A method and apparatus to produce controlled ablation of material through the use of laser pulses of short pulse widths at short wavelengths.

Silicon is the most widely used material for substrates of integrated circuits and forms the basis of the modern semiconductor industry. The processing of dielectric materials, primarily silicon and doped silicon, using chemical or plasma etching techniques, is a mature technology, developed mainly for the microelectronics sector. These "conventional" processes produce exceptional results for digital CMOS circuitry. However, MEMS devices, which are also fabricated on silicon, are analog devices that require much tighter spatial control and depth control than the digital CMOS circuitry.
Conventional chemical or plasma etching techniques lack the spatial control needed for high performance MEMS devices. Although the conventional etch process starts on an area having a selected diameter, the effect of the etch process extends beyond the etch dimension beyond the desired area, leading to reduced control of the material removal process.
In the early prior art of laser ablation, lasers are used to provide a directed source of radiation whose deposited laser energy leads to the thermal heating of the substrate. However, there are many situations where heating is not desired and is, in fact, harmful. In these situations, such lasers may not be used. For example, long wavelength lasers, such as infrared lasers, which cut by heating a material substrate rather than by controlled photochemical ablation, are normally not desirable for etching since the etched region undergoes heating effects leading to uncontrolled melting.
Short pulse width infrared lasers exhibit some improvement in the control of the etch process as pulse width is reduced. For example, U.S. Pat. No. 5,656,186, Morrow et al. describes a laser with a pulse width of 100 fs to 1 ps at a 800 nm wavelength. See also, U.S. Pat. Nos. 7,560,658, 7,649,153 and 7,671,295. Now laser ablation using short pulses at long wavelength typically involves Ti:Sapphire (Ti:AlO3) lasers with pulses of 100 fs (0.1 ps) at a wavelength of 800 nm. The 100 fs pulse avoids phonon-phonon or electron-phonon coupling, which begins to occur at about 1.0 ps, but requires threshold intensities in excess of 1013 W/cm2 with a per pulse ablation depth of 300-1,000 nm. This per pulse ablation depth is greater than the thickness of many microcircuit layers, which is an uncontrolled event for microcircuit processing.
Alternatively, long pulse width, short wavelength lasers etch materials efficiently, but the etch process is still not adequately controlled. See, e.g., U.S. Pat. Nos. 4,925,523 and 7,469,831. The laser deposits energy in a layer close to the surface of the material to be etched. A molten area forms leading to vaporization of the surface. The vapor pressure of the material aids removing the material by expulsion. Strong shock waves of the expulsion can lead to splatter, casting of material, and thermal cracking of the substrate, which interferes with the clean removal of the material.
This laser ablation using long pulses at short wavelength typically involves UV KrF excimer lasers, or similar ultraviolet lasers, with pulses of 1.0 ns or longer at a wavelength of 248 nm. However, this technique produces uncontrolled ablation with spalling and cratering. The uncontrolled ablation is a result of heating and melting of the material to be ablated beyond the laser spot size due to thermal (phonon-phonon) coupling during the laser pulse.
Thus, current technologies for laser ablation of materials use either long pulses at short wavelength or short pulses at long wavelength. Both technologies have significant short comings as described above. It is, therefore, desirable to ablate materials using lasers that have a short pulse length at a short wavelength. Such lasers remove material without undue heating or damage to the areas surrounding the laser sport and have the depth control desired. The ablation mechanism is different than that of the prior art.
Thus, a method and apparatus for controlled laser ablation of material is needed that avoids the spalling from longer pulses (>1.0 ps) and the excessive ablation from longer wavelengths. It is a goal of the present invention to achieve such controlled ablation through lowering the threshold intensity required for ablation in materials such as silicon; materials with crystalline substrates similar to silicon, defined herein as silicon nitride, silicon oxide, gallium arsenide, indium phosphide or sapphire; metals; or metal oxides.

Method and apparatus for controlled laser ablation of material


A liquid crystal display device includes a first flexible substrate and a second flexible substrate, a liquid crystal layer sealed between the first substrate and the second substrate by a frame-shaped sealing member, a display area located inside the sealing member, a non-display area located outside the display area and a plurality of spacers interposed between the first substrate and the second substrate. A relief area in which a gap between the first substrate and the second substrate is larger than that in the display area is provided in at least a portion of the non-display area.

1. Field of the Invention
The present invention relates to a flexible liquid crystal display device.
2. Description of the Related Art
In recent years, so-called flat panel displays have widely been used as display devices in various fields. As one of such display devices, a liquid crystal display device has broadly been used in the field of mobile displays such as cellular phones and PDAs by taking advantage of its advantages of thinness, lightness and low power consumption. In this field, there is a growing demand for thinner and lighter displays and flexibility for realizing wearable displays is also required. Therefore, use of a flexible substrate made of plastic or the like instead of glass has been under review.
As shown in a sectional view of FIG. 23, a liquid crystal display device 100 includes a first flexible substrate 101, a second flexible substrate 102 and a liquid crystal layer 104 sealed between the substrates 101 and 102 by a rectangular frame-like sealing member 103. The thickness of the liquid crystal layer 104 is controlled by spacers 105 provided between the substrates 101 and 102. The spacers 105 may be glass or resin particles of uniform particle size or columnar photo spacers. FIG. 23 shows a plurality of photo spacers 105 formed on the first flexible substrate 101.
An area enclosed with the sealing member 103 functions as a display area which contributes to display and a peripheral area outside the display area is a frame area which does not contribute to display. When the liquid crystal display device 100 is in a flat state, the width L1 of the display area on the first flexible substrate 101 is equal to the width L2 of the display area on the second flexible substrate 102 as shown in FIG. 23.
When the liquid crystal display device 100 is bent such that the first flexible substrate 101 protrudes outward, tensile force is applied to the outside first flexible substrate 101 and compression force is applied to the inside second flexible substrate 102 as shown in a sectional view of FIG. 24 due to the difference between the radii of curvature R1 and R2 of the first and second flexible substrates 101 and 102.
As a result, when the liquid crystal display device 100 is bent, the compression force is applied in the thickness direction to part of the liquid crystal layer in the middle of the display area. At the same time, part of the second flexible substrate 102 in the display area close to the sealing member 103 is convexly deformed (protrudes in the direction toward the center of curvature) and the cell gap increases. Further, peel stress is applied to part of the second flexible substrate 102 near the sealing member 103 in the direction away from the first flexible substrate 101.
Due to the existence of the spacers 105 such as photo spacers, the cell gap in the middle of the display area is not reduced below the thickness of the spacers 105. On the other hand, in the vicinity of the sealing member 103, the cell gap and the peel stress on the sealing member 103 become larger as the radii of curvature R1 and R2 become smaller. Since the stress is continuously applied to the sealing member 103, the liquid crystal display device 100 becomes less reliable. Further, the increase of the cell gap leads to reduction of display quality in the vicinity of the sealing member 103.
As a solution to the cell gap failure, a liquid crystal pool is provided between the display area and the sealing member (see, for example, Japanese Unexamined Patent Publication No. 2000-199891). To be more specific, as shown in a perspective view of FIG. 25, a liquid crystal display device 100 according to Japanese Unexamined Patent Publication No. 2000-199891 includes liquid crystal pools P1 formed in areas W1 and W2 on the edges of a bent display panel in the bending direction of the panel (hereinafter merely referred to as the edge areas). In each of the edge areas W1 and W2, linear sealing members 108 are arranged inside the sealing member 103 in a broken line pattern extending parallel to the sealing member 103. An area partitioned by the linear sealing members 108 and the sealing member 103 outside the linear sealing members 108 is the liquid crystal pool P1. A display area 110 is formed between the broken lines made of the linear sealing members 108.
When the liquid crystal display device 100 of Japanese Unexamined Patent Publication No. 2000-199891 is bent, liquid crystal in the display area 110 flows toward the edge areas W1 and W2 and overflows into the liquid crystal pools P1 through gaps 108a between the linear sealing members 108. With this configuration, the possibility of occurrence of the cell gap failure in the vicinity of the sealing member 103 is reduced and the cell gap in the display area 110 is kept uniform for the purpose of preventing the reduction of display quality.
In general, the liquid crystal display device is a flexible display panel using a flexible plate. Therefore, the peel stress is easily applied to the sealing member due to local deformation not only when the panel is intentionally bent but also in usual work on the liquid crystal display device.
As a countermeasure to this, the thickness of the sealing member is set larger than the cell gap in the display area (See, for example, Japanese Unexamined Patent Publication No. 2001-13508 and Japanese Unexamined Patent Publication No. 58-193518). According to Japanese Unexamined Patent Publication No. 2001-13508, as shown in a sectional view of FIG. 22, the diameter of spacer particles 106 contained in the sealing member 103 is set larger than the thickness of the spacers 105 in the display area 110 between the first and second flexible substrates 101 and 102 such that the thickness of the sealing member 103 becomes larger than the cell gap in the display area 110. Likewise, the sealing member according to Japanese Unexamined Patent Publication No. 58-193518 is also thickened. This configuration is intended to improve the uniformity in display of the liquid crystal display panel using the flexible plate.
For the liquid crystal display device of Japanese Unexamined Patent Publication No. 2000-199891, it is impossible to prevent the increase of the cell gap in the vicinity of the linear sealing members due to the difference in radius of curvature between the first and second flexible substrates as explained with reference to FIG. 24. That is, the display quality may deteriorate in part of the display area near the linear sealing members due to the cell gap failure.
As to the liquid crystal display devices of Japanese Unexamined Patent Publication No. 2001-13508 and Japanese Unexamined Patent Publication No. 58-193518, part of the sealing member 103 in which the spacer 106 exists has the same thickness as the diameter of the spacer 106, while part of the sealing member 103 near the display area 110 is gradually reduced in thickness toward the display area 110 as shown in FIG. 22. This is because the sealing member 103 is spread to an inside area where the cell gap is smaller than the thickness of the spacer 106 when the plates are bonded. Therefore, part of the sealing member 103 near the interface with the liquid crystal layer 104 becomes thinner than the middle part thereof.
Specifically, the cell gap at an interface between the sealing member 103 and the display area 110 is substantially the same as that in the display area 110. Therefore, the peel stress is applied to the sealing member 103, which leads to the reduction in reliability of the liquid crystal display device.

Liquid crystal display device including a relief area


The present invention relates to cyclohexanedione derivatives or salts thereof and herbicides containing the cyclohexanedione derivatives and/or salts thereof as active ingredients, the cyclohexanedione derivatives having the general formula (I). ##STR1## The cyclohexanedione derivatives or the salts thereof can selectively control a broad range of upland soil weeds at a low dosage without causing phytotoxicity on crops cultivated in upland fields such as corn, in both upland pre-emergence and post-emergence treatments.

Herbicides are very important chemicals for labor-saving of weed control working and production improvement in horticultural crops. Herbicides have been therefore aggressively studied and developed for a long time, and a variety of chemicals are now practically used. However, it is still desired to develop novel herbicides having further superior herbicidal properties, particularly herbicides which can selectively control object weeds alone at a low dosage without causing phytotoxicity on cultivated crops.
During the planting time of corn, triazine-containing herbicides such as atrazine and acid anilide-containing herbicides such as alachlor and metolachlor have been conventionally used. However, atrazine shows low efficacy to grass weeds, and on the other hand, alachlor and metolachlor show low efficacy to broad-leaved weeds. It is therefore difficult at present to control grass weeds and broad-leaved weeds together simultaneously with a single herbicide. Further, these herbicides are undesirable in view of an environmental problem due to their high dosage requirement.
In view of the above circumstances, the present inventors have developed novel cyclohexanedione derivatives having a thiochroman ring and have filed patent applications therefor (WO94/04524 and WO94/08988). Typical examples of these compounds are as follows.
Compounds described in WO94/04524 ##STR2##
Compounds described in WO94/08988 ##STR3##
As a cyclohexanedione derivative having bicyclic properties, the following compounds have been disclosed (European Patent 94/283261). ##STR4##
Since, however, the above compounds show phytotoxicity on sorgo and beet, it cannot be said that they have sufficient activity both in post-emergence treatment and pre-emergence treatment.

Cyclohexanedione derivatives and herbicides containing them


A data transfer system is provided for use in shifting and transferring image data and the like, wherein the amount of shift, the horizontal size and the like of data to be shifted are held in a dedicated circuit which is connected between a CPU and a memory. A judgment is made: by a valid/invalid indication unit, based on a valid/invalid parameter or the amount of deviation between the boundary unit and the transferred data after shifting, of the validity or invalidity of the head end or the trailing end of the data after shifting. A transfer suspension control unit eliminates the transfer of the data if the data is invalid after shifting, thereby enabling the increase of the speed of transfer of image data by avoiding the transfer of meaningless data.

1. Field of the Invention
The present invention relates to a data transfer control method and data transfer circuit capable of completing high-speed data transfer by eliminating unnecessary data when transferring image data, for a personal computer or word processor, while shifting it.
For example, when transferring image data which is generated from outline fonts to a video RAM, it is necessary to shift and transfer the data, and it is desirable to achieve high-speed processing of such transfer.
2. Description of the Related Art
In the past, when transferring image data while shifting the data, the size of the data in units of boundary was held as data, and if N data were received for each horizontal line of image data, N+1 writing operations were automatically performed, regardless of whether or not the image data was meaningful.
As a result, there arose a state in which part of the data transferred was unnecessary data.
The prior art includes an "apparatus for reading data from a bit-map display memory," as disclosed in the Unexamined Patent Application Publication (JP-A) Sho 63-278181. However, while this "apparatus for reading data from a bit-map display memory" was capable of continuously reducing the burden on the CPU by setting the amount of shift into a shifting means, there is no mention of useless data which is generated by the shifting of the data edges.
As will be explained, later and in detail, with reference to the accompanying drawings, when image data, starting from a boundary partition, which boundary is the unit of data writing, is shifted and transferred, the right end data of a horizontal line can contain a part that is meaningless as image data.
If the read range of image data that was input (read) at, for example, four times per horizontal line is shifted, after which it is output (written) at five times per horizontal line, the last write data becomes unnecessary. That is, the image data written at the fifth write operation is absolutely no data which is valid meaningful image data. This is because there is no determination made during the read operation as to how far the meaningful image data extends and the image data is defined in coarse boundary units.
After shifting, if the starting position of the image data does not coincide with a boundary partition, depending upon the size of the image data, and also on the relative positions between the boundary unit, which is the reading unit, and the image data, it is possible to write data which was read in with N read operations for each line by either N or N-1 write operations. However, in the prior art, because N+1 write operations were normally performed, either 1 or 2 write operations were unnecessary.

Apparatus for image data to be displayed by transferring only data which is determined to be valid after shifting the data over a range of given length


A system for determining a real time solid flow rate of a solid-gas mixture is provided. The system includes multiple sensors, a data-fusion unit and an estimating unit. The sensors generate multiple measurement signals for obtaining at least two measured values of the real time solid flow rate. The data-fusion unit receives the measured values and establishes a state-space model based on the measured values. The estimating unit estimates the state-space model to generate an estimated value of the real time solid flow rate. A method for determining a real time solid flow rate of a solid-gas mixture is also presented.

Pneumatic conveying systems refer to the systems for transportation of pulverized solid particles carried by a fluid gas forming a solid-gas mixture from one vessel to another vessel through a pipeline or multiple pipelines. The pneumatic conveying systems have been widely used in various industrial fields such as IGCC (Integrated Gasification Combined Cycle) plants for generating electricity and chemical plants for producing chemicals.
In the pneumatic conveying systems, it is typically necessary to measure the real time solid mass flow rate (shortened as "solid flow rate" hereinafter) for controlling and monitoring purpose. The real time solid flow rate is generally defined as the quantity of mass of solid particles that flow through the cross sectional area of a conveying pipeline of the pneumatic conveying systems per time unit. Currently, there are many ways for determining the real time solid flow rate. One conventional process uses a solid flow rate sensor to directly measure and output the real time solid flow rate. Another process uses multiple sensors that together determine the real time solid flow rate. Some of the multiples sensors are firstly used to determine a mixture flow rate of the solid-gas mixture, and the others are used to determine a gas flow rate. The real time solid flow rate is obtained by subtracting the gas flow rate from the mixture flow rate.
However, during both of these conventional ways for determining the real time solid flow rate, only one measured value of the real time solid flow rate is obtained. As a result, it is very difficult to achieve a reliable real time solid flow rate if any of the sensors is broken or not working properly. Therefore, there is a need to provide improved systems and methods for a reliable real time solid flow rate measurement.

Systems and methods for determining a real time solid flow rate in a solid-gas mixture


This invention concerns novel labeling reactants suitable for labeling of a biospecific binding reactant using solid-phase synthesis. The novel reactants are derivatives of diethylenetriaminepentaacetic acid (DTPA), wherein a suitable group is linked to the DTPA molecule, thus allowing site specific introduction of the ligand of the derivatives to bioactive molecules on solid phase in an oligopeptide synthesizer.

The publications and other materials used herein to illuminate the background of the invention, and in particular, cases to provide additional details respecting the practice, are incorporated by reference.
Because of its excellent metal chelating properties diethylenetriaminepentaacetic acid (DTPA) is one of the most widely used organic ligands in magnetic resonance imaging (MRI) and positron emission tomography (PET) [Aime, S., Botta, M., Fasano, M. and Terrano, E. 1998, Chem. Soc. Rev., 27, 19, Caravan, P., Ellison, J. J., McMurry, T. J. and Lauffer, R. B., 1999, Chem. Rev., 99, 2293, Woods, M., Kovacs, Z. and Sherry, A. D., 2002, J. Supramol. Chem., 2, 1]. Indeed, the first FDA approved contrast agent in clinical use is the Gd3+ DTPA chelate [Runge, V. M., 2000, J. Magn. Res. Imaging, 12, 205.]. The corresponding 111In and 68Ga chelates, in turn, are suitable for PET applications [Anderson, C. J. and Welch, M. J., 1999, Chem. Rev. 99, 2219], while Eu3+, Tb3+, Sm3+ and Dy3+ chelates can be used in applications based on dissosiation enhanced lanthanide fluorescence immunoassay (DELFIA) [PCT WO 03/076939A1]. 99mTc DTPA in turn, is suitable for single positron emission computed tomography (SPECT) [Lorberboym, M., Lampl, Y. and Sadeh, M., 2003, J. Nucl. Med. 44, 1898, Galuska, L., Leovey, A., Szucs-Farkas, Z., Garai, I., Szabo, J., Varga, J. and Nagy, E. V., 2002, Nucl. Med. Commun. 23, 1211]. Bioactive molecules labeled with 111In or 117mSn DTPA may find applications as target-specific radiopharmaceuticals [Volkert, W. A. and Hoffman, T. J., 1999, Chem. Rev. 99, 2269].
In several applications, covalent conjugation of DTPA to bioactive molecules is required. Often, isothiocyanato, N-hydroxysuccinimide or maleimide derivatives of the chelate are used in the labeling the target molecules such as oligonucleotides and oligopeptides. Several bifunctional DTPA derivatives are currently commercially available. Because in all of these cases the labeling reaction is performed in the presence of an excess of an activated label, laborious purification procedures cannot be prevented. Especially, when attachment of several label molecules is needed, purification and characterization of the desired biomolecule conjugate may be extremely difficult.
The purification problems can be avoided by performing the labeling reaction on solid phase. Hence, most of the impurities can be removed by washings when the biomolecule conjugate is still anchored to the solid support, and after release to the solution, only one chromatographic purification is needed. Several such blocks have been published. They include organic dyes [Loshe, J., Nielsen, P. E., Harrit, N. and Dahl, O., 1997, Bioconjugate Chem. 8, 503, McCafferty, D. G., Bishop, B. M., Wall, C. G., Hughes, S. G., Mecklenberg, S. L., Meyer, T. J., and Erickson, D. W., 1995, Tetrahedron, 51, 1093, WO 96/03409, Cuppoletti, A., Cho, Y., Park, J.-C., Strässler, G. and Kool, E. T. 2005, Bioconjugate Chem. 16, 528, Bethelot, T., Lain, G., Latxague, L. and Deleris, G., 2004, J. Fluorescence, 14, 671], derivatives of EDTA [Sluka, J. P., Griffin, J. H., Mack, D. P. and Dervan, P. B. 1990, J. Am. Chem. Soc, 112, 6369, Arya, R. and Gariepy, J. 1991, Bioconjugate Chem., 2, 323, Cuenoud, B. and Schepartz, A. 1991, Tetrahedron, 47, 2535, Rana, T. M., Ban, M. and Hearst, J. E., 1992, Tetrahedron Lett, 33, 4521, Song, A. I. and Rana, T. A., 1997, Bioconjugate Chem., 8, 249, Davies, J. C., Al-Jamri, L., 2002, J. peptide Sci., 8, 663, U.S. Pat. No. 5,637,759], DOTA [Bhorade, R., Weissleder, R., Nakakoshi, T., Moore, A. and Tung, C.-H., 2000, Bioconjugate Chem., 11, 301., Gallazzi, F., Wang, Y., Jia, F., Shenoy, N., Landon, L. A., Hannink, M., Lever, S. Z. and Lewis, M. R. 2003, Bioconjugate Chem., 14, 1083.] and luminescent and non-luminescent lanthanide chelates (U.S. Pat. No. 6,080,839; U.S. Pat. No. 6,949,696; Peuralahti, J., Hakala, H., Mukkala, V.-M., Hurskainen, P., Mulari, O. and Hovinen, J. 2002 Bioconjugate Chem. 13, 876.].
Although DTPA molecule is known for decades, and although reagents for solid phase oligonucleotide derivatization with DTPA has been demonstrated [U.S. Pat. No. 6,949,639], no reactants which allow its direct solid phase conjugation to oligopeptides have been synthesized. The solid phase methods published involve synthesis of oligopeptides, where one ε-amino group of lysine is selectively deprotected while the oligomer is still anchored to the resin [Handl, H. L., Vagner, J., Yamamura, H. I., Hruby, V. J. and Gilles, R. J. 2005, Anal. Biochem. 343, 299, Nagy, I. B., Vagra, I. and Hudecz, F, 2000, Anal. Biochem., 287, 17] Then, an activated DTPA molecule (as an anhydride or an HOBt ester) is coupled to the primary amino function, the oligopeptide is deprotected and converted to the appropriate DTPA chelate. However, this methodology has some drawbacks. First, practically only one DTPA molecule can be introduced. This may be problematic in applications were high detection sensitivity is required. Second, since one of the iminoacetic acid groups is used for conjugation, the resulting chelate is less stable than the parent DTPA molecule [Paul-Roth, C. and Raymond, K. N. 1995, Inorg. Chem. 34, 1408, Li, W. P., Ma, D. S., Higginbotham, C., Hoffman, T., Ketring, A. R., Cutler, C. S, and Jurisson, S. S. 2001, Nucl. Med. Biol. 28, 145.]. This may be a serious problem in vivo applications especially in MRI due to the high toxicity of free Gd(III) ion.
A schematic preparation of stable DTPA derivatives applicable to solid phase peptide incorporation have been proposed [U.S. Pat. No. 5,637,759], but the method of their preparation is challenging due to the carboxyl protecting strategy. There, selective deprotection of a single and specific carboxylic acid group out of six of similar reactivities is required. This problem can be avoided by changing the protecting group strategy, but the synthetic route will be considerably longer [WO 03/011115].


An improved method of tracking a catheter's position within a human body does not rely on x-rays, but instead calculates the position of the catheter's imaging head by analyzing image data. Such an analysis is able to determine the position of the imaging head in 3 dimensional space, relative to an arbitrarily selected reference image. An image is compared with the reference image, correlation data between corresponding points on the two images are gathered, and a correlation loss rate in a particular direction is determined. This correlation loss rate is modeled to an exponential function, which is evaluated to estimate an angle of separation between the image and the reference image. One or more angles of separation are used to determine a position in three dimensional space of the image, relative to the reference image. By repeating this process for a series of images being gathered by a catheter, the position of the catheter can be determined. Additionally, a 3 dimensional map of lumens in the human body can be created.

In the medical arts, catheters are frequently used to diagnose and treat various disorders in a patient, such as clogged or blocked blood vessels. A catheter is introduced into a blood vessel of a patient by, for example, making an incision in the patient over the blood vessel and inserting the catheter into the blood vessel of the patient. A catheter operator such as a physician then maneuvers the catheter through the blood vessels of the patient until the catheter is properly situated to diagnose or treat the disorder. Similar techniques are used to insert catheters into other types of lumens within a patient.
In maneuvering the catheter through the blood vessels or other lumens within the patient, there is a recurrent need to know the location of the catheter within the body space of the patient. Conventional imaging systems create an image of the blood vessel or other lumen which make the lumen appear as a straight tube, and provide no concept of 3-dimensional ("3-D") spatial relationships. In the patient, however, the lumens curve about, and contain branches that branch off at various angles from the lumen. If the position in three dimensions of the imaging head on the catheter can be determined, then through use of three-dimensional imaging software, the true positions and locations of the curves, twists, and turns, as well as the locations of the branch points, of the lumens can be determined. Knowing the true positions allows a more accurate map of the patient to be created, which yields more effective diagnosis and treatment of the patient. For example, gathering accurate 3-D position data allows for an accurate blood flow map and consequent blood flow monitoring and modeling.
Traditionally, X-ray technology has been used to provide a global roadmap of X-ray visible devices, showing their position within the patient. However, an X-ray image, being a two-dimensional projection, can only provide partial information on the 3-D shape of the catheter path. Furthermore, prolonged exposure to X-rays may be harmful to the patient, and it is therefore desirable to avoid such exposures. Thus there is a need for a tracking system which can easily determine the location of a catheter within a patient, without exposing the patient to harmful side effects, and which can be used with a wide variety of catheters or other imaging medical devices.
To overcome the problems inherent with X-ray tracking of catheters, various technologies have arisen which attempt to gather positional information about the location of a catheter within the patient, without the harmful side-effects of X-ray technology. Among such technologies are tracking systems which gather positional information using electromagnetic, optical, mechanical, acoustic, and/or inertial sensing elements. Many of these technologies require the addition of extra elements to the catheter, to allow it to be tracked within the patient.
Therefore there is a need for an improved method of tracking catheters.

Method of catheter tracking using image information


A slot insulator is provided and includes: an annular part; and a plurality of insulated winding parts disposed a circumference of the annular part. Each of the insulated winding parts has an insulated winding holding part and an insertion groove for housing a winding part of a tooth in a stator yoke. The insertion groove opens in one direction along a center axis of the annular plate and opens at both ends of the insertion groove in a radial direction of the annular plate.

FIG. 7 is a perspective view of a general stator yoke in one type of resolver.
A stator yoke 101 includes an outside cylindrical part 102, a winding part 103 facing toward the center from the cylindrical part 102, and a winding holding part 104 provided in a protruding condition at the tip of the winding part 103. A combination of the winding part 103 and the winding holding part 104 is called a tooth 105.
The winding holding part 104 is formed into a rectangular parallelpiped having a quadrate inward surface. The width of a protrusion 107 of a residual obtained by subtracting the width of the winding part 103 from the width of the winding holding part 104 in the circumferential direction is twice as large as a width L1 of a one-sided protrusion 106. Besides, the height of the stator yoke 101 in the center axis direction (direction of the center axis of the outside cylindrical part 102 of the stator yoke 101) is uniformly formed to be H1. The height of the one-sided protrusion 106 is also H1.
In the stator yoke 101 of FIG. 7, a winding (not shown) with insulating coating is wound around the winding part 103 through an insulator (not shown). The illustration of a rotor is omitted. As shown in FIG. 7, a resolver including one stator yoke 101 in which a number of teeth 105 are provided on one cylindrical part 102 and windings are wound around the teeth 105, and one rotor (not shown) is called a simplexed resolver. A multiplexed resolver, for example, an M-plexed resolver is such that basically, the resolver of FIG. 7 is made one resolver unit and M such resolver units are assembled and fixed.
As an insulator provided on the winding part 103, a slot insulator is used.
A pair of slot insulators are mounted (attached) to the stator yoke 101 of FIG. 7 so as to cover the stator yoke 101 from above and below in a direction along the center axis of the stator yoke 101 (see, for example, JP-A-2001-95188, JP-A-2001-169493 and JP-A-2002-171737).
In the case where the slot insulator is used, as compared with a case where a surface of a stator yoke is directly subject to insulating coating, and the winding is provided thereon, there are following merits. Thus, the slot insulator plays an important role at the time of mass production.
(1) In the case of the slot insulator, only a step of direct attachment to the stator yoke is used. On the other hand, in the case where the surface of the stator yoke is subjected to insulating coating, it is necessary to perform plural steps, such as a step of subjecting the stator yoke to the insulating coating and a step of drying it thereafter. Thus, in the case where the slot insulator is used, since the number of insulating process steps of the stator yoke becomes small, the assembling process is short, and manufacturing cost becomes low.
(2) Since the slot insulator is molded out of resin by a metal mold, the unit cost is low.
(3) In the case where an insulating coating material is applied, a gap such as a pinhole is produced in the coating due to uneven coating or the like. On the other hand, since the slot insulator is molded by injecting resin into the metal mold under high pressure, a gap such as a pinhole is not easily produced in the molded resin. Thus, in the slot insulator, insulation between the stator yoke and the coil is more easily ensured.
(4) In the case where an insulating coating material is applied, since the coating material is merely applied to an existing part, the structure can not be changed. On the other hand, since the slot insulator is molded out of resin, the shape and structure of a crossover guide, a winding protection part, a connector, a cover and the like can be freely designed and changed.
Incidentally, as the resolver, in addition to the above structure, a multiplexed (M-plexed) resolver in which plural (arbitrary M) resolver units are stacked into an integral assembly is known.
Also in the multiplexed resolver, although it has been examined to similarly use the slot insulator, this has not been realized.
Hereinafter, for reference, a structure relating to a slot insulator, which was attempted to be adopted for the multiplexed resolver and was not be realized, will be described.
FIG. 8 is a perspective view of a stator yoke in a duplexed resolver.
A stator yoke 1 of the duplexed resolver of FIG. 8 is the stator yoke of the duplexed resolver in which a structure of a simplexed resolver is made one resolver unit, and two such resolver units are stacked to form an integral assembly.
Winding parts 3 are provided on each of the upper and lower stator yokes 1 to be shifted so that they are not overlapped with each other at a common angle position on the circumference. A winding holding part 4 and the winding part 3 constitute a tooth 5.
The number of the teeth 5 and the interval are suitably set in relation to an axial double angle or the like. However, it is preferable that the arrangement of the respective teeth 5 in the circumferential direction is the arrangement in the order corresponding to the order of the resolver units, that is, the stator yokes.
An interval of a height H3 equivalent to the thickness of a cylindrical part 2 is produced between the winding parts 3 of the upper and lower stator yokes 1.
Although the above is an example of the duplexed resolver, the form of a triplexed or higher multiplexed resolver can be similarly constructed.

Slot insulator and multiplexed resolver using same


Performing high-resolution determination of the relative shift of the spectral properties of a biosensor. The shift in the resonance peak of the biosensor is indicative of the amount of material bound to the surface of the biosensor. A preferred biosensor is a Guided Mode Resonant Filter Biosensor (GMRFB). In one aspect of the invention, curve fitting is used to determine the relative location of the spectrum of the unexposed biosensor with respect to those spectra that are altered (e.g., shifted) by the presence of materials bound to the surface of the biosensor. In an alternative embodiment, the cross correlation function is used to detect spectral peak offsets between a reference spectrum and a spectrum measured from an exposed biosensor. In yet another alternative, maximal likelihood estimation techniques are used to determine the spectral shift or offs.

A. Field of the Invention
The present invention relates to biosensors useful for detecting biological material. More specifically, it is directed to a method and device for determining the amount of shift in an optical biosensor's spectral output.
B. Description of the Related Art
With the completion of the sequencing of the human genome, one of the next grand challenges of molecular biology will be to understand how the many protein targets encoded by DNA interact with other proteins, small molecule pharmaceutical candidates, and a large host of enzymes and inhibitors. See e.g., Pandey & Mann, "Proteomics to study genes and genomes," Nature, 405, p. 837-846, 2000; Leigh Anderson et al., "Proteomics: applications in basic and applied biology," Current Opinion in Biotechnology, 11, p. 408-412, 2000; Patterson, "Proteomics: the industrialization of protein chemistry," Current Opinion in Biotechnology, 11, p. 413-418, 2000; MacBeath & Schreiber, "Printing Proteins as Microarrays for High-Throughput Function Determination," Science, 289, p. 1760-1763, 2000; De Wildt et al., "Antibody arrays for high-throughput screening of antibody-antigen interactions," Nature Biotechnology, 18, p. 989-994, 2000. To this end, tools that have the ability to simultaneously quantify many different biomolecular interactions with high sensitivity will find application in pharmaceutical discovery, proteomics, and diagnostics. Further, for these tools to find widespread use, they must be simple to use, inexpensive to own and operate, and applicable to a wide range of analytes that can include, for example, polynucleotides, peptides, small proteins, antibodies, and even entire cells.
For the majority of assays currently performed for genomics, proteomics, pharmaceutical compound screening, and clinical diagnostic applications, fluorescent or colorimetric chemical labels are commonly attached to the molecules under study so they may be readily visualized. Because attachment of a label substantially increases assay complexity and possibly alters the functionality of molecules through conformational modification or epitope blocking, various label-free biosensor technologies have emerged. Label-free detection phenomenologies include measuring changes in mass, microwave transmission line characteristics, microcantilever deflection, or optical density upon a surface that is activated with a receptor molecule with high affinity for a detected molecule. The widespread commercial acceptance of label-free biosensor technologies has been limited by their ability to provide high detection sensitivity and high detection parallelism in a format that is inexpensive to manufacture and package. For example, biosensors fabricated upon semiconductor or glass wafers in batch photolithography/etch/deposition processes are costly to produce and package if the sensor area is to be large enough to contain large numbers of parallel assays. Similarly, the requirement of making electrical connections to individual biosensors in an array poses difficult challenges in terms of package cost and compatibility with exposure of the sensor to fluids.
Biosensors have been developed to detect a variety of biomolecular complexes including oligonucleotides, antibody-antigen interactions, hormone-receptor interactions, and enzyme-substrate interactions. In general, biosensors consist of two components: a highly specific recognition element and a transducer that converts the molecular recognition event into a quantifiable signal. Signal transduction has been accomplished by many methods, including fluorescence, interferometry (Jenison et al., "Interference-based detection of nucleic acid targets on optically coated silicon," Nature Biotechnology, 19, p. 62-65; Lin et al., "A porous silicon-based optical interferometric biosensor," Science, 278, p. 840-843, (1997)), and gravimetry (A. Cunningham, Bioanalytical Sensors, John Wiley & Sons (1998)).
Of the optically-based transduction methods, direct methods that do not require labeling of analytes with fluorescent compounds are of interest due to the relative assay simplicity and ability to study the interaction of small molecules and proteins that are not readily labeled. Direct optical methods include surface plasmon resonance (SPR) (Jordan & Corn, "Surface Plasmon Resonance Imaging Measurements of Electrostatic Biopolymer Adsorption onto Chemically Modified Gold Surfaces," Anal. Chem., 69:1449-1456 (1997), grating couplers (Morhard et al., "Immobilization of antibodies in micropatterns for cell detection by optical diffraction," Sensors and Actuators B, 70, p. 232-242, 2000), ellipsometry (Jin et al., "A biosensor concept based on imaging ellipsometry for visualization of biomolecular interactions," Analytical Biochemistry, 232, p. 69-72, 1995), evanascent wave devices (Huber et al., "Direct optical immunosensing (sensitivity and selectivity)," Sensors and Actuators B, 6, p. 122-126, 1992), and reflectometry (Brecht & Gauglitz, "Optical probes and transducers," Biosensors and Bioelectronics, 10, p. 923-936, 1995). Theoretically predicted detection limits of these detection methods have been determined and experimentally confirmed to be feasible down to diagnostically relevant concentration ranges. However, to date, these methods have yet to yield commercially available high-throughput instruments that can perform high sensitivity assays without any type of label in a format that is readily compatible with the microtiter plate-based or microarray-based infrastructure that is most often used for high-throughput biomolecular interaction analysis. Therefore, there is a need in the art for compositions, biosensors, methods of preparing biosensors and analytical methods that can achieve these goals.
Guided Mode Resonant Filter Biosensors (GMRFBs) have been shown to be one such biosensor well-suited to determining the degree to which biomolecular interactions are taking place near the sensor surface, without resorting to labeling techniques (including fluorescence, calorimetric, and radiolabeling). GMRFBs also excel at monitoring interactions involving small molecules, proteins, cells, microorganisms, and viruses.
Thus, there exists a need for robust methods of determining the relative shifts of the biosensor spectra. Preferably, such an algorithm can detect spectral changes even when the spectral characteristics of the biosensor do not exhibit a clearly defined peak, or if it has multiple peaks.

Method and apparatus for biosensor spectral shift detection


An apparatus and method for adapting to changes in the control topology of a cooperative control system including a plurality of controllers are disclosed. The method is implemented by an actuator or sensor, and includes the steps of selecting one of the controllers as the master controller for one or more state variables of an actuator or sensor, detecting a change in the control topology of the cooperative control system, and reselecting a master controller for the one or more state variables responsive to the change in the control topology.

The present invention relates generally to control systems for process control and, more particularly, to an adaptive control system that can perform control functions in either a centralized or distributed manner depending on system topology.
A centralized control system can be easy to create and maintain because all of the control logic is at a single location. However, the processing requirements can be prohibitive if the central controller is expected to implement complex control algorithms, or to execute multiple control algorithms in parallel. Similarly, the bandwidth requirements to implement complex control algorithms may be prohibitive where data needs to be acquired from many remote sensors. Another drawback is that centralized control systems lack inherent robustness due to possible failure of the centralized controller. To ensure robustness, backup controllers may be required to ensure redundancy, which can make centralized control systems expensive to implement.
A distributed control system is a more complex control system in which multiple controllers share responsibility for certain control functions. In a distributed control system, the control functions may be divided among multiple controllers. One example of this type of control system is a residential heating system having multiple heating zones with heating and cooling elements. Each zone is independently controlled to maintain the temperature within the zone at a desired temperature set point. Each of the controllers is able to set the operating mode and desired temperature for each zone based on user input.
Distributed control systems can be scaled more easily than centralized control systems by adding additional controllers to extend the functionality of the control system. Another advantage of distributed control systems is their inherent redundancy. If one controller fails, the other controllers are still available to perform the control functions of the failed controller.
Typically, a control system is designed to use either centralized control or distributed control before the system components are installed. The choice is made by analyzing the advantages of each type of control given the desired application and system configuration. In order to change from one type of control to another would require the replacement of all of the controllers and many of the controlled components. Reconfiguration of the system would therefore require that operations be halted while the new controllers and other components are installed.

Dynamically adapting to changes in control system topology


A rolling-element bearing cage or a rolling-element bearing cage segment includes a first side ring or a first side ring segment formed from aluminum alloy AA2618, a second side ring or a second side ring segment formed from aluminum alloy AA2618, and at least one bridge formed from aluminum alloy AA2618, the at least one bridge connecting the first side ring to the second side ring or connecting the first side ring segment to the second side ring segment.

Rolling-element bearing cages or rolling-element bearing cage segments are used in different rolling-element bearings to guide rolling elements and space the rolling elements from each other. These cages and cage segments can have a variety of different configurations and can be made from a variety of different materials that are selected, for example, based on the type of bearing in which the cages will be used.
Some rolling-element bearing cages are sometimes manufactured from brass or steel. The acquisition cost of brass is relatively high because one component of brass, namely copper, is a relatively scarce material. In addition, lead is used in many manufacturing processes for rolling-element bearing cages made from brass. Steel bearing cages, on the other hand, are often electroplated with silver. Silver is also expensive, and care must be taken with electroplating processes to avoid injuring workers or releasing potentially hazardous materials into the environment.
This can pose particular challenges for environmental and/or worker protection and increases the cost of brass or coated steel bearing cages.
It is also known to manufacture bearing cages made from certain alloys of aluminum. For example, U.S. Pat. No. 10,215,234, issued to the present applicant and incorporated herein by reference in its entirety, teaches that either aluminum alloy AA6082 or aluminum alloy AA7020 can be used to form bearing cages that are suitable for use in certain environments. These environments do not include high temperature environments, such as those found in gas turbine engines. It is therefore still necessary to use brass or materials other that aluminum for bearing cages that are to be used in high temperature environments.

Lightweight bearing cage for turbine engines and method of forming a lightweight bearing cage


Provided is a data transmission apparatus including a queue management unit to manage at least one queue in which information associated with at least one buffer descriptor (BD) is stored, a scheduler to estimate information to be transmitted among information associated with at least one media access control (MAC) protocol data unit (MPDU) using at least one transmission bitmap (Tx bitmap), a data transmitter to read the estimated information from information associated with a BD indicated in the at least one Tx bitmap, and transmit the read information to a physical layer, and a physical layer management unit to generate information associated with a presentation protocol data unit (PPDU) based on the transmitted information, and transmit the generated information over the air, wherein the at least one BD includes information associated with the at least one MPDU.

1. Field of the Invention
The present invention relates to a method and apparatus for transmitting data based on an available channel bandwidth when a channel access is performed in a wireless local area network (WLAN) system.
2. Description of the Related Art
In a wireless local area network (WLAN), an enhanced distributed channel access (EDCA) protocol and a distributed coordination function (DCF) protocol in which a station (STA) or an access point (AP) independently accesses a channel using a carrier sense multiple access/collision avoidance (CSMA/CA) protocol may be performed in contrast to a mobile communication system.
In a WLAN to which 802.11e standards are applied, when a channel access is started to transmit a frame using an EDCA method, a frame can be transmitted on a primary channel if the primary channel is idle for an arbitration interframe space (AIFS)+a back-off counter time. In order to use a secondary channel having a bandwidth of at least 20 megahertz (MHz) which is a size of a basic bandwidth, the channel access may be performed when a corresponding channel is in an idle state for a period of time greater than or equal to a priority interframe space (PIFS) immediately preceding the expiration of the backoff counter.
In general, the channel access may be performed using a 20/defer mode or a 40/defer mode in 11n of the WLAN. In the 20/defer mode, when a 20 MHz primary channel is available, a frame transmission may be performed. When the 20 MHz primary channel is unavailable, the frame transmission may be on standby until a channel enters the idle state. When an 802.11n STA performs a 40 MHz channel access in the 40/defer mode, a primary channel may be in an idle state during the arbitration interframe space (AIFS)+a back-off count time as described above. When a secondary channel is in an idle state for a period of time greater than or equal to the PIFS immediately preceding the expiration of the backoff counter, a frame transmission may be performed using a bandwidth of 40 MHz. When the secondary channel is not in the idle state for the period of time greater than or equal to the PIFS immediately preceding the expiration of the backoff counter, and the primary channel is available, the frame transmission may not be performed using a bandwidth of 20 MHz although the 20 MHz primary channel is available, and a back-off process may be executed again until the bandwidth of 40 MHz becomes available.
In a case of a 40/20/defer mode, while a utilization rate is relatively low, one of a method of using a bandwidth of 40 MHz, a method of using a bandwidth of 20 MHz, and a method of restarting a back-off may be used based on a channel state.

ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE


A power steering system includes a hydraulic power cylinder, a hydraulic pump for supplying an oil pressure to the hydraulic power cylinder, an electric motor for driving the hydraulic pump, a first detector for detecting a steering assist force to be applied to a steering wheel, a second detector for detecting an operating condition of the electric motor, and a controller. The controller includes a control section for controlling the electric motor based on the required steering assist force detected by the first detector so as to cause the hydraulic pump to produce a required oil pressure, and a determining section for determining based on the operating condition of the electric motor and the required steering assist force detected by the first detector whether or not the power steering system is abnormal.

The present invention relates to a power steering system for generating a steering assist force by means of a hydraulic power cylinder that is operated in accordance with a steering torque of a steering wheel or the like.
This kind of power steering system is disclosed in Unexamined Japanese Patent Publication No. 2002-145087 which is assigned to the same assignee of this application.
The power steering system includes a steering shaft attached to a steering wheel, an output shaft connected to a lower end portion of the steering shaft, a rack and pinion mechanism provided to a lower end portion of the output shaft, a hydraulic power cylinder connected to the rack, a reversible pump for selectively supplying working oil to one of axially opposite first and second oil pressure chambers of the hydraulic power cylinder by way of corresponding one of first and second communication passages, and an electromagnetic valve for selectively opening and closing a bypass passage connecting between the first and second communication passages.
When the steering wheel is steered to the left or right during running of the vehicle, a detecting mechanism detects a steering torque for such a steering operation and supplies a signal by way of a control circuit to the electromagnetic valve to close the same while causing the reversible pump to rotate in the forward direction or in the reverse direction thereby supplying working oil in one of the oil pressure chambers and one of the communication passages to the other of the oil pressure chambers and the other of the communication passages.
Further, the power steering system is provided with an abnormal condition monitoring circuit for monitoring an abnormal condition of an electric motor for driving the reversible pump. The abnormal condition monitoring circuit is configured to determine that the electric motor is abnormal when the rotation speed of the electric motor is zero and causes the electromagnetic valve to open thereby performing a failsafe function. The abnormal condition monitoring circuit can also detect that the reversible pump is abnormal, because the reversible pump is connected to the electric motor.


A nacelle assembly for a turbofan engine includes a forward nacelle portion having an aft edge and defining a bypass duct that transports bypass airflow of the turbofan engine, a translatable sleeve that is translatable aft of the forward nacelle portion, and a variable area fan nozzle (VAFN) airfoil that is movable between a stowed position, a VAFN flow position, and a thrust reverse position. Blocker doors for the thrust position are integrated into the VAFN airfoil.

Typical aircraft turbofan jet engines include an engine core, a nacelle that surrounds the engine core, and a fan that draws in a flow of air that is split into bypass airflow and engine core airflow. The nacelle provides a bypass duct that surrounds the engine core. The bypass airflow is transported through the bypass duct. The nacelle is configured to promote laminar flow of air through the bypass duct. The engine core includes a multi-stage compressor to compress the engine core airflow, a combustor to add thermal energy to the compressed engine core airflow, and a turbine section downstream of the combustor to produce mechanical power from the engine core airflow. The typical turbine section has two and sometimes three turbine stages. The turbine stages are used to drive the compressor and the fan. After exiting from the turbine section; the engine core airflow exits through an exhaust nozzle at the aft end of the engine.
In a turbofan engine, the fan typically produces a majority of the thrust produced by the engine. The bypass airflow can be used to produce reverse thrust typically used during landing. Thrust reversers mounted in the nacelle selectively reverse the direction of the bypass airflow to generate reverse thrust. During normal engine operation, the bypass airflow may or may not be mixed with the exhausted engine core airflow prior to exiting the engine assembly.
Several turbofan engine parameters have a significant impact upon engine performance. Bypass ratio (BPR) is the ratio of the bypass airflow rate to the engine core airflow rate. A high BPR engine (e.g., BPR of 5 or more) typically has better specific fuel consumption (SFC) and is typically quieter than a low BPR engine of equal thrust. In general, a higher BPR results in lower average exhaust velocities and less jet noise at a specific thrust. A turbofan engine's performance is also affected by the engine's fan pressure ratio (FPR). FPR is the ratio of the air pressure at the engine's fan nozzle exit to the pressure of the air entering the fan. A lower FPR results in lower exhaust velocity and higher propulsive efficiency. Reducing an engine's FPR can reach a practical limit, however, as a low FPR may not generate sufficient thrust and may cause engine fan stall, blade flutter, and/or compressor surge under certain operating conditions.
One approach for optimizing the performance of an engine over various flight conditions involves varying the fan nozzle exit area. By selectively varying the fan nozzle's exit area, an engine's bypass flow characteristics can be adjusted to better match a particular flight condition, for example, by optimizing the FPR relative to the particular thrust level being employed. For example, a variable area fan nozzle (VAFN) assembly that forms a rear outer portion of the bypass duct can include an airfoil that is moved aft into a VAFN flow position so as to open an additional bypass flow that exits the nacelle forward of the VAFN assembly. That is, an opening is created between the translatable sleeve and the VAFN airfoil, such that an airflow in the bypass duct is split into a flow that remains in the bypass duct and moves past the airfoil, and a flow that exits the bypass duct through the VAFN opening and over an outer surface of the airfoil.
Turbofan engines typically include a thrust reverser operation, in which the translatable sleeve of the VAFN assembly is moved to expose a cascade array opening, and blocker doors are deployed from in front of the airfoil into the bypass duct. In this thrust reverse position, the blocker doors redirect the airflow in the bypass duct to exit out the cascade array. The VAFN airfoil is typically much too thin and fragile to sustain the airflow loads necessary to divert the bypass airflow to the cascade array. Therefore, the blocker doors are typically deployed from other structures so the blocker doors extend into the bypass duct flow. The VAFN assembly can be selectively positioned anywhere between a stowed position in which no additional bypass exit is formed, a VAFN flow position in which the additional bypass flow exits the bypass duct through the VAFN opening, and a fully deployed position in which the additional bypass exit is open to a maximum extent, such as for thrust reverse operation.
Improving the aerodynamic flow through the bypass duct and around the engine nacelle is a matter of continuous concern for aircraft design. Therefore, it is desirable to locate the VAFN assembly so as to improve aerodynamic flow Improved VAFN assemblies are desired.

Variable area fan nozzle with one or more integrated blocker doors


This invention relates to inhibiting corrosion in systems of condensing hydrocarbons which contain water and chlorides, and, more particularly, in the overhead of crude oil atmospheric pipestills, with blends of amines. Preferred blends are 2-amino-1-methoxypropane, sec-butylamine, n-butylamine, dipropylamine and monoamylamine; 2-amino-1-methoxypropane, sec-butylamine, monoamylamine, n-butylamine and isobutylamine; and sec-butylamine, 2-amino-1-methoxypropane and 3-amino-1-methoxypropane.

Crude oil refineries include an atmospheric pressure pipestill (APS) which fractionates the whole crude oil into various product fractions of different volatility, including gasoline, fuel oil, gas oil, and others. The lower boiling fractions, including naphtha, from which gasoline is derived, are recovered from the overhead fraction. The fractions with intermediate volatility are withdrawn from the tower as sidestreams. Sidestream products include kerosene, jet fuel, diesel fuel, and gas oil. The higher up on the column the sidestream is withdrawn, the more volatile the product. The heaviest components are withdrawn in the tower bottoms stream.
FIG. 1 is a simplified process flow diagram of a typical crude oil atmospheric pipestill unit. The crude is preheated in preheat exchangers against overhead product and then heated up to abut 500.degree. F. to 700.degree. F. in a direct-fired furnace. The feed is then flashed into the atmospheric pipestill which operates at a pressure between one and three atmospheres gauge pressure. Overhead tower temperature ranges typically from 200.degree. F. to 350.degree. F. FIG. 1 shows a two-stage overhead condenser system; alternative systems use one condenser stage. The overhead and sidestream products are cooled and condensed and sent to other units to be processed into final products. The bottoms stream goes to a second distillation tower (not shown) that operates under a vacuum and distills more light products out of the APS bottoms. Steam is added to the bottom of the tower to promote stripping of light products from the bottoms. Also, water is added to the top of the column to wash away soluble salts which often accumulate in the top trays and overhead components. The stripping steam and wash water coming into the system are substantial; the overhead naphtha gas stream coming off the top of the tower typically contains 20 to 40 mole % water.
The corrosion that is the subject of this invention occurs in the overhead components of the atmospheric pipestill which include the top tower trays, the piping that comes off the top of the tower and the reflux lines, the heat exchangers, the condensers and rundown lines, and the distillate drums where the condensed overhead stream is separated into liquid naphtha product and reflux. Materials commonly used in APS overhead trays and components include carbon steel, Monel 400 and 410 stainless steel. Corrosion damage can be very severe, including metal loss severe enough to cause leakage to the external environment and internal heat exchanger leaks, plugging of trays and other internals which interfere with tower operation and control and impair energy efficiency. In addition, corrosion in the APS can cause operating problems in downstream units. Because of the severity of the corrosion, even one day of uncontrolled corrosion can have serious consequences. Corrosion in the overhead exchangers is the major concern.
Corrosion in the overhead system is caused by hydrogen chloride produced by hydrolysis of chloride salts found in crude oil. Crude oils contain salts dissolved in water entrained from the production well and from saltwater picked up during tanker shipment. Generally, the chloride salts are sodium chloride, magnesium chloride, and calcium chloride. Depending on the source of the saltwater, the amount of each salt in the crude can vary considerably. Sodium chloride is stable and does not hydrolyze significantly in the atmospheric crude tower system. HCl is released when MgCl.sub.2 and CaCl.sub.2 are hydrolyzed by water present in crude oil: EQU MgCl.sub.2 +H.sub.2 O=2HCl=MgO EQU CaCl.sub.2 +H.sub.2 O=2HCl=CaO
The chloride salts begin to hydrolyze at temperatures in the range of 350.degree. F. to 450.degree. F., which occur in the preheat exchangers.
The HCl produced in the preheat system does not cause corrosion there because there is no liquid water present. The HCl, however, goes through the pipestill and passes into the overhead gas.
Temperature decreases moving up the tower and into the overhead system. At some point, temperature falls below the dewpoint temperature of the process gas and water condenses on the equipment surfaces in a thin film. This point is called the "initial condensation point" or "ICP." Water continues to condense as the process gas moves downstream and is further cooled. The overhead gas is totally condensed in the overhead condensers, is accumulated in a condensate drum, and is removed from the bottom boot of the condensate drum. Operators usually maintain the temperature at the top of the tower at least 30.degree. F. to 40.degree. F. above the water dewpoint to avoid corrosion in the top trays. The trend, however, is to reduce tower top temperature to improve recovery of naphtha, and this drives the dewpoint down into the tower. Accordingly, the water dewpoint usually occurs in the overhead system, but it can occur within the distillation tower if the composition of the process streams and tower operating conditions combine to raise the dewpoint above the top tower temperature. Spot or "shock condensation" can occur upstream of the ICP if there are cold spots on upstream surfaces where, for example, insulation is worn and the tower shell is exposed to cold wet weather or at cold spots on heat exchanger tubes in the condensers. Accordingly, the locations where condensation initially occurs are uncertain and changeable as operating and ambient conditions change.
The ICP and shock condensation points are important because that is where chloride concentration is highest and pH lowest. Initial condensates, if untreated, exhibit pH's as low as one or even fractional pH's, and the danger of catastrophic corrosion at these points is great. Corrosion by acidic chloride condensates is driven by the hydrogen ion concentration (pH) via the reaction: EQU Fe+2HCl=FeCl.sub.2 (soluble)+H.sub.2
Hydrogen sulfide, which is formed in the pipestill from organic sulfur compounds in crude oil, also dissolves in water condensate and accelerates acidic chloride corrosion. Although the source of the corrosive attack is HCl, the product of corrosion is iron sulfide, not iron chloride. Iron sulfide is precipitated by the reaction between H.sub.2 S and soluble iron chlorides from the corrosion reaction between HCl and the steel equipment, thus liberating additional HCl. EQU FeCl.sub.2 +H.sub.2 S=FeS+2HCl
Note that the HCl is regenerated by the H.sub.2 S. Hydrochloric acid thus acts as a catalyst for formation of iron sulfide, and is not consumed.
The APS streams also contain low molecular weight carboxylic acids (acetic, propionic, butyric acids) which increase corrosion at the ICP and subsequent condensation zone.
The water coming overhead from the tower is totally condensed in the overhead exchangers and is accumulated in the condensate drum. The bulk water condensate contains chlorides, sulfides, and ammonia, and is mildly corrosive. Experience indicates that bulk water condensate should be maintained in the pH range of about 5 to 6.5 to minimize corrosion in the system. pH in the bulk condensate is controlled by adding a neutralizer, such as ammonia, to the overhead system.
In addition to being subject to severe corrosion at the ICP and points of shock condensation, APS systems are also vulnerable to severe corrosion upstream of the ICP where ammonium chloride precipitates as a solid out of the gas phase onto internal surfaces. Ammonium chloride is formed in the system by the reaction between ammonia and HCl. Ammonia comes into the pipestill in the incoming crude oil and other incoming process streams, and is often intentionally added to neutralize HCl in the overhead bulk sour water condensate. At equilibrium, the partial pressure of ammonium chloride over the internal surface on which ammonium chloride has deposited equals the vapor pressure of ammonium chloride at the temperature of the internal surface. FIG. 3 is a graph of vapor pressure of ammonium chloride versus temperature. If the partial pressure of ammonium chloride above the internal surface exceeds the vapor/equilibrium pressure, then ammonium chloride will precipitate on the surface and accumulate.
Ammonium chloride deposits are hygroscopic and, when exposed to wet process gas streams flowing by, absorb moisture, forming a wet paste with a pH of about 3.5, which is a highly corrosive enviromnment. Ammonium chloride deposits are only a problem if they form above the water dewpoint. If they form below the dewpoint where water is condensing profusely along with the ammonium chloride, then the deposits will be washed away. But, if ammo nium chloride condenses above the dewpoint and water is not condensing on these surfaces, ammonium chloride deposits will not be washed away by water and the deposits will build up.
APS corrosion problems are on the increase. The increased corrosion is attributed to several causes. Salt content of crude oils now being run in refineries have increased, generating more chlorides. Also, crudes are heavier, which makes them harder to desalt. Ammonia concentrations in pipestills have risen because of refinery operating changes in other units. Also, refiners are running lower tower top temperatures to increase yields of profitable distillate fuels, such as jet fuel, and also to raise energy efficiency of the operation. Reducing top temperature often brings the water dewpoint upstream from the overhead equipment into the tower.
The first defense against overhead corrosion is crude oil desalting. A desalter is shown in the flow plan of FIG. 1. In the desalter, crude is mixed with about 5% water, which dissolves the salt. The salty water is separated from the crude and discarded. However, oil/water emulsions form that are difficult to break. Chemical demulsifiers are added to break the emulsion. Electrical devises which charge the water drops to enhance separation are also used. Up to about 90% of the salt can be removed with a single stage of water washing and separation. Salt removal effectiveness depends on the nature of the crude. Heavier oils are more difficult to desalt than light crudes. A second wash state is commonly used to remove additional salt.
Caustic (NaOH) is commonly injected into the crude downstream of the desalter to reduce chlorides in the pipestill overhead system. The caustic reacts with the magnesium and calcium chloride to form sodium chloride, which is more thermally stable and so will not hydrolyze. However, caustic treat must be limited since caustic causes furnace coking and induces operating problems in downstream units. New catalysts being used in downstream units in response to environmental control demands being imposed on refineries are poisoned by caustic. In most instances, it is impractical to remove enough salt with desalters and/or caustic addition to completely eliminate HCl corrosion. Moreover, operating upsets in the pretreat systems occur, which periodically introduce large doses of chlorides.
Accordingly, chloride neutralizers are added to the APS system to inhibit corrosion. The most common neutralizer is ammonia. It can be added as ammonia gas or as an aqueous solution usually into the overhead lines between the pipestill and the overhead condensers. ammonia is effective for increasing the pH of the overhead bulk water condensate to within a safe pH range, which is abut 5.5 to 6.5. But, ammonia does not neutralize condensate acidity at the ICP and shockpoint environs where corrosion is most virulent. This is because ammonia is volatile and ammonium chloride unstable in the water phase at ICP and shockpoint temperatures.
These concepts can be visualized by referring to FIG. 2, which is a graph of temperature versus pH of condensate for a typical APS system. The pH at the initial point of condensation which, in this example, occurs at 230.degree. F., is below 1. pH rises to about 4 moving downstream along the curve left to right to 180.degree. F. where the water is totally condensed. Obviously, this situation is unacceptable since the system internals will experience catastrophic corrosion at the low pH's indicated.
Curve II is for a system protected with ammonia. Note that ammonia protects the system well upstream of the zone of initial condensation, but provides no pH elevation at the virulent zone of initial condensation.
Curve III is the pH curve required to adequately protect the system. Note that the pH is uniformly elevated into the corrosion safe 5 to 6 pH range across the entire condensation zone.
Current commercial practice to protect APS units from corrosion is to inject organic amines into the APS overhead system. The amines used are volatile, so they appear in the gas phase upstream of the ICP where they react with some of the HCl in the gas stream before the HCl reaches the condensation zone. However, there may not be sufficient time and contact in the gas phase to neutralize all the HCl upstream of the condensation point. Accordingly, some of the HCl must be neutralized in the aqueous solution after it is absorbed by the condensate water phase.
Suitable neutralization amines include morpholine, methoxypropylamine, ethylenediamine, monoethanolamine, and dimethylethanolamine. APS overhead neutralizing amines are usually added as aqueous solutions, typically about 50% water. The most common injection points are in the overhead lines between the pipestill and the overhead exchangers, the sidestream inlets to the tower, and directly to the crude oil coming into the tower. Common practice is to control the neutralizer addition rate to maintain the pH of bulk water condensate in the separator drums to between 5.5 and 6.5, and preferably 5.5 to 6.0. If the proper amines are selected, adequate pH elevation is achieved over the entire condensation zone when the pH of the bulk condensate is maintained over 5.5.
Filming inhibitors are usually injected into the overhead system to further reduce corrosion in the upstream sections of the overhead system. They are proprietary formulations, usually oil soluble, which protect equipment by forming a barrier on the steel surface. Film inhibitors are effective in the downstream sections of the condencing zone where chloride concentrations are moderate, but are not effective at ICP and shock points.
A disadvantage of using amines to control corrosion in condensing systems containing chlorides is that the amines react with chlorides to form hydrochloride salts which deposit on internal surfaces. The salts deposit on surfaces at temperatures above the water dewpoint, upstream of the condensation zone, often in the top trays of the system tower. The salt deposits are hygroscopic and absorb moisture from the process gas to form highly corrosive viscous fluid or paste which induce underdeposit corrosion.
Amine salts are not a problem if they deposit in the condensation zone because they are continuously washed away by condensate. Some operators mitigate the problem by periodically washing the overhead system with water to remove deposits.
Instances of salt deposition above the dewpoint in pipestills are increasing because refineries are running heavier and dirtier crudes, which generate larger amounts of chlorides and, to protect their units, operators are increasing neutralizer amine treat rates. Ammonium chloride deposition above the dewpoint is also increasing because ammonia in crude is increasing. Accordingly, there is a need in the refining industry for new technology to inhibit corrosion in wet hydrocarbon condensing systems containing chlorides which does not compound the problem by inducing troublesome salt deposits above the dewpoint. The present invention is a novel process which accomplishes this objective.
Corrosion control in crude distillation units is discussed in two papers which were presented to the National Association of Corrosion Engineers: Rue, J. R. and Naeger, D. P., "Advances in Crude Unit Corrosion Control," Corrosion '87, Paper No. 199, National Association of Corrosion Engineers, Houston, Tex.:, and Rue, J. R., and Naeger, D. P., "Cold Tower Aqueous Corrosion: Causes and Control," Paper No. 211, National Association of Corrosion Engineers, Corrosion '90, Las Vegas, Nev. The papers discuss the amine salt deposition problem, which is the focus of the present invention, but the authors advocate techniques which minimize and suppress chloride hydrolysis to solve the problem.
The amine salt deposition problem is addressed in U.S. Pat. No. 5,211,840, which teaches that amine salt deposition can be avoided by using weak base amines, those having pKa between 5 and 8. The inventors discovered that hydrochloride salts of weak amines have less propensity to deposit on tower internals than salts of strong amines and ammonium chloride. The patent says the amines may be added to the distillation unit at any point in the overhead system prior to the location where the condensate forms.
Specifically, the patent teaches:
that it is necessary to add a sufficient amount of the neutralizing amine compound to neutralize the acidic corrosion causing species. It is desirable that the neutralizing amine be capable of raising the pH of the initial condensate to 4.0 or greater. The amount of neutralizing amine compound required to achieve this objective is an amount sufficient to maintain a concentration of between 0.1 and 1,000 ppm. based on the total overhead volume. The precise neutralizing amount will vary depending upon the concentration of chlorides or other corrosive species. PA1 blending a minor amount of highly basic amine with a low pka amine. These blends would be advantageous to use in systems where a sub-neutralizing quantity of highly basic amine can be used without causing above the water dewpoint corrosion and/or fouling problems. PA1 that certain amines having the following formula corresponding to Formula 1 below: EQU R--O--(CH.sub.2)nNH.sub.2 Formula 1
The patent also teaches:
The patent cites 4-picoline and 3-picoline as examples of low pka amines, and methoxypropylamine and ethanolamine as highly basic amines. The patent defines minor amounts to be less than 20% of treatment.
The amine salt deposition problem is addressed in U.S. Pat. No. 4,430,196, which teaches the use of a member or members selected from the group of dimethylaminoethanol and dimethylisopropanolamine.
The amine salt deposition problem is also addressed in U.S. Pat. No. 4,806,229, which teaches:
wherein n is 2 or 3 and R is a lower alkyl radical of not more than 4 carbon atoms, when added to a crude oil charge or at various other points in the system, effectively eliminates and/or controls corrosion that ordinarily occurs at the point of initial condensation of water vapors within or leaving the distilling unit. Illustrative of compounds falling within Formula 1 are methoxypropylamine, ethoxypropylamine, methoxyethylamine, and the like. The most preferred compound is methoxypropylamine.
State of the art techniques and equipment for injecting and controlling addition of neutralizing agents to the APS system and other refinery distillation towers are described in U.S. Pat. No. 5,302,253, which is incorporated herein by reference. In one embodiment of the disclosure, the pH of condensate removed from the tower system is continuously measured with a standard pH electrode. The pH signal is sent to a controller, which compares it with the pH setpoint, and the controller throttles the pumping rate of the amine pump used to inject neutralizer into the APS system to bring the pH of the bulk condensate reading to the setpoint. Preferably, the condensate is bulk water condensate taken from the overhead accumulator drum water boot, but condensate can be removed from some intermediate condensation point in the tower overhead system. A corrosion safe range for bulk water condensate pH is typically 5 to 6.5.
U.S. Pat. Nos. 4,335,072 and 4,599,217 describe devices which attach to the treated system and monitor corrosion rate and treatment. The devices are termed "Overhead Corrosion Simulators" ("OCS"). These patents are incorporated herein by Reference. An Overhead Corrosion Simulator is a small condenser heat exchanger cooled with flowing cooling water which is installed onto the pipestill overhead system such that it withdraws a small overhead gas slipstream from the pipestill overhead. The slipstream is withdrawn from a point sufficiently upstream where the tower temperature is above the initial point of water condensation so that no water condensation has yet occurred. The OCS cools the overhead stream in small temperature increments from initial condensation through total condensation. The condensate at each stage of cooling is continuously collected and rate of corrosion and/or pH are continually monitored using conventional instrumentation techniques. Using the OCS, corrosion rates and pH, at each point in the system where water condensation is occurring, are simulated and continually monitored and conditions at the all important point of initial condensation continually observed even if the point shifts upstream or downstream in the APS overhead system.
Various amines are known for the treatment of hydrocarbon streams. For example, a process for substantially neutralizing the volatile acid gases and water present in the condensate of a distilling petroleum product, which comprises treating the distilling product prior to the condensation thereof with at least one amine in U.S. Pat. No. 4,806,229. A corrosion control method utilizing methoxypropylamine in petrochemical process units is disclosed in U.S. Pat. No.4,229,284. A method for neutralizing acidic components in petroleum refining units utilizing an alkoxyalkylamine is disclosed in U.S. Pat. No. 4,062,764. The use of at least one neutralizing amine for the prevention of fouling caused by amine chloride salt deposits is disclosed in U.S. Pat. No. 5,211,840. Certain amines as neutralizing agents in petroleum refining units are disclosed in U.S. Pat. No.4,430,196 and 3,779,905. Additionally, the use of2-amino-1-methoxypropane as a neutralizing amine in refinery processes is disclosed in U.S. Pat. No. 5,641,396. Though certain amines or blends have been disclosed, there remains a need in the refining industry for new technology for more efficiently inhibiting corrosion in wet hydrocarbon condensing systems containing chlorides while not compounding the problem by inducing troublesome salt deposits above the dewpoint. The present invention represents three novel blends which accomplish this objective.

Amine blend neutralizers for refinery process corrosion


An imaging lens includes a first lens group having a positive refractive power, an aperture stop, and a second lens group having a positive refractive power, which are disposed in order from an object. The first lens group has a first lens component having a negative refractive power and a second lens component having a positive refractive power, which are disposed in order from the object, and conditions expressed by the expressions 0.12<f/f1<0.47 and 0.016<D12/f<0.079 are satisfied, when f1 is a focal length of the first lens group, f is a focal length of the imaging lens, and D12 is an air distance between the first lens component and the second lens component of the first lens group.

As a compact lens used for a photograph camera and video camera, having about a 50° angle of view, and a relatively bright F number, an imaging lens having a first lens group comprised of a negative lens and a positive lens, and a second lens group comprised of a stop, a cemented lens of a negative lens and a positive lens, and a positive lens, have been available (e.g. Japanese Patent Application Laid-Open No. H9-189856).
On the other hand, along with the recent demand for smaller, slimmer and lighter cameras, holding a camera during actual use is becoming difficult, and shooting errors due to blur caused by a motion of the camera are increasing. A slight blur of a camera generated during shooting (e.g. blur of a camera generated when the user presses a release button) causes an image blur during exposure, and deteriorates the image quality.
To solve this problem, a known method for correcting an image blur is combining a detection system for detecting the blur caused by motion of a camera, a computing system to control a shift lens group according to a value which is output from the detection system, and a drive system for shifting the shift lens group, as an optical system which can shift an image of the imaging lens, and driving the shift lens group so as to compensate for the image blur caused by the motion of a camera.

Imaging lens, optical apparatus and method for forming image using this imaging lens


A substrate processing system to process a substrate includes a sensor to generate sensed values of a parameter of the substrate processing system. An actuator adjusts the parameter of the substrate processing system. A controller communicates with the sensor and the actuator and is configured to process a first substrate using the sensed values to adjust control values for controlling the actuator without feedforward control during a process. The sensed values are delayed and cause instability in the parameter. The controller is further configured to automatically calibrate feedforward values for processing a second substrate based on the sensed values and the control values and process the second substrate while controlling the actuator using the feedforward values.

The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Substrate processing systems may be used to perform etching, deposition, cleaning, and/or other treatment of substrates such as semiconductor wafers. During processing, a substrate is arranged on a substrate support, such as a pedestal, an electrostatic chuck (ESC), etc. in a processing chamber of the substrate processing system. A process gas mixture is introduced into the processing chamber to treat the substrate. In some examples, plasma may be struck to enhance chemical reactions within the processing chamber. An RF bias may be supplied to the substrate support to control ion energy.
A controller that is used to run the process may receive feedback values relating to chamber parameters from one or more sensors. For example, the controller may receive feedback values from one or more temperature or pressure sensors. The controller makes adjustments to the process based on a recipe and controls the actuator based on the feedback values from the sensors. Examples of actuators include heaters, valves, RF generators, pumps, etc. In some examples, the feedback values provided by the sensors may be delayed. As a result, the controller is unable to adjust the actuator in time to avoid departure from a desired operating state.
While feedforward control can be used, it can be difficult to implement. The feedforward values are manually determined and tested for each process step and for each process. For example, feedforward values for each new or modified recipe may take on the order of a day of work to determine.
Alternately, higher cost sensors may be used to sense the chamber parameter in real time. For example, an optical sensor can be used to measure the pedestal temperature without a delay. However, optical sensors and their supporting electronics are expensive. Furthermore if the optical sensors are used, the temperature sensor is also typically still required for redundancy.

Auto-calibrated process independent feedforward control for processing substrates


A circuit arrangement having the function of preventing over-voltage damage which is structured by special copper foil or conductive wires and applies the burst absorption principle to form a short circuit from the input end and the output end of a circuit when the circuit is subject to an over-voltage or a transient electrical strike, so as to protect the electronic elements within the area of the circuit. The method can be put into application in a transformer, a switching power supply, an electronic computer, a solid-state relay and other similar electronic equipment. The arrangement of the present invention has undergone a number of high voltage and electrical striking tests with more than satisfactory results and is suitable for use in industries.

The present invention relates to an arrangement of the components in a circuit, in order to prevent the electronic components in the circuit from being damaged by an over-voltage. The arrangement is especially suitable for high electric power devices requiring a high voltage processing operation or usually having to be installed outdoors so as to protect the component elements thereof.
Previously, the practice of preventing over-voltage damage was usually conducted using a photo coupler (such as photo-transistor coupler and photo-thyristor coupler etc.) as a coupling element between an input terminal and an output terminal of an electronic circuit for the purpose of isolating the input terminal and the output terminal. Generally, the breakdown voltage of the optimal photo coupler recognized in the art is approximately up to 5,000 VAC. Therefore, devices having such couplers are free of any problems as long as the over-voltage thereof does not exceed 5,000 VAC. However, once a high voltage over 5,000 VAC appears across the input and the output terminals of the circuit, the high voltage will go from the input (or output) side to the output (or input) side through the photo-thyristor and the electronic elements of the circuit. In such case, the photo-thyristor and the electronic elements will be damaged, and the entire printed circuit board may even be burned out. It is clear that over-voltage protection between the input terminal and the output terminal of a circuit is of vital importance. In view of the fact that the maximum breakdown voltage of existing photo-couplers is no more than 5,000 VAC, the present invention develops a specific circuit arrangement based on a series of experiments.

Arrangement of an over-voltage protection circuit


A modification kit for the addition of an auxiliary battery charge management system for a marine or land vehicle having a starting battery and an auxiliary battery system. The kit includes a single pole breaker, a normally-on relay, and a two-way toggle switch. The single pole breaker is inserted in a circuit of the auxiliary battery system, and the normally-on relay and the toggle switch are inserted in the starting battery circuit of the vehicle to provide a dual mode charging system adapted to manual and automatic power regeneration of the starting battery and the auxiliary battery system.

1. Field of the Invention
The present invention is directed primarily to a dual mode battery charge managing system for land and marine vehicles. The system is dual mode in that it can be operated manually or automatically. The modification kit is inexpensive and readily installed by any owner. The present invention can be utilized for marine vehicles, e.g., fishing boats, pontoon boats, pleasure boats, etc., for operating live bait wells, as well as for non-marine vehicles such as hydraulic dump trailers and wrecker machines that must maintain auxiliary batteries for purposes such as for starting (boosting) the engine or running other electronic components, e.g., radio and the like.
2. Description of Related Art
The prior art describes various boat battery charging systems. These systems are expensive to install and to maintain. There is a need for a simpler and more economical installation which a boat owner can readily install, and still have peace of mind that the boat batteries are always charged in an operative condition. The prior art will be discussed in the order of perceived relevance to the present invention.
U.S. Pat. Nos. 5,448,152 and 5,225,761 issued respectively on Sep. 5, 1995 and Jul. 6, 1993, to Charles D. Albright describe similar battery management systems differing only in the source of the DC voltage, wherein an inboard boat engine charges a plurality of batteries arranged in parallel for an electric boat motor. In the earlier patent the DC voltage is derived from the alternating current component of the charging signal, whereas in the later patent the time-varying component of the charging signal is sensed. In these completely automated systems, there is automatic charging of the auxiliary batteries while the boat engine is operating, and automatic switching out of the charging process when the boat engine is inoperative. Two 12 volt auxiliary batteries are coupled in parallel with the main battery to receive charging, and the auxiliary batteries provide 24 volts for the trolling motor by loading in series. The present invention applies only to the conversion of an outboard motor-electric motor system or a new installation thereof, and does not require a completely automatic system as described by Albright, which system is expensive to install and difficult to repair when trouble arises due to rough weather, for example.
U.S. Pat. No. 5,233,282 issued on Aug. 3, 1993, to Takashi Iwashita describes a battery system for an inboard internal combustion engine that drives a generator and electric motors. A pair of contact relays, responsive to the main switch, are used to adjust the circuitry of the battery system so that the actuating batteries are either connected in parallel in the charging state or connected in series in the actuating state. The instant invention is not directed to an inboard gas engine with generators for charging.
U.S. Pat. No. 4,081,738 issued on Mar. 28, 1978, to William G. Roller describes a plural battery control apparatus for controlling trolling motor batteries. A three-position switch couples two batteries into a circuit and switches the batteries into a parallel or series configuration across a load. The batteries are switchable for application of a remote charging device or for higher voltage (series) or lower voltage (parallel) use. The voltage condition of the batteries is constantly monitored. The present invention requires only a two-way switch for operation of the charging system for batteries for the outboard motor and the electric motor.
U.S. Pat. No. 5,418,444 issued on May 23, 1995, to Gary L. Cook et al. describes an automatic battery charge and discharge control system for boats having an inboard gas engine and auxiliary batteries running on 12 volts or multiples thereof. When the engine ignition is turned on, the main battery is connected in parallel during charging, and when turned off isolates the main battery from the auxiliary batteries, allowing the auxiliary batteries to discharge without affecting the voltage potential of the main battery. An override of the ignition control when the ignition control is turned off allows the main battery to be placed in parallel with the auxiliary batteries and to be charged by the charging circuit. The charger circuit can sense the charge potentials of the main and auxiliary batteries so that charging of either the main battery or the auxiliary batteries can be automatically stopped when fully charged. This automatic system is applicable only to an inboard gas engine and would not operate with an outboard engine lacking a voltage regulator and an alternator.
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus, an economical boat battery charging system solving the aforementioned problems for an outboard gas engine and auxiliary electric motors is desired.