a holding position, the shaft lying ahead of the region where the eccentric is in contact with the card.
[0014] The gripper and/or the counter-gripper is preferably formed as an arcuate arm, one end of which is attached in a rotationally fixed manner to a shaft which can be made to rotate about its axis by an electrical drive and the other, free end of which is provided with the region having the high friction coefficient or with the at least one tooth-like point, the shaft lying ahead of the contact region of the gripper and/or the counter-gripper, as seen in the drawing-in direction of the card-processing apparatus.
[0015] In another embodiment, the gripper and/or the counter-gripper is formed in the manner of a lever, and can be placed at such an angle against the surface(s) of the card that the holding force exerted on the card increases as the expended pulling-out force increases.
[0016] In another preferred embodiment of the invention, a plurality of grippers and/or counter-grippers are distributed over the width of the card tray. In this case, all the grippers and/or counter-grippers can be brought jointly into the card tray, but the depth of penetration of the individual grippers and/or counter-grippers into the card tray is independent of the other grippers and/or counter-grippers.
[0017] In still another embodiment of the present invention, the card may be secured in the card-processing apparatus by means of a bolt which penetrates the card if manipulation is attempted. The bolt is preferably fastened to a lever which is mounted transverse to the card-conveying direction and is adjustable, for example, by means of an eccentric under the power of a motor, between a first position, in which the bolt clears the card-conveying path, and a second position, in which the bolt penetrates the card and prevents conveyance of the card.
BRIEF DESCRIPTION OF THE DRAWING
[0018] An exemplary embodiment of the invention is explained below on the basis of the accompanying drawings, in which:
[0019] FIG. 1 shows a sectioned side view of the drawing-in region of a card-processing apparatus,
[0020] FIG. 2 shows the drawing-in region of the card-processing apparatus from FIG. 1 in a plan view,
[0021] FIG. 3 shows the drawing-in region of the card-processing apparatus from FIG. 1 with a credit card secured in it.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] In FIGS. 1 and 2 , the drawing-in region of a card-processing apparatus 10 is represented in a sectioned side view and in plan view. Only a flared card-insertion opening 12 and a first pair of conveying rollers 13 , the upper and lower rollers of which can be made to rotate with the aid of their conveying shafts 14 , are represented. The conveying shafts 14 and all the further card-conveying means (not represented) of the card-processing apparatus 10 are drive-connected to a card-conveying motor 15 . The conveying shafts 14 lie perpendicular to the drawing-in direction E of the card-processing apparatus 10 and parallel to a card tray 16 , which in FIG. 1 is indicated merely by its center line. A credit card 18 has been partially inserted into the card tray 16 .
[0023] The flared card-insertion opening 12 comprises an upper delimiting part 20 and a lower delimiting part 22 . A series of clearances 24 have been made in the upper delimiting part 20 and a series of clearances 26 have been made in the lower delimiting part 22 . The clearances 24 , 26 are opposite one another. The free end 28 of an arcuate gripper 30 , 32 protrudes into each of the clearances 24 , 26 to the extent that the card tray 16 still remains free. The arms 30 , 32 consist of an elastic material, for example spring steel, with a progressive elasticity curve. The upper arms 30 are connected to an upper shaft 34 and the lower arms 32 are connected to a lower shaft 36 . The free end 28 of each arm 30 , 32 is provided with a number of tooth-like points 38 . Instead of or in addition to being provided with the points, the free end 28 of the arms 30 , 32 may be provided with a material which has a high friction coefficient with respect to the material of the credit card 18 .
[0024] The upper shaft 34 is rotationally connected to an upper gear wheel 40 , which lies outside the card tray 16 and meshes with a lower gear wheel 42 mounted in a rotationally fixed manner on the lower shaft 36 . Engaging in this lower gear wheel is a pinion 44 , which can be driven by a servo-motor 46 . Instead of the gear-wheel servo-drive 40 , 42 , 44 , 46 , a lever servo-drive which can be actuated by an electromagnet may also be used.
[0025] In the region between the clearances 24 and 26 , respectively, and the pair of drive rollers 13 , an upper bore 48 has been made in the upper delimiting part 20 and a lower bore 50 has been made in the lower delimiting part 22 . The bores 48 , 50 are opposite one another and are passed through by the beam of a device for detecting the position of the credit card 52 .
[0026] FIG. 3 shows the drawing-in region of the card-processing apparatus 10 with a credit card 18 a improperly secured in the card-processing apparatus 10 by a catching device (not represented). It can be seen that the arms 30 , 32 have been adjusted into their holding position and the tooth-like points 38 are acting on the credit card 18 a.
[0027] There now follows a description of the operating principle of the card-processing apparatus 10 and the card-holding device arranged in it. In the readiness position of the card-processing apparatus 10 , the arms 30 , 32 are in their position releasing the card tray 16 , as is represented in FIG. 1 . The beam of the light barrier 52 can pass through the two bores 48 , 50 unhindered. If a credit card 18 is then pushed into the card tray 16 in the pushing-in direction E, the beam of the light barrier 52 is interrupted and its signal is transmitted to a control device 54 . This then switches on the card-conveying motor 15 , and a little later the credit card 18 is taken up by the conveying rollers 13 . The interruption of the beam of the light barrier 52 starts in the control device 54 a monitoring time within which the light barrier 52 must be cleared. This is the case if the card is conveyed properly. If, however, the credit card 18 is secured in the card tray 16 , the monitoring time expires without the light barrier 52 being cleared. The control device 54 then supplies current to the servo-motor 46 , whereupon the arms 30 , 32 are adjusted into their holding position, represented in FIG. 3 .
[0028] On account of the progressive modulus of elasticity of the arms 30 , 32 , they are capable of adapting themselves thereby on a first part of their adjusting path to different card thicknesses and also to a catching device additionally introduced into the card tray 16 . On the second part of the adjusting path, the elasticity of the arms 30 , 32 decreases to the extent that they become virtually rigid in relation to a possible pulling-out force. If it is then attempted to pull the credit card 18 a out of the card-processing apparatus 10 by force, the points 38 dig into the respective surface of the card and the arms 30 , 32 are pivoted further toward each other. As a result, the distance between the free ends 28 of the upper and lower arms 30 , 32 becomes even smaller and the retaining force of the holding device becomes even greater, so that it becomes virtually impossible to pull the credit card 18 a out of the card-processing apparatus 10 . The credit card 18 a thereby remains undamaged, apart from the impressions of the points 38 , which do not impair the function of the card. The return of the arms 30 , 32 into their release position can only be performed by authorized personnel. | In a card processing apparatus a card tray and, a card-transporting device are provided. A device for sensing the position or detention of a card in the card tray and a holding device for a card that has stopped in an irregular manner in the card tray due to manipulation of the card-processing apparatus, are also included. The holding device is activated if a change in the position of the card is not detected even though a conveying signal has been issued to the card-conveying device. | 6 |
BACKGROUND
As is known in the art, fans can be used to force air flow over circuit devices to dissipate heat. This forced air cooling is a well known thermal management mechanism used for various types of electronic equipment having circuits and circuit boards. A chassis, for example, can contain slots for an array of circuit boards, e.g., blades. A fan tray having a series of fan modules can force air into the chassis to cool the blades.
Failure of one or more of the fan modules is undesirable since air flow will be reduced. With reduced air flow into the chassis, the temperature of the components and integrated circuits on the blade may rapidly exceed specified acceptable operating temperatures and stress the components. These conditions can decrease reliability of the equipment and increase the Mean Time Between Failures (MTBF).
BRIEF DESCRIPTION OF THE DRAWINGS
The exemplary embodiments contained herein will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic representation of a fan module having sensors to measure operating characteristics;
FIG. 1A is a pictorial representation of a fan module that can be placed in a fan tray;
FIG. 2A is a perspective view of a chassis having a fan module with sensors;
FIG. 2B is a front view of a chassis having a fan module with sensors;
FIG. 2C is a pictorial representation of air flow through a chassis;
FIG. 3 is a schematic depiction of a system having a failure module.
FIG. 4 is a flow diagram showing collection of sensor data;
FIG. 5 is a flow diagram showing a leaky bucket fault prediction implementation; and
FIG. 6 is a block diagram of a system having a fault module.
DETAILED DESCRIPTION
FIG. 1 shows an exemplary fan module 100 having sensors to monitor various operating characteristics of a cooling fan 102 to detect and/or predict fan failures. As shown in FIG. 1A , the fan module 100 can be removably placed in a fan tray 101 , which can be coupled to an equipment chassis. The fan sensors can include an input temperature sensor 104 a for sensing the temperature of air flowing into the fan and an output temperature sensor 104 b for sensing the temperature of air flowing out of the fan. A current sensor 106 can monitor the current used by the fan module 100 and a voltage sensor 107 can measure a voltage supplied to the fan module. A fan blade speed monitor 108 , such as a tachometer, can monitor the speed of the fan as it rotates. A fan module temperature sensor 110 can monitor the temperature of circuitry and/or fan motor in the fan module that controls the fan. Input and output pressure sensors 112 a,b can provide a pressure differential between an input and output side of the fan. A noise sensor 114 , which can be provided as a microphone, measures ambient noise proximate the fan module 100 . A vibration sensor 116 monitors vibration levels that may indicate impending mechanical failure or anomaly.
The fan sensors collect various information to monitor the health of the cooling subsystem that may be used to predict failures. For example, fan current level and fan rotation speed baseline information can be obtained after initial operation. If the current and/or fan speed deviate from the baseline levels by greater than a predetermined amount, then an alert can be generated. For example, thresholds that are within 30% deviation can be considered non critical.
The noise sensor 114 can monitor bearing noise from the fan motor. In one embodiment, the noise information can have one or more thresholds. If the noise rises above a first threshold, a first alert for a first level can be generated, which may indicate fan maintenance is suggested. Noise above a second threshold can generate a second alert for a second level indicating that fan failure is imminent. The noise or sound sensor 114 can be placed internal or external to the fan. The signals to be captured represent both sound power or pressure and sound quality in a frequency bandwidth that may be utilized to indicate the fan or system failure modes by comparing the sound signature to existing sound signatures.
The paired pressure sensors 112 a,b measure a differential between fan intake and outtake air pressure that can form the basis of alerts when the pressure is above or below one or more threshold settings. In an alternative embodiment, pressure differential information is collected by measuring the torque to the fan blades or hub by torque sensor(s) in the blade or hub. In an exemplary embodiment, in a chassis a normal pressure differential is about 0.15″ of H 2 O. An abnormal condition due to clogged filter will increase pressure differential depending on the condition of the filter.
In one embodiment, a pressure/torque alert correlates to an abnormally reduced Free Area Ratio (FAR) resulting from, a clogged air filter, cabling blockage, insertion of an extraordinarily densely populated blade, and/or some type of obstacle placed at airflow inlet/outlet, etc. The clog or blockage can cause reduced air flow and as a result higher temperatures inside the chassis.
Power can be monitored using information from the current and voltage monitors 106 , 107 . In one embodiment, a product of electrical current I drawn by the fan and a voltage V supplied to the fan is monitored. The tachometer 108 can also provide rotation speed information.
The work performed by the fan in blowing the air corresponds to power (Watts) consumed per rotation in revolutions per minute (RPM) of the fan blade. Assume the work W=V*I/RPM. The computed work over time can be used to evaluate performance of the fan.
A gradual increase of an absolute value of W over a period of time suggests:
1) Possible Filter Clogging—if the work level goes above a predetermined threshold, it is likely that the filter should be replaced. 2) Possible Fan Mechanical failure—a gradual increase in work combined with an increase in fan motor temperature may indicate a possible fan mechanical problem 3) Possible Mechanical Failure—an increase in work in combination with certain noise and/or vibration reading may indicate an impending fan mechanical failure
A sudden increase in the amount of work performed by the fan indicates an abrupt change in the airflow condition. Possible causes of the sudden increase include:
1) Sudden obstruction to air flow in the chassis—For Example: This can be caused by installation of non compliant hardware. 2) Impending Fan Bearing Failure—, an increase in work and certain temperature, noise and vibration may point to imminent fan bearing failure. 3) Mechanical obstruction to Fan Blade rotation—This can be caused by a partial lodging of a foreign obstacle obstructing the free rotation of the fan. Noise and vibration sensor information may help identify this type of failure.
Sensor information can be combined to determine the type of failure. For example, if the fan bearing suddenly fails due to high temperature, drying up of lubricants, etc., then there would be a sudden increase in current drawn by the fan motor, a sudden drop in the speed of fan, and possibly, an increase in the noise generated by the fan and also increase in temperature of the fan motor. All these readings can be correlated to predict impending fan failure.
The tachometer 108 can be used to measure the fan spin up time, i.e., the time required for the fan to reach its operating speed. This parameter can be logged over many power-on cycles. The increase in spin up time can be used to detect fan degradation and predict fan failure. Blades in a fan are a moving part where a blade assembly rotates around a central axis of the fan. There is typically a bearing mechanism with appropriate lubricant to allow for free rotation of the blade assembly. This bearing mechanism may degrade over time and the lubricant may loose its viscosity. The fan motor may need more power and time to come up to speed.
Sensor information can be used together with diagnostic control to measure the performance of the cooling subsystem. For example, during maintenance periods and other low load periods, a fan diagnostics module can be activated and perform some online diagnostics on each fan, which can be performed sequentially on each fan. By running fan diagnostics, the over all cooling performance of the chassis is not impacted if the diagnostics take relatively little time, e.g., seconds. The diagnostics can cycle power to the fans and measure speed up time to record any changes. The recorded speedup time provides an indication of the state of lubrication and friction inside the fan mechanical components.
After receiving one or more alerts, a fan controller may increase the fan speed to maintain air flow levels. However, this may reduce the operational life of a fan module or fan tray. While the fan controller increases fan speed to compensate the air cooling loss, the fan controller can also deliver warning message or trigger alarms from its diagnostic system, correlated to the signature of each failure mode, as described below. Such a situation can be recorded as a degraded operating condition. A failure module can monitor the rate and duration of degraded operating conditions and predict failures in cooling subsystem, as described more fully below.
An exemplary list of characteristics that can be monitored includes:
Fan Spin UpTime Start/Stop Count Power On Hours Count Power Cycles Power consumed Temperature Spin High Current Spin Buzz/Noise Abnormally high Spin Speed High pressure differential caused by changed Airflow
FIGS. 2A and 2B show an exemplary chassis 200 having a fan tray 202 containing a series of fan modules 204 to force air into an interior of the chassis, which has slots 206 into which blades can be inserted. As shown in FIG. 2C the fan modules 204 can draw air into an input air plenum 208 into the chassis interior and out of the chassis via an output air plenum 210 .
FIG. 3 shows an exemplary system 300 having a failure module 302 that can monitor and/or predict failures for a processing blade 304 and a storage blade 306 , for example, based upon operating characteristics from sensors in blades and/or in a cooling system 308 , as described above. The processing blade 304 can include a processor 310 , memory 312 , and an intelligent platform management controller (IPMC) 314 . IPMC is a generic controller that performs various functions including monitoring various operating parameters, such as voltage and temperature on the various components on the platform.
The storage blade 306 can include a processor 315 , disks 316 a,b and an IPMC 318 . The blades can include a variety of integrated circuits, such as processors, programmable logic devices, etc., and discrete components, such as resistors, capacitors, transistors and diodes
The failure module 302 can include a series of agents to monitor error information that can be used to predict failures. The agents provide information to the failure module 302 for predicting failures based upon the cooling system 308 and other operating characteristics. In the illustrated embodiment, a fan failure prediction agent 320 is coupled to an IPMC 322 in the cooling system 308 . A first silicon failure prediction agent 324 is coupled to the IPMC 314 in the processor blade 304 and a second silicon failure prediction agent 326 is coupled to the IPMC 318 in the storage blade 306 . A memory failure prediction agent 328 is coupled to the processor 310 /memory 312 and a disk failure prediction agent 330 is coupled to the processor 315 in the storage blade 306 .
Integrated circuits on the blades 304 , 306 are designed to operate under specified temperature, voltage and frequency conditions. Typically these devices are validated to operate in all corners of the operating range. The operating corners could be, for example, operation at or about the upper limit of the allowed environment temperature or other parameter. Validation plans may include stressing devices beyond the normal operating ranges in various combinations of low, normal and high settings. For example, a device will be tested to operate to its full performance in a low voltage limit, a high temperature limit, and a high frequency limit of the rated specification. Based on the level of integration, function, performance, power dissipation, local heat sinks, and local fan devices of devices on the blades, hotspots on the blade may exist.
On a typical high performance blade, sensors for temperature are built into various components, such as a processor, memory module, and various chipsets. The temperature sensors are typically in the form of temperature sensing diodes connected to analog-to-digital converters providing temperature data for the silicon in these devices. Temperature sensors generally exist inside the disk drives. The IPMC controller on the blade monitors these temperature sensors and reports the data at a predetermined interval to the requesting software. In one embodiment, sensor data records are part of the IPMC internal data structures. Whenever the measured temperature crosses set thresholds, error alerts are generated by the IPMC. Voltage sensors are implemented in a similar fashion and these monitor the voltage levels on the various power supply rails on the platform.
The voltage and temperature probes should be placed as close as possible to the source of power dissipation. It may be noted that the hardware architecture of the blade in the platform can be taken into consideration and the various tolerances that can creep in due to the tolerances of functionality of each individual component. The design may be robust in specifications of performance under various extremes of voltage, frequency and temperature.
Even though a device/component/system operates with full performance, for example 100% CPU (central processing unit) load, there may be an increased likelihood that if the device/component/system continues to operate under full performance during corner conditions due to presence of other devices in the system there will be additional dynamic swings of these parameters of voltage, temperature and even frequency. These dynamic swings are likely to cause the device to operate beyond the ratings and can eventually lead to failures.
Consider a CPU rated to operate at 2 GHz with a maximum die temperature of 100 Deg C and core operating voltage of 1.9V. Due to a sudden increase in the load on the CPU, the temperature goes beyond 100 deg C, say 105 deg C, for about 30 seconds. This operation for 30 seconds at 105 deg C. is operation beyond the rated operating range. These events of dynamic swings beyond the operating range in one or more parameters at the same time will be captured as critical events of operation. The rate at which these events happen will be an indicator how over stressed the devices are, and will be used to predict the degradation of the system and can lead to eventual failures. As used herein, the term “event” refers to an operating condition when one or more of the operating parameters is beyond the rated setting.
The prediction agents 320 , 324 , 328 , 326 , 330 extract information from the sensors and based on a policy, which specifies the thresholds of lower and upper margins. The fault module 302 can monitor the sensor information to predict the likelihood of failures.
In one embodiment, the fault module 302 captures event information and builds a database 350 on each event for each event type and its occurrence frequency. The database is compact and built to contain the following information:
Sensor ID Sensor Type Sensor Policy Time Stamp Time Counter
FIG. 4 shows an exemplary process to collect sensor data. In processing block 400 , the database to store sensor information is initialized. In block 402 , threads in the prediction agents are initialized. As is well known in the art, a thread is a process that is part of a larger process or program. The prediction agent threads are then monitored, such as in round robin fashion, to collected sensor data in block 404 . In an exemplary embodiment, at a regular frequency the fault module monitors the database for new events and computes a rate of the events to determine if a stress condition has been caused due to the extreme limits of temperature, voltage and frequency and combinations thereof. Stress conditions are recorded the same or different database, which can store policy stress threshold, actual stress count/rate, timestamp, etc.
In processing decision block 406 , it is determined whether an agent reported an error condition, such as exceeding a threshold for a given parameter. If not, the prediction agent threads are monitored in block 404 . If so, in processing block 408 alert information is stored in the database for the corresponding device/platform/system, along with other information, such as timestamp.
In processing block 410 , the heuristics are compared against predetermined values to determine if the alert rate for the given parameter is greater than a predetermined value in accordance with the alert policy. The term “heuristics” as used herein refers to an application of a predetermined mechanism to determine if the rate of change is above or below the set threshold. In an exemplary embodiment, there is a policy setting for each sensor type. This could be default hard coded for certain sensor types and programmable for other.
In processing decision block 412 , it is determined whether the alert rate is above the threshold. If not, in processing block 414 the database is updated with sensor error information and threads are again monitored in block 404 . If the rate was above the threshold, in processing block 416 , an action is initiated based upon the policy set by a user. An action can include, for example, an operator alarm is triggered to notify that the system is overstressed and needs replacement.
In one embodiment, the fault module 302 utilizes a so-called leaky bucket counter for each of the above sensors, as shown in FIG. 5 . In processing block 500 , the database is initialized and in block 502 the agent threads are initialized. In processing block 504 , the leaky bucket counters are initialized for the events for which a count is maintained and monitored. In block 506 , the system waits for a stress event interrupt and the counters are decremented at predetermined time intervals. In decision block 508 , it is determined whether the event count is less than the threshold set in the policy. If so, in block 510 , an action is initiated based on the policy. If not, then in block 512 a timer is. started to count down a predetermined time interval. In decision block 514 it is determined whether the time is expired by examining the value in the timer. If the timer has not expired the timer value is re-examined in block 514 . When the timer has expired, in processing block 516 the leaky bucket counter (LBC) for a given event is incremented. In decision block 518 , it is determined whether the LBC value is greater than a predetermined value set in the policy. If so, the LBC is set to its initial value set by the policy in block 520 . If not, processing continues in block 506 . In summary, a LBC for an event decrements each time a stress event is set and at a periodic rate it is incremented. When the LBC underflows a prediction failure alarm is set. The LBC is reset to its upper limit if no stress events occur.
FIG. 6 shows an exemplary fan controller embedded system 260 having a processor 262 running instruction from a failure prediction embedded code module 264 , both of which exchange data with an error database 266 containing error and/or collected sensor information. An intelligent platform management controller (IPMC) communicates with random access memory (RAM) 270 and firmware 272 to exemplary sensors include a fan speed sensor 273 , fan motor temperature sensor 274 , fan voltage sensor 276 , fan vibration sensor 278 , and noise/sound sensor 280 . It is understood that a wide range of further sensor and sensor-types, such as temperature and voltage sensors described above, can be included.
Other embodiments are within the scope of the following claims. | Faults are monitored with information from agents for a plurality of sensors located on a plurality of circuit boards. A policy containing a error event thresholds against which the stored sensor information can be compared. Actions can be initiated by a fault module when one or more of the error event thresholds is exceeded. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application no. PCT/EP2008/002969, filed 15 Apr. 2008, which claims the convention priority of U.S. application No. 60/912,092, filed Apr. 16, 2007, and each of which is incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates to a through-substrate optical imaging device for through-imaging of translucent work objects including a radiation source outputting radiation that will be transmissive through the work object, and to an imaging system configured for capturing inspection information from the radiation source through the work object for through-imaging of translucent work objects. Further, the invention relates to a through-substrate optical imaging method for through-substrate optical imaging of translucent work objects, wherein the work object is irradiated by radiation from a radiation source and wherein inspection information from the radiation source through the work object is captured by an imaging system.
BACKGROUND OF THE INVENTION
Through-substrate optical imaging devices include a radiation source outputting radiation that will be transmissive through the work object. Furthermore, the known devices include an imaging system configured for capturing inspection information from the radiation source through the work object.
There is a need for improved imaging systems, particularly inspection systems in the manufacturing of semiconductor devices to determine whether or not certain structures are present. Typically, the structures are defects. While the inventive subject matter may be used in various imaging or inspection applications, it will be illustrated herein in the context of a Micro Electro Mechanical System (MEMS) inspection.
The general structure of a Micro Electro Mechanical System (MEMS) device involves a device wafer, electronic or mechanical components located on the device wafer, a barrier surrounding the edge of the device wafer, and a cap wafer. During the assembly of the MEMS device, a frit is affixed to the bottom of the cap wafer. The cap wafer is then pressed down onto the device wafer causing the frit to create a bond with the device wafer.
In one method of determining if the device has seal integrity, a beam of infra-red (IR) or near infra-red (NIR) light is projected either through the top (toplight or Si Reflect Method) or the bottom (backlight, transmissive or Si-Thru method) of the wafer. On the top side of the wafer is a camera or photodetection device.
The standard method to detect seal defects is to project infrared or near infrared collimated light orthogonally to the device surface on one side to check for seal integrity. When the wafer is illuminated with infrared or near infrared collimated light, the seal extents and gross voids in the seal are easily detected.
Unfortunately, in this method illumination of the device wafer does not highlight subtle delamination between the seal and the device wafer to which the seal is bonded. This failure to highlight the subtle defects results because delaminations do not significantly affect transmission of the light passing through the device wafer and the frit. Accordingly, there is a need for improved inspection systems in MEMS inspections and other inspection applications.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the invention to overcome the drawbacks of the prior art.
It is another object of the present invention to provide an improved through-substrate optical imaging device and method.
The inventive subject matter addresses the foregoing need by providing improved imaging devices for use in through imaging of translucent objects. Usually these translucent through-objects are semiconductor devices and similar work objects. In certain respects, the inventive subject matter is directed to a device and method for creating a substantially non-collimated light source that will allow a determination of whether or not certain structures are present in an object under inspection. In one possible application, the device and method are directed to detection of subtle delaminations between a device wafer and the frit.
The invention is based on the idea to irradiate the work object with a beam such that the angle of incidence of the light ray varies from the normal. If e.g. a light source is used as a radiation source, a plurality of light rays is directed onto the surface of the work object such that at least some of the light rays impinge on the surface in a non-perpendicular manner. It has been found that in this way the optical imaging is improved substantially, in particular with respect to image quality and detection of fine structures, in particular subtle delaminations. Consequently, the inventive device allows for optical imaging with a high image quality and therefore for the detection of features, either intended features or defects, in particular of delamination in a wafer structure.
According to a preferred further embodiment of the invention beam forming means or device are provided for forming the beam of a radiation source such that the radiation impinges on the surface of the work object under various angles of incidence. According to the respective application, the beam forming means or device may be chosen within wide ranges.
In order to provide a relatively simple and cost-effective beam forming means, according to a further preferred embodiment the beam forming means includes at least one optical diffuser which is located between the radiation source and the work object, such that the diffused radiation impinges on the surface of the work object. The diffuser has the effect that a collimated or near-collimated beam, for example a light beam, is diffused so that the angle of incidence of the light rays varies from the normal and the light rays or at least some of the light rays impinge onto the surface of the work object under various angles.
According to an alternate embodiment, the radiation source or a radiation source point of the radiation source is angularly positionable relative to the work object, such that in different angular positions of the radiation source or the radiation source point of the radiation source the radiation impinges on the surface of the work object under different angles of incidence. In this embodiment a collimated or near-collimated light source may be used without a diffuser. Various angles of incidence are obtained in this embodiment by angularly positioning the radiation source or the radiation source point relative to the work object. In this way, the same effect is obtained as in the embodiment using the diffuser. Within the terms of the invention the radiation source point is defined as a point of the radiation source from which the radiation leaves the radiation source or a radiation guide means or device, for example an optical fiber means or optical fiber device. Consequently, the radiation source and the radiation source point may be spaced apart from each other.
According to a further development, in particular of the beforementioned embodiment, the radiation source or the radiation source point of the radiation source is positionable in a plane (X-Y plane) substantially parallel to the surface of the work object, such that various locations of the work object may be irradiated in various positions and/or orientations of the radiation source or the radiation source point relative to the work object. In this embodiment, during an inspection of the work object the radiation source or the radiation source point scans the surface of the work object continuously or in a step-wise manner in order to have the work object inspected at various locations.
Basically, any suitable radiation source may be used. According to a further preferred embodiment the radiation source is a light source. In particular, for inspection of semiconductor devices, light in the infrared or near-infrared (NIR) range may be used.
According to a further preferred embodiment the light-source is a semiconductor-based light-source. Suitable semiconductor-based light-sources are widely available and relatively cost effective.
According to a further preferred embodiment at least two radiation sources or radiation source points are provided which are configured for preferably simultaneously irradiating the work object from at least two locations. In this embodiment detection of subtle structures is further improved. If e.g. a work object is inspected using two or more light sources, it may occur that an edge of an internal structure of the work object is parallel to the light rays from one light source and therefore is difficult to detect. By using at least the second light source irradiating the work object under a different angle, detection of corresponding edges or similar structures is simplified.
An inventive through-substrate optical imaging method for through-imaging of a translucent work has likewise been achieved.
According to an embodiment of the inventive method for through-substrate optical imaging of translucent work objects, the work object is irradiated by radiation from a radiation source, and inspection information from the radiation source through the work object is captured by an imaging system. In that manner the work object is irradiated by radiation which impinges on the surface of the work objects under various angles of incidence and/or orientations.
According to another embodiment of the inventive method the beam of the radiation source is formed by beam forming means, such that the radiation impinges on the surface of the work object under various angles of incidence.
According to a further embodiment of the inventive method a diffuser is used which is located between the radiation source and the work object, such that the diffused radiation impinges on the surface of the work object.
According to another embodiment of the inventive method the radiation source or a radiation source point of the radiation source is angularly positioned relative to the work object, such that in different angular positions of the radiation source or the radiation source point the radiation impinges on the surface of the work object under different angles of incidence.
According to a yet further embodiment of the inventive method the radiation source or a radiation source point of the radiation source is positioned in a plane (X-Y plane) substantially parallel to the surface of the work object, such that various locations of the work object may be irradiated in various positions and/or orientations of the radiation source or the radiation source point relative to the work object.
According to another embodiment of the inventive method a light source is used as a radiation source.
According to a still further embodiment of the inventive method a semiconductor-based light-source is used as a light source.
According to another embodiment of the inventive method at least two radiation sources or radiation source points are used which are configured for preferably simultaneously irradiating the work object from at least two locations.
In certain embodiments, the inventive subject matter is directed to using collimated light, an optical system for diffusing the light, and an image processing system for detecting subtle delaminations between the device wafer and the frit.
Alternate embodiments include the use of a collimated light source, but, adjusting the light with beam forming methods so that the angle of incidence of the light rays varies from the normal. This adjustment eliminates the need for an optical system diffuser.
The foregoing is not intended to be an exhaustive list of embodiments and features of the present inventive concept. Persons of ordinary skill in the art are capable of appreciating other embodiments and features from the following detailed description in conjunction with the drawings.
The invention will now be explained in greater detail with reference to the accompanying drawings wherein all features described, illustrated in the drawings or claimed in the claims constitute the subject matter of the invention, either taken alone or in arbitrary combination with each other, regardless of their combination in the claims and the references of the claims as well as regardless of their description in the specification and their illustration in the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1A shows a PRIOR ART assembly that is used to detect gross voids using collimated light;
FIG. 1B is one possible embodiment of an inventive device that is used to detect subtle delaminations in a work object using non-collimated light created by an optical assembly;
FIG. 2A shows a detailed view of the work object prior to assembly;
FIG. 2B shows a detailed view of the work object after assembly where there is a proper bond between the frit and the device wafer;
FIG. 2C shows a detailed view of the work object after assembly where there is an improper bond between the frit and the device wafer caused by subtle delamination on the edges;
FIG. 2D shows another detailed view of the work object after assembly where there is an improper bond between the frit and the device wafer caused by subtle delamination internally;
FIG. 3A shows a detailed view of the ray pattern of collimated light passing through the device wafer, the frit, and the cap wafer;
FIG. 3B shows a detailed view of the ray pattern of the non-collimated light passing through the device wafer, the frit, and the cap wafer;
FIG. 4 shows an exemplary image of the delamination image patterns created by the passing of non-collimated light through the device wafer, the frit, and the cap wafer, and these delamination image patterns displayed after detection from an image processing system;
FIG. 5A shows a diagram of a low angle halogen light source illuminating a wafer without a metal layer in the wafer;
FIG. 5B shows a diagram of a low angle light source illuminating a wafer with a metal layer in the wafer; and
FIG. 6 shows a diagram of a low angle semiconductor light matrix illuminating a wafer with a metal layer in the wafer.
DETAILED DESCRIPTION OF THE INVENTION
As indicated above, the present invention is illustrated in the context of an inspection of a Micro Electro Mechanical Device (MEMS), but is not intended to be limited to this inspection application.
FIG. 1A depicts a PRIOR ART collimated light source 20 , a work object 30 interposed between the light source 20 , a photodetector 40 , and an imaging system 50 . Exemplary wavelengths of the light source 20 are in the infrared or near infrared range. The work object 30 consists of a device wafer 32 , a frit 34 , and a cap wafer 36 . The work object 30 , can be any device with one or more layers that are translucent to the light emitted from the light source 20 . The photodetector 40 is connected to the imaging system 50 , which may consist of an image processing system 52 , and a display 54 , or a printer 56 . Gross voids or seal extents are only detected when the collimated or near-collimated light 32 passes through the device wafer 32 , the frit 34 , and the cap wafer 36 . The modified non-collimated light 24 creates an image on the photodetector 40 . The output from the photodetector 40 is processed by the imaging system.
FIG. 1B depicts one possible embodiment of an inventive system that includes a collimated light source 120 , an optical system 160 , a work object 130 , a photodetector 140 , and an imaging system 150 . The wavelengths of the collimated light source 120 are in the infrared or near infrared range. The collimated light source 120 projects collimated rays 122 through an optical assembly 160 . The optical assembly 160 receives a light beam from the collimated light source that is slightly smaller than the area being detected by the imaging system 150 . The optical assembly 160 modifies the collimated beam to create a formed beam 124 . This diffused beam 124 rays strike the device wafer at angles that are other than normal. The beam 124 then travels through the device wafer 132 , the frit 134 , and the cap wafer 136 . The exiting diffused beams 126 are detected by the photodetector 140 suitable photodetector including, for example, a CMOS or CCD image sensor. The output from the photodetector 140 is connected to the imaging system 150 . The imaging system 150 includes an image processor 152 . The system may further include a display 154 and/or a printer 156 . The photodetector 140 and imaging system 150 may not be limited to a CMOS sensor, but may also employ other photodetection means or device, such as photomultiplier tubes, or cryogenic particle detectors.
FIGS. 2A , 2 B, 2 C, and 2 D, show a side view of the system. FIG. 2A shows a side view of the work object prior to the bonding, the work object consisting of the cap wafer 210 , the printed frit 220 , and the device 230 . In FIG. 2B , an exemplary view of a good bond is shown. The printed frit 220 is compressed on the device wafer 230 without any voids or delaminations. In FIG. 2C a poor quality bond (e.g., bad bond) is shown with delaminations 240 in the area between the printed frit and the device wafer. In FIG. 2D a poor quality bond is shown with a void 250 between the device wafer and the printed frit.
FIGS. 3A and 3B depict ray tracing through the device wafer, the printed frit, and the cap wafer. In FIG. 3A , a view of collimated rays 340 is shown projected through the device wafer 330 , the printed frit 320 , and the cap wafer 310 . A collimated ray strikes an area of subtle delamination 350 at a normal angle, but is not deflected. The ray then continues through the printed frit 320 , exiting the cap wafer in a normal fashion 310 . This is the ray path of the PRIOR ART assembly, as shown in FIG. 1A .
In FIG. 3B , non-collimated rays 360 strike the device wafer 330 . The rays then strike the area of subtle delamination 350 and are deflected according to Snells law (e.g. n 1 sin θ 1 =n 2 sin θ 2 ). The non-collimated rays 360 can trace two different paths. The first path is through the device wafer 330 , the printed frit 320 , and the cap wafer 310 . The second path is through the device wafer 330 , the area of subtle delamination 350 , the printed frit 320 , and the cap wafer 310 . The exit angle of the first path and the second path differ by refractive index of the area of subtle delamination 350 . It is this difference in the exit angle that is captured by the photodetector and displayed by the image processing system. It is also possible for the exit angle to be affected by texture differences due to delamination as a result of bad seal bonding.
In FIG. 4 , the photodetector and image processing system displays the areas of non-collimated light 410 that are indicative of subtle delamination. The size and intensity of these areas are dependent on the size and structure of the areas of subtle delamination. The method of determining if there is a defect is typically done by comparing a known or reference image with the actual image. With the use of CCD capture technology and image processing systems, comparing a reference image to the actual image may be done using software.
Now referring back to FIG. 1B , exemplary solid-state light sources, systems and applications in which the inventive subject matter contemplated herein may be used include those set forth in U.S. National Phase patent application Ser. No. 10/984,589, filed May 8, 2003, entitled “High Efficiency Solid-State Light Source and Methods of Use and Manufacture,” published as US2005/0152146A1 on Jul. 14, 2005, which is incorporated herein by reference in its entirety for all its teachings. U.S. National Phase patent application Ser. No. 10/984,589 discloses, among other things, high-intensity light sources that are formed by a micro array of semiconductor-based light sources, such as LEDs, laser diodes, or VCSEL placed densely on a substrate to achieve power density output of at least 50 mW/cm 2 (i.e., 50 mW/cm squared).
Exemplary solid-state light sources, systems and applications in which the inventive subject matter contemplated herein may be used include those disclosed by U.S. Nonprovisional patent application Ser. No. 11/109,903, filed Apr. 19, 2005, entitled “Imaging Semiconductor Structures Using Solid State Illumination,” published as US2005/0231713A1 on Oct. 20, 2005, which is incorporated herein by reference. U.S. Non-provisional patent application Ser. No. 109,903 discloses, among other things a solid state light source that irradiates selected semiconductor-based structures via a fiber optic light guide and a lens system. The source's radiation is directed to structures via an internal beam splitter in the lens system. The radiation, so directed, generally is reflected by structures at various intensities (e.g., depending on the bond characteristics and other features and defects of the semiconductor structures), so as to travel back up through the lens system, to a camera, such camera being based on or using one or more solid state imaging devices, e.g., CCD or CMOS detectors. The camera preferably detects such reflected radiation of one or more wavelengths. Via such detection, an image of the structures is captured. The image, so captured, may be provided for further processing via, e.g., computer The captured image, so processed or otherwise, may be employed for test and quality control, toward identifying relevant features of such structures e.g., where such relevant features are associated with bonded or stacked layers (e.g., in the interfacing layer(s) of bonded or stacked substrates or in the bond itself) or with other bonded or stacked materials.
U.S. Provisional Patent Application No. 60/888,874, filed Feb. 8, 2007 entitled “Semiconductor Light Sources, Systems, and Methods” is incorporated herein by reference.
Optical diffusers necessary to create the non-collimated beam from the collimated beam examples of which being: a holographic diffuser or an optical glass diffuser.
An alternate embodiment of the inventive subject matter involves the adjustment of the collimated or near-collimated light source. For example, the collimated or near-collimated light source is rotated off axis such as to have the beam strike the device wafer at an angle other than normal to the wafer surface. The beam refracts through the wafer in the same fashion as a diffuse ray passing through the surface off the normal axis. This eliminates the need for an optical system to diffuse the light. Implementations of this embodiment may include a mechanical adjustment of the light source or the adjustment of the mount holding the wafer.
Referring to FIG. 5A , an exemplary implementation of the alternate embodiment for use with silicon wafers that do not have metal layers is shown. This implementation consists of a collimated light source 510 , fiber bundle 520 , and the light source point 540 , with the light source point 540 positioned at an angle 530 to the underside of the wafer 560 . An imaging system 550 captures and processes the image in a manner previously described. An implementation of the light source 510 consists, for example, of a halogen light (model MHF-D-100-CR manufactured by Moritex, www.moritex.co.jp) with a silicon filter to pass near infrared light. The light source 510 is typically 5 mm in diameter, but may be of a greater or lesser diameter. The coherent light from the light source point 540 illuminates the wafer at an angle 530 from 5 to 25 degrees relative to the surface of the wafer 560 . The light source point 540 is located approximately 100 mm from the center of the wafer 560 . The light source point 540 is positioned at various points 540 ′, 540 ″, and 540 ′″ and at various angles 530 ′, 530 ″, 530 ′″ to observe the areas of delamination with the camera 550 . Alternately a fiber ring (not shown) with uniform illumination that is located approximately 20-50 mm. from the surface of the wafer 560 may be utilized.
Referring to FIG. 5B , the implementation of the alternate embodiment for use with silicon wafers that have metal layers is shown. This implementation consists of a collimated light source 510 , fiber bundle 520 , and the light source point 540 , with the light source point 540 positioned at an angle 530 to the top side of the wafer 570 . An imaging system 550 captures and processes the image in a manner previously described. An implementation of the light source 510 a halogen light (model MHF-D-100-CR manufactured by Moritex, www.moritex.co.jp) with a silicon filter to pass near infrared light. The light source 510 is typically 5 mm in diameter, but may be of a greater or lesser diameter. The coherent light from the light source point 540 illuminates the wafer at an angle 530 from 5 to 25 degrees relative to the surface of the wafer 560 . The light source point 540 is located approximately 100 mm from the center of the wafer 560 . Alternately a fiber ring (not shown) with uniform illumination that is located approximately 20-50 mm from the surface of the wafer 560 may be utilized.
Now referring to FIG. 6 a semiconductor light matrix 600 (manufactured by Phoseon Technology Inc., Beaverton, Oreg., www.phoseon.com) is shown illuminating the wafer 630 . The output of the semiconductor light matrix 600 is coupled to focusing lens 610 . The semiconductor light matrix 600 and focusing lens 610 combination is positioned at an angle 620 from the wafer 630 surface. The camera 640 takes images of wafer 630 surface to detect areas of subtle delamination. The semiconductor light matrix 600 is positioned at various points 600 ′, 600 ″ and at various angles 620 ′, 620 ″ such that the entire wafer may be inspected. The use of a semiconductor light matrix 600 can also be configured to illuminate the top of the wafer 630 for metal layer wafers or illuminate the bottom of the wafer 630 in the same manner as depicted in FIGS. 5A and 5B .
While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, and uses and/or adaptations of the invention and following in general the principle of the invention and including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains, and as may be applied to the central features hereinbefore set forth, and fall within the scope of the invention. | A through-substrate optical imaging device for through-imaging of translucent work objects, includes a radiation source outputting radiation that will be transmissive through the work object and an imaging system configured for capturing inspection information from the radiation source through the work object. The radiation source is configured such that the radiation impinges on the surface of the work object under various angles of incidence. A method for through-substrate optical imaging of a translucent work object includes irradiating the translucent work object by radiation from a radiation source; capturing inspection information from the radiation source through the translucent work object, the inspection information being captured by an imaging system; and irradiating the translucent work object. The translucent work object is irradiated by radiation which impinges on the surface of the translucent work object under one of various angles of incidence and orientations. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to molds and more particularly to a mold for use in forming snow blocks.
[0003] 2. General Background
[0004] It is common for children and adults in those parts of the world having heavy snowfall or beaches to form structures from the snow or wet sand. Oftentimes such structures are formed from blocks or other shapes that have been formed by compressing the snow or wet sand into a container such that the compressed material takes on the shape of the interior of the container. Numerous examples of such molding systems exist, such as shown, for example in U.S. Pat. No. 3,685,942 where the molding member is formed as a scoop, or U.S. Pat. No. 2,752,631 where the molding member is formed as part of a snow shovel or U.S. Pat. No. 3,713,431, where the molding member is formed of a four-sided housing and an L-shaped scoop and compressor, which interfits with the housing to form the block or the five-sided mold of U.S. Pat. D246,664. Many means of extraction of a formed block have been proposed, such as the ejector shown in U.S. Pat. No. 3,859,029 or the strap shown in U.S. Pat. No. 3,848,846.
[0005] While such molding systems assist in providing shaped snow blocks, and address, in differing designs, one or more of approaches to a snow molding form, however each design has deficiencies associated therewith, which are overcome with the present invention.
SUMMARY OF THE INVENTION
[0006] The present invention provides a forming mold for molding snow or wet sand into a block shape conforming to the interior dimensions of the mold. The mold is provided with sidewalls having an initial upward and outward taper to facilitate funneling of snow into the mold body, a secondary taper to facilitate release of the packed material from the mold body, a down-turned exterior skirt spaced from the sidewall of the mold extending downwardly from adjacent the top of the sidewalls, which can provide a gripping surface for lifting the mold but which also functions as a protected attachment point for a bail with the free ends of the bail residing between the sidewall and the downwardly extending outer flange. The sidewalls terminate at their end opposite the open top end in an in-turned flange, which provides support for a removable bottom. A bead or a series of beads is formed on the interior of the sidewalls spaced from an upper surface of the in-turned flange by a dimension approximately equal to the thickness of the removable bottom, whereby the bottom can be snapped into place between the bead and the flange. The bottom is provided with openings therethrough allowing for drainage of water during the snow compaction process. If desired, a secondary cover may be provided to fit within the flared section of the upper portion of the sidewalls to assist in compacting the snow into the mold, however such an additional top piece is supplemental since children using the mold can easily push the snow into shape with their hands.
[0007] It is therefore an object of this invention to overcome deficiencies in prior art snow molds and to provide a simple, easily constructed, inexpensive snow mold.
[0008] In an embodiment of the invention the snow mold comprises a four-sided mold member having an in-turned flange at the bottom of the sidewalls, a removable bottom member received against the in-turned flange and held in place thereagainst by interference fit projections on an interior surface of at least some of the sidewalls spaced from the in-turned flange.
[0009] In a further embodiment of the invention, the mold consists of a four-sided main mold member defined by sidewalls having tops and bottoms, the sidewalls at the top being flared outwardly with respect to remaining portions of the sidewalls and terminating in a downwardly extending skirt spaced from the sidewall, the mold being provided with a removable bottom conforming to the interior dimensions of the sidewalls adjacent a bottom thereof.
[0010] In an embodiment of the invention, a mold body is provided having a plurality of sidewalls forming an enclosure, the sidewalls having bottom forming in-turned flanges leaving the majority of the bottom of the enclosure open, a removable bottom plate is insertable into the body against the in-turned flanges, releasable projection means are formed on the inside surfaces of at least some of the sidewalls effective to hold the bottom in above against the flange but to allow the bottom to snap out of position to be removed through the top of the mold body thereby pushing the contents of the mold from the enclosure, the bottom being provided with drainage openings therethrough.
[0011] It is therefore a general object of this invention to provide an improved snow mold for use in molding snow into blocks or other shaped three-dimensional solid or semi-solid forms and to provide for easy removability of the formed shape from the mold. This and other objects will be apparent to those of ordinary skill in the art from the description of the preferred embodiment and giving reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a perspective view of the mold according to this invention showing the bottom positioned outside of the mold body.
[0013] FIG. 2 is an enlarged cross-section view generally along the lines ii-ii of FIG. 1 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] As shown in FIG. 10 , the apparatus of this invention consists of a mold 10 formed generally as a four-sided surround 11 having end sides 12 and 13 and long sides 14 and 15 , the mold being shown as rectangular. The sides join at rounded edges 16 . It will be understood that the mold could be square or formed from shaped side walls into other shapes and could, for example, be formed on an arc or curvature to form different types of blocks of snow or other compatible material.
[0015] FIG. 2 is an enlarged partial cross-section taken generally along the lines ii-ii of FIG. 1 and illustrates sidewall 14 which is tapered slightly outwardly from an inside corner bottom 18 upwardly to a intermediate point 20 spaced from a top 21 of the wall 14 . The wall portion between the intermediate point 20 and the top 21 tapers outwardly at a greater angle than the taper between the bottom corner 18 and the intermediate point 20 so as to form essentially a funneling surface for funneling snow into the main body section 30 of the mold. An inwardly projecting bead 32 is positioned above an in-turned bottom flange 33 by a distance approximately equal to the thickness of a mold plate bottom 40 . The mold bottom plate 40 is removable from the mold by snapping it upwardly past the bead and distorting the bottom 40 enough to snap around the bead. The material of the bottom plate 40 is of a plastic having a resiliency sufficient to allow it to snap into position between the bead 32 and the in-turned flange 33 and to snap out of it under pressure pushing it towards the open top 50 .
[0016] The bead may, as shown in FIG. 1 , be substantially continuous extending entirely around the periphery of the mold body 14 or, as shown in FIG. 2 , may be intermittent, reducing the amount of force necessary to remove the bottom from the position between the bead and the in-turned bottom flange 33 . The bead creates an interference fit with the undistorted shape of the bottom plate 42 .
[0017] An outer skirt 51 extends downwardly from the top 21 in spaced relation to the walls 12 - 15 forming an opening 52 . Preferably the skirt 51 extends substantially parallel to the lower section of the walls, which, as mentioned above, are slightly outwardly tapered. The skirt can be straight or slightly outwardly tapered itself. The skirt forms a gripping area so that a person, perhaps equipped with mittens or gloves, can grab the mold from around its periphery. Preferably the entire mold is formed of a sufficiently resilient plastic that a child's finger would not get stuck in the space 52 . The skirt also allows for a wider top which is preferably not sharp edged.
[0018] The skirt 51 can also serve as the attachment point for a bail 60 formed of a generally U-shaped wire member 61 , which has hook ends 62 extending through openings 63 in the skirt and being bent into the space 52 so as to resist removal. Although I've shown the mold as utilizing one bail, it can be understood that the mold may have two bails, one closer to the wall 12 and wall closer to the wall 13 , the bails being long enough the be brought together over the center of the mold to aid in lifting. The bottom 40 is provided with openings 44 therein, which will allow drainage as the snow is compacted into the mold body 14 .
[0019] In the preferred embodiment, as shown the openings 44 may be formed as finger holes to allow the bottom to be maneuvered both to snap it into position and to pull it out of position when the mold is empty. Generally, in use of the mold, snow or wet sand or other formable material will be molded into the mold body 14 , with the aid of the funnel shape of the top portion of the walls, and with the bottom in place. A second bottom shaped member may also be provided to aid in compacting the material into the mold to approximately the height of the intermediate section 20 of the sidewalls thereby forming generally a rectangular block as shown in the mold embodiment illustrated. The bottom can then be pushed upwardly or, upon inversion of the mold, downwardly, to break loose the compacted formed block by snapping the bottom 40 beyond the bead 32 . The tapered wall portions will aid in release of the formed block.
[0020] If desired, the inside of the walls may be formed with vertical ribbing or the like to add detail to the formed block or the top and/or bottom surface of the bottom may be provided with a three dimensional feature or indicia, such as the words “snow mold” as illustrated to impress into the molded block, a feature, including advertising, which will then form part of the top of the block as the mold is inverted and the block is pushed out.
[0021] From the above it will be appreciated that this invention provide an improved block-forming mold for use in compacting snow, wet sand or the like into individual blocks, the mold consisting of an at least four-sided open top and open bottom enclosure with a snap-in, snap-out bottom, which in the snap-in position rests between a raised section on an interior wall and an in-turned flange at the bottom of the peripheral walls. A funnel-shaped top section of the peripheral walls aids in compressing quantities of loose snow or the like into the actual mold forming intermediate section where tapered walls assist in extraction of the molded block on inversion of the mold form. A peripheral downwardly extending skirt provides a gripping feature and a place for affixing the ends of a bail or bails without being projecting into the interior mold.
[0022] Although I have shown this invention in connection with a preferred embodiment, those skilled in the art will understand that it may be practiced in many different designs, variations and manufactured of many different materials and in different shapes. | A five-sided open top forming mold for material such as snow having peripheral walls with in-turned flanges at a bottom thereof, a mold bottom adapted to rest against the in-turned flanges, inter-engaging edge portions of the bottom and configurations on the walls retaining the bottom in place until application of a force sufficient to overcome the retention whereby the bottom can push the molded material out of the mold, and the bottom can be re-snapped into position at the bottom before another material molding. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a hemming apparatus and method for forming a hem on an edge of a sheet metal member and, more particularly, the invention relates to the forming of a hem on an edge of a structural sheet member such as an automobile body panel or similar multipart structure.
2. Description of the Prior Art
Sheet metal folding or hemming is a technique that has gained widespread use in many industries including the automotive industry. Hemming is utilized to form a piece of metal that serves as a reinforcing element for external automobile components such as doors and hoods. For example, the trunk lid for most automobiles is of two-piece construction in which the outer edge of the exterior element of the trunk lid is folded over against the outer edge of an inner reinforcing element by a hemming process.
The hemming procedures, as described in the prior art, utilize an outer element with the outer edge prefolded in the form of a flange to lie nearly perpendicular to the main portion of the outer element. Such preforming is most conveniently done in the stamping operation, that is, customarily utilized in the forming of such outer element. The hemming of such flange requires that it be folded over from such prefolded condition at approximately a right angle to be against the outer edge of the inner element after the inner element has been placed inside the upturned flange of the outer element. The folding over or hemming of the flange of the outer element in many hemming processes of the prior art is accomplished in multiple stages, usually in two stages. In a first stage, force was applied generally perpendicular to the original orientation of the flange to cause it to bend a considerable angle from its original orientation in which a second stage force was applied generally parallel to the original orientation of the flange to cause the partially bent flange to bend an additional amount to complete the folding of the flange from its prefolded condition to securely engage the outer edge of the inner element of the two piece structure that was being hemmed. Such two stage hemming process is done in separate sets of tools and the required tooling for such an operation is rather massive, costly, and space consuming. Additionally, a two stage hemming process requires a transfer operation to transfer the workpiece that is being hemmed from the first stage tooling to the second stage tooling. Such a transfer operation, which is generally synchronized, involves special transfer equipment and poses additional risks of equipment malfunction which can lead to interruptions on the production line. Multiple stage hemming operations of the aforesaid type also require for process consideration a certain minimum depth of flange in the outer edge flange of the outer element that exceeds the depth of the flange that would otherwise be required based on the product requirements of the component that is being hemmed. Then, too, the finished component is more costly and has a greater weight than would otherwise be necessary.
The present invention differs from the hemming tool that is shown and described in U.S. Pat. No. 4,706,489 entitled "Single Station Hemming Tool" issued Nov. 17, 1987 to Ernest A. Dacey, Jr. The hemming tool set forth in the above referenced patent utilizes a plurality of similar hemming tools that are spaced strategically around the perimeter of an automobile panel component. Each one of the hemming tools is similar in construction and is activated by a common actuator. The hemming tool has a flange contacting member and through a system of cams and levers the flange contacting tooling is initially driven generally perpendicular of the flange with respect to the original orientation of the flange of the outer element to accomplish a first stage hemming or prehemming of such flange and is subsequently driven generally parallel to the original orientation of the flange to complete the hemming or folding of the flange. As the hemming tool approached the flange of the component to be hemmed, the tool traveled along a first elliptical path, then a second elliptical path was utilized to complete the hemming operation. The mechanism for driving the hemming tool through a path with two elliptically arcuate portions included a cam that moved the center of movement of the hemming tooling from the center of the first ellipse to the center of the second ellipse at a predetermined point in the movement of the hemming tool that corresponds to the completion of the first elliptically arcuate movement. In order to accomplish the aforesaid compound elliptical movement, there was a heavy reliance upon a complicated cam and cam follower arrangement that was difficult to keep in adjustment and also was prone to unacceptable wear. The present invention does not use the cam system taught in the above referenced patent. Also, the present invention provides a greater freedom of movement of the tooling than what is described in U.S. Pat. No. 4,706,489.
The advantages of performing an entire hemming operation in a single stage is recognized in U.S. Pat. No. 3,276,409 entitled "Assembly Machine" issued Oct. 4, 1966, to Edouard R. St. Denis. This patent shows a hemming structure that employs several like units spaced around the periphery of a panel component that is to be hemmed. A pair of fluid driven cylinders is employed to drive the hemming tool of each unit toward the upstanding portion of an outer panel flange that is to be crimped or hemmed. The tooling first contacts the upstanding panel flange near the free end of the flange. The flange is then bent to nearly half of its final bend. The tooling then slides over and downward upon the already bent flange in order to hem the outer panel into tight engagement with the inner panel. At no time did the tooling leave contact with the outer panel flange, thus, undesirable stretching of the panel material was a distinct possibility. In the present invention, the tooling performs an initial bend then reorients itself remote from the flange before performing the final hemming step.
A somewhat similar hemming machine is shown and described in U.S. Pat. No. 3,191,414 entitled "Hemming Machine or Fixture" issued June 29, 1965, to James A. Kollar et al. The Kollar et al machine utilizes two fluid driven cylinders to move the hemming steel in a direction toward the anvil. The workpiece is placed on the anvil with the outer panel of the workpiece already bent to approximately a right angle. Through the action of one fluid driven cylinder, the hemming steel moves generally parallel to the surface of the anvil thus causing an additional bending of the upstanding flange to an acute angle configuration. The second fluid driven cylinder then causes the hemming steel to move toward the anvil surface thus completing the hemming operation. At no time does the hemming steel leave contact with the flange of the workpiece. The continuous contact of the tooling with the workpiece can in some instances produce undesirable stretch marks in the workpiece. The present invention is an improvement over the just cited art in that the hemming steel is completely reoriented after it makes initial contact with the workpiece.
In U.S. Pat. No. 4,484,467 entitled "Beaded Edge Forming Method and Apparatus" issued Nov. 27, 1984, to Mikio Kitano et al, there is set forth a method of hemming the flange of a workpiece. The method involves essentially two deforming steps. First, a deforming tool is moved vertically downward toward an upstanding workpiece flange, the downward tool movement deforms the flange until it is partially bent, and the deforming tool is then moved out of contact with the workpiece flange. Second, a hemming tool is moved into position above the partially bent flange of the workpiece, the hemming tool is lowered vertically against the workpiece flange thus crimping it into final position, and the hemming tool contacts only the outer portion of the workpiece flange thus preserving a previously formed bead at the base of the workpiece flange. The present invention employs a method that causes the hemming tool to disengage itself from contact with the workpiece, however, only one hemming tool is used whereas the method set forth in U.S. Pat. No. 4,484,467 requires two separate tools in order to perform the hemming method.
SUMMARY OF THE INVENTION
The invention sets forth a method of and an apparatus for hemming an outer peripheral flange of an outer sheet metal element of a multiple element panel assembly to overlie the outer edge of an inner element of such panel assembly. The flange of the outer sheet metal is moved from an original position that is generally perpendicular with respect to the inner portion of the assembly. The entire hemming operation is performed at a single station without the need for the transfer of the assembly to another work station. The hemming apparatus has an anvil and a juxtaposed hemming steel that act in conjunction with one another to effect the hemming operation through a system of shafts and lever arms.
The invention includes a support structure of upright configuration that is mounted on a support plate that is oriented in a generally horizontal attitude. The support structure supports an anvil through a pair of cantilevered arms. It also supports a hemmer bracket that can swing arcuately into and out of engagement with the anvil. The hemming steel is attached to the hemmer bracket and its movement is controlled by moving the hemmer bracket bidirectionally under the influence of a lower eccentrically mounted shaft that is coupled to a crank arm. The top portion of the hemmer bracket is moved toward and away from the anvil by the linking together of a plurality of crank arms coupled between the support structure and the hemmer bracket. The crank arms are operated by a linear motion device well known in the art. Because of the manner in which the hemming steel of the present invention contacts the flange of the outer element of the workpiece, the final positioning of the flange can be controlled in a manner heretofore not possible by a single station hemming apparatus. The complete hemming of a flange at a single work station helps to reduce the cost and in some instances the weight of the assembly that is being fabricated.
The movement of the hemming steel of the present invention, in the case of hemming generally horizontally positioned metallic components, the outer component or element having a flange to be folded over by the hemming tool from a generally vertically extending original position to a generally horizontal final position, involves a sequence of arcuate motions which, respectively, approximate horizontal and vertical motions. The first of such motions follows an arcuate path which brings the hemming steel into contact with the upstanding flange of the outer element. The outer element is thus partially bent over to form an acute angle of approximately 45 degrees. The hemming steel then backs off from contact with the partially bent outer element and then advances to a position more directly over the flange of the outer element. The advancement of the hemming steel to its new position over and adjacent to the partially bent flange of the outer element is achieved through an arcuate movement of the hemming steel. Once the hemming steel has reached its position above and remote from the flange of the outer element, the hemming steel then moves arcuately toward the flange, makes contact, and continues such arcuate travel until the outer flange has achieved its final crimped position. Through a series of arcuate movements, the hemming steel is moved upward and outboard of the hemmed component, enabling it to be removed from the apparatus.
Thus, it is an object of the present invention to provide an improved method and apparatus for assembling an inner element to an outer element by hemming at a single station.
A primary object of the present invention is to provide a hemming apparatus that can perform multiple hemming steps with the same hemming steel at the same work station.
Another object of the present invention is to provide an apparatus that is compact and can be actuated with other like and adjacently positioned units by a common power source.
A further object of the present invention is to provide an apparatus that can perform a metal hemming operation with a minimum of drag and marring of the workpiece.
An additional object of the present invention is to power the hemming apparatus through a plurality of linearly applied reversible forces.
Another object of the present invention is to provide an apparatus in which the hemming steel is supported by a bracket that can undergo arcuate movement in more than one direction.
A further object of the present invention is to provide a method for the hemming of a metallic flange in which the hemming steel is moved into and out of contact with the metallic flange a plurality of times.
Still another object of the present invention is to provide an apparatus that permits a variation in the sequence in which the hemming steel is manipulated in the vicinity of the workpiece.
Other objects and advantages of this invention will be more apparent after a reading of the following detailed description taken in conjunction with the drawings provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view that shows one of several like units that can be placed adjacent to one another and supplied with power from a common source;
FIG. 2 is an elevational side view of the invention that shows part of the support structure for the anvil and the hemming steel;
FIG. 3 is an elevational end view of the apparatus as shown in FIGS. 1 and 2;
FIG. 4 is a plan view of the apparatus which shows the anvil and part of its support structure along with the hemming steel and the hemming bracket;
FIG. 5 is a cross-sectional view taken along lines 5--5 of FIG. 2 which shows the lower crank arm and the eccentrically journaled shaft to which it is attached;
FIG. 6 is a cross-sectional view taken along lines 6--6 of FIG. 2 which shows the upper crank arm and the linkage between the support frame and the hemmer bracket;
FIG. 7 is a fragmentary cross-sectional view taken along lines 7--7 of FIG. 3 that shows the interaction between the guide shoes and their respective wear plates;
FIG. 8 is a schematic side view of the lower crank arm when rotated to its uppermost position;
FIG. 9 is a view similar to FIG. 8 except that the lower crank arm is in its lowermost position;
FIG. 10 is a schematic outline of the upper crank arm when rotated to its uppermost position;
FIG. 11 is a view similar to FIG. 10 wherein the upper crank arm is in an intermediate rotated position;
FIG. 12 is an additional view similar to FIG. 10 wherein the upper crank arm is rotated to its lowermost position; and
FIG. 13 is an enlarged schematic view of the circle 13--13 of FIG. 2 which shows the workpiece and the path of travel of the hemming steel.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and more particularly to FIG. 1, there is illustrated in perspective an overall apparatus 16 for the hemming of, for example, the door of an automobile. The overall apparatus 16 is but one of a series of similar hemming devices that surround a panel that is to be hemmed. All of the similar hemming devices can be operated simultaneously from a common power source as is well known in the prior art. The overall apparatus 16 is used to perform a process of sheet metal bending that is generally described as a hemming process to join a pair of sheet metal parts. The outer part is generally that portion of the workpiece that subsequently supports a painted surface. Consequently, the surface of the outer part must be as free as possible from tooling marks. The outer part is generally prepared for the hemming operation by creating around its peripheral edge an upstanding flange that is approximately perpendicular to the panel portion of the outer part. This configuration of the outer part permits the inner part to be nested within the confinement of the upturned flange of the outer part.
The overall apparatus 16 requires a substantial support such as a series of base pads 18. Each one of the base pads 18 has an upstanding support column 20 affixed thereto. A rigid base plate 22 spans the distance between the upstanding support columns 20. The base plate 22 is preferably welded to the tops of the support columns 20, however, bolts could also be utilized. A columnar bracket 24 is attached to a top surface 26 of the base plate 22 by a series of spaced apart bolts 28. The columnar bracket 24 is of welded construction that is stress relieved and machined to the final required dimensional tolerances. A pair of spaced apart side plates 30 and 32 support the vertical loads attributable to the remainder of the upper structure of the overall apparatus 16. The side plates 30 and 32 are stabilized by a rear plate 34 and a lower front plate 36 that contains an aperture 38 therethrough. A top front plate 40 spans the distance between the side plates 30 and 32. An anvil support plate 42 is horizontally disposed and attached to the top of the side plates 30 and 32 as well as the upper edge of the top front plate 40. An anvil 44 is attached to the anvil support plate 42 by a series of heavy duty bolts (not shown). The anvil 44 is quite massive so that it will hold its contoured top surface without deforming under repetitive loading during the operation of the overall apparatus 16. In addition to the anvil 44, the columnar bracket 24 has attached thereto a cantilevered bracket 46. The cantilevered bracket 46 is attached to the top front plate 40 by a series of bolts 48. The cantilevered bracket 46 is also of welded construction with a pair of vertical side plates 50 and 52 arranged in spaced apart parallel orientation. The cantilevered bracket 46 has a back plate 53 which abuts the top front plate 40. The bolts 48 pass through the back plate 53 and are tapped into the top front plate 40 of the columnar bracket 24. The cantilevered bracket 46 has a horizontally positioned intermediate plate 54 and a top plate 56. The cantilevered bracket 46 also has a pair of upwardly extending arms 58 and 60 which provide support for several components of the present invention which will be discussed hereinbelow.
As can be viewed in FIG. 1, the overall apparatus 16 is rather narrow in width so that another like unit can be placed adjacent thereto. The overall apparatus 16 and like units are powered by a ring like structure that circumscribes all of the units. Segments of two such ring structures 62 and 64 are shown in FIG. 1. The ring structure 62 moves along a vertical path designated by the numeral 66. Likewise, the ring structure 64 moves along a vertical path 68. The ring structures 62 and 64 can be actuated by any well known power source such as fluid driven cylinders (not shown).
FIG. 2 is an elevational side view of the present invention that depicts a portion of the columnar bracket 24 with the anvil 44 mounted thereon. Also shown is a side view of the cantilevered bracket 46 which is attached to the columnar bracket 24. A hemmer bracket 70 is supported by the cantilevered bracket 46. The hemmer bracket 70 is similar to a box in configuration. Two vertically oriented elongate plates 72 and 74 are arranged in spaced apart parallel orientation. The elongate plates 72 and 74 are coupled together at the bottom by a cross bar 76 which is attached preferably by welding. The top section of the hemmer bracket 70 is immobilized by an L-shaped cross member 78 which is also welded firmly to the elongate plates 72 and 74. A pair of spacers 80 and 82 are positioned against the reentrant surfaces of the L-shaped cross member 78. An additional cross plate 84 is positioned adjacent to the L-shaped cross member 78 and tied into the elongate plates 72 and 74. The hemmer bracket 70 is held in position on the overall assembly 16 by essentially four support points. The two lower support points are provided by the ends of an eccentric shaft 86 which is journaled in the walls of the elongate plates 72 and 74. The two upper support points are provided by support shafts 88 and 90. As will be described in more detail below, the hemmer bracket 70 can be moved to a limited extent in all except lateral directions. In particular, the hemmer bracket 70 is heavily reinforced at its top end by the L-shaped cross member 78 and the cross plate 84 to help resist the deflection that occurs when the hemming steel 92 is biased against the anvil 44. The hemmer bracket 70 straddles the cantilevered bracket 46 with the elongate plates 72 and 74 lying outboard of the upwardly extending arms 58 and 60.
FIG. 3 is an elevational end view of the overall apparatus 16 as shown in FIGS. 1 and 2. The elongate plates 72 and 74 of the hemmer bracket 70 are shown as they extend from the cross bar 76 of the bottom of FIG. 3 to the cross plate 84 at the top. The upwardly extending arms 58 and 60 of the cantilevered bracket 46 are shown positioned inboard of the elongate plates 72 and 74. The hemming steel 92 not only spans the distance between the elongate plates 72 and 74, but, also, extends beyond them in a horizontal direction. The lower portion of the hemmer bracket 70 is supported by the horizontally aligned eccentric shaft 86 that has an enlarged central span 94. Each end of the enlarged central span 94 of the eccentric shaft 86 is journaled in the cantilevered bracket 46 with a set of bearings 96 and 98. The ends 100 and 102 of the eccentric shaft 86 are of reduced diameter and have a common axis that is offset from the axis of the central span 94. A lower crank arm 104 is clamped at the midpoint of the enlarged central span 94 of the eccentric shaft 86. The lower crank arm 104 has a diametrical split at its enlarged end that permits clamping to the eccentric shaft 86. The clamping of the lower crank arm 104 is facilitated by a keeper 106 and a pair of clamp bolts 108. The keeper 106 and the bolts 108 can best be seen in FIG. 2. The cantilevered end of the lower crank arm 104 contains a bore 110 through which a shouldered bolt 112 is installed. A spherical male rod end 114 is held in position by the bolt 112. The male rod end 114 is attached to a push-pull rod 116. The shouldered bolt 112 is retained in the bore 110 by a nut 118.
A crank arm assembly 120 is mounted in a horizontal attitude between the upwardly extending arms 58 and 60 of the cantilevered bracket 46. The crank arm assembly 120 has a central shaft 122 of enlarged diameter. The central shaft 122 is rotatably mounted in the upwardly extending arms 58 and 60 of the cantilevered bracket 46 by a journaling system more fully explained later herein. The crank arm assembly 120 has a cantilevered upper crank arm 124 that is attached to the central shaft 122. The upper crank arm 124 is positioned centrally along the central shaft 122 and is attached thereto preferably by welding. The end of the upper crank arm 124 has a bore 126 through the free end. A shouldered bolt 128 is positioned through the bore 126 and is immobilized by a nut 130. The shouldered portion of the bolt 128 captivates a spherical male rod end 132 which in turn is attached to the end of a push-pull rod 134.
FIG. 4 is a plan view of the overall apparatus 16 which shows the top of the anvil 44 and part of its support structure along with the hemming steel 92, the cantilevered bracket 46, and the hemmer bracket 70. The contour of the surface of the anvil 44 and the companion hemming steel 92 is not of linear configuration as can be seen in FIG. 4. The width of the overall apparatus 16 is defined by the anvil 44 and the hemming steel 92, therefore, a similar apparatus can be placed adjacent thereto to operate in unison under the influence of a common power source.
FIG. 5 is a cross-sectioned view taken along lines 5--5 of FIG. 2 which shows the lower crank arm 104 and the eccentrically aligned journaled eccentric shaft 86 to which it is attached. The top front plate 40 of the columnar bracket 24 is shown at the left side of FIG. 5. The back plate 53 of the cantilevered bracket 46 is attached to the top front plate 40 by the bolts 48, as shown in FIG. 1. The vertical side plates 50 and 52 of the cantilevered bracket 46 are preferably attached to the back plate 53 by welding. A bore 136 is positioned in the elongate plate 72. An eccentric cartridge 138 is positioned in the bore 136. The eccentric cartridge 138 includes a bore 140 into which the reduced diameter end 100 of the eccentric shaft 86 is journaled by a bearing 142. In a similar manner, the other end 102 of the eccentric shaft 86 is journaled in a bearing 144 that is retained in a bore 146 within an eccentric cartridge 148, which in turn is positioned in a bore 150 in the elongate plate 74. Thus, the lower end of the hemmer bracket 70 can move with respect to the immobile cantilevered bracket 46. The central span 94 of the eccentric shaft 86 has a greater diametrical extent than does the reduced diameter ends 100 and 102. The ends of the central span 94 are journaled within the bearings 96 and 98. The bearing 96 is positioned in a bore 152 in the vertical side plate 50; likewise, the bearing 98 is positioned in a bore 154 in the vertical side plate 52. Returning once again to the lower crank arm 104, which is positioned at the center of the eccentric shaft 86, a pair of keys 156 and 158 are utilized to prevent rotational movement of the lower crank arm 104 with respect to the eccentric shaft 86. The key 156 is positioned in a groove 160 within the eccentric shaft 86 and a complementary groove in the keeper 106. The key 158 is positioned in a groove 162 within the eccentric shaft 86 diametrically opposite the key 156. The key 156 is held in a complementary groove within the lower crank arm 104. The keys 156 and 158 are held in position when the bolts 108 (see FIG. 2) are installed in the keeper 106 and the lower crank arm 104.
In order to provide lateral stylization and adjustment, a washer 164 is positioned on one side of the lower crank arm 104 adjacent to the central span of the eccentric shaft 86.
Another washer 168 is positioned in juxtaposed relationship on the other side of the lower crank arm 104. The washers 164 and 168 are anchored by a pair of bolts 166 and 170, respectively. In conjunction with the washer 164, a retainer 172 is positioned between the washer 164 and the inner surface of the vertical side plate 50. The retainer 172 is longitudinally in alignment with the axis of the eccentric shaft 86. An additional retainer 174 is positioned between the inner surface of the vertical side plate 52 and the washer 168. The retainers 172 and 174 are held in position with bolts 176 and 178.
FIG. 6 is a cross-sectional view taken along lines 6--6 of FIG. 2 which shows the upper crank arm 124 and the linkage between the cantilevered bracket 46 and the hemmer bracket 70. The top front plate 40 of the columnar bracket 24 is shown at the left of FIG. 6. The back plate 53 of the cantilevered bracket 46 is shown adjacent to the top front plate 40. The top plate 56 is also shown as it spans the distance between the base of the upwardly extending arms 58 and 60. The crank arm assembly 120 of which the upper crank arm 124 is a component is shown as it is mounted between the upwardly extending arms 58 and 60. The crank arm assembly 120 has a block 180 which is in opposed relationship with respect to the upper crank arm 124. The block 180 and the upper crank arm 124 are preferably attached to the central shaft 122 by welding. The crank arm assembly 120 is supported by a pair of bolts 184 and 186 which are journaled in a pair of bearings 188 and 190. The bearing 188 is positioned in a bore 192 in the upwardly extending arm 58 and the bearing 190 is similarly positioned in a bore 194 in the upwardly extending arm 60. The bolts 184 and 186 pass through respective transverse bores 196 and 197 in the ends of the central shaft 122. A reduced diameter threaded section on the ends of the bolts 184 and 186 retains them in the crank arm assembly 120. The block 180 of the crank arm assembly 120 contains a transverse bore 195 that is parallel to the axis of the central shaft 122.
A drag link 198 is supported by the support shafts 88 and 90. The outer end of the support shaft 88 is journaled within a bushing 202 that is positioned within a bore 204 in the elongate plate 72. The drag link 198 has a shaft end 206 that contains a bore 208 in which a pair of spaced apart bearings 210 and 212 are separated with a spacer tube 214. The pair of spaced apart bearings 210 and 212 contain an elongate apertured bushing 216. The support shaft 88 is partially contained within the apertured bushing 218 that is positioned within a bore 220 in the elongate plate 74. The drag link 198 has a shaft end 222 opposite the shaft end 206. The shaft end 222 contains a bore 224 that contains a pair of spaced apart bearings 226 and 228 that are separated by a spacer tube 230. An elongate apertured bushing 232 is positioned within the bearings 226 and 228. The support shaft 90 is journaled within the apertured bushing 232 and in the bushing 218 that is contained in the elongate plate 74.
The drag link 198 contains a pair of integrally fixed legs 234 and 236. The leg 234 contains a bore 238 into which a bearing 240 is inserted. Likewise, the leg 236 contains a bore 242 for a bearing 244. A removable pin 246 is trained through the transverse bore 195 in the block 180 and also through the bearings 240 and 244. The removable pin 246 is maintained in position by cotter pins (not shown). An aperture 248 is placed in the elongate plate 72 and a similar aperture 250 is placed in the elongate plate 74. The apertures 248 and 250 facilitate rapid disassembly of the removable pin 246. The upper crank arm 124 which is an integral part of the crank arm assembly 120 contains a reduced thickness section 251 at the end thereof in the vicinity of the bore 126.
FIG. 7 is a fragmentary cross-sectional view taken along lines 7--7 of FIG. 3 that shows the interaction between a pair of guide shoes 252 and 254 and their respective wear plates 256 and 258. The guide shoe 252 is contained within a bore 260 that is located near the midsection of the elongate plate 72. The guide shoe 252 is held in position by bolts 262 which pass through a flanged area 264 on the guide shoe 252 and into threaded engagement with the elongate plate 72. The wear plate 256, which is preferably made of bronze, is attached to the upwardly extending arm 58 of the cantilevered bracket 46 by recessed bolts 266. The guide shoe 254 is positioned within a bore 268 that is positioned through the elongate plate 74. The guide shoe 254 is captivated by a series of bolts 270 that pass through a flanged area 271 of the guide shoe 254 and into the elongate plate 74. The wear plate 258 is similar in material and configuration to the wear plate 256 and is held in place by a plurality of recessed bolts 272. The leading edges of the wear plates 256 and 258 are beveled to facilitate the movement of the guide shoes 252 and 254 thereover. The guide shoes 252 and 254 control the lateral movement of the hemmer bracket 70 as it moves under the influence of the lower and upper crank arms 104 and 124.
FIG. 8 is a schematic side view of the lower crank arm 104 when it is rotated to its uppermost position. When in the position shown in FIG. 8, the lower crank arm 104 is inclined at an angle of approximately thirty degrees with respect to the horizontal. The lower crank arm 104 has a center of rotation that is coincident with the longitudinal axis of the central span 94 of the eccentric shaft 86 which rotates but does not undergo a translation (see FIG. 5). Thus, the center of rotation of the lower crank arm 104 is represented by the numeral 274. The center of the axis that passes through the reduced diameter ends 100 and 102 is identified by the numeral 276. As the lower crank arm 104 rotates about the fixed center of rotation 274, the center 276 of the reduced diameter end 100 moves in an arcuate path. Since the reduced diameter ends 100 and 102 are journaled in the hemmer bracket 70, the lower portion of the hemmer bracket 70 also moves in an arcuate path. The net effect of such arcuate movement causes the entire hemmer bracket 70 to be lifted primarily in a vertical direction with a minimum of horizontal displacement.
FIG. 9 is a schematic side view similar to FIG. 8 except that the lower crank arm 104 is in its lowermost position. The lower crank arm 104 is shown in a position that is approximately thirty degrees below the horizontal. In this position, the center 276 has moved arcuately down from its previous uppermost position. With the center 276 in its lowermost position, the entire hemmer bracket 70 is lowered. Thus, the up and down motion of the hemmer bracket 70 can be very accurately controlled. Since the lower crank arm 104 has a push-pull rod 116 (see FIGS. 1 through 3) that is independent of all other controls, the hemmer bracket 70 can be raised or lowered at any time during the hemming cycle.
FIG. 10 is a schematic outline of the upper crank arm 124 when it is rotated to its uppermost position. When the upper crank arm 124 is in the position shown in FIG. 10, it makes an angle approximately thirty degrees with respect to a horizontal plane. Since the upper crank arm 124 and the block 180 are both attached to the crank arm assembly 120, the block 180 and the removable pin 246 have rotated to a lowermost position. The lower position of the removable pin 246 causes the legs 234 and 236 of the drag link 198 to assume a position of greatest angle with respect to the horizontal. Consequently, the drag link 198 has moved to the right. The drag link 198 moves to the right when the upper crank arm 124 is in an up position because the drag link 198 is journaled in the hemmer bracket 70 which rotates about the center 276 (see FIG. 2).
Also shown in FIG. 10 is an adjustment and set up stop mechanism. A cantilevered tab 278 is rigidly attached to a central section of the drag link 198. An adjustment screw 280 is positioned within a threaded bore in the cantilevered tab 278. A similar cantilevered tab 282 is rigidly attached to the end of the block 180. The attitude of the crank arm assembly 120 and the drag link 198, as viewed in FIG. 10, causes the cantilevered tabs 278 and 282 to be a considerable distance from one another.
FIG. 11 is a view similar to that shown in FIG. 10 wherein the upper crank arm 124 has rotated to an intermediate position. In the attitude shown in FIG. 11, the upper crank arm 124 has assumed a rotational position that is approximately ten degrees below the horizontal plane. Of course, the entire crank arm assembly rotates, consequently, the block 180 has rotated to a more horizontal position. As the block 180 rotates toward a horizontal attitude, the removable pin 246 moves toward the left, causing the drag link 198 to also move toward the left. The movement of the drag link 198 to the left causes the hemmer bracket 70 to rotate counterclockwise about the center 276 (see FIG. 2). The cantilevered tabs 278 and 282 have approached each other but have not made contact with each other as can be seen in FIG. 11.
FIG. 12 is an additional view similar to FIG. 10 wherein the upper crank arm 124 has assumed its lowermost position. The upper crank arm 124 has assumed a position that is approximately thirty degrees below the horizontal plane. The clockwise rotation of the crank arm assembly 120 has caused the block 180 to assume an axial position slightly above the horizontal plane. In this position, the block 180 has carried the removable pin 246 to its left most position. The drag link 198 also moves to the left, causing additional counterclockwise rotation of the hemmer bracket 70 about the center 276. In the position shown in FIG. 12, the cantilevered tabs 278 and 282 have moved toward each other until the adjustment screw 280 has made contact with the top surface of the cantilevered tab 282. The adjustment screw 280 permits small angular adjustments to be made during initial set up of the overall apparatus 16 and the adjustment of the push-pull rod 134.
ASSEMBLY AND OPERATION
The assembly of the overall apparatus 16 of the present invention is uncomplicated because of the simplicity of the design. The base plate 22 and the support column 20 along with the base pad 18 can be welded together if desired. The columnar bracket 24 is then bolted to the base plate 22 with the bolts 28 and the cantilevered bracket 46 is then bolted to the columnar bracket 24 with the bolts 48. The eccentric shaft 86 and accompanying bearings 96 and 98 are installed in the cantilevered bracket 46. The lower crank arm 104 and its adjustment mechanism is installed on the eccentric shaft 86. The wear plates 256 and 258 are attached to the outer surfaces of the cantilevered bracket 46 with the recessed bolts 266 and 272. The hemmer bracket 70 is coupled to the reduced diameter ends 100 and 102 by installation of the eccentric cartridges 138 and 148 after the guide shoes 252 and 254 have been installed. The drag link 198 is equipped with its multiple sets of internal bearings 210 and 212, 226 and 228 suspended across the hemmer bracket 70 by the support shafts 88 and 90 and accompanying bushings 202, 216, 218 and 232. The crank arm assembly 120 is then installed with the aid of the bearings 188 and 190 and the bolts 184 and 186. The anvil 44 is then installed to the anvil support plate 42 with bolts (not shown). The hemming steel 92 is anchored to the L-shaped cross member 78 by bolts (not shown). The spacers 80 and 82 are sized and installed with the hemming steel 92. The removable pin 246 is installed, thus coupling the drag link 198 to the crank arm assembly 120. The push-pull rods 116 and 134 and their associated hardware are adjusted to the proper length and coupled to the upper and lower crank arms 124 and 104.
FIG. 13 is an enlarged schematic view of the circle 13--13 of FIG. 2 which shows a workpiece 284 and the path of travel of the hemming steel 92. At the initial start position, the hemming steel 92 is at a location remote from the anvil 44. The start point is designated by the numeral 286 which is shown at the right side of FIG. 13. The initial start position is also the load position when the workpiece 284 is positioned on the anvil 44 of the overall apparatus 16 and adjacently positioned similar hemming apparatus. In order for the hemming steel 92 to assume the load position, that is, the point 286, the upper crank arm 124 is at the top of its rotation which will be designated as up sixty degrees. This position is depicted in FIG. 10. At the load or start position, the lower crank arm 104 is at the up sixty degrees position, as shown in FIG. 8. The upper and lower crank arms 124 and 104 begin a slow clockwise rotation under the influence of their respective push-pull rods 134 and 116. The upper crank arm 124 stops at a down forty degrees position whereas the lower crank arm 104 rotates to a down sixty degrees or bottom location. At this time the hemming steel 92 has moved to a point 288 just to the left of the edge of the workpiece 284. During the travel of the hemming steel 92 from the point 286 to the point 288, the outstanding flange 290 of the workpiece 284 is moved to the location 292. The upper crank arm 124 is then moved up forty degrees and simultaneously the lower crank arm 104 is moved up sixty degrees. Thus, the hemming steel 92 returns to the point 286. The upper crank arm 124 then moves to a down sixty degrees position thus moving the hemming steel 92 to the point 294. The lower crank arm 104 is then moved to the sixty degrees down position thus moving the outstanding flange 290 to the location 296. At this time, the hemming steel 92 is at the point 298. The lower crank arm 104 is then moved to the up sixty degrees position causing the hemming steel 92 to leave the point 298 and return to the point 294. The upper crank arm 124 is then moved to the up sixty degrees position, causing the hemming steel 92 to return to the point 286 which is the initial loading point.
Since the upper and lower crank arms 124 and 104 are independent of one another, their movement can be programmed to vary the movement of the hemming steel 92 according to the demands of the particular workpiece.
The present invention also encompasses a method of hemming a multipart workpiece wherein a portion of the workpiece 284 is folded over upon itself as depicted in FIG. 13. In the prior art methods of hemming, the initial bend is made by a downward motion of the hemming steel. The downward motion of the hemming steel is then followed by a sliding forward motion with the hemming steel, in essence, ironing the bent outstanding flange 290 to its final position. In the present invention, the hemming steel 92 makes contact with the outstanding flange 290 of the workpiece 284 and bends it to a partially closed position. The hemming steel 92 is then moved away from the partially closed outstanding flange 290 to the point 286. The hemming steel 92 then moves forward over the partially closed outstanding flange 290 without actually making contact therewith. The hemming steel then moves from the point 294 toward the workpiece 284, causing the outstanding flange 290 to be folded against the remainder of the workpiece 284. The hemming steel 92 arrives at the point 298 when the outstanding flange 290 is completely folded. The hemming steel 92 is not dragged across the surface of the workpiece 284 as it is removed. Instead, the hemming steel 92 is lifted to a position where it no longer contacts the workpiece 284 before the hemming steel 92 is moved to a location remote from the workpiece 284. Of course, it is evident to those skilled in the art that the exact sequential horizontal and vertical movement of the hemming steel 92 can be varied.
While the illustrative emboidment of the invention has been described in considerable detail for the purpose of setting forth practical operative structures whereby the invention may be practiced, it is to be understood that the particular apparatus described is intended to be illustrative only, and that the various novel characteristics of the invention may be incorporated in other structural forms and method steps without departing from the spirit and scope of the invention defined in the appended claims. | An apparatus and method for forming a hem on an edge of a sheet metal member including an anvil attached to a columnar support structure that also includes a cantilevered bracket that is the support for a movable hemmer bracket to which a hemming steel is attached. By the utilization of a pair of crank arms, the hemmer bracket is movable through a plurality of arcuate paths which permits the hemming steel to perform multiple forming operations on a workpiece held by the anvil. The method includes the steps of partially hemming a sheet metal member, then disengaging the hemming steel contact with the workpiece, then moving the hemming steel to a new location before recontacting the workpiece with the hemming steel. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a sewing machine electronically storing the stitch control data which are sequentially read out to produce various patterns of stitches. More particularly the objective of the invention is to control the basic or reference needle position of a member of patterns which are produced sequentially in combination by such a type of sewing machine.
In a zigzag sewing machine which may produce various patterns, it is generally required to produce the stitch patterns with a predetermined basic (or reference) needle position which may be located at the right end, left end or the middle of the maximum swinging range of the needle most properly for the patterns. In case the sewing machine operator wishes to produce a number of patterns sequentially in combination especially with adjustment of the needle swinging amplitude, it is undesirable that the needle swinging amplitude be adjusted on both sides of the basic needle positions which may be different in dependence upon the different patterns. Namely, it is undesirable to shift the basic needle positions each in dependence upon the different patterns. It is therefore a primary object of the invention to memorize a combination of different patterns with designation of a basic (or reference) needle position common to these patterns.
According to the conventional sewing machine producing stitch patterns including straight stitches, the straight stitches are produced with a basic needle position generally set at the center (or middle) M of the maximum swinging range of the needle. It is actually desirable for many stitch patterns including zigzag stitches to set the basic needle position at the center M of the maximum needle swinging range. This requirement, however, different with respect to a pattern such as a pattern of a tulip as shown in FIGS. 1(A) and 1(B). As to the patterns such as the tulip, it is preferable to set the basic needle position at the left end L of the maximum needle swinging range, because such a pattern is easily positioned with the basic needle position L with respect to the fabric to be sewn, and because the pattern may be varied in size from minimum to maximum with reference to the basic needle position L. As to the pattern of blind stitches, it is preferable to set the basic needle position at the left end L of the maximum needle swinging range, because such stitches are produced with reference to the edge of the fabric to be sewn. No problem arises if the different stitch patterns of different basic needle positions are produced separately and individually. A problem arises if these patterns are produced sequentially in combination. Namely, the difference of basic needle positions prevents the combination of patterns from being produced in alignment with each other. Actually if the combined patterns of different basic needle positions are produced in the maximum size in the maximun needle swinging range, these patterns are produced in alignment with each other and no problem arises as shown in FIG. 1(A). On the other hand, if the size of these combined patterns are adjusted (or reduced), these patterns are so reduced with reference to the difference basic needle positions each specific to the patterns, and as the result, the sequential patterns are produced to and fro out of alignment.
SUMMARY OF THE INVENTION
An object of the present invention is to solve such a problem of the prior art. In keeping with this object and other which will become apparent hereafter, the invention substantially comprises; a first memory storing stitch control data for different stitch patterns to be selectively produced, pattern selecting means including a number of pattern selecting switches which are selectively operated to produce a pattern signal designating the corresponding are of the patterns stored in the first memory, pattern memory control means operated to determine a combination of different patterns, a second memory operated in response to the operation of the pattern selecting means and of the pattern memory control means to memorize the combination of different patterns in a predetermined sequence, needle swing adjusting means operated to adjust the swinging amplitude of the needle with a common variation rate with respect to each of the stitch control data read out from the first memory in response to the designation of the patttern signals memorized in the second memory, a third memory storing basic needle position designating signals each specific to the patterns stored in the first memory, basic needle position control means operated in response to the operation of the pattern memory control means to memorize a specific one of the basic needle position designating signals to control the stitches of the designated combined patterns with a common basic needle position, calculating means operated in response to the output signal of the basic needle control means, the stitch control signal of the first memory and the output signal of the needle swing adjusting means to adjust the swinging amplitude of the needle with a common variation rate with respect to each of the stitches of the combined patterns, and to set a common basic needle position for the patterns, and stitch forming means operated in response to the output of the calculating means to produce the stitches of the combined patterns. According to another feature of the invention, separate and individual patterns are produced with the basic needle positions each specific to the patterns.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1(A) and 1(B) show by way of an example the stitch patterns to be produced by the invention;
FIG. 2 shows a control circuit of the invention; and
FIGS. 3 and 4 are the timing diagrams showing the operations of the control circuit in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1(A) shows a combination of patterns, a tulip of stitches and a zigzag of stitches which are stored in a memory to be alternately and repeatedly produced with a full swinging amplitude of needle and with a basic or reference needle position L within the maximum range between the right end needle position R and the left end needle position L corresponding to signals 30 and 0 respectively. The needle position M is the center of the maximum swinging range of the needle and corresponds to a signal 15. FIG. 1(B) shows the same patterns as those of FIG. 1(A), but these patterns are reduced into a half of the patterns of FIG. 1(A) in the zigzag amplitude of needle.
FIG. 2 shows a control circuit designed to produce the patterns as shown in FIG. 1(A) and FIG. 1(B), in which SW 1 is a pattern selecting device including a number of switches selectively operated to produce a pattern signal of a selected pattern to be stitched. An encoder E receives the pattern signal and produces a 3-bit code signal to a latch circuit L 1 . Vcc is a positive control power source, and R 1 denotes pull-up resistors. MM 1 is a monostable multivibrator circuit which receives the pattern signal from the pattern selecting device SW 1 through a NAND circuit NAND. The monostable multivibrator circuit has an output terminal Q to give the pattern signal to the trigger terminal of the latch circuit L 1 , so that the latch circuit may latch the code signal from the encoder E. RAM is an electronic memory for tempoarily memorize the data of the input terminal IN in the columns designated by a 4-bit address (ad) in accordance to the writing order of a mode designation terminal R/W, and for producing a signal at the output terminal OUT in accordance to a readout order.
ROM 1 is an electronic memory fixedly storing the stitch control data of patterns to be stitched, and has address terminals A 0 -A 1 , of which the terminals A 5 -A 7 receive a pattern code signal directly or indirectly from the output terminal OUT of the memory RAM. SW 2 is a memory switch which is operated to produce a falling signal to actuate a monostable multivibrator circuit MM 2 . Then the monostable multivibrator circuit MM 2 gives the output at the true side output terminal Q to a delay circuit TD 1 and to one input of AND circuit AND 1 which has another input receiving the complement side output Q. The AND circuit AND 1 has an output connected to one input of NOR circuit NOR 1 . R 2 is a pull-up resistor. The NOR circuit NOR 1 has another input receiving the output Q of the monostable multivibrator circuit MM 1 , and has an output connected to the mode designation terminal R/W of the memory RAM, so as to memorize or rewrite the signal of latch circuit L 1 into the memory RAM each time the switch SW 1 or SW 2 is operated. When the switches SW 1 , SW 2 are not operated, the terminal R/W is high level for ordering the memory RAM to read out the data. When these switches are operated, the terminal R/W temporarily becomes low level for ordering the memory to rewrite the data after a counter CT is operated by operation of the switch SW 2 to advance the addresses of the memory ROM. If the pattern selecting switches SW 1 are selectively operated more than two times without operation of the memory switch SW 2 the last switch is made effective, and accordingly the pattern data is memorized.
The counter CT is reset when the control power source is applied, and has a count-up terminal UP receiving, through OR circuit OR 1 , the output of AND circuit AND 2 which receives the true side outputs Q of the monostable multivibrator MM 2 and of the delay circuit TD 1 . The counter is operated to count up when the memory switch SW 2 is operated. L 2 is a latch circuit and has an input terminal IN receiving the count-up signal of the counter CT, and has a trigger terminal CP receiving the output signal of the memory switch SW 2 through AND circuit AND 3 , OR circuit OR 2 and monostable multivibrator circuit MM 3 , said AND circuit AND 3 receiving the complement side output Q of monostable multivibrator circuit MM 2 and the true side output Q of delay circuit TD 1 . Thus the latch circuit L 2 latches the count-up signal of the counter CT when the switch SW 2 is operated.
TB is a timing buffer having a reset terminal connected to the output of NOR circuit NOR 1 , and produces the output O each time the switches SW 1 , SW 2 are operated, and accordingly makes O the address inputs A 0 -A 4 of the memory ROM 1 . The timing buffer TB has a trigger terminal CP receiving a pulse signal of a pulse generator PG operated in synchronism with rotation of drive shaft of sewing machine (not shown), thereby to latch the address signals B 0 -B 4 and advance the address of the memory ROM 1 per stitch. The relation between the timing buffer TB and the memory ROM 1 is described in detail in U.S. Pat. No. 4,086,862 and the copending German patent application Ser. No. 26 26 322.9, both of the same applicant.
The memory ROM 1 stores the needle control data DB and the feed control data EF which are to be transmitted to calculating device PVA 1 , PVA 2 respectively. The calculating devices PVA 1 , PVA 2 receive the adjusting signals of needle swing amplitude adjusting device VRB and of feed adjusting device VRF respectively as the reduction rate data KB, KF through analog-digital converters A/D 1 , A/D 2 , and make calculations including the multiplications of the data KB, KF and the control data DB, DF respectively to produce the outputs to stitch forming device DV. When the needle control data DB is 0, it designates the needle coordinate R, and when the data is 30, it designates the needle coordinate L. Thus the maximum needle swinging range between 0 and 30 are evenly divided into 30 for so many needle coordinates. When the feed control data DF is 0, it designates the maximum fabric feeding movement in the backward direction, and when the data is 30, it designates the maximum fabric feeding movement in the forward direction.
SW 3 is a controller switch which is closed as a controller (not shown) is operated and produces a falling signal to operate a monostable multivibrator circuit MM 4 . R 3 is a pull-up resistor. The monostable multivibrator circuit MM 4 has a true side output Q connected to a set terminal S of JK type flip-flop circuit FF 1 to set the latter when the switch SW 3 is operated. The same circuit MM 4 has a terminal J grounded and of low level, and has a terminal K connected to a true side output terminal Q of the flip-flop circuit FF 1 . The flip-flop circuit FF 1 has a trigger terminal CP receiving the output Q of the monostable multivibrator MM 1 and is reset by the falling signal applied thereto. AND circuit AND 4 receives the output Q of the monostable multivibrator circuit MM 4 and the output of delay circuit TD 2 which is operated by the complement side output Q of the flip-flop circuit FF 1 . The AND circuit AND 4 has an output connected to the reset terminal R of the counter CT through OR circuit OR 3 , so at the reset the counter when the controller switch SW 3 is closed after the pattern selecting switch SW 1 is operated.
The flip-flop circuit FF 1 has the true side output terminal Q connected to a reset terminal R of the monostable multivibrator circuit MM 2 and to the inputs of AND circuits AND 5 , AND 6 . The address signals A 0 -A 4 of the memory ROM 1 are 0 for the first stitch and operate a monostable multivibrator MM 5 through the NOR circuit NOR 2 . The monostable multivibrator MM 5 has an output terminal Q connected to another input of the AND circuit AND 5 , which has the output to the count-up terminal UP of the counter CT through the OR circuit OR 1 , to start the count-up of the counter CT each time a new pattern is stitched. The AND circuit AND 6 has another input connected to the output Q of the monostable multivibrator MM 1 , and is so connected as to reset the counter CT through the OR circuit OR 3 when the pattern selecting switch SW 1 is operated after operation of the controller switch SW 3 , and is so connected to latch the value O of the counter CT in the latch circuit L 2 , and is so connected to reset a flip-flop circuit FF 2 .
Exclusive OR circuits EXOR 1 -EXOR 4 compare the signal of the counter CT and the signal OUT of the latch circuit L 2 as to the bits thereof and, if these bits are all in accord, operate a monostable multivibrator circuit MM 6 through a NOR circuit NOR 3 . The output Q of the monostable multivibrator circuit MM 6 resets the counter CT for stitching the first one of the combined patterns.
ROM 2 is an electronic memory fixedly storing the data for controlling the basic (or reference) position of the needle of sewing machine. The memory ROM 2 has the inputs G 0 , G 1 , G 2 receiving a code signal from the output terminal OUT of the memory RAM, and has an output terminal P for producing an output signal in response to the code signal to control the basic position of needle. The basic needle position control signal is low level directing the basic needle position to the center M for the ordinary stitch patterns including the straight stitches. On the other hand, the basic needle position control signal is high level for the stitch patterns including the tulip patterns as shown in FIG. 1 which require a basic needle position at the left end L of the maximum needle swing range.
The flip-flop circuit FF 2 is, as aforementioned, reset each time the pattern selecting switch SW 1 is operated after operation of the controller switch SW 3 , and has a set terminal S receiving the output signal of AND circuit AND 7 which receives the output signal P of the memory ROM 2 and the output of OR circuit OR 1 . The pattern designation due to operation of the pattern selecting switch SW 1 maintains the output P of the memory ROM 2 in high level, and the flip-flop circuit FF 2 is set when the memory switch SW 2 is operated. Namely if the patterns memorized in the memory RAM include a pattern or patterns of the basic needle position L, the flip-flop circuit FF 2 is set and the output Q becomes high level. If the memorized patterns include no pattern of the basic needle position L, the output Q remains low level.
NOR circuit NOR 4 receives the output Q of the flip-flop circuit FF 2 and the output P of the memory ROM 2 , and produces a 4-bit output as a basic needle position control code KD given to the calculation device of needle position PVA 1 . The NOR circuit NOR 4 directly receives the output P of the memory ROM 2 for the ordinary patterns not accompanied by the pattern memorizing operation. OR circuit OR 4 receives the output OUT of all bits of the memory RAM, and has the output connected to the needle position calculating device PVA 1 . In this embodiment, if the pattern selecting switch SW 1 is operated to select the straight stitches, the designation code makes the output OUT of the memory RAM 0 0 0 (the corresponding relation is not shown), and gives 0 to the calculating device PVA 1 , and gives a signal including 1 for the patterns other than the straight stitches.
The needle position calculating device PVA 1 receives the needle position control signal DB of the memory ROM 1 , the needle position reduction rate signal KB, the basic needle position control code KD and the output signal of the OR circuit OR 4 , and makes a calculation (DB-KD)×KB+KD. When the output signal of the OR circuit OR 4 is 1, the calculating device PVA 1 gives the result of the calculation to the stitch forming device DV. When the output signal of the OR circuit OR 4 is 0, the calculating device PVA 1 gives the result of the calculation as the data KD to the stitch forming device DV. The fabric feed calculating device PVA 2 receives the feed control signal DF and the feed reduction rate signal KF, and makes a calculation DF×KF, and gives the result of the calculation to the stitch forming device DV.
With the above-mentioned combination of elements, the operation of the control circuit will now be described in reference to the time charts in FIGS. 3 and 4. If one of the pattern selecting switches SW 1 is operated to select the tulip pattern as shown in FIG. 1, a falling signal is produced to operate the monostable multivibrator circuit MM 1 . Then the latch circuit L 1 is operated to latch a new data NEW in place of an old data OLD, and the temporal memory RAM is operated to memorize a new data NEW in place of an old data OLD. At this time, it is to be assumed that the address (ad) of the memory is n-1. As the flip-flop circuit FF 1 is reset with operation of the pattern selecting switch SW 1 , the AND circuit AND 6 nullifies the signal of the switch SW 1 , and therefore the counter CT is not reset and has no count-up signal.
Subsequently, if the memory switch SW 2 is operated, a falling signal is produced to operate the monostable multi-vibrator circuit MM 2 for producing a pulse signal, and then the delay circuit TD 1 is operated to produce a pulse of the same width as that of the monostable multivibrator circuit MM 2 . With the combination of the two pulse signals, the AND circuits AND 1 , AND 2 , AND 3 produce a pulse one after another as shown in FIG. 4. The mode designation terminal R/W of the memory RAM is made low level with the rising signal of the AND circuit AND 1 , and the new data NEW is memorized again at the address (ad), which is n-1, of the memory RAM. With the subsequent rising signal of the AND circuit AND 2 , the counter CT starts to count up, and the address (ad) becomes (n). With the subsequent rising signal of the AND circuit AND 3 , the latch circuit L 2 latches the output data (n) of the counter CT.
Then if another pattern selecting switch SW 1 is operated to select the zigzag pattern as shown in FIG. 1 in combination with the tulip pattern, the latch circuit L 1 latches the pattern designation signal. Subsequently if the memory switch SW 2 is operated, the memory RAM is ordered, through the AND circuit AND 1 , NOR circuit NOR 1 , to memorize the pattern designation signal at the address (n) thereof. In the same manner, the counter CT starts to count up, and the address (ad) becomes n+1. With such alternate operations of the switches SW 1 , SW 2 , the memory RAM is inscribed with the pattern data with advance of the addresses, and the latch circuit L 2 latches the output data of the counter CT as a total number of patterns to be stitched. In this embodiment, it is to be assumed that the tulip and zigzag patterns have been memorized in combination as shown in FIGS. 1(A) and 1(B).
With the aforementioned selection of the tulip pattern, the basic needle position control signal P of the memory ROM 2 is high level, and the flip-flop circuit FF 2 is set with the subsequent operation of the memory switch SW 2 and by way of the AND circuit AND 2 , OR circuit OR 1 , AND circuit AND 7 . With the aforementioned subsequent selection of the zigzag pattern, one input of the AND circuit AND 6 is high level, but the flip-flop circuit FF 2 is not reset because the flip-flop circuit FF 1 is reset. Therefore, after the selection of the first pattern, the basic needle position control code KD of the calculating device PVA 1 remains 0 0 0 0, i.e., decimally 0.
Then if the machine controller (not shown) is operated to close the switch SW 3 , the flip-flop circuit FF 1 , is set. Then the counter CT is reset, and the address (ad) of the memory RAM becomes 0. This corresponds to the initial address of the stitch control data of the first tulip pattern stored in the memory ROM 1 , and is mentioned hereinbefore as the address n-1. The calculating devices PVA 1 , PVA 2 respectively receive the needle position control data DB and the feed control data DF read out from the memory ROM 1 at the initial address A 7 -A 5 of the address signal A 7 -A 0 (the rest are all 0) of the tulip pattern, and the corresponding reduction rate data KG, KF respectively of the needle swing adjusting device VRB and the feed adjusting device VRF. The calculating device PVA 1 further receives the basic needle position control code KD as 0 0 0 0 and the signal 1 of the OR circuit OR 4 , and makes a calculation (DB-0)×KB+0 and gives the result to the stitch forming device DB.
As the sewing machine is rotated, the pulse generator PG is operated in synchronism with rotation of the drive shaft of sewing machine and produces a timing pulse. The first pulse reads out the data DB, DF from the initial address of the memory ROM 1 for the first stitch, and correspondingly the address data B 4 -B 0 are read out and latched at the timing buffer TB for the address input A 4 -A 0 of the second stitch. Thus the stitches are progressively produced as the sewing machine rotates. As the address data DB, DF are O, which are read out together with the stitch control data DB, DF for the last stitch of the unit pattern, the counter CT counts up. Then the memory RAM designates the initial address of the next zigzag pattern of the memory ROM 1 . The stitches are similarly produced, and the counter CT counts up. When the value of the counter comes to be in accord with the total number of patterns latched in the latch circuit L 2 , the monostable multivibrator circuit MM 6 is operated to reset the counter. Therefore, the stitch is returned to the first one of the tulip pattern, and the combination of patterns is repeatedly produced. As the basic needle position control code KD and the output of OR circuit OR 4 are constant all through the production of stitch control data DB, DF in formation of the two stitch patterns, the calculations (DB-0)+0=DB is obtained in case the needle swing reduction rate KB by the needle swing adjusting device VRB is 1, and as the result, the maximum (not reduced) combination of patterns is produced as shown in FIG. 1(A). If the reduction rate KB is 0.5, the calculation (DB-0)×0.5=0.5 DB is obtained, and as the result, the combination of patterns is produced as shown in FIG. 1(B) which is 1/2 of the needle swing amplitude with the basic needle position L. With respect to the feed control, the theory is the same with that of the needle position control and therefore the explanation is omitted here.
If the pattern of straight stitches is selected in place of the zigzag stitch pattern to be combined with the tulip pattern, the flip-flop circuit FF 2 is set due to the property of the tulip pattern, and the basic needle position control code KD is 0 0 0 0 and the tulip pattern is produced in the same manner as above-mentioned. Upon subsequent stitching of the straight stitches, the output OUT of the memory RAM is 0 0 0, and the output of the OR circuit OR 4 is 0. The output of the calculating device PVA 1 is 0 0 0 0 which is the data of the basic needle position control data, and the basic needle position is shifted to the position L irrespectively of the stitching process and the adjustment by the adjusting device VRB.
As to the formation of these three patterns individually, the memory switch SW 2 is not operated, and therefore the flip-flop circuit FF 2 is not reset. Since the NOR circuit NOR 4 directly receives the output P of the memory ROM, the basic needle position control signal KD is 0 0 0 0 for the tulip pattern, and 1 1 1 1 for the other patterns. Therefore, the tulip pattern is formed in the manner as aforementioned. As to the zigzag pattern, the output of the calculating device is (DB-15)×KG+15, and the result is DB when the reduction rate KB is 1, and the maximum zigzag pattern is produced as shown in FIG. 1(A). If the reduction rate KB is 0, the result of calculation is 15, and the zigzag pattern is reduced on the center basic needle position M. As to the straight stitches, the basic needle position control signal KD is 1 1 1 1, and the output of the OR circuit OR 4 is 0. The output of the calculating device PVA 1 is therefore 1 1 1 1 which is the same value with the data KD. Thus, the straight stitches are formed on the center basic needle position M. | A plurality of different stitch patterns are stored in a first static memory. A second static memory memorizes a combination of these different patterns in a predetermined sequence. A third static memory stores basic needle position signals each specific to the patterns stored in the first memory. Calculating means utilize signals derived from the second memory and the third memory to determine values for adjusting the swinging amplitude of the sewing needle with a common variation rate and for setting a common basic needle position. | 3 |
This application is a continuation of application Ser. No. 08/020,915, filed Feb. 22, 1993, now abandoned.
FIELD OF THE INVENTION
This invention relates to hinges and more particularly to torque hinges.
BACKGROUND OF THE INVENTION
The use of hinges for the opening and closing of various apparatus is notoriously well known. Torque hinges are a subset of hinges that allow an apparatus to have resistance throughout the apparatus' entire range of motion.
In electronic markets, torque hinges have been utilized in a number of areas. One example is the notebook computer. Torque hinges are desirable because a user wishes to open the computer and use the top lid portion as a computer display. Because users all differ in height and in location during use of the computer, it is desirable to be able to open the lid of the computer and hold the lid of the computer at various angles to maximize a users' visibility, avoid a glare, etc. A torque hinge provides constant resistance throughout the computer lid's range of motion and is therefore ideal for this application.
A conventional, prior art spring torque hinge 10 is illustrated in FIG. 1. A spring 12 is wound around a shaft 14. Spring 12 has two ends 12a and 12b that are connected to a clasp 16 that holds the compression of spring 12 fixed. Spring torque hinge 10 has what is referred to as an interference fit. An interference fit comprises two articles; one designed to fit within the other. The article that is to fit within the other is designed to be slightly larger than the opening of the other article. For example, with spring torque hinge 10 the inside diameter of spring 12 is slightly smaller than the outside diameter of shaft 14 such that when spring 12 is wrapped around shaft 14 the "interference" between spring 12 and shaft 14 causes the necessary friction for continuous resistance through shaft's 14 range of movement.
Spring torque hinge 10 suffers from a serious problem. Over time, spring 12 loses its original "tightness", or uniformity, and begins to assume the diameter of shaft 14. This is undesirable since this results in decreased friction between spring 12 and shaft 14. Therefore, the desired resistance, or torque, is not maintained over time. Testing of a standard torque hinge (10,000 actuations) resulted in spring torque hinge 10 losing more than 50% of its initial torque.
It is an object of this invention to provide a new hinge that provides improved wear over time, improved frictional characteristics, increased life, and decreased cost. Other objects and advantages of the invention will be apparent to those of ordinary skill in the art having reference to the following specification and drawings.
SUMMARY OF THE INVENTION
An interference fit torque hinge includes a shaft surrounded with a coating. The coated shaft fits within a housing cavity such that the coated shaft is in frictional contact with the housing cavity. The frictional contact provides sufficient torque to the torque hinge to provide constant resistance through the torque hinge's entire range of motion and improved reliability by maintaining its torque throughout a product's lifetime.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a prior art drawing illustrating a spring torque hinge.
FIG. 2 is the preferred embodiment of the invention, a foam type, interference fit torque hinge.
FIG. 3 is an alternative embodiment of the invention.
FIG. 4 is another alternative embodiment of invention.
FIG. 5 is a diagram illustrating a computer incorporating the preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 2 illustrates the preferred embodiment of the invention, namely a foam type, interference fit torque hinge 20. Shaft 14 is surrounded by a coating 22. Coating 22 is applied to shaft 14 using any appropriate process. Coating 22 is fixed to shaft 14 such that coating 22 moves radially with shaft 14 as shaft 14 is manipulated. Shaft 14 and foam 22 fit into a cavity 26 within a housing 24. Hinge 20 is designed such that outside diameter "Y" of shaft 14 is smaller than the inside diameter "Z" of cavity 26. Also, the outside diameter of coating 22 "X" in FIG. 2 is designed to be larger than the inside diameter "Z" of cavity 26. It is obvious that since "X" is larger than "Z" that coating 22 must be compressive in order to fit within cavity 26 of housing 24. The compressive force of coating 22 against cavity 26 coupled with the coefficient of friction between coating 22 and housing 24 defines the torque provided by hinge 20.
Hinge 20 of FIG. 2 showed substantial improvement over prior art interference fit torque hinges such as hinge 10 of FIG. 1. One variable that is measured is the resistance to compression set which is defined as the ability to maintain its original torque over time. Therefore, a high quality torque hinge will maintain a high percentage of its original torque throughout its lifetime. Hinge 20 was tested by performing 30,000 actuations and measuring the torque at varying intervals. Results showed that after 30,000 actuations (considered a product lifetime) hinge 20 maintained 92% of its original torque while prior art hinge 10 of FIG. 1 had lost torque consistency; the maximum torque being less than 50% of its original torque after only 10,000 actuations.
Coating 22 of hinge 20 may be preferably composed of microcellular urethane (MCU) foam. MCU foam provides high endurance properties as shown in the above testing thereby exuding excellent wear characteristics. MCU also provides dimensional stability as shown in the ENDUR®-C Microcellular Urethane Products Data Sheet printed in 1987 by Rogers Corporation which is hereby incorporated by reference. MCU also exhibits good chemical, heat, and ozone resistance while concurrently being lower cost than conventional torque hinge 10. Specifically, the current cost for a prior art spring type interference fit torque hinge is approximately $4.50. Using two hinges per product, the total cost for the hinges is $9.00 per product. The new hinge 20 of FIG. 2 costs approximately $2.00. Therefore, the total cost for the hinges per product is only $4.00 which represents a savings of $5.00 per product or a cost savings of 55%.
Other types of foams may be used in replacement of MCU foam. Furthermore, coating 22 does not have to be a foam. Coating 22 may consist of teflon or silicone or any compressive substance that would provide suitable friction between coating 22 and housing 24. To vary the torque one may increase or decrease the length of shaft 14 and coating 22 making contact within cavity 26 of housing 24 or by increasing or decreasing the thickness of coating 22 or varying the inside diameter of cavity 26 thereby increasing the compressive force in hinge 20. Further, the material density of coating 22 may also be varied.
An alternative embodiment of the invention is illustrated in FIG. 3. In FIG. 3, a hinge 30 consists of a coating 22 fixed inside cavity 26 of housing 24. Therefore the outside diameter of coating 22 will be equal to the diameter of "Z" of cavity 26. The inside diameter "X" of coating 22 is not shown because FIG. 3 illustrates coating 22 compressed. Shaft 14 has a diameter "Y" that is larger than the inside diameter "X" of coating 22. This physical relationship causes coating 22 to compress and create frictional contact with shaft 14 when shaft 14 is inserted inside coating 22. The compressive force between shaft 14 coupled with the coefficient of friction between shaft 14 and coating 22 forms the torque of hinge 30. Coating 22 would preferably consist of microcellular urethane foam (MCU) but may consist of other types of foam or other compressive materials such as silicone or teflon. Increasing or decreasing the desired torque may be obtained by increasing or decreasing the contact length between coating 22 and shaft 14 in housing 24, varying the material density of coating 22, or varying the thickness of coating 22.
FIG. 4 is another alternative embodiment of the invention. In FIG. 4, a hinge 40 includes coating 22 not fixed to either cavity 26 of housing 24 or shaft 14. In this embodiment the outside diameter "X" of coating 22 is larger than the diameter "Z" of cavity 26. Therefore, there is a compressive force between coating 22 and housing 24 and therefore frictional contact. The inside diameter W of coating 22 is designed to be smaller than the diameter "Y" of shaft 14. Therefore, when shaft 14 is inserted into coating 22, coating 22 is further compressed and shaft 14 will be in frictional contact with the inside surface of coating 22. Therefore, hinge 40 has a torque provided by two components: one, the compressive force between shaft 14 and coating 22 coupled with the coefficient of friction between the two respective materials and two, the compressive force between coating 22 and housing 24 coupled with the coefficient of friction between the two respective materials. This provides more design flexibility since the compressive forces can be manipulated by adjusting the diameters of the shaft, coating, or housing and the coefficient of friction can be manipulated by varying the materials used for shaft 14, coating 22, and housing 24. The coefficient of friction may also be adjusted by varying the material densities of shaft 14, coating 22, and housing 24. In hinge 40, coating 22 preferably consists of MCU foam. Other types of foam may be substituted for MCU foam. Further, other types of compressive materials other than foams may be used for coating 22.
It should also be noted that although FIGS. 2, 3, and 4 illustrate torque hinges with cylindrical shafts 14, coatings 22, and cavities 26 that the invention is not limited to this configuration. For ease of design or manufacturability it may be useful to have a cylindrical cavity 26 with an octagonal shaft 14 and coating 22. All shape variations of cavity 26, coating 22, and shaft 14 would fall within the spirit of this invention.
Although the invention has been described with reference to a preferred embodiment and alternative embodiments herein, this description is not to be construed in a limiting sense. Various modifications of the disclosed embodiments will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention. | A torque hinge 20 includes a shaft 14 surrounded with a coating 22 fixed to the shaft 14. The coated shaft 18 fits within a housing cavity 26 such that the coated shaft 18 is in frictional contact with the housing cavity 26. The frictional contact provides sufficient torque to torque hinge 20 to provide constant resistance through the torque hinge's entire range of motion. | 4 |
RELATED APPLICATION
[0001] This application continues from U.S. Provisional Patent Application Ser. No. 60/618160, filed Oct. 13, 2004, of same title and inventors, which application is incorporated by reference herein for all purposes.
GOVERNMENT INTEREST
[0002] The Government has certain interests in this invention pursuant to Contract Nos. NAS3-00080 and NAS3-01015 (NASA), and DG1330-02CN-0058 and 50-DKNA-1-90041 (NOAA).
FIELD OF THE INVENTION
[0003] The invention in general relates to high performance and efficient membrane systems, and more particularly relates to three dimensionally reinforced inflatables/deployables made with plural shaped and joined membrane segments.
[0004] Three applications: Near space platform & vehicles (alt 65k to 150k) incl. high altit airship hulls and components such as fins, load patches & other local reinforcements; heavier than air craft (fuselage, wings, stabilizers & control surfaces); incorporating sensors and controls into “smart structures”.
BACKGROUND
[0005] Terrestrial and space inflatables—like balloons—are traditionally constructed by joining a series of specially shaped flat gores to approximate the desired three-dimensional shape. With typical gore construction, the most severe localized load determines the materials'areal density. To improve the fidelity of the shape and the resultant localized loads, additional gores and seams may be added. However, additional seams increase the structural discontinuities, affecting reliability and significantly impacting weight and cost.
[0006] Although a wide variety of materials and sealing/joining equipment may be applied, almost all inflatable and deployable membrane fabrication methods involve joining specially shaped flat gores (i.e., shaped segments, typically roughly triangular-shaped) to form the desired three-dimensional shape. A hot wheel sealer is typically used to join polyester (Mylar) film gores in a heat-activated adhesive bi-taped seam. This type of seam construction has been used on thousands of polyester superpressure balloons, and bi-taped seams are considered generally reliable.
[0007] The gores themselves are typically constructed from a relatively uniform material. Load patches or doublers may be applied to specific load attachment points and end fittings. But, if used, fiber reinforcements typically take the form of either a fabric or a scrim laminated to the entire gore material or individual load tapes that run along the gore seams connecting the top and bottom end fittings. In either case, the most severe localized load determines the areal density of the gore material. Providing an adequate safety factor for this localized load means that the gore is considerably heavier than is necessary elsewhere.
[0008] Moreover, this traditional approach to inflatable design creates several problems for cost effective high performance applications. First, the existing method of reinforcement adds unnecessary weight while only addressing the worst case loading condition; this limits the payload that can be carried. Second, the production of seams, in order to manufacture the inflatable's envelope, creates stress concentrations in the envelope structure. Third, there are multiple load configurations that a system could see during deployment, inflation or flight, but current designs only deal with one well, leaving inefficient solutions for the others. Finally, the packing volume is excessive, since structures are currently created in their final three dimensional shape and then compressed for transit.
[0009] Just such a solution to the problems noted above and more, are made possible by our invention disclosed below.
SUMMARY
[0010] An illustrative summary of the invention, with particular reference to the detailed embodiment described below, includes an apparatus and method for making high performance inflatables and deployables using three dimensionally reinforced (3DR) membranes. A 3DR process preferably takes plural substantially flat gore segments, each segment made of plural membranes and reinforcing fibers, and joins adjacent gores so the seams on opposite sides are offset. Single ply seam tape may be used. When all gores are joined, a three dimensional deployable or inflatable (e.g., balloon) structure with a minimized seam is produced. Further, localized fiber reinforcement is preferably used, with different characteristics (e.g., moduli, tension) depending on the desired placement in the gore, allowing the substantially flat gores, when joined and loaded, to strain to the desired three dimensional shape. In doing so, the required number of gores and seams may be reduced, while using materials with significantly lower areal densities. The 3DR process thus allows one to make locally reinforced materials that optimize strength to weight ratios; permits single ply width seam tapes; permits multi-phase optimized envelope shapes, designed to efficiently handle multiple loading conditions (storage, deployment, inflation, and multiple flight configurations); and provides increased design flexibility for a wide range of shapes and characteristics impractical or unavailable under prior techniques.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Our invention may be more readily appreciated from the following detailed description, when read in conjunction with the accompanying drawings, in which:
[0012] FIG. 1 illustrates a bi-taped seam such as that used in prior art techniques for joining segments of inflatables and deployables, with FIG. 1A showing a top view and FIG. 1B showing a cross-sectional view along the line A-A′.
[0013] FIG. 2 illustrates an offset-gore seam according to a first embodiment of the invention, with FIG. 1A showing a top view and FIG. 2B showing a cross-sectional view along the line A-A′.
[0014] FIGS. 3 through 7 illustrate steps in a process for the manufacture of a gore according to the first embodiment of the invention, where FIGS. 3A, 4A , 5 A, 6 A and 7 illustrate top views of a gore in progressive stages of manufacture, and FIGS. 3B, 4B , 5 B and 6 B show cross-sectional views along the line A-A′ for the respective top views;
[0015] FIG. 8 is a perspective view of a prior art inflatable; and
[0016] FIG. 9 is a perspective view of an inflatable with plural gores made according to the process of FIGS. 3 through 7 .
DETAILED DESCRIPTION
[0017] A more adaptable, low cost, and lighter weight deployable system is now possible through our invention, a presently preferred embodiment of which is the three dimensionally reinforced membrane (3DR) process and apparatus described below. By “deployable” we mean any one of the class of apparatuses using pressure-filled (e.g., inflatables like balloons) or pressure-displaced membranes (e.g., solar sails) to affect the location of a load (e.g., instruments) attached to the membrane structure.
[0018] There are two basic phases for production of 3DR deployables: membrane production, and sealing/joining. The membrane production process encompasses the design, placement, and laminating or curing (as required) of fibers and film. Different adhesives and adhesive types are accommodated with different dispensing systems. The seaming/joining process can be performed in two or three dimensions depending on the requirements of the finished shape or the joint construction. The sealing heat and pressure sources used depend on the desired seam configuration. A conventional near-IR (infrared) heater may be used in conjunction with vacuum bagging, supplemented by other existing sealing means such as a hot wheel sealer or manual heat sealer.
[0019] A 3DR deployable can be made either by special molds or a mold-less process. In the mold-less process, plural substantially flat gores are formed with top (outer) and bottom (inner) membranes joined via fibers, with edges of the top and bottom membranes offset from each other. When joining gores, the seams formed by adjacent outer membrane edges are offset from the seams formed by the adjacent inner membranes, preferably with one or more fibers being positioned between the offset seams. In a three-dimensionally molded process, adjacent gores membranes can be formed and seamed using an uninterrupted group of fibers common to each of the adjacent gores. In either case, the characteristics can be varied for different fibers used in the gores to achieve varying characteristics for the deployables.
[0020] Because significantly increased payloads for smaller size/areal density inflatables for high-altitude terrestrial applications, the 3DR inflatables now make possible a variety atmospheric in-situ (i.e., near-stationary in very high altitudes (15, 20 or more miles) with low atmosphere/low winds), long duration investigations for terrestrial atmospheric and climate studies, commercial applications like wireless communications and remote sensing, and military uses.
[0021] To help understand the 3DR system, FIG. 1 illustrates a bi-taped seam approach such as might be found in conventional high-altitude balloon construction. In this prior art approach, the balloon 100 is made up of plural gores 110 , 120 , each gore having outer 111 , 121 and inner 113 , 123 membranes, respectively, coated with adhesive 124 , and latitudinal 112 , 122 , and longitudinal 115 , 125 fibers. The inner and outer membranes form a common edge 130 in both gores. When joined, this edge is particularly susceptible to strains and early failure, so outer and inner tapes 131 , 132 are joined (glued) along the length of the common edge to form seam 130 . While seams of this type can be made sufficiently strong to successfully join the gores, they have all the attendant shortcomings noted above in connection with prior art deployables. These shortcomings are particularly limiting in high-altitude deployables (i.e., deployables designed to carry loads at heights greater than 10 km in the atmosphere or in space) like airships or superpressure balloons where the more limiting structure and payload weights limit the overall utility of the deployable.
[0022] By contrast, FIG. 2 shows two gores joined using the offset gore structure according to a presently preferred embodiment of the 3DR system. In this approach, the deployable 200 is similarly made up of plural gores 210 , 220 , each gore having outer 211 , 221 and inner 213 , 223 membranes, respectively, and latitudinal 212 , 216 , 222 , 226 and longitudinal 215 , 225 fibers. However, the outer membranes form a common edge 230 which is offset from the common edge 240 formed by inner membranes 213 , 223 . This process provides a near-seamless joint without the requirement for additional reinforcement.
[0023] By near-seamless, we mean a joint having a seam tape which seals adjacent membrane edges, such that the tape has a depth substantially (e.g., 20%, 50%, or even 75%) less than the depth of the gore (i.e., between the gore's inner and outer surfaces). In 3DR systems where the entire fiber is coated (e.g., see adhesive 224 on fiber 226 ), and one or more fibers join the membranes between each offset joint, a seam tape could be entirely dispensed with since the fiber(s) form a sealed lamination between offset seams. Nonetheless, one may still want to use the seam tapes to provide a back-up gas barrier, at least for one side of the inflatable. In systems where the fibers are only spot-welded e.g. where fibers overlap, the welds still provide the major load-bearing features but the seam tapes are preferred (over alternatives like continuous sealant joining the edges with each other and/or the opposite membrane) for forming the seal barrier.
[0024] A “mold-less” process for making 3DR gores may be advantageously used in scaling up to extremely large structures, and is specially suited for high-altitude inflatables. In this process, each gore is made substantially flat, such as illustrated by FIGS. 3 through 7 . Starting with FIG. 3A , a first sheet of membrane material 311 is laid out on a forming surface (in this case a flat surface), and fibers in a first orientation (e.g., latitudinal fibers 312 - 314 ) are positioned on the membrane. The fibers can be placed uniformly, but for many inflatables a non-uniform spacing may be preferred to achieve optimal load-bearing characteristics. For convenience, the resulting structure can be referred to as the inner panel 310 (i.e., where this panel is designed to be on the inside of the inflatable in the final assembly). As a practical matter, because the membranes for almost all inflatables will be narrow, the inner and outer panels will be the same size, just offset. Alternatively, one panel could be designed to overlap both edges of the other (the panels assembled with the overlapping panel alternating as inner then outer), or an inner panel could be designed as a different size (e.g., slightly smaller) than the outer panel. In the case of deployables that are not inflatables (e.g., solar sails), adjacent panels may vary significantly, depending on the final shape desired for the deployable. The panel is cut using any suitable cutting method to the specified curvature required by the design.
[0025] In FIG. 4 , longitudinal fibers 315 , 316 are laid on top of the inner panel in a desired orientation (preferably in arcs defined by common end points at (or beyond) the two ends of the panel 310 for inflatables). Next, in FIGS. 5 and 6 , latitudinal fibers 322 - 325 of outer panel 320 are laid on top of inner panel 311 /longitudinal fibers 315 , 316 , and outer membrane 321 is laid on top of the latitudinal fibers 322 - 324 . The latitudinal fibers may be in any desirable orientation, but may be conveniently laid in complimentary spacing with respect to inner and outer panel fibers, so as to minimize the number of fibers required. The fibers and membranes are joined to each other by local bond, whether by application of an adhesive or (if permitted by the fiber properties) by welding (e.g., hot wheel) or other bonding (e.g., pressure sensitive) technique. In order to minimize the adhesive weight, spot welding may be done so that adhesive is only applied at fiber intersections (selected ones, or all), such that the intersections are joined to each other and the two membranes. Alternatively, the length of the fibers can be coated with adhesive such that the membranes and other fibers adhere to each fiber along its length.
[0026] Finally, in FIG. 7 , any suitable cutting method is used to trim excess membrane from the inner and outer panels. For most inflatables, most top membranes will be pre-trimmed (e.g., to the same shape shown in FIG. 4A for membrane 311 ) before being placed on the fibers. Both panels of the gore (see FIG. 6A ) are then trimmed to leave opposite extending edges on both sides of central gore structure (defined by the portion two-membrane wide), with one offset edge part of the inner panel and the other offset edge part of the outer panel. In this manner, an alternating inner/outer panel extension/offset structure is produced, allowing complimentary extending portions from adjacent gores (e.g., 810 , 820 ) to be joined to form a continuous structure (e.g., the ellipsoidal balloon 800 shown in FIG. 8 ). This process can also be done with pre-cut outer and inner films using the previously defined sequence with attention paid to the exact placement of each film layer.
[0027] The complimentary extending portions are joined in similar manner as opposite membranes of the same gore (i.e., spot welding, adhesive along the length of fibers, adhesive along the extending edge, adhesive on the seam tape, etc.) Depending on the structure geometry, the final or closing joint is made with the same technique (i.e. offset gore joint). The joints are made on simple curve, compound curvature, or flat vacuum backing fixtures. These fixtures may be designed so they are readily removed from the hole at the apex or nadir of the final inflatable. The holes may then be sealed with traditional techniques (e.g., balloon doubler techniques), although the doubler materials are preferably pre-fabricated on the 3DR gantry to again take advantage of the ability to place fibers where the load transition stress risers will be, in order to minimize localized stress and to create a gradient of stress into/out of the entire structure.
[0028] While it is possible to lay fibers in any orientation suitable to achieve the particular load and structural characteristics desired, in a typical inflatable (balloon) the fibers will be criss-crossed in a longitudinal and latitudinal formation, like that shown in FIGS. 4-8 .
[0029] By “fibers” we mean any load-bearing filament, yarn, string or the like, whether from plants, metals or man-made materials, as suitable for the particular environment(s) and uses for which the deployable is designed. The actual membrane materials, fibers and adhesives used are a matter of design choice, that will vary depending on the nature of the deployable desired. For high-altitude inflatables, some of the materials that may be suitable as membrane and tape materials include a PET (Polyethylene Terephthalate) film (Dupont Mylar A & C, generic type A) and PVF (polyvinyl fluoride) films.
[0030] Examples of suitable fibers include Twaron (generic Kevlar), Spectra (UHMWPE-ultra-high molecular weight polyethylene), Zylon (PBO-Poly(p-phenylene-2,6-benzobisaxazole)), and Vectran (polyester-polyarylate) fibers. These appear to offer significantly better physical performance over aramids (while these may have other property concerns, when used with thin films, the fiber strength is the dominating factor combined with the specific trajectory paths used). Examples of suitable adhesives include PET, silicone & polyurethane adhesives.
[0031] In some applications, it may be preferable to use three dimensional molding to achieve the desired gore shape. One such technique for three dimensional molding is taught in U.S. Pat. No. 5,097,784 to Baudet. Here, a continuous, adjustable mold (up to 50 meters) is used for placing appropriately shaped load bearing yams between one or more inner/outer panels, to form a fixed shape sail. The inner layer of yarns are continuous from one edge of the sail to another (e.g., converging at one of the three corners), to better carry the majority of the wind load on the final sail. In the process of laying the yams, an adjustable three dimensional mold is used to hold the panel(s) in the desired shape, and a processor controlled gantry is disclosed for laying each continuous yam in the desired shape. By appropriate algorithmic control (which a skilled artisan could readily adapt for different geometries and lay characteristics, as desired), a variety of different patterns can be laid with the yarn.
[0032] The technique described in the Baudet patent is not directly applicable to the fabrication of space/high-altitude deployables, since it discloses technology aimed at sea level sailing (e.g., adhesives with a limited range of temperatures, limited geometries (no full or even hemi-ellipsoidal mold/structure), size capacity appropriate only for sailing boats, and no adequate means for scaling up processes and functionality for integrating large-scale inflatable assemblies. Nonetheless, this three dimensional technique may be usefully applied in three dimensional molding of gore segments for high-altitude deployables, with appropriate modifications. In such a case, it would not be a single, triangular wind sail that is formed, but one or more gores (or the joinder of plural gores) formed by means of varying three dimensional molds. Instead of sail yarns, lighter and variable fibers could be used. As noted above, only fiber coating or spot welding is needed to join the membranes and fibers—unlike the Baudet patent, which teaches applying adhesive to the entire panel to form a continuous laminate. But, fibers may be similarly laid for a given gore, by use of a gantry assembly or plotter to position the fiber as it is rolled onto the lower membrane (already on the mold).
[0033] When using a mold and fibers extending through plural gores, it is also possible to implement single membrane gores. In this case there is no offset, and tapes are required to form a gas seal, but the cross-gore load is still substantially borne by the inter-gore fibers.
[0034] Additionally, a 3DR deployable can be designed so each gore strains under load into the desired three-dimensional shape. This is accomplished by the choice of membrane, and reinforcing the membrane using specific fiber characteristics (e.g., varying moduli, tension, etc.) and geometries (trajectory shape and spacing). In controlling localized fiber reinforcement, the gore's properties can be varied spatially such that the gore will strain into a predetermined three-dimensional shape when placed under load. Thus, the structures can be designed to efficiently handle dramatically different loading conditions. In this way a 3DR deployable will provide significantly better performance than conventional techniques, where a significantly higher areal density material is required to provide adequate safety margins for a worst case condition (e.g., deployment) which is not the same as the condition for which the shape has been optimized (e.g., operation at a first altitude). Because the characteristics can be modeled beforehand, and automated control applied to vary placement and selection of individual fibers, a vast array of different shapes and characteristics are now possible across different operational conditions. For example, by using flat gores an optimal packing is possible, while decreasing latitudinal fiber moduli allows for a more gradual increase of the structure size during deployment, with the final (largest/widest) structure only following full deployment. Virtually any shape can be achieved, with greater fidelity and fewer gores than any prior art technique.
[0035] Further, in 3DR , the length, tension, and modulus of the fibers used in construction control the shape of the inflated envelope. Thus, the film need only serve as a low permeability membrane (by low permeability membrane, we mean a membrane that will take shape and strain, applying force against a load, in response to a gas, solar particles or the like; it need not be impermeable, although the lower the permeability the better the efficiency). This, combined with the offset gore joint, minimizes the physical mass of the system at joints, giving the system a near-seamless appearance. This also allows the film to be produced and packed as a substantially lay flat component. This flat initial shape with minimal voids results in a smaller packing volume for transit. Upon inflation, the system deforms to the 3-D shape dictated by the fiber structure.
[0036] Case Study 1. In a first space/planetary deployable design scenario, 3DR was considered in comparison to a Mars MABVAP (NASA-JPL's Mars Aerobot Validation Program) style mission. Some of the more significant environmental design conditions taken into account include a wide temperature range (55° C. to −128° C., for tensile property and permeability testing), extended duration as a packed balloon system (for months), and float at expected superpressure levels. A MABVAP base design typically consists of a 12.2μ-12.7μ polyester terepthalate (PET) film constructed with heat activated bi-taped seams of 12.7μ PET tape with 12.7μ of polyester adhesive. For this example the system design consists of a 10 m ø sphere with a float payload of 1.5 Kg, and a deployment payload of 20 Kg. Typical design areal density, weight and size is shown in the first column of Table 1.
[0037] The potential 3DR improvements for the planetary case are illustrated by column 2 of Table 1, using a PET film and aramid fibers. As is shown, initial testing indicates significantly smaller size, weight, density, and construction elements (hence cost) are required to achieve the same payload target as a conventional inflatable. Ultra-thin inflatables are also possible, with film thicknesses less than 3μ and two-sided laminate gore thicknesses less than 10μ.
TABLE 1 Comparison of Balloon Properties Property Baseline Design 3DR Design Number of gores 16 16 Balloon Diameter, (m) 10 7 Balloon Volume (m 3 ) 524 186 Float Pressure Alt. (mb) 12.3 12.3 Wt. of gore film (g) 5,334 2,761 Wt. of seams/fibers (g) 1,347 50.72 Net Wt. fittings (g) 3.85 3.85 Total weight (g) 6,684.9 2,816 Areal Density, (g/m 2 ) 21.23 8.95 Film Thickness (μ) 12.2 6.3
[0038] Case Study 2. A second target mission considered terrestrial applications based on the NOAA GAINS (Global Atmosphere-ocean IN-situ observing System) platform. The base balloon design for GAINS is a 147 gr/m2 Spectra fabric external shell with two 25.4μ polyurethane bladders inside. The associated valves and fittings are typical high altitude scientific balloon components. Inside the inner bladder is the lifting gas, while between the inner and outer bladders is the additional air ballast required to adjust the desired float density. The significant mission conditions include: extended duration radiation effects at float, temperature range, and creep. The one-year duration of the GAINS mission at 18 km float altitude exposes the 3DR structure to a significant dose of ultra-violet radiation. Using accelerated aging test equipment; 3DR laminates were tested for various durations up to the one-year maximum duration of the mission. The temperature range for this mission is +21° to −80° C.
[0039] In the GAINS terrestrial study, the films evaluated were thicker than those used for planetary MABVAP work, and also included several different types of base materials. Film thicknesses from 25.4μ to 88.9μ were considered. The films included polyvinyl fluoride (PVF), PET, and some specialty packaging films. In the end, significant areal density reductions were achieved, ranging from 28 to 36% compared to the base design. To expedite design considerations, automated tools should be used. For example, a FEA (finite element analysis) modeling design set of algorithms, and software tools may be advantageous when considering specific design variations. Results from FEA model runs have indicated that the use of different fibers and/or different moduli within a particular trajectory scheme could offer advantages. Used in conjunction with trajectory schemes that provide more uniform loading of the balloon during the various load conditions, different moduli could also have a positive impact on the areal density.
[0040] Those skilled in the art of geometric modeling of mechanical properties can design a variety of different tools without undue experimentation, tailored to specific mission goals, to determine satisfactory and optimal deployable design alternatives. Similarly, a skilled artisan could readily design appropriate control software for multi-axis (3, 6 or more, if desired) robotic gantry control to achieve predetermined, accurate placement of fibers on the membranes (whether flat or shaped), as well as particular fixtures for sealing (depending on the type, e.g., whether adhesive is continuously deposited when laying fibers, applied to detected fiber intersections, etc.), vacuum bagging, heating/laminating, lay-up and lamination tables, and the like, with variations dependent on the design objectives.
[0041] Production rates and quality may be effected by factors such as proper storage/pre-conditioning of selected materials, vacuum achieved prior to lamination, use of release films, and time/temperature/dwell differences in gore lamination and sealing. Typical balloon processing concerns may include cleanliness, station marks and alignment, static control, and film tension (removal of air and wrinkles). Minimum ambient and tooling temperatures, and maximum water vapor levels, may need to be determined and maintained for quality gore/seal production. Tensile tests may be a good indicator of lamination and seal quality, while testing on the permeance and gas transmission rates (GTR) at room temperature may correlate well with service temperature (potentially facilitating testing of material lots for consistency).
[0042] Prior approaches produced structures that had stress risers at the apex of the structure. With 3DR technology it is possible to eliminate most stress risers and provide a gradient dispersion of force across apex areas. Likewise, seam fiber transition was disjointed, not smooth, resulting in stress that could not transition across the seam and early failures. 3DR offset gore joints now permit the alignment of seam/joint fibers to facilitate stress transfer across the discontinuity of a joint, while reducing the mass in the seam. Testing has shown that the offset gore joint will produce a seam that is as strong as the parent material and as strong or stronger than a bi-tape seam.
[0043] When fabricating a gore, in the case where continuous adhesive is used on the fibers, some of the useful fabrication practices include: (i) condition (dry) the fibers, for selected ones at least 48 hours minimum; (ii) pre-cut one or both sides of the gore to the required curvature; (iii) pre-cut two pieces of release film with same curvature as gore edge and of a width appropriate for the seam width. (i.e., for a 1″ wide seam cut a 2″ wide release strip); (iv) place a base vacuum bag layer on the 3DR table and tension it so there are no wrinkles; (v) place a lower film layer in proper position with respect to a 0,0 mark (X position); (vi) using clean (cotton) gloves remove all wrinkles from film and remove all trapped air pockets between base film and lower gore film; (vii) if fibers are not pre-coated, mix up an appropriate adhesive system and load the adhesive head and/or adhesive reservoir according to the pattern to be run; (viii) spool up fibers on a yarn head and turn on heater; if pre-coated fibers are used, preheat for 15-30 minutes depending on quantity of yarn and spools; (ix) run Zero and home routines on the gantry to establish a baseline position; correct as required to obtain a repeatable position within +/−0.5 mm, and select the fiber trajectory plot file and execute; (x) as fibers are placed, be sure end points are constrained during head rotation, and cut fiber after securing to minimize excessive fiber usage; (xi) observe the head and remove any excessive adhesive build up prior to it passing onto the film with the fiber (creating a gel spot); (xii) when fibers are placed, place top film on buildup in proper X-Y position; touch in the geometric center and press to the outer edges in ever increasing circular/elliptical motions with a cotton gloved hand or press down on short axis continuous line with a release covered roll, then roll to each end in one continuous motion while maintaining a slight tension of the film at the tip and keeping it slightly elevated with respect to the surface of the table; (xiii) if any air pockets are noted, they should be worked out (by gloved hand); (xiv) place an air breather and vacuum bag sealant tape around gore(s), providing sufficient airway for good vacuum; (xv) cover the entire setup with top vacuum release film, seal edges with brayer and eliminate all wrinkle gaps; (xvi) install vacuum connection fitting and gauge fitting; install vacuum gauge, connect the vacuum pump and start; pull down to around 24″ Hg minimum; (xvii) change yarn head for IR heater use (placed on the gantry); start the heater, warming up to operating temperature; (xviii) select an appropriate cure program and execute, monitoring surface temperature with a temperature sensor (record data midway through each pass; if insufficient temperature is reached to initiate, the cure pattern may be run again if using thermoplastic adhesive; if not, thermoplastic and kickoff temperature may not be continuous and the part will likely need to be scrapped); (xix) after the cure process, remove vacuum and fittings, release layer, and air breather material; (xx) lift the gore from the table, being careful to leave edge release strips intact; place the gore on an auxiliary flat surface between two layers of release film; place weight bags or the like around the perimeter to minimize exposure to moisture.
[0044] When fabricating a gore offset joint, particularly where the gore edges are compound surfaces using three-dimensional arch fixtures, some of the useful fabrication practices include: (i) select a first gore to be joined, removing the release edge strip; (ii) start a vacuum on the arch and close off the bypass valve completely; (iii) place the edge of film along a centerline to the arch; fibers should be on the up side away from arch surface; (iv) select a second gore to be joined, removing the release edge strip; (v) place the gore on arch, with the edge on a centerline with its edge fiber facing down toward the other gore's upward facing edge fibers; (vi) verify alignment of cross over fibers; correct any fibers that are not within a predetermined position (e.g., 1 cm) of each opposing fibers in the pattern of the other gore; (vii) adjust a bypass valve as required to maintain a predetermined (e.g., 24″ water) vacuum; (viii) cover the joint with a release film that is long enough to reach the lower ends of the arch (in order to be held with the vacuum); (ix) install the Joint IR heater head on the gantry; (x) verify the heat shield is available for start and end of pass(es); (xi) select a suitable cure program and execute; (xii) use a heat shield as needed to protect the joint from overheating at start and end of the pass; (xiii) open a bypass valve, remove the release film; (xiv) rotate the sealed gores into a cradle under the arch; position a next edge as in step (i) above; (xv) select a next gore and repeat steps (i) through (xiv) until the complete deployable is formed (and in the case of inflatables, attach load/deployment system and seal the ends).
[0045] Of course, one skilled in the art will appreciate how a variety of alternatives are possible for the individual elements, and their arrangement, described above, while still falling within the spirit of our invention. Further, while the above describes several embodiments of the invention used primarily in connection with inflatables, those skilled in the art will appreciate that there are a number of alternatives, based on deployable systems design choices, and choice of materials, and the like that still fall within the spirit of our invention. Thus, it is to be understood that the invention is not limited to the embodiments described above, and that in light of the present disclosure, various other embodiments should be apparent to persons skilled in the art. Accordingly, it is intended that the invention not be limited to the specific illustrative embodiments. | An illustrative embodiment of the invention includes an apparatus and method for making air and space inflatables and deployables using three dimensionally reinforced (3DR) membranes. A 3DR process preferably takes plural substantially flat gore segments, each segment made of plural membranes and reinforcing fibers, and joins adjacent gores so the seams on opposite sides are offset. Single ply seam tape may be used. When all gores are joined, a three dimensional deployable or inflatable (e.g., balloon) structure with a minimized seam is produced. Further, localized fiber reinforcement may be used, with different characteristics depending on the desired placement in the gore, allowing the substantially flat gores, when joined and loaded, to strain to the desired three dimensional shape. In doing so, the required number of gores and seams may be reduced, while using materials with significantly lower areal densities. Thus, the 3DR process allows one to make locally reinforced materials that optimize strength to weight ratios; permits single ply and sub-gore width seam tapes; permits multi-phase optimized envelope shapes, designed to efficiently handle multiple loading conditions; and provides increased design flexibility for a wide range of shapes and characteristics impractical or unavailable under prior techniques. | 1 |
TECHNICAL FIELD
This application involves methods, technologies and applications of wireless devices and network communication system.
BACKGROUND
Conventional video surveillance systems are usually pre-installed and therefore static. Their weakness includes fixed coverage scope and easy to get around. Point to Point based mobile surveillance system and applications have been proposed to complement it. However, their merits suffer from network delay, bandwidth limit among other issues. As mobile phones and other mobile communication devices are becoming more and more popular, being able to collect, process and transmit a rich variety of data such as video, image, GPS among others, with powerful host computation and sensing resources running all kinds of applications, they are applicable yet to provide us a new utility as a personal security guard by working as a mobile surveillance terminal. Off the shelf mobile phones and state of art wireless communication systems have some deficiencies to accomplish this task. Firstly, off the shelf mobile phones are usually not optimized for surveillance operations, and a dedicated optimized design and related service routines are required; Secondly, the time for a mobile communication device to connect to a wireless node in the service area could be delayed due to things like channel congestion and bandwidth limit by state of the art communication methods; Thirdly, the time for the data transmission through the network could also be delayed for similar reasons; Finally, in an extreme case, the person in possession of the device may be in a bad situation not to be able to send an alarm, or the device is damaged or robbed by an offender even before the alarm and related scene information are sent out.
SUMMARY OF THE INVENTION
The intent is to introduce a Point to Node based wireless communication method to build a faster and more reliable real time mobile surveillance network communication system, comprising the following three major components: 1. A mobile phone or other types of mobile communication devices with properly designed features capable of monitoring and analyzing the scene and in emergency situation collecting, processing and sending the data and alarm promptly via the available wireless network. 2. A wireless networking node and system capable of emergency handling mechanisms such as prioritized connecting, transmission and temporary data buffering and storage. 3. A third party surveillance service provider or public security surveillance center at the back end capable of monitoring and processing incoming alarms and data, and responding promptly. The merits of such as a system is faster response to emergencies and faster and more secured acquisition of scene evidences. The advantage of Point to Node over the Point to Point method is such that for the former, transmission could start as soon as the Point Device and the Node are ready, while for the latter, both Points at two ends and wireless network in between need to be ready. Another advantage is for the former, the data transfer bandwidth is more or less only limited by the channel bandwidth between the sending Point and the Serving Node, due to the emergency data could be more or less of a burst nature to start, and temporary data buffering within the wireless node and network could help, even if down streaming has bottle necks.
BRIEF DISCUSSION OF THE DRAWING
FIG. 1 Illustration of the system structure and its operation mechanism
FIG. 2 and FIG. 3 a preferred embodiment of a hidden surveillance panorama camera built into the mobile phone
FIG. 4 is an example set up for a surveillance mobile phone application
DETAILED DESCRIPTION
Nomenclature
SG: security guard.
SGP: A security guard mobile telephone or mobile communication device.
Operator: In some mobile phone designs and usage, only the owner as an administrator has the privilege to use all functionalities of the device, though the owner may allow someone else to use the phone as an option. To simplify the description, it is assumed the actual operator of SGP is either the owner or an authorized user, having the same privileges to access the full functions of the SGP and is named operator hereafter in this disclosure.
A point to node wireless network surveillance communication system, as illustrated in FIG. 1 , comprises a wireless communication node 20 and a SGP device 10 , and the former has prioritized communication protocols including prioritized connection between the node and the device, prioritized routing scheme, including prioritized connection to the SGP device 10 and destination devices and temporary emergency data buffering by the node of the received data from the device, while the latter has an ordinary state and SG state, and the SG state further comprises an Alert Step and an Alarm Step. A SGP could be switched from an ordinary state to SG state by an operator pushing an Alarm Button or ether another interactive method, and when it enters into Alarm Step, the SGP activates SG service routines fast collecting, processing and packaging selectively data such as video, image, GPS, thermostats, gyro sensor, lux meter etc., and uploads the data packets via prioritized data service communication protocols to the wireless networking node, which prioritizes by module 40 the routing of the data packets and at the same time store the data packets in an temporary emergency data buffer 30 , wherein storing the data packets in the temporary emergency buffer 30 has a higher priority than routing the data packets if the speed of routing the data packets is slower than storing the data packets in the temporary emergency buffer 30 .
The uploaded data packets comprises a header section and a data section, and the header comprises the phone number of the SGP, the Emergency Level Code and network destination addresses. The communication protocol between the wireless network and the SGP supports and interprets the header format and the wireless network supports the prioritized data transmissions and concurrent temporary data buffering.
Besides the operator switching method, the SG Alarm Step could also be triggered by certain preset conditions, and when met, the SGP activates Alarm service automatically. The activation could also be remotely controlled by an operator, a Third Party Surveillance Provider, or a Public Security Surveillance Center.
Further, the loud speaker of the SGP could be remotely controlled and used to send warning-off message if necessary.
Further, the data uploaded could be captured real time data or pre-acquired history data.
Further, the Alert Step can run in background in the ordinary state, conducting automatic scene analysis, system resource budgeting, wireless network connecting, data collecting, processing and other initialization services. The Alarm Step will be automatically triggered once preset conditions are met.
Further, some selective Alert Step procedures could keep working even when the ordinary services of the SGP is powered off, to provide around the clock protection.
Further, the lux meter on the SGP can switch the camera operation between ordinary illumination and infrared illumination.
Further, a preferred embodiment of a hidden surveillance panorama camera apparatus built into the a corner of the mobile phone to enhance its video surveillance capabilities as illustrated by FIG. 2 and FIG. 3 , wherein the panoramic camera operates as an usual fixed view angle camera when under a convertible mechanical cover, and once the cover is removed as in security guard mode, the panoramic camera makes up to three dimensional rotations and translations to acquire panoramic images or videos. The panorama camera apparatus could also be used in non-surveillance mode of the device.
Further, SGPs has have prioritized voice channel connection and usage.
Further, the mobile phone needs to be registered with and granted SGP privilege by the wireless network communication service provider prior to its actual usage, the Emergency Level Code and destination network addresses could be set as default at registration and changed later by an operator, an operator authorized Third Party Surveillance Provider or Public Security Surveillance Center.
Further, the emergency data buffer of the wireless network could reside in a node resource area or its extended network storage area.
Further, the wireless networking node comprises mobile network stations and WIFI AP nodes.
The above described method and system is realized in the following steps:
A mobile communication device acquires the security guard priority communication privilege via a registration process with a security guard wireless network communication service provider; the wireless service provider stores the registered device identification number, Emergency Level Code and destination network addresses of the mobile communication device in the service provider's network prioritized emergency service data base.
The wireless networking node of the service provider checks when receiving a connection request, the identification number of the requesting device to verify if the identification number belongs to a registered security guard mobile-communication device, and if it does, the prioritized communication is granted.
The wireless networking node of wireless network communication service provider acknowledges the connection request from the registered security guard mobile communication device and at the same time initializes prioritized communication process of the wireless networking node and its wireless network, comprising allocation of channel bandwidth and temporary emergency buffer space as well as locating proper back end services available in nearby area of the wireless networking node and the registered security guard mobile communication device.
The registered security guard mobile communication device enters into Alert Step, running procedures to allocate system resources, connect to the wireless networking node, and conduct data collection, processing and scene analysis, and when Alarm Step is triggered, selectively packs the data into data packets and uploaded the data packets to the network via the wireless networking node; The destination addresses and Emergency Level Code within the header section of data packets could be updated.
The wireless networking node prioritizes the routing of uploaded data packets to the destination addresses according to the priorities defined in Emergency Level Code, and store the uploaded data packets to temporary emergency buffer of the wireless networking node concurrently; wherein, if the Emergency Level Code in the data packets indicates a Third Party Surveillance Provider or a Public Security Surveillance Center to be a destination, the wireless networking node checks if the service of the Third Party Surveillance Provider or the Public Security Surveillance Center is available in the serving area of the wireless networking node, and if not, the wireless networking node has the option to route the data packets to applicable Public Security Surveillance Centers as the highest priority.
The networked devices comprising the destinations devices 50 receiving the data packets from the registered security guard mobile communication device have the privilege to remotely control operations of the sending security guard mobile communication device.
An example of the Emergency Level Code organization is illustrated in the below table 1
0
Ordinary State
1
SG State with Private Addresses (PA)
2
SG State with Third Party Surveillance Providers (TPSP)
3
SG State with Public Security Surveillance Centers (PSSC) −>
mobile 911
4
SG State with PA + PSSC
5
SG State with TPSP + PSSC
6
SG State with PA + TPSP + PSSC
Some application scenarios are as follows. One person is traveling and staying in a hotel suit, who does not expect any visitors or room services when in sleep. The first SGP is set up in Alert Step and the Emergency Level Code at 6, the destination addresses include the person's second SGP nearby the bed. The camera head points to the doorway or the windows, and video surveillance service is on while voice service is off. If there is an intruder trying to enter or entered the room, an alarm signal would wake the person up and the captured image will show up on the screen of the second SGP, which would give the person some time to react. At the same time, the alarm and the captured images are stored in the network and sent to the hotel's security service center and public surveillance center, before the intruder could locate the SGP and damage it. The little time gained by the SGP probably may save the person's life, and the securely stored data could be a valuable evidence in the case.
Using the loudspeaker on the SGP to warn off the intruder could be another interesting application. A robber sneaks into a house trying to find something, who is welcomed by a voice from the SGP:” welcome to this house, your picture has been taken and sent to police”. In this and similar scenarios, SGP could not only work as a passive reporter but also an active defender.
Other scenarios including in accidents such as crash, fire, or medical emergencies, where the SGP could trigger the alarms, before the operator could do something or anything.
Finally, although the above description is focused on SGP as a preferred application, the disclosed method and system applies in general to other mobile communication devices as well, if they acquire the SG priority communication privilege and have the SG capabilities. | Disclosed are methods for a point to node based surveillance applicable prioritized wireless communication system comprising one or more wireless communication devices and one or more wireless networking nodes using a prioritized wireless communication method, capable of faster response to emergencies and faster and more secured acquisition of real time scene evidences. | 7 |
FIELD OF THE INVENTION
The present invention relates to a decoding technology, and more particularly, to a method for controlling timing between decoding and displaying of successive B pictures in a video decoder for decoding bitstream, and an apparatus therefor.
BACKGROUND OF THE INVENTION
An MPEG(moving picture experts group)-2 video includes three picture types: an intra-coded (I) picture, a bidirectionally-coded (B) picture and a predictive-coded (P) picture. The MPEG-2 video is coded in frame picture units or field picture units. The I picture can be decoded regardless of other pictures, the P picture can be decoded from a previous I or P (I/P) picture, and the B picture can be decoded from previous I/P pictures and subsequent I/P pictures.
When the I, B and P pictures are all included in input pictures, the sequence of decoding differs from that of displaying. Accordingly, timing between decoding and displaying of the input pictures must be properly controlled to restore the original picture. Therefore, the video decoder must include frame memories for decoding the I or P pictures. Further, a memory must be provided wherein the previous and subsequent I/P frames for B picture decoding are stored.
When the B picture is a frame picture that must be displayed in field units, the B picture should be displayed after at least one field is stored. However, when the B picture is stored by only one field, one frame must be decoded while displaying one field. As a result, decoding time distribution is not efficient.
In addition, where one frame of the B picture is decoded and stored, and the size of a memory for B picture storage is set as two frames to store one following frame of the B picture during displaying the stored B picture of one frame, the timing between decoding and displaying is easily controlled, but hardware burden is increased.
Since the maximum frame size of an MPEG-2 main profile high level is about 27 Mbit, it is economical to set the memory space for B picture storage as one frame. However, when the B picture is stored only by one frame and the B picture is a frame picture which should be displayed in field units, the control of timing between decoding and displaying of successive B pictures becomes complicated.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method for setting the size of a memory, required for decoding and displaying of a B picture, as one frame, and providing a control to prevent the overlap of decoded data of successive B pictures with displayed data thereof.
It is another object of the present invention to provide an apparatus for setting the size of a memory, required for decoding and displaying of a B picture, as one frame, and making easy control to prevent the overlap of decoded data of successive B pictures with displayed data thereof.
To accomplish the first object, there is provided a method for controlling the timing between video decoding and video displaying in a video decoder including a memory for storing decoded bidirectionally-coded (B) picture data. The method comprises the steps of: (a) decoding a first B picture, included in an input video bitstream, on the basis of previous and following intra-coded (I) and predictive-coded (P) pictures, and storing one frame of decoded first B picture data in the memory; displaying the decoded first B picture data stored in the memory and decoding a subsequent B picture; and (c) comparing the amount of data displayed with the amount of data decoded while the decoded first B picture is output from the memory for display, to control decoding of the subsequent B picture to prevent the decoding from overlapping with the displaying.
To accomplish the second object, a video decoder in an apparatus for controlling the timing between video decoding and video displaying, decodes a B picture included in an input video bitstream, on the basis of previous and following I and P pictures. A memory stores the decoded B picture by one frame. A decoding controller compares the displaying degree with the decoding degree while outputting the decoded B picture stored in the memory, and controls decoding of the B picture to prevent the decoding from overlapping with the displaying.
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects and advantages of the present invention will become more apparent by describing in detail a preferred embodiment thereof with reference to the attached drawings in which:
FIG. 1 is a block diagram of an apparatus for controlling timing between video decoding and displaying, according to the present invention;
FIG. 2A is an input timing view of an encoder to facilitate understanding of the present invention, FIG. 2B is a timing view of the output of an encoder and the input of a decoder, and FIG. 2C is an output timing view of the decoder;
FIGS. 3A through 3F are output timing views of the control apparatus of FIG. 1 in case that the top field first signal is "1";
FIGS. 4A through 4F are output timing views of the control apparatus of FIG. 1 in case that the top field first signal is "0";
FIG. 5 is a detailed block diagram of the decoding controller shown in FIG. 1; and
FIGS. 6A through 6D are timing views of the input and output signals of the decoding controller shown in FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, an MPEG-2 video decoder 110 decodes video data from an input video bitstream, detects a picture type signal, a slice vertical position signal and a top field first signal which are included in the video bitstream, and provides the detected picture type signal and the detected slice vertical position signal to a decoding controller 130. When the picture type signal included in the input bitstream is a B picture, the MPEG-2 video decoder 110 simultaneously decodes the video data and outputs the video data to be displayed on the basis of the top field first signal in synchronization with a field discriminating signal and a horizontal synchronous signal which are received from an external source. At this time, when a frame memory 120 setting a space for storing B pictures as one frame is used, the decoding of the B pictures overlaps with the displaying of the B pictures. That is, when the amount of data displayed (degree of displaying) precedes the amount of data decoded (degree of decoding), the decoding controller 130 generates a decoding stop signal to stop the decoding performed by the MPEG-2 video decoder 110. In this manner, the decoding is prevented from overlapping the displaying.
When the picture type signal included in the input bitstream is an I picture, the MPEG-2 video decoder 110 decodes the I picture, stores the decoded I picture data in the frame memory 120, and outputs previously stored I picture data for displaying in accordance with the top field first signal in synchronization with the field discriminating signal and the horizontal synchronous signal. When the picture type signal is a P picture, the MPEG-2 video decoder 110 decodes the P picture, stores the decoded P picture data in the frame memory 120, and outputs previously stored P picture data for displaying in accordance with the top field first signal in synchronization with the field discriminating signal and the horizontal synchronous signal, thereby outputting the original sequence which has not been subjected to an encoding process. At this time, frame memory areas for the I and P pictures, as well as a one-frame memory area for the B picture, are allocated in the frame memory 120.
Here, when the B picture, as well as the I and P pictures, are included in the input bitstream, the sequence of decoding is different from that of displaying. Therefore, displaying should not be performed in the same sequence as that of decoding. That is, when the input sequence of an MPEG-2 video encoder (not shown) on a transmission side follows I1, B2, B3, P4, B5, B6, P7, B8, B9, P10, B11, B12, P13, . . . , as shown in FIG. 2A, the sequence of the output of the MPEG-2 video encoder and at the same time the input of the MPEG-2 video decoder 110 follow I1, P4, B2, B3, P7, B5, B6, P10, B8, B9, P13, . . . , as shown in FIG. 2B, and the sequence of the output of the MPEG-2 video decoder 110 is the same as that of the input of the MPEG-2 encoder such as I1, B2, B3, P4, B5, B6, P7, B8, B9, P10, . . . , as shown in FIG. 2C.
However, when only one frame is used as the size for storing the B pictures, the decoding and displaying of the B picture are overlapped as shown in FIGS. 3A through 4F. That is, the MPEG-2 video decoder 110 starts decoding an input picture which is a frame picture in a bottom field when the top field first signal included in the MPEG-2 video bitstream is "1." On the other hand, the MPEG-2 video decoder 110 starts decoding the input picture in a top field when the top field first signal is "0." A corresponding field is output to be displayed according to the externally input field discriminating signal, as shown in FIG. 3A.
Here, the top field first signal is information representing the sequence of the output field of a frame picture. When it is "1," the top field must be output in advance, and when it is "0," the bottom field must be output in advance. The top field is a field including every odd numbered lines such as a first line, a third line, . . . , of a frame, and the bottom field is a field including every even numbered lines such as a second line, a fourth line, . . . The field discriminating signal shown in FIG. 3A is an input signal provided by an external source to the MPEG-2 video decoder 110, and determines whether the output field is a top field or a bottom field. That is, when the field discriminating signal is "0," the output field is the top field, and when the field discriminating signal is "1," the output field is the bottom field.
Accordingly, when the top field first signal detected by the MPEG-2 video decoder 110 is "1," the period for decoding a picture is as shown in FIG. 3B, and, during the period for displaying a picture, the top field is decoded and output in advance as shown in FIG. 3C. When a picture currently being decoded is an I/P picture, the previous I/P picture is displayed. On the other hand, during the time when the B picture is being decoded, the B picture being decoded is displayed. Here, the sequences of picture decoding and picture displaying respectively shown in FIGS. 3B and 3C represent parts of those of picture decoding and picture displaying shown in FIGS. 2B and 2C. Also, "b" and "t" shown in FIG. 3C denote a bottom field and a top field, respectively.
Meanwhile, the period for B picture decoding is as shown in FIG. 3D, and the decoded B picture is displayed as shown in FIG. 3E. However, when a picture currently being decoded is a B picture, and when a previous decoded picture is also a B picture, the period for displaying a second field of the previous decoded B picture overlaps with that for decoding a current B picture, as shown in FIG. 3F.
During this overlapped period, the degree of decoding of a current picture is compared with that of displaying of a previously decoded picture in slice units. Then, previously decoded data is output, and current decoded data is then stored in the frame memory 120. The slice, being a coding unit of a lower-ranking than the picture, constitutes a picture and is a 16-line unit.
When the top field first signal included in the input bitstream is "0", timing views, where the bottom field is decoded and displayed in advance, are shown in FIGS. 4A through 4F. FIG. 4A represents a field discriminating signal, FIG. 4B represents a picture decoding period, FIG. 4C denotes a picture displaying period, FIG. 4D shows a B picture decoding period, FIG. 4E shows a B picture displaying period, and FIG. 4F shows a B picture overlapping period.
FIG. 5 is a detailed block diagram of the decoding controller 130 shown in FIG. 1. When a slice vertical position signal, in one picture, representing the degree of decoding is greater than or equal to a display slice signal representing the degree of displaying, during the period when the decoding of the B picture is overlapped with the displaying thereof, a decoding stop signal is generated to stop decoding of the MPEG-2 video decoder 110. Thus, the overlap of the decoding with the displaying is prevented.
The operation of the decoding controller 130 shown in FIG. 5 will be described with reference to the timing view of FIGS. 6A through 6D. That is, the slice vertical position signal shown in FIG. 6A is included in the video bitstream, and input to a first input "a" of a comparator 153. A display slice counter 151 counts an input horizontal synchronous signal, and outputs the display slice signal, as shown in FIG. 6B, whose count value increases with every eight signals. Also, the display slice counter 151 is reset whenever the logic of the field discriminating signal is changed. Here, the display slice counter 151 counts 8 horizontal synchronous signals because a slice of a frame picture has 16 lines and the 16 lines are separated into 8 lines in every field.
An overlapped period determiner 152 makes an overlapped period signal shown in FIG. 6C into "1" to indicate the start of the overlapping period, when a picture to be decoded is a B picture and its previous picture is also a B picture. In this case, the overlapped period determiner 152 also sets the overlapped period signal as "0" at the time when the field discriminating signal is changed, to indicate the end of the overlapped period. Here, the picture type signal is two-bit data included in the video bitstream. When the picture type signal is expressed as "01," the picture is an I picture. When the picture type signal is expressed as "10," the picture is a P picture. Also, when the picture type signal is expressed as "11," the picture is a B picture.
The comparator 153 compares the slice vertical position signal, as shown in FIG. 6A, with the slice signal output by the display slice counter 151, as shown in FIG. 6B. When the vertical position signal is greater than or equal to the display slice signal, the comparator 153 generates a logic "1" output signal. Accordingly, a decoding stop signal generator comprising an AND gate 154, performs an AND operation on the output signal of the comparator 153 and the overlapped period signal of logic "1", shown in FIG. 6C, provided by the overlapped period determiner 152. Then, the decoding stop signal generator generates a decoding stop signal of the logic "1" shown in FIG. 6D. The MPEG-2 video decoder 110 stops decoding when the decoding stop signal is "1", and stands by until the decoding stop signal returns to "0".
The embodiment of the present invention had been applied to the case when a frame picture is decoded and displayed in field units. However, the embodiment can be also applied to the case when a frame picture is decoded and displayed in frame units.
In the case of decoding and displaying a B picture, if the memory space for B picture storage is set as one field, a decoding efficiency is lowered. When the memory space is set as two frames, it raises a problem that the capacity of the memory should increase. To solve the above defects, the present invention sets the memory space for B picture storage as one frame, and simultaneously prevents picture decoding from overlapping with the picture displaying. Thus, the decoding efficiency is not degraded even though a memory of two-frame size is not employed. | A method and apparatus are provided for controlling the timing between video decoding and video displaying. The apparatus contains a video decoder for decoding a B picture included in an input video bitstream, on the basis of previous and following I and P pictures, a memory for storing the decoded B picture by one frame, and a decoding controller for comparing the amount of data displayed with the amount of data decoded while outputting the decoded B picture stored in the memory, and controlling decoding of a subsequent B picture to prevent the decoding from overlapping with the displaying. In the apparatus, although the memory space for B picture storage is set as one frame, the decoding of a picture is prevented from overlapping with the displaying thereof. Thus, decoding efficiency is not lessened even though a memory of two frame size is not employed. | 7 |
BACKGROUND OF THE INVENTION
This invention relates generally to slide clamps used to control fluid flow through an IV line. More specifically, the present invention relates to an apparatus which requires structural cooperation between the slide clamp and an IV infusion medical device for activation and deactivation of the clamp on the IV line. The present invention is particularly, though not exclusively, useful for the operative engagement and subsequent safe disengagement between an IV line and a linear peristaltic IV infusion pump.
DESCRIPTION OF THE PRIOR ART
The use of medical devices for the IV infusion of medical solutions to patients is well known in the medical professions. One type of medical device which has been widely used for this purpose is the peristaltic pump. As is well known in the pertinent art, peristaltic pumps create a moving zone of occlusion along a portion of the IV line to create the pumping action required. However, because they require a patent IV tube for their operation, when the tube is not engaged with the pump, there is the danger of possible unwanted free flow of medical solution from the fluid source directly into the patient. Typically, the times of greatest concern for this danger are during the initial set-up of the IV administration system and at any subsequent times when the IV line is connected between the fluid source and the patient and becomes, for whatever reason, disengaged from the device.
The control of fluid flow through patent IV lines from a fluid source to a patient is an ever present problem and several devices to help solve this problem have been proposed. For example, slide clamps which constrict or obstruct the IV line are well known. Typically, these are manually operated clamps which are found in various configurations. One such clamp is a roller clamp of the type described in U.S. Pat. No. 3,189,038 to Von Pechmann. Another type is the well-known slide clamp, an example of which is disclosed in U.S. Pat. No. 2,889,848 to Redmer. Again, such clamps are manually operated. Further, they must be activated independently and separately from any medical device which may be operatively attached to the IV fluid line.
In situations where a medical device is to be used for the infusion of medical solutions to a patient, it is necessary to coordinate the use of a tube clamp with the operation of the device. For reasons given above, this is particularly so where a peristaltic pump is used. The idea of associating the clamp with the device to bring about a cooperation of structure therebetween is known in the prior art. For example, the invention disclosed in pending application Ser. No. 733,667 to Kozlow, now U.S. Pat. No. 4,586,691, which is assigned to the assignee of the present invention, discloses a safety slide clamp which requires the cooperation of structure between the device and the clamp itself. Such a clamp as disclosed in the Kozlow application, however, requires manual activation of the clamp to open the tube prior to the actual operation of the pump. Although such a clamp may be acceptable in some cases, in others the additional manipulation required to activate the clamp may be inconvenient or undesirable.
In light of the above, it can be appreciated that there is a need to simplify the engagement of an IV tube with a peristaltic infusion device. Specifically, there is a need to reduce the number of steps necessary to accomplish such an engagement. Thus, there is a need for a clamping apparatus which eliminates the manual step of activating the tube clamp.
Accordingly, it is an object of the present invention to provide a clamp activation apparatus which ensures safe operation of a peristaltic infusion device. It is another object of the present invention to provide a means which ensures that only a restricted or obstructed IV tube can be engaged with a peristaltic device. Further, it is an object of this invention to provide a device which prevents removal of a patent tube from the device. It is yet another object of the present invention to provide an apparatus which automatically makes the tube patent while simultaneously preparing the device for its operation.
SUMMARY OF THE INVENTION
The activation apparatus of the present invention provides for the activation of an IV tube associated slide clamp through the operation of structural components of an IV infusion medical device. The present invention includes means for holding the IV tube in operative engagement with the device while a handle which is pivotally mounted on the device is allowed to move into engagement with the clamp. The handle is structured to urge the clamp from a closed position, wherein the clamp constricts or restricts the flow of fluid through the tube, to an open position wherein the tube is patent. The handle also includes structure to operate reversibly and urge the clamp from the open position to the closed position in preparation for the removal of the tube from the device. The apparatus of the present invention also comprises a lockout means which is mounted on the device to ensure that initial engagement of the IV tube with the device can only be accomplished when the clamp is in the closed position.
The novel features of this invention as well as the invention itself, both as to its organization and operation, will be best understood from the accompanying drawings taken in conjunction with the accompanying description in which similar reference characters refer to similar parts and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation view of a peristaltic device incorporating the present invention in operable engagement with an IV tube;
FIG. 2 is an elevation view of an IV tube in engagement with a linear peristaltic pump with various components disengaged from one other;
FIG. 3A is an exploded perspective view of the slide clamp assembly with portions broken away for clarification;
FIG. 3B is a perspective view of the lower hinge bracket of the present invention;
FIG. 4 is a perspective view of the slide clamp assembly nested in the lower hinge bracket with the slide clamp in a tube constricting position;
FIG. 5 is a perspective view of the slide clamp assembly nested in the lower hinge bracket with the slide clamp in a tube open position;
FIG. 6 is a perspective view of the grip of the present invention;
FIG. 7A is an elevation view of the handle and slide clamp assembly in a disengaged configuration with portions of structure omitted for clarity;
FIG. 7B is a view of the handle and slide clamp assembly as shown in FIG. 7A in a partially engaged configuration with portions of structure omitted for clarity;
FIG. 7C is a view of the handle and slide clamp assembly as shown in FIG. 7A engaged with the slide clamp closed on the IV tube with portions of structure omitted for clarity; and
FIG. 7D is a view of the handle and slide clamp assembly as shown in FIG. 7A engaged with the slide clamp positioned for an open IV tube with portions of structure omitted for clarity.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The intended environment for the present invention is best seen in FIG. 1 where a peristaltic infusion device, generally designated 10, is shown in operative engagement with an IV tube 12. In FIG. 1, it is seen that a fluid source 14 can be suspended from appropriate apparatus associated with an IV pole 16 and IV tube 12 connected for fluid communication between fluid source 14 with a patient (not shown).
Referring now to FIG. 2, it is seen that IV tube 12 includes a pumping section 18 made from any appropriate elastomeric material which will permit an effective peristaltic action on the pumping section 18. One end of pumping section 18 is connected into fluid communication with IV tube 12 by a fitment 22. A slide clamp fitment 20 connects the other end of pumping section 18 with a continuation of IV tube 12. With therse connections, a continuous fluid path is provided through IV tube 12 and its associated pumping section 18.
As shown in FIG. 2, IV tube 12 and its associated pumping section 18 are mounted on the device 10 by the engagement of fitment 22 with upper bracket 26 and the engagement of slide clamp fitment 20 with lower hinge bracket 24. Thus, when IV tube 12 is engaged with device 10, pumping section 18 is positioned against the peristaltic pumping means 28. Also, with this engagement, pumping section 18 is placed under slight tension to ensure a snug fit between pumping section 18 and the peristaltic device 10. The connection of fitment 22 between IV tube 12 and pumping section 18 can be accomplished by any means well known in the art, such as solvent bonding. Likewise, the connection between slide clamp fitment 20 and pumping section 18 and IV tube 12 can be accomplished by any means well known in the pertinent art.
FIG. 3A shows an exploded perspective view of the slide clamp assembly for the present invention, generally designated 30. As shown, slide clamp assembly 30 includes slide clamp fitment 20 which is formed with a tab 34 and a tab 36. Further, tab 36 is formed with a key 38. Slide clamp fitment 20 is also formed with guides 40a and 40b and with retaining snaps 42a, b, c and d. The retaining snaps 42a, b, c and d allow for a snap fit engagement of the slide clamp 32 with slide clamp fitment 20 into a structure which is best seen in FIGS. 4 and 5. Further, the engagement of slide clamp 32 with slide clamp fitment 20, which permits the sliding of clamp 32 relative to fitment 20, is restrained by the mating engagement of ridges 44 with guides 40a and 40b. Although not shown specifically in FIG. 3A, it can be appreciated that ridges 44 are formed around the periphery of slide clamp 32 simply by forming a depression on the surface of slide clamp 32 (depression not shown in FIG. 3A).
In light of the foregoing, and since IV tube 12 is fixedly attached to slide clamp fitment 20, the engagement of slide clamp 32 with slide clamp fitment 20 allows for reciprocal motion of the slide clamp 32 relative to IV tube 12. Accordingly, this motion will cause either a patent IV tube 12 or a restricted IV tube 12. More specifically, by positioning clamp 32 relative to IV tube 12 so that IV tube 12 is in the enlarged portion 48 of aperture 46, a patent IV tube 12 is obtained. Subsequently, IV tube 12 can be restricted by moving slide clamp 32 relative to IV tube 12 so as to position IV tube 12 within the slotted portion 50 of aperture 46 when it is desired to restrict or occlude IV tube 12. Reference to FIG. 4 and FIG. 5 shows the positioning of slide clamp 32 relative to IV tube 12 and its respective positioning relative to slide clamp fitment 20 when the slide clamp 32 occludes IV tube 12 and when slide clamp 32 allows fluid flow through IV tube 12.
As shown in FIG. 2, lower hinge braket 24 is mounted to the front of the device 10. A more detailed description of lower hinge bracket 24 and its structure for the present invention is, however, best appreciated with reference to FIG. 3B. As shown in FIG. 3B, the lower hinge bracket 24 is formed with a yoke 52. Also formed on lower hinge bracket 24 is a recess 54 adapted for mating engagement with key 38 of slide clamp fitment 20. Additionally, lower hinge bracket 24 is formed with a platform 56 and a platform 58 which are adapted to respectively urge against tab 34 and tab 36 of slide clamp fitment 20. Also shown in FIG. 3B is sear 60 which is formed on lower hinge bracket 24.
The cooperation of structure between slide clamp assembly 30 and lower hinge bracket 24 is shown by the combination of these components in FIG. 4 or FIG. 5. In cross-referencing FIG. 3B with FIG. 4 or FIG. 5, it will be appreciated that the slide clamp fitment 20 of slide clamp assembly 30 nests in lower hinge bracket 24. It will further be appreciated that the mating engagement of key 38 with recess 54 can only be accomplished upon a specific orientation of slide clamp fitment 20 with respect to lower hinge bracket 24. This requirement for specific orientation of key 38 with recess 54 is a safety feature which prevents an inadvertent mating of slide clamp fitment 20 with lower hinge bracket 24 in an inoperable condition.
Grip 64, which is shown by itself in FIG. 6, includes a pair of hooks 66a and 66b which straddle the channel 74 formed on grip 64. Also formed on grip 64 is a sear cam 68 and a pivot 70. It is to be appreciated that grip 64 is pivotally attached to handle 72 at pivot 70 as shown in FIG. 2. A spring bias (not shown) urges grip 64 in the direction opposite to that indicated by the arrow 78 and into its position relative to door 72 substantially as shown in FIG. 2. Impliedly, grip 64 can be rotated around pivot 70 in the direction indicated by arrow 78 but the spring bias tends to restore grip 64 into the position shown in FIG. 2.
To consider the cooperation of structure between handle 72, its associated grip 64 and slide clamp assembly 30, it should be appreciated that the closure of door 76 onto device 10 places handle 72 relative to slide clamp assembly 30 as shown in FIGS. 7A, 7B, 7C and 7D. These figures need to be considered sequentially. In FIG. 7A it can be appreciated that the handle 72 is rotatably attached to door 76 (not shown in FIG. 7A) at a pivot point 82. Rotation of handle 72 about pivot 82 in the direction of arrow 80 brings both handle 72 and grip 64 into initial contact with slide clamp 32 as shown in FIG. 7B. The comparision of FIG. 7B with FIG. 7A shows that when in the position shown in FIG. 7B, hooks 66a and 66b of grip 64 make contact with projections 62a and 62b of slide clamp 32 and are urged to rotate grip 64 about pivot 70 in the direction shown by arrow 78 in FIG. 2. Further, and more specifically, movement of handle 72 from its position in FIG. 7A to FIG. 7B causes handle 72 to contact end portion 84 of slide clamp 32. A slightly further rotation of handle 72 in the direction of arrow 80 about pivot point 82 causes hooks 66a and 66b to engage with projections 62a and 62b as shown in FIG. 7C. Specifically, cross-referencing FIG. 7B with FIG. 7C shows that the movement of handle 72 into its position as shown in FIG. 7C causes grip 64 to ride over the projections 62a and 62b of slide clamp 32 and allow the spring biased grip 64 to move into its position as shown in FIG. 7C.
The relation of slide clamp 32 to slide clamp assembly 30, as shown in FIG. 7C, corresponds to the configuration of slide clamp assembly 30 as shown in FIG. 4. Thus, as seen in FIG. 7C, IV tube 12 is still restricted and complete engagement of the handle 72 with device 10 has not yet been accomplished. Further rotation of handle 72 in the direction of arrow 80 brings handle 72 into position with slide clamp 32 as shown in FIG. 7D.
FIG. 7D shows the locked engagement which results by closing door 76 on device 10. The lock is accomplished by bringing latch extension 86 of handle 72 into position relative to anchor pin 88. As best seen in FIG. 2, anchor pin 88 is fixedly attached to device 10. It can be appreciated that the rotation of handle 72 in the direction of arrow 80, as shown sequentially in FIGS. 7A, 7B, 7C and 7D, wraps latch extension 86 around anchor pin 88 to lock door 76 against the device 10. This locking accomplishes several purposes. Importantly, it positions door 76 against pumping section 18 for the purpose of acting as a platen in the peristaltic action of peristaltic pumping means 28. Additionally, when locked on device 10, door 76 protects the engagement of fitments 20 and 22 with their respective brackets 24 and 26.
An important safety feature of the present invention can be appreciated by cross-referencing FIG. 2 with FIG. 3B. Both FIG. 2 and FIG. 3B show a lockout spring 90. It is to be understood that in its unbiased position, lockout spring 90 is positioned to prevent the movement of slide clamp 32 from the position as shown in FIG. 4 to a position as shown in FIG. 5 when slide clamp assembly 30 is joined to lower hinge bracket 24. However, as door 76 is closed onto device 10, a pin 92 which is attached to door 76 as shown in FIG. 2 makes contact with lockout spring 90 and bends it in the direction of arrow 94 to allow the sliding movement of slide clamp 32 past lockout spring 90. Thus, with lockout spring 90 cleared from the path of slide clamp 32, slide clamp 32 is capable of being moved from a position as shown in FIG. 4 to the position shown in FIG. 5.
It should be appreciated that the disengagement of IV tube 12 from the device 10 can be accomplished by reversal of the steps previously discussed and that the cooperation of structure between grip 64 and slide clamp 32 would be substantially as shown by sequentially considering FIGS. 7D, 7C, 7B and 7A. Further, it should be appreciated that as door 76 is unlocked by the movement of handle 72, slide clamp 32 is repositioned to constrict IV tube 12. Accordingly, the removal of IV tube 12 from device 10 can only be accomplished when IV tube 12 is constricted to prevent fluid flow therethrough.
OPERATION
For its operation the present invention requires that IV tube 12 be engaged with peristaltic device 10. This is accomplished by positioning fitment 22 on IV tube 12 in upper bracket 26. The pumping section 18 of IV tube 12 is then stretched to allow the positioning of slide clamp fitment 20 into lower hinge bracket 24. This placement of IV tube 12 on device 10 places pumping section 18 of IV tube 12 against peristaltic pumping means 28. The initial engagement of slide clamp fitment 20 with lower hinge bracket 24 positions the slide clamp assembly 30 against lower hinge bracket 24 in the manner shown in FIG. 4. Thus, for its initial engagement the slide clamp 32 is positioned relative to IV tube 12 to constrict and prevent fluid flow therethrough. In both FIG. 2 and FIG. 4, it is seen that the key 38 of slide clamp fitment 20 requires that the engagement of slide clamp fitment 20 with lower hinge bracket 24 be accomplished only as shown in FIG. 4. This places tab 34 and tab 36 respectively against the platforms 56 and 58 of lower hinge bracket 24.
With IV tube 12 positioned against device 10, door 76 can be closed onto device 10. This results in a sequence of operations which will be best appreciated by reference to FIGS. 7A, 7B, 7C and 7D. As the door 76 is closed onto device 10, the latch extension 86 of handle 72 is positioned around anchor pin 88. Additionally, the grip 64 comes into contact with projections 62a and 62b of slide clamp 32. Also, handle 72 makes contact with slide clamp 32 against its end portion 84. Movement of handle 72 in a rotational motion about the pivot point 82 in the direction of arrow 80 causes handle 72 to urge against slide clamp 32 and engage hoods 66a and 66b on grip 64 with the projections 62a and 62b on slide clamp 32. Further movement of handle 72 in the direction of arrow 80, as shown in the progression from FIG. 7B to FIG. 7C, causes the grip 64 to engage with slide clamp 32. Additional movement of handle 72 from its position in FIG. 7C to a position in FIG. 7D causes handle 72 to urge against slide clamp 32 and position slide clamp 32 relative to slide clamp assembly 30 in a position as shown in FIG. 5. Accordingly, when handle 72 has been completely engaged with door 76, IV tube 12 is made patent for the passage of fluid therethrough. Simultaneous with the opening of slide clamp 32 on IV tube 12, the closure of door 76 causes pin 92 to contact lockout spring 90 and bend it in a direction indicated by arrow 94 to allow further motion of the handle 72 against slide clamp 32. As lockout spring 90 is moved out of the way to allow for the movement of handle 72, the sequence of engagement discussed above for FIG. 7A through FIG. 7D is accomplished.
A consideration of FIGS. 7A, 7B, 7C and 7D in reverse order discloses the cooperation of structure required for disengagement of the IV tube 12 from device 10. Specifically, as handle 72 is rotated about pivot point 82 in a direction opposite to arrow 80, the grip 64 is withdrawn in a manner which urges the hooks 66a and 66b against projections 62a and 62b to cause movement of slide 32 from a position relative to IV tube 12 as shown in FIG. 5 to a position for slide clamp 32 relative to IV tube 12 as shown in FIG. 4. It is important that once grip 64 is withdrawn to the position as shown in FIG. 7C, the sear cam 68, which is clearly shown on grip 64 in FIG. 6, rides over sear 60, which is shown in FIGS. 4 and 5 as part of the lower hinge bracket 24, to urge grip 64 in the direction of arrow 78. This motion clears the grip 64 from the projections 62a and 62b of slide clamp 32 and allows for further rotation of handle 72. It will be appreciated that the further rotation of handle 72 is continued until latch extension 86 is cleared from its engagement with anchor pin 88, thus, unlocking door 76 from device 10 and allowing the opening of door 76. Once door 76 has been opened, the IV tube 12 can be removed from its fittings with device 10 and used as desired by the operator. It will be apreciated that the action of grip 64 in opening door 76 has caused slide clamp 32 to constrict upon IV tube 12 and prevent fluid flow through IV tube 12 upon the removal of IV tube 12 from the device 10.
While the IV tube activator has herein shown and disclosed in detail is fully capable of obtaining the object and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiment of the invention and that no limitations are intended to the details of construction or design herein shown other than as defined in the appended claims. | An IV tube activator for use with a peristaltic IV infusion pump comprises means that require the closure of a tube associated clamp upon engagement of the IV tube with the pump and upon any subsequent disengagement of the IV tube from the pump. The activator further comprises means which simultaneously move the tube associated clamp to open the IV tube when the pump is being operated. | 8 |
This application is a continuation-in-part of U.S. application Ser. No. 715,663, now Pat. No. 4,659,290, filed Mar. 25, 1985 by Warren Kundert and entitled Fan Speed Controller.
Background of the Invention
The present invention pertains to the air cooling of electronic equipment and more particularly to a system for fan speed control which maintains substantially constant device temperature for varying inlet or ambient temperatures.
While variable speed or thermostatically controlled fans have been proposed heretofore, prior controller designs have not been well suited for cooling electronic equipment. Further, these prior art systems have not, in general, been responsive to the actual needs of an overall or complete system, particularly when such a system is to be installed in an office environment.
One problem which is engendered by the use of cooling fans for electronic equipment used in an office environment is the noise which such fans can generate. This problem is compounded by the tendency of electronic equipment designers to provide cooling for so-called worst case conditions. In other words, the designer will typically include sufficient air flow capacity to deal with the densest system configuration, most heavily loaded on the hottest expected day. The air flow theoretically required for such worst case conditions will typically be much more than that required under typical or nominal conditions and the fans specified to provide such capability will generate excessive and unnecessary noise. It is, however, very important to assure sufficient cooling capacity since electronic systems, particularly those employing solid state components, are subject to various failures upon overheating.
As is understood by those skilled in the semiconductor art, maximum longevity of semiconductor devices can typically be expected if the devices are maintained at a substantially constant temperature. To a considerable extent, various prior art systems and the system described in the above-identified parent application Ser. No. 715,663 achieve these objectives to a degree by providing thermostatically or temperature controlled fans which vary air flow as a function of temperature for the purpose of providing cooling as needed without generating unnecessary noise. In order to take in account the heat generated by the apparatus being cooled, exhaust air temperature is typically monitored and used as the input for a feedback control system.
In accordance with conventional thinking in the control art, such air cooling systems have heretofore typically incorporated relatively high loop gains so that outlet air temperature is maintained as close as possible to a predetermined value, the set point. The present invention, however, recognizes that such tight control of outlet temperature is not the most desirable situation and provides an improved algorithm for maintaining heat producing devices at essentially constant temperature notwithstanding varying inlet or ambient temperatures. In this regard, the present invention is predicated on an understanding that the thermal resistance from junction to air of a typical semiconductor device varies with air velocity.
SUMMARY OF THE INVENTION
Apparatus in accordance with the present invention is adapted for air cooling electronic equipment of the type which incorporates a plurality of heat generating devices, e.g. integrated circuits packaged in DIPs (dual in-line packages). A variable speed fan, preferably driven by a d.c. motor, is provided for driving an air flow through the equipment. A sensor, such as a thermistor, is provided for sensing the temperature of air flow leaving the equipment. Circuit means are provided for variably energizing the fan such that the change in exhaust air temperature over the available range of air flow rates is substantially equal to the change in the temperature rise above air temperature of a typical one of the heat generating elements over that same range of air flow rates. Preferably, the fan motor is energized in a pulsed d.c. mode to prevent stalling at the low end of the range.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram of an improved fan speed controller constructed in accordance with the present invention;
FIG. 2 is a graph representing the control characteristics of the circuit of FIG. 1;
FIG. 3 is a circuit diagram of an alternative embodiment of the controller; and
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, the control circuit illustrated there is adapted for energizing a d.c. powered fan from d.c. supply leads. Such a fan, including a d.c. motor 13, is indicated generally by reference character 15 while positive and negative supply leads are indicated by reference characters 11 and 12 respectively.
While the use of d.c. powered fans for cooling electronic equipment is becoming increasingly prevalent, such d.c. fans have presented problems with respect to variable speed operation desired to reduce noise and maintain constant temperature. In particular, such fans have shown a tendency to stall when operated at low speeds, typically half their maximum or rated speed.
In accordance with one aspect of the present invention, it has been found that typical d.c. powered fans may be operated at speeds down to and below half their rated speed if the fan motor is energized in a pulsed d.c. mode from a full voltage source, rather than operated at a reduced but steady d.c. voltage. It has also been found that a relatively low pulsing frequency, e.g. 40 cycles per second, is necessary to avoid interference or beat effects with the motor's pole passage rate and to avoid the generation of acoustic noise from the motor's winding as would be the case if commonly used pulsing rates were applied, e.g. pulse rates such as those encountered in switching power supplies.
As may be seen from the circuit diagram of FIG. 1, the fan motor 13 is connected across the d.c. supply leads 11 and 12 through a switching mode power transistor Q1 of the field effect type. Transistor Q1 is shunted by a capacitor C1 to protect it from switching voltage transients. As is described in greater detail hereinafter, transistor Q1 is turned on and off by control circuitry which is shown on the right hand portion of the FIG. 1 schematic. The frequency of switching is at about 40 Hertz but the duty cycle, i.e. the proportion of time the transistor Q1 is on rather than off, is varied to effect the level of energization of the motor 13 and, consequently, the speed of the fan 15. A reduced and regulated voltage for the control circuitry is provided by means of a dropping resistor R1 and a zener diode VR1.
The timing of the switching mode of operation is determined by an astable multivibrator employing a pair of PNP transistors Q2 and Q3. The collector circuits of transistors Q2 and Q3 are provided with load resistors R2 and R3 respectively and the collector of each transistor is cross-coupled to the base of the other transistor in the pair by a coupling capacitor, C2 and C3 respectively. The collector of transistor Q2 is connected directly to the gate of the switching transistor Q1 so that transistor Q1 is turned on when transistor Q2 conducts.
As is understood by those skilled in the art, the transistors Q2 and Q3 conduct alternately with the frequency and relative durations of the alternate phases being determined by the rate at which the cross-coupling capacitors are recharged. Recharging of the capacitors C2 and C3 is provided through the collector or load circuits of a pair of NPN transistors Q4 and Q5 which are interconnected in a circuit which may be thought of as a differential amplifier or phase splitter, the emitters of the transistors Q4 and Q5 being connected, through respective resistors R6 and R7 and a common resistor R8, to the negative supply lead. The collectors of transistors Q4 and Q5 are also connected, through respective load resistors R4 and R5, to the positive supply lead. A nominal d.c. potential is provided to the base terminals of transistors Q4 and Q5 by a voltage divider comprising resistors R9 and R10 which essentially halve the supply voltage, this voltage level being filtered by a capacitor C6.
In the absence of external influences, the current flowing in the collector circuits of the transistors Q4 and Q5 will be about equal and thus the astable multivibrator comprising transistors Q2 and Q3 will operate at a duty cycle which is determined by the relative values of the cross-coupling capacitors C2 and C3. These values are selected to cause the fan to be energized at half speed, this being a sharply defined lower end of the control range. As is described in greater detail in the above-identified parent case Ser. No. 715,663, it is highly desirable that the range of control be quite sharply defined with a sharply defined minimum level of energization. In most circumstances, a minimum of about half speed is appropriate.
Transistor Q5, however, is shunted by a similar transistor Q6. The base of transistor Q6 is connected to a voltage divider comprising an air temperature sensing thermistor T1 and a resistor R11. Thermistor T1 is also shunted by a resistor R13 which sets a maximum value of resistance which will appear in that half of the divider. As indicated previously, thermistor T1 is mounted so that it is responsive to the temperature of the air flow being driven through the electronic equipment to be cooled by the fan 15. Air which has passed the typical or representative heat generating elements in the electronic equipment is conveniently referred to herein as "exhaust air" and the thermistor T1 is mounted to sense the temperature of such air. However, it should be understood that the air flow may pass and help cool other heat generating components before actually leaving the equipment enclosure.
As thermistor T1 is heated, its resistance decreases and, once the voltage at the junction J1 reaches the half supply level point, the transistor Q6 is turned on and begins to conduct, shunting the transistor Q5. Accordingly, the phase splitting circuit comprising transistors Q4 and Q5 will be progressively unbalanced, in turn causing transistor Q2 to conduct a greater proportion of the time within the cycle of the astable multivibrator. Correspondingly, the level of energization of the fan will be raised, since transistor Q1 is driven into conduction by conduction through transistor Q2. While the sense of this servo control is in a direction providing a feedback control system tending to reduce the effects of external changes on the temperature of the air sensed by the thermistor T1, the gain of the system is, in accordance with the present invention, carefully controlled to provide a predetermined response.
As will be understood by those skilled in the electronics art, the gain of the system may be selectively adjusted over a quite considerable range by appropriately choosing the values of resistors R6 and R7 in relation to the value of resistor R8.
FIG. 4 illustrates electronic equipment of the type in which the improved fan controller of the present invention is useful. The equipment comprises an enclosure, designated generally by a reference character 31. Mounted within the enclosure 31 is a motherboard 33 into which one or more circuit cards 35 are plugged. As is typical, each circuit card 35 carries a plurality of semiconductor devices mounted in dual in-line packages 37. Cooling air is admitted to the interior of the enclosure 31 through a louver 39 and is drawn through the enclosure past the semiconductor devices 37 by the fan 15. The thermistor sensor T1 is mounted at the fan so as to respond to the temperature of the exhaust air leaving the equipment.
As indicated previously, the feedback control algorithm is, in accordance with the present invention, selected to maintain the temperature of the heat generating devices in the electronic equipment substantially constant, rather than to maintain a constant exhaust air temperature even though that is the actual parameter sensed by the thermistor T1. As also indicated previously, the thermal resistance of typical semiconductor devices changes as a function of air velocity. In this regard, thermal resistance may be taken as the ratio of temperature rise to power dissipation, temperature rise being defined as the difference in temperature from the surrounding air to the semiconductor junction.
Based on information provided by semiconductor manufacturers, the thermal resistance of a typical sixteen lead dual in-line package is 66 degrees centigrade per watt at 200 feet per minute air flow but is only 54 degrees centigrade per watt at 400 feet per minute air flow velocity. Assuming such a package which dissipates 250 milliwatts of electrical power (a quite representative value), the temperature rise at 200 feet per minute is 16.5 degrees centigrade and at 400 feet per minute is 13.5 degrees centigrade. The difference in the temperature rise for this two-to-one change in air velocity is thus three degrees.
The response of the circuit of FIG. 1 is tailored to match and essentially compensate for this three degree temperature rise difference over a two-to-one air flow ratio. FIG. 2 is a curve which represents the response of the system of FIG. 1 assuming that the thermistor T1 and resistor R11 are selected to provide a temperature above which fans run at maximum speed of 45 degrees centigrade, i.e. the upper end of the control range. The control range, i.e. the range over which proportional feedback control is exercised, is the portion of the curve between the points designated A and B. Below point A the fan runs at a steady speed of about half and above point B the fan runs at maximum speed. In the control range, however, which covers a two-to-one speed range as described previously, the difference in exhaust temperature is three degrees, that is, it matches the difference in temperature rise exhibited by a typical semiconductor device over the same range of air speed rates. It should be noted that this value is a difference in temperature rise not a temperature rise itself.
By providing a match between the system response and the change in thermal resistance, it is possible to maintain device temperature closer to a constant level than would be possible by merely holding exhaust air temperature constant. In other words, although the exhaust air temperature may vary as inlet or ambient air temperature varies, the temperature of a typical semiconductor junction will remain more nearly constant than the exhaust air temperature even though it is the exhaust air temperature which is being used as the sensed parameter in the control loop.
In order to assure that the fan 15 starts upon initial application of power, even if the ambient temperature is quite low, the system of FIG. 1 is arranged to cause full power to be applied for several tenths of a second when the system is initially energized. This function is provided by the transistor Q7, the capacitor C4, the resistor R12. When power is initially applied, the transistor Q7 conducts until the capacitor C4 is charged through the base of transistor Q7 and a resistor R12. Conduction through transistor Q7 lowers the voltage supplied to the base terminals of transistors Q4 and Q5 temporarily causing the transistor Q6 to conduct and which in turn causes full power to be applied to the fan.
While the circuit of FIG. 1 provides optimal temperature control of representative or typical semiconductor packages, it will be understood by those skilled in the art that some electronic equipments may be atypical, e.g. including power transistors or multiple exhaust ports. To provide for such and similar contingencies, the circuit of FIG. 3 provides for additional temperature sensors. Such additional sensors, designated TN, TN+1, etc., are connected in separate, respective voltage divider circuits similar to that single one in FIG. 1 and each voltage divider circuit controls a respective transistor QN, QN+1, etc. These additional transistors are connected with their collector-emitter circuits across the collector-emitter circuits of Q5, i.e. in parallel with transistor Q6. Thus, these additional control signals are in effect logically ORed with the base or reference control signal which maintains the sharply defined minimum just as is the air temperature control signal provided by the thermistor T1. Thermistors TN, TN+1 may sense temperature at other exhaust ports or at other critical points or they may be connected directly to the cases of heat generating devices or to their heat sinks. Thus, if any one of these devices exceeds their respective threshold determined by the values in the respective voltage divider, increased air flow will be generated. In general, it will be understood that this functionality performs as a safety measure which is separate from and in addition to the main constant temperature maintaining function described previously.
In view of the foregoing, it may be seen that the several objects of the present invention are achieved and other advantageous results have been attained.
As various changes could be made in the above constructions without departing from the scope of the invention, it should be understood that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | The fan speed controller disclosed herein is particularly useful in the cooling of electronic equipment and provides a feedback control characteristic from an exhaust air temperature sensor such that the change in outlet temperature over the range of air flow rates is substantially equal to the change in temperature rise of typical heat generating devices in electronic equipment over that same range. Accordingly, device temperature is maintained substantially constant over a range of varying input air temperatures. Preferably, the controlled fan includes a d.c. motor which is energized in a pulsed d.c. mode to prevent stalling or instability at low flow rates. | 6 |
This is a Rule 60 Divisional of U.S. patent application Ser. No. 08/297,494, U.S. Pat. No. 5,580,771 filed Aug. 29, 1994, which in turn is a Rule 60 Divisional of U.S. patent application Ser. No. 07/872,644, U.S. Pat. No. 5,389,527 filed Apr. 20, 1992, which is a continuation-in-part of our U.S. patent application No. 07/688,356, filed Apr. 19, 1991, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to novel purified and isolated nucleotide sequences encoding mammalian Ca 2+ /calmodulin stimulated phosphodiesterases (CaM-PDEs) and cyclic-GMP-stimulated phosphodiesterases (cGS-PDEs). Also provided are the corresponding recombinant expression products of said nucleotide sequences, immunological reagents specifically reactive therewith, and procedures for identifying compounds which modulate the enzymatic activity of such expression products.
Cyclic nucleotides are known to mediate a wide variety of cellular responses to biological stimuli. The cyclic nucleotide phosphodiesterases (PDEs) catalyze the hydrolysis of 3', 5' cyclic nucleotides, such as cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), to their corresponding 5'-nucleotide monophosphates and are consequently important in the control of cellular concentration of cyclic nucleotides. The PDEs in turn are regulated by transmembrane signals or second messenger ligands such as calcium ion (Ca 2+ ) or cGMP. The PDEs thus have a central role in regulating the flow of information from extracellular hormones, neurotransmitters, or other signals that use the cyclic nucleotides as messengers.
PDEs are a large and complex group of enzymes. They are widely distributed throughout the cells and tissues of most eukaryotic organisms, but are usually present only in trace amounts. At least five different families of PDEs have been described based on characteristics such as substrate specificity, kinetic properties, cellular regulatory control, size, and in some instances, modulation by selective inhibitors. Beavo, Adv. in Second Mess. and Prot. Phosph. Res. 22:1-38 (1988)!. The five families include:
I Ca 2+ /calmodulin-stimulated
II cGMP-stimulated
III cGMP-inhibited
IV cAMP-specific
V cGMP-specific
Within each family there are multiple forms of closely related PDEs. See Beavo, "Multiple Phosphodiesterase Isozymes Background, Nomenclature and Implications", pp. 3-15; Wang et al., "Calmodulin-Stimulated Cyclic Nucleotide Phosphodiesterases", pp. 19-59; and Manganiello et al., "Cyclic GMP-Stimulated Cyclic Nucleotide Phosphodiesterases" pp. 62-85; all in Cyclic Nucleotide Phosphodiesterases: Structure. Regulation and Drug Action, Beavo, J. and Houslay, M. D., Eds.; John Wiley & Sons, New York (1990).
The Ca 2+ /calmodulin dependent PDEs (CaM-PDEs) are characterized by their responsiveness to intracellular calcium, which leads to a decreased intracellular concentration of cAMP and/or cGMP. A distinctive feature of cGMP-stimulated phosphodiesterases (cGS-PDEs) is their capacity to be stimulated by cGMP in effecting cAMP hydrolysis.
In vitro studies have shown increased PDE activity in response to Ca 2+ /calmodulin in nearly every mammalian tissue studied, as well as in Drosophila, Dictyostelium, and trypanosomes. The level of CaM-PDE in tissues and cellular and subcellular compartments varies widely. Most cells contain at least a small amount of CaM-PDE activity, with the highest tissue levels being found in the brain, particularly in the synaptic areas. Greenberg et al. Neuropharmacol., 17:737-745 (1978) and Kincaid et al., PNAS (USA), 84:1118-1122 (1987). A decrease in cAMP in astrocytoma cells in response to muscarinic stimulation may be due to calcium dependent increases in CaM-PDE activity. Tanner et al., Mol. Pharmacol., 29:455-460 (19B6). Also, CaM-PDE may be an important regulator of cAMP in thyroid tissue. Erneux et al., Mol. Cell. Endocrinol., 43:123-134(1985).
Early studies suggested that there are distinct tissue-specific isozymes of CaM-PDEs. Several members of the CaM-PDE family have now been described, including a 59 kDa isozyme isolated from bovine heart, and 61 and 63 kDa isozymes isolated from bovine brain. LaPorte et al., Biochemistry, 18:2820-2825 (1979); Hansen et al., Proc. Natl. Acad. Sci. USA, 79:2788-2792 (1982); and Sharma et al., J. Biol. Chem., 261:3.4160-14166 (1986). Possible counterparts to the bovine 59 and 61 kDa isozymes have also been isolated from rat tissues, Hansen et al., J. Biol. Chem., 261:14636-14645 (1986), suggesting that these two isozymes may be expressed in other mammalian species.
In addition to molecular weight criteria, other evidence supports both similarities and differences among the CaM-PDE family of isozymes. For example, the 59 kDa heart isozyme and the 61 kDa brain isozyme CaM-PDEs differ in mobility on SDS-PAGE and elution position on DEAE chromatography, and the 59 kDa isozyme has at least a 10-20 fold higher affinity for calmodulin. Oncomodulin, a fetal/onco calcium binding protein present in very high concentrations in the placenta and transformed cells, also hinds to the 59 kDa enzyme with a higher affinity than to the 61 kDa enzyme. However, both the 61 kDa brain and the 59 kDa heart isozymes are recognized by a single monoclonal antibody. This antibody binds to the Ca 2+ /CaM-PDE complex with 100-fold higher affinity than to PD. alone. Hansen et al., 1986, supra. The 59 and 61 kDA isozymes have nearly identical substrate specificities and kinetic constants. Krinks et al., Adv. Cyc. Nucleotide Prot. Phosphorylation Res., 16:31-47 (1984) have suggested, based on peptide mapping experiments, that the heart 59 kDa protein could be a proteolytic form of the brain 61 kDa isozyme.
The 63 kDa bovine brain isozyme differs substantially from the 59 and 61 kDa isozymes. The 63 kDa enzyme is not recognized by the monoclonal antibody which binds to the 59 and 61 kDa enzymes. Hansen et al., 1986, supra. The 63 kDa protein is not phosphorylated in vitro by cAMP-dependent protein kinase, whereas the 61 kDa protein is phosphorylated. Further, only the 63 kDa protein is phosphorylated in vitro by CaM-kinase II. Sharma et al., Proc. Natl. Acad. Sci. (USA), 82:2603-2607 (1985); and Hashimoto et al., J. Biol. Chem., 264:10884-10887 (1989). The 61 and 63 kDa CaM-PDE isozymes from bovine brain do appear, however, to have similar CaM-binding affinities. Peptide maps generated by limited proteolysis with Staphylococcal V8 protease, Sharma et al., J. Biol.Chem., 259:9248 (1984), have suggested that the 61 and 63 kDa proteins; have different amino acid sequences.
The cGMP-stimulated PDEs (cGS-PDEs) are proposed to have a noncatalytic, cGMP-specific site that may account for the stimulation of cAMP hydrolysis by cGMP. Stoop et al., J.Biol.Chem., 264:13718 (1989). At physiological cyclic nucletotide concentrations, this enzyme responds to elevated cGMP concentrations with an enhanced hydrolysis of cAMP. Thus, cGS-PDE allows for increases in cGMP concentration to moderate or inhibit cAMP-mediated responses. The primary sequence presented recently in LeTrong et al., Biochemistry, 29:10280 (1990), co-authored by the inventors herein, provides the molecular framework for understanding the regulatory properties and domain substructure of this enzyme and for comparing it with other PDE isozymes that respond to different signals. This publication also notes the cloning of a 2.2 kb bovine adrenal cortex cDNA fragment encoding cGS-PDE. See also, Thompson et al., FASEB J., 5(6):Al592 (Abstract No. 7092) reporting on the cloning of a "Type II PDE" from rat pheochromocytoma cells.
With the discovery of the large number of different PDEs and their critical role in intracellular signalling, efforts have focused on finding agents that selectively activate or inhibit specific PDE isozymes. Agents which affect cellular PDE activity, and thus alter cellular cAMP, can potentially be used to control a broad range of diseases and physiological conditions. Some drugs which raise cAMP levels by inhibiting PDEs are in use, but generally act as broad nonspecific inhibitors and have deleterious side effects on cAMP activity in nontargeted tissues and cell types. Accordingly, agents are needed which are specific for selected PDE isozymes. Selective inhibitors of specific PDE isozymes may be useful as cardiotonic agents, anti-depressants, anti-hypertensives, anti-thrombotics, and as other agents. Screening studies for agonists/antagonists have been complicated, however, because of difficulties in identifying the particular PDE isozyme present in a particular assay preparation. Moreover, all PDEs catalyze the same basic reaction; all have overlapping substrate specificities; and all occur only in trace amounts.
Differentiating among PDEs has been attempted by several different mean. The classical enzymological approach of isolating and studying each new isozyme is hampered by current limits of purification techniques and by the inability to accurately assess whether complete resolution of an isozyme has been achieved. A second approach has been to identify isozyme-specific assay conditions which might favor the contribution of one isozyme and minimize that of others. Another approach has been the immunological identification and separation into family groups and/or individual isozymes. There are obvious problems with each of these approaches; for the unambiguous identification and study of a particular isozyme, a large number of distinguishing criteria need to be established, which is often time consuming and in some cases technically quite difficult. As a result, most studies have been done with only partially pure PDE preparations that probably contained more than one isozyme. Moreover, many of the PDEs in most tissues are very susceptible to limited proteolysis and easily form active proteolytic products that may have different kinetic, regulatory, and physiological properties from their parent form.
The development of new and specific PDE-modulatory agents would be, greatly facilitated by the ability to isolate large quantities of tissue-specific PDEs by recombinant means. Relatively few PDE genes have been cloned to date and of those cloned, most belong to the cAMP-specific family of phosphodiesterases (cAMP-PDEs). See Davis, "Molecular Genetics of the Cyclic Nucleotide Phosphodiesterases", pp. 227-241 in Cyclic Nucleotide Phosphodiesterases: Structure, Regulation, and Drug Action, Beavo, J and Houslay, M. D., Eds.; John Wiley & Sons, New York; 1990. See also, e.g., Faure et al., PNAS (USA), 85:8076 (1988)--D. discoideum; Sass et al., PNAS (USA), 83:9303 (1986)--S. cerevisiae, PDE class IV, designated PDE2; Nikawa et al., Mol. Cell. Biol., 7:3629 (1987)--S. cerevisiae, designated PDE1; Wilson et al., Mol. Cell. Biol., 8:505 (1988)--S. cerevisiae, designated SRA5; Chen et al., PNAS (USA), 83:9313 (1986)--D. melanogaster, designated dnc + ; Ovchinnikow et al., FEBS, 223:169 (1987) bovine retina, designated GMP PDE; Davis et al., PNAS (USA), 86:3604 (1989)--rat liver, designated rat dnc-1; Colicelli et al., PNAS (USA), 86:3599 (1989)--rat brain, designated DPD; Swinnen et al., PNAS (USA), 86:5325 (1989)--rat testis, rat PDE1, PDE2, PDE3 and PDE4; and Livi et al., Mol. Cell. Biol., 10:2678 (1990)--human monocyte, designated hPDE1. See also, LeTrong et al., supra and Thompson et al., supra.
Complementation screening has been used to detect and isolate mammalian cDNA clones encoding certain types of PDEs. Colicelli et al., PNAS (USA), 86:3599 (1989), reported the construction of a rat brain cDNA library in an S. cerevisiae expression vector and the isolation therefrom of genes having the capacity to function in yeast to suppress the phenotypic effects of RAS2 va119 , a mutant form of the RAS2 gene analogous to an oncogenic mutant of the human HRAS gene. A cDNA so cloned and designated DPD (rat dunce-like phosphodiesterase) has the capacity to complement or "rescue" the loss of growth control associated with an activated RAS2 va119 gene harbored in yeast strain TK161-R2V (A.T.C.C. 74050), as well as the analogous defective growth control phenotype of the yeast mutant 10DAB (A.T.C.C. 74049) which is defective at both yeast PDE gene loci (pde -1 , pde -2 ). The gene encodes a high-affinity cAMP specific phosphodiesterase, the amino acid sequence of which is highly homologous to the cAMP-specific phosphodiesterase encoded by the dunce locus of Drosophila melanogaster.
Through the date of filing of parent application Ser. No. 07/688,356, there have been no reports of the cloning and expression of DNA sequences encoding any of the mammalian Ca 2+ /calmodulin stimulated or cGMP-stimulated PDEs (PDE families I and II) and, accordingly, there continues to exist a need in the art for complete nucleotide sequence information for these PDEs.
BRIEF SUMMARY OF THE INVENTION
The present invention provides novel purified and isolated polynucleotide sequences (e.g. DNA and RNA including sense and antisense strands) which code for expression of mammalian species (e.g., human and bovine) Ca 2+ /calmodulin stimulated cyclic nucleotide phosphodiesterase and cGMP stimulated cyclic nucleotide phosphodiesterase polypeptides. Genomic and cDNA sequences provided by the invention may be associated with homologous or heterologous species expression control DNA sequences such as promoters, operators, regulators, terminators and the like to allow for in vivo and in vitro transcription to messenger RNA and, in turn, translation of mRNAs to provide functional phosphodiesterases and related polypeptides in large quantities.
Specifically provided by the invention are mammalian DNA sequences encoding phosphodiesterases and fragments thereof which are present as mammalian DNA inserts in bacterial plasmids and viral vectors which are the subject of deposits made with the American Type Culture Collection, 12301 Parklawn Drive, Rockville, Md. 20852 on Apr. 11 and 15, 1991 and on Apr. 14, 1992 in accordance with U.S. Patent and Trademark Office and Budapest Treaty requirements. DNAs deposited in connection with the present invention include:
1. Plasmid pCAM-40 in E. coli (A.T.C.C. accession No. 68576) containing a bovine brain cDNA insert encoding a 61 kDa CaM-PDE isozyme;
2. Plasmid p12.3A in E. coli (A.T.C.C. 68577) containing a bovine brain cDNA insert encoding a 63 kDa CaM-PDE isozyme;
3. Bacteriophage λ CaM H6a (A.T.C.C. accession No. 75000) containing a human hippocampus cDNA insert fractionally encoding a 61 kDa CaM-PDE isozyme;
4. Plasmid pHcam61-6N-7 in E. coli (A.T.C.C. accession No. 68963) containing a composite human cDNA insert encoding a 61 kDa CaM-PDE isozyme;
5. Plasmid pcamH3EF in E. coli (A.T.C.C. accession No. 68964) containing a human hippocampus cDNA insert encoding a novel PDE homologous to a 61 kDa CaM-PDE;
6. Plasmid pcamHella in E. coli (A.T.C.C. accession No. 68965) containing a human heart cDNA insert encoding a novel PDE homologous to a 61 kDa CaM-PDE;
7. Plasmid p3CGS-5 in E. coli (A.T.C.C. accession No. 68579) containing a bovine adrenal cDNA insert encoding a cGS-PDE isozyme;
8. Plasmid pBBCGSPDE-5 in E. coli (A.T.C.C. accession No. 68578) containing a bovine brain cDNA insert encoding a cGS-PDE isozyme fragment;
9. Plasmid pBBCGSPDE-7 in E. coli (A.T.C.C. accession No. 68580) containing a bovine brain cDNA encoding a cGS-PDE isozyme;
10. Plasmid pGSPDE6.1 in E. coli (A.T.C.C. accession No. 68583) containing a human heart cDNA encoding a cGS-PDE isozyme fragment;
11. Plasmid pGSPDE7.1 in E. coli (A.T.C.C. accession No. 68585) containing a human hippocampus cDNA insert encoding a cGS-PDE isozyme fragment; and
12. Plasmid pGSPDE9.2 (A.T.C.C. accession No. 68584) containing a human hippocampus cDNA insert encoding a cGS-PDE isozyme fragment. 13. Plasmid pHcgs6n in E. coli (A.T.C.C. accession No. 68962) containing a human cDNA insert encoding a cGS-PDE.
Also specifically provided by the present invention is a bovine cDNA sequence containing nucleotides encoding bovine 59 kDa CaM-PDE and characterized by the DNA and amino acid sequences of SEQ ID NO: 16 and SEQ ID NO: 17.
In related embodiments, the invention concerns DNA constructs which comprise a transcriptional promoter, a DNA sequence which encodes the PDE or a fragment thereof, and a transcriptional terminator, each operably linked for expression of the enzyme or enzyme fragment. The constructs are preferably used to transform or transfect host cells, preferably eukaryotic cells, and more preferably mammalian or yeast cells. For large scale production, the expressed PDE can be isolated from the cells by, for example, immunoaffinity purification.
Incorporation of DNA sequences into procaryotic and eucaryotic host cells by standard transformation and transfection processes, potentially involving suitable DNA and RNA viral vectors and circular DNA plasmid vectors, is also within the contemplation of the invention and is expected to provide useful proteins in quantities heretofore unavailable from natural sources. Systems provided by the invention include transformed E. coli cells, including those referred to above, as well as other transformed eukaryotic cells, including yeast and mammalian cells. Use of mammalian host cells is expected to provide for such post-translational modifications (e.g., truncation, lipidation, and tyrosine, serine or threonine phosphorylation) as may be needed to confer optimal biological activity on recombinant expression products of the invention.
Novel protein products of the invention include expression products of the aforementioned nucleic acid sequences and polypeptides having the primary structural conformation (i.e., amino acid sequence) of CaM-PDE and cGS-PDE proteins, as well as peptide fragments thereof and synthetic peptides assembled to be duplicative of amino acid sequences thereof. Proteins, protein fragments, and synthetic peptides of the invention are projected to have numerous uses including therapeutic, diagnostic, and prognostic uses and will provide the basis for preparation of monoclonal and polyclonal antibodies specifically immunoreactive with the proteins of the invention.
Also provided by the present invention are antibody substances (including polyclonal and monoclonal antibodies, chimeric antibodies, single chain antibodies and the like) characterized by their ability to bind with high immunospecificity to the proteins of the invention and to their fragments and peptides, recognizing unique epitopes which are not common to other proteins. The monoclonal antibodies of the invention can be used for affinity purification of CaM-PDEs and cGS-PDEs, e.g., Hansen et al., Meth. Enzymol., 159:543 (1988).
Also provided by the present invention are novel procedures for the detection and/or quantification of normal, abnormal, or mutated forms of CaM-PDEs and cGS-PDEs, as well as nucleic acids (e.g., DNA and mRNA) associated therewith. Illustratively, antibodies of the invention may be employed in known immunological procedures for quantitative detection of these proteins in fluid and tissue sample, and of DNA sequences of the invention that may be suitably labelled and employed for quantitative detection of mRNA encoding these proteins.
Among the multiple aspects of the present invention, therefore, is the provision of (a) novel CaM-PDE and cGS-PDE encoding polynucleotide sequences, (b) polynucleotide sequences encoding polypeptides having the activity of a mammalian CaM-PDE or of a mammalian cGS-PDE which hybridize to the novel CaM-PDE and cGS-PDE encoding sequences under hybridization conditions of the stringency equal to or greater than the conditions described herein and employed in the initial isolation of cDNAs of the invention, and (c) polynucleotide sequences encoding the same (or allelic variant or analog polypeptides) through use of, at least in part, degenerate codons. Correspondingly provided are viral DNA and RNA vectors or circular plasmid DNA vectors incorporating polynucleotide sequences and procaryotic and eucaryotic host cells transformed or transfected with such polynucleotide sequences and vectors, as well as novel methods for the recombinant production of these proteins through cultured growth of such hosts and isolation of the expressed proteins from the hosts or their culture media.
In yet other embodiments, the invention provides compositions and methods for identifying compounds which can modulate PDE activity. Such methods comprise incubating a compound to be evaluated for PDE modulating activity with eukaryotic cells which express a recombinant PDE polypeptide and determining therefrom the effect of the compound on the phosphodiesterase activity provided by gene expression. The method is effective with either whole cells or cell lysate preparations. In a preferred embodiment, the eukaryotic cell is a yeast cell or mammalian cell which lacks endogenous phosphodiesterase activity. The effect of the compound on phosphodiesterase activity can be determined by means of biochemical assays which monitor the hydrolysis of cAMP and/or cGMP, or by following the effect of the compound on the alteration of a phenotypic trait of the eukaryotic cell associated with the presence or absence of the recombinant PDE polypeptide.
Other aspects and advantages of the present invention will be apparent upon consideration of the following detailed description thereof which includes numerous illustrative examples of the practice of the invention, reference being made to the drawing wherein:
FIG. 1 provides the results of amino acid sequence determinations for isolated 59 kDa (bovine heart) and 63 kDa (bovine brain) CaM-PDE proteins in alignment with the complete sequence of the 61 kDa (bovine brain) isozyme. Identities of the 59 and 63 kDa proteins to the 61 kDa isozyme are underlined. Tentative identifications are in lower cases and hyphens denote unidentified residues. The N-terminus of the 59 kDa isozyme, as determined by the subtraction of a methionyl peptide (mDDHVTIRRK) from the composition of an amino-terminal blocked lysyl peptide, is in parenthesis. Solid boxes are placed above residues within the CaM-binding sites identified in the 61 and 59 kDa isozymes.
DETAILED DESCRIPTION OF THE INVENTION
The following examples illustrate practice of the invention. Example I relates to the isolation, purification, and sequence determination of 61 kDa CaM-PDE cDNA from bovine brain and to the expression thereof in a mammalian host cell. Example II relates to the isolation, purification, and sequence determination of a 59 kDa CaM-PDE from bovine lung and to the expression thereof in a mammalian host cell. Example III relates to the isolation, purification, and sequence determination of 63 kDa CaM-PDE cDNA from bovine brain and to the expression thereof in a mammalian host cell. Example IV relates to the isolation, purification, and sequence determination of CGS-PDE cDNA from bovine adrenal cortex, as well as the expression of the DNA in mammalian host cells. Example V relates to the isolation, purification, and sequence determination of cGS-PDE cDNA from bovine brain and to the expression thereof in a mammalian host cell. Example VI relates to the use of CGS-PDE bovine adrenal cDNA to obtain human cGS-PDE cDNAs and to the development of a human cDNA encoding a cGS-PDE. Example VII relates to the use of CaM-PDE 61 kDa bovine brain cDNA to obtain a human CaM-PDE 61 kDa cDNA and a novel structurally related cDNA. Example VIII relates to the expression of bovine and human PDE cDNAs for complementation of yeast phenotypic defects and verification of phosphodiesterase activity for the expression product. Example IX relates to tissue expression studies involving Northern analysis and RNase protection studies employing polynucleotides (specifically cDNAs and antisense RNAs) of the invention.
In those portions of the text addressing the formation of redundant oliqonucleotides, the following Table I single letter code recommendations for ambiguous nucleotide sequence, as reported in J.Biol.Chem., 261:13-17 (1986), are employed:
TABLE I______________________________________Symbol Meaning Origin of designation______________________________________G G GuanineA A AdenineT T ThymineC C CytosineR G or A puRineY T or C pYrimidineM A or C aMinoK G or T KetoS G or C Strong interaction (3 H bonds)W A or T Weak interaction (2 H bonds)H A, C, or T not G, as H follows G in the alphabetB G, C, or T not AV A, C, or G not T, (not U) as V follows UD A, G, or T not CN A, C, G, or T any Nucleotide base______________________________________
EXAMPLE I
Isolation, Purification, and Sequence Determination of 61 kDa CaM-PDE cDNA From Bovine Brain
In this Example, a cDNA sequence representing that portion of a gene for 61 kDa bovine brain CaM-PDE which encodes the amino terminus of the protein was isolated by PCR from a collection of first strand cDNAs developed from bovine brain mRNA. The PCR-generated fragment was then employed to isolate a full length bovine brain CaM-PDE sequence.
Total RNA was prepared from bovine heart using the method of Chomczynski et al., Anal.Biochem., 162:156-159 (1987) and mRNA was selected using a Poly(A) QuikTm mRNA purification kit according to the manufacturer's protocol. First strand cDNA was synthesized by adding 80 units of AMV reverse transcriptase to a reaction mixture (40 μl, final volume) containing 50 mM Tris HCl (pH8.3@ 42°), 10 mM MgCl 2 , 10 mM dithiothreitol, 0.5 mM (each) deoxynucleotide triphosphates, 50 mM KC1, 2.5 mM sodium pyrophosphate, 5 μg deoxythymidylic acid oligomers (12-18 bases) and 5 μg bovine heart mRNA denatured for 15 min at 65°. Incorporation of 1 μl 32 P!-labeled dCTP (3000 Ci/mmol) was used to quantitate first strand cDNA synthesis. The reaction was incubated at 42° for 60 min. The reaction was phenol/CHCl 3 extracted and EtOH precipitated. The nucleic acid pellet was resuspended in 50 μl of 10 mM Tris-HCl (pH 7.5)/0.1 mM EDTA to a final concentration of 15 ng per μl.
Redundant sense and antisense oligomers corresponding to 61 kDa peptide sequences as in FIG. 1 were designed to be minimally redundant, yet long enough to specifically hybridize to the target template.
A first 23 base oligomer, designated CaM PCR-2S, was synthesized on an Applied Biosystems, Inc. DNA synthesizer. The oligomer had the following sequence, ##STR1## which specifies the following amino acid sequence, ##STR2##
A second 23 base oligomer, designated CaM PCR-3AS, was synthesized with the following sequence, ##STR3## representing the following amino acid sequence, ##STR4##
A 612 bp CaM PDE cDNA fragment was synthesized using the PCR amplification technique by adding 15 ng of first strand cDNA to a reaction mixture containing 50 mM KC1, 10 mM Tris-HCl (pH 9.0), 1.5 mM MgCl 2 , 0.01% gelatin, 0.1% Triton X-100, 0.2 mM (each) deoxynucleotide triphosphates, 1 μM (each) CaM PCR 2S and CaM PCR-3AS oligomers, and 2.5 units of Thermus aquaticus DNA polymerase. The reaction was incubated for 30 cycles as follows: 94° for 1 min; 50° for 2 min; and 72° for 2 min. The reaction products were purified on a 1% agarose gel using 0.04M Tris-acetate/0.001M EDTA buffer containing 0.5 μg/ml ethidium bromide. The DNA products were visualized with UV light, cleanly excised from the gel with a razor blade, purified using Geneclean II reagent kit and ligated into Eco RV-cut pBluescript vector DNA.
To determine if the PCR amplification products were CaM PDE cDNAs, the subcloned PCR DNA products were sequenced from the ends using T3 and T7 promoter primers and either Sequenase or Taq Polymerase sequencing kits. Approximately 250 bases from each end of this piece of DNA were sequenced and the deduced amino acid sequence from the cDNA corresponded with the FIGS. 1A-1C amino acid sequences of the 59 and 61 kDa CaM-PDEs, confirming that the PCR DNA product was a partial CaM PDE cDNA.
A bovine brain cDNA library constructed with the lambda ZAP vector (kindly provided by Ronald E. Diehl, Merck, Sharp & Dohme) was screened with the radiolabeled 615 bp CaM-PDE cDNA obtained by PCR amplification. The probe was prepared using the method of Feinberg et al., Anal.Biochem., 137:266-267 (1984), and the 32 P!-labeled DNA was purified using Elutip-D® columns. Plaques (700,000 plaques on 12-150 mm plates) bound to filter circles were hybridized at 42° C. overnight in a solution containing 50% formamide, 20 mM Tris-HCl (pH 7.5), 1X Denhardt's solution, 10% dextran sulfate, 0.1% SDS and 10 6 cpm/ml 32 !-labeled probe (10 9 cpm/μg). The filters were washed three times for 15 min with 2X SSC/0.1% SDS at room temperature, followed by two 15-min washes with 0.1X SSC/0.1% SDS at 45° C. The filters were exposed to x-ray film overnight.
Of the fifty-six plaques that hybridized with the 32 P!-labeled probes eight randomly selected clones were purified by several rounds of re-plating and screening Maniatis et al., Molecular Cloning: A Laboratory Manual 545 pp. Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y., (1982)! and the insert cDNA's were subcloned into pBluescript SK(-) by in vivo excision Short et al., Nuc. Acids Res., 16:7583-7599 (1988)! as recommended by the manufacturer.
Plasmid DNA prepared from cultures of each clone were subjected to restriction analysis using EcoRI. Two clones of a suitable length were selected for sequence analysis using Taq Tak® and Sequenase® sequencing kits. The two clones were pCAM-40 (2.3 kb) and pCAM-34 (2.7 kb). The sequencing information from this procedure confirmed that the insert of pCAM-40 encoded the full length bovine brain 61 kDa CaM-PDE. The sequence of this clone and the amino acid sequence deduced therefrom are set forth in SEQ ID NO: 5 and SEQ ID NO: 6.
Transient expression of the 61 kDa CaM-PDE cDNA in COS-7 cells (A.T.C.C. CRL 1651) was accomplished as follows. Vector pCDM8 Seed, Nature, 329:840-843 (1987)! in E. coli host cells MC1061-p3 was generously provided by Dr. Brian Seed, Massachusetts General Hospital, Boston, Mass. This vector is also available from Invitrogen, Inc. (San Diego, Calif.). Plasmid pCAM-40 was digested with HindIII and NotI, yielding a 2.3 kb fragment which was ligated into CDM8 vector DNA which had been digested with HindIII and NotI. The resulting plasmid was propagated in MC1061-p3 cells. Plasmid DNA was prepared using the alkaline lysis method of Ausubel et al., eds., Current Protocols in Molecular Biology, 1:1.7.1 (John Wiley & Sons, New York, 1989) and purified using Qiagen-Tip 500 columns (Qiagen, Inc. Chatsworth, Calif.) according to the manufacturer protocol.
COS-7 cells were transfected with the p-CAM-40/CDM8 construct (or mock transfected with the CDM8 vector alone) using the DEAE-dextran method Ausubel et al., supra at 1:9.2 et seq. Specifically, 10 μg of ethanol precipitated DNA was resuspended in 80 μl TBS buffer, and added to 160 μl of 10 mg per ml DEAE-dextran dropwise to a 100 mm plate of 50% confluent COS-7 cells in 4 ml of DMEM supplemented with 10% NuSerum, and mixed by swirling. The cells were incubated for 3-4 hours at 37° in a water-saturated 7% CO 2 atmosphere. The medium was removed and the cells were immediately treated with 10% DMSO in PBS for 1 minute. Following this treatment, the cells were washed with PBS, then DMEM, and finally cultured in DMEM supplemented with 10% fetal bovine serum and antibiotics (50 μg/ml streptomycin sulfate) in a 7%-CO 2 incubator for 36 hours.
COS cells were scraped from the plates and homogenized in a buffer containing 40 mM Tris-HCl (pH=7.5), 5 mM EDTA, 15 mM benzamidine, 15 mM beta-mercaptoethanol, 1 μg per ml pepstatin A and 1 μg per ml peupeptin using a Dounce homogenizer (1 ml per 100 mm plate). Homogenates were assayed for PDE activity according to the procedures of Hanson et al., Proc. Nat'l. Acad. Sci., U.S.A., 79:2788-2792 (1982), using 3 H!cGMP as the substrate. Reactions were carried out at 30° for 10 minutes in a buffer containing 20 mM Tris-HCl (pH=7.5), 20 mM imidazole (pH=7.5), 3 mM MgCl 2 , 15 mM μg acetate, 0.2 mg per ml BSA and 1 μM 3 H-cAMP with either 2 mM EGTA or 0.2 mM CaCl 2 and 4 μg per ml CaM. Assays were stopped by incubating the tubes in a 90° water bath for 1 minute. After cooling, 10 μl of 2.5 mg per ml snake venom was added to each assay and incubated at 37° for 5 minutes. The samples were diluted with 250 μl of 20 mM Tris-HCl (pH=7.5) and immediately applied to 0.7 ml A-25 ion exchange columns. The columns were washed three times with 0.5 ml of 20 mM Tris-HCl (pH=7.5) and the eluate was collected in scintillation vials. Samples were counted for 1 minute using a Packard Model 1600TR scintillation counter. Specific cyclic nucleotide hydrolytic activity was expressed as picomoles cAMP or cGMP hydrolyzed per minute per mg protein. Protein concentration was estimated according to the method of Bradford, Anal. Biochem., 72:248-254 (1976), using BSA as a standard. When compared to mock transfected cells, extracts of cells transfected with pCAM-40 cDNA contained significantly greater CAMP and cGMP hydrolytic activities in the presence of EGTA. Assays of the pCAM-40 cDNA-transfected cells in the presence of calcium and CaM resulted in stimulation of cAMP and cGMP hydrolysis.
EXAMPLE II
Isolation, Purification, and Sequence Determination of a 59 kDa CaM-PDE From Bovine Lung
A fully degenerate sense oligonucleotide corresponding to the amino acid sequence ##STR5## from the bovine heart 59 kDa CaM-pde was synthesized. The nucleotide sequence of this oligonucleotide is ##STR6## An antisense oligonucleotide was designed from the FIGS.1A-1C sequence of bovine brain 61 kDa CaM-PDE, corresponding to the amino acid sequence ##STR7## and having the sequence, ##STR8## This primer pair was used to prime a PCR reaction using bovine heart first strand cDNA (as prepared in Example I) as a template. This predicted a PCR product of 75 bp, 54 bp of which were unique 59 kDa sequence and 21 bp of which were shared between the 59 kDa and 61 kDa isozymes. The PCR products were analyzed by sieving agarose gel electrophoresis, and a bard migrating at 75 bp was excised from the gel. The DNA was subcloned into pBluescript KS + , and colonies positive by the blue/white selection scheme were screened by PCR using primers directed against vector sequences. Colonies with inserts of the appropriate size were selected, and one of these (pCaM59/75.14) was chosen for sequencing. Plasmid DNA was prepared using a Qiagen P20 push column and used as template for sequencing using the dideoxy method. The sequence of the PCR product is ##STR9## Analysis of the sequence revealed differences in two codons between the sequence obtained and the predicted sequence. Re-examination of the sense oligonucleotide primer sequence revealed that an inadvertent transposition of two codons had led to a mistake in the design of the oligonucleotide. A second set of oligonucleotide PCR primers was prepared which predicted a 54 bp product with minimum overlap between the 59 and 61 kDa isozymes; in addition, the second sense primer incorporated a correction of the mistake in the design of the original sense primer. The sense oligonucleotide had the sequence ##STR10## and the antisense oligonucleotide had the sequence ##STR11## This primer pair was used to prime a PCR reaction using bovine heart first-strand cDNA as template and the PCR products subcloned and screened exactly as described above. Two clones (pCaM59/54.9 and pCaM59/54.10) were selected for sequencing based on insert size and sequenced as described above; both clones contained 54 bp inserts of the predicted sequence ##STR12## predicting the amino acid sequence ##STR13##
A cDNA library was constructed from bovine lung mRNA and screened using procedures as described in Example IV, infra, with respect to screening of a bovine adrenal cortex library. Approximately 1.2×10 6 plaque-forming units were probed with a 32 P-labelled, 1.6 kb EcoRI restriction endonuclease-cleavage product of the pCAM-40 cDNA. This initial screening produced 4 putative 59 kDA CaM-PDE cDNA clones. Preliminary sequence analysis indicated that one clone, designated p59KCAMPDE-2, contained the complete coding sequence of the putative 59 kDa CaM-PDE. A series of nested deletions were constructed from the p59KCAMPDE-2 plasmid See, Sonnenburg et al., J. Biol. Chem., 266 (26): 17655-17661 (1991)!, and the resultant templates were sequenced by an adaptation of the method of Sanger using the Taq DyeDeoxy™ Terminator Cycle Sequencing Kit and an Applied Biosystems Model 373A DNA Sequencing System. The DNA and deduced amino acid sequences are set out in SEQ. ID NO: 16 and 17, respectively. A large open reading frame within the cDNA encodes a 515 residue polypeptide with an estimated molecular weight of ≅59 kilodaltons that is nearly identical to the 61 kDa CaM-PDE amino acid sequence except for the amino-terminal 18 residues. Moreover, the predicted amino acid sequence of the p59KCAMPDE-2 open reading frame is identical to the available sequence of the 59 kDa CaM-PDE purified from bovine heart, Novack et al., Biochemistry, 30:7940-7947 (1991). These results indicate that the p59KCAMPDE-2 cDNA represents an mRNA species encoding the 59 kDa CaM-PDE.
Transient expression of the 59 kDa bovine lung PDE was accomplished as in Example I. Specifically, a 2.66 kb, EcoRI/blunt-ended fragment of p59KCAMPDE-2 cDNA was subcloned into pCDM8 which had been digested with XhoI and blunt-ended. The recombinant plasmid, designated p59KCAMPDE-2/CDM 8was used to transiently transfect COS-7 cells and extracts prepared from transfected COS-7 cells were assayed for CaM-PDE activity using 2 μM cAMP. COS-7 cells transfected with the p59KCAMPDE-2 cDNA yielded a cAMP hydrolytic activity that was stimulated 4-5 fold in the presence of calcium and calmodulin. Mock transfected COS-7 cells had no detectable calmodulin-stimulated cAMP hydrolytic activity .
EXAMPLE III
Isolation, Purification, and Sequence Determination of 63 kDa CaM-PDE cDNA From Bovine Brain
Multiple fully and partially redundant oligonucleotides corresponding to the amino acid sequence reported in FIGS.1A-1C were synthesized for use in attempting to obtain a cDNA clone for the 63 kDa CaM-PDE. Annealing temperatures used for the polymerase chain reactions were varied between 2° to 20° C. below the theoretical melting temperature for the lowest melting oligonucleotide of each sense-antisense pair. Except for probes 63-12s and 63-13a, which are discussed below, the PCR products of each of the oligonucleotide pairs under a wide range of conditions gave multiple ethidium bromide bands when agarose gel-electrophoresed. Use of 63-12s and 63-13a resulted in a PCR product that coded for 63 kDa CaM-PDE when sequenced.
A fully redundant sense 23-mer oligonucleotide, designated 63-12s, was assembled having the following sequence ##STR14## based on an amino acid sequence, ##STR15## which is conserved in the 61 kDa bovine CaM-PDEs (see FIGS. 1A-1C. A partially redundant antisense 32-mer oligonucleotide, designated. 63-13a, had the sequence ##STR16## and was based on the following conserved sequence in the 63 kDa CaM-PDE, ##STR17##
Messenger RNA was prepared from bovine brain cerebral cortex and poly A + selected. First strand complementary DNA was produced using AMV or MMLV reverse transcriptase. De-tritylated oligonucleotides were phosphorylated using 1 mM γ- 32 P!ATP at 1×10 6 cpm/nmol and T4 polynucleotide kinase. After separation of 5' 32 p-labelled oligonucleotides from free ATP using NENsorb 20 columns, each was suspended as a 20 μM (5' phosphate) stock and combined finally at 400 nM each in the PCR. The reaction was run using 50 ng total cDNA and 200 μM dNTP to obtain about 1 μg of PCR product. The reaction had an initial denaturation step at 94° C. for 5 min followed by 30 cycles of 1 min 94° C. denaturation, an annealing step at 50° C. for 1 min, and a 2 min extension step at 72° C. Under the reaction conditions, a single ethidium bromide-staining band of 450 base pairs was obtained on agarose gel electrophoresis of 100 ng of the PCR product. Five μg of 5' phosphorylated PCR product was ligated to 15 ng EcoRV-cut Bluescript KS(+) plasmid using T4 DNA ligase in 5% PEG-6000 for 12 h at 21° C. Putative positives of XL 1-blue transformations were white colonies using isopropyl thiogalactoside (IPTG) and bromo- chloro- indolyl galactoside (Xgal) for chromogenic selection. Such picks were sequenced using T3 or T7 primers, dideoxynucleotide terminators, and Sequenase.
One resultant clone (p11.5B) had the nucleotide sequence and translated amino acid sequence provided in SEQ ID NO: 22 and SEQ ID NO: 23, respectively. The codons for the amino acids YEH found in oligonucleotide 63-12s were replaced by codons for the amino acid sequence NTR in p11.5B. This was probably due to a contaminant in 63-12s. Since the translated open reading frame (ORF) was similar to that reported in FIGS. 1A-1C for the 63 kDa CaM PDE, p11.5B was used to screen a bovine brain cDNA library for a full length cDNA clone.
A bovine brain cDNA library was constructed in λ ZAP II. First strand cDNA was treated with RNase H, E. coli DNA polymerase, and E. coli DNA ligase to synthesize second strand cDNA. The cDNA was blunt-ended by T4-DNA polymerase; EcoRI sites in the cDNA were protected with EcoRI methylase and S-adenosyl methionine and EcoRI linkers were ligated on with T4 DNA ligase. After EcoRI restriction endonuclease treatment, free linkers were separated from the cDNA by gel filtration over Sepharose CL-4B. λ ZAP II arms were ligated onto the cDNA and packaged by an in vitro Gigapack Gold packaging kit obtained from Stratagene. 9.5×10 5 recombinants were obtained with 5.8% nonrecombinant plaques as assessed by plating with IPTG and X-gal. The library was amplified once by the plate lysate method to obtain 1.4×10 7 pfu/ml.
An initial screen of a total bovine brain cDNA library in λ ZAP II was performed. 700,000 pfu were screened using 32 P-labelled oligonucleotide 63-1s at a hybridization and wash temperature of 40° C. Oligonucleotide 63-1s was it fully redundant 23-mer having the sequence ##STR18## corresponding to the amino acid sequence ##STR19## A total of 21 putative positives were picked. Subsequent rescreens were impeded by the very high background found using this screening method. Therefore, aliquots of each primary pick were pooled and 50,000 pfu of the pool were replated and rescreened with p11.5B radiolabelled by random primers and α- 32 p!dCTP. One positive was obtained, plaque-purified, and rescued as a plasmid p12.3a. Its DNA sequence is provided in SEQ ID NO: 26. Subsequently, the bovine brain cerebral cortex library was screened further with p11.5B. Two further independent clones, p12.27.9 and p12.27.11, were obtained out of a primary screen of 1.4×10 6 pfu. They were plaque-purified and rescued for sequencing.
Clone p12.3a coders for a protein sequence with most of the aligned peptides isolated from bovine 63 kDa CaM-PDE as shown in FIGS. 1A-1C SEQ ID NO: 26 and SEQ ID NO: 27 set forth the coding region (i.e., the 1844 nucleotides of an approximately 2.5 kilobase insert) of p12.3a. Base numbers 248-290 code for amino acid sequence ##STR20## while the comparable (FIGS. 1A-1C) peptide has the sequence ##STR21## Base numbers 942-990 code for an amino acid sequence ##STR22## while the isolated (FIGS.1A-1C) peptide sequence is ##STR23## None of the nonaligned 63 kDa peptide sequence is found in any reading frame of p12.3a; also, the molecular weight of the p12.3a open reading frame, as translated, is 60,951 not 63,000. Therefore, this cDNA may represent an isozyme variant of the 63 kDa protein. The other two independent clones (p12.27.9 and p12.27.11) seem to have ORF sequence identical to p12.3a. The open reading frame of one clone begins at nucleotide number 823 of p12.3a and is identical to p12.3a through its termination codon. The other clone starts at nucleotide 198 and is identical to p12.3a throughout its length. None of the three clones has the anomalous NTR peptide sequence found in p11.5B; all three have YEH as the 61 kDa CaM PDE.
Transient expression of the 63kDa CaM-PDE cDNA in COS-7 cells was accomplished as follows. A fragment of the cDNA insert of plasmid p 12.3 including the protein coding region of SEQ.ID NO: 26 and flanked by BamHI restriction sites was; prepared by PCR. More specifically, oligonucleotides corresponding to base Nos. 94-117 (with the putative initiation codon) and the antisense of base Nos. 1719-1735 (with sequence immediately 3' of the termination codon) of SEQ.ID NO. 26 were synthesized with two tandem BamHI sites on their 5' ends. The two primers had the following sequences: ##STR24##
The two oligonucleotides were used in a PCR cycling 30 times from a 1 min incubation at 94° C. to a 2 min 72° C. incubation with a final 10 min extension reaction at 72° C. The 100 μl reaction used 20 μM of each oligonucleotide and 100 pg p12.3a as the template in order to produce 5 μg 1665 base pair product.
The product was extracted once with an equal volume of 1:1 phenol:chloroform, made 0.3 M with regard to sodium acetate, and precipitated with two volumes of ethanol overnight. The precipitate was dried, rehydrated into 50 μl, and the cDNA was digested with 5 units BamHI restriction endonuclease for one hour at 37° C. Afterwards, the solution was extracted once with an equal volume of 1:1 phenol:chloroform. The 1641 base pair cDNA with BamHI 5' and 3' ends was purified from the aqueous layer using Qiagen Q-20 columns (Qiagen, Inc., Chatsworth, Calif.) and the protocol given by the manufacturer.
The cut, purified PCR product was ligated into BamHI digested, alkaline phosphatase-treated Bluescript KS(+) plasmid. The ligation product was subcloned into XL1 cells; resulting transformants were screened by sequencing. One transformant (designated p11.6.c6) was isolated with the BamHI insert oriented such that the Bluescript KS(+) HindIII restriction site was 30 bases 5' to the sequence of the insert encoding the initiation codon. This plasmid was digested with HindIII and XbaI restriction endonucleases to release the 1689 base pair fragment. The fragment was ligated into HindIII- and XbaI-digested CDM8 vector DNA as in Example I.
COS-7 cells were transfected with the p12.3.a/CDM8 construct or mock transfected with the CDM8 vector alone using the DEAE-dextran method as described in Example 1. A ratio of 10 μg DNA/400 μg DEAE-dextran was used, with a final DEAE-dextran concentration in the media of 100 μg/ml. After 48 h, cells were suspended in 1 ml of homogenization buffer (40 mM Tris HCl, pH=7.5, 15 mM benzamidine HCl, 15 mM 6-mercaptoethanol, 0.7 μg/ml pepstatin A, 0.5 μg/ml leupeptin, and 5 mM Na 4 EDTA) and disrupted on ice using a Dounce homogenizer. The homogenates were diluted 1/2 to make a final 50% (v/v) glycerol for storage at -20° C. and used either to assay for phosphodiesterase activity or to determine protein concentration. CaM-dependent and independent activities were determined as in Example 1. Cells transfected with a p12.3.a DNA had a 15-fold increase in CaM-stimulated cAMP phosphodiesterase activity and a 12-fold increase in CaM-stimulated cGMP phosphodiesterase activity over basal levels. Mock transfected COS-7 cells showed no PDE activity over basal levels even with CaM stimulation.
EXAMPLE IV
Isolation, Purification, sequence Determination, and Expression of cGS-PDE cDNA From Bovine Adrenal Cortex
Total RNA was prepared from bovine adrenal outer cortex using the method of Chomczynski et al., supra. Polyadenylated RNA was purified from total RNA preparations using the Poly(A) QuickTm mRNA purification kit according to the manufaicturer's protocol. First strand cDNA was synthesized by adding 80 units of AMV reverse transcriptase to a reaction mixture (40 μl, final volume) containing 50 mM Tris-HCl (pH 8.3@420), 10 mM MgCl 2 , 10 mM dithiothreitol, 0.5 mM (each) deoxynucleotide triphosphates, 50 mM KCl, 2.5 mM sodium pyrophosphate, 5 μg deoxythymidylic acid oligomers (12-18 bases) and 5 μg bovine adrenal cortex mRNA denatured for 15 min at 65° C. The reaction was incubated at 42° C. for 60 min. The second strand was synthesized using the method of Watson et al., DNA Cloning: A Practical Approach, 1:79-87 (1985) and the ends of the cDNA were made blunt with T4 DNA polymerase. EcoRI restriction endonuclease sites were methylated Maniatis et al., supra! using a EcoRI methylase (Promega), and EcoRI linkers (50-fold molar excess) were ligated to the cDNA using T4 DNA ligase. Excess linkers were removed by digesting the cDNA with EcoRI restriction endonuclease, followed by Sepharose CL-4B chromatography. Ausubel et al., supra. The cDNA (25-50 ng per μg vector) was ligated into EcoRI-digested, dephosphorylated ZAP® II (Stratagene) arms Short et al., Nuc.Acids Res., 16:7583-751)9 (1988)! and packaged Maniatis et al., supra! with Gigapack® Gold extracts according to the manufacturer's protocol.
Initially, an unamplified bovine adrenal cortex cDNA library was made and screened with a redundant 23-mer antisense oligonucleotide probes end-labeled with γ- 32 P!ATP and T4 polynucleotide kinase. The oligomers corresponding to the amino acid sequences ##STR25## were made using an Applied Biosystems model 380A DNA synthesizer. Their sequences are as follows: ##STR26##
Duplicate nitrocellulose filter circles bearing plaques from 12 confluent 150 mm plates (approximately 50,000 pfu/plate) were hybridized at 45° C. overnight in a solution containing 6X SSC, 1X Denhardt's solution, 100 μg/ml yeast tRNA, 0.05% sodium pyrophosphate and 10 6 cpm/ml radiolabeled probe (>10 6 cpm per pmol). The filters were washed three times in 6X SSC at room temperature, followed by a higher-stringency 6X SSC wash at 100° C. below the minimum melting temperature of the oligomer probes, and exposed to x-ray film overnight.
A single 2.1 kb cDNA clone (designated pcGS-3:2.1) was isolated and sequenced. The amino acid sequence enclosed by the large ORF of this clone was identical to peptide sequences of the cGS-PDE purified from the supernatant fraction of a bovine heart homogenate. LeTrong et al., supra.
A second, amplified, bovine adrenal cortex cDNA library was screened using the ( 32 P)-labeled CGS-3:2.1 partial cDNA, yielding a 4.2 kb cDNA (designated 3CGS-5).
The library was constructed, amplified as in Maniatis et al., supra, plated and screened with the bovine cDNA insert from clone CGS-3:2.1. The probe was prepared using the method of Feinberg et al., supra, and the radiolabeled DNA was purified using Elutip-D® columns. Plaques (600,000 pfu on twelve 150 mm plates) bound to filter circles were hybridized at 42° C. overnight in a solution containing 50% formamide, 20 mM Tris-HCl (pH 7.5, 1X Denhardt's solution, 10% dextran sulfate, 0.11% SDS and 10 6 cpm/ml 32 P!-labeled probe (10 9 cpm/μg). The filters were washed three times for 15 minutes with 2X SSC/0.1% SDS at room temperature, followed by two 15-minute washes with 0.1X SSC/0.1% SDS at 45° C. The filters were exposed to x-ray film overnight. Ausubel et al., supra.
From this initial screening, 52 putative clones were identified. Twenty of these clones were randomly selected, purified by several rounds of re-plating and screening Maniatis et al., supra! and the insert cDNAS were subcloned into pBluescript SK(-) by in vivo excision Short et al., supra! as recommended by the manufacturer. Plasmid DNA prepared from these clones were analyzed by restriction analysis and/or sequencing. From this survey, a 4.2 kb cDNA representing the largest open reading frame was identified. The cDNA inserts from the other putative clones were shorter, and appeared to be identical based on the nucleotide sequence of the insert ends.
Putative CGS-PDE cDNAs were sequenced by a modification of the Sanger method Sanger et al., Proc.Natl.Acad.Sci. USA, 74:5463-5467! using Sequenase® or Taq Trak® kits as directed by the manufacturer. Templates were prepared from the cDNAs by constructing a series of nested deletions Henikoff, Gene, 28:351-359 (1984)! in the vector, pBluescript SK(-) (Stratagene) using exonuclease III and mung bean nuclease according to the manufacturer's protocol. In cases where overlapping templates were not attained by this method, the cDNAs were cleaved at convenient restriction endonuclease sites and subcloned into pBluescript, or specific oligomers were manufactured to prime the template for sequencing. Single-stranded DNA templates were rescued by isolating the DNA from phagemid secreted by helper phage-infected XL1 cells harboring the pBluescript plasmid Levinson et al., supra! as recommended by the manufacturer (Stratagene). Homology searches of GENBANK (Release 66.0), EMBL (Release 25.0), and NBRF nucleic acid (Release 36.0) and protein (Release 26.0) databases were conducted using Wordsearch, FASTA and TFASTA programs supplied with the Genetics Computer Group software package Devereux et al., Nuc.Acids Res., 12:387-395 (1984).
The nucleotide sequence and deduced amino acid sequence encoded by the large open reading frame of p3CGS-5 cDNA clone insert is provided in SEQ ID NO: 38 and SEQ ID NO: 39. Starting with the first methionine codon, the cDNA encodes a 921 residue polypeptide with a calculated molecular weight of about 103,000. Although no stop codons precede this sequence, an initiator methionine consensus sequence Kozak, J.Cell Biol., 108:229-241 (1989)! has been identified. The presence of 36 adenosine residues at the 3' end of the cDNA preceded by a transcription termination consensus sequence Birnstiel et al., Cell, 41:349-359 (1985)! suggests that all of the 3' untranslated sequence of the cGS-PDE mRNA is represented by this clone.
A putative phosphodiesterase-deficient (PPD) strain of S49 cells Bourne et al., J.Cell.Physiol., 85:611-620 (1975)! was transiently transfected with the cGS-PDE cDNA using the DEAE-dextran method. The cGS-PDE cDNA was ligated into the unique BamHI cloning site in a mammalian expression vector, designated pZEM 228, following a zinc-inducible metallothionine promoter and prior to an SV40 transcription termination sequence. The DNA was purified from large-scale plasmid preparations using Qiagen pack-500 colamns as directed by the manufacturer. PPD-S49 cells were cultured in DMEM containing 10% heat-inactivated horse serum, 50 μg/ml penicillin G and 50 μg/ml streptomycin sulfate at 37° C. in a water-saturated 7% CO 2 atmosphere. Prior to transfections, confluent 100 mm dishes of cells were replated at one-fifth of the original density and incubated for 24-36 h. In a typical transfection experiment, PPD-S49 cells (50-80% confluent) were washed with Tris-buffered-saline and approximately 2×10 7 cells were transfected with 10 μg of DNA mixed with 400 μg of DEAE-dextran in one ml of TBS. The cells were incubated at 37° C. for 1 hr with gentle agitation every 20 min. Next, DMSO was added to a final concentration of 10% and rapidly mixed by pipetting up and down. After 2 min, the cells were diluted with 15 volumes of TBS, collected by centrifugation, and washed, consecutively with TBS and DMEM. The cells were resuspended in complete medium and seeded into fresh 100 mm plates (1-2×107 cells/10 ml/plate). After 24 h, the cells were treated with TBS alone, or containing zinc sulfate (final concentration=125 μM) and incubated for an additional 24 h. The cells were harvested and washed once with TBS. The final cell pellets were resuspended in two mls of homogenization buffer (40 mM Tris-HCl; pH 7.5, 15 mM benzamidine, 15mM β-mercaptoethanol, 0.7 μg/ml pepstatin A, 0.5 μg/ml leupeptin and 5 mM EDTA) and disrupted on ice using a dounce homogenizer. The homogenates were centrifuged at 10,000×g for 5 min at 40° C. and the supernatants were assayed for phosphodiesterase activity and protein concentration.
cGS PDE activity was determined by a previously described method using 3 H!cAMP as the substrate as in Martins et al., J.Biol.Chem., 257:1973-1979 (1982). Phosphodiesterase assays where performed in triplicate. The Bradford assay Bradford, Anal. Biochem., 72:248-254 (1976)! was used to quantitate protein using BSA as the standard.
In the absence of zinc treatment, no increase in basal activity or cGMP-stimulated phosphodiesterase activity was detected in PPD S49 cells transfected with the cGS PDE-ZEM 228 construct or the vector alone. However, zinc-treated cells; transfected with cGS-PDE cDNA, but not the vector alone, expressed cGMP-enhanced cAMP phosphodiesterase activity indicating that the cDNA encodes a cGS-PDE. The total activity of the homogenates and 50,000×g supernatants was not significantly different.
Transient expression of the CGS-PDE cDNA in COS-7 cells was accomplished as in Example I. A 4.2 kb fragment of p3CGS-5 was isolated using HindIII and NotI and was inserted into plasmid pCDM8, which had been digested with the same enzymes. The character of products produced in COS-7 cells transformed with the p3CGS-5/pCDM8 construct is discussed in Example V, infra.
EXAMPLE V
Isolation, Purification, and Partial Sequence Determination of CGS-PDE cDNA from Bovine Brain
A. Isolation of Bovine Brain cGSPDE cDNA Clone. pBBCGSPDE-5
A bovine brain cDNA library constructed with the λ ZAP vector (kindly provided by Ronald E. Diehl, Merck, Sharp & Dohme) was screened with a 450 bp EcoRI/ApaI restriction endonuclease cleavage fragment of the p3CGS-5 cDNA corresponding to (p3CGS-5) nucleotide position numbers 1-452. The probe was prepared using the method of Feinberg et al., supra, and the 32 P!-labeled DNA was purified using Elutip D® columns. Plaques (a total of 600,000 plaques con 12-150 mm plates) bound to filter circles were hybridized at 42° overnight in a solution containing 50% formamide, 20 mM Tris HCl (pH 7.5), 1X Denhardt's solution, 10% dextran sulfate, 0.1% SDS and 10 6 cpm/ml 32 P!-labeled probe (10 9 cpm/μg). The filters were washed three times for 15 minutes with 2X SSC/0.1% at room temperature, followed by two 15 minute washes with 0.1X SSC/0.1% SDS at 45%. The filters were exposed to x-ray film overnight.
Forty putative clones were picked from this first screen, of which six were randomly selected and purified by several rounds of re-plating and screening Maniatis et al., supra!. The insert cDNAs were subcloned into pBluescript SK(-) by in vivo excision as recommended by the manufacturer. Plasmid DNA prepared from cultures of each clone was sequenced from the ends using Sequenase and Taq Trak sequencing kits. The sequence obtained from this experiment confirmed that the bovine brain cDNA clone, pBBCGSPDE-5 was a CGS-PDE cDNA, and that it was different than the adrenal cGS-PDE cDNA at the five-prime end.
Partial sequence analysis of the pBBCGSPDE-5 insert at its 5' end (encoding the amino terminal region of the protein) revealed the sense strand set out in SEQ ID NO: 40, while sequencing of the 3' end of the insert revealed the antisense sequence of SEQ ID NO: 41.
B. Isolation or Bovine Brain cGS-PDE cDNL Clone, pBBCGSPDE-7
Each of the forty putative clones selected from the first round of purification described above was spotted individually onto a lawn of host XL1 cells and incubated overnight at 370, The plaques were screened with a 370 bp PstI/SmaI restriction endonuclease cleavage fragment of the p3CGS-5 cDlA (corresponding p3CGS-5 nucleotide position numbers 2661-3034). The probe was prepared using the method of Feinberg et al., supra, and the 32 P!-labeled DNA was purified using Elutip-D® columns. Plaques bound to filter circles were hybridized at 42° overnight in a solution containing 50% formamide, 20 mM Tris-HCl (pH 7.5), 1X Denhardt's solution, 10% dextran sulfate, 0.1% SDS and 10 6 cpm/ml ( 32 P)-labeled probe (10 9 cpm/μg). The filters were washed three times for 15 minutes with 2X SSC/0.1% SDS at room temperature, followed by two 15-minute washes with 0.1X SSC/0.1% SDS at 45°. The filters were exposed to x-ray film overnight.
After several rounds of plating and rescreening, six putative clones were purified and sequenced from the ends. The sequence of the five-prime end of the cDNA clone pBBCGSPDE-7 was identical to clone pBBCGSPDE-5, but not the adrenal gland-derived clone, p3CGS-5. The sequence of the three-prime end of the pBBCGSPDE-7 cDNA clone was identical to the p3CGS-5 insert sequence.
Sequence analysis of the pBBCGSPDE-7 insert revealed the DNA sequence set out in SEQ ID NO: 42 and the amino acid sequence of SEQ. ID NO: 43.
The large open reading frame encodes a 942-residue polypeptide that is nearly identical to the adrenal gland CGS-PDE isozyme (921 residues). The difference in the primary structure of these two isozymes lies in the amino-terminal residues 1-46 of the brain cGS-PDE, and residues 1-25 of the adrenal cGS-PDE. The remaining carboxy-terminal residues of the brain and adrenal cGS-PDE are identical.
For transient expression in COS-7 cells, a 3.8 kb fragment of pBBCGSPDE-7 was isolated using HindIII and NotI and inserted into plasmid pCDM8 which had been cut with HindIII and NotI restriction endonucleases. The recombinant pBBCGSPDE-7/CDM8 construct was used to transiently transfect COS-7 cells. The properties of the pBBCGSPDE-7/CDM8 construct and the p3CGS-5/CDM8 construct prepared in Example IV products were subsequently compared. Membrane and supernatant fractions were prepared from extracts of transfected COS-7 cells and assayed for cGS-PDE activity. Both the pBBCGSPDE-7/CDM8 and p3CGS5/CDM8 plasmid constructs produced cGS-PDE activities in COS-7 cell extracts, and most of the activity was detected in the supernatant fractions.
However, a 10-fold greater percentage of total cGS-PDE activity was detected in membranes from COS-7 cell extracts transfected with the pBBCGSPDE-7/CDM8 construct than in membranes prepared from p3CGS-5/CDM8-transfected COS-7 cells. These results indicate that, relative to the adrenal cGS-PDE, the isozyme encoded by the pBBCGSPDE-7 cDNA preferentially associates with cellular membranes.
EXAMPLE VI
Use of CGS-PDE Bovine Adrenal cDNA to Obtain Human CGS-PDE cDNAs
Several human cDNA clones, homologous to a cDNA clone encoding the bovine cyclic GMP-stimulated phosphodiesterase, were isolated by hybridization using a nucleic acid probe derived from the bovine cDNA. A combination of sequence analysis and hybridization studies indicates that these human cDNA clones encompass an open reading frame corresponding to a human phosphodiesterase.
cDNA libraries were probed with DNA from plasmid p3CGS-5 which contains a 4.2-kb cDNA insert encoding the bovine cGS-PDE. This plasmid was digested with the restriction enzymes SmaI and EcoRI. The approximately 3.0 kb fragment derived from the cDNA insert was isolated and purified by agarose gel electrophoresis. This fragment contains the entire open reading-frame of the PDE. The fragment was labeled with radioactive nucleotides by random priming.
The cDNA libraries were plated on a 150 mm petri dishes at a density of approximately 50,000 plaques per plate. Duplicate nitrocellulose filter replicas were prepared. The radioactive nucleic acid probe was used for hybridization to the filters overnight at 42° C. in 50% formamide, 5x SSPE (0.9M NaCl, 0.05M NaH 2 PO 4 H 2 O, 0.04M NaOH, and 0.005M Na 2 EDTA 2 H 2 O), 0.5% SDS, 100 μg/ml salmon testes DNA, and 5x Denhardt's solution. The filters were washed initially at room temperature and subsequently at 65° C. in 2x SSC containing 0.1% SDS. Positive plaques were purified and their inserts were subcloned into an appropriate sequencing vector for DNA sequence analysis by standard techniques.
First, a λgt10 cDNA library prepared from human hippocampus mRNA (clontech, random and dT primed) was screened. Of the approximately 500,000 plaques examined, 33 hybridized to the probe. One of these phages was digested with EcoRI to remove the cDNA insert. This insert-containing EcoRI fragment was cloned into Bluescript KS that had been digested with EcoRI and then treated with calf intestine alkaline phosphatase. One product of this reaction was the plasmid pGSPDE9.2, which showed two major differences when compared to the bovine cGS-PDE cDNA. The 5'0.4 kb of the pGSPDE9.2 insert diverged from the bovine cDNA. Approximately 0.7 kb from the 5' end of the human cDNA there is a 0.7 kb region that diverges from the bovine cDNA. This region may be an intron. Twenty-five of the remaining hippocampus plaques that had hybridized to the bovine probe were examined by PCR, hybridization and/or sequencing. None were found to extend through the regions that differed between the bovine and human cDNAs.
Phages λ GSPDE7.1 and λ GSPDE7.4, two other phages from the hippocampus library, were digested with EcoRI and HindIII. Each yielded a 1.8-kb fragment that contains most of the cDNA insert and approximately 0.2-kb of phage lambda DNA. The λ DNA is present in the fragment because in each case one of the EcoRI sites that typically bracket a cDNA insert had been destroyed, possibly when the library was constructed. The EcoRI/HindIII fragments were cloned into Bluescript KS digested with EcoRI and HindIII. This procedure gave rise to the plasmids pGSPDE7.1 and pGSPDE7.4. The cDNA inserts encode DNA homologous to the 3' portion of the bovine phosphodiesterase cDNA. Both of the cDNA inserts in these clones begin at an,EcoRI site and the sequences are homologous adjacent this site.
Portions of pGSPDE7.1 and pGSPDE7.4 cDNA inserts were sequenced and are identical except for a short region of their 3' ends. The cDNA insert in pGSPDE7.1 ends with a sequence of approximately 70 adenine bases, while the cDNA insert in pGSPDE7.4 ends with three additional nucleotides not present in pGSPDE7.1 followed by a sequence of approximately 20 adenine bases.
Next, a cDNA library prepared in λ ZapII (Stratagene) from human heart mRNA yielded one hybridizing plaque from the approximately 500,000 screened. The Bluescript; SK(-) plasmid pGSPDE6.1 containing the hybridizing insert was excised in vivo from the λ ZapII clone. Sequence analysis showed that the insert is homologous to the bovine phosphodiesterase cDNA. The homologous reunion spans the position of the EcoRI found in the sequence formed by joining the sequence of the insert from pGSPDE9.2 to the sequence of the insert in pGSPDE7.1 or PGSPDE7.4. Thus, it is thought that the two clones from the hippocampus form a complete open reading frame.
A third λ gt10library derived from human placenta mRNA yielded five hybridizing plaques from approximately 800,000 screened. These placental cDNA clones were short and their sequences were identical to portions of the hippocampus cDNA pGSPDE9.2. Screening 5×10 5 plaques from U118 glioblastoma cDNA library, 5×10 5 from a spleen cDNA library and 5×10 5 from an adrenal library (Cushings Disease) gave no hybridization plaques.
Given the homology between the bulk of human and bovine cGS-PDE sequence, it was decided to obtain multiple independent cDNA clones containing the 5' end of the human cGS-PDE to determine if the 0.4 kb 5' sequence was an artifact. An approximately 0.95 kb EcoRI-HindII fragment from the 5' end of the bovine cGS cDNA plasmid p3cgs5 was random primed and used as a probe to screen a number of human cDNA libraries. Hippocampus library screening was carried out under the same screening conditions as described above. All remaining screenings were carried out as described with respect to human heart cDNA library screenings in Example VII, infra. No positives were obtained screening 5×10 5 plaques from a human T cell library (Hut78, dT-primed), 10 6 plaques from the hippocampus cDNA library (random and dT-primed), 5×10 5 plaques from a human liver cDNA library (dT-primed, 5' stretch, Clontech), 5×10 5 plaques from a human SW1088 glioblastoma cDNA library (dT-primed), 5×10 5 plaques from the same heart cDNA library (random and dT-primed), and 1.5×10 6 plaques from a human lung cDNA library (random primed). Two positives were obtained from screening 5×10 5 plaques from a human fetal brain cDNA library (random and dT-primed, Stratagene). These were designated as HFB9.1 and HFB9.2.
Bluescript SK(-) plasmids pHFB9.2 and pHFB9.1 were excised in vivo from the λZapII clones. DNA sequence analysis revealed that HFB9.1 starts about 80 nucleotides further 3' than does HFB9.2 and reads into an intron approximately 1.9 kb of the way into HFB9.2. HFB9.2 covers the entire open reading frame of the cGS-PDE, but reads into what may be an intron 59 nucleotides after the stop codon. Both of them lack the 5'0.4 kb and the presumed intron found in pGSPDE9.2. The entire open reading frame of HFB9.2 was isolated and assembled into yeast expression vector pBNY6N. The resulting plasmid, designated pHcgs6n, includes the coding region of the cDNA as an EcoRI/XhoI insert. DNA and deduced amino acid sequences for the insert are provided in SEQ.ID No: 44 and 45, respectively.
EXAMPLE VII
Use of CaM-PDE 61 kDa Bovine Brain cDNA to Obtain Human CaM-PDE 61 kDa cDNA
Human cDNA clones, λ CaM H6a and λ CaM H3a, which are homologous to the cDNA encoding the bovine 61 kDa CaM-PDE, were obtained by hybridization using a nucleic acid probe derived from the cDNA encoding the bovine species enzyme. A combination of sequence analysis and hybridization studies indicate that λ Cam H6a contains most of an open reading frame encoding a human CaM-PDE.
The hybridization probe used to isolate the human DNA was derived from first strand cDNA of bovine lung tissue by PCR treatment. More specifically the 23-mer oligonucleotide designated PCR-2S in Example I (see, SEQ ID NO: 1) was combined in a PCR reaction with bovine lung cDNA and a redundant antisense 23-mer oligonucleotide (PCR-5AS) based on the pCAM insert sequence with ##STR27## representing the amino acid sequence ##STR28## according to the general procedures of Examples I and III, to generate a 1098 bp cDNA fragment representing a large portion of the coding region of the pCAM-40 insert. The PCR products were purified on a 1% agarose gel using 0.4M Tris-acetate/0.001M EDTA buffer containing 0.5 μg/ml ethidium bromide. The DNA products were visualized with UV light, cleanly excised from the gel with a razor blade, purified using Geneclean II reagent kit and ligated into EcoRV-cut pBluescript vector DNA.
To determine if the PCR amplification products were CAM-PDE cDNAS, the subcloned PCR DNA products were sequenced from the ends using T3 and T7 promoter primers and either Sequenase or Taq Polymerase sequencing kits. Approximately 250 bases from each end of this DNA were then compared to the amino acid sequence of bovine CAM-PDE, confirming that the PCR DNA product was a partial CAM PDE cDNA. This clone was designated pCAM-1000 and contained a 1.1 -kb insert of nucleic acid that corresponds to nucleotides 409 to 1505 of the insert of pCAM-40. pCaM1000 was digested with the restriction enzymes HinDIII and BamHI. The 1.1 -kb fragment was purified by agarose gel electrophoresis and then digested with the restriction enzyme AccI. The two fragments were separated and purified by agarose gel electrophoresis. These separated fragments were labeled with radioactive nucleotides by random priming.
Human cDNA libraries were plated on 150 mm petri dishes at a density of approximately 50,000 plaques per dish and duplicate nitrocellulose filter replicas were prepared. Each probe was hybridized to a separate set of the duplicate filters. The filters were hybridized overnight at 65° C. in 3x SSC, 0.1% sarkosyl, 50 μg/ml salmon testes DNA, 10x Denhardt's solution, 20 mM sodium phosphate (pH 6.8). They were washed at 65° C. in 2x SSC containing 0.1% SDS.
A λ gt10 library prepared from human hippocampus mRNA yielded three hybridizing plaques of the approximately 500,000 screened. Of these three hybridizing plaques, two hybridized to both probes and the third hybridized to the longer of the two probes. The λ Cam H6a clone contains an approximately 2 kb insert that is homologous to the cDNA encoding the bovine clone of pCAM-40.
The λ cam H6a cDNA was subcloned into the plasmid Bluescript KS for sequence analysis. Although the cDNA library had been constructed with EcoRI linkers, one of the EcoRI sites that should have flanked the cDNA insert did not cut with EcoRI. Thus, the cDNA was subcloned as two fragments: an approximately 0.7 kb EcoRI/HindIII fragment (pcamH6C) and an approximately 1.6 kb HindIII fragment that contained approximately 1.3 kb of cDNA and 0.25 kb of flanking λgt10 vector DNA (pcamH6B). DNA sequence analysis revealed that it encoded most of a human CaM-PDE homologous to the bovine 61k CaM-PDE, except that the human cDNA appeared to be missing two base pairs in the middle of the coding region. These missing nucleotides correspond to positions 626 and 627 of the human cDNA sequence if it is aligned with the pCAM-40 bovine 61 kDa CaM-PDE (SEQ. ID NO: 5 for maximum homology.
Another of the cDNA clones from the hippocampus cDNA library that had been screened with the bovine 61 kDa CaM-PDE probes was λCamH2a. It contained an approximately 1.0 kb insert. As was the case for λCamH6a cDNA, only one of the two EcoRI sites that should be present-at the ends of the insert would cut. The original subcloning and DNA sequence analysis for this cDNA utilized PCR fragments generated with oligos in the flanking λgt10 vector arms. This cDNA overlaps much of the 5' end of the insert in λCamH6a and contained the additional two nucleotides predicted by the bovine sequence and required to maintain the PDE open reading frame. The λCamH2a insert also appeared to contain two introns; one 5' of the initiator methionine and one downstream of the HindIII site. The EcoRI/HindIII fragment from λCamH2a (corresponding to the region covered by pcamH6C) was subcloned into the plasmid Bluescript SK - and designated pcamH2A-16. This was then used as the source of the two additional bp in the construction of yeast expression plasmids described below.
Two different plasmids were constructed for human CaM-PDE expression in yeast. One plasmid, pHcam61-6N-7, contains the entire open reading frame. The second plasmid, pHcam61met140, starts at an internal methionine (beginning at nucleotide position 505) and extends to the end of the open reading frame. These expression plasmids were constructed by modifying the 3' portion of the open reading frame and then adding the two differently modified 5' ends to the 3' end. The sequence of the cDNA insert of pHcam61-6N-7 is set out in SEQ. ID NO: 48 and the deduced amino acid sequence of the CaM-PDE encoded thereby is set out in SEQ. ID NO: 49. During construction of the cDNA insert, the nucleotide at position 826 was altered from T to C, but the encoded amino acid was conserved. Plasmid pHcam61met140, as noted above, has a cDNA insert lacking the first 140 codons of the coding region of the pHcam61-6N-7 but is otherwise identical thereto.
A third cDNA, λcamH3a, contained an approximately 2.7 kb insert. This cDNA insert was subcloned for sequence analysis. Although the cDNA library had been constructed with EcoRI, the inserted cDNA in λCamH3a could not be excised with EcoRI.
Presumably one of the EcoRI sites was destroyed during the construction of the library. The cDNA insert was excised from the λ clone by digestion with HindIII and EcoRI. This digestion yields two relevant fragments, a 0.6 kb HindIII fragment which contains a portion of DNA from the left arm of λgt10 attached to the cDNA insert and an approximately 2.4 kb HindIII/EcoRI fragment containing the remainder of the cDNA insert. These two fragments were assembled in the plasmid Bluescript KS to yield an approximately 3 kb fragment. The orientation of the small HindIII fragment was the same as the original λ clone. This subclone is known as pcamH3EF. Although this cDNA hybridizes to the bovine probe from the bovine CaM-PDE 61 kDa cDNA, sequence analysis revealed that it appeared to be the product of a different CaM-PDE gene. Plasmid pcamH3EF contains what may be the entire open reading frame and would encode a protein approximately 75% homologous to the protein encoded by the insert of pHcam61-6N-7 over much of its lengths. DNA and deduced amino acid sequences are set out in SEQ. ID NOS: 50 and 51, respectively. The DNA sequence of the region between nucleotide 80 and 100 of pcamH3EF is uncertain. This area is 5' to the initiator methionine codon and thus does not effect the open reading frame.
An approximately 2.4 kb fragment of pcamH3EF was gel purified following digestion with the restriction enzymes HindIII and EcoRI. This fragment was used to screen additional human cDNA libraries in a similar manner to the screen described above. Screening approximately 5×10 5 plaques from a human heart cDNA library (Stratagene) yielded two plaques that hybridized to the pcamH3EF probe. The Bluescript SK 31 plasmid pcamHella was excised in vivo from one of these positive λZapII clones. DNA and deduced amino acid sequences for the cDNA insert are set out in SEQ. ID NO: 52 and 53, respectively. Sequence analysis of pcamHella showed that the insert began at nucleotide position 610 of pcamH3EF and was nearly identical through nucleotide position 2066, at which point the DNA sequence diverged from that of pcamH3EF. The cDNA insert of pcamHella continued for approximately 0.6 kb. The consequence of this divergence is to alter the carboxy terminus of the protein that would be encoded by the open reading frame within the cDNA. The pcamH3EF cDNA could encode a protein of 634 amino acids (MW72,207). Assuming the 5' end of the pcamHella cDNA is the same as that of the 5' end of pcamH3EF (5' to nucleotide position 610), pcamHella could encode a 709 amino acid protein (MW80,759). These divergent 3' ends may be the consequence of alternative splicing, lack of splicing, or unrelated DNA sequences being juxtaposed during the cloning process.
EXAMPLE VIII
Expression of Bovine and Human PDE cDNAs for Complementation of Yeast Phenotypic Defects
The present example relates to the expression of bovine and PDE clones in yeast demonstrating the capacity of functional PDE expression products to suppress the heat shock phenotype associated with mutation of yeast phosphodiesterase genes and also relates to the biochemical assay of expression products. The host cells used in these procedures were S. cerevisiae yeast strains 10DAB (ATCC accession No. 74049) and YKS45, both of which were pde 1- pde 2- resulting in a phenotype characterized by heat shock sensitivity, i.e., the inability of cells to survive exposure to elevated temperatures on the order of 55°-56° C. In these complementation procedures, the inserted gene product was noted to conspicuously modify the heat shock phenotype.
This capacity, in turn, demonstrates the feasibility of systems designed to assay chemical compounds for their ability to modify (and especially the ability to inhibit) the in vivo enzymatic activity of mammalian Ca 2+ /calmodulin stimulated and cGMP stimulated cyclic nucleotide phosphodiesterase.
A. Yeast Phenotype Complementation by Expression of a cDNA Encoding CaM-PDE
A 2.2 kb cDNA fragment, adapted for insertion into yeast expression plasmids pADNS (ATCC accession No. 68588) and pADANS (ATCC accession No. 68587) was derived from plasmid pCAM-40 (Example I) by polymerase chain reaction. Briefly, the following PCR amplification was employed to alter the pCAM-40 DNA insert to align it appropriately with the ADHl promoter in the vectors.
One oligonucleotide primer (Oligo A) used in the PCR reaction ##STR29## anneals to the pCaM-40 cDNA clone at base pair positions 100-116 and includes a HindIII site before the initial methionine codon. A second oligonucleotide primer (Oligo B) ##STR30## was designed to anneal at positions 520-538 and also includes a HindIII site two bases before a methionine codon. The third oligonucleotide ##STR31## annealed to a position in the plasmid that was 3' of the insert. For one reaction, Oligo A and oligo C were used as primers with pCAM-40 as the template. The nucleic acid product of this reaction included the entire open reading frame. A second reaction used Oligo B and Oligo C as primers on the template pCAM-40 and yielded a nucleic acid product that lacked the portion of the cDNA sequence encoding the calmodulin binding domain. These amplified products were digested with HindIII and NotI and ligated to HindIII/NotI-digested yeast expression vectors pADNS and pADANS. Plasmid clones containing inserts were selected and transformed into S. cerevisiae strain 10DAB by lithium acetate transformation.
Transformed yeast were streaked in patches on agar plates containing synthetic medium lacking the amino acid leucine (SC-leucine agar) and grown for 3 days at 30° C. Replicas of this agar plate were made with three types of agar plates: one replica on SC-leucine agar, one replica on room temperature YPD agar, and three replicas on YPD agar plates that had been warmed to 56° C. The three warmed plates were maintained at 56° C. for 10, 20, or 30 minutes. These replicas were than allowed to cool to room temperature and then all of the plates were placed at 30° C. Yeast transformed with plasmids constructed to express the CaM-PDE were resistant to the thermal pulse. More specifically, both the construct designed to express the complete open reading frame and that designed to express the truncated protein (including the catalytic region but not the calmodulin binding domain), in either pADNS or pADANS, complemented the heat shock sensitivity phenotype of the 10DAB host cells, i.e., rendered them resistant to the 56° C. temperature pulse.
In a like manner, plasmids pHcam61-6N-7 and pHcam61met140(Example VII) were transformed into yeast host 10DAB. Heat shock phenotypes were suppressed in both transformants.
B. Biochemical Assay of Expression Products
The bovine CaM-PDE expression product was also evaluated by preparing cell-free extracts from the 10DAB yeast cells and measuring the extracts' biochemical phosphodiesterase activity. For this purpose, 200 ml cultures of transformed yeast were grown in liquid SC-leucine to a density of about 6 million cells per ml. The cells were collected by centrifugation and the cell pellets were frozen. Extracts were prepared by thawing the frozen cells on ice, mixing the cells with 1 ml of PBS and an equal volume of glass beads, vortexing them to disrupt the yeast cells, and centrifuging the disrupted cells at approximately 12,000×g for 5 min to remove insoluble debris. The supernatant was assayed for phosphodiesterase activity.
Extracts of yeast cells, up to 50 μl, were assayed for phosphodiesterase activity in 50 mM Tris (pH 8.0), 1.0 mM EGTA, 0.01 mg/mL BSA (bovine serum albumin), 3 H!-cyclic nucleotide (4-10,000 cpm/pmol), and 5 mM MgCl 2 in a final volume of 250 al at 30° C. in 10×75 mm glass test tubes. The incubations were terminated by adding 250 μl of 0.5M sodium carbonate pH 9.3, 1M NaCl, and 0.1% SDS. The products of the phosphodiesterase reaction were separated from the cyclic nucleotide by chromatography on 8×33 mm columns of BioRad Affi-Gel 601 boronic acid gel. The columns were equilibrated with 0.25M sodium bicarbonate (pH 9.3) and 0.5M NaCl. The reactions were applied to the columns. The assay tubes were rinsed with 0.25M sodium bicarbonate (pH 9.3) and 0.5M NaCl and this rinse was applied to the columns.
The boronate columns were washed twice with 3.75 ml of 0.25M sodium bicarbonate (pH 9.3) and 0.5M NaCl followed by 0.5 ml of 50 mM sodium acetate (pH 4.5). The product was eluted with 2.5 ml of 50 mM sodium acetate (pH 4.5) containing 0.1M sorbitol and collected in scintillation vials. The eluate was mixed with 4.5 ml Ecolite Scintillation Cocktail and the radioactivity measured by liquid scintillation spectrometry.
Both the construct designed to express the complete bovine open reading frame and that designed to express a truncated protein, in either pADNS or pADANS, expressed active protein as determined by biochemical phosphodiesterase assay of cell extracts. Extracts of 10DAB harboring pcam61met140 yielded measurable phorphodiesterase activity (see, infra, second method of part D) while the extract of 10DAB cells harboring pcamH61-6N-7 lacked detectable activity.
C. Yeast Phenotype Complementation by Expression of a cDNA Encoding a cGS-PDE
The plasmid p3CGS-S, which contains a 4.2-kb DNA fragment encoding the bovine cGS-PDE, was adapted for cloning into pADNS and pADANS by replacing the first 147 bases of the cDNA with a restriction site suitable for use in insertion into plasmids. The oligonucleotide BS1, having the sequence ##STR32## encodes a HindIII site and anneals to positions 148-165 of the cDNA insert. An oligonucleotide designated BS3 ##STR33## anneals to positions 835-855 just 3' of a unique NsiI site. The resulting PCR-generated fragment following digestion with HindIII and NsiI was then ligated to HindIII- and NsiI-digested p3CGS-5 thereby replacing the original 5' end of the bovine cDNA. A plasmid derived from this ligation was digested with HindIII and NotI to release the modified cDNA insert. The insert was cloned into pADNS and pADANS at their HindIII and NotI sites. These plasmids were then transformed into the yeast strain 10DAB by the lithium acetate method and the transformed cells were grown and subjected to elevated temperatures as in Section A, above. Yeast transformed with plasmids constructed to express the bovine cGS-PDE were resistant to the thermal pulse.
In a like manner, plasmid pHcgs6n (Example VI) was transformed into yeast: host strain YKS45 by lithium acetate transformation. Heat shock analysis was performed as above except that the plates were initially grown two days at 30° C. and the warmed plates were maintained at 56° C. for 10, 20, 30 and 45 minutes. Yeast transformed with the plasmid designed to express the full length human cGS-PDE was resistant to thermal pulse.
D. Biochemical Assay of Expression Product
The expression of the bovine cGS-PDE was also evaluated by preparing cell-free extracts from the yeast and measuring the extracts' biochemical phosphodiesterase activity. For this purpose, 50 ml cultures of transformed 10DAB yeast cells were grown in liquid SC-leucine to a density of about 10 million cells per ml. Sherman et al., Methods in Yeast Genetics, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (1986). The cells were collected by centrifugation, the cell pellets were washed once with water, and the final cell pellets were frozen. To prepare an extract, the frozen cells were thawed on ice, mixed with 1 ml of PBS and an equal volume of glass beads, vortexed to disrupt the yeast cells, and centrifuged to remove debris. The supernatant was then assayed for phosphodiesterase activity as in Section B, above. Constructs in either pADNS or pADANS expressed active protein as determined by biochemical phosphodiesterase assay of cell extracts.
YKS45 transformed with plasmid pHcgs6n were grown in SC-leu medium to 1-2×10 7 cells/ml. The cells were harvested by centrifugation and the cell pellets were frozen. A frozen cell pellet, typically containing 10 10 cells, was mixed with lysis buffer (25 mM Tris HCl pH 8, 5 mM EDTA, 5 mM EGTA, 1 mM o-phenathroline, 0.5 mM AEBSF, 0.01 mg/mL pepstatin, 0.01 mg/mL leupeptin, 0.01 mg/mL aprotinin, 0.1% 2-mercaptoethanol) to bring the total volume to 2.5 ml. The mixture was thawed on ice and then added to an equal volume of glass beads. The cells were disrupted by cycles of vortexing and chilling on ice, then additional lysis buffer was mixed with the disrupted cells to bring the total lysis buffer added to 5 ml. The suspension was centrifuged for 5 min. at 12,000×g. The supernatant was removed and either assayed immediately or frozen rapidly in a dry ice ethanol bath and stored at -70° C.
Phosphodiesterase activity was assayed by mixing an aliquot of cell extract in (40 mM Tris-Cl pH 8.0, 1. mM EGTA, 0.1 mg/mL BSA) containing 5 mM MgCl 2 and radioactive substrate, incubating at 30° C. for up to 30 min. and terminating the reaction with stop buffer (0.1M ethanolamine pH 9.0, 0.5M ammonium sulfate, 10 mM EDTA, 0.05% SDS final concentration). The product was separated from the cyclic nucleotide substrate by chromatography on BioRad Affi-Gel 601. The sample was applied to a column containing approximately 0.25 ml of Affi-Gel 601 equilibrated in column buffer (0.1M ethanolamine pH 9.0 containing 0.5M ammonium sulfate). The column was washed five times with 0.5 ml of column buffer. The product was eluted with four 0.5 ml aliquots of 0.25M acetic acid and mixed with 5 ml Ecolume (ICN Biochemicals). The radioactive product was measured by scintillation counting. Extracts from yeast expressing the human cGS-PDE hydrolyzed both cyclic AMP and cyclic GMP, as expected for this isozyme.
EXAMPLE IX
Tissue Expression Studies Involving CaM-PDE and CGS-PDE Polynuleotides
A. Northern Blot Analysis
DNAs isolated in Examples I, III, and IV above were employed to develop probes for screening total or poly A-selected RNAs isolated from a variety of tissues and the results are summarized below.
1. Northern analysis was performed on mRNA prepared from a variety of bovine adrenal cortex, adrenal medulla, heart, aorta, cerebral cortex, basal ganglia, hippocampus, cerebellum, medulla/spinal cord, liver, kidney cortex, kidney medulla, kidney papillae, trachea, lung, spleen and T-lymphocyte tissues using an approximately 3 kb radiolabeled cDNA fragment isolated from plasmid p3CGS-5 upon digestion with EcoRI and SmaI. A single 4.5 kb mRNA species-was detected in most tissues. The size of the CGS-PDE E WA appeared to be slightly larger (approximately 4.6 kb) in RNA isolated from cerebral cortex, basal ganglia and hippocampus. The cGS PDE mRNA was most abundant in adrenal cortex. It was also abundant in adrenal medulla and heart. It appeared to be differentially expressed in anatomically distinct regions of the brain and kidney. Among RNAs isolated from five different brain regions, cGS PDE mRNA was most abundant in hippocampus, cerebral cortex, and basal ganglia. Very little cGS PDE transcript was detected in cerebellum or medulla and spinal cord RNAs. Although the cGS PDE mRNA was detected in all regions of the kidney, it appeared to be most abundant in the outer red medulla and papillae. The cGS PDE mRNA was also detected in liver, trachea, lung, spleen, and T-lymphocyte RNA. Very little cGS PDE mRNA was detected in RNA isolated from aorta.
2. Radiolabeled DNA probes were prepared from random hexamer primed fragments extended on heat denatured 1.6 kb EcoRI restriction endonuclease fragments of the cDNA insert of plasmid pCAM-40. In Northern analysis, the DNA probes hybridized with 3.8 and 4.4 kb mRNAs in brain and most of the other tissues analyzed including cerebral cortex, basal ganglia, hippocampus, cerebellum, medulla and spinal cord, heart, aorta, kidney medulla, kidney papillae, and lung. Hybridization of probe with the 3.8 kb mRNA from liver, kidney cortex and trachea was only detected after longer autoradiographic exposure.
3. Northern blot analysis of mRNA from several tissues of the central nervous system was carried out using a subcloned, labeled p12.3a DNA fragment (containing most of the conserved PDE catalytic domain) as a probe. The most intense hybridization signal was seen in mRNA from the basal ganglia and strong signals were also seen in mRNA from other tissues including kidney papilla and adrenal medulla.
B. RNAse Protection
1. Three antisense riboprobes were constructed. Probe III corresponds to the catalytic domain-encoding region of p3cGS-5 (273 bp corresponding to bases 2393 through 2666 of SEQ. ID NO: 38); probe II to the cGMP-binding domain encoding (468 bp corresponding to bases 959 through 1426; and probe I to the 5' end and portions of amino terminal-encoding region (457 bases corresponding to bases 1 through 457).
Total RNAs extracted from all of the examined tissues completely protected probes II and III. Nearly complete protection (457 bases) of riboprobe I with RNAs isolated from adrenal cortex, adrenal medulla, and liver was also observed. However, RNA isolated from cerebral cortex, basal ganglia, and hippocampus only protected an approximately 268-base fragment of riboprobe I. A relatively small amount of partially protected probe I identical in size with the major fragments observed in the brain RNA samples was also detected in RNAs isolated from all of the examined tissues except liver. Interestingly, heart RNA yielded both completely protected (457 base) riboprobe and, like brain RNA, a 268-base fragment. Unlike the protection pattern observed using RNAs isolated from any of the other tissues, however, the partially protected riboprobe I fragment appeared to be more abundant. The results suggest that two different cGS-PDE RNA species are expressed.
2. Radiolabeled antisense riboprobes corresponding to a portion of either the CaM-binding domain on the catalytic domain of CaM-PDE were constructed from restriction endonuclease cleavage fragments (AccI/SstI and Tth111I/HincII) of pCAM-40cDNA. Total RNAs isolated from five different brain regions (cerebral cortex, basal ganglia, hippocampus, cerebellum, and medulla/spinal cord) completely protected the antisense riboprobes encoding both the CaM-binding and catalytic domains. Total RNAs from heart, aorta, lung, trachea and kidney completely protected the riboprobe corresponding to the catalytic domain but only protected about 150 bases of the CaM-binding domain riboprobe, suggesting that an isoform structurally related to the 61kD CaM-PDE is expressed in these tissues.
3. Antisense riboprobes were generated based on plasmid p12.3a and corresponding to bases -1 through 363 and 883-1278 of SEQ. II) NO: 26. The former probe included 113 bases of the 5' noncoding sequence as well as the start methionine cordon through the putative CaM-binding domain, while the latter encoded the catalytic domain. Among all tissues assayed, RNA from basal ganglia most strongly protected each probe. Strong signals of a size corresponding to the probe representing the amino terminus were observed in protection by cerebral cortex, cerebellum, basal ganglia, hippocampus and adrenal medulla RNA. No protection was afforded to this probe by kidney papilla or testis RNA even though the tissue showed signals on the Northern analysis and RNAse protection of the conserved domain probe, suggesting that a structurally related isozyme is expressed in this tissue.
While the present invention has been described in terms of specific methods and compositions, it is understood that variations; and modifications will occur to those skilled in the art upon consideration of the invention. Consequently only such limitations as appear in the appended claims should be placed thereon. Accordingly, it is intended in the appended claims to cover all such equivalent variations which come within the scope of the invention as claimed.
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 58(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 20 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:AARATGGGNATGAARAARAA20(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 8 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:LysMetGlyMetMetLysLysLys15(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 23 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:ACRTTCATYTCYTCYTCYTGCAT23(2) INFORMATION FOR SEQ ID NO:4:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 8 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:MetGlnGluGluGluMetAsnVal15(2) INFORMATION FOR SEQ ID NO:5:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2291 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 100..1689(xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:GGCTCAGAAACTGTAGGAATTCTGATGTGCTTCGGTGCATGGAACAGTAACAGATGAGCT60GCTTTGGGGAGAGCTGGAACGCTCAGTCGGAGTATCATCATGGGGTCTACTGCT114MetGlySerThrAla15ACAGAAACTGAAGAACTGGAAAACACTACTTTTAAGTATCTCATTGGA162ThrGluThrGluGluLeuGluAsnThrThrPheLysTyrLeuIleGly101520GAACAGACTGAAAAAATGTGGCAACGCCTGAAAGGAATACTAAGATGC210GluGlnThrGluLysMetTrpGlnArgLeuLysGlyIleLeuArgCys253035TTAGTGAAGCAGCTGGAAAAAGGTGATGTTAACGTCATCGACTTAAAG258LeuValLysGlnLeuGluLysGlyAspValAsnValIleAspLeuLys404550AAGAATATTGAATATGCAGCATCTGTGTTGGAAGCAGTTTATATTGAT306LysAsnIleGluTyrAlaAlaSerValLeuGluAlaValTyrIleAsp556065GAAACAAGGAGACTGCTGGACACCGATGATGAGCTCAGTGACATTCAG354GluThrArgArgLeuLeuAspThrAspAspGluLeuSerAspIleGln70758085TCGGATTCCGTCCCATCAGAAGTCCGGGACTGGTTGGCTTCTACCTTT402SerAspSerValProSerGluValArgAspTrpLeuAlaSerThrPhe9095100ACACGGAAAATGGGGATGATGAAAAAGAAATCTGAGGAAAAACCAAGA450ThrArgLysMetGlyMetMetLysLysLysSerGluGluLysProArg105110115TTTCGGAGCATTGTGCATGTTGTTCAAGCTGGAATTTTTGTGGAAAGA498PheArgSerIleValHisValValGlnAlaGlyIlePheValGluArg120125130ATGTACAGAAAGTCCTATCACATGGTTGGCTTGGCATATCCAGAGGCT546MetTyrArgLysSerTyrHisMetValGlyLeuAlaTyrProGluAla135140145GTCATAGTAACATTAAAGGATGTTGATAAATGGTCTTTTGATGTATTT594ValIleValThrLeuLysAspValAspLysTrpSerPheAspValPhe150155160165GCCTTGAATGAAGCAAGTGGAGAACACAGTCTGAAGTTTATGATTTAT642AlaLeuAsnGluAlaSerGlyGluHisSerLeuLysPheMetIleTyr170175180GAACTATTCACCAGATATGATCTTATCAACCGTTTCAAGATTCCTGTT690GluLeuPheThrArgTyrAspLeuIleAsnArgPheLysIleProVal185190195TCTTGCCTAATTGCCTTTGCAGAAGCTCTAGAAGTTGGTTACAGCAAG738SerCysLeuIleAlaPheAlaGluAlaLeuGluValGlyTyrSerLys200205210TACAAAAATCCATACCACAATTTGATTCATGCAGCTGATGTCACTCAA786TyrLysAsnProTyrHisAsnLeuIleHisAlaAlaAspValThrGln215220225ACTGTGCATTACATAATGCTTCATACAGGTATCATGCACTGGCTCACT834ThrValHisTyrIleMetLeuHisThrGlyIleMetHisTrpLeuThr230235240245GAACTGGAAATTTTAGCAATGGTCTTTGCCGCTGCCATTCATGACTAT882GluLeuGluIleLeuAlaMetValPheAlaAlaAlaIleHisAspTyr250255260GAGCATACAGGGACTACAAACAATTTTCACATTCAGACAAGGTCAGAT930GluHisThrGlyThrThrAsnAsnPheHisIleGlnThrArgSerAsp265270275GTTGCCATTTTGTATAATGATCGCTCTGTCCTTGAAAATCATCATGTG978ValAlaIleLeuTyrAsnAspArgSerValLeuGluAsnHisHisVal280285290AGTGCAGCTTATCGCCTTATGCAAGAAGAAGAAATGAATGTCCTGATA1026SerAlaAlaTyrArgLeuMetGlnGluGluGluMetAsnValLeuIle295300305AATTTATCCAAAGATGACTGGAGGGATCTTCGGAACCTAGTGATTGAA1074AsnLeuSerLysAspAspTrpArgAspLeuArgAsnLeuValIleGlu310315320325ATGGTGTTGTCTACAGACATGTCGGGTCACTTCCAGCAAATTAAAAAT1122MetValLeuSerThrAspMetSerGlyHisPheGlnGlnIleLysAsn330335340ATAAGAAATAGTTTGCAGCAACCTGAAGGGCTTGACAAAGCCAAAACC1170IleArgAsnSerLeuGlnGlnProGluGlyLeuAspLysAlaLysThr345350355ATGTCCCTGATTCTCCATGCAGCAGACATCAGTCACCCAGCCAAATCC1218MetSerLeuIleLeuHisAlaAlaAspIleSerHisProAlaLysSer360365370TGGAAGCTGCACCACCGATGGACCATGGCCCTAATGGAGGAGTTTTTC1266TrpLysLeuHisHisArgTrpThrMetAlaLeuMetGluGluPhePhe375380385CTACAGGGAGATAAAGAAGCTGAATTAGGGCTTCCATTTTCCCCGCTT1314LeuGlnGlyAspLysGluAlaGluLeuGlyLeuProPheSerProLeu390395400405TGCGATCGGAAGTCAACGATGGTGGCCCAGTCCCAAATAGGTTTCATT1362CysAspArgLysSerThrMetValAlaGlnSerGlnIleGlyPheIle410415420GATTTCATAGTAGAACCAACATTTTCTCTTCTGACAGACTCAACAGAG1410AspPheIleValGluProThrPheSerLeuLeuThrAspSerThrGlu425430435AAAATTATTATTCCTCTTATAGAGGAAGACTCGAAAACCAAAACTCCT1458LysIleIleIleProLeuIleGluGluAspSerLysThrLysThrPro440445450TCCTATGGAGCAAGCAGACGATCAAATATGAAAGGCACCACCAATGAT1506SerTyrGlyAlaSerArgArgSerAsnMetLysGlyThrThrAsnAsp455460465GGAACCTACTCCCCCGACTACTCCCTTGCCAGCGTGGACCTGAAGAGC1554GlyThrTyrSerProAspTyrSerLeuAlaSerValAspLeuLysSer470475480485TTCAAAAACAGCCTGGTGGACATCATCCAGCAGAACAAAGAGAGGTGG1602PheLysAsnSerLeuValAspIleIleGlnGlnAsnLysGluArgTrp490495500AAAGAGTTAGCTGCTCAAGGTGAACCTGATCCCCATAAGAACTCAGAT1650LysGluLeuAlaAlaGlnGlyGluProAspProHisLysAsnSerAsp505510515CTAGTAAATGCTGAAGAAAAACATGCTGAAACACATTCATAGGTCTGAA1699LeuValAsnAlaGluGluLysHisAlaGluThrHisSer520525530ACACCTGAAAGACGTCTTTCATTCTAAGGATGGGAGGAAACAAATTCACAAGAAATCATG1759AAGACATATAAAAGCTACATATGCATAAAAAACTCTGAATTCAGGTCCCCATGGCTGTCA1819CAAATGAATGAACAGAACTCCCAACCCCGCCTTTTTTTAATATAATGAAAGTGCCTTAGC1879ATGGTTGCAGCTGTCACCACTACAGTGTTTTACAGACGGTTTCTACTGAGCATCACAATA1939AAGAGAATCTTGCATTACAAAAAAAAGAAAAAAATGTGGCTCGCTTTTAAGATGAAGCAT1999TTCCCAGTATTTCTGAGTCAGTTGTAAGATTCTTTAATCGATACTAATAGTTTCACTAAT2059AGCCACTGTCAGTGTCACGCACTGTGATGAAATCTTATACTTAGTCCTTCAACAGTTCCA2119GAGTTGTGACTGTGCTTAATAGTTTGCATATGAATTCTGGATAGAAATCAAATCACAAAC2179TGCATAGAAATTTTAAAAACCAGCTCCATATTAAATTTTTTTAAGATATTGTCTTGTATT2239GAAACTCCAATACTTTGGCCACCTGATGCAAAGAGCTGACTCATTTGAAACC2291(2) INFORMATION FOR SEQ ID NO:6:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 530 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:MetGlySerThrAlaThrGluThrGluGluLeuGluAsnThrThrPhe151015LysTyrLeuIleGlyGluGlnThrGluLysMetTrpGlnArgLeuLys202530GlyIleLeuArgCysLeuValLysGlnLeuGluLysGlyAspValAsn354045ValIleAspLeuLysLysAsnIleGluTyrAlaAlaSerValLeuGlu505560AlaValTyrIleAspGluThrArgArgLeuLeuAspThrAspAspGlu65707580LeuSerAspIleGlnSerAspSerValProSerGluValArgAspTrp859095LeuAlaSerThrPheThrArgLysMetGlyMetMetLysLysLysSer100105110GluGluLysProArgPheArgSerIleValHisValValGlnAlaGly115120125IlePheValGluArgMetTyrArgLysSerTyrHisMetValGlyLeu130135140AlaTyrProGluAlaValIleValThrLeuLysAspValAspLysTrp145150155160SerPheAspValPheAlaLeuAsnGluAlaSerGlyGluHisSerLeu165170175LysPheMetIleTyrGluLeuPheThrArgTyrAspLeuIleAsnArg180185190PheLysIleProValSerCysLeuIleAlaPheAlaGluAlaLeuGlu195200205ValGlyTyrSerLysTyrLysAsnProTyrHisAsnLeuIleHisAla210215220AlaAspValThrGlnThrValHisTyrIleMetLeuHisThrGlyIle225230235240MetHisTrpLeuThrGluLeuGluIleLeuAlaMetValPheAlaAla245250255AlaIleHisAspTyrGluHisThrGlyThrThrAsnAsnPheHisIle260265270GlnThrArgSerAspValAlaIleLeuTyrAsnAspArgSerValLeu275280285GluAsnHisHisValSerAlaAlaTyrArgLeuMetGlnGluGluGlu290295300MetAsnValLeuIleAsnLeuSerLysAspAspTrpArgAspLeuArg305310315320AsnLeuValIleGluMetValLeuSerThrAspMetSerGlyHisPhe325330335GlnGlnIleLysAsnIleArgAsnSerLeuGlnGlnProGluGlyLeu340345350AspLysAlaLysThrMetSerLeuIleLeuHisAlaAlaAspIleSer355360365HisProAlaLysSerTrpLysLeuHisHisArgTrpThrMetAlaLeu370375380MetGluGluPhePheLeuGlnGlyAspLysGluAlaGluLeuGlyLeu385390395400ProPheSerProLeuCysAspArgLysSerThrMetValAlaGlnSer405410415GlnIleGlyPheIleAspPheIleValGluProThrPheSerLeuLeu420425430ThrAspSerThrGluLysIleIleIleProLeuIleGluGluAspSer435440445LysThrLysThrProSerTyrGlyAlaSerArgArgSerAsnMetLys450455460GlyThrThrAsnAspGlyThrTyrSerProAspTyrSerLeuAlaSer465470475480ValAspLeuLysSerPheLysAsnSerLeuValAspIleIleGlnGln485490495AsnLysGluArgTrpLysGluLeuAlaAlaGlnGlyGluProAspPro500505510HisLysAsnSerAspLeuValAsnAlaGluGluLysHisAlaGluThr515520525HisSer530(2) INFORMATION FOR SEQ ID NO:7:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 7 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:MetAspAspHisValThrIle15(2) INFORMATION FOR SEQ ID NO:8:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 20 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:8:ATGAGRAGRCAYGTHACNAT20(2) INFORMATION FOR SEQ ID NO:9:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 7 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:9:LeuArgCysLeuValLysGln15(2) INFORMATION FOR SEQ ID NO:10:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 21 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(iv) ANTI-SENSE: YES(xi) SEQUENCE DESCRIPTION: SEQ ID NO:10:CTGCTTCACTAAGCATCTTAG21(2) INFORMATION FOR SEQ ID NO:11:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 75 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:11:ATGAGAAGGCACGTAACGATCAGGAGGAAACATCTCCAAAGACCCATCTTTAGACTAAGA60TGCTTAGTGAAGCAG75(2) INFORMATION FOR SEQ ID NO:12:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 21 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:12:ATGGAYGAYCACGTAACGATC21(2) INFORMATION FOR SEQ ID NO:13:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 21 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(iv) ANTI-SENSE: YES(xi) SEQUENCE DESCRIPTION: SEQ ID NO:13:AAGTATCTCATTGGAGAACAG21(2) INFORMATION FOR SEQ ID NO:14:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 54 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:14:ATGGATGATCACGTAACGATCAGGAGGAAACATCTCCAAAGACCCATCTTTAGA54(2) INFORMATION FOR SEQ ID NO:15:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 18 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:15:MetAspAspHisValThrIleArgArgLysHisLeuGlnArgProIle151015PheArg(2) INFORMATION FOR SEQ ID NO:16:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2656 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 136..1677(xi) SEQUENCE DESCRIPTION: SEQ ID NO:16:TTGCTGTCGAGAGAAAGAGGAAACTACTTTTGCCTTCTGGGCTCCTTGCAGGACAATAGA60TCAGGATAAGCTTCCACATTCTCTCCCTGGATTTCTGGAGTGGTTTCCAGGAACAAGCTA120AACTTTCACCTTTAAATGGATGACCATGTCACAATCAGGAGGAAACATCTC171MetAspAspHisValThrIleArgArgLysHisLeu1510CAAAGACCCATCTTTAGACTAAGATGCTTAGTGAAGCAGCTGGAAAAA219GlnArgProIlePheArgLeuArgCysLeuValLysGlnLeuGluLys152025GGTGATGTTAACGTCATCGACTTAAAGAAGAATATTGAATATGCAGCA267GlyAspValAsnValIleAspLeuLysLysAsnIleGluTyrAlaAla303540TCTGTGTTGGAAGCAGTTTATATTGATGAAACAAGGAGACTGCTGGAC315SerValLeuGluAlaValTyrIleAspGluThrArgArgLeuLeuAsp45505560ACCGATGATGAGCTCAGTGACATTCAGTCGGATTCCGTCCCATCAGAA363ThrAspAspGluLeuSerAspIleGlnSerAspSerValProSerGlu657075GTCCGGGACTGGTTGGCTTCTACCTTTACACGGAAAATGGGGATGATG411ValArgAspTrpLeuAlaSerThrPheThrArgLysMetGlyMetMet808590AAAAAGAAATCTGAGGAAAAACCAAGATTTCGGAGCATTGTGCATGTT459LysLysLysSerGluGluLysProArgPheArgSerIleValHisVal95100105GTTCAAGCTGGAATTTTTGTGGAAAGAATGTACAGAAAGTCCTATCAC507ValGlnAlaGlyIlePheValGluArgMetTyrArgLysSerTyrHis110115120ATGGTTGGCTTGGCATATCCAGAGGCTGTCATAGTAACATTAAAGGAT555MetValGlyLeuAlaTyrProGluAlaValIleValThrLeuLysAsp125130135140GTTGATAAATGGTCTTTTGATGTATTTGCCTTGAATGAAGCAAGTGGA603ValAspLysTrpSerPheAspValPheAlaLeuAsnGluAlaSerGly145150155GAACACAGTCTGAAGTTTATGATTTATGAACTATTCACCAGATATGAT651GluHisSerLeuLysPheMetIleTyrGluLeuPheThrArgTyrAsp160165170CTTATCAACCGTTTCAAGATTCCTGTTTCTTGCCTAATTGCCTTTGCA699LeuIleAsnArgPheLysIleProValSerCysLeuIleAlaPheAla175180185GAAGCTCTAGAAGTTGGTTACAGCAAGTACAAAAATCCATACCACAAT747GluAlaLeuGluValGlyTyrSerLysTyrLysAsnProTyrHisAsn190195200TTGATTCATGCAGCTGATGTCACTCAAACTGTGCATTACATAATGCTT795LeuIleHisAlaAlaAspValThrGlnThrValHisTyrIleMetLeu205210215220CATACAGGTATCATGCACTGGCTCACTGAACTGGAAATTTTAGCAATG843HisThrGlyIleMetHisTrpLeuThrGluLeuGluIleLeuAlaMet225230235GTCTTTGCCGCTGCCATTCATGACTATGAGCATACAGGGACTACAAAC891ValPheAlaAlaAlaIleHisAspTyrGluHisThrGlyThrThrAsn240245250AATTTTCACATTCAGACAAGGTCAGATGTTGCCATTTTGTATAATGAT939AsnPheHisIleGlnThrArgSerAspValAlaIleLeuTyrAsnAsp255260265CGCTCTGTCCTTGAAAATCATCATGTGAGTGCAGCTTATCGCCTTATG987ArgSerValLeuGluAsnHisHisValSerAlaAlaTyrArgLeuMet270275280CAAGAAGAAGAAATGAATGTCCTGATAAATTTATCCAAAGATGACTGG1035GlnGluGluGluMetAsnValLeuIleAsnLeuSerLysAspAspTrp285290295300AGGGATCTTCGGAACCTAGTGATTGAAATGGTGTTGTCTACAGACATG1083ArgAspLeuArgAsnLeuValIleGluMetValLeuSerThrAspMet305310315TCGGGTCACTTCCAGCAAATTAAAAATATAAGAAATAGTTTGCAGCAA1131SerGlyHisPheGlnGlnIleLysAsnIleArgAsnSerLeuGlnGln320325330CCTGAAGGGCTTGACAAAGCCAAAACCATGTCCCTGATTCTCCATGCA1179ProGluGlyLeuAspLysAlaLysThrMetSerLeuIleLeuHisAla335340345GCAGACATCAGTCACCCAGCCAAATCCTGGAAGCTGCACCACCGATGG1227AlaAspIleSerHisProAlaLysSerTrpLysLeuHisHisArgTrp350355360ACCATGGCCCTAATGGAGGAGTTTTTCCTACAGGGAGATAAAGAAGCT1275ThrMetAlaLeuMetGluGluPhePheLeuGlnGlyAspLysGluAla365370375380GAATTAGGGCTTCCATTTTCCCCGCTTTGCGATCGGAAGTCAACGATG1323GluLeuGlyLeuProPheSerProLeuCysAspArgLysSerThrMet385390395GTGGCCCAGTCCCAAATAGGTTTCATTGATTTCATAGTAGAACCAACA1371ValAlaGlnSerGlnIleGlyPheIleAspPheIleValGluProThr400405410TTTTCTCTTCTGACAGACTCAACAGAGAAAATTATTATTCCTCTTATA1419PheSerLeuLeuThrAspSerThrGluLysIleIleIleProLeuIle415420425GAGGAAGACTCGAAAACCAAAACTCCTTCCTATGGAGCAAGCAGACGA1467GluGluAspSerLysThrLysThrProSerTyrGlyAlaSerArgArg430435440TCAAATATGAAAGGCACCACCAATGATGGAACCTACTCCCCCGACTAC1515SerAsnMetLysGlyThrThrAsnAspGlyThrTyrSerProAspTyr445450455460TCCCTTGCCAGCGTGGACCTGAAGAGCTTCAAAAACAGCCTGGTGGAC1563SerLeuAlaSerValAspLeuLysSerPheLysAsnSerLeuValAsp465470475ATCATCCAGCAGAACAAAGAGAGGTGGAAAGAGTTAGCTGCTCAAGGT1611IleIleGlnGlnAsnLysGluArgTrpLysGluLeuAlaAlaGlnGly480485490GAACCTGATCCCCATAAGAACTCAGATCTAGTAAATGCTGAAGAAAAA1659GluProAspProHisLysAsnSerAspLeuValAsnAlaGluGluLys495500505CATGCTGAAACACATTCATAGGTCTGAAACACCTGAAAGACGTCTTTC1707HisAlaGluThrHisSer510ATTCTAAGGATGGGAGAGTGCTGTAACTACAAAACTTTCAAGCTTCTAAGTAAAAGGAAA1767GCAAAAACAAAATTACAGAAAAATATTTTTGCAGCTCTGAGGCTATTTAGATTGTCCTTG1827TTGTTTTAAATACATGGGAACCAAGTGAGAAGAGGGGCTGCTCAGAAGTTGTAGTCGAAG1887TCCTAAGACAACAATGAAGCATCAGAGCCCTGACTCTGTGACCTGATGAACTCTTCGTTG1947TAACTCTCAAGCTGGGAAACCACAGCGAATCCTGTTCCTGAAAGCAGTGAACCAGCCTGC2007ATCCACCACTGTTATTGCAAAGCACGAAAGCATCACCCACGTGGGGGTCATCACAATGCA2067AGTCACGCAAGACCTATGACCAAGATGACAAGAACCTCCAGCCCTTGTTGGAGACAGACA2127CTAGAACTGAGAGTGGGATTTGCCTTCTGGGGTGTTAATCCCATCAGGATGTAACAAAAT2187ATATTACAGGTCAAGGGATAAGGGACAAGAAGTGTGTGTCTGTGTGTGTGTGTGTGTATG2247TGCGCGCACTCAAAAATGTCTGTGAAAATGGAAGCCCACACTCTTCTGCACAGAGAGCAT2307TATTTGATGTGATTTATAATTTTACTACAAACAAACGAACTGCAGCCATTGGAGACTGCT2367TCCTTGTCATGTTTTGCCTGAGCATGTGCAGAGCCTTGCCTTTGTTCCAAATTGAAGAAC2427TACCTTTATTTGTTATTAGCTGCCAAGAAAGGTCAAGCCCAAGTAGGTGTTGTCATTTTC2487ACCGTACAAACTCTTCAATGATTGTTAGACTAAAGGAATTTGTTTTTGTGAAAGGTAGAA2547ATTAGATGGAAAAGATCAAGAGTAGTCATCAATTAAAGAAGAAAGTGAAGGTGGATATGT2607CCATCCTAATGAGTTTTCTGTTGCACCTGCTTCTTCCCTGCGACAGCAA2656(2) INFORMATION FOR SEQ ID NO:17:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 514 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:17:MetAspAspHisValThrIleArgArgLysHisLeuGlnArgProIle151015PheArgLeuArgCysLeuValLysGlnLeuGluLysGlyAspValAsn202530ValIleAspLeuLysLysAsnIleGluTyrAlaAlaSerValLeuGlu354045AlaValTyrIleAspGluThrArgArgLeuLeuAspThrAspAspGlu505560LeuSerAspIleGlnSerAspSerValProSerGluValArgAspTrp65707580LeuAlaSerThrPheThrArgLysMetGlyMetMetLysLysLysSer859095GluGluLysProArgPheArgSerIleValHisValValGlnAlaGly100105110IlePheValGluArgMetTyrArgLysSerTyrHisMetValGlyLeu115120125AlaTyrProGluAlaValIleValThrLeuLysAspValAspLysTrp130135140SerPheAspValPheAlaLeuAsnGluAlaSerGlyGluHisSerLeu145150155160LysPheMetIleTyrGluLeuPheThrArgTyrAspLeuIleAsnArg165170175PheLysIleProValSerCysLeuIleAlaPheAlaGluAlaLeuGlu180185190ValGlyTyrSerLysTyrLysAsnProTyrHisAsnLeuIleHisAla195200205AlaAspValThrGlnThrValHisTyrIleMetLeuHisThrGlyIle210215220MetHisTrpLeuThrGluLeuGluIleLeuAlaMetValPheAlaAla225230235240AlaIleHisAspTyrGluHisThrGlyThrThrAsnAsnPheHisIle245250255GlnThrArgSerAspValAlaIleLeuTyrAsnAspArgSerValLeu260265270GluAsnHisHisValSerAlaAlaTyrArgLeuMetGlnGluGluGlu275280285MetAsnValLeuIleAsnLeuSerLysAspAspTrpArgAspLeuArg290295300AsnLeuValIleGluMetValLeuSerThrAspMetSerGlyHisPhe305310315320GlnGlnIleLysAsnIleArgAsnSerLeuGlnGlnProGluGlyLeu325330335AspLysAlaLysThrMetSerLeuIleLeuHisAlaAlaAspIleSer340345350HisProAlaLysSerTrpLysLeuHisHisArgTrpThrMetAlaLeu355360365MetGluGluPhePheLeuGlnGlyAspLysGluAlaGluLeuGlyLeu370375380ProPheSerProLeuCysAspArgLysSerThrMetValAlaGlnSer385390395400GlnIleGlyPheIleAspPheIleValGluProThrPheSerLeuLeu405410415ThrAspSerThrGluLysIleIleIleProLeuIleGluGluAspSer420425430LysThrLysThrProSerTyrGlyAlaSerArgArgSerAsnMetLys435440445GlyThrThrAsnAspGlyThrTyrSerProAspTyrSerLeuAlaSer450455460ValAspLeuLysSerPheLysAsnSerLeuValAspIleIleGlnGln465470475480AsnLysGluArgTrpLysGluLeuAlaAlaGlnGlyGluProAspPro485490495HisLysAsnSerAspLeuValAsnAlaGluGluLysHisAlaGluThr500505510HisSer(2) INFORMATION FOR SEQ ID NO:18:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 23 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:18:ATHCAYGAYTAYGARCAYACNGG23(2) INFORMATION FOR SEQ ID NO:19:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 8 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:19:IleHisAspTyrGluHisThrGly15(2) INFORMATION FOR SEQ ID NO:20:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 32 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:20:TCYTTRTCNCCYTGNCGRAARAAYTCYTCCAT32(2) INFORMATION FOR SEQ ID NO:21:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 11 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:21:MetGluGluPhePheArgGlnGlyAspLysGlu1510(2) INFORMATION FOR SEQ ID NO:22:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 412 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 1..412(xi) SEQUENCE DESCRIPTION: SEQ ID NO:22:ATTCATGATTATAACACACGGGGCACTACCAACAGCTTCCACATCCAG48IleHisAspTyrAsnThrArgGlyThrThrAsnSerPheHisIleGln151015ACCAAATCGGAATGCGCCATCCTGTACAACGACCGCTCAGTGCTGGAG96ThrLysSerGluCysAlaIleLeuTyrAsnAspArgSerValLeuGlu202530AATCACCACATCAGCTCGGTTTTCCGAATGATGCAGGACGACGACATG144AsnHisHisIleSerSerValPheArgMetMetGlnAspAspAspMet354045AACATCTTCATCAACCTCACCAAGGATGAGTTTGTAGAGCTGCGGGCT192AsnIlePheIleAsnLeuThrLysAspGluPheValGluLeuArgAla505560CTGGTCATTGAGATGGTGTTGGCCACAGACATGTCCTGCCATTTCCAG240LeuValIleGluMetValLeuAlaThrAspMetSerCysHisPheGln65707580CAAGTGAAGTCCATGAAGACAGCCTTGCAGCAGCTGGAGAGGATTGAC288GlnValLysSerMetLysThrAlaLeuGlnGlnLeuGluArgIleAsp859095AAGTCCAAGGCCCTCTCTCTGCTGCTTCATGCTGCTGACATCAGCCAC336LysSerLysAlaLeuSerLeuLeuLeuHisAlaAlaAspIleSerHis100105110CCCACCAAGCAGTGGTCGGTTCACAGCCGCTGGACCAAGGCCCTCATG384ProThrLysGlnTrpSerValHisSerArgTrpThrLysAlaLeuMet115120125GAGGAGTTCTTCCGACAAGGGGACAAAG412GluGluPhePheArgGlnGlyAspLys130135(2) INFORMATION FOR SEQ ID NO:23:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 137 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:23:IleHisAspTyrAsnThrArgGlyThrThrAsnSerPheHisIleGln151015ThrLysSerGluCysAlaIleLeuTyrAsnAspArgSerValLeuGlu202530AsnHisHisIleSerSerValPheArgMetMetGlnAspAspAspMet354045AsnIlePheIleAsnLeuThrLysAspGluPheValGluLeuArgAla505560LeuValIleGluMetValLeuAlaThrAspMetSerCysHisPheGln65707580GlnValLysSerMetLysThrAlaLeuGlnGlnLeuGluArgIleAsp859095LysSerLysAlaLeuSerLeuLeuLeuHisAlaAlaAspIleSerHis100105110ProThrLysGlnTrpSerValHisSerArgTrpThrLysAlaLeuMet115120125GluGluPhePheArgGlnGlyAspLys130135(2) INFORMATION FOR SEQ ID NO:24:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 23 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:24:AARAARAAYYTNGARTAYACNGC23(2) INFORMATION FOR SEQ ID NO:25:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 8 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:25:LysLysAsnLeuGluTyrThrAla15(2) INFORMATION FOR SEQ ID NO:26:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 1844 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 114..1715(xi) SEQUENCE DESCRIPTION: SEQ ID NO:26:GGCTGGGCAGCGGGAAAGGAGGAGCCGCAGGAACTGCAGCTCTGCCAGCTTGGGCCGAGC60TTTAGAGACCCCCGGCCTGGCTGGTCCCTGCCAGCCGCAGACGGAGGCTGAGCATG116MetGAGCTGTCCCCCCGCAGCCCTCCCGAGATGCTAGAGTCGGACTGCCCT164GluLeuSerProArgSerProProGluMetLeuGluSerAspCysPro51015TCACCCCTGGAGCTGAAGTCAGCCCCCAGCAAGAAGATGTGGATTAAG212SerProLeuGluLeuLysSerAlaProSerLysLysMetTrpIleLys202530CTCCGGTCTCTGCTGCGCTACATGGTGAAGCAGTTGGAGAACGGGGAG260LeuArgSerLeuLeuArgTyrMetValLysGlnLeuGluAsnGlyGlu354045GTAAACATTGAGGAGCTGAAGAAAAACCTGGAGTACACAGCTTCTCTG308ValAsnIleGluGluLeuLysLysAsnLeuGluTyrThrAlaSerLeu50556065CTGGAGGCCGTCTATATAGATGAGACTCGGCAAATCCTGGACACGGAG356LeuGluAlaValTyrIleAspGluThrArgGlnIleLeuAspThrGlu707580GATGAGCTGCAGGAGCTGCGGTCTGATGCGGTGCCTTCAGAGGTGCGG404AspGluLeuGlnGluLeuArgSerAspAlaValProSerGluValArg859095GACTGGCTGGCCTCCACCTTCACCCAGCAGACCCGGGCCAAAGGCCCG452AspTrpLeuAlaSerThrPheThrGlnGlnThrArgAlaLysGlyPro100105110AGCGAAGAGAAGCCCAAGTTCCGGAGCATCGTGCACGCGGTGCAGGCT500SerGluGluLysProLysPheArgSerIleValHisAlaValGlnAla115120125GGCATCTTTGTGGAGCGGATGTTCCGGAGAACGTACACCTCTGTGGGC548GlyIlePheValGluArgMetPheArgArgThrTyrThrSerValGly130135140145CCCACCTACTCCACTGCCGTCCTCAACTGTCTCAAGAACGTGGACCTT596ProThrTyrSerThrAlaValLeuAsnCysLeuLysAsnValAspLeu150155160TGGTGCTTTGATGTCTTTTCCTTGAACCGGGCAGCAGATGACCACGCC644TrpCysPheAspValPheSerLeuAsnArgAlaAlaAspAspHisAla165170175CTGAGGACCATCGTTTTTGAGCTGCTGACTCGGCACAACCTCATCAGC692LeuArgThrIleValPheGluLeuLeuThrArgHisAsnLeuIleSer180185190CGCTTTAAGATTCCCACTGTGTTTTTGATGACTTTCCTGGATGCCTTG740ArgPheLysIleProThrValPheLeuMetThrPheLeuAspAlaLeu195200205GAGACAGGCTACGGAAAGTACAAGAACCCTTACCACAACCAGATCCAC788GluThrGlyTyrGlyLysTyrLysAsnProTyrHisAsnGlnIleHis210215220225GCAGCTGACGTCACCCAGACGGTCCACTGCTTCTTGCTCCGCACAGGG836AlaAlaAspValThrGlnThrValHisCysPheLeuLeuArgThrGly230235240ATGGTGCACTGCCTGTCGGAGATTGAGGTCCTGGCCATCATCTTTGCT884MetValHisCysLeuSerGluIleGluValLeuAlaIleIlePheAla245250255GCAGCGATCCACGACTATGAGCACACTGGCACTACCAACAGCTTCCAC932AlaAlaIleHisAspTyrGluHisThrGlyThrThrAsnSerPheHis260265270ATCCAGACCAAATCGGAATGCGCCATCCTGTACAACGACCGCTCAGTG980IleGlnThrLysSerGluCysAlaIleLeuTyrAsnAspArgSerVal275280285CTGGAGAATCACCACATCAGCTCGGTTTTCCGAATGATGCAGGACGAC1028LeuGluAsnHisHisIleSerSerValPheArgMetMetGlnAspAsp290295300305GAGATGAACATCTTCATCAACCTCACCAAGGATGAGTTTGTAGAGCTG1076GluMetAsnIlePheIleAsnLeuThrLysAspGluPheValGluLeu310315320CGGGCTCTGGTCATTGAGATGGTGTTGGCCACAGACATGTCCTGCCAT1124ArgAlaLeuValIleGluMetValLeuAlaThrAspMetSerCysHis325330335TTCCAGCAAGTGAAGTCCATGAAGACAGCCTTGCAGCAGCTGGAGAGG1172PheGlnGlnValLysSerMetLysThrAlaLeuGlnGlnLeuGluArg340345350ATTGACAAGTCCAAGGCCCTCTCTCTGCTGCTTCATGCTGCTGACATC1220IleAspLysSerLysAlaLeuSerLeuLeuLeuHisAlaAlaAspIle355360365AGCCACCCCACCAAGCAGTGGTCGGTTCACAGCCGCTGGACCAAGGCC1268SerHisProThrLysGlnTrpSerValHisSerArgTrpThrLysAla370375380385CTCATGGAGGAATTCTTCCGCCAGGGTGACAAGGAGGCTGAGCTGGGC1316LeuMetGluGluPhePheArgGlnGlyAspLysGluAlaGluLeuGly390395400CTGCCCTTTTCTCCGCTCTGTGACCGCACTTCCACCCTCGTGGCGCAG1364LeuProPheSerProLeuCysAspArgThrSerThrLeuValAlaGln405410415TCCCAGATTGGTTTCATCGACTTCATTGTGGAGCCCACGTTCTCTGTG1412SerGlnIleGlyPheIleAspPheIleValGluProThrPheSerVal420425430CTCACCGATGTGGCTGAGAAGAGTGTCCAGCCCACCGGGGACGACGAC1460LeuThrAspValAlaGluLysSerValGlnProThrGlyAspAspAsp435440445TCGAAGTCTAAAAACCAGCCCAGCTTCCAGTGGCGCCAGCCTTCTCTG1508SerLysSerLysAsnGlnProSerPheGlnTrpArgGlnProSerLeu450455460465GATGTAGAAGTGGGAGACCCCAACCCTGACGTGGTCAGCTTCCGCTCC1556AspValGluValGlyAspProAsnProAspValValSerPheArgSer470475480ACCTGGACCAAATACATTCAGGAGAACAAGCAGAAATGGAAGGAACGG1604ThrTrpThrLysTyrIleGlnGluAsnLysGlnLysTrpLysGluArg485490495GCGGCGAGCGGCATCACCAACCAGATGTCCATTGACGAACTGTCCCCT1652AlaAlaSerGlyIleThrAsnGlnMetSerIleAspGluLeuSerPro500505510TGTGAGGAAGAGGCCCCAGCCTCCCCTGCCGAAGACGAGCACAACCAG1700CysGluGluGluAlaProAlaSerProAlaGluAspGluHisAsnGln515520525AACGGGAATCTGGACTAGCGGGGCCTGGCCAGGTCCTCACTGAGTCCTGAGTGTT1755AsnGlyAsnLeuAsp530CGATGTCATCAGCACCATCCATCGGGACTGGCTCCCCCATCTGCTCCGAGGGCGAATGGA1815TGTCAAGGAACAGAAAACCCACCCGAAGA1844(2) INFORMATION FOR SEQ ID NO:27:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 534 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:27:MetGluLeuSerProArgSerProProGluMetLeuGluSerAspCys151015ProSerProLeuGluLeuLysSerAlaProSerLysLysMetTrpIle202530LysLeuArgSerLeuLeuArgTyrMetValLysGlnLeuGluAsnGly354045GluValAsnIleGluGluLeuLysLysAsnLeuGluTyrThrAlaSer505560LeuLeuGluAlaValTyrIleAspGluThrArgGlnIleLeuAspThr65707580GluAspGluLeuGlnGluLeuArgSerAspAlaValProSerGluVal859095ArgAspTrpLeuAlaSerThrPheThrGlnGlnThrArgAlaLysGly100105110ProSerGluGluLysProLysPheArgSerIleValHisAlaValGln115120125AlaGlyIlePheValGluArgMetPheArgArgThrTyrThrSerVal130135140GlyProThrTyrSerThrAlaValLeuAsnCysLeuLysAsnValAsp145150155160LeuTrpCysPheAspValPheSerLeuAsnArgAlaAlaAspAspHis165170175AlaLeuArgThrIleValPheGluLeuLeuThrArgHisAsnLeuIle180185190SerArgPheLysIleProThrValPheLeuMetThrPheLeuAspAla195200205LeuGluThrGlyTyrGlyLysTyrLysAsnProTyrHisAsnGlnIle210215220HisAlaAlaAspValThrGlnThrValHisCysPheLeuLeuArgThr225230235240GlyMetValHisCysLeuSerGluIleGluValLeuAlaIleIlePhe245250255AlaAlaAlaIleHisAspTyrGluHisThrGlyThrThrAsnSerPhe260265270HisIleGlnThrLysSerGluCysAlaIleLeuTyrAsnAspArgSer275280285ValLeuGluAsnHisHisIleSerSerValPheArgMetMetGlnAsp290295300AspGluMetAsnIlePheIleAsnLeuThrLysAspGluPheValGlu305310315320LeuArgAlaLeuValIleGluMetValLeuAlaThrAspMetSerCys325330335HisPheGlnGlnValLysSerMetLysThrAlaLeuGlnGlnLeuGlu340345350ArgIleAspLysSerLysAlaLeuSerLeuLeuLeuHisAlaAlaAsp355360365IleSerHisProThrLysGlnTrpSerValHisSerArgTrpThrLys370375380AlaLeuMetGluGluPhePheArgGlnGlyAspLysGluAlaGluLeu385390395400GlyLeuProPheSerProLeuCysAspArgThrSerThrLeuValAla405410415GlnSerGlnIleGlyPheIleAspPheIleValGluProThrPheSer420425430ValLeuThrAspValAlaGluLysSerValGlnProThrGlyAspAsp435440445AspSerLysSerLysAsnGlnProSerPheGlnTrpArgGlnProSer450455460LeuAspValGluValGlyAspProAsnProAspValValSerPheArg465470475480SerThrTrpThrLysTyrIleGlnGluAsnLysGlnLysTrpLysGlu485490495ArgAlaAlaSerGlyIleThrAsnGlnMetSerIleAspGluLeuSer500505510ProCysGluGluGluAlaProAlaSerProAlaGluAspGluHisAsn515520525GlnAsnGlyAsnLeuAsp530(2) INFORMATION FOR SEQ ID NO:28:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 14 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:28:GlnLeuGluAsnGlyGluValAsnIleGluGluLeuLysLys1510(2) INFORMATION FOR SEQ ID NO:29:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 14 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:29:GlnLeuIleProGlyArgValAsnIleIleSerLeuLysLys1510(2) INFORMATION FOR SEQ ID NO:30:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 16 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:30:LysSerGluCysAlaIleLeuTyrAsnAspArgSerValLeuGluAsn151015(2) INFORMATION FOR SEQ ID NO:31:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 16 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:31:LysAspGluThrAlaIleLeuTyrAsnAspArgThrValLeuGluAsn151015(2) INFORMATION FOR SEQ ID NO:32:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 34 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:32:GGATCCGGATCCCGCAGACGGAGGCTGAGCATGG34(2) INFORMATION FOR SEQ ID NO:33:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 32 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:33:GGATCCGGATCCAGGACCTGGCCAGGCCCGGC32(2) INFORMATION FOR SEQ ID NO:34:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 8 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:34:GluMetMetMetTyrHisMetLys15(2) INFORMATION FOR SEQ ID NO:35:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 8 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:35:TyrHisAsnTrpMetHisAlaPhe15(2) INFORMATION FOR SEQ ID NO:36:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 23 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:36:TTCATRTGRTACATCATCATYTC23(2) INFORMATION FOR SEQ ID NO:37:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 23 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:37:AANGCRTGCATCCARTTRTGRTA23(2) INFORMATION FOR SEQ ID NO:38:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 4131 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 148..2910(xi) SEQUENCE DESCRIPTION: SEQ ID NO:38:AGGCGCAGCGGCCGGGCCGGCGGGCGGGCGGGCGGCTGCGAGCATGGTCCTGGTGCTGCA60CCACATCCTCATCGCTGTTGTCCAATTCTTCAGGCGGGGCCAGCAGGTCTTCCTCAAGCC120GGACGAGCCGCCGCCGCCGCCGCAGCCATGCGCCGACAGCCTGCAGCCAGC171MetArgArgGlnProAlaAlaSer15CGGGACCTCTTTGCACAGGAGCCAGTGCCCCCAGGGAGTGGAGACGGC219ArgAspLeuPheAlaGlnGluProValProProGlySerGlyAspGly101520GCATTGCAGGATGCTTTGCTGAGCCTGGGCTCCGTCATCGACGTTGCA267AlaLeuGlnAspAlaLeuLeuSerLeuGlySerValIleAspValAla25303540GGCTTGCAACAGGCTGTCAAGGAGGCCCTGTCGGCTGTGCTTCCCAAA315GlyLeuGlnGlnAlaValLysGluAlaLeuSerAlaValLeuProLys455055GTGGAGACGGTCTACACCTACCTGCTGGATGGGGAATCCCGGCTGGTG363ValGluThrValTyrThrTyrLeuLeuAspGlyGluSerArgLeuVal606570TGTGAGGAGCCCCCCCACGAGCTGCCCCAGGAGGGGAAAGTGCGAGAG411CysGluGluProProHisGluLeuProGlnGluGlyLysValArgGlu758085GCTGTGATCTCCCGGAAGCGGCTGGGCTGCAATGGACTGGGCCCCTCA459AlaValIleSerArgLysArgLeuGlyCysAsnGlyLeuGlyProSer9095100GACCTGCCTGGGAAGCCCTTGGCAAGGCTGGTGGCTCCACTGGCTCCT507AspLeuProGlyLysProLeuAlaArgLeuValAlaProLeuAlaPro105110115120GACACCCAAGTGCTGGTCATACCGCTGGTGGACAAGGAGGCCGGGGCT555AspThrGlnValLeuValIleProLeuValAspLysGluAlaGlyAla125130135GTGGCAGCTGTCATCTTGGTGCACTGTGGTCAGCTGAGTGACAATGAG603ValAlaAlaValIleLeuValHisCysGlyGlnLeuSerAspAsnGlu140145150GAGTGGAGCCTGCAAGCTGTGGAGAAGCATACCCTGGTGGCCCTGAAA651GluTrpSerLeuGlnAlaValGluLysHisThrLeuValAlaLeuLys155160165AGGGTGCAGGCCTTGCAGCAGCGCGAGTCCAGCGTGGCCCCGGAAGCG699ArgValGlnAlaLeuGlnGlnArgGluSerSerValAlaProGluAla170175180ACCCAGAATCCTCCGGAGGAGGCAGCGGGAGACCAGAAGGGTGGGGTC747ThrGlnAsnProProGluGluAlaAlaGlyAspGlnLysGlyGlyVal185190195200GCATACACAAACCAAGACCGAAAGATCCTGCAGCTTTGCGGGGAGCTC795AlaTyrThrAsnGlnAspArgLysIleLeuGlnLeuCysGlyGluLeu205210215TACGACCTGGATGCATCTTCCCTGCAGCTCAAAGTCCTCCAATATCTG843TyrAspLeuAspAlaSerSerLeuGlnLeuLysValLeuGlnTyrLeu220225230CAACAGGAGACCCAGGCATCCCGCTGCTGCCTGCTGCTGGTATCCGAG891GlnGlnGluThrGlnAlaSerArgCysCysLeuLeuLeuValSerGlu235240245GACAATCTTCAGCTCTCCTGCAAGGTCATTGGAGATAAAGTACTGGAG939AspAsnLeuGlnLeuSerCysLysValIleGlyAspLysValLeuGlu250255260GAAGAGATCAGCTTTCCGTTGACCACAGGACGCCTGGGCCAAGTGGTG987GluGluIleSerPheProLeuThrThrGlyArgLeuGlyGlnValVal265270275280GAAGACAAGAAGTCTATCCAGCTGAAAGATCTCACCTCCGAGGATATG1035GluAspLysLysSerIleGlnLeuLysAspLeuThrSerGluAspMet285290295CAACAGCTGCAAAGCATGTTGGGCTGTGAGGTGCAGGCCATGCTCTGT1083GlnGlnLeuGlnSerMetLeuGlyCysGluValGlnAlaMetLeuCys300305310GTCCCTGTCATCAGCCGGGCCACTGACCAGGTCGTGGCCCTGGCCTGT1131ValProValIleSerArgAlaThrAspGlnValValAlaLeuAlaCys315320325GCCTTCAACAAGCTCGGAGGAGACTTGTTCACAGACCAGGACGAGCAC1179AlaPheAsnLysLeuGlyGlyAspLeuPheThrAspGlnAspGluHis330335340GTGATCCAGCACTGCTTCCACTACACCAGCACAGTGCTCACCAGCACC1227ValIleGlnHisCysPheHisTyrThrSerThrValLeuThrSerThr345350355360CTGGCCTTCCAGAAGGAGCAGAAGCTCAAGTGTGAGTGCCAGGCTCTT1275LeuAlaPheGlnLysGluGlnLysLeuLysCysGluCysGlnAlaLeu365370375CTCCAAGTGGCGAAGAACCTCTTCACTCATCTGGATGACGTCTCCGTG1323LeuGlnValAlaLysAsnLeuPheThrHisLeuAspAspValSerVal380385390CTGCTCCAGGAGATCATCACAGAGGCCAGGAACCTCAGCAATGCTGAG1371LeuLeuGlnGluIleIleThrGluAlaArgAsnLeuSerAsnAlaGlu395400405ATCTGCTCTGTGTTCCTGCTGGATCAGAACGAGCTGGTGGCCAAGGTG1419IleCysSerValPheLeuLeuAspGlnAsnGluLeuValAlaLysVal410415420TTCGATGGGGGTGTGGTGGAAGATGAGAGCTATGAGATCCGCATTCCC1467PheAspGlyGlyValValGluAspGluSerTyrGluIleArgIlePro425430435440GCTGACCAGGGCATCGCGGGTCATGTGGCGACCACCGGCCAGATCCTA1515AlaAspGlnGlyIleAlaGlyHisValAlaThrThrGlyGlnIleLeu445450455AACATCCCAGATGCTTACGCACATCCGCTTTTCTACCGAGGCGTGGAC1563AsnIleProAspAlaTyrAlaHisProLeuPheTyrArgGlyValAsp460465470GACAGCACCGGCTTCCGGACGCGCAACATCCTCTGCTTCCCCATCAAG1611AspSerThrGlyPheArgThrArgAsnIleLeuCysPheProIleLys475480485AACGAGAACCAGGAGGTCATCGGTGTGGCCGAGCTGGTGAACAAGATC1659AsnGluAsnGlnGluValIleGlyValAlaGluLeuValAsnLysIle490495500AATGGACCATGGTTCAGCAAGTTTGATGAAGACCTGGCTACAGCCTTC1707AsnGlyProTrpPheSerLysPheAspGluAspLeuAlaThrAlaPhe505510515520TCCATCTACTGTGGCATCAGCATTGCCCATTCCCTCCTATACAAGAAA1755SerIleTyrCysGlyIleSerIleAlaHisSerLeuLeuTyrLysLys525530535GTGAATGAGGCGCAGTATCGCAGCCACCTTGCCAATGAGATGATGATG1803ValAsnGluAlaGlnTyrArgSerHisLeuAlaAsnGluMetMetMet540545550TACCACATGAAGGTCTCTGATGACGAGTACACCAAACTTCTCCATGAC1851TyrHisMetLysValSerAspAspGluTyrThrLysLeuLeuHisAsp555560565GGGATCCAGCCTGTGGCTGCCATCGACTCCAACTTTGCCAGTTTCACA1899GlyIleGlnProValAlaAlaIleAspSerAsnPheAlaSerPheThr570575580TACACTCCTCGCTCTCTGCCCGAGGATGACACTTCCATGGCCATCCTG1947TyrThrProArgSerLeuProGluAspAspThrSerMetAlaIleLeu585590595600AGCATGCTGCAGGACATGAATTTCATCAATAACTACAAAATTGACTGC1995SerMetLeuGlnAspMetAsnPheIleAsnAsnTyrLysIleAspCys605610615CCGACACTGGCCCGGTTCTGTTTGATGGTGAAGAAGGGCTACCGGGAT2043ProThrLeuAlaArgPheCysLeuMetValLysLysGlyTyrArgAsp620625630CCCCCCTACCACAACTGGATGCACGCCTTTTCTGTCTCCCACTTCTGC2091ProProTyrHisAsnTrpMetHisAlaPheSerValSerHisPheCys635640645TACCTGCTCTACAAGAACCTGGAGCTCACCAACTACCTCGAGGACATG2139TyrLeuLeuTyrLysAsnLeuGluLeuThrAsnTyrLeuGluAspMet650655660GAGATCTTTGCCTTGTTTATTTCCTGCATGTGTCACGACCTGGACCAC2187GluIlePheAlaLeuPheIleSerCysMetCysHisAspLeuAspHis665670675680AGAGGCACAAACAACTCCTTCCAGGTGGCCTCGAAATCTGTGCTGGCC2235ArgGlyThrAsnAsnSerPheGlnValAlaSerLysSerValLeuAla685690695GCGCTCTACAGCTCGGAAGGCTCTGTCATGGAGAGGCACCACTTCGCT2283AlaLeuTyrSerSerGluGlySerValMetGluArgHisHisPheAla700705710CAGGCCATTGCCATCCTCAACACCCACGGCTGCAACATCTTTGACCAC2331GlnAlaIleAlaIleLeuAsnThrHisGlyCysAsnIlePheAspHis715720725TTCTCCCGGAAGGATTATCAGCGCATGTTGGACCTGATGCGGGACATC2379PheSerArgLysAspTyrGlnArgMetLeuAspLeuMetArgAspIle730735740ATCTTGGCCACAGATCTGGCCCACCACCTCCGCATCTTCAAGGACCTC2427IleLeuAlaThrAspLeuAlaHisHisLeuArgIlePheLysAspLeu745750755760CAAAAGATGGCCGAAGTGGGCTATGATCGAACCAACAAGCAGCACCAC2475GlnLysMetAlaGluValGlyTyrAspArgThrAsnLysGlnHisHis765770775AGCCTCCTTCTCTGCCTCCTTATGACCTCCTGTGACCTCTCTGACCAG2523SerLeuLeuLeuCysLeuLeuMetThrSerCysAspLeuSerAspGln780785790ACCAAGGGCTGGAAGACCACGAGGAAGATCGCGGAGCTGATCTACAAA2571ThrLysGlyTrpLysThrThrArgLysIleAlaGluLeuIleTyrLys795800805GAGTTCTTCTCCCAGGGAGACTTGGAGAAGGCCATGGGCAACAGGCCG2619GluPhePheSerGlnGlyAspLeuGluLysAlaMetGlyAsnArgPro810815820ATGGAGATGATGGACCGTGAGAAGGCCTACATCCCCGAGCTGCAGATC2667MetGluMetMetAspArgGluLysAlaTyrIleProGluLeuGlnIle825830835840AGCTTCATGGAGCACATCGCAATGCCCATCTACAAGCTGCTGCAAGAC2715SerPheMetGluHisIleAlaMetProIleTyrLysLeuLeuGlnAsp845850855CTGTTCCCCAAGGCGGCCGAGTTGTACGAACGCGTGGCCTCTAATCGT2763LeuPheProLysAlaAlaGluLeuTyrGluArgValAlaSerAsnArg860865870GAGCACTGGACCAAGGTGTCACACAAGTTCACCATCCGAGGCCTCCCG2811GluHisTrpThrLysValSerHisLysPheThrIleArgGlyLeuPro875880885AGCAACAACTCGTTGGACTTCCTGGACGAGGAGTATGAGGTGCCTGAC2859SerAsnAsnSerLeuAspPheLeuAspGluGluTyrGluValProAsp890895900CTGGATGGCGCTAGGGCTCCCATCAATGGCTGTTGCAGCCTTGATGCT2907LeuAspGlyAlaArgAlaProIleAsnGlyCysCysSerLeuAspAla905910915920GAGTGAGTCCCTCCTGGGACCCCTCCCTGTCCAGGCCTCCTCCCACAAGCCTC2960GluCACGGGCCTGGCCGCACGCCCTGGGACCAGAGCCAAGGGTCCTGGATTCTAGGCCAGGAC3020TTCCCATGTGACCCGGGCGAGGTCTGACCTTCCCGGGCCTCAGCTTTCTTGTCTGTATAA3080TGGAAGACTTCAGCCTCACTGAGACTTTGTCACTTGTCCTCTGAGAGCACAGGGGTAACC3140AATGAGCAGTGGACCCTGCTCTGCACCTCTGACCGCATCTTGGCAAGTCCCCACCCTCCA3200GGCCACTCCTTCTCTGAGGCAGCCGGATGGTTTCTTCTGGGCCCCATTCCTGCCCTACCA3260GACCTGTGCCCTTTCCTGTGGGGGCACCCTCACTGGCTCCCAGGATCCTCAGGCAAGAAC3320ATGAGACATCTGAGTGGGCAAAGGGTGGGTCTTAGAGACAGTTATCAGCCTGGCTGGAGG3380ACTAGAAGTAGCCATGGGACCACCTGTGGCCCAGAGGACTGCCTTTGTACTTATGGTGGG3440GACTGGGACCTGGGGATATAAGGGTCCCAGGAGGACACTGCCAGGGGGCCAGTGCAGTGC3500TCTGGGGAGAGGGGGCTCAGGAAGAGAGGAGGATAAGAACAGTGAGAAGGAAGGATCCCT3560GGGTTGGGAGGCAGGCCCAGCATGGGTCAGCCATGCTTCCTCCTGGCTGTGTGACCCTGG3620GCAAGTCCCTTCCCCTCTCTGCGAAACAGTAGGGTGAGACAATCCATTCTCTAAGACCCC3680TTTTAGATCCAAGTCCCCATAGTTCTGTGGAGTCCCAGTAGAGGCCACCGAGGGTCCCTG3740GCCCCCTTGGGCACAGAGCTGACACTGAGTCCCTCAGTGGCCCCCTGAGTATACCCCCTT3800AGCCGGAGCCCCTTCCCCATTCCTACAGCCAGAGGGGGACCTGGCCTCAGCCTGGCAGGG3860CCTCTCTCCTCTTCAAGGCCATATCCACCTGTGCCCCGGGGCTTGGGAGACCCCCTAGGG3920CCGGAGCTCTGGGGTCATCCTGGCCACTGGCTTCTCCTTTCTCTGTTTTGTTCTGTATGT3980GTTGTGGGGTGGGGGGAGGGGGGCCACCTGCCTTACCTATTCTGAGTTGCCTTTAGAGAG4040ATGCGTTTTTTCTAGGACTCTGTGCAACTGTTGTATATGGTTCCGTGGGCTGACCGCTTT4100GTACATGAGAATAAATCTATTTCTTTCTACC4131(2) INFORMATION FOR SEQ ID NO:39:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 921 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:39:MetArgArgGlnProAlaAlaSerArgAspLeuPheAlaGlnGluPro151015ValProProGlySerGlyAspGlyAlaLeuGlnAspAlaLeuLeuSer202530LeuGlySerValIleAspValAlaGlyLeuGlnGlnAlaValLysGlu354045AlaLeuSerAlaValLeuProLysValGluThrValTyrThrTyrLeu505560LeuAspGlyGluSerArgLeuValCysGluGluProProHisGluLeu65707580ProGlnGluGlyLysValArgGluAlaValIleSerArgLysArgLeu859095GlyCysAsnGlyLeuGlyProSerAspLeuProGlyLysProLeuAla100105110ArgLeuValAlaProLeuAlaProAspThrGlnValLeuValIlePro115120125LeuValAspLysGluAlaGlyAlaValAlaAlaValIleLeuValHis130135140CysGlyGlnLeuSerAspAsnGluGluTrpSerLeuGlnAlaValGlu145150155160LysHisThrLeuValAlaLeuLysArgValGlnAlaLeuGlnGlnArg165170175GluSerSerValAlaProGluAlaThrGlnAsnProProGluGluAla180185190AlaGlyAspGlnLysGlyGlyValAlaTyrThrAsnGlnAspArgLys195200205IleLeuGlnLeuCysGlyGluLeuTyrAspLeuAspAlaSerSerLeu210215220GlnLeuLysValLeuGlnTyrLeuGlnGlnGluThrGlnAlaSerArg225230235240CysCysLeuLeuLeuValSerGluAspAsnLeuGlnLeuSerCysLys245250255ValIleGlyAspLysValLeuGluGluGluIleSerPheProLeuThr260265270ThrGlyArgLeuGlyGlnValValGluAspLysLysSerIleGlnLeu275280285LysAspLeuThrSerGluAspMetGlnGlnLeuGlnSerMetLeuGly290295300CysGluValGlnAlaMetLeuCysValProValIleSerArgAlaThr305310315320AspGlnValValAlaLeuAlaCysAlaPheAsnLysLeuGlyGlyAsp325330335LeuPheThrAspGlnAspGluHisValIleGlnHisCysPheHisTyr340345350ThrSerThrValLeuThrSerThrLeuAlaPheGlnLysGluGlnLys355360365LeuLysCysGluCysGlnAlaLeuLeuGlnValAlaLysAsnLeuPhe370375380ThrHisLeuAspAspValSerValLeuLeuGlnGluIleIleThrGlu385390395400AlaArgAsnLeuSerAsnAlaGluIleCysSerValPheLeuLeuAsp405410415GlnAsnGluLeuValAlaLysValPheAspGlyGlyValValGluAsp420425430GluSerTyrGluIleArgIleProAlaAspGlnGlyIleAlaGlyHis435440445ValAlaThrThrGlyGlnIleLeuAsnIleProAspAlaTyrAlaHis450455460ProLeuPheTyrArgGlyValAspAspSerThrGlyPheArgThrArg465470475480AsnIleLeuCysPheProIleLysAsnGluAsnGlnGluValIleGly485490495ValAlaGluLeuValAsnLysIleAsnGlyProTrpPheSerLysPhe500505510AspGluAspLeuAlaThrAlaPheSerIleTyrCysGlyIleSerIle515520525AlaHisSerLeuLeuTyrLysLysValAsnGluAlaGlnTyrArgSer530535540HisLeuAlaAsnGluMetMetMetTyrHisMetLysValSerAspAsp545550555560GluTyrThrLysLeuLeuHisAspGlyIleGlnProValAlaAlaIle565570575AspSerAsnPheAlaSerPheThrTyrThrProArgSerLeuProGlu580585590AspAspThrSerMetAlaIleLeuSerMetLeuGlnAspMetAsnPhe595600605IleAsnAsnTyrLysIleAspCysProThrLeuAlaArgPheCysLeu610615620MetValLysLysGlyTyrArgAspProProTyrHisAsnTrpMetHis625630635640AlaPheSerValSerHisPheCysTyrLeuLeuTyrLysAsnLeuGlu645650655LeuThrAsnTyrLeuGluAspMetGluIlePheAlaLeuPheIleSer660665670CysMetCysHisAspLeuAspHisArgGlyThrAsnAsnSerPheGln675680685ValAlaSerLysSerValLeuAlaAlaLeuTyrSerSerGluGlySer690695700ValMetGluArgHisHisPheAlaGlnAlaIleAlaIleLeuAsnThr705710715720HisGlyCysAsnIlePheAspHisPheSerArgLysAspTyrGlnArg725730735MetLeuAspLeuMetArgAspIleIleLeuAlaThrAspLeuAlaHis740745750HisLeuArgIlePheLysAspLeuGlnLysMetAlaGluValGlyTyr755760765AspArgThrAsnLysGlnHisHisSerLeuLeuLeuCysLeuLeuMet770775780ThrSerCysAspLeuSerAspGlnThrLysGlyTrpLysThrThrArg785790795800LysIleAlaGluLeuIleTyrLysGluPhePheSerGlnGlyAspLeu805810815GluLysAlaMetGlyAsnArgProMetGluMetMetAspArgGluLys820825830AlaTyrIleProGluLeuGlnIleSerPheMetGluHisIleAlaMet835840845ProIleTyrLysLeuLeuGlnAspLeuPheProLysAlaAlaGluLeu850855860TyrGluArgValAlaSerAsnArgGluHisTrpThrLysValSerHis865870875880LysPheThrIleArgGlyLeuProSerAsnAsnSerLeuAspPheLeu885890895AspGluGluTyrGluValProAspLeuAspGlyAlaArgAlaProIle900905910AsnGlyCysCysSerLeuAspAlaGlu915920(2) INFORMATION FOR SEQ ID NO:40:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 249 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:40:ATATCGAATTCGGTTTAGTCTGGTTGGGGAGGCAGACGATGAGGAGCGATGGGGCAGGCA60TGCGGCCACTCCATCCTCTGCAGGAGCCAGCAGTACCCGGCTGCGCGACCGGCTGAGCCG120CGGGGCCAGCAGGTCTTCCTCAAGCCGGACGAGCCGCCGCCGCCGCCGCAGCCATGCGCC180GACAGCCTGCAGGATGCTTTGCTGAGCCTGGGCTCCGTCATTGAGCTTGCAGGCTTGCGA240CAGGCTGTC249(2) INFORMATION FOR SEQ ID NO:41:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 250 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(iv) ANTI-SENSE: YES(xi) SEQUENCE DESCRIPTION: SEQ ID NO:41:GAATTCGGGTAGAGCAGGTAGCAGAAGTGGGAGACAGAAAAGGCGTGCATCCAGTTGTGG60TAGGGGGGATCCCGGTAGCCCTTCTTCACCATCAAACAGAACCGGGCCAGTGTCGGGCAG120TCAATTTTGTAGTTATTGATGAAATTCATGTTCTGCAGCATGCTCAGGATGGCCATGGAG180TGTCATCCTTGGGCAGAGAGCGAGGAGTGTATGTGAACTGGCAAGTTGGAGTCGATGGCA240GCCACAGGCT250(2) INFORMATION FOR SEQ ID NO:42:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 3789 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 181..3006(xi) SEQUENCE DESCRIPTION: SEQ ID NO:42:GCGGGAACTGCCAGGGCAGCAGGGCTGGATTGGGGTGTTGAGTCCAGGCTGAGTCGGGGA60CAGGCCACTGTTCTTGGTCCCCGTGCCTGCTGGGCCAGGCGCCCTGCCTGGAGCCCCGGG120CAGGGTGGACAGGGTGAGGTGCCACTTTAGTCTGGTTGGGGAGGCAGACGATGAGGAGCG180ATGGGGCAGGCATGCGGCCACTCCATCCTCTGCAGGAGCCAGCAGTAC228MetGlyGlnAlaCysGlyHisSerIleLeuCysArgSerGlnGlnTyr151015CCGGCTGCGCGACCGGCTGAGCCGCGGGGCCAGCAGGTCTTCCTCAAG276ProAlaAlaArgProAlaGluProArgGlyGlnGlnValPheLeuLys202530CCGGACGAGCCGCCGCCGCCGCCGCAGCCATGCGCCGACAGCCTGCAG324ProAspGluProProProProProGlnProCysAlaAspSerLeuGln354045GATGCTTTGCTGAGCCTGGGCTCCGTCATTGACGTTGCAGGCTTGCAA372AspAlaLeuLeuSerLeuGlySerValIleAspValAlaGlyLeuGln505560CAGGCTGTCAAGGAGGCCCTGTCGGCTGTGCTTCCCAAAGTGGAGACG420GlnAlaValLysGluAlaLeuSerAlaValLeuProLysValGluThr65707580GTCTACACCTACCTGCTGGATGGGGAATCCCGGCTGGTGTGTGAGGAG468ValTyrThrTyrLeuLeuAspGlyGluSerArgLeuValCysGluGlu859095CCCCCCCACGAGCTGCCCCAGGAGGGGAAAGTGCGAGAGGCTGTGATC516ProProHisGluLeuProGlnGluGlyLysValArgGluAlaValIle100105110TCCCGGAAGCGGCTGGGCTGCAATGGACTGGGCCCCTCAGACCTGCCT564SerArgLysArgLeuGlyCysAsnGlyLeuGlyProSerAspLeuPro115120125GGGAAGCCCTTGGCAAGGCTGGTGGCTCCACTGGCTCCTGACACCCAA612GlyLysProLeuAlaArgLeuValAlaProLeuAlaProAspThrGln130135140GTGCTGGTCATACCGCTGGTGGACAAGGAGGCCGGGGCTGTGGCAGCT660ValLeuValIleProLeuValAspLysGluAlaGlyAlaValAlaAla145150155160GTCATCTTGGTGCACTGTGGTCAGCTGAGTGACAATGAGGAGTGGAGC708ValIleLeuValHisCysGlyGlnLeuSerAspAsnGluGluTrpSer165170175CTGCAAGCTGTGGAGAAGCATACCCTGGTGGCCCTGAAAAGGGTGCAG756LeuGlnAlaValGluLysHisThrLeuValAlaLeuLysArgValGln180185190GCCTTGCAGCAGCGCGAGTCCAGCGTGGCCCCGGAAGCGACCCAGAAT804AlaLeuGlnGlnArgGluSerSerValAlaProGluAlaThrGlnAsn195200205CCTCCGGAGGAGGCAGCGGGAGACCAGAAGGGTGGGGTCGCATACACA852ProProGluGluAlaAlaGlyAspGlnLysGlyGlyValAlaTyrThr210215220GACCAAGACCGAAAGATCCTGCAGCTTTGCGGGGAGCTCTACGACCTG900AspGlnAspArgLysIleLeuGlnLeuCysGlyGluLeuTyrAspLeu225230235240GATGCATCTTCCCTGCAGCTCAAAGTCCTCCAATATCTGCAACAGGAG948AspAlaSerSerLeuGlnLeuLysValLeuGlnTyrLeuGlnGlnGlu245250255ACCCAGGCATCCCGCTGCTGCCTGCTGCTGGTATCCGAGGACAATCTT996ThrGlnAlaSerArgCysCysLeuLeuLeuValSerGluAspAsnLeu260265270CAGCTCTCCTGCAAGGTCATTGGAGATAAAGTACTGGAGGAAGAGATC1044GlnLeuSerCysLysValIleGlyAspLysValLeuGluGluGluIle275280285AGCTTTCCGTTGACCACAGGACGCCTGGGCCAAGTGGTGGAAGACAAG1092SerPheProLeuThrThrGlyArgLeuGlyGlnValValGluAspLys290295300AAGTCTATCCAGCTGAAAGATCTCACCTCCGAGGATATGCAACAGCTG1140LysSerIleGlnLeuLysAspLeuThrSerGluAspMetGlnGlnLeu305310315320CAAAGCATGTTGGGCTGTGAGGTGCAGGCCATGCTCTGTGTCCCTGTC1188GlnSerMetLeuGlyCysGluValGlnAlaMetLeuCysValProVal325330335ATCAGCCGGGCCACTGACCAGGTCGTGGCCCTGGCCTGTGCCTTCAAC1236IleSerArgAlaThrAspGlnValValAlaLeuAlaCysAlaPheAsn340345350AAGCTCGGAGGAGACTTGTTCACAGACCAGGACGAGCACGTGATCCAG1284LysLeuGlyGlyAspLeuPheThrAspGlnAspGluHisValIleGln355360365CACTGCTTCCACTACACCAGCACAGTGCTCACCAGCACCCTGGCCTTC1332HisCysPheHisTyrThrSerThrValLeuThrSerThrLeuAlaPhe370375380CAGAAGGAGCAGAAGCTCAAGTGTGAGTGCCAGGCTCTTCTCCAAGTG1380GlnLysGluGlnLysLeuLysCysGluCysGlnAlaLeuLeuGlnVal385390395400GCGAAGAACCTCTTCACTCATCTGGATGACGTCTCCGTGCTGCTCCAG1428AlaLysAsnLeuPheThrHisLeuAspAspValSerValLeuLeuGln405410415GAGATCATCACAGAGGCCAGGAACCTCAGCAATGCTGAGATCTGCTCT1476GluIleIleThrGluAlaArgAsnLeuSerAsnAlaGluIleCysSer420425430GTGTTCCTGCTGGATCAGAACGAGCTGGTGGCCAAGGTGTTCGATGGG1524ValPheLeuLeuAspGlnAsnGluLeuValAlaLysValPheAspGly435440445GGTGTGGTGGAAGATGAGAGCTATGAGATCCGCATTCCCGCTGACCAG1572GlyValValGluAspGluSerTyrGluIleArgIleProAlaAspGln450455460GGCATCGCGGGTCATGTGGCGACCACCGGCCAGATCCTAAACATCCCA1620GlyIleAlaGlyHisValAlaThrThrGlyGlnIleLeuAsnIlePro465470475480GATGCTTACGCACATCCGCTTTTCTACCGAGGCGTGGACGACAGCACC1668AspAlaTyrAlaHisProLeuPheTyrArgGlyValAspAspSerThr485490495GGCTTCCGGACGCGCAACATCCTCTGCTTCCCCATCAAGAACGAGAAC1716GlyPheArgThrArgAsnIleLeuCysPheProIleLysAsnGluAsn500505510CAGGAGGTCATCGGTGTGGCCGAGCTGGTGAACAAGATCAATGGACCA1764GlnGluValIleGlyValAlaGluLeuValAsnLysIleAsnGlyPro515520525TGGTTCAGCAAGTTTGATGAAGACCTGGCTACAGCCTTCTCCATCTAC1812TrpPheSerLysPheAspGluAspLeuAlaThrAlaPheSerIleTyr530535540TGTGGCATCAGCATTGCCCATTCCCTCCTATACAAGAAAGTGAATGAG1860CysGlyIleSerIleAlaHisSerLeuLeuTyrLysLysValAsnGlu545550555560GCGCAGTATCGCAGCCACCTTGCCAATGAGATGATGATGTACCACATG1908AlaGlnTyrArgSerHisLeuAlaAsnGluMetMetMetTyrHisMet565570575AAGGTCTCTGATGACGAGTACACCAAACTTCTCCATGACGGGATCCAG1956LysValSerAspAspGluTyrThrLysLeuLeuHisAspGlyIleGln580585590CCTGTGGCTGCCATCGACTCCAACTTTGCCAGTTTCACATACACTCCT2004ProValAlaAlaIleAspSerAsnPheAlaSerPheThrTyrThrPro595600605CGCTCTCTGCCCGAGGATGACACTTCCATGGCCATCCTGAGCATGCTG2052ArgSerLeuProGluAspAspThrSerMetAlaIleLeuSerMetLeu610615620CAGGACATGAATTTCATCAATAACTACAAAATTGACTGCCCGACACTG2100GlnAspMetAsnPheIleAsnAsnTyrLysIleAspCysProThrLeu625630635640GCCCGGTTCTGTTTGATGGTGAAGAAGGGCTACCGGGATCCCCCCTAC2148AlaArgPheCysLeuMetValLysLysGlyTyrArgAspProProTyr645650655CACAACTGGATGCACGCCTTTTCTGTCTCCCACTTCTGCTACCTGCTC2196HisAsnTrpMetHisAlaPheSerValSerHisPheCysTyrLeuLeu660665670TACAAGAACCTGGAGCTCACCAACTACCTCGAGGACATGGAGATCTTT2244TyrLysAsnLeuGluLeuThrAsnTyrLeuGluAspMetGluIlePhe675680685GCCTTGTTTATTTCCTGCATGTGTCACGACCTGGACCACAGAGGCACA2292AlaLeuPheIleSerCysMetCysHisAspLeuAspHisArgGlyThr690695700AACAACTCCTTCCAGGTGGCCTCGAAATCTGTGCTGGCCGCGCTCTAC2340AsnAsnSerPheGlnValAlaSerLysSerValLeuAlaAlaLeuTyr705710715720AGCTCGGAAGGCTCTGTCATGGAGAGGCACCACTTCGCTCAGGCCATT2388SerSerGluGlySerValMetGluArgHisHisPheAlaGlnAlaIle725730735GCCATCCTCAACACCCACGGCTGCAACATCTTTGACCACTTCTCCCGG2436AlaIleLeuAsnThrHisGlyCysAsnIlePheAspHisPheSerArg740745750AAGGATTATCAGCGCATGTTGGACCTGATGCGGGACATCATCTTGGCC2484LysAspTyrGlnArgMetLeuAspLeuMetArgAspIleIleLeuAla755760765ACAGATCTGGCCCACCACCTCCGCATCTTCAAGGACCTCCAAAAGATG2532ThrAspLeuAlaHisHisLeuArgIlePheLysAspLeuGlnLysMet770775780GCCGAAGTGGGCTATGATCGAACCAACAAGCAGCACCACAGCCTCCTT2580AlaGluValGlyTyrAspArgThrAsnLysGlnHisHisSerLeuLeu785790795800CTCTGCCTCCTTATGACCTCCTGTGACCTCTCTGACCAGACCAAGGGC2628LeuCysLeuLeuMetThrSerCysAspLeuSerAspGlnThrLysGly805810815TGGAAGACCACGAGGAAGATCGCGGAGCTGATCTACAAAGAGTTCTTC2676TrpLysThrThrArgLysIleAlaGluLeuIleTyrLysGluPhePhe820825830TCCCAGGGAGACTTGGAGAAGGCCATGGGCAACAGGCCGATGGAGATG2724SerGlnGlyAspLeuGluLysAlaMetGlyAsnArgProMetGluMet835840845ATGGACCGTGAGAAGGCCTACATCCCCGAGCTGCAGATCAGCTTCATG2772MetAspArgGluLysAlaTyrIleProGluLeuGlnIleSerPheMet850855860GAGCACATCGCAATGCCCATCTACAAGCTGCTGCAAGACCTGTTCCCC2820GluHisIleAlaMetProIleTyrLysLeuLeuGlnAspLeuPhePro865870875880AAGGCGGCCGAGTTGTACGAACGCGTGGCCTCTAATCGTGAGCACTGG2868LysAlaAlaGluLeuTyrGluArgValAlaSerAsnArgGluHisTrp885890895ACCAAGGTGTCACACAAGTTCACCATCCGAGGCCTCCCGAGCAACAAC2916ThrLysValSerHisLysPheThrIleArgGlyLeuProSerAsnAsn900905910TCGTTGGACTTCCTGGACGAGGAGTATGAGGTGCCTGACCTGGATGGC2964SerLeuAspPheLeuAspGluGluTyrGluValProAspLeuAspGly915920925GCTAGGGCTCCCATCAATGGCTGTTGCAGCCTTGATGCTGAG3006AlaArgAlaProIleAsnGlyCysCysSerLeuAspAlaGlu930935940TGAGTCCCTCCTGGGACCCCTCCCTGTCCAGGCCTCCTCCCACAAGCCTCCACGGGCCTG3066GCCGCACGCCCTGGGACCAGAGCCAAGGGTCCTGGATTCTAGGCCAGGACTTCCCATGTG3126ACCCGGGCGAGGTCTGACCTTCCCGGGCCTCAGCTTTCTTGTCTGTATAATGGAAGACTT3186CAGCCTCACTGAGACTTTGTCACTTGTCCTCTGAGAGCACAGGGGTAACCAATGAGCAGT3246GGACCCTGCTCTGCACCTCTGACCGCATCTTGGCAAGTCCCCACCCTCCAGGCCACTCCT3306TCTCTGAGGCAGCCGGATGGTTTCTTCTGGGCCCCATTCCTGCCCTACCAGACCTGTGCC3366CTTTCCTGTGGGGGCACCCTCACTGGCTCCCAGGATCCTCAGGCAAGAACATGAGACATC3426TGAGTGGGCAAAGGGTGGGTCTTAGAGACAGTTATCAGCCTGGCTGGAGGACTAGAAGTA3486GCCATGGGACCACCTGTGGCCCAGAGGACTGCCTTTGTACTTATGGTGGGGACTGGGACC3546TGGGGATATAAGGGTCCCAGGAGGACACTGCCAGGGGGCCAGTGCAGTGCTCTGGGGAGA3606GGGGGCTCAGGAAGAGAGGAGGATAAGAACAGTGAGAAGGAAGGATCCCTGGGTTGGGAG3666GCAGGCCCAGCATGGGTCAGCCATGCTTCCTCCTGGCTGTGTGACCCTGGGCAAGTCCCT3726TCCCCTCTCTGCGAAACAGTAGGGTGAGACAATCCATTCTCTAAGACCCCTTTTAGATCC3786AAG3789(2) INFORMATION FOR SEQ ID NO:43:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 942 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:43:MetGlyGlnAlaCysGlyHisSerIleLeuCysArgSerGlnGlnTyr151015ProAlaAlaArgProAlaGluProArgGlyGlnGlnValPheLeuLys202530ProAspGluProProProProProGlnProCysAlaAspSerLeuGln354045AspAlaLeuLeuSerLeuGlySerValIleAspValAlaGlyLeuGln505560GlnAlaValLysGluAlaLeuSerAlaValLeuProLysValGluThr65707580ValTyrThrTyrLeuLeuAspGlyGluSerArgLeuValCysGluGlu859095ProProHisGluLeuProGlnGluGlyLysValArgGluAlaValIle100105110SerArgLysArgLeuGlyCysAsnGlyLeuGlyProSerAspLeuPro115120125GlyLysProLeuAlaArgLeuValAlaProLeuAlaProAspThrGln130135140ValLeuValIleProLeuValAspLysGluAlaGlyAlaValAlaAla145150155160ValIleLeuValHisCysGlyGlnLeuSerAspAsnGluGluTrpSer165170175LeuGlnAlaValGluLysHisThrLeuValAlaLeuLysArgValGln180185190AlaLeuGlnGlnArgGluSerSerValAlaProGluAlaThrGlnAsn195200205ProProGluGluAlaAlaGlyAspGlnLysGlyGlyValAlaTyrThr210215220AspGlnAspArgLysIleLeuGlnLeuCysGlyGluLeuTyrAspLeu225230235240AspAlaSerSerLeuGlnLeuLysValLeuGlnTyrLeuGlnGlnGlu245250255ThrGlnAlaSerArgCysCysLeuLeuLeuValSerGluAspAsnLeu260265270GlnLeuSerCysLysValIleGlyAspLysValLeuGluGluGluIle275280285SerPheProLeuThrThrGlyArgLeuGlyGlnValValGluAspLys290295300LysSerIleGlnLeuLysAspLeuThrSerGluAspMetGlnGlnLeu305310315320GlnSerMetLeuGlyCysGluValGlnAlaMetLeuCysValProVal325330335IleSerArgAlaThrAspGlnValValAlaLeuAlaCysAlaPheAsn340345350LysLeuGlyGlyAspLeuPheThrAspGlnAspGluHisValIleGln355360365HisCysPheHisTyrThrSerThrValLeuThrSerThrLeuAlaPhe370375380GlnLysGluGlnLysLeuLysCysGluCysGlnAlaLeuLeuGlnVal385390395400AlaLysAsnLeuPheThrHisLeuAspAspValSerValLeuLeuGln405410415GluIleIleThrGluAlaArgAsnLeuSerAsnAlaGluIleCysSer420425430ValPheLeuLeuAspGlnAsnGluLeuValAlaLysValPheAspGly435440445GlyValValGluAspGluSerTyrGluIleArgIleProAlaAspGln450455460GlyIleAlaGlyHisValAlaThrThrGlyGlnIleLeuAsnIlePro465470475480AspAlaTyrAlaHisProLeuPheTyrArgGlyValAspAspSerThr485490495GlyPheArgThrArgAsnIleLeuCysPheProIleLysAsnGluAsn500505510GlnGluValIleGlyValAlaGluLeuValAsnLysIleAsnGlyPro515520525TrpPheSerLysPheAspGluAspLeuAlaThrAlaPheSerIleTyr530535540CysGlyIleSerIleAlaHisSerLeuLeuTyrLysLysValAsnGlu545550555560AlaGlnTyrArgSerHisLeuAlaAsnGluMetMetMetTyrHisMet565570575LysValSerAspAspGluTyrThrLysLeuLeuHisAspGlyIleGln580585590ProValAlaAlaIleAspSerAsnPheAlaSerPheThrTyrThrPro595600605ArgSerLeuProGluAspAspThrSerMetAlaIleLeuSerMetLeu610615620GlnAspMetAsnPheIleAsnAsnTyrLysIleAspCysProThrLeu625630635640AlaArgPheCysLeuMetValLysLysGlyTyrArgAspProProTyr645650655HisAsnTrpMetHisAlaPheSerValSerHisPheCysTyrLeuLeu660665670TyrLysAsnLeuGluLeuThrAsnTyrLeuGluAspMetGluIlePhe675680685AlaLeuPheIleSerCysMetCysHisAspLeuAspHisArgGlyThr690695700AsnAsnSerPheGlnValAlaSerLysSerValLeuAlaAlaLeuTyr705710715720SerSerGluGlySerValMetGluArgHisHisPheAlaGlnAlaIle725730735AlaIleLeuAsnThrHisGlyCysAsnIlePheAspHisPheSerArg740745750LysAspTyrGlnArgMetLeuAspLeuMetArgAspIleIleLeuAla755760765ThrAspLeuAlaHisHisLeuArgIlePheLysAspLeuGlnLysMet770775780AlaGluValGlyTyrAspArgThrAsnLysGlnHisHisSerLeuLeu785790795800LeuCysLeuLeuMetThrSerCysAspLeuSerAspGlnThrLysGly805810815TrpLysThrThrArgLysIleAlaGluLeuIleTyrLysGluPhePhe820825830SerGlnGlyAspLeuGluLysAlaMetGlyAsnArgProMetGluMet835840845MetAspArgGluLysAlaTyrIleProGluLeuGlnIleSerPheMet850855860GluHisIleAlaMetProIleTyrLysLeuLeuGlnAspLeuPhePro865870875880LysAlaAlaGluLeuTyrGluArgValAlaSerAsnArgGluHisTrp885890895ThrLysValSerHisLysPheThrIleArgGlyLeuProSerAsnAsn900905910SerLeuAspPheLeuAspGluGluTyrGluValProAspLeuAspGly915920925AlaArgAlaProIleAsnGlyCysCysSerLeuAspAlaGlu930935940(2) INFORMATION FOR SEQ ID NO:44:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 3044 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 12..2834(xi) SEQUENCE DESCRIPTION: SEQ ID NO:44:GAATTCTGATAATGGGGCAGGCATGCGGCCACTCCATCCTCTGCAGGAGC50MetGlyGlnAlaCysGlyHisSerIleLeuCysArgSer1510CAGCAGTACCCGGCAGCGCGACCGGCTGAGCCGCGGGGCCAGCAGGTC98GlnGlnTyrProAlaAlaArgProAlaGluProArgGlyGlnGlnVal152025TTCCTCAAGCCGGACGAGCCGCCGCCGCCGCCGCAGCCATGCGCCGAC146PheLeuLysProAspGluProProProProProGlnProCysAlaAsp30354045AGCCTGCAGGACGCCTTGCTGAGTCTGGGCTCTGTCATCGACATTTCA194SerLeuGlnAspAlaLeuLeuSerLeuGlySerValIleAspIleSer505560GGCCTGCAACGTGCTGTCAAGGAGGCCCTGTCAGCTGTGCTCCCCCGA242GlyLeuGlnArgAlaValLysGluAlaLeuSerAlaValLeuProArg657075GTGGAAACTGTCTACACCTACCTACTGGATGGTGAGTCCCAGCTGGTG290ValGluThrValTyrThrTyrLeuLeuAspGlyGluSerGlnLeuVal808590TGTGAGGACCCCCCACATGAGCTGCCCCAGGAGGGGAAAGTCCGGGAG338CysGluAspProProHisGluLeuProGlnGluGlyLysValArgGlu95100105GCTATCATCTCCCAGAAGCGGCTGGGCTGCAATGGGCTGGGCTTCTCA386AlaIleIleSerGlnLysArgLeuGlyCysAsnGlyLeuGlyPheSer110115120125GACCTGCCAGGGAAGCCCTTGGCCAGGCTGGTGGCTCCACTGGCTCCT434AspLeuProGlyLysProLeuAlaArgLeuValAlaProLeuAlaPro130135140GATACCCAAGTGCTGGTCATGCCGCTAGCGGACAAGGAGGCTGGGGCC482AspThrGlnValLeuValMetProLeuAlaAspLysGluAlaGlyAla145150155GTGGCAGCTGTCATCTTGGTGCACTGTGGCCAGCTGAGTGATAATGAG530ValAlaAlaValIleLeuValHisCysGlyGlnLeuSerAspAsnGlu160165170GAATGGAGCCTGCAGGCGGTGGAGAAGCATACCCTGGTCGCCCTGCGG578GluTrpSerLeuGlnAlaValGluLysHisThrLeuValAlaLeuArg175180185AGGGTGCAGGTCCTGCAGCAGCGCGGGCCCAGGGAGGCTCCCCGAGCC626ArgValGlnValLeuGlnGlnArgGlyProArgGluAlaProArgAla190195200205GTCCAGAACCCCCCGGAGGGGACGGCGGAAGACCAGAAGGGCGGGGCG674ValGlnAsnProProGluGlyThrAlaGluAspGlnLysGlyGlyAla210215220GCGTACACCGACCGCGACCGCAAGATCCTCCAACTGTGCGGGGAACTC722AlaTyrThrAspArgAspArgLysIleLeuGlnLeuCysGlyGluLeu225230235TACGACCTGGATGCCTCTTCCCTGCAGCTCAAAGTGCTCCAATACCTG770TyrAspLeuAspAlaSerSerLeuGlnLeuLysValLeuGlnTyrLeu240245250CAGCAGGAGACCCGGGCATCCCGCTGCTGCCTCCTGCTGGTGTCGGAG818GlnGlnGluThrArgAlaSerArgCysCysLeuLeuLeuValSerGlu255260265GACAATCTCCAGCTTTCTTGCAAGGTCATCGGAGACAAAGTGCTCGGG866AspAsnLeuGlnLeuSerCysLysValIleGlyAspLysValLeuGly270275280285GAAGAGGTCAGCTTTCCCTTGACAGGATGCCTGGGCCAGGTGGTGGAA914GluGluValSerPheProLeuThrGlyCysLeuGlyGlnValValGlu290295300GACAAGAAGTCCATCCAGCTGAAGGACCTCACCTCCGAGGATGTACAA962AspLysLysSerIleGlnLeuLysAspLeuThrSerGluAspValGln305310315CAGCTGCAGAGCATGTTGGGCTGTGAGCTGCAGGCCATGCTCTGTGTC1010GlnLeuGlnSerMetLeuGlyCysGluLeuGlnAlaMetLeuCysVal320325330CCTGTCATCAGCCGGGCCACTGACCAGGTGGTGGCCTTGGCCTGCGCC1058ProValIleSerArgAlaThrAspGlnValValAlaLeuAlaCysAla335340345TTCAACAAGCTAGAAGGAGACTTGTTCACCGACGAGGACGAGCATGTG1106PheAsnLysLeuGluGlyAspLeuPheThrAspGluAspGluHisVal350355360365ATCCAGCACTGCTTCCACTACACCAGCACCGTGCTCACCAGCACCCTG1154IleGlnHisCysPheHisTyrThrSerThrValLeuThrSerThrLeu370375380GCCTTCCAGAAGGAACAGAAACTCAAGTGTGAGTGCCAGGCTCTTCTC1202AlaPheGlnLysGluGlnLysLeuLysCysGluCysGlnAlaLeuLeu385390395CAAGTGGCAAAGAACCTCTTCACCCACCTGGATGACGTCTCTGTCCTG1250GlnValAlaLysAsnLeuPheThrHisLeuAspAspValSerValLeu400405410CTCCAGGAGATCATCACGGAGGCCAGAAACCTCAGCAACGCAGAGATC1298LeuGlnGluIleIleThrGluAlaArgAsnLeuSerAsnAlaGluIle415420425TGCTCTGTGTTCCTGCTGGATCAGAATGAGCTGGTGGCCAAGGTGTTC1346CysSerValPheLeuLeuAspGlnAsnGluLeuValAlaLysValPhe430435440445GACGGGGGCGTGGTGGATGATGAGAGCTATGAGATCCGCATCCCGGCC1394AspGlyGlyValValAspAspGluSerTyrGluIleArgIleProAla450455460GATCAGGGCATCGCGGGACACGTGGCGACCACGGGCCAGATCCTGAAC1442AspGlnGlyIleAlaGlyHisValAlaThrThrGlyGlnIleLeuAsn465470475ATCCCTGACGCATATGCCCATCCGCTTTTCTACCGCGGCGTGGACGAC1490IleProAspAlaTyrAlaHisProLeuPheTyrArgGlyValAspAsp480485490AGCACCGGCTTCCGCACGCGCAACATCCTCTGCTTCCCCATCAAGAAC1538SerThrGlyPheArgThrArgAsnIleLeuCysPheProIleLysAsn495500505GAGAACCAGGAGGTCATCGGTGTGGCCGAGCTGGTGAACAAGATCAAT1586GluAsnGlnGluValIleGlyValAlaGluLeuValAsnLysIleAsn510515520525GGGCCATGGTTCAGCAAGTTCGACGAGGACCTGGCGACGGCCTTCTCC1634GlyProTrpPheSerLysPheAspGluAspLeuAlaThrAlaPheSer530535540ATCTACTGCGGCATCAGCATCGCCCATTCTCTCCTATACAAAAAAGTG1682IleTyrCysGlyIleSerIleAlaHisSerLeuLeuTyrLysLysVal545550555AATGAGGCTCAGTATCGCAGCCACCTGGCCAATGAGATGATGATGTAC1730AsnGluAlaGlnTyrArgSerHisLeuAlaAsnGluMetMetMetTyr560565570CACATGAAGGTCTCCGACGATGAGTATACCAAACTTCTCCATGATGGG1778HisMetLysValSerAspAspGluTyrThrLysLeuLeuHisAspGly575580585ATCCAGCCTGTGGCTGCCATTGACTCCAATTTTGCAAGTTTCACCTAT1826IleGlnProValAlaAlaIleAspSerAsnPheAlaSerPheThrTyr590595600605ACCCCTCGTTCCCTGCCCGAGGATGACACGTCCATGGCCATCCTGAGC1874ThrProArgSerLeuProGluAspAspThrSerMetAlaIleLeuSer610615620ATGCTGCAGGACATGAATTTCATCAACAACTACAAAATTGACTGCCCG1922MetLeuGlnAspMetAsnPheIleAsnAsnTyrLysIleAspCysPro625630635ACCCTGGCCCGGTTCTGTTTGATGGTGAAGAAGGGCTACCGGGATCCC1970ThrLeuAlaArgPheCysLeuMetValLysLysGlyTyrArgAspPro640645650CCCTACCACAACTGGATGCACGCCTTTTCTGTCTCCCACTTCTGCTAC2018ProTyrHisAsnTrpMetHisAlaPheSerValSerHisPheCysTyr655660665CTGCTCTACAAGAACCTGGAGCTCACCAACTACCTCGAGGACATCGAG2066LeuLeuTyrLysAsnLeuGluLeuThrAsnTyrLeuGluAspIleGlu670675680685ATCTTTGCCTTGTTTATTTCCTGCATGTGTCATGACCTGGACCACAGA2114IlePheAlaLeuPheIleSerCysMetCysHisAspLeuAspHisArg690695700GGCACAAACAACTCTTTCCAGGTGGCCTCGAAATCTGTGCTGGCTGCG2162GlyThrAsnAsnSerPheGlnValAlaSerLysSerValLeuAlaAla705710715CTCTACAGCTCTGAGGGCTCCGTCATGGAGAGGCACCACTTTGCTCAG2210LeuTyrSerSerGluGlySerValMetGluArgHisHisPheAlaGln720725730GCCATCGCCATCCTCAACACCCACGGCTGCAACATCTTTGATCATTTC2258AlaIleAlaIleLeuAsnThrHisGlyCysAsnIlePheAspHisPhe735740745TCCCGGAAGGACTATCAGCGCATGCTGGATCTGATGCGGGACATCATC2306SerArgLysAspTyrGlnArgMetLeuAspLeuMetArgAspIleIle750755760765TTGGCCACAGACCTGGCCCACCATCTCCGCATCTTCAAGGACCTCCAG2354LeuAlaThrAspLeuAlaHisHisLeuArgIlePheLysAspLeuGln770775780AAGATGGCTGAGGTGGGCTACGACCGAAACAACAAGCAGCACCACAGA2402LysMetAlaGluValGlyTyrAspArgAsnAsnLysGlnHisHisArg785790795CTTCTCCTCTGCCTCCTCATGACCTCCTGTGACCTCTCTGACCAGACC2450LeuLeuLeuCysLeuLeuMetThrSerCysAspLeuSerAspGlnThr800805810AAGGGCTGGAAGACTACGAGAAAGATCGCGGAGCTGATCTACAAAGAA2498LysGlyTrpLysThrThrArgLysIleAlaGluLeuIleTyrLysGlu815820825TTCTTCTCCCAGGGAGACCTGGAGAAGGCCATGGGCAACAGGCCGATG2546PhePheSerGlnGlyAspLeuGluLysAlaMetGlyAsnArgProMet830835840845GAGATGATGGACCGGGAGAAGGCCTATATCCCTGAGCTGCAAATCAGC2594GluMetMetAspArgGluLysAlaTyrIleProGluLeuGlnIleSer850855860TTCATGGAGCACATTGCAATGCCCATCTACAAGCTGTTGCAGGACCTG2642PheMetGluHisIleAlaMetProIleTyrLysLeuLeuGlnAspLeu865870875TTCCCCAAAGCGGCAGAGCTGTACGAGCGCGTGGCCTCCAACCGTGAG2690PheProLysAlaAlaGluLeuTyrGluArgValAlaSerAsnArgGlu880885890CACTGGACCAAGGTGTCCCACAAGTTCACCATCCGCGGCCTCCCAAGT2738HisTrpThrLysValSerHisLysPheThrIleArgGlyLeuProSer895900905AACAACTCGCTGGACTTCCTGGATGAGGAGTACGAGGTGCCTGATCTG2786AsnAsnSerLeuAspPheLeuAspGluGluTyrGluValProAspLeu910915920925GATGGCACTAGGGCCCCCATCAATGGCTGCTGCAGCCTTGATGCTGAG2834AspGlyThrArgAlaProIleAsnGlyCysCysSerLeuAspAlaGlu930935940TGACTCGAGCGTCATATTAATGGACGCAAAGCAAGGAAATTGCGAGCGGGAAATAAGAAA2894CGATAGAAGTAGGAATCGATACCCGGTGCGTGCACATAACAGTCTTTTACCAATTAACAG2954GAGAGATTGAAGTGTCGAGATACGAAATGAAATTTACTACGACTACCGTAAAGAAATGCA3014TAAGCTCTGTTAGAGAAAAATTGGTAGCCA3044(2) INFORMATION FOR SEQ ID NO:45:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 941 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:45:MetGlyGlnAlaCysGlyHisSerIleLeuCysArgSerGlnGlnTyr151015ProAlaAlaArgProAlaGluProArgGlyGlnGlnValPheLeuLys202530ProAspGluProProProProProGlnProCysAlaAspSerLeuGln354045AspAlaLeuLeuSerLeuGlySerValIleAspIleSerGlyLeuGln505560ArgAlaValLysGluAlaLeuSerAlaValLeuProArgValGluThr65707580ValTyrThrTyrLeuLeuAspGlyGluSerGlnLeuValCysGluAsp859095ProProHisGluLeuProGlnGluGlyLysValArgGluAlaIleIle100105110SerGlnLysArgLeuGlyCysAsnGlyLeuGlyPheSerAspLeuPro115120125GlyLysProLeuAlaArgLeuValAlaProLeuAlaProAspThrGln130135140ValLeuValMetProLeuAlaAspLysGluAlaGlyAlaValAlaAla145150155160ValIleLeuValHisCysGlyGlnLeuSerAspAsnGluGluTrpSer165170175LeuGlnAlaValGluLysHisThrLeuValAlaLeuArgArgValGln180185190ValLeuGlnGlnArgGlyProArgGluAlaProArgAlaValGlnAsn195200205ProProGluGlyThrAlaGluAspGlnLysGlyGlyAlaAlaTyrThr210215220AspArgAspArgLysIleLeuGlnLeuCysGlyGluLeuTyrAspLeu225230235240AspAlaSerSerLeuGlnLeuLysValLeuGlnTyrLeuGlnGlnGlu245250255ThrArgAlaSerArgCysCysLeuLeuLeuValSerGluAspAsnLeu260265270GlnLeuSerCysLysValIleGlyAspLysValLeuGlyGluGluVal275280285SerPheProLeuThrGlyCysLeuGlyGlnValValGluAspLysLys290295300SerIleGlnLeuLysAspLeuThrSerGluAspValGlnGlnLeuGln305310315320SerMetLeuGlyCysGluLeuGlnAlaMetLeuCysValProValIle325330335SerArgAlaThrAspGlnValValAlaLeuAlaCysAlaPheAsnLys340345350LeuGluGlyAspLeuPheThrAspGluAspGluHisValIleGlnHis355360365CysPheHisTyrThrSerThrValLeuThrSerThrLeuAlaPheGln370375380LysGluGlnLysLeuLysCysGluCysGlnAlaLeuLeuGlnValAla385390395400LysAsnLeuPheThrHisLeuAspAspValSerValLeuLeuGlnGlu405410415IleIleThrGluAlaArgAsnLeuSerAsnAlaGluIleCysSerVal420425430PheLeuLeuAspGlnAsnGluLeuValAlaLysValPheAspGlyGly435440445ValValAspAspGluSerTyrGluIleArgIleProAlaAspGlnGly450455460IleAlaGlyHisValAlaThrThrGlyGlnIleLeuAsnIleProAsp465470475480AlaTyrAlaHisProLeuPheTyrArgGlyValAspAspSerThrGly485490495PheArgThrArgAsnIleLeuCysPheProIleLysAsnGluAsnGln500505510GluValIleGlyValAlaGluLeuValAsnLysIleAsnGlyProTrp515520525PheSerLysPheAspGluAspLeuAlaThrAlaPheSerIleTyrCys530535540GlyIleSerIleAlaHisSerLeuLeuTyrLysLysValAsnGluAla545550555560GlnTyrArgSerHisLeuAlaAsnGluMetMetMetTyrHisMetLys565570575ValSerAspAspGluTyrThrLysLeuLeuHisAspGlyIleGlnPro580585590ValAlaAlaIleAspSerAsnPheAlaSerPheThrTyrThrProArg595600605SerLeuProGluAspAspThrSerMetAlaIleLeuSerMetLeuGln610615620AspMetAsnPheIleAsnAsnTyrLysIleAspCysProThrLeuAla625630635640ArgPheCysLeuMetValLysLysGlyTyrArgAspProProTyrHis645650655AsnTrpMetHisAlaPheSerValSerHisPheCysTyrLeuLeuTyr660665670LysAsnLeuGluLeuThrAsnTyrLeuGluAspIleGluIlePheAla675680685LeuPheIleSerCysMetCysHisAspLeuAspHisArgGlyThrAsn690695700AsnSerPheGlnValAlaSerLysSerValLeuAlaAlaLeuTyrSer705710715720SerGluGlySerValMetGluArgHisHisPheAlaGlnAlaIleAla725730735IleLeuAsnThrHisGlyCysAsnIlePheAspHisPheSerArgLys740745750AspTyrGlnArgMetLeuAspLeuMetArgAspIleIleLeuAlaThr755760765AspLeuAlaHisHisLeuArgIlePheLysAspLeuGlnLysMetAla770775780GluValGlyTyrAspArgAsnAsnLysGlnHisHisArgLeuLeuLeu785790795800CysLeuLeuMetThrSerCysAspLeuSerAspGlnThrLysGlyTrp805810815LysThrThrArgLysIleAlaGluLeuIleTyrLysGluPhePheSer820825830GlnGlyAspLeuGluLysAlaMetGlyAsnArgProMetGluMetMet835840845AspArgGluLysAlaTyrIleProGluLeuGlnIleSerPheMetGlu850855860HisIleAlaMetProIleTyrLysLeuLeuGlnAspLeuPheProLys865870875880AlaAlaGluLeuTyrGluArgValAlaSerAsnArgGluHisTrpThr885890895LysValSerHisLysPheThrIleArgGlyLeuProSerAsnAsnSer900905910LeuAspPheLeuAspGluGluTyrGluValProAspLeuAspGlyThr915920925ArgAlaProIleAsnGlyCysCysSerLeuAspAlaGlu930935940(2) INFORMATION FOR SEQ ID NO:46:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 23 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(iv) ANTI-SENSE: YES(xi) SEQUENCE DESCRIPTION: SEQ ID NO:46:TCRTTNGTNGTNCCYTTCATRTT23(2) INFORMATION FOR SEQ ID NO:47:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 8 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: peptide(xi) SEQUENCE DESCRIPTION: SEQ ID NO:47:AsnMetLysGlyThrThrAsnAsp15(2) INFORMATION FOR SEQ ID NO:48:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 1625 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 12..1616(xi) SEQUENCE DESCRIPTION: SEQ ID NO:48:GAATTCTGATCATGGGGTCTAGTGCCACAGAGATTGAAGAATTGGAAAAC50MetGlySerSerAlaThrGluIleGluGluLeuGluAsn1510ACCACTTTTAAGTATCTTACAGGAGAACAGACTGAAAAAATGTGGCAG98ThrThrPheLysTyrLeuThrGlyGluGlnThrGluLysMetTrpGln152025CGCCTGAAAGGAATACTAAGATGCTTGGTGAAGCAGCTGGAAAGAGGT146ArgLeuLysGlyIleLeuArgCysLeuValLysGlnLeuGluArgGly30354045GATGTTAACGTCGTCGACTTAAAGAAGAATATTGAATATGCGGCATCT194AspValAsnValValAspLeuLysLysAsnIleGluTyrAlaAlaSer505560GTGCTGGAAGCAGTTTATATCGATGAAACAAGAAGACTTCTGGATACT242ValLeuGluAlaValTyrIleAspGluThrArgArgLeuLeuAspThr657075GAAGATGAGCTCAGTGACATTCAGACTGACTCAGTCCCATCTGAAGTC290GluAspGluLeuSerAspIleGlnThrAspSerValProSerGluVal808590CGGGACTGGTTGGCTTCTACCTTTACACGGAAAATGGGGATGACAAAA338ArgAspTrpLeuAlaSerThrPheThrArgLysMetGlyMetThrLys95100105AAGAAACCTGAGGAAAAACCAAAATTTCGGAGCATTGTGCATGCTGTT386LysLysProGluGluLysProLysPheArgSerIleValHisAlaVal110115120125CAAGCTGGAATTTTTGTGGAAAGAATGTACCGAAAAACATATCATATG434GlnAlaGlyIlePheValGluArgMetTyrArgLysThrTyrHisMet130135140GTTGGTTTGGCATATCCAGCAGCTGTCATCGTAACATTAAAGGATGTT482ValGlyLeuAlaTyrProAlaAlaValIleValThrLeuLysAspVal145150155GATAAATGGTCTTTCGATGTATTTGCCCTAAATGAAGCAAGTGGAGAG530AspLysTrpSerPheAspValPheAlaLeuAsnGluAlaSerGlyGlu160165170CATAGTCTGAAGTTTATGATTTATGAACTGTTTACCAGATATGATCTT578HisSerLeuLysPheMetIleTyrGluLeuPheThrArgTyrAspLeu175180185ATCAACCGTTTCAAGATTCCTGTTTCTTGCCTAATCACCTTTGCAGAA626IleAsnArgPheLysIleProValSerCysLeuIleThrPheAlaGlu190195200205GCTTTAGAAGTTGGTTACAGCAAGTACAAAAATCCATATCACAATTTG674AlaLeuGluValGlyTyrSerLysTyrLysAsnProTyrHisAsnLeu210215220ATTCATGCAGCTGATGTCACTCAAACTGTGCATTACATAATGCTTCAT722IleHisAlaAlaAspValThrGlnThrValHisTyrIleMetLeuHis225230235ACAGGTATCATGCACTGGCTCACTGAACTGGAAATTTTAGCAATGGTC770ThrGlyIleMetHisTrpLeuThrGluLeuGluIleLeuAlaMetVal240245250TTTGCTGCTGCCATTCATGATTATGAGCATACAGGGACAACAAACAAC818PheAlaAlaAlaIleHisAspTyrGluHisThrGlyThrThrAsnAsn255260265TTTCACATTCAGACAAGGTCAGATGTTGCCATTTTGTATAATGATCGC866PheHisIleGlnThrArgSerAspValAlaIleLeuTyrAsnAspArg270275280285TCTGTCCTTGAGAATCACCACGTGAGTGCAGCTTATCGACTTATGCAA914SerValLeuGluAsnHisHisValSerAlaAlaTyrArgLeuMetGln290295300GAAGAAGAAATGAATATCTTGATAAATTTATCCAAAGATGACTGGAGG962GluGluGluMetAsnIleLeuIleAsnLeuSerLysAspAspTrpArg305310315GATCTTCGGAACCTAGTGATTGAAATGGTTTTATCTACAGACATGTCA1010AspLeuArgAsnLeuValIleGluMetValLeuSerThrAspMetSer320325330GGTCACTTCCAGCAAATTAAAAATATAAGAAACAGTTTGCAGCAGCCT1058GlyHisPheGlnGlnIleLysAsnIleArgAsnSerLeuGlnGlnPro335340345GAAGGGATTGACAGAGCCAAAACCATGTCCCTGATTCTCCACGCAGCA1106GluGlyIleAspArgAlaLysThrMetSerLeuIleLeuHisAlaAla350355360365GACATCAGCCACCCAGCCAAATCCTGGAAGCTGCATTATCGGTGGACC1154AspIleSerHisProAlaLysSerTrpLysLeuHisTyrArgTrpThr370375380ATGGCCCTAATGGAGGAGTTTTTCCTGCAGGGAGATAAAGAAGCTGAA1202MetAlaLeuMetGluGluPhePheLeuGlnGlyAspLysGluAlaGlu385390395TTAGGGCTTCCATTTTCCCCACTTTGTGATCGGAAGTCAACCATGGTG1250LeuGlyLeuProPheSerProLeuCysAspArgLysSerThrMetVal400405410GCCCAGTCACAAATAGGTTTCATCGATTTCATAGTAGAGCCAACATTT1298AlaGlnSerGlnIleGlyPheIleAspPheIleValGluProThrPhe415420425TCTCTTCTGACAGACTCAACAGAGAAAATTGTTATTCCTCTTATAGAG1346SerLeuLeuThrAspSerThrGluLysIleValIleProLeuIleGlu430435440445GAAGCCTCAAAAGCCGAAACTTCTTCCTATGTGGCAAGCAGCTCAACC1394GluAlaSerLysAlaGluThrSerSerTyrValAlaSerSerSerThr450455460ACCATTGTGGGGTTACACATTGCTGATGCACTAAGACGATCAAATACA1442ThrIleValGlyLeuHisIleAlaAspAlaLeuArgArgSerAsnThr465470475AAAGGCTCCATGAGTGATGGGTCCTATTCCCCAGACTACTCCCTTGCA1490LysGlySerMetSerAspGlySerTyrSerProAspTyrSerLeuAla480485490GCAGTGGACCTGAAGAGTTTCAAGAACAACCTGGTGGACATCATTCAG1538AlaValAspLeuLysSerPheLysAsnAsnLeuValAspIleIleGln495500505CAGAACAAAGAGAGGTGGAAAGAGTTAGCTGCACAAGAAGCAAGAACC1586GlnAsnLysGluArgTrpLysGluLeuAlaAlaGlnGluAlaArgThr510515520525AGTTCACAGAAGTGTGAGTTTATTCATCAGTAACTCGAG1625SerSerGlnLysCysGluPheIleHisGln530535(2) INFORMATION FOR SEQ ID NO:49:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 535 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:49:MetGlySerSerAlaThrGluIleGluGluLeuGluAsnThrThrPhe151015LysTyrLeuThrGlyGluGlnThrGluLysMetTrpGlnArgLeuLys202530GlyIleLeuArgCysLeuValLysGlnLeuGluArgGlyAspValAsn354045ValValAspLeuLysLysAsnIleGluTyrAlaAlaSerValLeuGlu505560AlaValTyrIleAspGluThrArgArgLeuLeuAspThrGluAspGlu65707580LeuSerAspIleGlnThrAspSerValProSerGluValArgAspTrp859095LeuAlaSerThrPheThrArgLysMetGlyMetThrLysLysLysPro100105110GluGluLysProLysPheArgSerIleValHisAlaValGlnAlaGly115120125IlePheValGluArgMetTyrArgLysThrTyrHisMetValGlyLeu130135140AlaTyrProAlaAlaValIleValThrLeuLysAspValAspLysTrp145150155160SerPheAspValPheAlaLeuAsnGluAlaSerGlyGluHisSerLeu165170175LysPheMetIleTyrGluLeuPheThrArgTyrAspLeuIleAsnArg180185190PheLysIleProValSerCysLeuIleThrPheAlaGluAlaLeuGlu195200205ValGlyTyrSerLysTyrLysAsnProTyrHisAsnLeuIleHisAla210215220AlaAspValThrGlnThrValHisTyrIleMetLeuHisThrGlyIle225230235240MetHisTrpLeuThrGluLeuGluIleLeuAlaMetValPheAlaAla245250255AlaIleHisAspTyrGluHisThrGlyThrThrAsnAsnPheHisIle260265270GlnThrArgSerAspValAlaIleLeuTyrAsnAspArgSerValLeu275280285GluAsnHisHisValSerAlaAlaTyrArgLeuMetGlnGluGluGlu290295300MetAsnIleLeuIleAsnLeuSerLysAspAspTrpArgAspLeuArg305310315320AsnLeuValIleGluMetValLeuSerThrAspMetSerGlyHisPhe325330335GlnGlnIleLysAsnIleArgAsnSerLeuGlnGlnProGluGlyIle340345350AspArgAlaLysThrMetSerLeuIleLeuHisAlaAlaAspIleSer355360365HisProAlaLysSerTrpLysLeuHisTyrArgTrpThrMetAlaLeu370375380MetGluGluPhePheLeuGlnGlyAspLysGluAlaGluLeuGlyLeu385390395400ProPheSerProLeuCysAspArgLysSerThrMetValAlaGlnSer405410415GlnIleGlyPheIleAspPheIleValGluProThrPheSerLeuLeu420425430ThrAspSerThrGluLysIleValIleProLeuIleGluGluAlaSer435440445LysAlaGluThrSerSerTyrValAlaSerSerSerThrThrIleVal450455460GlyLeuHisIleAlaAspAlaLeuArgArgSerAsnThrLysGlySer465470475480MetSerAspGlySerTyrSerProAspTyrSerLeuAlaAlaValAsp485490495LeuLysSerPheLysAsnAsnLeuValAspIleIleGlnGlnAsnLys500505510GluArgTrpLysGluLeuAlaAlaGlnGluAlaArgThrSerSerGln515520525LysCysGluPheIleHisGln530535(2) INFORMATION FOR SEQ ID NO:50:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2693 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 176..2077(xi) SEQUENCE DESCRIPTION: SEQ ID NO:50:GTCGCTTCAATATTTCAAAATGGATCCGGTTCTGTGGCGGGTGCGAGAGTGAGGCTGTGG60GGGACCTCCAGGCCGAACCTCCGCGAAGCCTCGGCCTTCTGCGTGCCCTGGCCCCGGGAG120GATAAGGATTTCCCTTCCCTCCTACTTGCGCGCGGAGCCGAGCTCTTGTTGAGCTATG178Met1GAGTCGCCAACCAAGGAGATTGAAGAATTTGAGAGCAACTCTCTGAAA226GluSerProThrLysGluIleGluGluPheGluSerAsnSerLeuLys51015TACCTGCAACCGGAACAGATCGAGAAAATCTGGCTTCGGCTCCGCGGG274TyrLeuGlnProGluGlnIleGluLysIleTrpLeuArgLeuArgGly202530CTGAGGAAATATAAGAAAACGTCCCAGAGATTACGGTCTTTGGTCAAA322LeuArgLysTyrLysLysThrSerGlnArgLeuArgSerLeuValLys354045CAATTAGAGAGAGGGGAAGCTTCAGTGGTAGATCTTAAGAAGAATTTG370GlnLeuGluArgGlyGluAlaSerValValAspLeuLysLysAsnLeu50556065GAATATGCAGCCACAGTGCTTGAATCTGTGTATATTGATGAAACAAGG418GluTyrAlaAlaThrValLeuGluSerValTyrIleAspGluThrArg707580AGACTCCTGGATACAGAGGATGAGCTCAGTGACATTCAGTCAGATGCT466ArgLeuLeuAspThrGluAspGluLeuSerAspIleGlnSerAspAla859095GTGCCTTCTGAGGTCCGAGACTGGCTGGCCTCCACCTTCACGCGGCAG514ValProSerGluValArgAspTrpLeuAlaSerThrPheThrArgGln100105110ATGGGGATGATGCTCAGGAGGAGCGACGAGAAGCCCCGGTTCAAGAGC562MetGlyMetMetLeuArgArgSerAspGluLysProArgPheLysSer115120125ATCGTTCACGCAGTGCAGGCTGGGATATTTGTGGAGAGAATGTATAGA610IleValHisAlaValGlnAlaGlyIlePheValGluArgMetTyrArg130135140145CGGACATCAAACATGGTTGGACTGAGCTATCCACCAGCTGTTATTGAG658ArgThrSerAsnMetValGlyLeuSerTyrProProAlaValIleGlu150155160GCATTAAAGGATGTGGACAAGTGGTCCTTTGACGTCTTTTCCCTCAAT706AlaLeuLysAspValAspLysTrpSerPheAspValPheSerLeuAsn165170175GAGGCCAGTGGGGATCATGCACTGAAATTTATTTTCTATGAACTACTC754GluAlaSerGlyAspHisAlaLeuLysPheIlePheTyrGluLeuLeu180185190ACACGTTATGATCTGATCAGCCGTTTCAAGATCCCCATTTCTGCACTT802ThrArgTyrAspLeuIleSerArgPheLysIleProIleSerAlaLeu195200205GTCTCATTTGTGGAGGCCCTGGAAGTGGGATACAGCAAGCACAAAAAT850ValSerPheValGluAlaLeuGluValGlyTyrSerLysHisLysAsn210215220225CCTTACCATAACTTAATGCACGCTGCCGATGTTACACAGACAGTGCAT898ProTyrHisAsnLeuMetHisAlaAlaAspValThrGlnThrValHis230235240TACCTCCTCTATAAGACAGGAGTGGCGAACTGGCTGACGGAGCTGGAG946TyrLeuLeuTyrLysThrGlyValAlaAsnTrpLeuThrGluLeuGlu245250255ATCTTTGCTATAATCTTCTCAGCTGCCATCCATGACTACGAGCATACC994IlePheAlaIleIlePheSerAlaAlaIleHisAspTyrGluHisThr260265270GGAACCACCAACAATTTCCACATTCAGACTCGGTCTGATCCAGCTATT1042GlyThrThrAsnAsnPheHisIleGlnThrArgSerAspProAlaIle275280285CTGTATAATGACAGATCTGTACTGGAGAATCACCATTTAAGTGCAGCT1090LeuTyrAsnAspArgSerValLeuGluAsnHisHisLeuSerAlaAla290295300305TATCGCCTTCTGCAAGATGACGAGGAAATGAATATTTTGATTAACCTC1138TyrArgLeuLeuGlnAspAspGluGluMetAsnIleLeuIleAsnLeu310315320TCAAAGGATGACTGGAGGGAGTTTCGAACCTTGGTAATTGAAATGGTG1186SerLysAspAspTrpArgGluPheArgThrLeuValIleGluMetVal325330335ATGGCCACAGATATGTCTTGTCACTTCCAACAAATCAAAGCAATGAAG1234MetAlaThrAspMetSerCysHisPheGlnGlnIleLysAlaMetLys340345350ACTGCTCTGCAGCAGCCAGAAGCCATTGAAAAGCCAAAAGCCTTATCC1282ThrAlaLeuGlnGlnProGluAlaIleGluLysProLysAlaLeuSer355360365CTTATGCTGCATACAGCAGATATTAGCCATCCAGCAAAAGCATGGGAC1330LeuMetLeuHisThrAlaAspIleSerHisProAlaLysAlaTrpAsp370375380385CTCCATCATCGCTGGACAATGTCACTCCTGGAGGAGTTCTTCAGACAG1378LeuHisHisArgTrpThrMetSerLeuLeuGluGluPhePheArgGln390395400GGTGACAGAGAAGCAGAGCTGGGGCTGCCTTTTTCTCCTCTGTGTGAC1426GlyAspArgGluAlaGluLeuGlyLeuProPheSerProLeuCysAsp405410415CGAAAGTCCACTATGGTTGCTCAGTCACAAGTAGGTTTCATTGATTTC1474ArgLysSerThrMetValAlaGlnSerGlnValGlyPheIleAspPhe420425430ATCGTGGAACCCACCTTCACTGTGCTTACGGACATGACCGAGAAGATT1522IleValGluProThrPheThrValLeuThrAspMetThrGluLysIle435440445GTGAGTCCATTAATCGATGAAACCTCTCAAACTGGTGGGACAGGACAG1570ValSerProLeuIleAspGluThrSerGlnThrGlyGlyThrGlyGln450455460465AGGCGTTCGAGTTTGAATAGCATCAGCTCGTCAGATGCCAAGCGATCA1618ArgArgSerSerLeuAsnSerIleSerSerSerAspAlaLysArgSer470475480GGTGTCAAGACCTCTGGTTCAGAGGGAAGTGCCCCGATCAACAATTCT1666GlyValLysThrSerGlySerGluGlySerAlaProIleAsnAsnSer485490495GTCATCTCCGTTGACTATAAGAGCTTTAAAGCTACTTGGACGGAAGTG1714ValIleSerValAspTyrLysSerPheLysAlaThrTrpThrGluVal500505510GTGCACATCAATCGGGAGAGATGGAGGGCCAAGGTACCCAAAGAGGAG1762ValHisIleAsnArgGluArgTrpArgAlaLysValProLysGluGlu515520525AAGGCCAAGAAGGAAGCAGAGGAAAAGGCTCGCCTGGCCGCAGAGGAG1810LysAlaLysLysGluAlaGluGluLysAlaArgLeuAlaAlaGluGlu530535540545CAGCAAAAGGAAATGGAAGCCAAAAGCCAGGCTGAAGAAGGCGCATCT1858GlnGlnLysGluMetGluAlaLysSerGlnAlaGluGluGlyAlaSer550555560GGCAAAGCTGAGAAAAAGACGTCTGGAGAAACTAAGAATCAAGTCAAT1906GlyLysAlaGluLysLysThrSerGlyGluThrLysAsnGlnValAsn565570575GGAACACGGGCAAACAAAAGTGACAACCCTCGTGGGAAAAATTCCAAA1954GlyThrArgAlaAsnLysSerAspAsnProArgGlyLysAsnSerLys580585590GCCGAGAAGTCATCAGGAGAACAGCAACAGAATGGTGACTTCAAAGAT2002AlaGluLysSerSerGlyGluGlnGlnGlnAsnGlyAspPheLysAsp595600605GGTAAAAATAAGACAGACAAGAAGGATCACTCTAACATCGGAAATGAT2050GlyLysAsnLysThrAspLysLysAspHisSerAsnIleGlyAsnAsp610615620625TCAAAGAAAACAGATGATTCACAAGAGTAAAAAAGACCTCATAGACA2097SerLysLysThrAspAspSerGlnGlu630ATAAAAGAGGCTGCCAGTGTCTTGCATCATTCTAGCTGAGCTTCTTCATTCTCCTTCTTC2157TCCTTCTTCCACAAAGACCCATATCTGGAGAAGGTGTACAACTTTCAAACACAAGCCCCC2217CACCCCCTGACCCTTGGCCTTCCCTCACACCATCTCCTTCCAGGGGATGAATCTTTGGGG2277GTTGGTTTGAGGTCTTAGAACTCTGGGGGATATTCCCCTGAGCAAAACAAACAACGTGAG2337ATTTTTACTCAAACAGAAACAAAACATGAAGGGGCATCCTCAAAATCCTTTGCTAATGAC2397CTGGCTTTCAAGGCATCTGTCTGGCCTGATGAGAATGGACATCCTGGATATGCTGGGAGA2457GGCCTGAAAAAAGCCACACACACAGTAATTGCCATTTTATGACTGTCAATGCCGTTACTT2517TAAATGTTGTCATTTTTGCACTGGCTACTGATGATACAGCCATGCTGACATTCATCACCG2577CAAAGATGATGATTCCAGTCTCTGGTTCCTTTCCTGAGTCAGGAACATTTGTTTTCTCCA2637ATTTCCTTTCAGACTTAAAATTGTTCTTATGCTTTTTTTCCCACTTCTGTAATACA2693(2) INFORMATION FOR SEQ ID NO:51:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 634 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:51:MetGluSerProThrLysGluIleGluGluPheGluSerAsnSerLeu151015LysTyrLeuGlnProGluGlnIleGluLysIleTrpLeuArgLeuArg202530GlyLeuArgLysTyrLysLysThrSerGlnArgLeuArgSerLeuVal354045LysGlnLeuGluArgGlyGluAlaSerValValAspLeuLysLysAsn505560LeuGluTyrAlaAlaThrValLeuGluSerValTyrIleAspGluThr65707580ArgArgLeuLeuAspThrGluAspGluLeuSerAspIleGlnSerAsp859095AlaValProSerGluValArgAspTrpLeuAlaSerThrPheThrArg100105110GlnMetGlyMetMetLeuArgArgSerAspGluLysProArgPheLys115120125SerIleValHisAlaValGlnAlaGlyIlePheValGluArgMetTyr130135140ArgArgThrSerAsnMetValGlyLeuSerTyrProProAlaValIle145150155160GluAlaLeuLysAspValAspLysTrpSerPheAspValPheSerLeu165170175AsnGluAlaSerGlyAspHisAlaLeuLysPheIlePheTyrGluLeu180185190LeuThrArgTyrAspLeuIleSerArgPheLysIleProIleSerAla195200205LeuValSerPheValGluAlaLeuGluValGlyTyrSerLysHisLys210215220AsnProTyrHisAsnLeuMetHisAlaAlaAspValThrGlnThrVal225230235240HisTyrLeuLeuTyrLysThrGlyValAlaAsnTrpLeuThrGluLeu245250255GluIlePheAlaIleIlePheSerAlaAlaIleHisAspTyrGluHis260265270ThrGlyThrThrAsnAsnPheHisIleGlnThrArgSerAspProAla275280285IleLeuTyrAsnAspArgSerValLeuGluAsnHisHisLeuSerAla290295300AlaTyrArgLeuLeuGlnAspAspGluGluMetAsnIleLeuIleAsn305310315320LeuSerLysAspAspTrpArgGluPheArgThrLeuValIleGluMet325330335ValMetAlaThrAspMetSerCysHisPheGlnGlnIleLysAlaMet340345350LysThrAlaLeuGlnGlnProGluAlaIleGluLysProLysAlaLeu355360365SerLeuMetLeuHisThrAlaAspIleSerHisProAlaLysAlaTrp370375380AspLeuHisHisArgTrpThrMetSerLeuLeuGluGluPhePheArg385390395400GlnGlyAspArgGluAlaGluLeuGlyLeuProPheSerProLeuCys405410415AspArgLysSerThrMetValAlaGlnSerGlnValGlyPheIleAsp420425430PheIleValGluProThrPheThrValLeuThrAspMetThrGluLys435440445IleValSerProLeuIleAspGluThrSerGlnThrGlyGlyThrGly450455460GlnArgArgSerSerLeuAsnSerIleSerSerSerAspAlaLysArg465470475480SerGlyValLysThrSerGlySerGluGlySerAlaProIleAsnAsn485490495SerValIleSerValAspTyrLysSerPheLysAlaThrTrpThrGlu500505510ValValHisIleAsnArgGluArgTrpArgAlaLysValProLysGlu515520525GluLysAlaLysLysGluAlaGluGluLysAlaArgLeuAlaAlaGlu530535540GluGlnGlnLysGluMetGluAlaLysSerGlnAlaGluGluGlyAla545550555560SerGlyLysAlaGluLysLysThrSerGlyGluThrLysAsnGlnVal565570575AsnGlyThrArgAlaAsnLysSerAspAsnProArgGlyLysAsnSer580585590LysAlaGluLysSerSerGlyGluGlnGlnGlnAsnGlyAspPheLys595600605AspGlyLysAsnLysThrAspLysLysAspHisSerAsnIleGlyAsn610615620AspSerLysLysThrAspAspSerGlnGlu625630(2) INFORMATION FOR SEQ ID NO:52:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 2077 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: cDNA(ix) FEATURE:(A) NAME/KEY: CDS(B) LOCATION: 2..1693(xi) SEQUENCE DESCRIPTION: SEQ ID NO:52:ACGGACATCAAACATGGTTGGACTGAGCTATCCACCAGCTGTTATT46ArgThrSerAsnMetValGlyLeuSerTyrProProAlaValIle151015GAGGCATTAAAGGATGTGGACAAGTGGTCCTTTGACGTCTTTTCCCTC94GluAlaLeuLysAspValAspLysTrpSerPheAspValPheSerLeu202530AATGAGGCCAGTGGGGATCATGCACTGAAATTTATTTTCTATGAACTA142AsnGluAlaSerGlyAspHisAlaLeuLysPheIlePheTyrGluLeu354045CTCACACGTTATGATCTGATCAGCCGTTTCAAGATCCCCATTTCTGCA190LeuThrArgTyrAspLeuIleSerArgPheLysIleProIleSerAla505560CTTGTCTCATTTGTGGAGGCCCTGGAAGTGGGATACAGCAAGCACAAA238LeuValSerPheValGluAlaLeuGluValGlyTyrSerLysHisLys657075AATCCTTACCATAACTTAATGCACGCTGCCGATGTTACACAGACAGTG286AsnProTyrHisAsnLeuMetHisAlaAlaAspValThrGlnThrVal80859095CATTACCTCCTCTATAAGACAGGAGTGGCGAACTGGCTGACGGAGCTG334HisTyrLeuLeuTyrLysThrGlyValAlaAsnTrpLeuThrGluLeu100105110GAGATCTTTGCTATAATCTTCTCAGCTGCCATCCATGACTACGAGCAT382GluIlePheAlaIleIlePheSerAlaAlaIleHisAspTyrGluHis115120125ACCGGAACCACCAACAATTTCCACATTCAGACTCGGTCTGATCCAGCT430ThrGlyThrThrAsnAsnPheHisIleGlnThrArgSerAspProAla130135140ATTCTGTATAATGACAGATCTGTACTGGAGAATCACCATTTAAGTGCA478IleLeuTyrAsnAspArgSerValLeuGluAsnHisHisLeuSerAla145150155GCTTATCGCCTTCTGCAAGATGACGAGGAAATGAATATTTTGATTAAC526AlaTyrArgLeuLeuGlnAspAspGluGluMetAsnIleLeuIleAsn160165170175CTCTCAAAGGATGACTGGAGGGAGTTTCGAACCTTGGTAATTGAAATG574LeuSerLysAspAspTrpArgGluPheArgThrLeuValIleGluMet180185190GTGATGGCCACAGATATGTCTTGTCACTTCCAACAAATCAAAGCAATG622ValMetAlaThrAspMetSerCysHisPheGlnGlnIleLysAlaMet195200205AAGACTGCTCTGCAGCAGCCAGAAGCCATTGAAAAGCCAAAAGCCTTA670LysThrAlaLeuGlnGlnProGluAlaIleGluLysProLysAlaLeu210215220TCCCTTATGCTGCATACAGCAGATATTAGCCATCCAGCAAAAGCATGG718SerLeuMetLeuHisThrAlaAspIleSerHisProAlaLysAlaTrp225230235GACCTCCATCATCGCTGGACAATGTCACTCCTGGAGGAGTTCTTCAGA766AspLeuHisHisArgTrpThrMetSerLeuLeuGluGluPhePheArg240245250255CAGGGTGACAGAGAAGCAGAGCTGGGGCTGCCTTTTTCTCCTCTGTGT814GlnGlyAspArgGluAlaGluLeuGlyLeuProPheSerProLeuCys260265270GACCGAAAGTCCACTATGGTTGCTCAGTCACAAGTAGGTTTCATTGAT862AspArgLysSerThrMetValAlaGlnSerGlnValGlyPheIleAsp275280285TTCATCGTGGAACCCACCTTCACTGTGCTTACGGACATGACCGAGAAG910PheIleValGluProThrPheThrValLeuThrAspMetThrGluLys290295300ATTGTGAGTCCATTAATCGATGAAACCTCTCAAACTGGTGGGACAGGA958IleValSerProLeuIleAspGluThrSerGlnThrGlyGlyThrGly305310315CAGAGGCGTTCGAGTTTGAATAGCATCAGCTCGTCAGATGCCAAGCGA1006GlnArgArgSerSerLeuAsnSerIleSerSerSerAspAlaLysArg320325330335TCAGGTGTCAAGACCTCTGGTTCAGAGGGAAGTGCCCCGATCAACAAT1054SerGlyValLysThrSerGlySerGluGlySerAlaProIleAsnAsn340345350TCTGTCATCTCCGTTGACTATAAGAGCTTTAAAGCTACTTGGACGGAA1102SerValIleSerValAspTyrLysSerPheLysAlaThrTrpThrGlu355360365GTGGTGCACATCAATCGGGAGAGATGGAGGGCCAAGGTACCCAAAGAG1150ValValHisIleAsnArgGluArgTrpArgAlaLysValProLysGlu370375380GAGAAGGCCAAGAAGGAAGCAGAGGAAAAGGCTCGCCTGGCCGCAGAG1198GluLysAlaLysLysGluAlaGluGluLysAlaArgLeuAlaAlaGlu385390395GAGCAGCAAAAGGAAATGGAAGCCAAAAGCCAGGCTGAAGAAGGCGCA1246GluGlnGlnLysGluMetGluAlaLysSerGlnAlaGluGluGlyAla400405410415TCTGGCAAAGCTGAGAAAAAGACGTCTGGAGAAACTAAGAATCAAGTC1294SerGlyLysAlaGluLysLysThrSerGlyGluThrLysAsnGlnVal420425430AATGGAACACGGGCAAACAAAAGTGACAACCCTCGTGGGAAAAATTCC1342AsnGlyThrArgAlaAsnLysSerAspAsnProArgGlyLysAsnSer435440445AAAGCTGAGAAGTCATCAGGAGAACAGCAACAGAATGGTGACTTCAAA1390LysAlaGluLysSerSerGlyGluGlnGlnGlnAsnGlyAspPheLys450455460GATGGTAAAAATAAGACAGACAAGAAGGATCACTCTAACATCGGAAAT1438AspGlyLysAsnLysThrAspLysLysAspHisSerAsnIleGlyAsn465470475GATTCAAAGAAAACAGATGGCACAAAACAGCGTTCTCACGGCTCACCA1486AspSerLysLysThrAspGlyThrLysGlnArgSerHisGlySerPro480485490495GCCCCAAGCACCAGCTCCACGTGTCGCCTTACGTTGCCAGTCATCAAG1534AlaProSerThrSerSerThrCysArgLeuThrLeuProValIleLys500505510CCTCCTTTGCGTCATTTTAAACGCCCTGCTTACGCATCTAGCTCCTAT1582ProProLeuArgHisPheLysArgProAlaTyrAlaSerSerSerTyr515520525GCACCTTCAGTCTCAAAGAAAACTGATGAGCATCCTGCAAGGTACAAG1630AlaProSerValSerLysLysThrAspGluHisProAlaArgTyrLys530535540ATGCTAGATCAGAGGATCAAAATGAAAAAGATTCAGAACATCTCACAT1678MetLeuAspGlnArgIleLysMetLysLysIleGlnAsnIleSerHis545550555AACTGGAACAGAAAATAGGCCGAGGGGAAGAAGAGAGGGAGTGAAGGAGGGTCTA1733AsnTrpAsnArgLys560CCTATCTGCTTCTCAGCACCCACTGGCCACAGCAGGACACACCTCCAAGACCCTTGGAGG1793CTGTTGGAGCAGGTACTATCCTGGTTGACTCCACCAAGGTGAAATGAAAGTTGTATGTGA1853TTTTCCTCTTTGTTGTTCTTGTATAGACTTTTCAATTGCTGTATGTGGGATCAGCCCAGA1913CGCCAGCAACAAACTAGCAAGAGGGGTGTTTTTATGGTATAAGTCTCTAAAAGTCTAAAT1973TGGACCAAAATTAAAATGACACAAACTTAAAAAAAAATAAAATTCCTCTCATTGCCACTT2033TTTTCAATCTCTAAAAGTTACTTGCCCCCAAAAGAATATTGGTC2077(2) INFORMATION FOR SEQ ID NO:53:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 564 amino acids(B) TYPE: amino acid(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO:53:ArgThrSerAsnMetValGlyLeuSerTyrProProAlaValIleGlu151015AlaLeuLysAspValAspLysTrpSerPheAspValPheSerLeuAsn202530GluAlaSerGlyAspHisAlaLeuLysPheIlePheTyrGluLeuLeu354045ThrArgTyrAspLeuIleSerArgPheLysIleProIleSerAlaLeu505560ValSerPheValGluAlaLeuGluValGlyTyrSerLysHisLysAsn65707580ProTyrHisAsnLeuMetHisAlaAlaAspValThrGlnThrValHis859095TyrLeuLeuTyrLysThrGlyValAlaAsnTrpLeuThrGluLeuGlu100105110IlePheAlaIleIlePheSerAlaAlaIleHisAspTyrGluHisThr115120125GlyThrThrAsnAsnPheHisIleGlnThrArgSerAspProAlaIle130135140LeuTyrAsnAspArgSerValLeuGluAsnHisHisLeuSerAlaAla145150155160TyrArgLeuLeuGlnAspAspGluGluMetAsnIleLeuIleAsnLeu165170175SerLysAspAspTrpArgGluPheArgThrLeuValIleGluMetVal180185190MetAlaThrAspMetSerCysHisPheGlnGlnIleLysAlaMetLys195200205ThrAlaLeuGlnGlnProGluAlaIleGluLysProLysAlaLeuSer210215220LeuMetLeuHisThrAlaAspIleSerHisProAlaLysAlaTrpAsp225230235240LeuHisHisArgTrpThrMetSerLeuLeuGluGluPhePheArgGln245250255GlyAspArgGluAlaGluLeuGlyLeuProPheSerProLeuCysAsp260265270ArgLysSerThrMetValAlaGlnSerGlnValGlyPheIleAspPhe275280285IleValGluProThrPheThrValLeuThrAspMetThrGluLysIle290295300ValSerProLeuIleAspGluThrSerGlnThrGlyGlyThrGlyGln305310315320ArgArgSerSerLeuAsnSerIleSerSerSerAspAlaLysArgSer325330335GlyValLysThrSerGlySerGluGlySerAlaProIleAsnAsnSer340345350ValIleSerValAspTyrLysSerPheLysAlaThrTrpThrGluVal355360365ValHisIleAsnArgGluArgTrpArgAlaLysValProLysGluGlu370375380LysAlaLysLysGluAlaGluGluLysAlaArgLeuAlaAlaGluGlu385390395400GlnGlnLysGluMetGluAlaLysSerGlnAlaGluGluGlyAlaSer405410415GlyLysAlaGluLysLysThrSerGlyGluThrLysAsnGlnValAsn420425430GlyThrArgAlaAsnLysSerAspAsnProArgGlyLysAsnSerLys435440445AlaGluLysSerSerGlyGluGlnGlnGlnAsnGlyAspPheLysAsp450455460GlyLysAsnLysThrAspLysLysAspHisSerAsnIleGlyAsnAsp465470475480SerLysLysThrAspGlyThrLysGlnArgSerHisGlySerProAla485490495ProSerThrSerSerThrCysArgLeuThrLeuProValIleLysPro500505510ProLeuArgHisPheLysArgProAlaTyrAlaSerSerSerTyrAla515520525ProSerValSerLysLysThrAspGluHisProAlaArgTyrLysMet530535540LeuAspGlnArgIleLysMetLysLysIleGlnAsnIleSerHisAsn545550555560TrpAsnArgLys(2) INFORMATION FOR SEQ ID NO:54:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 29 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:54:TACGAAGCTTTGATGGGGTCTACTGCTAC29(2) INFORMATION FOR SEQ ID NO:55:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 31 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:55:TACGAAGCTTTGATGGTTGGCTTGGCATATC31(2) INFORMATION FOR SEQ ID NO:56:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 16 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:56:ATTACCCCTCATAAAG16(2) INFORMATION FOR SEQ ID NO:57:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 29 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:57:TACGAAGCTTTGATGCGCCGACAGCCTGC29(2) INFORMATION FOR SEQ ID NO:58:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 21 base pairs(B) TYPE: nucleic acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:58:GGTCTCCTGTTGCAGATATTG21__________________________________________________________________________ | The present invention relates to novel purified and isolated nucleotide sequences encoding mammalian Ca 2+ /calmodulin stimulated phosphodiesterases (CaM-PDEs) and cyclic-GMP-stimulated phosphodiesterases (cGS-PDEs). Also provided are the corresponding recombinant expression products of said nucleotide sequences, immunological reagents specifically reactive therewith, and procedures for identifying compounds which modulate the enzymatic activity of such expression products. | 2 |
This disclosure is based upon, and claims priority from, Swiss patent application No. 2029/96, filed Aug. 20, 1996, the contents of which are incorporated herein by reference.
This application claims priority under 35 U.S.C. §§119 and/or 365 to 2029/96 filed in Switzerland on Aug. 20, 1996; the entire content of which is hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to a method and a device for detecting defects in textile webs.
BACKGROUND OF THE INVENTION
Proposals for detecting defects in textile webs are described in the Textile Research Journal 63(4), pages 244-246 (1993) and 66(7), pages 474-482 (1996) under the titles: "Assessment of Set Marks by Means of Neural Nets" and "Automatic Inspection of Fabric Defects Using an Artificial Neural Network Technique". According to these publications, neural networks can be used for the detection of defects in textiles. In the disclosed methods particular input values are first determined for the network. Such input values include, for example, the distance between threads in the fabric at a given site or the mean value of this distance over the entire fabric, the standard deviation from values for the distance, the yarn mass and intensity values, which are derived from a fabric image subjected to Fourier transformation. These are all measurement values which must first be obtained from values derived from the fabric by way of more or less extensive calculations.
A disadvantage of methods of this type resides in the fact that they are not very flexible, so that the detection of defects in different fabrics requires calculations which need to be carried out in advance. Thus, it is not possible to derive or deduce input values from the web for a defect detection system which are adequate for all possible types of web texture. If an approximation of this method is nevertheless to be achieved, then a very large number of different measurement values must be determined, resulting in a correspondingly high calculation outlay. High speed and high cost computers are required to this end.
A method for detecting errors in lace is disclosed in Sanby et al, "The Automated Inspection of Lace Using Machine Vision," Mechatronics, Vol. 5, No. 2/03, Mar. 1, 1995. In this method, values for the intensity or brightness of scanning points of a picture of the original lace are compared to those of an error-free or reference picture. Values of the differences are calculated and fed to a threshold stage. Scanning points of the picture showing greatly differing values trigger an output signal. Such trigger signals are especially generated in the region of errors in the lace. Due to geometric distortion of the pictures, many apparent (but not real) errors will be detected or signaled. Therefore, a neural network is used for discriminating apparent errors from real errors. Scanning points belonging to a small area surrounding one trigger pixel are fed to the neural network, which acts as a classifier. The network is also fed with pixels and corresponding brightness values from the original picture and from the reference picture. From these three sets of pixels, the network determines if the trigger pixel is really indicating an error or not.
One drawback of this method resides in the fact that first a preliminary discrimination of errors in the lace is performed by comparing brightness values of pixels alone. Subsequently, the neural network confirms the preliminary discrimination. For that task, three sets of data must be fed to the network in order to obtain a definitive judgment. This method is not suited for inspecting textiles such as woven fabric or other types of cloth which do not show a periodically repeating structure in an image. Compared to lace, such textiles have textures wherein errors are only distinguished by modifications of the texture. Methods using differences in images do not give acceptable results. A subsequent classification in neural networks is not useful in this context.
The present invention attains the object of providing a method and a device which can be rapidly adapted to widely varying textile webs and is simple to operate.
This objective is attained by way of the skillful use of modern, cost-effective computers operating in parallel. The web is scanned in known manner, for example line-by-line, by a camera which supplies data to a memory. Values for the brightness or intensity of scanning points or partial areas of a web are stored in the memory. In this manner, the memory eventually contains an image of a section of the web. Values from connected areas are then retrieved in parallel from the memory and supplied in parallel to a neural network, which is trained to recognize defects. The neural network indicates whether there is a defect in the examined area. This result is read into a further memory, which stores this result, taking into account the position of the area on the web. As the examined areas gradually cover the entire width of the web and therefore also cover the web over a section of its longitudinal direction, conclusive data regarding defects in the examined section is eventually available.
In accordance with the invention, a neural network of a type that is known per se is used as a non-linear filter and operates directly with brightness values from a relatively large environment (e.g. 10×100 pixels) as input values for the neural network, without the need for additional measurement values. The environment is displaced pixel-by-pixel over the surface of the web, so that a filtering operation is carried out. At the output of the neural network a filtered image of the examined area is produced, in which the novel structure of the fabric is attenuated and errors are clearly identified. By means of a learning process, both the filter structure and the filter parameters are automatically determined and in this manner adapted to any type of textured and small-patterned surfaces. The learning process can be effected by the presentation of approximately 20 to 100 image patterns which contain defects, and the same number of image patterns containing no defects. By dividing the filter into two neural networks for input environments which are oriented in the warp or weft direction in the case of wovens, the distinction between warp and weft defects can be further supported.
The advantages attained by this invention can be seen in particular in that a device of this type can be constructed from cost-effective, simple computers which operate in parallel and are optimized for neural networks. As a result of the parallel processing of all input values, very high computing capacities (e.g. several Giga MAC (multiply accumulate calculations)) are attained, so that the result of the examination can also be continuously determined even at high product web velocities. Computers of this type can be extensively integrated in a single silicon chip and used in the form of add-on boards in personal computers. Examples of circuit boards of this type would be the PALM PC board made by the company Neuroptic Technologies, Inc and the CNAPS PC board made by the company Adaptive Solutions. In this manner, high inspection speeds of, for example, 120 m/min are possible.
The learning process can be effected very simply with the aid of a web section recognized as defect-free by the eye and defective sections of the web. In addition, the sensitivity of the defect detection can be increased by the particular form and orientation of the areas from which input values are derived. Using a simple learning process, a high degree of adaptability to differently textured webs is possible. No specially trained personnel are required for the simple operating procedure. The invention can be used for textured and patterned surfaces.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be explained in further detail hereinafter by way of an example with reference to the attached drawings, in which:
FIG. 1 shows part of a textile web on which different features are schematically indicated,
FIG. 2 is a schematic illustration of a non-linear filter operation,
FIG. 3 is an image of portions of a web with defect markings,
FIG. 4 is a schematic illustration of a device according to the invention,
FIG. 5 is a schematic illustration of part of the device, and
FIGS. 6a and 6b are input and output images, respectively, pertaining to a web having a defect.
DETAILED DESCRIPTION
FIG. 1 shows part of a web 1, in this case a woven fabric, for example, which is formed of warp threads 2 and weft threads 3, of which only a few are illustrated. In addition, a plurality of lines 4 are shown, as can be covered for example by a line camera, which scans the web 1 in such a manner that the entire web is covered. Lines 4 of this type can also overlap so that no gaps are left between the lines. In addition, areas 5 and 6 can be seen, which are formed by 72 partial areas 7 and 56 partial areas 8, respectively. Areas 5, 6 of this type are only defined for a given period of time and are therefore defined for other periods of time in the same form and size, but in different positions. 5a, 5b and 6a, 6b indicate such further areas in other positions, with a plurality of areas 5, 5a, 5b and 6, 6a, 6b being defined for successive overlapping intervals. These areas preferably extend with time in the direction of an arrow 9 over the width of the web 1 in such a manner that successive areas 5, 5a, 5b and 6, 6a, 6b are offset relative to one another by one partial area 7, 8.
FIG. 2 figuratively illustrates the contents of a memory in a plane 13, with input values 14a, 14b, 14c, etc., which represent the brightness or a grayscale value of the web as detected by a sensor or a camera. In a plane 15, signals are illustrated as output values or results, only one signal 16 being visible in this case, which indicates the probability that a defect is present in a corresponding area of the web. Arranged between the planes 13 and 15 is a non-linear filter operation, when this drawing is viewed in terms of function. However, the drawing can also be viewed as showing the structure of a device. In this case, 17 designates an intermediate computer and 16 an output computer. The input values 14 can also be seen as input neurons, the intermediate computers 17 as hidden neurons and the output computers 16 as output neurons of a neural network.
FIG. 3 is an enlarged view of an output image 10 of a section of the web 1. Two regions 11 and 12 containing defects are marked on the image 10 by means of darker grayscale values. These regions 11, 12 are composed of partial areas according to FIG. 1, so that, as shown in the drawing, a plurality of partial areas are occupied by a defect signal and together produce the regions 11 and 12.
FIG. 4 is a schematic illustration of the configuration of a device according to the invention. The latter comprises a camera 21 arranged directly adjacent the web 20, e.g. a CCD camera or more generally a photoelectric converter, which is connected to a memory 22. Signals from a plurality of adjacent lines 4 are stored in the memory 22 for a given period of time. These signals and lines are stored in the memory 22 according to the FIFO principle. The memory 22 is connected to a non-linear filter 23, which can be constructed for example as a computer, in which a corresponding filter program is loaded. The filter program is designed according to the principles of a neural network. The latter is connected to a memory 24, in which defect signals (or no-defect signals) are stored with their allocation to areas on the web. Also in this case, the defect signals remain stored in the memory 24 for a given period of time and the defect signals are also processed according to the FIFO principle. The memory 24 is connected via a connection 25 to a distance recorder or length encoder 26, so that data relating to the instantaneous position of the camera 21 along the web 20 can be fed into the memory 24. In order to display the results of the examinations of the textile web 20, a display unit 27 is connected to the memory 24, which can be constructed for example as a printer or monitor. However, a processing unit, e.g. a computer, can also be provided in place of the display unit 27, which processing unit subjects the content of the memory 24 to a further classification, namely so that defect regions such as the regions 11 and 12 from FIG. 3 can be compared with given criteria, so that they can be associated with different types of defects. For example, in the case of wovens, the defects can be classified into weft and warp defects. The region 11 in FIG. 3 would therefore indicate a weft defect and the region 12 a warp defect.
FIG. 5 shows a section of a non-linear filter 23 (FIG. 4), the filter being constructed in this case as a neural network. It comprises processors 30 arranged in a first layer and processors 35 arranged in a second layer. In relation to FIG. 2, the processors 30 can be regarded as exemplary embodiments for the intermediate computers 17 and the processors 35 for the output computers or output neurons 16. The processors 30 are constructed from a plurality of multipliers 31 with associated memories 32, which are all connected to an adder 33. This is in turn connected at its output to a processing stage 34, which has a nonlinear characteristic curve. The multipliers 31 are connected to the memory 22 for receiving input values 14a, 14b, 14c, etc. The processors 35 are constructed in like manner, although the processing stages 34 of the processors 30 are connected to the multipliers 31 of the processors 35. The latter comprise an output 16 for output values. The illustrated arrangement, in which the processors 30 of the first layer are acted upon by all input values of an area, is realized in this case as a parallel computer, which comprises a number of the same types of processors 30, 35.
The method of operation of the method and device according to the invention is as follows: In relation to the web 1, areas 5, 6 are first defined in the memory 22 by means of instructions that are preset in the memory or in the filter 23 connected thereto, which determine from which memory locations in the memory 22 values are taken and supplied as input values for the filter 23. On the one hand, such areas 5, 6 should have sides lying parallel to the lines 4 recorded by the camera 21 from the web 1. On the other hand, the areas should preferably also have a main direction which lies parallel to the texture features of the web 1. In this case, the area 5 lies with its main direction parallel to the weft threads 3 and the area 6 parallel to the warp threads 2.
A learning phase then follows in order to adjust the filter coefficients or filter parameters, in a known manner associated with neural networks. In this phase, the camera 21 is aimed alternately at areas containing no defects and areas containing a defect. The result which should be displayed by the filter 23 is predetermined in each case. For instance, if no defects are present, the output nodes 16 of the filter could all produce a binary zero value, whereas if a defect is present the nodes which correspond to that area of the web could generate a binary one value. In the learning phase, the computer, which acts as the filter, is operated in a mode in which it does not transmit results but adapts its coefficients and parameters from the desired results and the input values. The coefficients and parameters are first predetermined as output values, for example as values in the memories 32 or as parameters of the non-linear characteristic curve of the processing stage 34, and are adapted by the learning process according to given techniques for training a neural network, so that the filter receives a specific transmission function. For instance, the training of the neural network can be carried out using the known techniques of error back propagation and simulated annealing. A description of these techniques can be found in Hertz et al, "Introduction to the Theory of Neural Computation", Santa Fe Institute Studies in the Sciences of Complexity, Lecture Notes, vol. 1, Addison-Wesley, 1991. This training process is preferably repeated each time a new web 1, 20 is presented.
Once the learning phase is complete, the mode in the computer is changed and the detection of the defects can be carried out on a web 1 which is moved in a direction perpendicular to the arrow 9. This means that the camera now passes over the web 1 in a manner known per se, and therefore not illustrated in further detail, in the direction of the arrow 9, and thereby optically scans lines 4. The recorded values for the brightness or color intensity are supplied to the memory 22, which also stores these values in lines, for example. The values for all partial areas 7, 8 from areas 5, 5a, 5b, 6, 6a, 6b etc. are supplied in parallel from the memory 22 to the filter 23, which for each area 5, 5a, 5b, 6, 6a, 6b transmits an output value, result or signal 16. This signal indicates the probability that a defect is present in the corresponding area of the web. For instance, the probabilities might be expressed as a decimal value in the range 0.0-1.0. Referring to FIG. 3, the probabilities are shown as multi-level grayscale values, where a low probability corresponds to a lighter area and a high probability is shown as a dark area. Intermediate probabilities have corresponding grayscale values. This signal is read into the memory 24 together with data relating to the position of the area from which the signal is derived, and is stored for a period of time required by the camera 21 in order to cover a plurality of lines 4. Thus, the signals are stored in the memory 24 in storage locations associated with relative positions on the web, so as to correspond to an image 10 as shown in FIG. 3. Within this image 10 signals 16 are recognizable, which, since they are usually not isolated but occur in groups, are combined to form regions 11, 12 indicating a defect in the web 1. This image 10 can also be made visible on a display unit 27.
FIGS. 6a and 6b illustrate, respectively, an input image of a larger portion of a web having a horizontal stripe defect and the corresponding grayscale output image which is produced. As can be seen, the defect is readily identifiable from a simple comparison of brightness values in the output image.
If a processing unit is provided instead of the display unit 27, the processing unit is constructed as a computer which can carry out an image segmentation in order to combine individual pixels to form regions according to a suitable method, as described for example in "Rafael C. Gonzalez and Paul Wintz: Digital Image Processing, Addison-Wesley Publishing Company, Reading Mass. 1987".
If the non-linear filter 23 has a construction according to FIG. 5, then input values 14a, 14b, 14c, etc., selected according to the areas 5, 6 are all supplied to each of the processors 30 of the first layer. Each processor 30 therefore comprises the same number of multipliers as the number of partial areas in the sensed area. In the multipliers, the input values 14 are multiplied by factors which are stored in the memories 32 and then added in the adder, so that a mixed value is produced, which is composed of all input values of an area. This mixed value is further changed by the non-linear characteristic curve of the processing stage 34. The adapted mixed values are in turn supplied to the processors 35 of the second layer, where they are processed in the same manner as in the processors 30. An output value for each area is produced at the output 16. These output values are supplied to the memory 24 where they are distributed as illustrated in FIG. 3.
Although the invention is explained herein by way of example of a woven fabric, it is equally possible to use the invention with knitted or similarly textured webs. In that case, particular attention should be paid to ensure that the areas 5 and 6 are aligned so that their main axes lie parallel to prominent lines in the pattern or knitting. In this respect, it is also possible to arrange the main axes of the areas 5, 6 in any manner (not at right angles) and to select a direction for the progression or displacement of the areas other than that according to the arrow 9. | The invention relates to a method and a device for detecting defects in textile webs. In order to rapidly adapt devices of this type to widely varying textile webs and to be able to operate such devices simply, brightness values are determined from the web and are supplied directly to a filter constructed as a neural network. The output results of the neural network can be displayed as grayscale values to indicate detected defects. | 3 |
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/204,128, filed Aug. 14, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to glass laminates. The present invention particularly relates to laminates of glass and polyvinylbutyral, and a process of preparing same.
[0004] 2. Description of Related Art
[0005] Glass laminates that include plasticized polyvinyl butyral (PVB) interlayers can be used in various applications, including use in automotive safety glass applications such as windshields and side glass; in architectural applications such as windows, doors and/or building panels; and in various other applications such as in display cases, as shelving, and the like.
[0006] Glass/PVB laminates can be prepared by conventional methods. Typically, a laminate can be prepared by first positioning a sheet of PVB between two pieces of glass to obtain an assembly, and trimming the excess PVB interlayer. A “pre-press” is obtained from the assembly by removing air trapped between the glass and the interlayer, and then sealing the edges. A conventional method for edge sealing requires placing the assembly inside of a rubber bag and removing the air from the bag by applying vacuum. The rubber bag and contents can then be passed through a furnace wherein the temperature is increased to about 135° C. in order to obtain the pre-press. A pre-press so obtained can be heated in an autoclave wherein heat and pressure are applied, residual air is dissolved in the PVB interlayer, and bonding occurs between the interlayer and the surface being laminated.
[0007] An interlayer having a smooth surface can present problems during the assembly and de-airing steps of a lamination process if a vacuum bag system is used to make the pre-press. In the assembly step, the smooth pattern allows the interlayer to tack too easily to the glass, making placement of the interlayer difficult. In the de-airing step, a smooth pattern can lead to a laminate having trapped air, and flaws in the laminate can result therefrom. It is known that interlayers having a rough surface can facilitate de-airing. Rough surface patterns can be generated by conventional methods, including use of an embossing tool to impart a reproducible pattern on the surface of the interlayer material. It is also conventional to generate a randomly irregular surface pattern by a melt-fracture process, which can provide channels by which air can escape during the lamination process.
[0008] In a typical windshield laminating process, the PVB interlayer is first subjected to a shaping step wherein the PVB interlayer is differentially stretched such that the shaped interlayer better conforms to the curvature of the vehicle for which the windshield is designed. In the shaping step, the PVB roll is unwound, and the interlayer is heated to approximately 100° C. and then passed over one or more cones which are smooth, and then chilled to approximately 10° C. for storage, and then cut into blanks slightly larger than the size of the windshield. Stresses incurred in the shaping process are partially relaxed as the blanks are conditioned at 10° C. During the shaping step, some of the pattern roughness is pressed out temporarily, but will recover according to stress relaxation kinetics well known in the art of polymer rheology.
[0009] For interlayers with surface patterns generated in a melt-fracture process, haze in a pre-press can be a problem, especially if the interlayer material is used within twelve hours of being shaped for lamination in a vacuum bag pre-pressing system. Pre-presses with less than 15% light transmission are typically rejected. Use of an embossing tool can be effective in resolving the de-airing and pre-press clarity concerns, but is more costly and more work intensive than use of a melt fracture process. An embossing process is inflexible relative to the melt fracture process, with respect to producing different patterns on the same equipment.
[0010] While use of rough patterns obtained by a melt-fracture process could improve the effectiveness of de-airing by vacuum, rough patterns generated by melt fracture require more energy to melt down in the heating step. This could render the pre-press hazier than if it had been made from a smoother interlayer. In a conventional process for making flat laminates, a glass/PVB/glass assembly is typically heated to the point where the PVB attains a temperature of abut 50-90° C. At this temperature, the entire assembly is passed through a set of nip rolls, and the nip rolls exert pressure that squeezes out the interstitial air and also seals the edges of the pre-press. Pre-presses that use conventional PVB with a roughened surface obtained by a melt fracture process tend to be hazy if R z is above 30 micrometers.
[0011] It is desirable to obtain an interlayer material with a surface rough enough to minimize haze in a pre-press, yet maintain a desirable balance of physical properties of the interlayer, without requiring the capital investment, loss of yield, loss of flexibility, or possible contamination that can result from use of an embossing tool. Therefore it can be desirable to obtain such a rough surface without use of an embossing tool.
SUMMARY OF THE INVENTION
[0012] In one aspect, the present invention is a plasticized polyvinyl butyral sheet having a directional surface pattern created using a melt fracture process during extrusion of the sheet.
[0013] In another aspect, the present invention is a plasticized polyvinyl butyral sheet having a washboard surface pattern created using a melt fracture process during extrusion of the sheet.
[0014] In another aspect, the present invention is a plasticized polyvinyl butyral sheet having a herringbone surface pattern created using a melt fracture process during extrusion of the sheet.
[0015] In another aspect, the present invention is a process for creating a directional pattern on a surface of a plasticized polyvinyl butyral sheet using a melt fracture process during extrusion of the sheet.
[0016] In still another aspect, the present invention is a laminate comprising a plasticized polyvinyl butyral interlayer, wherein the interlayer is obtained from a polyvinyl butyral sheet having a directional surface pattern created using a melt fracture process during extrusion of the sheet.
DETAILED DESCRIPTION
[0017] In one embodiment, the present invention is a plasticized polyvinyl butyral (PVB) sheet having a roughened surface wherein the surface has directionality imparted by a melt fracture extrusion process. PVB sheeting of the present invention is plasticized. Conventional plasticizers known in the art of preparing PVB sheets can be used in the practice of the present invention. Such plasticizers include, but are not limited to: triethylene glycol-di-2-ethyl butyrate; triethylene glycol-di-2-ethyl hexanoate; and dibutyl sebacate.
[0018] The roughness of the surface of a PVB sheet of the present invention is such that haze in a glass/PVB pre-press is low even if the PVB is used within 12 hours after it is stretched. Surface roughness can be measured by conventional methods, and can be expressed by the term R z . In a washboard PVB sheet of the present invention R z is greater than about 30 micrometers, as determined by ISO R468. Preferably a washboard pattern of the present invention has a roughness of greater than about 35, more preferably greater than about 40 and most preferably from about 35 to about 100. In a herringbone pattern of the present invention, the R z is less than about 35, preferably less than about 30, more preferably from about 15 to about 35, and most preferably from about 20 to about 30 micrometers. In a PVB sheet of the present invention, the rough surface has a directional pattern, and the rough directional pattern is obtained without use of an embossing tool.
[0019] In another embodiment, the present invention is a laminate comprising at least one layer of PVB and at least one layer of glass, wherein the PVB layer is obtained by an extrusion process wherein a roughened PVB surface having directionality is obtained without use of an embossing tool. The laminate is prepared according to conventional methods, wherein an assembly comprising at least one layer of PVB of the present invention is heated, and then de-aired under vacuum and at elevated temperature to form a pre-press. Alternatively, the laminate can be prepared by heating the assembly in an oven and then passing it through one or more pairs of nip rolls. The pre-press can be autoclaved according to conventional methods and conditions to yield a finished laminate article.
[0020] In still another embodiment, the present invention is a process for preparing a PVB sheet having a roughened surface having directionality imparted using a melt fracture extrusion process, without the aid of an embossing tool. Directionality, as the term is used herein, refers to the tendency of a roughened pattern of the present invention to have an ordered, repetitive pattern that gives the appearance of an embossed pattern. However, such a pattern is obtained without using an embossing tool. As such, problems associated with use of an embossing tool are eliminated. Problems associated with use of an embossing tool include, for example, surface defects and material loss caused by adhesion of the sheet material to the tool. A directional surface pattern of the present invention provides ordered channels that are formed by a continuous alignment of the troughs of roughened surface to provide substantially uninterrupted channels for airflow. Uninterrupted channels in a surface pattern can provide the benefit of more efficient “de-airing” in a lamination process than a surface pattern having a random array of peaks and valleys. An extruded sheet of the present invention, viewed on a 3-dimensional axis wherein the height and depth of the surface pattern is shown on the y-axis, the sheet length as it is extruded from the extruder is shown on the x-axis, and the depth of the sheet in the cross-web direction is represented on the z-axis, has channels that run in the cross-web direction and that are substantially uninterrupted by the random occurrence of a raised portion of the surface blocking the channel. The present invention provides a process for obtaining a non-random pattern having substantially uninterrupted channels in the cross-web direction without use of an embossing tool.
[0021] The process comprises varying certain conditions and parameters in the extrusion process of PVB sheeting material. To prepare conventional PVB sheeting material, typically parameters can be varied to control surface pattern. Some parameters that can be varied are die body temperature and die gap, sheet caliper, lip stream pressure, lip gap, air gap, content of plasticizer, temperature of polymer, throughput of molten polymer per unit die width, and temperature of quench water. Other parameters can be varied as well. The directional patterns of the present invention can be obtained in the process of the present invention by varying the die pressure.
[0022] Under certain die pressure operating conditions, a washboard pattern is one type of directional pattern that can be obtained on the PVB surface. By “washboard pattern” it is meant a regular pattern having substantially uninterrupted channels wherein the troughs, or surface depressions, of an extruded sheet are aligned in the cross-web direction to form substantially straight lines. The lines can run parallel to the front edge of the extruded sheet, or can be at an angle of from about 1° to about 45°. For example, a washboard pattern can be obtained by operating at a die pressure of greater than 58 kg/cm 2 (5.69 MPa). A washboard pattern or surface, as the term is used herein, describes a surface having alternately high (1) and low (2) areas of elevation that form ridges (3), similar to the surface of a washboard. The ridges on a PVB surface of the present invention can be nearly parallel to the cross-web direction of the sheeting as it is extruded, the cross-web direction being the direction perpendicular to that of the extrusion. Under certain other conditions of die pressure, a herringbone pattern can be obtained on the PVB surface. A herringbone pattern is a second type of directional surface pattern that can be obtained in the process of the present invention by varying process conditions. By “herringbone pattern” it is meant a regular pattern having substantially uninterrupted channels wherein the troughs, or surface depressions, of an extruded sheet are aligned in the cross-web direction to form channels that appear to regularly change direction up and down in an alternating pattern, passing through a mid-line, and creating the appearance of “zig-zag” channels. For example, a herringbone pattern can be obtained by varying die pressure such that the pressure is below 37 kg/cm 2 (3.63 MPa). The herringbone and washboard patterns are shown in FIG. 1 and FIG. 2 , respectively. Other patterns can be obtained by varying process conditions, but the directional patterns of the present invention are controlled primarily by the die pressure.
[0023] Throughput (rate of polymer through the die) can be in the range of from about 600 to about 1000 kg per hr per meter, depending on the equipment being used.
EXAMPLES
[0024] The Examples and comparative examples herein are included for illustrative purposes only, and are not intended to limit the scope of the present invention.
[0025] In Examples 1-25, 100 parts of dry PVB flake of nominally 18-23% by weight of un-butyralated vinyl alcohol groups were mixed with 35-40 parts of tetraethylene glycol di-n-heptanoate plasticizer and one or more light stabilizers marketed under the tradename “Tinuvin” by Ciba-Geigy Co. and an antioxidant which were pre-mixed in the plasticizer continuously in a twin-screw extruder. The melt was forced through a slot die and formed a sheeting of 0.76 mm nominal thickness. In addition, agents for modifying surface energy of the bulk interlayer and usual adjuvants such as antioxidants, colorants and ultraviolet absorbers which do not adversely affect the functioning of the surface energy modifying agent and adhesion control agent can be included in the PVB composition. The melt at the die is at approximately 200-220° C. The lips of the die are heated by injecting pressurized steam into cavities therein. The lip temperature is controlled by the pressure of the steam injected. One of the die lips is adjustable so that as it opens, the back-pressure in the die is decreased and vice versa. The position of this lip is computer-controlled, and a desired back-pressure in the die (die pressure) is used as input.
[0026] PVB sheeting having washboard or herringbone pattern was prepared on conventional extrusion equipment by varying the condition of die pressure. The same equipment was used for all of the examples. The conditions and results are given in the Table below.
TABLE Washboard (W) or Lip Steam Ex. Herringbone (H) or Die Pressure Pressure R z (average) No. Random (R) (kg/cm 2 ) (kg/cm 2 ) (micrometers) 1 W 58.8 6.5 62.8 2 H 35.5 6.5 24.4 3 H 35.5 6.5 24.7 4 H 33.5 6.5 29.0 5 H 31.5 6.5 27.2 6 H 29.2 6.5 24.4 7 H 33.6 6.5 28.1 8 H 33.4 6.5 27.6 9 H 33.8 15 26.7 10 H 34.1 15 26.6 11 H 36.0 15 24.3 12 R 62.9 15 47.9 13 R 63.0 10 75.2 14 W 62.8 6.5 80.0 15 W 58.2 6.5 54.5 16 W 58.4 6.5 63.9 17 W 59.3 6.5 60.5 18 W 58.5 6.5 65.1 19 W 58.7 6.5 60.2 20 W 58.6 6.5 65.1 21 W 58.7 6.5 66.5 22 W 60.3 6.5 73.3 23 W 60.0 6.5 70.9 24 W 58.4 6.5 59.8 25 W 60.1 6.5 81.9
Comparative Example 26
[0027] Twenty full size windshields were prepared using a PVB interlayer commercially available from DuPont under the trade name Butacite® BE-1120 with a random surface pattern generated by melt fracture. The die pressure used was 62.9 kg/cm 2 (61.7 MPa), lip steam pressure was 15 kg/cm 2 (14.7 MPa). The roughness in terms of R z was 47.9 micrometers, but there was no directionality. The interlayer was shaped using typical shaping equipment, and the shaped interlayer was allowed to recover at about 15° C. for 4 hours. The pre-presses were prepared using a commercial vacuum-bag system with approximately 5 minutes of vacuum at ambient temperature, and 10 minutes inside an oven in which the PVB temperature gradually rose to about 100° C. at the end of that period. Ten of the pre-presses were very hazy, and were judged to be unusable (50% yield).
Comparative Example 27
[0028] Another twenty full size windshields were made of the same interlayer as in Comparative Example 26 except that the shaped interlayers had 8 hours of recovery after shaping. Five of the pre-presses were judged unusable (75% yield). This example shows that longer recovery time improves pre-press yield.
Example 28
[0029] Twenty windshields were prepared using the procedure in Comparative Example 26, except that the interlayer had washboard pattern, and Rz was 62.8 micrometer. It was made with die pressure of 58.8 kg/cm2 (57.7 MPa) and lip steam pressure of 6.5 kg/cm 2 (6.4 MPa). The interlayer had 4 hours of recovery time after shaping before it was assembled. One of the twenty pre-presses was judged unusable (95% yield). The pre-press yield was much higher than that in Comparative Example 26 although the sheeting was rougher, leading one skilled in the art to suspect that the pre-press would be hazier.
Example 29
[0030] Twenty windshields were prepared as in Example 28, except that the interlayer had 8 hours of recovery time after shaping before it was assembled. None of the twenty windshields was judged unusable (100% yield). | De-airing of PVB/glass laminates can be improved, while haze in the pre-press is minimized and sleep time reduced as a result using a PVB sheet having a roughened surface with directionality. A roughened surface with a washboard pattern that is useful in this regard can be obtained by varying certain conditions of a melt-fracture extrusion process. | 1 |
BACKGROUND
In the drilling of oil and gas wells it is advantageous to be able to pass large diameter drill bits and bits which are slightly oversized through the landing shoulder bore of a wellhead member. While it might be suggested that boring out the wellhead member to pass such bits would be a solution to this problem it would reduce the strength of the member and its pressure rating. Reduction of the size of the landing shoulder alone would reduce the load carrying capacity of the landing shoulder.
One attempt to increase the through bore for the passage of large diameter bits and slightly oversized bits or various downhole pieces of equipment is disclosed in U.S. Pat. No. 3,684,016. Such patent suggests a split support ring that deflects radially outward into a groove in the wellhead hanger body. However, such construction, while possibly supplying adequate support has tendencies for the split ring to catch prematurely, or not all if the recess is filled with unexpected deposits.
Another example of a string hanging system is shown in U.S. Pat. No. 4,295,665. Such system includes a locking ring 60 which is a split ring spring biased to move outward and coacts with a shear pinned lock positioning element 97 which is a split spring biased inwardly. The element 97 includes grooves on its surface 110 to restrict the development of radial forces against the interior of the casing suspension collar 22 and also outer upwardly facing teeth 114 which are recited to engage the casing to transfer a portion of the weight into the outer collar 22. Such description set forth in such patent is believed to be contradictory in that one portion (grooves on surface 110) is to restrict the development of radial forces and the other (teeth 114) is to transfer radial forces to collar 22. Further upwardly directed teeth 114 will have a minimum of load bearing capacity as compared to downwardly directed teeth usually provided in hanger slips. Difficulties can develop if the locking ring recess is blocked by deposits or if it can possibly catch on joints or other grooves in the collar.
SUMMARY
The present invention relates to an improved wellhead assembly including a wellhead member with a bore therethrough and an upwardly facing internal shoulder, a hanger within the bore of the wellhead member, a support ring surrounding said hanger and having a downwardly and inwardly facing internal taper and an external gripping surface, said support ring adapted to seat on said wellhead shoulder, said hanger having an external downwardly and inwardly directed taper coacting with said support ring internal tapered surface when the support ring is on the wellhead shoulder to force said ring outward into gripping engagement with the interior of said wellhead member above the wellhead shoulder.
An object of the present invention is to provide an improved wellhead assembly with an internal landing shoulder sufficiently small to allow an oversized drill bit to pass therethrough without reducing the load supporting capacity or pressure rating of the wellhead assembly.
Another object is to provide an improved wellhead assembly which transfers a portion of the hanger load into the wall of the wellhead member above the landing shoulder.
A further object is to provide an improved wellhead assembly which assures landing on the landing shoulder without any problem of premature catching in grooves or recesses in the stack.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the present invention are hereinafter set forth with respect to the drawings wherein:
FIG. 1 is a vertical sectional view of a wellhead assembly of the prior art.
FIG. 2 is a vertical sectional view of the improved wellhead assembly of the present invention.
FIG. 3 is an elevation view, partly in section, of the improved support ring of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Wellhead assembly 10 of the prior art as shown in FIG. 1 includes wellhead member 12 having bore 14 therethrough with landing shoulder 16 facing upwardly and inwardly and hanger 18 with support ring 20 seated on landing shoulder 16 in supporting relationship to hanger 18. Hanger 18 has downwardly facing shoulder 22 with seal ring 24 positioned between shoulder 22 and the upper end of support ring 20. Nut 26 is threaded onto the lower exterior of hanger 18. Hold down screws 28 thread through wellhead member 12 and engage with the lower portion of groove 30 in the exterior of hanger 18 to ensure that hanger 18 remains in landed position. Seal flange 32 is suitably secured to the upper end of wellhead member 12.
In such prior art structure, the diameter of wellhead member 12 below landing shoulder 16 is preselected to permit passage of the largest size of drill bit expected to be used. However, when a drill bit is slightly oversized, it will not pass through wellhead member 12. If the bore 14 is enlarged above and below shoulder 16, the pressure rating of wellhead member is reduced and if it is enlarged only below shoulder 16, the load carrying capacity of landing shoulder 16 is reduced.
The foregoing problem is solved by the improved wellhead assembly 40 shown in FIG. 2. Wellhead assembly 40 includes wellhead member 42 having bore 44 therethrough with landing shoulder 46 therein and hanger 48 which is supported within wellhead member 42 as hereinafter described. In an assembly of the same size and pressure rating, the inner diameter of member 42 below shoulder 46 is larger than the inner diameter of member 12 below shoulder 16 shown in FIG. 1. Hanger 48 includes downwardly facing shoulder 50, seal ring 52, energizing ring 54, with seal ring 52 positioned between shoulder 50 and the upper end of energizing ring 54, support ring 56 which engages landing shoulder 46 and the bore above shoulder 46 and ring 54 and retainer nut 58 threaded onto the lower exterior of hanger 48 as shown. Hold down screws 60 thread through member 42 and are adapted to engage the lower portion of groove 62 to retain hanger 48 in seated position within member 42. Seal flange 64 is suitably secured to the upper end of wellhead member 42.
Since landing shoulder 46 is smaller it will not support as much load as it would if it were larger. In order that the laod capacity of the improved wellhead assembly 40 of the present invention is not sacrificed to the larger bore 44, energizing ring 54, support ring 56, hanger 48 and the interior of wellhead member 42 coact to provide such incremental load capacity as hereinafter explained. Energizing ring 54 has an inner surface 66 which is parallel to and slightly larger than the diameter of the hanger surface around which ring 54 is positioned. The exterior of ring 54 includes upper cylindrical surface 68, lower cylindrical surface 70 and tapered surface 72 therebetween. Surface 72 tapers downwardly and inwardly at an angle substantially less than 45° and preferably between 15° to 23° and urges support ring 56 outwardly into a position for engaging member 42.
Support ring 56 has inner surface 74 which has the mating taper to surface 72 of ring 54 and ends in inner cylindrical surface 76, seating surface 78 and exterior grooved surface 80. Seating surface 78 is tapered downward and inwardly at the same angle as landing shoulder 46 for seating thereon. Grooved surface 80 is preferably serrated with "phonograph" grooves, such as a 1/32 inch pitch thread, however, such grooves may have downwardly facing teeth.
The interior surface 82 of wellhead member 42 above landing shoulder 46 is substantially the same diameter as the exterior of support ring 56 with only sufficient clearance so that expansion of support ring 56 into gripping engagement does not expand it beyond its elastic limit. For example, normally a tolerance of 0.015 inches per inch of diameter would be allowed but with the present invention a tolerance of only 0.005 inches per inch of diameter is used to ensure that ring 56 is not expanded beyond its elastic limit. Also, support ring 56 is preferably made of a 414 stainless steel. Inner surface 84 of wellhead member 42 above surface 82 is of a larger diameter so that ring 56 moves readily therethrough.
When hanger 48 has been lowered to the position shown in FIG. 2, the weight of hanger 48 and the string (not shown) which it supports is exerted by shoulder 50, through seal ring 52 to energizing ring 54. The load is transferred to support ring 56 through the tapered surfaces 72 and 74. This expands ring 56 into tight engagement with surface 82 so that a portion of the load is transferred to and carried by surface 82. The expansion of ring 56 is maintained within its elastic limit so that on relieving of the load and the upward movement of energizing ring 54 by the engagement of nut 58, ring 56 contracts to its original shape and can be moved out of wellhead member 42. Since ring 56 is not permanently deformed in expanding into supporting engagement with surface 82, it may be left on hanger 48 and reused during further running operations. | A wellhead assembly with an increased through bore for passing slightly oversized drill bits therethrough with a substantially reduced landing shoulder, and an improved landing assembly which transfers a portion of the stresses through the energizing ring and support ring into the wellhead body along the straight bore above said landing shoulder. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a pedal parking brake device which actuates a parking brake of wheels of a car or the like and performs the release thereof.
Recently, a pedal parking brake device equipped with an automatic change gear was used in place of a side brake which performs a parking brake by hand. This pedal parking brake device which is shown in FIGS. 12 to 14, when a brake pedal 10 is stepped on, a diameter of a coil spring 11 wound in closely contact state around a core bar positioned at a pivotally supporting portion of the brake pedal 10 integrated therewith is enlarged, whereby brake pedal 10 pivots together with core bar. By this, a brake cable 12 connected with brake pedal 10 is pulled thereby causing a braked state in a brake body (now shown).
When the foot is removed from the brake pedal 10 in this state, a force adapted to return the brake pedal 10 to an original positions acts by a return spring (not shown) of the brake body side. However, since this force acts in a direction to reduce the diameter of the coil spring 11 of the core bar, the rotation of the brake pedal 10 is locked to maintain a braked state. The release of the brake is performed by enlarging the diameter of the coil spring 11 by pulling a release cable 13 via a lock-removing member 14. In other words, when the diameter of the coil spring 11 of the core bar is enlarged, the brake pedal 10 returns to the original position by the action of the return spring of the brake body whereby the parking brake is released.
In this case, a hook portion 11a at one end of the coil spring 11 is latched around a pin 16 in a U-type fixed to a base 15 fixed to the car body.
However, in a conventional art, when the load of the brake increases, the hook portion 11a having a U-type design is pulled to the coil side (see two-dot chain line in FIG. 14), causing the lock to loosen. For this reason, there exists a need in the art to make a brake which can be maintained at high loads.
Further, when the brake pedal 10 is stepped on, the U-type hook portion 11a of the coil spring 11 moves so that the pin 16 slips out. So far it has not been possible to control the movement of the coil spring. Consequently, when the U-type hook portion 11a moves, the lock of the brake pedal decreases.
In other words, the prior art lacks the ability to control the play between the U-type hook portion 11a of the spring 11 and the pin 16.
The present invention is designed to overcome this prior art problem.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a pedal parking brake device which maintains a high load brake by preventing the decrease of the lock of the brake pedal.
A pedal parking brake device comprises a rotation lock including a coil spring having a hook portion at one end. The coil spring is wound in close contact state around a core bar positioned at a supporting portion of a brake pedal. One end of a hook portion of the coil spring is latched with a pin at base side and the other end is abutted against a lock releasing member. The end of hook portion of the coil spring is surrounded with a fixed member fixed to the base side.
Consequently, since the hook portion is surrounded by the fixed member fixed to the pin at the base side, the transformation and the movement of the hook portion are prevented, and the play does not occur between the hook portion and the pin. Thus, preventing a loosening of the lock of the brake pedal, and consequently, maintaining the brake of high loads.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a first embodiment of this invention.
FIGS. 2 and 3 are sectional views taken along line II--II and line III--III in FIG. 1 respectively.
FIG. 4 is a sectional view taken along line IV--IV in FIG. 3.
FIG. 5 is a sectional view correspondent to FIG. 4.
FIG. 6 is a sectional view of a second embodiment of this invention co respondent to FIG. 3.
FIG. 7 is a sectional view taken along line VII--VII in FIG. 6.
FIG. 8 is a sectional explanation view of a third embodiment of this invention.
FIG. 9 is a sectional view of the third embodiment of this invention correspondent to FIG. 6.
FIG. 10 is a sectional view of a fourth embodiment of this invention correspondent to FIG. 9.
FIG. 11 is a sectional view taken along line XI--XI of FIG. 10.
FIG. 12 is a plan view of a conventional art.
FIG. 13 a sectional view taken along line XIII--XIII in FIG. 12.
FIG. 14 is a sectional view taken along line XIV--XIV in FIG. 13.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1 to FIG. 11, where the element of the embodiment of the present invention is the same as in the prior art device, the same reference number is used.
In FIG. 1 and FIG. 2, an approximately central portion of the base 1 fixed to the car body is formed to be a cylinder having a bottom portion, an upper portion, a cylindrical portion 1a therebetween. The cylindrical portion is pivotally surrounded with brake pedal 10 made of synthetic resin. Around the outer circumference of the cylindrical portion 10a of the brake pedal 10, a cylindrical core bar 2 made of metal is provided.
At the outer circumference of the core bar 2, a coil spring 11 is provided to wind it in a contact state. The coil spring 11 is provided at one end with a hook portion 11a which is latched to a pin 3 fixed with pressure to the base 1, while the other end 11b of the coil spring 11 is abutted against one end of the lock releasing member 14. The other end of lock releasing member 14 is connected to a release cable 13, said lock releasing member 14 is provided rotatably to the bottom of the cylinder portion 1a as shown in FIG. 2.
A metallic plate 4 having a connecting hole connected with a brake cable 12 at the top end thereof is connected to the upper portion of the core bar 2 through a latching portion. The core bar 2 and the plate 4 may be inserted into the brake pedal 10.
One end of the brake cable 12 is connected to the brake pedal 10 by latching with a pin provided through a hole for connecting the plate 4 (please see FIGS. 1 and 2).
The U-type hook portion 11a of the coil spring 11 hooks around pin 3 which is inserted through base 1 and held by pressure. The U-type hook portion 11a is surrounded by a fixed member 6 which is attached to pin 3 with nut 5 as shown in FIGS. 3 and 4.
Fixed member 6 is formed having a side wall with a U-type form corresponding to the outer portion of hook portion 11a as shown in FIG. 4.
Using the above-description of the invention, when the brake pedal 10 is stepped on, it moves in a counterclockwise direction, the diameter of the coil spring 11 is enlarged (unwinding), and the core bar 2 and the plate 4 rotate with the brake pedal 10. As a result, the brake cable 12 is pulled and the brake is applied. When the foot is removed from the brake pedal 10 after applying the brake, a force returns the brake pedal 10 to an original position operates by the action of the return spring of the brake body. However, the force in this direction is one which reduces the diameter of the coil spring 11 (winding) and the rotation of the core bar 2 is locked by strongly winding the coil spring 11. When the rotation of the core bar 2 is locked, the rotation of the plate 4 is also locked and the drawn-out brake cable 12 stops at the position thereof as it is, thereby being able to maintain a brake applying state.
At the same time, when the foot is removed from the pedal 10 after stepping, a force in A direction (FIG. 1) is applied to the hook portion 11a of the coil spring 11. By this, the hook portion 11a is transformed to a form as shown in a two-dot chain line of FIG. 14 described in the prior art. However, since the hook portion 11a is enclosed by the fixed member 6 (when the form of the hook portion 11a has rather an opened form than the form of the fixed member 6, the hook portion 11a is reformed by side wall of the fixed member 6). Thus, the transformation of the hook portion 11a does not occur. Further, when the brake pedal 10 is stepped on, the hook portion 11a is apt to move in the opposite direction against A direction (a direction drawn out from pin 3), but with the present invention, the hook portion 11a does not move because it is surrounded with the fixed member 6.
Accordingly, the brake pedal is locked instantaneously and the brake operates efficiently.
The releasing of the parking brake may be performed by rotating the lock releasing member 14, pulling the release cable 13 and moving the hook portion 11b of the other end of the coil spring 11, thereby enlarging the diameter of the coil spring 11. In other words, when the diameter of the coil spring 11 is enlarged, the lock of the core bar 2 by coil spring 11 is released and the brake pedal 10 is returned to the original position by the action of the return spring of the brake body whereby the parking brake is released.
FIG. 6 and FIG. 7 illustrate another embodiment of this invention. When the hook portion 11a of the coil spring 11 is strongly bent, and there occurs a clearance between the fixed member 6 and the hook portion 11a as shown in FIG. 5, the hook portion 11a moves in C direction until the clearance disappears if a force is applied in B direction. By this, the hook portion 11a moves in B direction.
To remedy this problem, a fixed member 7 shown in FIG. 6 and FIG. 7 is formed so as to have a side wall having an approximately U-type form corresponding to outer portion of the hook portion 11a and a protruding portion 7a which pinches the released end of the hook portion 11a to the side wall, thereby removing the clearance between the fixed member 7 and the hook portion 11a. With the removal of the clearance and the stoppage of the movement of the hook portion 11a, the brake pedal 10 locks instantaneously, thereby being able to maintain the brake at a high load.
Further, when the rotation force of the core bar 2 in D direction becomes larger, the fixed member 6 rotates in E direction together with the hook portion. By this, F portion of the lock spring 11 transforms to a bending form. This transformation enlarges the play at the time of locking, which causes a breakage of the lock spring 11. This is the same with respect to the fixed member 7.
For this purpose, the movement of fixed member 7 is prevented with projection 7b attached to fixed member 7 and with a hole 1a in base 1 in which the fixed member 7 is inserted as shown in FIG. 9, as a third embodiment.
Further, as shown in FIG. 10 and FIG. 11, as a fourth embodiment, base 1 is provided with a convex step portion 1b and a U-type groove 1c formed at the convex step portion 1b. The hook portion 11a of the lock spring 11 is inserted through this U-type groove 1c. The U-type groove 1c is formed so as to correspond to the outer form of the hook portion 11a.
With this embodiment, since the hook portion 11a is enclosed with U-type groove 1c, the transformation and the movement of the hook portion 11a are eliminated.
In this embodiment, a cover member 16 clamped with a screw 15 is provided with a latching projection 16a with a half cut and a latching hole 1d provided at the concave step portion 1b of the base 1, thereby strengthening a clamp so as to stop the rotation of the cover member 16 by latching the latching projection 16a and the latching hole 1d.
In the fourth embodiment, of course the hook portion 11a of the coil spring 11 does not transform even if any force may apply to the coil spring.
As described above, according to this invention, since the hook portion does not transform, the brake does not loosen upon the return of the brake pedal. Further, since the movement of the hook portion can be prevented when brake pedal is stepped on, this also prevents the brake from loosening upon return of the brake pedal.
Furthermore, even if the form of the hook portion disperses somewhat, the movement of the hook portion can be prevented, since the dispersion is corrected by the fixed member as a fixed portion. | A pedal parking brake device comprising a rotation lock of the brake pedal including a coil spring having a hook portion. The coil spring is outwardly inserted to a core bar positioned at the rotatably supporting portion of the brake pedal in closely contact state, one end of the hook portion of the coil spring is attached to a base side, while another end abuts against a lock releasing member. | 8 |
The present invention relates to manufacture of plastic shrink wrap coverings on glass containers of the type disclosed in U.S. Pat. No. 3,760,968; and particularly of the type disclosed on FIG. 14 of said patent.
BACKGROUND OF THE INVENTION
The process of our copending application, Ser. No. 672,229 filed Mar. 31, 1976, U.S. Pat. No. 4,016,706, entitled "Method of Controlling Shrinkage of a Sleeve Wrap on a Container" provides a need for a production machine to produce the plastic encapsulated bottles provided with shrunken sleeves of heat shrinkable polyolefin type material.
SUMMARY OF THE INVENTION
In the present invention, a machine is provided for heat shrinking sleeves of plastic onto a form, such as a bottle, so as to substantially cover the exterior thereof. The invention includes a controlled rotation of the bottle and the sleeve telescopically applied thereon about the central axis of the bottle during heating such that the sleeve will shrink uniformly over the adjacent area of the bottle. The controlled bottle rotation diminishes wavy or folded tops of the sleeves being shrunken on the bottle.
The chuck on the conveyor carrying the bottle is rotatable about the common central axis of the two. As the bottle and sleeve enter the oven, the chuck is rotated such that the rotational speed of the bottle about its axis will be regulated relative to line speed, shrink temperature, shrink dimension and properties of the material. The controlled bottle rotation establishes a centrifugal force on the sleeve as the material undergoes its initial heating in the oven and the sleeve remains substantially erect and billowed while the material has time to heat further so that it progressively shrinks. The shrinkage will progress upon further heating by the sleeve first engaging the larger diameter portion of the bottle and progressively snugly shrinking over the remainder of the bottle surface until the smallest diameter portion is snugly and evenly engaged by the contracting sleeve. The machine produces sleeve wrapped bottles of this type in which the defects of folds in the sleeve or wavy top margins are avoided. The centrifugal force component provided by controlled bottle rotation (150-200 RPM) in the apparatus maintains the material of the sleeve opposite any of the smaller diameter portions of the bottle billowed out to give the resin time to react with the heat supplied by the oven and shrink into place evenly and without wavy tops or wrinkles.
Other advantages and features of the invention will be more readily apparent to those skilled in the art from the following detailed description of the drawings, which illustrate an apparatus for carrying out the method of the invention, on which:
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a three-quarter side perspective view, in part schematic, showing the machinery and process for making a plastic wrapped bottle, and including the apparatus of this invention;
FIG. 2 is a detailed perspective view showing a bottle carried by the bottle conveyor of the apparatus through an oven for heating and shrinking the plastic sleeve thereon;
FIG. 3 is an end view, partly in section, of the bottle receiving the sleeve of heat shrinkable plastic from a mandrel device of the sleeve making apparatus;
FIG. 4 is the first in a sequence of end views of the bottle and sleeve in which the plastic sleeve is undergoing shrinking in an oven under the utilization of the invention;
FIG. 5 is the second in a sequence of end views showing the bottle and sleeve at a later stage during the heating in the oven;
FIG. 6 is the third in a sequence of end views showing the final plastic wrap on the bottle;
FIG. 7 is an end sectional elevational view of the apparatus shown on FIG. 2.
DESCRIPTION OF THE INVENTION
Shown on FIG. 1 is a machine for producing plastic sleeves on a turret machine 10, assembling them telescopically over glass bottles 11 carried by the conveyor 12 and shrinking them thereon in a heating apparatus 13. The glass bottles in the example of the present disclosure, after having a shrunken plastic covering thereon, form a plastic wrapped container of a type described and shown in the above mentioned U.S. Pat. No. 3,760,968, as shown on FIG. 14, thereof.
Again referring to FIG. 1, in production of these containers, glass bottles 11 are picked up by the neck chucks 14 spaced along the endless bottle conveyor 12 and carried through over 13, indicated generally in phantom outline on FIG. 1. After receiving a sleeve of the plastic material herein described, the conveyor path extends through the length of the oven chamber which is operated as a hot air chamber kept at elevated temperature by radiant heaters of sufficient magnitude for shrinking the plastic cylinder-like sleeve onto the bottle.
The plastic material used is a polyolefin or copolymers of olefins, for example polyethylene, or laminates of polyolefins, e.q. polyethylene foam layer and polyethylene film or a polystyrene foam and ethylene ethyl acrylate film.
The plastic material of the polyolefin foam is made in sheet that is highly oriented in the longitudinal dimension (M direction) of the web which is to become the circumference of the sleeve. There may be some orientation in the cross dimension of the web (T direction); however, this should be minimal in relation to the M direction orientation, because this T direction is ultimately the height dimension of the sleeve and it is desirable to control the top margin of the wrap level and at a line along the bottle.
Examples of plastic sheet material that may be run in a web 15 are foamed polyethylene on the order of 0.010-0.020 inch thickness and highly oriented in the running (M) direction of web 15. M direction orientation for shrinkage should be at least 30% and on the order of 60-80% is preferred. The cross (T) direction orientation should be less than 15% and in the range 0-15%.
In a more general way, the plastic sheet material may be a form of a contractible polyolefin or copolymer of olefins with vinyl esters, for example, vinyl acetate, or with alpha, beta, monoethylenically unsaturated acids, such as ethyl acrylate or ethylene ethyl acrylate. The plastic is preferably in form of a foam sheet or a foam/film laminate sheet, but the principles of the invention will also work with non-foam materials or solid sheet.
The general properties of the described materials in contraction (shrinking) is to achieve upon heating a first pliable, plastic state (a very limp condition) at which time the sheet material tends to sag, slump or fold, and this is followed after additional heating rather suddenly by a shrinkage reaction.
In assembly of the plastic sleeve onto a bottle, the inner circumference of sleeve 16 is just slightly more than the exterior circumference of the bottle 11 at its largest portion, usually the body portion, so that the sleeve may be telescopically assembled over bottle 11 to the proper elevation on the latter.
Referring again to FIG. 1, the web 15 of plastic sheet is mounted in a roll supply and unwound to a feed drum 18 which cuts the web into lengths for forming the sleeves 16 (FIG. 3). The feed drum, in turn, feeds each of the cut lengths of the plastic to a mandrel 17 on the turret machine 10. These components are more specifically shown and described in U.S. Pat. No. 3,802,942.
Once the plastic is on the mandrel 17 and wound around it so that the ends of the plastic overlap, a heated seal bar (not shown herein) of the turret machine 10 presses the overlapped plastic into a heat bonded, vertical seam securing the ends and making a substantially cylindrical sleeve 16. A stripper device 19 is shifted along mandrel 17 which transfers the plastic sleeve onto the overhead bottle 11.
Bottles 11 are loaded from an infeed conveyor 20 to the chucks 14 of the endless conveyor 12. The conveyor path is described at one end by the two end gears 21 and 22 on shaft 23 that is coaxial with the center shaft of turret machine 10, and at the other end by the two gears 24 and 25 which rotate about shaft 26. The conveyor 12 is made up of chains 27 and 28 reeved on the end gears 23, 24 and 22, 25, respectively. The bottle chucks 14 pick up the bottles at the loading station over bottle infeed conveyor 20 and are carried as parts of the assembly of the conveyor 12. Included on the conveyor are carriage brackets carried by the chains 27, 28 along which the cylinder assembly 30 is slidably mounted. The height elevation of the chucks 14 in the conveyor path is controlled by a cam roller 31 which operates on the upper cam track 32. The opening and closing movement of the jaws of chuck 14 are controlled by cam roller 33 running in the cam track 34. Thusly, the bottles 11 are picked up in succession by the bottle conveyor and carried in the path A indicated by the line and arrows on FIG. 1. This path includes a registration of each bottle with an underlying sleeve of the plastic material which is pushed upwardly by stripper 19 over the bottle. The bottle with sleeve thereon next proceeds to oven 13 to be heated and processed in accordance with the present invention. As the sleeve 16 reaches its assembled height on bottle 11, the conveyor path A extends along a watercooled sleeve support bar 35 which extends from adjacent the mandrel path on turret machine 10 well into the oven 13. The structural details of support bar 35 is disclosed in copending application Ser. No. 658,631 filed Feb. 17, 1976, U.S. Pat. No 4,012,271, owned by a common assignee with the present application. The support bar 35 will assure the elevation of the sleeve on the bottle at least until such time as shrinkage of a degree similar to that illustrated on FIG. 4 is achieved in the oven 13. In this state, the contractible sleeve has shrunken to engage at least an annular portion of the major body (large diameter) of bottle 11 to hold the sleeve in place during the balance of the process.
The bottle 11, illustrated on FIGS. 2-7, is typical of carbonated beverage bottles in use today. Referring to the bottle on FIG. 3, which is the same as shown on the other Figures, it includes a major diameter body portion 11a, a rounded shoulder portion 11b at the upper end of the body which merges into the minor diameter neck portion 11c. The neck 11c may, as is illustrated, include a carrying ring 11d molded in the glass. Above ring 11d the neck merges into the bottle finish 11e which includes an annular rim 11f at the top of the bottle defining the opening or mouth for filling and pouring. At the other end of bottle 11, the side wall of body 11a merges into the bottom wall 11g at the corner radius or heel portion 11h. By the term "major diameter" it is meant the larger cross dimension of the bottle; and, by the term "minor diameter" it is meant a substantially lesser cross dimension of the bottle than said major diameter. As an example, the bottle may have a body 11a of a diameter on the order of 4-5 inches, a major diameter, and the neck 11c below the ring 11d is a minor diameter on the order of 1-2 inches. The sleeve 16 is placed to an assembled position, as shown on FIG. 3, encircling the body and neck portions of the bottle so that the top edge 16a of the sleeve is at least within about 1/2 inch of the finish 11e. In the example shown, this locates the edge 16a at about the elevation of the lower margin of the ring 11d of the bottle.
After the bottle and sleeve enter oven 13 (FIG. 1), the chuck is positively driven by a belt or chain drive means controlled to impart rotation to the bottle sufficient such that centrifugal forces bearing on the sleeve in the portions encircling the lesser or minor diameter portions of the bottle area of sufficient magnitude to hold the sleeve erect as the polyolefin is heated and becomes soft and pliable. As the sleeve material reaches its shrink temperature, the initial shrinkage should occur at the body portion 11a of the bottle. The sleeve will be shrunken into contact with the wall of the body of bottle 11 in the middle areas first. This is best accomplished by having the glass bottle preheated to elevated temperature (100°-250° F) and by applying the oven heat so that it is concentrated first around the body portion and next toward the top and bottom edges of the sleeve, i.e. edges 16a and 16b.
The rotation of the bottle while traveling in the oven is performed by the apparatus to be described. Referring to FIG. 2, each bottle chuck 14 has its upper cylinder 30 slidably mounted in the slides 29a of bracket 29 for vertical movement of the cylinder under control of the cam roller 33 and cam track 34. The bracket 29 is fastened to upper and lower carriage chains 27 and 28 and includes a roller 36 running in the track 37 extending around the endless path on the machine.
As seen on FIG. 7, track 37 is fastened to the structural framework 45 of the machine. So that the path of carriage 29 will not wobble, the upper and lower C-shaped bosses 46 for connecting the carriage 29 to chains 27 and 28 each also include a stub shaft 47 and rotatable roller 48. Each roller 48 runs in a similar guide track 49 fastened to the stationary main frame 45. Track 49 follows the path of the chain at least in the portions of the endless path wherein the process is being performed. This structure adds stability to the bottle carriage mechanism. Accordingly, the carriage bracket 29 travels the endless path corresponding to that of chains 27 and 28 and is pulled by the chains connected thereto. The cylinder 30 of each chuck assembly is manipulated vertically along bracket 29 by the cam roller 33, cam 34 for placing the chuck 14 at the proper elevation in the various process steps of handling of the bottle.
As seen on FIG. 7, the chucks jaws 14 are pivoted open and closed about a bottle finish 11e by a yoked piston 38 carrying the cam roller 31. As mentioned before, roller 31 engages a cam 32 controlling the open or close position of the chuck jaws 14. The piston 38 slides vertically in cylinder 30 and is limited by a pin 39 extending through the wall of cylinder 30. The underside of piston 38 engages a chuck rod 40 which extends axially of cylinder 30 and connects to the chuck support collar 41. Collar 41 is pivotally supported on the end of a hollow shaft 42 and the chuck rod 40 extends through the hollow shaft 42. Shaft 42 is mounted in bearings in cylinder 30 such that the shaft and chuck support collar 41 plus the chuck jaws 14 are rotatable. Chuck rod 40 is spring loaded at the underside of piston 38 such that rod 40 is normally extended upwardly in riding the cam roller 31 in contact with the cam 32.
The chuck support collar 41 includes a rotary driven element 43 which in the illustration on the drawings, is a pulley driven by the powered endless member 44 in mesh or driving contact therewith. The member 44, in the illustrated example herein, is a V-belt. The element 43 and member 44 could take the form of a sprocket and link chain, such as a bicycle-type chain. The belt member 44 is driven in a manner to be presently described such that the pulley 43 and the chuck support collar 41 and chuck jaws 14 attached thereto are driven in a controlled speed of rotation during the portion of travel of the sleeve and bottle in the oven wherein the sleeve is undergoing shrinkage.
Referring to FIG. 1, the belt 44 is reeved about an end pulley 50 rotatably mounted on the machine frame and about the drive pulley 51 on the power transmission unit 52. Along the active span of belt 44 there are several freely rotatable back-up rollers 53 which extend over the span of travel for the chucks while in the oven. The back-up rollers 53 may be located on about a 6-inch spacing of their centers along this span of the belt. The back-up rollers 53 are spring loaded against the belt, such as is illustrated on FIG. 2, which hold the belt into the path of the pulleys 43 on each of the chucks and assure driving engagement of the belt 44 with the pulleys 43. An end idler pulley 54 guides the belt over the drive pulley 51. An adjustable take-up pulley 55 is rotatably mounted on an adjustable means (not shown) on the back side of the belt run to maintain the belt in a taut condition.
Transmission unit 52 is a reversible, variable speed type operated by an electric motor 56 connected to the transmission input sprocket 57 by a chain drive 58. Transmission 52 is preferably operated to run the belt in a direction counter to the direction of travel of the chucks through oven 13, that is, on FIG. 1 in a clockwise direction (the carriage chains 27, 28 are being driven in a counter clockwise direction). In this fashion, the line speed of the chucks through the oven will be additive with the speed of belt 44 and their sum will provide the rotation to the chucks in the oven for the purposes of the invention. The running speed of the belt 44 may be varied through the motor and transmission to achieve the desired RPM of the chucks as they travel through the oven.
The path of belt 44 will be controlled by the series of back-up rollers 53 such that the belt 44 will engage each of the pulleys 43 approximately at the time the bottle carried by the chuck enters the front end of oven 13. At this point, the elevation of the chuck cylinders 30 is established by cam track 34 such that each of the pulleys 43 will mesh with belt 44. The prescribed rotational speed of the chuck and bottle, determined by line speed of conveyor 12 and running speed of belt 44, will be achieved in the forward end of the oven atmosphere for size of bottle and dimensions and composition of the cylindrical form of sleeve thereon. As the bottle passes to and in the oven, the lower edge 16b of the sleeve will be guided on water cooled bar 35 so as to maintain proper height elevation of the sleeve on the bottle.
Referring now to the sequence of FIGS. 3-6, the method of shrinking the polyolefin type of sleeve on the bottle is illustrated. As seen on FIG. 3, the sleeve is moved telescopically along the central axis of bottle 11 by the UP motion of stripper element 19 so as to transfer the cylindrical sleeve 16 from the mandrel 17 and into the assembled position. The bottle and sleeve then move into the oven and the sleeve is exposed to the heating needed for shrinking. In the use of polyethylene sleeves, the operating temperature of the oven is in the range 600°-900° F under production conditions of approximately 100-250 BPM.
In the oven 13, the heat is supplied by hot air or infra-red burners and directed onto the bottle as it passes along the oven in a pattern indicated on FIGS. 4 and 5. The heat pattern is indicated thereon by the encircled H legend plus the arrows. The forward section of the oven directs the heat as shown on FIG. 4 toward the body section 11a of the bottle. After polyolefin material is being elevated in temperature to a degree necessary for shrinking, the sleeve becomes limp. However, by this time the bottle and sleeve are brought up to a rotational speed to apply centrifugal force to the upper and lower segments 16c and 16d, respectively, of the sleeve material which force maintains the sleeve erect and these unsupported end segments 16c and 16d are billowed outwardly as shown on FIG. 3. In the example given, such as a glass bottle preheated to 110°-125° F having a body diameter at 11a of 4-5 inches and a neck diameter at 11c of 1-2 inches, and using a foamed polyethylene matrix with solid polyethylene exterior skin of 1-3 mils thickness, the composite thickness being 14-15 mils, and wherein the circumferential (M.D.) shrink factor or orientation is 60-80% and the height (C.D.) shrink factor is 0-15%, the bottle rotation of 250-275 RPM produces a centrifugal force sufficient to achieve the billowed effect of the sleeve segments 16c and 16d while the intermediate segment is shrinking onto the bottle. As the bottle passes into the next adjacent part of oven 13, the heat is applied or directed onto the bottle in accordance with the pattern shown on FIG. 5 (represented by the encircled H legend and arrows), wherein heat is now concentrated against the upper segment 16c and the lower segment 16d of the sleeve. Rotation of the bottle continues while these segments achieve temperature for shrinking and undergo the contraction until the material thereof shrinks snugly along the wall of the bottle at the neck section 11c and over the heel section 11h and onto the annular bearing section of the bottom wall 11g.
After the sleeve has finally achieved the full shrunken condition, the product of the bottle and sleeve is shown on FIG. 6. The top marginal edge 16a of the sleeve has now snugly encircled the neck just under the ring 11d; whereas, the bottom marginal edge 16b has curled under the bottom of the bottle and encircled the heel radius portion 11h. The top and bottom margins of the wrap are free of wavy and wrinkled appearance. The sleeve wrapped bottle (indicated as F on FIGS. 1 and 6) has a relatively tough, cushioned covering on the exterior surface that is in a snug fitting, conforming engagement substantially encapsulating the bottle. Only the carrying ring 11d, finish portion 11e and central area of bottom 11g are left uncovered. The need for exposure of these surfaces in the use of the bottle should be readily apparent.
At the point of production illustrated on FIG. 6, the wrapped bottle F exits the oven and rotation of the chuck and bottle ceases by a disengagement of the belt 44 with pulley 43, which will occur naturally by the diverging path of belt 44 between the last back-up roller 53 and the guide roller 54 from engaging the pulley 43 of the chucks traveling along the path prescribed by the carriage chains 27 and 28. As shown schematically by the line and arrow path on FIG. 1, each chuck cylinder 30 lowers the chuck jaws 14 by sliding downwardly along the carriage bracket under control of roller 33 which is following the dip in cam 34. The cam 34 lowers the bottle such that it is nearly engaging the exit conveyor 59. At this time, the roller 31 controlling the opening-closing movement of chuck jaws 14 encounters the sharp dip in cam 32 opening the jaws and releasing the bottle product F to the exit conveyor 59. Thereafter, the chuck mechanism and carriage conveyor repeat the cycle upon passing the loading point over the bottle infeed conveyor 20.
Referring again to FIG. 2, the apparatus illustrates the travel of the bottle in the forward section of oven 13 wherein the heat is being directed predominantly toward the body section 11a of the bottle. The one half portion of the oven 13 shown represents the exhaust half side 13b of the oven in which the central louver controlled slots 60 control the flow of heat across the oven into the intermediate zone of the bottle and along the path of the bottle thereat. In this section, the central louvers of slots 60 control major flow of the heated air across the intermediate region of the bottle path. By the same principle, the next stages of the oven will include top and bottom bottle zone exhaust slots 61 that direct the heated air principally toward heating the top and bottom regions of the bottle in its path through the aft section of the oven. Together these serially arranged oven sections apply the heat for shrinking the sleeve in accordance with the patterns described and illustrated on FIGS. 4 and 5.
As shown on FIG. 7, the bottle is moving toward the observer and the heating is applied in this cross-sectional view from the left hand one half of the heating apparatus 13a housing burners (not shown) across the top and bottom zones over the upper and lower billowed portions 16c and 16d of the sleeve and into the exhaust one half of the oven 13b, just described.
As mentioned earlier, the sleeves may be made from sheet stock of a pre-oriented polyolefin or copolymers of olefins, for example polyethylene of either high density or low density grade, or laminates of polyolefins, e.g. polyethylene foam layer and polyethylene film. The property of these materials in contraction (heat shrinking) is a first pliable or limp state during which the sheet of the sleeve tends to sag, slump or fold easily, followed by a shrinkage reaction. This invention deals effectively with the propensity of the material of the type described to slump or sag in the initial stages of heating by improving or making it feasible for the material of the sleeve to shrink evenly over the bottle surface when it reaches a temperature to do so and without wrinkles, such that the bottle is covered up to the finish end, along the neck and on the body to the bottom annular bearing surface.
The preheating of the glass bottle, indicated herein as beneficial in the process, is accomplished just prior to the telescopic assembly of the cylindrical sleeves thereover. This may be done in an oven placed along the path of the conveyor after the bottle loading station, or hot bottles from the manufacturing line producing the bottles may be presented to the loading station at proper elevated temperature. The hot glass or heat in the bottle glass is especially beneficial in the shrinkage of the foam sheet materials in sleeve form over the bottle surface.
Having described a preferred embodiment of the invention and illustrated in connection therewith a preferred form of apparatus for carrying out the method of the invention, it should be understood that further modifications may be resorted to without departing from the spirit of the invention and scope of the appended claims. | An apparatus for forming a smooth, even, substantially encapsulating layer of a heat shrinkable polyolefin plastic on a glass container. The body of the container is substantially greater in diameter compared with the neck. A cylindrical sleeve of polyolefin is telescopically placed along the outer surface of the container and the two are conveyed together into a heating oven for shrinking the sleeve snugly over the container. During heating, the polyolefin initially softens and becomes limp such that the sleeve tends to fold over or upon shrinking creates wavy top margins on the shrunken covering. The apparatus provides controlled rotation of the bottle and sleeve in the oven to apply a centrifugal force to the limp plastic which remains erect and billowed outwardly to give the material time to react with the heat such that the sleeve material shrinks into overall even, snug contact about the contour of the container without folds and wrinkles. By way of example, using 14-15 mil foam polyethylene sleeve on the order of 4-5 inch diameter over a bottle having a body diameter 4-5 inch and neck diameter 1-2 inch, the foam being pre-oriented in machine direction (sleeve circumference) 60- 80% and cross dimension 0-15% is subjected to a bottle rotation in the range of 150-300 RPM while immersed in the oven heated by hot air at a ware production rate (speed) of 100-250 BPM. | 1 |
This non-provisional application claims the benefit of Provisional Appl. Ser. No. 60/561,864, entitled “FAST PARAMETRIC NON-RIGID IMAGE REGISTRATION BASED ON FEATURE CORRESPONDENCES,” filed on Apr. 12, 2004.
BACKGROUND OF THE INVENTION
The present invention relates generally to medical imaging, and more particularly, to an efficient deformable registration methodology using a B-spline based free-form deformation model. The method utilizes sparse feature correspondences to estimate an elastic deformation field in a closed form. In a multi-resolution manner, the method is able to permit the recovery of small to large non-rigid deformations, such that the resulting deformation is globally smooth and guaranteeing one-to-one mapping between two images being registered.
Non-rigid (i.e., deformable) registration is an active and important topic of research in medical imaging. This process has numerous clinical applications, such as, for example, the study of PET-CT chest images and MR kidney perfusion time series, where respiratory motion causes gross changes in shape of the organs. It is employed in computational anatomy to adapt an anatomical template to individual anatomies. It is also used in brain imaging for spatial normalization of functional images, group analysis, and the like. Despite vast research efforts, however, non-rigid registration remains a primarily academic interest, and is not currently used in industry.
The reasons for the lack of industrial use are varied. State-of-the-art non-rigid registration methods are relatively slow, with running times on a typical workstation on the order of minutes to hours. Furthermore, most non-rigid registration methods do not directly solve the problem of anatomical correspondences. In many registration algorithms, maximum image similarities are pursued, and correspondences are only generated somewhat as a byproduct at the end of the registration. This poses problems when it comes to validation, since correct anatomical correspondences are the ultimate goal of a good registration method, as opposed to the ability and accuracy to transform one image into a clone of the other image. Finally, there is still no widely accepted validation protocol for measuring the quality of a deformation field generated by a registration method. For most available algorithms, no formal justification for the uniqueness of the solution is provided.
Existing methods for non-rigid registration fall into three general categories: feature-based registration, intensity-based registration, and hybrid methods that integrate the former. Feature based models utilize anatomical knowledge in determining sparse feature correspondences. These can be the faster of the implementations. The well-known disadvantage with this procedure is the need for user interaction to select good features for determining feature correspondences. Compared to rigid-registration, more features are necessary in non-rigid registration in order to recover a dense local deformation field, thus demanding a more automatic and principled method for extracting features, finding correspondences, and estimating elastic deformation. Intensity based methods are much more widely used in non-rigid registration. See, e.g., D. Rueckert, L. I. Sonda, C. Hayes, D. L. G. Hill, M. O. Leach, and D. J. Hawks, “Nonrigid Registration Using Free-Form Deformations: Application to Breast MR Images,” IEEE Transactions on Medical Imaging, Vol. 18, No. 8, pp. 712-721, August 1999. They can be fully automated without prior feature extraction. Typically a dense local deformation field is recovered by optimizing certain energy functions. A regularization term is usually included to explicitly force the smoothness of the deformation field. However, the intensity-based methods do not directly solve the anatomical correspondence problem. Another major concern with this method is that it tends to be very slow. By not discriminating good image elements (e.g., salient anatomical boundary features) from poor ones (e.g., noise, pixels/voxels in homogeneous regions that induce correspondence ambiguity), the cost functions to be optimized are often complex and non-convex, thereby making optimization prone to be stuck in local minima. Hybrid methods aim to integrate the merits of the feature-based and intensity-based models. See, e.g., D. Shen and C. Davatzikos, “Hammer: Hierarchical Attribute Matching Mechanism for Elastic Registration,” IEEE Transactions on Medical Imaging, Vol. 21, No. 11, pp. 1421-1439, November 2002; J. Kybic and M. Unser, “Fast Parametric Elastic Image Registration, IEEE Transactions on Image Processing [need cite]. These have been the subject of greater interest in recent times.
One important aspect of non-rigid registration is the choice of the local transformation (deformation) model. In the prior art, both parametric and non-parametric models have been considered. In parametric local deformation models, the thin-plate spline model and free form deformation model are most popular. In non-parametric models, elastic deformation and viscous fluid models are commonly employed.
SUMMARY OF INVENTION
In view of the foregoing, it is an object of the invention to provide a system and methodology that utilizes an efficient non-rigid registration algorithm that can register large volumes of data and time series in real time or near to real time.
It is another object of the invention to provide a system and methodology that utilizes a non-rigid registration algorithm that provides for a recovered deformation field that guarantees good anatomical correspondences.
It is yet another object of the invention to provide a system and methodology that utilizes a non-rigid registration algorithm that is easily adaptable to multi-modalities and images of different anatomical structures.
It is still another object of the invention to provide a system and methodology that utilizes a non-rigid registration algorithm that is robust to image noise, intensity change and inhomogeneity, partial occlusion and missing parts.
It is yet another object of the invention to provide a system and methodology that utilizes a non-rigid registration algorithm that assures consistent results regardless of which image is treated as the fixed image and which image is treated as the moving image.
It is still another object of the invention to provide a system and methodology that utilizes a non-rigid registration algorithm that provides for a recovered deformation field that should ideally conform to the actual biomechanical deformations within the tissue of interest.
It is yet another object of the invention to provide a system and methodology that utilizes a non-rigid registration algorithm that provides for a recovered deformation field that can detect where structure appears or disappears between the fixed and moving images.
In accordance with an aspect of the present invention, there is provided a system and methodology for non-rigidly registering a fixed to a moving image utilizing a B-Spline based free form deformation (FFD) model. The methodology utilizes sparse feature correspondences to estimate an elastic deformation field in a closed form. In a multi-resolution manner, the method is able to recover small to large non-rigid deformations. The resulting deformation field is globally smooth and guarantees one-to-one mapping between the images being registered. The method generally comprises the steps of: detecting feature points on the fixed image and feature points on the moving image; assigning a feature vector to each feature point; calculating the dissimilarity of each pair of feature vectors for feature pairs on the fixed image and the moving image; calculating the correspondence between feature pairs based on dissimilarity measure: X i and X i ′; solving for a dense deformation field P using a closed form FFD model; and transforming the moving image and the feature points on the moving image using a current FFD deformation field estimate. In accordance with another aspect of the present invention, there is provided a memory medium containing program instructions which, when executed by a processor, enable a computer to implement the foregoing method.
These and other advantages of the invention will be apparent to those of ordinary skill in the art by reference to the following detailed description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic of a computer system for carrying out a preferred embodiment of the invention;
FIG. 2 a is a flowchart of a method in accordance with the invention;
FIG. 2 b is an exemplary fixed image and a set of feature points thereon;
FIG. 2 c is an exemplary moving image corresponding to the fixed image depicted in FIG. 2 b and the set of detected feature points on the moving image which correspond to a set of feature points on the moving image; and
FIG. 3 is a comparison of the recovered space deformation and ground truth deformation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 depicts an operating environment for an illustrated embodiment of the present invention, comprising a computer system 100 for implementing non-rigid image registration. The system 100 includes a conventional computer 102 , comprising a processing unit 104 , a system memory 106 , and a system bus 108 that couples the various system components including the system memory to the processing unit 104 . The processing unit is of conventional design and includes a typical arithmetic logic unit (ALU) 110 for performing computations, a collection of registers 112 for temporary storage of data and instructions, and a control unit 114 as is well known in the art. The system bus 108 may be any of several types of bus structures including a memory bus or memory controller, peripheral bus, and a local bus using any of a variety of bus architectures. The system memory 106 includes read only memory (ROM) and random access memory (RAM). The system memory 106 further includes a basic input/output system (BIOS) which contains the basic routine that helps to transfer information between elements in computer 102 . The computer 102 further includes data storage 116 which may comprise a hard disk drive, magnetic disk drive, optical disk drive or the like and the appropriate interfaces to the system bus 108 . The drives and their associated computer-readable media provide non-volatile storage of computer readable instructions, data structures, program modules and other data for the computer 102 . A number of program modules may be stored on the hard disk, magnetic disk, optical disk, ROM or RAM, including an operating system, one or more application programs, other program modules, and program data. The application programs may include a computer program 117 adapted for carrying out the methodology of the invention as discussed in greater detail hereinbelow. A user of the system can enter commands via a keyboard 118 coupled to the system bus 108 through a serial or USB interface 120 . The computer may be provided with a network interface 122 to enable networked communication with a remote computer(s) 124 . The remote computer can be a personal computer, server, router, network PC, peer device or other common network node. A display 126 is coupled to the system bus 108 through a video adapter 128 in a conventional manner.
Referring now to FIG. 2 a , there is depicted a flowchart of a method of using a non-rigid registration algorithm in accordance with an aspect of the present invention to register a fixed image ( FIG. 2 b ) on the computer display ( 126 depicted in FIG. 1 with a moving image on the computer display depicted in FIG. 2 c . In accordance with this method, it is assumed that a proper rigid registration algorithm has been applied to bring the two images into rough spatial alignment. An exemplary rigid registration algorithm is disclosed in the following publication: C. Xu, X. Huang, Y. Sun, C. Chefdhotel, J. Guehring, F. Sauer, V. Sebastion, “A Hybrid Rigid Registration Model for 2D/3D Medical Images,” Invention Disclosure, Siemens Corporate Research, Inc., August 2003. The inventive method consists of . . . is sufficient.
In order to utilize similarity measures for finding local correspondences, suppose a local window centered at a feature point is W, the fixed image is f, and the moving image is m. The first multi-modal similarity measure is the Squared Normalized Cross Correlation:
R = ( ∑ ( i , j ) ∈ w ( f ( i , j ) - ( f _ ) ) ( m ( i , j ) - ( m _ ) ) ∑ ( i , j ) ∈ w ( f ( i , j ) - ( f _ ) ) 2 ∑ ( i , j ) ∈ w ( m ( i , j ) - ( m _ ) ) 2 ) 2
where f denotes the mean intensity value in the local window on the fixed image, and m is the mean intensity value in a local window on the moving image. Another similarity measure is the Local Mutual Information, where we denote the intensity probability distribution in the small window in the fixed image or volume as p f , and that in the testing window in the moving image or volume as p m . With the joint density as p f,m , the local mutual information is defined as
MI
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As described briefly above, given a set of corresponding points between the fixed image and the moving image, we model the deformation using a Cubic B-spline FFD model, which is a space deformation model that deforms an object by manipulating a regular control lattice P overlaid on the volumetric embedding space. In the registration problem, the inverse inference problem is considered, in which the deformations between images are solved with respect to the control lattice coordinates that are parameters of FFD. The following describes the closed-form FFD based registration method in detail.
Considering a regular lattice of control points:
P m,n =( P m,n x ,P m,n y ); m= 1, . . . , M,n=1 , . . . ,N
overlaid to an image region
Γ={ x }={( x,y )|1≦ x≦X, 1 ≦y≦Y}
Denote the initial configuration of the control lattice as P 0 , and the deforming control lattice as P=P 0 +δP. Under these assumptions, we consider the FFD parameters are the deformations of the control points in both directions (x,y);
Θ={(δ P m,n x ,δP m,n y )};( m,n )∈[1 ,M]×[ 1 ,N]
Given the deformation of the control lattice from P 0 to P, the deformed location L(x)=(x′,y′) of a pixel x=(x,y), is defined in terms of a tensor product of a Cubic B-spline:
L ( x ) = x + δ L ( x ) = ∑ k = 0 3 ∑ l = 0 3 B k ( u ) B l ( v ) ( P i + k , j + l 0 + δ P i + k , j + l )
where, by definition:
x = ∑ k = 0 3 ∑ l = 0 3 B k ( u ) B l ( v ) P i + k , j + l 0
are the initial coordinates of the pixel x.
δ L ( x ) = ∑ k = 0 3 ∑ l = 0 3 B k ( u ) B l ( v ) δ P i + k , j + l
is the incremental deformation at pixel x,
δP i+k,j+l , (k,l)∈[0,3]×[0,3], in which
i = ⌊ x X · ( M - 1 ) ⌋ + 1
and
j = ⌊ y Y · ( N - 1 ) ⌋ + 1 ,
consists of the deformations of pixel x's (sixteen) adjacent control points,
B k (u) is the k th basis function of the Cubic B-spline given by;
B 0 ( u )=(1 −u ) 3 /6 , B 1 ( u )=(3 u 3 −6 u 2 +4)/6 B 2 ( u )=(−3 u 3 +3 u 2 +3 u+ 1)/6, B 3 ( u )= u 3 /6
with
u = x X · M - x X _ · M π _ · B l ( v )
is similarly defined.
From the equation above, we have:
L ( x ) - x = ∑ k = 0 3 ∑ l = 0 3 B k ( u ) B l ( v ) δ P i + k , j + l
In accordance with the inventive method for efficient non-rigid image registration, we pick n feature sample points x i =(x i , y i ), i=1, . . . ,n, from the target (fixed) image ( FIG. 2 b ), and find their correspondences x i ′=(x i ′, y i ′), on the source (moving) image ( FIG. 2 c ). In a typical 256*256 image, n can range from several hundred to several thousand, and can be chosen depending on the estimated intrinsic resolution of the image deformation to be recovered Assuming x i ′ is the deformed location L(x), then the relationship between the two point sets can be depicted in a matrix equation format as follows:
U=Sp
where, U is the displacement matrix between the correspondence pairs:
U = ( x 1 ′ - x 1 y 1 ′ - y 1 x 2 ′ - x 2 y 2 ′ - y 2 ⋮ ⋮ x n ′ - x n y n ′ - y n ) n × 2 ,
S is the Cubic B-spline basis matrix:
S = ( … … [ b i 1 + 0 , j 1 + l ] … [ b i 1 + 1 , j 1 + l ] … [ b i 1 + 2 , j 1 + l ] … [ b i 1 + 3 , j 1 + l ] … ⋰ ⋰ ⋰ ⋰ ⋰ … [ b i c + 0 , j c + l ] … [ b i c + 1 , j c + l ] … [ b i c + 2 , j c + l ] [ b i c + 3 , j c + l ] … … ⋰ ⋰ ⋰ ⋰ ⋰ … … [ b i n + 0 , j n + l ] … [ b i n + 1 , j n + l ] … [ b i n + 2 , j n + l ] … [ b i n + 3 , j n + l ] … ) ,
And p is comprised of the FFD parameters in a matrix:
( δ P 1 , 1 x δ P 1 , 1 y δ P 1 , 2 x δ P 1 , 2 y ⋮ ⋮ [ δ P i c + 0 , j c + l x ] [ δ P i c + 0 , j c + l y ] ⋮ ⋮ [ δ P i c + 1 , j c + l x ] [ δ P i c + 1 , j c + l y ] ⋮ ⋮ [ δ P i c + 2 , j c + l x ] [ δ P i c + 2 , j c + l y ] ⋮ ⋮ [ δ P i c + 3 , j c + l x ] [ δ P i c + 3 , j c + l y ] ⋮ ⋮ δ P M , N x δ P M , N y ) ( M × N ) × 2.
In the B-Spline basis matrix S, c=1, . . . , n is the index of a corresponding pair, and [b i c +k,j c +l ] is the abbreviation for:
[ b i c +k,j c +l ]=( B k ( u c ) B 0 ( v c ) B k ( u c ) B 2 ( v c ) B k ( u c ) B k ( v c ) B k ( u c ) B 3 ( v c )).
In the FFD parameter p matrix, [δP i c +k,j c +l ] is the abbreviation for:
[ δ P i c + k , j c + l ] = ( δ P i c + k , j c + 0 δ P i c + k , j c + 1 δ P i c + k , j c + 2 δ P i c + k , j c + 3 ) ,
and the column indices of a [b i c +k,j c +l ] in S are the same as the row indices as a [δP i c +k,j c +l ] in matrix p. Thus, based on this parametric free form transformation model, a closed form solution for the control lattice deformation can be solved utilizing Singular value Decomposition efficiently as:
p • = S + U
In real applications, since the process of finding the correspondences introduces errors, the solution to the foregoing is the Ordinary Least Squares (OLS) solution to the problem:
p minimize ∑ i = 1 n x i ′ - L ( p ; x ) .
This approach efficiently recovers relatively large to local non-rigid deformations utilizing sparse feature correspondences in closed form. The resulting deformation field has been demonstrated to be globally smooth, and minimizes the distance between the target feature points and transformed source feature points. FIG. 3 is a comparison of the recovered space deformation and ground truth deformation for the exemplary images depicted in FIGS. 2 b and 2 c . In this example, the moving image is a phantom image generated by artificially deforming the regular control lattice. Accordingly, the ground-truth deformed control lattice that originally generated the moving image is known. By comparing the deformation field recovered by the registration method disclosed herein with the ground truth deformation, the accuracy of the registration method is known.
The present invention has been shown and described in what are considered to be the most practical and preferred embodiments. It is anticipated, however, that departures may be made therefrom and that obvious modifications will be implemented by those skilled in the art. It will be appreciated that those skilled in the art will be able to devise numerous arrangements and variations which, although not explicitly shown or described herein, embody the principles of the invention and are within their spirit and scope. | A method and system for non-rigidly registering a fixed to a moving image utilizing a B-Spline based free form deformation (FFD) model is disclosed. The methodology utilizes sparse feature correspondences to estimate an elastic deformation field in a closed form. In a multi-resolution manner, the method is able to recover small to large non-rigid deformations. The resulting deformation field is globally smooth and guarantees one-to-one mapping between the images being registered. The method generally comprises the steps of: detecting feature points on the fixed image and feature points on the moving image; assigning a feature vector to each feature point; calculating the dissimilarity of each pair of feature vectors for feature pairs on the fixed image and the moving image; calculating the correspondence between feature pairs based on the dissimilarity measure; solving for a dense deformation field P using a closed form FFD model; and transforming the moving image and the feature points on the moving image using a current FFD deformation field estimate. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/081,967, filed on Jul. 18, 2008, which is incorporated herein by reference in its entirety. This application is related to U.S. patent application Ser. No. 12/505,195, filed on Jul. 17, 2009, entitled “METHODS AND SYSTEMS FOR DNA ISOLATION ON A MICROFLUIDIC DEVICE,” and naming Michele R. Stone as the inventor, which application is incorporated herein by reference in its entirety.
BACKGROUND
1. Field of the Invention
The present invention relates to methods and systems for microfluidic DNA sample preparation. More specifically, embodiments of the present invention relate to methods and systems for the isolation of DNA from patient samples on a microfluidic device and use of the DNA for downstream processing, such as performing amplification reactions and thermal melt analysis on the microfluidic device.
2. Description of Related Art
The detection of nucleic acids is central to medicine, forensic science, industrial processing, crop and animal breeding, and many other fields. The ability to detect disease conditions (e.g., cancer), infectious organisms (e.g., HIV), genetic lineage, genetic markers, and the like, is ubiquitous technology for disease diagnosis and prognosis, marker assisted selection, correct identification of crime scene features, the ability to propagate industrial organisms and many other techniques. Determination of the integrity of a nucleic acid of interest can be relevant to the pathology of an infection or cancer. One of the most powerful and basic technologies to detect small quantities of nucleic acids is to replicate some or all of a nucleic acid sequence many times, and then analyze the amplification products. Polymerase chain reaction (PCR) is perhaps the most well-known of a number of different amplification techniques.
PCR is one of the more sensitive methods for nucleic acid analysis. However, many substances in clinical samples, including blood, can affect PCR and can result in substantial error in the PCR results. Thus, DNA isolation and purification are critical to methods for DNA analysis. Conventional DNA preparation requires large volume samples and requires a long process time. Microfluidic technology makes it possible to use much less sample and less time for DNA sample preparation. Solid phase extraction methods have been applied in DNA sample preparation. DNA is selectively extracted on the solid phase while other substances in the sample are washed out of the extraction column. For instance, Breadmore et al. ( Anal Chem 75(8): 1880-1886, 2003) reported on a microchip-based DNA purification method using silica beads packed into glass microchips and immobilized within a sol-gel. Alternatively, DNA isolation can be achieved by nuclei size sieving.
Since DNA only exists in the nuclei of cells, DNA samples can be prepared by selectively isolating nuclei from the sample. Traditional nuclei isolation is slow and has low efficiency. Generally, nuclei isolation is performed by selective lysis of cellular membranes while keeping the nuclei intact. Nuclei are then isolated by centrifuge, sediment or sieving. Dignani et al. ( Nucl Acids Res 11: 1475-1489, 1983) reported isolation of nuclei from samples by centrifugation. U.S. Pat. No. 5,447,864 discloses a method of isolating nuclei using a DNA mesh. U.S. Pat. No. 6,852,851 discloses a method of isolating nuclei in a microfabricated apparatus that contains a plurality of radially dispersed micro-channels. U.S. Pat. No. 6,992,181 describes the use of a CD device for the purification of DNA or cell nuclei. This method requires moving parts and centrifugal force to isolate DNA and or cell nuclei, using a barrier in the channel to impede flow of DNA and nuclei. Palaniappan et al. ( Anal Chem 76:6247-6253, 2004) reported a continuous flow microfluidic device for rapid erythrocyte lysis. VanDelinder et al. ( Anal Chem 78:3765-3771, 2006) reported a separation of plasma from whole human blood in a continuous cross-flow in a molded microfluidic device. To increase mixing of lysis buffer with blood sample in microfluidic channel, Palaniappan et al. ( Anal Chem 78:5453-5461, 2006) reported a microfluidic channel with the channel floors that are patterned with double herringbone microridges. VanDelinder et al. ( Anal Chem 79:2023-2030, 2007) describe a perfusion in microfluidic cross-flow for particles and cells. Particles flow in the main channel while a perfusion flows through the side channels to exchange the medium of suspension.
There are several problems with current technology of purifying DNA by isolating nuclei from cells. First, the conventional approach is slow. Usually, the conventional approach takes hours to finish from cell lysis to the nuclei isolation. For example, the purification process described in U.S. Pat. No. 6,852,851 is carried out in a plurality of micro channels with a mesh built into the micro channel. However, because the size of micro channels is limited, the process can treat only limited sample sizes from 100 nl to 1 μl. Another problem is with the method of releasing DNA and/or nuclei from membrane. For example, DNAse is used in U.S. Pat. No. 5,447,864 to release nuclei from membrane. However, the addition of DNAse will fail the down stream process. In U.S. Pat. No. 5,447,864, sodium dodecyl sulfate solution or proteinase K is used to disrupt the nuclear envelope in order to release DNA. However, these lysis reagents will also seriously inhibit the downstream process. The conventional nuclear lysis method is to use high concentration sodium chloride (0.5 M) to disrupt the nuclear membrane. However, the high concentration sodium chloride will also inhibit the downstream process.
In addition, the current technologies require specific buffers for DNA binding and washing, most of which are not compatible with down stream applications such as PCR. These technologies also have a wide range of efficiencies in the overall quantity of DNA that is purified. This can be a significant problem when samples are to be used in microfluidics. The multiple reagents that are typically required for DNA purification would demand that moving parts, such as valves, be constructed into a microfluidic device for the introduction of multiple reagents in a solid phase extraction. In a microfluidic system, solid phase extraction or the use of multiple reagents is complicated and can lead to system failures.
Although the various methods exist to capture nuclei for use in down stream application or to separate specific cells from a sample population, none of these methods describes a single device that is capable of extracting cell nuclei and isolating the nucleic acid contained in the cell nucleic that is suitable for microfluidic processing and down stream processes such as amplification reactions and detection analysis. Thus, there is a need to develop microfluidic systems and methods for DNA isolation.
SUMMARY OF THE INVENTION
The present invention relates to methods and systems for microfluidic DNA sample preparation. More specifically, embodiments of the present invention relate to methods and systems for the isolation of DNA from patient samples on a microfluidic device and use of the DNA for downstream processing, such as performing amplification reactions and thermal melt analysis on the microfluidic device.
In one aspect, the present invention provides a method of purifying DNA from a sample (e.g., a patient sample or other sample) in a microfluidic device. According to this aspect, the method comprises: (a) mixing the sample and a lysis buffer in a mixing region of a microfluidic device; (b) selectively lysing the cellular membranes of cells in the sample without lysing the nuclear membranes of cells in a cell lysing region of the microfluidic device to produce intact nuclei from the cells; (c) trapping the intact nuclei from the sample on a membrane in a cell trapping region of the microfluidic device while allowing other components of the sample to flow through the membrane and into a waste collection region of the microfluidic device; (d) lysing the intact nuclei trapped on the membrane; (e) releasing the DNA from the lysed nuclei; and (f) collecting the released DNA in a DNA collection region of the microfluidic device.
In some embodiments, the sample is a patient sample which could be, for example, a blood sample, a urine sample, a saliva sample, a sputum sample, a cerebrospinal fluid sample, a body fluid sample or a tissue sample which contain white blood cells. In other embodiments, the patient sample comprises white blood cells. In additional embodiments, the patient sample is first enriched for white blood cells prior to the selective lysis of the cellular membrane. In some embodiments, the enrichment of white blood cells is performed by filtration. In additional embodiments, the enrichment of white blood cells is performed using antibodies. In some embodiments, the antibodies are coupled to a solid phase, such as beads, magnetic beads, particles, polymeric beads, chromatographic resin, filter paper, a membrane or a hydrogel.
In some embodiments, the selective lysis is performed by contacting the patient sample, either whole or after white blood cell enrichment, with a buffer (referred to herein as a lysis buffer or nuclei isolation buffer) that selectively permeabilizes cellular membranes while leaving the nuclei of the cells intact. Nuclei isolation buffers that have these characteristics are well known to the skilled artisan. Products that include nuclei isolation buffers for selectively lysing cellular membranes are commercially available. Suitable commercial products that include such buffers, include, but are not limited to, Nuclei EZ Prep Nuclei Isolation Kit (NUC-101) (Sigma, St. Louis, Mo., USA), Nuclear/Cytosol Fractionation Kit (K266-100) (BioVision Research Products, Mountain View, Calif., USA), NE-PER Nuclear and Cytoplasmic Extraction Reagents (Pierce, Rockville, Ill., USA), Nuclear Extraction Kit (Imgenex, Corp., San Diego, Calif., USA), Nuclear Extract Kit (Active Motif, Carlsbad, Calif., USA), and Qproteome Nuclear Protein Kit (Qiagen, Valencia, Calif., USA). See also, U.S. Pat. Nos. 5,447,864, 6,852,851 and 7,262,283. It is known that the type of nuclei in question may determine which nuclei isolation buffer will be required. See, U.S. Pat. No. 5,447,864 for a discussion of factors that can be optimized for preparing a suitable selective lysis buffer for different cell types.
In one embodiment, the lysis buffer is a hypotonic buffer. For example, a commercial hypotonic lysis buffer can be purchased from Sigma Aldrich, Nuclei EZ lysis buffer (N 3408). A kit is also available from Sigma Aldrich, Nuclei EZ Prep Nuclei Isolation Kit (Nuc-101). A common recipe for a 10× hypotonic solution is, 100 mM HEPES, pH 7.9, with 15 mM MgCl 2 and 100 mM KCl. In another embodiment, the lysis buffer is a hypotonic buffer that comprises a detergent. Suitable detergents include, but are not limited to ionic detergents, such as lithium lauryl sulfate, sodium deoxycholate, and Chaps, or non-ionic detergents, such as Triton X-100, Tween 20, Np-40, and IGEPAL CA-630. In another embodiment, the lysis buffer is an isotonic buffer. For example, Sigma Aldrich offers a kit, CelLytic Nuclear Extraction kit, which contains an isotonic lysis buffer. A common recipe for a 5× isotonic lysis buffer is, 50 mM Tris HCl, pH 7.5, with 10 mM MgCl 2 , 15 mM CaCl 2 , and 1.5M Sucrose. In an additional embodiment, the buffer is an isotonic buffer that comprises a detergent which may be an ionic detergent or a non-ionic detergent. In other embodiments, the selective lysis is performed using a hypotonic lysis buffer that contains a weak detergent. In further embodiments, the patient sample and the hypotonic lysis buffer are mixed in a 1:1 ratio. In additional embodiments, the selective lysis of the cellular membranes totally lyses red blood cells.
In some embodiments, the steps of lysing the intact nuclei trapped on the membrane and releasing the DNA from the lysed nuclei comprise flowing an elution buffer over the intact nuclei trapped on the membrane.
In some embodiments, the elution buffer is a buffer in which the DNA is compatible. In other embodiments, elution buffer comprises a Tris buffer, KCl and a zwitterion. In one embodiment, the zwitterion is betaine, trimethylamine-N-oxide, trimethylamine hydrochloride or trimethylamine bromide. In other embodiments, the elution buffer is an amplification reaction buffer that may contain the non-assay specific amplification reagents. In additional embodiments, the amplification reaction buffer is a PCR buffer that may contain the non-assay specific PCR reagents. In further embodiments, the elution buffer contains a dye that binds to DNA. In additional embodiments, the dye is useful for quantifying the amount of DNA in the channel. In additional embodiments, the nuclei are lysed by heat to release the DNA from the nuclei. In some embodiments, the nuclei are subjected to heat prior to an amplification reaction. In other embodiments, the nuclei are subjected to heat during the amplification reaction and the nuclei lysis region is the initial region of microfluidic device in which the amplification reaction is conducted.
In some embodiments, the intact nuclei trapped on the membrane are lysed by applying heat to the trapped nuclei. In one embodiment, the trapped nuclei are heated for approximately 1 to 10 minutes at a temperature in the range of approximately 35° C. to 95° C. In another embodiment, the trapped nuclei are heated for approximately 7 minutes at a temperature of approximately 50° C. In a further embodiment, the DNA released from the lysed nuclei flows to the DNA collection region of the microfluidic device by flowing an elution buffer over the DNA. In some embodiments, the elution buffer is as described herein.
In another aspect, the present invention provides a microfluidic device for purifying DNA from a patient sample. In accordance with this aspect, the microfluidic device comprises a sample port and lysis buffer port in fluid communication with a mixing region of the microfluidic device. The mixing region is configured to permit mixing of a patient sample from the sample port and lysis buffer from the lysis buffer port. The microfluidic device also comprises a cell lysis region in fluid communication with the mixing region. The cell lysis region is configured to permit the lysis buffer to selectively lyse cellular membranes of cells in the patient sample without lysing nuclear membranes of the cells to produce intact nuclei from the cells in the patient sample. The microfluidic device further comprises a nuclei trapping region wherein intact nuclei from the patient sample are trapped on a membrane while other components of the patient sample flow through the membrane and into a waste collection region of the microfluidic device. The nuclei trapping region is in fluid communication with the cell lysis region. The microfluidic device also comprises a nuclei lysis region in which the nuclear membranes of the intact nuclei are lysed to release the DNA. The microfluidic device further comprises a DNA collection region in the microfluidic device wherein DNA released from the trapped intact nuclei is collected.
In some embodiments, the microfluidic device further comprises an elution buffer port in fluid communication with the nuclei trapping region and the nuclei lysing region. The elution buffer from the elution buffer port can be controlled to flow through the nuclei trapping region and the nuclei lysing region to lyse the nuclear membranes of the trapped intact nuclei to release the DNA. In one embodiment, the elution buffer is one in which the DNA is compatible. In other embodiments, elution buffer comprises a Tris buffer, KCl and a zwitterion. In one embodiment, the zwitterion is betaine, trimethylamine-N-oxide, trimethylamine hydrochloride or trimethylamine bromide. In other embodiments, the elution buffer is an amplification reaction buffer that may contain the non-assay specific amplification reagents. In additional embodiments, the amplification reaction buffer is a PCR buffer that may contain the non-assay specific PCR reagents.
In some embodiments, the microfluidic device further comprises a heat source which is configured to provide heat to the intact nuclei in the nuclei lysis region sufficient to lyse the nuclear membranes thereby releasing the DNA. In one embodiment, the heat source is controlled to heat the nuclei for approximately 1 to 10 minutes at a temperature in the range of approximately 35° C. to 95° C. In another embodiment, the heat source is controlled to heat the nuclei for approximately 7 minutes at a temperature of approximately 50° C.
In some embodiments, the DNA released from the lysed nuclei flows to the DNA collection region of the microfluidic device by flowing an elution buffer over the DNA. In other embodiments, the membrane is made of silicon, glass, polymers, polyester, polycarbonate or nitrocellulose. In additional embodiments, the membrane has a round or rectangular shape. In one embodiment, the membrane has a pore size from approximately 500 nm to 10 μm. In another embodiment, the membrane has a pore size from approximately 0.5 μm to 10 μm.
In some embodiments, the microfluidic device comprises multiple layers. In one embodiment, the microfluidic device further comprises: (1) a first layer comprising the lysis buffer port, the patient sample port, an elution buffer port, a purified DNA collection port and a waste port; (2) a second layer comprising a network of microchannels that transports the lysis buffer solution and the patient sample to the mixing region of the microfluidic device; (3) a third layer comprising a network of microchannels; (4) the membrane located between the second and third layers. In some embodiments, the patient sample and the lysis buffer solution mix in the mixing region and flow in the microchannels to the cell lysis region, and wherein the patient sample and the lysis buffer solution flow from the cell lysis region to the membrane in the nuclei trapping region, and wherein the other components of the patient sample flow through the membrane and into a microchannel in the third layer and to the waste collection region of the microfluidic device, and wherein the DNA released from the nuclei flows through the membrane and into a microchannel located in the third layer and to the DNA collection region.
In other embodiments, the microfluidic device further comprises: (1) a first layer comprising the lysis buffer port, the patient sample port, an elution buffer port, a purified DNA collection port and a waste port; (2) a second layer comprising a network of microchannels that transports the lysis buffer solution and the patient sample to the mixing region of the microfluidic device; (3) a third layer comprising a hole through which fluid flows from the microchannels in the second layer and onto the membrane; (4) a fourth layer comprising a hole through which fluid flows from the membrane and into microchannels located in a fifth layer, therein the fifth layer further comprising the waste collection region and the DNA collection region.
In another aspect, the present invention provides another microfluidic device for purifying DNA from a patient sample. In accordance with this aspect, the microfluidic device comprises a cell lysis region configured such that a lysis buffer is permitted to mix with the patient sample resulting in the selective lysing of cellular membranes of cells in the patient sample without lysing nuclear membranes of the cells to produce intact nuclei from the cells in the patient sample. The microfluidic device also comprises a cross-flow filtration region in which intact nuclei are separated from other components of the patient sample by a filter. The filter has a pore size such that the intact nuclei do not pass through the filter and the other components of the patient sample pass through the filter and are carried away by a cross-flow buffer that is controlled to flow through the cross-flow filtration region. The microfluidic device further comprises an interface channel in fluid communication with said cross-flow filtration region through which purified nuclei flow for downstream analysis.
In some embodiments, the cross-flow filtration region comprises a microfluidic separation channel in fluid communication with the cell lysis region and configured to receive the intact nuclei and the other components of the patient sample from the cell lysis region. The filter is constructed in the microfluidic channel. The cross-flow filtration region also comprises a cross-flow buffer port configured to permit the cross-flow buffer to flow across the microfluidic separation channel and through the filter. The cross-flow buffer, as it flows across the separation channel, facilitates removal of the other contents of the patient sample from the separation channel through the filter. The intact nuclei flow through the separation channel.
In some embodiments, the flow of one of the lysed patient sample and the cross-flow buffer is driven by a pressure differential and the flow of the other of the lysed patient sample and cross-flow buffer is driven by an electrophoretic voltage potential. In one embodiment, the pore size of the filter is between approximately 2 μm to 10 μm. In another embodiment, the pore size of the filter is approximately 5 μm. In one embodiment, the filter is a membrane. In another embodiment, the filter is an array of pillars that forms as size exclusion barrier.
In some embodiments, the cross-flow filtration region is configured to separate the intact nuclei, bacteria and viruses from the lysed patient sample. In one embodiment, the cross-flow filtration region comprises a first filter to separate the intact nuclei, a second filter to separate bacteria and a third filter to separate viruses. In another embodiment, the first filter is located closest to a cross-flow buffer port, the second filter located next closest to the cross-flow buffer port, and the third filter located furthest from the cross-flow buffer port. In a one embodiment, the pore size of the first filter is between approximately 2 μm to 10 μm, the pore size of the second filter is between approximately 0.2 μm to 2 μm, and the pore size of the third filter is between approximately 10 nm to 400 nm. In another embodiment, wherein the pore size of the first filter is approximately 8 μm, the pore size of the second filter is approximately 0.4 μm, and the pore size of the third filter is approximately 100 nm.
In some embodiments, the microfluidic device further comprises more than one cross-flow filtration region in which each cross-flow filtration region receives a portion of the lysed patient sample from the cell lysis region, and each cross-flow filtration region is in fluid communication with one or more interface channels. In one embodiment, the filter of one cross-flow filtration system has a pore size that is different from the pore size of one other cross-flow filtration system.
In some embodiments the microfluidic device further comprises a nuclei concentration region in which the intact nuclei from the cross-flow filtration region are concentrated. In one embodiment, the nuclei concentration region comprises a concentration channel having a sample input section, a sample outlet section and a wall portion configured to prevent intact nuclei from flowing through said wall portion and to allow the other contents of the patient sample to flow through said wall portion. In one embodiment, the wall portion is a filter. In another embodiment, the filter comprises a set of pillars placed along the concentration channel.
In some embodiments, the patient sample is as described herein. In other embodiments, the patient sample comprises white blood cells. In further embodiments, the downstream analysis comprises an amplification reaction in which nucleic acid is amplified and/or a detection procedure for determining the presence or absence of an amplified product.
In another aspect, the present invention provides a microfluidic system for purifying DNA from a patient sample. In accordance with this aspect, the microfluidic system comprises a microfluidic device. The system also comprises a cell lysis region in the microfluidic device configured such that a lysis buffer is permitted to mix with the patient sample resulting in the selective lysing of cellular membranes of cells in the patient sample without lysing nuclear membranes of the cells to produce intact nuclei from the cells in the patient sample. The system further comprises a cross-flow filtration region in the microfluidic device in which intact nuclei are separated from other components of the patient sample by a filter. The filter has a pore size such that the intact nuclei do not pass through the filter and the other components of the patient sample pass through the filter and are carried away by a cross-flow buffer that is controlled to flow through the cross-flow filtration region. The system also comprises a nuclei lysis region in the microfluidic device in which the nuclear membranes of the intact nuclei are lysed to release the DNA. The nuclei lysis region is in fluid communication with the cross-flow filtration region. The system also comprises an amplification reaction region in the microfluidic device in which the nucleic acid is amplified and a detection region in the microfluidic device for determining the presence or absence of an amplified product.
In some embodiments, the nuclei lysis region is part of the amplification reaction region. In other embodiments, the regions are in separate microfluidic devices. In one embodiment, the cell lysis region, the cross-flow filtration region, and the nucleic lysis region are in one microfluidic device and the amplification region and the detection region are in a second microfluidic device.
In another aspect, the present invention provides a method for purifying DNA from a patient sample in a microfluidic device. In accordance with this aspect, the method comprises mixing a patient sample containing cells and a lysis buffer in a mixing region of said microfluidic device. The lysis buffer selectively lyses cellular membranes without lysing nuclear membranes. The method also comprises selectively lysing in a cell lysing region of the microfluidic device the cellular membranes of the cells in the patient sample without lysing the nuclear membranes of the cells to produce intact nuclei from the cells. The method further comprises separating the intact nuclei from the patient sample in a cross-flow filtration region of said microfluidic device. The cross-flow filtration region comprises a filter having a pore size such that the intact nuclei do not pass through the filter and the other components of the patient sample pass through the filter and are carried away by a cross-flow buffer that is controlled to flow through the cross-flow filtration region. The method also comprises flowing purified nuclei through an interface channel in fluid communication with said cross-flow filtration region for downstream analysis.
In some embodiments, the method further comprises driving the flow of one of the lysed patient sample and the cross-flow buffer by a pressure differential and driving the flow of the other of the lysed patient sample and the cross-flow buffer by an electrophoretic voltage potential. In other embodiments, the method further comprises separating the intact nuclei, bacteria and viruses from the lysed patient sample in said cross-flow filtration region in which each of the intact nuclei, bacteria and viruses are released into separate channels with the cross-flow buffer. In another embodiment, the method further comprises separating the intact nuclei, bacteria and viruses from the lysed patient sample in said cross-flow filtration region by a series of filters each having a different pore size. In another embodiment, the method further comprises concentrating the intact nuclei prior to sending the intact nuclei for downstream analysis. In some embodiments, the method further comprises separating the intact nuclei from the lysed patient sample utilizing more than one cross-flow filtration region, each receiving a portion of the lysed patient sample. In some embodiments the patient sample is as described herein. In other embodiments, purifying DNA from cells in a patient sample comprises purifying DNA from white blood cells in the patient sample.
In another aspect, the present invention provides a method of determining the presence or absence of a nucleic acid in a patient sample. In accordance with this aspect, the method comprises mixing a patient sample containing cells and a lysis buffer in a mixing region of said microfluidic device. The lysis buffer selectively lyses cellular membranes without lysing nuclear membranes. The method also comprises selectively lysing in a cell lysing region of the microfluidic device the cellular membranes of the cells in the patient sample without lysing the nuclear membranes of the cells to produce intact nuclei from the cells. The method further comprises separating the intact nuclei from the patient sample in a cross-flow filtration region of the microfluidic device. The cross-flow filtration region comprises a filter having a pore size such that the intact nuclei do not pass through the filter and the other components of the patient sample pass through the filter and are carried away by a cross-flow buffer that is controlled to flow through the cross-flow filtration region. The method also comprises lysing the nuclei to release the nucleic acid in the microfluidic device. The method further comprises amplifying the nucleic acid in the microfluidic device; and determining the presence or absence of an amplified product. The presence of the amplified product indicates the presence of the nucleic acid in the patient sample.
In some embodiments, the patient sample is as described herein. In other embodiments the patient sample contains white blood cells. In additional embodiments, the method further comprises enriching the patient sample for white blood cells prior to the selective lysis of the cellular membranes. The enrichment for white blood cells can be performed as described herein. In further embodiments, the mixing of the patient sample and lysis buffer, selectively lysing, separating intact nuclei and lysing the nuclei are performed in one microfluidic device and the amplification and detection are performed in a second microfluidic device. In other embodiments, the mixing of the patient sample and lysis buffer, selectively lysing and separating intact nuclei are performed in one microfluidic device and the lysing the nuclei, amplification and detection are performed in a second microfluidic device.
In another aspect, the present invention provides another microfluidic system for isolating DNA from cells in a patient sample. In accordance with this aspect, the microfluidic system comprises a lysis buffer storage device for storing a lysis buffer in which the lysis buffer selectively lyses cellular membranes without lysing nuclear membranes. The system also comprises an elution buffer storage device for storing an elution buffer. The system further comprises a sample card having multiple chambers for receiving the patient sample. Each chamber in the sample card comprises an inlet, a filter and an outlet. The system also comprises a flow control system for controlling flow of the lysis buffer and the elution buffer to each chamber of the sample card. The flow control system controls the flow of lysis buffer into each chamber of the sample card such that the lysis buffer selectively lyses cellular membranes to release nuclei and cell debris causing the cell debris to flow through the filter into a waste receptacle positionable beneath the sample card and without lysing nuclear membranes of nuclei in the patient sample which become trapped on the filter. The system further comprises a temperature control system for heating the filter in the sample card sufficient to lyse nuclei trapped on said filter and release DNA. The system also comprises an interface chip comprising multiple DNA sample wells and DNA sample outlets. The interface chip is positionable beneath the sample card and is configured to receive the DNA released from the lysed nuclei trapped on said filter. The system further comprises a main controller in communication with the temperature control system, and the flow control system.
In some embodiments, the temperature control system comprises a heating source and a heat sensor. In other embodiments, the flow control system comprises a pump and a solution delivery chip, wherein the solution delivery chip comprises multiple channels for delivering lysis buffer and elution buffer to each chamber of the sample card. In further embodiments, the flow control system further comprises a pressure control system. The pressure control system comprises an air source, a pressure sensor for controlling the delivery of the elution buffer and the lysis buffer to each chamber of the sample card. In some embodiments, the multiple chambers of the sample card are in fluid communication with one another. In other embodiments, the sample card is disposable. In some embodiments, the sample card is configured to contain multiple different patient samples. In other embodiments, the sample card is configured to contain one patient sample in multiple chambers.
In another aspect, the present invention provides a microfluidic system for determining the presence or absence of a nucleic acid in a patient sample. In accordance with this aspect, the microfluidic system comprises a microfluidic device comprising a sample preparation region, an amplification reaction region and a detection region. The sample preparation region comprises a lysis buffer storage device for storing a lysis buffer in which the lysis buffer selectively lyses cellular membranes without lysing nuclear membranes. The sample preparation region also comprises an elution buffer storage device for storing an elution buffer. The sample preparation region further comprises a sample card having multiple chambers for receiving the patient sample. Each chamber comprises an inlet, a filter and an outlet. The sample card is removably insertable into said sample preparation region of said microfluidic device. The sample preparation region also comprises a flow control system for controlling flow of the lysis buffer and the elution buffer to each chamber of said sample card. The flow control system controlling the flow of lysis buffer into each chamber of the sample card such that the lysis buffer selectively lyses cellular membranes to release nuclei and cell debris causing the cell debris to flow through the filter into a waste receptacle positionable beneath the sample card and without lysing nuclear membranes of nuclei in the patient sample which become trapped on the filter. The sample preparation region further comprises a temperature control system for heating the filter in the sample card sufficient to lyse nuclei trapped on said filter and release DNA. The sample preparation region also comprises an interface chip comprising multiple DNA sample wells and DNA sample outlets, wherein said interface chip is positionable beneath the sample card and is configured to receive the DNA released from the lysed nuclei trapped on said filter. The microfluidic system further comprises a main controller in communication with the temperature control system, the flow control system, and the microfluidic chip. In one embodiment, the main controller controls the flow of DNA from the interface chip to the amplification region and/or the detection region of the microfluidic chip.
In some embodiments, the temperature control system comprises a heating source and a heat sensor. In other embodiments, the flow control system comprises a pump and a solution delivery chip in which the solution delivery chip comprises multiple channels for delivering lysis buffer and elution buffer to each chamber of the sample card. In some embodiments, the multiple chambers of the sample card are in fluid communication. In other embodiments, the flow control system further comprises a pressure control system, wherein the pressure control system comprises an air source, a pressure sensor for controlling the delivery of the elution buffer and the lysis buffer to each chamber of the sample card. In some embodiments, the multiple chambers of the sample card are in fluid communication in which a patient sample in one chamber can be driven into other chambers. In other embodiments, the sample card is disposable.
In another aspect, the present invention provides a method for isolating DNA from cells in a patient sample. In accordance with this aspect, the method comprises providing a microfluidic system comprising (i) a sample card having multiple chambers for receiving the patient sample, wherein each chamber comprises an inlet, a filter and an outlet, said sample card being removably insertable into said microfluidic system, (ii) a flow control system for controlling flow of a lysis buffer and an elution buffer to each chamber of the sample card, (iii) a temperature control system for heating the filter in the sample card; (iv) a waste receptical positionable beneath the sample card, and (v) an interface chip comprising multiple DNA sample wells and DNA sample outlets, wherein said interface chip is positionable beneath the sample card.
The method also comprises loading the patient sample into the chambers of the sample card. The method further comprises inserting the sample card into the microfluidic system. The method also comprises delivering lysis buffer to the chamber of the sample card and selectively lysing cellular membranes of the patient sample without lysing nuclear membranes of nuclei, producing a solution comprising lysis buffer, intact nuclei and cellular debris. The method further comprises controlling the flow control system to drive the lysis buffer and the cellular debris through the filter and into the waste receptacle, thereby trapping the intact nuclei on the filter. The method also comprises controlling the temperature control system to heat the filter causing the intact nuclei trapped on the filter to lyse, thereby releasing DNA. The method further comprises delivering an elution buffer to the chambers of the sample card. The method also comprises controlling the flow control system to drive the elution buffer and the DNA to the DNA sample wells in the interface chip. In some embodiments, the lysis buffer is repeatedly delivered to the chambers of the sample card to clean the filters.
The above and other embodiments of the present invention are described below with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated herein and form part of the specification, illustrate various embodiments of the present invention. In the drawings, like reference numbers indicate identical or functionally similar elements.
FIG. 1 is a functional block diagram of a DNA preparation and analysis system.
FIG. 2 shows a schematic illustration of a microfluidic DNA sample preparation device in accordance with an embodiment of the invention.
FIG. 3A illustrates a multi-layered microfluidic sample preparation device in accordance with an embodiment of the invention.
FIG. 3B is a longitudinal cross-sectional view of a multi-layered microfluidic sample preparation device in accordance with an embodiment of the invention.
FIG. 3C is a transverse cross-sectional view of a multi-layered microfluidic sample preparation device in accordance with an embodiment of the invention.
FIG. 4 is an exploded view of a multi-layered microfluidic sample preparation device in accordance with an embodiment of the invention.
FIG. 5 illustrates a top view of layer 1 of the microfluidic sample preparation device of FIG. 4 .
FIG. 6 is a longitudinal cross-sectional view of layer 1 of the microfluidic sample preparation device of FIG. 4 .
FIG. 7 illustrates a top view of layer 2 of the microfluidic sample preparation device of FIG. 4 .
FIG. 8 illustrates a top view of layer 3 of the microfluidic sample preparation device of FIG. 4 .
FIG. 9 is a longitudinal cross-sectional view of layer 3 of the microfluidic sample preparation device of FIG. 4 .
FIG. 10 illustrates a top view of layer 4 of the microfluidic sample preparation device of FIG. 4 .
FIG. 11 is a longitudinal cross-sectional view of layer 4 of the microfluidic sample preparation device of FIG. 4 .
FIG. 12 illustrates a top view of layer 5 of the microfluidic sample preparation device of FIG. 4 .
FIG. 13 is a longitudinal cross-sectional view of layer 5 of the microfluidic sample preparation device of FIG. 4 .
FIG. 14 is a flow chart illustrating a process according to an embodiment of the invention.
FIGS. 15A and 15B show trapping of nucleic by the membrane. FIG. 15A shows the membrane before trapping the nuclei. FIG. 15B shows the membrane after trapping the nuclei which are dyed with a fluorescence dye.
FIG. 16 is a graph showing the results of an experiment.
FIG. 17 shows a schematic illustration of a cross-flow microfluidic device for sample preparation in accordance with other embodiments of the present invention.
FIG. 18 shows a schematic illustration of a cross-flow filter in accordance with an embodiment of the present invention.
FIG. 19 shows a schematic illustration of a cross-flow filter in accordance with other embodiments of the present invention.
FIG. 20 shows a schematic illustration of a cross-flow microfluidic device for sample preparation in accordance with further embodiments of the present invention.
FIG. 21 is a transverse cross-sectional view of the cross-flow microfluidic device shown in FIG. 20 .
FIG. 22 illustrates a sample concentrator in accordance with embodiments of the present invention.
FIG. 23 illustrates a system for sample preparation in accordance with other embodiments of the present invention.
FIG. 24 is a flow chart illustrating a process for sample preparation according to an embodiment of the invention.
FIG. 25 is a flow chart illustrating a process for determining the presence or absence of a nucleic acid in a sample according to an embodiment of the invention.
FIG. 26 shows a schematic illustration of a microfluidic device for sample preparation in accordance with other embodiments of the present invention.
FIG. 27 illustrates a sample card in accordance with an embodiment of the invention.
FIG. 28 illustrates a sample card in accordance with another embodiment of the invention.
FIG. 29 illustrates a flow control system in accordance with an embodiment of the invention.
FIG. 30 illustrates a solution delivery chip in accordance with an embodiment of the invention.
FIG. 31 illustrates a pressure control chip in accordance with an embodiment of the invention.
FIG. 32 is a flow chart illustrating a process for sample preparation according to an embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates a microfluidic DNA analysis system 100 according to some embodiments of the invention. As illustrated in FIG. 1 , system 100 includes a DNA sample preparation sub-system 102 (a.k.a., “the sample preparation unit”), a DNA amplification, analysis and detection subsystem 104 , and a main control system 101 . The present application is primarily directed to the sample preparation unit 102 and earlier filed applications describe various embodiments of subsystem 104 (see e.g., U.S. Pat. Pub. Nos. 2008/0003588, 2008/0130971, 2008/0176230, and 2009/0053726, all of which are incorporated herein in their entirety by this reference).
FIG. 2 shows a schematic illustration of a component 200 of sample preparation unit 102 in accordance with an embodiment of the invention. More specifically, FIG. 2 shows a schematic illustration of a microfluidic DNA sample preparation device 200 . As illustrated in FIG. 2 , device 200 comprises a chip 201 , a well 202 formed in chip 201 for storing a lysis buffer, and one or more microfluidic channels 206 formed in chip 201 that fluidly connect well 202 to a mixing region 208 formed in chip 201 , thereby providing a path for the lysis buffer in well 202 to travel to the mixing region 208 . Device 200 also includes a sample well 204 formed in chip 201 for storing a sample to analyzed (e.g., a blood sample). Like well 202 , well 204 is connected in fluid communication with mixing region 208 via one or more channels 205 formed in chip 201 .
Mixing region 208 is configured to permit a sample from well 204 and lysis buffer from well 202 to mix. Mixing region 208 , which my simply be a small channel, is connected in fluid communication with a filter 210 (e.g., a permeable membrane or other filter) disposed in chip 201 via a microfluidic channel 209 formed in chip 201 . In some embodiments, filter 210 is made of any combination of one or more of the following: silicon, glass, polymers, polyester, polycarbonate, and nitrocellulose. Filter 210 may have a round shape, rectangular shape, or other shape. In some embodiments, filter 210 comprises a number of pores and the pore sizes may range from 500 nanometers (nm) to 10 micrometers (um). For example, in some embodiments, the pore sizes range from approximately 0.5 um to 10 um. FIGS. 15 a and 15 b illustrate an exemplary embodiment of filter 210 .
Channel 209 is configured to function as a cell lysis region. That is, channel 209 is configured to permit the lysis buffer from well 202 to selectively lyse cellular membranes of cells in the patient sample from well 204 without lysing nuclear membranes of the cells to produce intact nuclei from the cells in the patient sample. For example, in the cell lysis region red blood cells may be disrupted before reaching the filter 210 while white blood cells are partially lysed such that nuclei are intact when the mixture reaches filter 210 .
As further shown in FIG. 2 , a waste well 212 , a DNA collection well 214 , and an elution buffer well 216 are also formed in chip 201 . Additionally, each of the wells 212 , 214 and 216 are connected in fluid communication with filter 210 via microfluidic channels 213 , 215 and 217 , respectively. In some embodiments, during use, well 216 stores an elution buffer which can be, for example, a Tris buffer, KCl and/or a zwitterion. Main control system 101 , as illustrated in FIG. 1 , can cause the elution buffer to flow into filter 210 .
During use of chip 200 , filter 210 forms a nuclei trapping region wherein the intact nuclei from the sample are trapped by filter 210 while other components of the patient sample flow through filter 210 and into waste collection region 212 . Filter 210 also functions as a nuclei lysis region in which the nuclear membranes of the intact nuclei are lysed to release the DNA. The released DNA is forced to flow to DNA collection region 214 .
As further shown in FIG. 2 , device 200 may include a heat source 250 . Heat source 250 may be formed in or on chip 201 or may be structurally separate from chip 201 . Heat source 250 may be an electrical heater (i.e., a device that converts electrical energy into heat) or other type of heat producer. Heat source 250 may be controlled by a temperature controller 252 , which may be a module of main controller 101 or a separate component that is in communication with main controller 101 . Heat source 250 is controlled, configured and arranged to transfer heat to filter 210 at desired times. For example, when intact nuclei are trapped by filter 210 , heat source 250 may be controlled to cause the transfer of heat to filter 210 , which heat is preferably sufficient to lyse or facilitate the lysing of the nuclear membranes of the nuclei, thereby releasing the DNA contained by the nuclear membranes.
In some embodiments, chip 201 is a multilayer chip. That is, chip 201 may comprise two or more boards. Referring now to FIGS. 3A-3C , a multilayered embodiment of device 200 is illustrated. In the non-limiting embodiment illustrated in FIG. 3A , device 200 includes six layers. However, fewer or more layers also could be used. FIG. 3B shows a longitudinal cross-sectional view of device 200 in accordance with the embodiment shown in FIG. 3A , and FIG. 3C shows a transverse cross-sectional view of device 200 in accordance with the embodiment shown in FIG. 3A .
FIG. 4 illustrates an exploded view of the embodiment of device 200 shown in FIG. 3A . In the first layer (or top layer) 401 , a top view of which is shown in FIG. 5 , wells 202 , 204 and 216 are formed for containing the lysis buffer, sample and elution buffer, respectively. Also formed in layer 401 is a through hole 402 in fluid communication with DNA collector well 214 and a through hole 404 in fluid communication with waste well 212 . In one non-limiting embodiment, layer 401 is preferably approximately five (5) millimeters thick and is made from Poly(methyl methacrylate) (PMMA). Other thicknesses and materials also may be used for this layer in additional embodiments.
As further shown in FIG. 5 and FIG. 6 , which is a longitudinal cross sectional view of layer 401 , well 202 has a port 405 in its bottom surface so that fluid can flow from well into channels 206 . Likewise, well 204 has a port 406 in its bottom surface so that fluid can flow from well 204 into channel 205 . Thus, ports 405 and 406 are in fluid communication with mixing region 208 . Similarly, well 216 has port 407 in its bottom surface so that fluid can flow from well 216 into channel 217 . As shown in FIG. 4 , channels 205 , 206 and 217 are formed in the second layer 411 of device 200 .
FIG. 7 illustrates a top view of second layer 411 . As shown in FIG. 7 , formed in second layer 411 are a mixing region 208 , channel 209 , through holes 413 , 414 and 415 , and closed bottom wells 416 , 417 , and 418 . Channel 209 fluidly connects mixing region 208 with hole 413 so that a lysis buffer and sample mixture, which may be formed in mixing region 208 , can flow into hole 413 and down to the third layer 421 of device 200 . Likewise, channel 217 connects well 418 , which is positioned directly beneath hole 407 of elution buffer well 216 , with hole 413 so that elution buffer can flow from well 216 into hole 413 and down to the third layer of device 200 . Through hole 414 is positioned beneath through hole 404 so that fluid may flow through hole 414 into hole 404 , and through hole 415 is positioned beneath through hole 402 so that fluid may flow through hole 415 into hole 402 . In one non-limiting embodiment, the second layer 411 of device 200 may comprise a 150 micrometer thick cyclic olefin copolymer (COC) film. Other thicknesses and materials also may be used for this layer in additional embodiments.
FIG. 8 illustrates a top view of third layer 421 which includes through holes 422 , 423 and 424 . Through hole 422 is positioned beneath through hole 414 so that fluid may flow through hole 422 into hole 414 , through hole 423 is positioned beneath through hole 413 , so that fluid may flow through hole 413 into hole 423 , and through hole 424 is positioned beneath through hole 415 so that fluid may flow through hole 423 into hole 415 . FIG. 9 shows a longitudinal cross-sectional view of layer 421 . In one non-limiting example, the third layer 421 of device 200 may comprise a 1 millimeter thick PMMA board. Other thicknesses and materials also may be used for this layer in additional embodiments.
FIG. 10 illustrates a top view of fourth layer 431 which includes through holes 432 , 433 and 434 . Through hole 432 is positioned beneath through hole 422 so that fluid may flow through hole 432 into hole 422 , through hole 433 is positioned beneath through hole 423 , so that fluid may flow through hole 423 into hole 433 , and through hole 434 is positioned beneath through hole 424 so that fluid may flow through hole 434 into hole 424 . FIG. 11 shows a longitudinal cross-sectional view of layer 421 . In one non-limiting embodiment, the fourth layer 431 of device 200 may comprise a 1 millimeter thick PMMA board. Other thicknesses and materials also may be used for this layer in additional embodiments.
As shown in FIG. 4 , filter 210 is sandwiched between the third and fourth layers of device 200 . In some embodiments, filter 210 may be made of any combination of one or more of silicon, glass, polymers, polyester, polycarbonate, and nitrocellulose, as described above. In one non-limiting embodiment, filter 210 is approximately 9 mm by 9 mm and has a thickness of approximately 10 μm. The filter may have other thicknesses and dimensions in additional embodiments.
FIG. 12 illustrates a top view of fifth layer 441 . As shown in that figure, closed bottom wells 212 , 443 and 214 are formed on the top surface of layer 441 . Also, microfluidic channel 215 is formed on the top surface of layer 441 as well as channel 213 , which connects well 443 with waste collection well 212 . Closed bottom wells 212 , 443 , and 214 are positioned beneath through holes 432 , 433 , 434 , respectively. FIG. 13 shows a longitudinal cross-sectional view of layer 441 . On one non-limiting embodiment, the fifth layer 441 of device 200 may comprise a 150 micrometer thick COC film. Other thicknesses and materials also may be used for this layer in additional embodiments.
As illustrated in FIG. 4 , the sixth layer of device 200 is a base layer 451 . In one non-limiting embodiment, layer 451 may comprise a 1 millimeter thick board made of PMMA. Other thicknesses and materials also may be used for this layer in additional embodiments. In some embodiments, the third, fourth and sixth layers are removed, thereby creating a three layer device.
Referring now to FIG. 14 , a flow chart illustrating a process 1400 for preparing DNA for analysis using device 200 is shown. Process 1400 may begin in step 1402 , where a sample (e.g., a sample of blood containing white blood cells) is introduced into sample well 204 . In step 1404 , a lysis buffer is introduced into lysis buffer well 202 . In step 1405 , the lysis buffer is forced to flow out of well 202 through port 405 and channel 206 into mixing region 208 . At or about the same time, the sample is forced to flow out of sample well 204 through port 406 and channel 205 into mixing region 208 . In step 1406 , the lysis buffer and sample mix in the mixing region 208 and the mixture is forced to flow to filter 210 via channel 209 . In embodiments where the sample contains white blood cells, the sample may be enriched for white blood cells prior to introducing the sample into mixing region 208 .
While the lysis buffer/patient sample mixture is in channel 209 and travelling towards filter 210 , the lysis buffer selectively lyses the cellular membranes of cells in the patient sample without lysing the nuclear membranes of cells to produce intact nuclei from the cells, as reflected in step 1407 . When the mixture reaches filter 210 , the mixture preferably contains released intact nuclei from the patient sample. In step 1408 , the intact nuclei are trapped by filter 210 while the waste (i.e., other components of the sample and lysis buffer) passes through filter 210 and is forced to travel via channel 213 to waste collection well 212 .
In step 1410 , the intact nuclei trapped on filter 210 are lysed, thereby releasing DNA from the lysed nuclei. In some embodiments, the step of lysing the intact nuclei comprises causing an elution buffer in well 216 to flow to filter 210 via channel 217 and/or heating the trapped nuclei using heater 250 . In some embodiments, the elution buffer comprises a Tris buffer, KCl and/or a zwitterion. In some embodiments, the elution buffer is an amplification reaction buffer. In embodiments where heat is used to lyse the trapped nuclei, the trapped nuclei may be heated at a temperature in the range of approximately 35 degrees centigrade to 95 degrees centigrade for approximately 1 to 10 minutes. For example, in one embodiment, the trapped nuclei may be heated at a temperature in the range of approximately 50 degrees centigrade for approximately 7 minutes.
In step 1412 , after lysing the intact, trapped nuclei, the DNA released from the nuclei is collected in the DNA collection well 214 . For example, the released DNA flows out of filter 210 and to well 214 via channel 215 . In some embodiments, the released DNA flows to well 214 by flowing an elution buffer from well 216 such that the elution buffer flows out of port 407 and into channel 217 , then through channel 217 to and through the filter 210 where the released DNA mixes with the elution buffer, and then flows through channel 215 into well 214 . Once in well 214 , the mixture containing the released DNA and elution buffer can be removed from chip 201 via through holes 402 , 415 , 424 , and 434 , all of which are in fluid communication with well 214 .
While not shown, it is well known in the art that device 200 may be coupled to a flow control system (e.g., a system that comprises one or more pumps) for causing the various buffers, samples and mixtures to flow as described above. Additionally, device 200 may be coupled with a microfluidic platform. The DNA purified by device 200 may be directly delivered by a pump to a well in the microfluidic platform, and further mix with other PCR components.
FIGS. 15A and 15B show trapping of nucleic acid by the membrane in accordance with an embodiment of the present invention. Specifically, FIG. 15A shows fluorescence emitted from membrane prior to the membrane trapping dye stained nuclei, and FIG. 15B fluorescence emitted from membrane after the membrane has trapped dye stained nuclei.
Referring now to FIG. 16 , a graph is provided showing results achieved from using an above-described method. In particular, DNA purification was tested using 9 patient blood samples. After obtaining purified DNA using this method, one fraction of purified DNA sample was quantified by Pico green method (fluorescence based method for measuring total DNA concentration). Another fraction of purified DNA sample was quantified by real time-PCR. The results show that real time-PCR result is comparable to Pico green assay, indicating that no significant amount of inhibits exist in the purified DNA sample.
The table below provides representative dimensions for many of the above described components of device 200 . These dimensions are illustrative and not intended to be limiting in any way.
TABLE 1
Component
Dimensions
chip 201
length: 42 mm; width: 28 mm; height: 8.3 mm
channel 206
length: 28 mm; width: 150 μm; depth: 150 μm
channel 205
length: 5.4 mm; width: 100 μm; depth: 150 μm
channel 209
length: 100 mm; width: 200 μm; depth: 150 μm
channel 213
length: 7.75 mm; width: 400 μm; depth: 150 μm
channel 215
length: 42 mm; width: 100 μm; depth: 150 μm
channel 217
length: 36 mm; width: 100 μm; depth: 150 μm
Referring now to FIG. 17 , a schematic illustration is provided of various components of sample a preparation sub-system 102 according to other embodiments of the present invention. As shown in FIG. 17 , system 102 may include a sample well 1702 for containing a sample (e.g., a sample of blood containing white and red blood cells), a lysis buffer well 1704 for containing a lysis buffer, and a channel 1706 in fluid communication with wells 1702 and 1704 via channels 1703 and 1705 , respectively. Channel 1706 may function as a cell lysis region. That is, channel 1706 may be configured such that the lysis buffer from well 1702 is permitted to mix with the sample from sample well 1704 resulting in the selective lysing of cellular membranes of cells in the sample without lysing nuclear membranes of the cells to produce intact nuclei from the cells in the sample.
As further shown in FIG. 17 , system 102 may include a cross-flow filtration region 1708 in fluid communication with channel 1706 . In some embodiments, in region 1708 intact nuclei (or white cells or other target components) are separated from other components of the sample (e.g., proteins and other PCR inhibitors) by one or more cross-flow filters 1710 , each having a pore size such that the target components (e.g., intact nuclei) are prevented from being carried away by a cross-flow buffer that is controlled to flow through the cross-flow filtration region, but other components of the patient sample flow through filters and are carried away by the cross-flow buffer. In the non-limiting embodiment shown in FIG. 17 , cross-flow filtration region 1708 includes four cross flow filters 1710 that are connected in parallel. In other embodiments, region 1708 may have one, two, three or five or more filters 1710 . Additionally, in some embodiments, some filters 1710 may be arranged in series. Moreover, each filter 1710 may have a different average pore size.
System 102 may also include a concentrator region 1712 , which is in fluid communication with cross flow filtration region 1708 , in which the intact nuclei from the cross-flow filtration region are concentrated. An interface region 1714 may be in fluid communication with concentrator 1712 . As will be explained herein, purified intact nuclei preferably exit concentrator 1712 and enter interface region 1714 , which includes one or more interface channels through which purified nuclei flow for downstream processing and analysis.
FIG. 18 further illustrates an embodiment of cross-flow filter 1710 . As shown in FIG. 18 , cross-flow filter 1710 includes a microfluidic separation channel 1802 , which, as shown in FIG. 17 , is in fluid communication with the cell lysis region 1706 and concentrator 1712 . Channel 1802 is configured such that fluid entering channel 1802 from channel 1706 can flow through channel 1802 such that the fluid will reach and enter the concentration region 1712 . A filter 1810 and a filter 1812 are disposed in a middle portion of channel 1802 . Filters 1810 and 1812 are arranged to form a separation chamber 1814 .
In operation, while the lysis buffer/sample mixture is flowing through channel 1802 (i.e., from the input end 1832 to the output end 1834 ), a cross-flow fluid is introduced into the portion of channel 1802 having the filters 1810 and 1812 via a cross-flow buffer input port 1804 . The cross-flow fluid exits this portion of the channel 1802 via a cross-flow buffer output port 1806 . Advantageously, there is a differential (e.g., a pressure differential or voltage differential, such as an electrophoretic voltage potential, or a gravitational field) between ports 1804 and 1806 that causes the cross-flow fluid that enters channel 1802 via port 1804 to flow first through filter 1810 , then through separation chamber 1814 , then through filter 1812 , and finally out of channel 1802 via exit port 1806 . There is also a force (e.g., pressure, electric, gravity) that causes fluid entering channel 1802 to flow from end 1832 to end 1834 . As the cross-flow buffer flows across separation chamber 1814 (as illustrated by the dashed lines), the cross-flow buffer together with filters 1810 and 1812 facilitate the separation of the intact nuclei from the other components of the mixture that flows into channel 1802 from cell lysis region 1706 . More specifically, the pore size of the filters 1812 and 1810 are such that the intact nuclei do not pass through filter 1812 , but are driven toward the concentrator region 1712 by the flow of fluid from end 1832 to end 1834 , whereas other, smaller components of the sample are driven through filter 1812 and driven towards exit port 1806 via the cross-flow of the cross-flow buffer. In this manner, intact nuclei (or other target material) can be efficiently separated from the other components of the sample. Preferably, one type of force (e.g., air pressure) is used to cause fluid entering channel 1802 to flow from end 1832 to end 1834 , while a different type of force (e.g. an electrical field, gravity) is used to cause the cross-flow fluid to flow from 1804 to 1806 .
In some embodiments, the size of the pores of filters 1810 and 1812 is between approximately 1 um and 15 um. For example, the size of the pores of filter 1812 may be about 5 um. In some embodiments, filters 1810 and 1812 may consists of or include a membrane and/or an array of pillars.
Referring now to FIG. 19 , a cross-flow filter 1710 according to another embodiment is illustrated. As shown in FIG. 19 , cross-flow filter 1710 may include a microfluidic separation channel 1902 . In an exemplary embodiment, filters 1910 , 1912 , 1916 , and 1918 are disposed in a middle portion of channel 1902 . Filters 1910 , 1912 , 1916 , and 1918 are arranged to form separation chambers 1914 a , 1914 b , and 1914 c.
In operation, while the lysis buffer/sample mixture is flowing through channel 1902 (e.g., from the input end 1932 towards an output end 1934 a ), a cross-flow fluid is introduced into the portion of channel 1902 having the filters via a cross-flow buffer input port 1904 . The cross-flow fluid exits the portion of channel 1902 having the filters via a cross-flow buffer output port 1906 . Advantageously, there is a differential (e.g., a pressure differential or voltage differential, such as an electrophoretic voltage potential) between ports 1904 and 1906 that causes the cross-flow fluid that enters channel 1902 via port 1904 to flow first through filter 1910 , then through separation chamber 1914 a , then through filter 1912 , then through separation chamber 1914 b , then through filter 1916 , then through separation chamber 1914 c , then through filter 1918 , and finally out of channel 1902 via exit port 1906 . There is also a differential (e.g., pressure or electric) that causes fluid entering separation chambers 1914 a , 1914 b , and 1914 c to flow towards ends 1934 a , 1934 b , and 1934 c , respectively. As the cross-flow buffer flows across a separation chamber 1914 a , the cross-flow buffer together with the filters that form the separation chamber 1914 a facilitate the separation of desired components (e.g., intact nuclei, bacteria, viruses) from the other components of the mixture that flows into the separation chamber.
More specifically, for example, the pore size of the filters 1912 and 1910 are such that the intact nuclei do not pass through filter 1912 , but are driven toward end 1934 by a differential, whereas other, smaller components of the sample (e.g., bacteria, viruses or waste material) are driven through filter 1912 and into separation chamber 1914 b by the flow of the cross-flow buffer. For example, the average pore size of filter 1912 may be between approximately 1 um and 15 um. In one embodiment, the average pore size is about 8 um.
The pore size of the filter 1916 may be such that bacteria does not pass through filter 1916 , but are driven toward end 1934 b by a differential, whereas other, smaller components of the sample (e.g., viruses) are driven through filter 1916 into separation chamber 1914 c by the flow of the cross-flow fluid. For example, the average pore size of filter 1916 may be between approximately 0.2 um and 2 um. In one embodiment, the average pore size is about 0.4 um. The pore size of the filter 1918 may be such that viruses do not pass through filter 1918 , but are driven toward end 1934 c by a differential, whereas other, smaller components of the sample are driven through filter 1918 and driven towards exit port 1906 via the cross-flow of the cross-flow buffer. For example, the average pore size of filter 1918 may be between approximately 10 nm 400 nm. In one embodiment, the average pore size is about 100 nm. Port 1961 may be used to create a pressure differential between port 1961 and end 1934 b so that a fluid in chamber 1914 b will flow towards end 1934 b . Likewise, Port 1962 may be used to create a pressure differential between port 1962 and end 1934 c so that a fluid in chamber 1914 c will flow towards end 1934 c.
In the above manner, intact nuclei, bacteria and viruses may be separated from the sample collected in separate target collection ports using the cross flow filter 1710 as illustrated in FIG. 19 , in accordance with one embodiment.
Referring now to FIG. 20 , a layered embodiment of filter 1710 in illustrated. As shown in FIG. 20 , a filter 1710 may include three layers: a top layer 2002 , a middle layer 2004 , and a bottom layer 2006 . A filter 2008 may be formed in top layer 2002 , one or more separation channels 2010 may be formed in middle layer 2004 , and a filter 2012 may be formed in bottom layer 2006 . At least a portion of the separation channel 2010 extends from the top surface of layer 2004 to the bottom surface of layer 2004 , as shown in FIG. 21 , which shows a cross sectional view of this embodiment of filter 1710 . As shown in FIG. 21 , layer 2002 is positioned on top of layer 2004 such that filter 2008 is on top of channel 2010 , thereby forming a top, porous wall of channel 2010 . Likewise, as shown in FIG. 21 , layer 2006 is positioned beneath layer 2004 such that filter 2012 is underneath channel 2010 , thereby forming a bottom, porous wall of channel 2010 .
In operation, while the lysis buffer/sample mixture is flowing through channels 2010 (i.e., from the input end 2006 to the output end 2014 ), a cross-flow fluid is introduced into the portion of channel 2010 having the filters 2008 and 2012 via a cross-flow buffer input port (not shown). The cross-flow fluid exits this portion of the channel 2010 via a cross-flow buffer output port (also not shown). As with previous embodiments, there is a differential (e.g., a pressure differential or voltage differential, such as an electrophoretic voltage potential, or a gravitational field) between the cross-flow buffer input and output ports that causes the cross-flow fluid that enters channel 2010 to flow first through filter 2008 , then through the separation chamber, then through filter 2012 , and finally out of channel via the exit port. There is also a force (e.g., pressure, electric, gravity) that causes fluid entering channel 2010 to flow from end 2006 to end 2014 . As with previous embodiments, as the cross-flow buffer flows across separation chamber, the cross-flow buffer together with filters 2008 and 2012 facilitate the separation of the intact nuclei from the other components of the mixture that flows into channel 2010 from, for example, the cell lysis region 1706 .
Referring back to FIG. 17 , as described above, system 102 may include a concentrator 1712 , as further illustrated in FIG. 22 . As shown in FIG. 22 , a concentrator 1712 , in accordance with one exemplary embodiment, includes a generally triangular shaped channel 2208 (i.e., a channel wherein the width of the channel increases as one moves from an input end to an output end). At the input end of channel 2208 there is an inlet 2202 providing a means for a fluid (e.g., the purified sample collected in cross flow filtration region 1708 , which also contain some waste components from the blood sample and lysis buffer) to enter into channel 2208 . At the opposite end of channel 2208 (i.e., at the output end) there are two waste outlets ( 2204 a and 2204 b ), each of which provides a means for additional waste to exit channel 2208 , and a sample outlet 2206 that provides a means for the desired concentrated fluid to exit channel 2208 . As further shown in FIG. 22 , two filters ( 2210 a and 2210 b ) are disposed in channel 2208 and together form a separation chamber 2212 in channel 2208 . Separation chamber 2212 includes an fluid entry point 2214 that is positioned downstream from inlet 2202 and a fluid exit point 2216 that is adjacent the output end of channel 2208 and that is in fluid communication with outlet 2206 , but not in fluid communication with any of the waste outlets 2204 .
Referring back to FIG. 17 , it can be seen that after the intact nuclei exit filtration region 1708 , the intact nuclei, as well as any waste matter not removed by filtration region 1708 , will flow into the channel 2208 of concentrator 1712 . Referring back now to FIG. 22 , when the intact nuclei and any waste material enter channel 2208 , the mixture will be forced to flow into separation chamber 2212 by, for example, a pressure differential (or other force) between the input end and the output end of channel 2208 . When the mixture is in chamber 2212 , some of the mixture will flow through filter 2210 a towards waste outlet 2204 a , some will flow through filter 2210 b towards waste outlet 2204 b , and the rest will flow the entire length of chamber 2212 and into channel 2223 and eventually to outlet 2206 . For example, the pressure in chamber 2212 may be higher than the pressure at outlets 2204 a , 2204 b and 2206 , thereby forcing some of the mixture to flow to the outlets. Advantageously, the filters 2210 are configured such that the intact nuclei in the mixture are not able to pass through or enter the filter, but any waste material is able to flow through the filter. Accordingly, the mixture that leaves chamber 2212 will have a higher concentration of intact nuclei than the mixture that entered chamber 2212 .
As illustrated in FIG. 17 , outlet 2206 of concentrator 1712 is in fluid communication with an inlet of an interface channel of interface region 1714 . Accordingly, in some embodiments, as described above, a mixture containing a concentrated amount of intact nuclei may flow into the interface channels of interface region 1714 for further testing and analysis.
The interface region 1714 in accordance with one embodiment is further illustrated in FIG. 23 . As shown in FIG. 23 , interface region 1714 may contain a number of microfluidic channels 2304 , such as, for example, 8 microfluidic channels. In some embodiments, the intact nuclei that exit concentrator 1712 are forced to flow through channels 2304 as is know in the art. As is also known in the art, as the intact nuclei flow, DNA from the intact nuclei may be released by lysing the nuclei. The DNA released from the intact nuclei may be amplified as they traverse channels 2304 using, for example, a PCR technique. In such an embodiment, a temperature control system 2306 controls the temperature of the DNA flowing though channels 2304 to create the PCR reaction. Thus, a portion of channels 2304 may be considered an amplification region. A camera 2302 may be positioned relative to channels 2304 to record fluorescent emissions from channels 2304 and thereby detect amplification of the DNA. Systems and methods for amplifying DNA and detecting the amplification of the DNA are described in the above-referenced patents.
In some embodiments, a concentrator is not used and the purified intact nuclei from the cross flow filtration region 1708 are caused to flow directly into the interface region 1714 .
Referring now to FIG. 24 , a flow chart is provided which illustrates a process 2400 according to an embodiment of the invention for using the system shown in FIG. 17 . Process 2400 may begin in step 2402 , wherein fluid from well 1702 (e.g., a blood sample) and a lysis buffer from well 1704 are mixed. That is, the blood sample and lysis buff are forced to flow out of wells 1702 and 1704 , respectively, and into channel 1706 , where the sample and lysis buffer mix. In some embodiments the fluids may be forced out of wells 1702 and 1704 by creating a pressure differential or an electrophoretic voltage.
In step 2404 , while the mixture is flowing along channel 1706 , the lysis buffer selectively lyses, in cell lysing region 1706 , the cellular membranes of the cells in the sample without lysing the nuclear membranes of the cells to produce intact nuclei from the cells.
In step 2406 , the intact nuclei is separated from the sample in a cross-flow filtration region 1708 , which includes one or more cross-flow filters 1710 that has a pore size such that the intact nuclei are not permitted do not pass through the filter and the other components of the patient sample pass through the filter and are carried away by a cross-flow buffer that is controlled to flow through the cross-flow filtration region. In some embodiments, the cross-flow buffer is driven through the cross-flow filtration region by a pressure differential or by an electrophoretic voltage. In step 2408 , which is optional, the intact nuclei are concentrated by concentrator 1712 . In step 2410 , the concentrated nuclei are forced to flow through an interface channel 1714 for downstream analysis.
In some embodiments, the cross-flow region may have multiple filters to filter out not only intact nuclei from the sample, but also bacteria and viruses. For example, the cross-flow filtration region may have three filters, one for separating nuclei from the sample, one for separation bacteria from the sample, and one for separating viruses from the sample, as described above in connection with FIG. 19 . In other embodiments, the cross-flow filter 1710 is configured such that the purified sample from output end 1834 is recirculated back into the input end 1832 for additional passes through separation chamber 1814 for further purification. In one embodiment, this recirculation is accomplished by providing a channel connecting output end 1834 with input end 1832 to permit fluid flow there between, and controllably driving fluid from the output end into the input end by, for example, pressure differential.
Referring now to FIG. 25 , a flow chart is provided illustrating a process 2500 of determining the presence or absence of a nucleic acid in a patient sample according to an embodiment of the invention. Process 2500 may begin in step 2502 , where a patient sample containing cells is mixed with a lysis buffer in a mixing region of a microfluidic device (e.g., region 1706 ), wherein the lysis buffer selectively lyses cellular membranes without lysing nuclear membranes. Next, in step 2504 , the lysis buffer selectively lysis in the mixing region 1706 (a.k.a., “cell lysing region”) the cellular membranes of the cells in the patient sample without lysing the nuclear membranes of the cells to produce intact nuclei from the cells. In step 2506 , the intact nuclei are separated from the patient sample in cross-flow filtration region 1708 as described above. In step 2508 , the nuclei are lysed to release nucleic acid. In step 2510 , the nucleic acid is amplified (e.g., amplified using PCR). In step 2512 , the presence or absence of an amplified product is determined, wherein the presence of the amplified product indicates the presence of the nucleic acid in the patient sample. In some embodiments, the patient sample is first enriched for white blood cells prior to the selective lysis of the cellular membranes. In some embodiments, steps 2502 - 2508 are performed one microfluidic device and steps 2510 - 2512 are performed in a different microfluidic device. In other embodiments, steps 2502 - 2506 are performed one microfluidic device and steps 2508 - 2512 are performed in a different microfluidic device.
Referring now to FIG. 26 , subsystem 102 is illustrated in according with another embodiment. As shown in FIG. 26 , the sample preparation subsystem 102 includes a sample card 2600 that has one or more chambers 2601 that are configured to hold one or more patient samples. Each of the one or more chambers 2601 comprises an inlet 2602 , a filter 2603 , and an outlet 2604 . The sample card 2600 is removably insertable into the sample preparation subsystem 102 , which allows the sample card 2600 to be loaded with the one or more patient samples, and then inserted into the sample preparation subsystem 102 . Each inlet 2602 further comprises one or more channels which may or may not be in fluid communication with each other. FIG. 27 further illustrates one embodiment of the sample card 2600 containing one or more chambers 2601 . As shown in FIG. 27 , each chamber 2601 comprises an inlet 2602 , a filter 2603 , and an outlet 2604 . The filter pore size may be between 1 to 15 um, and preferably is approximately 5 um.
As shown in FIG. 26 , the sample preparation subsystem 102 includes a flow control system 2605 that controls the flow of a lysis buffer from a lysis buffer storage device 2606 into each chamber 2601 of the sample card 2600 through inlets 2602 . The lysis buffer contained in the lysis buffer storage device 2606 selectively lyses cellular membranes to release nuclei and cell debris. The flow control system 2605 then causes the cell debris and lysis buffer to flow through the filter 2603 , through outlets 2604 , and into a removably insertable waste receptacle 2607 , while leaving the nuclei trapped on the filter 2603 . The waste receptacle 2607 is positionable beneath the outlets 2604 to receive the cell debris and lysis buffer from the chambers 2601 . The lysis buffer does not lyse the nuclei from the patient sample. The flow control system 2605 also controls the flow of an elution buffer from an elution buffer storage device 2608 into each chamber 2601 of the sample card 2600 through the inlet 2602 .
As shown in FIG. 26 , the sample preparation subsystem 102 includes a temperature control system 2609 that controls the temperature of the sample card 2600 . The temperature control system 2609 heats the sample card 2600 , which causes the nuclei trapped on the filter 2603 to lyse, thereby releasing the DNA of the nuclei. In this embodiment, the temperature control system uses a sensor 2610 and a heat source 2611 to controllably and effectively heat the sample card to lyse the intact nuclei.
FIG. 26 further illustrates an interface chip 2612 which is removably insertable into the sample preparation subsystem 102 . The interface chip 2612 is positionable beneath the sample card 2600 and is configured to receive the DNA released from the lysed nuclei trapped on the filter 2603 . As shown in FIG. 26 , the interface chip 2612 comprises one or more DNA sample wells 2613 which are in fluid communication with one or more DNA sample outlets 2614 . When inserted into the subsystem 102 , the DNA sample wells 2613 are each aligned with an outlet 2604 from the sample card 2600 , which enables each DNA sample well 2613 to collect the DNA released by the lysed nuclei as the DNA exit the sample card 2600 through the outlet 2604 .
In this embodiment, the main controller 101 communicates with the temperature control system 2609 and the flow control system 2605 . As those skilled in the art will recognize, many options exist for a main controller 101 , such as, for example, a general purpose computer or a special purpose computer. Other specialized control equipment known in the art could also serve the purpose of the main controller 101 .
Referring to FIG. 28 , a sample card 2600 is illustrated with multiple chambers 2601 connected by fluidic channels 2800 . In this embodiment, connecting chambers 2601 using a fluidic channel 2800 allows different numbers of samples to be tested in varying volumes. For example, in the embodiment shown where all chambers 2601 are in fluidic communication via fluidic channels 2800 , the sample card 2600 would allow one patient sample to be tested in a larger volume because every chamber 2601 , being in fluidic communication, would contain the same sample. Alternatively, if none of the chambers 2601 were in fluidic communication, as shown in FIG. 27 , the sample card 2600 would allow testing of multiple patient samples simultaneously, in which each sample could be from the same patient or different patients. When none of the chambers 2601 are in fluidic communication, the number of patient samples to be tested would be limited by the number of chambers 2601 on the sample card 2600 .
While FIG. 28 shows all chambers 2601 being connected, other arrangements are contemplated. The number of chambers 2601 connected together on a sample card 2600 could be many different combinations, which would allow for testing of a desired number of patient samples and a desired volume of each patient sample. For example, a sample card A 200 could be configured to connect the chambers 2601 in pairs via fluidic channels 2800 , which would reduce the number of different patient samples by half, while doubling the volume of each patient sample to be tested. The sample card 2600 can be made from various materials which might depend on the testing requirements of each application; the sample card 2600 can be reusable or disposable to reflect the requirements of each testing application.
FIG. 29 further illustrates the flow control system 2605 according to one embodiment. As shown in FIG. 29 , the flow control system 2605 is controlled by the main controller 101 and comprises a pump 2900 , a pressure control system 2901 , a solution delivery chip 2902 , and a pressure control chip 2903 . The pressure control system 2901 comprises an air source and a pressure sensor which allows the flow control system 2605 to control the delivery of the elution buffer and the lysis buffer to the sample card 2600 using pressure to move the solutions. The solution delivery chip 2902 comprises multiple channels for delivering lysis buffer and elution buffer to each chamber 2601 of the sample card 2600 . The pressure control chip 2903 comprises multiple channels for providing pressure to each chamber 2601 of the sample card 2600 . While this embodiment illustrates the use of a solution delivery chip 2902 , a pump 2900 , and a pressure control system 2901 in the flow control system 2605 , the different components can be used in different combinations. For example, the pump 2900 and the solution delivery chip 2902 can be used without the pressure control system 2901 . In another embodiment, the pressure control system 2901 can comprise multiple channels for controlling air pressure in each chamber 2601 of the sample card 2600 .
Referring to FIG. 30 , the solution delivery chip 2902 is illustrated according to one embodiment. As shown in FIG. 30 , the solution delivery chip comprises multiple channels 3000 in fluidic communication the chambers 2601 of the sample card. The channels 3000 comprise one or more solution inlets 3001 which receive the buffers from the pump 2900 . The channels 3000 further comprise one or more solution outlets 3002 that are in fluid communication with the inlets 2602 of the sample card 2600 which allows the lysis buffer and the elution buffer to be delivered to the chambers 2601 of the sample card 2600 via the solution outlets 3002 of the solution delivery chip 2902 .
Referring to FIG. 31 , the pressure control chip 2903 is illustrated according to one embodiment. As shown in FIG. 31 , the pressure control chip 2903 comprises multiple pressure channels 3100 , and each pressure channel 3100 is in fluid communication with a pressure inlet 3101 and a pressure outlet 3102 . In this embodiment, each pressure channel is in fluid communication with the same pressure inlet 3101 ; however, other embodiments are contemplated where there may be more than one pressure inlet 3101 . The pressure inlet 3101 is in fluid communication with the pressure control system 2901 in order to deliver pressure to the pressure control chip 2903 . The pressure outlets 3102 are in fluid communication with the inlets 2602 of the sample card 2600 , which allows the pressure control chip 293 to deliver pressure to the chambers 2601 of the sample card 2600 .
FIG. 32 is a flowchart illustrating a method 3200 for isolating DNA cells in a patient sample. While the method 3200 is not limited to the system provided in FIG. 26 , one preferred embodiment of the method can utilize a system similar to that shown in FIG. 26 , and FIG. 26 is used for reference purposes to assist in describing the method. As shown in FIG. 32 , in step 3202 a sample preparation system 102 is provided, wherein the system comprises: (i) a sample card 2600 having multiple chambers 2601 , wherein each chamber 2601 comprises an inlet 2602 , a filter 2603 , and an outlet 2604 , where the sample card 2600 is removably insertable into the sample preparation subsystem 102 ; (ii) a flow control system 2605 for controlling flow of a lysis buffer and an elution buffer to each chamber 2601 of the sample card 2600 ; (iii) a temperature control system 2609 for heating the filter 2603 in the sample card 2600 ; (iv) a removably insertable waste receptacle 2607 which is positionable beneath the sample card 2600 ; and (v) an interface chip 2612 comprising multiple DNA sample wells 2613 and DNA sample outlets 2614 , where the interface chip 2612 is positionable beneath the sample card 2600 .
In step 3204 , the patient sample is loaded into the chambers 2601 of the sample card 2600 . In step 3206 , the sample card 2600 containing the patient sample is inserted into the sample preparation system 102 . In step 3208 , the flow control system 2605 delivers a lysis buffer from the lysis buffer storage device 2606 to the chamber 2601 of the sample card 2600 through the inlet 2602 . The lysis buffer selectively lyses the cellular membranes of the patient sample without lysing the nuclear membranes of the nuclei. The reaction produces a solution comprising a lysis buffer, intact nuclei and cellular debris, in the chamber 2601 of the sample card 2600 . In step 3210 , the removably insertable waste receptacle 2607 is positioned below the sample card 2600 and the flow control system 2605 operates to drive the solution through the filter 2603 of the chamber 2601 . The filter 2603 traps the intact nuclei from the solution while the lysis buffer and the cellular debris are driven out of the chamber 2601 through the outlet 2604 by the flow control system 2605 . The lysis buffer and cellular debris are collected when exiting the chamber 2601 through the outlet 2604 in the waste receptacle 2607 .
In step 3212 , the temperature control system 2609 operates to heat the filter 2603 , which heats the intact nuclei trapped in the filter 2603 . The heating of the intact nuclei causes the nuclei to lyse, which releases DNA from the nuclei. In step 3214 , the flow control system 2605 operates to deliver the elution buffer from the elution buffer storage device 2608 to the chamber 2601 of the sample card 2600 through the inlet 2602 . In step 3216 , the interface card 2612 is positioned beneath the sample card 2600 , and the flow control system 2605 operates to drive the elution buffer and the DNA through the outlet 2604 of the chamber 2601 while leaving the lysed nuclei on the filter 2603 . The elution buffer and DNA are deposited in the DNA sample well 2613 of the interface chip 2612 after exiting the chamber 2601 though the outlet 2604 . This method thus allows the DNA to be isolated from the patient sample.
An optional step following the DNA isolation described above can be to deliver the lysis buffer from the lysis buffer containment device 2606 into the chambers 2601 of the sample card 2600 using the flow control device 2605 , then drive the solution out of the chamber 2601 through the outlet 2604 by operation of the flow control system 2605 in order to clean the filter 2603 . This optional step can be repeated multiple times to provide the desired level of cleanliness of the filter 2603 .
While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments. Variations of the embodiments described above 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.
Additionally, while the processes described above and illustrated in the drawings are shown as a sequence of steps, this was done solely for the sake of illustration. Accordingly, it is contemplated that some steps may be added, some steps may be omitted, the order of the steps may be re-arranged, and some steps may be performed in parallel. | The present invention relates to methods and systems for microfluidic DNA sample preparation. More specifically, embodiments of the present invention relate to methods and systems for the isolation of DNA from patient samples on a microfluidic device and use of the DNA for downstream processing, such as performing amplification reactions and thermal melt analysis on the microfluidic device. | 2 |
[0001] This application claims priority under 35 U.S.C. § 119 to U.S. Provisional application No. 60/822,240, filed 13 Aug. 2006, the entirety of which is incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to devices, systems, and processes useful as bollards, and more specifically to ground level security bollards.
[0004] 2. Brief Description of the Related Art
[0005] Bollards have been used to provide perimeter security for a secured facility. The bollards may restrict traffic flow and vehicle penetration into the facility grounds.
[0006] FIGS. 1 a and 1 b illustrate a typical security bollard installation system 100 . Typically, current vertical bollards 110 are installed three (3) to four (4) feet deep in the ground 120 . A trench is dug approximately three (3) feet wide and of a length determined based on the perimeter to be protected. The trench is filled with concrete 130 after the vertical bollards 110 are set in the trench. Installing the bollards 110 this deep caused problems with hitting underground utilities (gas, water, telephone, electricity), and underground parking and building structures.
[0007] Therefore, there remains a need for a bollard system that does not require a deep trench, yet is impact resistant and field adjustable.
SUMMARY
[0008] One of numerous aspects of the present invention includes a shallow bollard sub-assembly for securing an area against vehicular penetration comprising a base, an input member secured to the base and extending vertically from the base, wherein the input member is configured and arranged to transfer an impact to the base when a vehicle strikes the input member and at least three leveling legs connected to the base to position the base above a supporting surface, wherein each of the leveling legs is individually adjustable to alter an elevation of a respective portion of the base relative to the supporting surface.
[0009] Another aspect of the present invention includes a shallow bollard system for securing an area against vehicular penetration comprising a plurality of bollard sub-assemblies and a plurality of linking members connecting adjacent ones of the plurality of bollard sub-assemblies, wherein each of the bollard sub-assemblies each includes a base an input member secured to the base and extending vertically from the base, wherein the input member is configured and arranged to transfer an impact to the base when a vehicle strikes the input member, and at least three leveling legs connected to the base to position the base above a supporting surface, wherein each of the leveling legs is individually adjustable to alter an elevation of a respective portion of the base relative to the supporting surface.
[0010] Yet another aspect of the present invention includes a method for securing an area against vehicular penetration comprising providing a plurality of bollard sub-assemblies, each of the bollard sub-assemblies includes a base, an impact member secured to the base and extending vertically from the base, wherein the input member is configured and arranged to transfer an impact to the base when a vehicle strikes the input member, and at least three leveling legs, interconnecting one of the plurality of bollard sub-assemblies to an adjacent one of the bollard sub-assemblies, and adjusting a vertical position of at least a part of at least one of the bollard sub-assemblies relative to a supporting surface by moving appropriate ones of the at least three leveling legs.
[0011] Still other aspects, features, and attendant advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description of embodiments constructed in accordance therewith, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention of the present application will now be described in more detail with reference to exemplary embodiments of the apparatus and method, given only by way of example, and with reference to the accompanying drawings, in which:
[0013] FIGS. 1 a and 1 b illustrate a typical, prior art bollard system;
[0014] FIG. 2 illustrates a side elevational view of an exemplary bollard system embodying principles of the present invention, when installed.
[0015] FIGS. 3 a and 3 b illustrate side elevational and top plan view, respectively, of a bollard system in accordance with the present invention;
[0016] FIG. 4 illustrates an exemplary embodiment of a leveling leg in accordance with the present invention;
[0017] FIG. 5 illustrates views of a bollard system in accordance with the present invention, disassembled; and
[0018] FIG. 6 illustrates views of a bollard system in accordance with the present invention, in an assembled configuration.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0019] Referring to the drawing figures, like reference numerals designate identical or corresponding elements throughout the several figures.
[0020] With reference to FIGS. 2 , 5 , and 6 , an exemplary bollard system of the present invention includes a shallow mounted installation system 10 . The shallow bollard system 10 typically may require a support surface 20 formed as only a nine (9) inch deep trench in the ground, or a recess or a channel formed in a building surface or a bed for a road or a sidewalk. Referring to FIGS. 5 and 6 , the shallow bollard system 10 may include a plurality of shallow bollard sub-assemblies 30 , 30 ′ interconnected to one another by linking members 32 in a manner to be described later.
[0021] Referring to FIGS. 2 , 3 a , and 3 b , each shallow bollard sub-assembly 30 may include a base 34 , a vertical input member (or vertical bollard) 36 , and a plurality of leveling legs 38 . The shallow bollard sub-assembly 30 may be designed to transfer an impact from the input member 36 to the base 34 when a vehicle strikes the input member 36 . The base 34 , the leveling legs 38 , and at least a portion of the impact member 36 may be encased in concrete 40 after the shallow bollard system 10 has been properly assembled, positioned and leveled, as illustrated in FIG. 2 .
[0022] The surface 20 upon which the shallow bollard system 10 may be supported may take the form of a trench or other excavation, a contoured ground surface such as a bed for a road or sidewalk, or a surface of a building structure, and may be sloped, uneven and/or follow a curved path. The leveling legs 38 may be individually adjusted to level and align each shallow bollard sub-assembly 30 and may be adjusted as a group to raise and lower the respective bases 34 of the entire shallow bollard system 10 to the required elevation relative to the support surface 20 in order to accommodate varying contour(s) and path(s) of the support surface 20 . The structure and adjustment of each level leg 38 is described next.
[0023] The shallow bollard sub-assembly 30 may have at least three leveling legs 38 disposed on the base 34 to define a triangular pattern (see, e.g., FIG. 3 b ). This pattern may provide the appropriate degree(s) of freedom of adjustment to obtain a level bollard system 10 with a minimum number of leveling legs 38 . However, more leveling legs 38 and/or other arrangements of the leveling legs 38 relative to the base 34 may be provided.
[0024] As viewed in FIG. 4 , each leveling leg 38 may include a foot member 42 and an adjusting member 44 . The foot member 42 may include a bottom surface 46 that may engage the support surface 20 (not shown, see FIG. 2 ) when the shallow bollard sub-assembly 30 (not shown, see FIG. 2 ) is positioned over the support surface 20 . In a preferred embodiment, the adjusting member 44 may be a bolt 48 having a head 50 at one end of a threaded stud 52 . Preferably, the foot member 42 may be loosely secured to the adjusting member 44 as explained below.
[0025] Still referring to FIG. 4 , the foot member 42 may include a pipe 54 opened at each end. A pad 56 may be secured to and close off one of the opened ends. A washer 58 may be secured to the other opened end of the pipe 54 . Preferably, the outer dimension of the washer 58 may be greater than the inner dimension of the pipe 54 and the inner dimension of the washer 58 may be less than the inner dimension of the pipe 54 and greater than the outer diameter of the threaded stud 52 .
[0026] As illustrated in FIG. 4 , a second washer 60 may be fixed to the end of the threaded stud 52 opposite the head 50 . The outer dimension of the second washer 60 may be less than the inner dimension of the pipe 54 and greater than the inner dimension of the washer 58 . Thus, the second washer 60 may be captured between the washer 58 and the pad 56 , thereby loosely securing the foot member 42 to the adjusting member 44 . Alternatively, the foot member 44 may be rigidly fixed to the bolt 48 . Optionally, yet not necessary, provisions can be added to reduce the friction between the pad 56 and the washer 60 , to permit easier rotation of the stud 52 . By way of non-limiting example, a number of ball bearings 92 can be located in the space between the pad 56 and the washer 60 , which are free to roll. Other provisions, such as liquid, paste, or solid lubricants, or the like, can also be used to reduce the rotating friction between the pad 56 and the washer 60 .
[0027] Prior to securing the foot member 42 to the bolt 48 , a nut 62 may be threaded onto the threaded stud 52 . See FIG. 4 . Preferably, the nut 62 may be rigidly fixed to the base 34 (not shown, see FIGS. 3 a and 3 b ) by a weld between the nut 62 and a respective connecting member 64 of the base 34 . See FIGS. 3 a and 3 b . In order to adjust the elevation of the base 34 , the bolt 48 may be rotated clockwise or counter-clockwise relative to the nut 62 , thereby raising or lowering the foot member 42 relative to the base 34 . Alternatively, the base 34 may be provided with a through bore that may directly engage the threaded stud 52 .
[0028] Other arrangements of the adjusting member and the foot portion may be possible, in so far as the adjusting member is non-movably secured to one of the foot member and the base and movably engaged with the other of the foot member and the base. For example, a threaded stud may be rigidly fixed to the base and extend from the base and the foot member may have a threaded portion, such as a nut welded thereto, such that rotation of the foot member relative to the stud raises or lowers the position of the foot member relative to the base. Alternatively, the adjusting member may be a fluid powered piston/cylinder arrangement, a gear assembly such as rack and pinion arrangement, a ratchet-type assembly, etc.
[0029] Referring to FIGS. 3 a and 3 b , the base 34 may include two horizontal members 66 and two connecting members 64 . The horizontal members 66 extend in a longitudinal direction L (see FIG. 3 b ) and the connecting members 64 may extend perpendicular to the longitudinal direction L (see FIG. 3 b ), or optionally can form angles with the horizontal members other than 90 degrees. The horizontal members 66 may be connected to one another by the connecting members 64 . The connecting members 64 may be secured to the ends of the horizontal members 66 by any conventional means, such as bolts, rivets, or welds. Preferably, the connecting members 64 may be welded to the horizontal members 66 . The connecting members 64 may be provided to spread the impact load from the input member 36 to the concrete 40 subsequent to a vehicle striking the input member 36 . See also FIG. 2 .
[0030] In the preferred embodiment of FIGS. 3 a and 3 b , the horizontal members 66 may be I-beams and the connecting members 64 may be angle irons. Alternatively, the base 34 may be formed of a single metal sheet, cast as frame, machined from a single piece of metal, etc.
[0031] Referring to FIG. 3 a , preferably, the input member 36 may include a hollow pipe 68 that may receive concrete 40 therein after the bollard sub-assembly 30 has been properly positioned and leveled on the support surface 20 (see also FIG. 2 ). In order to secure the input member 36 to the base 34 , the hollow pipe 68 may be inserted into holes in upper and lower square plates 70 , 72 . The square plates 70 , 72 may be welded (at 74 ) to the top and bottom of the horizontal members 66 .
[0032] Preferably as shown in FIG. 3 b , the square plates 70 , 72 are oriented relative to the horizontal members 66 such that a line extending between a pair of diagonally opposed corners 74 , 76 of each square plate 70 , 72 extends parallel to the longitudinal direction L of the horizontal members 66 . This preferred orientation locates the edges 78 of the square plates 70 , 72 at a preferred angle of 45° relative to the longitudinal direction L of the horizontal members 66 . Of course, other angular orientations of the plates 70 , 72 to each other and to the horizontal members 66 can also be used.
[0033] After the shallow bollard system 10 is properly leveled and encased in concrete 40 , this preferred orientation may allow maximum contact of the square plates 70 , 72 to the concrete 40 at impact caused by a vehicle striking the input member 36 . At the time of impact on the input member 36 by a vehicle, with the system preferably, although not necessarily, oriented so that the vehicle impacts the system from the left in the drawing figures, the energy from the concrete-filled hollow pipe 68 may be transferred through the square plates 70 , 72 to the horizontal members 66 and into the concrete 40 . The concrete 40 may be relied upon to provide mass since, at impact by a vehicle, the bollard sub-assemblies 30 may try to rotate and/or translate relative to the support surface 20 .
[0034] FIG. 3 b , by way of example, also illustrates stiffener plates 80 , 82 , 84 , 86 that may extend vertically between and connect to the upper and lower square plates 70 , 72 . During impact by a vehicle, the input member 36 may rotate back. The stiffener plates 80 , 82 , 84 , 86 may help transfer energy from the upper square plate 70 to the lower square plate 72 (see also FIG. 3 a ) and the horizontal members 66 and the concrete 40 such that this backward rotation may be prevented or at least minimized. The stiffener plates 80 , 82 , 84 , 86 are not illustrated in the other drawing figures so as to not otherwise obscure aspects of the invention.
[0035] The bollard sub-assembly 30 may be connected to an adjacent bollard sub-assembly 30 ′ by linking members 32 . See FIGS. 5 and 6 . The linking members 32 may be connected to the bollard sub-assemblies 30 by bolts 88 , or by other devices such as rivets, welds, and the like. As shown in FIG. 5 , a single linking member 32 may be used to connect the two shallow bollard sub-assemblies 30 , 30 ′. However, any number of linking members 32 may be used to connect the adjacent bollard sub-assemblies 30 .
[0036] As illustrated by way of example in FIG. 5 , bolt holes 90 in each linking member 32 may be slotted in a direction perpendicular to the longitudinal direction L (see FIG. 3 b ) of the horizontal members 66 and each base 34 may include bolt holes 90 that may be slotted in the longitudinal direction L of the horizontal members 66 . This orientation of the bolt holes 90 may provide for adjustment for a curved path intended for the bollard system 10 and/or an uneven or sloping support surface 20 .
[0037] The linking members 32 may also be useful to provide proper spacing between two adjacent bollard sub-assemblies 30 . The bollard sub-assemblies 30 may be, according to an advantageous embodiment, spaced a minimum of 32″ (for handicapped access) and maximum of 34″, for impact and structural requirements, although other spacings between adjacent bollard sub-assemblies 30 are also part of this invention.
[0038] Preferably, the linking member 32 may be formed from angle iron for structural strength. See FIG. 5 . While the linking member 32 may be formed of a different material and/or shape, preferably it is formed of the same material (e.g., steel) as the angle iron of the connecting members 64 of the base 34 .
[0039] The linking member 32 may help keep the bollard system 10 from moving by transferring the impact load from a vehicle on the input member 36 to an adjacent bollard sub-assembly 30 and throughout the concrete 40 .
[0040] While the invention has been described in detail with reference to exemplary embodiments thereof, it will be apparent to one skilled in the art that various changes can be made, and equivalents employed, without departing from the scope of the invention. The foregoing description of the preferred embodiments 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 modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiments were chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and their equivalents. | A bollard system includes leveling legs for each section of the system, support plates rotated to distribute force to supporting beams, and connecting angles to join together adjacent sub-assemblies within a single installation. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to catalytic hydrocarbon conversion, and more specifically to the use of a catalyst system comprising MTW-type zeolite substantially free of mordenite in a hydrocarbon conversion process, and even more specifically to an aromatics isomerization process to convert ethylbenzene into xylene with a bimetallic catalyst that preferably contains platinum and tin.
BACKGROUND OF THE INVENTION
[0002] The xylenes, para-xylene, meta-xylene and ortho-xylene, are important intermediates that find wide and varied application in chemical syntheses. Para-xylene upon oxidation yields terephthalic acid that is used in the manufacture of synthetic textile fibers and resins. Meta-xylene is used in the manufacture of plasticizers, azo dyes, wood preservers, etc. Ortho-xylene is feedstock for phthalic anhydride production.
[0003] Xylene isomers from catalytic reforming or other sources generally do not match demand proportions as chemical intermediates, and further comprise ethylbenzene, which is difficult to separate or to convert. Para-xylene in particular is a major chemical intermediate with rapidly growing demand, but amounts to only 20-25% of a typical C 8 aromatics stream. Adjustment of isomer ratio to demand can be effected by combining xylene-isomer recovery, such as adsorption for para-xylene recovery, with isomerization to yield an additional quantity of the desired isomer. Isomerization converts a non-equilibrium mixture of the xylene isomers that is lean in the desired xylene isomer to a mixture approaching equilibrium concentrations.
[0004] Various catalysts and processes have been developed to effect xylene isomerization. In selecting appropriate technology, it is desirable to run the isomerization process as close to equilibrium as practical in order to maximize the para-xylene yield; however, associated with this is a greater cyclic C 8 loss due to side reactions. The approach to equilibrium that is used is an optimized compromise between high C 8 cyclic loss at high conversion (i.e., very close approach to equilibrium) and high utility costs due to the large recycle rate of unconverted C 8 aromatics. Catalysts thus are evaluated on the basis of a favorable balance of activity, selectivity and stability.
[0005] U.S. Pat. No. 4,899,012 discloses an alkylaromatic isomerization process based on a bimetallic pentasil-type zeolitic catalyst system that also produces benzene. U.S. Pat. No. 4,962,258 discloses a process for liquid phase xylene isomerization over gallium-containing, crystalline silicate molecular sieves as an improvement over aluminosilicate zeolites ZSM-5, ZSM-12 (MTW-type), and ZSM-21 as shown in U.S. Pat. No. 3,856,871. The '258 patent refers to borosilicate work, as exemplified in U.S. Pat. No. 4,268,420, and to zeolites of the large pore type such as faujasite or mordenite.
[0006] U.S. Pat. No. 5,744,673 discloses an isomerization process using beta zeolite and exemplifies the use of gas-phase conditions with hydrogen. U.S. Pat. No. 5,898,090 discloses an isomerization process using crystalline silicoaluminophosphate molecular sieves. U.S. Pat. No. 6,465,705 discloses a mordenite catalyst for isomerization of aromatics that is modified by an IUPAC Group III element.
[0007] Catalysts for isomerization of C 8 aromatics ordinarily are classified by the manner of processing ethylbenzene associated with the xylene isomers. Ethylbenzene is not easily isomerized to xylenes, but it normally is converted in the isomerization unit because separation from the xylenes by superfractionation or adsorption is very expensive. A widely used approach is to dealkylate ethylbenzene to form principally benzene while isomerizing xylenes to a near-equilibrium mixture. An alternative approach is to react the ethylbenzene to form a xylene mixture via conversion to and reconversion from naphthenes in the presence of a solid acid catalyst with a hydrogenation-dehydrogenation function. The former approach commonly results in higher ethylbenzene conversion, thus lowering the quantity of recycle to the para-xylene recovery unit and concomitant processing costs, but the latter approach enhances xylene yield by forming xylenes from ethylbenzene. A catalyst composite and process which enhance conversion according to the latter approach, i.e., achieve ethylbenzene isomerization to xylenes with high conversion, would effect significant improvements in xylene-production economics.
SUMMARY OF THE INVENTION
[0008] A principal object of the present invention is thus to provide a process for the isomerization of alkylaromatic hydrocarbons. More specifically, the process of the present invention is directed to liquid phase isomerization for C 8 aromatic hydrocarbons over a MTW-type zeolite catalyst in order to obtain improved yields of desired xylene isomers.
[0009] The present invention is based on the discovery that a catalyst system comprising platinum and tin on a substantially mordenite-free MTW-type zeolite with a binder demonstrates improved conversion and selectivity in C 8 aromatics isomerization, while minimizing undesired benzene formation.
[0010] Accordingly, a broad embodiment of the present invention is directed toward a process for the isomerization of alkylaromatics comprising contacting a C 8 aromatics rich hydrocarbon feed stream comprising ethylbenzene and less than the equilibrium amount of xylenes with catalyst having MTW zeolite and a platinum-group element and a Group IVA element (IUPAC 14) of the Periodic Table [See Cotton and Wilkinson, Advanced Inorganic Chemistry, John Wiley & Sons (Fifth Edition, 1988)], which is preferably tin. Preferably the catalyst comprises substantially mordenite-free MTW zeolite, preferably with silica to alumina ratio less than about 45, at isomerization conditions to obtain a product having increased xylenes content relative to that of the feedstock.
[0011] These, as well as other objects and embodiments will become evident from the following detailed description of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0012] The feedstocks to the aromatics isomerization process of this invention comprise isomerizable alkylaromatic hydrocarbons of the general formula C 6 H( 6-n )R n , where n is an integer from 2 to 5 and R is CH 3 , C 2 H 5 , C 3 H 7 , or C 4 H 9 , in any combination and including all the isomers thereof. Suitable alkylaromatic hydrocarbons include, for example but without so limiting the invention, ortho-xylene, meta-xylene, para-xylene, ethylbenzene, ethyltoluenes, tri-methylbenzenes, di ethylbenzenes, tri-ethyl-benzenes, methylpropylbenzenes, ethylpropylbenzenes, di-isopropylbenzenes, and mixtures thereof.
[0013] A particularly preferred application of the catalyst system of the present invention is the isomerization of a C 8 aromatic mixture containing ethylbenzene and xylenes. Generally the mixture will have an ethylbenzene content of about 1 to about 50 wt-%, an ortho-xylene content of 0 to about 35 wt-%, a meta-xylene content of about 20 to about 95 wt-% and a para-xylene content of 0 to about 30 wt-%. The aforementioned C 8 aromatics are a non-equilibrium mixture, i.e., at least one C 8 aromatic isomer is present in a concentration that differs substantially from the equilibrium concentration at isomerization conditions. Usually the non-equilibrium mixture is prepared by removal of para-, ortho- and/or meta-xylene from a fresh C 8 aromatic mixture obtained from an aromatics-production process.
[0014] The alkylaromatic hydrocarbons may be utilized in the present invention as found in appropriate fractions from various refinery petroleum streams, e.g., as individual components or as certain boiling-range fractions obtained by the selective fractionation and distillation of catalytically cracked or reformed hydrocarbons. Concentration of the isomerizable aromatic hydrocarbons is optional; the process of the present invention allows the isomerization of alkylaromatic-containing streams such as catalytic reformate with or without subsequent aromatics extraction to produce specified xylene isomers and particularly to produce para-xylene. A C 8 aromatics feed to the present process may contain nonaromatic hydrocarbons, i.e., naphthenes and paraffins, in an amount up to about 30 wt-%. Preferably the isomerizable hydrocarbons consist essentially of aromatics, to ensure pure products from downstream recovery processes. Moreover, a C 8 aromatics feed that is rich in undesired ethylbenzene can be supplied such that it can be converted to xylenes or other non-C 8 compounds in order to further concentrate desired xylene species.
[0015] According to the process of the present invention, an alkylaromatic hydrocarbon feed mixture, preferably in admixture with hydrogen, is contacted with a catalyst of the type hereinafter described in an alkylaromatic hydrocarbon isomerization zone. Contacting may be effected using the catalyst in a fixed-bed system, a moving-bed system, a fluidized-bed system, or in a batch-type operation. In view of the danger of attrition loss of the valuable catalyst and of the simpler operation, it is preferred to use a fixed-bed system. In this system, a hydrogen-rich gas and the feed mixture are preheated by suitable heating means to the desired reaction temperature and then passed into an isomerization zone containing a fixed bed of catalyst. The conversion zone may be one or more separate reactors with suitable means therebetween to ensure that the desired isomerization temperature is maintained at the entrance to each zone. The reactants may be contacted with the catalyst bed in either upward-, downward-, or radial-flow fashion, and the reactants may be in the liquid phase, a mixed liquid-vapor phase, or a vapor phase when contacted with the catalyst.
[0016] The alkylaromatic feed mixture, preferably a non-equilibrium mixture of C 8 aromatics, is contacted with the isomerization catalyst at suitable alkylaromatic-isomerization conditions. Such conditions comprise a temperature ranging from about 0° to 600° C. or more, and preferably in the range of from about 300° to 500° C. The pressure generally is from about 1 to 100 atmospheres absolute, preferably less than about 50 atmospheres. Sufficient catalyst is contained in the isomerization zone to provide a liquid hourly space velocity with respect to the hydrocarbon feed mixture of from about 0.1 to 30 h −1 , and preferably 0.5 to 10 hr −1 . The hydrocarbon feed mixture optimally is reacted in admixture with hydrogen at a hydrogen/hydrocarbon mole ratio of about 0.5:1 to about 25:1 or more. Other inert diluents such as nitrogen, argon and light hydrocarbons may be present.
[0017] The reaction proceeds via the mechanism, described hereinabove, of isomerizing xylenes while reacting ethylbenzene to form a xylene mixture via conversion to and reconversion from naphthenes. The yield of xylenes in the product thus is enhanced by forming xylenes from ethylbenzene. The loss of C 8 aromatics through the reaction thus is low: typically less than about 4 wt-% per pass of C 8 aromatics in the feed to the reactor, preferably no more than about 3.5 wt-%, and most preferably less than 3 wt-%.
[0018] The particular scheme employed to recover an isomerized product from the effluent of the reactors of the isomerization zone is not deemed to be critical to the instant invention, and any effective recovery scheme known in the art may be used. Typically, the liquid product is fractionated to remove light and/or heavy byproducts to obtain the isomerized product. Heavy byproducts include A 10 compounds such as dimethylethylbenzene. In some instances, certain product species such as ortho xylene or dimethylethylbenzene may be recovered from the isomerized product by selective fractionation. The product from isomerization of C 8 aromatics usually is processed to selectively recover the para-xylene isomer, optionally by crystallization. Selective adsorption is preferred using crystalline aluminosilicates according to U.S. Pat. No. 3,201,491. Improvements and alternatives within the preferred adsorption recovery process are described in U.S. Pat. No. 3,626,020, U.S. Pat. No. 3,696,107, U.S. Pat. No. 4,039,599, U.S. Pat. No. 4,184,943, U.S. Pat. No. 4,381,419 and U.S. Pat. No. 4,402,832, incorporated herein by reference.
[0019] An essential component of the catalyst of the present invention is at least one MTW type zeolitic molecular sieve, also characterized as “low silica ZSM-12” and defined in the instant invention to include molecular sieves with a silica to alumina ratio less than about 45, preferably from about 20 to about 40. Preferably, the MTW type zeolite is substantially mordenite-free, which is herein defined to mean a MTW component containing less than about 20 wt-% mordenite impurity, preferably less than about 10 wt-%, and most preferably less than about 5 wt-% mordenite which is about at the lower level of detect-ability using most characterization methods known to those skilled in the art such as x-ray diffraction crystallography. Applicants have surprisingly discovered that a unique and novel property of MTW-type zeolite appears when the silica to alumina ratio is lowered, and that the avoidance of the concomitant mordenite phase under low silica conditions results in a catalyst composite with excellent properties for low aromatic ring loss when converting ethylbenzene to para-xylene under minimum benzene conditions.
[0020] The preparation of MTW-type zeolites by crystallizing a mixture comprising an alumina source, a silica source and templating agent uses methods well known in the art. U.S. Pat. No. 3,832,449 more particularly describes an MTW-type zeolite using tetraalkylammonium cations. U.S. Pat. No. 4,452,769 and U.S. Pat. No. 4,537,758 use a methyltriethylammonium cation to prepare a highly siliceous MTW-type zeolite. U.S. Pat. No. 6,652,832 uses a N,N-dimethylhexamethyleneimine cation as a template to produce low silica-to-alumina ratio MTW type zeolite without MFI impurities. Preferably high purity crystals are used as seeds for subsequent batches.
[0021] The MTW-type zeolite is preferably composited with a binder for convenient formation of catalyst particles. The proportion of zeolite in the catalyst is about 1 to 90 wt-% , preferably about 2 to 20 wt-%, the remainder other than metal and other components discussed herein being the binder component.
[0022] As mentioned previously, the zeolite will usually be used in combination with a refractory inorganic oxide binder. The binder should be a porous, adsorptive support having a surface area of about 25 to about 500 m 2 /g. It is intended to include within the scope of the present invention binder materials which have traditionally been utilized in hydrocarbon conversion catalysts such as: (1) refractory inorganic oxides such as alumina, titania, zirconia, chromia, zinc oxide, magnesia, thoria, boria, silica-alumina, silica-magnesia, chromia-alumina, alumina-boria, silica-zirconia, phosphorus-alumina, etc.; (2) ceramics, porcelain, bauxite; (3) silica or silica gel, silicon carbide, clays and silicates including those synthetically prepared and naturally occurring, which may or may not be acid treated, for example, attapulgite clay, diatomaceous earth, fuller's earth, kaolin, kieselguhr, etc.; (4) crystalline zeolitic aluminosilicates, either naturally occurring or synthetically prepared such as FAU, MEL, MFI, MOR, MTW (IUPAC Commission on Zeolite Nomenclature), in hydrogen form or in a form which has been exchanged with metal cations, (5) spinels such as MgAl 2 O 4 , FeAl 2 O 4 , ZnAl 2 O 4 , CaAl 2 O 4 , and other like compounds having the formula MO Al 2 O 3 where M is a metal having a valence of 2; and (6) combinations of materials from one or more of these groups.
[0023] A preferred refractory inorganic oxide for use in the present invention is alumina. Suitable alumina materials are the crystalline aluminas known as the gamma-, eta-, and theta-alumina, with gamma- or eta-alumina giving the best results.
[0024] A shape for the catalyst composite is an extrudate. The well-known extrusion method initially involves mixing of the molecular sieve with optionally the binder and a suitable peptizing agent to form a homogeneous dough or thick paste having the correct moisture content to allow for the formation of extrudates with acceptable integrity to withstand direct calcination. Extrudability is determined from an analysis of the moisture content of the dough, with a moisture content in the range of from about 30 to about 50 wt-% being preferred. The dough is then extruded through a die pierced with multiple holes and the spaghetti-shaped extrudate is cut to form particles in accordance with techniques well known in the art. A multitude of different extrudate shapes is possible, including, but not limited to, cylinders, cloverleaf, dumbbell and symmetrical and asymmetrical polylobates. It is also within the scope of this invention that the extrudates may be further shaped to any desired form, such as spheres, by marumerization or any other means known in the art.
[0025] An alternative shape of the composite is a sphere continuously manufactured by the well-known oil drop method. Preparation of alumina-bound spheres generally involves dropping a mixture of molecular sieve, alumina sol, and gelling agent into an oil bath maintained at elevated temperatures. Alternatively, gelation of a silica hydrosol may be effected using the oil-drop method. One method of gelling this mixture involves combining a gelling agent with the mixture and then dispersing the resultant combined mixture into an oil bath or tower which has been heated to elevated temperatures such that gelation occurs with the formation of spheroidal particles. The gelling agents that may be used in this process are hexamethylene tetraamine, urea or mixtures thereof. The gelling agents release ammonia at the elevated temperatures which sets or converts the hydrosol spheres into hydrogel spheres. The spheres are then continuously withdrawn from the oil bath and typically subjected to specific aging treatments in oil and an ammoniacal solution to further improve their physical characteristics.
[0026] Preferably the resulting composites are then washed and dried at a relatively low temperature of about 50-200° C. and subjected to a calcination procedure at a temperature of about 450-700° C. for a period of about 1 to about 20 hours.
[0027] Catalysts of the invention also comprise a platinum-group metal, including one or more of platinum, palladium, rhodium, ruthenium, osmium, and iridium. The preferred platinum-group metal is platinum. The platinum-group metal component may exist within the final catalyst composite as a compound such as an oxide, sulfide, halide, oxysulfide, etc., or as an elemental metal or in combination with one or more other ingredients of the catalyst composite. It is believed that the best results are obtained when substantially all the platinum-group metal component exists in a reduced state. This component may be present in the final catalyst composite in any amount which is catalytically effective; the platinum-group metal generally will comprise about 0.01 to about 2 wt-% of the final catalyst, calculated on an elemental basis. Excellent results are obtained when the catalyst contains about 0.05 to about 1 wt-% of platinum.
[0028] The platinum-group metal component may be incorporated into the catalyst composite in any suitable manner. One method of preparing the catalyst involves the utilization of a water-soluble, decomposable compound of a platinum-group metal to impregnate the calcined sievelbinder composite. Alternatively, a platinum-group metal compound may be added at the time of compositing the sieve component and binder. Complexes of platinum group metals which may be employed in impregnating solutions, co-extruded with the sieve and binder, or added by other known methods include chloroplatinic acid, chloropalladic acid, ammonium chloroplatinate, bromoplatinic acid, platinum trichloride, platinum tetrachloride hydrate, platinum dichlorocarbonyl dichloride, tetramine platinic chloride, dinitrodiaminoplatinum, sodium tetranitroplatinate (II), palladium chloride, palladium nitrate, palladium sulfate, diaminepalladium (II) hydroxide, tetraminepalladium (II) chloride, and the like.
[0029] A Group IVA (IUPAC 14) metal component is another essential ingredient of the catalyst of the present invention. Of the Group IVA (IUPAC 14) metals, germanium and tin are preferred and tin is especially preferred. This component may be present as an elemental metal, as a chemical compound such as the oxide, sulfide, halide, oxychloride, etc., or as a physical or chemical combination with the porous carrier material and/or other components of the catalyst. Preferably, a substantial portion of the Group IVA (IUPAC 14) metal exists in the finished catalyst in an oxidation state above that of the elemental metal. The Group IVA (IUPAC 14) metal component optimally is utilized in an amount sufficient to result in a final catalyst containing about 0.01 to about 5 wt-% metal, calculated on an elemental basis, with best results obtained at a level of about 0.1 to about 2 wt-% metal.
[0030] A Group IVA (IUPAC 14) metal component is another essential ingredient of the catalyst of the present invention. Of the Group IVA (IUPAC 14) metals, germanium and tin are preferred and tin is especially preferred. This component may be present as an elemental metal, as a chemical compound such as the oxide, sulfide, halide, oxychloride, etc., or as a physical or chemical combination with the porous carrier material and/or other components of the catalyst. Preferably, a substantial portion of the Group IVA (IUPAC 14) metal exists in the finished catalyst in an oxidation state above that of the elemental metal. The Group IVA (IUPAC 14) metal component optimally is utilized in an amount sufficient to result in a final catalyst containing about 0.01 to about 5 wt-% metal, calculated on an elemental basis, with best results obtained at a level of about 0.1 to about 2 wt-% metal.
[0031] The Group IVA (IUPAC 14) metal component may be incorporated in the catalyst in any suitable manner to achieve a homogeneous dispersion, such as by coprecipitation with the porous carrier material, ion-exchange with the carrier material or impregnation of the carrier material at any stage in the preparation. One method of incorporating the Group IVA (IUPAC 14) metal component into the catalyst composite involves the utilization of a soluble, decomposable compound of a Group IVA (IUPAC 14) metal to impregnate and disperse the metal throughout the porous carrier material. The Group IVA (IUPAC 14) metal component can be impregnated either prior to, simultaneously with, or after the other components are added to the carrier material. Thus, the Group IVA (IUPAC 14) metal component may be added to the carrier material by commingling the latter with an aqueous solution of a suitable metal salt or soluble compound such as stannous bromide, stannous chloride, stannic chloride, stannic chloride pentahydrate; or germanium oxide, germanium tetraethoxide, germanium tetrachloride; or lead nitrate, lead acetate, lead chlorate and the like compounds. The utilization of Group IVA (IUPAC 14) metal chloride compounds, such as stannic chloride, germanium tetrachloride or lead chlorate is particularly preferred since it facilitates the incorporation of both the metal component and at least a minor amount of the preferred halogen component in a single step. When combined with hydrogen chloride during the especially preferred alumina peptization step described hereinabove, a homogeneous dispersion of the Group IVA (IUPAC 14) metal component is obtained in accordance with the present invention. In an alternative embodiment, organic metal compounds such as trimethyltin chloride and dimethyltin dichloride are incorporated into the catalyst during the peptization of the inorganic oxide binder, and most preferably during peptization of alumina with hydrogen chloride or nitric acid.
[0032] It is within the scope of the present invention that the catalyst composites may contain additional other metal components as well. Such metal modifiers may include rhenium, cobalt, nickel, indium, gallium, zinc, uranium, dysprosium, thallium, and mixtures thereof. Catalytically effective amounts of such metal modifiers may be incorporated into the catalysts by any means known in the art to effect a homogeneous or stratified distribution.
[0033] The catalysts of the present invention may contain a halogen component, comprising either fluorine, chlorine, bromine or iodine or mixtures thereof, with chlorine being preferred. Preferably, however, the catalyst contains no added halogen other than that associated with other catalyst components.
[0034] The catalyst composite is dried at a temperature of from about 100° to about 320° C. for a period of from about 2 to about 24 or more hours and, usually, calcined at a temperature of from about 400° to about 650° C. in an air atmosphere for a period of from about 0.1 to about 10 hours until the metallic compounds present are converted substantially to the oxide form. If desired, the optional halogen component may be adjusted by including a halogen or halogen-containing compound in the air atmosphere.
[0035] The resultant calcined composites optimally are subjected to a substantially water-free reduction step to ensure a uniform and finely divided dispersion of the optional metallic components. The reduction optionally may be effected in the process equipment of the present invention. Substantially pure and dry hydrogen (i.e., less than 20 vol. ppm H2O) preferably is used as the reducing agent in this step. The reducing agent contacts the catalyst at conditions, including a temperature of from about 200° to about 650° C. and for a period of from about 0.5 to about 10 hours, effective to reduce substantially all of the Group VIII metal component to the metallic state. In some cases the resulting reduced catalyst composite may also be beneficially subjected to presulfiding by a method known in the art such as with neat H 2 S at room temperature to incorporate in the catalyst composite from about 0.05 to about 1.0 wt-% sulfur calculated on an elemental basis.
EXAMPLES
[0036] The following examples are presented only to illustrate certain specific embodiments of the invention, and should not be construed to limit the scope of the invention as set forth in the claims. There are many possible other variations, as those of ordinary skill in the art will recognize, within the spirit of the invention.
Example I
[0037] Samples of catalysts comprising zeolites were prepared for comparative pilot-plant testing. First, a catalyst A was prepared to represent a prior art catalyst for use in a process of isomerization of ethylbenzene to para-xylene with minimal benzene formation
[0038] Catalyst A contained SM-3 silicoaluminophosphate prepared according to the teachings of U.S. Pat. No. 4,943,424 and had characteristics as disclosed in the '424 patent. Following the teachings of U.S. Pat. No. 5,898,090, catalyst A was composited with alumina and tetramine platinic chloride at a platinum level of 0.4 wt-% on an elemental basis. The composite comprised about 60 wt-% SM-3 and 40 wt-% alumina, and then the catalyst was calcined and reduced, with the product labeled as Catalyst A.
Example II
[0039] Catalysts were prepared containing MTW-type zeolite prepared in accordance with U.S. Pat. No. 4,452,769, but achieving varying amounts of mordenite impurity. To a solution of 0.4 grams sodium hydroxide in 9 grams distilled water was added 0.078 g aluminum hydroxide hydrate and stirred until dissolved. A second solution of 1.96 grams of methyltriethylammonium halide (MTEA-Cl, note here the chloride form was used instead of the bromide form) in 9 grams distilled water was prepared and stirred until dissolved. Then, both solutions were stirred together until homogenized. Next, 3 grams of precipitated silica was added, then stirred for 1 hour at room temperature and sealed in a Teflon-lined autoclave for 8 days at 150° C. Zeolite type MTW was recovered after cooling, filtering, and washing with distilled water. After drying a product of 5 Na 2 O:1.25Al 2 O 3 :50SiO 2 :1000H 2 O:10(MTEA-Cl) with a BET 454 m 2 /g, was obtained. X-ray diffraction analysis indicated that the product was 100 wt-% MTW type zeolite.
[0040] To form catalyst B, about 10 wt % of the dry 100 wt-% MTW-zeolite was composited with about 90 wt % alumina to form extruded shaped catalyst particles. The particles were then metal-impregnated using a solution of chloroplatinic acid. Upon completion of the impregnation, the catalyst was dried, oxidized, reduced, and sulfided to yield a catalyst containing about 0.3 wt-% platinum and 0.1 wt-% sulfur. The finished catalyst was labeled catalyst B.
Example III
[0041] Catalysts A and B were evaluated for ethylbenzene isomerization to para-xylene using a pilot plant flow reactor processing a non-equilibrium C 8 aromatic feed having the following approximate composition in wt-%:
Toluene 0.2 C 8 Non-aromatics 8.3 Ethylbenzene 26.8 Para-xylene 0.9 Meta-xylene 42.4 Ortho-xylene 21.0 C 9 + Non-aromatics 0.4
[0042] This feed was contacted with catalyst at a pressure of about 620 kPa, a liquid hourly space velocity of 3, and a hydrogen/hydrocarbon mole ratio of 4. Reactor temperature was adjusted to effect a favorable conversion level. Conversion is expressed as the disappearance per pass of ethylbenzene, and C 8 aromatic ring loss is primarily to benzene and toluene, with smaller amounts of light gases being produced. Results were as follows:
Catalyst A B Temperature ° C. 386 371 p-xylene/xylenes 22.5 22.3 EB conversion, wt-% 31 38 Benzene yield, wt-% 0.25 0.10 C 8 Ring loss 2.5 2.5
[0043] Accordingly, catalyst B showed better conversion of ethylbenzene while minimizing the yield of undesired benzene as compared to catalyst A of the prior art. Note that the “C 8 ring loss” is in mol % defined as “(1-(C 8 naphthenes and aromatics in product )/(C 8 naphthenes and aromatics in feed ))*100”, which represents material that has to be circulated to another unit in an aromatics complex. Such circulation is expensive and a low amount of C 8 ring loss is a favorable feature of the catalyst of the present invention.
Example IV
[0044] Similarly, additional batches of MTW-type zeolite were prepared according the procedure outlined above in Example II. However due to variations in stirring and seed crystals as well as other inhomogeneous effects among the vessels used, resulting batches were discovered to have various amounts of impurities at a silica-to-alumina ratio of about 34. The impurities were determined to be a mordenite-type zeolite by using x-ray diffraction methods. To understand the effect of the impurity, various samples were obtained and made into catalysts.
[0045] Catalyst C was prepared with the same material as Catalyst B, 100 wt-% MTW. Catalyst D was prepared with a zeolitic composite comprising 90 wt-% MTW and 10 wt-% mordenite. Catalyst E was prepared with a zeolitic composite comprising 80 wt-% MTW and 20 wt-% mordenite. Finally, Catalyst F was prepared with a zeolitic composite comprising 50 wt-% MTW and 50 wt-% mordenite to illustrate a catalyst with substantial mordenite impurity and thus is not considered a catalyst within the scope of the invention.
[0046] Catalysts C through F were formed into extruded particles using about 5 wt-% of the zeolitic composite material above and about 95 wt-% alumina binder. The particles were then metal-impregnated using a solution of chloroplatinic acid. Upon completion of the impregnation, the catalysts were dried, oxidized, reduced, and sulfided to yield catalysts containing about 0.3 wt-% platinum and 0.1 wt-% sulfur. The finished catalysts were labeled respectively, catalysts C through F.
Example V
[0047] Catalysts C through F were evaluated for C 8 aromatic ring loss using a pilot plant flow reactor processing a non-equilibrium C 8 aromatic feed having the following approximate composition in wt-%:
C8 Non-aromatics 7 Ethylbenzene 16 Para-xylene <1 Meta-xylene 52 Ortho-xylene 25
[0048] This feed was contacted with a catalyst at a pressure of about 620 kPa, a liquid hourly space velocity of 4, and a hydrogen/hydrocarbon mole ratio of 4. Reactor temperature was adjusted between about 370 to 375° C. to effect a favorable ethylbenzene conversion level.
[0049] Results were as follows:
Catalyst C D E F p-xylene/xylenes 22.3 22.3 22.3 22.3 C 8 Ring loss 2.6 3.3 3.6 5.4
[0050] Accordingly, catalyst C showed minimum ring loss, and catalysts D thru F illustrated that mol-% ring loss increased with mordenite impurity level. Such circulation is expensive and a low amount of C 8 ring loss is a favorable feature of the catalysts of the present invention, which contain MTW-type zeolite substantially free of the mordenite impurity.
Example VI
[0051] Catalyst G was prepared to illustrate a bimetallic catalyst of the present invention. Catalyst G was prepared with the same zeolitic material of Catalyst B, 100 wt-% MTW type zeolite, and formed into extruded particles using about 5 wt-% of the zeolitic material and about 95 wt-% alumina binder. The particles were then metal-impregnated using a first aqueous solution of tin chloride in a cold rolling evaporative impregnation vessel for about one hour and then steamed to dryness. The tin-impregnated base was calcined at 550° C. in air for two hours.
[0052] Then a second aqueous platinum impregnation was conducted with chloroplatinic acid and similarly cold rolled for one hour and steamed to dryness. The catalyst was then oxidized and reduced to produce a finished catalyst containing about 0.3 wt-% of platinum and about 0.1 wt-% of tin, which was labeled as catalyst G.
Example VII
[0053] Catalysts B and G were evaluated for stability in ethylbenzene isomerization to para-xylene using a pilot plant flow reactor processing a non-equilibrium C 8 aromatic feed having the same approximate composition as Example III above. This feed was contacted with catalyst at a pressure of about 690 kPa, a weighted hourly space velocity of about 9.5, and a hydrogen/hydrocarbon mole ratio of 4. Reactor temperature was set at 385° C. and conversion was allowed to decline over time.
[0054] Results showed that catalyst G had about a 5 wt-% lower initial conversion of ethylbenzene when compared to catalyst B, but that catalyst G had a deactivation rate that was only about two-thirds that of catalyst B. Deactivation rate was determined based on the rate of decline of ethylbenzene conversion over time under the test conditions above.
[0055] When a second comparative test was conducted at the same conditions as above except using a 3 weighted hourly space velocity, the ethylbenzene conversion performance of catalyst G exceeded the performance of catalyst B after about 130 hours on stream. Thus, catalyst G showed that superior stability, in terms of decreased deactivation, provides long term value for the isomerization of ethylbenzene into xylenes and that increased yields are produced when conversion is averaged over an extended time period. Moreover, it should be noted that the catalyst performance in terms of C 8 ring loss was about equivalent between catalyst B and catalyst G. | A process for isomerizing ethylbenzene into xylenes such as para-xylene using a bimetallic zeolitic catalyst system based on MTW-type zeolite is disclosed. Preferably the two metals are platinum and tin. The invention obtains a stable and improved yield of xylenes such as para-xylene without excess benzene production by dealkylation. The zeolitic silica-to-alumina ratio ranges from 20 to 45. Use of MTW substantially free of mordenite improves yields and integrated aromatics complex economics by reducing undesirable aromatic ring-loss reactions. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
An improvement upon the invention disclosed in the joint applicants' U.S. Pat. No. 4,106,031, entitled AUTOMATIC DRAFTING DEVICE, as well as copending Ser. No. 922,629, filed July 7, 1978.
BACKGROUND OF THE INVENTION
Field of the Invention
An automatic drafting instrument of the type wherein a plurality of stylographic pens are reciprocably supported with respect to a drafting surface. Such pens include sealing elements which are laterally slidable into and out of contact with the writing pen tip, respectively, as the pen is raised to its storage position and as the pen is dropped to its writing position. The present invention provides a linkage which lifts the pen from the sealing element without sliding of the sealing element across the pen tip.
SUMMARY OF THE INVENTION
The invention refers to an automatic drawing apparatus containing at least one tube writer in a writing head. The tube writer is movable from an elevated storage position, in which its forward end is situated above the writing base, to a lowered drawing position, in which its forward end is in contact with the drawing base. The apparatus has a sealing element which, in storage position, seals off the forward end of the tube writer and, during writing, is withdrawn and held to the side of the tube writer.
With the drawing apparatus described in earlier filed application Ser. No. 922,629, it is possible to seal off the writing tube while in storage position by means of a sealing element, which is swung or moved to the side of the writing tube, so as not to interfere with the writing process. The use of this sealing element ensures that the tube writer is always ready for drawing, even when left in storage position for an extended time, thus eliminating any interference with the automatic functioning of the drawing apparatus.
In this prior drawing apparatus the sealing element and, in certain instances, even the tube writer can be damaged, (especially if the diameter of the tube or writing tip is particularly small), when the sealing element is swung to the side while still in contact with the writing tube. This has been necessary to stop the sealing function on the one hand and to move the tube writer down to the writing position on the other. The problem with the prior apparatus is that the forward end of the tube writer is in direct contact with the upper surface of the sealing element during the first part of the swinging process.
In an attempt to alleviate this problem, it has been suggested (German Pat. No. P 27 07 2588), that a blocking apparatus be installed that could be engaged with the tubewriter and which would hold the tube writer in its storage position until the sealing element had been swung completely to the side and out of the path of the tube writer. This means that the sealing element could be swung out of sealing position without the forward end of the writing tube coming in contact with the sealing element during the swinging process, thus eliminating the possibility that the weight of the tube writer and possibly that of a pen be forced onto the sealing element.
With the prior drawing apparatus, however, difficulties could arise. The sealing element was moved out of sealing position by an essentially lateral movement in relation to the writing tube. During the sealing process a certain deformation, i.e. indentation, is caused by the pressure of the forward end of the writing tube on the sealing element, and in the process of moving the sealing element away from the writing tube in a lateral direction the sealing element can become grooved or torn, or, as is the case with tube writers for small line widths, the tube writer itself can be damaged.
To avoid these problems, it has been suggested (German Pat. No. P 27 50 937.1) that the sealing element be moved down and away in the first segment of the process of moving it from its sealing position to its lateral position and then out of the tube writer's lowering area in the second segment of the process. The tube writer is held in the storage position by the blocking apparatus until the second segment of the moving process is completed.
Damage to the sealing element and/or to fine line pens was effectively eliminated by the above-described two phase movement of the sealing element since the sealing element moved first down and then, after separation from the writing tube, to the side. However, the two movement phases travel a relatively longer path and thus require a relatively longer period of time. This meant that there was a relatively long time lag when starting to draw.
With this discovery, the sealing element of an automatic writing apparatus described in U.S. application Ser. No. 922,629 can be moved quickly and without damage to itself and/or to the tube writer to and from sealing position.
As a solution to this problem, an automatic writing apparatus according to U.S. Ser. No. 922,629 will be so equipped that the tube writer can be elevated to an intermediate position in which the forward end of its writing tube is situated above the sealing element, and that the tube writer with the sealing element moved to the side is movable from the intermediate position to the drawing position.
With the drawing apparatus constructed accordingly, the tube writer is first lifted to an intermediate position so that the writing tube separates from the sealing element. Then the sealing element is moved out of the lowering area of the tube writer with a simple lateral movement. The tube writer is then lowered from the intermediate position to the writing position, so that the writing tip comes in contact with the writing base.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially fragmentary side elevation, showing a tube writer in an automatic drawing apparatus, having a sealing element, engaging the writing tip and an assembly for moving the tube writer and the sealing element.
FIG. 2 is a schematic of FIG. 1, showing the writing tip and sealing element in the same operational position.
FIG. 3 is a schematic, showing the tube writer in intermediate position.
FIG. 4 is a schematic, showing tube writer in drawing position.
FIG. 5 is a schematic, showing the tube writer in intermediate position and with the sealing element moved to the side.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The tube writer 1 depicted in FIG. 1 is arranged in a drawing head 3 which is illustrated schematically. The tube writer 1 reveals a cylindrical section 4 in which the writing tube tip 2 is secured. The cylindrical section 4 serves to guide the tube writer in area 5 of the drawing head as do the ring ridges 6 and 7 in the rear part of the tube writer.
The writing tube 2 rests on a sealing element 9 made of elastic material, so that an effective seal is produced on the writing tube in the position illustrated in FIGS. 1 and 2, thus preventing the drawing ink from drying out. The sealing element 9 is part of a slide 8 which is supported in a housing part 10 and to which the sealing element 9 is attached by a screw 11. In the upper part of the slide 8 there is a slot or groove 12 opening to the top with side walls 13 and 14. The slide 8 is held in the position indicated in FIG. 1 by a compression spring 17. This compression spring 17 is braced on the one side against the slide 8 and on the other side against the housing of a magnet 15 whose pestle 16 is connected to the slide 8.
Above slide 8 and to the side of the tube writer a contact lever 18 is attached at its stationary axis 19. This lever 18 extends through a side opening in housing 10 and in the drawing head 3 and through the area between ring ridges 6 and 7. At point 20 on this lever 18 one end of the first lever 21 is attached so as to rotate. The other end of the first lever 21 is attached at point 22 to one end of the second lever 23 so as to rotate. This second lever 23 is attached at a stationary axis 24 so as to rotate and supports a peg or bolt 28 beneath and running parallel to the stationary axis 24. This peg or bolt 28 extends into a furrow within carrier element 27 which is attached to the pestle 26 of the magnet 25. The free end of lever 23 opposite the rotational attachment point 22 extends into groove 12 and lies against the side wall 13 as illustrated.
The position depicted in FIG. 1 is the storage position in which the writing tube or tip 2 is sealed off by the sealing element 9. This position is also schematically shown in FIG. 2.
To bring the tube writer into writing position, the magnet 25 is activated and the pestle 26 is moved to the left, thereby swinging lever 23 clockwise around its stationary axis 24 so that the free end of this lever comes in contact with the side wall 14 of slot 12 in slide 8, and so that lever 21 and 23 come into a position where their longitudinal axes come into essentially a straight line (FIG. 3). As a result of this movement of levers 21 and 23, the contact lever 18 is swung up somewhat around its stationary axis 20, so that its free end comes in contact with the lower surface of ring ridge 6, thus raising the tube writer 1 into the intermediate position illustrated in FIG. 3. In this position the lower end of the writing tube 2 is no longer in contact with the sealing element 9.
As illustrated in FIG. 4 and when the motion of pestle 26 of the magnet 25 continues to the left, the free end of the lever 23 is swung farther clockwise, and by engaging the side wall 14 of slot 12, the slide 8 is moved against the pressure of compression spring 17 to the left, while at the same time the free end of the contact lever 18 is moved farther down. Since the movement of pestle 26 of magnet 25 is practically instantaneous, the free end of the contact lever 18 disengages immediately after the levers 21 and 23 as illustrated in FIG. 3 align themselves. The tube writer then drops into its writing position in which the writing tube comes in contact with the writing base, as illustrated in FIG. 4. With the tube writer in writing position, the free end of the contact lever 18 is located immediately above the ring ridge 7 and thereby prohibits the tube writer's slamming against the drawing base while dropping down.
Furthermore, in the position depicted in FIG. 4, the magnet 15 can be activated to hold the slide 8 to the side against the compression spring 17, and the magnet 25 can be switched off. This securing of the slide 8 and with it, of the sealing element 9, in the side position, makes it possible to raise and lower the tube writer 1 while drawing (as in making a dotted line) without the sealing element 9 coming in contact with the writing tube 2 with every stroke. The intent is that the writing tube 2 be sealed off only when the tube writer 1 is lifted from the drawing base for a predetermined period of time, e.g. 15 seconds, since it would be less likely that such a pause would occur in the normal drawing process, and that such a pause would normally signal the end of drawing.
When the tube writer is to be moved from the writing position in which the slide 8 is held to the side by the magnet 15, magnet 25 is switched over so that the pestle 26 moves to the right. This swings levers 21 and 23 from the position depicted in FIG. 4 to the position depicted in FIG. 5, so that the contact lever 18 lifts the tube writer 1 with its free end to the intermediate position. Since, however, the free end of lever 23 (as shown in FIG. 5) rests against side wall 13 of slot 12 in the slide 8 (still pushed to the left), levers 21 and 23 cannot be swung past their aligned position to a position as shown in FIG. 2, but are pulled while still in contact with the side wall 13 by the activation of magnet 25 to a nearly aligned position in which the tube writer is to the intermediate position, illustrated in FIG. 5.
In case the tube writer should need to be lowered again before magnet 15 is switched off, magnet 25 is switched on once more and its pestle 26 is moved to the left, so that the tube writer 1 is lowered to writing position as described above and according to FIG. 4.
If within the predetermined time span, the tube writer does not lower, magnet 15 is deactivated and compression spring 17 moves the slide 8 to the right, so that the sealing element 9 comes under the writing tube 2, as illustrated in FIG. 3. As a result of the movement of side wall 13 of slot 12 to the right brought about by the process immediately above, the pestle 26 of the magnet 25 continues its motion to the right and thereby brings levers 21 and 23 and, with them, contact lever 18 to the position indicated in FIG. 2. This again lowers the tube writer 1 to its storage position and seals off the writing tube 2. | A sealing element for an automatic drafting pen with a tubular tip wherein a reciprocating horizontal actuating means that acts through a linkage operates a horizontal slide that in one position permits the pen to contact the drafting surface and in a second position seals the pen with the horizontal slide. | 1 |
FIELD OF THE INVENTION
The invention concerns an earth boring machine with a frame, a slide linearly movable on the frame, which slide has an apparatus for holding and rotatably driving a boring rod, and a forward feed drive for moving the slide parallel to the boring direction.
BACKGROUND OF THE INVENTION
In the creation of an earth bore, the forward feed drive of such an earth boring machine moves the slide relatively slowly forwardly against a large force exerted by the earth, which force is transmitted to the slide through the boring rod. Previous earth boring machines have for the forward feed drive a cylinder arranged on the frame from which a piston is moved outwardly in its axial direction to push the slide forwardly. A disadvantage is that in such a drive, during the extension and retraction of the piston respectively, greatly different forces are created. The maximum force can therefore be deployed only either for the creation of a bore or for the pulling of the boring rod from the bore.
If the piston becomes fully extended, the boring rod is disconnected from the slide and thereafter the piston is retracted with the slide also being retracted on the frame oppositely to the forward feed direction. Thereafter, an additional rod member is fastened with one end to the slide and with its other end to the boring rod, before the piston is again driven forwardly to extend the bore. The frame of such earth boring machines extends at least over the length of the cylinder with its piston extended, and therefore, at least over double the length of a rod member. Where only little room is available for placement of the frame, such an earth boring machine cannot be used.
The frames of such earth boring machines can be built with shorter length. The publication DE 196 45 222 A1 discloses an earth boring machine on the frame of which is arranged a forward feed drive, and chains and chain wheels for driving a slide, which slide is fastened to an upper run of one of the chains. Such a construction requires a forward feed drive of high power for driving the slide at a low rotational speed and a large rotary moment. Therefore, arranged on the frame is an especially high power motor with a speed reducing drive which is expensive and requires a large amount of room.
If the chains are driven by an hydraulic motor, there arises the disadvantage that the hydraulic motor when operating at low rotational speeds has a very poor efficiency. This means that, especially in the case of hard earths, which demand a slow forward feed, the maximum rotational moment of the hydraulic motor becomes indeed needed but, because of the slow rotational speed, it cannot be used.
Further, during the forward feed of the slide against the resistance of the earth, large forces come into effect between the chain and the slide. This requires the use of especially robust chains and chain wheels likewise requiring much space so they are also disadvantageous in regard to constructional size and/or the space requirement of such compact boring mechanisms.
It is the object of the invention to provide an earth boring machine of the above kind which with an especially small space requirement creates in a simple way a large force for moving the slide in and opposite to the forward feed direction.
SUMMARY OF THE INVENTION
This object is solved by an earth boring machine in which the forward feed drive has a rotationally drivable forward feed spindle arranged on the frame, which spindle is received by a spindle nut non-rotatably fixed to the slide.
The use of a forward feed spindle and a spindle nut for the drive of the slide in the earth boring machine of the invention has the advantage that the driving rotational moment by way of the forward feed spindle and the spindle nut is converted directly into a forward feed force exerted onto the slide. A drive motor creates with its power a rotary moment which drives the forward feed spindle in a rotational motion at a given rotational speed. The pitch of the threads of the forward drive spindle, in the case of a given motor power and rotational speed, determines the forward feed force and the forward feed speed of the slide. The smaller the pitch of the thread, the smaller is the forward feed speed and the larger the forward feed force of the slide.
According to the inventive idea, the pitch of the forward feed spindle is so designed that the forward feed speed of the slide is very small and the forward feed force transmitted to it very large. Both of these values can be changed by the use of other forward feed spindles and spindle nuts with other thread pitches, and thereby the particular requirements of a current boring process can be accommodated. These advantageous effects are achieved without the use of a separate speed reducing drive. The frame of the earth boring machine can therefore be made in an especially space-saving way.
In a preferred embodiment of the inventive earth boring machine, the slide is movable relative to the spindle nut along an axial extent which is at least so long as the axial length of a thread for connecting two rod members and which axial extent is limited by stops fixed to the slide. During the emplacement and removal of a rod member between the boring rod and the slide, there appears between the boring rod and the slide axially directed tension or compressive forces. During the threading on of an additional rod member, for example, there is exerted on to the threads of the receiver of the slide a force in the forward feed direction and onto the thread of the boring rod an oppositely directed force. Because of the high resistance of the boring rod sticking into the earth on one hand and the spindle nut on the other hand against an axial movement when the forward feed drive is at rest, there exists the danger that the threads on the boring rod and on the receiver are abraded by the high axial forces during the threading of the parts to one another or from one another. In the preferred embodiment, the slide gives way against the tension or compression force applied to it through the receiver and during the making or loosening of the threaded connection is driven relative to the fixed in place spindle nut axially along a stretch of displacement. In this way, damage to the threads is avoided. The length of the movable stretch corresponds about to the length of the threads and is limited by axial stops fixed to the slide. These stops transmit therefore the forward feed force from the spindle nut to the slide when the forward feed drive is in operation.
This embodiment can be optimized by pre-tensioning the slide by means of a tension element in one of the axial stop positions. Thereby the movement of the slide relative to the spindle nut either during the threading from one another or the threading to one another of the receiver and the rod member is supported and the tension or compression force is reduced.
In this case, it is especially advantageous if the slide is pre-tensioned in the direction of the forward movement of the boring rod, by a helical spring designed as a compression spring surrounding the forward feed spindle and working between the spindle nut and, for example, the axially forward stop. In this way, for one thing, the insertion of an additional rod member is made easier. The slide is first driven in the forward feed direction until the threads of the rod member and the receiver come into contact with one another. Then the spindle nut is moved further against the force of the compression spring for about the length of the threads. The thereby existing tension of the spring is then used itself for the forward pushing of the slide while the threads of the receiver are threaded with those of the rod member by actuation of the rotary drive. An interruption of the actuation of the rotary drive, in order to relieve the slide from tension forces during the threading together of the windings with the help of the forward feed drive, is not necessary.
As another thing, the threads of the spindle nut and of the spindle are protected against the direct effect of impacts directed in the forward feed direction, which impacts may appear if the borer encounters relatively large stones. These short-term impulses are conveyed from the boring rod through the slide to the forward axial stop and push the slide against the forward feed direction and against the force of the compression spring, which is thereby compressed. At the same time, the compression spring increases the forward feed force exerted onto the slide and supports the borer in overcoming the encountered obstacle. The spindle nut and spindle do not become loaded with additional axial force.
In a further embodiment, a forward feed motor is arranged in line with the longitudinal axis of the forward feed spindle for the direct rotational drive of the forward feed spindle. With this arrangement, the rotational moment of the forward feed motor is transferred directly and without loss to the forward feed spindle.
In another preferred embodiment of the inventive boring mechanism, a forward feed motor for the rotational drive of the forward feed spindle is arranged laterally of the longitudinal axis of the spindle and is connected with the spindle through a drive. By this arrangement of the forward feed motor laterally of the forward speed spindle, the extent of the frame of the boring mechanism in the direction of the spindle axis is especially small.
In a further preferred embodiment, the forward drive spindle is surrounded by a concave cone spring (telescopic spring) or by a bellows. In this way the forward drive spindle is protected from becoming dirty without the movement of the slide being hindered.
In another preferred embodiment, the threads of the forward drive spindle and of the spindle nut are formed in profile like ball bearing races and in the interior of the spindle nut are filled with balls. Because of the relatively low rolling frictional forces between the balls and the threads of the spindle nut and the forward drive spindle, the loss of rotational drive moment is reduced, in comparison to the substantially higher sliding frictional forces which would exist between the threads of the forward drive spindle and the spindle nut in the absence of this bearing.
In a further embodiment, a ball bearing is provided for supporting each of the ends of the forward feed spindle on the frame. The ball bearings absorb axial as well as radially-directed forces and are especially saving in space.
Further features and advantages of the invention will be apparent from the following description of an exemplary embodiment of the inventive earth boring machine taken in connection with the accompanying drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings are:
FIG. 1 a simplified side view of the boring machine.
FIG. 2 a perspective illustration of the boring machine.
FIG. 3 a plan view of a pit carriage of the boring machine.
FIG. 4 an axial partial section of the slide shown in its rear stop position.
FIG. 5 a radial section taken along the line V—V in FIG. 4 .
FIG. 6 an axial partial section of the slide in its forward stop position.
FIG. 7 a radial section taken along the line VII—VII in FIG. 6 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a simplified side view of an earth boring machine 10 with a pit carriage 12 , which is set up in a dug starting pit 16 in the earth 14 . The pit carriage 12 has a frame 18 with a forward feed spindle 20 connected with a slide 22 to which the rear end of a boring rod 24 is fastened. The boring rod 24 extends with its boring head 26 essentially horizontally outwardly from the frame 18 into the earth 14 .
FIG. 2 shows a detailed perspective view of the earth boring machine 10 without the boring rod 24 . The frame 18 of the pit carriage 12 has a forward wall 28 and a rear wall 30 . These walls are rigidly connected, at their lower lateral sections, by two rectangular profile bars 32 and 34 extending between the walls, and at their upper lateral sections by two adjustable length tension struts 36 and 38 , which with their dish-shaped end surfaces 40 brace the frame 18 of the earth boring machine 10 against the walls of the starting pit 16 (see FIG. 1 ). The forward feed spindle 20 is rotatably supported on the walls 28 and 30 .
Further, two cylindrical guide rails 44 and 46 extend between the forward wall 28 and the rear wall 30 on both sides of and somewhat above the forward feed spindle 20 , which guide rails, as illustrated in FIG. 2, are surrounded by a cover 42 in the form of a concave cone spring. A slide 22 of nearly rectangular shape is supported on the guide rails 44 and 46 for sliding movement along the length of the spindle axis. Two hollow cylinders 48 and 50 , which receive the guide rails 44 and 46 , and which are rigidly connected with the body of the slide, extend in the axial direction through the slide 22 near the lower lateral ends of its body. The connection of the slide 22 with the forward drive spindle 20 is described below in connection with FIG. 4 through FIG. 7 .
On the slide 22 above the forward feed spindle 20 is arranged a rod receiver 52 with a rotatable threaded pin 56 fastened to a bearing 54 and extending in the forward feed direction. The boring rod 24 is tightly screwed onto the threaded pin 56 . For the rotary drive of the boring rod 24 , the rod receiver 52 is connected with a rotary drive motor 58 by means of a non-illustrated drive, which motor is fastened to the side of the slide facing in the forward feed direction laterally of the rod receiver 52 .
For the rotary drive of the forward feed spindle 20 , on the side of the forward wall 28 facing in the forward feed direction is provided a chain drive 60 with a drive wheel 62 , a chain 64 , and drive wheel 66 . The drive wheel 66 is non-rotatably connected with the forward end of the forward feed spindle which extends forwardly through and beyond the forward wall 28 . To avoid dirt, the chain drive 60 is surrounded from outwardly in by a protective cover 68 fastened to the forward wall 28 .
The drive wheel 62 of the chain drive 60 is connected with a forward feed motor 70 which, in the illustration of FIG. 2, is not visible and which is described in more detail below in connection with FIG. 3 .
On the frame 18 of the pit carriage 12 is a vertically extending carrier 72 for a control console 74 for controlling the functions of the earth boring machine. The carrier 72 is hollow and carries the non-illustrated control conductors for connecting the operating elements 76 of the control console 74 with the drive apparatuses of the pit carriage 12 .
FIG. 3 shows in a simplified plan view the pit carriage 12 , to which the forward feed motor 70 for rotatably driving the forward feed spindle 20 is fastened laterally of the forward feed spindle on the side of the forward wall 28 facing opposite to the forward feed direction.
FIG. 4 shows by way of an axial partial section of the slide 22 its support on the forward feed spindle. First one sees in non-sectional illustration the upper section of the slide body having on its forward side the rod receiver 52 extending in the forward feed direction as well as the rotary drive motor 58 , and on its rear side having a housing 78 for connection with flushing water conductors. The housing 78 has a sealed, rotatably supported inner shaft (not illustrated) which is connected with the boring rod through the rod receiver. The hollow cylinder 48 extends in the axial direction to both sides of the slide 22 . In sectional illustration is shown a support housing 80 arranged on the lower section of the slide 22 , which housing 80 surrounds the forward speed spindle 20 , a spindle nut 82 supported on the spindle, and a helical spring 84 . The support housing 80 has a cylindrical outer profile and is made up of three housing parts; namely, a forward housing body 86 rigidly formed on the slide 22 ; an intermediate ring 88 ; and a rear housing body 90 . The three housing parts are connected by screws 92 .
At both axial ends of the support housing 80 are formed tubular supports 94 and 96 , which extend in the axial direction. During operation of the earth boring machine on each of the supports 94 and 96 , a portion of the cover 42 , illustrated in FIG. 2, is supported.
The forward housing body 86 has a forward wall 98 with a circular shaped opening in its middle, the edge of which closely surrounds the forward feed spindle 20 . Forwardly of the intermediate ring 88 , the outer and inner profile of the forward housing body widens step-wise to a flange 100 . The intermediate ring 88 lies on the flange 100 , and the intermediate ring in turn, lies on outer ring flange 100 fixedly formed on the rear housing body 90 . The flange 100 , the intermediate ring 88 , and the ring flange 102 have bores 103 for receiving the screw 92 . The rear housing body 90 has a rear wall 104 with a circular opening in its middle, which closely surrounds the forward feed spindle 20 . With its side wall 106 , the rear housing body 90 is received in the interior of the forward housing body 86 and forms together with this a stepless inner profile of the support housing 80 , which closely surrounds the spindle nut 82 at its circumference. In the axial direction, the support housing 80 has play room for movement of the spindle nut 82 between the forward wall 98 and the rear wall 104 . A movement of the spindle nut 82 in the direction toward the forward wall 98 takes place against a force of the intermediately supported helical spring 84 which is formed as a compression spring.
FIG. 5 shows a radial section of the support housing 80 and of the forward feed spindle along the line V—V of FIG. 4 . The support housing 80 as seen in this transverse section has a nearly rectangular inner profile.
FIG. 6 shows a partial axial section of the slide 20 in its forward stop position. FIG. 6 differs from FIG. 4 in regard to the position of the spindle nut 82 inside of the support housing 80 . The spindle nut is contact with the rear wall 104 so that the helical spring 84 is unloaded.
FIG. 7 shows a radial section along the line VII—VII in FIG. 6 . The inner profile of the support housing 80 surrounds the spindle nut 82 so that it is supported in rotatably fixed condition but is axially movable with rotation of the forward feed spindle 20 . | An earth boring machine 10 with a frame and a linearly movable slide 22 on the frame has an apparatus for holding and rotationally driving a boring rod 24 , and a forward feed drive for moving the slide parallel to the boring direction. The machine with especially small space requirement creates a large force for movement of the slide 22 in and opposite to the forward feed direction. Moreover, the forward feed drive of the earth boring machine 10 has a rotationally drivable forward feed spindle 20 arranged on the frame 18 , which spindle is received by a spindle nut non-rotationally connected with the slide 22. | 4 |
RELATED APPLICATIONS
[0001] This application claims the benefit from U.S. provisional application Serial No. 60/376,228 filed on Apr. 30, 2002, the disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of electronic commerce using portable information devices such as smart cards, personal digital assistants, and the mechanisms used to access these devices. More specifically, the invention relates to systems and methods for using portable information devices to facilitate electronic business transactions. Even more particularly, the invention concerns systems and methods for electronically posting, reserving, purchasing, authenticating and redeeming tickets and vouchers using portable information devices employing public key cryptography.
BACKGROUND OF THE INVENTION
[0003] Every day throughout the world, consumers conduct multi-phase business transactions with suppliers. At each phase of these business transactions, one of the parties may demand that another party to the transaction provide some level of authentication or identification. Additionally, a party may require, as a condition of entry into a multi-phase business transaction, that certain forms of authentication be performed at some or all subsequent phases of the transaction.
[0004] Authentication of multi-phase business transactions may be accomplished in a variety of ways incorporating a wide range of sophistication and accuracy. An example of low-sophistication, low-accuracy authentication is a simple cash transaction in which the critical factor is the authenticity of the cash itself. At the other extreme, a high-sophistication, high-accuracy transaction might be a special event, where notification of the event is by secret invitation, payment is required in advance and admittance is conditioned upon verification of biometric information, such as that obtained through a retinal scan or DNA sample.
[0005] In recent years, portable information devices and integrated circuit cards such as smart cards have emerged as effective devices for facilitating many different types of transactions, as well as for providing a secure means to store the information required by those transactions. In particular, portable information devices have been used to facilitate entry into ticketed events by storing the required ticket information within the device's memory.
[0006] Without loss of generalization, the term portable information device (“PID”) will be used herein to refer to a portable device having a built-in microprocessor and memory, capable of being programmed to store and access personal identifying information and/or financial transaction information, and able to create and/or validate digital signatures and/or digital certificates. Examples of portable information devices include portable computers, hand-held computers, integrated circuit cards, smart cards, mobile computing devices, cellular telephones, personal digital assistants (“PDAs”), wireless pagers and the like.
[0007] Similarly, without loss of generalization, the term “ticket” will be used herein to refer to a document, which may be maintained in electronic form, that serves as a certificate, license or permit. For example, a ticket may be a label for identification. A ticket may also correspond to a token showing that a fare has been paid or that a means of access or passage has been granted. A ticket may additionally record a business transaction or may document an agreed contractual undertaking or may provide instructions corresponding to a specific individual or group of individuals, such as may be provided by a traffic ticket or summons.
[0008] Again, without loss of generalization, the term “consumer” will be used herein to refer to a customer, consumer, member, attendee or person who acquires a ticket according to embodiments of the present invention.
[0009] According to known online ticketing techniques, a ticket is stored on a PID by communicating to the PID the data required to fully describe the ticket, including where necessary administrative information, individual identification information, special instructions, financial data, a venue, a date and time of a scheduled event, and seating information. The PID may also store proof of payment as well as ticket refund information. When a valid PID ticket holder arrives at the scheduled event, the PID is interfaced to an appropriately-configured PID terminal and ticket information located on the PID is extracted and verified. After the ticket is authenticated, the PID terminal may then erase the ticket information from the PID, or may otherwise mark the ticket information as redeemed by any number of methods known in the art.
[0010] Known methods for issuing tickets using PIDs require the ticket information to be stored on the PID itself. Indeed, this local storage is perceived to be a benefit. Once the ticket information has been stored on the PID, ticket authentication and validation can then be accomplished simply by communicating with the PID, first to exchange and authenticate the appropriate identifying information and security keys, and then to transfer the specific ticket information directly from the PID to the ticketing terminal.
[0011] However, while such known methods for issuing and redeeming tickets may appear convenient, they require the PID to store the ticket information. For this reason, when a ticket is purchased, the PID must be inserted into a PID interface terminal, which must communicate with the PID to transfer the required ticketing information. Thus, known methods for issuing and redeeming a given ticket using PID technology require that a consumer either travel to the location of a PID interface terminal or possess a PID interface terminal that is able to communicate with a central ticketing system. Additionally, known PID ticketing methods do not permit external control, modification, and validation of the ticket information stored on the PID.
[0012] Accordingly, there is a need in the art for a system and method for purchasing, issuing and redeeming tickets using PID technology, that meets the basic needs of accessibility, convenience, and fraud protection, and which does not require ticket information to be transferred to the PID, but nevertheless retains the security features of personal information devices and related technology.
SUMMARY OF THE INVENTION
[0013] Embodiments of the present invention are directed to a system and method for purchasing, issuing and redeeming electronic tickets using portable information device (“PID”) technology. Utilizing the accessibility, convenience, and fraud protection features of PIDs, embodiments of the present invention store user identification information on a user's PID, and then, utilizing a ticket server and an authentication device, provide mechanisms to access the PID in order to authenticate and/or validate the user.
[0014] In other aspect, embodiments of the present invention provide a method and system to update a ticket server with authentication data associated with a venue and then share the authentication data with an authentication device. The embodiments include establishing a communication between a consumer's PID and the authentication device, and deciding whether to grant the consumer access to the venue based on the communication.
[0015] In yet another aspect, embodiments of the present invention provide a method and system to update a ticket server with authentication data associated with the status and/or identity of a registered individual, and sharing the authentication data with at least one authentication device. The embodiments include establishing a communication between the PID and one of the authentication devices, and authenticating, based on the communication, the status and/or identify of the registered individual.
[0016] Other systems, methods, features and advantages of the invention will become apparent to one skilled in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages included within this description are within the scope of the invention, and are protected by the accompanying claims.
[0017] Unless specifically stated otherwise as apparent from the following discussions, it is understood that terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data. The data is represented as physical (electronic) quantities within the computer system's registers and memories and is transformed into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] [0018]FIG. 1 is a high-level block diagram of a ticketing system for purchasing, issuing and redeeming electronic tickets using portable information device (“PID”) technology, in accordance with an embodiment of the present invention.
[0019] [0019]FIG. 2 is a representative drawing of a PID, according to an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Embodiments of the present invention will be described in reference to the accompanying drawings, wherein like parts are designated by like reference numerals throughout, and wherein the leftmost digit of each reference number refers to the drawing number of the figure in which the referenced part first appears.
[0021] [0021]FIG. 1 is a high-level block diagram of a ticketing system 100 for purchasing, issuing and redeeming electronic tickets using portable information device (“PID”) technology, in accordance with an embodiment of the present invention. Ticket system 100 may include five functional entities: ticket service center 110 , sales merchant 120 , ticket authenticator 130 , venue merchant 140 and portable information device (“PID”) 150 employing public key cryptography.
[0022] Ticket Service Center 110
[0023] With reference to FIG. 1, ticket service center 110 may include a set of network and database servers that together maintain an active database of sold and unsold ticket assets. Ticket service center 110 may serve multiple roles. However, its primary functions are to broker and service tickets. In those capacities, ticket service center 110 carries out several related tasks. Ticket service center 110 may receive requests to market and sell tickets from sales merchant 120 . Ticket service center 110 may receive orders from sales merchant 120 to create new tickets, update existing tickets, or delete existing tickets. When authorized by sales merchant 120 , ticket service center 110 may offer tickets for sale to consumers over the Internet (not shown). Alternatively, other methods known in the art may also be used to offer tickets for sale to consumers. Ticket service center 110 may sell tickets to consumers over the Internet, as well as via other avenues known in the art. As part of its ticket selling task, ticket service center 110 may associate a consumer's PID 150 with a newly-purchased ticket. If a purchasing consumer does not yet possess a PID 150 , ticket service center 110 may first issue a new PID 150 to that consumer. As tickets are sold, ticket service center 110 may execute and record ticket sales transactions in its database. When a consumer presents a PID 150 to redeem a previously-issued ticket, the consumer—or someone on the consumer's behalf—may insert PID 150 into ticket authenticator 130 for authentication. Ticket authenticator 130 may then transmit an authenticated ticket request message to ticket service center 110 . When ticket service center 110 receives the authenticated ticket request message, ticket service center 110 may execute and record a ticket redemption transaction, and return to ticket authenticator 130 a ticket redemption message directing ticket authenticator 130 either to authenticate or reject the ticket redemption request. Upon request by sales merchant 120 , ticket service center 110 may reconcile ticket sales transactions and ticket redemption transactions, and may issue various reports to the sales merchant 120 . In each of these tasks, ticket service center 110 may update its central database to reflect the new state of the transaction made.
[0024] Continuing to refer to FIG. 1, ticket service center 110 may include a collection of distributed processors, some of which may be redundant. Some redundant processors may enable portions of the ticket service center 110 to communicate more efficiently with other components of the system. Other redundant processors may function as backup units that come on-line when a processor fails or requires maintenance. Still other redundant processors may simply provide added computational power at peak demand periods, such as when many tickets are being redeemed at a scheduled event.
[0025] As part of its ticket sales task, ticket service center 110 may advertise tickets for sale using any number of advertising techniques known in the art. Ticket service center 110 may also cooperate with auctioning systems, such as eBay, to assist in the transfer of a previously-sold ticket from one consumer to another. Furthermore, ticket service center 110 may provide ticket trading and exchange services directly. Whenever ticket service center 110 transfers a previously-acquired ticket from one consumer to another, it may disassociate a first consumer's PID 150 from a ticket, and then associate a second consumer's PID 150 with that same ticket.
[0026] Ticket purchases may occur through an Internet web interface, although ticket purchases are certainly not limited to this medium. During a purchase, a consumer may present a previously-issued PID 150 account number and password, and pay for the ticket. In the ticket service center 110 database, the purchased ticket is associated with the consumer's account number. The purchased ticket is also associated with a public key corresponding to the consumer's PID 150 . After a ticket is sold, it is then marked “sold” in the database.
[0027] Additionally, the term “purchase,” as used herein is intended to include the acquisition of a ticket without the transfer of money. That is, the price of a ticket may be zero ($0.00).
[0028] Sales Merchant 120
[0029] As further illustrated in FIG. 1, sales merchant 120 may post tickets for sale with the ticket service center 110 . This transaction is called a vendor post. As alluded to previously, a vendor post is simply a process whereby a ticket or groups of tickets are made available for sale. To affect a vendor post, sales merchant 120 may negotiate with ticket service center 110 the right to sell a ticket. This negotiation is accomplished, in part, by sales merchant 120 submitting to ticket service center 110 all the necessary details for the ticket. These details may include price, seat number, redemption date, redemption time, and venue merchant. A ticket posting may be accomplished interactively, ticket by ticket. A ticket posting may also be accomplished in groups, wherein aggregate data describing collections of tickets are transmitted to ticket service center 110 . When ticket service center 110 accepts a vendor post, it transmits a vendor post acknowledgement signal to sales merchant 120 .
[0030] As will be appreciated by one of skill in the art, sales merchant 120 and venue merchant 140 may be the same entity in actual fact.
[0031] Sales merchant 120 may elect to withdraw a vendor post by instructing ticket service center 110 to remove a specific ticket (or group of tickets) from the ticket service center 110 database of active tickets. A removed ticket need not be purged from the ticket service center 110 database. Instead, a removed ticket may be simply marked as “inactive.”
[0032] A ticket post may also be made by a consumer who wishes to resell a ticket. This is a different kind of ticket post that does not create a new ticket, but instead may change the state of an existing ticket from “sold” to “for resale.”
[0033] After sales merchant 120 completes a vendor post, sales merchant 120 informs ticket service center 110 about all the possible ticket authenticators 130 that may be granted permission to redeem the posted tickets. Sales merchant 120 may also inform ticket service center 110 about certain conditions under which tickets may be redeemed. For example, sales merchant 120 may authorize ten specific ticket authenticators 130 to redeem tickets for a designated event in a particular window of time. In this example, the event description might include a unique event identifier created and registered by sales merchant 120 . Once the unique event identifier is associated with the appropriate ticket authenticators 130 and the appropriate tickets, if sales merchant 120 requires changes to be made to the event, sales merchant 120 could use this unique event identifier to communicate the appropriate changes to ticket service center 110 .
[0034] Ticket authenticator 130 may close an event by sending sales merchant 120 a list of all the ticket redemptions made for a given event. Sales merchant 120 may then collate this list of all the ticket redemptions with similar lists sent to sales merchant 120 by other ticket authenticators 130 governing the event.
[0035] After collating all the ticket transactions for an event, sales merchant 120 may reconcile received ticket redemptions with ticket service center 110 . By reconciling the data received from ticket authenticators 130 and similar data received from ticket service center 110 , sales merchant 120 protects itself from error or fraud by identifying any uncorroborated ticket redemption transactions.
[0036] PID 150
[0037] [0037]FIG. 2 is a representative drawing of PID 150 , according to an embodiment. Referring now to FIG. 2, each consumer may possess a PID 150 (see also FIG. 1). PID 150 may include a digital signature key set, which is used to authenticate ticket purchases. The key set includes a private signing key 250 used for signing a transaction, and another public verifying key 260 for verifying the signature. Signing key 250 is unique to each PID 150 and is not externally accessible. However, verifying key 260 is made publicly available. Verifying key 260 is commonly referred to as a public key, and it is stored at ticket service center 110 (FIG. 1) with its associated consumer account.
[0038] Of course, one kind of PID 150 may differ in its capabilities from other kinds of portable information devices. Therefore, one PID 150 may be more suitable for one or more embodiments of the present invention, but not as suitable for other embodiments.
[0039] Ticket Authenticator 130
[0040] Referring again to FIG. 1, ticket authenticator 130 is a processing device, such as a computer, which may have a display, a PID terminal, a printer, and network connectivity. The primary function of ticket authenticator 130 is ticket redemption. However, ticket authenticator 130 may also communicate with sales merchant 120 to reconcile ticket redemptions.
[0041] According to an embodiment, to redeem a ticket, a consumer first engages his/her PID 150 with the ticket authenticator 130 . Ticket authenticator 130 then creates and signs a ticket request message, and transmits this ticket request message to the consumer's PID 150 . A ticket request message may contain the following elements:
Ticket Request Message Event Identifier (e.g. Movie name) Time and Date Ticket Authenticator Public Key Ticket Authenticator Digital Signature
[0042] In return, ticket authenticator 130 receives an authenticated ticket request message from the consumer's PID 150 . At this stage, the authenticated ticket request message has been dually authenticated with the signing key of ticket authenticator 130 as well as the signing key 250 of the consumer's PID 150 . An authenticated ticket request message may contain the following elements:
Authenticated Ticket Request Message Event Identifier (e.g. Movie name) Time and Date Ticket Authenticator Public Key Ticket Authenticator Digital Signature PID 150 Public Key PID 150 Digital Signature
[0043] After ticket authenticator 130 receives an authenticated ticket request message from PID 150 , it sends the dually authenticated ticket request to the ticket service center 110 . According to an embodiment, ticket service center 110 may perform a series of validation tests to determine whether the authenticated ticket request message is valid. If any of the validation steps fail, ticket service center 110 may deny the authenticated ticket request. Validation tests may include the following: Is the ticket authenticator 130 public key valid? Is the PID 150 public key valid? Is the ticket authenticator 130 digital signature valid? Is the PID 150 digital signature valid? Are the date and time fields valid? Is this ticket authenticator 130 authorized to redeem a ticket for this event?
[0044] If ticket service center 110 determines that the authenticated ticket request message is valid, ticket service center 110 may respond with a ticket redemption message. A ticket redemption message may contain the following elements:
Ticket Redemption Message Authenticated Ticket Request Packet Ticket Contents (Names, Seating, etc . . . ) Transaction Number Transaction Time ticket service center 110 Digital Signature1 ticket service center 110 Digital Signature2
[0045] Once a ticket has been redeemed by ticket service center 110 , ticket authenticator 130 may validate the ticket redemption message and then may print a receipt for the consumer, which may include seating, price, and other ticket information. The ticket redemption message may be recorded at both ticket authenticator 130 and the ticket service center 110 .
[0046] Ticket authenticator 130 may close an event by sending sales merchant 120 a list of all the ticket redemption messages received for the event. Sales merchant 120 may collate these transactions with other ticket authenticator 130 operating at the event.
[0047] Venue Merchant 140
[0048] Continuing to refer to FIG. 1, venue merchant 140 may grant consumers access to an event, or may otherwise admit attendees having authenticated tickets.
[0049] Venue merchant 140 may sell tickets. To do so, venue merchant 140 may issue PID 150 cards to consumers. When venue merchant 140 performs this ticket-selling function, it may coordinate its ticket selling activities with ticket service center 110 .
[0050] Venue merchant 140 may also interact with sales merchant 120 to coordinate ticket redemption. Prior to a ticket redemption event, or whenever a ticket redemption process is appropriate, venue merchant 140 may initiate operation of the necessary ticket authenticators 130 , may communicate event status to ticket service center 110 , and may perform other event-related and venue-related functions.
[0051] Ticketing System 100
[0052] According to an embodiment, ticketing system 100 may provide access to concessions within an event. A ticket may include financial information, which may be accessed and debited as a result of a consumer-initiated purchase using PID 150 at an appropriate event.
[0053] According to another embodiment, ticketing system 100 may provide purchasing authorization to members of a club, where a purchased ticket corresponds to a set of purchasing permissions, including spending limits and credit authorizations.
[0054] According to still another embodiment, ticketing system 100 may provide identity authentication for applications such as driver's licenses, VISAs, and passports.
[0055] According to still another embodiment, ticketing system 100 may provide identity authentication as well as spending authorization for meal plans and school payment systems.
[0056] According to still another embodiment, ticketing system 100 may be used to authenticate transactions where pictures, biometric information, and other personal identification information may be provided either by PID 150 itself or by another device used in combination with PID 150 .
[0057] Several embodiments of the present invention are specifically illustrated and described herein. However, it will be appreciated that modifications and variations of the present invention are covered by the above teachings and within the purview of the appended claims without departing from the spirit and intended scope of the invention. Other logic may also be provided as part of the ticket redemption process but are left out here so as not to obfuscate the present invention. | A system and method for purchasing, issuing and redeeming electronic tickets using portable information device (“PID”) technology. Utilizing the accessibility, convenience, and fraud protection features of PIDs, embodiments of the present invention store identification information on a user's PID, and then, utilizing a ticket server and an authentication device, provide mechanisms to access the PID in order to authenticate and/or validate the user. | 6 |
BACKGROUND
The invention relates to a method for processing an elastomer, an elastomer made by said method, and tires made using the elastomer.
Prior art composites used in the tire industry comprise rubber compositions, for example composites based on styrene butadiene rubber (SBR), polyisoprene, polybutadiene, polychloroprene, nitrile butadiene rubber (NBR), ethylene propylene diene monomer rubber (EPDM), natural rubber and mixtures thereof.
It is continually a goal in the tire art to provide rubber compounds that enhance traction properties while providing good rolling resistance properties and good wear properties.
As described by Novon Products, a Division of Warner-Lambert Company, 182 Tabor Road, Morris Plains, N.J., starch consists of two types of glucose polymers, linear amylose and branched amylopectin. The distribution of these two polymers affects the properties of the starch. Although starch in dry form is not thermoplastic, it forms a melt in the presence of a plasticizer such as water. The large number of hydroxyl groups in the starch molecule import a B hydrophilic character to the molecule that limits its applicability in the preparation of plastic substitutes based on native starch, but to increase the range of viable applications of starch based plastics in product use, native starches can be blended with degradable synthetics. Since the goal of Novon is to improve the environment by producing biodegradable plastics, Novon notes that when other degradable polymers are blended with starch, or the starch is modified to improve properties or processability, the rate of biodegradation will change, and the challenge of developing starch-based plastic substitutes is to improve the properties while maintaining acceptable degradation rates, and quantification of biodegradation rates in wastewater, soil, and compost environments is an important part of the product development process.
Starch materials have been used as model systems in investigations of physical and engineering properties of foods. Isothermal absorption of water in starch gels gave low water diffusivities which decreased at lower moisture contents (Fish 1958).
Destructured starch compositions that have dimensional stability and hydrophilic properties have been described by Warner-Lambert in EPA 409,789, EPA 409,788, EPA 404,728, EPA 404,727, EPA 404,723 and U.S. patent application Ser. No. 467,892 filed Feb. 18, 1983.
It is believed that similar compositions are produced by Archer-Daniels-Midland.
In accordance with the present invention, the inventors herein have theorized that the hydrophilic properties of the starch based polymers, when used in a tire tread, will provide enhanced traction on wet pavement, because of the wettability of the polymer, while providing good rolling resistance properties on dry pavement.
Accordingly, it is an object of the present invention to provide a method by which the properties of a rubber composite can be optimized for a particular use by adjusting the amount of hydrophilic polymers, and conventional reinforcing fillers (such as carbon black, silica, etc.) in the composite.
SUMMARY OF THE INVENTION
A method of processing hydrophilic polymers into an elastomer is provided. The method comprises blending a 1-33% by weight hydrophilic polymer, based on the total weight of the composition, with a base elastomer.
In one embodiment, the hydrophilic polymer will be chosen to have properties whereby the hydrophilic polymer retains its identity while mixing with the base polymer, and forms fibers in-situ in the polymer blend. The orientation of the fibers may be controlled by processing.
Also provided is an elastomer comprising a base elastomer and a hydrophilic polymer. In one embodiment, the hydrophilic polymer will be present in the elastomer in the form of fibers dispersed in the elastomer. Also provided is a pneumatic tire made using the elastomer of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a pneumatic tire made using the elastomer of the invention, and the various parts thereof which may contain the elastomer.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to a method of processing elastomer with hydrophilic elastomers and elastomers produced by said method. In particular, the invention relates to elastomer which are reinforced by hydrophilic polymers.
Starch can be used to form hydrophilic, thermoplastic polymers having a melting temperature that depends on the mixing condition of the starch material.
Elastomers such as polyisoprene rubber, styrene butadiene rubber (SBR), polybutadiene rubber, nitrile butadiene rubber (NBR), polychloroprene rubber, natural rubber, EPDM (ethylene propylene diene monomer rubbers), and mixtures thereof, can be mixed with a hydrophilic polymer at conventional compounding temperatures when chemically preparing the hydrophilic polymer in-situ, or at a temperature above the melting point of the polymer when a thermoplastic starch polymer is used to melt form the hydrophilic polymer. It has been found in accordance with the present invention that the hydrophilic polymer may comprise 1-50%, preferably 10-40%, and most preferably 15-30% of a resulting base-polymer/hydrophilic-polymer blend.
Examples of hydrophilic polymers which may be used to provide the elastomers of the invention include polymers based on starches. Examples of such polymers are derived from linear amylose, branched amylopectin, and mixtures thereof. In one embodiment, such polymers have the ability to retain their own identity when being mixed with the base elastomer, and accordingly are mixable with the base elastomer while not being miscible, and accordingly, are capable of forming fibers in the matrix of the base elastomer.
The source of such hydrophilic polymers is described in the Background above.
Although it is preferred that the hydrophilic polymer form fibers in the elastomer, those skilled in the art will recognize that homogeneous blends of a base elastomer and a hydrophilic polymer can also be made and used in accordance with the invention.
Optionally 0-3% by weight grafting agent may be added to the elastomer to provide polymeric compatiblizing and potential linking between the base elastomer and the hydrophilic polymer.
With reference now to FIG. 1, a pneumatic tire 30 which is made using the hydrophilic elastomer of the invention is illustrated. It is believed that the hydrophilic elastomer made according to the invention may be used most beneficially in the tread cap of a pneumatic tire. In the illustrated embodiment, tire 30 comprises a pair of beads 32, carcass plies 34 wrapped around beads 32, belts or breakers 36 disposed over carcass plies 34 in the crown area, tread cap 38 disposed over tread base 42 and belts or breakers 36, and sidewalls 40 disposed between tread cap 38 and beads 32.
Since the hydrophilic polymer has low water diffusivities, the hydrophilic property of the elastomer in wet conditions will be most apparent on the surface of the tread. As is known in the art, as the moisture content of a hydrophilic polymer is increased, there is a decrease in the glass transition (Tg) of the polymer. In wet conditions, the hydrophilic polymer absorbs water, and the properties of the polymer at the tread surface change, in proportion to the amount of water absorbed, to provide a softer, more tactile tread surface, thus improving traction.
As the moisture content of the polymer increases above about 22%, the Tg of starch based materials approach the Tg observed at temperatures below room temperature.
Particular hydrophilic polymers contemplated for use in the invention can have a Tg which varies from about 150° C. to about 0° C., depending on its moisture content. It is believed that such polymers available from Warner-Lambert, having a Tg which varies from about 120° C. to 20° C. can be used.
By understanding the changing properties of the hydrophilic polymer, and by fine tuning the tread composite using other additives known to those skilled in the art, a tread rubber composition having high loss (high hysteresis) properties, which directly relates to high traction, in moist conditions, made according to the invention, is possible.
The change in Tg observed in the polymer is reversible, and in dry conditions, the elastomer retains a more conventional matrix structure, is stiffer, and maintains good rolling resistance properties.
Accordingly, the tire of the invention adapts to have specific properties that are most desirable for the specific weather conditions it encounters.
In the method of preparing the hydrophilic polymers of the invention, any conventional mixing equipment known in the art may be used to mix the elastomer/hydrophilic-polymer mixture, including Banbury® mixers, extruders, and twin screw extruders. The specific properties of the elastomer can be controlled by obtaining specific data on the properties of the specific hydrophilic polymer used, and controlling the amount of the hydrophilic polymer that is used in the elastomer.
About 1 phr to 33 phr hydrophilic polymer (1-50% by weight) in the hydrophilic polymer blend, provides a good range between polymer blends that have good adhesion and low hydrophilic properties, and polymer blends that have high hydrophilic properties.
As is known in the fiber composite processing art, the orientation of fibers and microfibers in a composite can be controlled by the choice of the mixing equipment that is used to mix the composite, and the manner in which equipment is used. Accordingly, when the hydrophilic polymer is in the form of fibers, the orientation of the fibers in the elastomer can be controlled.
A starch derived hydrophilic polymer may be based on amylose, amylopectin, and mixtures thereof, as illustrated by the above named Warner-Lambert patent applications.
Those skilled in the art will recognize that the hydrophilic nature of the polymer used in the elastomer, over time, may enhance the biodegradability of a tire made using said polymer.
While specific embodiments of the invention have been illustrated and described, those skilled in the art will recognize that the invention can be variously modified and practiced without departing from the spirit of the invention. The scope of the invention is limited only by the following claims. | A method of blending a hydrophilic polymer into an elastomer matrix, and products made thereby, are provided. In the illustrated method, a hydrophilic polymer is mixed with an elastomeric base polymer. In one embodiment, the hydrophilic polymer forms fibers in a resulting elastomeric matrix. An elastomeric matrix interspersed with hydrophilic polymer made according to the invention can be used in reinforced elastomeric products such as tires. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a dryer for drying delicate garments which are subject to shrinkage. Specifically a drying cycle controller is disclosed for a dryer which will dry the garment in an environment of controlled temperature and humidity.
Various devices have been proposed to control the drying of garments so that minimum wrinklage, or shrinkage of the garments occur. Included among such devices is a device described in U.S. Pat. No. 5,161,314 for controlling the drying of tumbled material. The device of the foregoing patent reduces wrinklage of the garments by controlling the drying temperature profile in the tumbling chamber during a cool down cycle which follows a drying cycle. As disclosed in the aforesaid patent, the wrinklage of the dried material is reduced if a preferred temperature versus time profile is maintained during a cool down cycle rather than permitting the temperature to decrease at a naturally occurring exponential rate.
Although the foregoing device reduces wrinklage, there are many garments which are dry cleaned only as they are prone to excessive shrinkage if moisture is removed from the garment too rapidly. The rate of water removed varies for different types of garments and is highly dependent upon the material type as well as the load size.
The rate of moisture removal and the shrinkage and wrinklage which occurs in dry clean only garments depends upon the size of the load being dried, the material type, and the relative humidity of the external environment. Unless the drying environment is controlled to take into account each of these factors, the rate of moisture removal can not be adequately controlled to avoid wrinklage and/or shrinkage of the garment.
SUMMARY OF THE INVENTION
It is object of this invention to control the rate of drying of material being tumbled in a garment dryer.
It is a more specific object of this invention to provide a drying cycle controller for controlling the temperature and humidity within a drying chamber of a garment dryer during a drying cycle.
These and other objects of the invention are provided by a drying cycle controller which includes a processor connected to a temperature sensor and a humidity sensor for deriving a burner control signal. The control signal establishes a desirable drying chamber temperature versus time profile which accurately controls the rate at which moisture is removed from the tumbled material.
In a preferred embodiment of the invention, the processor is programmed to establish an initial drying temperature for materials being tumbled in a drying chamber. Once the initial drying temperature is established, the tumbled materials are permitted to dry until a preset reduction in relative humidity within the drying chamber is achieved. The drying temperature is then reduced step wise to a new drying temperature. Additional step wise decreases in the drying temperature may be effected each time a new predetermined level of relative humidity is achieved within the drying chamber. The rate of moisture removal can therefore be accurately controlled to reduce wrinkling and/or shrinking of the material.
A set of tables is provided which includes a series of drying temperature settings, and corresponding relative humidity setting representing drying stages of different drying cycles for different garment types, as well as the size of a load of material being tumbled. The user may select a drying cycle for the controller based on these considerations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a garment dryer having a controller for controlling the rate of moisture removal from garments being dried.
FIG. 2 illustrates the conventional temperature and humidity profile of the drying chamber environment during a prior art drying cycle.
FIG. 3 illustrates the relationship between temperature and humidity of a drying chamber during a drying process in accordance with one embodiment of the invention.
FIG. 4 is a flow chart illustrating the initial steps carried out by the electronic controller to enter an initial drying phase.
FIG. 5 illustrates the steps executed by the electronic controller to generate a preferred humidity versus temperature profile during an initial drying phase.
FIG. 6 illustrates the steps executed by the electronic controller during a mid-cycle drying phase.
FIG. 7 is a flow chart illustrating the steps performed by the electronic controller 13 during the end phase of the drying cycle.
FIG. 8 is a flow chart illustrating the conclusion of a cool down cycle.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 there is shown an implementation of the invention in accordance with the preferred embodiment. The invention is directed to a drying apparatus having a drying chamber 1, which includes a rotating perforated drum 3. Material to be dried are loaded into the perforated drum 3, and rotated by a motor 25 to tumble the material during drying.
Hot drying air is introduced into the drying chamber 1 by an inlet 5 connected to a burner 7. A blower 11 coupled to motor 25 draws ambient air into the inlet 5, where it is heated by a burner 7 before entering the drying chamber. Control over the tumble motor 25, and blower 11 results from the tumble motor control 27 being enabled during a drying cycle by electronic controller 13. The burner 7 is shown as a gas operated burner, receiving a source of fuel through gas line 33 under control of a solenoid valve 21.
Control over the drying temperature is achieved with a burner control circuit 23 similar to the apparatus described in U.S. Pat. Nos. 5,161,314, and 4,827,627. A closed loop control system comprising a temperature sensor 35, electronic controller 13, and burner control circuit 23, maintains the inlet 5 air temperature substantially constant.
A first humidity sensor 36 is located in the exhaust outlet 9 of the drying chamber 1, and a second humidity sensor 34 is located at the inlet of burner 7, for sensing the room environment relative humidity.
The system of FIG. 1 includes a keyboard 29 and display 31. The keyboard 29 permits the entry of various parameters for controlling drying, as well as the programming of the electronic controller 13 to execute the steps comprising a drying cycle as will be described later herein. A power supply 19 is connected to the line voltage for providing operating voltage to electronic controller 13.
The control over the drying cycle will be explained with respect to FIGS. 2 and 3. FIG. 2 represents temperature and humidity conditions within the drying chamber 1 in accordance the prior art drying cycle. In the prior art an initial drying temperature is reached throughout the drying cycle and is maintained at a constant temperature T0. As shown in FIG. 2 the humidity within the drying chamber 1 undergoes a rapid decrease, while drying at a constant temperature, producing a rapid removal of moisture inducing shrinkage and/or wrinklage to the garments being dried.
FIG. 3 represents a temperature and humidity profile for the drying chamber 11 in accordance with the preferred embodiment of the invention. The temperature profile is shown as a stepped temperature profile, which increases the drying time, and avoids a steep drop in the relative humidity within the drying chamber 1, and the corresponding rapid reduction in moisture which occurred in the drying cycle depicted in FIG. 2. The three temperatures constituting a drying cycle comprise a high temperature, mid-cycle temperature, and end cycle temperature.
In order to achieve the temperature and humidity profile during the drying cycle in accordance with FIG. 3, the tumbled garments are dried at three separate temperatures, with the initial drying temperature being the highest. Control over drying temperature is effected based on the sensed humidity conditions within the drying chamber. The drying temperature is lowered from an initial high temperature setting to a midcycle temperature setting when the humidity within the drying chamber i is equal to a humidity level representing a temperature switch point. As shown in FIG. 3, there are three humidity conditions, R HI, RH MID, and/or RH LOW which result in the drying temperature being changed from T HI to T MID, and then to T LO. The last relative humidity condition RH LO results in the burner being disabled ending the drying cycle.
In accordance with a preferred embodiment, Table 1 shows for different materials being dried, i.e., a suit or a coat, and for three different load sizes, three temperatures T HI, T MID and T LO as well as relative humidity levels R HI, R MID and R LO for defining drying conditions for the material in a controlled drying cycle.
TABLE 1______________________________________CYCLE LOAD TEMPERATURES RELATIVE HUMIDITYTYPE SIZE T HI T MID T LO R HI R MID R LO______________________________________SUIT LARGE 160 145 130 28% 23% 22% MEDIUM 160 145 130 25% 22% 21% SMALL 160 145 130 22% 18% 17%COAT LARGE 160 145 135 28% 23% 21% MEDIUM 160 145 135 25% 21% 19% SMALL 160 145 135 22% 18% 16%______________________________________
Table 1 illustrates that drying is effected by the size of the load as well as the type of garment being dried. The values in the table are also dependent on the relative humidity of the room containing the dryer. Table 1 is a fairly typical representation of drying cycle conditions when room relative humidity is 45%.
Table 2 illustrates the effect of environmental relative humidity on each of the drying chamber relative humidity steps R HI and R MID of Table 1 for a given load size. Each of the relative humidity settings of Table 1 can be weighted, in accordance with the load size as follows: Large=100%, Medium=95%, and Small=90%.
TABLE 2______________________________________ (R.sub.-- HI) (R MID)ROOM R.H. 1ST R.H. STEP 2ND R.H. STEP______________________________________0 (ERROR)1-3% (ROOM)-1 (R.sub.-- HI)-14-8% (ROOM)-1 (R.sub.-- HI)-1 9-13% -3 -214-18% -5 -219-23% -6 -324-28% -7 -329-33% -9 -434-38% -11 -439-43% -13 -544-48% -17 -549-53% -19 -654-58% -21 -659-63% -24 -764-68% -26 -769-73% -28 -874-78% -30 -879-83% -32 -984-88% -34 -989-93% -36 -1094-98% -38 -10 99% -40 -11100% (ERROR______________________________________
FIGS. 4, 5, 6, 7 and 8 illustrate more completely the programming steps executed by electronic controller 13 to derive a drying cycle in accordance with the preferred embodiment of the present invention. The flow chart represented in FIGS. 4, 5, 6, 7 and 8 illustrates a control sequence for the burner 7 of FIG. 1 to generate a decreasing temperature profile from a sensed humidity condition within drying chamber 1.
The program starts at 50, when a load of material to be dried is loaded in the tumbler 3 of the drying chamber 1. The start command is entered through the keyboard 29 of the electronic controller. A 32 minute timer is activated in step 51 as a maximum time safeguard against over drying. In the event the electronic controller 13 has not completed the drying cycle within 32 minutes, the drying cycle will be terminated. The blower 11 and motor 25 are activated in step 52 to begin the drying process.
The display 31 displays a material type entered through keyboard 29 being dried within the drying chamber 1. Further, the load size (also entered through keyboard 29) which as noted previously is a parameter in determining the humidity level for stepping down the drying temperatures, is also displayed alternatively with the material type.
A stabilization period is entered in step 54, by initiating a second timeout period for 20 seconds. During the 20 second period, the sensor conditions are permitted to settle. Following the 20 second timeout period, decision block 56 will enable the electronic controller 13 to measure and store the relative humidity sensed by sensor 34.
Having now determined the relative humidity, it is possible to determine the first and second temperature switch points from a table containing data such as is shown in Tables 1 and 2. The initial RH switch point and mid-cycle RH switch point are determined based on the room relative humidity and the load size being dried. The end of the cycle switch point R LO is obtained from Table 1 based on the fabric type and is substantially invariable to load size.
With the conditions set for defining the drying cycle, the burner controller circuit 23 is activated in step 59, and the temperature of the drying chamber 1 is increased to the high temperature value T HI. The elapsed time after reaching T HI is continuously displayed on display 31. Once the initial high temperature T HI has been reached within drying chamber 11 as determined in step 63, the temperature is maintained by the electronic controller 13 as represented in step 64. As set forth in the previous patents, the temperature is maintained constant by the feedback loop constituting controller 13, temperature sensor 15 and burner 7.
During the time the drying temperature is at the initial high temperature level T HI, the relative humidity monitored by the sensor 36 is continuously measured. When the initial relative humidity R HI set point is reached in 65, a change in drying temperature occurs.
Electronic controller 13 in accordance with step 66 will let the drying temperature decrease to the new operating temperature T MID for the drying chamber 1. Decision block 68 determines whether the temperature is below the new, mid-cycle temperature set point T MID in decision block 68. The electronic controller 13 will maintain the temperature as sensed by temperature sensor 35 to the selected setting T MID in step 69.
The relative humidity during the mid-cycle temperature setting T MID is continuously measured, and when the mid-cycle relative humidity RH MID is detected in step 70, the operating drying chamber 1 temperature will then be reset to the final end of drying cycle temperature setting T LO. The transition from mid-cycle temperature setting to T MID end of cycle temperature T LO occurs at any time the relative humidity setting as determined in step 70 reaches the predefined limit. Steps 71 and 72 continuously measure the drying temperature and maintain the drying temperature at T MID until RH LO has been detected in the drying chamber.
Once the mid-cycle relative humidity has been obtained, as determined in decision 74, the operating temperature is set to the final operating temperature T LO in step 75. Decision blocks 76 through 80 will determine whether or not the final temperature has been reached, and activate the heat in step 80 as necessary to reach the final temperature.
Once the final relative humidity within the drying chamber 1 has been found to equal the final relative humidity RH LO in decision block 81, heating is discontinued in step 86 and a cool down time cycle for the dryer is entered. Until the final end of cycle relative humidity setting has been detected, the temperature is continuously monitored in step 82 and maintained by step 83 at the final temperature T LO setting. Decision block 84 participates in the process of activating the heat in step 80, whenever the temperature falls below the end of cycle final temperature T LO. Decision block 85 determines, after maintaining the temperature of the drying chamber at the final end of drying cycle temperature for a period of time, when the relative humidity within the drying chamber has reached the final end of cycle relative humidity RH LO set point.
The cool down cycle is entered in step 86, and the display 31 will indicate the cool down time 88. The cool down cycle can be set for a specific timed period, which is constantly measured. Once the cool down time has expired as determined in decision block 89, the motor 25 is deenergized, as well as blower 11 to step 90 by the electronic controller 13. The display 31 indicates that drying is done in 91.
An air jet solenoid, is associated with the humidity sensor 36. At the completion of a drying and cool down cycle, the air jet solenoid may be activated by the electronic controller 13 to clean any lint accumulation occurring on the humidity sensor 36 in step 92.
Once the door to the drying chamber 1 is opened, the electronic controller 13 is reset back to an initial condition in step 93. A fill indication is displayed on display 31 indicating the dryer is ready for an additional load. The process is therefore completed 95.
Thus there has been described with respect to one embodiment of the invention a complete programming sequence for an electronic controller for providing a drying cycle which minimizes shrinkage and wrinklage of delicate garments. Those skilled in the art will recognize yet other embodiments described more particularly by the claims which follow. | A drying cycle controller for a garment dryer. The drying cycle is controlled to have a decreasing temperature and humidity profile which avoids the removal of moisture at a rate which will cause shrinkage and wrinkling of the garment. The drying cycle temperature profile is controlled by continuously sensing the humidity within the drying chamber, and decreasing the drying temperature each time the relative humidity drops to one of a plurality of set points. Once the humidity has reached the final set point, the dryer enters a cool down cycle for a predetermined cool down time. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit under 35 U.S.C. §119(a) of German Patent Application No. 10 2009 024 826.9-32, filed Jun. 13, 2009, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates generally to a system for compensating electromagnetic interfering fields, and in particular to a system for magnetic field compensation having two sensors and a digital processor.
[0004] 2. Description of Related Art
[0005] For compensating electromagnetic interfering fields, in particular magnetic interfering fields, feedback control systems are used in the very most cases, whereby one, or more sensors measure the amplitude of the interfering field for all three Cartesian space axes. The measuring signals of the sensors are fed to a control loop, which calculates control, or actuator signals from the measuring signals of the sensors, for devices generating magnetic fields.
[0006] The magnetic field to be compensated may be the terrestrial magnetic field, or may be generated by other current-carrying devices being in the surrounding.
[0007] Magnetic field compensation systems are for example used in connection with imaging systems using magnetic fields, for example in the case of scanning electron microscopes (SEM).
[0008] In case of the mentioned devices for generating magnetic fields, it may be a matter of a current-carrying conductor, in the easiest case. Generally, one assumes interfering fields having far field characteristics, i.e. such fields, whose field amplitude does not essentially change within the range of 5 m. This assumption for example is true for interferences by rail vehicles. If the interfering fields are homogeneous in the range of interest, the compensation fields should be homogeneous, also.
[0009] Pairs of so-called Helmholtz coils are preferably used for generating homogeneous compensation fields. At this, it is about two coils each being connected in the same direction, and having a distance to each other being equal to the half length of the edge (=coil diameter) (so-called Helmholtz condition).
[0010] Furthermore, pairs of Helmholtz coils are used, whose distance to each other is equal to one length of the edge. If one pair of Helmholtz coils is used for each of the three space axes, the pairs of coils form a cube-shaped cage around the location, at which one, or more interfering fields shall be compensated. In case of such a coil arrangement, there indeed are field inhomogeneities in the interior of the cage, but these are acceptable in the most cases of application.
[0011] A device for compensating magnetic fields is disclosed in U.S. Publication No 2005/019555A1 and has three coil pairs in a cage. The magnetic field to be compensated is measured and compensated, where an analog controller is used.
[0012] Systems are also available, with which only one coil per space axis is used for generating the compensation field, however the compensation region, i.e. the region in which a good compensation is achieved, is considerably smaller than in the case of Helmholtz coils.
[0013] Generally, one single magnetic field sensor is used for measuring the magnetic field at the place of interest. As an exception, there is a second sensor which is, however, used for diagnosis purposes. A single magnetic field sensor does not allow to detect, whether the magnetic field to be compensated is homogeneous, or inhomogeneous at the location of the object to be protected.
[0014] It is a further problem when compensating electromagnetic interfering fields that it cannot be measured directly at the location at which the interfering field is to be compensated, since the object to be protected against interfering fields generally is at this location.
[0015] A further problem arises, if two magnetic field compensation systems are arranged directly adjacent to one another. Then, undesired feedback effects may occur between the two systems.
[0016] There are problems with the control systems in that these control systems can generally be optimized to single application. An adjustment to control tasks that are quite different, such as upon changes in the control configuration, is as a rule not possible or only in a restricted manner possible and/or is to be implemented with great difficulties. Furthermore non-linear control systems which may have a better interference field compensation than linear control systems, generally can only be implemented with high costs. When control circumstances change, the whole control circuit or the control loop would have to be newly calculated, designed and/or changed. In most cases, the direct user is not a position to do so.
SUMMARY OF THE INVENTION
[0017] Therefore, it is an object of the invention to provide a system for compensating electromagnetic interfering fields with which system homogeneous as well as inhomogeneous magnetic fields may be compensated.
[0018] It is a further object of the invention to perform a simulation of measuring electromagnetic interfering fields at the location of the object to be protected.
[0019] It is a still further object of the invention to equalize potentially arising feedback effects in the case of using two magnetic field compensation systems in immediate vicinity.
[0020] In detail, a system for compensating electromagnetic interfering fields is provided, which has two real triaxial magnetic field sensors, three pairs of compensation coils, and one control unit in order to protect an object against influences of an interfering field. It is preferred to design the control unit as a control processor such as a Digital Signal Processor DSP or a field programmable gate array FPGA.
[0021] The six in total output signals of the two real sensors may be combined to three output signals of a virtual sensor, by means of a freely definable kind of averaging. By choosing the averaging algorithm properly, it can be achieved that the output signals of the virtual sensor represent the amplitude of the interfering field at the location of the object to be protected.
[0022] The averaging takes place by means of the control system, which receives the six output signals of the two real magnetic field sensors via six inputs.
[0023] For every sensor, the output signals of the two magnetic field sensors may be represented by a three-dimensional vector. These two vectors may be combined to six-dimensional vector, i.e. a 6×1 matrix. The averaging over the output signals of the two real sensors, i.e. calculating the output signals of the virtual sensor, may be described by a matrix multiplication:
[0000]
V=M·S
V: 6×1 matrix of the output signals of the virtual sensor;
M: 6×6 matrix describing the averaging over the output signals of the real sensors; and
S: 6×1 matrix of the output signals of the virtual sensor.
[0027] The now available output signals (=virtual input signals of the control system) of the virtual sensor are used as an input for independent control loops operating in parallel. These control loops may be broadband, selective concerning a frequency range, or selective concerning a frequency, also. The control loops have control algorithms transforming the virtual input signals V into changed signals {circumflex over (V)}. At this, {circumflex over (V)} is a 6×1 matrix representing the in total six changed input signals of the control system. The control algorithm is described by an operator Ω. There are no limitations concerning the control algorithm being used. Accordingly, the operator Ω may not be a matrix so that nonlinear algorithms may also be used. Therefore, the transition to the modified signals {circumflex over (V)} is described by
[0000] {circumflex over (V)} =Ω( V )
[0028] The matrix {circumflex over (V)} is multiplied by a 6×6 matrix L, in order to obtain control signals for the six coils, i.e.
[0000]
O=L·{circumflex over (V)}
[0000] with:
L: 6×6 matrix for calculating the control signals O from the modified signals O=L·{circumflex over (V)}.
[0029] Therefore, the algorithm used by the control system may overall be described as follows:
[0000] O=L·Ω ( M·S )
[0030] The more inhomogeneous the compensation field is in case of homogeneous interference, and the more homogeneous the compensation field is in case of inhomogeneous interference, the smaller is the region around the feedback sensor having a good compensation effect.
[0031] If the interference field is inhomogeneous, it is not purposeful to generate a homogeneous compensation field. In this case, it is also purposeful to use a single actuator coil instead of a pair of Helmholtz coils.
[0032] Only a single compensation system is used in this case, i.e. only three virtual signals are used for processing virtual sensor positions, and for generating gradient fields so that M may be a 3×6 matrix, and L may be a 6×3 matrix. Alternatively, the “not used” elements of the 6×6 matrices may also be equal to zero.
[0033] In case of a Helmholtz coil arrangement, only one coil of the pair is actively actuated, and that depending on the gradient of the interfering field below the compensation region, or above the compensation region. Therefore, a rearrangement for changing the position of the single coil is not necessary besides a new parametrisation of the control loops, in case of a change of the structure of the interfering field.
[0034] If two compensation systems are operated directly beside each other, this results in mutual interferences. The feedback between the two systems my be described by means of a 6×6 feedback, or crosscoupling matrix C. C represents the feedback of a control signal O i with a virtual signal V i .
[0035] For avoiding interferences, the feedback system will not deliver optimal results. As a rule, an overcompensation, or an under compensation is only feasible for digital control systems, and also in this case for systems not operating in broadband. The position of the sensor would have to be fitted for all other systems. Such a change of position may it make it necessary that the sensors for the three space axes have to be positioned at different positions in space. But because one single system for all kinds of applications is not aimed for, overcompensation or undercompensation respectively is not an appropriate method.
[0036] When doing so, the matrix S of the output signals of the real sensors is enlarged to a 6×1 matrix Ŝ. Therefore, it is true over all:
[0000] O=L·Ω ( M ·( S−C·O ))
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 shows a schematic presentation of the system for compensating an inhomogeneous interfering field;
[0038] FIG. 2 is a schematic presentation of the system for compensating electromagnetic interfering fields, together with its control system,
[0039] FIG. 3 is a block diagram for calculating the control signals of the system for compensating electromagnetic interfering fields,
[0040] FIG. 4 : is a schematic presentation of using the magnetic field compensation system, and
[0041] FIG. 5 : is a schematic presentation of using two magnetic field compensation systems directly besides each other.
DETAILED DESCRIPTION OF THE INVENTION
[0042] In the following, the invention is described in more detail referring to the attached figures by means of exemplary embodiments, wherein same reference signs refer to same components.
[0043] FIG. 1 schematically shows the system for compensating electromagnetic interfering fields. An object 2 to be protected against effects of the interfering field 1 is permeated by the interfering field 1 . Here, the interfering field 1 is assumed to be a gradient field.
[0044] The amplitude of the interfering field 1 is measured by two real magnetic field sensors 3 , and 4 . The first real sensor 3 provides an output signal {right arrow over (S)} 1 =[x 1 (t), y 1 (t), z 1 (t)], and the second real sensor 4 provides an output signal {right arrow over (S)} 2 =[x 2 (t), y 2 (t), z 2 (t)]. These two output signals are fed in a digitised form to the control unit 7 shown in FIG. 2 .
[0045] The control unit 7 has six inputs for the six signals in total, corresponding to 2×3 space axes. Furthermore, the control unit 7 has six outputs for outputting control signals for six coils 6 .
[0046] The two vectors {right arrow over (S)} 1 , and {right arrow over (S)} 2 are combined to a 6-vector S=(S 1 , S 2 , S 3 , S 4 , S 5 , S 6 ). S is processed by the control unit 7 according to the algorithm schematically shown in FIG. 3 . In a first step, the six in total signals fed to the control unit 7 are converted into signals V=(V 1 , V 2 , V 3 , V 4 , V 5 , V 6 ) of a virtual sensor 5 ( FIG. 1 ). This takes place by multiplying S by a 6×6 matrix M. Therefore, it is valid:
[0000]
V=M·S
[0047] The virtual signals V correspond to the amplitude of the interfering field at the location of the object 2 to be protected. Therefore M describes the geometry of the whole arrangement, and how the signals of the two real sensors 3 , and 4 are combined.
[0048] The virtual signals V generated in such a manner are fed to independent control loops operating in parallel, and processed further. These control loops as part of the control unit 7 may be broadband, selective concerning a frequency range, or selective concerning a frequency. The control loops change the virtual signals V to modified signals {circumflex over (V)}. The transition from V to {circumflex over (V)} is described by an operator Ω. Therefore, it applies:
[0000] {circumflex over (V)}=Ω ( V )
[0049] Since there are no limitations concerning the used control algorithms, the modification of the signals V is generally described by the operator Ω, which is not necessarily a matrix so that nonlinear algorithms may be used, also.
[0050] For gaining control signals for the coils 6 , the modified signals {circumflex over (V)} are converted into real control signals O. O again is a 6×1 matrix, therefore containing six single signals, which are used for controlling the six coils 6 . The transition from the modified signals {circumflex over (V)} to the control signals O is therefore described by
[0000]
O=L·{circumflex over (V)}
[0000] or over all:
[0000] O=L ·Ω( M·S )
[0051] Here, L is a 6×6 matrix. The precise values of its elements depend on the nature of the interfering field to be compensated, and on the geometry of the coils 6 generating the compensation field. If, for example, a gradient field acting in x direction shall be compensated, the two coils acting in direction get differently strong signals so that the two coils generate differently high magnetic fields so that the compensation field also is a gradient field, whose direction of field intensity is inverse to the direction of the interfering field.
[0052] The algorithm described up to now is used as long as one single compensation system is only used. For this case, three virtual signals are needed, only. When doing so, virtual sensor positions are calculated, and gradient fields are generated. For this purpose, it is sufficient, if M is a 3×6 matrix, and L is a 6×3 matrix. Alternatively, the “not used” elements of the 6×6 matrices may also be equal to zero.
[0053] Also, two compensation system being placed directly beside each other may be operated by means of the control unit 7 . This can make sense, if two objects to be protected are directly placed beside each other, and shall, or may not be protected by a large compensation system. This implicates that, due to the two compensation systems being used, the regions to be protected have a significantly smaller volume. Therefore, no gradient fields are needed for compensation. With such an installation, generating gradient fields for compensation, however, is also not possible, because the six output signals of the control unit 7 are given to six pairs of coils, which are only able to generate a homogeneous magnetic field in each of the directions in space. The pairs of coils may be connected in series, in parallel, or depending on the impedance. These pairs of coils are each placed around the object 2 to be protected, and each of the corresponding systems is each arranged inside the cage formed by the three pairs of coils each. This configuration is shown in FIG. 4 . Three pairs of Helmholtz coils H 1 , H 2 , H 3 are arranged around the object 2 to be protected. The two real sensors 3 , 4 are inside the one cage H.
[0054] Two compensation systems may also be arranged directly beside each other. This case is shown in FIG. 5 . Here, three pairs of Helmholtz coils H 1 a , H 2 a , H 3 a , or H 1 b , H 2 b , H 3 b respectively each form a cage Ha or Hb, respectively, One of the two real sensors 3 , 4 is in each of the two cages Ha, Hb.
[0055] If two compensation systems are used in direct vicinity, feedback effects may arise between the two systems. This is accounted for by providing a 6×6 back coupling matrix C, which computationally eliminates the parts of the signals, which are crosstalks from an output signal O i to a virtual signal V i . Therefore, C describes the kind of feedback between the two compensation systems installed directly beside each other.
[0056] According to the invention, the 6×1 matrix of the real sensor signals is expanded by the feedback part. If the 6×1 matrix of these expanded signals is denominated by Ŝ, it applies
[0000]
Ŝ=S−C·O
[0057] The 6×1 matrix with the virtual sensor signals is calculated from the signals Ŝ expanded by the feedback part, obtained in this manner. Therefore, it applies:
[0000]
V=M·Ŝ
[0000] finally yielding control signals according to the following relation:
[0000] O=L ·Ω( M ·( S−C·O ))
[0058] In the following, a standard installation of the systems shall be assumed, i.e. only one system is installed. Therefore, no feedback effects occur, which means that the matrix C is equal to the zero matrix. Furthermore, it shall be assumed that the virtual sensor signal in x direction shall be composed of the arithmetic mean of the two real sensor signals in x direction, because the gradient of the interfering field proceeds in x direction. The virtual sensor signal in y direction shall be equal to the signal in y direction of the second real sensor, because, for example, the signal in y direction of the first real sensor contains unwanted components caused by a local interferer. Due to averaging/noise suppression reasons, the virtual sensor signal in z direction shall be equal to the arithmetic mean of the two real sensor signals in z direction. Under these assumptions, the matrix M has the following form:
[0000]
M
=
(
0
,
5
0
0
0
,
5
0
0
0
0
0
0
1
0
0
0
0
,
5
0
0
0
,
5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
)
[0059] If the compensation coils are formed as pairs, and if a homogeneous compensation field shall be emitted in y, and in z direction, which field has a gradient in x direction, the matrix L has the following form:
[0000]
L
=
(
0
,
5
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
0
)
[0060] A double installation is considered in the following example, i.e., two systems for compensating electromagnetic fields are operated directly beside each other.
[0061] Since the output signals for both compensation cages are known inside the control unit 7 in this case, now also feedback parts can be taken into consideration in the control structure. This takes place, as already is described, by using a feedback, or crosscoupling matrix C. This matrix C or its elements, respectively, may experimentally be determined in a comparably easy manner, by applying a signal to an output of the first compensation system, and measuring at the second system, which components are absorbed by the sensors of the second system, and which fraction of the amplitude, in comparison with the sensor of the first system. Then, these signals parts are the elements of the feedback matrix C. When doing so, this measuring method has to be done for all coils.
[0062] If, for example, the output O 5 still radiates onto the sensor input S s with 40%, the matrix element has to be C 25 =0.4. | A system for compensating electromagnetic interfering fields is provided that includes two triaxial magnetic field sensors for outputting real sensor signals; six compensation coils, which are arranged as a cage around an object to be protected, and may individually be actuated; a control unit having six inputs, and six outputs, and a digital processor receiving the sensor signals on the input side, and processing the signals to control signals for the compensation coils. The real sensor signals are converted to virtual sensor signals by a first matrix multiplication for mapping the interfering fields at the location of the object. The virtual sensor signals are made to modified signals by an operator describing the controller structure. The modified signals are converted to real control signals by a second matrix multiplication, which control signals are individually fed to the six compensation coils. | 6 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to a tablet presser put in a tablet bottle to prevent vitamin and drug tablets in the bottle from moving.
[0002] In a tablet bottle, resin film (which is hereinafter referred to as packing) is put in a crumpled state together with tablets. This packing is used to suppress movement of the tablets in the bottle. When the resin film is put in the bottle in a folded state, it swells due to its self-restoring force, so that the effect of pressing the tablets to prevent them from moving is maintained. It is also inexpensive, so that it is often used in tablet bottles.
[0003] A tablet presser other than the packing of resin film is also proposed. As shown in FIG. 7, this existing tablet presser is provided with a shaft 22 at the center of a disk 21 and a knob 23 at the top end of the shaft 22 . The disk 1 is pressed into a tablet bottle to press tablets with it. Since the disk 21 is formed with radial cuts 24 , when squeezed by the mouth of the bottle, it is deformed into the shape of an umbrella, so that its diameter decreases. This makes it possible to push it into and out of the bottle.
[0004] The packing of resin film is not good in appearance. Also, tablets tend to get into gaps and wrinkles formed in the film, so that when the packing is taken out of the bottle, tablets clinging thereto is often taken out together and scatter around.
[0005] On the other hand, since the tablet presser shown in FIG. 7 is three-dimensionally shaped, it is bulky, so that storage, transportation and handling before use are troublesome.
[0006] Also, since it has a shaft and a knob, injection molding is needed, which increases the cost.
[0007] Further, since its shape is complicated, smooth supply and reliable handling with a machine are difficult. Also, there is a difficulty in automatic insertion with a machine. Thus, it is difficult to improve productivity of bottled tablet products.
[0008] An object of this invention is to provide a tablet presser which is inexpensive and not bulky and which can be stacked and automatically put into a bottle without problems.
SUMMARY OF THE INVENTION
[0009] According to this invention, there is provided a tablet presser comprising a flat plate portion for pressing tablets and a plurality of diametrically outwardly extending, elastically deformable legs integrally formed at regular spacings, the legs being bent into contact the inner surface of a tablet bottle to keep the position of the flat plate portion when the tablet presser is pushed into a tablet bottle.
[0010] The legs are preferably provided with circumferential protrusions.
[0011] Also preferably, the legs have their tips bent in the same direction as the tightening direction of a screw cap of the tablet bottle.
[0012] Also preferably, a thin-walled hinge portion is provided at the root of each of the legs. A rearwardly rising projection may be provided at the tip of each of said legs. A projection protruding in the thickness direction may be provided on the flat plate portion.
[0013] The tablet presser of this invention can be easily and inexpensively formed by blanking or cutting out a soft resin sheet. Since it is simple in shape, injection molding can be carried out by use of an inexpensive mold.
[0014] Also, since they are flat as a whole and not bulky and can be handles in stacks, storage, transportation are easy, and automatic insertion using a machine can be carried out without any problems.
[0015] When pushed into a bottle, the legs are squeezed by the mouth of the bottle and bent resiliently, so that unlike the conventional article in which the disk itself is bent and forcibly pushed into a bottle, the tablet presser can be easily put in a bottle. Also, since the legs can be pinched easily, the tablet presser can be easily taken out of the bottle.
[0016] In the arrangement in which circumferential protrusions are provided on the legs, the protrusions engage the shoulder portion on the inner surface of the bottle, so that the position retaining ability improves, thereby stabilizing the pressing of tablets.
[0017] Also, in the arrangement in which the tips of the legs are bent in the same direction as the tightening direction of the cap of the bottle, the legs will not get caught on the cap. Thus it is possible to tighten the cap without trouble.
[0018] With the tablet presser in which thin hinge portions are provided at the roots of the legs, the legs are bent more smoothly, so that the tablet presser can be put into a bottle more easily. With the tablet presser in which bulged portions are provided adjacent to the roots of the legs, a difference in rigidity is present between the bulged portions and the bulge-free portions, so that the roots of the legs act as the hinge. The provision of the hinge portion decreases the bending radius of the legs and thus the gap between the bottle wall and the legs, so that even small tablets are pressed stably.
[0019] In the arrangement in which the projections are provided at the tips of the legs, the tablet presser can be easily taken out of the bottle by holding the projections with fingers.
[0020] With the arrangement in which a projection is provided on the flat plate portion, a gap is formed between stacked tablet pressers, so that separation of the tablet pressers improves.
[0021] The material forming the tablet presser according to this invention is preferably a soft resin, but is not limited thereto.
[0022] Other features and objects of the present invention will become apparent from the following description made with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] [0023]FIG. 1A is a plan view of one embodiment of the tablet presser of this invention;
[0024] [0024]FIG. 1B is a sectional view of the same;
[0025] [0025]FIG. 2 is a sectional view showing how the tablet presser of FIG. 1 is used;
[0026] [0026]FIG. 3A is a plan view of another embodiment;
[0027] [0027]FIG. 3B is a sectional view of the same;
[0028] [0028]FIG. 4 is a back view of the same with the legs bent;
[0029] [0029]FIG. 5 is a sectional view of the same with the legs protruding from the bottle;
[0030] [0030]FIG. 6A is a plan view of another embodiment;
[0031] [0031]FIG. 6B is a sectional view of the same; and
[0032] [0032]FIG. 7 is a perspective view showing a conventional tablet presser.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] The embodiments of this invention will be described with reference to FIGS. 1 - 6 .
[0034] [0034]FIG. 1 shows a tablet presser 1 of a basic form. It has a flat plate portion 2 having substantially the same size as (or slightly smaller than) the mouth of a tablet bottle and adapted to be pushed into the bottle to press the tablets in the bottle with its bottom surface. On the outer periphery of the flat plate portion 2 , elastically deformable flat legs 3 are integrally formed at a constant pitch or spacing so as to extend radially outwardly.
[0035] The legs 3 are squeezed by the mouth of the bottle and bent rearwardly when the flat plate portion 2 is pushed into the tablet bottle A as shown in FIG. 2. Under the elastic restoring force, they will contact the inner surface of the bottle A to maintain the position of the flat plate portion 2 which is pressed against the tablets B. The number and pitch of these legs 3 are preferably set so that the roots of the adjacent legs 3 will not interfere with each other.
[0036] The tablet presser 1 of FIG. 3 is provided with circumferential protrusions 3 a and 3 b on the legs 3 . As shown, the protrusions preferably comprise a combination of the protrusions 3 a and 3 b that protrude in opposite directions. But either one alone would reveal the effect. When the legs 3 are bent and pushed into a tablet bottle, the protrusions 3 a, 3 b protrude sideways and engage the inner surface of the shoulder of the bottle A provided between its trunk and mouth as shown in FIG. 4. Thus, the position retaining effect by the tablet presser 1 stabilizes. Also, tablet loopholes formed on the outer periphery of the flat plate portion 2 are reliably closed by the protrusions 3 a, 3 b, so that movement of the tablets can be suppressed more stably.
[0037] In FIG. 3A, the legs 3 have their tips 3 c bent clockwise. In the state of FIG. 5 in which the tips of the legs 3 protrude outwardly from the mouth of the bottle A, when the screw cap C is tightened clockwise, the tips of the legs will get caught by the cap, making it difficult to tighten the cap. But if the tips of the legs are bent in the tightening direction, they are pulled by the screw cap to which is applied a turning force, so that the cap can be turned without trouble. Also, as the screw cap pushes down the tips of the legs 3 during tightening, the protrusions 3 a in FIG. 4 will spread outwardly into contact with the inner surface of the bottle. This further improves the position retaining effect by the protrusions and prevents movement of the tablets.
[0038] [0038]FIGS. 6A and 6B show another embodiment in which preferable elements are further added. The tablet presser 1 of FIG. 6 is provided with a thin-walled hinge portion 4 at the root of each leg 3 , so that when pushed into a bottle, the legs 3 are bent smoothly at the hinge portions 4 . Instead of providing the hinge portion 4 , a rib-like portion may be provided adjacent to the root of each leg 3 as shown in FIG. 6B by dotted line. In this case, too, the root of each leg acts as a hinge. Though in FIG. 6B the rib-like portion is provided on the upper side, it may be provided on the opposite side. The rib-like portion increases the rigidity and at both sides of the portion where the rigidity changes, the legs 3 tend to bend as hinges. The hinge may be provided in plural according to the size of the bottle.
[0039] Also, projections 5 projecting toward one side are formed at the tips of the legs 3 . Since the tips of the legs can be pinched and pulled out of the bottle by catching the projections 5 with fingers. Thus the tablet presser 1 can be easily taken out of the bottle.
[0040] Further, a projection 6 is provided at the center of the flat plate portion 2 . Flat tablet pressers closely contact each other. Thus, especially during automated working, it is difficult to reliably peel off the topmost one. But by providing the projection 6 , gaps are formed between stacked plates, so that the plates can be separated easily. This will prevent trouble in insertion into a bottle. The projection 6 may be e.g. a small embossed portion. If the projecting amount is small, it may protrude to the front side of the flat plate portion 2 . The projection 6 should be provided on the flat plate portion 2 . If it was provided on one of the legs 3 , the legs might not align due to position displacement and it become impossible to achieve the purpose of separating sheets.
[0041] The flat tablet presser of FIGS. 1 and 3 can be mass-produced by cutting out or blanking a material sheet such as a soft resin sheet. Since a plurality of material sheets can be stacked and processed, mass-production is possible.
[0042] If the tablet presser of FIGS. 6A, 6B is formed by injection molding, it can be formed with a single manufacturing step. But it can also be manufactured by cutting out a material sheet and hot-pressing into an intended shape.
[0043] The tablet pressers according to this invention can be automatically inserted into a tablet bottle efficiently e.g. by stacking many of them, setting at a supply portion, sucking the topmost one by a vacuum pad mounted on a vertically movable and swinging arm, transferring to a portion where it is to be pushed into a bottle, and lowering the vacuum pad to push it into a tablet bottle.
[0044] As described above, the tablet presser of this invention has a flat or substantially flat shape, and will not be bulky even if many of them are stacked, so that storage and transportation are easy.
[0045] It is easy to manufacture and thus it can be provided at a low cost.
[0046] Further, supply with a stable attitude and transportation and push-in with e.g. a vacuum pad are possible, so that it can be automatically pushed into a bottle in mechanized work without problems.
[0047] With the tablet presser having circumferential protrusions provided on the legs, the protrusions engage the shoulder of the bottle, so that the position retaining force increases. This further stabilizes pressing of tablets.
[0048] With the tablet presser in which the tips of the legs are bent clockwise, tightening of the cap of the bottle can be done without trouble. Also, with the one in which the thin-walled hinge portions are provided in the legs, flexibility of the legs improves. With the one in which the protrusions are provided at the tips of the legs, it is easy to pinch the legs. Thus it is easy to take the tablet presser out of the bottle. With the one in which the projection is provided on the flat plate portion, separation of flat plates from a stack improves. Thus they can be automatically put into bottles by a machine with high reliability. | A tablet presser is proposed which is inexpensive and not bulky and which can be stacked and automatically put into a bottle without any problem. Around a flat plate portion having sustantially the same size as the mouth of a tablet bottle, an elastically deformable legs are provided to retain the position of the flat plate portion. When the legs enter the bottle while being bent, they get into contact with the inner surface of the bottle. Movement of tablets in the bottle is prevented by pressing them with the bottom surface of the flat plate portion. | 1 |
TECHNICAL FIELD
The invention relates to a switch device for switching a load on and off, especially an engine, etc., in a vehicle, with a housing, an activation element, a switch element, the switch element being activatable by the activation element, by means of which switch element at least one switch signal for a control unit can be generated, the activation element having a symbol element.
BACKGROUND
An ignition switch is described in EP 1,468,884 A1, which is used to start or turn off a vehicle engine. The ignition switch is arranged in the vicinity of a steering column and has a body arranged to be movable in a housing. A switch element is also integrated in the ignition switch, which serves to detect a displacement of the moving element. A symbol element is also situated on the moving element. This symbol element serves to display the status of the vehicle engine. In this type of ignition switch, a driver touches the moving element and moves it with his finger, so that the switch element starts or shuts off the engine. It has proven a drawback in such ignition switches that the symbol element often cannot be clearly recognized, so that a user remains unclear about the status of the vehicle.
BRIEF SUMMARY
The disclosure provides a switch mechanism for switching on and switching off of a load, in which the drawbacks mentioned are avoided, especially providing an inexpensive and compact switch device for switching a load on and off that ensures easy and user-friendly operation.
It is proposed according to the invention that a first light-guide element guides a first light of at least one first light source, so that the symbol element is illuminated uniformly.
The homogeneously illuminated symbol element permits a user to recognize the status of the switch device clearly, so that operating errors are avoided. To achieve uniform illumination of the symbol element, it is proposed according to the invention that the first light-guide element guides the first light. The task of the first light-guide element is to control the first light, which is often collimated, and, if necessary, split it, thus permitting uniform illumination of the symbol element.
In a first advantageous embodiment, it is proposed that the first light-guide element reflects the first light. The first light-guide element is a mechanical object that reflects the first light on its surface in the direction of the symbol element. This reflection can preferably occur diffusely, in order to achieve homogeneous distribution of light flux. Diffuse reflection can be achieved, in particular, by a roughened surface of the first light-guide element. If the first light impinges on the roughed surface, the first light-guide element reflects the first light with a stochastic angular distribution.
In order to achieve increased user-friendliness, the symbol element can be arranged on the activation element and inform a potential user concerning the status of the vehicle. In this case, it has proven advantageous if the first light-guide element is arranged within the housing and behind the activation element. Rear illumination of the symbol element is thereby possible by means of the first light. The first light-guide element is advantageously molded onto the activation element. This variant is to be preferred, in particular, if both the activation element and the light-guide element are made of plastic. The activation element and the first light-guide element can be produced as a unit component. This one-piece combination is preferably produced by injection molding, injection blowing, or extrusion.
Another advantageous variant of the switch device is characterized in that the first light-guide element at least partially encloses the first light source in the manner of a cap and/or screen. A system of a first light-guide element and a first light source, similar to a headlight, can be produced with the first light-guide element configured this way. Under the assumption that the symbol element is integrated into the activation element, the first light source can radiate into the housing. A first light-guide element, configured as a paraboloid of revolution, can trap the collimated first light and divert it in the direction of the activation element or the symbol element. In another advantageous embodiment, the first light-guide element has a number of reflector surfaces. Such a first light-guide element is obtained, for example, from a combination of three triangular reflector surfaces that form a triple mirror in combination. This triple mirror permits targeted reflection of the first light, which can be easily calculated in advance. An opening side of the first light-guide element then faces the activation element. The area of the light-guide element, from which the first light emerges, is referred to as the opening side. If the first light enters a section of the light-guide element and emerges from another section, by definition, the latter section is the opening side. The first light-guide element is a paraboloid, cap-like, and/or screen-like reflector, and the opening side generally faces the activation element.
In order to achieve high efficiency, in another advantageous embodiment, the reflector surface is at least partially provided with a reflector layer, the reflector layer reflecting especially the first light diffusely. A higher percentage of first light is reflected in the direction of the symbol element, because of the reflector layer. At the same time, the reflector layer reduces the part of the first light that is absorbed in the first light-guide element, which prevents heating of the first light-guide element. Depending on the application, it has proven advantageous to use a white paint or paint mixed with metal particles as reflector layer. Such types of paints are used, in particular, when the first light-guide element is produced from plastic or from a metal such as aluminum. If, on the other hand, the first light-guide element is made from stainless steel, the reflector layer can also be produced by the surface of the first light-guide element being polished to a high gloss. In addition, the reflector layer can have a luminescent and/or fluorescent material.
Depending on the first light source used, the first light can leave it almost parallel. However, such a collimated light beam is often not sufficient to ensure uniform illumination of the symbol element. Consequently, in another advantageous embodiment, it is proposed that the first light-guide element have a scattering device, which ensures widening of the collimated light beam.
However, widening of the light beam must not lead to a reduction of homogeneous distribution of the light flux on the illuminated symbol element. Consequently, it has proved advantageous to use one of the following scattering devices: a diffusing disk, a diffusing dome, or a diverging lens. The scattering devices listed ensure that a collimated light beam is uniformly widened, and homogeneous illumination of even a large-area symbol element is guaranteed. Advantageously, the diverging lens is a glass or Plexiglas element specially adapted to the wavelength of the first light, in order to achieve low absorption. The scattering device can be connected as a material unit to the light-guide element, and also have a reflector layer. The scattering device is often arranged, so that no first light can impinge directly on the symbol element from the first light source. Instead, the scattering device reflects the first light to the first light-guide element, where it is then reflected in the direction of the symbol element. This procedure reduces the probability of illumination fluctuations. Such illumination fluctuations are visible to a potential user, since certain areas of the symbol element light up more brightly than others. Overall, it has turned out that illumination fluctuations are rather unpleasant for a user and should therefore be avoided.
In an advantageous embodiment of the switch device, it can have a circuit board. The circuit board serves for mechanical attachment and electrical connection of electronic components. Such a circuit board can be produced from an insulating base plate, onto which connection lines made of a thin layer of conducting material are applied. Since the switch element of the switch device can be formed as an electronic component, it has proved advantageous to arrange this on the circuit board and supply it with power by means of the circuit board. The circuit board can therefore also be used to provide the electrical power supply to the first light source. Since the circuit board has a base plate, firm and permanent attachment of the first light-guide element can be produced simply and cheaply. The circuit board can also be equipped with all elements before being integrated into the housing. Consequently, the first light source and the first light-guide element can be precisely aligned on the circuit board without requiring complex integration beneath the housing.
For connecting the first light-guide element to the switch device, in an advantageous embodiment, the first light-guide element can have a snap device, whereby the snap device cooperates with a mating snap device of the switch device. The snap device can be a clip element that cooperates in a press-fitted and/or shape-mated manner with a receptacle element and ensures reversibly separable connection. Depending on the configuration of the switch device and the arrangement of the symbol element, the mating snap device can be arranged on at least one of the following parts: the circuit board, the housing, the activation element, or the first light source. In addition to a reversibly separable connection of the light-guide element to the switch device, the first light-guide element can also be glued into the switch device, soldered on, or sputtered on. Such bonded connections are simple and cheap to produce and are generally not influenced by environmental conditions. For connecting the first light-guide element to the switch device, common glues can be used. It is likewise possible that the first light-guide element is designed to be laser-transparent and the switch device to be laser-absorbing, so that connection of the two elements by laser welding is possible.
Another advantageous variant of the switch device is characterized in that it has a second light source. The second light source can illuminate the symbol element if the first light source fails. For this purpose, the first light-guide element can guide the first light of the first light source and a second light of the second light source, so that the symbol element is uniformly illuminated. To ensure this, the first light-guide element must have correspondingly shaped reflector areas, both for the first and the second light sources. For this purpose, the first light-guide element can have several reflector surfaces arranged stepwise, one reflector step being assigned to each light source. In another embodiment, the first light and the second light of the two light sources can have different wavelengths, in order to illuminate the symbol element in different colors. The first and second light sources are preferably connected to a computer unit that controls a switch state of the light sources. It is thus possible to activate either the first or second or both light sources through the computer unit. This has the advantage that a user can be shown a number of switch states by color changes of the symbol element.
Another advantageous embodiment of the switch device is characterized in that a second light-guide element guides the second light of the second light source. In this variant, each of the two light sources is assigned an individual light-guide element. In contrast to a first light-guide element that guides the light of two light sources, in this variant, the mechanical size of the light-guide element can be reduced. Moreover, the first and second light-guide elements are each provided with an individual reflector layer, which is adapted to the wavelength of the first and second new light. Uniform illumination of the symbol element is thereby ensured.
Depending on the arrangement of the first or second light sources, light emission of the first and/or second lights can occur essentially at right angles or parallel to an activation surface of the activation element. In the switch device according to the invention, the activation element can be manipulated by a user in order to switch on or switch off a load. The user then touches the activation surface of the activation element, which has at least the size of a finger. The activation surface often has a flat or dome-like geometry for haptic reasons. The symbol element is arranged within the activation element, and the first light source is preferably arranged behind the symbol element. The spatial configuration of the switch device generally determines the arrangement in the first and/or second light source. For example, the first and/or second light source can be arranged on the circuit board, which leads away from the activation element like a blade. In this case, the light emission of the first and/or second light sources can occur parallel to the activation surface of the movement element, i.e., at right angles to the surface of the circuit board. The first light-guide element must then deflect the first and/or second light by 90°, so that the symbol element is illuminated. It is likewise conceivable that the first light-guide element is arranged so that light emission occurs away from the activation surface of the activation element. In this case, paraboloid light-guide elements have proven advantageous, which reflect the first and/or second light in the direction of the symbol element.
In another advantageous variant, the symbol element has at least a first area and a second area. The two areas can serve to display different information to a user. The first light of the first light source can illuminate the first area and a second light of the second light source can illuminate the second area uniformly. The two areas and therefore different information can be homogeneously illuminated, in order to clearly display the user a state of the switch device.
In another advantageous embodiment, the first and/or second light source is at least one of the following: an LED, an OLED, or a fluorescent lamp. Depending on the application, one or more of the illumination elements mentioned can be combined in one light source. A light-emitting diode (LED) is a semiconductor component that emits incoherent light with a narrow spectrum. The wavelength of the emitted light depends on the semiconductor components and possible doping. An organic light-emitting diode (OLED), also usable, is a special type of LED, in which the light-emitting layer is formed from organic components.
In another advantageous variant, the first light-guide element has at least one mechanical guide element. The guide element serves to position the first light-guide element with respect to the first light source. For this purpose, the mechanical guide element can be arranged like a rail and cooperate with a side flank of the first light source, in order to ensure distinct positioning of the first light-guide element. The guide element is advantageously configured in such a way that the first light-guide element can only be mounted in alignment with the first light source.
Depending on the application, it has proved advantageous if the symbol element is arranged on, against, and/or in the activation element. The symbol element, for example, can be a row of letters that inform the user about the status of a vehicle. For this purpose, the symbol element can be milled into the activation element. It is also conceivable that the symbol element is formed from a number of light-guiding elements that are inserted into the activation element. The symbol element is advantageously formed like a film and covers at least parts of the back of the activation element, facing away from the user. Light that does not directly impinge on the individual elements of the symbol element arranged in the activation element can thus be guided toward it. Moreover, the activation element and the symbol element can be made in one piece.
In an advantageous variant, the first and/or second light source is connected to at least one computer unit through a bus system, whereby the bus system serves for mono-and/or bidirectional exchange of at least one control state of the first and/or second light source. In order to report the control state, it has proved advantageous, if the bus system has a serial or parallel architecture. Parallel architecture then denotes a digital transmission in which several bits are transmitted simultaneously (i.e., in parallel). In contrast to this, during serial data transmission, information is transmitted bit by bit in succession through the data-transmission medium. The bus system advantageously has one of the following parallel architectures: ATA (Advanced Technology Attachment), GPIB (General Purpose Interface Bus), or HIPPI (High Performance Parallel Interface). If a serial system architecture is to be used, it has proved advantageous to use one of the following architectures: ACCESS.bus, ASI-Bus, ByteFlight, Controller Area Network (CAN), European Installation Bus (EIB), ISYGLT (Innovative SYstem for Building Guide Technology), KNX, Local Control Network (LCN), FlexRay, Universal Serial Bus (USB), FireWire, eSATA (External Serial ATA), Profibus, MOST-Bus, Time-Triggered Protocol (TTP), LIN-Bus, ControlNet, INTERBUS, ML-Bus, SafetyBUS p, or Spacewire.
The switch device according to the invention, based on the space-saving embodiment, can also be arranged in or on the steering wheel itself, especially in the area of an emblem or in the area of impact or gripping surfaces. Only one or a few electrical conductors go from this switch device, so that simple cabling in the steering wheel is possible. It is even conceivable to arrange the switch device on a gearshift, on a center console, on a multifunction operating unit on the dashboard, on an internal door panel, on the sunroof, on an internal rearview mirror, or to the left and right of the steering wheel in the vehicle. Operating comfort during starting of an engine, etc., can therefore be significantly increased, since the ergonomic interests of the driver can be considered.
The present invention can also be used for a safety system for keyless activation or deactivation of a system or device, especially a steering-wheel lock (which is considered an important functional component in a vehicle) or an engine in a vehicle. This safety system is equipped with a switch device and a mobile ID transmitter, whereby data can be transmitted between the switch device and the ID transmitter. In addition, a control unit is provided in the safety system that controls at least data transmission between the switch device and the mobile ID transmitter. In this safety system, the driver or operator of the vehicle need not be actively identified, in order to cause free switching or activation of the system. Only by activation of the switch device, especially the activation element, is the identification process automatically started, in which case, data transmission is used to transmit the coded waking or activation signal from the switch device to the ID transmitter. After the mobile ID transmitter has received and checked this waking signal, it sends an identification code back to the safety system. This can also occur, on the one hand, by data transmission or by means of an additional receiver unit that receives by radio the identification data from the mobile ID transmitter and conveys it to the control unit. The control unit then compares the identification data with stipulated identification data and performs a corresponding check of the individual loads or devices with a positive identification, depending on which switch position or which switch signal of the switch device is present. For example, the electrical steering-wheel lock can be unlocked and the engine-management system released, in order to start the engine in a vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional steps and advantages of the invention can be seen from the claims, the following description, and the drawings. The invention is shown in the drawings in several embodiment examples. In the drawings:
FIG. 1 shows a front view of a switch device,
FIG. 2 shows a schematic section drawing of a switch device,
FIG. 3 shows a circuit board of a switch device, and
FIG. 4 shows a section drawing of a first light-guide element.
DETAILED DESCRIPTION
A front view of a switch device 10 for switching on or switching off a load, especially an engine in a vehicle, is shown in FIG. 1 . A housing 20 of the switch device 10 encloses an activation element 30 like a collar. By means of the activation element 30 , a switch element 40 (not shown) can be activated. Activation can occur by the activation element 30 being pushed in the direction of the plane of the drawing into the housing 20 . In the embodiment example shown, the switch device 10 is a start/stop switch for a vehicle. A symbol element 50 , which forms the words “Start” and “Stop” is arranged on the activation element 30 .
In known switch devices, it has proven to be a drawback that the symbol elements often cannot be clearly recognized by a user. Because of this, there is a possibility that the user will obtain an incorrect interpretation of the status of the vehicle. To overcome this drawback, it is proposed according to the invention that a first light-guide element guides a first light from at least a first light source, so that the symbol element 50 is uniformly illuminated.
The design of a switch device 10 configured in this way is shown by the section drawing in FIG. 2 . The housing 20 in which the activation element 30 is arranged can be seen. In the rear area of the housing 20 , a switch element 40 is arranged between a cross-connector and a frame 32 of the activation element 30 . By pushing the activation element 30 in the direction of movement arrow 31 , a switch signal for a control unit (not shown) can be generated. The frame 32 is connected to an activation surface 33 of the activation element 30 in the housing interior. A circuit board 25 is arranged within frame 32 . This circuit board 25 serves as a base for the electronics inherent in the switch device 10 . The first light source 70 , as well as two additional second light sources 80 , 80 ′, are also arranged on the circuit board 25 . The light emitted by light sources, 70 , 80 , 80 ′ flows into the plane of the drawing. In order to illuminate symbol element 50 uniformly, a switch device 10 according to the invention has a first light-guide element 60 and a second light-guide element 90 .
FIG. 3 will be used to explain the method of operation of the switch device 10 according to the invention, The circuit board 25 , the first light source 70 , and the first light-guide element 60 are shown in this drawing. The first light source 70 is a cuboid LED, arranged on a circuit board 25 . This first light source 70 is covered by the hood-like first light-guide element 60 . This first light-guide element 60 is connected to the circuit board 25 by means of at least one snap device. The snap device (not shown) can be a clip, for example, which cooperates in a press-fitted and/or shape-mated manner with a correspondingly shaped mating snap device of the circuit board 25 . The first light-guide element 60 has a number of reflector surfaces 61 , 61 ′, on which the first light 71 emitted from the first light source 70 is diffusely reflected. For this purpose, the reflector surfaces 61 , 61 ′ can be coated at least in areas with a reflector layer. The reflector layer can be a white paint having a high degree of reflection, and a large percentage of the first light 71 emitted from the first light source 70 is therefore passed through an opening 62 of the first light-guide element 60 . The symbol element 50 is arranged according to the invention in front of the opening 62 . Because of the shaping of the first light-guide element 60 and the coating of the reflector surfaces 61 , 61 ′ with the reflector layer, a homogeneous light flux is formed, which passes uniformly through the opening 62 and illuminates the symbol element 50 . This permits a user of the switch device 10 according to the invention always to be clearly informed concerning the status of the switch device 10 .
To display a variety of information, the symbol element 50 can have at least a first area 51 and a second area 52 . For uniform illumination of the second area 52 , a second light source 80 is mounted on circuit board 25 in FIG. 3 . This second light source 80 is enclosed by a second light-guide element 90 , designed like a screen. This second light-guide element 90 ensures that a second light 81 emitted by the second light source 80 homogeneously and uniformly illuminates the second area 52 of the symbol element 50 . In the embodiment example shown, the second light 81 emerges from a light outlet 82 of the second light source 80 and is reflected onto the reflector surfaces 91 of the second light-guide element 90 . In order for no brightness distribution to occur during illumination of the symbol elements 50 , the second light-guide element 90 has a scattering device 65 . If the second light 81 impinges directly on the scattering element 65 from the second light source 80 , it reflects the second light 81 on the reflector surfaces 91 of the second light-guide element 90 . Because of this, direct illumination of the symbol element 50 by the second light source 80 is prevented. Instead, it is ensured that the second light 81 of the second light source 80 is always reflected first by the second light-guide element 90 , in order to achieve uniform illumination.
The first light-guide element 60 also has a scattering device 65 ′. In contrast to this scattering device 65 of the second light guide element 90 , the scattering device 65 ′ is an indentation within the cap-like reflector surface 61 . The first light 71 of the first light 70 emerging from the light outlet surface 72 is diffusely reflected on the scattering device 65 ′, in order to also achieve uniform illumination of the symbol element 50 .
Another possible embodiment of the first light-guide element 60 according to the invention is shown in FIG. 4 . The starting point for this embodiment of the light-guide element 60 is that the symbol element 50 has two areas 51 , 52 . These two areas 51 , 52 can display different information for a user. In order to illuminate the first 51 and second area 52 uniformly, the first light source 70 and the second light source 80 are arranged one behind the other on the circuit board 25 . The first light source 71 of the first light source 70 is deflected on the reflector surface 61 of the first light-guide element 60 in the direction of the second area 52 . By corresponding coating of the reflector surface 61 , a diffuse light flux of the first light 71 is produced, which guarantees that the second area 52 is fully illuminated uniformly. The second light source 80 is arranged spatially in front of the first light source 70 . The second light 81 emitted from this second light source 80 is reflected on the reflector surface 61 ′, in order to uniformly illuminate the first area 51 of the symbol element 50 . According to the invention, a scattering device 65 is arranged between the reflector surface 61 and the reflector surface 61 ′. This scattering device 65 in the variant shown ensures that no mixing of the first light 71 and the second light 72 occurs. This prevents undesired illumination of one of the two areas 51 , 52 by a light source 70 , 80 not assigned to it. This embodiment of the light-guide element 60 has proved particularly advantageous if the first light 70 and the second light 81 have different wavelengths. The color differentiation configured in this way between the first area 51 and the second area 52 facilitates informing a potential user about the status of the switch device 10 . | The invention relates to a switching apparatus ( 10 ) for switching a load on and off, in particular a motor or the like in a vehicle, having a housing ( 20 ), an operating element ( 30 ), a switching element ( 40 ), wherein the switching element ( 40 ) can be activated by the operating element ( 30 ), and at least one switching signal for a control unit can be produced by means of the switching element ( 40 ), and the operating element ( 30 ) has a symbol element ( 50 ). The invention provides for a first optical waveguide element ( 60 ) to carry a first light ( 71 ) from at least one first light source ( 70 ) such that the symbol element ( 50 ) is uniformly illuminated. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a §371 national stage entry of International Application No. PCT/DE2008/001738, filed Oct. 24, 2008, which claims priority to German Patent Application No. 10 2007 052 027.3, filed Oct. 31, 2007, both of which are hereby incorporated by reference.
BACKGROUND
The processing of crystalline structures, in particular glass plates, in ultra-clean rooms was initially necessary in the technique for producing semiconductors. Over time, photovoltaics and the production of TFT screens, inter alia, have proved to be important fields of application for this production technique.
Tailored solar modules make accurate integration into building grids and profiles possible. Semitransparent solar cells, but also opaque solar cells with transparent areas, make photovoltaic glazings appear to be flooded with light. Here, the solar cells often take on the desired effect of protection against the sun and glare.
The production of such photovoltaic systems requires operating conditions such as those which are conventional primarily in the production of integrated electronic circuits. However, in the production of photovoltaic systems, these so-called clean room conditions additionally make it necessary to handle shock-sensitive glass plates with a large surface area.
The production and further processing of shock-sensitive plates is also required in the production of large flat screens, and in a large quantity. Modern flat screens are increasingly replacing the old tube monitors, and are also becoming less and less expensive.
These are based on TFT/LCD technology. In this context, LCD (Liquid Crystal Display) represents the use of liquid crystals in the individual pixels of the screen, and TFT stands for Thin Film Transistor. The TFTs are very small transistor elements which control the orientation, and therefore the light transmission, of the liquid crystals.
A flat-screen display consists of numerous pixels. In turn, each pixel consists of 3 LCD cells (subpixels), corresponding to the colors of red, green and blue. A 15-inch screen (measured diagonally) contains about 800,000 pixels or roughly 2.4 million LCD cells.
For understanding of the mode of operation:
A liquid crystal cell (LCD cell) works in a similar manner to polaroid sunglasses. If two polaroid glasses are held one above the other and then twisted with respect to each other, it is initially possible to see less and less and then nothing at all. This effect arises because polaroid glass is transparent only to light waves which vibrate in a specific plane. If two such glasses are held one above the other and twisted through 90° with respect to each other, some of the light can still pass through the first glass, but no longer through the second glass, since this is then transverse to the incoming light waves and filters them out.
An LCD cell works on the same principle. It consists of two polaroid glasses which are twisted through 90° with respect to each other and through which no light can therefore pass, in accordance with that explained above. A layer of liquid crystals, which has the natural property of turning the vibration plane of light, is located between these two polaroid glasses. This layer of liquid crystals is just thick enough that the light passing through the first polaroid glass is turned back through 90°, and can therefore also pass through the second polaroid glass, i.e. is visible to the viewer.
If the liquid crystal molecules are then turned away from their natural position by the application of an electrical voltage, less light passes through the cell and the corresponding pixel becomes dark. The corresponding voltage is produced by a TFT element which is part of every LCD cell. The light for the LCD display is produced in the rear part of the screen housing by small fluorescent tubes, as are used on a larger scale for illuminating rooms.
Since each pixel has three color filters for the colors of red, green and blue, the control of the transparency of these filters means that each pixel can assume a desired color mixture or a desired color.
For standard office applications, flat screens have outstanding sharpness and a sufficient color quality. In ergonomic terms, TFTs also have much to offer: smaller space requirement, a power consumption which is only a third of that of a tube monitor and significantly lower emission of radiation.
As is conventional in microelectronics, the production of TFT screens requires so-called ultra-clean rooms. This is necessary because, in view of the small size of the line-carrying structures, even small particles can cause line interruptions during the production process. In the production of a TFT screen, such a line interruption would result in the failure of a pixel.
A clean room, or an ultra-clean room, is a room in which the concentration of airborne particles is controlled. It is constructed and used in such a manner that the number of particles introduced into the room or produced and deposited in the room is as small as possible, and other parameters, such as temperature, humidity or air pressure, are controlled as required.
On the one hand, TFT screens are currently becoming less and less expensive, and on the other hand the demand for screens with enormous proportions is increasingly standing out, all the more so because screens of this type firstly can be used very easily at major events and secondly are available in affordable price ranges due to modern production technology.
However, the production of large screens requires the use of special machines even in ultra-clean rooms to handle the large-surface-area, thin glass plates required in this case.
For this purpose, it is possible to use primarily multi-axle industrial robots.
The use of a wide variety of embodiments of multi-axle industrial robots in technology for producing a wide variety of products can be gathered from the prior art. Industrial robots of this type are used in large halls mostly for transporting unmanageable and heavy loads, but can also be used beneficially in the production of smaller machine parts. What matters in all cases is the reproducible precision of the movement sequences of the individual grasping operations, transport movements and setting-down operations.
Here, the conditions in which these movement sequences take place are unimportant in many cases. For example, it is mostly immaterial which noise emission such a movement sequence causes, or whether such an operation is associated with the movement of dust or a more or less large escape of lubricant. Unavoidable abrasion of moving machine parts which cause friction is also mostly unremarkable.
By contrast, natural ramifications of this type must be taken into consideration when working in an environment at risk from contamination, for example in the food-processing industry, in the pharmaceutical industry or even in the production of semiconductors in ultra-clean rooms.
Thus, EP 1 541 296 A1 discloses a manipulator, such as an industrial robot, for use in an environment at risk from contamination, having a number of scavenging chambers, which can be charged with a scavenging medium, in the region of drive units of the manipulator. The object to be achieved in the case of such a device is to further develop the device to such an extent that the manipulator can safely be used in an environment at risk from contamination in a structurally simple manner and therefore, in particular, at low cost.
This object is achieved by a dedicated scavenging chamber being associated with each of a plurality of groups of drive units (claim 1 ).
Although the environment in which such an industrial robot is to be used is more sensitive to contamination and therefore also places higher demands on the design configuration compared to a normal environment, special demands of this type cannot be compared with the conditions demanded in ultra-clean rooms.
DE 20 2007 003 907 U1 discloses an apparatus for automatically sorting glass plates. This document describes, inter alia, an orienting apparatus ( 1 ) which orients the glass plates with respect to a left-hand and/or a right-hand abutment strip ( 7 ) via controllable rollers ( 8 ), wherein the orienting apparatus ( 1 ) comprises two frame roller carriers ( 10 ) which can each be rotated separately about a pivot bearing ( 5 ). Apart from the fact that this orienting apparatus ( 1 ) is not intended for operation in ultra-clean room conditions, in this case the orientation of thick and relatively stable glass plates takes place via impetuous abutments on two abutment strips ( 7 ). This is a completely unsuitable orientation process for the orientation of thin glass plates at risk from breaking. This document provides no indication of the particularly smooth, sliding orientation of thin, shock-sensitive glass plates according to the invention.
In the apparatus for transferring and stacking plates described in DE 19 18 791 A, the transfer speed and the stacking speed of plates should be increased considerably compared to a stacking operation according to the prior art, which is partially assisted manually. This is achieved substantially in that the lifting or inverting of each plate is performed in two steps. In order to make it possible to handle the respective plate in the process described here, said plate is connected fixedly by means of a suction device ( 4 ), fed to different rotatable carrying devices and moved into different horizontal and inclined positions until it is finally transferred to a stacking portion ( 11 ). This document provides no indication of the smooth and soft orientation of thin, shock-sensitive glass plates in ultra-clean room conditions.
DE 10 2005 039 453 A1 further discloses a modular processing system for flat substrates. In order to be protected from dirt, flat substrates of this type, for example TFT screens, are reliant upon enclosures for handling in special atmospheric conditions. According to the invention proposed in this document, an enclosure of the processing system is dispensed with; for this reason, however, the modular processing system is provided with a transfer system which makes both quick access to the individual modules and quick transfer between the individual modules possible, and which makes it possible for the substrates to be transferred between the modules even under ultra-clean room conditions. This is achieved in that the transfer unit has a transfer chamber which accommodates the substrate rest and is in the form of an enclosure, such that the size of the enclosure can be reduced to the size of the substrate, and thus to the imperative size. Although these are measures for optimizing a processing system in a certain way in ultra-clean room conditions, this document does not deal with the topic of orienting thin, shock-sensitive glass plates.
Apart from what has been mentioned above, large, thin glass plates such as those used for producing large TFT screens are extremely sensitive to very small shocks owing to their structure and concurrent relatively large mass. Therefore, an industrial robot is also unsuitable for handling large, thin glass plates in ultra-clean rooms because it lacks sensitivity and in some cases may lack positional accuracy.
In ultra-clean room conditions, the transfer of large, shock-sensitive glass plates from the horizontal orientation to a vertical orientation requires particular care and attention.
A further aspect to bear in mind when maintaining ultra-clean room conditions, particularly when producing expensive products, is the risk of contamination by people. Here, unintended sneezing can destroy a whole production unit. Likewise, such a system requires increased reliability. Since the costs for purchasing and operating an appropriately configured industrial robot are high, a favorable price of such a system is also important.
Particularly when handling large-surface-area glass plates using an industrial robot, it may be observed that large surfaces such as these tend to vibrate as a result of the movement. This can firstly be caused by the suction elements adhering only at a few points and secondly by the accelerated movement sequences of such robots. Vibration phenomena such as these bring the additional risk of glass breakage.
SUMMARY OF THE INVENTION
Therefore, the apparatus according to the invention and, respectively, the process according to the invention are based on the object of ensuring a production process, or a delivery to a specific production process, which takes place without intervention by people, but controlled and monitored by people outside the production, in the orientation and positioning of large, thin glass plates in ultra-clean room conditions. The corresponding apparatus has to be reliable and inexpensive to produce. The movement sequences of the glass plates have to rule out undesirable vibrations.
This object is achieved by an apparatus as claimed in claim 1 and by a process as claimed in claim 9 .
BRIEF DESCRIPTION OF THE DRAWINGS
The apparatus according to the invention is described in more detail below.
In detail:
FIG. 1 : is a spatial illustration of a roller conveyor,
FIG. 2 : is an illustration of the roller drive,
FIG. 3 : is a plan view of the roller conveyor and the orienting unit,
FIG. 4 : is a spatial illustration of the roller conveyor and the transfer unit,
FIG. 5 : is a spatial illustration of the roller conveyor, the orienting unit and the transfer unit, and
FIG. 6 : is a spatial illustration of the transfer unit and the setting-down apparatus.
DETAILED DESCRIPTION
For ultra-clean rooms, as are also used in microelectronics, there are a plurality of hierarchical areas with a corresponding clean room class. Thus, the ultra-clean room (class 10 and better), in which substrates are being processed, is surrounded by a separate area with the systems required for coating and structuring. Pumps required for vacuum technology are usually located on an underlying story.
Access is usually gained to the ultra-clean room through a sequence of different clean room areas with a decreasing clean room class. A change of clothes is generally required between these areas. In order to minimize soiling by items which come into contact with the floor (e.g. soles of a shoe), special sticky foot mats are located at each of the access points. Access to the ultra-clean room itself is gained additionally through air locks for people and materials in which, in turn, strong air flows and filter systems whirl up and extract particles which are present, such that no additional contamination is brought in from outside.
Materials which are used in clean rooms have to have abrasion-resistant surfaces. Systems and devices which have been erected may only cause minimum disruption to the laminar air flow. A clean room is generally subjected to overpressure (overpressure ventilation).
The glass plates ( 9 ) used in the ultra-clean room are cleaned in one of the preceding rooms and packed in a plurality of protective covers.
These protective covers are then removed again, depending on the respective processing operation of the glass plates ( 9 ) and depending on the clean room conditions or ultra-clean room conditions required.
The glass plates ( 9 ) access the room in which the orientation and positioning according to the invention take place through an air lock, through which a roller conveyor passes.
A roller conveyor of this type comprises a sequence of parallel rollers ( 2 ), as shown in FIG. 1 . Here, each roller ( 2 ) is operated via a dedicated bevel gear and a drive ( 3 ) common to all of the rollers, as can be seen from FIG. 1 . The roller conveyor can be mounted on a base plate ( 1 ).
FIG. 2 shows a detailed illustration of such a drive. It can be seen here that an elongate drive motor with a downstream angular gear mechanism uses a large bevel gear to drive a smaller bevel gear on a central shaft. This central shaft is mounted at a plurality of locations and, in the region of each roller ( 2 ), supports a smaller bevel gear, which drives a further bevel gear seated directly on the respective roller ( 2 ). This construction is inexpensive and makes reliable operation possible for many years. The use of bevel gear drives ensures that a high level of operational reliability is achieved together with inexpensive production.
The bearings of these rollers ( 2 ) are designed in accordance with the clean room conditions required.
However, a roller conveyor of this type may also comprise a sequence of rollers each with a dedicated electromotive drive and a dedicated control system, or may be provided with bevel gears which are each driven in groups. Roller conveyors are used whenever it is necessary to transport one or more glass plates ( 9 ) to the next intended location.
If the respective glass plate ( 9 ) then reaches the region of the orienting unit, as shown in FIG. 3 , its position is detected by sensors and the glass plate ( 9 ) is brought to a stop in a preliminary position. FIG. 3 shows such an operation from above; the glass plate is omitted for reasons of clarity.
A wide variety of types and arrangements of sensors of a wide variety of constructions which are familiar to a person skilled in the art can be used as sensors, depending on the respective requirements.
For the actual orientation of a glass plate ( 9 ), a lifting frame ( 8 ) bearing an orienting frame ( 5 ) is raised underneath the rollers, the orienting frame in turn bearing cross braces ( 4 ) with support elements which pass through the free space between the rollers and protrude beyond the support level of the rollers.
The lifting frame ( 8 ) is raised using a dedicated drive which brings about the deflection of lifting elements via a lever linkage and the shortening of a threaded rod. However, it is also possible to employ other options which are known to a person skilled in the art, have a lifting action and are compatible with the conditions in the ultra-clean room.
The orienting frame ( 5 ) bears support elements which are fastened on rotatably mounted cross braces ( 4 ), have an anti-marking surface, make contact with the glass plate ( 9 ) on the underside and thereby bear the latter.
The orienting frame ( 5 ) is firstly displaceably mounted on displacement supports via displacement elements which can be driven individually by drives ( 6 ), as a result of which the two longitudinally extending crossbeams of the orienting frame ( 5 ), which are connected in an articulated manner to the rotatably mounted cross braces ( 4 ), can be arranged in different positions.
This ensures that the orienting frame ( 5 ) can not only be displaced in parallel as a whole and thus finely adjusted, but can also be shifted into an inclined position like a parallelogram, and the orienting frame ( 5 ) moves the glass plate ( 9 ) resting on the support elements into the desired position in a shock-free manner.
The precise positioning of the glass plate ( 9 ) can be monitored using line lasers or markings, the position of which is monitored using lasers and/or sensors.
A glass plate ( 9 ) can therefore be positioned with the greatest possible precision and fed for further processing in ultra-clean room conditions.
This is achieved in that, after the operation for the precise orientation of the glass plate ( 9 ), monitored by sensors, the lifting frame ( 8 ) is lowered to such an extent that the glass plate ( 9 ) rests on the rollers again.
The spaces shown in FIG. 3 between the rollers ( 2 ), on the one hand, and the cross braces ( 4 ), which are positioned on the orienting frame and the push-away elements of which pass through between the rollers ( 2 ) and are displaced between them, can be set in each case on the basis of the displacement movements to be expected.
In practice, however, small orienting movements of a glass plate ( 9 ) are to be expected, such that the corresponding spaces between the rollers ( 2 ) suffice for the alignment of a glass plate ( 9 ) to be typically oriented.
FIG. 4 is a perspective illustration of a glass plate ( 9 ) on a transfer apparatus according to the invention. It can be seen in FIG. 4 how the rollers ( 2 ), along which the glass plates ( 2 ) are guided horizontally on the transfer apparatus, have conveyed a glass plate ( 2 ) into the region of the transverse strut ( 13 ) of the transfer fork and the suction head support struts ( 14 ) connected thereto at right angles. The suction head support struts ( 14 ) run substantially parallel to the rollers ( 2 ). The precise positioning of the glass plate ( 9 ) can be monitored using line lasers or markings (not shown separately), the position of which is monitored using lasers and/or sensors.
A glass plate ( 9 ) can therefore be transferred with the greatest possible precision and fed for further processing in ultra-clean room conditions.
It can also be gathered from FIG. 4 that the transfer apparatus is anchored to the floor with a fastening plate ( 1 ). The transverse strut ( 13 ) of the transfer fork is mounted on the fastening plate ( 1 ) via a fastening element and also an upper deflection gear mechanism ( 11 ) and a lower deflection gear mechanism ( 10 ) connected thereto via a crossbeam at a particular spacing. Here, the upper deflection gear mechanism ( 11 ) is driven by the upper servo drive ( 17 ), and the lower deflection gear mechanism ( 10 ) is driven by the lower servo drive ( 16 ).
By way of example, four suction head support struts ( 14 ) each with five suction heads ( 15 ) are shown on the transverse strut ( 13 ) of the transfer fork.
Before the transfer operation, the suction heads ( 15 ) are attached fixedly to the relevant glass plate ( 9 ) by suction, and connect it to the transfer apparatus. The flexible service duct ( 12 ) is encapsulated in an emission-free manner and additionally has a dedicated suction extraction system.
FIG. 5 is a drawing showing a combination of an orienting apparatus according to the invention and a transfer apparatus according to the invention.
It can be seen in the perspective view in FIG. 6 how the glass plate ( 9 ), held by the suction heads ( 15 ), has been pivoted into an upright position in the region of the setting-down apparatus ( 18 ).
The actual pivoting operation from the horizontal position into the required vertical position is substantially carried out here using the lower deflection gear mechanism ( 10 ). A glass plate ( 9 ) can then be finely adjusted further both in the horizontal direction and in the vertical direction using the upper deflection gear mechanism ( 11 ).
A glass plate ( 11 ) then remains in the setting-down apparatus ( 18 ) until the coating operation according to the actual intended use.
For adaptation to different conditions in terms of the dimensions of the glass plates to be transferred and in terms of setting-down apparatuses of different dimensions, it can be provided that the crossbeam which connects the lower deflection gear mechanism ( 10 ) and the upper deflection gear mechanism ( 11 ) is configured in such a way that the distance between these two deflection gear mechanisms ( 10 , 11 ) can be changed by motor. The current positions of the relevant system parts can be detected by control technology by sensors in order to be monitored on a screen. The comparative detection of positions of the system parts and positional data of glass plates ( 9 ) makes it possible to perform precise desired/actual comparisons and to achieve precise positioning results.
In order to provide a clear illustration, the corresponding system parts are not shown.
A suction head ( 15 ) substantially comprises a spacer bushing which, at its lower end, bears a screw connection which is adapted to the ultra-clean room conditions and by which said spacer bushing is connected to the suction head support strut ( 14 ). The interior of a suction head ( 15 ) is provided with a flow sensor which detects the air flow flowing through a suction element and forwards the measurement values determined by it in order to control the transfer apparatus.
A suction element of this type substantially consists of a special high-performance material, known by the abbreviation PEEK.
This plastic is preferably also used for other parts exposed to abrasion, e.g. the support of the rollers ( 2 ).
The apparatus according to the invention is less expensive to produce than a corresponding system with an industrial robot, and ensures a high degree of freedom from contamination; it also meets high demands with respect to operational reliability and fail safety.
Particularly when treating large-surface-area and thin plates, as will be used in the future for the production of large-surface-area screens and solar systems, the apparatus according to the invention largely prevents undesirable vibration during the movement sequences and greatly reduces the risk of breakage.
A process which protects the sensitive glass plates as they are transferred to the setting-down apparatus ( 18 ) is achieved in that the glass plate ( 9 ) is first moved toward the setting-down apparatus ( 18 ) via the deflection gear mechanisms ( 11 , 10 ) and then, after any vibration which may occur has subsided, fine adjustment takes place by moving the glass plate slowly into the final position required for further processing.
Likewise, the apparatus according to the invention can be used to convey the glass plates ( 9 ), after they have been coated in the vertical position, back from the setting-down apparatus ( 18 ) to a horizontal position using a transfer apparatus, and to place said plates on a roller conveyor for the further production process.
In this context, it should be noted that the metallic setting-down apparatus ( 18 ) is exposed to considerable temperature elevations during the processing of the glass plates ( 9 ), these temperature elevations distorting said apparatus and thus displacing the position of the glass plate ( 9 ). However, the laws according to which such displacement takes place are known in physical terms and can therefore be determined mathematically. Therefore, measurement of the temperature of the setting-down apparatus ( 18 ) can provide a remedy here, in so far as the resultant change in position of the glass plate ( 9 ) can be taken into account, as a known variable, in the processing operation.
The interactive control of the movement elements and sensors used in each case requires a special control program.
List of Reference Numerals
( 1 ) Base plate, fastening plate
( 2 ) Roller
( 3 ) Drive on the roller conveyor
( 4 ) Cross braces, accommodation of push-away elements
( 5 ) Orienting frame
( 6 ) Drive of the displacement elements
( 7 ) Rotary joints of the orienting frame
( 8 ) Lifting frame for orienting unit
( 9 ) Glass plate
( 10 ) Lower deflection gear mechanism
( 11 ) Upper deflection gear mechanism
( 12 ) Secured, flexible service duct
( 13 ) Transverse strut of the transfer fork
( 14 ) Suction head support strut
( 15 ) Suction head
( 16 ) Lower servo drive
( 17 ) Upper servo drive
( 18 ) Setting-down apparatus | Disclosed are a method and an apparatus for the contamination-free, precisely defined, horizontal orientation and subsequent transfer of thin, shock-sensitive crystalline plates, especially glass plates ( 11 ), into a defined vertical position. The glass plates ( 9 ) are oriented, transferred, and fed in the correct position for further processing without using an industrial robot and without being contaminated by humans. The apparatus is inexpensive and safe to operate. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 13/452,554 filed Apr. 20, 2012, and is incorporated by reference herein in its entirety.
TECHNICAL FIELD
[0002] This invention relates generally to tub grinders and more particularly to an improvement to the slug bars of tub grinders.
BACKGROUND
[0003] Grinders for grinding hay or other materials to be ground are shown in U.S. Pat. No. 3,912,175 to Anderson, U.S. Pat. No. 3,966,128 to Anderson et al., U.S. Pat. No. 4,033,515 to Barcell et al., U.S. Pat. No. 4,134,554 to Morlock, U.S. Pat. No. 4,210,289 to Arnoldy, U.S. Pat. No. 4,846,411 to Herron et al., U.S. Pat. No. 5,419,502 to Morey, U.S. Pat. No. 5,626,298 to Arnoldy, and U.S. Pat. No. 6,412,715 to Brand et al., all of which are incorporated herein by reference in their entirety.
[0004] Tub grinders are used to reduce the size of many things such as bales of hay, tree branches, material from demolished buildings, etc. The material is placed in the top of the “tub” portion, for example with a grappling hook or front end loader on a tractor, then the tub portion rotates around a floor as can be seen in the prior art shown in FIG. 1 of the drawings. An opening in the floor as shown in prior art FIGS. 1 and 2 is provided with rotating hammers passing between slug bars, the hammers hitting the material in the tub, reducing the size to smaller particles that are delivered to an unloading conveyor to put the ground up particles in a pile or on a trailer or the like for transporting the ground material to another place. Typically the material to be ground is moving in the direction of the tub as shown by the arrow in FIG. 1 , while the hammers are rotating in the direction shown in FIG. 1 .
[0005] One of the problems associated with tub grinders is that they do not operate at optimum efficiency for all types of material to be ground.
[0006] Accordingly a tub grinder that can be easily adapted to efficiently grind different types of material is needed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The above needs are at least partially met through provision of the apparatus described in the following detailed description, particularly when studied in conjunction with the drawings, wherein:
[0008] FIG. 1 is a typical prior art tub grinder;
[0009] FIG. 2 is a cross sectional view taken along line 2 - 2 of the prior art device of FIG. 1 ;
[0010] FIG. 3 is a side elevational view of a slug bar with one preferred configuration of a riser bar welded to the top thereof and immediately above that integral structure is shown the riser bar alone, before it is welded onto the slug bar;
[0011] FIG. 3A is an enlarged, partial cross sectional view taken along line 3 A- 3 A of FIG. 3 ;
[0012] FIG. 4A is a cross sectional view similar to the prior art view of FIG. 2 , but showing a preferred embodiment of the present invention set up for grinding material that is relatively easy to grind;
[0013] FIG. 4B is a cross sectional view similar to the prior art view of FIG. 2 , but showing a preferred embodiment of the present invention set up for grinding material that is more usual or medium to grind;
[0014] FIG. 4C is a cross sectional view similar to the prior art view of FIG. 2 , but showing a preferred embodiment of the present invention set up for grinding material that is difficult or hard to grind;
[0015] FIG. 5 is a perspective view of the embodiment of FIGS. 3 and 4B as would be seen if looking at a tub grinder from the view of FIG. 1 if it had the improvement of the present invention thereon;
[0016] FIG. 6 is a side elevational view of a riser bar similar to the one shown in FIG. 3 , but having a serrated and sharpened top surface on a part thereof; and
[0017] FIG. 6A is a cross sectional view taken along line 6 A- 6 A of FIG. 6 .
[0018] Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. Certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. The terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.
DETAILED DESCRIPTION
[0019] Referring now to the drawings, wherein like reference numerals indicate identical or similar parts throughout the several views, FIGS. 1 and 2 show a typical tub grinder 10 without the improvements of the present invention thereon and explained in the third paragraph above. The tub grinder 10 has a floor 11 that is fixed with respect to the frame of the tub grinder 10 . A rotating wall 12 is provided for moving the material within the walls of the tub wall 12 in the same general direction that the tub wall 12 is moving in order to move the material to a hammer mill 13 disposed in an opening in the floor of the tub grinder 10 . Rotation of the rotor 19 and hammers 14 in the direction shown in FIG. 2 between slug bars 15 forces material above the floor 11 down into the area above screen 16 and the hammers also force the material through the screen 16 so that the ground up material can eventually be delivered to the unloading conveyor 17 for dumping the ground up material on the ground or into a trailer or wagon or the like.
[0020] FIG. 3 is a side elevational view of a slug bar 115 with one preferred configuration of a riser bar 121 welded by welds 122 to the top of prior art part 120 thereof as shown in FIG. 3A , and immediately above that integral slug bar structure 115 in FIG. 3 is shown the riser bar 121 alone, before it is welded onto the prior art slug bar 120 .
[0021] FIG. 4A is a cross sectional view similar to the prior art view of FIG. 2 , but showing a preferred embodiment of the present invention set up for grinding material that is relatively easy to grind, such as very dry or light porous material such as alfalfa hay or Styrofoam. The rotor 119 is rotated in the direction shown by the arrow in FIG. 4A and the swinging hammers 114 do not hit the material to be ground as the hammers 114 first rotate upwardly between the slug bars 120 and riser bar portions 121 a until about point A on the riser bar portion 121 a. After that the hammers 114 gradually extend above the riser bar portions 121 a more until they are only extending above the slug bars 120 .
[0022] FIG. 4B is a cross sectional view similar to the view of FIG. 4A , but showing a preferred embodiment of the present invention set up for grinding material that is average or medium to grind, such as wet or dense material like high moisture hay or fescue hay or medium porous material or the like. The rotor 119 is rotated in the direction shown by the arrow in FIG. 4B and the swinging hammers 114 do not hit the material to be ground as the hammers 114 first rotate upwardly between the slug bars 120 and riser bar portions 121 until about point B on the riser bar portion 121 . After that the hammers 114 gradually extend above the riser bar portions 121 a more until they are only extending above the slug bars 120 . Since the riser bar portion 121 is longer an higher for more of the length of the riser bar 121 than for the riser bar portion 121 a in FIG. 4A , the hammers 114 only extend above the riser bar portions 121 starting at point B where the hammer is substantially vertically oriented, therefore since the hammers 114 extend above the riser bars for less time and do not extend above the riser bars as far during such relative time, a less aggressive approach is taken which requires less horsepower to rotate the rotor 119 and doesn't slow the revolutions per minute (rpm) as much as if the same medium to grind material was in the tub grinder arrangement shown in FIG. 4A . Keeping the rpm of the rotor 119 (and therefore the rpm of an engine that rotates the rotor 119 ) above a certain predetermined level is important to the efficiency of a tub grinder and also reduces the wear and tear on such equipment such as the engine powering the tub grinder. The hammers 114 force the material through a screen 116 similar to FIG. 2 .
[0023] FIG. 4C is a cross sectional view similar to the view of FIGS. 4A and 4B , but showing a preferred embodiment of the present invention set up for grinding material that is difficult or hard to grind, such as very dense material like wood, rubber, rubber tires or the like. The rotor 119 is rotated in the direction shown by the arrow in FIG. 4C and the swinging hammers 114 do not hit the material to be ground as the hammers 114 first rotate upwardly between the slug bars 120 and riser bar portions 121 c until about point C on the riser bar portion 121 c. After that the hammers 114 gradually extend above the riser bar portions 121 c more until they are only extending above the slug bars 120 . Since the riser bar portion 121 c is longer an higher for more of the length of the riser bar 121 c than for the riser bar portion 121 a in FIG. 4A or riser bar portion 121 of FIG. 4B , the hammers 114 only extend above the riser bar portions 121 starting at point C where the hammer 114 is substantially past vertically oriented, therefore since the hammers 114 extend above the riser bars 121 c for less time than when riser bars 121 or 121 a are used and do not extend above the riser bars 121 c as far during such relative time, a less aggressive approach is being taken than when the riser bars 121 or 121 a are used, which requires less horsepower to rotate the rotor 119 and doesn't slow the revolutions per minute (rpm) as much as if the same easy to grind or medium to grind material was in the tub grinder arrangement shown in FIG. 4A or FIG. 4B respectively.
[0024] FIG. 5 is a perspective view of the embodiment of FIGS. 3 and 4B as would be seen if looking at a tub grinder 10 from the view of FIG. 1 if it had the improvement of the present invention thereon. Slug bars 120 have riser bar portions 121 welded to the top thereof and the hammers 114 are shown passing between the slug bars 120 and riser bar portions 121 to gradually begin grinding material as the hammers 114 move to the right in the direction of the arrow shown in FIG. 5 .
[0025] FIG. 6 is a side elevational view of a riser bar 221 similar to the riser bar 121 shown in FIG. 3 , but having a serrated and sharpened top surface 222 on a part thereof. FIG. 6A is a cross sectional view taken along line 6 A- 6 A of FIG. 6 and shows how the serrated part 222 is also sharpened to an edge. Using this alternate embodiment will provide additional cutting action as the hammers 114 force the material against the sharpened serrated edge 222 .
[0026] Those skilled in the art will recognize that a wide variety of modifications, alterations, and combinations can be made with respect to the above described embodiments without departing from the spirit and scope of the invention, and that such modifications, alterations, and combinations are to be viewed as being within the ambit of the inventive concept as expressed by the attached claims. | A tub grinder has a rotor with hammers that pass between adjacent slug bars. The slug bars have a riser bar portion disposed on the top of the slug bars, the riser bar portions extending vertically higher on one end of each respective slug bar than on the other end of each respective slug bar so that the hammers extend farther beyond the top of the riser bar and slug bar when they pass by first end than when they pass by the second end of the riser bar. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to and claims priority from earlier filed provisional patent application Ser. No. 60/753,871, filed Dec. 23, 2005.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to an innovative handle construction, that can be used on an implement or tool, such as for a toothbrush or razor. There are many different types of tools, implements and objects, such as razors and toothbrushes, that require fairly precise handling and yet both also benefit from having a soft feel for the user while handling.
[0003] In the prior art, by way of example, there are various razors or toothbrushes that are made of rigid plastic or metal and are thus hard to the touch. There have also been many attempts to make razors and toothbrushes that are more comfortable for human contact, such as by the hands and fingers. The entire razor or toothbrush does not need to be soft; rather it is desirable for much of these handles to be rigid so they are easy to control. It is generally thought to be desirable for the areas in contact with the fingers to be soft so as to lesson the pressure on the fingers. For this reason, prior art razors, toothbrushes and other tools and implements have been made with areas of softer materials. Because very low durometer gels are generally very sticky to the touch and have other undesirable surface characteristics, most of what are considered low durometer materials that are used in prior art razor and toothbrush handles are of a 50 shore A hardness or above.
[0004] In the prior art, in order to get the finished molded razor handle softer, for example, these 50 shore A or similar durometer plastics are often molded into shapes with thin “fins”. These thin fins can behave like a softer material, because the plastic will bend more easily at thin gauge. In this way, the prior art has attempted to create toothbrush and razor handles that have areas that are as soft as possible and yet durable.
[0005] There have also been examples in the prior art of the use of thermoplastic elastomers with durometers as low as 70 shore 00 hardness in toothbrush handles. TPE's in this hardness range have been used as some can be made to have acceptable surface characteristics and durability, and have not necessitated a film surface or polymer top finish coat.
[0006] In view of the foregoing problems associated with the prior art, there is a need for handles with significantly softer materials than are found in any of the prior art, such that the touch points will conform more readily to the pressure of the fingertips. There is a need for a handle construction, for use on razor, toothbrushes, and that like, that is more comfortable than those existing in the prior art. There is a need for a handle that incorporates three dimensional molded gel of less than 65 shore 00, and a top surface layer of elastomeric film or an elastomeric polymer surface coating.
SUMMARY OF THE INVENTION
[0007] The present invention preserves the advantages of prior handles with cushioning elements therein. In addition, it provides new advantages not found in currently available cushioned handle constructions and overcomes many disadvantages of such currently available handle constructions.
[0008] The handle construction of the present invention includes a low durometer grip portion that provides comfort and an ergonomic benefit to the user. More specifically, the present invention relates to handles or any gripping surfaces or areas, such as for a toothbrush or razor, with a grip with both rigid areas and areas containing three-dimensional molded gel with a durometer of less than 65 shore 00. The grip areas with three dimensional molded low durometer gel also then have a thin top layer of elastomeric film of less than 4 thousandths of an inch in thickness (<4 mil) to provide a durable and aesthetic surface, or instead of the film they have an elastomeric polymer top-coating. The combination of the molded low durometer gel “medallions”, with an otherwise rigid grip, allows for the creation of a grip that has areas that are more rigid along with areas that exhibit a very soft feel. The thickness of the gel does not need to be uniform, but can be thicker in areas where such is advantageous or aesthetically pleasing to the user.
[0009] It is therefore an object of the present invention to provide a superior handle construction that is soft to the touch to the user in the appropriate locations.
[0010] There is a further object of the present invention to provide a handle construction that incorporates three dimensional gel material for superior comfort and control for the user.
[0011] There is also an object of the present invention to provide a handle construction that complements a rigid core to combine comfort and control in the same handle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The novel features which are characteristic of the present invention are set forth in the appended claims. However, the invention's preferred embodiments, together with further objects and attendant advantages, will be best understood by reference to the following detailed description taken in connection with the accompanying drawings in which:
[0013] FIG. 1 is perspective view of the a implement having a handle with a gel medallion in accordance with the present invention;
[0014] FIG. 2 is a cross-sectional view through the line 2 - 2 of FIG. 1 showing the preferred embodiment of the present invention;
[0015] FIG. 3 is a cross-sectional view through the line 2 - 2 of FIG. 1 showing an alternative embodiment of the present invention; and
[0016] FIG. 4 is a cross-sectional view through the line 2 - 2 of FIG. 1 showing a further alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] The present invention relates to the creation of a handle 10 for tools, implements and objects, such as handles for toothbrushes and razors, that is softer to the touch than any previous design, and yet is durable and aesthetically pleasing and is rigid enough for exacting control by the user. It should be understood that the construction of the present invention is shown and described in connection with a toothbrush and razor handle 10 by way of example for ease of discussion and illustration. Any type of tool, implement or object can take advantage of the construction of the present invention.
[0018] Turning first to FIG. 1 , the invention includes an implement 2 , such as a razor or toothbrush with a handle construction 10 containing a number of elements. First, a rigid shaped core 12 of plastic or metal provides structure and shape of the implement 2 . One or more areas or “medallions” or members, generally referred to as 14 , with a molded urethane, silicone or other polymer gel 16 of preferably less than 65 shore 00 durometer is also provided. One cushioning member 14 is shown, by way of example.
[0019] As can be seen in FIG. 2 , preferably, the cushioning member 14 is located within a recess 18 formed in the rigid core 12 of the handle implement 2 . A thin outer layer 20 , such as an elastomeric polymer coating or elastomeric film covers the top surface 16 a of the molded cushioning gel 16 .
[0020] Optionally, this outer layer 20 can contain antimicrobial agents such as silver, copper and zinc. More specifically, nano-particle metals, including silver, copper and zinc, can be used as the antimicrobial agents, such as those manufactured by the Nano-Horizons Company. The outer layer 20 , such as the film or polymer coating, can optionally contain antimicrobial agents to control the growth of bacteria. By having these antimicrobial agents in the top surface layer 20 only, they can be used very economically in small quantities and yet still be highly functional since they are on the entire surface. In one embodiment, an Omniflex 18411 film containing silver active agents can be employed as an antimicrobial. It is also possible to use a water-based polyurethane coating as layer 20 with silver antimicrobial additive. Other non-silver based antimicrobial agents can also be used in the top film or coating layer 20 .
[0021] In addition, the outer layer 20 may contain phase change materials that can make the surface feel cool to the touch. Such phase change materials can be added to the outer layer 20 , namely, a surface film or elastomeric surface coating. The addition of phase change materials such as phase change containing microspheres sold under the brand name of “Outlast” can create the sensation of coolness for the user as they absorb body heat. The Outlast material consists of small spheres filled with wax type materials that melt between 75 and 95 degrees F., which is just below body temperature. As these materials melt, they absorb heat. Because of the thin outer layer 20 in the present invention, these phase change materials can be added in small quantities and yet be present on the surface of the implement 2 to come in direct contact with the user of the implement 2 . The construction of the present invention is thus well suited to deliver the benefits of these phase change materials in an economical way.
[0022] Optionally, the cushioning member 14 , made of gel 16 , can sit on a lower base layer 22 , that may be any material, such as fabric, film, or nonwoven providing for stability. For example, FIGS. 2-4 illustrate various embodiments of the present invention employing this multilayer construction. This lower layer 22 of fabric, film, or nonwoven material can additionally be printed or colored to provide additional aesthetics.
[0023] In FIG. 2 , it is preferred that the cushioning member 14 , made of gel material 16 , resides within a recess seat 18 of the rigid core member 12 . The lower layer 22 resides therebetween. However, it is also possible that the rigid core 12 can be molded or shaped to partially or fully contain the molded cushioning member 14 , of the gel material 16 , can extend entirely outside of the rigid core 12 . In FIG. 3 , the gel member 16 includes a flange 24 while the lower layer also includes a flange 26 . These flanges 24 , 26 extend outwardly for encapsulation by the rigid core member 12 . In this example, it is preferred that the rigid core member 12 molded to encapsulate the flanges 24 , 26 of the gel material 16 and lower layer 22 . As a result, the gel member 16 and lower layer 22 are fixedly secured to the rigid core 12 . FIG. 4 further shows that all layers, namely, the gel material 16 , top surface finish layer 20 and lower layer 22 all emanate outwardly to provide respective flanges 24 , 26 and 28 for encapsulation during the molding or formation process. It is also possible that this flange can be locked in by snapping together two “clamshell” pieces rather than during the molding or formation of the rigid core. If a line were to be drawn on the diagram showing that the rigid core is two snapped-together pieces locking in the flange, this might show a more likely typical use. Also, another embodiment is possible where just the lower layer 26 is the flange, and neither the gel nor the top layer are locked in.
[0024] The rigid core 12 and the gel member 16 act together to provide both stability and comfort to the user. It should be understood that each layer can be molded and formed using different methods and of appropriate varying thicknesses and shapes to achieve the best comfort and aesthetics for a given application.
[0025] It has been found that a molded gel member 16 with a durometer of less than 65 shore 00 is preferred. More generally, a preferred range for the hardness of the gel member 16 for aesthetics and durability of the handle is between 25 shore 00 and 60 shore 00. However, a gel material 16 having a hardness greater or less than this range can also be used. One preferred embodiment of the invention uses a polyurethane gel with a durometer of 50-55 shore 00.
[0026] The gel member 16 may optionally be finished with a top layer 20 . This top layer 20 may be in many different forms. For example, the top layer 20 , as seen in FIGS. 2-4 , may be a film, such as an elastomeric film with a preferred thickness of less than 4 mil. Generally, for the top finish layer 20 , it is desirable to have a film less than 2 mil thick to provide for the best combination of softness and durability. In some cases, films of up to 4 mil in thickness may be necessary to pass certain puncture or bite specifications. It has been found that for many uses a polyurethane film with a thickness of between 0.4 mil and 1.0 mil works very well. Greater thickness provides for less softness but more durability. The top finish layer 20 is preferably an elastomeric film so that it can move with the gel. Non-elastomeric films, although they can be used, are not as desirable because they will feel hard even over a very soft gel member. In one embodiment of the invention, a style 18411 0.75 mil film manufactured by Omniflex LLC of Greenfield, Mass. has been used with good results.
[0027] As an alternative to the outer surface layer 20 being a film covering, the gel material 16 can be coated with a thin layer of elastomeric polymer coating. In accordance with the present invention, a water-based polyurethane top coating 20 is employed, but other elastomeric coatings can be used including other types of water based coatings, 100% solids coatings and solvent based coatings.
[0028] The outer finish layer 20 provides for encapsulation of the molded low durometer gel material 16 , so that there is an aesthetically pleasing point of contact for the user. Either the elastomeric surface film or the polymer top-coating can be pigmented, printed up or transparent depending on the desired aesthetics.
[0029] Because the gel material 16 in the present invention is extremely soft, it is sometimes undesirable to have the edge 16 b of the molded gel 16 flush with the more rigid plastic. This can create a sharp or hard feeling at the transition point between the gel member 16 and the recess seat 18 of the more rigid core member 12 . This is generally not a problem in the prior art, because the prior art uses higher durometer materials that are not so dramatically softer than the surrounding materials. In the present invention, because of the use of very low durometer gel materials 16 , it is often desirable to have the edges 16 b of molded gel material 16 raised above the top edge 12 a of the rigid core member 12 as seen in the cross-sectional views in FIGS. 2-4 . In this way, the user is not exposed to a hard edge at the transition point.
[0030] It has also been found that it is often desirable to have a lower layer of material 22 , such as a film, fabric or nonwoven material bonded to the underside of the gel member 16 for the purpose of adding stability and durability to the gel member 16 . In accordance with the present invention, a polyester film in a thickness of 2 mil may be employed for this purpose. It has also been found that many fabrics (both knitted and woven) can work well in adding stability to the product. Also, a nonwoven material can be used in this lower layer 22 .
[0031] In addition to stabilizing the product, it has also been found that a clear or tinted molded gel material 16 transmits the aesthetics of the lower layer 22 , in the form of a fabric, film, or nonwoven material positioned therebelow. Thus it is often desirable to have a colored or printed film or fabric beneath the gel member 16 for aesthetic purposes. It has been found that printed polyester films, or dyed or printed fabrics or nonwovens can all work well in this regard for the lower layer 22 . In accordance with the present invention, a printed knitted polyester fabric beneath the gel material 16 can be used, for example. Also, for example, a printed polyester film beneath the gel member 16 may be used. In each case, the surface aesthetics of the gel member 16 takes on the color or printing of the lower layer 22 disposed therebelow. The addition of this printed or colored lower layer can greatly contribute to the aesthetics of the finished implement 2 , namely, a toothbrush or razor, and the like.
[0032] The present invention allows for a novel integration of materials for any type of tool, implement or object, such as the handle 10 for a toothbrush or razor, providing for a softer feel not found in the prior art. The ability to further enhance the aesthetics by providing graphics that show through the gel material 16 is an advance over the prior art. Further, the addition of surface antimicrobial materials or phase change materials to a cushioning gel member 16 in a handle 10 creates additional advantages unseen in any prior art.
[0033] It would be appreciated by those skilled in the art that various changes and modifications can be made to the illustrated embodiments without departing from the spirit of the present invention. All such modifications and changes are intended to be within the scope of the present invention. | The handle construction of the present invention includes a low durometer grip portion that provides comfort and an ergonomic benefit to the user. The handle includes a rigid core with a gel member received in a recessed seat. The gel member preferably has a durometer of 65 Shore 00 or less. A thin top finish layer, of elastomeric or polymer film, is optionally provided on the top of the gel member, such as in a thickness of less than 4 thousandths of an inch in thickness (<4 mil) to provide a durable and aesthetic surface. The combination of the molded low durometer gel member, with an otherwise rigid handle, allows for the creation of an overall handle that has areas that are more rigid along with areas that exhibit a very soft feel. | 8 |
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