description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
[0001] The present invention relates to a sensor assembly for downhole use in a wellbore. This invention also relates to a new pack-off assembly housing the sensor.
[0002] Downhole sensors are used to measure pressure, flow and/or other conditions in a well. Often, the sensor must be positioned near the point of production and is subjected to extreme temperatures, pressures, vibrations, and other abuses. In addition, because the downhole environment is a high pressure environment, it is highly desired to pressure test the sensor assembly after fabrication and prior to deploying the assembly downhole.
[0003] The sensor of the current disclosure provides not only for the capability to conduct pressure testing of the downhole sensor assembly prior to deployment in the downhole environment, but also protects the sensor so as to limit damage during deployment.
SUMMARY OF THE INVENTION
[0004] The downhole sensor assembly is attached to a tubing string that is disposed in a wellbore that may be cased or uncased. In one embodiment, a sensor assembly for use in a wellbore is provided. The sensor assembly is able to be attached to a tubing string that is lowered into the wellbore. The sensor assembly includes a pack-off pipe, a sensor sleeve, and a sensor. The sensor sleeve has a first end and a second end. The first end of the sensor sleeve is adapted to be exposed to the wellbore, and has an internally threaded surface. The internally threaded surface is for receiving a test device. The sensor is for sensing a parameter in the wellbore. The sensor is secured to the second end of the sensor sleeve and is positioned within the pack-off pipe.
[0005] In another embodiment, a downhole sensor assembly for use in a wellbore is provided. The downhole sensor includes a pipe, a tubular sleeve and a sensor. The pipe is adapted to be secured to a tubing string and lowered into the wellbore. The pipe has a first end and a second end. The tubular sleeve has a first end and a second end. The tubular sleeve is positioned within the pipe. The tubular sleeve first end is exposed to the wellbore and is capable of receiving a test device. The sensor is for sensing a parameter in the wellbore. The sensor is secured to the second end of the tubular sleeve and is positioned within the pipe. The sensor and pipe form an annulus therebetween.
[0006] In yet another embodiment, a downhole sensor assembly for use in a wellbore is provided. The downhole sensor assembly comprises a pack-off pipe, a sensor sleeve, a test chamber and a sensor. The sensor sleeve is positioned in the pack-off pipe. The sensor sleeve has a first set of internal mounting threads positioned near a first end of the sensor sleeve. The sensor sleeve has a second set of internal mounting threads positioned near a second end of the sensor sleeve. The first set of mounting threads in the sensor sleeve is adapted to receive a test device. The test chamber is positioned in the sensor sleeve between the first and second sets of internal mounting threads. The sensor is for sensing a parameter in the wellbore. The sensor is secured to the second set of mounting threads and is positioned in the pack-off pipe.
[0007] The objects, features and advantages of the present invention will be readily apparent to those skilled in the art upon a reading of the description of preferred embodiments when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 depicts a schematic view of a sensor assembly disposed in a wellbore.
[0009] FIG. 2 depicts a side section view of a sensor assembly.
[0010] FIG. 3 depicts a section view of a sensor sleeve.
[0011] FIG. 4 depicts an exploded view of a sensor assembly.
DETAILED DESCRIPTION
[0012] Referring to the drawings, a downhole sensor assembly is illustrated and generally designated by the numeral 10 , and the components thereof are designed to be associated with downhole tubing string 12 .
[0013] Downhole sensor assembly 10 shown in FIG. 1 is secured to a tubing string 12 . Tubing string 12 may be disposed with or without tools attached thereto. Straps 14 are shown securing downhole sensor assembly 10 to tubing string 12 . However, other connective devices or other means to externally connect downhole sensor assembly 10 to tubing string 12 may be used in place of straps 14 . In FIG. 1 , tubing string 12 is disposed inside a casing 16 of wellbore 18 . However, tubing string 12 may be disposed in wellbore 18 without casing 16 .
[0014] FIGS. 2-4 show downhole sensor assembly 10 in greater detail. Downhole sensor assembly 10 comprises a pack-off pipe 20 having tubular sensor sleeve 22 and sensor 24 positioned therein. Pack-off pipe 20 has pipe first end 26 , pipe second end 28 , and pipe inner surface 30 . Preferably, tubular sensor sleeve 22 is positioned at, or near, pipe first end 26 .
[0015] Sensor sleeve 22 , depicted in FIGS. 2 and 3 , is tubular shaped and has sleeve first end 32 , or outer end 32 . Sensor sleeve 22 has a first set of internal mounting threads 34 axially positioned thereon, which are preferably, progressively tapered radially inward from the sleeve first end 32 .
[0016] Tubular sensor sleeve 22 also has sleeve second end 38 , or inner end 38 , which is adapted to receive and secure sensor 24 . As shown in FIGS. 2 and 3 , sensor sleeve 22 has a second set of internal mounting threads 40 internally positioned thereon and adjacent to sensor 24 . Second set of internal mounting threads 40 are for connecting to sensor 24 . Although second set of internal mounting threads 40 are depicted in FIGS. 2 and 3 , second sleeve end 38 may employ any connective mechanism that will secure sensor 24 in tubular sensor sleeve 22 .
[0017] Sensor 24 , as shown in FIGS. 2 and 4 , is a pressure transducer. However, it is understood that any type of sensor device that is capable of detecting a particular parameter of the downhole environment may be utilized in downhole sensor assembly 10 . For example, it is known that the pressure transducer shown in FIGS. 2 and 4 can be replaced with a conductive sensor capable of measuring temperature or chemical composition. With regards to a pressure transducer, sensor 24 is able to detect the pressure in wellbore 18 , as sleeve first end 32 is open to the wellbore.
[0018] Test chamber 42 is positioned between sleeve first end 32 and sleeve second end 38 . Test chamber 42 is sometime referred to as a gap or space. Test chamber 42 may be threaded or unthreaded, as long as there is a chamber or space for testing the performance of sensor 24 . Test chamber 42 is a test chamber positioned to test sensor 24 after assembly, and prior to deployment of sensor assembly 10 into wellbore 18 .
[0019] Sensor 24 has sleeve exterior surface 44 as shown in FIGS. 2 and 3 . Sleeve exterior surface 44 is adapted to sealingly engage pipe inner surface 30 when assembled. The means of sealingly engaging sleeve exterior surface 44 with pipe inner surface 30 is common in the downhole test equipment assembly process, and thus not discussed herein. When assembled, sleeve first end 32 and pipe first end 26 are preferably planarly flush with each other.
[0020] First set of internal mounting threads 34 are adapted to receive a compatible piece of test equipment (not shown). In the preferred embodiment, for the example pressure transducer, the test equipment is adapted to provide pressure testing of sensor 24 after complete assembly of sensor assembly 10 , and again, prior to insertion into wellbore 18 . The pressure test equipment may be threaded into first set of internal mounting threads 34 and then a pressure applied within test chamber 42 . Sensor 24 may therefore be tested after sensor assembly 10 is fully assembled, and prior to deployment in wellbore 18 . Any pressure test equipment threaded into first set of internal mounting threads 34 will be removed prior to deployment so that sensor 24 will sense pressure in wellbore 18 through the open sleeve first end 32 of sensor sleeve 22 . For other types of sensors, the appropriate type of test equipment may also be attached and utilized to test that other type of sensor after assembly and prior to insertion. A non-limiting example of another type of sensor test equipment might be a temperature sensor test equipment device.
[0021] As shown, in FIGS. 2 and 4 , downhole sensor assembly 10 also includes sensor cable 46 connected to connecting cables 48 of sensor 24 with connectors 50 . Sensor cable 46 is positioned through the center of pack-off end 52 .
[0022] When sensor 24 is secured, sensor 24 and pack-off pipe 20 form annulus 54 , which is a cavity between sensor 24 and pipe inner surface 30 . FIG. 2 shows sensor 24 positioned within pack-off pipe 20 and surrounded by annulus 54 . Annulus 54 is preferably substantially filled with a fluid compound capable of providing increased stability of downhole sensor assembly 10 , and to further secure sensor 24 within pack-off pipe 20 . The fluid compound is preferably a thermosetting polymer, but it may be any pourable or injectable compound capable of securing sensor 24 in pack-off pipe 20 with a water tight seal. Preferably, the thermosetting polymer securing sensor 24 does not interfere with the function of sensor 24 . During the assembly process, pack-off end 52 may be secured to pipe second end 28 of pack-off pipe 20 by threads, glue, welding or other means known to those skilled in the art. Once pack-off end 52 is secured, it is preferred to apply shrink wrap 56 over pack-off end 52 and pipe second end 28 to further seal downhole sensor assembly 10 .
[0023] Downhole sensor assembly 10 provides advantages over other sensor assemblies in that it is protected from the environment and from impact damage. In addition, sensor 24 can be tested not only prior to the insertion into pack-off pipe 20 , but also immediately prior to insertion into wellbore 18 . Testing is accomplished by connecting the pressure test equipment to sensor sleeve 22 as described herein. Once in a wellbore, parameters, e.g. pressure, are sent via a signal to the surface through sensor cable 46 .
[0024] The current invention also provides methods for assembling and testing sensor 24 of downhole sensor assembly 10 . The method for assembling downhole sensor assembly 10 provides a sensor sleeve 22 that is positioned within pack-off pipe 20 at, or near, pipe first end 26 . Sensor sleeve 22 is secured, or affixed, internally to pack-off pipe 20 , with first end 32 of sensor sleeve 22 being open towards pipe first end 26 of downhole sensor assembly 10 . A glue-like substance or weld is preferably utilized to secure sensor sleeve 22 in pack-off pipe 20 . However, other means of securing sensor sleeve 22 may be utilized, as long as the securing of sensor sleeve 22 provides a water-tight seal within pack-off pipe 20 . Sensor 24 is preferably further sealed into pack-off pipe 20 by substantially filling annulus 54 with a fluid compound, such as a thermosetting polymer. Sensor 24 is secured in sleeve second end 38 of sensor sleeve 22 as described herein. Pipe second end 28 of pack-off pipe 20 is sealed by applying shrink wrap 56 to pack-off end 52 and pipe second end 28 .
[0025] The method of pressure testing sensor 24 for calibration prior to deployment in wellbore 18 includes attaching a piece of test equipment to sleeve first end 32 of sensor assembly 10 . The test equipment is threadedly secured in sleeve first end 32 of said sensor assembly 10 and forms test chamber 42 between the test equipment and sensor 24 . A known pressure is applied to test chamber 42 with the test equipment. A measurement of the pressure sensed by sensor 24 is taken.
[0026] The pressure measured by sensor 24 is compared to the known pressure from the test equipment. If the measured pressure is substantially similar to the known pressure, sensor 24 is acceptable. If the measured pressure is not substantially similar to the known pressure, sensor 24 has failed the test. The sensor 24 that failed may be retested, or another sensor assembly 10 may be used to replace the failed sensor 24 . Once the testing is completed, the calibrated pressure of sensor 24 is known and the test equipment is removed from sleeve first end 32 . If sensor 24 is acceptable, sensor assembly 10 is ready for deployment in wellbore 18 .
[0027] The assembled sensor assembly 10 is attached tubing string 12 as described herein. Sensor assembly 10 is inserted to wellbore 18 , along with tubing string 12 , to provide detection of a parameter within wellbore 18 .
[0028] Other embodiments of the current invention will be apparent to those skilled in the art from a consideration of this specification, or practice of the invention disclosed herein. Thus, the foregoing specification is considered merely exemplary of the current invention with the true scope thereof being defined by the following claims. | The present invention relates to a sensor assembly for downhole use in a wellbore. This invention also relates to a new pack-off assembly housing the sensor. The new pack-off assembly protects the sensor from the environment and from impact damage. Additionally, the new pack-off assembly allows for the testing of the sensor immediately prior to insertion into the wellbore. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to the field of golf clubs and in particular, to the driver or number 1 wood used for tee shots.
A persistent problem, which is worse for golfers of high handicaps, is failure to hit the golf ball fully on the club strike face. The hits are sometimes partly off and even entirely off the face, with consequent extremely bad effects on the distance and accuracy of the hit. There are practical limits to enlarging the club strike face to reduce this problem. This fault of having the ball partially off the club face at impact is much less common with low handicap golfers, but it does happen now and then. For them, a small improvement is relatively as important as a large improvement is for a high handicap golfer.
A study was undertaken to determine if the typical shape of the face was reasonably suited to the typical pattern of hits on the face. The impact of a driver on a golf ball flattens the ball and leaves a circular contact area about 0.7 inch diameter or greater, with a standard golf ball. The center of this circular contact area will be referred to as the center of impact. An analysis was made of 11 hits by each of 28 golfers, with a driver, a 5-iron, and a 9-iron. The club strike face was covered with marking tape which marked the impact area and the locations of the centers of each of the impacts was measured and recorded. The study showed that there was a pronounced elliptical distribution pattern of impacts over that many swings, and we call this pattern the "hit pattern". Further, it was found that for drivers this elliptical pattern was rotated upward at the toe about 32 degrees.
The study showed that the driver faces were not oriented to take advantage of the shape of the hit patterns and the present invention relates to tilting the long axis of the outline of the face upward at the toe of a driver to cause a better match with the hit pattern. Enlarging the face is also helpful as stated, but when the face is enlarged and also tilted appropriately, the improvement is much enhanced.
In most prior art, commercially available driver face shapes have only a small amount of upward tilt and none appears to have nearly the tilt angle which minimized the percentage of hits which were off of the face (or partly off the face).
In U.S. Pat. No. 3,625,518 a driver is disclosed as having a curved bottom surface and in the disclosure an elliptical representation of the hit area is shown. The minor axis of the hit area is recited as being parallel to the club shaft axis and the patent disclosure calls for a bulge on the face to be formed about an axis parallel to the minor axis of the hit area to compensate for off center impact. The face surface is also rolled about an axis parallel to the long axis of the ellipse. Thus while the elliptical ball strike region is known in the prior art the solution for using this information to adapt the club head tilt to aid golfers was not recognized.
U.S. Pat. No. 4,471,961 illustrates an axis of rotation in FIG. 17 but does not indicate that orienting the club face to be tilted upward toward the toe will aid in insuring the ball will be hit on the club face. This patent is also concerned with the bulge and roll of the driver face.
A prior club that had a circular face is known to have been sold in about 1990. Since it was circular it had no long axis and the idea of rotation of its long axis has no meaning. Its shape is much different from the approximate ratio of length to width of 2, which is a ratio appropriate to match the hit pattern and is widely preferred.
SUMMARY OF THE INVENTION
This invention relates to orienting a golf driver head (the strike face area of a golf driver) at an appropriate angle relative the horizontal (tilt angle) to reduce the frequency of occurrence of hits which are partly or entirely outside the perimeter of the face of the driver. Such erroneous hits cause very large errors in direction and distance and the present invention significantly reduces this problem by providing a better alignment between the pattern of hits and the orientation of the face.
A study of the location of the centers of impacts of a golf ball (called a "hit pattern") on the face of a golf club indicates that the hits fall into an elliptical pattern. For a driver, such ellipses have a long axis which is rotated 32 degrees upward at the toe of the club. The range of tilt angles that is reasonably effective is 20 to about 36 degrees and the best results are in the ranges of 28 to 34 degrees. The optimum is at or near 32 degrees. Where the long axis of the face, as defined later, is tilted to approximately match the 32 degree rotation of the hit pattern ellipse, the frequency of hits off the face is much reduced. The long axis of the face of current designs of drivers usually is tilted upward somewhat at the toe but much less than the optimum.
The present invention goes beyond face enlargement because there is substantial alignment of the long axis of the face with the long axis of the known elliptical pattern of hits on the face.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A through 1C are front elevational views of typical golf drivers showings typical driver face heights.
FIGS. 2A and 2B are front elevational views of prior art drivers which illustrate a popular traditional face shape and a more recent face shape, respectively.
FIG. 3 is a front elevational view of a prior art driver which exhibits an upward tilt of the face at the toe showing an upward limit of tilt commercially available.
FIG. 4 is a front view of a typical driver face showing a typical impact pattern of a ball on the face of a driver.
FIG. 5 is a graphical representation of the pattern or proportion of the scatter of impacts on the face of a driver for a particular individual golfer.
FIG. 6 is a front elevational view of a driver face oriented to embody the present invention,having effective upward tilt in direction of the toe.
FIG. 7 is an illustrative representation which defines some of the angles referred to in the text.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is best understood by a review of existing driver configurations as shown in FIGS. 1A, 1B, and 1C; 2A and 2B; and 3. A strike face shape which is elliptical is best, but the face shape is not of great importance so long as the face is roughly twice as long as it is wide. Non-elliptical face shapes are customary and customs are quite important in the game of golf, often for good reasons.
FIGS. 1A, 1B, 1C, 2A and 2B are very similar to FIGS. 41-1 and 41-2, page 387, in the book, "Golf Club Design, Fitting, Alteration, and Repair" by Ralph Maltby, copyright 1982. They show respectively, variations in driver face heights and in face shapes; for typical clubs. Numeral 4 in FIG. 1A represents a deep face, numeral 5 in FIG. 1B represents a conventional face depth, and numeral 6 in FIG. 1C represents a shallow face. FIGS. 2A and 2B illustrate a conventional driver face shape at 7 and a modern shape at 8.
FIG. 3 is another representative driver face, pertinent in that it has the largest upward tilt at the toe of commercially available prior art drivers which the present inventors were able to locate for analysis.
For hits without a tee, it is not practical to have the impact point as high on the club face as may happen for drivers, because that would require that the sole of the club dig deeply into the turf, spoiling the hit. Thus the present invention is not concerned with irons or fairway woods or other clubs than the driver. Even if irons do have the long axis tilted considerably upward at the toe,as most do, normal use of such clubs does not involve impacts centered high on the face as can and does happen for drivers, and so their upward tilt at the toe is of no significance.
FIG. 4 is a typical impact record, used for hit tests with 28 golfers. The marking tape which was applied to the driver face is represented at 10 and a typical ball impact mark is indicated at 12. The x and y position of the center of each ball impression was measured, x being the distance from the geometric center of the driver strike face toward the heel (negative if toward the toe), and y being the distance upward from the edge between the sole and the strike face of the club. For each golfer, the clubs used were the driver, the 5-iron, and the 9-iron for analysis. Only the data for the driver is of concern here. Various handicaps were represented for both men and women.
It was found that in both the x and y directions the distribution of the centers of the impacts was a "normal distribution" in statistical terms, or very nearly so.
This characteristic allows the distributions to be described as a family of ellipses, such as shown in FIG. 5 for a 15 handicap golfer. Size and proportions of these ellipses and these angular orientations were varied by computer methods until we found the best match with the data. FIG. 5 uses a modification in which we have projected the hit pattern onto a vertical plane which is perpendicular to the sole line, which is approximately a vertical plane through the bottom of the face.
It was found that low handicap golfers had smaller ellipses and high handicap golfers had larger ellipses. The average for these golfers was an ellipse rotated at 32 degrees (toe high) for drivers.
FIG. 5 shows the actual hit pattern ellipses, near actual size, for the case of handicap 15. The overall length L of the ellipse is 2.81 inches and width W is 1.22 inches for the case of handicap 15 and for the size of ellipse which contains 98.9% of the center of the impacts (the outer ellipse in FIG. 5). The inner ellipses of FIG. 5 show the progressively smaller sizes which contain the various percentages of impacts within such ellipse as indicated in the figure. In statistical terms, these percentages represent 3, 2, 1.35, 1, and 0.5 standard deviations for the lengths of semi-major and semi-minor axes of the ellipses.
The correlation of ellipse size with handicap was fairly good as might be expected. This allowed making a mathematical description of the ellipse for a driver in the form of equations.
These equations are as given below using a nominal loft angle of 11 degrees for a driver, and using the following definitions: a is the standard deviation in the direction of the long axis of the ellipse, b is the standard deviation in the direction of the short axis, A is the area of this ellipse, R is a/b=2.314, HCP is the handicap, HPA (Hit Pattern Angle) is the angle by which the axis of the ellipse is rotated from horizontal such as to raise the toe end. SQR(n) means the square root of n and * means to multiply. Lengths are in inches and angles are in degrees.
(1) A=0.1094+.01263*HCP
(2) R=2.314
(3) HPA=32.0
(4) a=0.8582*SQR(A)
(5) b=0.3709*SQR(A)
Thus, when a is taken to be the semi-major axis and b is the semi-minor axis, these equations describe ellipses which contain one standard deviation of the scatter in each direction. Joint probability density analysis shows that for one standard deviation, 39.3% of all points are within the ellipse. Similarly, ellipses twice as long and twice as wide will contain 2 standard deviations in each direction, which is 86.5% of the points and ellipses having 3 times these dimensions will contain 98.9%.
Accordingly, for example, where an ellipse contains 98.9% of the center points of the hits, its semi-major axis is 3*a which gives 6*a for its major axis or "long axis" or "overall length". Similarly its width is 6*b. The area of an ellipse is pi*c*d where pi=3.1416, c is the semi-major axis and d is the semi-minor axis. Thus for the 98.9% ellipse, each of its axes are three times longer than the ellipse containing 39.3% (or one standard deviation) of points so its area is 3 squared or 9 times greater. This example is illustrated in FIGS. 6 and 7 and the 98.9% ellipse is in FIG. 5.
There was no marked difference between men and women when the results are expressed as shown by the equations above. The HPA was less for clubs shorter than the driver and the size of the pattern was smaller. As expected, smaller handicaps have smaller patterns.
For easy examination, these results (a and b in inches) for a driver are given in tabular form as follows:
TABLE 1______________________________________SIZE OF HIT PATTERN ELLIPSEShandicap area a b______________________________________0 .109 .284 .12310 .236 .417 .18015 .298 .469 .20320 .362 .516 .22330 .488 .600 .259______________________________________
Off-center hits (which are still on the face) are detrimental because they alter the direction and distance of the hit as compared to center hits. This is well-known and widely studied. This type of error is different from the off-the-face errors with which this invention is concerned.
Especially for high handicap golfers, the hit is often so far from center that it is partly or even entirely off the hitting face of the club. This is a much smaller problem for fairly good golfers, but hits sometimes happen where the impact pattern is at least partly off the hitting face. Only the very best golfers almost always avoid this problem.
For these reasons, the size, shape, and orientation of the hitting face is very important. Good golfers are also concerned about these face design characteristics. The reason is that even though they generally make much smaller errors, a small error is relatively as important for good golfers as a very large error for a poor golfer.
The optimum face shape is therefore an ellipse with the same proportions as the hit pattern and oriented with its axis tilted upward at the toe end by 32 degrees, the same as for the hit pattern ellipses. Tilt angles of between 20 and 36 degrees are useful and a preferred range is between about 28 degrees and 34 degrees.
Furthermore, the face area should be as large as practical. Size is limited. If much larger than usual driver face size, the club head tends to weigh more than is acceptable and the result is that very large driver heads tend to be too fragile. Aerodynamic drag also increases for large faces, but experimental and theoretical studies show that this is generally a rather small influence.
FIG. 6 is representative of the face orientation of the present invention. The essential difference is that the long axis of the face is tilted up considerably more at the toe than the prior art. This is explained further below.
In FIG. 6, the ellipse size for a 15 handicap golfer which contains 98.9% of hits, was superimposed on the strike face image. This shows the benefits of tilting the long axis of the face outline to match the orientation of the ellipse. After this tilting, the face outline is a better match with the elliptical hit pattern.
In the above discussion, the "long axis" of a driver face is discussed, but for purposes of this specification it is defined in mathematical terms as the axis of the smaller of the two principal moments of inertia through the centroid of the surface representing the driver face. These terms also are further defined.
Again for purposes of this specification, the surface representing the driver face is defined as the projection of the actual curved driver face (which has bulge and roll) onto the plane surface which is tangent to the driver face at its center. This is much the same as the outline of the face as seen in the flat (plane) surface of a photo of the driver face. FIGS. 1-6 are representative of such projections.
A shape such as this has a "centroid", often called a center of gravity, which is the point at which a cardboard cut-out of the shape would balance on a pencil point.
Such a cut-out has a moment of inertia when rotated about any axis. In this analysis one is only concerned about axes through the centroid, and with two axes which are perpendicular to each other and which are both in the plane of the drawing figure. It is well known that there is one angular orientation of these axes at which there is a maximum moment of inertia about one axis and a minimum moment of inertia about the other. These are called the "principal axes". While illustrated and discussed in relation to a cardboard cut-out, actually the important meaning is for a plane area having no thickness and no weight. Mathematically, it is the integral of all incremental areas times the square of their perpendicular distances from the axis. A more correct but less used name is second moment, rather than moment of inertia.
For more detail on this subject, reference may be made to a text or handbook, such as pages 3-10 through 3-14 of "Standard Handbook for Mechanical Engineers", Baumeister and Marks, McGraw-Hill, copyright 1958.
FIG. 7 illustrates and precisely defines the angles discussed above. In FIG. 7, the solid line 71 is the horizontal. The dashed line 72 is the long axis of the hit pattern 75. The outline of the face is 76. The line 73 is the axis of the face which has minimum moment of inertia as explained and defined above. The shaft centerline is shown at 74.
HPA is the angular orientation of the long axis of the hit pattern ellipses. For drivers, HPA is 32 degrees. TLT is the angle by which the face axis 73 is rotated or "tilted".
At the golfer's address position, the shaft axis is at the LIE angle shown in FIG. 7. The LIE angle is generally considered to be 54 degrees for drivers, but there is no universal recognition of this number.
If a different value were chosen for LIE angle, the value for TLT would change. Therefore, we define FOA, the Face Orientation Angle, as shown in FIG. 7. FOA rather than TLT is thus the preferred description of the face orientation. This definition avoids any concern with the value for LIE angle, and as a result, there is no concern with angular orientations with respect to horizontal.
The orientation of the principal axis which represents the minimum moment of inertia of the driver face shapes of numerals 7 and 8 of FIGS. 2A and 2B and for FIG. 3 were measured. All were tilted upward somewhat at the toe. The tilt angle is labeled TLT in FIGS. 2A 2B and 3. The respective values for TLT were 8.0, 2.3, and 16.7 degrees.
For these 3 examples, it is of interest that the grooves in the face are generally not horizontal when the club is held at the normal position. For FIGS. 2A and 2B, horizontal was estimated as the tangent to the bottom edge of the face at the center of the face insert. For FIG. 3, the shaft was set at an angle of 54 degrees above horizontal, the design value. The respective groove angles were 3.1, 1.8, and 8.0 degrees, in all cases with the toe ends of the grooves high and heel ends low. It is important to note that TLT refers to the angle of the axis above the horizontal, not above the groove lines.
FIG. 6 shows a driver head 20 having a shaft 21, a face outline 23, and a superimposed ellipse 22 which is the outer 98.9% ellipse of FIG. 5. FIG. 6. incorporates an example of our improved TLT angle for the face outline 22, which is 23.2 degrees in this case. This design is a compromise between a larger TLT angle for even better performance and generally accepted appearance. A design for optimum performance would have used an elliptical face of the largest size consistent with adequate strength of the head, and the optimum value of 32 degrees TLT at the instant of impact. TLT angle at impact is about 1 to 4 degrees less than the value of TLT at address, because centrifugal force on the center of gravity of the head bends the shaft slightly downward during the swing, the amount depending on the square of the head speed and other factors.
A statistical analysis of the percentage of hits for which the impact pattern would be partly off the edge of the face was made for the design of FIG. 6. Consideration was made of the cases when the face long axis had values of TLT of 23.2, 13.2, and 3.2 degrees. The last, 3.2 degrees, is representative for conventional (prior art) TLT angle for this face shape. These results are given in Table 2. MPC approximately represents the minimum percentage of the impact area of the hit which is on the face. For example, MPC=80 means that a hit is counted as on the face if 80% or more of its impact area is within the boundary of the face.
TABLE 2______________________________________PERCENTAGE OF HITS OFF OF THE FACEHcp MPC TLT = 3.2 TLT = 13.2 TLT = 23.2______________________________________0 100 7.4 5.1 0.10 80 0.1 0.0 0.00 50 0.0 0.0 0.010 100 30.1 26.4 19.410 80 5.6 2.8 0.010 50 0.4 0.0 0.020 100 50.9 43.6 42.920 80 16.4 7.4 0.020 50 4.6 0.5 0.030 100 55.6 51.4 46.330 80 26.1 18.2 11.730 50 7.4 4.4 2.8______________________________________
Table 2 shows the marked advantage of a suitable TLT angle for higher handicap golfers. Also, as stated earlier, it is an important advantage, even though small, for good golfers.
In the research described above, what is fundamental is the relation between the face orientation and the shaft axis. In order to eliminate variables which are extraneous to the relation, the term "face orientation" angle is used in this description. FOA, as explained in connection with FIG. 7, is defined as the angle which lies in the plane of the shaft axis and the centroid of the face of the driver (a line and a point uniquely define a plane). Thus, FOA =TLT +LIE. The centroid has its exact mathematical meaning and its simplified name of center of gravity of the surface off the head, and the fact that the surface of the head is generally curved does not alter the meaning as compared to cases where the surface in question lies in a plane.
The analysis is done by projecting the outline of the face onto this plane. The principal moments of inertia of the closed curve thus obtained are determined. Finally, the FOA angle between the shaft and the axis of the lower of these two moments of inertia is found mathematically.
This definition is independent of the numerous other characteristics of a driver such as loft angle, lie angle, bulge, roll, etc.
Examination of cases shows that this process alters the shape and size of the face boundary only modestly.
Using this definition of face orientation, it was found that the face orientation angles of the prior art driver faces of FIG. 2A, numeral 7 to be 62.0 degrees, FIG. 2B, numeral 8 to be 56.3, and FIG. 3 to be 70.7 degrees. With this definition, the driver of FIG. 3 had the largest face orientation angle of any commercially available prior art which was found for analysis and the other two drivers are typical of prior art.
If a club face is elliptical and has a TLT angle of 32 degrees to match the HPA of 32 degrees, as shown in FIG. 5, and if the club has the usual LIE angle of 54 degrees, its face orientation angle, FOA, would be 86 degrees. Thus, the preferred range of values of FOA is between about 80 and 90 degrees. A face orientation angle of at least 74 degrees is preferred and it should not be more than about 90 degrees.
In Table 2, the tilt angles (TLT) of 3.2, 13.2 and 23.2 degrees correspond respectively to face orientation angles of 57.2, 67.2, and 77.2 degrees.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | A golf club, specifically a driver, has a roughly elliptical face shape oriented so that the long axis of the ellipse is tilted upward at the toe at an angle of 20 degrees or more. This causes better agreement between the hit pattern and the perimeter of the club face, with the important result of minimizing the percentage of impacts which are not completely on the face of the club. This arrangement is for drivers since no other clubs are normally used with a tee and a consequence is that tilting the ball strike region of the face is not helpful for such clubs. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of heat exchangers, especially for motor-vehicle engine cooling installations. It relates more particularly to heat exchangers with flexible tubes, produced from plastic, for example.
2. Description of Related Art
Such heat exchangers, described especially in the unpublished French patent Application No 98 04966 by the Applicant, includes tubes produced from a substance which is substantially flexible and the extremities of which communicate with at least one manifold for a heat-exchange fluid, interacting, for example, with an airflow which passes through the exchanger.
So as to increase the thermal interaction by the flow with the tubes of the exchanger, it is currently desirable to maintain interstices between the tubes, through which the airflow penetrates. Such interstices should furthermore make it possible to perturb the flow in the manner of the perturbing vanes which heat exchangers with rigid tubes usually include.
SUMMARY OF THE INVENTION
The present invention then improves on the situation.
It is concerned with a heat exchanger having flexible tubes, of the abovementioned type, which, according to one general characteristic of the invention, includes means for holding the tubes in substantially parallel rows. The tubes are shaped so as to exhibit general shapes of substantially sinusoidal lines. The sinusoids of two tubes in contact, of two respective consecutive rows, are substantially mutually offset, with respect to one another, such that the two tubes are held in two contact areas per period of sinusoids.
The sinusoids of the respective tubes of two consecutive rows are preferably substantially in phase opposition, while the sinusoids of the same row are in phase.
According to another optional characteristic of the present invention, the contact areas of the respective tubes of consecutive rows are substantially inscribed within a plane perpendicular to the rows.
Advantageously, the spacing between the rows is substantially constant.
According to another advantageous characteristic of the invention, at least a part of the outer surface of the tubes, comprising the abovementioned contact areas, is coated with a layer of adhesive in order to form means for holding the tubes.
In one preferred embodiment of the present invention, the outer surfaces of the tubes carry a material made adhesive by a vulcanizing treatment, thus forming the abovementioned layer of adhesive.
In one more elaborate embodiment of the invention, the holding means further include a plurality of rods substantially perpendicular to the rows and each installed between the respective sinusoids of consecutive rows, in order to hold the tubes of the consecutive rows spaced substantially apart.
BRIEF DESCRIPTION OF THE DRAWINGS
Other advantages and characteristics of the present invention will emerge on reading the detailed description below and the attached drawings, on which:
FIG. 1 diagrammatically represents a partial view of a device for cooling the engine of a motor vehicle in the example described,
FIG. 2 represents a diagrammatic view of a heat exchanger, in particular of a cooling radiator 2 of a device represented in FIG. 1,
FIG. 3A represents the tubes of a heat exchanger according to the present invention, shaped into lines of substantially sinusoidal shape,
FIG. 3B represents the tubes of FIG. 3A, in a front view,
FIG. 3C is a view along the section C—C of FIG. 3B, in the sectional plane of the tubes,
FIG. 3D is a view along the section D—D of FIG. 3B,
FIG. 3E is a side view of the tubes of FIG. 3A,
FIG. 4A represents the tubes of a heat exchanger, which are fitted with parallel rods,
FIG. 4B is a top view of the tubes of FIG. 4A, and
FIG. 4C is a side view of the tubes of FIG. 4 A.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The attached drawings in essence contain elements of a certain character. They could not only serve to give a better understanding of the present invention but also contribute to its definition, as the case may be.
FIG. 1 is first of all used as reference, in order to describe a device for cooling a motor-vehicle engine.
Such a device includes, in a way, which is itself known, a motor-driven fan unit 1 equipped with a plurality of blades. The motor-driven fan unit 1 is usually placed behind the vehicle grille (not represented). A heat exchanger according to the invention is interposed in an airflow (arrows F) which the rotation of the blades of the motor-driven fan unit 1 or else the movement of the vehicle itself produces. In practice, the heat exchanger is fed with the engine-cooling liquid, usually under the control of a thermostatic valve 3 . Arranging such a valve in the circuit of the cooling liquid 4 generally makes it possible to obtain satisfactory efficiency of the engine M when it is started from cold, by cutting off the supply to the radiator.
FIG. 2 is now used as reference in order to describe the structure of the heat exchanger 2 (cooling radiator, in the example). This heat exchanger includes flexible tubes 20 (represented by hatching in FIG. 2 ), which are generally produced from a plastic, which communicate via their extremities with two manifolds 21 and 22 . In fact the manifolds are fitted with apertures 215 and 225 tightly accommodating the extremities of the tubes 20 . In practice, the manifolds include collector plates equipped with apertures 215 and 225 and which thus form means for holding the tubes, in particular at their extremities.
The manifolds 21 and 22 usually feature compartments 210 , 211 , 212 and 221 , 222 , separated by partitions 213 , 214 and 223 , respectively, in order to define a path for the abovementioned heat-exchange fluid (cooling liquid in the example described), between an inlet C (arrow E) which communicates with an intake pipe 23 and an exit (arrow S) which communicates with a discharge pipe 24 . In the example represented in FIG. 2, the manifolds include five compartments in all, and the heat-exchange fluid performs three “outward” and two “return” journeys in all from the manifold 21 to the manifold 22 .
The paths for the fluid between the two manifolds 21 and 22 are then provided by the tubes 20 , in which the fluid circulates. Hence, the tubes interact thermally with the airflow F. However, in order to optimize the heat exchange between the tubes 20 , on the one hand, and the airflow F, on the other hand, it is necessary to keep the tubes spaced substantially apart from one another in order to create interstices between them.
FIGS. 3A to 3 E are used as reference then in order to describe the set of tubes of a heat exchanger according to a first embodiment of the present invention.
According to one general characteristic of the invention, the tubes 20 of the exchanger are arranged in rows 20 A, horizontal in the example described (FIG. 3 E). These rows are substantially parallel to each other and spaced, in the example described, by a distance corresponding substantially to one tube thickness 20 , such that the various rows are substantially adjacent in pairs of respective tubes of two consecutive rows, substantially in contact with one another.
By referring to FIG. 3A, it is apparent that the tubes overall exhibit generally substantially sinusoidal shapes. The tubes 211 , 212 of the same row 20 A have their sinusoid substantially in phase. Referring to FIG. 3B, it is apparent that two tubes 211 , 212 in contact, of two consecutive, respective rows, are in phase opposition and are in contact on areas 210 corresponding to nodes of two sinusoids.
FIG. 3C represents a sectional view (sectional plane of the tubes) of the nodes of the abovementioned sinusoids. The tubes of the same row 20 A are substantially spaced from each other, since the sinusoids of a single row are in phase, whereas the tubes of two consecutive rows are in contact in the region of the areas 210 (nodes of the sinusoids).
FIG. 3D is a sectional view (sectional plane of the tubes) of the troughs which the sinusoids of the tubes of the consecutive rows form. A separation then appears between two tubes of two respective consecutive rows, since the sinusoids of the two tubes are in phase opposition from one row 20 A to another, the rows being consecutive.
As FIG. 3C shows, the areas of contact 210 between the tubes of consecutive rows are inscribed within substantially horizontal planes, whereas the rows 20 A are arranged in substantially vertical planes. Hence, the areas of contact 210 of the respective tubes of consecutive rows are substantially inscribed within planes perpendicular to the rows 20 A.
The tubes are preferably produced from a plastic made adhesive by a heat treatment. Hence, after heat treatment, the tubes are joined mechanically to one another by bonding, in their contact areas 210 . In a variant, provision can be made to coat the outer surfaces of the tubes with a material exhibiting such a property, or even with a layer of adhesive so as to form the abovementioned holding means. In particular, spots of adhesive arranged on the contact areas 210 are sufficient to hold the tubes in rows 20 A and substantially fixed with respect to one another. It should be noted that the apertures of the manifolds are themselves arranged in rows and columns so as to keep the extremities of the tubes in rows from the outset.
FIGS. 4A to 4 C are now used as reference in order to describe the configuration of the tubes of a heat exchanger according to a second embodiment of the present invention.
As in the first embodiment described above, the tubes of a single row 20 A form sinusoids substantially in phase, whereas the tubes of two consecutive rows form sinusoids in phase opposition. In this embodiment, rods 213 , substantially parallel to each other and perpendicular to the rows 20 A are furthermore provided. Each of these rods is inserted into the troughs which the sinusoids of the tubes of consecutive rows form, as FIG. 4B shows. Such rods 213 thus make it possible to hold the tubes spaced substantially apart in the consecutive rows. Consequently, it is not necessary here to provide an adhesive coating on the tubes, in particular on the contact areas 210 . However, provision may further be made to give the outer surfaces of the tubes and, in particular, the outer surfaces of the rods, a layer of adhesive or a coating rendered adhesive by heat treatment, for example by vulcanizing, in order to reinforce the holding of the tubes in interleaved row [sic], as represented in FIGS. 3A and 4A.
Thus, the spacing between the tubes, in particular in the troughs of sinusoids, lets through the airflow F into the exchanger, while perturbing the flow F, advantageously. Moreover, the flexible tubes of the exchanger are, in general, of small diameter, typically about 1 to 4 mm and have a wall thickness close to 0.2 mm. It is then desirable to hold the tubes in a substantially rigid structure via their configuration in sinusoids described above, with a view to protecting them against the stresses of use (vibration, aging of the plastic, pressure of the heat-exchange fluid, etc.) which tends to make them fragile. Another advantage which the present invention confers then consists in that the tubes are held fixedly with respect to one another.
The period of the sinusoids preferably lies within a range of 40 to 80 mm and the amplitude, with respect to a general tube axis, lies between one tube half-diameter and two tube diameters. Referring especially to FIG. 3A, the extremities of the tubes are contiguous and flat over a length of about 5 to 25 mm, in order to be able to be connected to the manifolds, whereas the total length of the tubes is of the order of 500 mm, for example.
Clearly, the present invention is not limited to the embodiment described above by way of example. It extends to other variants.
Thus it will be understood that the sinusoids of the tubes of a single row are not necessarily in phase. In a variant, it may be envisaged, in fact, to arrange the tubes of a single row spaced sufficiently apart, whereas the phases between their sinusoid are substantially random.
Furthermore, the adjacent tubes of two consecutive rows are not necessarily in phase opposition. In fact it is sufficient to phase-shift the two sinusoids in order to allow an airflow to penetrate between the tubes. However, the configuration of two sinusoids in phase opposition allows maximum penetration by the air-flow through the troughs which they form.
In the example described above, the rows are substantially horizontal, whereas the contact areas 210 are arranged substantially in vertical planes. More generally, these planes are not necessarily perpendicular to the rows, in particular if the tubes which are adjacent between consecutive rows are offset laterally from one row to another.
The abovementioned means for holding the tubes (film of adhesive, coating rendered adhesive by heat treatment, spacer rods 213 ) are described above by way of example. Other holding means may be envisaged.
Furthermore, in the example represented in FIG. 2, the exchanger 2 includes two manifolds. In a variant, only one manifold may be provided, fitted with apertures into which the extremities of the tubes are inserted, while each tube exhibits a “U” shape, the two branches of which are made to undulate and are inscribed within the same row, or else interlaced, where each “U” branch is inscribed within a separate row.
Finally, the heat exchanger described above by way of example is intended to operate as a cooling radiator of a motor vehicle. In a variant, this heat exchanger may be designed as a heating radiator housed in a hot-air branch of a heating, ventilation and/or air conditioning installation for the passenger compartment of the vehicle, or else as an evaporator of an air-conditioning loop for this installation, or otherwise. Furthermore, the fluid passing through the heat exchanger (airflow F in the example described above) may be of a different type, for example oil, especially for an application of the heat exchanger as a radiator for cooling the engine oil. | A heat exchanger ( 2 ) with flexible tubes ( 20 ), particularly for a motor vehicle cooling installation. The tubes ( 20 ), for example made of a plastic material, are designed to carry a heat-exchanging fluid capable of co-operating with an air stream circulating through the exchanger ( 2 ). The inventive exchanger ( 2 ) comprises means for maintaining the tubes ( 20 ) in parallel rows. The tubes ( 20 ) are designed to be generally shaped like substantially sinusoidal lines. The sinusoids of two contacting tubes ( 211, 212 ) of two consecutive rows, are phase offset relatively to each other such that the two tubes ( 211, 212 ) are maintained in two contact zones ( 210 ) per sinusoid interval, thereby leaving interstices between the tubes ( 20 ) to enhance the penetration of the flux. | 5 |
FIELD OF THE INVENTION
[0001] This invention relates to triamide-substituted heterobicyclic compounds. These compounds are inhibitors of microsomal triglyceride transfer protein (MTP) and/or apolipoprotein B (Apo B) secretion and are useful for the treatment of obesity and related diseases. These compounds are also useful for the prevention and treatment of atherosclerosis and its clinical sequelae, for lowering serum lipids, and in the prevention and treatment of related diseases. The invention further relates to pharmaceutical compositions comprising these compounds and to methods of treating obesity, atherosclerosis, and related diseases and/or conditions with said compounds, either alone or in combination with other medicaments, including lipid lowering agents. Further still, the invention relates to certain processes and intermediates related thereto which are useful in the preparation of the compounds of the instant invention.
BACKGROUND OF THE INVENTION
[0002] Microsomal triglyceride transfer protein catalyzes the transport of triglyceride, cholesteryl ester, and phospholipids and has been implicated as a putative mediator in the assembly of Apo B-containing lipoproteins, biomolecules which contribute to the formation of atherosclerotic lesions. Specifically, the subcellular (lumen of the microsomal fraction) and tissue distribution (liver and intestine) of MTP have led to speculation that it plays a role in the assembly of plasma lipoproteins, as these are the sites of plasma lipoprotein assembly. The ability of MTP to catalyze the transport of triglyceride between membranes is consistent with this speculation, and suggests that MTP may catalyze the transport of triglyceride from its site of synthesis in the endoplasmic reticulum membrane to nascent lipoprotein particles within the lumen of the endoplasmic reticulum.
[0003] Accordingly, compounds which inhibit MTP and/or otherwise inhibit Apo B secretion are useful in the treatment of atherosclerosis and other conditions related thereto. Such compounds are also useful in the treatment of other diseases or conditions in which, by inhibiting MTP and/or Apo B secretion, serum cholesterol and triglyceride levels may be reduced. Such conditions may include, for example, hypercholesterolemia, hypertriglyceridemia, pancreatitis, and obesity; and hypercholesterolemia, hypertriglyceridemia, and hyperlipidemia associated with pancreatitis, obesity, and diabetes. For a detailed discussion, see for example, Wetterau et al., Science, 258, 999-1001, (1992), Wetterau et al., Biochem. Biophys. Acta., 875, 610-617 (1986), European patent application publication Nos. 0 584 446 A2, and 0 643 057 A1, the latter of which refers to certain compounds which have utility as inhibitors of MTP. Other examples of MTP inhibitors may be found in e.g., U.S. Pat. Nos. 5,712,279, 5,741,804, 5,968,950, 6,066,653, and 6,121,283; PCT International Patent Application publications WO 96/40640, WO 97/43257, WO 98/27979, WO 99/33800 and WO 00/05201; and European patent application publications EP 584446 and EP 643,057.
SUMMARY OF THE INVENTION
[0004] The present invention relates to compounds of the formula 1:
or a pharmaceutically acceptable salt thereof, wherein:
[0005] R 1 is substituted at the 5 or 6 position of formula 1 and has the structure:
[0006] m is an integer from 0 to 5;
[0007] n is an integer from 0 to 3;
[0008] p is an integer from 0 to 3;
[0009] L is —C(O)N(R 9 )—, i.e., L has the structure:
[0010] X is N or C(R c );
[0011] R 2 , R 8 , R 11 , R 12 , R 13 and R 16 are each independently selected from halo, cyano, nitro, azido, amino, hydroxy, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkoxy, methoxy, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, perfluoro(C 2 -C 4 )alkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkoxy, trifluoromethyl(C 1 -C 5 )alkoxy, (C 1 -C 6 )alkylthio, hydroxy(C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl(CR a R b ) q —, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 1 -C 6 )alkylamino-, (C 1 -C 6 )dialkylamino, amino(C 1 -C 6 )alkyl-, —(CR a R b ) q NR a R 14 , —C(O)NR a R 14 , —NR 14 C(O)R 15 , —NR 14 OR 15 , —CH═NOR 15 , —NR 14 C(O)OR 15 , —NR 14 S(O) j R 15 , —C(O)R 15 , —C(S)R 15 , —C(O)OR 15 , —OC(O)R 15 , —SO 2 NR a R 14 , —S(O) j R 15 , or —(CR a R b ) q S(O) j R 15 ;
[0012] each R a and R b is independently H or (C 1 -C 6 )alkyl;
[0013] R c is H or R 11 ;
[0014] each q is independently an integer from 0 to 6;
[0015] each j is independently 0, 1 or 2;
[0016] R 3 is H, halo, (C 1 -C 6 )alkyl, or mono-, di- or tri-halo(C 1 -C 6 )alkyl;
[0017] R 4 is H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 , —SO 2 R 15 or —(CR a R b ) q -phenyl, wherein the phenyl moiety is optionally substituted with from one to five independently selected R 16 ;
[0018] each r is independently an integer from 2 to 5;
[0019] each t is independently an integer from 1 to 6;
[0020] R 5 , R 6 and R 9 are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0021] R 7 is phenyl, pyridyl, phenyl-Z 1 - or pyridyl-Z 1 -, wherein the phenyl or pyridyl moiety is optionally substituted with one to five independently selected R 12 ;
[0022] Z 1 is —SO 2 — or —(CR a R b ) v —;
[0023] v is independently an integer from 1 to 6;
[0024] R 10 is phenyl, pyridyl, phenyl-Z 2 - or pyridyl-Z 2 -, wherein the phenyl or pyridyl moiety is optionally substituted with one to five independently selected R 13 ;
[0025] Z 2 is —S(O) j —, —O—, —(CR a R b ) w —, or —(O) k (CR a R b ) w (O) k (CR a R b ) q —;
[0026] w is independently an integer from 1 to 6;
[0027] each k is independently 0 or 1;
[0028] each R 14 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) t R 15 or —SO 2 R 15 ;
[0029] each R 15 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, wherein the alkyl, moieties of the foregoing R 15 groups are independently optionally substituted with 1 to 3 substituents independently selected from C 1 -C 6 alkyl, C 1 -C 6 alkoxy, amino, hydroxy, halo, cyano, nitro, trifluoromethyl and trifluoromethoxy;
[0030] and wherein any of the above “alkyl”, “alkenyl” or “alkynyl” moieties comprising a CH 3 (methyl), CH 2 (methylene), or CH (methine) group which is not substituted with halogen, SO or SO 2 , or attached to a N, O or S atom, optionally bears on said methyl, methylene or methine group a substituent selected from the group consisting of halo, —OR a , —SR a and —NR a R b .
[0031] In an embodiment of the invention, L is attached to the 2 position of R 1 and to the 5 position of formula 1, i.e., the compound of formula 1 has the structure of formula 1a:
[0032] In another embodiment of the invention, L is attached to the 2 position of R 1 and to the 5 position of formula 1, and R 10 is attached at the 3′ position.
[0033] In another embodiment of the invention, L is attached to the 3 position of R 1 and to the position formula 1. In another embodiment of the invention, L is attached to the 3 position of R 1 and to the 5 position of formula 1 and X is N. In still another embodiment of the invention, L is attached to the 3 position of R 1 and to the 5 position of formula 1, X is N and R 10 is attached at the 2 position of R 1 . In other embodiments of the invention, the attachment of L to R 1 is selected from the 3, 4, 6 or 6 position and the attachment of L to the compound of formula 1 is selected from the 5 position or 6 position.
[0034] In another embodiment of the invention, X is C(R c ).
[0035] In another embodiment of the invention, X is C(R c ), m is 0, n is 0, and p is 0 or 1.
[0036] In another embodiment of the invention, X is C(R c ), m is 0, n is 0, and p is 0 or 1, and R 10 is phenyl-Z 2 — attached at the 3 position of R 1 , wherein the phenyl moiety of R 10 is optionally substituted with one to five independently selected R 13 .
[0037] In another embodiment of the invention, X is C(R c ), m is 0, n is 0, and p is 0 or 1, and R 10 is phenyl attached at the 3 position of R 1 , wherein the phenyl moiety of R 10 is optionally substituted with one to five independently selected R 13 .
[0038] In another embodiment of the invention, R 7 is phenyl-Z 1 , wherein the phenyl moiety is optionally substituted with one to five independently selected R 12 . In a preferred embodiment of the invention, Z 1 is —(CR a R b ) v —, and in a more preferred embodiment, Z 1 is methylene, i.e., —CH 2 —.
[0039] In another embodiment of the invention, R 4 , R 5 , R 6 and R 9 are each independently selected from H, (C 1 -C 6 )alkyl, —(CR a R b ) q O(C 1 -C 6 alkyl) or —(CR a R b ) r R 15 .
[0040] In another embodiment of the invention, each R 12 is independently selected from halo, hydroxy, (C 1 -C 6 )alkyl, methoxy, (C 2 -C 6 )alkoxy, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkoxy, trifluoromethyl(C 1 -C 5 )alkoxy, (C 1 -C 6 )alkylthio and hydroxy(C 1 -C 6 )alkyl.
[0041] In another embodiment of the invention, each R 13 is independently selected from halo, hydroxy, amino, cyano, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, methoxy, (C 2 -C 6 )alkoxy, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkoxy, trifluoromethyl(C 1 -C 5 )alkoxy, (C 1 -C 6 )alkylthio, hydroxy(C 1 -C 6 )alkyl, —C(O)OR 15 and —NR 14 C(O)R 15 ; wherein R 14 is H or (C 1 -C 6 )alkyl; and wherein R 15 is H or (C 1 -C 6 )alkyl.
[0042] In another embodiment of the invention, R 10 is phenyl attached at the 3 position of R 1 , wherein the phenyl moiety of R 10 is optionally substituted with one R 13 . In a preferred embodiment, R 10 and R 1 both are phenyl, such that R 1 and R 10 together form a 1,1′-biphenyl group, wherein R 10 comprises the 1′-6′ positions of the biphenyl group and R 13 is substituted at the 4′ position of the biphenyl.
[0043] In another embodiment of the invention, R 4 is H, (C 1 -C 6 )alkyl or —(CR a R b ) q O(C 1 -C 6 alkyl).
[0044] In another embodiment of the invention, the carbon designated “a” in formula 1 is in the “(S)” configuration.
[0045] In a preferred embodiment of the invention, R 13 is trifluoromethyl.
[0046] In another preferred embodiment of the invention, R 3 is H, halo, or (C 1 -C 6 )alkyl.
[0047] In a more preferred embodiment of the invention, R 6 is methyl.
[0048] In a particularly preferred embodiment of the invention, the compound of formula 1 is (S)-1-ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl} amide.
[0049] In another particularly preferred embodiment of the invention, the compound of formula 1 is (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide.
[0050] In another more preferred embodiment of the invention R 3 is chloro.
[0051] In another particularly preferred embodiment of the invention, the compound of formula 1 is selected from the group consisting of:
3-chloro-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}amide; 3-chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}amide; 4′-trifluoromethyl-biphenyl-2-carboxylic acid [2-({[(benzyl-methyl-carbamoyl)-phenyl-methyl]-methyl-amino}-methyl)-3-chloro-1-methyl-1H-indol-5-yl]-amide, which is alternately named: 3-chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid {N-[2-(benzyl(methyl)amino)-2-oxo-1-phenylethyl]methyl}amide; 3-chloro-1-methyl-5-[methyl-(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}amide; and 3-chloro-1-ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}amide.
[0057] In another embodiment of the invention, X is C(R c ), m is 0, n is 0, and p is 0 or 1, and R 10 is phenyl-Z 2 - attached at the 3′-position, wherein the phenyl moiety of R 10 is optionally substituted with one to five independently selected R 13 and Z 2 is O or S.
[0058] In another embodiment of the invention, R 7 is phenyl-Z 1 , wherein the phenyl moiety is optionally substituted with one to five independently selected R 12 and Z 1 is O or S.
[0059] In another embodiment of the invention, R 7 is pyridyl-Z 1 , wherein the pyridyl moiety is optionally substituted with from one to five independently selected R 12 . In a preferred embodiment thereof, Z 1 is —(CH 2 )—.
[0060] In another embodiment of the invention, X is N and R 10 is phenyl optionally substituted with one to five independently selected R 13 .
[0061] In another embodiment of the invention, X is N and R 10 is phenyl optionally substituted with one to five independently selected R 13 , and R 7 is phenyl-Z 1 , wherein the phenyl moiety is optionally substituted with from one to five independently selected R 12 .
[0062] The present invention also relates to a compound of the formula 1b:
or a pharmaceutically acceptable salt thereof, wherein:
[0063] R 1 is substituted at the 5 or 6 position of formula 1b and has the structure:
[0064] or when R 7 is phenyl, pyridyl, phenyl-Z 1 - or pyridyl-Z 1 - optionally substituted with one to five independently selected R 12 , R 1 is (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, (C 5 -C 10 )bicycloalkyl, —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 , —SO 2 R 15 , (C 4 -C 10 )heterocyclyl, (C 5 -C 10 )heteroaryl, aryl or —(CR a R b ) q -aryl, wherein the cycloalkyl, heterocyclyl, heteroaryl or aryl moiety is optionally substituted with from one to five independently selected R 16 ;
[0065] m is an integer from 0 to 5;
[0066] n is an integer from 0 to 3;
[0067] p is an integer from 0 to 3;
[0068] L is —C(O)N(R 9 )—, as described above;
[0069] X 1 is N(R 4 ), S or O;
[0070] X 2 is N or C(R c );
[0071] R 2 , R 8 , R 11 , R 12 , R 13 and R 16 are each independently selected from halo, cyano, nitro, azido, amino, hydroxy, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkoxy, methoxy, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, perfluoro(C 2 -C 4 )alkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkoxy, trifluoromethyl(C 1 -C 5 )alkoxy, (C 1 -C 6 )alkylthio, hydroxy(C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl(CR a R b ) q —, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 1 -C 6 )alkylamino-, (C 1 -C 6 )dialkylamino, amino(C 1 -C 6 )alkyl-, —(CR a R b ) q NR a R 14 , —C(O)NR a R 14 , —NR 14 C(O)R 15 , —NR 14 R 15 , —CH═NOR 15 , —NR 14 C(O)OR 15 , —NR 14 S(O) j R 15 , —C(O)R 15 , —C(S)R 15 , —C(O)OR 15 , —OC(O)R 15 , —SO 2 NR a R 14 —S(O) j R 15 , or —(CR a R b ) q S(O) j R 15 ;
[0072] each R a and R b is independently H or (C 1 -C 6 )alkyl;
[0073] R c is H or R 11 ;
[0074] each q is independently an integer from 0 to 6;
[0075] each j is independently 0, 1 or 2;
[0076] R 3 is H, halo, (C 1 -C 6 )alkyl, or mono-, di- or tri-halo(C 1 -C 6 )alkyl;
[0077] R 4 is H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 , —SO 2 R 15 or —(CR a R b ) q -phenyl, wherein the phenyl moiety is optionally substituted with from one to five independently selected R 16 ;
[0078] each r is independently an integer from 2 to 5;
[0079] each t is independently an integer from 1 to 6;
[0080] R 5 and R 9 are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0081] R 6 is H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) q O(C 1 -C 6 alkyl), (CR a R b ) q S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0082] y is an integer from 0 to 5;
[0083] R 7 is (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, —(CR a R b ) q O(C 1 -C 6 alkyl), —(CR a R b ) q S(C 1 -C 6 alkyl); (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) r C(O)R 15 , —(CR a R b ) r C(S)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0084] or R 7 is phenyl, pyridyl, phenyl-Z 1 - or pyridyl-Z 1 - optionally substituted with one to five independently selected R 12 ;
[0085] or R 6 and R 7 taken together with the nitrogen atom to which they are attached together comprise (C 4 -C 10 )heterocyclyl, wherein the heterocyclyl moiety is monocyclic;
[0086] wherein the alkyl, cycloalkyl, and heterocyclyl moieties of the foregoing R 6 and R 7 groups are optionally substituted independently with 1 to 3 substituents independently selected from halo, cyano, nitro, trifluoromethyl, trifluoromethoxy, azido, —OR 15 , —C(O)R 15 , —C(O)OR 15 , —OC(O)R 15 , —NR 14 C(O)R 15 , C(O)NR a R 14 , —NR a R 14 , and —NR 14 OR 15 , C 1 -C 6 alkyl, C 2 -C 6 alkenyl, and C 2 -C 6 alkynyl; and
[0087] R 10 is phenyl, pyridyl, phenyl-Z 2 - or pyridyl-Z 2 -, wherein the phenyl or pyridyl moiety is optionally substituted with one to five independently selected R 13 ;
[0088] Z 2 is —S(O) j —, —O—, —(CR a R b ) w —, or —(O) k (CR a R b ) w (O) k (CR a R b ) q —;
[0089] w is independently an integer from 1 to 6;
[0090] each k is independently 0 or 1;
[0091] or R 10 is OR 17 , wherein R 17 is (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, perfluoro(C 2 -C 4 )alkyl, trifluoromethyl(C 1 -C 5 )alkyl, hydroxy(C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl(CR a R b ) q —, (C 2 -C 6 )alkenyl, or (C 2 -C 6 )alkynyl;
[0092] each R 14 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) t R 15 or —SO 2 R 15 ;
[0093] each R 15 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, wherein the alkyl, moieties of the foregoing R 15 groups are independently optionally substituted with 1 to 3 substituents independently selected from C 1 -C 6 alkyl, C 1 -C 6 alkoxy, amino, hydroxy, halo, cyano, nitro, trifluoromethyl and trifluoromethoxy;
[0094] and wherein any of the above “alkyl”, “alkenyl” or “alkynyl” moieties comprising a CH 3 (methyl), CH 2 (methylene), or CH (methine) group which is not substituted with halogen, SO or SO 2 , or attached to a N, O or S atom, optionally bears on said methyl, methylene or methine group a substituent selected from the group consisting of halo, —OR a , —SR a and —NR a R b .
[0095] In an embodiment of the invention, X 2 is C(R c ).
[0096] In another embodiment of the invention, X 2 is C(R c ) and L is attached to the 2 position of R 1 and to the 5 position of formula 1b.
[0097] In another embodiment of the invention, X 2 is C(R c ) and L is attached to the 2 position of R 1 and to the 5 position of formula 1b, R 10 is OR 17 and R 7 is phenyl-Z 1 , wherein the phenyl moiety is optionally substituted with one to five independently selected R 12 . In a preferred embodiment thereof, Z 1 is —(CR a R b ) t —.
[0098] In another embodiment of the invention, X 2 is C(R c ) and L is attached to the 2 position of R 1 and to the 5 position of formula 1b, and R 10 is phenyl attached at the 3 position of R 1 , wherein the phenyl moiety of R 10 is optionally substituted with one to five independently selected R 13 . In a preferred embodiment of the invention, R 6 in formula 1b is H or (C 1 -C 4 )alkyl.
[0099] In another preferred embodiment of the invention, the carbon designated “a” in formula 1b is in the (S) absolute configuration.
[0100] In another embodiment of the invention, R 13 in formula 1b is H or trifluoromethyl.
[0101] In another preferred embodiment of the invention, R 3 in formula 1b is H, halo, or (C 1 -C 6 )alkyl
[0102] In another preferred embodiment of the invention, R 7 in formula 1b is (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl or (C 2 -C 6 )alkynyl.
[0103] In a particularly preferred embodiment of the invention, the compound is selected from the group consisting of:
3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-oxo-1-phenyl-2-(prop-2-ynylamino)ethyl]amide; 3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-(isopropylamino-2-oxo-1-phenylethyl]amide; 3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-oxo-1-phenyl-2-(propylamino)ethyl]amide; 3-Chloro-1-methyl-5-[methyl-(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-(ethylamino)-2-oxo-1-phenylethyl]amide; 3-Chloro-1-methyl-5-[methyl-(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-(isopropylamino-2-oxo-1-phenylethyl]amide; 5-[(Biphenyl-2-carbonyl)-amino]-3-chloro-1-methyl-1H-indole-2-carboxylic acid [2-oxo-1-phenyl-2-(propylamino)ethyl]amide; and 5-[(Biphenyl-2-carbonyl)-amino]-3-chloro-1-methyl-1H-indole-2-carboxylic acid [2-(isopropylamino-2-oxo-1-phenylethyl]amide.
[0111] In an embodiment of the invention, R 6 and R 7 in formula 1b taken together with the nitrogen atom to which they are attached together comprise (C 4 -C 10 )heterocyclyl, wherein the heterocyclyl is optionally substituted independently with 1 or 2 substituents independently selected from (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, and (C 2 -C 6 )alkynyl and trifluoromethyl. In a preferred embodiment thereof, the heterocyclyl is selected from pyrrolidinyl, piperidinyl, morpholino and thiomorpholino. In a particularly preferred embodiment thereof, the heterocyclyl is pyrrolidinyl or morpholino.
[0112] The present invention also relates to compounds of the formula 2:
or a pharmaceutically acceptable salt thereof, wherein:
[0113] R 1 is substituted at the 5 or 6 position of formula 1 and has the structure:
[0114] m is an integer from 0 to 5;
[0115] n is an integer from 0 to 3;
[0116] p is an integer from 0 to 3;
[0117] L is —C(O)N(R 9 )—;
[0118] X is N or C(R c );
[0119] R 2 , R 8 , R 11 , R 12 and R 13 are each independently selected from halo, cyano, nitro, azido, amino, hydroxy, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkoxy, methoxy, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, perfluoro(C 2 -C 4 )alkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkoxy, trifluoromethyl(C 1 -C 5 )alkoxy, (C 1 -C 6 )alkylthio, hydroxy(C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl(CR a R b ) q —, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 1 -C 6 )alkylamino-, (C 1 -C 6 )dialkylamino, amino(C 1 -C 6 )alkyl-, —(CR a R b ) q NR a R 14 , —C(O)NR a R 14 , —NR 14 C(O)R 15 , —NR 14 OR 15 , —CH═NOR 15 , —NR 14 C(O)OR 15 , —NR 14 S(O) j R 15 , —C(O)R 15 , —C(S)R 15 , —C(O)OR 15 , —OC(O)R 15 , —SO 2 NR a R 14 , —S(O) j R 15 , or —(CR a R b ) q S(O) j R 15 ;
[0120] each R a and R b is independently H or (C 1 -C 6 )alkyl;
[0121] R c is H or R 11 ;
[0122] each q is independently an integer from 0 to 6;
[0123] each j is independently 0, 1 or 2;
[0124] R 3 is H, halo, (C 1 -C 6 )alkyl, or mono-, di- or tri-halo(C 1 -C 6 )alkyl;
[0125] each r is independently an integer from 2 to 5;
[0126] each t is independently an integer from 1 to 6;
[0127] R 5 and R 9 are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0128] R 6 is H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) q O(C 1 -C 6 alkyl), —(CR a R b ) q S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0129] y is an integer from 0 to 5;
[0130] R 7 is (C 1 -C 6 )alkyl, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, —(CR a R b ) q O(C 1 -C 6 alkyl), (CR a R b ) q S(C 1 -C 6 alkyl); (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) r C(O)R 15 , —(CR a R b ) r C(S)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0131] or R 7 is phenyl, pyridyl, phenyl-Z 1 - or pyridyl-Z 1 - optionally substituted with one to five independently selected R 12 ;
[0132] or R 6 and R 7 taken together with the nitrogen atom to which they are attached together comprise (C 4 -C 10 )heterocyclyl, wherein the heterocyclyl moiety is monocyclic;
[0133] wherein the alkyl, cycloalkyl, and heterocyclyl moieties of the foregoing R 6 and R 7 groups are optionally substituted independently with 1 to 3 substituents independently selected from halo, cyano, nitro, trifluoromethyl, trifluoromethoxy, azido, —OR 15 , —C(O)R 15 , —C(O)OR 15 , —OC(O)R 15 , —NR 14 C(O)R 15 , —C(O)NR a R 14 , NR a R 14 , and —NR 14 OR 15 , C 1 -C 6 alkyl, C 2 -C 6 alkenyl, and C 2 -C 6 alkynyl; and
[0134] R 10 is phenyl, pyridyl, phenyl-Z 2 - or pyridyl-Z 2 -, wherein the phenyl or pyridyl moiety is optionally substituted with one to five independently selected R 13 ;
[0135] Z 2 is —S(O) j —, —O—, —(CR a R b ) w —, or —(O) k (CR a R b ) w (O) k (CR a R b ) q —;
[0136] w is independently an integer from 1 to 6;
[0137] each k is independently 0 or 1;
[0138] or R 10 is OR 17 , wherein R 17 is (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, perfluoro(C 2 -C 4 )alkyl, trifluoromethyl(C 1 -C 5 )alkyl, hydroxy(C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl(CR a R b ) q —, (C 2 -C 6 )alkenyl, or (C 2 -C 6 )alkynyl;
[0139] each R 14 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) t R 15 or —SO 2 R 15 ;
[0140] each R 15 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, wherein the alkyl, moieties of the foregoing R 15 groups are independently optionally substituted with 1 to 3 substituents independently selected from C 1 -C 6 alkyl, C 1 -C 6 alkoxy, amino, hydroxy, halo, cyano, nitro, trifluoromethyl and trifluoromethoxy;
[0141] and wherein any of the above “alkyl”, “alkenyl” or “alkynyl” moieties comprising a CH 3 (methyl), CH 2 (methylene), or CH (methine) group which is not substituted with halogen, SO or SO 2 , or attached to a N, O or S atom, optionally bears on said methyl, methylene or methine group a substituent selected from the group consisting of halo, —OR a , —SR a and —NR a R b .
[0142] In an embodiment of the invention, X in formula 2 is C(R c ).
[0143] In another embodiment of the invention, L in formula 2 is attached to the 2 position of R 1 and to the 5 position of formula 2.
[0144] In another embodiment of the invention, wherein y is 1 or 2.
[0145] In another embodiment of the invention, R 10 in formula 2 is phenyl attached at the 3 position of R 1 , wherein the phenyl moiety of R 10 is optionally substituted with one to five independently selected R 13 .
[0146] In another embodiment of the invention, R 7 in formula 2 is phenyl-Z 1 , wherein the phenyl moiety is optionally substituted with one to five independently selected R 12 . In a preferred embodiment thereof, Z 1 is —(CR a R b ) t —.
[0147] In another embodiment of the invention, R 6 in formula 2 is H or (C 1 -C 4 )alkyl.
[0148] In another embodiment of the invention, the carbon designated “a” in formula 2 is in the (S) absolute configuration.
[0149] In a preferred embodiment of the invention, R 13 in formula 2 is trifluoromethyl.
[0150] In another preferred embodiment of the invention, R 3 in formula 2 is H, halo, or (C 1 -C 6 )alkyl.
[0151] The invention also relates to a process for preparing a compound of formula 1 which comprises forming an amide linkage between a compound of the formula AB1:
[0152] and a compound of the formula C:
wherein
[0153] m is an integer from 0 to 5; n is an integer from 0 to 3; p is an integer from 0 to 3;
[0154] the amido nitrogen atom of —C(O)N(R 9 )— above is bonded to the 5 or 6 position of the indole;
[0155] X is N or C(R c ), wherein R c is H or R 11 ;
[0156] R 2 , R 8 , R 11 , R 12 , R 13 and R 16 are each independently selected from halo, cyano, nitro, azido, amino, hydroxy, (C 1 -C 6 )alkyl, (C 2 -C 6 )alkoxy, methoxy, (C 1 -C 6 )alkoxy(C 1 -C 6 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkyl, perfluoro(C 2 -C 4 )alkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, mono-, di- or tri-halo(C 2 -C 6 )alkoxy, trifluoromethyl(C 1 -C 5 )alkoxy, (C 1 -C 6 )alkylthio, hydroxy(C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl(CR a R b ) q —, (C 2 -C 6 )alkenyl, (C 2 -C 6 )alkynyl, (C 1 -C 6 )alkylamino-, (C 1 -C 6 )dialkylamino, amino(C 1 -C 6 )alkyl-, —(CR a R b ) q NR a R 14 , —C(O)NR a R 14 , —NR 14 C(O)R 15 , —NR 14 OR 15 , —CH═NOR 15 , —NR 14 C(O)OR 15 , —NR 14 S(O) j R 15 , —C(O)R 15 , —C(S)R 15 , —C(O)OR 15 , —OC(O)R 5 , —SO 2 NR a R 14 , —S(O) j R 15 , or —(CR a R b ) q S(O) j R 15 ;
[0157] each R a and R b is independently H or (C 1 -C 6 )alkyl;
[0158] each q is independently an integer from 0 to 6; each j is independently 0, 1 or 2;
[0159] R 3 is H, halo, (C 1 -C 6 )alkyl, or mono-, di- or tri-halo(C 1 -C 6 )alkyl;
[0160] R 4 is H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 , —SO 2 R 15 or —(CR a R b ) q -phenyl, wherein the phenyl moiety is optionally substituted with from one to five independently selected R 16 ;
[0161] each r is independently an integer from 2 to 5; each t is independently an integer from 1 to 6;
[0162] R 5 , R 6 and R 9 are each independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) r R 15 or —SO 2 R 15 ;
[0163] R 7 is phenyl, pyridyl, phenyl-Z 1 - or pyridyl-Z 1 -, wherein the phenyl or pyridyl moiety is optionally substituted with one to five independently selected R 12 ;
[0164] Z 1 is —SO 2 — or —(CR a R b ) v —;
[0165] v is independently an integer from 1 to 6;
[0166] R 10 is phenyl, pyridyl, phenyl-Z 2 - or pyridyl-Z 2 -, wherein the phenyl or pyridyl moiety is optionally substituted with one to five independently selected R 13 ;
[0167] Z 2 is —S(O) j —, —O—, —(CR a R b ) w —, or —(O) k (CR a R b ) w (O) k (CR a R b ) q —;
[0168] w is independently an integer from 1 to 6;
[0169] each k is independently 0 or 1;
[0170] each R 14 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, —C(O)R 15 , —C(S)R 15 , —(CR a R b ) t O(C 1 -C 6 alkyl), —(CR a R b ) t S(C 1 -C 6 alkyl), —(CR a R b ) r C(O)R 15 , —(CR a R b ) t R 15 or —SO 2 R 15 ;
[0171] each R 15 is independently H, (C 1 -C 6 )alkyl, (C 3 -C 8 )cycloalkyl, trifluoromethyl, trifluoromethyl(C 1 -C 5 )alkyl, wherein the alkyl, moieties of the foregoing R 15 groups are independently optionally substituted with 1 to 3 substituents independently selected from C 1 -C 6 alkyl, C 1 -C 6 alkoxy, amino, hydroxy, halo, cyano, nitro, trifluoromethyl and trifluoromethoxy;
[0172] and wherein any of the above “alkyl”, “alkenyl” or “alkynyl” moieties comprising a CH 3 (methyl), CH 2 (methylene), or CH (methine) group which is not substituted with halogen, SO or SO 2 , or attached to a N, O or S atom, optionally bears on said methyl, methylene or methine group a substituent selected from the group consisting of halo, —OR a , —SR a and —NR a R b ;
[0173] and L c is selected from a (i) a carboxylic acid or salt thereof (ii) an activated form of the carboxylic acid or (iii) an aldehyde.
[0174] In an embodiment, the carboxylic acid is optionally activated in-situ, using methods well known in the art. The above process is referred to herein as “Process I.” Process I is applicable to, and provides, a process for preparing each of the embodiments, preferred embodiments, more preferred embodiments and particularly preferred embodiments of the compound of formula 1, a detailed repetition of which is avoided for brevity. Methods for forming amide linkages are well-known in the art, some examples of which are provided herein.
[0175] In an embodiment, the employed form of the amine C may optionally be a salt with any acid that is compatible with the subsequent process options, and may additionally or optionally be a solution in a similarly compatible solvent or mixture of solvents.
[0176] In an embodiment, the employed forms of the carboxylic acid (or salt thereof) AB1 and amine C (or salt thereof) optionally include solvates and hydrates.
[0177] In an embodiment of Process I, the amide linkage between AB1 and C is formed by combining AB1, C, and PyBroP (about 1 eq) in a suitable non-aqueous solvent, followed by the addition of diisopropylethylamine (2-3 eq). In a preferred embodiment, the suitable solvent is methylene chloride or DMF. In a more preferred embodiment of Process I, the solvent is methylene chloride. In another preferred embodiment, Process I further comprises stirring or agitating the resulting mixture at room temperature for a period of from about 30 minutes to about 24 hours. In another preferred embodiment thereof, of Process I further comprises removal of the solvent and the purification of the product by TLC or flash chromatography using ethyl acetate/hexane as the eluting solvent.
[0178] In another embodiment of Process I, the amide linkage between AB1, wherein L c is an aldehyde, preferably C(O)H, and C is formed by a process (herein, the “Aldehyde Process”) which comprises (a) reacting the AB1 aldehyde with C in the presence of an acid, preferably acetic acid, in a suitable solvent, preferably methylene chloride, followed by (b) addition of NaB(OAc) 3 H and chloroform. In an preferred embodiment of the Aldehyde Process, the compound of formula 1 is purified from the organic layer, preferably by flash chromatography using methanol/chloroform. In a further embodiment of the Aldehyde Process, the AB1 aldehyde is formed by (i) combining a compound of formula AB1, wherein L c is a carboxylic acid, preferably —COOH, with N,O-dimethyl hydroxylamine hydrochloride salt and PyBroP in a suitable solvent; followed by (ii) addition of diisopropylethylamine and (iii) treatment of the resulting N,O-dimethyl hydroxyamide with DIBAL in a suitable solvent, to yield the corresponding aldehyde. In a preferred embodiment of the Aldehyde Process, the suitable solvent in step (i) is methylene chloride. In another preferred embodiment of the Aldehyde Process, the suitable solvent in step (iii) is THF.
[0179] In a preferred embodiment of Process I, referred to herein as “Process IC” for its use of carbodiimide, the amide linkage between AB1 and C, wherein L c is a carboxylic acid, is formed by (a) combining AB1 with a carbodiimide and a catalyst, e.g., 1-hydroxybenzotriazole hydrate (“HOBt”), in a suitable non-aqueous solvent, and (b) adding triethylamine and C to the mixture of step (a). In a more preferred embodiment of Process IC, the carbodiimide is EDC, i.e., 1-[3-(dimethylamino)propyl]-3-ethylcarbodimide hydrochloride, and even more preferably, the solvent is methylene chloride. In another embodiment, Process IC further comprises at least a second addition of triethylamine. In another embodiment, Process IC further comprises at least a second addition of triethylamine, optionally with further addition of the carbodiimide. In another embodiment of Process IC, a salt of the acid AB1 is used in step (a). Preferably, the salt is a sodium salt, i.e., L c is —C(O)O − Na + , and more preferably, the salt is a potassium salt, i.e., L c is —C(O)O − K +, and particularly preferably, the salt is a potassium salt, i.e., L c is —C(O)O − K + , crystallizing as the 2.5 mole hydrate. In a still further embodiment thereof, the acid salt AB1 is first treated with aqueous acid before combination with the other components in step (a); in this embodiment, the treatment with aqueous acid resulting in precipitation of the free acid as a solid, which is collected for use in step (a). In a preferred embodiment of the acid treatment step, the acid salt AB1 is treated with aqueous acid adjusted to a pH of from about 3 to about 4, with heating. In a more preferred embodiment, the acid salt is treated with an inert mineral acid, most preferably concentrated aqueous hydrochloric acid, or alternatively, an inert organic acid, preferably anhydrous and most preferably methanesulfonic acid, before step (a). In a still further embodiment, the compound of formula 1 is purified by (a) washing in saturated aqueous sodium hydrogen carbonate, (b) washing in aqueous acid, preferably, hydrochloric acid, and (c) washing with water, to provide purified compound of formula 1 in the non-aqueous solvent. In a still further embodiment, the non-aqueous solvent is replaced with amyl acetate, amyl alcohol, mixtures of methanol or acetonitrile with diisopropyl ether, or preferably mixtures of propan-2-ol and tert-butyl methyl ether, by distillation, and the solution is cooled in order to precipitate solid forms, e.g., polymorphs, of the compound of formula 1. Preferably, the solution of compound of formula 1 in mixtures of propan-2-ol and tert-butyl methyl ether is seeded with the desired solid form to facilitate precipitation of the desired solid form.
[0180] In another embodiment of the above process, the amide linkage between AB1 and C is formed by (a) reaction of the acid the 1,1′-carbonyldiiimidazole to produce its acyl imidazolide, i.e., yielding e.g., L c =—C(O)(1-C 3 H 3 N 2 ), and (b) reacting the imidazolide of AB1 with C, preferably in the presence of a suitable base. In this embodiment, some racemization of chiral center “a” in (S)-phenylglycine derivatives has been observed, thus, where preservation of stereochemistry is desirable, the use of the imidazolide reaction is less preferred than other embodiments described above. Preferred processes of the invention preserve the stereochemistry of the phenylglycine group.
[0181] In a preferred embodiment of each of the embodiments of Process I and Process IC, R 5 is hydrogen, R 6 is hydrogen, R 7 is benzyl, m, n and p are all 0, and the carbon designated “a” in formula C is in the (S) configuration. In another preferred embodiment of Process I, the amide linkage between AB1 and C is formed as in Example 45, step (g).
[0182] In a preferred embodiment of Process IC, R 4 is methyl, R 5 is hydrogen, R 6 is methyl, R 7 is benzyl, m is 0 and the carbon designated “a” in formula C is in the (S) configuration and the amide linkage between AB1 and C is formed as in Example 44, step (f).
[0183] Additional embodiments of methods for forming the amide linkages of the processes of this invention are described in the Examples, and it is to be understood that each of the embodiments exemplified as described below are intended to be included within the scope of the processes of this invention.
[0184] In a further embodiment of the above process, the compound of formula AB1 is prepared by a process which comprises forming an amide linkage between a compound of the formula A:
[0185] and a compound of the formula B1:
[0186] wherein L c is a carboxylic acid and L e is a carboxylic acid (C 1 -C 6 )alkyl ester, and R 2 -R 11 are as defined above.
[0187] In an embodiment, the amide linkage between A and B1 is formed by a process comprising (a) combining A and B1 with a suitable base, e.g. DIEA, a carbodiimide, e.g., EDC.HCl, and a catalyst, e.g. HOBT, in an organic solvent, e.g. DMF, followed by (b) distillation of volatile components, (c) partition between organic solvent and dilute aqueous acid, (d) replacement by distillation of the solvent with a non-solvent, e.g. tert-butyl methyl ether, diisopropyl ether or propan-1-ol, and (e) isolation of the product AB1-e by filtration.
[0188] In another embodiment, the amide linkage between A and B1 is formed by a process comprising (a) combining A with a chlorinating agent, e.g. oxalyl chloride or preferably thionyl chloride, in a compatible solvent e.g. toluene, acetonitrile, or 1,2-dichloroethane, in the presence of a catalyst to prepare the acid chloride, i.e. A wherein L c =—C(O)Cl, (b) optionally removing the excess reagent by distillation, (c) combining the acid chloride with B1 in the presence of a suitable base, e.g. DIEA, in compatible solvents, e.g. DCE, Toluene, EtOAc, acetonitrile, and mixtures thereof, followed by (d) isolation of product AB1-e as described in the preceding embodiment, or preferably by filtration of crude product from the reaction mixture, and reslurry of the crude in suitable non-solvents, preferably in mixtures of aqueous propan-2-ol, before refiltration.
[0189] A preferred feature of the above embodiment is the use of catalysis in the preparation of the acid chloride, i.e. A wherein L c =—C(O)Cl, to prevent the formation of the corresponding symmetrical carboxylic anhydride. Preferred catalysts are tertiary amides, e.g. DMF and DMAC, or pyridines, e.g. pyridine or DMAP or mixtures thereof. More preferred catalysts are tertiarybenzamides, e.g. N,N-dimethylbenzamide. Even more preferred catalysts are N-alkyl lactams, e.g. N-methylpyrrolidinone. Catalysis by iron salts and by tetraalkylureas, e.g. tetramethylurea, is known in the art.
[0190] The invention also relates to a compound of the formula AB1
wherein R 3 is H, halo or (C 1 -C 6 )alkyl, R 4 and R 9 are each independently H or (C 1 -C 6 )alkyl; m, n, and p are all 0, R 10 is phenyl optionally substituted with from one to five R 13 groups and L c is a carboxylic acid or salt thereof. In a preferred embodiment, L c is COOH. In another preferred embodiment, L c is a salt of the carboxylic acid, preferrably L c is the sodium salt of the carboxylic acid, i.e., —COO − Na + , more preferably L c is the potassium salt of the carboxylic acid, i.e., —COO − K + , and particularly preferably L c is the potassium salt of the carboxylic acid, i.e., —COO − K + , crystallizing as a 2.5 mole hydrate. In a preferred embodiment of the compound of formula AB1, R 3 is H or halo, R 4 is methyl, ethyl or propyl; m, n and p are both 0, and R 10 is phenyl optionally substituted with one or two R 13 groups. In a more preferred embodiment thereof, R 3 is H and R 4 is methyl. In another more preferred embodiment thereof, R 3 is H, R 4 is methyl and R 10 is phenyl optionally substituted with one R 13 group. In a particularly preferred embodiment, R 3 is H, R 4 is methyl and R 10 is phenyl substituted with one trifluoromethyl group. In a particularly preferred embodiment thereof, the trifluoromethyl group is in the 4′ position of the biphenyl group formed between R 10 and the phenyl to which it is attached.
[0191] The invention also relates to a compound of the formula AB1-e, wherein R 2 -R 11 are as defined above for the compound AB1, and L e is a carboxylic acid ester. In an embodiment, the ester is an alkyl ester, preferably a (C 1 -C 6 ) alkyl ester or a substituted-alkyl variation thereon. In a preferred embodiment, L e is the ethyl carboxylic acid ester, i.e., —C(O)OCH 2 CH 3 . In another preferred embodiment, L e is the methyl carboxylic acid ester, i.e., —C(O)OCH 3 .
[0192] The invention also relates to process for preparing a compound of formula C
or a stereoisomer thereof, which comprises reacting an amine of the formula HNR 6 R 7 with a compound of the formula
wherein R p is H or a protecting group.
[0193] In an embodiment, the protecting group is tert-butyloxycarbonyl (“BOC”). In another embodiment, the process comprises combining C′ with a catalyst, e.g. HOBt, and a carbodiimide in a suitable solvent, and adding the amine HNR 6 R 7 . In a preferred embodiment, the carbodiimide is N,N′-dicyclohexylcarbodiimide. In another preferred embodiment, the carbodiimide is EDC. In another preferred embodiment, the suitable solvent is dichloromethane. In a preferred embodiment, the mixture of C′, the amine HNR 6 R 7 , HOBt and carbodiimide is stirred for about 30 minutes to 24 hours before further processing. In an embodiment, the further processing comprises an aqueous work-up to provide the compound of formula C. In a preferred embodiment, the amine HNR 6 R 7 is N-methylbenzylamine, i.e., R 6 is methyl and R 7 is benzyl. In another preferred embodiment, R p is BOC and the amine is N-methylbenzylamine, and in a more preferred embodiment thereof, the resulting compound of formula C, (tert-butyl (RS)-2-[benzyl(methyl)amino]-2-oxo-1-phenylethylcarbamate), is treated with trifluorocaetic acid and triethylsilane in dichloromethane, followed by aqueous workup to yield (RS)-N-benzyl-N-methyl-2-phenylglycinamide. In a particularly preferred embodiment, R p is BOC and the amine is N-methylbenzylamine, and in a more preferred embodiment thereof, the resulting optically enriched compound of formula C, (tert-butyl (S)-2-[benzyl(methyl)amino]-2-oxo-1-phenylethylcarbamate), is treated with concentrated hydrochloric acid in propan-2-ol, followed by advantageous precipitation of (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride monohydrate from mixtures of propan-2-ol and tert-butyl methyl ether, resulting in a useful increase in the degree of optical enrichment.
[0194] A salt of the phenylglycine amide may be prepared, e.g., by treating the amide, e.g., (RS)-N-benzyl-N-methyl-2-phenylglycinamide, with di(o-toluoyl)-L-tartaric acid in a suitable solvent, e.g. ethyl acetate, to provide the di(o-toluoyl)-L-tartrate) salt, e.g. (RS)-n-benzyl-N-methyl-2-phenylglycinamide. Tartrate salts of the phenylglycine amides may be broken to provide the amide, which may be purified as its hydrochloride salt.
[0195] In another embodiment, racemic compounds of the formula C may be resolved via the selective precipitation of one of the enatiomers as its salt with an optically enriched chiral acid, of which many examples are known in the art, from suitable solvents, e.g. methanol and ethanol. Such optically enriched chiral acids may be naturally occuring or synthetic. The precipitated salts may be hydrates or solvates.
[0196] In a preferred embodiment, (RS)-N-benzyl-N-methyl-2-phenylglycinamide is treated with di(o-toluoyl)-L-tartaric acid in methanol at 20° C. The precipitated salt is filtered and washed with methanol, then dried providing (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate with 92.7% d.e. (chiral HPLC). This material is reslurried in hot methanol, filtered, washed and dried to providing (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate with 99% d.e. (37% overall yield).
[0197] The diastereomericly enriched salts formed as described in the previous embodiments may be broken to provide optically enriched free amines C, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide, which may be advantageously purified by crystallization as-is or by the formation of a salt with an achiral acid in the presence of suitable solvents, e.g. precipitation of (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride from mixtures of propan-2-ol and tert-butyl methyl ether.
[0198] In another embodiment, a racemic compound of the formula C may be resolved via the selective recrystallization of its salt with an optically enriched chiral acid, e.g. (RS)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate prepared as described above, from a suitable solvent, to provide diastereomericly enriched salts, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate. Breakage of these salts delivers optically enriched free amines of the formula C, which may be advantageously isolated and used as the hydrochloride salt, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride.
[0199] In another embodiment, where optically enriched compunds C are preferred, the unwanted enantiomer of the compound C may be recycled by racemization. In a more preferable embodiment, the racemization is applied to mother liquors from the resolutions described above by refluxing in the presence of a catalytic amount of a carbonyl compound, e.g. 2-chlorobenzaldehyde, thus allowing the isolation of second crops of diastereomerically enriched salts containing the desired enatiomer of compound C, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate with 92% d.e. in approximately 50% yield of the solute in the initial ethanolic mother liquors. In a still more preferred embodiment, the catalysed racemization is performed at a suitable temperature and concentration in-situ during the resoluton in a suitable solvent, prior to the isolation of the first crop of product; this “dynamic resolution” allows a first crop yield of product to be significantly greater than the 50% available by traditional salt resolutions. Dynamic resoultions are known in the art, but are considered far from trivial and highly substrate dependant.
[0200] In still another embodiment of a process for preparing an opticaly enriched compound of formula C, a homochiral amino acid, e.g. (S)-L-2-phenylglycine, is converted to the corresponding N-carboxyanhydride, e.g. (S)-4-phenyl-1,3-oxazolidine-2,5-dione, using methods well known in the art, which, may then be combined an amine, e.g. N-methylbenzylamine. The resulting mixture is then subjected to an aqueous work-up, providing the optically enriched aminoamide, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide, which may be purified as-is or as a suitable salt.
[0201] The invention also relates to a process for preparing a compound of formula 2 which comprises: (a) forming an amide linkage between a compound of the formula A and a compound of the formula B2:
[0202] and (b) forming an amide linkage between the product of step (a) and a compound of the formula C; wherein R 2 , R 3 , R 9 , L c , y and A and C are as defined above.
[0203] The invention also relates to a process for preparing a compound of formula 2 which comprises forming an amide linkage between a compound of the formula AB2
and a compound of the formula C; wherein R 2 , R 3 , R 9 , R 10 , R 11 and y are as defined above.
[0204] The invention also relates to a process for preparing a compound of formula 1b, wherein X 1 is S or O, which comprises: (a) forming an amide linkage between a compound of
the formula AB3:
and a compound of the formula C, wherein X 1 is S or O, and (b) forming an amide linkage between the product of step (a) and a compound of the formula C, wherein the compound of formula A and the compound of formula C are as defined above.
[0205] The invention also relates to a process for preparing a compound of formula 1b, wherein X 1 is S or O, which comprises: (a) forming an amide linkage between a compound of the formula B3 and a compound of the formula C; and (b) forming an amide linkage between the product of step (a) and a compound of the formula A, wherein A, B3 and C are as defined above.
[0206] It is to be understood that the methods of preparing the compounds disclosed herein, including the compounds of formulas 1, 1b and 2, their varied embodiments and synthetic precursors or intermediates are not limiting but only illustrative.
[0207] The compounds of this invention are useful as MTP/ApoB inhibitors.
[0208] The terms “compound(s) of formula 1”, “compound(s) of formula 1 b”, “compound(s) of formula 2”, etc. include a compound of formula 1 (or 1b or 2, respectively) as defined herein and all of the embodiments, preferred embodiments, more preferred embodiments, and particularly preferred embodiments of such compounds, including the compounds named or exemplified herein, each of which is a particularly preferred embodiment of the compounds defined by the formulas. Reference to “a compound of the invention” is meant to encompass any of the compounds of formula 1, formula 1b or formula 2 as those terms are defined above. Accordingly, reference to “a compound of the invention” in connection with any of the embodiments, preferred embodiments, more preferred embodiments or particularly preferred embodiments of the compositions, processes and methods of the invention described herein, as well as embodiments relating to salts, polymorphs, solvates, hydrates, prodrugs and isotopically-labelled derivatives of the compounds of the invention, is intended to refer to any of the compounds of formula 1 (or 1b or 2 respectively) as defined above, i.e., to any of the embodiments, preferred embodiments, more preferred embodiments or particularly preferred embodiments of the compounds, especially the compounds named or exemplified herein.
[0209] This invention also relates to the salts, polymorphs, solvates and hydrates of the compounds of the invention, as well as to the salts, polymorphs, solvates and hydrates of the synthetic precursors of each of the compounds of the invention. The invention relates to polymorphs of the compound of formula 1, wherein R 1 -R 8 are as defined above, having an X-ray powder diffraction patterns substantially the same as shown in any of FIGS. 1, 3 , 4 , and 5 . It is to be understood that some level of noise is inherent in the generation of a diffraction pattern, i.e., peaks in intensity are to be discriminated from background according to methods well-known in the art. In a preferred embodiment, the compound is (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide and the X-ray powder diffraction pattern is substantially the same as that shown in FIG. 1 . In a more preferred embodiment, the compound has an X-ray powder diffraction pattern having peaks at 2-theta values substantially the same as the 2-theta values for at least ten of the peaks of highest intensity in the X-ray powder diffraction pattern shown in FIG. 1 .
[0210] In an embodiment, the compound of the invention is a polymorph of the compound of formula 1 having a differential scanning calorimetry (DSC) profile substantially the same as that shown in FIG. 2 . In a preferred embodiment, the compound is (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide. In a more preferred embodiment, the compound exhibits a heat absorption onset temperature, peak temperature and characteristic shape substantially the same as that shown in FIG. 2 .
[0211] The term “pharmaceutically acceptable salt(s)”, as used herein, unless otherwise indicated, includes salts of acidic or basic groups that may be present in the compounds of the invention. For example, pharmaceutically acceptable salts include sodium, calcium and potassium salts of carboxylic acid groups and hydrochloride salts of amino groups. Other pharmaceutically acceptable salts of amino groups are hydrobromide, sulfate, hydrogen sulfate, phosphate, hydrogen phosphate, dihydrogen phosphate, acetate, succinate, citrate, tartrate, lactate, mandelate, methanesulfonate (mesylate) and p-toluenesulfonate (tosylate) salts. The preparation of such salts is described below.
[0212] The compounds of the invention that are basic in nature are capable of forming a wide variety of salts with various inorganic and organic acids. The acids that may be used to prepare pharmaceutically acceptable acid addition salts of such basic compounds of the invention are those that form non-toxic acid addition salts, i.e., salts containing pharmacologically acceptable anions, such as the hydrochloride, hydrobromide, hydroiodide, nitrate, sulfate, bisulfate, phosphate, acid phosphate, isonicotinate, acetate, lactate, salicylate, citrate, acid citrate, tartrate, pantothenate, bitartrate, ascorbate, succinate, maleate, gentisinate, fumarate, gluconate, glucaronate, saccharate, formate, benzoate, glutamate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate and pamoate (i.e., 1,1′-methylene-bis-(2-hydroxy-3-naphthoate)) salts.
[0213] The compounds of the invention that are acidic in nature, are capable of forming base salts with various pharmacologically acceptable cations. Examples of such salts include the alkali metal or alkaline earth metal salts and particularly, the sodium and potassium salts. This invention also encompasses pharmaceutical compositions containing, and methods of treating proliferative disorders or abnormal cell growth through administering, prodrugs of compounds of the invention. Compounds of the invention having free amino, amido, hydroxy or carboxylic groups can be converted into prodrugs. Prodrugs include compounds wherein an amino acid residue, or a polypeptide chain of two or more (e.g., two, three or four) amino acid residues is covalently joined through an amide or ester bond to a free amino, hydroxy or carboxylic acid group of compounds of the invention. The amino acid residues include but are not limited to the 20 naturally occurring amino acids commonly designated by three letter symbols and also includes 4-hydroxyproline, hydroxylysine, demosine, isodemosine, 3-methylhistidine, norvalin, beta-alanine, gamma-aminobutyric acid, citrulline homocysteine, homoserine, ornithine and methionine sulfone. Additional types of prodrugs are also encompassed. For instance, free carboxyl groups can be derivatized as amides or alkyl esters. Free hydroxy groups may be derivatized using groups including but not limited to hemisuccinates, phosphate esters, dimethylaminoacetates, and phosphoryloxymethyloxycarbonyls, as outlined in Advanced Drug Delivery Reviews, 1996, 19, 115. Carbamate prodrugs of hydroxy and amino groups are also included, as are carbonate prodrugs, sulfonate esters and sulfate esters of hydroxy groups. Derivatization of hydroxy groups as (acyloxy)methyl and (acyloxy)ethyl ethers wherein the acyl group may be an alkyl ester, optionally substituted with groups including but not limited to ether, amine and carboxylic acid functionalities, or where the acyl group is an amino acid ester as described above, are also encompassed. Prodrugs of this type are described in J. Med. Chem. 1996, 39, 10. Free amines can also be derivatized as amides, sulfonamides or phosphonamides. All of these prodrug moieties may incorporate groups including but not limited to ether, amine and carboxylic acid functionalities.
[0214] In certain combination therapies with other lipid-lowering agents, such as those described hereinbelow, e.g., HMG CoA reductase inhibitors, HMG CoA synthetase inhibitors, ACAT inhibitors, squalene synthetase inhibitors, etc., a compound of the invention may further comprise a prodrug which comprises a compound of formula 1 in a hydrolyzable linkage to another anti-cancer agent. Di-ester linkages, for example, are particularly useful for this purpose, i.e., the prodrug is in the form A 1 -C(O)O-L 1 -O(O)C-A 2 , wherein A 1 and A 2 are the two agents, L 1 is a linker such as a methylene or other (C 1 -C 6 ) alkylene group (alone or further comprising a phenyl or benzyl group). The two agents may both be a compound of the invention, or one may be another agent useful for treating, e.g., obesity, as described herein. See, e.g., U.S. Pat. No. 4,342,772-penicillins in di-ester linkages with β-lactamase inhibitors. Accordingly, a compound of the invention having an available carboxylic acid group provides just one convenient means of producing combination prodrugs of the compound of the invention, which are encompassed by this invention. Typically, the acidic conditions of the gastrointestinal tract, or enzymes localized in the cells thereof cause the hydrolysis of the prodrug, releasing both agents.
[0215] Certain compounds of the invention have asymmetric centers and therefore exist in different enantiomeric forms. All optical isomers and stereoisomers of the compounds of the invention, and mixtures thereof, are considered to be within the scope of the invention. With respect to the compounds of the invention, this invention includes the use of a racemate, one or more enantiomeric forms, one or more diastereomeric forms, or mixtures thereof. Some of the compounds of the invention may also exist as tautomers, including, e.g., keto-enol tautomers. This invention relates to the use of all such tautomers and mixtures thereof.
[0216] Furthermore, some compounds may exhibit polymorphism. It is to be understood that the present invention encompasses any and all racemic, optically-active, polymorphic and stereoisomeric forms, or mixtures thereof, which form or forms possess properties useful in the treatment of the conditions noted hereinabove, it being well known in the art how to prepare optically-active forms (for example, by resolution of the racemic form by recrystallization techniques, by synthesis from optically-active starting materials, by chiral synthesis, or by chromatographic separation using a chiral stationary phase) and how to determine efficacy for the treatment of the conditions noted herein by the standard tests described hereinafter.
[0217] The subject invention also relates to isotopically-labelled compounds of the invention which are identical to those recited in formula 1, formula 1b and formula 2 but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or mass number usually found in nature. Examples of isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine and chlorine, such as 2 H, 3 H, 13 C, 14 C, 15 N, 17 O, 18 O, 31 P, 32 P, 35 S, 18 F, and 36 Cl, respectively. Compounds of the invention and pharmaceutically acceptable salts of said compounds which contain the aforementioned isotopes and/or other isotopes of other atoms are within the scope of this invention. Certain isotopically-labelled compounds of the present invention, for example those into which radioactive isotopes such as 3 H and 14 C are incorporated, are useful in drug and/or substrate tissue distribution assays. Tritiated, i.e., 3 H, and carbon-14, i.e., 14 C, isotopes are particularly preferred for their ease of preparation and detectability. Further, substitution with heavier isotopes such as deuterium, i.e., 2 H, can afford certain therapeutic advantages resulting from greater metabolic stability, for example increased in vivo half-life or reduced dosage requirements and, hence, may be preferred in some circumstances. Isotopically labelled compounds of this invention can generally be prepared by carrying out the procedures disclosed in the Schemes and/or in the Examples below, by substituting a readily available isotopically labelled reagent for a non-isotopically labelled reagent.
[0218] The following selected functional group definitions and examples thereof are employed throughout the instant specification and the appendant claims and are offered by way of illustration, and not by limitation.
[0219] The term “alkyl” means both straight and branched chain saturated hydrocarbon groups. Some examples of alkyl groups are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl and hexyl.
[0220] The term “cycloalkyl” means both straight and branched chain saturated hydrocarbon groups comprising at least one ring or cyclic structure, and unless otherwise specified, is monocyclic. Some examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. Some examples of cycloalkenyl groups include cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl and cycloheptenyl.
[0221] The term “bicycloalkyl” means both straight and branched chain saturated hydrocarbon groups, optionally containing one or more double or triple bonds, comprising at least two rings or cyclic structures, which cyclic structures may contain one or more common carbon atoms, i.e., encompasses bridged bicyclic and spiro-bicyclic groups. Bicycloalkyl groups preferably contain from 5 to 12 members, more preferably, from 6 to 10 members. Preferably, each ring of a bicycloalkyl group contains from 3 to 6 members. An example of a bicycloalkyl group is spiro[4.5]decyl. In this application, the term “bridged” when referring to any bicyclic group means that the two rings share at least two common atoms; the shared atoms are known in the art as “bridgehead” atoms. Spiro bicyclic groups, in contrast, are bicyclic groups whose two rings share only a single bridgehead atom. Some other examples of bicycloalkyl groups are norbornyl, norbornenyl, bicyclo[3.1.0]hexyl. Bicycloalkyl groups may be in any available conformation, e.g., cis, trans, endo, exo with respect to their linkage to other groups or with respect to their substituents.
[0222] The term “alkenyl” means both straight and branched chain unsaturated hydrocarbon groups containing at least two carbons. Some examples of alkenyl groups are ethenyl, propenyl and isobutenyl.
[0223] The term “alkynyl” means both straight and branched chain hydrocarbon groups containing at least one triple bond between two carbon atoms. Some examples of alknyl groups are ethynyl and propynyl, e.g., propyn-1-yl and propyn-2-yl and propyn-3-yl.
[0224] The term “alkoxy” means a straight or branched chain hydrocarbon group attached through an oxygen atom. Some examples of alkoxy groups are methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, pentoxy, hexoxy and heptoxy.
[0225] The term “acyl” means either a straight or branched chain hydrocarbon moiety attached through a carbonyl group. Some examples of acyl groups are acetyl, propionyl, butyryl and isobutyryl.
[0226] The terms “halogen” or “halo” mean fluoro, chloro, bromo, and iodo groups, unless specified otherwise.
[0227] The term “haloalkyl”, as used herein, unless otherwise indicated, means an alkyl group substituted with one or more halo groups, on one or more carbon atoms. Preferably, the haloalkyl comprises 1 to 3 halo groups, such as a hydrocarbon comprising a dichloromethyl group, or a monohalosubstituted hydrocarbon.
[0228] The term “perfluoro”, when used in conjunction with a specified hydrocarbon group, is meant to include a substituent wherein the individual hydrogen atoms thereof are substituted therefor with fluorine atoms, preferably, wherein all the individual hydrogen atoms thereof are substituted therefor with fluorine. Some examples of perfluoro groups are trifluoromethyl (perfluoromethyl), pentafluoroethyl (perfluoroethyl) and heptafluoropropyl (perfluoropropyl).
[0229] The term “alkoxycarbonyl” means an alkoxy group attached through a carbonyl group. Some examples of alkoxycarbonyl groups are methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl and butoxycarbonyl.
[0230] The term “alkylthio” means an alkyl group attached through a sulfur atom. Some examples of alkylthio groups are methylthio, ethylthio, propylthio, isopropylthio, butylthio, isobutylthio, pentylthio and hexylthio.
[0231] The term “alkylamino” means an alkyl group attached through a nitrogen atom, wherein the nitrogen is unsubstituted, i.e., the group is alkyl-NH—. Some examples of alkylamino groups are methylamino, ethylamino, propylamino, isopropylamino, butylamino and isobutylamino.
[0232] The term “dialkylamino” means an alkylamino group wherein the nitrogen atom is substituted with two independent alkyl groups R a and R b , i.e., —N(R a R b ). Some examples of dialkylamino groups are dimethylamino, diethylamino, dipropylamino and di-isopropylamino as well as N-methyl-N′-ethylamino, N-ethyl-N′-propylamino and N-propyl-N′-isopropylamino.
[0233] Some examples of acyloxy groups include acetyloxy, propionyloxy, butyryloxy, and also include such radicals which incorporate a cyclic substituent such as benzoyloxy.
[0234] The term “haloalkoxy”, as used herein, unless otherwise indicated, means an —O-haloalkyl group wherein “haloalkyl” is as defined above. An example of a haloalkoxy group is trifluoromethoxy.
[0235] The term “aryl”, as used herein, unless otherwise indicated, means an organic radical derived from an aromatic hydrocarbon by removal of one hydrogen, such as phenyl or naphthyl. Aryl is most preferably phenyl. It is to be understood that a napthyl group may be bonded through any position, i.e., napth-1-yl, napth-2-yl, napth-3-yl, napth-4-yl.
[0236] The terms “heterocyclyl” and “heterocyclic”, as used herein, unless otherwise indicated, mean non-aromatic (saturated or unsaturated) monocyclic and multicyclic groups containing one or more heteroatoms each selected from O, S and N, wherein each ring of a heterocyclic group has from 3 to 8 atoms. Preferably, heterocyclic groups of this invention are monocyclic or bicyclic.
[0237] Monocyclic heterocyclic groups include rings having only 4 atoms; preferably, monocyclic heterocyclic groups contain from 4 to 8 members, and more preferably, from 4 to 6 members, and most preferably, 5 or 6 members. An example of a 4-membered heterocyclic group is azetidinyl (derived from azetidine), an example of a 5-membered heterocyclic group is imidazolidinyl, and an example of a 6-membered heterocyclic group is piperidinyl. Other examples of monocyclic heterocyclic groups are pyrrolidinyl, tetrahydrofuranyl, tetrahydrothienyl, tetrahydropyranyl, tetrahydrothiopyranyl, morpholino, thiomorpholino, thioxanyl, piperazinyl, 1,2,3,6-tetrahydropyridinyl, pyrrolinyl, 2H-pyranyl, 4H-pyranyl, 1,4-dioxanyl, 1,3-dioxolanyl, 1,4-dithianyl, pyrazolinyl, pyrazolidinyl, dihydropyranyl, dihydrothienyl, dihydrofuranyl and imidazolinyl. Other examples of monocyclic heterocyclic groups include azacycloheptane and azacyclooctane. Preferred monocyclic heterocyclic groups are azetidinyl, pyrrolidinyl, piperidinyl and morpholino. Monocyclic heterocyclic groups may be referred to herein as “heteromonocyclyl.”
[0238] Bicyclic heterocyclic groups may be referred to herein as “heterobicyclic” or “heterobicyclyl”, both of which as used herein mean heterocyclic groups containing two rings, and encompass fused-ring bicyclic, bridged bicyclic and spiro-bicyclic groups. Heterobicyclic groups preferably contain from 5 to 12 members, more preferably, from 6 to 10 members. Preferably, each ring of a heterobicyclic group contains from 3 to 6 members. An example of a heterobicyclic group is 1,4-dioxaspiro[4.5]decyl. Some other examples of heterobicyclic groups include azabicyclohexyl, e.g., 3-azabicyclo[3.1.0]hexyl, azabicycloheptyl, e.g., 2-azabicyclo[2.2.1]heptyl and azabicyclooctyl.
[0239] The term “heteroaryl” as used herein means aromatic heterocyclic groups comprising from 5 to 12 atoms and containing one or more heteroatoms each selected from O, S and N, wherein each ring of the heteroaryl group contains from 3 to 8 atoms. Heteroaryl groups of this invention unless otherwise indicated may contain one ring or more than one ring, i.e., they may be monocyclic or multicyclic, for example bicyclic, so long as at least one ring in a multicyclic group is aromatic. Preferably, heteroaryl groups of this invention are monocyclic or bicyclic. Preferably, each ring of a heteroaryl group contains one or two heteroatoms. Monocyclic heteroaryl groups preferably contain from 5 to 8 members, more preferably, 5 or 6 members. Preferably, the monocyclic heteroaryl groups containing two heteratoms contain two nitrogen atoms, a nitrogen atom and an oxygen atom, or a nitrogen atom and a sulfur atom. Some examples of monocyclic heteroaryl groups are pyridinyl, imidazolyl, pyrimidinyl, pyrazolyl, triazolyl, pyrazinyl, tetrazolyl, furyl, thiophenyl (referred to hereinafter as “thienyl”), isoxazolyl, thiazolyl, oxazolyl, isothiazolyl, pyrrolyl, oxadiazolyl, thiadiazolyl and furazanyl (i.e., 2,5-diaza-furanyl). Preferred among the monocyclic heteroaryl groups are thienyl, furyl and pyridinyl. More preferred monocyclic heteroaryl groups are thien-2-yl, fur-2-yl, pyridin-2-yl, pyridin-3-yl, i.e., attached through the 2- or 3-carbon, respectively. A particularly preferred monocyclic heteroaryl group is pyridyl. The term “pyridyl” as used in this application, unless otherwise specified, means 2-pyridyl, 3-pyridyl or 4-pyridyl, i.e., pyridyl attached through any available carbon atom.
[0240] Multicyclic heteroaryl groups are preferably bicyclic; bicyclic heteroaryl groups preferably contain 9 or 10 members. Some examples of heteroaryl groups are quinolinyl, isoquinolinyl, indolyl, 3H-indolyl, indolinyl, benzimidazolyl, benzofuranyl, cinnolinyl, indazolyl, indolizinyl, phthalazinyl, pyridazinyl, triazinyl, isoindolyl, purinyl, benzofurazanyl, benzothiophenyl, benzothiazolyl, benzisothiazolyl, benzoxazolyl, pteridinyl, benzothiadiazine, benzothiazinyl, 2H-1-benzopyranyl, chromanyl, benzoxazolyl, quinazolinyl, quinoxalinyl, naphthyridinyl, and furopyridinyl.
[0241] The foregoing heterocyclic and heteroaryl groups may be C-attached or N-attached where such is possible. For instance, pyrrolyl may be pyrrol-1-yl (N-attached) or pyrrol-3-yl (C-attached). The heterocyclic groups of this invention also include ring systems substituted with one or more oxo moieties.
[0242] The term “treating”, as used herein, unless otherwise indicated, means reversing, alleviating, inhibiting the progress of, or preventing the disorder or condition to which such term applies, or one or more symptoms of such disorder or condition. The term “treatment”, as used herein, unless otherwise indicated, refers to the act of treating, as “treating” is defined immediately above.
[0243] The invention further relates to a pharmaceutical composition comprising a compound of formula 1 and a pharmaceutically acceptable carrier. The pharmaceutical composition may, for example, be in a form suitable for oral administration as a tablet, capsule, pill, powder, sustained release formulations, solution, suspension, for parenteral injection as a sterile solution, suspension or emulsion, for topical administration as an ointment or cream or for rectal administration as a suppository. The pharmaceutical composition may be in unit dosage forms suitable for single administration of precise dosages. The pharmaceutical composition will include a conventional pharmaceutical carrier or excipient and a compound according to the invention as an active ingredient. In addition, it may include other medicinal or pharmaceutical agents, carriers, adjuvants, etc.
[0244] Suitable pharmaceutical carriers include inert diluents or fillers, water and various organic solvents. The pharmaceutical compositions may, if desired, contain additional ingredients such as flavorings, binders, excipients and the like. Thus for oral administration, tablets containing various excipients, such as citric acid may be employed together with various disintegrants such as starch, alginic acid and certain complex silicates and with binding agents such as sucrose, gelatin and acacia. Additionally, lubricating agents such as magnesium stearate, sodium lauryl sulfate and talc are often useful for tableting purposes. Solid compositions of a similar type may also be employed in soft and hard filled gelatin capsules. Preferred materials, therefor, include lactose or milk sugar and high molecular weight polyethylene glycols. When aqueous suspensions or elixirs are desired for oral administration the active compound therein may be combined with various sweetening or flavoring agents, coloring matters or dyes and, if desired, emulsifying agents or suspending agents, together with diluents such as water, ethanol, propylene glycol, glycerin, or combinations thereof.
[0245] Exemplary parenteral administration forms include solutions or suspensions of active compounds in sterile aqueous solutions, for example, aqueous propylene glycol or dextrose solutions. Such dosage forms can be suitably buffered, if desired. Aqueous compositions of the present invention may comprise other pharmaceutically acceptable solutes including additives and other therapeutic agents, as appropriate. Suitable additives are those well known in the art including, but not limited to, antioxidants, antibacterials, surfactants, chelating agents, sugars, and preservatives. Aqueous compositions of the invention can be administered by injection, which can be intramuscular, intravenous or preferably subcutaneous. A dose of from about 0.5 μg/Kg/day to about 10 μg/Kg/day, preferably from about 1 μg/Kg/day to 5 μg/Kg/day, can be used.
[0246] Methods of preparing various pharmaceutical compositions with a specific amount of active compound are known, or will be apparent, to those skilled in this art. For examples, see Remington: The Practice of Pharmacy , Lippincott Williams and Wilkins. Baltimore Md. 20 th ed. 2000.
[0247] The compounds of the invention can be administered alone but will generally be administered in an admixture with suitable pharmaceutical excipient(s), diluent(s) or carrier known in the art and selected with regard to the intended route of administration and standard pharmaceutical practice. If appropriate “auxiliary” agents may also be added, which includes preservatives, anti-oxidants, flavors or colorants. The compound of the invention may be formulated to provide immediate-, delayed-, modified-, sustained-, pulsed- or controlled-release dependent on the specific route of administration and the specificity of release profile, commensurate with therapeutic needs.
[0248] The compounds of the invention can be administered, for example but not limited to, the following route: oral (including buccal, sublingual, etc.) in the forms that are well known in the art (ref.) for veterinary and pharmaceutical applications. “Oral” in this instance refers to oral mode of administration wherein the forms are explicitly provided to the animals for oral consumption i.e., on-diet, in-drinking fluid, placed directly into the oral cavity, or offered for free-choice consumption. In this invention, the term “animal” includes a warm-blooded animal of the animal kingdom possessed of a homeostatic mechanism and includes mammals and birds, preferably companion animals and livestock animals, and humans. Some examples of companion animals are canines, e.g., dogs, felines, e.g., cats and horses; some examples of livestock animals are pigs, cows, sheep and the like. Preferably, the animal is a mammal. More preferably, the mammal is a companion animal or a livestock animal.
[0249] Typical oral solid forms may include tablets, powders, multi-particulate preparations (granules), capsules, chews, lozenges, films, patches, etc. Typical oral liquid (including semi-solid and colloidal) forms may include solutions, elixirs, gels, sprays, liquid-filled chews, etc. Other oral forms wherein the active agent is suspended in a liquid or semi-solid carrier phase, for example suspensions, may also be used.
[0250] The preferred oral solid, liquid and suspension forms for a compound of the invention are those that impart flexibility in dosing to the animals, wherein the method of administration is facile and the dose can be accurately and flexibly controlled in keeping with the need of the therapy. Examples of such forms include tablet preparations, solutions (and similar forms thereof as described herein) and suspensions. In these examples, the dose can be easily controlled for oral administration. Particularly for solutions and suspensions, the utility of appropriate metering systems (i.e., calibrated syringes etc.) provides high flexibility in controlling the dose to facilitate administration to animal species of different sizes or to different animal species or breeds, with varying dose requirements. Additionally, the utility of flavoring/palatability agents and/or texture enhancers in the said forms can promote animal acceptance and compliance, which can be particularly advantageous when dosing chronically to animals.
[0251] The compounds of the invention may also be administered via the parenteral routes. The term parenteral in this context refers to all routes of drug administration that is not via the oral cavity. Preferably for the compounds of the innovation, parenteral routes may include topical and transdermal, rectal, vaginal, nasal, inhalation and injectables (i.e., administration modes that require penetration of the skin barrier via needle and needle-less methods, including implants and reservoirs). Formulations for these routes of administration may be prepared in a conventional manner in accordance with standard pharmaceutical and veterinary practices, illustrative examples of which are described herein.
[0252] Particularly preferred compositions of the compounds of the invention comprise oral solid forms, examples of which are provided below, are preferably tablets, powders or granules which typically contain just the active agent(s) or preferably in combination with adjuvants/excipients.
[0253] In an embodiment of the invention, the pharmaceutical composition comprises a compound the invention, herein referred to also as “the active” in an amount typically less than 50% (by weight) of the formulation and preferably less than 10%, more preferably, about 2.5% by weight, and a pharmaceutically acceptable carrier. In a preferred embodiment, the predominant portion of the formulation comprises fillers, diluents, disintegrants, lubricants and optionally, flavors. The composition of these excipients is well known in the art. In an embodiment of the invention, the preferred fillers/diluents comprise admixtures of two or more of the following components: avicel, mannitol, lactose (all types), starch, and di-calcium phosphate. In preferred embodiments of the compositions, the filler/diluent admixtures typically comprises less than 98% (by weight) of the formulation and preferably less than 95%, for example 93.5%. In a preferred embodiment, disintegrants include Ac-di-sol, Explotab™ starch and sodium lauryl sulphate (SLS)—also known as wetting agent. In a more preferred embodiment, the amount of filler/diluent admixture usually comprises less than 10% (by weight) of the composition and preferably less than 5%; in a particularly preferred embodiment, the amount is about 3%. In a particularly preferred embodiment, the lubricant is magnesium stearate. In preferred embodiments thereof, the magnesium stearate is present in an amount less than about 5% of the formulation and preferably less than about 3%, more preferably, about 1%. Preferably, lubricants comprise less than 60% of the formulation, preferably less than 40%, and most preferably, from about 10% to about 20%. Particularly preferred embodiments of tablet formulations for the compounds of the invention are shown in Table 10.
[0254] The compositions of the invention include tablets. In a preferred embodiment, tablets are manufactured by a process selected from direct compression or a wet, dry or melt granulation, melt congealing process and extrusion. In another embodiment, tablet cores of the compositions of the invention may be mono or multi-layer(s) and can be coated with appropriate overcoats known in the art.
[0255] Oral liquid forms of the compounds of the invention are preferably solutions, wherein the active compound is fully dissolved. In an embodiment, the solution comprises the active and a pharmaceutically precedented solvents suitable for oral administration. In a preferred embodiment, the solvent is one in which the compounds of the invention show good solubility. In a more preferred embodiment, the solution comprises a solvent selected from polyethylene glycol, polypropylene glycol, edible oils and glyceryl- and glyceride-based systems. In more preferred embodiments, glyceryl- and glyceride-based systems comprise agents selected from Captex 355 EP, Crodamol GTC/C, or Labrafac CC, triacetin, Capmul CMC, Migyols (812, 829, 840), Labrafil M1944CS, Peceol and Maisine 35-1. The exact composition of these agents and commercial sources are shown in Table 11. These solvents usually make up the predominant portion of the formulation i.e., greater than 50% (by weight) and preferably greater than 80%, for example 95% and more preferably greater than 99%. In preferred embodiments, the solution further comprises an adjuvant or additives. In a preferred embodiment thereof, the additive or adjuvant is a taste-mask agent, palatability agent, flavoring agent, antioxidant, stabilizer, texture modifier, viscosity modifier, or a solubilizer.
[0256] A further embodiment is a process for preparing preferred oral liquid form of the compounds of the invention (see the Pharmaceutical Compositions section), wherein the individually preferred components are combined optionally with mechanical or ultrasonic agitation in a preferred temperature range, in such a fashion that is advantageous to the rate of dissolution.
[0257] The compounds of the instant invention inhibit or decrease Apo B secretion, likely by the inhibition of MTP, although it may be possible that other mechanisms are involved. The compounds are useful in treating any of the disease states or conditions in which Apo B, serum cholesterol, and/or triglyceride levels are elevated. Thus, the compositions of this invention are useful for the treatment of conditions including atherosclerosis, pancreatitis, obesity, hypercholesterolemia, hypertriglyceridemia, hyperlipidemia and diabetes. Accordingly, this invention provides pharmaceutical compositions comprising a therapeutically effective amount of a compound of the invention, including the stereoisomers, pharmaceutically acceptable salts and solvates thereof, in combination with a pharmaceutically acceptable carrier or diluent.
[0258] The instant invention also relates to a method for inhibiting or decreasing Apo B secretion in an animal in need thereof which comprises the administration of an Apo B secretion inhibiting or decreasing amount of a compound of the invention or a stereoisomer, pharmaceutically acceptable salt or solvate thereof. The invention further provides a method of treating a condition selected from atherosclerosis, pancreatitis, obesity, hypercholesterolemia, hypertriglyceridemia, hyperlipidemia, and diabetes which comprises administering to an animal in need of such treatment a therapeutically effective amount of a compound of formula 1 (or 1b or 2) or a stereoisomer, pharmaceutically acceptable salt or solvate thereof. A preferred subgroup of the conditions described hereinabove is atherosclerosis, obesity, hypercholesterolemia, hypertriglyceridemia, hyperlipidemia, and diabetes.
[0259] In one aspect, the present invention concerns the treatment of diabetes, including impaired glucose tolerance, insulin resistance, insulin dependent diabetes mellitus (Type I) and non-insulin dependent diabetes mellitus (NIDDM or Type II). Also included in the treatment of diabetes are the diabetic complications, such as neuropathy, nephropathy, retinopathy or cataracts.
[0260] Diabetes can be treated by administering to an animal having diabetes (Type I or Type II), insulin resistance, impaired glucose tolerance, or any of the diabetic complications such as neuropathy, nephropathy, retinopathy or cataracts, a therapeutically effective amount of a compound of the present invention. It is also contemplated that diabetes be treated by administering a compound of the invention along with other agents that can be used to treat diabetes. Preferably, the diabetes is Type II diabetes. More preferably, the animal is feline; even more preferably, the feline is a cat.
[0261] Accordingly, this invention further relates to a method of treating Type II diabetes in an animal in need of such treatment, which comprises administering to the animal a therapeutically effective amount of a compound of formula 1 or a stereoisomer, pharmaceutically acceptable salt or solvate thereof.
[0262] The invention also provides a method of treating Type II diabetes in an animal in need of such treatment, which comprises administering to the animal a therapeutically effective amount of a compound of formula 1 or a stereoisomer, pharmaceutically acceptable salt or solvate thereof, in combination with one or more additional agents capable of treating Type II diabetes in the animal.
[0263] Representative agents that can be used to treat diabetes include insulin and insulin analogs (e.g. LysPro insulin); GLP-1 (7-37) (insulinotropin) and GLP-1 (7-36)-NH 2 ; sulfonylureas and analogs: chlorpropamide, glibenclamide, tolbutamide, tolazamide, acetohexamide, Glypizide®, glimepiride, repaglinide, meglitinide; biguanides: metformin, phenformin, buformin; α2-antagonists and imidazolines: midaglizole, isaglidole, deriglidole, idazoxan, efaroxan, fluparoxan; other insulin secretagogues: linogliride, A-4166; glitazones: ciglitazone, pioglitazone, englitazone, troglitazone, darglitazone, BRL49653; fatty acid oxidation inhibitors: clomoxir, etomoxir; α-glucosidase inhibitors: acarbose, miglitol, emiglitate, voglibose, MDL-25,637, camiglibose, MDL-73,945; β-agonists: BRL 35135, BRL 37344, Ro 16-8714, ICI D7114, CL 316,243; phosphodiesterase inhibitors: L-386,398; lipid-lowering agents: benfluorex; antiobesity agents: fenfluramine and orlistat; vanadate and vanadium complexes (e.g. Naglivan®) and peroxovanadium complexes; amylin antagonists; glucagon antagonists; gluconeogenesis inhibitors; somatostatin analogs; antilipolytic agents: nicotinic acid, acipimox, WAG 994; and glycogen phosphorylase inhibitors, such as those disclosed in WO 96/39385 and WO 96/39384. Also contemplated in combination with compounds of the invention are pramlintide acetate (Symlin™) and nateglinide. Any combination of agents can be administered as described above.
[0264] The invention also relates to a method of treating obesity in a mammal which comprises administering to an animal in need of such treatment an effective amount of an intestinal-MTP-selective compound, wherein the ED 25 of the compound for the inhibition of intestinal fat absorption is at least 5-fold lower than the ED 25 of the compound for the lowering of serum triglycerides. In an embodiment, the ED 25 for the inhibition of intestinal fat absorption is at least 10-fold lower than the ED 25 of the compound for the lowering of serum triglycerides. In another embodiment, the compound exhibits an ED 25 for the inhibition of intestinal fat absorption which is at least 50-fold lower than the ED 25 of the compound for the lowering of serum triglycerides.
[0265] In another embodiment, the intestinal-MTP-selective compound is a compound of formula 1, 1b or 2, or an embodiment, preferred embodiment, more preferred embodiment, or particularly preferred embodiment of a compound of formula 1, 1b or 2.
[0266] In this invention, the term “selectivity” refers to a greater effect of a compound in a first assay, compared to the effect of the same compound in a second assay. In the above embodiment of the invention, the first assay is for the ability of the compound to inhibit intestinal fat absorption and the second assay is for the ability of the compound to lower serum triglycerides. In a preferred embodiment, the ability of the compound to inhibit intestinal fat absorption is measured by the ED 25 of the compound in an intestinal fat absorption assay, such that a greater effect of the compound results in the observation of a lower absolute (numerical) value for the ED 25 . In another preferred embodiment, the ability of the compound to lower serum triglycerides is measured by the ED 25 of the compound in a serum triglyceride assay. Again, a greater effect of a compound in the serum triglyceride lowering assay results in the observation of a lower absolute (numerical) value for the ED 25 . An illustrative example of each assay is provided hereinbelow, but it is to be understood that any assay capable of measuring the effectiveness of a compound in inhibiting intestinal fat absorption, or capable of measuring the effectiveness of a compound in lowering serum triglycerides, is encompassed by the present invention.
[0267] In a particularly preferred embodiment, the intestinal-MTP-selective compound is a compound of formula 1b, wherein X 1 is N(R 4 ) or O, X 2 is C(H); m, n and p are all 0; R 3 is H or Cl; R 4 is CH 3 ; R 5 and R 9 are both H; R 10 is phenyl (with carbons numbered 1′-6′) substituted at the 4′-position with CF 3 , or R 10 is (C 1 -C 6 )alkoxy; R 6 is H or methyl and R 7 is (C 1 -C 6 )alkyl or benzyl, wherein the benzyl is optionally substituted with (C 1 -C 6 )alkyl or (C 1 -C 6 )alkoxy.
[0268] The compounds of this invention may be used in conjunction with other pharmaceutical agents, including other lipid lowering agents. Such agents include, for example, cholesterol biosynthesis inhibitors and cholesterol absorption inhibitors, especially HMG-CoA reductase inhibitors and HMG-CoA synthase inhibitors; HMG-CoA reductase gene expression inhibitors; CETP inhibitors; bile acid sequestrants; fibrates; cholesterol absorption inhibitors; ACAT inhibitors, squalene synthetase inhibitors, ion-exchange resins, anti-oxidants and niacin. In combination therapy treatment, the compounds of the instant invention and the other drug therapies may be administered to animals (e.g. humans) by conventional methods.
[0269] This invention provides a method of treating atherosclerosis; pancreatitis secondary to hypertriglyceridemia; hyperglycemia (1) by causing a reduced absorption of dietary fat through MTP inhibition, (2) by lowering triglycerides through MTP inhibition or (3) by decreasing the absorption of free fatty acids through MTP inhibition; in an animal in need of treatment thereof, which comprises administering to the animal a therapeutically effective amount of the compound of formula 1, 1b or 2.
[0270] The invention also provides a pharmaceutical composition comprising: a) a therapeutically effective amount of a first compound, wherein said first compound is a compound of claim 1 or a stereoisomer, pharmaceutically acceptable salt or hydrate thereof; b) a therapeutically effective amount of a second compound, wherein said second compound is selected from a cholesterol absorption inhibitor, a CETP inhibitor, an HMG-CoA reductase inhibitor, an HMG-CoA synthase inhibitor, an inhibitor of HMG-CoA reductase gene expression, niacin, an antioxidant, an ACAT inhibitor or a squalene synthetase inhibitor; and c) a pharmaceutically acceptable carrier or diluent. In a preferred embodiment of the invention, the said second compound is selected from lovastatin, simvastatin, pravastatin, fluvastatin, atorvastatin or rivastatin. In a more preferred embodiment of the invention, said second compound is atorvastatin.
[0271] Specific cholesterol absorption inhibitors and cholesterol biosynthesis inhibitors are described in detail hereinbelow. Additional cholesterol absorption inhibitors are known to those skilled in the art and are described, for example, in PCT WO 94/00480.
[0272] Any HMG-CoA reductase inhibitor may be employed as the second compound in the combination therapy aspect of the instant invention. The term HMG-CoA reductase inhibitor refers to a compound which inhibits the biotransformation of hydroxymethylglutaryl-coenzyme A to mevalonic acid as catalyzed by the enzyme HMG-CoA reductase. Such inhibition may be determined readily by one of skill in the art according to standard assays (e.g., Methods of Enzymology, 1981; 71: 455-509 and the references cited therein). A variety of these compounds are described and referenced hereinbelow. U.S. Pat. No. 4,231,938 (the disclosure of which is hereby incorporated by reference) discloses certain compounds isolated after cultivation of a microorganism belonging to the genus Aspergillus , such as lovastatin. Also, U.S. Pat. No. 4,444,784 (the disclosure of which is hereby incorporated by reference) discloses synthetic derivatives of the aforementioned compounds, such as simvastatin. Additionally, U.S. Pat. No. 4,739,073 (the disclosure of which is hereby incorporated by reference) discloses certain substituted indoles, such as fluvastatin. Further, U.S. Pat. No. 4,346,227 (the disclosure of which is hereby incorporated by reference) discloses ML-236B derivatives, such as pravastatin. In addition, EP 491,226 teaches certain pyridyldihydroxyheptenoic acids, such as rivastatin. Also, U.S. Pat. No. 4,647,576 (the disclosure of which is hereby incorporated by reference) discloses certain 6-[2-(substituted-pyrrol-1-yl)alkyl]-pyran-2ones such as atorvastatin. Other HMG-CoA reductase inhibitors will be known to those skilled in the art.
[0273] Any HMG-CoA synthase inhibitor may be used as the second compound in the combination therapy aspect of this invention. The term HMG-CoA synthase inhibitor refers to a compound which inhibits the biosynthesis of hydroxymethylglutaryl-coenzyme A from acetyl-coenzyme A and acetoacetyl-coenzyme A, catalyzed by the enzyme HMG-CoA synthase. Such inhibition may be determined readily by one of skill in the art ac cording to standard assays (e.g., Methods of Enzymology, 1975; 35: 155-160 and Methods of Enzymology, 1985; 110: 19-26 and the references cited therein). A variety of these compounds are described and referenced hereinbelow. U.S. Pat. No. 5,120,729 (the disclosure of which is hereby incorporated by reference) discloses certain beta-lactam derivatives. U.S. Pat. No. 5,064,856 (the disclosure of which is hereby incorporated by reference) discloses certain spiro-lactone derivatives prepared by culturing the microorganism MF5253. U.S. Pat. No. 4,847,271 (the disclosure of which is hereby incorporated by reference) discloses certain oxetane compounds such as 11-(3hydroxymethyl-4-oxo-2-oxetayl)-3,5,7-trimethyl-2,4-undecadienoic acid derivatives. Other HMG-CoA synthase inhibitors will be known to those skilled in the art.
[0274] Any compound that decreases HMG-CoA reductase gene expression may be used as the second compound in the combination therapy aspect of this invention. These agents may be HMG-CoA reductase transcription inhibitors that block the transcription of DNA or translation inhibitors that prevent translation of mRNA coding for HMG-CoA reductase into protein.
[0275] Such inhibitors may either affect transcription or translation directly, or may be biotransformed into compounds that have the aforementioned attributes by one or more enzymes in the cholesterol biosynthetic cascade or may lead to the accumulation of an isoprene metabolite that has the aforementioned activities. Such regulation is readily determined by those skilled in the art according to standard assays (Methods of Enzymology, 1985; 110: 9-19). Several such compounds are described and referenced below however other inhibitors of HMG-CoA reductase gene expression will be known to those skilled in the art U.S. Pat. No. 5,041,432 (the disclosure of which is incorporated herein by reference) discloses certain 15-substituted lanosterol derivatives. Other oxygenated sterois that suppress the biosynthesis of HMG-CoA reductase are discussed by E. I. Mercer (Prog. Up. Res., 1993; 32: 357-416).
[0276] Any compound having activity as a CETP inhibitor can serve as the second compound in the combination therapy aspect of the instant invention. The term CETP inhibitor refers to compounds which inhibit the cholesteryl ester transfer protein (CETP) mediated transport of various cholesteryl esters and triglycerides from high density lipoprotein (HDL) to low density lipoprotein (LDL) and very low density lipoprotein (VLDL). A variety of these compounds are described and referenced hereinbelow however other CETP inhibitors will be known to those skilled in the art U.S. Pat. No. 5,512,548 (the disclosure of which is incorporated herein by reference) discloses certain polypeptide derivatives having activity as CETP inhibitors, while certain CETP-inhibitory rosenonolactone derivatives and phosphate-containing analogs of cholesteryl ester are disclosed in J. Antibiot., 1996; 49(8): 815-816, and Bioorg. Med. Chem. Left; 1996; 6: 1951-1954, respectively.
[0277] Any ACAT inhibitor can serve as the second compound in the combination therapy aspect of this invention. The term ACAT inhibitor refers to compounds which inhibit the intracellular esterification of dietary cholesterol by the enzyme acyl CoA:cholesterol acyltransferase. Such inhibition may be determined readily by one of skill in the art according to standard assays, such as the method of Heider et al. described in Journal of Lipid Research., 1983; 24: 1127. A variety of these compounds are described and referenced hereinbelow however other ACAT inhibitors will be known to those skilled in the art.
[0278] U.S. Pat. No. 5,510,379 (the disclosure of which is incorporated by reference) discloses certain carboxysulfonates, while WO 96/26948 and WO 96/10559 both disclose urea derivatives having ACAT inhibitory activity.
[0279] Any compound having activity as a squalene synthetase inhibitor can serve as the second compound in the combination therapy aspect of the instant invention. The term squalene synthetase inhibitor refers to compounds that inhibit the condensation of two molecules of farnesylpyrophosphate to form squalene, a reaction that is catalyzed by the enzyme squalene synthetase. Such inhibition is readily determined by those skilled in the art according to standard methodology (Methods of Enzymology 1969; 15: 393-454 and Methods of Enzymology 1985; 110: 359-373 and references cited therein). A summary of squalene synthetase inhibitors has been complied (Curr. Op. Ther. Patents (1993) 861-4). European patent application publication No. 0 567 026 A1 discloses certain 4,1-benzoxazepine derivatives as squalene synthetase inhibitors and their use in the treatment of hypercholesterolemia and as fungicides. European patent application publication No. 0 645 378 A1 discloses certain seven- or eight-membered heterocycles as squalene synthetase inhibitors and their use in the treatment and prevention of hypercholesterolemia and fungal infections. European patent application publication No. 0 645 377 A1 discloses certain benzoxazepine derivatives as squalene synthetase inhibitors useful for the treatment of hypercholesterolemia or coronary sclerosis. European patent application publication No. 0 611 749 A1 discloses certain substituted amino acid derivatives useful for the treatment of arteriosclerosis. European patent application publication No. 0 705 607 A2 discloses certain condensed seven- or eight-membered heterocyclic compounds useful as antihypertriglyceridemic agents. PCT publication WO96/09827 discloses certain combinations of cholesterol absorption inhibitors and cholesterol biosynthesis inhibitors including benzoxazepine derivatives and benzothiazepine derivatives. European patent application publication No. 0 071 725 A1 discloses a process for preparing certain optically-active compounds, including benzoxazepine derivatives, having plasma cholesterol and triglyceride lowering activities.
[0280] The present invention also provides a method of treating obesity in an animal, which comprises administering to the obese animal a compound of this invention in combination with another anti-obesity agent.
[0281] The other anti-obesity agents is preferably selected from the group consisting of a β 3 -adrenergic receptor agonist, a cholecystokinin-A (CCK-A) agonist, a monoamine reuptake inhibitor (such as sibutramine), a sympathomimetic agent, a serotoninergic agent (such as fenfluramine or dexfenfluramine), a dopamine agonist (such as bromocriptine), a melanocyte-stimulating hormone receptor agonist or mimetic, a melanocyte-stimulating hormone receptor analog, a cannabinoid receptor antagonist, a melanin concentrating hormone antagonist, leptin, a leptin analog, a leptin receptor agonist, a galanin antagonist, a lipase inhibitor (such as orlistat), a bombesin agonist, a neuropeptide-Y antagonist such as NPY-1 or NPY-5, a thyromimetic agent, dehydroepiandrosterone or an analog thereof, a glucocorticoid receptor agonist or antagonist, an orexin receptor antagonist, a urocortin binding protein antagonist, a glucagon-like peptide-1 receptor agonist, and a ciliary neurotrophic factor such as Axokine, or a human agouti-related protein (AGRP) antagonist. Other anti-obesity agents are also known, or will be apparent in light of this disclosure, to one of ordinary skill in the art.
[0282] Especially preferred anti-obesity agents comprise those compounds selected from the group consisting of sibutramine, fenfluramine, dexfenfluramine, bromocriptine, phentermine, ephedrine, leptin, phenylpropanolamine pseudoephedrine, {4-[2-(2-[6-aminopyridin-3-yl]-2(R)-hydroxyethylamino)ethoxy]phenyl}acetic acid, {4-[2-(2-[6-aminopyridin-3-yl]-2(R)-hydroxyethylamino)ethoxy]phenyl}benzoic acid, {4-[2-(2-[6-aminopyridin-3-yl]-2(R)-hydroxyethylamino)ethoxy]phenyl}propionic acid, and {4-[2-(2-[6-aminopyridin-3-yl]-2(R)-hydroxyethylamino)ethoxy]phenoxy}acetic acid.
[0283] In preferred embodiments, the additional anti-obesity agent is another MTP/apoB inhibitor selected from the group consisting of (i) BMS-197636, also known as 9-[4-[4-(2,3-dihydro-1-oxo-1H-isoindol-2-yl)-1-piperidinyl]butyl]-N-propyl-9H-fluorene-9-carboxamide; (ii) BMS-200150, also known as 2-[1-(3,3-diphenylpropyl)-4-piperidinyl]-2,3-dihydro-1H-isoindol-1-one; and (iii) BMS 201038, also known as 9-[4-(4-[2-(4-trifluoromethylphenyl)benzoylamino]piperidin-1-yl)butyl]-N-2,2,2-trifluoroethyl)-9H-fluorene-9-carboxamide; and the pharmaceutically acceptable salts of (i), (ii) and (iii). In another embodiment, the anti-obesity agent is selected from the agents disclosed in European patent application publication Nos. 0 584 446 A2 and 0 643 057 A1, the latter of which discloses certain compounds of the formulas
which have utility as inhibitors of MTP, wherein the substituents listed in formula Ob1 are as defined in EP 0 643 057 A1. In another embodiment, the anti-obesity agent is selected from the agents disclosed in European patent application publication Nos. 1 099 439 A2, which discloses certain compounds of the formula
wherein L in formula Ob2 is as defined as in EP 1 099 439 A2.
[0284] Preferred compounds of those disclosed in 1 099 439 A2 are compounds selected from the group consisting of 4′-trifluoromethyl-biphenyl-2-carboxylic acid-(2-butyl-1,2,3,4-tetrahydroisoquinolin-6-yl)-amide and 4′-trifluoromethyl-biphenyl-2-carboxylic acid-(2-(2-acetylaminoethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-amide.
[0285] Methods for preparing the above agents are publicly available; for example, phentermine may be prepared as described in U.S. Pat. No. 2,408,345; sibutramine may be prepared as in U.S. Pat. No. 4,929,629; orlistat may be prepared as in U.S. Pat. No. 4,598,089; fenfluramine and dexfenfluramine may be prepared as described in U.S. Pat. No. 3,198,834; bromocriptine may be prepared as described in U.S. Pat. Nos. 3,752,814 and 3,752,888; and the substituted amino pyridines listed above may be prepared as described in PCT International Publication No. WO 96/35671; the disclosure of each of these publications is herein incorporated by reference.
[0286] It will be appreciated by those skilled in the art that certain compounds of the instant invention may contain an asymmetrically-substituted carbon atom and accordingly may exist in, and/or be isolated in, optically-active and racemic forms. Furthermore, some compounds may exhibit polymorphism. It is to be understood that the present invention encompasses any and all racemic, optically-active, polymorphic and stereoisomeric forms, or mixtures thereof, which form or forms possess properties useful in the treatment of the conditions noted hereinabove, it being well known in the art how to prepare optically-active forms (for example, by resolution of the racemic form by recrystallization techniques, by synthesis from optically-active starting materials, by chiral synthesis, or by chromatographic separation using a chiral stationary phase) and how to determine efficacy for the treatment of the conditions noted herein by the standard tests described hereinafter.
[0287] The present invention may be understood more fully by reference to the detailed description and illustrative examples, which are intended to exemplify non-limiting embodiments of the invention. The term “compound of formula 1”, “compound of formula 2,” as used herein, e.g., “a pharmaceutical composition comprising a compound of formula 1 . . . ” encompasses in addition to their generic description of the compound, all of the embodiments, preferred embodiments, more preferred embodiments and particularly preferred embodiments of the compounds, as well as each of the Examples described below.
BRIEF DESCRIPTION OF DRAWINGS
[0288] FIG. 1 shows the X-ray powder diffraction pattern of a sample of preferred Form A of the title compound described in Example 44. Detailed conditions for the preparation of the sample are provided in Example 44. The pattern was obtained on a Siemens D5000, Cu anode, variable slit, range 2-55, step size: 0.02; ambient temperature.
[0289] FIG. 2 shows the results of thermal analysis of preferred Form A of the title compound described in Example 44 by differential scanning calorimetry. The peak is 144.068° C.; peak height, 3.8001 mW; peak area 108.368 mJ; Delta H 37.485 J/g; Onset 133.524° C. The analysis was performed under nitrogen gas flow; after holding at 40° C. for 1 minute, heating from 40.00° C. to 200.00° C. at a rate of 20° C./minute. The sample size was 2.891 mg.
[0290] FIG. 3 shows the X-ray powder diffraction pattern of a sample of preferred Form B of the title compound described in Example 44. Detailed conditions for the preparation of the sample are provided in Example 44. The pattern was obtained on a Siemens D5000, Cu anode, variable slit, range 2-55, step size: 0.02; ambient temperature.
[0291] FIG. 4 shows the X-ray powder diffraction pattern of a sample of preferred Form G of the title compound described in Example 44. Detailed conditions for the preparation of the sample are provided in Example 44. The pattern was obtained on a Siemens D5000, Cu anode, variable slit, range 2-55, step size: 0.02; ambient temperature.
[0292] FIG. 5 shows the X-ray powder diffraction pattern of a sample of preferred Form F of the title compound described in Example 44. Detailed conditions for the preparation of the sample are provided in Example 44. The pattern was obtained on a Siemens D5000, Cu anode, variable slit, range 2-55, step size: 0.02; ambient temperature.
[0293] FIG. 6 shows the X-ray powder diffraction pattern of a sample of the intermediate compound 1-Methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid potassium salt 2.6 hydrate, prepared in Example 44 step (d) alternative C. Detailed conditions for the preparation of the sample are provided in Example 44. The pattern was obtained on a Siemens D5000, Cu anode, variable slit, range 2-55, step size: 0.02; ambient temperature.
DETAILED DESCRIPTION OF THE INVENTION
[0294] The following examples illustrate the compositions and methods of the present invention. It is to be understood that the present invention is not limited to the specific details of the Examples provided below.
[0295] In the discussion which follows, certain common chemical and procedural abbreviations and acronyms therefor have been employed which include: Me (methyl); Et (ethyl); EtOAc (ethyl acetate); Bn (benzyl); THF (tetrahydrofuran); DMF (dimethylformamide); BOC (tert-butyloxycarbonyl, a protecting group); DMAP (1,1′-dimethylaminopyridine), Ms (methanesulfonyl, mesyl); DIEA (diisopropylethylamine); TFA (trifluoroacetic acid); DIBAL (diisobutylaluminum hydride); PyBroP (Bromo-tris-pyrrolidino-phosphonium hexafluorophosphate); DEAD (Diethyl azodicarboxylate); Ac (acetyl); eq. (equivalent); RP (reverse phase); HPLC (high performance liquid chromatography); TLC (thin layer chromatography). Unless otherwise specified, “water” in the following descriptions means water which is deionized (also known as “demineralized”) or of higher purity, e.g., deionized-distilled or deionized-multiply-distilled water. Preferably all materials will be of at least USP grade.
[0296] The compounds of formula 1, 2 and 3 are most conveniently synthesized by employing procedures analogous to those known in the chemical arts for the production of similar compounds. Exemplary processes for the manufacture of compounds of formula 1 2 and 3 as defined in detail hereinabove are provided as further features of the invention and are illustrated by the following procedures in which the meanings of generic radicals are as previously defined unless otherwise qualified. Examples of methods of preparing compounds of the present invention as described herein are provided by Schemes 1-3 below and the description that follows. In the following Schemes, unless otherwise indicated, substituents R 1 -R 15 , R a -R c , L, X, Z 1 and Z 2 are as defined above.
[0297] The compounds of formulas 1, 2 and 3 are generally prepared by forming amide linkages between the groups A, B and C shown in Table 1 below, wherein in compounds of formula 1, B is B1; in compounds of formula 2, B is B2; and in compounds of formula 3, B is B3; wherein L c is a carboxylic acid or an activated form thereof as described further below, and the amide linkages are formed between the L c group of A and the amino group —NHR 9 , and between the L c group of B and the amine —NHR 5 of C, respectively It will be appreciated by those of skill in the art that there are many well-known methods of forming amide linkages, and that it is generally not important which amide linkage is formed first. Also, it will be appreciated by those of skill in the art that the groups A, B and C are either commercially available or can readily be prepared using materials and methods which are well-known in the art, as well as by the methods and procedures described herein. For example, compounds comprising the group A wherein X is C(R c ) and R 10 is phenyl are commercially available, e.g., 2-biphenylcarboxylic acid, 4′-(methyl)-2-biphenylcarboxylic acid and 4′-(trifluoromethyl)-2-biphenylcarboxylic acid. In addition, numerous pyridyl-phenyl (X is N and R 10 is phenyl) and bipyridyl (X is N and R 10 is pyridyl) compounds are also readily obtained. Compounds of group B are readily formed from commercially available indoles (B1, B2), benzo[b]furans (B3) or benzo[b]thiophenes (B3), as well as by the methods and procedures described herein. Compounds of group C are readily prepared from commercially available phenyl glycines, wherein the carbamoyl moiety C(O)NR 6 R 7 is formed between the carboxylic acid group of the phenylglycine and the amine NR 6 R 7 . Exemplary procedures for forming each of these groups and the amide linkages between them are provided in detail below. The Schemes which follow provide examples of various methods of forming the compounds of formulas 1, 2 and 3 using the synthetic precursors discussed above.
TABLE 1 A B C
[0298]
[0299] Scheme 1 illustrates a method for preparing a compound of formula 1 which comprises reacting a compound of the formula AB1, with an amine of the formula C, or, by reacting a compound of the formula A with an amine of the formula B1C, where L c is a carboxylic acid, preferably, an activated carboxylic acid. In both cases, a compound of formula 1 is prepared by the formation of an amide linkage.
[0300] Activated carboxylic acids of the compound of formula A and AB1 are readily formed by conventional means, for example, wherein -L c is —COOH, by reacting the free acid with a carbodiimide, e.g., 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (“EDC”) or 1,1′-carbonyldiimidazole (“CDI”). EDC, if used, may advantageously be polymer-bound, as disclosed in U.S. Pat. No. 5,416,193. Preferably, the amide linkage reaction is carried out in the presence of a suitable base. An example of a suitable base for use in the coupling reaction is a polymer bound amine, such as polymer bound morpholino-polystyrene. Preferably, the reaction is carried out in the presence of an alcohol e.g., a C 1 -C 4 alcohol such as methanol, ethanol, propanol, isopropanol, n-butanol or t-butanol. Alternatively, the carboxylic acid may be activated by conversion to its corresponding acid chloride by e.g., treatment with oxalyl chloride in methylene chloride in the presence of a catalytic amount of DMF. Compounds A, C, AB1 and B1C, and their synthetic precursors and intermediates are each readily prepared using well-known methods for the formation of amide linkages, and also by the methods disclosed herein.
[0301] Another example of a method for forming the amide linkage between AB1 and C, from the compound AB1 where L c is a carboxylic acid, is by combining AB1, C, and PyBroP (about 1 eq) in methylene chloride, followed by the addition of diisopropylethylamine (2-3 eq) and stirring at room temperature from about 30 minutes to 24 hours. The solvent may be evaporated and the product purified by TLC or flash chromatography using ethyl acetate/hexane as the eluting solvent.
[0302] Still another example of a method for forming the amide linkage between AB1 and C, where L c is a carboxylic acid, is to first combine the acid (AB1) with N,O-dimethyl hydroxylamine hydrochloride salt and PyBroP in methylene chloride followed by addition of diisopropylethylamine and stirring for several hours. The resulting N,O-dimethyl hydroxyamide of the acid is purified by flash chromatography and then treated with DIBAL in THF to yield the corresponding aldehyde (i.e., L c is C(O)H). The AB1 aldehyde is then suspended in methylene chloride with C and acetic acid, and after stirring for about 30 minutes, NaB(OAc) 3 H and chloroform are added and the compound of formula 1 purified from the organic layer, e.g., by flash chromatography using methanol/chloroform.
[0303] The method illustrated in Scheme 1 comprising reacting a compound of the formula A with an amine of the formula B1C is advantageous in the utilization of a library of A groups, i.e., phenyl or pyridyl carboxylic acids as in Scheme 1, or other carboxylic acids. In this case, a compound of formula 1, formula 1b or formula 2 may be formed between a compound of the formula B1C and a A group or other carboxylic acid, by reacting A or the other acid with a mixture comprising B1C, EDC and DMAP in methylene chloride, preferably at room temperature, followed by addition of N,N-dimethylethylenediamine, and subsequent purification of the compound of formula 1.
[0304] Scheme 2 illustrates a method of preparing compounds of formula AB1. In Scheme 2, a compound of formula A is reacted with a 5-amino- or 6-amino-indole of formula B1, wherein L e is a carboxylic acid ester to form the compound AB1-e, followed by hydrolysis of L e to form the compound AB, bearing a carboxylic acid group L c , which as described above may be used in the method of Scheme 1 directly or in the form of an activated acid. The group L e may advantageously be —COOR d , wherein R d is a (C 1 -C 6 ) alkyl group or a substituted variation thereon; preferably R d is methyl or ethyl, more preferably ethyl. Where -L c is e.g., —COCl, i.e., an acid chloride, the reaction between A and B1 may be carried out in methylene chloride and pyridine or, in a preferred embodiment, as described in Example 44. AB1-e may be hydrolysed (or otherwise deprotected) to form AB1 by any conventional means, e.g., by addition of aqueous LiOH to a solution of the compound in THF and methanol, or, in a preferred embodiment, as described in Example 44, wherein the compound AB1 has advantageous filtration properties, for example where L c is —COOH and acidification is performed at elevated temperature, and preferably where L c is —COO − K + crystallizing as a 2.5 mole hydrate.
[0305] Still another embodiment of a process for making a compound of the formula 1 wherein R 10 is of the formula —OR 17 is shown in Scheme 3. In this process, an amide linkage is formed between A′B1 and C, wherein A′ is analogous to the group R 1 except that R 10 is, e.g., acetyl or a thioester as exemplified by a compound such as acetylsalicoylchloride. In this process, a compound of the formula A′B1 is formed analogously to the process shown in Scheme 2, by adding to a mixture comprising about 1 equivalent of B1 (ester form, i.e. having “L e ” at the 2-position) and diisopropylethylamine (2 eq) in methylene chloride, about one equivalent of A′, followed by hydrolysis of the ester group Le of A′B1 to produce a carboxylic acid group L c and (preferably as part of the same step) hydrolysis of the acetyl group of A′ to form an alcohol. The alcohol/acid A′B1 is then reacted with C as described above, in the presence of PyBroP to produce a hydroxy-substituted compound A′B1C whose hydroxyl group may then be converted to OR 17 by reaction with an alcohol R 17 OH.
[0306] Compounds of formula A are well-known, and are readily obtained commercially or prepared from commercially available biphenyl, bipyridyl or phenyl-pyridyl compounds substituted with at least a carboxylic acid group or having at least one substituent susceptible to derivatization to a carboxylic acid group. Examples of suitable groups A and methods for preparing them may be found in, for example, U.S. Pat. No. 6,121,283, which is herein incorporated by reference in its entirety. A particularly preferred group of formula A is 4′-(trifluoromethyl)-2-biphenylcarboxylic acid, which is commercially available; other A groups are commercially available or readily prepared from commercially available analogues by means which are well-known in the art.
[0307] Compounds of formula B1 are readily prepared from well-known or commercially available indoles, e.g., 5-nitro or 6-nitro-indole-2-carboxylic acid ethyl ester (“the indole ester”). To prepare a group B1 wherein R 4 is alkyl or alkoxyalkyl, the indole ester in a suitable solvent, e.g., DMF, may be treated with about one equivalent of sodium hydride, followed by addition of a slight molar excess of alkyl iodide or alkoxyalkyl iodide, e.g., methyl iodide, iodomethyl methyl ether, ethyl iodide, 2-iodopropane, etc., followed by quenching with acid, e.g., HCl, and suitable isolation to yield the alkyl or alkoxyalkyl indole ester. Alternatively the alkylating agent may be an alkyl sulfonate ester, e.g. methyl tosylate, and the base may be a inorganic salt, e.g. potassium carbonate, and the product provided by an appropriate isolation, such as described in Example 44. In yet another embodiment, a group B1 wherein R 4 is akyl or alkoxyalkyl and L c =R 4 , may be prepared by exposing commercially available 5-nitro or 6-nitro-indole-2-carboxylic acid to analogous conditions with adjusted stoichiometry.
[0308] Independently, or after alkylation of the indole ester, a compound B1 wherein R 3 is halogen, i.e., chloro, bromo or iodo, may be prepared by treating the indole ester with a N-halosuccinimide in a suitable solvent, e.g., THF, followed by neutralization and isolation.
[0309] After halogenation and/or alkylation (or alkoxyalkylation) the 5-nitro or 6-nitro group of any of the resulting indole esters (i.e., R 3 is H or halo and R 4 is independently H, alkyl or alkoxyalkyl) may then be reduced, e.g., with hydrazine hydrate and Raney Nickel in a suitable solvent, e.g., methanol to yield the 5-amino- or 6-amino-indole ester. Alternatively, the nitro group may be hydrogenated catalytically over palladium based catalysts, e.g. palladium on carbon. Alternatively, the nitro group may be hydrogenated catalytically over palladium based catalysts. Alternatively, the nitro group may be subjected to catalytic transfer hydrogenation using palladium based catalysts and a non-gasseous hydrogen source, e.g., a salt of an amine with formic acid such as ammonium fomate, followed by an appropriate isolation, such as described in Example 44. The 5-amino- or 6-amino-indole esters B1 may advantageously be isolated as their salts with strong acids, e.g. hydrochloric acid. Alternatively the 5-amino or 6-amino-indole esters may be retained in solution for use directly in the following synthetic step.
[0310] The 5-amino- or 6-amino-indole ester may then be reacted with a compound of formula A as in Scheme 2 to form the compound AB1-e, wherein R 9 is hydrogen. The amide nitrogen of AB1-e, is optionally alkylated, e.g., free radical methylation is used to produce R 9 =methyl, preferably before hydrolysis of the carboxylic acid ester to the corresponding 2-carboxylic acid or activated acid form of the compound of formula B1 used as in Scheme 1.
[0311] Compounds of formula B2 are readily prepared from well-known or commercially available indoles, e.g., 5-nitro or 6-nitro-indole-1-acetic acid. Compounds of formula 2 are then readily prepared by forming amide linkages between A, B2 and C using the processes described above for linking B1 to A (or A′) and C.
[0312] Compounds of formula B3 are also readily prepared from well-known or commercially available indoles, e.g., 5-nitro or 6-nitro-benzofuran-2-carboxylic acid. The acid is first esterified, and then the nitro group is reduced to an amine, both using conventional means as described herein, and the amide linkages between A, B3 and C to form a compound of formula 1b are readily formed using the processes described herein for linking B1 to A (or A′) and C.
[0313] Compounds of formula C are readily prepared by methods analogous to those described above, by forming an amide linkage between a phenyl-glycine amino acid analogue, e.g.,
and an amine of the formula HNR 6 R 7 , wherein R p is H or a protecting group, such as tert-butyloxycarbonyl (“BOC”). Various embodiments of processes for preparing a compound of formula C have been described above, and illustrative examples are provided below.
[0314] One example of a process for preparing a compound of formula C, where, e.g., R 7 is benzyl and R 6 is methyl, involves combining commercially available (S)-N-tert-butoxycarbonyl-2-phenylglycine, 1-hydroxybenzotriazole hydrate and N,N′-dicyclohexylcarbodimide in dichloromethane, and after mixing, adding slowly, with stirring, N-methylbenzylamine in dichloromethane, all at 0-5° C. The resulting slurry is allowed to warm to room temperature overnight before being filtered and the solids washed with dichloromethane. The combined filtrate is preferably subjected to further washes with aqueous weak base and then with aqueous weak acid, and finally washed with water, providing a dichloromethane solution of a phenylglycine acid amide, where the phenylglycine amino group (See Table 1, NHR 5 of C) is t-butoxycarbonyl-protected. After purification, the phenylglycine amide is deprotected, e.g., by addition of concentrated hydrochloric acid, and the monohydrate crystalline form of the product precipitated by the addition of tert-butyl methyl ether and seeding, followed by washing with tert-butyl methyl ether and drying to yield the product C with higher optical purity than its N-protected precursor. The preferred solid form of the product C is characterized by the XRD (X-ray diffraction) data shown in Table 12, as described below.
[0315] Table 12 shows 2-theta values for a simulated X-ray powder diffraction pattern the intermediate compound (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride monohydrate described in Example 44 step (e). The data was simulated using primary data obtained by single crystal X-ray diffraction.
[0316] 2-theta angles and relative intensities were calculated from the single crystal structure using the “Diffraction-Crystal” module [revision no. 99.0102] of Cerius2 [version 4.2 Mat. Sci.]. Pertinent simulation parameters were:
[0000] Wavelength=1.54178 Å
[0000] Polarisation Factor=0.5
[0000] Crystallite Size=500×500×500 Å
[0317] Lorentzian Peak Shape
TABLE 12 2-Theta Intensity Angle (/°) (/%) 5.673 100.00 11.359 8.38 12.848 23.61 13.354 8.19 13.930 8.67 14.091 3.57 15.374 3.21 15.750 3.88 16.668 16.53 17.501 5.36 17.691 6.87 17.790 5.31 18.073 2.47 18.886 2.17 19.361 42.54 19.363 26.18 19.575 3.55 19.633 2.40 19.922 3.34 20.103 15.17 20.216 2.38 21.352 5.08 21.417 6.47 22.022 5.00 22.750 14.75 22.817 6.19 22.832 2.63 23.948 6.50 23.954 5.24 24.322 2.66 24.399 3.20 24.471 5.84 24.681 2.98 24.761 21.22 25.654 9.48 25.699 2.71 25.767 5.84 25.862 2.18 26.425 2.02 26.665 3.22 26.894 2.36 27.054 4.25 27.556 7.66 27.983 2.97 28.071 7.04 28.547 5.53 28.763 3.60 28.771 3.31 29.351 10.87 29.578 5.76 29.983 8.44 30.830 8.48 31.115 9.03 31.746 4.06 31.807 3.79 32.401 2.28 32.540 3.47 33.326 2.08 33.802 2.28 36.240 3.98 37.491 2.71 38.312 2.03 38.360 4.67 39.406 2.45 39.752 3.11 40.510 2.81 43.483 2.17
[0318] In another example of a process for preparing a compound of formula C, where R 6 is methyl and R 7 is benzyl, (RS)-N-tert-butoxycarbonyl-2-phenylglycine, commercially available or prepared from (RS)-2-phenylglycine using methods well known in the art, is combined with 1-hydroxybenzotriazole hydrate, commercially available N-methylbenzylamine and N-[3-(dimethylamino)propyl-N′-ethylcarbodimide hydrochloride in dichloromethane and the resulting mixture stirred for about 24 hours. The resulting mixture is subjected to an aqueous work-up similar to that described above, providing (tert-butyl (RS)-2-[benzyl(methyl)amino]-2-oxo-1-phenylethylcarbamate, which may be treated with trifluorocaetic acid and triethylsilane in dichloromethane, followed by aqueous workup to yield (RS)-N-benzyl-N-methyl-2-phenylglycinamide.
[0319] A salt of the phenylglycine amide may be prepared, e.g., by treating the amide, e.g., ((RS)-N-benzyl-N-methyl-2-phenylglycinamide), with di(o-toluoyl)-L-tartaric acid in a suitable solvent to provide the di(o-toluoyl)-L-tartrate) salt. Tartrate salts of the phenylglycine amides may be broken to provide the amide, which may be purified as its hydrochloride salt.
[0320] In still another embodiment of a process for preparing a compound of formula C, commercially available (RS)-DL-2-phenylglycine is converted to (RS)-4-phenyl-1,3-oxazolidine-2,5-dione using methods well known in the art, which, analogous to the above examples, is then combined with commercially available N-methylbenzylamine. The resulting mixture is then subjected to an aqueous work-up, providing the phenylglycinamide, which may be purified as its hydrochloride salt as described.
[0321] In another embodiment, racemic compounds of the formula C may be resolved via the selective precipitation of one of the enantiomers as its salt with an optically enriched chiral acid, of which many examples are known in the art, from suitable solvents, e.g. methanol and ethanol. Such optically enriched chiral acids may be naturally occuring or synthetic. The precipitated salts may be hydrates or solvates. Breakage of these salts delivers optically enriched free amines of the formula C, which may be purified as-is or as a suitable salts using suitable solvents.
[0322] In a preferred embodiment, (RS)-N-benzyl-N-methyl-2-phenylglycinamide (10.0 g) was treated with di(o-toluoyl)-L-tartaric acid (15.2 g) in methanol (167 mL) at 20° C. The precipitated the salt was filtered and washed with methanol, then dried providing (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate (11.73 g, 46.6%) with 92.7% d.e. (chiral HPLC). This material (1.00 g) was reslurried in hot methanol (8.8 ml) to provide (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate with 99% d.e. (0.79 g, 79% recovery) after filtration, washing and drying. The tartrate salts formed as described maybe broken to provide the free amine of formula C, i.e. (S)-N-benzyl-N-methyl-2-phenylglycinamide, which may be advantageously purified by the formation of a salt with an achiral acid in the presence of appropriate solvents, e.g. precipitation of (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride from mixtures of propan-2-ol and tert-butyl methyl ether as described.
[0323] In another embodiment, a racemic compound of the formula C may be resolved via the selective recrystallization, from a suitable solvent, of its salt with an optically enriched chiral acid, e.g. (RS)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate prepared as described above, to provide diastereomericly enriched salts, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate. Breakage of these salts delivers optically enriched free amines of the formula C, which may be advantageoulsy isolated and used as the hydrochloride salt, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride as described.
[0324] In another embodiment, where optically enriched compunds C are preferrable, the unwanted enantiomer of the compound C may be recycled by racemization. In a more preferred embodiment, the racemization is applied to mother liquors from the resolutions described in the preceding embodiments, by (a) optionally changing the nature of the solvent and (b) refluxing in the presence of a catalytic amount of a carbonyl compound, e.g. 2-chlorobenzaldehyde, thus allowing the isolation of second crops of diastereomericly enriched salts containing the desired enantiomer of compound C, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide di(o-toluoyl)-L-tartrate with 92% d.e. in approximately 50% yield of the solute in the initial ethanolic mother liquors. In an even more preferred embodiment, the catalysed racemization is performed at a suitable temperature and concentration in-situ during the resoluton in a suitable solvent, prior to the isolation of the first crop of product; this “dynamic resolution” allows a first crop yield of product to be significantly greater than the 50% available by traditional salt resolutions. Dynamic resoultions are known in the art, but suitable conditions are generally highly substrate-dependent.
[0325] In still another embodiment of a process for preparing an opticaly enriched compound of formula C, commercially available homochiral (S)-L-2-phenylglycine is converted to (S)-4-phenyl-1,3-oxazolidine-2,5-dione using methods well known in the art, which, may then be combined with commercially available N-methylbenzylamine. The resulting mixture is then subjected to an aqueous work-up, providing the phenylglycinamide, e.g. (S)-N-benzyl-N-methyl-2-phenylglycinamide with 43% e.e. in 49% yield, which may be purified as its hydrochloride salt as described, or di(o-toluoyl)-L-tartrate salt.
Biological Assays
[0326] The selectivity of the apo B secretion/MTP inhibitors was determined by the following protocols.
[0000] Inhibition of Fat Absorption
[0327] Healthy female CF1 mice (Charles River) weighing 18-20 grams upon arrival are employed as test subjects. The mice are housed in groups of 10 in standard caging, and are allowed to acclimate for one week prior to testing. Mice are fasted overnight in a separate procedure room prior to testing. Each treatment group typically consists of 5 mice.
[0328] The test compound is preferably provided as a powder in a glass vial. The dosing solution (0.10 ml/25 g body weight) administered by oral gavage consists of an emulsion of Miglyol 812 (20%), Cremaphor (5%), Water (75%). An appropriate volume of Miglyol is first added to the test compound, and the vial vortexed for approximately 1 minute. Next, the appropriate volume of Cremaphor is added, and the vial again vortexed as previously. The appropriate volume of water is then added, and the emulsion formed by vortexing and briefly sonicating.
[0329] Hamster liquid diet (Bioserve F0739) (dose volume 0.5 ml/25 g body weight) is prepared by adding (for every 10 mL needed) 2.5 grams liquid diet powder, 10 mL water and 5 microcuries glycerol-3H-trioleate (Amersham TRA191) to a laboratory blender. The mixture is then blended at high speed for approximately 1 minute. The liquid diet is stored at 4° C. until use.
[0330] Sample tubes are weighed (Falcon 15 ml polypropylene conical). Three milliliters of 2.5N KOH is then added to each tube.
[0331] Following overnight fasting, each mouse is dosed (see above volumes) with test compound followed immediately by liquid diet. Positive (a known potent MTP inhibitor) and negative control groups (vehicle) are included in each assay. One scintillation vial is sham dosed every 30 mice in order to determine the activity of the initial bolus.
[0332] At two hours post dose the mice are euthanized by carbon dioxide inhalation, the abdominal cavity opened, and the small intestines removed and placed in the KOH conical tube. Each tube is then weighed.
[0333] Tubes containing intestines are then placed in a 75° C. water bath for 1.5-2 hours. Following saponification, the tubes are vortexed and 200 μL saponate placed in a 20 mL liquid scintillation vial. Samples are decolorized (for 30 minutes) by adding 200 μL of 30% (w/w) hydrogen peroxide. Each sample is neutralized by the addition of 200 μL of 3N HCL. Ten milliliters of Ready Safe® (Beckman) liquid scintillation fluid are added and the samples were counted on a Beckman Coulter LS 6500 scintillation system.
[0334] The calculations are carried out as follows:
weight of saponate=weight of tube (KOH+intestine)−weight of empty tube saponate fraction=0.22/saponate weight (density of the saponate=1.1 g/mL; therefore the weight of the aliquot is equal to 0.22 g) total DPM for the entire intestine=DPM of sample/saponate fraction The initial bolus DPM is calculated by averaging the counts from the sham dosed scintillation vials. The fraction of bolus recovered from the intestine (percent recovery)=total DPM/bolus count. Percent recovery from each test group=average of percent recovery from each mouse.
Interpretation of Results:
[0341] To compare efficacy of test compounds, an ED 25 for intestinal fat absorption is calculated. The (average) percent triglyceride recovery (percent unabsorbed and remaining in the intestine) of the vehicle control group is adjusted to equal 0%, and the (average) percent recovery of the compound control group is adjusted to equal 100%. The same calculations are applied to the percent recovery values obtained for test compounds and an adjusted percent recovery is obtained (% recovery of the test sample−% recovery of vehicle control group/(% recovery of positive control group−% recovery of vehicle control group)). An ED 25 is then calculated by plotting a graph of compound concentration vs. adjusted percent recovery.
[0000] Serum Triglyceride Lowering
[0342] Healthy female CF1 mice (Charles River) weighing 18-20 grams upon arrival are employed as test subjects. The mice are housed in groups of 10 in standard caging, and were allowed to acclimate for one week prior to testing. Mice are fasted overnight in a separate procedure room prior to testing. Each treatment group typically consists of 10 mice.
[0343] The test compound is preferably provided as a powder in a glass vial. The dosing solution (0.250 ml/25 g body weight) administered by oral gavage consists of an emulsion of Miglyol 812 (40%), Cremaphor (10%), Water (50%). An appropriate volume of Miglyol is first added to the test compound, and the vial vortexed for approximately 1 minute. Next, the appropriate volume of Cremaphor is added, and the vial again vortexed as previously. The appropriate volume of water is then added and the emulsion formed by vortexing and briefly sonicating.
[0344] Following overnight fasting, each mouse is dosed (see above volumes) with test compound. At 1 hour post dose the mice are euthanized by carbon dioxide inhalation and blood collected for triglyceride quantitation.
[0345] Serum triglyceride values are quantitated using a calorimetric endpoint assay (Wako Triglyceride E kit # 432-4021) on a Spectra Max 250 plate reader with Softmax Pro software. All samples are run in duplicate.
[0346] For comparison of triglyceride values, the percent change from control is calculated. The average triglyceride value of the test compound group is divided by the average triglyceride value of the vehicle group, multiplied by 100 and then subtracted from 100%. The ED 25 value is then calculated by plotting a graph of compound concentration versus percent change from control.
[0347] The relative values of the ED 25 for triglyceride lowering and the ED 25 for inhibition of intestinal fat absorption are used as a means to compare selectivity of the test compounds.
[0348] Where HPLC is referred to in the preparations and examples below, the general conditions used, unless otherwise indicated, are as follows: the column used was a Phenomenex Luna™ C-8 column (3.0×250 mm), and the column was eluted using a gradient of 90% A 10% B to 100% B over 45 minutes, where solvent A was 0.1% formic acid in water and solvent B was acetonitrile. The column was run on a Agilent 1100 MSD system.
EXAMPLES
Example 1
(S)-1-Ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}amide
[0349]
[0350] (a) 1-Ethyl-5-nitro-1H-indole-2-carboxylic acid ethyl ester.
[0351] 5-Nitro-1H-indole-2-carboxylic acid ethyl ester (5 g, 21.3 mol) was dissolved in DMF (50 mL). The reaction mixture was cooled to 0° C. Sodium hydride (1.02, 25.5 mmol, 60% in mineral oil) was added to the above solution in portions over 10 minutes. The mixture was stirred at room temperature for 30 minutes. Ethyl iodide (6.5 g, 42 mmol) was added to the above solution and the reaction mixture was stirred overnight. Ethanol (30 mL) was added to the reaction mixture and the mixture was poured into cold water (800 mL). The crude product was collected by filtration and used directly in next step without further purification (5 g).
[0352] (b) 5-Amino-1-ethyl-1H-indole-2-carboxylic acid ethyl ester.
[0353] The 1-ethyl-5-nitro-1H-indole-2-carboxylic acid ethyl ester (5 g, 19.1 mmol) of step (a) was dissolved in EtOH/n-PrOH (100 mL, 1/1). Palladium hydroxide (1.14 g) and ammonium formate (3.92 g, 62.2 mmol) were added to the above solution. The mixture was heated to reflux for 2 hours. The reaction mixture was cooled to room temperature and the catalyst was filtered off through Celite. The solvent was removed under reduced pressure. The crude product was dissolved in dichloromethane (300 mL) and washed with NaHCO 3 (150 ml×2). The organic layer was collected, dried (Na 2 SO 4 ) and evaporated. The crude product was purified by chromatography to furnish the desired product (4 g, 90%).
[0354] (c) 1-Ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid ethyl ester.
[0355] 4′-Trifluoromethyl-biphenyl-2-carboxylic acid (5.04 g, 18.95 mmol) and 1-ethyl-5-nitro-1H-indole-2-carboxylic acid ethyl ester (4.00 g, 17.23 mmol) were dissolved in DCM (100 mL). DIEA (8 g, 61.8 mmol) was added to the above mixture and the mixture was stirred at room temperature for 5 minutes. PyBroP (9.63 g, 20.67 mmol) was added to the above solution in one portion. The reaction mixture was stirred for another 3 hours. The precipitate was filtered off and washed with cold DCM to provide the title compound (4.5 g, 54.4%).
[0356] (d) 1-Ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid.
[0357] 1-Ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid ethyl ester (4.5 g, 9.37 mmol) was added to MeOH/H 2 O(110 mL, 10/1). Lithium hydroxide monohydrate (1.5 g, 35.7 mmol) was added to the above mixture. The mixture which resulted was heated to reflux overnight. The solvent was removed under reduced pressure and the residue was dissolved in H 2 O (500 mL). The solution was acidified with 6N HCl to pH 2. The solid was collected by filtration and dried under vacuum (4.0 g, 94.5%).
[0358] (e) (S)-(Benzylcarbamoyl-phenyl-methyl)-carbamic acid tert-butyl ester.
[0359] (S)-tert-Butoxycarbonylamino-phenyl-acetic acid (1.009, 4 mmol) was dissolved in DCM (15 mL). Benzylamine (0.428 g, 4 mmol) and DIEA(0.65 g, 5 mmol) were added to the above mixture. The mixture which resulted was stirred at room temperature for a few minutes. PyBroP(2.10 g, 4.5 mmol) was added to the above solution in one portion and the reaction mixture was stirred overnight. The reaction mixture was diluted with DCM (150 mL) and washed with NaHCO 3 (50 mL×2, sat.). The organic layer was collected and dried (Na 2 SO 4 ) and the solvent was removed under reduced pressure. The crude product was purified by chromatography to provide the desired product (0.85 g, 62%).
[0360] (f) (S)-2-Amino-N-benzyl-2-phenyl-acetamide hydrochloride.
[0361] (S)-(Benzylcarbamoyl-phenyl-methyl)-carbamic acid tert-butyl ester (0.85 g, 2.50 mmol) was dissolved in HCl/dioxane(10 mL, 4.0 M). The mixture was stirred at room temperature overnight. The volatiles were removed under reduced pressure to provide the desired product in quantitative yield.
[0362] (g) (S)-1-Ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-(benzylamino)-2-oxo-1-phenylethyl] amide
[0363] 1-Ethyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid (0.05 g, 0.11 mmol) and (S)-2-Amino-N-benzyl-2-phenyl-acetamide hydrochloride (0.031 g, 0.11 mmol) were combined in DCM (3 mL) and DIEA (1.1 mL) was added to the above mixture. PyBroP (0.077 g, 0.17 mmol) was added to the above mixture in one portion. The mixture which was resulted was stirred overnight. The crude mixture was then purified by HPLC to furnish the desired product (52.7 mg). HPLC retention time 16.892 min.; Mol. Wt. (calc) 674.7; MS (found) 675.2.
[0364] Examples 2-24 were prepared similarly to the above example. In each of Examples 2-24, the A group comprised (4′-trifluoromethyl)-biphenyl-2-carbonyl linked to a 5-amino group of B1.
[0365] In Examples 6, 11 and 16, R 6 and R 7 together with the nitrogen atom to which they are attached comprise the listed heterocyclyl group. The benzylation of the indole nitrogen in Example 14 was performed similarly to Example 1, step (a). All of the required amines HNR 6 R 7 are commercially available or readily prepared using methods well-known in the art.
TABLE 2 mol. wt. MS HPLC Example R 4 R 6 R 7 (calc) (found) (min) 2 Methyl H 4-Methoxy-benzyl 690.729 691.2 15.98 3 Propyl Methyl Benzyl 702.783 703.2 20.797 4 Propyl H Butyl 654.739 655.2 18.478 5 propyl Methyl Butyl 668.766 669.2 21.237 6 Propyl Morpholin-4-yl 668.722 669.2 16.102 7 H Ethyl Ethyl 612.658 613.2 15.158 8 Ethyl H Isopropylmethyl 640.712 641.2 17.318 9 Ethyl Methyl Benzyl 688.756 689.2 19.712 10 Ethyl Methyl Propyl 640.712 641.2 18.505 11 Ethyl Pyrrolidin-1-yl 638.696 639.2 16.558 12 H H Propyl 598.63 599.2 13.357 13 H H Cyclopropylmethyl 610.642 611.2 13.741 14 Benzyl H Isopropylmethyl 702.783 703.2 19.25 15 Propyl H Benzyl 688.756 689.2 24.897 16 H Pyrrolidin-1-yl 610.642 611.2 13.337 17 H Methyl Pyridin-3-ylmethyl 661.69 662.2 5.671 18 Methyl Methyl Pyridin-3-ylmethyl 675.717 676.2 7.099 19 Benzyl Methyl Pyridin-3-ylmethyl 751.816 752.2 16.229 20 Ethyl H 3-methyl-benzyl 688.756 689.2 18.511 21 Benzyl H 3-methyl-benzyl 750.828 751.2 20.242 22 Benzyl H 2-phenyl-prop-2-yl 764.855 765.2 21.217 23 Benzyl H 4-methyl-benzyl 750.828 751.2 20.209 24 Methyl H 4-fluoro-benzyl 678.693 679.2 16.585
Example 25
1-Methyl-5-[(6-methyl-4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid (2-methylamino-2-oxo-1-phenylethyl)amide
[0366]
[0367] (a) 6-Methyl-4′-trifluoromethyl-biphenyl-2-carboxylic acid methyl ester was prepared according to methods well-known in the art (see, e.g., WO00/05201).
[0368] (b) 6-Methyl-4′-trifluoromethyl-biphenyl-2-carboxylic acid.
[0369] 6-Methyl-4′-trifluoromethyl-biphenyl-2-carboxylic acid methyl ester (3.5 g, 11.90 mmol) was dissolved in MeOH/H 2 O (60 mL, 5/1). Lithium hydroxide monohydrate (0.75 g, 17.8 mmol) was added to the above solution. The mixture which resulted was heated to reflux overnight. The solvent was removed under reduced pressure and the residue was dissolved in H 2 O (150 mL). The solution was acidified with HCl (6N) to a pH of about 2. The solid was collected by filtration and dried under vacuum (2.5 g, 75%). MS: 280.2. H 1 NMR (DMSO-d 6 ): δ 2.01 (s, 3H), 7.40 (m, 3H), 7.49 (d, 1H, J=7.3 Hz), 7.65 (d, 1H, J=7.3 Hz), 7.75 (d, 2H, 8.3 Hz).
[0370] (c) 1-Methyl-5-[(6-methyl-4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid ethyl ester was prepared similarly to Example1, step (c).
[0371] (d) 1-Methyl-5-[(6-methyl-4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid was prepared similarly to Example 1, step (d).
[0372] (e) 1-Methyl-5-[(6-methyl-4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid (2-methylamino-2-oxo-1-phenylethyl)amide was prepared similarly to Example 1, step (g).
[0373] The compounds in Table 3 were prepared similarly to Example 25. In Examples 28 and 29, R 6 and R 7 together with the nitrogen atom to which they are attached comprise the listed heterocyclyl group.
TABLE 3 HPLC Example R 4 R 6 R 7 Mol. Wt. (calc) MS (min) 26 Methyl Methyl Benzyl 688.756 689.9 19.563 27 Methyl H Cyclopropylmethyl 638.696 639.8 16.245 28 Methyl Morpholin-1-yl 654.695 655.7 14.74 29 Methyl Pyrrolidin-1-yl 638.696 639.4 16.269 30 Methyl H Propyl 626.685 627.8 15.959 31 Methyl Methyl Pyridin-3-ylmethyl 689.744 690.7 7.821 32 Methyl H 4-methoxy-benzyl 704.756 705.9 16.961 33 Methyl H 4-carboxylic acid 732.766 733.9 16.564 methyl ester 34 Methyl H Propen-3-yl 624.6689 625.8 15.356 35 Methyl H Methyl 598.63 599.3 13.269
Example 36
1-Methyl-5-{[2-(4-trifluoromethyl-phenyl)-pyridine-3-carbonyl]-amino}-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}amide
[0374]
[0375] (a) 2-(4-Trifluoromethyl-phenyl)-nicotinic acid methyl ester was prepared according to the literature (WO00/05201).
[0376] (b) 2-(4-Trifluoromethyl-phenyl)-nicotinic acid was prepared similarly to 6-Methyl-4′-trifluoromethyl-biphenyl-2-carboxylic acid as described in Example 25.
[0377] (c) 1-Methyl-5-{[2-(4-trifluoromethyl-phenyl)-pyridine-3-carbonyl]-amino}-1H-indole-2-carboxylic acid ethyl ester was prepared similarly to Example 1, step (c).
[0378] (d) 1-Methyl-5-{[2-(4-trifluoromethyl-phenyl)-pyridine-3-carbonyl]-amino}-1H-indole-2-carboxylic acid was prepared similarly to Example 1, step (d).
[0379] (e) 1-Methyl-5-{[2-(4-trifluoromethyl-phenyl)-pyridine-3-carbonyl]-amino}-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}amide was prepared similarly to Example 1, step (g).
[0380] The compounds in Table 4 were prepared similarly to Example 36. In Examples 40 and 41, R 6 and R 7 together with the nitrogen atom to which they are attached comprise the listed heterocyclyl group.
TABLE 4 Mol. wt. HPLC Example R 4 R 6 R 7 (calc) MS (min) 37 Methyl Ethyl Ethyl 38 Methyl H Cyclopropylmethyl 625.65 626.8 11.50 39 Methyl H Benzyl 661.69 662.8 12.95 40 Methyl Morpholin-4-yl 641.65 642.5 9.72 41 Methyl Pyrrolidin-1-yl 625.65 626.5 11.44 42 Methyl Methyl Pyridin-3-yl 676.70 677.5 3.72 43 Methyl H 4-carboxylic acid methyl ester 719.73 720.8 12.10
Example 44
[0381] Where HPLC is referred to in steps (c), (d), (e), and (f) of this example below, unless otherwise stated, the conditions used are as follows: the column used was a Jones Genesis C-18 300 4 μ column (150 mm, part No. FM15960E), and the column was eluted using a gradient of 95% A 5% B to 10% A 90% B over 12 minutes, where solvent A was 0.1% trifluorocaetic acid in water and solvent B was 0.1% trifluorocaetic acid in acetonitrile, with a flow rate of 1.5 ml/min. The column was run on a Hewlett Packard 1100 system. (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′biphenyl]-2-carboxamido]-1H-indole-2-carboxamide
[0382] (a) Ethyl 1-methyl-5-nitro-1H-indole-2-carboxylate was prepared by methylation of ethyl 5-nitro-1H-indole-2-carboxylate using methods well known in the art (see, e.g., E.F.V. Scriven et al., J.C.S., P.T.1, (1979) p. 53-59). For example, methylation may be achieved using any compatible combination of electrophilic methylating agent, i.e., H 3 C-LG, where LG is a leaving group, and a base, e.g., using dimethylsulfate, methyl iodide (Example 45, step (a)) or methyl tosylate, with bases such as sodium hydride, potassium t-butoxide or potassium carbonate. Preferably, methyl tosylate and potassium carbonate are used as follows:
[0383] To a refluxing mixture of commercially available ethyl 5-nitro-1H-indole-2-carboxylate (420 g) and potassium carbonate (272.6 g) in acetonitrile (3360 mL) was added a solution of methyl p-toluenesulfonate (367.3 g) in acetonitrile (630 mL), and the resulting mixture refluxed for 18 hours. The mixture was then cooled to 20° C. over 3 hours and water (4200 mL) added over a 3 hour period. The product was granulated, filtered, washed with a 50/50 mixture of demineralized water and acetonitrile (630 mL), demineralized water (420 mL) and then with ethanol (420 mL), and dried, yielding the product ethyl 1-methyl-5-nitro-1H-indole-2-carboxylate (436.1 g, 96%).
[0384] (b) Ethyl 5-amino-1-methyl-1H-indole-2-carboxylate.
[0385] Alternative A. To a mixture of ethyl 1-methyl-5-nitro-1H-indole-2-carboxylate (420 g), from step (a) or commercial sources, and 10% palladium on carbon catalyst (50% wet) (42 g) in ethanol (4200 mL) was added a solution of ammonium formate (541.5 g) in demineralized water (840 mL) at between 25-35° C. over 3 hours. The mixture was stirred for 18 hours at 20° C., and then filtered, washing the solids with ethanol (2100 mL). The combined filtrate and washings were concentrated to 840 mL under vacuum at about 20° C. The resulting slurry was granulated at 5° C., filtered, washed with chilled ethanol (420 mL), and dried to give product ethyl 5-amino-1-methyl-1H-indole-2-carboxylate (316.5 g, 86%).
[0386] Preferred alternative B. A mixture of ethyl 1-methyl-5-nitro-1H-indole-2-carboxylate (150.0 g), from step (a) or commercial sources, and 10% palladium on carbon catalyst (50% wet) (15.0 g) in ethyl acetate (1800 mL) was hydrogenated at 3 bar at 30° C. for 8 hours. The mixture was then filtered and the solids washed with ethyl acetate (300 mL). The combined filtrate and washings were partially azeotropically dried at reflux and then concentrated to 800 mL to give a solution of product ethyl 5-amino-1-methyl-1H-indole-2-carboxylate in ethyl acetate.
[0387] The acid salts of ethyl 5-amino-1-methyl-1H-indole-2-carboxylate are also readily available via methods well-known in the art. For example, the hydrochloride salt is readily prepared by treating an ethylacetate solution of the amine with hydrochloric acid in propan-2-ol.
[0388] (c) Ethyl 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylate
[0389] Alternative A. 4′-(Trifluoromethyl)[1,1′-biphenyl]-2-carboxylic acid (133 g), commercially available, thionyl chloride (89 g) and a catalytic amount of N,N-dimethylbenzamide (2.3 g) were combined in toluene (665 mL) at 55-60° C. over 2 hours, and the mixture heated at 80° C. for 1 hour. The excess reagent was removed by atmospheric co-distillation with toluene (600 ml distillate removed), providing a solution of 4′-(trifluoromethyl)[1,1′-biphenyl]-2-carbonyl chloride, which was combined with ethyl 5-amino-1-methyl-1H-indole-2-carboxylate (109 g) from the previous step, ethyl acetate (4660 ml) and N,N-diisopropylethylamine (131 mL) at 18-29° C. The resulting slurry was cooled, filtered and the crude product solids were washed with propan-2-ol (330 mL). The crude product was twice reslurried in a 70/30 mixture of demineralized water and propan-2-ol (2×1500 mL), and the solids were filtered, washed with propan-2-ol (400 mL) and dried, yielding the title compound, ethyl 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylate (167 g, 71.8%).
[0390] Preferred alternative B. A solution of commercially available 4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxylic acid (150.0 g) in toluene (975 ml) and acetonitrile (1275 mL) was added to a solution of thionyl chloride (100.4 g) and N-methylpyrrolidone (3.7 g) in toluene (750 mL) at reflux. The resulting mixture was heated at reflux for 18 hrs, then the acetonitrile and excess thionyl chloride were distilled off by reducing the volume to 900 mL. Additional toluene (2250 mL) was then added before re-concentrating to provide a solution of the intermediate acid chloride (4′-(trifluoromethyl)[1,1′-biphenyl]-2-carbonyl chloride) (900 mL). This solution was then diluted with ethyl acetate (2620 mL) and N,N-diisopropylethylamine (109.5 g) was added. An ethyl acetate solution of ethyl 5-amino-1-methyl-1H-indole-2-carboxylate (1.07 mole equivalents), from step (b), (solution volume 800 mL) was then added in two portions at 20-25° C., seeding with product (ethyl 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylate) between portions. The crude product was granulated overnight then isolated by filtration and washed with propan-2-ol (450 mL). The crude product was twice reslurried in a 75/25 mixture of demineralized water and propan-2-ol (2×180 mL), and the solids were filtered, washed with propan-2-ol (450 mL) and dried, yielding product (ethyl 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylate) (196 g, 74.5%). Mol wt (calc) 466.46, MS: 467.1 (MH + ). 1 H NMR (DMSO-d 6 ): δ 1.31 (t, 3H, J=7.2 Hz), 3.97 (s, 3H), 4.30 (q, 2H, J=7.2 Hz), 7.12 (s, 1H), 7.34 (d, 1H), 7.46-7.74 (complex, 9H), 7.93 (s, 1H), 10.22 (s, 1H). HPLC retention time 11.10 minutes.
[0391] (d) Alternative A. 1-Methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid sodium salt hydrate.
[0392] Ethyl 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylate (46.7 g) from the previous step and aqueous sodium hydroxide (8.0 g in 140 ml) were combined in refluxing ethanol (280 mL) for 1 hour. The solution was cooled, granulating overnight and the resulting slurry was filtered. The product solids were washed with an ethanol-water mixture and dried, yielding the title compound, 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid sodium salt hydrate (36.3 g, 79% as-is). Anhydrous Mol wt of parent acid (calc) 438.41, MS: 439.2 (MH + ), 437.0 (M − ). 1 H NMR (DMSO-d 6 ): δ 4.00 (s, 3H), 6.55 (s, 1H), 7.12-7.75 (complex, 11H), 10.04 (s, 1H). HPLC retention time 9.30 minutes.
[0393] Alternative B. 1-Methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid hemihydrate.
[0394] 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid sodium salt hydrate (0.62 g), from the previous alternative, and aqueous hydrochloric acid (2 molar) were combined in refluxing ethanol (13 mL) and water (1.3 mL). The mixture was cooled, granulating overnight, chilled in ice and the resulting slurry was filtered. The product solids were dried, yielding the title compound, 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid hydrate (0.5 g, 83%, containing 2% water by weight). Anhydrous Mol wt (calc) 438.41, MS: 439.35 (MH + ), 437.20 (M − ). 1 H NMR (DMSO-d 6 ): δ 3.97 (s, 3H), 7.13 (s, 1H), 7.30-7.75 (complex, 10H), 7.92 (s, 1H), 10.21 (s, 1H). HPLC retention time 9.29 minutes.
[0395] Preferred alternative C. 1-Methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid potassium salt 2.6 hydrate.
[0396] A solution of potassium hydroxide (54.1 g) in water (600 mL) was added over 15 minutes to a suspension of ethyl 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylate (300 g), from the previous step, in propan-2-ol (4500 mL) at 60° C. and the resulting mixture was heated to reflux for an hour. The solution was seeded with product (1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid potassium salt) and the mixture granulated at 60-70° C. for two hours. The mixture was slowly cooled to 0-5° C. and the product potassium salt collected by filtration, washing with a chilled 90/10 mixture of propan-2-ol and demineralized water (510 mL total volume). The product solids were dried, yielding 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid potassium salt 2.6 hydrate (287.4 g, 85% correcting for water content of 9.1% by weight). Anhydrous Mol wt of parent acid (calc) 438.41, MS: 439.3 (MH + ), 437.3 (M − ). 1 H NMR (DMSO-d 6 ): δ 3.99 (s, 3H), 6.53 (s, 1H), 7.12-7.76 (complex, 11H), 10.05 (broad), HPLC retention time 9.30 minutes. The preferred solid form of the product is characterized by the pXRD (powder X-ray diffraction) pattern shown in FIG. 7 .
[0397] (e) (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride monohydrate
[0398] (S)-N-tert-butoxycarbonyl-2-phenylglycine (250 g) and 1-hydroxybenzotriazole hydrate (136.2 g) and N,N′-dicyclohexylcarbodimide (205.1 g) were combined in dichloromethane (3000 mL) at 0-5° C. and the mixture stirred for 15 minutes. A solution of N-methylbenzylamine (128.1 mL) in dichloromethane (835 mL) was added slowly, maintaining 0-5° C. The resulting slurry was allowed to warm to room temperature overnight before being filtered, washing the by-product solids with dichloromethane (500 mL). The combined filtrate was twice washed with saturated aqueous sodium hydrogen carbonate (2×1500 mL), twice washed with 50% saturated aqueous sodium hydrogen carbonate solution (2×1500 mL), once washed with 2.5% aqueous citric acid solution (1500 mL) and once washed with demineralized water (1500 mL), providing a dichloromethane solution of tert-butyl (S)-2-[benzyl(methyl)amino]-2-oxo-1-phenylethylcarbamate. Analysis by chiral HPLC showed that 2% of the wrong enantiomer (tert-butyl (R)-2-[benzyl(methyl)amino]-2-oxo-1-phenylethylcarbamate) to be present at this stage.
[0399] The solvent was replaced with propan-2-ol (2400 mL) via distillation at 20-25° C. and the solution cooled to and maintained at 0-5° C. during the addition of concentrated hydrochloric acid (1000 mL). The resulting solution was allowed to warm to room temperature overnight before the excess reagent byproducts and water were removed by co-distillation with additional propan-2-ol (8000 mL), providing a concentrated solution of product at 50-60° C. The product was precipitated by the addition of tert-butyl methyl ether (1875 mL) maintaining 50-60° C. and seeding. The resulting slurry was cooled to 20° C., and the solids were filtered, washed with tert-butyl methyl ether (500 mL) and dried, yielding product (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride monohydrate (190.8 g, 62% corrected for water content of 6.35% by weight). Analysis by chiral CE showed that 0.2% of the wrong enantiomer ((R)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride monohydrate) to be present at this stage. Anhydrous Mol wt of parent amine (calc) 254.33, MS: 255.4 (MH + ). 1 H NMR (DMSO-d 6 ): major/minor rotomers δ 3.298 (s, 3H), 4.46/4.55 (m=2×dd, 2H), 5.55/5.57 (2×s, 1H), 6.93-7.57(complex, 10H), 8.70 (s broad, 3H), HPLC retention time 5.87 minutes.
[0400] The preferred solid form of the product is characterized by the XRD (X-ray diffraction) data shown in FIG. 6 .
[0401] (f) (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide
[0402] 1-Methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid sodium salt (16.0 g), from step (d) alternative A, methanesulfonic acid (2.24 mL), 1-hydroxybenzotriazole hydrate (5.32 g) and N-[3-(dimethylamino)propyl-N′-ethylcarbodimide hydrochloride (8.66 g) were combined in dichloromethane (384 mL) at 0-5° C. and the mixture stirred for 1 hour. Triethylamine (4.78 ml mL) was added followed by a slurry of (S)-N-benzyl-N-methyl -2-phenylglycinamide hydrochloride (11.1 g), from step (e), in dichloromethane (48 mL) was added slowly, maintaining 0-5° C. The resulting slurry was allowed to warm to room temperature overnight. Further triethylamine (2.4 mL) was added at 0° C. After approximately 2 hours, the mixture was twice washed with saturated aqueous sodium hydrogen carbonate (2×200 mL), once washed with 0.5 M aqueous hydrochloric acid solution (200 mL) and once washed with demineralized water (200 mL) adjusting to pH=6 with aqueous sodium hydrogen carbonate solution, providing a dichloromethane solution of (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide.
[0403] Using the dichloromethane solution of the title compound, the solvent was replaced with propan-2-ol (32 mL) via distillation, the warm solution was diluted with tertbutyl methyl ether (170 mL), cooled and seeded. The product was collected in three initial crops (77%). These were combined with their mother liquors in dichloromethane (75 mL) to provide a solution. The solvent was again replaced with propan-2-ol (32 mL) via distillation, the warm solution was diluted with tertbutyl methyl ether (160 mL), cooled to room temperature, concentrated to half volume, and granulated overnight. The resulting slurry was filtered and the cake washed with a 1:1 mixture of propan-2-ol and tert-butyl methyl ether and dried in vacuum, yielding product (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide in Form A (16.3 g, 69.5%). MS: 675.1 (MH + ). 1 H NMR (DMSO-d 6 ): major/minor rotomers δ 2.89/2.78 (s, 3H), 3.94/3.90 (s, 3H), 4.57 (m=2×dd, 2H), 6.07/6.13 (d, 1H, J=7.4/7.4 Hz), 7.11-7.76 (complex, 21H), 7.86 (s, 1H), 8.79/8.84 (d, 1H, J=7.4/7.7 Hz), 10.20 (s, 1H). Mol wt (calc) 674.73; MS 675.2. HPLC retention time 17.948 minutes using the standard conditions cited before Example 1.
[0404] The preferred solid form of the product, Form A, is characterized by the pXRD (powder X-ray diffraction) pattern shown in FIG. 1 and DSC (differential scanning calorimetry) trace shown in FIG. 2 .
[0405] Alternatively and preferably, the title compound is prepared as follows: A solution of methanesulfonic acid (34.0 g) in dichloromethane (85 mL) was added to a mixture of 1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxylic acid potassium salt hydrate (170 g), from step (d) alternative C, and 1-hydroxybenzotriazole hydrate (54.6 g) in dichloromethane (3400 mL) at 0° C. N-[3-(dimethylamino)propyl-N-ethylcarbodimide hydrochloride (88.4 g) in dichloromethane (680 mL) was then added over 30 minutes and the resulting mixture stirred at 0° C. for 1 hour. Triethylamine (53.9 g) in dichloromethane (170 mL) was then added over 10 minutes followed by a solution of (S)-N-benzyl-N-methyl-2-phenylglycinamide hydrochloride hydrate (120.6 g), from step (e), in dichloromethane (680 mL) and the resulting mixture stirred at 0° C. for 30 minutes before allowing to warm to 20° C. for 16 hours. The mixture was twice washed with saturated aqueous sodium hydrogen carbonate (2×2040 mL), once washed with 0.25 M aqueous hydrochloric acid solution (2040 mL) and once washed with demineralized water (2040 mL). The resulting product solution was concentrated to 595 mL under reduced pressure and the concentrate combined with an acidic ion-exchange resin (240 g) in propan-2-ol (595 mL). The mixture was stirred for 2 hours before filtering, washing the solids with a 50/50 mixture of propan-2-ol and dichloromethane (170 mL) and concentrating to a volume of 595 mL. The solution was diluted with propan-2-ol (510 mL) and then re-concentrated to a volume of 595 mL before diluting with tert-butyl methyl ether (1700 mL). The resulting solution was cooled to 20° C. and seeded and the mixture stirred for 18 hours before concentrating to a volume of 920 mL under reduced pressure. After further granulation at 20° C. for an additional 48 hours the slurry was filtered and washed with cold propan-2-ol (340 mL). The product solids were dried, yielding the product (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide in Form A (192 g, 80%). HPLC retention time 11.50 minutes using the conditions specific to this example (noted above).
[0406] Alternative solid Form B of the title compound is prepared as follows: The title compound (150.7 g), prepared by any of the methods described, was dissolved in acetonitrile (350 mL) and filtered. Further title compound (30.8 g) was then added as a seed and the resulting mixture diluted with diisopropyl ether (3300 mL) and granulated at 20-25° C. for 48 hours. The solids were filtered, washed with diisopropyl ether and dried to give the product in Form B (163.5 g, 90%). Form B, is characterized by the pXRD (powder X-ray diffraction) pattern shown in FIG. 3 .
[0407] Alternative solid Form G of the title compound is prepared as follows: The title compound (13.5 g), prepared by any of the methods described, was dissolved in ethanol (100 mL) at elevated temperature and the resulting solution allowed to cool and granulate at 20-25° C. for 48 hours. Further ethanol (150 mL) was then added and the resulting mixture granulated at 20-25° C. for a further 48 hours. A portion of this mixture was filtered and the solids were washed with ethanol before separating into two portions. One portion of solid was dried at ambient temperature and pressure to give the product in Form G (1.1 g). Form G, is characterized by the pXRD (powder X-ray diffraction) pattern shown in FIG. 4 .
[0408] Alternative solid Form F of the title compound is prepared as follows: The title compound (13.5 g), prepared by any of the methods described, was dissolved in ethanol (100 mL) at elevated temperature and the resulting solution allowed to cool and granulate at 20-25° C. for 48 hours. Further ethanol (150 mL) was then added and the resulting mixture granulated at 20-25° C. for a further 48 hours. A portion of this mixture was filtered and the solids were washed with ethanol before separating into two portions. One portion of solid was dried under vacuum at 50° C. to give the product in Form F (1.2 g). Form F, is characterized by the pXRD (powder X-ray diffraction) pattern shown in FIG. 5 .
[0409] Alternative solid Form F of the title compound may also be prepared as follows: The title compound in Form G (1.214 g), prepared by any of the methods described, was dried under vacuum at 50° C. to give the product in Form F (1.195 g). Form F, is characterized by the pXRD (powder X-ray diffraction) pattern shown in FIG. 5 .
Example 45
[0410] Compounds of formula 1 where R 3 is halogen, preferably chloro, were prepared in the following manner:
[0411] (a) 1N-methyl-5-nitroindole-2-carboxylic acid ethyl ester.
[0412] To a solution of 5-nitroindole-2-carboxylic acid ethyl ester (30.45 g, 130 mmol) in DMF (200 mL) was added 60% NaH (6.4 g, 160 mmol) in several portions, and the mixture was stirred under nitrogen at room temperature for 30 minutes. To this was then slowly added methyl iodide (15.56 mL, 250 mmol), and the stirring was continued for 2 hours. The reaction mixture was quenched with 0.5 N HCl solution (400 mL) and extracted with 2:1 EtOAc/benzene solution (600 mL. The organic layer was washed with water (500 mL), brine (500 mL), dried over MgSO 4 , and then concentrated in vacuo to give 26.7 g of the title compound.
[0413] (b) 3-Chloro-1N-methyl-5-nitroindole-2-carboxylic acid ethyl ester.
[0414] The product of step (a) (24.8 g, 100 mmol) was dissolved in THF (500 mL), followed by the addition of N-chlorosuccinimide (20 g, 150 mmol), and the reaction mixture was stirred at room temperature under nitrogen for 60 hours. The reaction solution was concentrated in vacuo, and the residue was taken into EtOAc (750 mL). The organic layer was washed with 0.5 N NaOH solution (4×750 mL), brine (750 mL), dried (MgSO 4 ), and concentrated in vacuo to afford the crude product which was purified by recrystallization from ethanol to give 13 g of the title compound
[0415] (c) 3-Chloro-1N-methyl-5-amino-indole-2-carboxylic acid ethyl ester.
[0416] To a refluxing mixture of hydrazine hydrate (10.8 ml, 222 mmol) and Raney Ni (6 g) in MeOH (200 mL) was slowly added the product of step (b) (12.6 g), and the refluxing was continued for 6 hours. After cooling to room temperature, the Raney Ni was removed by filtration through Celite, and the solvent was removed in vacuo to give the crude product. The residue was dissolved in toluene (100 mL), and concentrated in vacuo. The residue was again dissolved in toluene (100 mL), and concentrated in vacuo, the residue was suspended in diethyl ether, and the product was collected by filtration to afford 11.3 g of the title compound.
[0417] (d) 3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid ethyl ester
[0418] 4′-Trifluoromethyl-2-biphenylcarboxylic acid was converted to the corresponding acid chloride by treatment with oxalyl chloride in methylene chloride in the presence of catalytic amount of DMF. To a solution of the acid chloride (10.8 g, 38 mmol) and pyridine (3.27 mL, 40 mmol) in methylene chloride (200 mL) was added the product of step (c) (10.1 g, 40 mmol), and the reaction mixture was stirred at room temperature for 1 hour. The reaction solution was diluted to 600 mL with CH 2 Cl 2 , washed with 0.1N HCl solution (2×500 mL) and with brine (500 mL), and then dried (MgSO 4 ). The solvent was evaporated in vacuo to give the crude product which was purified by recrystallization from EtOAc/isooctane to afford 13.8 g of the title compound.
[0419] (e) 3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid
[0420] The product of step (d) may be hydrolyzed as follows: the compound (5.51 g) was dissolved in THF (120 mL) and methanol (40 mL). Under stirring conditions was added LiOH (1.32 g) in water (40 mL). The reaction mixture was stirred at room temperature overnight. To the reaction mixture was then added 1N HCl solution (60 mL), and the aqueous layer was extracted with EtOAc (250 mL). The organic layer was washed with brine (200 mL), and dried (MgSO 4 ). The solvent was evaporated in vacuo to give the crude product which was purified by recrystallization from 1:1 EtOAc/ether to afford 4.4 g of the title compound.
[0421] (f) 3-Chloro-1-methyl-5-[methyl-(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid
[0422] As an alternative to step (e), the product of step (d), in which R 9 is hydrogen, optionally may be alkylated by processes well known in the art. For example, to prepare a compound in which R 9 =methyl, the product of step (d) is treated with Me 2 SO 4 in the presence of KOH, K 2 CO 3 and Bu 4 NHSO 4 in a suitable solvent such as toluene, with heating to 70° C. with stirring for about 30 minutes. After cooling to room temperature, the reaction mixture is diluted with 1N HCl and stirred for 10 min. EtOAc (100 mL) is then added, and the organic layer washed with brine, dried (MgSO 4 ), and solvent removed in vacuo to give the product wherein R 9 is methyl, with appropriate purification e.g., by recrystallization from 1:2 EtOAc/isooctane.
[0423] The resulting indole ester may then be hydrolysed as in step (e), e.g., as follows: the compound is dissolved in 3:1 THF:methanol, LiOH in water is added under stirring conditions and the reaction mixture is stirred at room temperature overnight. To the reaction mixture is then added 1N HCl solution, and the aqueous layer s extracted with EtOAc (about 2 volumes). The organic layer is washed with brine, and dried (MgSO 4 ). The solvent is evaporated in vacuo to give the crude product which may be purified by recrystallization from 1:1 EtOAc/ether to afford an indole carboxylic acid of formula AB1.
[0424] The products of steps (e) and (f), i.e., compounds of formula AB1, may be amide linked to compounds of formula C by methods which are well known in the art, an example of which is described below in step (g)
[0425] (g) 3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-(isopropylamino)-2-oxo-1-phenylethyl]amide
[0426] The product from step (e) (292.5 mg, 0.619 mmol), (S)-N-isopropyl-2-phenylglycinamide hydrochloride salt (182.1 mg, 0.797 mmol), PyBroP (415.8 mg, 0.865 mmol) were suspended in anhydrous CH 2 Cl 2 (6 ml), followed by the addition of DIEA (0.36 ml, 2.07 mol). The reaction mixture was stirred at room temperature for 3.5 h. The product was purified by flash chromatography using 30:70 of hexane:EtOAc to afford 345.5 mg of the title compound.
[0427] Examples 46-65 were prepared similarly to Example 45 above, and Examples 65b-f were prepared similarly to Example 65a below.
TABLE 5 Mol wt. MS HPLC Example R 4 R 5 R 6 R 7 R 9 R 13 (calc) (found) (min) 46 Methyl H Methyl Benzyl H Trifluoromethyl 709.17 709.2 20.185 47 Methyl H H Propyn-3-yl H Trifluoromethyl 643.07 643.2 15.244 48 Methyl H H Isopropyl H Trifluoromethyl 647.10 647.2 16.567 49 Methyl H Methyl Pyrid-3-yl H Trifluoromethyl 710.16 710.2 8.513 50 Methyl H H Propyl H Trifluoromethyl 647.10 647.2 16.67 51 Methyl H Ethyl Benzyl H Trifluoromethyl 723.20 723.2 21.392 52 Methyl H Methyl 3-chloro- H Trifluoromethyl 743.61 744.2 20.578 benzyl 53 Methyl H Methyl Benzyl Methyl Trifluoromethyl 723.20 723.2 21.202 54 Methyl H H Ethyl Methyl Trifluoromethyl 647.10 647.2 15.615 55 Methyl H H Isopropyl Methyl Trifluoromethyl 661.1 661.2 17.161 56 Methyl H Methyl Pyrid-3-yl Methyl Trifluoromethyl 724.18 724.2 9.154 57 H H Methyl Benzyl H Trifluoromethyl 695.14 695.2 19.131 58 Ethyl H Methyl Benzyl H Trifluoromethyl 723.20 723.2 21.172 59 Ethyl H H 4-methoxy- H Trifluoromethyl 739.20 739.2 18.345 benzyl 60 Methyl Methyl Methyl Benzyl H Trifluoromethyl 709.22 709.2 8.966 61 Methoxy- H Methyl Benzyl H Trifluoromethyl 739.20 739.2 19.677 methyl 62 Methyl H H Propyl H H 579.10 579.2 14.388 63 Methyl H H Isopropyl H H 579.10 579.2 14.327 64 Methyl H Methyl Pyrid-2-yl H H 642.16 642.2 11.303 65 Methyl H Methyl Pyrid-3-yl H H 642.16 642.2 6.322 65b Methyl H Methyl Ethyl H Trifluoromethyl 633.12 633.2 4.318 65c Methyl H H 4-methyl- H Trifluoromethyl 695.19 695.2 11.147 benzyl 65d Methyl H H Propyl H Trifluoromethyl 633.12 633.2 6.923 65e Methyl H Ethyl Ethyl H Trifluoromethyl 647.15 647.2 5.071 65f Methyl H H Methyl H Trifluoromethyl 605.06 605.2 5.433
Example 65a
3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-(ethylamino)-2-oxo-1-phenylethyl]amide
[0428]
[0429] (a) 3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid (3.41 g, 6.6 mmol), N,O-dimethyl hydroxylamine hydrochloride salt (0.938 g, 9.4 mmol) PyBroP (4.50 g, 9.4 mmol) were suspended in CH 2 Cl 2 (60 ml), followed by the addition of diisopropylethyl amine, and the resultant reaction mixture was stirred at room temperature for several hours. The reaction solution was concentrated to ˜25 ml, and then directly applied to flash chromatography using 30:70 of EtOAc/hexane to give 2.86 g of the title compound.
[0430] (b) 4′-Trifluoromethyl-biphenyl-2-carboxylic acid (3-chloro-2-formyl-1-methyl-1H-indol-5-yl)-amide:
[0431] To a solution of the product from step (a) (1.56 g, 3.02 mmol) in THF (25 ml) at −78° C. was added DIBAL in THF (1.0 M, 12 ml), and the reaction mixture was stirred at −78 c o for 6 h. The reaction mixture was diluted with NaHSO 4 (0.25 M, 86 ml) and EtOAc (115 ml), and the aqueous layer was extracted with EtOAc (2×100 ml). The combined organic layers were dried (MgSO 4 ) and concentrated in vacuo to about 30 ml in volume. The product was purified by flash chromatography using 1:1 EtOAc/hexane to afford 0.706 g of the title compound.
[0432] (c) 3-Chloro-1-methyl-5-[(4′-trifluoromethyl-biphenyl-2-carbonyl)-amino]-1H-indole-2-carboxylic acid [2-(ethylamino)-2-oxo-1-phenylethyl]amide
[0433] The product from step (b) (407.5 mg, 0.892 mmol), (S)-N-ethyl-2-phenylglycinamide hydrochloride salt (316.3 mg, 1.47 mmol) and acetic acid (10 drops) were suspended in CH 2 Cl 2 (25 mL), and the reaction mixture was stirred at room temperature for 20 min. NaB(OAc) 3 H (2.1 eq) was then added, and the reaction mixture was stirred at 50° C. for 5.5 h. Saturated NaHCO 3 (8 mL) and CHCl 3 (12 mL) were then added, and the organic layer was washed with water (6 mL), and then concentrated in vacuo. The product was purified by flash chromatography using 30:70 of hexane:EtOAc to afford 441.4 mg of the title compound.
Examples 66-85
[0434] Using a compound of formula B1C, substituted biphenyl “A” groups were amide linked to form the compounds shown in Table 6 according to the following method:
[0435] A stock solution containing compound B1C (20.4 mg, 0.0478 mmol), EDC (19.6 mg, 0.0102 mmol), and DMAP (2.47 mg, 0.020 mmol) in CH 2 Cl 2 (0.8 ml) was added to a 1.8 mL reaction vial containing the acid (1.2 eq), and the resulting mixture was shaken at room temperature overnight. To the reaction mixture was then added 0.5 ml of N,N-dimethylethylenediamine and the reaction mixture was then shaken for 18 h. The product was purified by silica gel chromatography using CH 2 Cl 2 /EtOAc. The yields ranged from about 70% to about 95%.
TABLE 6 Example R 13 Other R 13 (if present) Mol. wt. 66 3′-fluoro 5′-fluoro 642.712 67 2′-fluoro 4′-fluoro 642.712 68 3′-trifluoromethyl 5′-trifluoromethyl 742.728 69 4′-chloro — 641.176 70 3′-methyl — 620.758 71 3′-carboxylic acid — 650.741 72 3′-chloro 4′-fluoro 659.166 73 4′-methoxy — 652.822 74 3′-amino — 621.746 75 3′-methoxy — 636.757 76 3′-carboxymethyl — 648.768 77 3′carbamoylmethyl — 663.783 78 4′-ethenyl — 632.769 79 2′-methoxy 4′-methoxy 666.7841 80 4′-hydroxymethyl — 636.757 81 2′-methoxy 5′-chloro 671.202 82 4′-cyano — 631.741 83 4-tert-butyl — 662.839 84 3′-methoxy 4′-methoxy 666.7841 85 3′-fluoro 4′-fluoro 642.712
Example 86
(S)-5-(2-Butoxy-benzoylamino)-1-methyl-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-amide
[0436] (a) 5-(2-Acetoxy-benzoylamino)-1-methyl-1H-indole-2-carboxylic acid ethyl ester
[0437] To a solution of 5-amino-1-methyl-indole-2-carboxylic acid ethyl ester (12.86 g, 58.92 mM) and diisopropylethylamine (20.5 mL, 117.84 mM) in CH 2 Cl 2 at 0° C. was added a solution of acetyl salicyloyl chloride in CH 2 Cl 2 over 30 minutes. After the addition was complete the cooling bath was removed and the mixture was allowed to warm to room temperature and stirred at that temperature for 2 hours. The mixture was transferred to a separatory funnel and the solution was washed with 1N HCl (150 mL) and aqueous NaHCO 3 . The organic fraction was dried over MgSO 4 and filtered. The solvent was removed under reduced pressure to provide the title compound.
[0438] (b) 5-(2-Hydroxy-benzoylamino)-1-methyl-1H-indole-2-carboxylic acid
[0439] The product of step (a) (2.0 g, 5.26 mM) was dissolved in THF (30 mL), methanol (10 mL), and water (10 mL). The mixture was treated with lithium hydroxide (882 mg, 21.04 mM) and the mixture was stirred at room temperature for 3 hours. The mixture was concentrated to 15 mL and the pH was adjusted to about 3.0 with 1N HCl. The mixture was extracted 3 times with ethyl acetate (25 mL). The ethyl acetate fractions were combined, dried over MgSO 4 , filtered and concentrated to provide the title compound.
[0440] (c) (S)-5-(2-Hydroxy-benzoylamino)-1-methyl-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-amide
[0441] The product of step (b) (1.36 g, 4.38 mM), PyBrOP (2.45 g, 5.26 mM), and (S)-N-benzyl-N-methyl-2-phenylglycinamide (1.91 g, 6.57 mM) were placed in a 50 mL round bottom flask. DMF (20 mL) was added and the mixture was cooled to 0° C. and treated with diisopropyl ethylamine (3 mL, 17.52 mM). After the addition was complete the cooling bath was removed and the reaction mixture was stirred at room temperature for 16 h. The mixture was diluted with ethyl acetate (120 mL) and the mixture was washed with 1N HCl (20 mL), water (20 mL) and brine (20 mL). The ethyl acetate was dried with MgSO 4 , filtered and concentrated. The residue was purified by flash column chromatography on silica gel eluting with 5% diethyl ether in CH 2 Cl 2 .
[0442] (d) (S)-5-(2-Butoxy-benzoylamino)-1-methyl-1H-indole-2-carboxylic acid {2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-amide
[0443] To a solution of the product of step (c) (120 mg, 0.22 mM), triphenylphosphine (68 mg, 0.26 mM), and an alcohol (0.29 mM) in THF (2 mL) at 0° C. was added DEAD (41 uL, 0.26 mM). The cooling bath was removed and the mixture was stirred at room temperature for 16 hours. The mixture was concentrated to approximately 200 uL and applied to a prep TLC plate (silica gel 60 F254, 1.0 mm, 20 cm×20 cm). The plate was eluted with 5% diethyl ether in CH 2 Cl 2 . The band corresponding to product was scraped off the plate. The product was washed from the silica gel with ethyl acetate. The ethyl acetate was concentrated to provide the title product. Mol wt. (calc), 602.74; MS, 603; HPLC, 19.7 minutes.
[0444] Examples 87-98 shown in Table 7 were prepared similarly to Example 86.
TABLE 7 Mol wt. Example R 17 (calc.) MS HPLC (min) 87 2-propyl 588.71 589 18.0 88 4-triflouromethylbutyl 656.71 657 18.0 89 2-methylpropyl 602.74 603 19.7 90 2-methylbutyl 616.77 617 21.1 91 2-ethylbutyl 630.79 631 22.3 92 Allyl 586.7 587 17.1 93 Cyclopentyl 614.75 615 20.0 94 Methylcyclohexyl 642.8 643 22.7 95 Methylcyclopropyl 600.72 601 18.5 96 2-phenoxyethyl 666.78 667 18.8 97 2-ethoxyethyl 618.74 619 16.7 98 H 546.63 547 15.3
Example 99
5-[(4′-Trifluoromethyl-biphenyl-2-carbonyl)-amino]-benzofuran-2-carboxylic acid [2-oxo-1-phenyl-2-(propylamino)ethyl]amide
[0445]
[0446] (a) 5-nitrobenzofuran-2-carboxylic acid methyl ester.
[0447] 5-Nitrobenzofuran-2-carboxylic acid (10 g) was dissolved in methanol (200 mL) and chloroform (100 mL), and the mixture was cooled to 0° C. Under stirring conditions was bubbled HCl gas until the solution was saturated. The reaction mixture was stirred at room temperature overnight, and white solid was formed. The precipitate was collected by filtration to afford 9.5 g of the title compound.
[0448] (b) 5-aminobenzofuran-2-carboxylic acid methyl ester
[0449] The product from step (a) (6.9 g) was dissolved in THF (200 mL), followed by the addition of 10% Pd/C (1 g), and the resulting reaction mixture was hydrogenated under 50 psi of hydrogen for 2 hours. The catalyst was removed by filtration through celite, and the solvent was removed in vacuo to provide 5.9 g of the title compound.
[0450] (c) 5-[(4′-Trifluoromethyl-biphenyl-2-carbonyl)-amino]-benzofuran-2-carboxylic acid methyl ester
[0451] 4′-Trifluoromethyl-2-biphenylcarboxylic acid (9.14 g) was dissolved in CH 2 Cl 2 , followed by the addition of oxalyl chloride (4.49 mL). Under stirring conditions was added DMF (0.5 mL), and the stirring was continued for 1 hour. The solvent and excess oxalyl chloride were removed in vacuo, and the residue was dissolved in CH 2 Cl 2 , followed by the addition of product from step (b) (5.8 g) and pyridine (7.36 mL). The reaction solution was stirred at room temperature overnight. The reaction mixture was concentrated in vacuo, and the residue was dissolved in EtOAc (500 mL), washed with saturated NaHCO 3 solution (2×50 mL), water (50 mL), 1N HCl solution (2×50 mL), and brine (50 mL). After drying over MgSO 4 , the solvent was removed in vacuo to give the crude product which was purified by recrystallization from EtOAc/hexane to afford 8.4 g of the title compound.
[0452] (d) 5-[(4′-Trifluoromethyl-biphenyl-2-carbonyl)-amino]-benzofuran-2-carboxylic acid
[0453] The product from step (c) (8.1 g) was dissolved in THF (100 mL) and methanol (100 mL). Under stirring conditions was added LiOH (2 g) in water (100 mL). The reaction mixture was stirred at room temperature for 30 minutes. The reaction solution was then concentrated in vacuo, acidified by adding 1N HCl solution. The product was extracted with ether (2×300 mL), and combined organic layers were washed with brine (2×50 mL) and then dried over MgSO 4 . The organic layer was then concentrated in vacuo to give the crude product which was purified by recrystallization from ether/hexane to give 7.1 g of the title compound.
[0454] (e) 5-[(4′-Trifluoromethyl-biphenyl-2-carbonyl)-amino]-benzofuran-2-carboxylic acid [2-oxo-1-phenyl-2-(propylamino)ethyl]amide
[0455] The product from step (d) (100 mg, 0.235 mmol), (S)-N-propyl-2-phenylglycinamide hydrochloride salt (1 eq.) and PyBrop (1.1 eq.) were dissolved in CH 2 Cl 2 (2 mL), followed by the addition of diisopropylethylamine (3 eq.), and the reaction mixture was stirred at room temperature between 2 hours. The solvent was then evaporated, and the product was purified by prep-TLC using 2:1 EtOAc/hexane as eluting solvent, and the yield was 79 mg.
[0456] Examples 100-112 were prepared similarly to Example 99. In Examples 102, 103 and 108, R 6 and R 7 together with the nitrogen atom to which they are attached form the listed heterocyclyl group.
TABLE 8 Mol wt MS HPLC Example R 6 R 7 (calc) (found) (min) 100 H Cyclopropylmethyl 611.626 612.2 15.311 101 H Cyclopropyl 597.599 598.2 13.539 102 Piperidin-1yl 625.653 626.2 17.696 103 Morpholin-4-yl 627.626 628.2 13.755 104 H Cyclopentyl 625.653 626.2 16.677 105 H 3-fluoro-benzyl 665.65 666.2 16.705 106 H 2-methyl-but-1-yl 627.6689 628.2 17.825 107 Methyl Methyl 585.588 586.2 14.26 108 Azetidinyl 597.599 598.2 13.51 109 H 4-methoxy-benzyl 677.686 678.2 16.075 110 H 3,4-difluoro-benzyl 683.6409 684.2 16.955 111 H 2,3-difluoro-benzyl 683.6409 684.2 16.961 112 H 2-fluoro-4- 733.6489 733.2 18.899 trifloromethyl- benzyl
[0457] Table 9 below provides Examples of additional compounds of the invention, prepared according to the methods described above, in particular, as described for Examples 66-85.
TABLE 9 Mol. Wt. MS HPLC Example R 1 (calc) (found) (min) 113 Isopropylmethyl 524.668 525.2 14.958 114 2-methoxy-phenyl 560.658 561.2 15.07 115 2-methyl-5-chloro-phenyl 579.104 579.2 16.683 116 1-hydroxy-cycloprop-1-yl 552.679 553.2 13.013 117 2-methyl-4-chloro-phenyl 579.104 579.2 16.651 118 (Norborn-2-yl)-methyl 562.718 563.2 17.288 119 Cyclobutyl 508.625 509.2 11.734 120 phenoxy-ethyl-methyl 588.712 589.2 17.118 121 5-bromo-fur-2-yl 599.489 600.2 14.651 122 1-phenyl-cyclopent-1-yl 598.751 599.2 18.913 123 Naphth-1-yl 580.692 581.2 15.995 124 3-chloro-thien-2-yl 571.102 571.2 15.847 125 Perfluoroethyl 572.539 573.2 16.771 126 2-(pyrrol-1-yl)-phenyl 595.707 596.2 15.497 127 Isoquinolin-1-yl 581.68 582.2 16.432
Pharmaceutical Compositions
[0458] Oral solid forms for compounds of the invention, examples of which have been provided above, are preferably tablets, powders or granules which typically contain just the active agent(s) or preferably in combination with adjuvants/excipients to enhance the processing characteristics of the active.
[0459] For tablets, the active agent is typically less than 50% (by weight) of the formulation and preferably less than 10%, for example 2.5% by weight. The predominant portion of the formulation comprises fillers, diluents, disintegrants, lubricants and optionally, flavors. The composition of these excipients is well known in the art. According to this invention, the preferred fillers/diluents comprise admixtures of two or more of the following components: avicel, mannitol, lactose (all types), starch, and di-calcium phosphate. The filler/diluent admixtures typically comprises less than 98% of the formulation and preferably less than 95%, for example 93.5%. The preferred disintegrants include Ac-di-sol, Explotab™, starch and sodium lauryl sulphate (SLS)—also known as wetting agent. When present these agents usually comprise less than 10% of the formulation and preferably less than 5%, for example 3%. The preferred lubricant is magnesium stearate. When present this agent usually comprises less than 5% of the formulation and preferably less than 3%, for example 1%. When present these agents comprise less than 60% of the formulation, preferably less than 40%, for example 10-20%. More detailed examples of tablet formulations for the compounds of the invention are shown in Table 10.
[0460] The examples shown in Table 10 can be manufactured by standard tabletting processes, for example, direct compression or a wet, dry or melt granulation, melt congealing process and extrusion. The tablet cores may be mono or multi-layer(s) and can be coated with appropriate overcoats known in the art.
TABLE 10 Examples of tablet formulations for compounds of formula 1, 2.5% for all formulations below. Disintegrant/ Fillers/Diluents Wetting Agent Flavors Lubricant Avicel/Mannitol Ac-Di-Sol — Magnesium 1:2 (93.5%) 3% Stearate 1% Mannitol/Dcp Ac-Di-Sol — Magnesium 2:1 (93.5%) 3% Stearate 1% Avicel/Dcp Ac-Di-Sol — Magnesium 2:1 (93.5%) 3% Stearate 1% Avicel/ Ac-Di-Sol — Magnesium Fast Flo Lactose 3% Stearate 1:2 (93.5%) 1% Avicel/Mannitol Ac-Di-Sol Brewers Yeast Magnesium 1:2 (73.5%) 3% 20% Stearate 1% Mannitol/Dcp Ac-Di-Sol Brewers Yeast Magnesium 2:1 (73.5%) 3% 20% Stearate 1% Avicel/Mannitol Ac-Di-Sol Magnesium 1:2 (92.5%) 3% + Sls Stearate 1% 1% Avicel/Mannitol Ac-Di-Sol Brewers Yeast Magnesium 1:2 (72.5%) 3% + Sls 20% Stearate 1% 1% Avicel:Mannitol Explotab — Magnesium 1:2 (92.5%) 4% Stearate 1% Avicel/Mannitol Ac-Di-Sol — Sodium Stearyl 1:2 (93.5%) 3% Fumarate 1% Avicel/Dcp Ac-Di-Sol Yeast Extract Magnesium 2:1 (62.5) 3% 10% Stearate Sls = 1% Brewers Yeast 1% 20%
[0461] Oral liquid forms of the compounds of the invention are preferably solutions, wherein the active compound is fully dissolved. Examples of solvents include all pharmaceutically precedented solvents suitable for oral administration and preferably those in which the compounds of the invention show good solubility i.e., polyethylene glycol, polypropylene glycol, edible oils and glyceryl- and glyceride-based systems. Glyceryl- and glyceride-based systems may preferably include the following agents (and similar chemicals thereof), for example: Captex 355 EP, Crodamol GTC/C, or Labrafac CC, triacetin, Capmul CMC, Migyols (812, 829, 840), Labrafil M1944CS, Peceol and Maisine 35-1. The exact composition of these agents and commercial sources are shown in Table 11. These solvents usually make up the predominant portion of the formulation i.e., greater than 50% and preferably greater than 80%, for example 95% and more preferably greater than 99%. Adjuvants and additives may also be included with the solvents principally as taste-mask agents, palatability and flavoring agents, antioxidants, stabilizers, texture and viscosity modifiers, and solubilizers.
TABLE 11 Trademark, chemical composition and commercial source for some glyceryl and glyceride-based systems Commercial Trademark Chemical composition Source Triacetin Glyceryl triacetate Abitec Capmul CMC Glyceryl caprylate/caprate Abitec Miglyol 812 Trigylceride caprate/succinate Condea Miglyol 829 Trigylceride aprylate/caprate/ Condea succinate Miglyol 840 Propylene glycol dicaprylate/ Condea dicaprate Labrafil M1944CS Oleoyl macrogol-6-glycerides Gattefosse Maisine 35-1 Glyceryl monolinoate Gattefosse Peceol Glyceryl monooleate Gattefosse Captex 355 EP Medium-chain triglyceride Abitec Crodamol GTC/C Medium-chain triglyceride Croda Labrafac CC Medium-chain triglyceride Gattefosse
A preferred oral solution for active compounds of the invention contains up to 1% by weight of active ingredient dissolved in medium-chain triglyceride oils Pharm. Eur. or similar solvents (see table 11).
[0462] A more preferred solution contains active compound (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide, of the invention see Example 44, at a concentration up to 0.6 mg per mL in a medium-chain triglyceride oil Pharm. Eur.
[0463] A particulary preferred solution contains active compound (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide, of the invention see Example 44, at a concentration up to 0.6 mg per mL in Captex 355 EP, Crodamol GTC/C, or Labrafac CC.
[0464] An even more preferred solution contains active compound (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide, of the invention see Example 44, at a concentration of 0.5 mg of per mL in Captex 355 EP, or Crodamol GTC/C.
[0465] The preferred solutions above may be prepared in a process involving combining the components with mechanical or ultrasonic agitation at a temperature, in such a fashion that is advantageous to the rate of dissolution.
[0466] A more preferable process involves combination of the components with mechanical agitation at a temperature up to 70° C., followed by filtration to ensure solution clarity.
[0467] A particularly preferable process involves addition of the active ingredient (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide, of the invention see Example 44, with mechanical agitation, to the Captex 355 EP, Crodamol GTC/C, or Labrafac CC that has been pre-heated to a temperature up to 70° C., followed by cooling and filtration to ensure solution clarity.
[0468] An even more preferable process involves addition of the active ingredient (S)-N-{2-[benzyl(methyl)amino]-2-oxo-1-phenylethyl}-1-methyl-5-[4′-(trifluoromethyl)[1,1′-biphenyl]-2-carboxamido]-1H-indole-2-carboxamide, of the invention see Example 44, with mechanical agitation, to the Captex 355 EP, Crodamol GTC/C, that has been pre-heated to a temperature 50° C.-70° C., followed by cooling and filtration to ensure solution clarity.
[0469] The invention is not to be limited in scope by the specific embodiments described which are intended as single illustrations of individual aspects of the invention, and functionally equivalent methods and components are within the scope of the invention. Indeed, various modifications of the invention, in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description and following examples. Such modifications are intended to fall within the scope of the appended claims.
[0470] All references cited herein are incorporated by reference in their entireties for all purposes. | The invention relates to triamide MTP/ApoB inhibitors of the formula 1
wherein R 1 -R 8 are as defined in the specification, as well as pharmaceutical compositions and uses thereof, and processes for preparing the compounds. The compounds of the invention are useful for the treatment of obesity and lipid disorders. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 11/369,779 filed Mar. 7, 2006, which is a divisional of U.S. application Ser. No. 10/313,554, filed Dec. 6, 2002, both of which are hereby incorporated herein in their entirety by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates generally to an apparatus and method for providing access to items to be dispensed, and relates more particularly to the automatic dispensing of medical supplies. The invention further relates to an apparatus and method for reducing the amount of power consumed by an automatic dispensing system.
[0004] 2. Description of the Related Art
[0005] In typical medical facilities (for example, hospitals, clinics, rest homes, etc), medical supplies are maintained in centralized storage locations and delivered to remote locations (for example, an emergency room, patient ward, etc.) as needed. Once delivered, the medical supplies are then dispensed to a patient. “Medical supply” is intended to include, among others, any item that is administered to or dispensed for a patient or used by a medical caregiver to treat a patient (for example, pharmaceuticals, syringes, sterilized bandages, scalpels, etc.). The invention has been described herein with reference to the dispensing of medical supplies, but it should be recognized that the invention is applicable to fields other than the medical field.
[0006] A variety of systems are used for transferring (i.e., from the storage location to the remote locations) and for dispensing (i.e., from the remote locations to the patient) the medical supplies. A system may use, for example, mobile dispensing carts which are stocked at the centralized storage area and then wheeled to the remote location. The medical supplies may then be dispensed directly from the mobile dispensing cart for administering to the patient. Alternatively, a dispensing system may use a stationary dispensing cabinet located at the remote location. Medical supplies are dispensed from the dispensing cabinet for later administering to the patient. A restocking cart, loaded with replacement medical supplies from the centralized storage location, is used to replenish the stationary dispensing cabinet.
[0007] Of particular interest to the present invention are dispensing systems which dispense items which require close monitoring and control. A variety of schemes have been proposed for providing secured access to items that are held within such dispensing systems, including locking the items within the carts or allowing access to only one item at a time (commonly referred to as “single dose” or “unit dose” dispensing). In addition to providing secure access, the schemes direct the user to the location within the dispensing system of the item to be dispensed.
[0008] One such system is described in related U.S. Pat. No. 5,745,366 entitled “Pharmaceutical Dispensing Device and Methods” and No. 5,905,653 entitled “Methods and Devices for Dispensing Pharmaceutical and Medical Supply Items.” The system controls access to items to be dispensed and maintains an inventory of the items. The system includes a dispensing unit having a plurality of storage locations distributed within an enclosure. The storage locations may include a multiplicity of lockable receptacles disposed within at least some of the storage locations. The storage locations and the individual lockable receptacles may have sensors and indicator lights associated therewith.
[0009] A processor is operable to receive user input and, in response to the input, is operable to activate an indicator light corresponding to the storage location associated with the item to be dispensed. The processor activates locks to prevent access to non-selected storage locations. The processor unlocks the individual receptacle (within the selected storage location) containing the item to be dispensed and activates the indicator light corresponding to the unlocked receptacle. The processor is also connected to receive feedback signals from the receptacle-associated sensors, such that when the unlocked receptacle is opened by a user, a feedback signal is sent to the processor indicating that the item has been dispensed.
[0010] Another such system is described in related U.S. Pat. No. 6,109,774 entitled “Drawer Operating System” and No. 6,065,819 entitled “Jerk-Resistant Drawer Operation System.” The patents disclose a drawer operating system for controlling a plurality of elongated drawers having a plurality of bins consecutive with one another along a sliding direction for holding various dispensable items. The drawers are housed in an array in a cabinet, each drawer arranged to move independently between a closed position and graduated, progressively opened positions to allow access to one or more bins and the contents stored therein. The system controls access to the bins by only allowing the drawer to travel the distance necessary to expose the next bin containing the item. For example, if a drawer has five bins each containing the desired item, the system will only allow the drawer to move to a position in which the first bin is exposed. After the first bin is emptied, the system will only allow the drawer to move to a position in which the second bin is exposed. The process may be repeated until all five bins are emptied. The system includes a keyboard for inputting coded information concerning the particular item needed and information as to the party entering the information.
[0011] U.S. Pat. No. 6,011,999 entitled “Apparatus for Controlled Dispensing of Pharmaceutical and Medical Supplies” discloses a system for controlled dispensing of pharmaceutical and medical supplies. The system includes a cabinet having a plurality of drawers, each having a plurality of receptacles. Each receptacle is sized to hold one item and has an identifier associated therewith. Locks are provided for securing the lid. The locks include an electrically responsive actuator wire, which in response to an electrical current supplied to the electrically responsive actuator wire, causes the lock to engage and disengage the lid. A processor is in communication with the locks and is configured to send a signal to the electrically responsive actuator wire to actuate the lid. The lid is spring biased and includes a colored indicator on an inner portion of the lid, such that when unlocked, the lid pops open and the indicator is exposed.
[0012] U.S. Pat. No. 6,116,461 entitled “Method and Apparatus for the Dispensing of Drugs” discloses another dispensing system. The system includes modular receptacles which are filled and transported to remote automatic dispensing machines for later retrieval and distribution. The system includes the loading, refilling, and replacement of the modular receptacles at various stages in the process of the invention. The system includes a receptacle having a lockable lid. When required an electronic circuit causes a latch to be actuated, thus opening the lockable lid. The lid has a spring in the hinge assembly which pushes the lid open when the latch is freed, thus indicating to the user the correct receptacle.
[0013] U.S. Pat. No. 5,520,450 discloses a supply station with an internal computer. The supply station is comprised of a cabinet having a plurality of lockable doors. Information is provided to the computer which unlocks the doors and simultaneously and automatically updates a patient's record, billing information and hospital inventory. Relevant data may be displayed on a display or printed on a sheet of paper by a printer connected to the computer.
[0014] U.S. Pat. No. 5,346,297 discloses an auxiliary storage and dispensing unit for use with a computer-controlled supply and medication dispenser station. The dispensing unit includes a cabinet having a plurality of lockable doors, a device for interconnecting one or more of the doors to allow access to the cabinet and a door unlocking device interconnected to the computer-controlled station for selectively unlocking one or more of the doors as a function of information inputted to the station.
[0015] Computer controlled dispensing systems, such as those discussed above, have been developed in response to a number of problems existing in medical facilities. Computer controlled dispensing systems, for example, address problems such as the removal of medications by unauthorized personnel, dispensing the wrong medication for a patient, inaccurate record keeping, etc.
[0016] The AcuDose-Rx dispensing cabinet available from McKesson Automation Inc. of Pittsburgh, Pa. is an example of a computer controlled cabinet programmed to address the aforementioned problems. A user is required to logon to the computer (thereby identifying who is removing medications). After identifying a patient, the user is presented with a list of medications that have been approved for administering to the identified patient (thereby addressing the problem of incorrect dispensing). Records are kept for each dispensing event thereby creating an audit trail.
[0017] As discussed above, a variety of different storage options are available for dispensing cabinets to ensure the safe and accurate dispensing and administration of medications. These include, but are not limited to, drawers with individual locking pockets which provide access to only one medication in a drawer at any given time; unit-dose dispensing drawers, which provide access to one “unit-of-use” of a medication at any given time, and open matrix drawers, which consist of a plurality of open pockets and which provide access to multiple medications at any given time.
[0018] While such systems provide for access controlled dispensing, most require large amounts of power to keep the compartments locked. Furthermore, systems using lighted indicators require additional power, control circuitry, and wiring. In contrast, systems using non-lighted indicators rely on the drawer or lid to “spring” open. If an item is caught on the drawer or lid, an increased risk is encountered that the item will become airborne when the drawer or lid is opened. The airborne item may become lost or may strike a user.
[0019] Thus, a need exists for a secure unit dose dispensing cabinet that requires less power to operate and provides a mechanical indicator means for notifying the user of correct location of the item to be dispensed without “springing” open a drawer or lid. Additionally, there exists a need for a safer, less error-prone dispensing and replenishment system.
BRIEF SUMMARY OF THE INVENTION
[0020] One aspect of the present invention relates to an assembly comprising a plurality of bins, a plurality of lids each associated with one of the plurality of bins, wherein each of the bins has a notched tab and a touch latch. The notched tab and the touch latch are in one of an engaged state and a disengaged state when said lid is in a closed position. The assembly includes a lock assembly including a catch operable to prevent the notched tab and the touch latch from changing state and a mechanical indicator responsive to the catch.
[0021] Another aspect of the present invention relates to an automated dispensing cabinet, comprising a plurality of drawers, wherein at least one of the drawers includes a plurality of row assemblies, each of the row assemblies having a plurality of bins. Each of the plurality of bins includes a lid having a tab attached thereto, a touch latch operable to one of engage and disengage the tab when the lid is in a closed position, a lock assembly including a catch operable to prevent the notched tab and the touch latch from one of engaging and disengaging, and a mechanical indicator responsive to the lock assembly and viewable when the lid is in a closed position. The automated dispensing cabinet also includes a control computer operable to lock and unlock the plurality of drawers and to control the position of the catch of each of the bins.
[0022] Additionally, an aspect of the present invention relates to a method for dispensing an item contained in remote dispensing system. The method comprises granting a user access to the remote dispensing system having a plurality of lockable drawers with a plurality of lockable bins, accepting dispensing information from the user, unlocking at least one of the plurality of drawers, wherein the unlocked drawer contains an item to be dispensed, unlocking at least one of the plurality of bins located within the unlocked drawer while changing the state of a mechanical indicator associated with a bin that has been unlocked, verifying that the user has closed the unlocked bin, and locking the at least one of the plurality of bins and the at least one of the plurality of drawers.
[0023] Another aspect of the present invention relates to a method for restocking items contained in a remote dispensing system including a cabinet having with a plurality of drawers, at least one of the plurality of drawers having a plurality of bin row assemblies. The method comprises selecting a bin row assembly, opening the drawer containing the bin row assembly, identifying the selected bin row assembly, removing the selected bin row assembly from the drawer, inserting a restocked bin row assembly in place of the removed selected bin row assembly.
[0024] Yet another aspect of the present invention relates to an assembly comprising a plurality of bins, a plurality of lids, each lid being associated with one of the plurality of bins, each of the bins having a notched tab, a lock assembly including a catch operable to one of engage or disengage the notched tab when the lid is in a closed position, and a mechanical indicator responsive to the catch.
[0025] Those advantages and benefits, and others, will be apparent from the Detailed Description below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] To enable the present invention to be easily understood and readily practiced, the present invention will now be described for purposes of illustration and not limitation, in connection with the following figures wherein:
[0027] FIG. 1 is a perspective view of a dispensing system located at a decentralized location according to one embodiment of the present invention.
[0028] FIG. 2 is a perspective view of a lockable drawer for the dispensing system shown in FIG. 1 according to one embodiment of the present invention.
[0029] FIG. 3A is a perspective view of a bin row assembly for the lockable drawer shown in FIG. 2 according to one embodiment of the present invention.
[0030] FIG. 3B is a front view of a the bin row assembly of FIG. 3A according to an embodiment of the present invention.
[0031] FIGS. 3C and 3D are left and right side views, respectively, of the bin row assembly of FIG. 3A according to an embodiment of the present invention.
[0032] FIG. 3E is a top view of the bin row assembly of FIG. 3A according to an embodiment of the present invention.
[0033] FIG. 3F is an exploded view of the bin row assembly of FIG. 3A according to an embodiment of the present invention.
[0034] FIGS. 3G and 3H illustrate a touch latch in the unhooked and hooked positions, respectively according to one embodiment of the present invention.
[0035] FIG. 4A illustrates a power control circuit board for the bin row assembly of FIG. 3A according to one embodiment of the present invention.
[0036] FIG. 4B is a detailed view of a portion of the power control board for the bin row assembly illustrated in FIG. 4A according to one embodiment of the present invention.
[0037] FIG. 4C is an exploded view of a portion of the power control board for the bin row assembly of FIG. 3A according to one embodiment of the present invention.
[0038] FIG. 4D is a sectional view taken along the lines A-A of the portion of the power control board for the bin row assembly illustrated in FIG. 4B .
[0039] FIG. 5 illustrates an operational process for dispensing items from the remote dispensing system shown in FIG. 1 according to an embodiment of the present invention.
[0040] FIG. 6 illustrates an operational process for restocking dispensed items from the remote dispensing system shown in FIG. 1 according to an embodiment of the present invention.
[0041] FIGS. 7A-7C are an electrical schematic of an input/output interface circuit and a manually activated override interface circuit for the remote dispensing system illustrated in FIG. 1 according to an embodiment of the present invention.
[0042] FIGS. 8A and 8B are an electrical schematic of a relay select circuit for the remote dispensing system illustrated in FIG. 1 according to an embodiment of the present invention.
[0043] FIGS. 9A and 9B are an electrical schematic of a manual override sequence control circuit for the remote dispensing system illustrated in FIG. 1 according to an embodiment of the present invention.
[0044] FIG. 10 is an electrical schemata of feedback circuits for the remote dispensing system illustrated in FIG. 1 according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0045] FIG. 1 is a perspective view of a remote dispensing system 10 located at a decentralized location according to one embodiment of the present invention. The system 10 illustrated in FIG. 1 may be comprised of, for example, an AcuDose-Rx™ cabinet 12 (available from McKesson Automation inc., 700 Waterfront Drive, Pittsburgh, Pa.) having a control computer 14 , and an AcuDose-Rx™ auxiliary cabinet 16 . A supply tower 18 is also illustrated. The control computer 14 controls the operation of the cabinet 12 , auxiliary cabinet 16 , and supply tower 18 .
[0046] The control computer 14 may include a memory device (not shown, such as a disk drive, tape drive, CD-ROM drive, etc.) having a local database. The local database may contain inventory, user, and patient information (among others). Alternatively, the control computer 14 may be in communication with another computer (for example, located at the centralized storage location) having a central database which contains the inventory, user, and patient information (among others).
[0047] The control computer 14 accepts entry of inventory, user, patient, and other information via a keyboard 20 , scanning device 22 , and datalink (not shown), among others. The control computer 14 , in programmed interaction with the entered information, provides output information to a display 24 , printer (not shown), etc. and provides output control signals to the cabinet 12 , auxiliary cabinet 16 , and supply tower 18 , etc.
[0048] The control computer 14 may be programmed to regulate access to the system's cabinets 12 , 16 and supply tower 18 and to generate records related to access, inventory, etc. The records may be stored in the local database, displayed on the display 24 , printed by a printer unit, or transmitted to a central database (among others). The control computer 14 may be preprogrammed with appropriate information regarding the medication types associated with, and their exact location within, each cabinet 12 , auxiliary cabinet 16 and supply tower 18 . The programming may, for example, be entered directly into the control computer 14 or downloaded from the central database.
[0049] As will be discussed in greater detail in conjunction with FIGS. 5 and 6 , a user logs onto the control computer 14 to perform a dispensing operation. After log-on, patient information and information regarding items to be dispensed are entered. Based on the entered information, the appropriate drawers 26 in the cabinet 12 and the auxiliary cabinet 16 , and various doors 28 on the supply tower 18 are unlocked. The user then accesses the unlocked drawers 26 and doors 28 and removes the appropriate item. After the item to be dispensed has been removed, its removal is recorded at the control computer 14 . The record may be entered manually by the user or automatically by a feedback signal. The user may continue to dispense items for the identified patient, enter patient information for another patient, or logoff.
[0050] Entry of information, including log-in, can be performed in a variety of ways with a variety of input devices, for example, using the keyboard 20 and barcode scanning 22 . Additional input devices or input means, for example, a touch screen, selecting items from a pick list, RF ID), flash memory, magnetic strips, OCR (none of which are shown), etc., may also be used. The reader will understand that the hardware illustrated in FIG. 1 is exemplary and is illustrated for purposes of demonstrating one type of hardware which may be located at the decentralized location.
[0051] The hardware illustrated in FIG. 1 limits access to the items to be dispensed to those individuals who have properly logged on. Thus, the hardware illustrated in FIG. 1 is referred to as a closed system for performing dispensing operations because a dispensing operation cannot be performed unless the user is identified to, and recognized by, the control computer 14 .
[0052] It should be noted that in the current embodiment, a limited access manual override system is also provided. Access is limited to individuals having keys to the rear of the AcuDose-Rx cabinet 12 , AcuDose-Rx auxiliary cabinet 16 , and AcuDose-Rx supply tower 18 .
[0053] FIG. 2 is a perspective view of one type of a lockable drawer 26 for use with the dispensing system 10 shown in FIG. 1 according to one embodiment of the present invention. For example, the lockable drawer 26 may be one of the drawers 26 from the AcuDose-RxTM cabinet 12 or from the auxiliary cabinet 16 . Lockable drawer 26 is comprised of a housing 30 , a frame 31 , and a pair of slides 32 (one of which is seen in FIG. 2 ) which enable the frame 31 to move relative to the housing 30 . As illustrated in FIG. 2 , five (5) bin row assemblies 34 , each having five (5) bins 36 are secured to the frame 31 . The frame 31 and bin row assemblies 34 are slidably moveable between a closed position within the housing 30 and an open position outside of the housing 30 . It should be noted that the housing 30 may have a single frame 31 (with a plurality of bin row assemblies 34 secured thereto, for example, as shown in FIG. 2 ) or with a number of frames 31 (each having a single bin row assembly 34 secured thereto, for example) each mounted on corresponding slides 31 .
[0054] For simplicity, in the current embodiment the bins 36 are numbered from left-to-right and from back-to-front, relative to the lockable drawer 26 . Thus as illustrated, the first bin row assembly 34 is comprised of bins 1 - 5 , the second bin row assembly 34 is comprised of bins 6 - 10 , the third bin row assembly 34 is comprised of bins 11 - 15 , etc. It should be noted that the number of bin row assemblies 34 per drawer 26 , the number of bins 36 per bin row assembly 34 , and the scheme used to number the bin row assemblies 34 and bins 36 may be altered while remaining within the scope of the present invention.
[0055] The bin row assemblies 34 , to facilitate restocking procedures or changing of inventory, are separable from the open drawer 26 . For example if the bins 6 - 10 need to be restocked, the second bin row assembly may be removed from the open drawer 26 , taken to the central storage location, restocked, and then returned to the open drawer 26 , or swapped out with another bin row assembly, i.e., the second bin row assembly may be removed from the open drawer 26 and a previously stocked replacement bin row assembly 34 may be substituted in place of the second bin row assembly.
[0056] FIGS. 3A-3F are perspective, front, left side, right side, top, and exploded views, respectively, of a bin row assembly 34 for the dispensing system 10 shown in FIG. 1 according to one embodiment of the present invention. As best seen in FIG. 3E , the bin row assembly 34 is comprised of a base 38 , front wall 40 , back wall 42 , side wall 44 , and interior partitions 46 . As illustrated, the bin row assembly 34 in the current embodiment contains five (5) bins 36 . The front wall 40 includes a lip 48 and one or more spacers 50 configured to receive a power control circuit board 52 . The power control circuit board 52 is positioned under the lip 48 , abutting the spacers 50 , and attached to the front wall 40 (for example, with screws). The lip 48 includes a slotted indicator window 54 and a latching mechanism aperture 56 for each bin 36 .
[0057] A lid 58 is attached to the back wall 42 of each bin 36 via a hinge mechanism 60 . When the lid 58 is in the closed position, a notched tab 62 on the lid 58 enters the aperture 56 in the lip 48 and engages with a touch latch 63 that is mounted to the bin 36 (for example, on the lip 48 under the aperture 56 , among others). The touch latch 63 , as is known in the art, operates by pushing the notched tab 62 on the lid 58 into the touch latch 63 . The notched tab 62 “hooks” with the touch latch 63 . Referring briefly to FIG. 3H , a touch latch is illustrated in the hooked position. Thus, the lid 58 is closed it by pushing it down until the touch latch 63 latches and holds it closed. The lid 58 is opened by pushing down on the lid 58 again which causes the touch latch 63 to release (i.e., “unhook”) the lid 58 . Referring briefly to FIG. 3G , a touch latch is illustrated in the unhooked position.
[0058] When closed, the lid 58 may be locked in place by a lock assembly 66 (shown in FIGS. 4A-4C ) contained on the power control circuit board 52 . In the current embodiment, each bin 36 has a lid 58 associated therewith. Additionally, each lid 58 may be constructed of a transparent material so that both the contents of the bin 36 and the slotted indicator window 54 can be viewed when the lid 58 is in the closed position.
[0059] When a lid 58 is in the closed position (i.e., engaged by the touch latch 63 ) and locked by the lock assembly 66 , the slotted indicator window 54 displays a first color (for example, red) indicating to the user that the lid 58 cannot be opened. When the lid 58 is unlocked by the lock assembly 66 , the slotted indicator window 54 displays another color (for example, green) indicating to the user that the lid 58 can be opened. It should be noted that in the current embodiment, the indicator can be viewed even when the lid 58 remains closed. It should further be noted that other types of mechanical indicators may be used that permit the indicator to be viewed when the lid 58 is closed while remaining within the scope of the present invention.
[0060] It should be noted that an assembly having an alternative latching/locking means may be used while remaining within the scope of the present invention. For example, a lid 58 may have a notched tab 62 that is engaged by the lock assembly 66 without using a touch latch 63 . In one instance, the lock assembly's catch 74 may engage the notched tab 62 when the lid is in a closed position.
[0061] It should further be noted that, although the bin row assembly 34 of the current embodiment has five (5) bins, the number of bins 36 may be varied while remaining with the scope of the present invention. Additionally, certain bins 36 may not have a lid 58 associated therewith, for example, a bin 36 containing non-regulated supplies may not have a lid 58 .
[0062] FIG. 4A illustrates a power control circuit board 52 for the bin row assembly 34 of FIG. 3A according to one embodiment of the present invention. FIGS. 4B-4D are detailed, exploded, and sectional views of a portion of the power control circuit board 52 for the bin row assembly 34 illustrated in FIG. 4A according to one embodiment of the present invention.
[0063] Referring to FIG. 4A , power control circuit board 52 is comprised of a backing plate 64 with five (5) latch assemblies 66 (i.e., one associated with each bin 36 ) and a connector 68 attached thereto. The connector 68 is used to connect signal and power conductors for each lock assembly 66 to the system 10 . For example, the connector 68 couples with a complimentary connector (not shown) that is in electrical communication with the control computer 14 . The complimentary connector in the present embodiment is located on the drawer 26 .
[0064] As best seen in FIG. 4C , in the current embodiment each locking assembly 66 includes a solenoid 70 , pivot arm 72 , catch 74 . The catch 74 , in the current embodiment, includes the mechanical indicator for notifying the user whether the bin 36 is locked or unlocked. The lock assembly 66 may also include a relay 82 , Hall-effect sensor 84 , as well as associated hardware, for example, flat washers 76 , fastener standoff 78 , and screws 80 , among others.
[0065] In the current embodiment, latching solenoids 70 are used. A latching solenoid 70 refers to a solenoid 70 that does not have a default mechanical state and must receive an electrical pulse to change states. For, example in the current embodiment, the catch 74 slides from side to side to lock and unlock the lid 58 . When the catch 74 is engaged (i.e., the lid 58 is locked), the notched tab 62 of the lid 58 is prevented from being pushed down far enough to change the state of (i.e., engage or disengage) the touch latch. If power is removed from the latching solenoid 70 , the catch 74 remains engaged. The catch 74 remains engaged until a control pulse is applied to the latching solenoid 70 . Likewise, when a bin 36 is unlocked, the catch 74 is disengaged. If power is removed from the latching solenoid 70 , the catch 74 remains disengaged. The catch 74 remains disengaged until a control pulse is applied to the latching solenoid 70 . Thus, the use of latching solenoids 70 reduces the amount of power needed to operate the dispensing system 10 . It should be noted that other means for moving the catch 74 (for example, a non-latching solenoid, a motor, a pneumatic or hydraulic cylinder, an actuator, an electromagnet, etc.) may be used while remaining within the scope of the present invention.
[0066] Referring now to FIG. 4B , the lock assembly 66 is shown in the locked (i.e., engaged) position. For simplicity, the notched tab 62 and touch latch 63 are not shown in FIG. 4B . When an electrical pulse is applied via the relay 82 to the solenoid 70 , the solenoid plunger 71 extends (moves to the left as shown), causing the pivot arm 72 to rotate clockwise about its pivot point. The pivot arm 72 , in turn, causes the catch 74 to unlock (i.e., move to the right as shown) the lid 58 . When the lock assembly 66 is in the disengaged position and an electrical pulse with opposite polarity is applied to the solenoid 70 via the relay 82 , the solenoid plunger 71 retracts (moves to the right as shown), causing the pivot arm 72 to rotate counterclockwise about its pivot point. The pivot arm 72 , in turn, causes the catch 74 to unlock (i.e., move to the left as shown) the lid 58 . The Hall-effect sensor 84 produces a feedback signal (that is sent to the control computer 14 ) indicative of whether the lid 58 is closed or open.
[0067] As discussed above, when the lock assembly 66 is engaged, the notched tab 62 of the lid 58 is prevented from being pushed down far enough to change the state of (i.e., engage or disengage) the touch latch 63 . Thus, it should be apparent to one skilled in the art that the direction of travel of the catch 74 to lock and unlock the lid may be changed while remaining within the scope of the present invention.
[0068] In the current embodiment, the locking/unlocking and the mechanical indication of the bin's status (i.e., locked or unlocked) are combined in a unitary function, i.e., as the bin is locked or unlocked, the mechanical indicator changes state. The catch 74 , for example, may have an indicia (such as colors, words, symbols, marks, etc.) representative of whether the catch is engaged (i.e., the bin 36 is locked) or disengaged (i.e., the bin 36 is unlocked). For example as discussed in conjunction with FIGS. 3A-3F , catch 74 may have red colored portions and green colored portions which show through the indicator window 54 when the bin in locked and unlocked, respectively. It should be noted, however, that other mechanical indicia, such as raising a flag or pin, rotating a cylinder having “locked” on one portion and “unlocked” on another portion, turning a dial, etc. may be used while remaining within the scope of the present invention. Also, the function need not be unitary, that is, the bin may be locked or unlocked followed by the mechanical indicator changing state. It should be apparent to one skilled in the art that any mechanical indicator that is responsive to the lock assembly 66 may be used while remaining within the scope of the present invention.
[0069] FIG. 5 illustrates an operational process 500 for dispensing items at a remote dispensing system 10 according to an embodiment of the present invention. Operation 500 is initialized by a user logging onto the remote dispensing system's control computer 14 at operation 501 . In the current embodiment, the remote dispensing system 10 includes a control computer 14 , AcuDose-Rx cabinet 12 , AcuDose-Rx auxiliary cabinet 16 , and a supply tower 16 as discussed in conjunction with FIG. 1 .
[0070] After logging onto the control computer 14 , the user is granted access to the remote dispensing system 10 in operation 502 . In the current embodiment, the access may be either restricted or unrestricted. Restricted access allows the user to access fewer than all of the drawers 26 and bins 36 located at the remote dispensing station 10 and prevents the user from removing some or all of the bin row assemblies 34 from a drawer 26 . On the contrary, unrestricted access allows the user access to all of the drawers 26 and bins 34 located at the remote dispensing station 10 and allows the user to removing all of the bin row assemblies 34 from a drawer 26 .
[0071] The control computer 14 then accepts dispensing information from said user in operation 503 . In the current embodiment, dispensing information may include inventory, user, patient, and prescription information, among others. The dispensing information may be entered via a keyboard 20 , scanning device 22 , and datalink (not shown), among others.
[0072] After accepting the dispensing information, the drawers 26 containing the items to be dispensed are unlocked in operation 504 . In the current embodiment, the control computer 14 , in programmed interaction with the entered information, provides the output control signals for unlocking the drawers 26 of the cabinet 12 , auxiliary cabinet 16 , and supply tower 18 .
[0073] The bins 36 within the unlocked drawers 26 , which contain the items to be dispensed, are unlocked in operation 505 . In the current embodiment, the bins 36 contain a mechanism that not only locks/unlocks the bin 36 , but also simultaneously indicates to the user whether the bin 36 is locked or unlocked. In the current embodiment, a mechanical indicator is used which can be viewed when the bin's lid 58 is closed. It should be noted that even when unlocked, the bin's lid 58 remains closed until lifted by the user, or the lid can be spring loaded so the pushing down on an unlocked lid causes the lid to spring up.
[0074] Once the bin(s) 36 have been unlocked, the user can remove the desired item and close the bin lid 58 . Typically, the user then enters information into computer 14 to create a dispensing record. In the current embodiment, feedback signals are sent from the bins 36 to the control computer. The feedback signals may be used, among others, to verify whether a drawer 26 , bin 36 , etc. is locked or unlocked, and whether a bin's lid 58 is opened or closed.
[0075] After the remote dispensing station 10 verifies that the user has closed the unlocked bin(s) 36 and closed the drawer 26 in operation 506 , the closed bins 36 and closed drawer 26 are locked in operation 507 . As discussed above, the mechanism used not only locks/unlocks the bin 36 , but also simultaneously indicates to the user whether the bin 36 is locked or unlocked. A mechanical indicator is used which can be viewed when the bin's lid 58 is closed.
[0076] After the opened bins 36 and drawers 26 are locked in operation 507 , the user indicates whether another dispense is desired in operation 508 . If another dispense is desired, operational process 600 returns to operation 603 and the user enters new dispensing information. If another dispensing operation is not desired, the user is logged off of the control computer 14 in operation 509 .
[0077] FIG. 6 illustrates an operational process 600 for restocking dispensed items with the remote dispensing system 10 according to an embodiment of the present invention. Operation 600 is initiated by operation 601 when the remote dispensing system 10 detects that a bin row assembly 34 within the remote system 10 is depleted or below par (i.e., below an acceptable inventory level). In the current embodiment, the control computer 14 may be manually notified by a user, notified by a centralized computer, or the control computer 14 may automatically detect, that a bin row assembly 34 has been selected (i.e., it is depleted or below par).
[0078] The remote dispensing system 10 then unlocks the drawer 26 containing the selected bin row assembly 34 in operation 602 . In the current embodiment, the user is notified of which drawer 26 has been unlocked on the control computer display 14 . Alternatively, an indicator located on the cabinet or auxiliary cabinet may also be used to notify the user.
[0079] The selected bin row assembly 34 , within the unlocked drawer 26 , is then identified in operation 603 . In the current embodiment, the selected bin row assembly 34 is identified on the control computer display 24 . Alternatively, an indicator located on the drawer, cabinet, or auxiliary cabinet may also be used to identify the selected bin row assembly 34 .
[0080] After the selected bin row assembly 34 has been identified, the user removes the selected bin row assembly 34 from the drawer 26 in operation 604 . In one embodiment, the bin row assembly 34 can be secured within the drawer 26 such that a user having restricted access (as discussed in conjunction with FIG. 5 ) can only remove the selected bin row assembly 34 from the drawer 26 that has been unsecured by the control computer 14 . The user having restricted access is unable to remove the bin row assemblies that remain secured.
[0081] A restocked bin row assembly 34 is then inserted into the drawer 26 in operation 605 . In the current embodiment, the restocked bin row assembly 34 is filled at a centralized storage location. Each bin in the restocked bin row assembly 34 is locked at the centralized storage location, prior to transporting the restocked bin row assembly 34 to the remote dispensing system 10 . After the restocked bin row assembly 34 is inserted into the unlocked drawer 26 and the drawer 26 is closed, the control computer 14 locks the drawer 26 in operation 606 . Operational process 600 is then terminated in operation 607 .
[0082] FIGS. 7A-7C are an electrical schematic of an input/output interface circuit 86 and a manual override interface circuit 94 for the remote dispensing system 10 illustrated in FIG. 1 according to an embodiment of the present invention. The input/output interface circuit includes filters 87 , flip-flops 88 , inverters 89 , and buffers 90 , among others. Column select and row select input bits on pins 91 , sent from control computer 14 , are received by the input output interface circuit 86 , inverted, buffered and output to a relay select circuit 92 (discussed in conjunction with FIG. 8 ) via row select and column select pins 93 . FIG. 7 also illustrates a manual override interface circuit 94 , which in conjunction with a flip-flop 88 A, may be used to disable the row and column select inputs 91 should a manual override be instituted. FIG. 7 also illustrates a start transaction bit carried on line 102 which is input to a power drive 104 through a one-shot 106 . Finally, a flip-flop 88 is used to generate signals for determining the direction needed to drive the solenoids 70 . It should be noted that alternative input/output interface and manual override interface circuits may be used while remaining within the scope of the present invention.
[0083] FIG. 8 is an electrical schematic of a relay select circuit 92 for the remote dispensing system 10 illustrated in FIG. 1 according to an embodiment of the present invention. In the current embodiment, the relay select circuit 92 has a row select circuit 108 and a column select circuit 110 that receive signals from the row select and column select pins 93 of the input/output interface circuit 86 . The row select circuit 108 and column select circuit 110 each fire one of a plurality of output lines that feed a grid or matrix of relay circuits 95 . In the current embodiment, each bin 36 in the remote dispensing station 10 has a corresponding relay circuit 95 . If a given relay circuit 95 receives both a row select signal (e.g., “X”) and a column select signal (e.g., “Y”), the relay for that “X-Y” coordinate is selected. The output of the relay circuit 95 is used to pulse the latching mechanism's 66 latching solenoid 70 for the desired bin 36 , thus locking or unlocking the bin 36 . It should be noted that an alternative relay select circuits or other circuits may be used to actuate the latching mechanism 66 for locking and unlocking the bins 36 while remaining within the scope of the present invention.
[0084] FIG. 9 is an electrical schematic of a manual override sequence control circuit 96 for the remote dispensing system 10 illustrated in FIG. 1 according to an embodiment of the present invention. The circuit of FIG. 9 is comprised of a pair of counters that enable each bin 36 of a selected drawer 26 to be separately and sequentially addressed and unlocked, before proceeding to the next drawer and separately and sequentially addressing and unlocking all of the bins 36 in that drawer 26 . In this manner, the power requirements are maintained at an acceptable level. A similar scheme could be implemented with the control computer 14 if it is still functioning and an override is needed for some reasons other than a control computer 14 malfunction. It should be noted that the actual sequence employed, as well as the auto-sequence circuit used for the manual override (among others) may be varied while remaining within the scope of the present invention.
[0085] FIG. 10 is an electrical schematic of a portion of a feedback circuit for the remote dispensing system 10 illustrated in FIG. 1 according to an embodiment of the present invention. As discussed, the latching mechanism 66 for each bin 36 produces one or more feedback signals. For example, a feedback signal may indicate that the lid 58 is opened or closed (e.g., designated as 0 /C in FIG. 10 ). In the current embodiment, the feedback signal for the bins 36 in each column (i.e., within a drawer 26 ) are sent to a feedback selector 114 . It should be noted that only one feedback selector 114 is shown in FIG. 10 for simplicity. Although not shown in FIG. 10 , the feedback circuit includes a number of feedback selectors 114 to receive feedback from each bin 36 . The output of the feedback selectors 114 are then sent to the control computer 14 (e.g., via pin PORT 3 BIT 0 ). It should be noted that other feedback circuits may be used while remaining within the scope of the present invention.
[0086] It should be recognized that the above-described embodiments of the invention are intended to be illustrative only. Numerous alternative embodiments may be devised by those skilled in the art without departing from the scope of the following claims. | One aspect of the invention relates to an assembly comprising a plurality of bins with a plurality of lids associated therewith. Each of the bins has a lock assembly that includes a catch operable to lock the lid in its closed position and a mechanical indicator responsive to the catch. Another aspect of the invention relates to an automated dispensing cabinet that includes a control computer and a plurality of drawers having a plurality of row assemblies therein. Each row assembly has bins that include a tabbed lid, a lock assembly with a catch operable to engage and disengage the tab, and an indicator responsive to the lock assembly. Methods for dispensing from and restocking the remote dispensing systems are also given, as well as a method for indicating which item is to be dispensed from one of a plurality of bins. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a 35 USC 371 application of PCT/EP 2006/069086 filed on Nov. 30, 2006.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method and circuit arrangement for determining the rotor position of an electronically commutated motor (EC motor). Methods of this kind, which are required for a controlled run-up of EC motors from the standstill state with maximum moment, are basically known. In this connection, the detection of the rotor position is carried out either with the aid of rotation angle sensors or alternatively without such sensors, through the use of magnetic machine effects.
2. Description of the Prior Art
For machines with a magnetically asymmetrical or symmetrical rotor, DE 101 62 380 A has disclosed determining the position of the rotor in the standstill state of the machine. In this instance, the measurement is carried out using saturation effects in the rotor iron so that over a full rotation of the rotor, the stator phases are acted on cyclically by a number of current pulses that corresponds to twice the number of stator phases, which pulses are respectively offset from one another by the same angle. The rise times of the current pulses, which occur in accordance with the degree of saturation of the respective rotor section are then used to determine the rotor position in the standstill state of the motor. Such a method requires a large number of powerful current pulses for the measurement, which causes unwanted magnetic noise, movements of the motor shaft, and a delay in the starting of the motor.
In addition, the prior art (German patent application 102 005 007 995.4) already includes the proposal of determining the position of the rotor of an EC motor in two successive steps in that in order to ascertain the position of the d-axis, the stator of an EC motor with a magnetically asymmetrical rotor is initially excited with current pulses that do not result in saturation effects in the rotor, and in this case, measuring the magnitude of the current that occurs. Then a stator phase that can be associated with the d-axis of the rotor is acted on with current pulses, which produce a saturation of the iron in the rotor, in order to determine the north/south orientation of the rotor. In both measurement procedures, the potential is measured on the one hand, at the winding star point of the stator and on the other hand, at a summation point of the phase voltages generated by means of resistances and is used as a criterion for the magnetic concatenation between the stator and the rotor of the motor. To this end, the winding star point of the stator must be led out and made accessible, thus limiting the usability of the motor. In addition, the detection of potentials increases the circuitry complexity of the arrangement since an analog/digital conversion is required in the control unit. Because of the required magnitude and duration of the individual phase current supplies, the current in the stator windings is reversed during the measuring procedure in order to achieve a quasi-stationary state of the rotor. This results in a relatively long measurement duration.
It is also known to determine the position of the rotor without the use of rotation angle sensors after the motor is started, based on the induced revolving field voltage in the respective unpowered phases. This method, however, only permits a reliable conclusion to be drawn about the rotor position after the motor has reached a certain minimum speed.
SUMMARY AND ADVANTAGES OF THE INVENTION
The object of the present invention is to permit a rotor position detection that is operationally reliable and can be implemented without high circuitry complexity, which, even when the motor is at a standstill, quickly supplies a rotor position signal with a low stator current and permits acceleration of the motor from a standstill with a maximum moment. This is achieved by the characterizing features of the invention while significantly reducing the noise in the machine and the movements of the shaft during the determination of the rotor position.
The supply of current to the stator advantageously occurs so that, in both the time measurement with the reluctance effect and in the time measurement with the saturation effect, the stator phases are triggered with voltage pulses of the same magnitude, preferably the magnitude of the operating voltage. Limiting the duration of the voltage pulses assures that the current pulses achieved in the stator phases have the same respective magnitude in both the measurement with the reluctance effect and the time measurement with the saturation effect. In the time measurement with the reluctance effect, the magnitude of the current pulses must be set so that no saturation occurs in the rotor iron, whereas in the time measurement with the saturation effect, the magnitude of the current pulses must be set so that saturation does in fact occur in the rotor iron. In this way, within a shortened time and with a reduced supply of current to the stator, in a first step using magnetic asymmetry, the d-axis of the rotor is determined as the axis with the lowest main inductance and, in a second step using saturation, the correct-polarity orientation of the rotor is determined by establishing the polarity with the lower main inductance in this measuring step and, in accordance with the rotor position determined, a starting current supply of the motor is established.
It has turned out to be very advantageous if, in an additional step after the starting of the motor, the voltages that the revolving field induces in the stator are also measured. This makes it possible for an initial current feed of the stator, which is unfavorable for a maximum possible moment progression and results from a possible boundary position of the rotor at the sector boundary of two stator phases, to be identified by comparing the levels of the revolving field voltages and corrected by changing the commutation of the stator current feed. This measurement is continued during the operation of the motor in order to continuously monitor the current feed pattern. The method according to the present invention can thus be embodied in a particularly advantageous fashion if on the one hand, during the start of the motor, a control unit for the stator current feed is controlled by means of a counter for determining and evaluating the rise times of the phase currents and on the other hand, after the start of the motor, the control unit is controlled by means of a component for detecting the currents induced in the unsupplied phases of the stator and this control unit, immediately after the start of the motor, checks the chronological evaluation of the phase currents and if need be, takes corrective intervention steps in the sequence control.
With regard to the embodiment of a circuit arrangement according to the present invention for determining the rotor position of an EC motor with a magnetically asymmetrical rotor, it is suitable if the input of a counter designated for determining the rise times of the phase currents is connected to the output of a differential amplifier whose inputs are contacted on the one hand, by a signal that corresponds to a limit value of the phase current and on the other hand, by a signal that corresponds to the magnitude of the respective phase current measured; the magnitude of the phase currents is preferably determined by means of a low-impedance resistor that is situated in the sum electric circuit of an inverter for the phase currents. Such a circuit arrangement can be implemented with a low degree of complexity for components and low costs, particularly through the use of an ASIC component for the sequence control unit. On the other hand, the use of a microcontroller as a control unit eliminates the need for including a separate counter and permits the direct software control of the inverter for the supply of current to the stator phases.
BRIEF DESCRIPTION OF THE DRAWINGS
Other details and advantageous embodiments of the present invention ensue from the claims and from the description of an exemplary embodiment when taken with the drawings, in which:
FIG. 1 shows a circuit arrangement for carrying out the method according to the present invention,
FIG. 2 shows a sectional depiction of the stator and rotor arrangement of a three-phase, four-pole EC motor, and
FIG. 3 is a schematic depiction of the measured phase currents, on the one hand in the unsaturated state of the rotor iron and on the other hand through the use of saturation effects.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 , the reference numeral 10 denotes an EC motor (electronically commutated motor), having a three-phase stator 12 connected in a star, the stator phases U, V, W, and a four-pole, permanently excited rotor 14 . The motor is supplied with current in a known way via an inverter 16 in a full bridge circuit, which on the one hand, is connected to the plus pole 18 of a d.c. voltage source U and on the other hand, is connected with its star point to a ground connection 20 via a shunt 22 . A control unit 24 , which in the known construction of the inverter 16 is likewise embodied as a six-poled arrangement with six semiconductor switches, controls the inverter 16 via a control line 26 .
In accordance with the sum current I of the inverter 16 , the voltage drop at the shunt 22 is picked up at the connection point 28 and is supplied via an amplifier 30 to the non-inverting input of a comparator 32 . Via a line 34 , the inverting input of this comparator is supplied with a limit value signal predetermined by the control unit 24 in accordance with a predetermined sum current limit value I G1 or I G2 according to FIG. 3 . The output of the comparator 32 is connected to the input of a counter 36 , which at its output, supplies a counting signal to the control unit 24 in accordance with the rise time of the motor sum current I up to the predetermined limit value I G1 , I G2 . The output signal of the comparator 32 is picked up at a connecting point 40 between the comparator 32 and a counter 36 and is supplied via a line 42 directly to the control unit 24 in order to reset the counter 36 once the respective limit values I G1 , I G2 of the sum current I are reached. The starting of the counter 36 with the next current pulse according to FIG. 3 occurs by means of its supply line 44 .
The circuit arrangement show in FIG. 1 is completed by means of a device 46 for rotor position determination through detection of voltages U i that the rotating rotor 14 induces in the unpowered phases U, V, W of the stator 12 . To this end, the device 46 is connected to respective connections 50 , 52 , 54 of the phases U, V, W of the stator 12 and its output is connected to the control unit 24 via a line 48 .
FIG. 2 shows a section through the stator 12 and rotor 14 of a three-phase four-pole EC motor with a magnetically asymmetrical rotor 14 . In synchronous operation, a 120° block current feed of the stator phases U, V, W necessitates a commutation every 60°, thus making it possible to divide an electric rotation into six sectors with a two-phase current supply. The sectors are labeled with the numerals 1 through 6, the magnetic axes of the rotor 14 are labeled d′ and q′, with the magnetization being produced by means of two magnet segments 56 and 58 . The south pole of each of the magnet segments 56 and 58 is shown; the associated north poles are formed in the stator iron on a second horizontally extending d-axis. The design of the rotor 14 could, to the same effect, also be embodied with four magnet segments. The two q-axes each extend centrally between the d-axes.
On the left side, FIG. 3 shows the curve of the phase currents I u , I v , and I W in the standstill state of the machine in the unsaturated current supply range, each limited by the current ±I G1 . In the saturated range, the current ±I G2 limits the phase currents at which the measurement in the unsaturated current supply range has yielded the shortest rise time. In the exemplary embodiment, these are the currents I U and I w . In this case, via the inverter 16 , the control unit 24 at first positively powers one of the three phases and negatively powers a second one, then first times t 1 , t 2 , t 3 are measured from the beginning of the pulse to the reaching of the limit value I G1 , and the shortest of the three first times is established as a criterion for one of the sectors 1 through 3 and 4 through 6 in which the d-axis of the rotor 14 is presently situated. In this case, for the resulting flux vector, the following equations are true: in sector 1 : I W =−I U , in sector 2 : I W =−I V , and in sector 3 : I V =−I U . At the end of the three measurements, the lowest counter value and the associated sector number are contained with the flux vector in the memory of the counter 36 and are furnished to the control unit 24 as a criterion 38 for the course of the d-axis. This determines the orientation of the d-axis of the rotor 14 .
In a second measuring procedure, the two phases U and W with the shortest rise time t 1 , from the first measurement are again inversely powered with a limit value I G2 of the current raised to the saturation range; a rise time t 4 of the phases U−/W+, due to the lower saturation and the resulting shorter rise time t 4 of the current, is recognized as the correct phase position with regard to the north/south orientation of the d-axis. In accordance with this orientation of the rotor 14 , the control unit 24 then establishes a sequence control with the corresponding current supply to the phases U, V, W by means of the inverter 16 and the motor can be started with a maximum moment.
A difficulty in making the determination in the starting position of the rotor 14 can arise if the rotor is situated in a boundary position between two sectors. Such a boundary position between two sectors can, for example, occur due to the detent moment of the EC motor or due to other influences. In this case, in order to correct an unfavorable initial current supply, in an additional step after the starting of the motor 10 , the unfavorable initial current supply of the stator 12 resulting from a boundary position of the rotor 14 at the sector boundary of two stator phases can be identified by comparing the level of the revolving field currents and the stator current supply can be corrected by changing the commutation pattern. To this end, after the starting of the motor, the device 46 changes the current supply pattern originally established by the counter 36 based on the time measurements t 1 , t 2 , t 3 , by detecting and evaluating the voltages U i induced in the unpowered phases of the stator. Furthermore, due to the continuous detection of these induced voltages during operation of the motor 10 as well, a rotor position signal is continuously supplied to the control unit 24 via the line 48 , which signal then plays a dominant role in the determination of the current supply if the initial current supply has to be changed.
The method according to the present invention is consequently based on the advantageous combination of two or preferably three essentially known measuring methods. On the one hand, this constitutes the use of the reluctance effect due to the magnetic asymmetry of the rotor 14 with minimal main inductances in the region of the d-axes and maximal main inductances in the region of the q-axes of the rotor. On the other hand, the use of saturation effects in the iron and the higher supply of current to the rotor necessitated by this is only required for determining the correct-polarity north/south rotor position in the standstill state; the quicker current rise to the limit value I G2 , in the exemplary embodiment in the time t 4 , is detected with a positive powering of the phase V and a negative powering of the phase U. The quicker current rise in this instance is due to the more powerful saturation effect when the stator 12 and rotor 14 are situated opposite like poles.
By monitoring the revolving field current U i after the starting of the motor 10 , the current supply pattern of the stator 12 can be tested in any operating state and corrected as needed. The noise and movements of the motor shaft, which are caused particularly with the use of saturation effects in the motor, are minimized by measuring with fewer and significantly weaker current pulses in the measurement method according to the present invention. With a shortened measurement duration, this achieves the acceleration of the motor with a maximum moment.
The circuitry complexity for the measurement is reduced to a low-impedance measuring resistor 22 for the sum current I of the inverter 16 , an individual operational amplifier as the amplifier 30 , a sum current comparator 32 , a counter 36 , and the control unit 24 as a finite state machine for the sequence control. This can be implemented either in the form of an ASIC or a microcontroller. When using a microcontroller as the control unit 24 , the counter 36 is already contained in the microcontroller and the sequence control can be embodied in the form of software. The device 46 for determining the induced voltage is frequently already present in EC drive units that do not have rotation angle sensors so that it does not have any appreciable effect on the circuitry complexity.
The foregoing relates to the preferred exemplary embodiment of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | A method and circuit arrangement for determining position of the rotor of an electronically commutated motor, wherein the rotor has magnetic axes having different permeances. Voltage is applied to stator phases, and resultant phase currents are monitored for purpose of determining rotor position in the standstill state of the motor. First and second rise times of phase currents are determined until predetermined limit values are reached in unsaturated state. The assignment of a magnetic axis to a stator phase is determined from first rise times of the currents in unsaturated state of the rotor core, and the polarization of the rotor is determined from second rise times of currents upon energization with saturation effects. After run-up of the motor, initial energization of the stator can be determined comparing levels of the magnet wheel voltages and corrected by changing the commutation of stator energization. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority to and the benefit of U.S. Provisional Patent Application 61/065,108, filed Feb. 8, 2008, which is hereby incorporated.
FIELD
This application concerns methods and apparatus for use in industrial waste recovery operations such as recovery of non-consumed chemicals in industrial processes, with recovery of quick lime in a wood pulp process being an example.
BACKGROUND
In making paper and other pulp products, cellulosic fiber, such as for example wood, is chemically digested in a continuous or a batch process. Usually, the fiber is charged together with a cooking liquid such as a white liquor having certain desirable chemicals for dissolving a majority of the lignin contents of the wood. Pulp so formed is typically washed or rinsed, and separated from the cooking liquid. The filtrate from the rinse forms a weak black liquor.
As used herein, “black liquor” means the waste product that results from separating the pulp from the cooking liquid subsequent to digesting the cellulosic fiber. Black liquor is usually rich in valuable chemicals, some of which can be recovered to produce additional and/or cooking liquid for use in the digester. For example, black liquor can be concentrated by evaporating a major portion of its water contents in an evaporation plant and some of the chemicals can be recovered in the form of Na 2 CO 3 . The concentrated black liquor is combusted in a recovering furnace to produce desirable process steam and a smelt having certain desirable chemicals that can be dissolved in water to form a green liquor.
The Na 2 CO 3 (sodium carbonate) is used to produce NaOH (sodium hydroxide), an ingredient used to produce the cooking liquid, by treating the concentrated green liquor with burnt lime, also known as quick lime, (CaO). The causticizing reaction just described and used to produce the sodium hydroxide is shown in Equations 1 and 2.
CaO+H 2 O→+Ca(OH) 2 +Heat Equation 1
Na 2 CO 3 +Ca(OH) 2 →2NaOH+CaCO 3 Equation 2
An additional recovery process is usually applied to “close” the cycle and recover quick lime from the lime sludge (also known as lime mud), which includes CaCO 3 . NaOH and solutions with dissolved NaOH, such as aqueous NaOH, can also be recovered from the lime sludge. After rinsing, the lime sludge is heated in a lime kiln to evaporate any remaining water, and then heated further in a reburning process to recover the quick lime according to the stoichiometric reaction shown in Equation 3.
CaCO 3 +energy→CaO+CO 2 Equation 3
Many kilns used to recover quick lime from lime sludge are heated by a continuous heat source, such as by continuous combustion of natural gas. Fuel costs for kilns heated only by combustion of natural gas are high, and combustion of natural gas only usually leads to peak flame temperatures in excess of 2800° F., which undesirably forms oxides of nitrogen (NO N ). In addition, some chemicals in the cooking liquid and green liquor (and thus the lime sludge), as well as natural gas, contain sulfur. Consequently, the high combustion temperature of natural gas usually forms oxides of sulfur (SO x ) in addition to the NO N , which makes compliance with emissions requirements difficult.
SUMMARY
Methods for recovering lime from a manufacturing process are disclosed. Such methods include baking lime sludge in a kiln and controlling a flame temperature of a flame so that a temperature in a calcining zone of the kiln is above about 2250° F. to vaporize sodium contained in the lime sludge. Interaction of the vaporized sodium with SO x deters accumulation of one or both of CaCO 3 and CaSO 4 on one or more inner surfaces of the kiln.
A fluid fuel can provide a continuous ignition source for co-firing a pulverized solid fuel. The fluid fuel can be natural gas, and a flow rate of the natural gas can be between about 10 MCF and about 20 MCF. Petroleum coke can be co-fired with natural gas to produce the flame. In some embodiments, natural gas is continuously burned as a primary ignition source, and petroleum coke is injected into the primary ignition source from above.
The act of controlling the flame temperature can comprise one or more of selecting a volumetric flow rate of an oxidizer, selecting a volumetric flow rate of a fuel-supply inlet stream carrying entrained particles of petroleum coke, and selecting respective flow rates of petroleum coke and fluid fuel. A volumetric flow rate of a fuel-supply stream can be between about 550 CFM and about 850 CFM. A flow rate of petroleum coke can be between about 50 pounds per minute and about 60 pounds per minute.
Other methods of recovering lime are also disclosed. Such methods include rinsing a lime sludge with a rinse to generate a filtrate comprising dissolved NaOH and baking the rinsed lime sludge in a kiln exhausting at least some SO x . At least a portion of the SO x can be scrubbed from the exhaust in a scrubber at least partially charged with the filtrate comprising dissolved NaOH. Quick lime can be removed from the kiln.
Kilns for recovering lime are also disclosed. Some such kilns have an entrance region for receiving lime sludge, and define a calcining region disposed opposite the entrance region. A co-fired burner for burning pulverized solid fuel can be located in or near the calcining region. The co-fired burner can include a fluid-fuel injector for providing a continuous ignition source and an injector body positioned above the fluid-fuel injector for injecting a pulverized solid fuel downwardly into the continuous ignition source. As noted above, the pulverized solid fuel can be petroleum coke.
In some kilns, the fluid-fuel injector comprises one or more turning vanes for mixing a fluid fuel with an oxidizer. The injector body can comprise a nozzle for turning a stream of the solid fuel between about 15 degrees and about 25 degrees. Some injector bodies comprise a tube having an inner-diameter of about 4 inches. Petroleum coke can be injected by such an injector body. In at least some kilns, the calcining region is positioned below the co-fired burner.
Systems for recovering lime are also disclosed. Such systems include a lime sludge washer for rinsing a lime sludge with a rinse and producing a filtrate. A scrubber in fluid connection with the washer can receive the filtrate from the washer. The filtrate can comprise a solution of NaOH. A kiln for baking lime sludge can have an exhaust in fluid connection with the scrubber for exhausting kiln exhaust products at least partially through the scrubber. The scrubber can be configured to scrub SO x from the kiln exhaust products with the filtrate.
Kilns as disclosed herein can be used in such systems. For example, kilns having a co-fired burner can be used in such systems. Such co-fired burners can include a first injector for injecting natural gas for providing a continuous ignition source inside the kiln and a second injector positioned above the first injector comprising a nozzle for injecting a stream of petroleum coke into the continuous ignition source.
The foregoing and other features and advantages will become more apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an exemplary liquor cycle in a wood pulp manufacturing process.
FIG. 2 illustrates a schematic of an exemplary apparatus for recovery of quick lime.
FIG. 3 illustrates a schematic of an exemplary co-fired burner that can be used in an apparatus for industrial waste recovery processes, such as the recovery of quicklime.
DETAILED DESCRIPTION
The following describes embodiments of methods and apparatus for recovering materials from industrial waste, such as recovering lime from a pulp process.
The following makes reference to the accompanying drawings which form a part hereof, wherein like numerals designate like parts throughout. The drawings illustrate specific embodiments, but other embodiments may be formed and structural changes may be made without departing from the intended scope of this disclosure. Directions and references (e.g., up, down, top, bottom, left, right, rearward, forward, heelward, etc.) may be used to facilitate discussion of the drawings but are not intended to be limiting. For example, certain terms may be used such as “up,” “down,”, “upper,” “lower,” “horizontal,” “vertical,” “left,” “right,” and the like. These terms are used, where applicable, to provide some clarity of description when dealing with relative relationships, particularly with respect to the illustrated embodiments. Such terms are not, however, intended to imply absolute relationships, positions, and/or orientations. For example, with respect to an object, an “upper” surface can become a “lower” surface simply by turning the object over. Nevertheless, it is still the same surface, and the object remains the same.
Accordingly, the following detailed description shall not be construed in a limiting sense.
Exemplary Liquor Cycle
FIG. 1 illustrates an exemplary liquor cycle in an exemplary wood pulp manufacturing process. In the cycle shown in FIG. 1 , wood chips 301 are combined with a cooking liquid that includes a mixture of white liquor 303 and black liquor 310 in a digester 302 . Gases from the digester 302 are transferred (e.g., by a pressure differential) to a blow tank 304 where they are condensed and discarded as a waste product 305 to a suitable waste site 315 .
The mixture of digested chips and cooking liquid is moved to a washer apparatus 306 where the pulp 307 is rinsed, such as for example by water, and separated from the mixture. The filtrate 308 is moved to a weak black liquor storage 309 . A portion 310 of the weak black liquor can be used to at least partially recharge the digester 302 .
The remaining weak black liquor 311 is concentrated by evaporating excess volatiles, including water, in one or more evaporators 312 . The gaseous products of evaporation 313 are blown off and condensed to be disposed of in the suitable waste site 315 . The black liquor so concentrated is stored in a strong black liquor storage apparatus 314 before entering a recovering furnace 316 where the black liquor is baked to form smelt 317 .
The smelt 317 is dissolved in a dissolving tank 318 and the resulting solution, green liquor, is transferred to a green liquor clarifier 319 . Dregs 320 are filtered out and transferred to a dregs washer 324 where the precipitated dregs are washed, for example, with water 323 . The resulting filtrate 327 can be stored in a weak liquor storage 328 and recombined with the smelt 317 in the dissolving tank 318 . The washed dregs 325 can be disposed of and transferred to a suitable waste site 326 .
The green liquor filtrate from the green liquor clarifier 319 can be stored in a green liquor storage 140 and/or transferred to a slaker 150 . In the slaker 150 , the green liquor is combined with lime 101 . By combining the green liquor and the lime 101 , the reaction of Equation 1 occurs. The reaction of Equation 2 can also be carried out in the slaker 150 , but as the reaction drives toward completion, it slows. The resulting mixture containing NaOH and CaCO 3 can then be transferred to the causticizer 160 after removing the grits for disposal. While in the slaker 150 and the causticizer 160 , the mixture can be kept well agitated to assist completion of the reaction and to prevent precipitation of the CaCO 3 . The causticizer 160 can be used to allow more time for the reaction of Equation 2 to complete.
The products of Equation 2, including precipitated CaCO 3 and NaOH in solution, can be transferred to the white liquor clarifier 321 where the white liquor can be filtered and transferred to the white liquor storage 322 . The clarifier 321 provides residence time and slow movement to allow the CaCO 3 to settle to the bottom of the clarifier. The corresponding lime mud (CaCO 3 ) 327 can be collected from the bottom of the clarifier and transferred to the lime recovery cycle 200 , which can be referred to as the “Miller Process.”
In the lime recovery cycle 200 , the lime sludge 327 can be transferred to the lime mud washer 113 where the lime sludge 327 can be rinsed with a rinse 115 capable of dissolving NaOH in solution, e.g., water for an aqueous solution of NaOH. Filtrate 109 from the lime mud washer 113 containing a solution of NaOH, such as aqueous NaOH, can be transferred to a weak liquor storage 117 . A solution 119 containing sodium ion, such as for example stored weak liquor (e.g., the filtrate 109 ) can be fed to a scrubber 108 for scrubbing gas products 102 emitted from the kiln 100 . Such scrubbing is described in more detail below.
The washed lime sludge 116 can be transferred to a lime sludge thickener 114 (referred to as a “lime mud precoat filter” in FIG. 2 and the corresponding description below) for thickening the lime mud 116 by, for example, vacuum removal of rinse solution through a filtration assembly. Additional filtrate 109 collected from the lime sludge thickener 114 can be transferred to the weak liquor storage 117 . As described in further detail below, a lime mud thickener 114 can be located at an entrance of a kiln 100 in some embodiments. Once sufficiently thickened, the lime sludge 84 , (e.g., primarily CaCO 3 ) can be transferred to a lime kiln 100 (or a baking region thereof, such as a calcining region) and baked at a sufficiently elevated temperature to cause the CaCO 3 to undergo the reaction of Equation 3. The resulting CaO (lime) 101 can then be removed from the lime kiln and readied for transfer to the slaker 150 .
The lime kiln gases 102 , for example from combustion of the fuel used to heat the lime kiln 100 , together with the CO 2 from the reaction of Equation 3, desirably are fed through the scrubber 108 . The scrubbed kiln gases 120 can then be emitted to the environment 121 , e.g., the atmosphere.
Exemplary Embodiment of an Apparatus for a Lime Recovery Process
FIG. 2 illustrates a schematic of one embodiment of an apparatus 1 for recovering lime in an industrial process, such as a wood pulp manufacturing process. The apparatus 1 shown in FIG. 2 implements at least portions of the lime recovery cycle 200 described above and illustrated in FIG. 1 .
In the apparatus shown in FIG. 2 , the lime mud precoat filter 114 removes solids from the washed lime sludge 116 (see FIG. 1 ) and deposits wet lime sludge 84 on a kiln feed conveyor 92 configured to deliver the wet lime sludge 84 to the entrance 61 to the kiln 100 . Preferably, the filter 114 is configured to strain precipitated CaCO 3 from a solution having dissolved NaOH, such as a solution resulting from rinsing the lime sludge with water.
Typically, the rinse solution added to the lime mud precoat filter 114 can be controlled to reduce the likelihood of any remaining sodium from being entrained in the thickened lime sludge 84 . With respect to the exemplary lime mud precoat filter 114 , the rinse solution can be controlled (e.g., flow rate, NaOH concentration) to maintain the sodium entrained in the thickened lime sludge 84 at a sodium-to-sulfur molar ratio of about 2:1 with respect to the sulfur in the gas products 102 .
In the exemplary kiln 100 , the co-fired kiln burner 2 (also see FIG. 3 ) is disposed at an end opposite the entrance 61 to the kiln 100 . In one embodiment, after the conveyor 92 deposits a thickened lime sludge 84 into the entrance 61 of the kiln 100 , the thickened lime sludge moves countercurrent to a flow of gas products 102 (e.g., carbon dioxide, CO 2 , various oxides of nitrogen, NO and various oxides of sulfur, SO x , arising as, for example, products of combustion, evaporated wash and reburned lime sludge) toward the end having the co-fired burner 2 as the kiln 100 rotates about a longitudinal axis of the kiln. In this exemplary embodiment, the kiln is sloped downwardly from the entrance 61 to the end having the co-fired burner such that the lime “rolls” in a cascading fashion within the kiln. Although not a feature of all kilns (e.g., kilns having a lesser slope from the entrance to the exit), the exemplary kiln includes an internal dam for retaining the lime sludge 84 within the kiln for a longer period of time as compared to a kiln without the dam and having the same slope, increasing the time available for the reaction of equation 3 to complete.
The heated lime sludge 80 ( FIG. 3 ) undergoes the reaction of Equation 3, e.g., reburning. At the entrance 61 to the lime kiln 100 , the temperature can range, for example, from about 450° F. to about 650° F. At the end with the burner 2 , the temperature can range, for example, from about 1750° F. to about 1950° F.
After reburning, recovered lime 101 can be deposited in a lime crusher 83 in preparation for introduction into the slaker 150 (see FIG. 1 ).
A primary air supply for the kiln 100 enters an air intake 79 in fluid connection with a primary blower 78 . The primary blower 78 provides sufficient head to deliver a primary air supply to the kiln 100 , such as between about 500 cubic feet per minute (CFM) and about 1000 CFM. A damper 76 , such as a throttle valve, can be used to control a flow rate of the primary air supply. The throttle valve can be, for example, a butterfly valve. A fluid conduit 74 conveys the air supply from the blower 78 to the kiln 100 , and can incorporate a flexible segment 75 for accommodating vibration and various tolerances in the assembly 1 .
Although not necessary for implementing the Miller Process, the co-fired burner 2 shown in FIG. 2 can receive two fuels, for example a pulverized solid fuel (such as pulverized petroleum coke) and a fuel for providing a continuous ignition source (such as natural gas) for maintaining ignition of the pulverized solid fuel. A blower 28 can provide sufficient head to an airstream for entraining a pulverized solid fuel and injecting the entrained fuel in to the burner 2 . In some embodiments, the blower 28 delivers between about 550 CFM to about 850 CFM through a pipe with an approximately six-inch inner diameter. Pulverized solid fuel can be delivered from a pulverized solid fuel storage bin 26 by a pipe 27 , such as a duct, for conveying the solid fuel to the entrainment stream conveyed by the fluid connection 25 . A pipe 23 carries the entrained solid fuel stream 22 (see FIG. 3 ) to the burner 2 .
In the illustrated embodiment, a plenum 90 collects gas products 102 from the lime kiln exhaust, including products of combustion from the co-fired burner 2 and any products from reburning the lime sludge 84 . A stream of lime kiln exhaust gases enters an induced-draft fan 104 used to draw exhaust from the lime kiln 100 . A fluid conduit 106 between the outlet side of the induced-draft fan 104 and the scrubber 108 carries the gas products 102 to the scrubber 108 .
Some representative scrubbers are gas atomized (e.g., high pressure drop) Venturi scrubbers. The scrubber 108 can be a caustic scrubber. Many Venturi scrubbers have a sudden expansion at the Venturi inlet (e.g., from the inlet duct to the scrubber) into a larger diameter convergent-divergent “cone,” or nozzle. Liquid for scrubbing gas products 102 (conventionally water, but in the exemplary embodiment, a solution 119 , such as the filtrate 109 ) can be introduced to the scrubber (e.g., at or near the throat of the Venturi) for mixing with the gas products 102 and washing the walls of any buildup that may occur. For example, the scrubber 108 can be supplied with the solution 119 containing sodium ion from the weak liquor storage 117 , as in the Miller Process. As with other Venturis, Venturi action, e.g., mixing, takes place near the throat.
For example, the liquid 102 (which can be recycled as indicated by FIG. 2 ) can be delivered to the converging portion of the Venturi, where the kiln exhaust from the conduit 106 accelerates. The speed of the exhaust can approach, under some conditions, about 100,000 ft/min through the throat. At such high velocities, the stream of gas products 102 can atomize the injected scrubber liquid (which can later be separated from the gas stream in the separator 110 , as described below). A pressure drop across the throat of the Venturi can be used as a measure of scrubbing efficiency.
The small droplets can interact (e.g., by way of increased surface area) with the gas products 102 . Such interaction can remove particulate, and can also place chemicals, such as NaOH, that have been added to the liquid, e.g., the solution 119 , in close contact with components of the exhaust gas, such as SO x .
A slurry resulting from such scrubbing, particularly with a Venturi scrubber, can move at a relatively high-speed (“high-speed slurry”), and can be injected in an impinging stream into a flooded tank (e.g., an “elbow tank”). Such a flooded tank is shown near the base of the scrubber shown in FIG. 2 . The high-speed slurry can subsequently be injected into a separator vessel, such as the separator 110 , where solid particulate in the slurry can be separated from liquid, for example, by way of a cyclonic separation process.
After passing through the scrubber 108 and a separator 110 for removing condensates, the scrubbed exhaust 120 can have a lower concentration of SO x than the kiln exhaust 102 . In some instances, sufficient SO x can be removed to allow the scrubbed exhaust 120 to be emitted to the environment, most typically the atmosphere, and still meet environmental regulations.
Supplying the scrubber with solution from the liquor storage 117 can cause the amount of filtrate 109 to be at least partially proportional to the amount of lime sludge being processed and substantially proportional to a rate at which SO x is produced in the kiln 100 . Consequently, available solution 119 from the liquor storage 117 can be in part proportional to a rate of lime recovery and a rate of SO x production, to the extent the filtrate 109 from the liquor storage 117 is used to provide the solution 119 , rather than using additional (e.g., make-up) water, as is common in the prior scrubbing art. Because the solution 119 is a product of the lime recovery process, using this solution for charging the scrubber 108 can reduce costs, water consumption and waste.
Passing the kiln gases 102 through the scrubber 108 , as shown in the recovery cycle 200 (see FIG. 1 ), provides an efficient and cost effective method of removing excess SO x from the kiln gases 102 . Particularly valuable is that the amount of solution 119 having sodium available for charging the scrubber 108 is at least partially proportionate to the amount of reburnt lime sludge and the rate of SO x production. Thus, the scrubbing portion of the recovery cycle 200 can largely be performed without significant addition of material, thereby saving on material costs. Of course, the scrubber 108 can also be charged by an external source of sodium for scrubbing the excess SO x from the kiln gases 102 , if desired.
Exemplary Co-Fired Burner
FIG. 3 illustrates an exemplary co-fired kiln burner 2 that can be used to heat a kiln, such as the kiln 100 . The exemplary burner 2 is configured for co-fired combustion, such as combustion of a fuel capable of continuous combustion (e.g., natural gas) and combustion of a second fuel, such as a fuel having a high combustion temperature (e.g., a pulverized solid fuel, such as petroleum coke). As shown in FIG. 3 , the burner 2 comprises a first fuel injector 34 for providing a continuous ignition source for igniting a high-combustion-temperature fuel from a second injector (such as, for example, the nozzle 24 ). The burner illustrated in FIG. 3 , a frame 10 supports injector body 20 and the main burner 30 , which extend through the firewall 70 isolating the firing end of the kiln 100 from the environment. The exemplary firewall partially forms a firing end hood disposed about the first and second injectors. An exemplary injector body 20 is a pipe with an approximately four-inch inner diameter in fluid connection with the pipe 23 ( FIG. 2 ) carrying entrained pulverized solid fuel.
A typical ignition temperature of a pulverized solid fuel can be about 1800° F. As noted, some embodiments of co-fired burners are natural gas co-fired burners that continuously burn natural gas for igniting the solid fuel.
An inlet stream 22 of solid fuel, such as a stream of air with entrained particles of petroleum coke, can enter the body 20 at a first end and be discharged at a second end having an injector nozzle 24 . In some embodiments, the inlet stream 22 delivers between about 550 CFM and about 850 CFM of air and entrained fuel, carrying between about 50 pounds per minute and about 60 pounds per minute (lbs/min) of entrained fuel, such as pulverized petroleum coke.
The nozzle 24 desirably can be configured as a pulverized solid-fuel injector nozzle, such as a nozzle for injecting pulverized petroleum coke into a continuous ignition source from above. In the illustrated embodiment, the nozzle 24 injects pulverized petroleum coke at an angle 8 between about 15 degrees and about 25 degrees below a horizontal line 59 . In other words, the illustrated nozzle 24 turns the inlet stream 22 by about 15 degrees and about 25 degrees in the direction of gravity. In at least one embodiment, the nozzle is formed by approximately cutting in half a 45-degree bend configured for a four inch inner-diameter pipe to form a pipe fitting having about a 22.5-degree bend.
As noted above, a main burner 30 can provide a continuous ignition source for igniting a high-combustion-temperature fuel. An inlet stream of fluid fuel 32 (e.g., gaseous natural gas) enters the burner 30 . In the illustrated embodiment, the main burner 30 is configured as a natural gas burner for continuously burning between about 10,000 cubic feet per hour (10 MCF) and about 75,000 cubic feet per hour (75 MCF). The illustrated fuel injector 34 is a natural gas injector having a plurality of turning vanes (not shown) to enhance mixing of the fuel stream 32 with an oxidizer, such as, for example, air.
In the embodiment shown in FIG. 3 , the injection stream 40 of a pulverized solid fuel mixes with the continuous ignition source 50 . In the case of a natural gas burner, the ignition source 50 is a continuous flame produced by burning the injection stream of the natural gas. Individual particles 42 of a pulverized fuel burn when mixed with the ignition source 50 . A resulting flame 52 can be generally characterized as less intense and at a lower temperature than a flame resulting from burning the fluid fuel 32 alone. A desirable flame reduces erosion of refractory materials within the kiln 100 and also reduces the tendency of the kiln exhaust 102 to entrain CaCO 3 dust from the lime sludge 80 . Mixing of the solid fuel particles 42 with the continuous ignition source 50 can be enhanced by the presence of turning vanes in the vicinity of the nozzle 24 inside the kiln.
In the illustrated embodiment, heated lime sludge 80 passes beneath the flame 52 within the kiln 100 . The flame 52 can be controlled (e.g., temperature) by adjusting the damper 76 (see FIG. 2 ) to control the primary air supply, by adjusting the blower 28 to control the air volume of the fluid supply inlet stream 22 , and/or by adjusting fuel flow rates. Desirably, the resulting flame 52 is a short bushy flame that “licks” the bed of the lime sludge 80 (the flame contacts the surface of the lime sludge). Co-fired burners as described herein typically provide better control of a flame than a burner configured to burn only natural gas.
By placing the nozzle 24 above the fuel injector 34 as shown by FIG. 3 , the flame can be better controlled to achieve a particular intensity, e.g., temperature, flowrate, and degree of interaction with or licking of the bed of lime sludge 80 . In addition, co-fired burners typically provide better control of the flame 52 in a calcining zone than a single fuel burner, e.g., a natural gas burner. For example, co-fired flames are typically shorter and bushier compared to a single-fuel (e.g., natural gas) flame, which is typically also more intense. Consequently, a co-fired burner can provide better control of temperature and heat intensity throughout a larger portion of a calcining zone than a single fuel, natural gas burner. In certain embodiments, the flame from a co-fired burner is controlled to have a temperature ranging between about 1750° F. to about 1950° F. for the lime 101 as it exits the kiln 100 .
Combustion in a co-fired burner 2 , together with reburning lime sludge 80 , produces gaseous products 102 . As noted above, these typically include carbon dioxide, various oxides of sulfur (SO x ) and various oxides of nitrogen (NO x ). However, by maintaining the flame temperature below about 2800° F., the temperature at the firing end of the kiln (e.g., at the end with the burner 2 ) can be maintained within a range to sufficiently reduce emissions of NO to meet many statutory emissions requirements. In certain embodiments, a temperature at a firing end of the kiln 100 can be maintained in the range between about 1750° F. and about 2500° F., and between about 1750° F. and about 1950° F. in certain embodiments. In addition, lower flame temperatures as delivered by co-fired burners can further reduce SO x concentrations in the gas products 102 .
In reburning lime sludge 80 , however, CaCO 3 and calcium sulfate (CaSO 4 ) tend to accumulate on interior walls of the kiln 100 , degrading kiln performance. In addition, CaCO 3 and CaSO 4 tend to accumulate, on the blower of the induced draft fan 104 , causing the blower to drift out of balance and degrade in performance. In addition, high concentrations of SO x generally increase the accumulation of CaCO 3 and CaSO 4 on the kiln walls and blower.
In a co-fired burner fueled in part by petroleum coke, the resulting flame can be maintained to provide a peak temperature in the calcining zone of the kiln 100 sufficient to intentionally vaporize the sodium contained in lime sludge 80 . In particular embodiments, the flame temperature is maintained to provide a peak temperature in the calcining zone of the kiln in the range of above about 2250° F. to about 2500° F. Such vaporized sodium can in turn chemically react with high concentrations of SO x in the gas products 102 . Interaction of the sodium with the SO x can reduce, and in some cases eliminate, accumulation of CaCO 3 and CaSO 4 inside the kiln and maintain performance of kiln refractory and the induced draft fan 104 . Before emitting the kiln gases 102 to the environment, the gases can be passed through a scrubber, such as the scrubber 108 previously described, to remove at least some of the excess SO x and comply with emissions requirements.
In addition to reducing excess emissions and accumulation of CaCO 3 and CaSO 4 , a co-fired burner can significantly reduce operating costs of recovering useful chemicals from industrial waste. Typically, petroleum coke is less expensive than natural gas when the cost of each is normalized according to its respective available energy from combustion. In a working embodiment of the lime recovery process, natural gas consumption dropped from about 75 MCF when using a natural gas only burner to between about 10 and about 20 MCF using a co-fired burner configured to burn petroleum coke using a natural gas flame as the continuous ignition source. This large drop in natural gas usage and corresponding costs can more than offset incremental additional costs of petroleum coke.
In view of the many possible embodiments to which the principles of the disclosed innovations may be applied, it should be recognized that the illustrated embodiments are only examples and should not be taken as limiting the scope of the following claims. I therefore claim as my invention all possible embodiments and their equivalents that come within the scope of these claims. | This application concerns methods and apparatus for use in industrial waste recovery operations such as recovery of non-consumed chemicals in industrial processes, with recovery of quick lime in a wood pulp process being an example. In some embodiments, methods comprise baking lime sludge in a kiln and controlling a temperature in a calcining zone of the kiln to be above about 2250° F. to vaporize sodium contained in the lime sludge. Interaction of the vaporized sodium with SO x can deter accumulation of one or both of CaCO 3 and CaSO 4 on one or more inner surfaces of the kiln. In some embodiments, lime sludge can be rinsed to generate a filtrate comprising dissolved NaOH, and the filtrate can charge a scrubber for removing SO x from an exhaust from the kiln. Embodiments of co-fired burners for heating such kilns by burning petroleum coke and natural gas are also disclosed. | 2 |
CROSS-REFERENCE TO RELATED PATENT APPLICATION
This application is based on and claims priority from Korean Patent Application No. 10-2008-0012208, filed on Feb. 11, 2008, the disclosure of which is incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
1. Technical Field
The present disclosure relates to a level shifting circuit, and more particularly, to a level shifting circuit capable of maintaining a duty rate irrespective of a voltage change and capable of fixing its output to a specific voltage level.
2. Discussion of the Related Art
Mobile devices guarantee proper performance during an extended period of time using a limited battery. A variety of methods have been introduced in order to guarantee such performance one of which is to use different voltages in different block units. In this case, a high voltage is applied to a block requiring a high performance, and a low voltage is applied to a block requiring a low performance.
Since blocks use different voltages, a leakage current increases due to a voltage difference between interfaces of different blocks or when a problem occurs in a circuit operation.
To address these problems, a level shifter is used. The level shifter changes a level of a received voltage. The level shifter is disposed between blocks that use different voltages, thereby preventing the leakage current or circuit malfunction that may occur in blocks using different voltages.
SUMMARY OF THE INVENTION
Embodiments of the present invention seek to provide a level shifting circuit capable of maintaining a duty rate irrespective of a voltage change.
Further, embodiments of the present invention seek to provide a level shifting circuit that fixes an output to a specific voltage level for a specific mode.
Furthermore, embodiments of the present invention seek to provide a level shifting circuit that blocks parts of signal transfer units from an operation voltage or a ground for a specific mode.
A level shifting circuit, according to an exemplary embodiment of the present invention, comprises a first level shifting unit comprising a plurality of signal transfer units; a first operation control unit inactivating some of signal transfer units of the first level shifting unit in response to a clamping signal; a second level shifting unit connected in parallel to the first level shifting unit and comprising a plurality of signal transfer units; a second operation control unit inactivating some of signal transfer units of the second level shifting unit in response to the clamping signal; a signal output unit connected to output ends of the first and second level shifting units; and a clamping unit fixing the output ends of the first and second level shifting units to a predetermined voltage level in response to the clamping signal.
The first and second operation control units may connect some of the signal transfer units of the first and second level shifting units to ground, or to a first voltage or to a second voltage in response to a level of the clamping signal.
Each of the first and second operation control units may comprise a gate receiving the clamping signal; a first end connected to a signal transfer unit; and a second end connected to the ground, the first voltage, or the second voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the present invention will become apparent by reference to the following detailed description taken in conjunction with the attached drawings, wherein:
FIG. 1 is a block diagram of a level shifting circuit according to an exemplary embodiment of the present invention;
FIG. 2 is a circuit diagram of the level shifting circuit shown in FIG. 1 according to an exemplary embodiment of the present invention;
FIG. 3 is a circuit diagram of the level shifting circuit shown in FIG. 1 according to an exemplary embodiment of the present invention; and
FIG. 4 is a circuit diagram of a level shifting circuit according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements across various figures.
FIG. 1 is a block diagram of a level shifting circuit according to an exemplary embodiment of the present invention. Referring to FIG. 1 , the level shifting circuit comprises a first level shifting unit 110 , a first operation control unit 130 , a second level shifting unit 120 , a second operation control unit 140 , a signal output unit 190 , and a clamping unit 170 .
The first level shifting unit 110 and the second level shifting unit 120 comprises a plurality of signal transfer units that transit-delay a signal. For example, each of the first level shifting unit 110 and the second level shifting unit 120 may comprise four signal transfer units. The first level shifting unit 110 and the second level shifting unit 120 receive a logic signal input through IN. Each of the first operation control unit 130 and the second operation control unit 140 is connected to the first level shifting unit 110 and the second level shifting unit 120 , respectively, so that each of the first operation control unit 130 and the second operation control unit 140 inactivates some of the signal transfer units.
Each signal transfer unit comprises a plurality of signal transfer stages. When a signal input into each signal transfer unit transits from a logic high level to a logic low level, and from a logic low level to a logic high level, the signal passes through different signal transfer stages. Therefore, a transition delay time of the first level shifting unit 110 and the second level shifting unit 120 , when the signal transits from a logic high level to a logic low level, and when the signal transits from a logic low level to a logic high level are different from each other.
When the voltage level supplied to the signal transfer unit changes, the transition delay time of the signal transfer stages included in the signal transfer unit changes so that the transition delay time of the first level shifting unit 110 and the second level shifting unit 120 , when the signal transits from a logic high level to a logic low level may change, and when the signal transits from a logic low level to a logic high level may change.
In the present embodiment, although levels of supplied operation voltages VDDA and VDDB change, a signal transfer path is selected so that the transition delay time of the first level shifting unit 110 and the second level shifting unit 120 when the signal transits from the logic high level to the logic low level, and when the signal transits from the logic low level to the logic high level change by the same amount of time. Therefore, a duty rate of output signals of the first level shifting unit 110 and the second level shifting unit 120 may not change.
Referring to FIG. 1 , the first level shifting unit 110 and the second level shifting unit 120 are connected in parallel. An average signal of output signals of the first level shifting unit 110 and the second level shifting unit 120 is output to output ends of the first level shifting unit 110 and the second level shifting unit 120 . The signal transfer path is selected so that the transition delay time of the average signal when the signal transits from a logic high level to a logic low level, and the transition delay time of the average signal when the signal transits from a logic low level to a logic high level change by the same amount of time.
The signal output unit 190 is connected to the output ends of the first level shifting unit 110 and the second level shifting unit 120 , transit-delays the average signal of the output ends, and generates an output signal OUT.
The clamping unit 170 fixes the output ends of the first level shifting unit 110 and the second level shifting unit 120 to a previously determined voltage level in response to a clamping signal CLAMP. Although the previously determined voltage level is the second voltage VDDB in an exemplary embodiment, it may be another voltage level.
The first operation control unit 130 inactivates some of the signal transfer units 112 , 114 , 116 , and 118 of the first level shifting unit 110 in response to the clamping signal CLAMP. The second operation control unit 140 inactivates some of the signal transfer units 122 , 124 , 126 , and 128 of the second level shifting unit 120 in response to the clamping signal CLAMP. To this end, some of the signal transfer units 112 , 114 , 116 , 118 , 122 , 124 , 126 , and 128 are blocked from ground, so that some signal transfer units can be inactivated.
For example, a first sub control unit 132 is connected between the second signal transfer unit 114 and ground, so that the second transfer unit 114 is connected to ground or is blocked from ground by the first sub control unit 132 . Likewise, the second through fifth sub control units 134 , 142 , 144 , and 146 connect the fourth, fifth, seventh, and eighth signal transfer units 118 , 122 , 126 , and 128 , respectively, to ground or are blocked from ground.
FIG. 2 is a circuit diagram of the level shifting circuit shown in FIG. 1 according to an exemplary embodiment of the present invention. Referring to FIG. 2 , the clamping unit 170 may comprise a transistor PX 0 . For example, the transistor PX 0 may comprise a gate receiving the clamping signal CLAMP, a first end connected to the second voltage VDDB, and a second end connected to an output end of the first level shifting unit 110 and the second level shifting unit 120 . The first and second ends may be a source and drain, respectively. Alternatively, the first and second ends may be a drain and source, respectively.
When the clamping signal CLAMP has a logic low level, the transistor PX 0 is turned on so that the output ends of the first level shifting unit 110 and the second level shifting unit 120 are fixed to the second voltage VDDB irrespective of the average output signal of the first level shifting unit 110 and the second level shifting unit 120 . However, when the clamping signal has a logic high level, the transistor PX 0 is turned off so that the average signal of the output signals of the first level shifting unit 110 and the second level shifting unit 120 is output to the output ends of the first level shifting unit 110 and the second level shifting unit 120 .
Each sub control unit 132 , 134 , 142 , 144 , and 146 may comprise respective transistors NX 2 through NX 6 . For example, the transistor NX 2 may comprise a gate receiving the clamping signal CLAMP, a first end connected to the signal transfer unit 114 , and a second end connected to ground.
When the clamping signal CLAMP has a logic high level, the transistor NX 2 is turned on so that the signal transfer unit 114 is connected to ground and performs a signal transit delay operation. However, when the clamping signal CLAMP has a logic low level, the transistor NX 2 is turned off and the signal transfer unit 114 is blocked from ground and does not operate. As such, a logic level of the clamping signal CLAMP is adjusted in order to determine whether to operate the signal transfer unit 114 . If it is not necessary to operate the signal transfer unit 114 , a leakage current of the signal transfer unit 114 can be prevented.
The first through fourth signal transfer units 112 , 114 , 116 , and 118 included in the first level shifting unit 110 are used to transit-delay a signal, and may be inverters or differential amplifiers. For example, the first, third, and fourth signal transfer units 112 , 116 , and 118 may be inverters, and the second signal transfer unit 114 may be a differential amplifier. The fourth signal transfer unit 118 may perform a pull-up/pull-down function. Likewise, for example, the sixth through eighth signal transfer units 124 , 126 , and 128 may be inverters, and the fifth signal transfer unit 112 may be a differential amplifier. The seventh signal transfer unit 126 may perform the pull-up/pull-down function. Each signal transfer unit may be a signal transit delay unit other than an inverter and a differential amplifier.
Each signal transfer unit comprises a plurality of signal transfer stages. For example, the first signal transfer unit 112 may comprise a PMOS transistor P 10 and an NMOS transistor N 10 . When an input signal IN transits from a logic high level to a logic low level, the input signal IN passes through the PMOS transistor P 10 . When the input signal IN transits from a logic low level to a logic high level, the input signal IN passes through the NMOS transistor N 10 .
A pass time (transit delay time) of the PMOS transistor P 10 and the NMOS transistor N 10 changes according to a level of the first voltage VDDA supplied to the first signal transfer unit 112 . A gate-source voltage of the PMOS transistor P 10 and the NMOS transistor N 10 changes according to the level of the first voltage VDDA. When the gate-source voltage is high, the pass time of the PMOS transistor P 10 and the NMOS transistor N 10 decreases, whereas when the gate-source voltage is low, the pass time of the PMOS transistor P 10 and the NMOS transistor N 10 increases.
A transit delay time of the first signal transfer unit 112 changes according to the logic level of the input signal IN and the level of the first voltage VDDA. Likewise, a transit delay time of the signal transfer units 114 , 116 , 118 , 122 , 124 , 126 , and 128 changes according to the logic level of the input signal IN and the level of the supplied voltages VDDA and VDDB, and thus a transit delay time of the first and second level shifting units 110 and 120 changes.
In an embodiment of the present invention, although levels of supplied operation voltages VDDA and VDDB change, transistors are selected wherein the transition delay time of the first level shifting unit 110 and the second level shifting unit 120 when the signal transits from a logic high level to a logic low level, and when the signal transits from a logic low level to a logic high level change by the same amount of time.
Hereinafter, an operation where the first voltage VDDA is lower than the second voltage VDDB will now be described.
When the input signal IN transits from a first voltage VDDA level (logic high level) to a ground voltage level (logic low level), the transistors P 10 , N 20 , and N 21 of the first level shifting unit 110 and transistors P 31 , N 41 , and P 43 of the second level shifting unit 120 are turned on. Therefore, the input signal IN passes through the transistors P 10 , N 20 , and P 21 of the first level shifting unit 110 , and passes through the transistors P 31 , N 41 , and P 43 of the second level shifting unit 120 .
In this case, since the first voltage VDDA is lower than the second voltage VDDB, the gate-source voltage of the transistor P 10 is lower than that of the transistor P 21 . Therefore, a pass time of the transistor P 10 is longer than that of the transistor P 21 . Likewise, the pass time of the transistor N 20 included in the first level shifting unit 110 is longer than that of the transistor P 21 . The pass time of the transistors P 31 and N 41 included in the second level shifting unit 120 is long and the pass time of the transistor P 43 is short. Hereinafter, a long pass time of a transistor is indicated by “L”, and a short pass time is indicated by “S”.
Therefore, the total pass time of the first level shifting unit 110 is “L(P 10 )+L(N 20 )+S(P 21 )=2L1S”. The total pass time of the second level shifting unit 120 is “L(P 31 )+L(N 41 )+S(P 43 )=2L1S”. Thus, an average pass time of the first and second level shifting units 110 and 120 is “2L1S”.
When the input signal IN transitions from a ground voltage level (logic low level) to a logic high level (first voltage VDDA level), the transistors N 10 , P 11 , and N 21 of the first level shifting unit 110 and transistors P 40 , P 41 , and N 43 of the second level shifting unit 120 are turned on. Therefore, the input signal IN passes through the transistors N 10 , P 11 , and N 21 of the first level shifting unit 110 , and passes through the transistors P 40 , P 41 , and N 43 of the second level shifting unit 120 .
In this case, since the first voltage VDDA is lower than the second voltage VDDB, the pass time of the transistors N 10 , P 11 , and N 21 included in the first level shifting unit 110 is long. The pass time of the transistor N 40 included in the second level shifting unit 120 is long and the pass time of the transistors P 41 and N 43 is short.
Therefore, the total pass time of the first level shifting unit 110 is “L(N 10 )+L(P 11 )+L(N 21 )=3L”. The total pass time of the second level shifting unit 120 is “L(N 40 )+L(P 41 )+S(N 43 )=1L2S”. Thus, an average pass time of the first and second level shifting units 110 and 120 is “2L1S”.
Hereinafter, an operation where the first voltage VDDA is higher than the second voltage VDDB will now be described.
When the input signal IN transitions from a logic high level to a logic low level, since the first voltage VDDA is higher than the second voltage VDDB, the pass time of the transistors P 10 and N 20 included in the first level shifting unit 110 is short and the pass time of the transistor P 21 is long. The pass time of the transistors P 31 and N 41 included in the second level shifting unit 120 is short and the pass time of the transistor P 43 is long.
Therefore, the total pass time of the first level shifting unit 110 is “S(P 10 )+S(N 20 )+L(P 21 )=1L2S”. The total pass time of the second level shifting unit 120 is “S(P 31 )+S(N 41 )+L(P 43 )=1L2S”. Thus, the average pass time of the first and second level shifting units 110 and 120 is “1L2S”.
When the input signal IN transitions from a logic low level to a logic high level (first voltage VDDA level), since the first voltage VDDA is higher than the second voltage VDDB, the pass time of the transistors N 10 , P 11 , and N 21 included in the first level shifting unit 110 is short. The pass time of the transistor N 40 included in the second level shifting unit 120 is short and the pass time of the transistors P 41 and N 43 is long.
Therefore, the total pass time of the first level shifting unit 110 is “S(N 10 )+S(P 11 )+S(N 21 )=3S”. The total pass time of the second level shifting unit 120 is “S(N 40 )+L(P 41 )+L(N 43 )=2L1S”. Thus, an average pass time of the first and second level shifting units 110 and 120 is “1L2S”.
During a level change in the first and second voltages VDDA and VDDB, when the logic level of the input signal IN transitions, the average pass time of the first and second level shifting units 110 and 120 transitions between 2L1S and 1L2S. In more detail, the transition delay time of the average signal when the signal transitions from a logic high level to a logic low level, and the transition delay time of the average signal when the signal transitions from a logic low level to a logic high level changes by the same amount of time. Therefore, a duty rate of the output signals OUT of the first level shifting unit 110 and the second level shifting unit 120 remains unchanged.
FIG. 3 is a circuit diagram of the level shifting circuit shown in FIG. 1 according to an exemplary embodiment of the present invention. In comparison with FIGS. 2 and 3 , the level shifting circuit shown in FIG. 2 comprises a transistor NX 1 , whereas the level shifting circuit shown in FIG. 3 comprises a transistor PX 4 . Since the construction of the level shifting circuit shown in FIG. 3 corresponds to that of the level shifting circuit shown in FIG. 2 , the detailed description thereof will not be repeated.
FIG. 4 is a circuit diagram of a level shifting circuit according to an exemplary embodiment of the present invention. Referring to FIG. 4 , first and second level shifting units 110 and 120 correspond to the first and second level shifting units 110 and 120 , and thus the detailed description thereof will not be repeated.
A clamping unit 170 that comprises an NMOS transistor NX 0 differs from the clamping unit 170 shown in FIG. 2 . The transistor NX 0 may comprise a gate receiving a clamping signal CLAMP, a first end connected to ground, and a second end connected to output ends of the first and second level shifting units 110 and 120 .
When the clamping signal CLAMP has a logic high level, the transistor NX 0 is turned on, and the output ends of the first and second level shifting units 110 and 120 are fixed to a ground voltage irrespective of an average output signal of the first and second level shifting units 110 and 120 . Meanwhile, if the clamping signal CLAMP has a logic low level, the transistor NX 0 is turned off, and the average output signal of the first and second level shifting units 110 and 120 is output to the output ends of the first and second level shifting units 110 and 120 .
First and second operation control units 130 and 140 that comprise PMOS transistors PX 1 through PX 6 are distinguished from the first and second control units 130 and 140 shown in FIG. 2 . For example, the transistor PX 1 may comprise a gate receiving a clamping signal CLAMP, a first end connected to a signal transfer unit 118 , and a second end connected to a second voltage VDDB.
When the clamping signal CLAMP has a logic low level, the transistor PX 1 is turned on so that the signal transfer unit 118 is connected to the second voltage VDDB and performs a signal transit delay operation. However, when the clamping signal CLAMP has a logic high level, the transistor PX 1 is turned off and the signal transfer unit 118 is blocked from the second voltage VDDB and does not operate. Therefore, a logic level of the clamping signal CLAMP is adjusted in order to determine whether to operate the signal transfer unit 118 . If it is not necessary to operate the signal transfer unit 118 , a leakage current of the signal transfer unit 118 can be prevented.
The level shifting circuit shown in FIG. 2 may not comprise signal transfer units 118 and 126 and sub control units 134 and 144 . In this case, the first level shifting unit 110 may comprise a first inverter receiving an input signal and operating based on a first voltage, a first differential amplifier connected to an output end of the first inverter and operating based on a second voltage, and a second inverter in parallel to the first differential amplifier and connected to an output end of the first inverter and operating based on the first voltage. The first control unit may comprise a first sub control unit connected between the first differential amplifier and ground. The clamping unit may be connected between an output end of the first differential amplifier and the second voltage. The second level shifting unit may comprise a second differential amplifier receiving the input signal and operating based on the second voltage, a third inverter receiving the input signal, connected in parallel to the second differential amplifier, and operating based on the first voltage, and a fourth inverter connected to an output end of the second differential amplifier. The second operation control unit may comprise a second sub control unit connected between the second differential amplifier and ground and a third sub control unit connected between the third inverter and ground. The clamping unit may be connected between an output end of the fourth inverter and the second voltage.
The level shifting circuit according to exemplary embodiments of the present invention is capable of maintaining a duty rate irrespective of a voltage change, and is capable of fixing an output to a specific voltage level for a specific mode.
Further, parts of signal transfer units are blocked from an operation voltage or a ground for a specific mode, thereby preventing a leakage current.
Although exemplary embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the disclosure. | A level shifting circuit includes a first level shifting unit including a plurality of signal transfer units; a first operation control unit inactivating some of signal transfer units of the first level shifting unit in response to a clamping signal; a second level shifting unit connected in parallel to the first level shifting unit and comprising a plurality of signal transfer units; a second operation control unit inactivating some of signal transfer units of the second level shifting unit in response to the clamping signal; a signal output unit connected to output ends of the first and second level shifting units; and a clamping unit fixing the output ends of the first and second level shifting units to a predetermined voltage level in response to the clamping signal. | 7 |
BACKGROUND OF THE INVENTION
This invention relates generally to forming an eye at the end of a string or other rope-like item having a plurality of strands by dividing the strands into bundles or readies, twisting each bundle about its longitudinal axis, laying them over each other, and twisting them again back into the body of the string.
As used herein, the terms string, rope and bowstring each shall mean cordage of the indicated type comprising multiple discrete strands of which may be separated into multiple discrete strands extending generally parallel to one another longitudinally of the cordage.
While an eye may be woven into rope, string, or other cordage, it has found recent favor with archers for use in fabricating bowstrings. Most bowstring blanks are comprised of several strands wrapped near the middle of their length by a serving for placement of arrow notches when the bow is in use. In the past, bowstrings were of a specific predetermined non-variable length. The eyes or loops at each end of the bowstring were formed by splicing the ends of the strands back into the body of the string and wrapping the splice and loop circumferentially by a serving, thereby making it virtually impossible to change the string's length. This was done, in part, to provide a larger and stronger eye to fit over the wider limb nock at the end of a bow. Because the strength of or energy delivered by a bow is related to its degree of flexure, the string length is critical and a string with conventional loops and servings can be used to fit at only a single length.
By dividing the strands of one end of the string into bundles, twisting the bundles longitudinally, laying the ends over each other, and twisting the ends back into the body of the string, one may form an eye at the end of the string, sometimes referred to as a flemish eye. Although the flemish eye is known, its use has been severely limited and almost non-existant for archery due to the difficulty in properly making the eye and in accurately controlling the overall length of the finished string. As a result, archers have found it necessary to use the less desirable fixed length bowstring utilizing splices wrapped by a serving.
The presently disclosed apparatus and method of forming said eye provides a unique solution to the problems of manufacturing the more desirable bowstrings incorporating a flemish eye. Fabrication of a flemish eye, according to the teachings of the present invention, allows one to quickly, simply, and accurately position the eyes at the ends of a bowstring, thereby insuring a string of the desired length. Once fabricated, the eye will remain indefinitely until disassembled by the archer. This permits the added efficiency, convenience, and control of being able to readily use a bowstring blank at any length or quickly change its length to adjust string tension and bow flexure. This latter feature is of prime importance to those using modern day archery equipment, such as a two wheel compound bow.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide apparatus and an improved method for making an eye in a rope, string, or other cordage having a plurality of strands.
It is a further object of the invention to provide apparatus and an improved method for making an eye in a rope or string by dividing the strands of the string, twisting them longitudinally, laying them over each other, and twisting the ends back into the body of the string.
It is a further object of the invention to provide apparatus and an improved method for making ropes or strings of a specific, desired length with an eye on each end.
It is a specific object of the present invention to provide apparatus and an improved method for making eyes at the ends of bowstrings which may be readily removed if desired, in order to reuse a bowstring or adjust the length thereof.
It is still a further object of the present invention to provide apparatus and an improved method for making eyes at the ends of ropes or strings in a very short period of time.
These and other objects will become readily apparent from the present specification, drawings, and appended claims.
SUMMARY OF THE INVENTION
The invention includes apparatus for making an eye in a string, rope, or other cordage having a plurality of strands. The apparatus includes a first retaining means for releasably retaining strands of a string and longitudinally twisting at least two bundles of strands of said string, i.e. about their longiutdinal axis. A second retaining means is spaced apart from the first retaining means for gripping and retaining a portion of said string and may be placed in a plurality of positions spaced apart from said first retaining means. A rotating means is provided for rotating the first retaining means in either direction.
A method for making an eye in such a string includes splitting the strands of the string into first and second bundles and longitudinally turning each of these bundles in a first direction to provide a reverse twist in the main body section of the string. A distal end portion of the first bundle is then overlapped with a distal end portion of the second bundle to form a bight constituting the overlapped or double bundle portion. Said bight is releasably retained at its midpoint and the two segments or legs formed thereby are each twisted about its own longitudinal axis in a second direction opposite said first direction which also causes the legs of the bight to entwine one around the other forming an eye at said midpoint of the bight while unwinding the body section to a normal parallel untwisted state.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a flemish eye made in accordance with teachings of the present invention, said eye placed over a retaining end.
FIG. 2 is a perspective view of a splicing apparatus employing teachings of this invention.
FIG. 3 is a perspective view of one side of a rotatable strand retaining means.
FIG. 4 is a perspective view of a second side of a rotatable strand retaining means.
FIG. 5 is an exploded view of a preferred embodiment of a portion of a rotation means for a rotatable strand retaining means.
FIGS. 6A through 6D are perspective views showing a method for making an eye in a string employing teachings of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, a string 1 comprising a plurality of strands has an eye 2 that is placed over a retaining end 3, such as may be used for a compound bow. A first entwined portion 4 of said string 1 comprises end portions of the strands folded back on themselves to form a closed loop which provides the eye 2. The strands form two bundles 3a and 3b, each of which is twisted together, and the two twisted bundles are twisted or laid together as illustrated. The ends 6 of the strands are twisted in among the strands themselves for retention to form the loop of said first entwined portion 4. Because of the overlap, the portion 4 has an average diameter generally larger than the average diameter of a second portion 5 of the string 1. Said second portion 5 includes the strands of the string 1 entwined in two bundles 5a and 5b and laid together over a short length adjacent the first portion 4 to retain the ends 6 in place and prevent any undesired unraveling. At the opposite end of portion 5 the strands remain separated and parallel.
As seen in FIG. 2 of the drawings, an apparatus 8 for making an eye in a string or rope includes an elongated frame 10 having a first end 12 and a second end 14. The frame 10 is of generally channel-shaped or U-shaped cross-section in the preferred embodiment but may take a variety of convenient shapes. Mediate said first and second ends is a freely slidable string clamp 16. The clamp 16 includes a base portion 18 and an opposed pivoted clamping portion 20 which cooperates with the base portion 18 to releasably retain a string. A latch 19 holds the clamping portion 20 adjacent the base 18. In the case of a bowstring, said clamp 16 retains the center of the center serving of the string. Said clamp 16 is attached to a sliding means such as a block 22 which is slidably mounted on frame 10 in any convenient manner, e.g. in slots 19 in the interior cavity of the frame 10, so that the position of the clamp 16 may vary between the first end 12 and the second end 14 of the frame 10. Said string clamp 16 may swivel with respect to the sliding means 22 to permit either end of a string to be positioned toward a splicing head 30 attached to the frame 10 at the first end 12.
A string length stop 32 is slidably mounted on frame 10 in any convenient manner so that it may be releasably fixed in any position between the first end 12 and the second end 14 of the frame 10. In the illustrated embodiment, the stop 32 is a clamp including a plate (not shown) which slides in the slots 19 in a manner similar to that for mounting the sliding means 22 on the frame 10. A top plate 33 rides atop the frame 10, and an eyebolt 33a joins the plates to provide a clamping action for fixing the stop 32 in any selected stop position along the frame 10. The string clamp 16 normally abuts said stop 32. The relative position of said string clamp 16 or said stop 32 with respect to the splicing head 30 may be determined by reference to a string length scale 24 on the frame 10. Said scale 24 may be a ruler or any other length measuring indicia.
A tensioning means 26 also is slidably mounted on the frame 10 in any convenient manner to be releasably fixed in any selected position between the first end 12 and the second end 14 of the frame 10. Any conventional means suitable for use with the desired frame may be employed for the tensioning means 26. In the illustrated embodiment, means 26 is of the same slidable clamp construction and mounting as stop 32. An elastic tension element 34 engages a post 28 or other suitable connector on the tensioning means 26 and a post or other suitable connector (not shown) on the slide 22 to urge the string clamp 16 away from the splicing head 30 and toward the string length stop 32. The tensioner 34, which passes freely between the plates of stop 32, need only hold the string clamp 16 in an initial position against the string length stop 32 when the splicing operation commences. As splicing progresses, the twisting of the strands may vary the effective string length and draw the bowstring clamp 16 towards the splicing head 30. While tension in this portion of the string is not necessary, it is desirable in order to prevent tangling of the strands of said string.
A splicing head 30 is attached to the first end 12 of the frame 10. A righthand strand clamp 38 and a lefthand strand clamp 36 each is rotatably attached to the splicing head 30 by a shaft 72 or other means for rotation independent of said head 30. A rotary drive means 40 is connected to said strand clamps 36 and 38 in any conventional manner to rotate the clamps in either direction a desired number of turns. This may be done manually or automatically as desired. In the illustrated embodiment, the drive 40 includes means for converting reciprocating motion to rotary motion, such as that used in "automatic" screwdrivers or hand operated drills. A reciprocable control head 42, including a reversing switch 44, is concentric with and engages a shaft 46 having helical grooves 48 to translate the reciprocating motion of the control head 42 into rotary motion of said shaft 46. Trunnions and bearings (not shown) may be secured to the head 42 and engage the slots 19 to guide and control the movement of the reciprocating head. A coupling 50 connects said shaft 46 to a driving shaft 52, to rotate said strand clamps 36 and 38 by conventional means, such as gears 86 and 88 (see FIG. 5). A cable 54 and a foot pedal 56, together with a return spring (not shown), may be used to reciprocate said head 42 and thereby to rotate the shaft 46. The setting of the reversing switch 44 determines the direction of rotation of the shaft 46 and hence of the clamps 36 and 38.
Referring now to FIG. 5, the splicing head 30, in the preferred embodiment, comprises three rectangular laminated plates, namely a first plate 60, a second gear housing plate 62, and a third plate 64 which is substantially identical to said first plate in the preferred embodiment. The first plate 60 has two shaft apertures 68 and 70 to separately receive the two driven shafts 72, an aperture 73 to receive a driving gear shaft 52, and may include an aperture 76 to pass the cable 54 or other means to operate a manual rotating means 40. First plate 60 further includes an access slot 78 extending radially from aperture 68 to edge 80 and a slot 82 extending radially from aperture 70 to edge 80. Each of said slots 78 and 82 aligns with a radial slot 71 cut from the center of the respective shaft 72 to its periphery and extending the length thereof. The purpose of these slots is to admit strands of a string, as described further below.
Second gear housing plate 62 includes a trefoil-shaped opening 84 comprising three overlapping generally circular apertures whose centers are coincident with the centers for the three shaft apertures 68, 70 and 73 of the first plate 60. The radius of each generally circular aperture comprising opening 84 is greater than the respective radius of each gear housing within said second plate 62. Said gears include two driven gears 86, each of which has a radial slot 87 extending from its center to its circumference and each of which is attached to a slotted shaft 72 with the gear slots 87 in alignment with the shaft slots 71. A driving gear 88 is attached to said driving gear shaft 52. A port 90 in second plate 62 is as wide as and in line with the outer wall of slot 78 and the outer wall of slot 82 in first plate 60, and extends to and merges with opening 84. An aperture 92 in second plate 62 is coaxial with aperture 76 in first plate 60.
A third plate 64 may be substantially identical to the first plate 60. These three plates may be held together and attached to the frame 10 by any convenient means. As is clear from FIG. 5, the dimensions, number, and positioning of the apertures in the plates 60, 62 and 64 is dependent upon the means employed to rotate said strand clamps and may be varied or modified to accommodate the specific desires of one skilled in the art. Further, related items such as bearings, sleeves, guides, retainers, gears, couplings, etc., may be added or omitted as desired.
Referring now to FIGS. 3 and 4, right strand clamp 38 comprises a flat blade portion 94 attached, at its first end 95, substantially perpendicular to the surface of a disc 96 whose diameter is generally larger than that of the respective driven shaft 72. An access slot 97 extends radially from the approximate center of said disc 96 to its circumference. The disc 96 is attached concentrically to one end of the shaft 72, with slot 71 in said shaft in alignment with slot 97 of disc 96. The blade portion 94 includes a tooth 101 defining a slot 98 near the second end 100 of said blade 94 and opening to one side. A generally radial indentation 102 is mediate said first end 95 and said slot 98 and opens to the same side as said slot 98. A resilient yet relatively stiff arm 104 is attached to said disc 96 on the same surface as the blade 94, but on the side opposite the slot 97. Said arm 104 has a J-shaped distal end 106 which is oriented in the same direction as blade slot 98 and may extend thereinto. Left strand clamp 36 is a mirror image of right strand clamp 38, and like parts thereof are identified by the same part numbers in the drawings. The second strand clamp is attached in a similar manner to the second driven shaft. The strand clamps 36 and 38 may be modified or varied as desired by one skilled in the art to releasably retain the strands of a bowstring.
OPERATION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 6A, the apparatus 8 is shown loaded with a bowstring 110, comprising a plurality of strands wrapped circumferentially by a center serving 112. Such a bowstring typically is waxed, which may assist in the formation and retention of the eye as described herein. The string 110 is clamped, generally at its center depending upon the desired location of the center serving on the completed bowstring, and held in position by the string clamp 16. The string length stop 32 is fixed in position with reference to the string length scale 24. While the scale 24 is provided as an accurate reference, the actual position of the string length clamp 32 for a string of a desired length depends upon the specific desires of the archer and varies with, inter alia, the number and type of strands and the number of twists to complete the eye. Tensioning means 26 is fixed in any convenient position along the frame 10 to cause the tensioner 34 to urge the string clamp 16 away from the splicing head 30 and into abutting contact with the stop 32 to insure that the initial length of the bowstring 110 between the string clamp 16 and the strand clamps 36 and 38 is appropriate for the desired length bowstring.
The first end 114 of the bowstring 110 is placed toward the splicing head 30. The second end 116 (not shown in its full length, for clarity) may be placed anywhere convenient. The strands of said first end 114 are preferably substantially evenly divided into two bundles 118 and 120, or they may be divided otherwise to accommodate a particular archer's desires. One of said bundles of strands is threaded onto and engaged upon either one of the rotatable strand clamps 36 and 38. This is accomplished by passing each bundle through the slot 122 in the splicing head 30, said slot 122 resulting from the alignment of the slots 78 and 82 of the first and third plates 60 and 64 with the port 90 of the second plate 62. See also FIG. 6B. In alignment with the slots 122, and with one another as noted before, are the slots 97 in the discs 96 of the strands clamps, the slots 71 in the shafts 72, and the slots 87 in the driven gears 86. The alignment of these slots and the placement of said bundles in said slots near the center of rotation of said strand clamps allows each bundle to be longitudinally twisted along its length by the rotatable clamps. Each bundle is placed over the blade 94 of the strand clamp and threaded over the radial identation 102 to the opposite side of the blade having the arm 104 adjacent thereto. The bundle is further threaded over the tooth 101, through the slot 98, over the J-shaped distal end 106 of the arm 104, and extended longitudinally beyond the strand clamp a predetermined distance to define a bundle tail 124, see FIG. 6A. The exact geometry of threading the bundle through the strand clamp is not critical and many variations are possible to releasably retain the bundle thereat. The length of the bundle tail extending beyond the clamp is typically four to six inches and substantially determines the length of the first entwined portion 4 of the string 1 as shown in FIG. 1. The other bundle of strands is threaded onto the remaining strand clamp in a manner identical to the first bundle to define a second bundle tail 126. The bundles are preferably positioned in strand clamps 36 and 38 to remove any slack between said strand clamps and the string clamp 16.
Keeping the bundle tails 124 and 126 separate, the strand clamps 36 and 38 are both rotated in a first direction a predetermined number of times, such as 36 times clockwise, by driving the means 40 to put temporary longitudinal twists into each bundle 118 and 120. The free ends 119 and 121 of said bundles are allowed to rotate as the clamps 36 and 38 are rotated. As a result, the bundle tails 124 and 126 have no twists, and the twists induced are confined between the strand clamps 36 and 38 and the center serving 112.
Referring also to FIG. 6B, the bundle tail 124, with its first end 123 remaining in the strand clamp 36, is crossed over and its end 119 is threaded onto the other strand clamp 38. The end 121 of the other bundle tail 126 is similarly threaded onto strand clamp 36. The two bundle tails 124 and 126 now form an overlapped bight portion 128 between the two strand clamps. By a hook 130 or other similar device, the operator catches the center of the overlap portion 128 and draws it away from the splicing head 30 to a first position away from the strand clamps a distance approximately equal to one half the length of the original bundle tails 124 and 126, or until the ends 119 and 121 of the bundle tails 126 and 128 are about to be pulled free of the strand clamps 36 and 38, as seen in FIG. 6B. This action also draws the center serving 112 and the string clamp 16 toward the splicing head 30 and away from the string length clamp 32, but the tension device 34 keeps the bundles 118 and 120 relatively taut. With hook 130 remaining in said first position, the strand clamps 36 and 38 are rotated in a second opposite direction a given number of turns, such as 18 turns counterclockwise as indicated in FIG. 6C, to put longitudinal twists into each leg or half of the overlap portion 128. The two bundles also are permitted to entwine or lay about one another to form the first entwined portion 4 of FIG. 1. This laying will occur simultaneously with the twisting of the bundles if the holder 130 is permitted to rotate, or will occur subsequent to the twisting if the holder 130 is held in position during the twisting and subsequently released for induced rotation. As the strands entwine around one another due to the twisting, an eye 2 forms where said overlap portion 128 was caught on the hook 130. The hook 130 may rotate as described because of the torque exerted by the twisted strands or may be rotated manually. See FIG. 6C.
Referring now to FIG. 6D, the hook 130 is pulled to draw the eye 2 still further away from the splicing head 30 to a second position causing the bundle ends 119 and 121 to pull free from their respective strand clamps 38 and 36. With the hook 130 remaining in said second position, the strand clamps are further rotated in said second opposite direction a given number of turns, such as 10 turns counterclockwise as indicated in FIG. 6D, to further lock into place the two bundle tails 124 and 126 and to remove any residual temporary twists put into the bowstring during the preliminary twisting in the first direction. In an ideal situation, the number of twists in the first direction will equal the sum of the number of twists in the second direction so that the strands of bundles 118 and 120 are returned to unwound generally parallel relation. In practice, however, twists may pass through the strand clamp as the bundles are pulled through them. Accordingly, the sum of the number of twists in the second direction may be less than the number of twists in the first direction. The two bundles 118 and 120 are then freed from their strand clamps 36 and 38, as the formation of the eye is complete. The remnants of the bundle tails 124 and 126 may be left as illustrated in FIG. 6D to act as string silencers, as desired by hunters, or they may be trimmed flush with the circumference of the bowstring.
Forming an eye in the opposite end of the string is readily accomplished and is accurately positioned by rotating 180° the string clamp 16, placing said clamp 16 back into contact with the string length clamp 32, and then repeating the eye forming process. It is preferable to reverse the direction of rotation of the strand clamps 36 and 38 for each operation when forming the eye in the opposite end. This reverse formation counteracts the twists in the cables 7 (see FIG. 1) of a compound bow and keeps the bowstring 1 from twisting or rotating about its length as the bow is flexed. Any twisting causes the misalignment of bowstring mounted sights and exerts a torque on the arrow nock where it contacts the string. With the improved eye disclosed herein, the string is neutral and does not have a tendency to unwind, so the reverse twisting is not necessary, and the eye may be formed to suit the particular archer's desires.
The number of turns for each operation is variable and dependent upon the desired bowstring length. This may be coordinated with the string length scale 24 to develop an easy reference table for the making of strings of various lengths.
The invention has been described in detail with particular reference to a preferred embodiment and the operation thereof, but it is understood that variations, modifications, and the substitution of equivalent mechanisms can be effected within the spirit and scope of this invention, particularly in light of the foregoing teachings. | An apparatus and method for forming an eye at the end of a multiple-stranded rope, string or other cordage by dividing the strands into bundles, twisting them longitudinally, overlapping the end portions and reverse twisting them to form a flemish eye. The apparatus includes a frame and rotatable strand retaining clamps to retain and twist the strands of the string to form the desired eye, a string retaining means to help position the string, and rotating means to rotate the strand retaining clamps in either direction. | 3 |
The present invention relates to a method of and apparatus for transferring articles, particularly thin articles of a disclike nature, from one carrier member to another. The invention is particularly suitable for transferring unprocessed semi-conductor wafers from a first carrier member (hereinafter also referred to simply as a "carrier") to a second carrier member (hereinafter also referred to as a "magazine") so that they may be processed, e.g. in a furnace in which the magazine is introduced. The magazine therefore must be resistant to processing temperatures and in this particular art would generally be made from fused silica, whereas the carrier may be made from any suitable material, generally a suitable plastics material. The apparatus may also be used for re-transferring processed wafers back to the carrier. In the course of such transfer operations handling of the delicate wafers must be kept to a minimum to prevent damage and contamination which would lead to rejection of the very expensive articles.
BACKGROUND
Apparatus for effecting such transfer operations is already known e.g. from U.S. Pat. No. 3,949,891 filed July 22nd 1974 and entitled "Semi Conductor Wafer Transfer Device" but, irrespective of whether they are manually or automatically operated, they suffer from the disadvantage that the transfer was affected by bringing the two carrier members into an inverted position in register and the two devices were turned over, together. Therefore the wafers fell a distance roughly equal to the added depths of both carrier members; this may lead to cracking or chipping of wafer edges and lead to frequent rejection of the wafers.
THE INVENTION
It is therefore an object to provide a method of and transfer apparatus for this purpose which will respectively employ and operate with only a very small dropping movement of the articles and to reduce the risks of contamination by handling, to a negligible degree.
Briefly, the the invention consists in a method of transferring articles between first and second carrier members, includes a step wherein articles in a first carrier member are caused to pass nearly, but not quite wholly, into a second carrier member; then the carrier members are subjected to a displacement and said articles are allowed to pass wholly into said carrier member.
The carrier members are conveniently located in a housing and the displacement is effected by inverting said housing, advantageously by a rotary movement, the final movement of the articles being under the control of gravity.
The invention also provides transfer apparatus which comprises a displaceable housing for containing a baffle means adapted to receive articles from a first carrier member placed in the housing and pass such articles into a second carrier member along a distance less than that represented by a final desired position, the full distance to said final desired position being travelled by said articles only after displacement of said housing.
Advantageously the displacement referred to is an inversion, the housing, for this purpose, being rotatably mounted and the further distance travelled by the articles after rotational displacement of the housing being under the influence of gravity and of very small dimensions which is defined herein as being of the order of 2 mm.
Locking means are preferably provided to prevent the housing being inadvertantly displaced before the transfer of the articles.
For example, the housing may be mounted on a horizontal spindle for movement through 180° in either direction.
The housing may have frontal and/or lateral loading and unloading ports to enable the carrier members to be loaded into and unloaded from the housing.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be more clearly understood, reference will now be made to the accompanying drawings which show one specific embodiment thereof by way of example only, and in which:
FIG. 1 is a three-quarter view from the front of a first embodiment of a complete apparatus,
FIG. 2 is a three-quarter view from the front of a second embodiment of a complete apparatus,
FIG. 3 is a view of the shuttle baffle, to a larger scale, with a lateral portion separated,
FIG. 4 is a side view of the apparatus to a smaller scale and shown somewhat schematically to indicate the rotation axis of the housing.
FIG. 5 is a view of a carrier,
FIG. 6 is a view of a first type of magazine,
FIGS. 7 and 8 are views of second and third types of magazine, respectively, and
FIG. 9 is a view of a lifting fork.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, in FIG. 1 there is shown a first embodiment of a transfer mechanism incorporating the basic features of the invention and comprising a housing 1 rotatable about a horizontal axis in relation to a stand 2. The housing has a spindle projecting axially from its rear end to engage in anti-friction bearings in an aperture in the vertical portion 3 of the stand 2 (the spindle and aperture are not shown). The front end of the upper part of the housing is open, to gain access to a shuttle baffle 4, constituting the baffle means hereinabove referred to, and being in two parts 4a and 4b, the upper part 4b being slidable relative to the lower part 4a. The whole shuttle baffle unit is carried by and longitudinally slidable on, a pair of rails 5 secured to the inside of housing 1, the sides of the shuttle baffle being grooved at 6 for this purpose.
To the frontal end of the shuttle baffle 4a is secured a flange through a threaded aperture in which passes a threaded operating plunger 8, whose front end is secured to a hand wheel 9. Rotation of the hand wheel 9 effects a translational movement of the upper part 4b of the shuttle baffle, the rear end of plunger 8 bearing on the front end of part 4b. The translational movement of part 4b is stopped by a stop disc or plate secured to the rear face of part 4a (not shown). The rear end of plunger 8 may be coupled to the front end of part 4b in such a manner that the plunger 8 can rotate, or the part 4b may be spring-loaded so that in any event rotation of wheel 9 in one direction will affect a front to rear translation of the part 4b and a rotation of wheel 9 in the opposite direction will affect a rear to front translation of the part 4b.
In the lower part of housing 1 there is provided a platform 10 to which is secured a guide boss 11 through which passes a lifting pillar 12 to the upper end of which is secured a support member 13. A rack (not shown) is formed in or attached to the front longitudinal circumference of pillar 12, which rack is engaged by a pinion 14 secured to a shaft 15 which passes through the walls of the lower part of housing 1, as shown. To one end of shaft 15 is secured a handle 16, conveniently via a disc 17, outside the housing whereby rotation of handle 16 rotates shaft 15 to cause a vertical movement of pillar 12 and support member 13.
The spindle 15 also carries a cam disc 18 inside the casing and a locking rod 19 passes through the rear wall of housing 1 and is supported at its front end in a bracket 20 secured to the inner wall of the housing. The locking rod 19 passes rearwardly into an apertured boss 3a in the vertical part 3 of stand 2 so as to secure the housing 1 against rotation. The front end of rod 19 is spring-urged against the periphery of cam disc 18 so that when a cut-out 21 in cam disc 18 meets the front end of locking rod 19, the latter is urged forwardly to free the rear end of rod 19 from the apertured boss 3a in vertical part 3 to allow rotation of housing 1 about its horizontal mounting spindle. Similarly, the disc 17 carries a spring-loaded plunger, (not shown) passing therethrough into an aperture in the adjustment side wall of housing 1, the exterior end of this plunger bearing an operating head 22. It will be clear that at a suitable angular position of handle 16, this plunger will automatically enter the aperture and lock the shaft 15 against further rotation until the plunger is withdrawn by hand to release the shaft 15.
This construction enables transfer of articles from a first carrier member i.e. carrier 23, to a second carrier member i.e. a magazine 24 and vice versa the carrier 23 being a cage open at top and bottom and its side walls being grooved so as to receive a number of articles e.g. discs 26, such as semi-conductor wafers, the spacing between these side walls being such as to retain the articles 26 at diametrically opposite points so that they depend towards the open bottom of the cage.
The interior walls of parts 4a and 4b of shuttle baffle 4 are also grooved as 27 and 28 to allow passage of the articles 26 as will be explained. Preferably the grooved portions take the form of separate insert bodies screwed or otherwise secured to the respective baffle parts so that they may be removed for easy cleaning. Whilst any material found suitable may be used to make the shuttle baffle, we have found that polypropylene is one suitable material for the body thereof and the groove-inserts may be of polytetrafluoroethylene. The magazine 24 is made from fused silica and the stand and housing may be made from any rigid plastics material as are the other parts. The pinion and its associated rack may be made from nylon.
The magazine 24 is arranged to be clamped to the upper part of shuttle baffle 4 by means of locking arms 29, two on each side of the baffle 4, which are secured thereto by screws or the like so that they may pivot. The limbs of the arms 29 are pinned to operating rods 31 so that longitudinal movement of each rod causes the working arms 29 to pivot on their screws. If desired the one ends of each operating rod 31 may be secured together by transverse tie provided with an operating handle whereby movement of the latter may move both rods 31 and therewith all four arms 29 simultaneously, but this simple mechanical expedient will be apparent to those skilled in the art and has therefore not been shown. The magazine 24 is constituted by two longitudinal struts 32 and 33 joined together by transverse struts 34 and 35 and two further longitudinal struts 36 and 37 secured to the ends of the struts 34 and 35 which latter are in the form of tubes, open at their respective ends whereby the holder can be loaded unto and removed from the shuttle baffle 4 by a forked hand tool e.g. as shown in FIG. 9, comprising a handle device having two spaced tines arranged to be passed into the tube ends.
The interior surface of the struts 32, 33, 36 and 37 are transversely grooved, each set of four grooves being intended to accommodate one article such as a disc 26, but the spacing between the grooves in these struts as well as the grooves 28 in part 4b of the shuttle 4, is half that of the grooves 25 in carrier 23 and grooves 27 in part 4a of baffle 4, so that the magazine 24 is capable of holding twice as many articles as the carrier 23. However, it will be appreciated that this pertains only to the embodiment shown and the holding capabilities of the carrier members may be varied as desired.
An empty magazine 24 is placed upside down, as shown, on the upper face of baffle part 4b and is locked in position by locking arms 29 whilst the baffle 4 is outside the apparatus. The baffle is then slid into the upper part of housing 1 on slide rails 5. A carrier 23, loaded with articles 26 is inserted into housing 1 beneath the baffle 4. The operating head 22 is then pulled out under spring pressure, to release its plunger from the aperture in the wall of the lower part of housing 1. The handle 16 can then be operated to lift pillar 12 and support member 13 to cause the articles 26 to pass into the baffle 4 occupying alternate grooves in part 4b, until the plunger on head 22 again locks handle 16 at which time it is arranged that the articles 26 do not fully bottom in the grooves in longitudinal struts 32, 33 i.e. they are not fully "home" into the magazine 24, being short by, say, 2 mm. At this time the locking rod 19 will also be freed from part 3 of stand 2 whereupon the housing 1 is rotated clockwise through 180° until it reaches a stop (not shown), thus inverting the carrier members so that they exchange positions. The shuttle baffle 4 is then indexed by rotating hand wheel 9 until it meets and end stop thereby achieving the closure of grooves occupied by the first load of articles 26, and opening each unoccupied slot in magazine 24 and part 4b of baffle 4, ready to receive the second load of articles 26. The articles 26 thus enter the magazine 24 with minimum force by gravity but they will have suffered no damage due to the fact that the dropping distance is so small.
The housing 1 is then rotated anti-clockwise through 180° and returned to its initial position. The operating head 22 is then retracted and handle 16 is moved back to its start position, thereby returning support member 13. The empty carrier 23 is removed and replaced by a second loaded one and the operation is repeated, the articles from this second carrier being loaded into the grooves between those first loaded. Thus the magazine 24 contains the contents of both carriers 23, the second "load" also having been gently dropped into the "home" position on the next rotation of the housing 1.
The shuttle baffle 4 can then be removed from the apparatus and magazine 24 lifted off after releasing the locking arms 29.
Unloading a magazine 24 and distributing its load of articles 26 into two carriers 23, is carried out by a reversal of the above procedure.
Referring now to FIGS. 2 to 9 of the accompanying drawings, the transfer mechanism therein shown is more sophisticated than that shown in FIG. 1 and comprises a housing 40 rotatable about a horizontal axis (see FIG. 4) in the vertical wall 42 of a stand 43. This horizontal axis takes the form of a shaft projecting axially from the rear end 44 of the housing, passing through a boss 45, to engage in antifriction bearings 46 in an aperture in the vertical wall 42 of the stand 43 (FIG. 4). The frontal end of the upper part of the housing 40 is open at 47, to gain access to a shuttle baffle 48 that is in two vertically-separated parts 48a and 48b, the upper part 48b being slidable relative to the lower part 48a. The whole shuttle baffle unit is carried by and longitudinally slidable on, a pair of rails 49 secured to the inside of housing 40, the sides of the shuttle baffle being grooved at 50 for this purpose. The housing also has a lateral loading and unloading port 51.
To the frontal end of the shuttle baffle 48a is secured a flange 52 through a threaded aperture in which passes a threaded operating shaft, whose front end is secured to a hand lever 53, movement of which effects a translational indexing movement of the upper part 48b of the shuttle baffle with respect to the lower part 48a but the two parts cannot be vertically separated due to a dovetail-grooved connector 48c between them, the rear end of the shaft secured to lever 53 bearing on the front end of part 48b. The translational movement of part 48b is stopped by a stop disc or plate secured to the rear face of part 48a (not shown). The rear end of said shaft may be coupled to the front end of part 48b in such a manner that the shaft can rotate, or the part 48b may be spring-loaded so that in any event rotation of lever 53 in one direction will affect a front to rear translation of the part 48b and a movement of lever 53 in the opposite direction will affect a rear to front translation of the part 48b.
In the lower part of housing 40 there is provided a platform 54 to which is secured a guide boss 55 through which passes a lifting pillar 56 to the upper end of which are secured lifting bars 57. A rack (not shown) is formed in or attached to the front longitudinal circumference of pillar 56, which rack is engaged by a pinion 58 secured to a shaft 59 which passes through the walls of the lower part of housing 40 as shown. To one end of shaft 59 is secured a handle 60, conveniently via a disc 61, outside the housing whereby rotation of handle 60 rotates shaft 59 to cause a vertical movement of pillar 56 and lifting bars 57.
The spindle 59 also carries a cam disc 62 inside the casing and a locking rod 63 passes through the rear wall of housing 40 and is supported at its front end in a bracket 64 secured to the inner wall of the housing. The locking rod 63 passes rearwardly into an apertured boss 65 in vertical wall 42 of stand 43 so as to secure the housing 40 against rotation. The front end of rod 63 is spring-urged against the periphery of cam disc 62 so that when a cut-out 66 in cam disc 62 meets the front end of locking rod 63, the latter is urged forwardly to free the rear end of rod 63 from the apertured boss 65 in vertical wall 42 to allow rotation of housing 40 about its horizontal mounting spindle 41. Similarly, the disc 61 carries a spring-loaded plunger, (not shown) passing therethrough into an aperture in the adjacent side wall of housing 40 the exterior end of this plunger bearing a locking knob 67. It will be clear that at a suitable angular position of handle 60, this plunger will automatically enter the aperture and lock the shaft 59 against further rotation until the plunger is withdrawn by hand to release the shaft 59.
This construction enables transfer of articles from a carrier 68 to a magazine 69 and vice versa, the carrier 68, being a cage open at top and bottom (see particularly FIG. 5), and its side walls being grooved at 70 so as to receive a number of articles e.g. discs 71, the spacing between these side walls being such as to retain the articles 71 at diametrically opposite points so that they depend towards the open bottom of the cage.
The interior walls of parts 48a and 48b of shuttle baffle 48 are also grooved at 72 and 73 to allow passage of the articles 71 as will be explained. The spacing between the grooves 73 is half that between the grooves 72 so that selected ones of the grooves 73 can be used when transferring articles 71 from a carrier 68 to a magazine 69 and vice versa by effecting appropriate indexing horizontal travel of the upper part 48b of the baffle 48 by operation of lever 53 as will be referred to later.
Preferably the grooved portions take the form of separate insert bodies 74, 75 screwed or otherwise secured to the respective baffle parts so that they may be removed for easy cleaning. Whilst any material found suitable may be used to make the baffle, it has been found that polypropylene is a very suitable material for the body of the shuttle and the groove-inserts may be of any suitable temperature-stable material such as PFTE (polytetrafluoroethylene) or PFA (perfluoro-alkane). The magazine 69 is made from fused silica and the stand 43 and housing 40 may be made from any suitable rigid plastics material as are the other parts. The pinion 58 and its associated rack may be made from nylon.
In using the apparatus, a magazine 69 may be located on the top face of the shuttle 48 between opposed pairs of pegs 76 or 77 at each end of the baffle. These pegs are mounted on sliders 78, one at each corner of the upper face of the baffle. As will be apparent from the drawings, particularly FIG. 3, the respective pegs 76 and 77 are longitudinally staggered so that the width across the baffle top between each pair 76 and 77 is different. Thus magazines of two different widths can be located as desired by removing each slider 78, turning it through 180° and replacing it so as to use alternative pegs.
The upper part 48b of the baffle has a removable rectangular side portion 48d which is located on the main portion by pegs 79 projecting from the lateral inner faces of the other portion and into holes 80 as shown. Alternatively the pegs may be on one portion only and the apertures in the other if desired. The two portions are locked together under the control of a locking knob 81 mounted for example at the end of a spindle having a detent engaging in a cut-out or aperture in the under-part of the upper peg 79. Any desired locking arrangement may be used, and since it may take any of the forms well known by those experienced in mechanical techniques it need not be, and therefore has not been, further described or illustrated here. A handle member 82 is provided to enable the portion 48d to be easily manipulated. A support platform 83 is located above and spaced from the baffle 48 on posts 84 to prevent the magazine 69 from falling out by gravity when the housing is rotated through 180° with respect to the position shown in FIG. 2 for the purpose which will be referred to later.
The removable block portion 48d of the upper part 48b of baffle 48 can be removed laterally from the housing through the aperture 51 in the side wall thereof.
The magazine 69 (FIG. 6) is constituted by two longitudinal struts 85 and 86 joined together by transverse struts 87 and 88 and two further longitudinal struts 89 and 90 secured to the ends of the struts 87 and 88. The struts 85 and 86 may be provided with apertures whereby the magazine can be loaded into and removed from the shuttle baffle 48 by a forked hand tool 91 (FIG. 9) comprising a handle device having two spaced tines 92, 93 arranged to be passed into the apertures or simply beneath the struts 80 and 90.
The interior surfaces of the struts 85, 86, 89 and 90 are transversely grooved at 94, each set of four grooves being intended to accommodate one article such as a disc 71, but the spacing between the grooves in these struts as well as the grooves 73 in part 48b of the shuttle 48, is half that of the grooves 70 in carrier 68 and grooves 72 in part 48a of the baffle 48, so that the magazine 69 is capable of holding twice as many articles as the carrier 68. However, it will be appreciated that this pertains only to the embodiment shown and the holding capabilities of the members may be varied as desired. The struts 89 and 90 are notched at 95 to receive the pegs 76 or 77 on the baffle.
The operating procedure for using the transfer apparatus hereinabove described will now be set forth.
To load a magazine 69 in two stages, from two loaded carriers 68, the locking knob 67 is pulled outwardly to enable the handle 60 to be rotated clockwise thus raising the lifting bars 57, until the handle 60 locks the shaft 59 against further rotation. The housing 40 is then rotated clockwise through 180° until it reaches its stop position. The machine is now in the mode opposite that shown in FIG. 2 with the support platform 83 lowermost.
At this juncture the locking knob 81 in baffle part 48b is withdrawn to release baffle part 48c which can then be removed by handle 82 through the side opening 51 of the housing 40.
To avoid touching the magazine by hand which would transfer undesired grease thereto, a magazine 69 is lifted by lifting fork 91 and placed on the platform 83, the pegs 76 and 77 on the baffle engaging in the notches 95 of the magazine. Then the locking knob 81 is pulled out and the removable portion 48c of the baffle is replaced, whereupon the housing 40 can be returned to its initial position by rotating it anti-clockwise through 180°.
Next, assuming that the upper portion 48b of the baffle is towards the front of the apparatus, the lever 53 is turned from right to left until the movement of this upper portion away from the operator ceases when its rear end reaches its stop.
At this stage the locking knob 67 is pulled out to release the associated peg from the side wall of the housing and the handle 60 is rotated clockwise to rotate shaft 59 and lower the lifting bars 57 to the start position.
A first carrier member loaded with articles such as silicon wafers 71 is then placed on the floor 96 of the housing 40 whereupon the locking knob 67 is again pulled out to re-rotate the handle 60 clockwise to raise the lifting bars 57 until the handle 60 locks in position again. This transfers the articles 71 from the carrier 68 into the lower portion 48a of the baffle and up into alternate grooves in parts 48b and 48d and hence into the magazine 69, but the travel of the lifting bars 57 is arranged so that the articles 71 are not fully "home" in the magazine 69, being short by say, 2 mm, i.e. they do not bottom in the grooves 94.
The housing 40 is then rotated clockwise by 180° until it reaches the stop. The lever 53 is then moved from left to right to translate the upper portion 48b and 48d of the baffle towards the operator. The housing 40 is then rotated anti-clockwise by 180° until it reaches the stop when the locking knob 67 can again be released to lower the lifting bars 57 by operating handle 60 anti-clockwise until the bars 57 are at the start position again.
The first carrier 68, which is now empty, can now be removed and replaced by a second one loaded with articles 71 and the operations described above can be recommenced except that translation of the upper part 48b and 48d of the baffle will close off those grooves in the magazine 69 and render the second alternate set of grooves therein accessible to receive the articles from the second carrier 68, still however not fully "home" in the magazine.
Now, with the fully loaded magazine in the upper part 48b and 48d of the baffle, the housing 40 can again be rotated clockwise through 180° away from its stop until it reaches again the position opposite that shown in FIG. 2 i.e. with the platform 83 of the shuttle baffle 48 lowermost. As the housing reaches this position, the articles will drop the last little distance completely "home" into the magazine but, due to the small travel of about 2 mm, they will not suffer any damage which is a fault experienced in transfer devices of the prior art even those employing an arrangement to perform a similar kind of indexing movement as described above to effect a transfer between two frame sections having single and double groove spacing and indexing movements between the sections analogous to that of the present invention.
With the articles 71 safely "home" in the magazine 69, the locking knob 81 can then be pulled out to remove the removable block portion 48d of the shuttle baffle 48 by handle 82, together with the fully loaded magazine 69, which can then be taken off the platform 83 by the lifting fork 91.
To carry out the reverse operation to unload a fully loaded magazine into two carriers 69 in two stages, the procedure described above is virtually repeated and can be summarised as follows.
The apparatus is, for this purpose of course in the reverse position to that shown in FIG. 2. The fully loaded magazine is placed on the platform 83, the locking knob 81 is pulled out and the removed block 48d is replaced and the housing 40 with the loaded magazine is rotated by 180° until it meets the stop. The locking knob 67 is then pulled out and the lifting bars 57 lowered by operating handle 60 so that the carrier 68, previously placed on base 96, and now filled with articles 71 can be removed by hand and replaced by an empty second carrier 68. Then locking knob 67 is pulled out, lifting bars 57 are raised by turning handle 60 and housing 40 is rotated clockwise by 180°. At this juncture the lever 53 is moved from left to right until the movement of the parts 48b and 48d of the baffle away from the operator ceases whereupon the housing 40 is again rotated anti-clockwise by 180° until it reaches the stop so that locking knob 67 can again be operated to lower bars 57 until handle 60 locks to allow the second loaded carrier 68 to be removed.
At this stage, the magazine 69 is still in the apparatus so the knob 67 must be operated to turn handle 60 to raise bars 57 until handle 60 locks. Then housing 40 is rotated clockwise by 180° until it stops, locking knob 80 is pulled out, block 48d is removed, together with the empty magazine and the latter is removed by lifting fork 91.
The empty apparatus can now be restored to the position shown in FIG. 2 ready for another loading/unloading sequence.
Whilst only one kind of magazine 69 has been shown it will be clear that other kinds may be used. In particular the magazine may be varied to accommodate doping discs where the apparatus is used for transferring silicon wafers, by enlarging every third slot in the magazine to take a solid source disc i.e. one containing a dopant such as boron and the mechanism may be modified to enable the magazine to be loaded with "ordinary" wafers after such solid source discs are in situ.
It will also be apparent that while the apparatus has been described to perform a transfer of articles from a carrier to a magazine, it could be arranged to transfer articles between carriers or between, say a carrier and a transport case for taking away or storing finished silicon wafers after processing.
The magazine 69 may be made from low-mass silica which will withstand a furnace temperature of up to 1050° C. If it is desired to process wafers or other articles 71 in temperatures up to 1200° C. then a magazine such as shown at 87 in FIG. 7 made from silicon, or another such as 98 in FIG. 8 made from silica glass, may be used, both exhibiting the notches 95 to receive the baffle pegs 76 or 77. | Articles, such as fragile, delicate semiconductor wafers, in a first carrier member are caused to pass nearly, but not quite wholly, into a second carrier member by being pushed--against gravity--thereinto. The carrier members are then subjected to a displacement, e.g. by inversion, and said articles are allowed to drop wholly into said second carrier member. The further distance travelled by the articles after rotational displacement of a housing retaining the carrier members is very small, e.g. about 2 mm. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of Ser. No. 318,753 filed Mar. 3, 1989 issued as U.S. Pat. No. 5,009,892.
TECHNICAL FIELD
This invention relates to a miotic agent useful in post-operative cataract and intraocular lens surgery and, more particularly, to a combination of miotic agents that provides quick miosis with control of intraocular pressure 24 hours after surgery.
BACKGROUND OF THE INVENTION
Miotic agents are frequently used by ophthalmologic surgeons during intraocular surgery. The anterior chamber is irrigated with a miotic agent after delivery of the lens in cataract surgery as well as in penetrating keratoplasty, iridectomy and other anterior segment surgery. Prompt miosis is necessary to ensure that a round pupil is obtained after cataract surgery. If any of the iris of the eye is caught in the incision or if a capsular tag is caught in the incision, the pupil will be distorted on the following day. It is easy to miss a capsular tag in the incision since the tag is clear and transparent unless one uses a miotic agent. The other advantages obtained by the use of miotics are the facilitation of post-placed corneal scleral sutures, anterior chamber lens insertion and a decrease in post-operative peripheral anterior synechias. Many surgeons feel that miotic agents help in centering and positioning the intraocular lens implant.
Elevated intraocular pressure (IOP) can interfere with normal functioning and may result in irreversible loss of visual function. Viscoelastic agents such as Healon are often used during lens implantation which can cause elevated IOP with pressure spiking.
With the advent of modern surgical techniques and the trend to "in the bag" placement of posterior chamber intraocular lens' (IOL), more and more viscoelastic substances are being used. Increasingly, cataract surgery is being done on an out-patient basis, and the patient returns to the physician's office the following day. Slit lamps and applanation tonometry are handy, and consequently most surgeons are examining their post-operative patients even better than when they were hospitalized. This has improved patient care and, on the other hand, has perhaps resulted in increased awareness of the IOP 20-24 hours after cataract surgery.
Pressure studies have shown that the IOP in the first 24 hours after cataract surgery may be very important. Damage by raising IOP is possible to the optic nerve, the vascular supply within the eye, and the corneal endothelium (15)(7). Consequently, every effort should be made to control the IOP from the very onset of the post-operative period.
Acetylcholine (Miochol) is the most popular miotic agent utilized by ophthalmologic surgeons. Miochol provides quick miosis (within minutes). However, it provides very poor control of IOP after several hours, even when pressure control agents such as acetazolamide (Diamox) are utilized. Carbachol (Miostat) does not provide as quick a miosis and is not as widely used. A miotic agent providing quick miosis with control of intraocular pressure 24 hours after surgery is needed.
DESCRIPTION OF THE PRIOR ART
Gormaz (3), in 1962, first reported increases in IOP in the immediate period after cataract extractions. Rich (4) (5) in 1968 and 1969 found a significant rise in IOP was characteristic after cataract surgery. He also showed that α-chymotrypsin was not required to produce this increase. Sodium hyaluronate (Healon) has been implicated as causing a rise in IOP. Olivius and Thornburn (6) have shown that sodium hyaluronate induced increased IOP, and is partially reversible by removal or dilution of the viscoelastic material by irrigation (7).
Several drugs have been used to counteract the increase in IOP associated with cataract surgery. Rich (3) in 1969 demonstrated a lowering of IOP 24 hours after surgery with the use of acetazolamide (Diamox) in high doses during the 24 hours following cataract surgery. However, acetazolamide has some undesirable side effects in some patients. Although Timolol effectively lowered IOP after ICCE (intracapsular cataract extraction) (8), it was found to have no effect in acute post-operative pressure evaluations following ECCE with IOL and the use of sodium hyaluronate (9). Recently, a simple administration of pilocarpine gel was found to be effective in reducing IOP for the first 24 hours after ECCE with IOL (10). However, patients frequently complained of brow ache the next day. This same group, however, felt that there was a trend in lowering IOP post-operatively using Timolol.
Miotic agents came into use in about 1970, shortly after the onset of ECCE. In 1972, Beasley (11) found that miosis was rapid with both acetylcholine 1% and carbachol 0.01%. With carbachol, miosis extended into the first post-operative day, unlike acetylcholine, where the miotic effect is gone within a very short time. However, Hollands, Drance and Schulzer (13), showed that acetylcholine 1% has a more rapid onset of miosis than does carbachol 0.01%. Hollands, Drance and Schulzer (14) showed that acetylcholine 1%, administered intracamerally during cataract surgery, significantly reduced the IOP at 3 and 6 hours post-operatively but had no effect beyond this time. On the other hand, this same group of investigators showed that carbachol 0.01% was highly effective in reducing IOP for at least 24 hours post-operatively, and in reducing the number of patients developing IOP greater than 30 mm Hg.
List of Cited References
1. U.S. Pat. No. 4,459,309.
2. U.S. Pat. No. 4,665,094.
3. Gormaz, A., Ocular Tension After Cataract Surgery, American Journal of Ophthalmology, 43:832, 1962.
4. Rich, W. J. C. C., Intraocular Pressures and Wound Closure After Cataract Extraction. Trans. Ophthalmol. Soc., U. K. 88:437, 1968.
5. Rich, W. J. C. C., Further Studies on Early post-operative Ocular Hypertension Following Cataract Extraction. Trans. Ophthalmol. Soc., U. K. 89:639, 1969.
6. Olivius, E. and Thornburn, W., Intraocular Pressure After Surgery with Healon. Am. Intraocular Implant Soc. J. 11:480, 1985.
7. Cherfan, G. M., Rich, W. J. and Wright, G., Raised Intraocular Pressure and Other Problems with Sodium Hyaluronate and Cataract Surgery. Trans. Ophthalmol. Soc., U. K. 103:277, 1983.
8. Obstbaum, S. A. and Galin, M. A., The Effects of Timolol on Cataract Extraction and Intraocular Pressure. Am. J. Ophthalmol. 88:1017, 1979.
9. Tomoda, T., Tuberville, A. W. and Ward, T. O., Timolol and Postoperative Intraocular Pressure. Am. Intraocul. Implant Soc. J., 10:180, 1984.
10. Ruiz, R. S ., Wilson, C. A., Musgrove, K. H. and Prager, T. C., Management of Increased Intraocular Pressure After Cataract Extraction. Am. J. Ophthalmol., 103:487, 1987.
11. Beasely, H., Miotics in Cataract Surgery, Arch. Ophthalmol., 88:49, 1972.
12. Douglas, G. R., A Comparison of Acetylcholine and Carbachol Following Cataract Extraction. Can. J. Ophthalmol., 8:75, 1973.
13. Hollands, R. H., Drance, S. M. and Schulzer, M., The Effect of Intracamerol Carbachol on Intraocular Pressure After Cataract Extraction. Am. J. Ophthalmol., 104:225, 1987.
14. Hollands, R. H., Drance, S. M. and Schulzer, M., The Effect of Acetylcholine on Early Postoperative Intraocular Pressure, Am. J. Ophthalmol., 103:749, 1987.
15. Hayrch, S. S., Anterior Ischemic Optic Neuropathy, IV, Occurrence After Cataract Extraction, Arch. Ophthalmol., 98:1410, 1980.
STATEMENT OF THE INVENTION
An improved miotic agent is provided in accordance with this invention that provides rapid miosis with 24 hours control of intraocular pressure. The miotic agent of the invention reduces or eliminates the need for IOP control agents such as Diamox and reduces IOP after use of viscoelastic agents such as Healon.
The miotic agent of the invention resides in the combined use of an acetylcholine type of agent with a carbachol type of agent. The combination provides fast onset of miosis, a prolonged miotic effect, and long-term control of IOP for 24 hours. The IOP is maintained at or below 25 mm Hg with very few, if any, pressure spikes in the 24 hour, post-operative period.
The miotic agent of the invention is convenient to use. The agent is safe and effective since it is a combination of two agents approved for use in the same procedure. The miotic agent of the invention will find general use in intraocular surgery and is especially useful in the class of patients who enter the procedure with elevated intraocular pressure, such as glaucoma patients. It will also prove very useful in procedures in which Healon is used to aid in the insertion of an intraocular lens.
The acetylcholine and carbachol materials can be used sequentially or simultaneously. Another aspect of the invention resides in packaging the two agents in a common container having two separate compartments. The agents are combined and dissolved in a common carrier immediately before use.
These and many other features and attendant advantages of the invention will become apparent as the invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1a is an enlarged view of a package containing the component of the miotic agent of the invention;
FIG. 1b is a view taken along line 1b--1b of FIG. 1a;
FIG. 1c is a view similar to FIG. 1b but showing unit dosage and aqueous solution mixed and ready to be withdrawn by a hypodermic needle;
FIG. 2 is a set of curves showing pre-operative and post-operative intraocular pressure IOP in a group of patients receiving Miochol with Diamox;
FIG. 3 is a set of curves showing pre-operative and post-operative intraocular pressure IOP in a group of patients receiving Miochol without Diamox;
FIG. 4 is a set of curves showing pre-operative and post-operative intraocular pressure IOP in a group of patients receiving Miostat with Diamox;
FIG. 5 is a set of curves showing pre-operative and post-operative intraocular pressure IOP in a group of patients receiving Miostat without Diamox;
FIG. 6 is a set of curves showing pre-operative and post-operative intraocular pressure IOP in a group of glaucoma patients receiving Miochol;
FIG. 7 is a set of curves showing pre-operative and post-operative intraocular pressure IOP in a group of glaucoma patients receiving Miostat; and
FIG. 8 is a series of bar graphs illustrating the pre- and post-operative IOP in 18 patients administered the combined miotic agent of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The first active agent in the miotic composition of the ##STR1## where R and R 1 and lower alkyl groups containing 1 to 5 carbon atoms and X - is an anion such as halo.
The preferred member of this group is acetylcholine where R and R 1 are all methyl and X - is chloro. Acetylcholine is a parasympathemetic agent. It is utilized in concentrations from 0.1 to 5% usually at 1% by weight. Acetylcholine is unstable so it is provided in dry powder form and is mixed with physiologically inert, liquid carrier before use. The dry material can be mixed with an inert lyophilizing material such as mannitol in ratios of 1/1 to 10/1, usually 3/1 by weight. The reconstituted aqueous solution contains 1% acetylcholine and 3% mannitol by weight. The usual doses for administration is about 2 ml.
The second active material in the miotic composition is a compound of the formula: ##STR2## where R 2 is a low alkyl group of 1-5 carbon atoms, n is an integer from 0-3 and X is an anion such as halo. The preferred material carbachol, is a compound in which n is O, R 2 are all methyl and X is chloro. Carbachol is provided as a sterile aqueous salt solution in a concentration from 0.001 to 1.0 percent by weight, usually at about 0.01% by weight. The isotonic salt carrier includes the following inactive salts:
______________________________________Salt % by Weight______________________________________NaCl 0.64KCl 0.075CaCl.sub.2.H.sub.2 O 0.048MgCl.sub.2.6H.sub.2 O 0.03Sodium acetate.3H.sub.2 O 0.39Sodium citrate.2H.sub.2 O 0.17______________________________________
The pH is adjusted to neutral with sodium hydroxide or hydrochloric acid as needed.
Referring now to FIG. 1, the two agents can be provided in a two compartment package 10. The package is in the form of a uni-vial 12 having a first compartment 17 sealed by a first elastomer plug 18 and a second compartment 14 sealed by a second elastomer plunger-stopper 16. The first compartment 17 contains a unit dosage or charge 22 of the first agent such as acetylcholine and the lyophilizing agent such as mannitol and the second compartment 14 contains an aqueous solution 20 of the second agent in a solution of salt in isotonic proportions and concentrations. The plunger-stopper 16 is pressed downwardly which forces the plug 18 into the lower compartment. The plunger-stopper 16 comes to rest on the shoulder 25 formed along the rim 27 of the annular section 31 of the uni-vial 12. The solution 20 falls into the first compartment 17 and dissolves the dry charge 22. In use, a hypodermic needle, not shown, is inserted through the plunger-stopper 16 into a second compartment 14 to withdraw the solution. After the dry mixture of compounds is dissolved, the combined miotic agent is withdrawn into the syringe and is ready for use.
Studies were conducted using Miochol (acetylcholine) and Miostat sequentially, and combined separately during intraocular surgical procedures.
The miotic agent of the invention can be used as follows. After extraction of a cataract, the capsule is retained. It has an anterior flap. To facilitate insertion of the lens, the capsule is inflated and Healon is applied. After insertion of the lens in the capsule, the Miochol agent is injected. As the pupil is constricting, closure of the wound takes place. The viscoelastic agent is removed from the capsule coating by aspiration with saline. The Miostat solution is then added to the anterior chamber. As the last stitching of the incision is completed, the iris is examined for roundness and for inclusion of iris or capsular tags in the incision.
When the combination of acetylcholine and carbachol is utilized in a common carrier, a portion of the combination solution is added after lens insertion and closure of the wound takes place. The viscoelastic agent is aspirated from the anterior chamber and the combination miotic agent is added again as the stitching of the wound is completed.
The following studies provide indications of the ability of the combination miotic agent of the invention to provide long-term IOP control without the use of Diamox and excellent control of glaucoma patients undergoing ECCE.
The average intraocular dose of Miochol is 0.5 to 2 ml of the 1% solution and of the carbachol during surgery is 0.5 to 2 ml of a 0.01% solution.
The intraocular pressure was measured with the Goldman applanation tonometer the day before surgery during the pre-operative visit. The second intraocular pressure measurement was taken 20-24 hours after surgery at the first post-operative visit.
SURGICAL TECHNIQUE
1. Standard ECCE with intraocular lens implantation (either PMMA (Polymethylmethacrylate) with Prolene loops, or all PMMA) was performed. All phakoemulsification with intraocular lens implantation patients were excluded. All known glaucoma patients were also excluded from this part of the study.
2. Methods and procedures: (a) Honan cuff 15-30 minutes pre-operatively, (b) approximately 11 mm incision, (c) manual extracapsular cataract extraction (pressure below, counter-pressure above), (d) Healon (sodium hyaluronate) was used in all cases, (e) machine cortical irrigation and aspiration containing epinephrine with either Site unit or Series 10,000 Coopervision unit, (f) "in the bag" placement of the posterior chamber intraocular lens, (g) machine irrigation and aspiration of Healon, (h) Miotic agent instilled into the anterior chamber and the chamber was aspirated to remove the Healon, (i) closure with interrupted 10-0 nylon sutures.
Injectable medication used at surgery were Garamycin (1/2 to 1 cc), and Celestone (1/4 to 1 cc).
3. Topical medications used upon completion of surgery were Tobrex, Maxidex, and Betoptic, Celestone, Maxidex and Betoptic are underlined because they are known to affect intraocular pressure.
ECCE surgery has been conducted utilizing acetylcholine and carbachol sequentially and combined on two sets of patients. All surgeries were successful with quick miosis followed by rapid lowering of IOP and low IOP after 24 hours.
The following table and FIG. 8 show the IOP of 9 patients administered the two miotic agents sequentially. Quick miosis was observed. The Post-Op IOP (24 hours after surgery) was the same or lower than the Pre-Op pressure.
TABLE 1______________________________________Patient Pre-Op Post-Op Delta IOP______________________________________1 15 15 02 15 16 13 12 7 -54 19 20 15 18 13 -56 21 16 -57 16 10 -68 19 16 -39 18 16 -2______________________________________
The combined miotic agent of the invention was administered to 18 additional subjects. Measurements of IOP were taken on the operated eye (OP) and the fellow (FEL) eye before the operation at surgery (PRE) and 24 hours after the operation (POST). The pupil size was measured at surgery (AT) and 24 hours after surgery (POST). The following Table shows the measurements, the differences (DELTA) and the maximum, minimum and averages of the measurements.
TABLE 2__________________________________________________________________________ Pupil Pupil Delta DeltaPatient Pre-Op Pre-Fel Post-Op Post-Fel AT POST OP FEL__________________________________________________________________________ 1 14 14 13 11 4.5 2 -1 -3 2 22 23 12 26 4 4 -10 3 3 18 18 20 15 5 1.5 2 -3 4 19 19 4 15 4 2.5 -15 -4 5 21 18 25 18 4 1.5 4 0 6 19 18 18 18 3 2 -1 0 7 20 20 21 17 3 2 1 -3 8 16 17 16 14 3.5 2 0 -3 9 18 17 18 12 2.5 2.5 0 -510 16 16 4 16 4 2 -12 011 18 21 5 20 4 2 -13 -112 16 16 18 18 4 2 2 213 13 14 16 16 6 3 3 214 18 20 18 26 3.5 2 0 615 16 16 16 15 4 2.5 0 -116 18 19 15 18 3 2 -3 -117 14 15 18 18 3.5 2 4 318 15 15 12 10 3 2 -3 -5Max. 22 23 25 26 6 4 4 6Min. 13 14 4 10 2.5 1.5 -15 -5Ave. 17.278 17.5556 14.944 16.8333 3.81 2.194 -2.333 -0.72222Std. 2.4688 2.47867 5.8054 4.25994 0.82 0.572 5.9902 3.044871__________________________________________________________________________
The Post-Op IOP is lower than the Pre-Op IOP showing good control. The pupil is still constricted 24 hours later.
A retrospective, clinical study was conducted on pre-operative and post-operative intraocular pressures of patients administered Acetylcholine or Carbachol while undergoing extracapsular, cataract extraction with intraocular lens implantation. The surgery was performed in a similar fashion by one surgeon (the author). Intraocular pressure was measured with the Goldman applanation tonometer the day before surgery during the pre-operative visit. The second intraocular pressure measurement was taken by Goldman applanation tonometer 20-24 hours following surgery at the first post-operative visit.
In the early stages of this retrospective study, it became apparent that post-operative pressure spikes occurring 20-24 hours later were of a major concern. This retrospective study compares the post-operative intraocular pressure (IOP) in 4 groups following standard extracapsular cataract extraction with intraocular lens (ECCE with IOL). The 4 groups consisted of Miochol (acetylcholine chloride) alone, Miochol with 500 mg. Diamox (acetazolamide) given orally at 1800 hours, Miostat (Carbachol) with 500 mg. Diamox given orally at 1800 hours, and fourthly, Miostat alone. FIGS. 2 and 3 show the spiking behavior of the group of patients treated with Miochol with or without Diamox. FIGS. 4 and 5 show that the patients treated with Miostat with or without Diamox had good control of IOP. Surprisingly, the group not receiving Diamox had better control.
The patients given Miochol only had an average pre-operative intraocular pressure of 14.2 and an average post-operative pressure of 26.5. However, 4 of these 11 patients had pressure spikes of over 30, and 1 of 44 mm Hg. The average increase in intraocular pressure was 12.3 mm Hg.
35 patients were given Miochol at the time of surgery with 500 mg. of Diamox orally at 1800 hours on the day of surgery, in an attempt to reduce pressure spikes. The average post-operative pressure was 20.1 with an average increase of 6.8 mm Hg. of pressure. However, in this group, there were 9 of 35 patients with intraocular pressure of above 25 to as high as 42.
38 patients were given Miostat at the time of surgery with Diamox 500 mg. at 1800 hours the day of surgery. The average post-operative intraocular pressure was 16.9, and the average increase in intraocular pressure was 2.3 mm. Only 3 of 38 patients had pressures over 25, the highest being 29. This appeared to be an improvement in control of intraocular pressure 20-24 hours later over both groups of patients using Miochol.
36 patients received only Miostat at surgery with no Diamox given the day of surgery. The average post-operative intraocular pressure was reduced 0.8 mm. Only 1 of 36 patients had a post-operative intraocular pressure of over 25. This group appeared to be clinically at least as well controlled as the Miostat with Diamox group, and certainly superiorly controlled to the Miochol group.
During this retrospective study, 16 known cases of glaucoma were uncovered--an admittedly small group. All glaucoma cases were on medication and felt to be controlled, although 2 patients, 1 in each group, did have a pre-operative pressure of 25. 8 of these patients had been given Miochol at surgery, and 8 had been given Miostat. All of these patients received Diamox 500 mg. at 1800 hours the day of surgery. (a) The surgical technique was the same except a full iridectomy was performed when indicated. (b) Injectable medications at the time of surgery were Garamycin and Celestone. (c) Topical medication used upon completion at surgery were Tobrex, Maxidex, and Betoptic. 500 mg. of Diamox was used orally at 1800 hours the day of surgery in all cases.
FIG. 6 shows the data for the 8 patients who had been given Miochol at surgery. The average pre-operative intraocular pressure was 21, and the average post-operative intraocular pressure was 37, an increase of 16.3 mm. 7 of the 8 patients had intraocular pressures of 30 or over, one patient's pressure spiked to 54 mm.
FIG. 7 shows the data for the 8 patients who had been given Miostat at surgery. Average pre-operative intraocular pressure was 17, and the average post-operative intraocular pressure was the same. Only 2 patients had intraocular pressures above 21, one patient of 26 and one patient of 28. A comparison of the post-operative intraocular pressures in the glaucoma population indicates that there was significant spiking of intraocular pressure 20-24 hours later in the Miochol group compared to the Miostat group of patients.
This retrospective, clinical study of the use of standard ECCE supports the safety and efficacy of the combined miotic agent of the invention. The miotic agent containing both Miochol and Miostat (carbachol 0.01%) appears to be a superior pharmacological agent to one containing Miochol (acetylcholine chloride 1%) in controlling IOP 20-24 hours later, as measured by applanation tonometry. In the routine care of standard ECCE with IOL, Diamox 500 mg. orally at 1800 hours does not seem necessary, if using the miotic agent of the invention containing both Miochol and Miostat. In glaucoma cases, the miotic agent of the invention should be effective in providing quick miosis while controlling post-operative IOP 20-24 hours later.
It is to be realized that only preferred embodiments of the invention have been described and that numerous substitutions, modifications and alterations are permissible without departing from the spirit and scope of the invention as defined in the following claims. | Quick miosis with 24 hour control of intraocular pressure of patients undergoing extracapsular cataract extraction surgery is achieved by applying to the eyes of the patient during surgery acetylcholine as a first miotic agent and carbachol as a second miotic agent. Acetylcholine provides quick miosis while carbachol enhances the miotic effect while providing post-surgery control of intraocular pressure. The two miotic agents can be dissolved in a common saline carrier. The two agents can be combined in a unit dosage package by disposing acetylcholine in powder form in a first compartment and a solution of carbachol in a second compartment. The combined miotic agent of the invention is especially useful when substances which raise IOP such as viscoelastic agents are used during ocular surgery and/or with sensitive patients who enter the surgery with elevated pressure such as those suffering from glaucoma. | 8 |
FIELD OF INVENTION
[0001] The present invention relates to a propylene polymer composition having improved flexural modulus, impact strength and excellent optical properties.
BACKGROUND OF THE INVENTION
[0002] As is known, the isotactic polypropylene is endowed with an exceptional combination of excellent properties which render it suitable for a very great number of uses.
[0003] In order to improve the properties of the isotactic polypropylene the crystallinity of the propylene homopolymer is decreased by copolymerization of the propylene with small quantities of ethylene and/or α-olefins such as 1-butene, 1-pentene and 1-hexene. In this manner one obtains the so called random crystalline propylene copolymers which, when compared to the homopolymer, are essentially characterized by better flexibility and transparency.
[0004] Propylene random copolymers, however, although they have good transparency, do not offer, especially at low temperatures, sufficiently better impact resistance than the homopolymer which can be satisfactory used for the applications listed above.
[0005] It has been known for a long time that the impact resistance of polypropylene can be improved by adding an adequate quantity of elastomeric propylene-ethylene copolymer to the homopolymers by mechanical blending or sequential polymerization. However, this improvement is obtained at the expenses of the transparency of the material.
[0006] To avoid this inconvenient, U.S. Pat. No. 4,634,740 suggests the blending of the polypropylene, in the molten state, with propylene-ethylene copolymers obtained with specific catalysts, and having an ethylene content ranging from 70 to 85% by weight. However, said compositions present transparency values (Haze) substantially comparable to those of the propylene homopolymer. Said patent, therefore, does not teach how to obtain compositions having good transparency.
[0007] EP-A-0557953, describes polyolefin compositions where one obtains a good balance of transparency, stiffness, and impact resistance even at low temperatures, by modifying a crystalline random copolymer of propylene with the proper quantities of a mechanical mixture comprising an elastomeric copolymer and one or more polymers chosen from LLDPE, LDPE and HDPE.
[0008] WO 01/92406 describes a propylene polymer composition comprising (percent by weight):
A) from 70 to 90%, of a random copolymer of propylene with ethylene, containing from 1 to 6%, of ethylene, having a content of fraction insoluble in xylene at room temperature of not less than 93; B) from 10% to 30%, of a copolymer of propylene with ethylene, containing from 8 to 18%, of ethylene;
wherein the ratio (B)/C 2 B of the percent by weight of (B), with respect to the total weight of (A) and (B), to the percent by weight of ethylene in (B), with respect to the total weight of (B), represented in the above formula by C 2 B , is 2.5 or lower. The MFR L ranges from 0.5 to 50 g/10 min. This composition shows a good transparency but it can be improved by fine tuning the variables of the composition.
SUMMARY OF THE INVENTION
[0011] The applicant found a propylene polymer composition having a particular balance among the various parameter so that to obtain improved values of flexural modulus, good values of haze and good resistance to impact.
[0012] Thus one object of the present invention is a propylene polymer composition comprising:
A) from 70 wt % to 95 wt %, preferably from 75 wt % to 93 wt %, more preferably from of 80 wt % to 91 wt % of a random copolymer of propylene with ethylene, containing from 3.5 wt % to 6.5 wt %, preferably from 4.0 wt % to 5.5 wt %, of ethylene derived units, having a content of fraction soluble in xylene at 25° C. comprised between 7.1 wt % and 11.2 wt %; preferably from 8.3 wt % to 10.2 wt %; B) from 5 wt % to 35 wt %, preferably from 8 wt % to 25 wt %, more preferably from 11 wt % to 14 wt % of a copolymer of propylene with ethylene, containing from 8.5 wt % to 17.0 wt %, preferably from 8.8 wt % to 14.7 wt %, of ethylene derived units; the sum A+B being 100;
wherein the melt flow rate ,MFR. (ISO 1133 (230° C., 2.16 kg).) ranges from 0.6 g/10 min to 20.2 g/10 min; preferably from 0.8 g/10 min to 5.0 g/10 min; more preferably from 1.0 g/10 min to 3.2 g/10 min;
DETAILED DESCRIPTION OF THE INVENTION
[0015] The term “copolymer” includes polymers containing only propylene and ethylene.
[0016] The present invention is preferably endowed with one or more of the following features:
Intrinsic Viscosity [η] of the fraction (of the overall composition) soluble in xylene at 25° C. ranges from 1 to 4.5, more preferably from 1.3 to 4.0 dl/g. the fraction (of the overall composition) soluble in xylene at 25° C. ranges from 10.3 wt % to 18.5 wt % a Flexural Modulus of the unucleated composition higher than 700 MPa; Haze of the unucleated composition measured on 50 μm film lower than 4.1% preferably lower than 3.2% more preferably lower than 2.8%.
[0021] The compositions of the present invention can be prepared by sequential polymerization in at least two polymerization steps. Such polymerization is carried out in the presence of stereospecific Ziegler-Natta catalysts. An essential component of said catalysts is a solid catalyst component comprising a titanium compound having at least one titanium-halogen bond, and an electron-donor compound, both supported on a magnesium halide in active form. Another essential component (co-catalyst) is an organoaluminum compound, such as an aluminum alkyl compound.
[0022] An external donor is optionally added.
[0023] The catalysts generally used in the process of the invention are capable of producing polypropylene with an Isotacticity Index greater than 90%, preferably greater than 95%.
[0024] Catalysts having the above mentioned characteristics are well known in the patent literature; particularly advantageous are the catalysts described in U.S. Pat. No. 4,399,054 and European patent 45977. Other examples can be found in U.S. Pat. No. 4,472,524.
[0025] The solid catalyst components used in said catalysts comprise, as electron-donors (internal donors), compounds selected from the group consisting of ethers, ketones, lactones, compounds containing N, P and/or S atoms, and esters of mono- and dicarboxylic acids.
[0026] Particularly suitable electron-donor compounds are 1,3-diethers of formula:
[0000]
[0000] wherein R I and R II are the same or different and are C 1 -C 18 alkyl, C 3 -C 18 cycloalkyl or C 7 -C 18 aryl radicals; R III and R IV are the same or different and are C 1 -C 4 alkyl radicals; or are the 1,3-diethers in which the carbon atom in position 2 belongs to a cyclic or polycyclic structure made up of 5, 6, or 7 carbon atoms, or of 5-n or 6-n′ carbon atoms, and respectively n nitrogen atoms and n′ heteroatoms selected from the group consisting of N, O, S and Si, where n is 1 or 2 and n′ is 1, 2, or 3, said structure containing two or three unsaturations (cyclopolyenic structure), and optionally being condensed with other cyclic structures, or substituted with one or more substituents selected from the group consisting of linear or branched alkyl radicals; cycloalkyl, aryl, aralkyl, alkaryl radicals and halogens, or being condensed with other cyclic structures and substituted with one or more of the above mentioned substituents that can also be bonded to the condensed cyclic structures; one or more of the above mentioned alkyl, cycloalkyl, aryl, aralkyl, or alkaryl radicals and the condensed cyclic structures optionally containing one or more heteroatoms as substitutes for carbon or hydrogen atoms, or both.
[0027] Ethers of this type are described in published European patent applications 361493 and 728769. Representative examples of said dieters are 2-methyl-2-isopropyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-cyclopentyl-1,3-dimethoxypropane, 2-isopropyl-2-isoamyl-1,3-dimethoxypropane, 9,9-bis (methoxymethyl) fluorene.
[0028] Other suitable electron-donor compounds are phthalic acid esters, such as diisobutyl, dioctyl, diphenyl and benzylbutyl phthalate.
[0029] The preparation of the above mentioned catalyst components is carried out according to various methods.
[0030] For example, a MgCl 2 ·nROH adduct (in particular in the form of spheroidal particles) wherein n is generally from 1 to 3 and ROH is ethanol, butanol or isobutanol, is reacted with an excess of TiCl 4 containing the electron-donor compound. The reaction temperature is generally from 80 to 120° C. The solid is then isolated and reacted once more with TiCl 4 , in the presence or absence of the electron-donor compound, after which it is separated and washed with aliquots of a hydrocarbon until all chlorine ions have disappeared.
[0031] In the solid catalyst component the titanium compound, expressed as Ti, is generally present in an amount from 0.5 to 10% by weight. The quantity of electron-donor compound which remains fixed on the solid catalyst component generally is 5 to 20% by moles with respect to the magnesium dihalide.
[0032] The titanium compounds which can be used for the preparation of the solid catalyst component are the halides and the halogen alcoholates of titanium. Titanium tetrachloride is the preferred compound.
[0033] The reactions described above result in the formation of a magnesium halide in active form. Other reactions are known in the literature, which cause the formation of magnesium halide in active form starting from magnesium compounds other than halides, such as magnesium carboxylates.
[0034] The active form of magnesium halide in the solid catalyst component can be recognized by the fact that in the X-ray spectrum of the catalyst component the maximum intensity reflection appearing in the spectrum of the nonactivated magnesium halide (having a surface area smaller than 3 m 2 /g) is no longer present, but in its place there is a halo with the maximum intensity shifted with respect to the position of the maximum intensity reflection of the nonactivated magnesium dihalide, or by the fact that the maximum intensity reflection shows a width at half-peak at least 30% greater than the one of the maximum intensity reflection which appears in the spectrum of the nonactivated magnesium halide. The most active forms are those where the above mentioned halo appears in the X-ray spectrum of the solid catalyst component.
[0035] Among magnesium halides, the magnesium chloride is preferred. In the case of the most active forms of magnesium chloride, the X-ray spectrum of the solid catalyst component shows a halo instead of the reflection which in the spectrum of the nonactivated chloride appears at 2.56 Å.
[0036] The Al-alkyl compounds used as co-catalysts comprise the Al-trialkyls, such as Al-triethyl, Al-triisobutyl, Al-tri-n-butyl, and linear or cyclic Al-alkyl compounds containing two or more Al atoms bonded to each other by way of O or N atoms, or SO 4 or SO 3 groups.
[0037] The Al-alkyl compound is generally used in such a quantity that the Al/Ti ratio be from 1 to 1000.
[0038] The electron-donor compounds that can be used as external donors include aromatic acid esters such as alkyl benzoates, and in particular silicon compounds containing at least one Si-OR bond, where R is a hydrocarbon radical.
[0039] Examples of silicon compounds are (tert-butyl) 2 Si (OCH 3 ) 2 , (cyclohexyl) (methyl) Si (OCH 3 ) 2 , (phenyl) 2 Si (OCH 3 ) 2 and (cyclopentyl) 2 Si (OCH 3 ) 2 . 1,3-diethers having the formulae described above can also be used advantageously. If the internal donor is one of these dieters, the external donors can be omitted.
[0040] Preferably said polypropylene composition being obtainable with a polymerization process carried out in the presence of a catalyst system comprising the product obtained by contacting (a) a solid catalyst component having preferably average particle size ranging from 15 to 80 μm comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least two electron donor compounds one of which being present in an amount from 40 to 90% by mol with respect to the total amount of donors and selected from succinates and the other being selected from 1,3 diethers, (b) an aluminum hydrocarbyl compound and optionally (c) an external electron donor compound.
[0041] As previously said, the polymerization process can be carried out in at least two sequential steps, wherein components A) and B) are prepared in separate subsequent steps, operating in each step, except the first step, in the presence of the polymer formed and the catalyst used in the preceding step. The catalyst is generally added only in the first step, however its activity is such that it is still active for all the subsequent step(s).
[0042] Component A) is preferably prepared before component B).
[0043] The regulation of the molecular weight is carried out by using known regulators, hydrogen in particular.
[0044] By properly dosing the concentration of the molecular weight regulator in the relevant steps, the previously described MFR and [η] values are obtained.
[0045] The whole polymerization process, which can be continuous or batch, is carried out following known techniques and operating in liquid phase, in the presence or not of inert diluent, or in gas phase, or by mixed liquid-gas techniques. It is preferable to carry out the propylene copolymerization step(s) for preparation of component A) in liquid propylene as diluent, and the other polymerization step(s) in gas phase. Generally there is no need for intermediate steps except for the degassing of unreacted monomers.
[0046] Reaction time, pressure and temperature relative to the two steps are not critical, however it is best if the temperature is from 20 to 100° C. The pressure can be atmospheric or higher.
[0047] The catalysts can be pre-contacted with small amounts of olefins (prepolymerization).
[0048] The compositions of the present invention can also be obtained by preparing separately the said components A) and B) by operating with the same catalysts and substantially under the same polymerization conditions as previously explained (except that a wholly sequential polymerization process will not be carried out, but the said components and fractions will be prepared in separate polymerization steps) and then mechanically blending said components and fractions in the molten or softened state. Conventional mixing apparatuses, like screw extruders, in particular twin screw extruders, can be used.
[0049] The compositions of the present invention can also contain additives commonly employed in the art, such as antioxidants, light stabilizers, heat stabilizers, nucleating agents, colorants and fillers. In particular, the addition of nucleating agents brings about a considerable improvement in important physical-mechanical properties, such as Flexural Modulus, Heat Distortion Temperature (HDT), tensile strength at yield and transparency.
[0050] Typical examples of nucleating agents are the p-tert.-butyl benzoate and the 1,3- and 2,4-dibenzylidenesorbitols.
[0051] The nucleating agents are preferably added to the compositions of the present invention in quantities ranging from 0.05 to 2% by weight, more preferably from 0.1 to 1% by weight with respect to the total weight.
[0052] The addition of inorganic fillers, such as talc, calcium carbonate and mineral fibers, also brings about an improvement to some mechanical properties, such as Flexural Modulus and HDT. Talc can also have a nucleating effect.
[0053] The compositions of the present invention are particularly suited for the production of injection molding articles in particular medical articles in view of the transparency of the composition that is maintained even after the sterilization at high temperature.
[0054] The particulars are given in the following examples, which are given to illustrate, without limiting, the present invention.
EXAMPLES
[0055] Melt Flow Rate
[0056] Determined according to ISO 1133 (230° C., 2.16 kg).
[0057] Ethylene Content of the Polymers (C2 Content)
[0058] Ethylene content has been determined by IR spectroscopy.
[0059] The spectrum of a pressed film of the polymer is recorded in absorbance vs. wavenumbers (cm −1 ). The following measurements are used to calculate C2 content:
a) Area (A t ) of the combination absorption bands between 4482 and 3950 cm −1 which is used for spectrometric normalization of film thickness. b) Area (A c2 ) of the absorption band due to methylenic sequences (CH 2 rocking vibration) after a proper digital subtraction of an isotactic polypropylene (IPP) reference spectrum. The range 660 to 790 cm −1 .
[0062] Molar Ratios of the Feed Gases
[0063] Determined by gas-chromatography.
[0064] Samples for the Mechanical Analysis
[0065] Samples have been obtained according to ISO 294-2
[0066] Flexural Modulus
[0067] Determined according to ISO 178.
[0068] Haze (50 μm Film)
[0069] Preparation of the Film Specimens
[0070] A film with a thickness of 50 μm is prepared by extruding the polymer in a single screw Collin extruder (length/diameter ratio of screw: 25) at a film drawing speed of 7 m/min. and a melt temperature of 210-250° C.
[0071] Haze (on 50 μm Film):
[0072] Determined on 50 μm thick cast films of the test composition. The measurement was carried out on a 50×50 mm portion cut from the central zone of the film.
[0073] The instrument used for the test was a Gardner photometer with Haze-meter UX-10 equipped with a G.E. 1209 lamp and filter C. The instrument calibration was made by carrying out a measurement in the absence of the sample (0% Haze) and a measurement with intercepted light beam (100% Haze).
[0074] Melting Temperature, Melting Enthalpy and Crystallization Temperature
[0075] Determined by differential scanning calorimetry (DSC). A sample weighting 6±1 mg, is heated to 220±1° C. at a rate of 20° C./min and kept at 220±1° C. for 2 minutes in nitrogen stream and it is thereafter cooled at a rate of 20° C./min to 40±2° C., thereby kept at this temperature for 2 min to crystallise the sample. Then, the sample is again fused at a temperature rise rate of 20° C./min up to 220° C.±1. The melting scan is recorded, a thermogram is obtained, and, from this, melting temperatures is read.
[0076] Xylene Soluble and Insoluble Fractions at 25° C. (Room Temperature)
[0077] 2.5 g of polymer and 250 cm 3 of xylene are introduced in a glass flask equipped with a refrigerator and a magnetical stirrer. The temperature is raised in 30 minutes up to the boiling point of the solvent. The so obtained clear solution is then kept under reflux and stirring for further 30 minutes. The closed flask is then kept for 30 minutes in a thermostatic water bath at 25° C. for 30 minutes. The so formed solid is filtered on quick filtering paper. 100 cm 3 of the filtered liquid is poured in a previously weighed aluminum container which is heated on a heating plate under nitrogen flow, to remove the solvent by evaporation. The container is then kept in an oven at 80° C. under vacuum until constant weight is obtained. The weight percentage of polymer soluble in xylene at room temperature is then calculated. The percent by weight of polymer insoluble in xylene at room temperature is considered the Isotacticity Index of the polymer.
[0078] Intrinsic Viscosity (I.V.)
[0079] Determined in tetrahydronaphthalene at 135° C.
[0080] IZOD Impact Strength
[0081] Determined according to ISO 180/1A
[0082] Hexane Soluble Fraction
[0083] 10 g of material are placed in a 250 ml glass flask with a ground-glass neck. 100 ml of hexane are added and let boil under reflux condenser for 4 hours, stirring constantly. After cooling in iced water the solution is filtered through a sintered-glass filter maintaining the solution at 0° C. 20 ml of the filtrate is evaporated in a tared glass dish. The residuate is dried in an oven at 100° C. to 105° C. for 1 hour then weighted.
[0084] Sterilization Procedure
[0085] The sample is placed in a steam sterilization autoclave Systec DX-65 set at 121 degree Celsius and 2.1 bar of nitrogen internal pressure. After 20 minutes of treatment in the autoclave, the item is let cool down to room temperature and conditioned at room temperature for 48 hours before testing.
[0086] Preparation of Solid Catalyst Component A
[0087] Into a 500 mL four-necked round flask, purged with nitrogen, 250 mL of TiCl 4 were introduced at 0° C. While stirring, 10.0 g of microspheroidal MgCl 2 *2.8C 2 H 5 OH (prepared according to the method described in ex.2 of U.S. Pat. No. 4,399,054) and 7.4 mmol of 9,9-bis(methoxymethyl)fluorene were added. The temperature was raised to 100° C. and maintained for 120 min. Then, the stirring was discontinued, the solid product was allowed to settle and the supernatant liquid was siphoned off. Then 250 mL of fresh TiCl 4 were added. The mixture was reacted at 120° C. for 60 min and, then, the supernatant liquid was siphoned off. The solid was washed six times with anhydrous hexane (6×100 mL) at 60° C. Finally, the solid was dried under vacuum and analyzed. The resulting solid catalyst component contained: Ti=3.5% by weight, 9,9-bis(methoxymethyl)fluorene=18.1% by weight.
[0088] Preparation of Solid Catalyst Component B
[0089] Into a 500 mL four-necked round flask, purged with nitrogen, 250 mL of TiCl 4 were introduced at 0° C. While stirring, 10.0 g of microspheroidal MgCl 2 ·2.1C 2 H 5 OH having average particle size of 47 μm (prepared according to the method described in ex.2 of U.S. Pat. No. 4,399,054) an amount of diethyl 2,3-diisopropylsuccinate such as to have a Mg/succinate molar ratio of 15 were added. The temperature was raised to 100° C. and kept at this value for 60 min. After that the stirring was stopped, the liquid was siphoned off. After siphoning, fresh TiCl 4 and an amount of 9,9-bis(methoxymethyl)fluorene such as to have a Mg/diether molar ratio of 30 were added. Then the temperature was raised to 110° C. and kept for 30 minutes under stirring. After sedimentation and siphoning at 85° C., fresh TiCl4 was added. Then the temperature was raised to 90° C. for 15 min. After sedimentation and siphoning at 90° C. the solid was washed six times with anhydrous hexane (6×100 ml) at 60° C.
[0090] Preparation of the Catalyst System
[0091] Before introducing it into the polymerization reactors, the solid catalyst components A and B described above are contacted at 15° C. for 30 minutes with aluminum-triethyl (TEAL) and cyclohexyl-methyl-dimethoxysilane (CHMMS) used as external donor
Polymerization Examples 1 and 2
[0092] The polymerization runs were conducted in continuous in a series of two reactors equipped with devices to transfer the product from one reactor to the one immediately next to it. The first reactor is a polymerisation apparatus as described in EP 1 012 195.
[0093] The catalyst is sent to the polymerisation apparatus that comprises two interconnected cylindrical reactors, riser and downcomer. Fast fluidisation conditions are established in the riser by recycling gas from the gas-solid separator. The obtained product is then feed to a fluid bed gas phase reactor. Hydrogen was used as molecular weight regulator.
[0094] The gas phase (propylene, ethylene and hydrogen) is continuously analyzed via gas-chromatography.
[0095] At the end of the run the powder was discharged, dried in an oven at 60° C. under a nitrogen flow and pelletized. The polymerization parameters are reported in table 1.
[0000]
TABLE 1
Example
1
2
Solid catalyst component
A
B
Component A)
TEAL/external donor
wt/wt
6
6
TEAL/catalyst
wt/wt
7.5
7.5
Temperature
° C.
72
73
Pressure
bar-g
27
28
Split holdup
riser
wt %
38
34
downcomer
wt %
62
66
C 3 riser
mole %
76
76.8
C 2 riser
mole %
2.5
2.9
H 2 /C 3 riser
mol/mol
0.002
0.009
C 2 /(C 2 + C 3 )Riser
mol/mol
0.032
0.037
Component B (gas phase reactor)
Temperature
° C.
80
75
Pressure
Bar-g
15
13
C 2 /C 2 + C 3
mol/mol
0.085
0.0082
H 2 /C 2 −
mol/mol
0.15
0.283
C2 − = ethylene; C3 − = propylene; H2 = hydrogen
Comparative Example 2
[0096] Comparative example 2 is example 1 of WO 01/92406.
[0000]
TABLE 2
analysis of the polymer
Comparative
Ex
Ex 1
EX2
example 2
Component A
MFR
g/10′
1,2
2.2
1.7
C2
%
4.8
4.5
2.5
XS
%
9.2
11.7
5.3
Component B
Amount comp B
wt %
11.4
13
19
C2 content
wt %
9.0
9.1
nm
Composition
C2 content
wt %
5.2
5.1
5.3
Xylene Solubles
%
14.4
13.0
13.4
XSIV
dl/g
1.42
1.26
3.6
Characterization of
composition
Melt Flow Rate
g/10′
1.1
1.73
1.30
Flexural Modulus
MPa
711
716
715
Flexural Modulus
MPa
776
793
nm
after ster.
Izod Impact 23° C.
kJ/m2
38,9
21,0
nm
Izod Impact 0° C.
kJ/m2
7,6
6,3
nm
Izod Impact −20° C.
kJ/m2
3,4
2,4
nm
Hexane extr. on
wt %
2.4
3.2
nm
pellets
Haze on 50 cast film
%
2,0
2,0
8.2
Haze on 50 μmm
%
15,8
16,2
nm
cast film after ster.
C2 = ethylene; C3 = propylene; nm = not measured
[0097] From table 2 clearly results that the composition according to the present invention shows an improved haze on film by maintaining the same flexural modulus and the same total content of ethylene derived units (5.3 vs 5.2). | Propylene polymer compositions comprising:
A) from 70 wt % to 95 wt %, of a random copolymer of propylene with ethylene, containing from 3.5 wt % to 6.5 wt % of ethylene derived units, having a content of fraction insoluble in xylene at 25° C. of not less than 93 wt %; B) from 5 wt % to 35 wt %, of a copolymer of propylene with ethylene, containing from 8.5 Wt % to 17.0 wt % of ethylene derived units; the sum A+B being 100; the melt flow rate ,MFR (ISO 1133 (230° C., 2.16 kg) ranges from 0.6 g/10 min to 20.2 g/10 min. | 2 |
This application is a continuation of application Ser. No. 08/151,043 filed Nov. 12, 1993, now abandoned, which is a continuation of application Ser. No. 07/704,214, filed May 22, 1991, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a pattern developing method and, more particularly, to outputting method and apparatus in which character symbol patterns corresponding to information comprising character symbol codes and their decoration data which have been supplied are generated and the character symbol patterns are sequentially developed at the relevant positions in an outputting memory.
2. Related Background Art
In recent years, due to the development of a DTP (Desk Top Publishing), a more complicated print format is required and many characters of different sizes are needed.
To individually prepare images of tens of kinds of character sizes for this purpose, a memory of an extremely large capacity is necessary, so that an efficiency is low. To solve such a drawback, in recent years, there is used a method whereby an outline or a frame of a character is detected as a set of numerical value coordinates and is developed by a numerical value arithmetic operation as necessary and is converted into an image and is generated.
Such character data is called an outline font, a vector font, or the like. Generally, however, it takes a fairly long calculating time to develop from the vector data to the image.
In general, therefore, a method called a character cache in which the image of the character which has been developed is temporarily stored and is again used is commonly used.
In the character cache mechanism, however, since it is necessary to store image data, a necessary memory capacity is large. Therefore, in the actual system, many characters cannot be stored.
On the other hand, even if the memory capacity is sufficiently large, retrieving and updating efficiencies of the cache deteriorate. Therefore, it is improper to set the memory capacity to a remarkably large capacity.
Generally, type styles and sizes which are used are different every user or every job. Therefore, in the character cache mechanism of a printer (laser beam printer or the like) which is commonly used by a few host machines, the character cache is updated for a period of time when outputs of a plurality of users are alternately generated. For the user whose printing order has come, a hit ratio of the character patterns registered in the cache memory decreases, so that the effect of the character cache mechanism is not obtained.
As mentioned above, the memory assigned to the character cache is not effectively used and an efficiency is low. Particularly, such a phenomenon is remarkable in Japanese having a large number of characters.
In an image forming apparatus which is frequently accessed from a plurality of users or jobs, it will be understood from the above description that the ordinary character font cache mechanism is not so effective in terms of an amount of consumption of the memory.
SUMMARY OF THE INVENTION
The invention is made in consideration of the above conventional technique and it is an object of the invention to provide outputting method and apparatus which can efficiently execute a developing process of character symbol patterns for an outputting memory.
A pattern developing method of the invention to solve the foregoing problems has the following construction. That is,
in a pattern developing method whereby character symbol patterns corresponding to information comprising character symbol codes and their decoration data which have been supplied are generated and the character symbol patterns are sequentially developed at relevant positions in an outputting memory, there are provided outputting method and apparatus comprising: discriminating means which is constructed in a manner such that when a character symbol pattern corresponding to target information is developed into the outputting memory, a check is made to see if the same pattern as the target character symbol pattern has already been developed in the outputting memory or not; and copying means for copying the same pattern to the developing position of the target character symbol pattern when it is discriminated by the discriminating means that the same pattern has already been developed.
According to the invention, there are provided outputting method and apparatus in which when it is determined that the same pattern as a character symbol pattern corresponding to target information has already been developed in an outputting memory before then, such a character pattern is not newly generated but the same pattern is copied to a developing position of the target character symbol pattern.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block constructional diagram of a laser beam printer of an embodiment;
FIG. 2 is a diagram showing an example of a character attribute area in the embodiment;
FIG. 3 is a flowchart for a developing process of a character pattern in an apparatus of the embodiment;
FIG. 4 is a diagram showing the relation between a page buffer and a character attribute area in the embodiment;
FIG. 5 is a diagram showing a character attribute area in the second embodiment;
FIG. 6 is a flowchart showing changed portions of a character pattern developing process in the second embodiment;
FIG. 7 is a diagram showing a character attribute area in the third embodiment;
FIG. 8 is a flowchart showing changed portions of a character pattern developing process in the third embodiment;
FIG. 9 is a flowchart showing changed portions of a character pattern developing process in the fourth embodiment; and
FIG. 10 is a flowchart in the case where a cache memory is added to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of the invention will be described in detail hereinbelow with reference to the drawings. The invention can be applied to an apparatus or a system or can be also accomplished by supplying a program to an apparatus or a system.
FIG. 1 shows a block constructional diagram of an image processing section of a laser beam printer of an embodiment.
In the diagram, reference numeral 10 denotes a CPU to control a whole apparatus; 11 a ROM in which operation processing procedures (flowcharts of FIGS. 3, 6, and 8) of the CPU 10 have been stored; 12 a, RAM which is used as a work area of the CPU 10 and has a page buffer 12a to develop image data of one page and a character attribute area 12b as shown in the diagram; 13 a font ROM in which vector font data (data of the coordinate format) has been stored; 14 a video interface (video I/F) to supply the data which has been developed in the page buffer 12a to a printer engine section (not shown) as a video signal; and 200 to 203 input/output units (hereinafter, abbreviated to I/O) to receive print data from an outside. A plurality of host computers can be connected as shown in the diagram. Each of the above component elements is electrically connected to a system bus 100 (comprising a data bus, an address bus, and a control bus).
In the above construction, the print data which has been received through the I/O is analized and a character pattern is generated in accordance with a designated control command and developed into the page buffer 12a. After the image data of one page was developed into the page buffer 12a, the image data is sequentially supplied to the printer engine through the video I/F 14. It is now assumed that the operation of the printer engine is executed in accordance with a well-known electrophotograph technique. The operation is not described in detail here.
FIG. 2 shows the content in the character attribute area 12b of the embodiment.
Among the character patterns to be developed into the page buffer 12a, attribute information of characters which are not yet drawn is stored into the character attribute area 12b. The diagram shows the content of the attribute information corresponding to one of those characters.
As shown in the diagram, one attribute information includes: a code 20 to store a character code; information 21 regarding a size of character and an attribute such as a tilted type and the like; a coordinate position 22 (X and Y coordinates in the page buffer 12a or an address and bit position information) in the page buffer 12a of the character pattern; and size information 23 in the vertical and lateral directions of a rectangular area of the character pattern.
FIG. 4 shows-an example of a mapping of the page buffer 12a.
The address continuously increases in the X direction and the address increases by "K" at a time in the Y direction. Bits in a word are arranged in a line in the lateral direction. For instance, in the case of forming an image for a printer to output the image onto a paper of the A4 size at a resolution of 300 d.p.i., coordinate points such as X≅2500 and Y≅3600 are necessary. Therefore, assuming that one word consists of 16 bits, a value of K is set to about 160.
Data of a rectangular area is transferred on a bit unit basis instead of a simple word unit basis, so that a bit shift or the like is needed. However, in the recent CPU, a command for such a bit shift or the like is supported and the data can be processed at a high speed. A high-speed process can be realized by adding a hardware for a graphic process or a special LSI as necessary.
A procedure for drawing a character in the embodiment will now be described with reference to a flowchart of FIG. 3.
First, in step S1, a check is made to see if a character of the same character code and the same attribute (including the size) as those of a character to be drawn (developed) has already been developed in the page buffer 12a or not by retrieving the character attribute area 12b.
If the character having the same character code and the same attribute exists, step S2 follows and the coordinates of such a character are calculated. Step S3 then follows and an area to be transferred is determined on the basis of the size information 23 in the vertical and lateral directions of the rectangular area of the character pattern. After that, in step S4, the pattern of the rectangular image obtained at the developing position (printing position) of the target character is transferred.
In the page buffer 12a of the construction as shown in FIG. 4, the addresses in the X direction are continuous. Even in the case of transferring by a hardware or by a software, the construction is very simple. However, the address in the Y direction is added on a predetermined value unit basis. According to the method of the invention, a common value can be used as an addition address value in the Y direction because the transfer destination side of the data transfer and the data transferring side are in the same page memory, so that the construction is simple. However, different addition values are needed in the case of the conventional character cache mechanism.
If it is determined in step S1 that the target character is not yet registered in the character attribute area 12b, that is, it is not yet cached, step S5 follows and the printing position of the target character in the page buffer 12a is calculated. In step S6, a check is made to see if another figure has been drawn in the rectangular area in the page buffer 12a calculated from the attribute data of the designated character or not. If such a figure has already existed at the position where the data is newly printed (in the case of collision), a normal character image cannot be transferred at a stage at which the same character will be developed later. In such a case, therefore, the processing routine advances to step S9 and the character pattern is merely drawn at the calculated position.
If any other figure doesn't exist in the developing area of the target character, namely, if the character pattern can be used as an image of a character cache, step S7 follows and the vector data is selected on the basis of the character code and the attribute data and the character is drawn in the page memory (the same as step S9). In step S8, further, the attribute data is registered into each area in the character attribute area 12b.
The laser beam printer in the embodiment draws not only characters but also graphics. If the necessity of the writing operation has occurred in the rectangular area registered in the character attribute area 12b when a graphic pattern is drawn, the image of the character is broken. In such a case, by eliminating the information regarding such a character from the area 12b, the transfer of the wrong image is prevented. In this case, the collision of the character and the figure is detected by comparing the position of the image of the character of the attribute data with the rectangular area instead of the inside of the page buffer 12a. This is because in the case where a character pattern has been printed onto a blank portion in the rectangular area, the collision cannot be detected in the page memory.
A graphic process such as drawing of a curve, painting, or the like can be finally dissolved until a combination of drawing of straight lines. By comparing the straight line and the rectangle, the collision of the figure and the character is detected.
Second Embodiment!
In the foregoing first embodiment, in the case where after a charachter had been drawn, a graphic pattern has been overwritten onto the rectangular area of the character, the character is deleted from the storage area of the character attribute, so that the cache effect becomes invalid. That is, if the character is again needed, it is necessary to develop from the vector data to the image.
In the second embodiment, therefore, a plurality of coordinate positions 22 are prepared in the character attribute area 12b. Even if one character has collided with the graphic pattern and has been deleted, the data of another image area construction is used to thereby continue the cache effect.
In the above case, the character attribute area 12b has a content as shown in FIG. 5 In the diagram, four coordinate positions 22-1 to 22-4 are provided. However, the number of position data can be varied within an arbitrary range.
Among the four position data, as position data which doesn't designate a character in the page buffer 12a, special coordinate values or the like which actually cannot exist are stored, thereby enabling such position data to be distinguished.
In the above case, the process in step S4 in the printing procedure of FIG. 3 is changed as shown in FIG. 6.
In step S61, a check is made to see if another figure exists at the developing position (printing position) of the target character or not. If the presence of another figure has been detected, it is meaningless to register the development coordinates of the target character. Therefore, in this case, the processing routine advances to step S62 and the pattern of the rectangular area stored at a coordinate position 22-i in the character attribute area 12b is transferred to the developing position of the target character. At this time, since another figure exists near the developing position of the target character, when the character pattern is developed at such a position, the OR is calculated and the character pattern is developed. This is because unless otherwise, another figure at that position is deleted.
On the other hand, if the existence of another figure is not detected at the developing position (printing position) of the target character in step S61, step S63 follows and a process similar to step S62 is executed. In this case, there is no need to calculate the OR. After that, step S64 follows and a check is made to see if in the table of the target character in the character attribute area 12b, an idle pointer--which indicates nothing exists at the coordinate positions 22-1 to 22-4 or not. If there is no idle pointer, the processing routine if finished. If an idle pointer exists, step S65 follows and the coordinates of the development destination side of the target character are registered to the idle pointer.
By the above processes, even if a plurality of data of character images have been prepared and even if either one of the character images has collided with another figure, the cache effect is continued.
In this case, if all of the coordinate position areas 22-1 to 22-4 are empty, the whole attribute data of the characters is eliminated from the character attribute area 12b.
By the above construction, a ratio at which the cache effect of the character is continued rises and the cache can be efficiently used.
Third embodiment !
Generally, a probability such that a character drawn collides with another figure drawn and cannot be used as a cache image is higher for a character which has been drawn at the initial stage. Therefore, as a third embodiment, there is shown an example in which the position data of a character is sequentially replaced to the coordinates of the new character, thereby maintaining the effect of the cache.
In the third embodiment, a pointer to update the address is further added to the attribute data of the character. FIG. 7 shows a structure of the attribute data in the character attribute area 12b in the third embodiment.
One of a plurality of coordiate position data is indicated by a pointer 26 to update the address. In the third embodiment, if the pointer of the address in the page buffer in which the character pattern has been stored is set to a value which is the power of 2, the system is simplified. In the third embodiment, therefore, four coordinate positions 22-0 to 22-3 shown in the diagram are set and a counter of two bits is used as a pointer 26.
Each time the cached character is used, a check is made to see if the new character drawn has collided with another figure or not (corresponding to step S6 in FIG. 3 and step S61 in FIG. 6). If NO, the coordinates of the character image indicated by the pointer 26 are updated to the coordinates of the character which has newly been drawn and the value of the pointer 26 is counted up.
In the case of the third embodiment, the process in step S4 in FIG. 3 is likewise changed as shown in FIG. 8.
In step S81, the coollision is detected and a check is made to see if the developing position area of the target character can be registered as a character image on the transferring side or not. In steps S82 and S83, the rectangular area of the character image is transferred to the developing position (printing position). In the case where the newly developed character is transferred as a source of the character image, step S84 follows and the coordinate position which has at present been developed is registered into the coordinate position 22-i indicated by the pointer 26. In the next step S85, the value of the pointer 26 is counted up so as to indicate the new coordinate position and is updated by the following process.
The address registered as a character cache in the page memory is sequentially updated by the above construction, thereby maintaining the character image. Thus, a probability such that the cache is eliminated further decreases.
Fourth embodiment!
Generally, when a graphic pattern is drawn, it takes a long arithmetic operating time to detect the collision with the rectangular area of a character image. Therefore, if a character is first drawn (developed) and a graphic pattern is finally drawn to thereby omit the collision detecting step, the processing speed is remarkably improved. In the fourth embodiment, it is possible to select whether the collision detecting step is executed or not by a command given from an external apparatus such as a computer or the like.
Practically speaking, a variable F indicating whether the collision detection is performed or not is provided in a predetermined address in the RAM. A value of the variable F is set to ON or OFF by an ON command of the collision detection and an OFF command of the collision detection which are supplied from the input sections shown by the I/O units 200 to 203 in FIG. 1.
According to the above process, the collision detecting processes shown in step S6 in FIG. 3, step S61 in FIG. 6, step S81 in FIG. 8,. and the like are changed as shown in FIG. 9. That is, in the case where the variable F is set to OFF and the collision detecting routine is not used, a processing routine B corresponding to the case where no collision occurs is always executed.
When the variable F is set to ON, that is, if the collision detecting process is executed, the ordinary collision detecting routine is performed. The occurrence of the collision is discriminated and either one of the process B in the case where no collision occurs and the process C in the case where the collision has occurred is executed.
There is no need to detect the collision under a special condition such that a character is printed after all of the figures were drawn or that, contrarily, a figure is drawn after all of the characters were printed or the like. Therefore, as a default value of the variable F, ON is selected and, ordinarily, the collision detecting mechanism is always made operative.
The processing speed of the image forming system can be improved by the fourth embodiment.
According to the embodiment, the memory capacity can be saved and a cache having a high executing performance can be formed. Since it is sufficient to use only the storage area of the character attribute as a use area in the memory, an overflow of the cache hardly occurs in such a page. The producing speed of the character at the first time and the transferring effect of the character can be improved.
In the ordinary character cache mechanism, a rectangular area is provided in the character cache and a character image is first drawn there and, after that, the image is transferred to the print area in the page memory. That is, this is because it takes an additional time corresponding to only such a transferring time according to conventional method.
As described above, according to the invention, to process to develop the character symbol pattern into the outputting memory can be efficiently executed.
It is also possible to combine the ordinary cache memory and the invention and to store characters whose addresses are frequently updated, namely, whose use frequencies are high in the invention into the cache memory.
In such a case, retrieval frequency data in step S1 in FIG. 3 is stored in the RAM 12 in FIG. 1 or the like. When the use frequency is relatively high, it is registered into a cache memory (not shown) (provided in, for example, the RAM 12 in FIG. 1). With the above construction, only the necessary minimum number of patterns whose appearing frequencies are very high can be registered into the cache memory. The patterns in the outputting memory other than those patterns are used. Therefore, the conventional drawbacks can be sufficiently solved. In this case, when executing a pattern development, as shown in FIG. 10, a check is first made to see if a pattern to be developed exists in the cache memory or not (step S0 in FIG. 10) before step S1 in FIG. 3 is performed. If YES, the developing process is executed (step S10 in FIG. 10). If NO, a check is made in step S1 in FIG. 3 to see if such a pattern exists in the outputting memory or not. | An outputting apparatus comprises: a discriminating circuit to discriminate whether the same pattern as the pattern to be developed at a predetermined position has already been developed in an outputting memory or not; a copying device to copy the same pattern to the predetermined position when the same pattern which has already been developed exists; a memory to store code information, decoration information, and developing position information of the pattern developed in the outputting memory; a cache memory to store patterns whose use frequencies are high; and a deciding circuit to decide whether the pattern in the outputting memory doesn't overlap another pattern or not. A process to develop a character symbol pattern into the outputting memory can be efficiently executed. | 6 |
BACKGROUND
The field of the present invention is building systems and building methods. In particular, the present invention is directed to a building system and method for use in the manufacture of buildings and other structures capable of withstanding substantial natural forces.
Recently, substantial attention has been directed to the development of systems and methods for constructing buildings (and other structures) which are substantially impervious to attack by extreme forces of nature, for example, hurricanes, earthquakes and the like. Unfortunately, few, if any, systems and methods have been developed which are both economically efficient and capable of providing the structural support necessary to withstand the natural forces present in, for example, a hurricane or earthquake.
SUMMARY OF THE INVENTION
The present invention is directed to an improved building system and method which is both economically efficient and capable of creating a structure which is capable of withstanding substantial natural forces.
In accordance with one form of the present invention, interlocking expanded polystyrene forms (often referred to herein as "PolyBLOC") are used to create an initial shell structure. The expanded polystyrene blocks are coupled to a foundation using, for example, dual "J" tracks and stacked one on top of another to form one or more wall structures. The polystyrene blocks, when coupled together, form a plurality of hollow, interlocking, horizontal and vertical columns therebetween. These columns are adapted to receive and distribute concrete as it is poured into the wall structure. These columns are also adapted to receive and support steel reinforcing bars. Once an initial structural shell has been constructed using the polystyrene blocks, and once any required steel reinforcing bars have been properly positioned therein, concrete is pumped into the top of the wall structure. The pouring process progresses linearly and continuously along the upper surface of the wall structure filling the wall structure to a prescribed level. This process continues in a round-about or overlapping fashion (depending upon the structure being poured) until all of the horizontal and vertical columns within the wall structure have been filled with concrete. It is preferred that all of the concrete disposed within the wall structure cure at the same time to insure that no cold joints (or distinct layers of cured concrete) are formed within the concrete.
By ensuring that no cold joints are formed within any of the horizontal or vertical columns of the concrete pumped into the polystyrene block shell, and by allowing all of the concrete poured within the shell to cure simultaneously, an extremely strong structure is produced.
In one preferred form, the concrete used to fill the horizontal and vertical columns within a wall structure may be 4,000 p.s.i., pee gravel, or "shot mix", having a 9" slump. However, where high strength concrete is required, 6,000-10,000 p.s.i. concrete may be utilized.
Structures constructed using the system and method of the present invention have been tested and are believed to be capable of withstanding 300+ m.p.h. winds. These or similar structures will also soon undergo substantial seismic testing.
It is an object of the present invention to provide an improved building system and method for creating structures capable of withstanding substantial natural forces (for example, hurricanes and earthquakes).
It is also an object of the present invention to provide a building system and method which is economically efficient.
It is also an object of the present invention to provide an improved building system and method which will produce structures which are resistant to insect infestation (i.e. termite infestation).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1(a) is an illustration of a stay-in-place polystyrene form in accordance with the present invention.
FIG. 1(b) is an illustration of an end or corner unit in accordance with the present invention.
FIG. 1(c) illustrates an expanded polystyrene block form in accordance with the present invention and illustrates the dimensions of such a form.
FIG. 1(d) illustrates a cross-section of the form shown in FIG. 1(c).
FIG. 1(e) provides a top view of the form illustrated in FIG. 1(c) .
FIG. 1(f) provides a left-side view of the form illustrated in FIG. 1(c).
FIG. 1(g) provides a bottom view of the form illustrated in FIG. 1(c).
FIG. 1(h) provides an illustration of an end lintel block and a standard lintel block.
FIG. 2 is an illustration of a partial wall formed of stay-in-place forms in accordance with the present invention.
FIG. 3(a) illustrates an exterior structural shell formed of stay-in-place expanded polystyrene forms in accordance with the present invention.
FIG. 3(b) provides an illustration of a typical tie beam, top plate "J" bolt and hurricane strap section of a wall.
FIG. 3(c) illustrates typical rebar spacing and splicing in accordance with the present invention.
FIG. 3(d) provides an illustration of a wall and footer section.
FIG. 3(e) provides an illustration of a wall at a door opening.
FIG. 3(f) provides an illustration of a cross-section of a wall at a window opening.
FIG. 4 shows a cross-section of a wall and window frame in accordance with the present invention.
FIG. 5 shows a cross-section of a wall and window frame in accordance with another preferred form of the present invention.
FIG. 6 provides an illustration of a section of "J" track (often referred to herein as PolyTRAC).
FIG. 7 provides an illustration of a wire support (often referred to herein as PolyCHAIR) for a reinforcing bar.
FIG. 8 provides an illustration of a mechanical fastener (often referred to herein as a PolyCLIP).
DESCRIPTION
The building system (and method) of the present invention is a fully engineered building system which utilizes expanded polystyrene stay-in-place forms and high strength concrete as core elements of a finished housing shell. The various components and the methods of the present invention develop a residential, commercial or industrial building shell which offers very high resistance to damage or failure from hurricane force winds and seismic loading.
Theoretical engineering models indicate a wind resistance loading of 440 m.p.h. for the vertical wall sections, constructed of reinforced concrete utilizing the stay-in-place forms and methods of the present invention. The roofing elements are designed and fabricated from cold rolled formed galvalum steel. This portion of the shell can be designed to resist wind loading in excess of 300 m.p.h. delivering a useful roof finish life of 50 years. The roofing element of the present invention can be fabricated and assembled on a job site or at an assembly site distant from a primary manufacturing facility.
With a properly engineered and executed monolithic slab (or traditional footer) in place the erection of the stay-in-place forms of the present invention may commence. Window, door and column floor pattern and placement layout is transferred to the slab or footer surface in a conventional fashion.
Turning now to the drawings, FIGS l(a) and l(b) illustrate two forms of an expanded polystyrene stay-in-place form which is utilized in accordance with the present invention. FIG. 1(a) illustrates a standard form 10, and FIG. 1(b) illustrates a corner form 12. It is presently preferred that the forms 10 and 12 be 40" in length, 10" in width, and 12" in height (see FIGS. 1(c)-1(h) for further illustrations and dimensions). It is also preferred that each of the forms 10 and 12 hold approximately 1.377 cubic feet of concrete. Expanded polystyrene forms of this type may be obtained from Sola Caribe, Inc., of Fort Lauderdale, Fla.
Turning now also to FIG. 2, to form an external shell of a wall or other structure, the forms 10 and 12 are stacked one on top of another in an interlocking fashion. Thus, as shown in FIG. 2, steel reinforcing bars 14 and 15 may be disposed within the shell of a wall (or other structure) as needed.
The construction process using the system and method of the present invention proceeds as follows. First, a dual "J" track 20 ("PolyTRAC", manufactured by Sola Caribe, Inc. of Fort Lauderdale, Fla.), such as that illustrated in FIG. 6, is attached to the outer edge of the slab (see FIG. 4). PolyTRAC, or dual "J" track 20, is a cold rolled galvalum steel profile that acts as a floor track which receives the first course (or level) of PolyBLOC. The PolyTRAC 20 keeps the stay-in-place forms 10 and 12 of the first course in position during the erection process. In addition, during the placement of concrete the dual "J" track 20 dramatically reduces the potential for "blow out" of the stay-in-place forms 10 and 12 at the bottom of the first course due to the hydrostatic pressure generated by concrete falling from as high as 12 feet.
The dual "J" track 20 also may be placed on the top course of the stay-in-place forms 10 and 12 in a reverse position (an inverted "J"). This creates a mechanical attachment surface for the addition of sheet rock or other interior/exterior surface finishes. Sheet rock may be laid out vertically, instead of in the traditional horizontal pattern, potentially eliminating 33% of the joint finishing required. At the time the "J" track installation is proceeding, a small 1"×5" prepunched galvalum metal clip is installed at 10-foot intervals between the slab and the "J" track and is anchored with the track. For future reference this clip will be described as a "J track clip". The purpose of this clip is for tie down and securing of the stay-in-place form wall prior to placement of concrete.
Turning now to FIG. 3, the erection of the multiple courses of the stay-in-place forms proceeds as follows. The courses are laid from a corner 30 to the center 32 with the less than full stay-in-place forms 16 set in the middle of the course. Corners are formed by the use of an end block 12 and run block 10. At the commencement of a course, a corner end block 12 is placed at the extreme end of the course and a run block 10 is placed perpendicular to the end block at the corner at 90 degrees.
Where the placement of horizontal reinforced steel is required the steel bar is supported by a formed wire shape structure 24 ("PolyCHAIR", illustrated in FIG. 7, and manufactured by Sola Caribe, Inc. of Fort Lauderdale, Fla.), which is inserted into the stay-in-place blocks 10 and 12 transversely to the exterior wall of the blocks 10 and 12, between the longitudinal interlocking track supports the horizontal steel bar.
At appropriate linear dimensions vertical super supporting columns are created by cutting and removing a cross-web of the stay-in-place forms 10 and 12, creating a vertical column approximately 17"×6.25" with vertical reinforced steel.
At the top course of a wall or at the top course of a wide opening (garage door, large front window area, etc.) where additional up or down load bearing support is required, a concrete beam is a developed by installing a beam block (or lintel block) 18 (shown in FIG. 1(h)). This is used in place of an end block 12 or run block 10. The beam block 18 develops a horizontal concrete beam 6.26" in width by 10" in depth by the length of the run. This volume area can accommodate large profile super reinforcing steel to meet design loading requirements.
When it is determined that mechanical fastening from the poured concrete wall structure through the expanded polystyrene stay-in-place forms 10 and 12 is required a PolyCLIP 22 (manufactured by Sola Caribe, Inc. of Fort Lauderdale, Fla.), such as that shown in FIG. 8, is installed during the erection of the PolyBLOC wall in the appropriate pattern for the fastening requirements. The PolyCLIP 22 is a blanked and formed cold rolled galvalum steel profile clip which is designed to snap over the longitudinal profile of the stay-in-place forms 10, 12 and 18. The PolyCLIP 22 protrudes 2" into the interior void of the PolyBLOC 10, 12 and 18 having a 1" punched hole on the interior tab. On the outer surface the PolyCLIP 22 is formed downward on the exterior surface of the stay-inplace forms 10 and 12. An exterior tab allows for screwing, riveting or nailing of exterior finishing systems to the stay-in-place forms 10 and 12. The interior tab of PolyCLIP 22 is cast into the wet concrete and creates an embedded anchor for the load bearing requirements of the exterior finish.
When the stay-in-place form wall has been erected to its full height and the perimeter is complete, a PolyFRAME (manufactured by Sola Caribe, Inc. of Fort Lauderdale, Fla.) door or window framing system can be installed.
Turning now also to FIGS. 4 and 5, the PolyFRAME door or window framing system comprises a polyvinylchloride extrusion, of appropriate strength to resist deformation from the placement of concrete during the form wall filling process. The PolyFRAME extrusion may be cut to fit virtually any size required by the design for a window or door opening. The cut extrusion sections are placed in a welding frame and electronically welded, creating an interior and exterior, slide together, window or door surround frame. The PolyFRAME profile incorporates an exterior and interior ledge for the placement of hurricane shutters. Depending on the anticipated strength of a pending hurricane two shutter surfaces can be mounted in each window. Additionally, there is virtually no maintenance over the life of the PolyFRAME as it cannot crack, chip or peal, virtually eliminating all work for the home or building owner.
Once the PolyFRAME window and door frames are installed and braced, the entire wall is plumbed and trued. An "H" frame profile is placed over the top course of PolyBLOC offering a protective tie down surface over the top of the wall. By attaching a "S" hook to the "J track clip" a tie down line is secured to both sides of the PolyBLOC wall at the "J" track. The tie down line is then pulled down tight, creating a downward force which will prevent the PolyBLOC from upward movement during the concrete placement process. At this time exterior bracing is placed from the top of the PolyBLOC wall to the ground. This brace incorporates a connecting member from the top course of the PolyBLOC wall to a large turn buckle. The turn buckle is anchored to a stack in the ground and the wall is then plumbed vertical via the turn buckle.
With the form wall properly secured and plumbed the placement of concrete may commence. The concrete is best placed by the use of a 2"-3" concrete pump. The concrete design mix for the form wall should be 4,000 p.s.i., pee gravel or "shot mix", 9" slump. The concrete is modified at the job site with the use of Fritz Chemical Slump enhancer. The appropriate amount of additive, based upon concrete volume, is placed in the ready mix truck and site blended for 5-8 minutes. The placement of concrete proceeds in a continuous lift by continual movement of the rolling scaffold form where the crew member directs the placement with a 2" pumping hose while he is moved by one or more additional pump crew members on the slab. Preferably, the forms of the present invention are pumped to full height, in continuous lifts, thus never causing a "cold joint".
Where high strength concrete is required by engineering design the concrete methods of the present invention can develop 6,000-10,000 p.s.i. concrete with ease. High strength concrete, while initially more costly, can prove to be the most cost effective material to use in many design/construction applications, as it develops a virtually fail proof structural construction material. Further, as high strength concrete is far less porous than standard concrete, greater protection is developed for the reinforcing steel disposed therein. The lower porosity does not allow salts and other destructive elements to penetrate into the material. These conditions are easily achieved with the PolyBLOC building system of the present invention.
Upon the completion of the placement of concrete in the form walls, appropriate hurricane anchors, such as those shown in FIG. 3(b), are inserted into the wet concrete at the top course and allowed to remain so as to become mechanically attached in the concrete. These anchors are placed at the correct locations to allow the attachment of roof truss members to be mechanically affixed thereto. This greatly increases the ultimate uplift loading capacity of the structural members of a roof in accordance with the present invention.
Once the form walls have commenced their cure, approximately 12 hours, based upon nominal set time delay, the placement of exterior stucco can commence. PolyCOAT (manufactured by Sola Caribe, Inc. of Fort Lauderdale, Fla.) is an acrylic based bonding agent which, when properly mixed with a cementeous based exterior or interior stucco/plaster system, causes great bonding action to take place with the expanded polystyrene surface of the PolyBLOC (forms 10 and 12). Typical scratch coating surfacing is completed using the PolyCOAT and final finishing may continue upon the cure of the PolyCOAT modified scratch coating.
Interior wall finishing is achieved with conventional wall board (sheet rock). The wall board is mechanically fastened at the top and bottom of the PolyBLOC wall by screwing the wall board to the top and bottom PolyTRAC. The open field of the wall board can be glued to the PolyBLOC wall using PolyNAIL (manufactured by Sola Caribe, Inc. of Fort Lauderdale, Fla.). PolyNAIL is an adhesive, creating a non-removable bonding from virtually any material to the expanded polystyrene surface. PolyNAIL does not cause cavitation of the expanded polystyrene which is very common with most adhesive systems available for wall board.
Upon 24 hours of cure of the concrete placed in the PolyBLOC wall the placement the roof structural members may commence. The roof can then be finished per plan.
While the present invention is susceptible to various modification and alternative forms, specific examples thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that it is not intended the limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claim(s). | An improved system and method for constructing buildings, or other structures, which are capable of withstanding substantial natural forces. Interlocking expanded polystyrene forms are used to create an initial shell structure. The expanded polystyrene blocks are coupled to a foundation using, for example, dual "J" tracks and stacked one on top of another to form one or more wall structures. The polystyrene blocks, when coupled together, form a plurality of hollow, interlocking, horizontal and vertical columns therebetween. These columns are adapted to receive and distribute concrete as it is poured into the wall structure. These columns are also adapted to receive and support steel reinforcing bars. Once an initial structural shell has been constructed using the polystyrene blocks, and once any required steel reinforcing bars have been properly positioned therein, concrete is pumped into the top of the wall structure. The pouring process progresses linearly and continuously along the upper surface of the wall structure filling the wall structure to a prescribed level. This process continues in a round-about or over-lapping fashion (depending upon the structure being poured) until all of the horizontal and vertical columns within the wall structure have been filled with concrete and insures that no cold joints are formed within the concrete. | 4 |
TECHNICAL FIELD OF THE INVENTION
The present invention is directed, in general, to image retrieval systems and, more specifically, to an image retrieval system using color-based segmentation to retrieve region-based images.
BACKGROUND OF THE INVENTION
The advent of digital television (DTV), the increasing popularity of the Internet, and the introduction of consumer multimedia electronics, such as compact disc (CD) and digital video disc (DVD) players, have made tremendous amounts of multimedia information available to consumers. As video and animated graphics content becomes readily available and products for accessing it reach the consumer market, searching, indexing and identifying large volumes of multimedia data becomes even more challenging and important.
The term “visual animated data” herein refers to natural video, as well as to synthetic 2D or 3D worlds, or to a mixture of both video and graphics. Different criteria are used to search and index the content of visual animated data, such as a video clip. Video processing devices operating as image retrieval systems have been developed for searching frames of visual animated data to detect, identify and label objects of a particular shape or color, or to detect text in the frames, such as subtitles, advertisement text, or background image text, such as a street sign or a “HOTEL” sign.
Many of the existing image retrieval systems require a template image in order to search for all the images that resemble the template. For many applications, sub-image matching or object shape-based matching might be more desirable than full-image matching. For instance, a user may wish to retrieve images of red cars from an archive of images, but may not want to retrieve the remaining portion of the original image. Alternatively, a user may have a particular interest in retrieving all images that include a particular shape or a combination of shapes. This type of image retrieval is known as “region-based image retrieval.”
The extraction of image regions in an automatic and robust fashion is an extremely difficult task. Although image segmentation techniques have been studied for more than thirty years, segmentation of color images in real-world scenes is still particularly challenging for computer vision applications. This is primarily due to illumination changes in images, such as shade, highlights, and sharp contrast. For example, nonuniform illumination produces nonuniformity in the values of image pixels in RGB and YUV color spaces in conventional image segmentation techniques.
There is, therefore, a need in the art for improved video processing devices capable of performing region-based image retrieval. In particular, there is a need for improved region-based image retrieval systems capable of performing color-based segmentation that are less sensitive to illumination conditions.
SUMMARY OF THE INVENTION
To address the above-discussed deficiencies of the prior art, it is a primary object of the present invention to provide, for use in an image retrieval system capable of analyzing an image comprising a plurality of pixels in a first color model format, an image processing device capable of detecting and retrieving from the image a selected image portion. The image processing device comprises an image processor capable of converting the plurality of pixels in the image from the first color model format to a (Y,r,θ) color model format, wherein for each pixel in the plurality of pixels, Y is an intensity component indicating a total amount of light, r is a saturation component indicating an amount of white light mixed with a color of the pixel, and θ is a hue component indicating the color of the pixel. The image processor is capable of grouping spatially adjacent ones of the plurality of pixels into a plurality of image regions according to hue components of the adjacent pixels and performing a merging process wherein a first image region and a second image region proximate the first image region are merged into a composite region if a hue difference between the first and second image regions is less than a predetermined hue difference threshold.
According to an exemplary embodiment of the present invention, the image processor is capable of determining a histogram of hue components of the pixels in the image, the histogram indicating a number of pixels of similar hue in the image.
According to one embodiment of the present invention, the image processor is capable of determining a dominant hue in the image using a peak detection algorithm on the histogram.
According to another embodiment of the present invention, the image processor is capable of determining and marking ones of the plurality of image regions having less than a predetermined minimum number of pixels and disregarding the marked image regions during the merging process.
According to still another embodiment of the present invention, the image processor is capable of determining and marking achromatic ones of the plurality of image regions having less than a predetermined minimum number of pixels and disregarding the marked achromatic image regions during the merging process.
According to yet another embodiment of the present invention, the first and second image regions are merged if a number of pixels in the first image region and a number of pixels in the second image region are greater than a predetermined image region size threshold.
According to a further embodiment of the present invention, the image processor is capable of determining a plurality of adjacent regions to the first image region and calculating merit values for the plurality of adjacent regions, wherein a merit value of a first selected adjacent region is equal to a ratio of a common perimeter of the first image region and the first selected adjacent region to a total perimeter of the first selected adjacent region.
According to a still further embodiment of the present invention, the image processor selects the second image region to be merged with the first image region according to a merit value of the second image region.
The foregoing has outlined rather broadly the features and technical advantages of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.
Before undertaking the DETAILED DESCRIPTION, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “processor” or “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, wherein like numbers designate like objects, and in which:
FIG. 1 illustrates an exemplary image retrieval system in accordance with one embodiment of the present invention;
FIG. 2 illustrates an exemplary original image file and a converted image file in the segmentation work space of the image retrieval system in FIG. 1;
FIG. 3 illustrates an exemplary color space for converting image files in accordance with one embodiment of the present invention; and
FIG. 4 is a flow diagram which illustrates the operation of an image retrieval system in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
FIGS. 1 through 4, discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged image retrieval system.
FIG. 1 illustrates exemplary image retrieval system 100 in accordance with one embodiment of the present invention. Image retrieval system 100 comprises image processing system 110 , external databases 180 , monitor 185 , and user devices 190 . Image processing system 110 provides the means for retrieving region-based images from within selected image files.
External databases 180 provides a source for retrieval of a digitized visual image or images as well as other information for use by the system, as required. These databases may be provided through access with a local area network (LAN), wide area network (WAN), internet, and/or other sources such as direct access to data through external devices such as tape, disk, or other storage devices.
Monitor 185 provides means for visual display of the retrieved images. User device(s) 190 represents one or more peripheral devices that may be manipulated by the user of image retrieval system 100 to provide user inputs for the system. Typical peripheral user input devices include a computer mouse, a keyboard, a lightpen, a joystick, a touch-table and associated stylus, or any other device that may selectively be used to enter, to select, and to manipulate data, including all or portions of the retrieved image(s). User device(s) 190 may also include output devices, such as a color printer, which can be utilized to capture a particular retrieved or modified image.
Image processing system 110 comprises image processor 120 , random access memory (RAM) 130 , disk storage 140 , user input/output (I/O) card 150 , video card 160 , I/O interface 170 , and processor bus 175 . RAM 130 further comprises segmentation work space 132 and image retrieval controller 134 . Processor bus 175 transfers data between all of the components of image processing system 110 . Image processor 120 provides over-all control for image processing system 110 and performs the image processing needed to implement image segregation of the present invention, as well as other requirements for image retrieval and editing systems. This includes processing of color images in accordance with the principles of the present invention, processing image editing functions, processing of digitized video images for transfer to monitor 185 or for storage in disk storage 140 , and control of data transfer between the various elements of the image processing system. The requirements and capabilities for image processor 120 are well known in the art and need not be described in greater detail other than as required for the present invention.
RAM 130 provides random access memory for temporary storage of data produced by image processing system 110 , which is not otherwise provided by components within the system. RAM 130 includes memory for segmentation work space 132 , image retrieval controller 134 , as well as other memory required by image processor 120 and associated devices. Segmentation work space 132 represents the portion of RAM 130 in which the initial video image and any modified region-based images are temporarily stored during the color segmentation process. Segmentation work space 132 provides means for defining image region(s) and segmenting image(s), shapes, and areas of the same color from an externally or internally supplied original visual image without impacting the original data so that the original data and image can be recovered, as required. Image retrieval controller 134 represents a portion of RAM 130 that is dedicated to storage of an application program executed by image processor 120 to perform region-based image retrieval using color-based segmentation of the present invention. Image retrieval controller 134 may execute well-known editing techniques, such as smoothing or boundary detection between images, as well as the novel techniques for image separation associated with the present invention. Image retrieval controller 134 may also be embodied as a program on a CD-ROM, computer diskette, or other storage media that may be loaded into a removable disk port in disk storage 140 or elsewhere, such as in external databases 180 .
Disk storage 140 comprises one or more disk systems, including a removable disk, for “permanent” storage of programs and other data, including required visual data and the program instructions of image retrieval controller 134 . Depending upon system requirements, disk storage 140 may be configured to interface with one or more bidirectional buses for the transfer of visual data to and from external databases 180 , as well as the rest of the system. Depending upon specific applications and the capability of image processor 120 , disk storage 140 can be configured to provide capability for storage of a large number of color images.
User I/O card 150 provides means for interfacing user device(s) 190 to the rest of image processing system 100 . User I/O card 150 converts data received from user devices 190 to the format of interface bus 175 for transfer to image processor 120 or to RAM 130 for subsequent access by image processor 120 . User I/O card 150 also transfers data to user output devices such as printers. Video card 160 provides the interface between monitor 185 and the rest of image processing system 110 through data bus 175 .
I/O interface 170 provides an interface between external databases 180 and the rest of image processing system 100 through bus 175 . As previously discussed, external databases 180 has at least one bidirectional bus for interfacing with I/O interface 170 . Internal to image processing system 110 , I/O interface 170 transfers data received from external databases 180 to disk storage 140 for more permanent storage, to image processor 120 , and to RAM 130 to provide temporary storage for segmentation and monitor display purposes.
FIG. 2 illustrates exemplary original image file 210 and converted image file 220 in segmentation work space 132 of the image retrieval system in FIG. 1 . Original image file 210 provides storage for each pixel (labeled 1 though n) associated with the original image received from external databases 180 in, for example, RGB format. The storage space for each pixel is sized for the maximum number of color value bits required for is the particular implementation, as well as any other bits of information typically available for a color image system. Conventional RGB-based color image systems cover a range from 8 bits/pixel to 24 bits/pixel, though larger systems can be accommodated with appropriate memory increases. The converted image file 220 provides n storage locations for the pixels in the (Yrθ) format of the present invention.
FIG. 3 illustrates exemplary color space 300 for use in converting image files in (RGB) format or (YUV) format to (Yrθ) format in accordance with one embodiment of the present invention. Color space 300 represents color in terms of intensity (Y), which indicates the total amount of light, saturation (r), which indicates the amount of white light mixed with color, and hue (θ), which represents the type of color which is present. Image processor 120 converts pixels from, for example, (RGB) format or (YUV) format in the original image file to (Yrθ) format using one or more of the following formulae:
V=R−Y
U=B−Y
θ=arctan ( V/U )
r=(U 2 +V 2 ) ½
Y=Y
In a similar manner, image processor 120 may convert pixels in other color space formats to (Yrθ) format.
FIG. 4 depicts flow diagram 400 which illustrates the operation of image retrieval system 100 in accordance with one aspect of the present invention. Initially, the stored RGB formatted image file received from external databases 180 is converted to (Yrθ) format using the conversion equations and is stored in converted image file 132 (process step 405 ). Next, image processor 120 uses the n pixels in (Yrθ) format to develop a one-dimensional (1-D) histogram of hue (θ) for each converted pixel (process step 410 ). The histogram is restricted to pixels for which r>5 and Y>40. This is because at small values of r, θ is unstable and, when Y is low, θ is meaningless (indicates a low level of light which causes colors to merge toward black or achromatic).
The dominant color or colors, d(θ), is/are then determined from the histogram using a peak detection algorithm (process step 415 ) that identifies the color or colors having the highest proportions of pixels. The histogram is examined and pixels are identified as having color (chromatic) or no color (achromatic). The dominant color(s) and chromatic or achromatic information is stored in RAM 132 segmentation work space 12 for later use.
Next, image processor 120 examines the converted image pixels and groups them according to color and location. Pixels with the same color label (Yrθ description) are examined to determine their proximity to others within the color group. Spatially adjacent pixels with the same color label are grouped together as image regions (process step 420 ).
Chromatic image regions with less than a predefined minimum threshold number of pixels (e.g., 10 pixels) and achromatic regions with less than a predefined minimum threshold number of pixels (e.g., 20 pixels) are marked off for post-processing. Achromatic regions with more than a predefined maximum threshold number of pixels (e.g., 20 pixels) are also marked off to prevent them from being merged with other regions. In addition, the remaining chromatic image regions are grouped by size and chromacity as a basis for initial merging. One embodiment of the present invention identifies comparatively large image regions with greater than, for example, 200 pixels as potential merger candidates (process step 425 ).
Next, image processor 120 examines the comparatively large image regions to determine color, θ, similarity and the amount of mutual border space (shared perimeter) with other suitable regions. One embodiment of the present invention uses a merit function which determines the percentage of shared border or perimeter space compared to the sum of the individual region perimeters:
merit func.=shared perimeter/(perimeter 1 +perimeter 2 )
Using this merit function, two neighboring regions are selected as initial candidates for image merging (process step 430 ).
The colors of the selected image regions are examined to determine the degree of similarity. If the difference between colors is less than a pre-defined threshold difference (for example 10°), the regions are merged, the combined region replaces the merged regions in the large region segmentation work space, and the process continues. If the color difference between neighboring regions is greater than the threshold, the regions are not merged, and the process continues until no more mergers are possible (process step 435 ).
Once all large regions are merged with those of like or similar color space, image processor 120 examines the smaller regions previously identified for post-processing to determine shared perimeters and similar color indicator with the merged regions. The smaller regions are then merged with larger regions with shared perimeters and similar θ and the result is stored in the segmentation work space (process step 440 ). At this point, the merged image regions are stored as a segmented image file which is then available for use by image processor 120 via control by user manipulation of user devices. The segmented image files may then be stored in disk storage 140 for later retrieval and use.
Although the present invention has been described in detail, those skilled in the art should understand that they can make various changes, substitutions and alterations herein without departing from the spirit and scope of the invention in its broadest form. | There is disclosed an image retrieval system for analyzing an image in a first color model format and detecting and retrieving from the image a selected image portion. The image retrieval system comprises an image processor for converting pixels in the image from the first color model format to a (Yrθ) color model format, where Y is an intensity component indicating a total amount of light, r is a saturation component indicating an amount of white light mixed with a color of each pixel, and θ is a hue component indicating the color of each pixel. The image processor groups spatially adjacent pixels into image regions according to hue components of the adjacent pixels and performs a merging process wherein a first image region and an adjacent second image region are merged into a composite region if a hue difference between the first and second image regions is less than a predetermined hue difference threshold. The process is repeated to continually merge regions of similar hue until no further merges can be performed. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This patent application is a U.S. National Stage under 35 U.S.C. §371 of International Application No. PCT/CN2011/084039, filed on Dec. 15, 2011, entitled METHOD AND SYSTEM FOR REPORTING TERMINAL MEASUREMENT AND INTER-OPERATING BETWEEN SYSTEMS, designating the United States, and claiming priority from Chinese Patent Application No. 201010593509.3, filed with the Chinese Patent Office on Dec. 17, 2010 and entitled “Method and system for reporting terminal measurement and inter-operating between systems”, which is herein incorporated by reference in its entirety.
This application claims priority from Chinese Patent Application No. 201010593509.3, filed with the Chinese Patent Office on Dec. 17, 2010 and entitled “Method and system for reporting terminal measurement and inter-operating between systems”, which is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to the field of wireless communication technologies and particularly to a method and device for reporting terminal measurement and inter-system interoperation.
BACKGROUND OF THE INVENTION
In order to support a higher data transmission rate and to provide users with high-quality service, multi-carrier technologies are supported at present in both a Universal Mobile Telecommunication System (UMTS) and a Long Term Evolution-Advance (LTE-A) system, that is, resources of a plurality of carriers are aggregated to obtain a lager bandwidth and to serve a terminal together.
1) Multi-Carrier/Multi-Cell Technologies in UMTS
In order to improve a user peak rate and cell data throughput, in the UMTS system, multi-cell technologies are introduced for a Frequency Division Duplexing (FDD) mode, while multi-carrier technologies is introduced for a Time Division Duplexing (TDD) mode. The multi-carrier/multi-cell technologies are supported at present for both a High Speed Downlink Packet Access (HSDPA) and a High Speed Uplink Packet Access (HSUPA).
For the FDD mode, there is only one carrier in a cell, and the multi-cell technologies refer to aggregation of a plurality of consecutive or inconsecutive carriers under a same NodeB together to serve a UE concurrently to thereby provide a desired rate. The multi-cell technologies involve dual cells in the downlink, four cells in the downlink, dual cells in the uplink, etc., each cell of which is a backward-compatible cell that can independently operate, and when they serve a terminal concurrently, there is one and only one primary cell, and the others are all secondary cells.
For the TDD mode, there are multiple carriers in a TDD cell, and the multi-carrier technologies refer to aggregation of multiple carriers of the same TDD cell for communication by a UE. Multiple carriers in the TDD mode include three carriers in the downlink, six carriers in the downlink, and three carriers in the uplink, etc., and all of these carriers that can operate concurrently belong to the same TDD cell; and for the UE, only a primary cell is a backward-compatible cell that can independently operate, and the other secondary cells can be regarded as resources for use only under the multi-carrier technologies.
2) Carrier Aggregation Technology in LTE-A
In an LTE system, there is only one carrier with the maximum bandwidth of 20 MHz in a cell, as illustrated in FIG. 1 .
In the LTE-A system, peak rates of the system have been greatly improved over the LTE system, and are required to reach 1 Gbps in the downlink and 500 Mbps in the uplink. The required peak rates can not be reached if only one carrier with the maximum bandwidth of 20 MHz is used. Thus, the LTE-A system has to extend the bandwidth available to the terminal, and to this end, a Carrier Aggregation (CA) technology has been introduced, that is, a plurality of consecutive or inconsecutive carriers under a same evolved NodeB, eNB, are aggregated together to serve the UE concurrently to thereby provide a desired rate. These carriers aggregated together are also referred to Component Carriers (CCs). Each cell can be a component carrier, and cells (component carriers) under different eNBs can not be aggregated.
In order to ensure that the UE in the LTE system can operate over each aggregated carrier, the bandwidth of each carrier shall not exceed 20 MHz at most. The CA technology of the LTE-A system is as illustrated in FIG. 2 , and under the evolved NodeB in the LTE-A system illustrated in FIG. 2 , there are four carriers that can be aggregated, and the evolved NodeB can transmit data with the UE concurrently over the four carriers to thereby improve system throughout.
An inter-system interoperation technology, that is, Inter-Radio Access Technology (Inter-RAT), refers to a technology of interoperation between different systems, e.g., a handover technology between the UMTS system and the LTE system (Packet Switched Handover (PS HO)) and a redirection technology, and the use of these technologies can enable cooperative operation between different heterogeneous networks to better serve a multimode terminal. For a multimode terminal supporting both the UMTS system and the LTE system, a single-carrier handover between them is supported in existing protocols in order to ensure service continuity thereof and will be detailed below.
As illustrated in FIG. 3 , it is an architecture of a UMTS network, which includes two parts: a Core Network (CN) and a UMTS Terrestrial Radio Access Network (UTRAN), wherein access network nodes in a PS domain includes a NodeB and a Radio Network Controller (RNC) which is connected with a Serving GPRS Support Node (SGSN) and a Mobile Switching Center (MSC)/Visitor Location Register (VLR). As illustrated in FIG. 4 , it is an architecture of an LTE (also referred to as E-UTRAN) network, wherein access network nodes include an evolved NodeB, eNB, connected with a Mobility Management Entity (MME)/Serving Gateway (S-GW).
As illustrated in FIG. 5 , it is an Inter-RAT network architecture between UMTS and LTE. The existing UMTS device, SGSN, has to be updated to support an interface S4 and thus can be referred to as an S4 SGSN. In this network architecture, all the user plane data passes through two core network nodes which are a Packet Data Network Gateway (PDN GW) and the Serving GW. The SGSN and the MME transmit control plane signaling via an interface S3.
When a terminal resides in the UMTS network, the terminal receives user plane data through the PDN GW, the Serving GW, the SGSN, the RNC and the NodeB via interfaces S5, S4, Iu and Iub; and when the terminal switches to the LTE network, the terminal receives user plane data through the PDN GW, the Serving GW and the eNB via interfaces S5 and S1-U.
If the terminal is intended to forward data, then there are two schemes, in one of which a direct data forward tunnel is established between the RNC and the eNB through the SGSN and the MME; and in the other of which an indirect data forward tunnel is established between the RNC and the eNB, and the data of the terminal is forwarded to the eNB through the RNC, the SGSN and the Serving GW, or a direct tunnel is established by the SGSN between the RNC and the Serving GW, and the data of the terminal is forwarded to the eNB through the RNC and the Serving GW.
The terminal may switch between different RATs for the reason of movement or channel quality. In order to assist the network to perform a more reasonable handover decision, the UE will measure and report channel quality of another RAT depending on network configuration. There are different measurement parameter configurations and separate measurement procedures for inter-RAT measurement and inter-system measurement, where a measurement gap is typically used. For example, when the E-UTRAN system measures the UTRAN system, an event B1 or an event B2 can be configured and a measurement gap can be configured depending on the capability of the UE. Specific contents of the event B1 and the event B2 are as follows:
Event B1: channel quality of an adjacent cell of a disparate system is above a threshold; and
Event B2: channel quality of a serving cell is below a first threshold, and channel quality of an adjacent cell of a disparate system is above a second threshold.
When the UTRAN system measures the E-UTRAN system, events 3a, 3b, 3c and 3d can be configured particularly as follows:
Event 3a: channel quality of a serving cell is below a first threshold, and channel quality of an adjacent cell of a disparate system is above a second threshold;
Event 3b: channel quality of an adjacent cell of a disparate system is below a threshold;
Event 3c: channel quality of an adjacent cell of a disparate system is above a threshold; and
Event 3d: the strongest cell in an adjacent cell of a disparate system is changed.
Based upon the foregoing network architecture and Inter-RAT measurement mechanism, a simplified flow chart of switching by a terminal from UMTS to LTE at the Radio Access Network (RAN) side is as illustrated in FIG. 6 and generally includes the following steps:
A source RNC sends a measurement configuration message to the terminal; the terminal measures according to the measurement configuration message and reports a measurement result to the source RNC; the source RNC makes a handover decision in view of the reported measurement result; the source RNC sends a handover request to a target eNB through the core network when deciding to switch to LTE; the target eNB sends a handover request acknowledgement to the source RNC through the core network according to the handover request; the source RNC sends a handover command to the terminal; the terminal accesses the target eNB upon reception of the handover command; and the terminal sends a handover completion message after successfully accessing the target eNB.
Particularly, all of the measurement configuration message, the measurement report message, the handover command and the handover completion message are signaling of the access network side. Both the handover request transmitted from the source RNC to the target eNB and the handover request acknowledgement transmitted from the target eNB to the source RNC are containers in interface messages in conformity with a message encapsulation format of the core network and transmitted through the core network. The handover request acknowledgement message contains an RRC container with contents thereof being the handover command, and the source RNC transmits this message to the terminal via a null interface.
Based upon the foregoing network architecture and Inter-RAT measurement mechanism, a simplified flow chart of switching from the LTE system to UMTS at the RAN side is as illustrated in FIG. 7 and generally includes the following steps:
A source eNB sends a measurement configuration message to a terminal; the terminal measures according to the measurement configuration message and reports a measurement result to the source eNB; the source eNB makes a handover decision in view of the reported measurement result; the source eNB sends a handover request to a target RNC through the core network when deciding to switch to LTE; the target RNC sends a handover request acknowledgement to the source eNB through the core network according to the handover request; the source eNB sends a handover command to the terminal; the terminal accesses the target RNC upon reception of the handover command; and the terminal sends a handover completion message after successfully accessing the target RNC.
Particularly, all of the measurement configuration message, the measurement report message, the handover command and the handover completion message are signaling of the access network side. Both the handover request transmitted from the source eNB to the target RNC and the handover request acknowledgement transmitted from the target RNC to the source eNB are containers in interface messages in conformity with a message encapsulation format of the core network and transmitted through the core network. The handover request acknowledgement message contains an RRC container with contents thereof being the handover command, and the source eNB transmits this message to the terminal via a null interface.
No matter whether the handover is from UTMS to LTE or from LTE to UMTS, the measurement configuration message sent from the source access node includes measurement configuration contents, e.g., a measurement object, configured events, a measurement result reporting scheme and the like. The terminal measures according to the measurement configuration contents and reports the measurement result in the configured measurement reporting scheme.
Taking the handover from UTMS to LTE as an example, based upon existing protocols, Inter-RAT measurement in the measurement configuration message sent from the source RNC includes the measurement configuration contents. E-UTRAN Measured Results in the measurement report message reported by the terminal include the measurement result, and E-UTRAN Event Results in the measurement report message include an event result.
Contents of an Information Element (IE) of the E-UTRAN Measured Results particularly include: a carrier frequency of E-UTRAN, and an identifier and a measurement result of a cell satisfying a report condition at the frequency. The measurement result is typically represented by Reference Signal Receiving Power (RSRP) and Reference Signal Received Quality (RSRQ).
Contents of an Information Element (IE) of the E-UTRAN Event Results particularly include: an Inter-RAT measurement event ID, a carrier frequency of E-UTRAN, and an identifier of a cell satisfying a report condition at the frequency.
In the Inter-RAT measurement mechanism in the prior art, the measurement object configured for measurement is a single frequency, that is, only one frequency or a cell at the single frequency is configured, so only an Inter-RAT single-carrier handover but no multi-carrier handover is supported. At present, the multi-carrier technologies have been introduced to both the UMTS and LTE systems to improve the data transmission rate of the user, but when the user using the multi-carrier technologies switches between these two systems, he has to firstly fall back to the single-carrier state to perform a handover of the PS domain and can enter the multi-carrier state again only after finishing the handover. This will undoubtedly lower the data transmission rate of the user and degrade user experience. Moreover, when the terminal switches from another system supporting high-speed data transmission to UMTS or LTE, the multi-carrier handover to these two systems is not supported, thus also lowering the data transmission rate of the user and degrading user experience.
SUMMARY OF THE INVENTION
Embodiments of the invention provide a method and device for reporting terminal measurement and inter-system interoperation, to assist the network to perform a multi-carrier handover between systems to thereby shorten the report delay, improve the data transmission rate when the terminal performs the handover of the PS domain between different systems, and enhance the user experience.
The invention provides a method for reporting terminal measurement, which includes:
receiving measurement configuration information sent from an access device of a source system;
measuring cells on at least two frequencies in a target system according to the measurement configuration information; and
reporting measurement results obtained by measuring the cells on the at least two frequencies in the target system to the access device of the source system when a measurement report is triggered according to the measurement configuration information, so that the access device of the source system determines a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results.
The invention provides a method for inter-system interoperation, which includes:
configuring, by an access device of a source system, a terminal with measurement configuration information when determining that the terminal is to switch to a target system, wherein the measurement configuration information comprises at least two frequencies/cells on at least two frequencies of the target system and a measurement result reporting scheme;
sending, by the access device of the source system, the measurement configuration information to the terminal, and receiving measurement results reported by the terminal; and
determining, by the access device of the source system, a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results, and instructing the terminal to switch to the primary cell and the secondary cell of the target system.
The invention provides a user equipment, which includes:
a measurement configuration receiving unit configured to receive measurement configuration information sent from an access device of a source system;
a measuring unit configured to measure cells on at least two frequencies in a target system according to the measurement configuration information; and
a measurement reporting unit configured to report measurement results obtained by measuring the cells on the at least two frequencies in the target system to the access device of the source system when a measurement report is triggered according to the measurement configuration information, so that the access device of the source system determines a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results.
The invention further provides a network-side access device, which includes:
a measurement configuring unit configured to configure a terminal with measurement configuration information when determining that the terminal is to switch from a current system to a target system, wherein the measurement configuration information comprises at least two frequencies/cells on at least two frequencies of the target system and a measurement result reporting scheme;
an information receiving unit configured to send the measurement configuration information to the terminal and to receive measurement results reported by the terminal; and
a handover assisting unit configured to determine a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results and to instruct the terminal to switch to the primary cell and the secondary cell of the target system.
With the method and device for reporting terminal measurement and inter-system interoperation according to the invention, advantageous effects are as follows: they can assist the network to perform a multi-carrier handover between systems to thereby shorten the report delay, improve the data transmission rate when the terminal performs the handover of the PS domain between different systems, and enhance the user experience.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a carrier distribution in a cell of an LTE system;
FIG. 2 is a schematic diagram of a carrier distribution when using carrier aggregation in an LTE-A system;
FIG. 3 is a network architectural diagram of a UMTS system;
FIG. 4 is a network architectural diagram of the LTE system;
FIG. 5 is a network architectural diagram of interoperation between UMTS and LTE;
FIG. 6 is a flow chart of a handover from UMTS to LTE at the RAN side;
FIG. 7 is a flow chart of a handover from LTE to UMTS at the RAN side;
FIG. 8 is a flow chart of a method for reporting terminal measurement according to an embodiment of the invention;
FIG. 9 is a flow chart of a method for inter-system interoperation according to an embodiment of the invention;
FIG. 10 is a structural diagram of a user equipment according to an embodiment of the invention; and
FIG. 11 is a structural diagram of a network-side access device according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
The method and device for reporting terminal measurement and inter-system interoperation according to the invention will be described below in further details in connection with the drawings and embodiments thereof.
The invention proposes a terminal measurement reporting method for inter-system interoperation to assist the network to perform a multi-carrier handover between systems to thereby shorten the report delay, improve the data transmission rate when the terminal performs the handover of the PS domain between different systems, and enhance the user experience. As illustrated in FIG. 8 , the method includes:
Step S 801 , receiving measurement configuration information sent from an access device of a source system, where the measurement configuration information indicates the terminal how to measure information of a cell in a target system and how to report a measurement result.
Step S 802 , measuring cells on at least two frequencies in the target system according to the received measurement configuration information; and in the method according to the invention, information of cells on at least two frequencies is measured instead of measuring and reporting a cell on a single frequency.
Step S 803 , reporting measurement results obtained by measuring the cells on the at least two frequencies in the target system to the access device of the source system when a measurement report is triggered according to the measurement configuration information, so that the access device of the source system determines a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results.
In the method for reporting terminal measurement according to the invention, the terminal measures cells on a plurality of frequencies and reports measurement results according to configuration of the network side, so the network-side device can obtain measurement information of the plurality of frequencies, and the target system is a system in which a plurality of cells can be aggregated to serve the UE concurrently, and preferably, the foregoing target system is an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) system and of course can alternatively be another system in which a plurality of cells can be aggregated to serve the UE concurrently, while the source system is a system where the User Equipment (UE) currently resides, which can be a UMTS Terrestrial Radio Access Network (UTRAN) system, a GSM EDGE Radio Access Network (GERAN) system, a Wireless Local Area Network (WLAN) system, a Worldwide Interoperability for Microwave Access (WiMAX) system or a Code Division Multi-Access (CDMA) 2000 system. Thus, with the method according to the invention, before a multi-carrier handover (PS HO) to E-UTRAN from another system is performed, the terminal is configured to measure and report a plurality of frequencies of an E-UTRAN cell, so it is possible to assist the network to perform a multi-carrier handover between systems to thereby shorten the report delay, improve the data transmission rate when the terminal performs the handover of the PS domain between different systems, and enhance the user experience.
Preferably, the method for reporting terminal measurement according to the embodiment further includes:
Step S 804 , receiving a handover command sent from the access device of the source system for a handover to the primary cell and the secondary cell of the target system; and
Step S 805 , accessing an access device of the target system according to the handover command to accomplish the handover to the primary cell and the secondary cell of the target system to thereby accomplish the multi-carrier handover to the multi-carrier system.
The invention provides a method for inter-system interoperation, as illustrated in FIG. 9 , which includes:
Step S 901 , configuring, by an access device of a source system, a terminal with measurement configuration information when determining that the terminal is to switch to a target system, wherein the measurement configuration information comprises at least two frequencies/cells on at least two frequencies of the target system and a measurement result reporting scheme;
In order to enable the terminal to measure cells on a plurality of frequencies, the access device of the source system shall configure the plurality of frequencies or configure the cells on the plurality of frequencies, and furthermore, shall further configure a result reporting scheme, so that the terminal reports measurement information of the cells on the plurality of frequencies.
Step S 902 , sending, by the access device of the source system, the measurement configuration information to the terminal, and receiving measurement results reported by the terminal;
As described above, the terminal measures the cells on the at least two frequencies in the target system according to the received measurement configuration information, and reports the measurement results obtained by measuring the cells on the plurality of frequencies in the target system to the access device of the source system according to the configured measurement result reporting scheme when determining that a measurement report is triggered.
Step S 903 , determining, by the access device of the source system, a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results, and instructing the terminal to switch to the primary cell and the secondary cell of the target system.
Preferably, the foregoing target system is an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) system and of course can alternatively be another system in which a plurality of cells can be aggregated to serve the UE concurrently, while the source system is a system where the User Equipment (UE) currently resides, which can be a UMTS Terrestrial Radio Access Network (UTRAN) system, a GSM EDGE Radio Access Network (GERAN) system, a Wireless Local Area Network (WLAN) system, a Worldwide Interoperability for Microwave Access (WiMAX) system or a Code Division Multi-Access (CDMA) 2000 system. Thus, with the method according to the invention, the network-side access device can accomplish a multi-carrier handover of the UE by use of the measurement results reported by the terminal.
Preferably, instructing the terminal to switch to the primary cell and the secondary cell of the target system in the step S 903 specifically includes: sending, the access device of the source system, a handover request to an access device of the target system for a handover to the primary cell and the secondary cell of the target system; and sending, the access device of the source system, a handover command to the terminal upon reception of a handover request acknowledgement returned from the access device of the target system, to instruct the terminal to switch to the primary cell and the secondary cell of the target system. Preferably, the above handover request includes the primary cell and a list of secondary cells of the target system, and preferably, can further include measurement results of the primary cell and the secondary cell.
Preferred implementations of the invention will be given below by taking an E-UTRAN system as the target system.
In a first implementation according to the invention, the embodiment of the invention adds an additional measurement report indicator in the measurement configuration information in the basis of the existing protocols, to instruct the terminal to further report a measurement result of a cell on at least one other frequency in addition to a measurement result of a cell on a frequency which triggers a measurement report. Particularly, the additional measurement report indicator can be set for a measurement event or can alternatively be set for a measurement object, where if the indicator is set for a measurement event, then the measurement event will trigger a report together with an additional report of the measurement result of the cell on the at least one other frequency; and if the indicator is set for a measurement object, e.g., a frequency, then a cell at the frequency will trigger a measurement report together with an additional report of the measurement result of the cell on the at least one other frequency.
In the embodiment of the invention, a plurality of frequencies/cells on a plurality of frequencies are configured in the measurement configuration information, but in a practical measurement process, measurements at respective frequencies will be performed separately, and when measurement at a specific frequency satisfies a report condition, for example, a measurement event configured at one of the frequencies satisfies the report condition, then in the prior art, if the measurement report is set for the frequency, then measurement information of a cell on any other frequency will not be reported. In this embodiment, the additional measurement report indicator is added so that the terminal reports measurement reports of a cell on one of the frequencies which triggers the measurement report and a cell on at least one other frequency to the access device of the source system when determining that the cell on one of the frequencies triggers the measurement report and that there is an additional measurement report indicator in the measurement configuration information.
Preferably, the terminal reports measurement reports of cells with the strongest channel quality on each of currently measured frequencies to the access device of the source system when determining that a cell on one of the frequencies triggers a measurement report and that there is an additional measurement report indicator in the measurement configuration information.
In this embodiment, E-UTRAN Additional Measurement Results are added in the measurement report message reported by the terminal, to thereby include the measurement result of the cell on the at least one other frequency except the measurement result of the cell on the frequency which triggers the measurement report.
In this embodiment, the measurement results obtained by the terminal through measuring the cells on the at least two frequencies in the target system include cell identifiers and/or cell channel quality, where the cell channel quality is typically represented by Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ). The cell channel quality is an instantaneous value or a statistic value obtained by measuring over a preset length of period of time and filtering.
Preferably, the number of frequencies to be reported can be further defined, and in this embodiment, the measurement configuration information further includes the number of frequencies required to be reported, A, and the terminal reports measurement results of cells on A frequencies to the access device of the source system, where A≧2; or the number of cells to be reported per frequency can be further defined, the measurement configuration information further includes the number of cells required to be reported, B, and the terminal reports measurement results of B cells on each of the at least two frequencies to the access device of the source system, where B≧1; or both of the two numbers can be defined, the measurement configuration information further includes the number of frequencies required to be reported, A, and the number of cells required to be reported, B, and the terminal reports measurement results of B cells on each of A frequencies to the access device of the source system.
Preferably, a channel quality threshold of a cell to be reported can be further defined, that is, there is no report if channel quality of a cell is not above the channel quality threshold. In this embodiment, the measurement configuration information further includes the channel quality threshold, and channel quality of each of the cells on the at least two frequencies reported by the terminal is above the channel quality threshold.
In a second implementation according to the invention, one of the frequencies is configured with additional measurement in the measurement configuration information, where the configuration of additional measurement refers to that when a specific frequency is configured for measurement, some other additional measurement frequencies is configured additionally, and when a cell on the frequency configured with the additional measurement triggers a measurement report, cells, of which measurement results are obtained, on the additional measurement frequencies are also reported. Thus, the terminal reports measurement reports of cells with the strongest channel quality on each of additional measurement frequencies related to one of the frequencies which triggers a measurement report to the access device of the source system when determining that the one of the frequencies is configured with additional measurement and a cell on the frequency triggers a measurement report.
Two particular embodiments will be given below.
First Embodiment: In the UTRAN System, an Additional Measurement Report is Performed for E-UTRAN
A dual-mode terminal supporting both U-TRAN and E-UTRAN systems currently operates in UTRAN. An RNC of UTRAN configures the terminal with measurement on E-UTRAN, including a plurality of E-UTRAN frequencies required to be measured, and enables an additional measurement report, that is, measurement configuration information includes an additional measurement report indicator. Assumed E-UTRAN frequencies configured currently for the terminal and required to be measured are f1, f2 and f3, and an additional measurement report is initiated when an event triggered at f1 is reported. As the UE moves, a measurement event configured at f1 satisfies a report condition, and then an additional measurement report is triggered, where reported contents include E-UTRAN cells on f1 satisfying the condition (e.g., a cell 1 and a cell 2) and measurement results of channel quality thereof (RSRP and RSRQ). Since an additional multi-carrier (multi-cell) measurement report is configured, a currently reported measurement report message further includes the strongest E-UTRAN cells on f2 and f3 of which measurement results are obtained (e.g., a cell 3 on f2 and a cell 4 on f3), where “strongest” refers to that the value of RSRP or RSRQ is largest, and also can further include measurement results of these strongest cells (the cell 3 and the cell 4 reported).
Thus, in an Inter-RAT measurement report, in addition to a cell(s) which triggers a measurement report currently, a cell(s) on another frequency (frequencies) is further included, to thereby shorten the report delay and assist the network to make an Inter-RAT multi-carrier handover decision.
Second Embodiment: Multi-Carrier Handover (PS HO) from UTRAN to E-UTRAN
A dual-mode terminal supporting both U-TRAN and E-UTRAN systems currently operates in UTRAN. Assumed the terminal is in the TDD mode and operates in a 6 downlink-carrier state (multi-carrier technology), or the terminal is in the FDD mode and operates in a 4 downlink-cell state (multi-cell technology). An RNC of UTRAN configures the terminal with measurement on E-UTRAN, including a plurality of E-UTRAN frequencies required to be measured, and enables an additional measurement report. If the terminal moves at this time to thereby trigger an Inter-RAT measurement report and also additional multi-carrier (multi-cell) measurement results are included, and thereafter the network decides that the terminal need switch to E-UTRAN, then a source RNC sends a handover request message to a target eNB, where the message carries a target primary cell and a list of target secondary cells to which a handover is requested and also carries measurement results (RSRP and/or RSRQ) of the target secondary cells. Such information is reported as measured by the terminal (including an additional measurement report) and can be put in an interface message or can alternatively be put in an RRC container. For example, the target primary cell is carried in the interface message, and the list of target secondary cells and measurement results thereof are put in the RRC container. If the target eNB agrees to accept the terminal over multiple carriers upon reception of the handover request message from the source RNC, then the target eNB returns a handover request acknowledgement message to the source RNC, where the message carries a handover command including information of multiple cells (one primary cell and one or more secondary cells) to be accessed by the terminal at the target eNB. The source RNC transmits the contents of the handover command to the terminal via a null interface. The terminal initiates a multi-carrier handover from UTRAN to E-UTRAN upon reception of the handover command.
Thus the terminal can accomplish a multi-carrier handover from UTRAN to E-UTRAN to thereby improve the data transmission rate when performing the handover of the PS domain between different systems and enhance the user experience.
The invention further provides a User Equipment (UE) as illustrated in FIG. 10 , which includes: a measurement configuration receiving unit 101 configured to receive measurement configuration information sent from an access device of a source system; a measuring unit 102 configured to measure cells on at least two frequencies in a target system according to the measurement configuration information; and a measurement reporting unit 103 configured to report measurement results obtained by measuring the cells on the at least two frequencies in the target system to the access device of the source system when a measurement report is triggered according to the measurement configuration information, so that the access device of the source system determines a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results.
Preferably, the measurement reporting unit 103 is specifically configured to report measurement reports of a cell on one of the frequencies which triggers a measurement report and a cell on at least one other frequency to the access device of the source system when determining that the cell on one of the frequencies triggers the measurement report and that there is an additional measurement report indicator in the measurement configuration information.
Preferably, the measurement reporting unit 103 is specifically configured to determine to trigger a measurement report when a measurement event configured at one of the frequencies satisfies a report condition.
The measurement configuration information further comprises the number of frequencies required to be reported, A, and the measurement reporting unit 103 is specifically configured to report measurement results of cells on A frequencies to the access device of the source system, where A≧2; or
The measurement configuration information further comprises the number of cells required to be reported, B, and the measurement reporting unit 103 is specifically configured to report measurement results of B cells on each of the at least two frequencies to the access device of the source system, where B≧1; or
The measurement configuration information further comprises the number of frequencies required to be reported, A, and the number of cells required to be reported, B, and the measurement reporting unit 103 is specifically configured to report measurement results of B cells on each of A frequencies to the access device of the source system.
Preferably, the measurement configuration information further comprises a channel quality threshold, and channel quality of each of the cells on the at least two frequencies reported by the measurement reporting unit 103 is above the channel quality threshold.
Preferably, the measurement reporting unit 103 is specifically configured to report measurement reports of cells with the strongest channel quality on each of currently measured frequencies to the access device of the source system when determining that a cell on one of the frequencies triggers a measurement report and that there is an additional measurement report indicator in the measurement configuration information.
Preferably, the measurement reporting unit 103 is specifically configured to report measurement reports of cells with the strongest channel quality on each of additional measurement frequencies related to one of the frequencies which triggers a measurement report to the access device of the source system when determining that the one of the frequencies is configured with additional measurement and a cell on the frequency triggers a measurement report.
Preferably, the measurement results obtained by the measuring unit through measuring the cells on the at least two frequencies in the target system comprise cell identifiers and/or cell channel quality; and the cell channel quality is an instantaneous value or a statistic value measured over a preset length of period of time.
Preferably, the UE further includes: a handover command receiving unit 104 configured to receive a handover command sent from the access device of the source system for a handover to the primary cell and the secondary cell of the target system; and a multi-carrier handover unit 105 configured to access an access device of the target system according to the handover command to accomplish the handover to the primary cell and the secondary cell of the target system.
An embodiment of the invention further provides a network-side access device as illustrated in FIG. 11 , which includes: a measurement configuring unit 111 configured to configure a terminal with measurement configuration information when determining that the terminal is to switch from a current system to a target system, wherein the measurement configuration information comprises at least two frequencies/cells on at least two frequencies of the target system and a measurement result reporting scheme; an information receiving unit 112 configured to send the measurement configuration information to the terminal and to receive measurement results reported by the terminal; and a handover assisting unit 113 configured to determine a primary cell and a secondary cell of the target system to which a handover is to be performed according to the measurement results and to instruct the terminal to switch to the primary cell and the secondary cell of the target system.
Preferably, the measurement configuration information configured by the measurement configuring unit 111 comprises an additional measurement report indicator used to instruct the terminal to further report a measurement result of a cell on at least one other frequency in addition to a measurement result of a cell on a frequency which triggers a measurement report.
Preferably, the measurement configuration information configured by the measurement configuring unit 111 comprises additional measurement configured on one of the frequencies used to instruct the terminal to report measurement reports of cells with the strongest channel quality on each of additional measurement frequencies related to the one of the frequencies configured with the additional measurement to the access device of the source system when a cell on the frequency triggers a measurement report.
Preferably, the measurement configuration information configured by the measurement configuring unit 111 further comprises the number of frequencies required to be reported, A, and/or the number of cells required to be reported per frequency, B, where A≧2 and B≧1; and/or the measurement configuration information comprises a channel quality threshold.
Preferably, the handover assisting unit 113 is specifically configured to send a handover request to an access device of the target system for a handover to the primary cell and the secondary cell of the target system and to send a handover command to the terminal upon reception of a handover request acknowledgement returned from the access device of the target system, to instruct the terminal to switch to the primary cell and the secondary cell of the target system.
Preferably, the network-side access device is a network access device in a UMTS Terrestrial Radio Access Network, UTRAN, system, a GSM EDGE Radio Access Network, GERAN, system, a Wireless Local Area Network, WLAN, system, a Worldwide Interoperability for Microwave Access, WiMAX, system or a Code Division Multi-Access, CDMA, 2000 system, and the target system is an Evolved UMTS Terrestrial Radio Access Network, E-UTRAN, system.
Those skilled in the art shall appreciate that the embodiments of the invention can be embodied as a method, a system or a computer program product. Therefore the invention can be embodied in the form of an all-hardware embodiment, an all-software embodiment or an embodiment of software and hardware in combination. Furthermore, the invention can be embodied in the form of a computer program product embodied in one or more computer useable storage mediums (including but not limited to a disk memory, a CD-ROM, an optical memory, etc.) in which computer useable program codes are contained.
The invention has been described with reference to flow charts and/or block diagrams of the method, the device (system) and the computer program product according to the embodiments of the invention. It shall be appreciated that respective flows and/or blocks in the flow charts and/or the block diagrams and combinations of the flows and/or the blocks in the flow charts and/or the block diagrams can be embodied in computer program instructions. These computer program instructions can be loaded onto a general-purpose computer, a specific-purpose computer, an embedded processor or a processor of another programmable data processing device to produce a machine so that the instructions executed on the computer or the processor of the other programmable data processing device create means for performing the functions specified in the flow(s) of the flow charts and/or the block(s) of the block diagrams.
These computer program instructions can also be stored into a computer readable memory capable of directing the computer or the other programmable data processing device to operate in a specific manner so that the instructions stored in the computer readable memory create manufactures including instruction means which perform the functions specified in the flow(s) of the flow charts and/or the block(s) of the block diagrams.
These computer program instructions can also be loaded onto the computer or the other programmable data processing device so that a series of operational steps are performed on the computer or the other programmable data processing device to create a computer implemented process so that the instructions executed on the computer or the other programmable device provide steps for performing the functions specified in the flow(s) of the flow charts and/or the block(s) of the block diagrams.
Although the preferred embodiments of the invention have been described, those skilled in the art benefiting from the underlying inventive concept can make additional modifications and variations to these embodiments. Therefore the appended claims are intended to be construed as encompassing the preferred embodiments and all the modifications and variations coming into the scope of the invention.
Evidently those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Thus the invention is also intended to encompass these modifications and variations thereto so long as these modifications and variations come into the scope of the claims appended to the invention and their equivalents. | Disclosed are a method and a device for reporting terminal measurement and for inter-system operation. The method comprises: receiving measurement configuration information transmitted by a source system access device; measuring cells on at least two frequencies within a target system on the basis of the measurement configuration information; on the basis of the measurement configuration information, and when a measurement report is triggered, reporting to the source system access device a measurement result acquired from measuring the cells on at least two frequencies within the target system, and on the basis of the measurement result, the source system access device confirming a main cell and an auxiliary cell for switching for the target system. The present invention assists a network in multicarrier handover between systems, and allows for reduced reporting latency, increased data transmission speed for a terminal switching PS domains between different systems, and enhanced user experience. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a motor vehicle roof with a roof opening located in a fixed roof surface and a cover for closing the roof opening, the cover comprising at least one partially transparent pane and a frame which is connected to the pane and which extends over at least one part of the edge of the pane.
2. Description of Related Art
In these motor vehicles roofs, which can be roofs with a fixed or movable cover, the pane is conventionally a glass pane which is connected by means of a peripheral frame to the motor vehicle roof itself or to a positioning mechanism for positioning the cover. The frame can, moreover, be formed by foaming the pane in place, into which cover a metallic reinforcing or holding frame, for example, inner metal cover sheet, is inserted.
Aside from the glass elements, plastic panes which are cemented to a frame surrounding the pane are furthermore used in vehicle construction, especially for fixed elements.
While glass panes are advantageous in that they can be more easily worked, especially using techniques of foaming in place, it is however disadvantageous that glass covers have considerable inherent weight; this is disadvantageous not only with respect to the total weight of a roof structure, but especially when the cover is a movable cover which then requires a more complex configuration of the components supporting the cover and of the drive of the cover.
Plastic covers are lighter than glass covers, but much more difficult to install than the latter. This is due to the fact that the plastics used for producing vehicle roof covers generally have coefficients of thermal expansion which are very different from those of the metallic reinforcing and holding frame, and therefore, require corresponding movable connections between the pane and the frame, as is explained, for example, in German Patent DE 101 08 527 and corresponding U.S. Patent Application Publication 2002/0113466.
Instead of a corresponding movable mechanical connection, the attempt was made to connect the plastic cover by means of a material connection to the respective frame. For plastic covers using conventional materials, such as polycarbonates, to achieve the stability and durability of the cover required in motor vehicle construction, additional layers of hard material are applied to the outside and inside of the cover and are generally detrimental to a connection to other materials. As a result, the foaming-in-place processes used for glass covers to date are not applicable to plastic covers, and when a plastic cover is cemented to the frame, especially due to the aforementioned major differences with respect to coefficients of thermal expansion, faults and breaks in the cement often occur.
SUMMARY OF THE INVENTION
In view of the aforementioned problems, a primary object of the present invention is to devise a motor vehicle roof of the initially mentioned type which, on the one hand, has a low total weight and is still stable and easy to produce.
This object is achieved in accordance with this invention in that, in a motor vehicle roof of the initially mentioned type, the pane is a plastic pane and the frame is formed by foaming the pane in place, the shape of the pane, in at least one partial area of the connecting region between the pane and the peripheral foam, being chosen such that provision is made for a permanent mechanical connection between the pane and the peripheral foam by means of a positive interlocking connection. In this way, the advantages of easier workability of glass covers can be combined with those of the lower weight of plastic roofs, as a result of the positive interconnection between the plastic pane and the peripheral foam, provision having been made for a permanent, reliable connection between the pane and peripheral foam which does not degrade due to external effects and especially thermal influences.
The positive interlocking provides for a permanent mechanical connection between the plastic pane and the peripheral foam under all operating conditions of the motor vehicle roof. Furthermore, since positive interlocking between the pane and peripheral foam arises from the shape of the pane itself, no additional production or installation steps are necessary to join the pane to the peripheral foam. Rather, the shape elements which provide for the positive interlocking between the pane and peripheral foam are molded integrally to the pane directly as the pane is molded. Then, if the correspondingly molded pane is placed in the foaming-in-place tool and is foamed in place, the peripheral foam material fills the corresponding shape elements and thus provides for positive interlocking between the pane and the peripheral foam.
In particular, the pane can have at least one recess engaged by the peripheral foam. Preferably, in this connection, the shape of the recess is chosen such that the peripheral foam extends behind it. These recesses can be provided in the edge area of the pane on its top and/or bottom and on the face. Furthermore, in this connection, it can be a series of individual recesses or one groove which runs along at least one region of the side edge.
Furthermore, the pane can have at least one elevation or a projection which is embedded in the peripheral foam. Preferably, the shape of the projection is chosen such that the peripheral foam extends behind it. This can be accomplished, for example, in that an essentially L-shaped or T-shaped projection is molded onto the pane which, when it is embedded in the peripheral foam, prevents not only displacement between the pane and the peripheral foam, but also prevents the pane and peripheral foam from moving away from one another.
In another version of the invention, the pane can have an undercut along at least part of its side edge, behind which the peripheral foam extends. This can be accomplished, for example, in that the pane has a recess or a groove along its side edge which is filled with foam material when the pane is foamed in place.
Additionally, along at least part of its side edge, the pane can be encompassed by the peripheral foam; in this case, the pane preferably has a reduced cross section in the part of its side edge encompassed by the peripheral foam, so that a flush roof surface can also be accomplished in the region of the peripheral foam. To reduce the cross section, the pane can have a chamfer, depression and/or a bevel in the part of its side edge in which it is encompassed by the peripheral foam.
It goes without saying that the aforementioned measures can all be combined with one another in any manner, the shaping of the pane which provides for a permanent mechanical connection between the pane and the peripheral foam by means of a positive interlocking connection being provided either in several individual regions of the pane, or it can be made as a geometry which extends essentially over the entire side edge region of the pane.
In another version of the invention, the pane can have an essentially transparent inner region and an essentially opaque edge area so that the areas of the pane in which the mounting elements of the pane are located are covered as seen from the outside and a uniform appearance of the pane results. The opaque edge area can be made, for example, as a blackened region or as a region which is matched in color to the roof surface.
Preferably in this connection, the essentially opaque edge area is molded integrally to the essentially transparent inner region. In particular, the pane can be formed as an essentially transparent pane onto the edge area of which a layer of essentially opaque plastic is molded in one piece. In this connection, the transparent pane can be made such that it essentially completely spans the roof opening, a layer of essentially opaque plastic being molded onto the bottom of the transparent pane. Specifically, the pane can be produced from an essentially transparent polycarbonate material onto the edge area of which a layer of, for example, black polycarbonate material which is essentially opaque is molded in one piece. While it would be fundamentally possible to color the edge area of the transparent plastic pane, for example, by applying a layer of paint, for stability reasons it is preferred that the pane be produced in a two-step production process in which, in a first working step, the actual pane is produced from a transparent material onto the edge area of which, then, an essentially identical, but differently colored material is molded, so that a uniform part results which, with respect to its stability and further workability, is equal to a pane produced from only one material.
As in known, plastic panes used in motor vehicle construction can be provided on its outer side, preferably also on its inner side, with an additional layer of hard material, for example, of polysiloxane in order to increase the abrasion and scratch resistance of the pane. Depending on the choice of the materials used, in this connection, the hard material layer can optionally also be used as an adhesive between the plastic pane and the peripheral foam.
Furthermore, a reinforcing frame, for example, an inside metal cover sheet, can be inserted into the peripheral foam, and in this connection, the outside edge of the inside metal cover sheet can be embedded in the peripheral foam, while the inside edge of the inside metal cover sheet rests against the bottom of the pane. In order to preclude creaking or rattling of the free inner edge of the inside metal cover sheet against the bottom of the pane, between the inner edge area of the inside metal cover sheet and the pane there can be a damping layer, for example, of a rubber, microcellular rubber or textile layer which is applied to the inside metal cover sheet by cementing or by dry coating.
If other attachments of metal or plastic are to be fastened to the cover, such as for example, screens, seals, antennas, cable channels, shade guides, drive cables or the like, they can be embedded directly in the peripheral foam. Alternatively or in addition, holding devices, such as threaded bushings, sleeves, retaining clips and other inserts for mounting these attachments can be embedded directly into the peripheral foam, or recesses for mounting of these attachments can be molded directly into the peripheral foam. If these attachments or holding devices for attachments are embedded in the peripheral foam, they can be inserted directly into the foaming tool during foaming and thus embedded in the peripheral foam.
The peripheral foam can be made from a polyurethane material in the known manner.
Preferred embodiments of the invention are detailed below with reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the upper portion a vehicle;
FIG. 2 is a sectional view of the side edge area of the cover of the motor vehicle roof shown in FIG. 1 ;
FIGS. 3 to 7 are views similar to FIG. 2 of modified embodiments of the cover;
FIG. 8 is a top plan view of the cover shown in FIG. 7 ; and
FIG. 9 is a view similar to FIG. 2 of another modified embodiment.
DETAILED DESCRIPTION OF THE INVENTION
The vehicle shown in FIG. 1 has a roof opening 12 in a fixed roof surface 10 . To close the roof opening, there is a cover 13 which, in the illustrated embodiment, can move along a roof-mounted frame 15 . This invention is used especially on roofs with fixed elements, on sliding roofs, sliding and raising roofs, spoiler roofs, externally guided sliding roofs and the like.
FIG. 2 shows the cover 13 from FIG. 1 in the area of its side edge. The pane 14 , which covers the roof opening and which forms the actual cover, is formed of a transparent pane 16 which is made, for example, from transparent polycarbonate to which a strip 18 of nontransparent material, for example, black polycarbonate, is molded in one piece on its bottom. This pane can be produced by means of a two-stage molding process in which, for example, first a transparent material is placed in a corresponding molding tool, to which a layer of essentially the same, but differently colored material is then molded in a second step so that a one-piece pane of uniform material results. In its edge area, the pane 14 is foamed in place with peripheral foam 20 , for example, of a polyurethane material, the peripheral foam preferably peripherally surrounding the entire edge area of the pane 14 .
To support the pane 14 and to move it on a roof mechanisms (not shown), there is a frame which can be the inside metal cover sheet 22 as shown in FIG. 2 , which is inserted into the foaming-in-place tool at the same time, preferably when the pane 14 is being foamed in place. In this way, the inside metal cover sheet 22 can be connected to the pane 14 by means of the peripheral foam 20 without other production or mounting steps being necessary for this purpose.
In the embodiment shown in FIG. 2 , a positive interlocking connection between the pane 14 and the peripheral foam 20 is established by a chamfer 24 being provided on the transparent part 16 of the pane 14 along its lower edge side, so that after molding the opaque region 18 onto the transparent pane 16 , a groove is formed in the side edge of the pane 14 , preferably a peripheral groove, which fills with foam material when the pane 14 is being foamed in place. Analogously to the undercut of the pane 14 shown here, the pane could also have a groove in its transparent part 16 , or a groove which extends both into the transparent part 16 and also the nontransparent part 18 . In any case, the positive locking between the pane 14 and the peripheral foam 20 produces a strong mechanical link of the pane 14 to the peripheral foam 20 which effectively opposes detachment of the pane from the peripheral foam due to high mechanical or thermal stress.
FIG. 3 shows a modified embodiment of the cover 13 according to FIG. 2 . Here, the pane 14 which has been formed from the transparent pane 16 and the opaque region 18 has a peripheral indentation 26 along its side edge which is filled with the foam material of the peripheral foam 20 .
In the embodiment of the cover 13 in accordance with the invention, as shown in FIG. 4 , the pane 14 which is formed from the transparent plastic pane 16 and the opaque plastic region 18 molded to it in one piece has an edge area 30 with a reduced thickness. In addition, there is a recess 32 in the region with the reduced thickness 30 at a distance from the outside edge of the pane. The outside edge of the pane 14 is foamed in place with polyurethane material, the peripheral foam 20 surrounding the region with the reduced thickness 30 such that the top of the peripheral foam 20 runs flush with the top of the pane 14 .
Furthermore, FIG. 4 shows a configuration of the pane 14 in which there is a projection 28 which extends down on its bottom and from which another projection 34 extends laterally, so that altogether a generally L-shaped projection is formed which is positioned in the foam tool such that the projection becomes embedded in the peripheral foam. As in the preceding embodiments, in the embodiment as shown in FIG. 4 , the pane 14 can also be made such that there are shaping features which provide for positive interlocking with the peripheral foam 20 , here especially, the recess 32 and the L-shaped projection 28 , 34 , in partial regions of the pane, or extending along the entire periphery of the pane.
Furthermore, the outside edge of the inside metal cover sheet 22 is embedded in the peripheral foam 20 so that the inside edge of the sheet metal rests against the underside of the pane 14 . In order to hide the inside metal cover sheet 22 from view from above, the region 18 of the pane produced from the opaque plastic extends just beyond the inside edge of the inside metal cover sheet 22 . Between the inside edge of the inside metal cover sheet 22 and the pane 14 there can also be a damping component 36 which prevents rattling or creaking which could be caused by relative motion between the pane and the inside metal cover sheet. This damping component 36 is preferably an elastic material applied to the top of the inside metal cover sheet 22 , for example, of rubber, microcellular rubber or textile materials, for example, dry coating of the top of the inside metal cover sheet 22 .
FIG. 5 shows another embodiment of a cover 13 in which the outside edge of the pane 14 is encompassed by the peripheral foam 20 . In order to provide space for the peripheral foam 20 around the edge, and still for an altogether flush surface of the cover 13 , along the outside edge of the pane 14 in its transparent part 16 there is a chamfer 38 which is filled with foam material 40 when the pane 14 is foamed in place. If additional attachments such as, for example, screens or shade guides are to be attached to the cover 13 , as is illustrated in FIG. 5 , mountings for these attachments, for example, threaded bushings 52 , can be embedded directly in the peripheral foam 20 . The threaded bushing 52 was inserted into the foaming tool at the same time that the pane 14 was being foamed in place, without the necessity of additional mounting steps.
FIG. 6 shows another embodiment of the cover 13 in which the transparent pane 16 is made as a pane with an essentially uniform thickness, but in which the area 18 of opaque material molded in one piece onto the bottom has a T-shaped projection 48 which is embedded in the PU foam material 20 . Furthermore, FIG. 6 shows an embodiment of the cover in which there is a receiver 42 in a lateral face of the peripheral foam 20 in order to attach a sealing element (not shown) to the cover as is known. These receivers, by means of which attachments such as seals, screens, etc. can be attached to the cover, can be molded in anywhere on the peripheral foam 20 .
FIGS. 7 & 8 show a configuration of the cover 13 in which the positive interlocking between the pane 14 and the peripheral foam 20 is accomplished by a chamfer 38 which runs along the upper outside edge of the transparent pane 16 , and by a plurality of elevations 44 which are provided on the bottom of the pane 14 in its opaque area. As is shown in FIG. 8 , in this connection the elevations 44 can be arranged in a row in succession with a uniform distance between each other and with respect to the side edge of the pane.
Two other measures for making providing a positive interlocking of the peripheral foam 20 and the pane 14 are shown in FIG. 9 . In particular, in this connection, the upper side edge of the pane 14 is beveled in its transparent region 16 , the pane in the area of the bevel 46 being encompassed by the foam material 20 . Furthermore, on the bottom of the pane, there is a recess 50 within the opaque region with an inside cross section which is larger than its opening cross section and which is filled with foam material when the pane is foamed in place. It goes without saying that the recess 50 need not be located only within the opaque region, as in the illustrated example, but, since the pane 14 formed from the transparent pane 16 and the opaque 18 region forms an integral, one-piece component, can also extend into the transparent region 16 . FIG. 9 also shows an embodiment of a cover 13 in which an attachment, here an antenna 54 , is embedded directly into the peripheral foam 20 . Because the antenna 54 is inserted easily into the foaming tool at the same time as the pane 14 is foamed in place, additional installation steps are eliminated.
Besides the above explained versions, numerous other shaping versions are possible, by means of which provision can be made for positive interlocking between the pane and the peripheral foam which then keeps the pane itself fixed on the peripheral foam in all three-dimensional directions when the pane is exposed to repeated high mechanical and thermal stresses. The above described measures can be combined with one another as desired in this connection. | In a motor vehicle with a roof opening ( 12 ) located in a fixed roof surface ( 10 ) and a cover ( 13 ) for closing the roof opening, the cover has an at least partially transparent pane ( 14 ) and a frame which is connected to the pane and which extends over at least one part of the edge of the pane. The pane ( 14 ) is a plastic pane and the frame is formed by in situ foaming ( 20 ) of a foam material onto the periphery of the pane, the shape of the pane, in at least one partial area of a connecting region between the pane and the peripheral foam, is configured such that a permanent mechanical, positive interlocking connection is created between the pane and the peripheral foam. | 1 |
FIELD
The present disclosure relates to systems, methods and apparatus for conveying fluids in subsea functional lines and/or risers. The present disclosure further relates to methods of maintaining such systems.
BACKGROUND
As subsea hydrocarbon production systems have evolved over time, certain challenges have become more problematic. One challenge is that subsea pipeline systems now cover greater areas, therefore the pipelines must traverse greater distances. Pipeline system designers would like to have greater flexibility to utilize various sizes and types of subsea pipeline, particularly as systems become larger and more complex. Another challenge is that as pipeline is laid in deeper and deeper water, the weight of the pipeline can create too much tension to safely install. Another challenge is that certain subsea production fields necessitate subsea pipeline crossing difficult geographical formations, including canyons, scarps and rough terrain. In these situations, it would frequently be desirable to utilize a flexible and/or lighter weight pipe or conduit for at least a portion of the pipeline system.
A consideration which often limits the pipeline system designer's ability to design pipeline systems adapted to such challenges is the piggability of the lines in the systems. It would be desirable to have the ability to provide subsea pipeline systems including transitions between various types of pipe as well as various pipe diameters; however such systems are not piggable with current technology. It would be desirable to provide such systems while retaining the ability to effectively pig the lines of the systems.
SUMMARY
In one aspect, a system for conveying fluids is provided which includes at least one riser having a riser diameter attached to an offshore production platform for conveying fluid to the production platform and at least one functional line located on the seabed having a functional line diameter in fluid communication with the at least one riser for conveying fluid to the at least one riser. The functional line diameter and the riser diameter differ by more than 2 standard API 5L pipeline diameters.
In another aspect, a system for conveying fluids is provided which includes a subsea functional line including a first functional line and a second functional line in fluid communication with one another. The diameters of the first and second functional lines differ by more than 2 standard API 5L pipeline diameters.
In another aspect, a method for maintaining either of the above systems is provided which includes pigging the system.
In another aspect, a wye apparatus including a junction of at least three sections of functional line is provided wherein the diameters of two of the at least three sections of functional line differ by more than 2 standard API 5L pipeline diameters.
In yet another aspect, a pipeline crossing termination is provided which includes a subsea structure capable of connecting to a first functional line and a second functional line or to a functional line and a riser such that the first functional line and the second functional line or the functional line and the riser are placed in fluid communication with one another. A pig launcher can be attached to the subsea structure such that a pig can be launched into the system of the first functional line and the second functional line or of the functional line and the riser. The diameters of the first and second functional lines or of the functional line and the riser differ by more than 2 standard API 5L pipeline diameters.
DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of the present invention will become better understood with reference to the following description, appended claims and accompanying drawings where:
FIG. 1 is a perspective view illustrating a pipeline connection terminal according to one exemplary embodiment wherein the pipeline connection terminal includes a wye.
FIGS. 2A and 2B are perspective views illustrating a pipeline connection terminal according to another exemplary embodiment wherein the pipeline connection terminal includes a pig launcher.
FIGS. 3A and 3B are perspective views illustrating a pipeline connection terminal according to another exemplary embodiment wherein the pipeline connection terminal includes coiled tubing interfaces.
FIG. 4 is a perspective view illustrating a pipeline connection terminal according to another exemplary embodiment in which the pipeline connection terminal includes a booster pump.
FIG. 5 is a perspective view illustrating a pipeline connection terminal according to another exemplary embodiment wherein the pipeline connection terminal includes a pig launcher.
FIGS. 6A and 6B are perspective views illustrating a pipeline connection terminal according to another exemplary embodiment wherein the pipeline connection terminal includes a wye and a pig launcher.
FIGS. 7A and 7B are perspective views illustrating a pipeline connection terminal according to another exemplary embodiment wherein the pipeline connection terminal includes multiple wyes and a pig launcher.
FIGS. 8-11 are illustrations of subsea pipeline systems utilizing pipeline connection terminals according to embodiments disclosed herein.
DETAILED DESCRIPTION
Embodiments are described hereinafter in which conduits for conveying fluids of differing conduit type and/or large diameter differences are utilized in a subsea production system in such a way that the conduits are in fluid communication with one another and the system is piggable.
As used herein, the terms “pipeline,” “pipe,” “functional line,” “line,” and “conduit” may be used interchangeably to refer to conduits for conveying fluids which may be utilized in subsea hydrocarbon production systems. The term “riser” refers to a conduit for conveying fluids extending from the seabed to a surface location, such as a platform or vessel.
In some embodiments, a system for conveying fluids is provided which includes at least one riser attached to an offshore production platform for conveying fluid to the production platform and at least one functional line located on the seabed in fluid communication with the at least one riser for conveying fluid to the at least one riser. In some embodiments, the riser can have a length of at least 10 m, even of 10 m to 5000 m. The functional line on the seabed can be a subsea pipeline for conveying oil and gas production fluids. Alternatively, the functional line on the seabed can be used to convey other fluids known to be useful in the production of oil and gas. For instance, such functional lines can be selected from oil recovery gas lines, gas lift lines, water lines, well service lines, well kill lines, scale squeeze lines, methanol lines, MEG lines and lines for tertiary recovery fluid, as will be familiar to those skilled in the art.
The riser and the functional line can be different types of pipe. For instance, the functional line can be a rigid pipe while the riser can be an engineered pipe. The engineered pipe can be bonded flexible pipe, unbonded flexible pipe or multilayered composite pipe.
Advantageously, the functional line diameter and the riser diameter differ by more than 2 standard API 5L pipeline diameters. More specifically, the functional line diameter can be, for example, at least 10.2 cm, even from 10.2 cm to 102 cm. The riser diameter can be, for example, at least 5.1 cm, even from 5.1 cm to 91.4 cm. Thus, systems including a combination such as, for example, a riser having a nominal pipe size (NPS) of 20 in (outer diameter of 50.8 cm) in fluid communication with a functional line having a NPS of 40 in (outer diameter of 101.6 cm) can be provided by the present disclosure. The present disclosure also provides other combinations, including, as nonlimiting examples, a riser having a NPS of 16 in (outer diameter of 40.6 cm) in fluid communication with a functional line having a NPS of 3½ in (outer diameter of 8.89 cm); and a riser having a NPS of 6⅝ in (outer diameter of 16.8 cm) in fluid communication with a functional line having a NPS of 14 in (outer diameter of 35.6 cm).
A pipeline crossing termination can be located on the seabed between the functional line and the riser. The term “pipeline crossing termination” as used herein refers to a subsea structure such as a manifold capable of connecting to multiple lines and/or risers such that the lines and/or risers are placed in fluid communication with one another. In some embodiments, a pipeline crossing termination is located between the at least one riser and the at least one functional line on the seabed. The pipeline crossing termination allows lines and/or risers of different types and diameters differing by more than 2 standard API 5L pipeline diameters to be connected.
In some embodiments, a system for conveying fluids is provided which includes at least two functional lines in fluid communication with one another, i.e., at least a first functional line located on the seabed and a second functional line located on the seabed. The first and second functional lines can be different types of pipe selected from rigid pipe and engineered pipe. The diameters of the first and second functional lines differ by more than 2 standard API 5L pipeline diameters. A pipeline crossing termination, as described above, can be located on the seabed between the first and second functional lines.
FIG. 1 illustrates a system 100 according to one exemplary embodiment wherein a first functional line 114 is connected to second and third functional lines 112 and 110 via a wye 104 . The functional lines 114 and 110 in the embodiment illustrated differ by more than 2 standard API 5L pipeline diameters, where 114 and 112 are rigid pipe and 110 is a flexible pipe. A mudmat 102 supports the wye 104 . Also provided are valves 106 and a pipeline connector 108 as appropriate, as would be apparent to one skilled in the art.
In some embodiments, the pipeline crossing termination, connecting either the at least one riser and at least one functional line located on the seabed or the at least first and second functional lines, can further include a subsea pig launcher capable of housing at least one pig and introducing a pig into the system. The pig can travel in any direction and stop at any point through the system. Through pigging the system, the functional line(s) and/or the riser(s) of the system can be maintained. Pigs capable of passing through pipeline systems have a multiple diameters and differing types of pipe are disclosed in co-pending patent application Ser. No. 13/738,740, the contents of which are incorporated herein by reference.
In one embodiment, FIGS. 2A and 2B illustrate a pipeline crossing termination connecting a large diameter pipeline 114 with two smaller diameter pipelines 110 . FIG. 2A is an exploded view, and 2 B illustrates a system when pig launcher/receiver 120 is connected to the pipeline system so that a pig 121 can be inserted or removed from the system. Pig launcher/receiver 120 is oriented vertically in this embodiment. An ROV interface 116 can be provided to assist with pig launching and receiving operations. In the system illustrated, wye 104 includes four pipeline branches. Coiled tubing interfaces 118 can be provided to allow the insertion of coiled tubing into the pipeline.
In some embodiments, to be described hereinafter, the pig 121 can further include one or more smaller pigs 122 contained therein which can be released into the smaller diameter pipelines 110 .
FIGS. 3A and 3B illustrate a pipeline crossing termination connecting a single large diameter pipeline 114 with a single smaller diameter pipeline 110 . In the particular embodiment illustrated, two wyes 104 are used. Two coiled tubing interfaces 118 are also included. FIG. 3A is an exploded view, and 3 B illustrates a system in which the coiled tubing interfaces 118 are connected to the pipeline system.
FIG. 4 illustrates a system according to one exemplary embodiment in which a single large diameter pipeline 114 is in fluid communication with a single smaller diameter pipeline 110 . In this particular embodiment, a booster pump 124 is further provided for pumping fluids conveyed within the functional lines. The pipeline crossing termination can further include any of a number of other known components for use in subsea production systems. For example, it may be convenient to include a gas-liquid separator mounted on the pipeline crossing termination for separating gas and liquid fluids conveyed within the functional lines connected thereto. Other subsea system components as would be apparent to one skilled in the art may also be included.
FIG. 5 illustrates a system according to one exemplary embodiment in which a pig launcher/receiver 120 oriented horizontally is connected to the pipeline system so that a pig 121 can be inserted or removed from the system. Again, as will be described further hereinafter, the pig 121 can further include one or more smaller pigs 122 contained therein which can be released into the smaller diameter pipelines 110 .
FIGS. 6A (exploded view) and 6 B (connected view) illustrate a system according to another exemplary embodiment in which a pig launcher/receiver 120 oriented vertically is connected to the pipeline system so that a pig 121 can be inserted or removed from the system. Again, as will be described further hereinafter, the pig 121 can further include one or more smaller pigs 122 contained therein which can be released into the smaller diameter pipelines 110 .
FIGS. 7A (exploded view) and 7 B (connected view) illustrate a system according to yet another exemplary embodiment in which a pig launcher/receiver 120 oriented vertically is connected to the pipeline system so that a pig 121 can be inserted or removed from the system. Again, as will be described further hereinafter, the pig 121 can further include one or more smaller pigs 122 contained therein which can be released into the smaller diameter pipelines 110 .
In some embodiments, the system can also include a third functional line such that the second functional line is located between the first and third functional lines. For example, the second functional line can cross a section of rough terrain, a subsea scarp or cliff, or a subsea canyon. Each of the first, second and third functional lines can have different diameters, or two of the three functional lines have diameters that differ by more than 2 standard API 5L pipeline diameters.
In some embodiments, the system includes two pipeline sections generally running in parallel with one another. This is particularly advantageous when the tension involved in installing a single large diameter line would be too great, thus prohibiting installation of a single pipeline. The tension can be further reduced by the use of lighter weight flexible conduit(s) in place of conventional rigid pipe.
In some embodiments, the system can include two generally parallel risers connected to the functional line located on the seabed and also connected to the offshore production platform. Again, the two generally parallel risers can be lighter weight flexible pipe such that the stress on the connection with the platform is not excessively high.
In some other embodiments, the system includes two generally parallel functional lines located on the seabed connected to a riser which is attached to an offshore production platform. Such a system can be used for various reasons, including providing flexibility to transport production fluids from multiple sources to a single riser.
The first and second and optional third functional lines can be subsea pipeline conveying oil and gas production fluids. Alternatively, the functional lines can be selected from oil recovery gas lines, gas lift lines, water lines, well service lines, well kill lines, scale squeeze lines, methanol lines, MEG lines and lines for tertiary recovery fluid.
The first and second and optional third functional lines can be different types of pipe, wherein the types of pipe are selected from rigid pipe and engineered pipe. The engineered pipe can be bonded flexible pipe, unbonded flexible pipe or multilayered composite pipe.
The diameters of two of the first and second and optional third functional lines differ by more than 2 standard API 5L pipeline diameters. One of the functional line diameters can be at least 10.2 cm, even from 10.2 cm to 102 cm. Another of the functional line diameters can be at least 5.1 cm, even from 5.1 cm to 91.4 cm. Other combinations of pipeline diameters can be used. Thus, systems including a combination such as, for example, a functional line having a nominal pipe size (NPS) of 40 in (outer diameter of 101.6 cm) in fluid communication with a functional line having a NPS of 20 in (outer diameter of 50.8 cm) can be provided by the present disclosure. The present disclosure also provides other combinations, including, as nonlimiting examples, a functional line having a NPS of 40 in (outer diameter of 101.6 cm) in fluid communication with a functional line having a NPS of 16 in (outer diameter of 40.6 cm); a functional line having a NPS of 3½ in (outer diameter of 8.89 cm) in fluid communication with a functional line having a NPS of 6⅝ in (outer diameter of 16.8 cm); and a functional line having a NPS of 14 in (outer diameter of 35.6 cm) in fluid communication with a functional line having a NPS of 20 in (outer diameter of 50.8 cm).
The present disclosure is particularly useful in certain scenarios. FIG. 8 illustrates a subsea pipeline system 300 in one such scenario, in which pipeline crossing terminations 304 and 306 are installed on the seabed on each side of a subsea canyon. On the higher ground adjacent the canyon on each side, pipelines 308 and 310 can extend away from the c's anyon in either direction. Pipelines 308 and 310 can be larger diameter functional lines, typically rigid pipe, although other types of pipe can also be used in such a system. Extending between pipeline crossing terminations 304 and 306 can be flexible engineered pipe. Illustrated are two generally parallel functional lines 302 and 302 ′ extending across the canyon in parallel.
FIG. 9 illustrates a similar scenario, in which pipeline crossing terminations 304 and 306 are installed on the seabed on each side of a subsea scarp or subsea cliff, rather than a canyon as described above.
FIG. 10 illustrates another scenario, in which a pipeline crossing termination 304 is installed on the seabed at a shallower water depth, and the two parallel functional lines 302 and 302 ′ extend into progressively deeper water.
FIG. 11 illustrates another scenario, in which a pipeline crossing termination 304 is installed on the seabed at the base of a marine riser 308 . In this embodiment, the pipeline crossing termination 304 acts to connect the two parallel functional lines 302 and 302 ′ on the seabed with the riser 308 , which in turn is connected to an offshore production platform 400 .
In one embodiment, a novel piggable pipeline wye apparatus, also referred to as a “wye apparatus” or simply a “wye,” is provided. The wye apparatus includes a junction of at least three sections of functional line wherein the diameters of two of the at least three sections of functional line differ by more than 2 standard API 5L pipeline diameters. The wye can be mounted on the subsea structure of the pipeline crossing termination. In one embodiment, two of the at least three sections of functional line of the wye are moveable to allow a section of functional line containing a pig to be removed from the flow path.
The pipeline crossing termination may be capable of isolating at least two of the functional lines connected to the pipeline crossing termination from one another, thus enabling fluid flow to be ceased in at least a portion of the pipeline system as may be needed for inspection or repair. This may be accomplished by closing valves on the pipeline crossing termination, for example. Other means will be apparent to those skilled in the art.
Where permitted, all publications, patents and patent applications cited in this application are herein incorporated by reference in their entirety, to the extent such disclosure is not inconsistent with the present invention.
Unless otherwise specified, the recitation of a genus of elements, materials or other components, from which an individual component or mixture of components can be selected, is intended to include all possible sub-generic combinations of the listed components and mixtures thereof. Also, “comprise,” “include” and its variants, are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that may also be useful in the materials, compositions, methods and systems of this invention.
From the above description, those skilled in the art will perceive improvements, changes and modifications, which are intended to be covered by the appended claims. | Disclosed are pipeline systems, methods and apparatus for handling fluids in offshore oil and gas production. The systems disclosed allow subsea functional lines having diameters which differ by more than 2 standard API 5L pipeline diameters to be placed in fluid communication in such a way that the systems are piggable. Pipeline connection terminations are installed to facilitate connection of such functional lines. Such systems offer solutions to problems related to installing subsea pipeline in rough terrain, over subsea canyons and subsea scarps, installing marine risers, and long tiebacks. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to a system for removing mercury from wastewater, and, more particularly, to a system that separates particulate such as mercury-bearing amalgam from water after use in dental procedures and to the disposal of the separated mercury-laden material after collection in the system.
[0003] 2. Description of Prior Art
[0004] When an amalgam filling is removed from a patient's tooth, it is normally ground away by some sort of dental burr. This generates a multitude of amalgam particles that contain a large amount of mercury. These particles, and the mercury with them, are normally discharged into the sanitary sewer along with the water used to cool the dental burr and flush the particles out of the patient's mouth. The normal municipal waste treatment plant is not designed to remove mercury from wastewater, so therefore, mercury is discharged into the local streams and estuaries where it is adsorbed and ingested by the plants and animals within these bodies of water. When these plants and animals are consumed further up the food chain, higher life forms, including humans, become susceptible to mercury poisoning.
[0005] The presence of mercury in dental wastewater has been known since the inception of mercury-based amalgam. The problems associated with the increasing levels of mercury in estuaries connected to municipal waste water systems have also been known for many years. However, it has only been recently that the increasing level of mercury in the world's waters has been directly associated with dental wastewater. It is even more recent that any effort to stem these increasing mercury levels has been initiated. These efforts to eliminate mercury from dental wastewater streams and subsequently the natural water sources of the world include:
[0006] U.S. Pat. No. 5,795,159 (Ralls et al.), Aug. 18, 1998, where there is an initial gravity-dependent separation of the gaseous phase from the liquid and solid phase, followed by mechanical barrier-dependent separation of the liquid phase from the solid phase, which in turn is followed by a remixing of the gaseous phase with the liquid phase that is then wasted to drain. To dispose of the collected solid waste, the system is opened, the filter is either manually cleaned out or sealed up and replaced. This type of system is intended for multiple stations to feed into and to last for several days. While the device of Ralls et al. will separate the mercury-laden particles from the liquid and gaseous phases, it does not necessarily eliminate or reduce the mercury, but in fact it most likely will increase the amount of mercury dissolved in the wastewater. This lack of reduction and probable increase in dissolved mercury stems from the amount of time the water remains in contact with the mercury-laden particles trapped by the filter, which may not be changed for several days. With the particles remaining in water during the closed hours of the office, the mercury is more likely to go into solution in the water than if the filter is changed on a daily bases at the end of work hours.
[0007] There are numerous other devices that have been proposed to separate mercury from the dental waste stream; however, for the most part, their main purpose was the reclamation of metals rather than eliminating mercury pollution at the source. Most prior art devices allow mercury-laden particles to remain in water for extended periods of time. This allows the mercury to become dissolved into the water, malting abatement all the more difficult. For the most part, mercury that is dissolved into water is completely ignored by the mechanisms and processes of the prior art.
[0008] What these prior efforts have in common, other than removal of mercury-laden particles, is that mercury dissolved in water is not addressed, mercury vapor is not addressed, safe handling of the collected mercury-laden material is not addressed, and timely change out or cleaning of the system is not addressed.
[0009] Therefore, a need exists for an affordable, safe to handle, totally disposable system that will reduce the contact time of mercury-laden particles with water, reduce the amount of mercury vapor released to the air, allow for timely and simple replacement, and restore the confidence of the dental office worker that their exposure, their patient's exposure, and the environment's exposure to mercury is greatly reduced.
BRIEF SUMMARY OF THE INVENTION
[0010] The disclosed and claimed embodiments of the invention are directed to a system that primarily removes mercury-laden particles from a dental waste stream. The embodiments of the present invention also have application in the removal of various other forms of mercury found in the solid, liquid, and gaseous phases. The system is preferably disposable, but may find application in a form where the consumables are changed without disposing of the housings and connections. While the embodiments of the invention are configured to reduce the amount of mercury contamination finding its way into the natural waters, the utility of the invention is such that it will also provide a safer atmosphere in the immediate dental office.
[0011] In one embodiment, a system for filtering mercury and mercury-laden particles is provided that includes a housing having an internal chamber, an inlet in fluid communication with the chamber, and a filter in the chamber. In accordance with an aspect of this embodiment, the filter includes a course filter, an abatement filter, and an ion exchange filter. In accordance with another aspect of this embodiment, the filter includes a course screen, an abatement filter, such as a carbon block, and a disinfectant filter, each separated by a space in the chamber.
[0012] In another embodiment, the chamber is formed inside a cartridge that is removably mounted inside the housing to facilitate disposal of the filtered material.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0013] The features and advantages of the present invention will be more readily appreciated as the same become better understood from the following detailed description when taken in conjunction with the accompanying drawings, wherein like numbers designate like elements, and wherein:
[0014] [0014]FIG. 1 is a cross-sectional illustration of one embodiment of the system with standard hose-barb type connections and simplified media configuration.
[0015] [0015]FIG. 2 is a cross-sectional illustration of another embodiment of the invention with quick-disconnect type connections and complex media configuration.
[0016] [0016]FIG. 3 is a cross-sectional illustration of an alternative embodiment of the invention that will allow quick, easy, and safe change-out of the media and trapped mercury without disposal of the overall housing and connecting elements.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Referring to FIGS. 1 and 2, there is shown preferred embodiments of a mercury abatement device 1 with standard hose barb type fittings and a mercury abatement device 2 with quick disconnect fittings, both of which are totally disposable. In normal operation, with an external vacuum source (not shown) supplying the motive force, the dental debris, including mercury-laden particles, which are generated by grinding, shaping, filling, or other operation, liquids such as bodily fluids and water used to cool grinding tools and to flush out debris, and air, are picked up by the dental aspiration hand piece (not shown), or other type instrument (not shown), fed through flexible tubing (not shown), through the inlet hose barb fitting 12 for the device 1 or through an inlet quick disconnect fitting 46 , which latches to the mating fitting (not shown) and which is sealed by an inlet quick disconnect O-ring 48 for the device 2 , and pass through an inlet check valve assembly 14 .
[0018] An inlet check valve ball seal 16 , which is normally held in the closed position by an inlet check valve spring 18 , opens due to the force of the vacuum and its resulting flow, allowing the mixed phase flow of solids, liquids, and gases to enter an inlet chamber 20 , which is formed by a canister housing 22 , the canister end closure 24 , and the particulate filter media 26 in FIG. 1 or a coarse separation screen 50 in FIG. 2.
[0019] In FIG. 1, the bulk of the solid phase portion of the flow is trapped by a media 26 , which allows only those particles smaller than the pore size of the media 26 , the liquids, and the gases to pass through. In one embodiment the media 26 is a course particle screen or particulate filter known in the art. The next encounter is with a first abatement media 28 , which is preferably an activated carbon block, but may be of other suitable material, which should trap any solid particles that pass through the particulate filter media 26 , thus resulting substantially in only a liquid and gaseous phase flow, and also which will absorb the bulk of the dissolved and gaseous mercury which has gone into solution in the liquids or mixed with the other gases. The next encounter is with the second abatement media 30 , which is preferably an ion exchange material that will further reduce the amount of mercury in the continuing flow of liquids and gases. A filter material support 32 serves to keep the filter and abatement media from adding to the flow as it passes through the device.
[0020] In FIG. 2 a system is depicted in which the bulk of the solid phase is removed from the flow by a coarse separation screen 50 , which allows the particulate matter to migrate to the lower portions of the inlet chamber 20 . The conical shape of screen 50 , shown as a triangular shape in the cross-sectional view of FIG. 2, and the void created by a coarse particle buffer space 52 cooperate to provide a less impeded flow for the liquid and gaseous phases. This results in less contact time of the liquids and gases with the mercury-laden solids, thus resulting in less mercury being picked up and mixed or dissolved into the flow, resulting in less work for the subsequent abatement medias.
[0021] The function of an additional filtration/abatement media 54 is identical to that of the medias 28 and 30 and the support 32 shown in FIG. 1. It should be noted that the media and screen configuration of FIG. 2 and that of FIG. 1 may be interchanged or intermixed, or may be in the form of a mixed media rather than stratified, to provide an optimum configuration.
[0022] The next portion of the device to be encountered is the outlet chamber 34 , which provides a place for the liquid and gaseous phase, that have been stripped of solid phase debris and dissolved and entrained mercury to quickly exit the filtration media, thus again reducing contact time with mercury-containing substances, and resulting in less mercury dissolved in the water. In FIG. 2, the next encounter is with a disinfection media 56 , which, being in the form of oxidant available in dry or other form which can be somewhat uniformly dissolved or eroded by the water stream, will provide a means of disinfecting the water stream that could be contaminated with a multitude of viruses, bacteria, or other microbial contaminants emanating from the patient.
[0023] Next, again as shown in FIG. 2, the liquid and gaseous phases flow through an outlet passage 58 . It should be noted that the disinfection media 56 and a passage 58 could work together or separately in the embodiment shown in FIG. 1.
[0024] Finally, in FIG. 1, the flow enters the outlet check valve assembly 36 , where the outlet check valve ball seal 38 depresses the outlet check valve spring 40 , due to the force of the vacuum and flow, and exits through the outlet hose barb fitting 42 , which is connected to a tubing (not shown) which is itself connected to a vacuum source (not shown), a liquid/gaseous phase separation mechanism (not shown), and subsequent sewage drain (not shown).
[0025] In FIG. 2, after exiting the passage 58 , the flow enters the outlet quick disconnect fitting 60 , which when connected to a mating fitting (not shown), which is subsequently connected to the sewage drain as described for FIG. 1, causes an outlet quick disconnect actuator 68 to depress an outlet quick disconnect ball seal 64 against an outlet quick disconnect spring 62 . This allows the flow to pass through the disconnect 60 into the mating fitting (not shown), which is held in place by outlet quick disconnect locking balls 70 , which are either held in place or released to allow disconnection by the outlet quick disconnect release sleeve 66 .
[0026] Prior to and after use, a connection seal cap 44 is placed over the fittings 12 , 42 , and 46 . Since the disconnect fitting 60 is shown as a female, self-sealing type of fitting, it would not normally require a seal cap; however, it is envisioned that a non-sealing type fitting could be appropriate, in which case a male sealing plug (not shown) would be in order.
[0027] [0027]FIG. 3 shows an alternative embodiment, which consists of a mercury abatement device housing 3 and a mercury abatement device disposable cartridge 4 . In this embodiment, the flow enters through the fitting 46 and flows through a passage in an outer housing top 72 , which is sealed to an outer housing bottom 80 by an outer housing O-ring seal 76 and is held in place by an outer housing latch mechanism 78 , which may be of any type of suitable mechanism such as toggle latches, threads, bayonets, etc. The top 72 is sealed to the cartridge 4 by the housing-to-cartridge top seal 74 , which can be of any suitable type of compression seal. It is sandwiched between the top 72 and the cartridge top 84 . The flow continues through a passage in the top 84 and through the cartridge inlet check valve 82 , which is shown as a reed type valve, but may be of the type shown on FIG. 2 or any other suitable type check valve. The flow and processes through the remainder of the cartridge 4 and the housing 3 are identical to those for FIGS. 1 and 2 with the exception of the cartridge outlet check valve 90 , which may be identical to the valve 82 , and the housing-to-cartridge bottom seal 88 , which in turn may be identical to the seal 74 and is sandwiched between the cartridge bottom 86 and the housing bottom 80 .
[0028] The top 84 is shown as forming a keying mechanism to ensure proper installation of the cartridge 4 ; however, numerous other types of keying mechanisms would be appropriate.
[0029] While the principles of the invention have now been described in connection with the illustrated embodiments, there will be immediately obvious to anyone skilled in the art, many modifications of structure, arrangements, proportions, combinations, the elements, materials and components used in the practice of the invention and otherwise, which are particularly adapted for specific environments and operation requirements without departing from those principles. Such modifications are intended to come within the scope of the claims that follow and the equivalents thereof. | A system to remove mercury and mercury-containing particles from waste water prior to entrance into a municipal sewage system. In one form, the system includes a housing having an interior chamber with an inlet and outlet in fluid communication in the chamber, and a filter inside the chamber. The filter, in one embodiment, includes a course filter, an abatement filter, and an ion exchange filter. The chamber and filter may be formed in a removable cartridge mounted in the housing to facilitate safe handling and disposal thereof. | 2 |
BACKGROUND OF THE INVENTION
In today's need for more space-efficient furniture for use in homes having limited living quarter space, particularly bedroom space, the platform bed has become increasingly popular. The conventional platform bed usually consists of a pedestal portion which sits on the floor of the bedroom and totally encloses the floor space upon which it rests, and a platform portion which is supported by the pedestal portion in an elevated position above the floor; the conventional box spring and mattress combination or mattress along being supported by the platform portion. The pedestal and platform portions of the bed include side and end frame members connected by suitable coupling members to form a rectangular structure. Heretofore, the coupling members have included fasteners such as screws, bolts, nails and the like, which required special tools and some expertise in carpentry on the part of the assembler in handling the tools to construct the bed.
In order to facilitate the assembly or disassembly of platform beds by a person having limited carpentry or mechanical ability, the platform bed of the present invention has been devised and comprises, essentially, the conventional pedestal and platform portions having corner connectors for frictionally connecting the side and end frame members to each other. A novel corner connector is provided for connecting the side and end frame members of the platform portion of the bed, and a plurality of transversely extending channel members extend between the side frame members of the platform portion for supporting a plurality of horizontally disposed panel members upon which the box spring and/or mattress are supported.
By the construction and arrangement of the platform bed of the present invention, the various components can be easily connected without the need for any tools, resulting in a rigid structure which maintains its rigidity even after many times of assembly and disassembly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the platform bed of the present invention;
FIG. 2 is a view taken along line 2--2 of FIG. 1;
FIG. 3 is a view taken along line 3--3 of FIG. 1;
FIG. 4 is a view taken along line 4--4 of FIG. 1;
FIG. 5 is a perspective view of the novel connector of the present invention;
FIG. 6 is a fragmentary, top plan view of the pedestal and platform frame members;
FIG. 7 is a view taken along line 7--7 of FIG. 6; and
FIG. 8 is a perspective view showing the assembly of an end of a channel member on a bracket on a side frame member.
DETAILED DESCRIPTION
Referring to the drawings and more particularly to FIG. 1 thereof, the platform bed of the present invention comprises a pedestal portion 1, a platform portion 2, which is supported in an elevated position above the floor by the pedestal portion, and a box spring and/or mattress combination 3 which is supported by the platform portion 2.
As will be seen in FIGS. 2, 4 and 6, the pedestal portion 1 comprises a pair of spaced, parrallel, longitudinally extending side frame members 1a, 1b and a pair of spaced, parallel, transversely extending end frame members 1c, 1d, the ends of the side frame members being connected to a respective end of the end frame members by a conventional corner connector 1e, of the type shown in U.S. Pat. No. 3,989,397, to thereby form a rectangular structure. The inner surfaces of the longitudinally extending frame members 1a, 1b are provided with spaced strip members 1f, 1g forming a track or groove for receiving a transversely extending partition 1h.
Referring to FIGS. 2, 3 and 6, the platform portion 2 of the bed comprises, a plurality of transversely extending, inverted channel members 10 having flange portions 2b. The inverted channel members 10 are seated on the top edges of the pedestal end frames 1c and 1d and the partition 1h, and the web portion 2a of each channel member is provided with a depending tab member 2c which is received in a correspondingly shaped slot 1i provided in the top edges of the end frame members 1c, 1d and partition 1h, to thereby prevent the channel members from sliding transversely when mounted in the operative position.
As will be seen in FIGS. 6, 7 and 8, the ends of each transversely extending channel member are adapted to be supported by brackets 4 secured to the inner faces of a pair of spaced, parallel, longitudinally extending frame members 2d, 2e forming a part of the platform portion 2. Each bracket 4 comprises a right angle member having the vertical leg 4a fastened to the respective side frame 2d, 2e by suitable fasteners 4b. A pair of spaced, parallel ears 4c are integrally connected to the leg 4a and extend normal thereto inwardly from the inner face of the side frame. The lower edges 4d of the ears 4c are spaced above the horizontal leg portion 4e of the bracket 4, for frictionally receiving the flange portions 2b of the channel member 2a, and the ears 4c are spaced sufficiently from each other to frictionally receive the legs of the inverted channel therebetween, as shown in FIG. 7.
In order to hold the channels 2a and brackets 4 in frictional engagement, a pin 4f can be inserted through aligned apertures 4g, 4h provided in the horizontal leg 4e of the bracket 4 and the flange portion 2b of the channel, respectively.
To complete the construction of the platform portion 2 of the bed, as will be seen in FIGS. 2, 3, 5 and 6, a pair of spaced, parallel, transversely extending end frame members 2f and 2g are connected to the ends of the longitudinally extending frame members 2d, 2e by novel corner connectors 5. Each corner connector comprises a one-piece member having a body portion including a pair of arms 5a, 5b disposed at a right angle to each other to conform to the inside corner of the platform portion formed by the side frames 2d, 2e and adjacent end frames 2f and 2g. The outer edges of each of the arms 5a, and 5b are provided with a pair of divergent or V-shaped fingers 5c, 5d, the major axis thereof extending normal to the longitudinal axis of the respective arms. The divergent fingers 5c, 5d are slidably received within corresponding-shaped grooves or recesses 2h, 2i formed in the platform portion side and end frame members, and are frictionally retained therein to hold the side and end frame members together.
Referring to FIGS. 2 and 6, shelf members 2j, 2k are secured to the inner faces of the end frame members 2f and 2g, respectively. A panel 6 is positioned on the shelf member 2j and oppositely facing flange portion 2b of the adjacent channel member, and another panel 7 is similarly mounted on the opposite end of the platform portion by being seated on the shelf 2k and adjacent flange portion 2b. Additional panels 8 and 9 are supported by the remaining flange portions 2b of the inverted channels 10, all the panels extending transversely between the side frame members 2d, 2e to thereby provide a horizontal surface for supporting the mattress assembly 3.
To assemble the platform bed of the present invention, the pedestal portion 1 is first constructed employing the corner connectors 1e for connecting the side and end frame members 1a, 1b, 1c, 1d. The partition 1b is then inserted into the track formed by the strips 1g, 1f. The inverted channel members 10 are then mounted on the top edges of the end frames 1c, 1d and partition 1h in such a manner that the depending tabs 2c are received in the respective slots 1i. The platform side frames 2d, 2e and associated brackets 4 are then connected to the ends of the channel members 10 as shown in FIGS. 7 and 8. The platform portion end frames 2f and 2g are then connected to the side frames 2d, 2e by inserting the corner connectors 5 vertically into the recesses. For convenience, the arm 5b may be affixed to the end frame 2f so that both the end frame 2f and connector 5 are moved in a vertical direction to connect the end frame to the side frames.
After the platform side and end frames are connected, the panels 6, 7, 8 and 9 are positioned as shown in FIG. 2 to provide a horizontal surface for receiving the mattress assembly 3.
From the above description, it will be readily apparent to those skilled in the art that the construction and arrangement of the various components of the platform bed of the present invention results in a construction which facilitates the assembly and disassembly of the bed without the necessity of screws, nails, adhesive or the use of special tools, and provides a platform bed which is sturdy in construction and not likely to get out of order even after long and continued use.
It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or scope of the subjoined claims. | A platform bed having a pedestal portion supporting a platform portion upon which the mattress is positioned; corner connectors are provided for connecting the side and end frame members of the pedestal and platform portions and transversely extending channel assemblies extend between the side frame members of the platform portion for supporting panel members upon which the mattress rests. The corner connectors and channel assemblies facilitate the assembly of the bed without the need for special tools or fasteners such as screws, bolts and the like. | 8 |
CROSS-REFERENCE TO RELATED COPENDING PATENT APPLICATIONS
The following patent applications, which are assigned to the assignee of the present invention and filed concurrently herewith, cover subject matter related to the subject matter of the present invention: “SPEECH COMMAND INPUT RECOGNITION SYSTEM FOR INTERACTIVE COMPUTER DISPLAY WITH MEANS FOR CONCURRENT AND MODELESS DISTINGUISHING BETWEEN SPEECH COMMANDS AND SPEECH QUERIES FOR LOCATING COMMANDS”, Scott A. Morgan et al. (U.S. application Ser. No. 09/213,858 filed Dec. 16, 1998, issued as U.S. Pat. No. 7,206,747); “SPEECH COMMAND INPUT RECOGNITION SYSTEM FOR INTERACTIVE COMPUTER DISPLAY WITH TERM WEIGHTING MEANS USED IN INTERPRETING POTENTIAL COMMANDS FROM RELEVANT SPEECH TERMS,” Scott A. Morgan et al. (U.S. application Ser. No. 09/213,845 filed Dec. 17, 1998, issued as U.S. Pat. No. 6,192,343); “SPEECH COMMAND INPUT RECOGNITION SYSTEM FOR INTERACTIVE COMPUTER DISPLAY WITH SPEECH CONTROLLED DISPLAY OF RECOGNIZED COMMANDS”, Scott A. Morgan (U.S. application Ser. No. 09/213,846 filed Dec. 17, 1998, issued as U.S. Pat. No. 6,937,984) and “METHOD AND APPARATUS FOR PRESENTING PROXIMAL FEEDBACK IN VOICE COMMAND SYSTEMS”, Alan R. Tannenbaum (U.S. application Ser. No. 09/213,857 filed Dec. 16, 1998, issued as U.S. Pat. No. 6,233,560).
TECHNICAL FIELD
The present invention relates to interactive computer controlled display systems with speech command input and more particularly to such systems which present display feedback to the interactive users.
BACKGROUND OF RELATED ART
The 1990's decade has been marked by a technological revolution driven by the convergence of the data processing industry with the consumer electronics industry. This advance has been even further accelerated by the extensive consumer and business involvement in the Internet over the past few years. As a result of these changes it seems as if virtually all aspects of human endeavor in the industrialized world require human/computer interfaces. There is a need to make computer directed activities accessible to people who up to a few years ago were computer illiterate or, at best, computer indifferent.
Thus, there is continuing demand for interfaces to computers and networks which improve the ease of use for the interactive user to access functions and data from the computer. With desktop-like interfaces including windows and icons, as well as three-dimensional virtual reality simulating interfaces, the computer industry has been working hard to fulfill such user interaction by making interfaces more user friendly by making the human/computer interfaces closer and closer to real world interfaces, e.g. human/human interfaces. In such an environment, it would be expected that speaking to the computer in natural language would be a very natural way of interfacing with the computer for even novice users. Despite these potential advantages of speech recognition computer interfaces, this technology has been relatively slow in gaining extensive user acceptance.
Speech recognition technology has been available for over twenty years, but it has only recently begun to find commercial acceptance, particularly with speech dictation or “speech to text” systems, such as those marketed by International Business Machines Corporation (IBM) and Dragon Systems. That aspect of the technology is now expected to have accelerated development until it will have a substantial niche in the word processing market. On the other hand, a more universal application of speech recognition input to computers, which is still behind expectations in user acceptance, is in command and control technology, wherein, for example, a user may navigate through a computer system's graphical user interface (GUI) by the user speaking the commands which are customarily found in the systems' menu text, icons, labels, buttons, etc.
Many of the deficiencies in speech recognition both in word processing and in command technologies are due to inherent voice recognition errors due in part to the status of the technology and in part to the variability of user speech patterns and the user's ability to remember the specific commands necessary to initiate actions. As a result, most current voice recognition systems provide some form of visual feedback which permits the user to confirm that the computer understands his speech utterances. In word processing, such visual feedback is inherent in this process, since the purpose of the process is to translate from the spoken to the visual. That may be one of the reasons that the word processing applications of speech recognition has progressed at a faster pace.
However, in speech recognition driven command and control systems, the constant need for switching back and forth from a natural speech input mode of operation, when the user is requesting help or making other queries, to the command mode of operation, when the user is issuing actual commands, tends to be very tiresome and impacts user productivity, particularly when there is an intermediate display feedback.
SUMMARY OF THE PRESENT INVENTION
The present invention and the cross-referenced copending applications are directed to provide solutions to the above-listed needs of speech recognition systems in providing command and control systems which are heuristic both on the part of the computer in that it learns and narrows from the natural speech to command user feedback cycles and on the part of the user, in that he tends to learn and narrow down to the computer system specific commands as a result of the feedback cycles. The present invention is directed to an interactive computer controlled display system with speech command input recognition which includes means for predetermining a plurality of speech commands for respectively initiating each of a corresponding plurality of system actions in combination with means for providing for each of said plurality of commands, an associated set of speech terms, each term having relevance to its associated command. Also included are means for detecting speech command and speech terms. Responsive to such detecting means, the system provides means responsive to a detected speech command for displaying said command, and means responsive to a detected speech term having relevance to one of said commands for displaying the relevant command.
The system further comprehends interactive means for selecting a displayed command to thereby initiate a system action; these selecting means are preferably speech command input means. The system can display the actual speech commands, i.e., commands actually spoken by the user simultaneously with the relevant commands i.e., commands not actually spoken but found in response to spoken terms having relevance to the commands.
The system of the present invention is particularly effective when used in the implementation of distinguishing actual spoken commands from spoken queries for help and other purposes, as covered in the above cross-referenced copending application Ser. No. 09/213,858.
In accordance with an aspect of the invention, the means for providing said associated set of speech terms comprise a stored relevance table of universal speech input commands and universal computer operation terms conventionally associated with actions initiated by said input commands, and means for relating the particular interactive interface commands of said system with terms in said relevance table.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood and its numerous objects and advantages will become more apparent to those skilled in the art by reference to the following drawings, in conjunction with the accompanying specification, in which:
FIG. 1 is a block diagram of a generalized data processing system including a central processing unit which provides the computer controlled interactive display system with voice input used in practicing the present invention;
FIG. 2 is a block diagram of a portion of the system of FIG. 1 showing a generalized expanded view of the system components involved in the implementation;
FIG. 3 is a diagrammatic view of a display screen on which an interactive dialog panel interface used for visual feedback when a speech command and/or speech term input has been made;
FIG. 4 is the display screen view of FIG. 3 after a speech term input has been made;
FIG. 5 is the display screen view of FIG. 4 after the user has finished inputting the speech term in FIG. 4 . (The user may then say one of the listed commands.);
FIG. 6 is a flowchart of the basic elements of the system and program in a computer controlled display system for creating and using the speech command recognition with visual feedback system of the present invention; and
FIG. 7 is a flowchart of the steps involved in running the program set up in FIG. 6 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 , a typical data processing system is shown which may function as the computer controlled display terminal used in implementing the system of the present invention by receiving and interpreting speech input and providing a displayed feedback, including some recognized actual commands, as well as a set of proposed relevant commands derived by comparing speech terms (other than commands) to a relevance table. A central processing unit (CPU) 10 , such as any PC microprocessor in a PC available from IBM or Dell Corp. is provided and interconnected to various other components by system bus 12 . An operating system 41 runs on CPU 10 , provides control and is used to coordinate the function of the various components of FIG. 1 . Operating system 41 may be one of the commercially available operating systems such as the OS/2™ operating system available from IBM (OS/2 is a trademark of IBM); Microsoft's Windows 95™ or Windows NT™, as well as the UNIX or AIX operating systems. A speech recognition program with visual feedback of proposed relevant commands, application 40 , to be subsequently described in detail, runs in conjunction with operating system 41 and provides output calls to the operating system 41 , which implements the various functions to be performed by the application 40 .
A read only memory (ROM) 16 is connected to CPU 10 via bus 12 and includes the basic input/output system (BIOS) that controls the basic computer functions. Random access memory (RAM) 14 , I/O adapter 18 and communications adapter 34 are also interconnected to system bus 12 . It should be noted that software components, including operating system 41 and application 40 , are loaded into RAM 14 , which is the computer system's main memory. I/O adapter 18 may be a small computer system interface (SCSI) adapter that communicates with the disk storage device 20 , i.e. a hard drive. Communications adapter 34 interconnects bus 12 with an outside network enabling the data processing system to communicate with other such systems over a local area network (LAN) or wide area network (WAN), which includes, of course, the Internet. I/O devices are also connected to system bus 12 via user interface adapter 22 and display adapter 36 . Keyboard 24 and mouse 26 are all interconnected to bus 12 through user interface adapter 22 . Audio output is provided by speaker 28 and the speech input which is made through input device 27 , which is diagrammatically depicted as a microphone which accesses the system through an appropriate interface adapter 22 . The speech input and recognition will be subsequently described in greater detail, particularly with respect to FIG. 2 . Display adapter 36 includes a frame buffer 39 , which is a storage device that holds a representation of each pixel on the display screen 38 . Images, such as speech input commands, relevant proposed commands, as well as speech input display feedback panels, may be stored in frame buffer 39 for display on monitor 38 through various components such as a digital to analog converter (not shown) and the like. By using the aforementioned I/O devices, a user is capable of inputting visual information to the system through the keyboard 24 or mouse 26 in addition to speech input through microphone 27 and receiving output information from the system via display 38 or speaker 28 .
Now with respect to FIG. 2 , we will describe the general system components involved in implementing the invention. Voice or speech input 50 is applied through microphone 51 which represents a speech input device. Since the art of speech terminology and speech command recognition is an old and well developed one, we will not go into the hardware and system details of a typical system which may be used to implement the present invention. It should be clear to those skilled in the art that the systems and hardware in any of the following patents may be used: U.S. Pat. No. 5,671,328; U.S. Pat. No. 5,133,111; U.S. Pat. No. 5,222,146; U.S. Pat. No. 5,664,061; U.S. Pat. No. 5,553,121; and U.S. Pat. No. 5,157,384. The speech input to the system could be actual spoken commands, which the system will recognize, and/or speech terminology, which the user addresses to the computer so that the computer may propose appropriate relevant commands through feedback. The input speech goes through a recognition process which seeks a comparison to a stored set of commands 52 . If an actual spoken command is clearly identified, spoken command 55 , that command may be carried out and then displayed via display adapter 36 to display 38 , or the spoken command may be displayed first and subsequently carried out. In this regard, the system is capable of several options, as will be subsequently described in greater detail. Suffice it to state that the present invention provides the capability of thus displaying actual commands.
Where the speech input contains terminology other than actual commands, the system provides for a relevance table 53 , which is usually a comprehensive set of terms which may be used in any connection to each of the actual stored commands 52 . If any of the input speech terms compare 54 with one of the actual commands, that actual command is characterized as a relevant command 56 which is then also presented to the user on display 38 via display adapter 36 . Although the relevance will be subsequently described in detail, it would be appropriate to indicate here how such a table is created. Initially, an active vocabulary is determined. This includes collecting from a computer operation, including the operating system and all significant application programs, all words and terms from menus, buttons and other user interface controls including the invisible but active words from currently active application windows, all names of macros supplied by the speech system, the application and the user, names of other applications that the user may switch to, generic commands that are generic to any application and any other words and terms which may be currently active. This basic active vocabulary is constructed into a relevance table wherein each word or term will be related to one or more of the actual commands and conversely, each of the actual commands will have associated with it a set of words and terms which are relevant to the command. It should be noted that this relevance table is dynamic in that it may be added to as appropriate to each particular computer operation. Let us assume that for a particular computer system there is a basic or generic relevance table of generic terminology, the active vocabulary for the particular system set is added to the basic relevance table and an expanded relevant vocabulary is dynamically created using at least some of the following expedients:
each word or phrase in the active vocabulary is added to the expanded vocabulary with an indication that it is an original active vocabulary word or phrase; each word or phrase in the active vocabulary is looked up as an index into the relevance table. If found, the corresponding contents of the cell in the table are used to further expand the vocabulary with any additional words or phrases that the cell may contain. These additional terms would have an associated reference to the active entry which caused its inclusion; each phrase is then broken into its constituent words, word pairs and n-word subphrases where applicable and the above process repeated; users may be encouraged to come up with there own lists of words and phrases which may be indexed with respect to the relevance table; and a synonym dictionary may be an additional source for words and phrases.
In the above description of display of commands both spoken and relevant with respect to FIG. 2 , we did not go into the display of the spoken input which could include commands and speech terms which would be compared to the relevance table for relevant commands. It will be understood that the spoken input will also be displayed separately. This will be seen with respect to FIGS. 3 through 5 which will provide an illustrative example of how the present invention may be used to give the visual feedback of displayed spoken commands, as well as relevant commands in accordance with the present invention. When the screen image panels are described, it will be understood that these may be rendered by storing image and text creation programs, such as those in any conventional window operating system in the RAM 14 of the system of FIG. 1 . The display screens of FIGS. 3 through 5 are presented to the viewer on display monitor 38 of FIG. 1 . In accordance with conventional techniques, the user may control the screen interactively through a conventional I/O device such as mouse 26 , FIG. 1 , and speech input is applied through microphone 27 . These operate through user interface 22 to call upon programs in RAM 14 cooperating with the operating system 41 to create the images in frame buffer 39 of display adapter 36 to control the display panels on monitor 38 . The initial display screen of FIG. 3 shows a display screen with visual feedback display panel 70 . In the panel, window 71 will show the words that the user speaks while window 72 will display all of the relevant commands, i.e. commands which were not actually spoken but some the spoken words or phrases in the window 71 were associated with the relevant commands through the relevance table, as shown in FIG. 2 . Also, any spoken commands which were part of the spoken input in window 71 will also be listed along with the relevant commands in window 72 . The panel also has command buttons: by pressing button 73 or saying the command, “Clear List”, the user will clear both window 71 and window 72 in FIG. 3 of all proposed relevant commands and input text. Pressing button 74 or saying the command, “Never mind”, causes the whole application to go away. FIG. 4 shows the screen panel 70 of FIG. 3 after the spoken entry, “Display the settings”. The system could find no actual command in this terminology but was able to find the four relevant commands shown in window 72 . Cursor icon 76 is adjacent the spoken term in window 71 as an indication that this field is the speech focus. In FIG. 5 we have the display of FIG. 4 , after the speech focus as indicated by cursor icon 76 has been moved to window 73 and the user has chosen one of the relevant commands: “Document Properties” 75 by speaking the command; as a result, the command is highlighted. Upon the relevant command being spoken, the system will carry it out.
Now with reference to FIGS. 6 and 7 we will describe a process implemented by the present invention in conjunction with the flowcharts of these figures. FIG. 6 is a flowchart showing the development of a process according to the present invention for providing visual feedback to spoken commands and other terminology, including a listing of system proposed relevant spoken commands which the user may choose from. First, step 80 , a set of recognizable spoken system and application commands which will drive the system being used is set up and stored. Then, there are set up appropriate processes to carry out the action called for by each recognized speech command, step 81 . A process for displaying recognized speech commands is also set up. In doing so, the program developer has the option among others of displaying all recognized commands or only recognized commands which are not clearly recognized so that the user will have the opportunity of confirming the command. Then, step 83 , there is set up a relevance table or table of relevant commands as previously described. This table hopefully includes substantially all descriptive phrases and terminology associated with the computer system and the actual commands to which each term is relevant. A process for looking up all spoken inputs, other than recognized commands, on this relevance table to then determine relevant commands is set up, step 84 . This involves combining the system and application commands with the relevance table to generate the vocabulary of speech terms which will be used by the speech recognition system to provide the list of relevant commands. This has been previously described with respect to FIG. 2 . Finally, there is set up a process for displaying relevant commands so that the user may choose a relevant command by speaking to set off the command action, step 85 . This has been previously described with respect to FIG. 5 . This completes the set up.
The running of the process will now be described with respect to FIG. 7 . First, step 90 , a determination is made as to whether there has been a speech input. If No, then the input is returned to step 90 where a spoken input is awaited. If the decision from step 90 is Yes, then a further determination is made in decision step 91 as to whether an command has been definitely recognized. At this point, we should again distinguish, as we have above, between spoken commands which the user apparently does not intend to be carried out as commands, i.e., they are just part of the input terminology or spoken query seeking relevant commands, and commands which in view of their presentation context are intended as definite commands. If a term in the context of a spoken query happens to match one of the commands, it is just listed with the relevant commands displayed as subsequently described with respect to step 97 . On the other hand, if a definite command is recognized, then the decision at step 91 would be Yes, and the command is carried out in the conventional manner, step 92 , and then a determination is made as to whether the session is at an end, step 93 . If Yes, the session is exited. If No, the flow is returned to step 90 where a further spoken input is awaited. If the decision from step 91 was No, that a definite command was not recognized, then a comparison is made on the relevance table as previously described, step 95 , and all relevant commands are displayed, step 97 , to give the user the opportunity to select one of the relevant commands. At decision step 98 , a determination is made as to whether the user has spoken one of the relevant commands. If Yes, then the process is returned to step 92 via branch “A” and the command is carried out. If the decision from step 98 is No, then a further decision is made, step 99 , as to whether the user has spoken any further terms. If Yes, the process is returned to step 95 where a comparison is made to the relevance table and the above process is repeated. If the decision from step 99 is No, then the process is returned to step 93 via branch “B” where a decision is made as to whether the session is over as previously described.
In this specification, the terms, relevant commands and actual commands may have been used in various descriptions. Both refer to real commands, i.e. commands which the particular system may execute. The distinction is based on whether the command is actually spoken. Thus an actual command would be one which the user actually speaks whether it be as part of the spoken entry or query which the user has uttered for the purpose of locating relevant commands or the actual command is one which the user intends to be executed in the conventional manner. On the other hand, a relevant command would be a command which was not spoken by the user but was associated with a word or term in the user's spoken entry through the relevance table.
One of the preferred implementations of the present invention is as an application program 40 made up of programming steps or instructions resident in RAM 14 , FIG. 1 , during computer operations. Until required by the computer system, the program instructions may be stored in another readable medium, e.g. in disk drive 20 , or in a removable memory such as an optical disk for use in a CD ROM computer input, or in a floppy disk for use in a floppy disk drive computer input. Further, the program instructions may be stored in the memory of another computer prior to use in the system of the present invention and transmitted over a LAN or a WAN, such as the Internet, when required by the user of the present invention. One skilled in the art should appreciate that the processes controlling the present invention are capable of being distributed in the form of computer readable media of a variety of forms.
Although certain preferred embodiments have been shown and described, it will be understood that many changes and modifications may be made therein without departing from the scope and intent of the appended claims. | In an interactive computer controlled display system with speech command input recognition and visual feedback, implementations are provided for predetermining a plurality of speech commands for respectively initiating each of a corresponding plurality of system actions in combination with implementations for providing for each of said plurality of commands, an associated set of speech terms, each term having relevance to its associated command. Also included are implementations for detecting speech command and speech terms. The system provides an implementation responsive to a detected speech command for displaying said command, and an implementation responsive to a detected speech term having relevance to one of said commands for displaying the relevant command. The system further comprehends an interactive implementation for selecting a displayed command to thereby initiate a system action; this selecting implementation is preferably through a speech command input. The system preferably displays the basic speech commands simultaneously along with the relevant commands. | 6 |
TECHNICAL FIELD OF THE INVENTION
The present invention is inserted in the field of study of the risk of calcic renal lithiasis, specifically on the development of a kit type system that allows the evaluation of the capacity of forming calcic crystals in a urine sample of any individual.
PRIOR ART OF THE INVENTION
The formation of renal calculus, as it is known, is due in practically all cases to the unfortunate combination of several factors. These factors may be classified in two large groups: I) factors inherent to the composition of urine. II) factors related to the morpho-anatomy of the kidney.
Urine is a metastable medium where there are normally different substances that may crystallize forming calculus (substances that are found in a state of supersaturation). Whether or not these substances crystallize depends on the degree of supersaturation, the presence of promoting substances (heterogeneous nucleants) and the presence of crystallization inhibitors.
The presence of cavities with a low urodynamic efficacy and that, therefore, keep the urine retained for long periods of time, and the alterations of the epithelium that covers the renal papilla (reduced or eliminated layer of glycosaminoglykanes, necrosis, . . . ) are factors linked to the renal structure that favor the formation of renal calculus.
Normally, the existence of factors belonging to both groups is necessary for the formation of renal calculus. The test that is presented precisely makes it possible to evaluate in a very simple manner the capacity that specific urine has to crystallize calcic salts, in such a way that the urine of a healthy individual would not give rise to growth of calcic salt crystals, while urine tending to form renal calculus (very supersaturated and/or with a significant inhibition deficit and/or abundant heterogeneous nucleants) would produce calcic salt crystals.
As bibliographic references closely related to the object of the present invention, the following may be cited: J. M. Baumann. How reliable are the measurements of crystallization conditions in urine? Urol. Res. 16, 133-135 (1988); J. M. Baumann. How to measure crystallization conditions in urine: A comparison of 7 methods. Report from a workshop held on Nov. 28, 1987 in Basle. Urol. Res 16, 137-142 (1988); F. Grases, O. Sohnel. Mechanism of oxalocalcic renal calculi generation, Int. Urol. Nephrol. 25, 209-214 (1993); F. Grases, A. Costa-Bauza, J. G. March, O. Sohnel, Artificial simulation of renal stone formation. Influence of some urinary components. Nephron 65, 77-81 (1993); F. Grases, A. Costa-Bauza, J. G. March. Artificial simulation of the early stages of renal stone formation. Brit. J. Urol. 74, 298-301 (1994).
ES-A-2088743 discloses a method for the determination of the inhibitive capacity of crystallization in human urine samples and the corresponding kit therefor.
The cited method essentially comprises the following operations:
(a) introducing the urine sample in a container that includes a substrate or flat solid surface that initiates crystallization, at 37° C. for about 5-6 hours; (b) removing the substrate containing the crystals and dissolving them in an acid medium; (c) evaluating the amount of calcium contained in said crystals.
The kit used to carry out this method comprises (1) a small vessel containing a substrate (2); (3) a container of the urine to be analyzed; (4) a container where the other container (1) is inserted; (5) a test tube type container, in which the dissolving of the crystals deposited in substrate (2) takes place.
Grases, F. et al (1995) International Urology and Nephrology 27: 653-661 discloses a similar process as that of ES-A-2088743.
Fernadndez-Dapica, M. P. et al. (1994) Arthritis & Rheumatism 370: s143 discloses a method for analyzing the calcium phosphate contents of synovial liquids using ARENAZO III colorimetrical assay. This method is inadequate for providing a simplified process for evaluating the capacity of urine as that of ES-A-2088743 inasmuch the method of Fernandez-Dapica implies digesting the samples of synovial fluid with NaOH at high temperatures (about 100° C.). U.S. Pat. No. 4,921,807 discloses a method and apparatus for maintaining urine specimens wherein thymol is added to the specimens for the purpose of preventing bacterial contamination/deterioration during storage and/or transport thereof.
The applicant has continued doing research on this method and kit, managing to improve both, so as to achieve a kit with easy industrial distribution and simplified use by the user in his home, as opposed to the need to carry out specialized laboratory tests.
DETAILED DESCRIPTION OF THE INVENTION
As indicated in the title, the present invention refers to a process of evaluation of the overall capacity of urine to form calcic renal stones and the corresponding kit therefor.
When an unprotected and unrenewed surface comes in contact with urine, sooner or later those substances that are supersaturated and whose inhibition is deficient end up crystallizing on it. The ease with which this crystallization takes place depends on how favorable the combination of factors that stimulate it is. Thus, by using a suitable surface it is possible to calculate a time period for which urine with a normal composition does not crystallize, while lithogenous urine gives rise to the growth of calcic salts on the same. Detection of the calcium produced in these conditions is carried out by using a calorimetric reaction. In short, there are two reactions that take part in the process: a precipitation reaction and a complexation reaction.
Precipitation reaction: Ca 2+ Oxalate/Phosphate >Oxalate/Calcium phosphate
Complexation reaction: Redissolved Ca (II)+2,7-Naphthalenedisulfonic acid, 3,6-bis((2-arsonophenyl)azo)-4,5-dihydroxy (ARSENAZO III). →Blue complex
pH=4.3
In order to carry out the process of the present invention, a kit that is represented in FIG. 1 and that essentially comprises a vessel containing thymol as a sterilizing agent (1), within which there is a reaction cup (2), where the reaction substrate (3) is located, has been designed.
In order to carry out the test the following reagents (prepared in bidistilled water with reagents of maximum purity) are needed.
Reaction units
Aqueous solution of 2.3 N hydrochloric acid
Aqueous solution of anhydrous sodium acetate 5% (w/v)
Aqueous solution of ARSENAZO III, 0.1% (w/v)
All of the solutions must be kept between 2 and 8° C. They must be brought to room temperature (20 to 30° C.) 30 minutes before they are used. The hydrochloric acid and ARSENAZO III solutions are stable for the 90 days following their preparation when they are kept between 2 and 8° C. The sodium acetate solution is stable for 30 days when it is kept between 2 and 8° C.
The reaction units must be kept closed and at room temperature (20 to 30° C.).
The collecting of the sample will be done in a sterile 100 mL bottle. The urine must be discharged before breakfast, if possible the first urination in the morning and if not the following urination but always before breakfast.
Neither additives nor preservatives should be added to the collected sample.
It is essential that the test is started with recently discharged and even warm urine in order to prevent precipitation reactions from being produced due to cooling of the urine. Cooled or frozen samples must never be used.
The analytic process of the invention involves a series of steps that are outlined in FIG. 2 and that are specified in detail hereinafter.
1. --Label the reaction unit with the patient's identification.
2. --Pour 40 mL of recently discharged urine on the plate. Make sure that the reaction cup is filled with urine. Cover the container plate.
3. --Allow the sample to rest for:
a) 6 h at 37° C. or 12 h at room temperature (20 to 30° C.)
b) 24 h at room temperature (20 to 30° C.)
4. --Discard the contents of the containing plate.
5. --Carefully wash the plate with 50 mL of bidistilled water. Do not pour the water directly on the reaction cup. Stir for 5 seconds with gentle stirring movement. Discard the water.
6. --Add 400 μL of the acid solution to the reaction cup.
7. --Spread the solution over the entire surface by means of gentle but continuous movement with a plastic spatula. Prolong this operation for about 2 minutes.
8. --Add 2.8 mL of the acetate solution to the reaction cup.
9. --Add 150 μL of the ARSENAZO III solution to the reaction cup.
10. --Mix with the spatula while the reaction is being completed (about 15 sec.)
11. --Interpret the result qualitatively and/or quantitatively.
It is recommended that a negative control be prepared daily as a contrast in order to verify the test result. The negative control is prepared on the cup of one new reaction unit to which the previous protocol as of step 6 will be applied.
Once the test has ended, a stained solution is obtained. In terms of the color the result is evaluated qualitatively as positive or negative.
Negative non-lithogenous urine will have a pink color similar to that of the negative control.
Positive lithogenous urine will have a blue color, whose shade may vary from violet to blue.
Urine with a lithogenous risk close to cut-off, that is to say, to the sensibility limit of the test, will have a pink color with a slight bluish tone.
In those cases in which it is considered convenient, clinical laboratory analysis may proceed a quantitative interpretation of the obtained results. In order to do so, it suffices to determine the absorbency of the stained solution at 650 nm in comparison to a target of bidistilled water using dishes of 1 cm of optical path. In this case the result will be expressed in the concentration of calcium (μg/mL) and will be calculated in accordance with the following equation:
[Calcium].sub.m =A.sub.m x [Calcium].sub.std /A.sub.std
wherein: [Calcium] m is the concentration of calcium of the sample.
A m is the absorbency of the sample.
[Calcium] std is the concentration of calcium of a standard solution.
A std is the absorbency of a standard solution.
The concentration of calcium in the stained solution may also be directly determined by means of atomic absorption spectrometry (AAS) or inductively coupled plasma-atomic emission spectrometry (ICP-AES).
For non-lithogenous urine the concentration of calcium in the stained solution will be between 0 and 2 μg/mL.
For lithogenous urine the concentration of calcium in the stained solution will be between 3 and 30 μg/mL. Crystallizations above 30 μg/mL have rarely been obtained.
For urine with a lithogenous risk close to cut-off, that is to say, the sensitivity limit of the test, the concentration of calcium in the stained solution will be between 2 and 3 μg/mL.
The results obtained by applying the test show an excellent discrimination between the group of healthy individuals and the group of patients with a significant lithiasic activity and altered urine, which shows the usefulness of the test to evidence the existence of urinary disorders that may lead to the formation of renal calculus. It is obvious that if one wishes to specifically detect a specific disorder, it will be necessary to carry out a more detailed urinalysis.
It is important to point out that it may happen that clearly lithogenous urine may belong to an individual who has never formed renal calculus, due to the fact that the morpho-anatomic factors of the kidney are especially oriented towards avoiding the formation of solid concretions, for example, as a result of the existence of a particularly well developed layer of glycosaminoglykanes (nonsticking layer). The contrary may also happen, wherein, totally normal urine from a lithogenous point of view, belongs to a clearly lithiasic individual, which must be attributed to a situation wherein the morpho-anatomic factors of the kidney are clearly altered, for example, by the presence of significant papillary necrosis, that would favor the formation renal calculus. It must also considered that the lithogenous activity of an individual is not the same every day of the year. There are seasons, such as the summer for example, especially suited to the formation of renal calculus, and the influence of cycles, such as the menstrual cycle which affects the elimination of citrate, must also be considered. Therefore, it is obvious that for a lithiasic individual there may be periods when his urine has no lithiasic activity and others when it has lithiasic activity. The application of the test will undoubtedly allow the detection of said periods.
In short, the proposed test makes it possible to carry out an overall evaluation of the urinary risk to form calcic calculus. If the result is positive, it will indicate a clear predisposition of the urine to form calcic calculus, in such a way that if one wishes to know more exactly the altered urinary factor(s) (hypercalcuria, hypocyturia . . . ) it will be necessary to carry out a more complete urinalysis. If the result of the test is negative and calcic calculus are formed in the absence of urinary infection, it is a clear indication that the alteration that produces them basically arises from the morpho-anatomic factors of the kidney.
Therefore, the application of the test will be of special interest for:
1) Rapid sampling of patients with calcic lithiasis for the purpose of detecting those individuals who have altered urine and that must be subjected to a more complete urinalysis.
2) Identification of the predisposition of the formation of calcic renal calculus in individuals with an important lithogenous risk factor (for example, in cases of the existence of direct family case histories.)
3) Evaluation of the efficacy of a specific corrective therapy of the urinary lithogenous risk.
4) Detection of periods of marked lithogenous activity.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 represents the kit of the present invention, wherein (1) corresponds to the container containing thymol, (2) corresponds to the cup and (3) corresponds to the reaction substrate.
FIG. 2 represents an illustrative diagram of the test method of the present invention.
EMBODIMENTS OF THE INVENTION
The present invention is additionally illustrated by means of the following Examples which are not restrictive of the scope hereof.
EXAMPLE 1
40 mL of recently discharged urine were taken and deposited in a container plate making sure that the cup was filled. It was covered and allowed to rest for 6 hours at 37° C.
Once this time has gone by, the plate was carefully washed with 50 mL of bidistilled water with the precaution of not pouring it directly on the reaction cup, it was stirred gently for 5 seconds and the water was discarded.
Then 400 μL of an aqueous solution of 2,3N hydrochloric acid were added and extended carefully with a plastic spatula for 2 minutes. Afterwards, 2.8 mL of an aqueous solution of anhydrous sodium acetate 5% (w/v) and 150 μL of ARSENAZO III were added. It was mixed with the spatula for 15 seconds and then the formation of the pink color was observed, indicating an non-lithogenous urine.
EXAMPLE 2
The process described in Example 1 was repeated, using recently discharged urine from another subject. The urine was kept in contact with the substrate for 12 hours at room temperature.
The stain at the end of all the stages of the process was blue, indicating a lithogenous urine. | A process is provided for evaluating the global capacity of urine to form chalky renal calculus, the process comprising the steps of pouring a sample of a recently discharged urine into a container plate bearing, on its inner bottom portion, a cup containing a reaction substrate capable of initiating crystallization of calcium in the sample, allowing the sample to rest; discarding the sample from the container plate, washing the container plate with bidistilled water and discarding the water, adding a diluted HCl solution (2.3N) and spreading it over the entire surface of the substrate contained in the cup, adding an aqueous sodium acetate solution (5% w/v) and an indicating solution of ARSENAZO III (0.1% w/v) and mixing the acetate solution and the indicating solution for 15 seconds, to obtain a stained reaction mixture which can be qualitatively and quantitatively evaluated. A kit for carrying out this process is also provided. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2006-51526, filed Feb. 28, 2006, the entire contents of which are incorporated herein by reference.
BACKGROUND
1. Field
Embodiments of the present invention relate to a power-saving technology for notebook computers, and in particular to an information processing apparatus and a control method by which supply of power source to respective operating equipment can be controlled in accordance with a state of opening and closing of a display.
2. Description of the Related Art
Previously, there has been a technology in which, in a notebook personal computer, an internal power supply, an external power supply, and a system power supply are switched On/OFF based on the detected angle between a main body unit of the computer and its rotational display unit.
In the technology described above, however, it is sometimes difficult or impossible to operate various switches and devices when the angle between the display unit and the main body unit is below a predetermined angle. Thus, when the display unit is in various angular positions, power is consumed needlessly.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is an exemplary perspective view showing a notebook computer which is an information processing apparatus according to a first embodiment of the invention;
FIG. 2 is an exemplary block diagram showing a configuration of the notebook computer which is the information processing apparatus according to the first embodiment of the invention;
FIG. 3 is an exemplary flowchart for explanation of a method of controlling the information processing apparatus according to the first embodiment of the invention;
FIG. 4 is an exemplary schematic view showing an angle of a panel with a main body;
FIG. 5 is an exemplary schematic view showing setting areas of various switches and devices which are arranged at the main body and the panel of the computer according to the first embodiment of the invention;
FIG. 6 is an exemplary flowchart for explanation of a method of controlling an information processing apparatus according to a second embodiment of the invention;
FIG. 7 is an exemplary perspective view showing a notebook tablet PC which is the information processing apparatus according to the second embodiment of the invention; and
FIG. 8 is an exemplary perspective view showing a tablet style of the notebook tablet PC which is the information processing apparatus according to the second embodiment of the invention.
DETAILED DESCRIPTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First Embodiment
FIG. 1 is a perspective view of an information processing apparatus according to a first embodiment of the present invention. The information processing apparatus is realized as a notebook computer 10 which can be driven by a battery.
As shown in FIG. 1 , the computer 10 is configured of a main body 16 and a display 11 . A display device composed of a liquid crystal display (LAD) is built into the display 11 , and a display screen 12 of the LAD is positioned in substantially the center of the display 11 .
The display 11 is attached to main body 16 so as to be freely opened and closed between a release position and a lock up position with respect to the computer 10 . The main body side of the computer 10 has a thin box type housing. A plurality of input devices are positioned on a top surface of the main body 16 . For instance, a keyboard 13 is arranged on a top surface of the housing, and a touch pad 14 , left and right two buttons 14 a and 14 b , and various short cut buttons 18 such as mail and the like are arranged on a palm rest. Further, an optical drive 15 and the like are provided at the side faces of the main body 16 . Moreover, a fingerprint authentication device 17 is arranged at a lower portion of the display 11 .
FIG. 2 is a block diagram showing a configuration of the computer.
The computer 10 includes a central processing unit (CPU) 20 , a Root Complex 21 , a main memory 24 , a graphics controller (End Point) 23 , a PHI Express Link 22 which connects the Root Complex 21 and the graphics controller 23 , the display 11 , an embedded controller/keyboard controller IC (EBC/KBC) 27 , a hard disk drive (HDD) 25 , a BIOS-ROM 26 , and the fingerprint authentication device 17 , the keyboard 13 , the touch pad 14 , and various shortcut buttons 18 which are input devices connected to the EBC/KBC 27 , and an angle detection device 19 which detects an angle between the main body 16 and the display 11 .
The Root Complex 21 , the graphics controller 23 , and the like are devices compliant with the PHI EXPRESS standard. Communication between the Root Complex 21 and the graphics controller 23 is achieved via the PHI® EXPRESS® Link 22 arranged between the Root Complex 21 and the graphics controller 23 .
The CPU 20 is a processor which controls operations of the main computer 10 , and executes various programs (an operating system, application programs) loaded in the main memory 24 from the HDD 25 . Further, the CPU 20 also executes a basic input output system (BIOS) stored in the BIOS-ROM 26 . The BIOS is a program for controlling hardware.
The Root Complex 21 is a bridge device which makes a connection between a local bus of the CPU 20 and the graphics controller 23 . Further, the Root Complex 21 also has a function of controlling communications with the graphics controller 23 via the PHI® EXPRESS® Link 22 .
The graphics controller 23 is a display controller which controls the display 11 used as a display monitor of the main computer.
The EBC/KBC 27 is a one-chip microcomputer in which an embedded controller for managing power and a keyboard controller for controlling the keyboard 13 , the touch pad 14 and the like are integrated. The EBC/KBC 27 has a function of turning power-ON/OFF of the main computer 10 in cooperation with a power supply controller depending on an operation of a power button by a user.
Next, a method of controlling an information processing apparatus according to the first embodiment of the invention will be described with reference to a flowchart of FIG. 3 .
Note that, in the present embodiment, an operation of closing the panel from a state in which the display (hereinafter called a panel) 11 is opened will be described with reference to the flowchart of FIG. 3 .
The CPU 20 of the computer 10 determines whether or not an angle of the panel 11 forms, for example, 10° with the main body 16 on the basis of information from the angle detection device 19 (block S 101 : refer to FIG. 4 ). When the CPU 20 determines in block S 101 that the angle of the panel 11 forms 10° with the main body 16 (YES in block S 101 ), it is determined whether or not the angle of the panel 11 forms 5° with the main body 16 (block S 102 ). When the CPU 20 determines that the angle of the panel 11 does not form 5° with the main body 16 (NO in block S 102 ), supply of power source to the fingerprint authentication device 17 , the various shortcut buttons 18 , and some of the upper portion of the keyboard 13 which are arranged in the areas of areas A 1 and A 2 shown in FIG. 5 is switched off (block S 103 ). Note that, when supply of power source to these devices is switched off, a plurality of switch units may be provided in one power supply circuit, or a plurality of power supply circuits may be provided.
In summary, according to one embodiment of the invention, the input devices are powered down in a predetermined order based on their proximity to the hinge rotationally coupling display device 11 to main body 16 of FIG. 1 . Hence, input devices in areas A 1 & A 2 of FIG. 5 become inaccessible sooner than input devices in areas B 1 & B 2 of FIG. 5 as display unit 11 is rotated toward main body 16 .
On the other hand, when the CPU 20 determines that the angle of the panel 11 forms 5° with the main body 16 (YES in block S 102 ), supply of power source to the LAD 12 , the keyboard 13 , and the touch pad 14 which are arranged in the areas of areas B 1 and B 2 shown in FIG. 5 is switched off (block S 104 ).
Note that setting of areas in which supply of power source is switched off is not limited to the content described above, and can be set in various ways. Further, when devices whose operations are limited in accordance with an angle between the panel 11 and the main body 16 are mounted in addition to the devices such as the touch pad 14 shown in the present embodiment, the effect of the present invention can be enjoyed by applying the present invention to those devices in the same way.
Next, an operation of opening the panel from a state in which the panel 11 is closed will be described with reference to a flowchart of FIG. 6 .
The CPU 20 of the computer 10 determines whether or not an angle of the panel 11 forms, for example, 5° with the main body 16 on the basis of information from the angle detection device 19 (block S 111 : refer to FIG. 4 ). When the CPU 20 determined in block S 111 that the angle of the panel 11 forms 5° with the main body 16 (YES in block S 111 ), supply of power source to the LAD 12 , the keyboard 13 , and the touch pad 14 which are arranged in the areas of the areas B 1 and B 2 shown in FIG. 5 is switched on (block S 112 ).
Moreover, the CPU 20 determines whether or not the angle of the panel 11 forms 10° with the main body 16 (block S 113 ). When the CPU 20 determines that the angle of the panel 11 forms 10° with the main body 16 (YES in block S 113 ), supply of power source to the fingerprint authentication device 17 , the various shortcut buttons 18 , and some of the upper portion of the keyboard 13 which are arranged in the areas of the areas A 1 and A 2 shown in FIG. 5 is switched on (block S 114 ).
In accordance with the above embodiment, it is possible to switch off supply of power source to the various switches and the devices which are made impossible to operate due to the various switches and the devices provided to the main body unit being hidden, stepwise in accordance with an angle of the display unit. On the other hand, it is possible to switch on supply of power source to the various switches and the devices stepwise when the various switches and the devices provided to the main body unit are made possible to operate.
Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIGS. 7 and 8 .
FIG. 7 is a perspective view showing a notebook tablet PC serving as an information processing apparatus according to the second embodiment of the invention.
A tablet PC 100 is configured by: a main body 160 having a keyboard 130 , a touch pad 140 , a hinge portion 60 serving as a connection portion with a liquid-crystal system movable display 120 , and the like; and the display 120 connected so as to be movable to the hinge portion 60 having various buttons 180 . In the tablet PC 100 , the display 120 is made to be a touch panel, and it is possible to directly carry out operations with respect to the display 120 by a stylize 80 or the like.
The display 120 is rotatable centering around Y-axis on the hinge portion 60 . Further, the display 120 can be reclined centering around X-axis. For example, when the display 120 is reclined with the display surface thereof up, the tablet PC 100 is made to be a tablet style as shown in FIG. 8 . In a case of using the tablet style in this way, for example, a pattern is acceptable in which two users utilize it while looking at the display 120 .
Also when the tablet PC 100 is used, setting can be made such that the areas A 1 , A 2 , B 1 , and B 2 described in the first embodiment, or the like are provided, and supply of power source is switched on/off depending on an angle between the display 120 and the main body 160 every area. Consequently, the same effect as that of the first embodiment described above can be achieved.
In the same way, when devices whose operations are limited in accordance with an angle between the display 120 and the main body are mounted in addition to the devices shown in the embodiment, the effect of the present invention can be achieved by applying the invention to those devices in the same way.
Further, the invention is not limited to the above-described embodiments, and at the stage of implementing the invention, the invention can be embodied by modifying components within a range without departing from the gist of the present invention. Further, various inventions can be made by appropriate combinations of a plurality of components disclosed in the above-described embodiments. For example, some components may be eliminated from all the components shown in the embodiments. Moreover, the components over the different embodiments may be appropriately combined. | According to one embodiment, an information processing apparatus includes a display device, a main body rotatably connected to the display device and overlapping so as to at least partly face the display device, and a plurality of input devices either on the main body or the display device and covered with the display device when the display device is overlapped. When the display device rotates in a direction of overlapping onto the main body, supply of power source to the operating means is switched off stepwise in an order set in advance, in accordance with an angle between the display device and the main body. | 8 |
This is a divisional of U.S. application Ser. No. 07/985,395, filed Dec. 4, 1992, now U.S. Pat. No. 5,322,950, which is a continuation-in-part of U.S. application Ser. No. 07/802,652, filed Dec. 5, 1991, now abandoned.
BACKGROUND OF THE INVENTION
The instant invention relates to novel imidazole and 1,2,4-triazole derivatives which antagonize the binding of angiotensin II (AII) to cellular receptors. This AII antagonist property renders these compounds useful for treatment of angiotensin-related hypertension.
The enzyme renin acts on a blood plasma α 2 -globulin, angiotensinogen, to produce angiotensin I, which is then converted by angiotensin-converting enzyme to AII. The latter substance is a powerful vasopressor agent which has been implicated as a causative agent for producing high blood pressure in various mammals, such as rats, dogs, and humans. The compounds of this invention inhibit the action of AII at its receptors on target cells and thus prevent the increase in blood pressure produced by this hormone-receptor interaction. By administering a compound of the instant invention to a species of mammal with hypertension due to AII, the blood pressure is reduced. The compounds of the invention are also useful for the treatment of congestive heart failure, hyperaldosteronism and glaucoma.
European Application Number 253,310 (U.S. Pat. No. 5,138,069) discloses imidazoles of the formula ##STR1##
The compounds are disclosed as having utility in treating hypertension and congestive heart failure.
European Application Number 323,841 discloses substituted pyrrole-, pyrazole-, and triazole-containing compounds of the formulas ##STR2##
European Application Number 324,37 (U.S. Pat. Nos. 5,128,355 and 5,138,069) discloses a pharmaceutical composition of a diuretic or a nonsteroidal antiinflammatory drug useful for blocking the angiotensin II receptor.
U.S. Pat. No. 4,355,040 discloses imidazole-5-acetic acid derivatives of the formula ##STR3## wherein R 1 is lower alkyl, cycloalkyl or, phenyl which may be substituted with one to three of halogen, nitro, amino, mono(lower alkyl)amino, di(lower alkyl)amino, lower alkyl, lower alkoxyl, benzyloxyl or/and hydroxyl; X 1 , X 2 , and X 3 are each hydrogen, halogen, nitro, amino, lower alkyl, lower alkoxyl, benzyloxyl or hydroxyl; Y is halogen and R 2 is hydrogen or lower alkyl; provided that X 1 is halogen, lower alkyl, lower alkoxyl, benzyloxyl or hydroxyl when R 1 is unsubstituted or substituted phenyl only with one halogen, di(lower alkyl)amino, lower alkyl or lower alkoxyl, and its salts. The compounds are disclosed as having antihypertensive activity.
European Applications Numbers 403158 and 403159 disclose angiotensin II receptor antagonists of formula ##STR4## wherein R 1 is phenyl, biphenyl, naphthyl, or adamantylmethyl, which are unsubstituted or substituted by one to three substituents selected from Cl, Br, F, I, C 1 -C 4 -alkyl nitro CO 2 R 7 tetrazol-5-yl C 1 -C 4 -alkoxy, hydroxy, SC 1 -C 4 alkyl, SO 2 NHR 7 , SO 3 H, CONR 7 R 7 , CN, SO 2 C 1 -C 4 alkyl or C n F 2n1 , wherein n is 1 to3;
R 2 is C 2 -C 10 alkyl, C 3 -C 10 alkenyl, C 3 -C 10 alkynyl, C 3 -C 6 cycloalkyl, , or (CH 2 ) 0-3 phenyl unsubstituted or substituted by one to three substituents selected from C 1 -C 4 alkyl, nitro, Cl, Br, F, I, hydroxy, C 1 -C 4 alkoxy, or NR 7 R 7 ;
X is a single bond, S, or O:
R 3 is hydrogen, Cl, Br, F, I, CHO, hydroxymethyl, COOR 7 , CONR 7 R 7 , NO 2 , or C n F 2n1 , wherein n is 1 to 3;
R 4 and R 5 are independently hydrogen, C 1 -C 5 alkyl, phenyl--Y--, naphthyl--Y--, or biphenyl--Y--, wherein the aryl groups are unsubstituted or substituted by one to three substituents selected from Cl, Br, F, I, C 1 -C 4 alkoxy, hydroxy, CO 2 R 7 , CN, NO 2 , tetrazol-5-yl, SO 3 H, CF 3 , CONR 7 R 7 , SO 2 NHR 7 , C 1 -C 4 -alkyl, or NR 7 R 7 , or by methylenedioxy, phenoxy, or phenyl, except that R 4 and R 5 are not both selected from hydrogen or C 1 -C 6 alkyl;
Y is a single bond, O, S, or C 1 -C 6 alkyl which is straight or branched or optionally substituted by phenyl or benzyl, wherein each of the aryl groups is unsubstituted or substituted by halo, NO 2 , CF 3 , C 1 -C 4 alkyl, C 1 -C 4 alkoxy, CN, or CO 2 R 7 ;
R 6 is --Z--COOR 6 or --Z--CONR 7 R 7 ;
Z is a single bond, vinyl, CH 2 --O--CH 2 --, methylene optionally substituted by C 1 -C 4 alkyl, one or two benzyl groups, thienylmethyl, or furylmethyl, or --C(O)NHCHR 9 --, wherein R 9 is H, C 1 -C 4 alkyl, phenyl, benzyl, thienylmethyl, or furylmethyl;
each R 7 independently is hydrogen, C 1 -C 4 alkyl, or (CH 2 ) m phenyl, wherein m is 0 to 4; and
R 6 is hydrogen, C 1 -C 6 alkyl, or 2-di(C 1 -C 4 alkyl)amino-2-oxoethyl; or
R 5 and R 6 are both hydrogen, R 4 is and --Z--COOR 8 and Z is other than a single bond; or a pharmaceutically acceptable salt thereof.
Copending U.S. application Ser. No. 07/757021 covers novel anilide derivatives which antagonize the binding of angiotensin II to its receptors. The compounds are those of formula ##STR5##
SUMMARY
The instant invention concerns a compound of formula ##STR6## or the pharmaceutically acceptable acid addition or basic salts thereof wherein X, B, R, R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are as defined below.
Angiotensin II mediates a variety of responses in various tissues, including contraction of vascular smooth muscle, excretions of salt and water from kidney, release of prolactin from pituitary, stimulation of aldosterone secretion from adrenal gland, and possible regulation of cell growth in both cardiac and vascular tissue. As antagonists of angiotensin II, the compounds of Formula I are useful in controlling hypertension, hyperaldosteronism, and congestive heart failure in mammals. Additionally, antihypertensive agents as a class have been shown to be useful in lowering intraocular pressure. Thus, the compounds of Formula I are also useful in controlling glaucoma..
The invention also includes a pharmaceutical composition comprising an antihypertensive effective amount of a compound of Formula I above in admixture with a pharmaceutically acceptable carrier or excipient and a method for treating hypertension in a mammal suffering therefrom which comprises administering to said mammal the above pharmaceutical composition in unit dosage form.
Further, the invention includes a pharmaceutical composition comprising an amount of a compound of Formula I above effective for treating hyperaldosteronism in admixture with a pharmaceutically acceptable carrier or excipient, and a method for treating hyperaldosteronism in a mammal suffering therefrom comprising administering to said patient the above pharmaceutical composition in unit dosage form.
Also, the invention includes a pharmaceutical composition comprising an amount effective for treating congestive heart failure of a compound of Formula I above in admixture with a pharmaceutically acceptable carrier or excipient and a method of treating congestive heart failure in a patient suffering therefrom comprising administering to said patient the above pharmaceutical composition in unit dosage form.
Also the invention includes a pharmaceutical composition comprising an amount of a compound of Formula I above effective for treating glaucoma in admixture with a pharmaceutically acceptable carrier or excipient; and a method of treating glaucoma in a patient suffering therefrom comprising administering to said patient the above pharmaceutical composition in unit dosage form.
The instant invention further includes methods for making compounds of Formula I.
DETAILED DESCRIPTION
The compounds of the present invention are represented by the formula ##STR7## or a pharmaceutically acceptable salt thereof wherein R 1 is adamantylmethyl,
phenyl,
biphenyl, or
naphthyl, each of which is unsubstituted or substituted by one to three substituents selected from
Cl,
Br,
F,
I,
alkyl of from one to four carbon atoms,
nitro,
tetrazol-5-yl,
alkoxy of from one to four carbon atoms,
hydroxy,
SO 3 H,
SO 2 alkyl of from one to four carbon atoms,
CN,
C n F 2n+1 wherein n is an integer of from 1 to 3,
CO 2 R 4 ,
SO 2 NHR 4 ,
NHSO 2 R 4 ,
NHSO 2 C n F 2n+1 ,
CON(R 4 ) 2 wherein R 4 is hydrogen or lower alkyl;
X is a single bond, S, or O;
R 2 is alkyl of from two to ten carbon atoms, alkenyl of from two to ten carbon atoms, alkynyl of from three to ten carbon atoms, cycloalkyl of from three to six carbon atoms,
(CH 2 ) m phenyl wherein m is an integer of from zero to eight and phenyl is unsubstituted or substituted by one to three substituents selected from alkyl of from one to four carbon atoms,
nitro,
Cl,
Br,
F,
I,
hydroxy,
alkoxy of from one to four carbon atoms, or NR 4 R 4 wherein R 4 is as defined above;
R 3 is hydrogen,
Cl,
Br,
F,
I,
CHO,
hydroxymethyl,
alkyl,
aryl,
heteroaryl,
CO 2 R 4 ,
CONR 4 R 4 ,
NO 2 , or
C n F 2n+1 wherein n is as defined above;
R 4 is hydrogen or alkyl of from one to five carbon atoms,
R is hydrogen or alkyl of from one to five carbon atoms which alkyl is unsubstituted or substituted with
CN,
CO 2 R 4 ,
tetrazol-5-yl,
CONHR 4 ,
CONH(CH 2 ) n CO 2 R 4
phenyl unsubstituted or substituted by one to three substituents selected from
alkyl of from one to four carbon atoms,
nitro,
Cl,
F,
I,
hydroxy,
alkoxy of from one to four carbon atoms, or NR 4 R 4 wherein R 4 is as defined above;
Additionally, R is
OR 4 ,
O(CH 2 ) n CO 2 R 4 .
R 5 and R 6 are each independently
hydrogen,
halogen,
alkyl of from one to five carbon atoms,
alkyloxy of from one to five carbon atoms,
NO 2 ,
NHCOR 4 ,
NHSO 2 R 4 ,
(CH 2 ) n CO 2 R 7 wherein n and R 4 are as defined above; and
B is a bond, or CO; and
the indicates a double or single bond.
More preferred compounds of the invention are those of Formula I wherein
R 1 is phenyl
biphenyl, or
naphthyl, each of which is unsubstituted or substituted by one to three substituents selected from
Cl,
F,
alkyl of from one to four carbon atoms,
nitro,
tetrazol-5-yl,
alkoxy of from one to four carbon atoms,
hydroxy,
SO 3 H,
CN,
C n F 2n+1 wherein n is an integer of from 1 to 3,
CO 2 R 4 ,
SO 2 NHR 4 ,
NHSO 2 R 4 ,
CONR 4 R 4 wherein R 4 is hydrogen or lower alkyl;
X is a single bond or S;
R 2 is alkyl of from two to eight carbon atoms, or cycloalkyl of from three to six carbon atoms,
R 3 is hydrogen,
Cl,
F,
I,
CHO,
hydroxymethyl,
alkyl,
aryl,
pyrrole,
CO 2 R 4 ,
CONR 4 R 4 ,
NO 2 , or
C n F 2n+1 wherein n is as defined above;
R 4 is hydrogen or alkyl of from one to four carbon atoms,
R is hydrogen or alkyl of from one to four carbon atoms unsubstituted or substituted with
CO 2 R 4 ,
tetrazol-5-yl,
CONHR 4 wherein R 4 is as defined above;
R 5 and R 6 are each independently
hydrogen,
alkyl of from one to four carbon atoms,
alkyloxy of from one to four carbon atoms,
NO 2 ,
NHCOR 4 ,
NHSO 2 R 4 ,
(CH 2 ) n CO 2 R 4 wherein n, R 4 , is as defined above; and
B is a bond, or CO.
The indicates a double bond
Still more preferred compounds of the invention are those of Formula I wherein
R 1 is phenyl substituted by one to three substituents selected from
Cl,
F,
trifluoromethyl,
nitro,
methyl,
methoxy,
hydroxy,
sulfonamido,
carboxy,
carboC 1 -C 4 alkoxy,
carbamoyl,
CN, or
tetrazol-5-yl;
X is a single bond;
R 2 is alkyl of from two to eight carbon atoms;
R 3 is hydrogen,
R 4 is hydrogen,
R is CH 2 CO 2 R 4 wherein R 4 is hydrogen or lower alkyl;
R 5 is alkyl of from one to four carbon atoms;
R 6 is hydrogen; and
B is a bond.
The indicates a double bond.
Most especially preferred compounds of the invention are:
Ethyl 4-[[2-butyl-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Methyl 4-[[2-butyl-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H -imidazol-1-yl]methyl]-3-chlorobenzoate;
Methyl 4-[[2-butyl-5-[(1,2-dihydro-5-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Ethyl 4-[[2-butyl-4-chloro-5-[(1,2-dihydro-6-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Methyl 4-[[2-propyl-5-[(1,2-dihydro-1-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Methyl 4-[[2-butyl-5-[(1,2-dihydro-4-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Methyl 4-[[2-butyl-5-[(1,2-dihydro-7-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Methyl 4-[[2-butyl-5-[(5-chloro-1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1yl]methyl]benzoate;
Methyl 4-[[2-butyl-5-[(1,2-dihydro-7-methoxy-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Ethyl 3-[[2-butyl-1-[[4-(methoxycarbonyl)phenyl]methyl]-1H -imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-5-carboxylate;
Ethyl 4-[[2-butyl-4-chloro-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Ethyl 3-[[2-butyl-1-[[(4-methoxycarbonyl)phenyl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetate;
(E)-4-[[2-butyl-4-chloro-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoic acid;
4-[[2-butyl-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene) methyl]-1H-imidazol-1-yl]methyl]benzoic acid;
4-[[2-butyl-5-[(1,2-dihydro-7-methoxy -2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoic acid;
3-[[2-butyl-1-[(4-carboxyphenyl)methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid;
3-[[2-butyl-1-[(4-carboxyphenyl)methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-5-carboxylic acid;
4-[[2-butyl-5-[(1,2-dihydro-5-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoic acid;
3-[[2-butyl-1-[[2'-carboxy-[1,1'-biphenyl]-4-yl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid;
4-[[2 -butyl-5-[(1,2-dihydro-1-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoic acid;
4-[[5-[[1-(aminocarbonyl)-1,2-dihydro-2-oxo-3H-indol-3-ylidene]methyl]-2-butyl-1H-imidazol-1-yl]methyl]benzoic acid;
Methyl 4-[[(2-propyl-5-[1,2-dihydro-1-(methylaminocarbonyl)-2-oxo-3H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl benzoate;
Methyl 4-[[2-butyl-5-[1,2-dihydro-1-hydroxy-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate;
Ethyl (Z)-(±)-2,3-dihydro-3-[[3-[[4-(methoxycarbonyl) phenyl]methyl]-2-propyl-3H-imidazol-4-yl]methylene]-4-methyl-2-oxo-α-propyl-1H-indole-1-acetate;
3-[[2-butyl-3-[[4-(1H-tetrazol-5-yl)phenyl]methyl]-3 H-imidazol-4-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid;
Methyl (Z)-2,3-dihydro-3-[[3-[[4-(methoxycarbonyl)phenyl]methyl]-2-propyl-3H-imidazol-4-yl]methylene]-4-methyl-2-oxo-1H-indole-1-acetate;
4-[[2-butyl-5-[(1-butyl-1,2-dihydro-2-oxo-3H-indol-3-ylidenyl)methyl]-1H-imidazol-1-yl]methyl]-3 chlorobenzoic acid;
4-[[2-butyl-5-[(1,2-dihydro-7-methyl-2-oxo-3H-indol-3-ylidenyl)methyl]-1H-imidazol-1-yl]methyl]benzoic acid;
4-[[5-[(1,2-dihydro-2-oxo-1-propyl-3H-indol-3-ylidenyl)methyl]-2-propyl-1H-imidazol-1-yl]methyl]benzoic acid;
(E)-4-[[5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidenyl)methyl]-2-propyl-4-(1H-pyrrol-1-yl)-1H-imidazol-1-yl]methyl]benzoic acid;
Ethyl (Z)-3-[[2-butyl-3-[[4-(methoxycarbonyl)phenyl]methyl]-3H-imidazol-4-yl]methylene]-2,3-dihydro-7-methoxy-2-oxo-1H-indole-1-acetate;
Methyl 4-[[5-[(1,2-dihydro-1-methyl-2-oxo-3H-indol-3-ylidenyl)methyl]-2-propyl-1H-imidazol-1-yl]methyl]benzoate;
Methyl 2,3-dihydro-3-[[3-[[4-(methoxycarbonyl)phenyl]methyl]-2-propyl-3H-imidazol-4-yl]methylene]-2-oxo-1H-indole-7-acetate;
(E)-3-[[3-[(4-carboxyphenyl)methyl]-2-propyl-3H-imidazol-4-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid;
Benzoic acid, 4-[[2-butyl-5-[[1-[(4-chlorophenyl)methyl]-2,3-dihydro-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, (E)-;
1H-Indole-1-propanoic acid, 3-[[2-butyl-1-[(4-carboxyphenyl)methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo -, (E)-;
Benzoic acid, 4-[[2-butyl-5-[[2,3-dihydro-2-oxo-1-[(1H-tetrazol-5-yl)methyl]-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester, (E)-;
1H-Indole-1-propanoic acid, 3-[[2-butyl-1-[[4-methoxycarbonyl)phenyl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-, ethyl ester, (E)-;
Benzoic acid, 4-[[2-butyl-5-[[1-(cyanomethyl)-2,3-dihydro-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester, (E);
Benzoic acid, 4-[[2-butyl-5-[[1-[2-(dimethylamino) ethyl]-2,3-dihydro-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester, (E)-;
1H-Indole-1-acetic acid, 3-[[2-butyl-1-[[4-(1H-tetrazol-5-yl) phenyl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-, methyl ester;
Benzoic acid, 4-[[5-[(2,3-dihydro-1-methyl-2-oxo-1H-indol-3-ylidene)methyl]-2-propyl-4-(1H-pyrrol-1-yl)-1H-imidazol-1-yl]methyl]-, methyl ester, (E)-;
Benzoic acid, 4-[[2-butyl-5-[(1-butyl-2,3-dihydro-2-oxo-1H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]-, methyl ester;
1H-Indole-1-acetic acid, 2,3-dihydro-3-[[1-[[4-(methoxycarbonyl) phenyl]methyl]-2-propyl-4-(1H-pyrrol-1-yl)-1H-imidazol-5-yl]methylene]-2-oxo -, methyl ester, (E);
Benzoic acid, 4-[[5-[[2,3-dihydro-1-(1-methylethyl)-2-oxo-1H-indol-3-ylidene]methyl]-2-propyl-1H-imidazol-1-yl]methyl]-, methyl ester, (Z)-;
Benzoic acid, 4-[[5-[(1-butyl-2,3-dihydro-2-oxo-1H-indol-3-ylidene)methyl]-2-propyl-4-(1H-pyrrol-1-yl)-1H-imidazol-1-yl]methyl]-, methyl ester, (E)-;
Benzoic acid, 4-[[2-butyl-5-[[2,3-dihydro-1-(2-methoxy-2-oxoethoxy)-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester;
1H-Indole-1-acetic acid, 3-[[2-butyl-1-[[4-(1H-tetrazol-5-yl) phenyl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-, ethyl ester;
Benzoic acid, 4-[[5-[(2,3-dihydro-2-oxo-1H-indol-3-ylidene)methyl]-2-ethyl-4-methyl-1H-imidazol-1-yl]methyl]-(E)-;
2 (1H)-Isoquinolineacetic acid, 3,4-dihydro-4-[[1-[[4-(methoxycarbonyl)phenyl]methyl]-2-propyl-1H-imidazol-5-yl]methylene]-1,3-dioxo-, methyl ester, (Z)-;
Benzoic acid, 4-[[2-butyl-5-[(2,3-dihydro-2-oxo-1H-indol-3-yl)methyl]-1H-imidazol-1-yl]methyl]-, methyl ester; and their pharmaceutically acceptable salts.
Both the E and Z isomers are within the scope of the invention.
The E-isomers (trans stereochemistry of the carbonyl and imidazole groups) are generally more active and thus, are preferred over the Z-isomers.
The compounds of the instant invention include solyates, hydroares, and pharmaceutically acceptable acid addition and/or base salts of the compounds of Formula I above.
The term pharmaceutically acceptable acid addition salt is intended to mean a relatively nontoxic acid addition salt either from inorganic or organic acids such as, for example, hydrochloric, hydrobromic, hydroiodic, sulfuric, phosphoric, acetic, citric, oxalic, malonic, salicylic, malic, benzoic, gluconic, fumaric, succinic, ascorbic, maleic, tartaric, methanesulfonic, and the like. The salts are prepared, when applicable, by contacting the free base form with a sufficient amount of the desired acid to produce a salt in the conventional manner. The free base forms may be regenerated by treating the salt form with a base.
When the compounds are in the free carboxylic acid form the pharmaceutically suitable salts also include both the metallic (inorganic) salts and organic salts; a list of which is given in Remington's Pharmaceutical Sciences, 17th Edition, 1985:1418. It is well known to one skilled in the art that an appropriate salt form is chosen based on physical and chemical stability, flowability, hydroscopicity, and solubility. Preferred salts of this invention for the reasons cited above include potassium, sodium, calcium, and ammonium salts.
The compounds of the present invention possess one or more chiral centers and each center may exist in the R(D) or S(L) configuration. The present invention includes all enantiomeric and epimeric forms as well as the appropriate mixtures thereof.
The instant invention includes a process for the preparation of compounds of Formula I.
The term lower alkyl refers to straight or branched chain alkyl radicals containing from one to ten carbon atoms except where specifically stated including but not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, sec-butyl, 2-methylhexyl, n-pentyl, 1-methylbutyl, 2,2-dimethylbutyl, 2-methyl-pentyl, 2,2-dimethylpropyl, n-hexyl, and the like.
The term halogen refers to bromine, chlorine, iodine, and fluorine.
The term cycloalkyl refers to cyclic alkyl groups containing three to six carbon atoms.
The term aryl refers to phenyl and 1- or 2-naphthyl, unsubstituted or substituted by CH 3 , OCH 3 , OH, Br, Cl, F, NO 2 , NH 2 , N(CH 3 ) 2 , SCH 3 , SH.
Heteroaryl refers to 5- or 6-membered rings or 8-, 9-, or 10-membered twin rings containing one or more heteroatoms selected from N, O, S, and includes but is not limited to: pyrrole, imidazole, thiophene, furane, pyridine, thiazole, indole, morpholine, isoquinoline.
Scheme I below illustrates one of the preparation of known starting materials (J Med Chem 1991; 34:1514-7, U.S. Pat. No. 4,207,324, and U.S. Pat. No. 4,355,040), the disclosure of which is hereby incorporated by reference.
Scheme II outlines another procedure useful for compounds wherein R 3 is a group other than halo.
The 1--R 1 CH-group is incorporated onto the 2-R 2 X-imidazole by known procedures, for example, by reaction with an R 1 --CH 2 halide, mesylate or acetate, such as 2-chlorobenzyl bromide, in a suitable solvent, such as dimethylformamide (DMF), in the presence of a suitable acid acceptor, such as sodium alkylate, potassium or sodium carbonate, or a metal hydride, preferably sodium hydride, at a reaction temperature of 25°-100° C., preferably 50° C. The resulting 1--R 1 CH 2 --2--R 2 imidazole is hydroxymethylated in the 5-position, for example, by reacting with formaldehyde in the presence of sodium acetate in acetic acid to provide the 1--R 1 --CH 2 --2--R 2 X--5 hydroxymethylimidazole intermediates.
The hydroxymethyl group of the hereinbefore prepared intermediate is oxidized to an aldehyde by treatment with a suitable reagent, such as anhydrous chromic acid silica gel in tetrahydrofuran or, preferably, with activated manganese dioxide, in a suitable solvent such as benzene, or toluene, or preferably methylene chloride, at a temperature of 25°-140° C., preferably at 25° C.
Alternatively the 1--R 1 CH 2 --2--R 2 --5 hydroxymethylimidazole intermediates are prepared by reacting an amidine, R 2 --C(═NH)--NH 2 such as valeramidine, with dihydroxyacetone in liquid ammonia under pressure to give 2--R 2 --5-hydroxymethylimidazole (Irabach J L, Jacquier R, Lacombe J M, Mawry G, Bull Soc Chim Fr 1971:1052). This intermediate is reacted with acetic anhydride to give 1-acetyl-5-acetoxymethyl-2--R 2 -imidazole. The diacetate intermediate is N alkylated, for example, using 2-chlorobenzyl triflate and the resulting 1--R 1 CH 2 -2--R 2 --5-acetoxymethylimidazole is treated with aqueous base, such as 10% sodium hydroxide solution to give the 1--R 1 CH 2 --2--R 2 --5-hydroxymethylimidazole intermediate which can be oxidized as before to the aldehyde 2b (see Scheme
Scheme IV below illustrates the synthesis of the compounds of structure 1. Compounds of the structure 2 are reacted with the requisite oxo-methylene substrate, for example, 6 under acid catalyzed (Method A) or base catalyzed (Method B) condition to afford 3. Compounds 3 are treated with base, such as KOH, LiOH, or NaOH in aqueous alcohol or diglyme, to yield the desired carboxylic acid 5. Alternatively, compounds 2 are treated with base to give acids 4 which are then reacted with 6 to provide compounds 5. Method A uses acid such as, but not limited to, acetic acid, propionic acid, etc., containing p-toluene sulfonic acid, β-alanine, anhydrous NaAc, trifluoro acetic anhydride, acetic anhydride, etc. Method B uses solvents such as, but not limited to, ethanol, toluene, xylene-containing piperidine, Et 3 N, sodium methoxide, etc.
The (E)- and (Z)-isomers are separated either at the ester stage (compound 3) by column chromatography or at the acid stage (compound 5) by crystallization.
For compounds where the substituted oxindoles are not easily accessible are obtained from compound 3 via alkylation as shown in Scheme V. Compound 3 is treated with the requisite alkyl halide in the presence of a base (for example, Cs 2 CO 3 ) in DMF to give compound of structure 7. This can be treated with NaOH in aqueous alcohol to give the desired acid 8.
The 1--R 1 CH--2--R 2 X-imidazol-5-carboxaldehydes are reacted with an appropriate phosphonate (Scheme VI). The phosphonates are prepared, for example, from trialkyl phosphonoacetates by alkylation with an appropriate halide, mesylate or acetate in the presence of a suitable base, such as sodium hydride, DBU in a suitable solvent, preferably glyme at a reaction temperature of 25°-100° C., preferably at 55° C. The reaction of the imidazol 5 carboxaldehydes with the phosphonates is performed in the presence of a suitable base, such as a metal alkoxide, lithium hydride or, preferably, sodium hydride, in a suitable solvent, such as ethanol, methanol, ether, dioxane, tetrahydrofuran or, preferably glyme, at a reaction temperature of 10°-50° C., preferably, at 25° C., to provide a variable mixture of trans and cis, e.g., (E) and (Z). The trans and cis structures of the acids are readily determined by NMR by the NOE protocol, as well as by the biological activities since, generally, the trans (E)-isomers are the more potent isomers.
Compounds of structure (I) are also prepared as follows. The 1--R 1 --(CH 2 )--2--R 2 X-imidazol-5-carboxaldehydes are treated with the lithium derivative of an active methylene substrate, such as 6. These lithio derivatives are prepared from the reaction of lithium diisopropylamide in as suitable solvent, preferably tetrahydrofuran, with an acid ester, such as ROOC--CH 2 --Y-phenyl, to generate the α-lithio derivatives at -78° to -10° C., preferably at -78° C., which are then treated with the imidazolcarboxaldehyde. The intermediates β-hydroxy group of the imidazole ester is converted to a mesylate or an acetate and the mesylate, or preferably the acetate, is heated in a suitable solvent, such as toluene, with one to two equivalents of 1,8-diazobicyclo[5.4.0]undec-7-ene, at 50°-110° C., preferably at 80° C., to afford compounds of structure (1). The (E)-isomer is the predominate olefinic isomer. The acids are prepared from the esters by the method described above.
The starting materials 6 are prepared by known procedures.
Another alternative procedure to prepare compounds of structure I is outlined in Scheme VII. The 4-chloro-5-formyl imidazole is reduced to give the 5-formyl imidazole (10) which reacted with oxindole 9 (or 6) in the presence of a base as before to give the condensation product 11. This is converted to the N-protected (for example, Boc, trityl, acetyl, POM, etc.) imidazole derivative 12 by reacting with BOC-chloride in the presence of a base in DMF. Compound 12 is converted to the target compound 3 by triflic anhydride/requisite benzyl alcohol method.
Scheme VIII outlines the synthesis of compound 2 wherein the ester functionality is replaced with a tetrazole moiety. p-Tolunitrile is converted to the tetrazole compound via standard reaction condition using NaN 3 /NH 4 Cl/DMF. The tetrazole is protected with a trityl group by the reaction of tritylchloride in the presence of Et 3 N in DMF. This is converted to the corresponding bromide which is then condensed with the imidazole 1 as before to give the desired chloroaldehyde. This is converted to the corresponding hydrogen compound 13 by catalytic reduction. This is reacted with the oxindole to give compound 14 as described before. This is converted to the free tetrazole compound 15 by treatment with MeOH. Alternatively, compound 14 is alkylated to introduce a substitution at the nitrogen by treatment with the desired alkyl halide in presence of a base. Subsequent treatment with MeOH gives compound 16. In addition, compound 16, wherein R' is a CO 2 Me (or CO 2 Et) group, is saponified to give the desired acid 17.
One example of the synthesis of the starting material where R 3 is a heterocycle is shown in Scheme IX. The requisite imidate-HCl is reacted with ethyl amino cyano acetate (Shaw et al, Chemistry and Industry 1981:542) in the presence of KOAc in methanol to give the 4-amino imidazole-5-carboxylate derivative. This is treated with 2,5-dimethoxy tetrahydrofuran in AcOH under refluxing condition to give the desired pyrrole derivative. The ester moiety is converted to the carboxaldehyde 18 in two steps which is used for N-benzylation as before.
Scheme X outlines a general procedure to prepare compounds of Formula I where the double bond is reduced. ##STR8##
For preparing pharmaceutical compositions from the compounds described by this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, cachets, and suppositories. A solid carrier can be one or more substances which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders, or tablet disintegrating agents. It can also be encapsulating material. In powders, the carrier is a finely divided solid which is in admixture with the finely divided active compound. In the tablet the active compound is mixed with a carrier having the necessary binding properties in suitable proportions and compacted in the shape and size desired. The powders and tablets preferably contain from 5 to 10% to about 70% of the active ingredient. Suitable solid carriers are magnesium carbonate, magnesium stearate, talc, sugar, lactose, pectin, dextrin, starch, gelatin, tragacanth, methylcellulose, a low melting wax, cocoa butter, and the like. The term "preparation" is intended to include the formulation of the active compound with encapsulating material as carrier providing a capsule in which the active component (with or without other carriers) is surrounded by carrier, which is thus in association with it. Similarly, cachets are included. Tablets, powders, cachets, and capsules can be used as solid dosage forms suitable for oral administration.
The compounds of the present invention may be administered orally, buccally, parentsrally, by inhalation spray, rectally, or topically in dosage unit formulations containing conventional nontoxic pharmaceutically acceptable carriers, adjuvants, and vehicles as desired. The term parenteral as used herein includes subcutaneous injections, intravenous, intramuscular, intrasternal injection, or infusion techniques.
For preparing suppositories, a low melting wax such as a mixture of fatty acid glycerides or cocoa butter is first melted, and the active ingredient is dispersed homogeneously therein by stirring. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool, and thereby solidify.
Liquified form preparations include solutions, suspensions, and emulsions. As an example may be mentioned water or water/propylene glycol solutions for parenteral injection. Liquid preparations can also be formulated in solution in aqueous polyethyleneglycol solution. Aqueous suspensions suitable for oral use can be made by dispersing the finely divided active component in water with viscous material, i.e., natural or synthetic gums, resins, methylcellulose, sodium carboxymethyl-cellulose, and other well-known suspending agents.
Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for either oral or parenteral administration. Such liquid forms include solutions, suspensions, and emulsions. These particular solid form preparations are most conveniently provided in unit dose form and as such are used to provide a single liquid dosage unit. Alternately, sufficient solid may be provided so that after conversion to liquid form, multiple individual liquid doses may be obtained by measuring predetermined volumes of the liquid form preparation as with a syringe, teaspoon, or other volumetric container. When multiple liquid doses are so prepared, it is preferred to maintain the unused portion of said liquid doses at low temperature (i.e., under refrigeration) in order to retard possible decomposition. The solid form preparations intended to be converted to liquid form may contain, in addition to the active material, flavorants, colorants, stabilizers, buffers, artificial and natural sweeteners, dispersants, thickeners, solubilizing agents, and the like. The liquid utilized for preparing the liquid form preparation may be water, isotonic water, ethanol, glycerin, propylene glycol, and the like, as well as mixtures thereof. Naturally, the liquid utilized will be chosen with regard to the route of administration, for example, liquid preparations containing large amounts of ethanol are not suitable for parenteral use.
Preferably, the pharmaceutical preparation is in unit dosage form. In such form, the preparation is subdivided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, for example, packeted tablets, capsules, and powders in vials or ampules. The unit dosage form can also be a capsule, cachet, or tablet itself, or it can be the appropriate number of any of these in packaged form.
The quantity of active compound in a unit dose of preparation may be varied or adjusted from 1 to 500 mg, preferably 5 to 100 mg according to the particular application and the potency of the active ingredient. The compositions can, if desired, also contain other compatible therapeutic agents.
In therapeutic use as antihypertensive agents, the mammalian dosage range for a 70 kg subject is from 0.1 to 500 mg/kg of body weight per day or preferably 1 to 500 mg/kg of body weight per day optionally in divided portions. The dosages, however, may be varied depending upon the requirements of the patient, the severity of the condition being treated, and the compound being employed. Determination of the proper dosage for a particular situation is within the skill of the art. Generally, treatment is initiated with smaller dosages which are less than the optimum dose of the compound. Thereafter the dosage is increased by small increments until the optimum effect under the circumstances is reached. For convenience, the total daily dosage may be divided and administered in portions during the day if desired.
The effectiveness of the compounds of the instant invention is determined by a test (RBAT 1 ) entitled Receptor Binding of Angiotensin II. In this in vitro test the inhibition of tritiated angiotensin II binding to rat liver membranes is measured (Dudley D T, et al, Molecular Pharmacology 1990;38:370-7).
______________________________________Example RBAT.sub.1 Example RBAT.sub.1Name IC.sub.50, nM Name IC.sub.50, nM______________________________________1D 75 4C 3582B 610 4E 722C 201 4E 722D 86 4F 2562F 67 4G 642G 746 4H 2263 170 4I 3003A 140 4J 6863B 120 4K 1103C 22 4M 543F 123 5 943G 20 6 253H 52 6A 123I 140 7 5.74 590 8 474A 640 9 984B 95 10 53______________________________________
Based on the observations that ACE inhibitors are known to benefit patients with heart failure, the instant compound which also interrupts the renin angiotensin system (RAS), would show similar benefits.
The following examples are provided to enable one skilled in the art to practice the present invention. These examples are not intended in any way to limit the scope of the invention but are illustrative thereof.
EXAMPLE 1
Ethyl 4-[[2-butyl-5-[(1,2-dihydro-2-oxo-3H-indol-3ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
A mixture of 0.8 9 (2.85 mmol) of 2-butyl-1-(4-carbethoxy)benzyl-5-formyl-imidazole, 0.3 9 (2.85 mmol) of oxindole and β-alanine (20 m 9 ) in AcOH (15 mL) was heated at reflux for 18 hours. AcOH was distilled off and the residue was treated with EtOAc. The solid (09.7 g) was filtered off and recrystallized from EtOAc to give 0.27 g of yellow solid (E-isomer), mp 272°-273° C.
Analysis calculated for C 26 H 27 N 3 O 3 : C, 72.71; H, 6.34; N, 9.78. Found: C, 72.52; H, 6.41; N, 9.75. MS (CI) 430 (m). Second crop; (Z-isomer); 0.3 g; mp 169°-171° C. Analysis Found: C, 72.62; H, 6.42; N, 9.54. MS (CI) 430 (m). H NMR indicate the presence of 15% of E-isomer.
The following were prepared using the procedure described above.
EXAMPLE 1A
Methyl 4-[[2-butyl-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]-3-chlorobenzoate
E-isomer; mp 219°-220° C.; MS (CI) 450 (m) . Analysis calculated for C 25 H 24 ClN 3 O 3 .H 2 O: C, 65.43; H, 5.49; N, 9.16. Found: C, 65.43; H, 5.27; N, 9.08.
Z-isomer; mp 195°-196° C.; MS (CI) 450 (m). Calculated for C 25 H 24 ClN 3 O 3 .0.3 H 2 O: C, 65.95; H, 5.46; N, 9.15. Found: C, 65.95; H, 5.46; N, 9.15.
EXAMPLE 1B
Methyl 4-[[2-butyl-5-[(1,2-dihydro-5-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
Mixture of E- and Z-isomers; MS (CI) 430 (m) . Analysis calculated for C 26 H 27 N 3 O 3 : C, 72.71; H, 6.34; N, 9.78. Found: C, 72.47; H, 6.21; N, 9.56. mp 195°-200° C.
EXAMPLE 1C
Ethyl 4-[[2-butyl-4-chloro-5-[(1,2-dihydro-6-methyloxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
Mixture of E- and Z-isomer; MS (CI) 478 (m) . Analysis calculated for C 27 H 28 ClN 3 O 3 : C, 67.85; H, 5.90; N, 8.79. Found: C, 67.41; H, 6.07; N, 8.52.
EXAMPLE 1D
Methyl 4-[[2-propyl-5-[(1,2-dihydro-1-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
E-isomer; mp 181°-182° C.; MS (CI) 415 (m). Analysis calculated for C 25 H 25 N 3 O 3 : C, 72.27; H, 6.06; N, 10.11. Found: C, 72.22; H, 5.94; N, 9.97.
Z-isomer; MS (CI) 415 (m); mp 146°-148° C. Analysis calculated for C 25 H 25 N 3 O 3 .0.53 H 2 O: C, 70.68; H, 6.18; N, 9.89. Found: C, 70.65; H, 6.16; N, 9.82.
EXAMPLE 1E
Methyl 4-[[2-butyl-5-[(1,2-dihydro-4-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
Z-isomer; mp 205°-207° C.; MS (CI) 430 (m). Analysis calculated for C 26 H 27 N 3 O 3 : C, 72.71; H, 6.34; N, 9.78. Found: C, 72.25; H, 6.13; N, 9.56.
EXAMPLE 1F
Methyl 4-[[2-butyl-5-[(1,2-dihydro-7-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
E-isomer; mp 198°-200° C.; MS (CI) 430 (m). Analysis calculated for C 26 H 27 N 3 O 3 : C, 72.71; H, 6.34; N, 9.78. Found: C, 72.33; H, 6.21; N, 9.63.
Z-isomer; mp 221°-223° C.; MS (CI) 430 (m). Analysis calculated for C 26 H 27 N 3 O 3 : C, 72.71; H, 6.34; N, 9.78. Found: C, 72.67; H, 6.13; N, 9.88.
EXAMPLE 1G
Methyl 4-[[2-butyl-5-[(5-chloro-1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
Z-isomer; mp 238°-241° C.; MS (CI) 450 (m) . Analysis calculated for C 25 H 24 ClN 3 O 3 .0.25 EtOAc: C, 66.17; H, 5.55; N, 8.90. Found: C, 65.77; H, 5.45; N, 9.02.
EXAMPLE 1H
Methyl 4-[[2-butyl-5-[(1,2-dihydro-7-methoxy-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
E-isomer; MS (CI) 446 (m).
Z-isomer; mp 190°-195° C.; MS (CI) 446 (m) . Analysis calculated for 0.45 EtOAc: C, 68.82; H, 6.36; N, 8.66. Found: C, 68.58; H, 5.94; H, 8.36.
EXAMPLE 1I
Ethyl 3.-[[2-butyl-1-[[4-(methoxycarbonyl)phenyl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-5-carboxylate
Z-isomer; MS (CI) 488 (m); mp 211°-215° C. Analysis calculated for: C, 68.98; H, 6.00; N, 8.62. Found: C, 68.64; H, 6.11; N, 8.49.
EXAMPLE 2
Ethyl 4-[[2-butyl-4-chloro-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
A mixture of 0.87 g (2.5 mmol) of 2-butyl-1-(4-carbethoxy)benzyl-4-chloro-5-formyl-imidazole), 0.33 g (2.5 mmol) of oxindole and 0.1 mL of piperidine in toluene (30 mL) was heated at reflux with a Dean-Stark apparatus for 24 hours. The solution was diluted with toluene, washed with water, dried, and stripped to give a dark brown solid. This was purified via column chromatography (silica gel, hexane/ethyl acetate, 10% to 50%) to yield 0.75 g of a dark yellow foam.
MS (CI) 464 (m). Analysis calculated for C 26 H 26 ClN 3 O 3 : C, 67.31; H, 5.65; N, 9.06. Found: C, 67.65; H, 5.58; N, 8.99. 1 H NMR indicate a mixture of E-/Z-isomer ratio of 4/1.
EXAMPLE 2A
Ethyl 3-[[2-butyl-1-(4-methoxycarbonyl)phenyl]methyl]-1H-imidazol yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetate
Z(83%)/E(17%); mp 233°-235° C.; MS (CI) 502 (m). Analysis calculated for C 29 H 31 N 3 O 5 0.72 H 2 O: C, 67.67; H, 6.36; N, 8.15. Found: C, 67.66; H, 6.52; N, 8.15.
E(89%)/Z(11%); mp 200°-201° C.; MS (CI) 502 (m). Analysis calculated for C 29 H 31 N 3 O 5 : C, 69.44; H, 6.23; N, 8.38. Found: C, 69.10; H, 6.34; N, 8.29.
EXAMPLE 2B
Methyl 4-[[(2-propyl-5-[1,2-dihydro-1-(methylaminocarbonyl)-2-oxo-3H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl benzoate
Z(78%)/E(22%); MS (FAB) 459 (m); mp 76°-80° C. Analysis calculated for C 26 H 26 N 4 O 4 0.31 H 2 O: C, 67.29; H, 5.78; N, 12.07. Found: C, 67.30; H, 5.82; N, 11.99.
E(71%)/Z(29%); MS (CI) 459 (m); mp 73°-76° C. Analysis calculated for C 26 H 26 N 4 O 4 0.4 H 2 O: C, 67.05; H, 5.80; N, 12.03. Found: C, 67.05; H, 5.89; N, 11.91.
EXAMPLE 2C
Methyl 4-[[2-butyl-5-[1,2-dihydro-1-hydroxy-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
Mixture of E- and Z-isomers. A mixture of the aldehyde (0.488 g; 1.63 mM) and N-hydroxyoxindole (Kende AS, et al, Synthetic Comm 1990;20:2133) (0.25 g; 1.68 mM) in abs. EtOH (6.0 mn) is treated with 4 drops of piperidine and the solution is heated to reflux for 4.0 hours. On cooling, the product crystallizes containing ethanol as solvent of crystallization. Yield 0.473 g (62.7%); mp 198°-200° C.
MS (CI) 432 (m).
EXAMPLE 2D
(E)-4-[[5-[(1,2-dihydro-2-oxo-3H-indol-3-ylideny)methyl]-2-propyl-4-(1H-pyrrol-1-yl)-1H-imidazol-1-yl]methyl]benzoic acid
MS (FAB) 453 (m). Analysis calculated for C 27 H 22 N 4 O 3 Na 2 .0.43 H 2 O: C, 64.32; H, 4.57; N, 11.11. Found: C, 64.70, H, 4.97; N, 10.77.
EXAMPLE 2E
Methyl-4-[[2-butyl-5-[1,2-dihydro-2-oxo-3H-indol-3ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoate
MS (CI) 416 (m); mp 264°-265° C.
EXAMPLE 2 F
Benzoic acid, 4-[[5-[[2,3-dihydro-1-(1-methylethyl)-2-oxo-1H-indol-3-ylidene]methyl]. -2-propyl-1H-imidazol-1-yl]methyl]-, methyl ester, (Z)
By following the methodology of Example 2 and substituting the properly substituted oxindole in place of oxindole additional analogs were obtained.
MS (CI) 444 (m); Analysis calculated for C 27 H 29 N 3 O 3 .0.5 tBuOH-0.4 H 2 O: C, 71.89; H, 6.72; N, 9.25; Found: C, 71.94; H, 6.77; N, 9.10.
EXAMPLE 2G
Methyl 4-[[5-[(1,2-dihydro-2-oxo-1-propyl-3H-indol-3-ylidenyl)methyl]-2-propyl -1H-imidazol-1-yl]methyl]benzoate
MS (CI) 444 (m). Analysis calculated for C 27 H 29 N 3 O 3 .0.5 H 2 O: C, 71.66; H, 6.68; N, 9.29. Found: C, 71.64, H, 6.55; N, 9.19.
EXAMPLE 2H
Benzoic acid, 4-[[5-[(2,3-dihydro-2-oxo-1H-indol-3ylidene)methyl]-2-ethyl-4-methyl-1H-imidazol-1-yl]methyl]-(E)
By replacing the 5-formyl-imidazole in Example 2 with the 5-formyl-imidazole from Example 11D and following the methodology described in Example 2, the title compound was obtained. MS (CI) 387, (m).
Analysis calculated for C 23 H 21 N 3 O 3 .0.8 H 2 O: C, 68.75; H, 5.67; N, 10.46. Found: C, 68.51; H, 5.53; N, 10.13. 1 H NMR indicate 10% of the Z-isomer.
EXAMPLE 3
4-[[2-Butyl-5-[(1,12-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoic acid
A mixture of 0.4 g of compound 1 (E- and Z-isomer, Example 1) in methanol (10 mL) and a solution of 80 mg of NaOH in 0.35 mL of water was heated at reflux for 4 hours. Methanol was stripped and the solution was diluted with water and extracted with EtOAc. The aqueous solution was acidified to pH 4 and the solid was filtered, washed with water, and dried in a vacuum oven at 80° C. for 14 hours to give 0.35 g of the product, mp 237°-238° C.; MS (CI) 401 (m).
Analysis calculated for C 24 H 23 N 3 O 3 : C, 71.80; H, 5.77; N, 10.47. Found: C, 66.98; H, 5.66; N, 10.25.
The following were prepared by using the procedure described above.
EXAMPLE 3A
(E)-4-[[2-Butyl-4-chloro-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)]-1H-imidazol-1-yl]methyl]benzoic acid
MS (CI) 436 (m); crystallized from EtOAc to give analytically pure sample, mp 241°-242° C. Analysis calculated for C 24 H 22 ClN 3 O 3 : C, 66.13; H, 5.09; N, 9.64; C 1 , 8.13. Found: C, 65.75; H, 5.06; N, 9.45; Cl, 8.20.
EXAMPLE 3B
4-[[2-Butyl-5-[(1,2-dihydro-7-methoxy -2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoic acid
E-and Z-isomer (1:1); MS (CI) 432 (m); mp 248°-251° C. Analysis calculated for C 25 H 25 N 3 O 4 .0.8 H 2 O: C, 67.34; H, 6.01; N, 9.42. Found: C, 67.06; H, 5.98; N, 9.25.
EXAMPLE 3C
3-[[2-Butyl-1-[(4-carboxyphenyl)methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid
E-and Z-mixture (1:1); MS (EI) 460 (m). Analysis calculated for C 26 H 25 N 3 O 5 .1.28 H 2 O: C, 64.74; H, 5.50; N, 8.51.
EXAMPLE 3D
3-[[2-Butyl-1-[(4-carboxyphenyl)methyl]-1H-imidazol-5yl]methylene]-2,3-dihydro-2-oxo-1H-indole-5-carboxylic acid
E- and Z-isomer (1:1); MS (EI) 445 (m). Analysis calculated for C 25 H 23 N 3 O 5 .0.81 H 2 O: C, 65.27; H, 5.39; N, 9.13. Found: C, 65.26; H, 5.33; N, 9.15.
EXAMPLE 3E
4-[[2-Butyl-5-[(1,2-dihydro-5-methyl-2-oxo-3H-indol-3-ylidenemethyl]-1H-imidazol-1-yl]methyl]benzoic acid
E-and Z-isomer (1:1); MS (CI) 416 (m). Analysis calculated for C 25 H 25 N 3 O 3 .1.65 H 2 O: C, 67.44; H, 6.41; N, 9.44. Found: C, 67.15; H, 6.02; N, 9.36.
EXAMPLE 3 F
4-[[2-Butyl-5-[(1,2-dihydro-1-methyl-2-oxo-3H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]benzoic acid
Mixture of E- and Z-isomers. A mixture of the ester from Example 2C (126 mg; 0.27 mM), MeOH (10 mL), and water (10 mL) is treated with 1 N NaOH (1.5 mL) when the mixture turns into a dark solution. The solution is heated on a steam bath for 5 minutes and is then concentrated to a small volume, diluted with water, and filtered. The aqueous solution is carefully acidified with acetic acid (1.5 mL) when the product slowly crystallizes out as mono hydrate. It is filtered, washed with water, and dried. Yield 119 mg (99%); mp 185°-188° C. MS (FAB) 418 (M+1).
Analysis calculated for C 24 H 23 N 3 O 4 .1 H 2 O: C, 66.19; H, 5.79; N, 9.65. Found: C, 66.32; H, 5.67; N, 9.60.
EXAMPLE 3G
1H-Indole-1-propanoic acid, 3-[[2-butyl-1-[(4-carboxyphenyl)methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo -, (E)
MS (CI) 474 (m). Analysis calculated for C 27 H 27 N 3 O 5 .0.9 H 2 O: C, 66.22; H, 5.93; N, 8.58. Found: C, 66.30; H, 5.82; N, 8.32.
EXAMPLE 3H
4-[[2-butyl-5-[(1-butyl-1,2-dihydro-2-oxo-3H-indol-3-ylidenyl)methyl]-1H-imidazol-1-yl]methyl]-3 chlorobenzoic acid
MS (FAB) 492 (m). Analysis calculated for C 28 H 30 ClN 3 O 3 .CH 2 Cl 2 .2.5 H 2 O: C, 56.00; H, 6.00; N, 6.76. Found: C, 55.74; H, 5.99; N, 6.46.
EXAMPLE 3I
4-[[5-[(1,2-dihydro-2-oxo-1-propyl-3H-indol-3-ylidenyl)methyl]-2-propyl-1H-imidazol-1-yl]methyl]benzoic acid
(FAB) 416 (m).
EXAMPLE 4
Benzoic acid, 4-[[5-[(1-butyl-2,3-dihydro-2-oxo-1H-indol-3-ylidene)methyl]-2=propyl-4=(1H-pyrrol-1-yl)-1H-imidazol-1-yl]methyl]-, methyl ester, (E)
To a solution of 0.46 g (1 mmol) of the methylester of compound from Example 2D in DMF (6 mL) was added CS 2 CO 3 (0.65 g, 2 mmol). This reaction mixture was stirred for 15 minutes followed by the addition of a solution of nBuBr (0.27 g, 2 mmol) in DMF (5 mL). The solution was stirred for 5 hours at room temperature. DMF was distilled under high vacuum, the residue was dissolved in water and the solution was extracted with EtOAc. The extract was washed with water, dried, and stripped. The residue was triturated with ether/EtOAc to yield a solid which was filtered to give 0.35 g of the titled product, MS 523 (m), mp 135°-136° C.
Analysis calculated for C 32 H 34 N 4 O 3 : C, 73.54; H, 6.56; N, 10.72. Found: C, 73.05; H, 6.51; N, 10.40.
The following were prepared by using the methodology described above.
EXAMPLE 4A
Benzoic acid, 4-[[5-[(2,3-dihydro-1-methyl-2-oxo-1H-indol-3-ylidene)methyl]-2-propyl-4-(1H-pyrrol-1-yl)-1H-imidazol-1-yl]methyl]-, methyl ester, (E)
MS (CI) 481 (m); mp 163°-164° C. Analysis calculated for C 29 H 28 N 4 O 3 .0.29 CH 2 Cl 2 : C, 69.64; H, 5.70; N, 11.09. Found: C, 70.02; H, 6.02; N, 10.70.
EXAMPLE 4B
1H-Indole-1-acetic acid, 2,3-dihydro-3-[[1-[[4-(methoxycarbonyl)phenyl]methyl]-2-propyl-4-(1H-pyrrol-1-yl)-1H-imidazol-5-yl]methylene]-2-oxo-, methyl ester, (E)
Yellow foam; MS (CI) 539 (m). Analysis calculated for C 31 H 30 N 4 O 5 .0.64 EtOAc: C, 67.75; H, 5.62; N, 9.61. Found: C, 67.36; H, 5.62; N, 9.42.
Replacing compound from Example 2D with 2E, and following the procedure of Example 4 using requisite alkyl halide additional analogs have been prepared.
EXAMPLE 4C
Benzoic acid, 4-[[2-butyl-5-[(1-butyl-2,3-dihydro-2-oxo-1H-indol-3-ylidene)methyl]-1H-imidazol-1-yl]methyl]-, methyl ester
Yellow foam; MS (CI) 472 (m). Analysis calculated for C 29 H 33 N 3 O 3 .0.1 EtOAc: C, 73.50; H, 7.09; N, 8.75. Found: C, 73.17; H, 7.26; N, 8.78.
EXAMPLE 4D
Benzoic acid, 4-[[2-butyl-5-[[1-[2-(dimethylamino)ethyl]-2,3-dihydro-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester, (E)
Mixture of E and Z-isomers; MS (CI) 487 (m). Analysis calculated for: C 29 H 34 N 4 O 3 .0.73 CH 3 OH: C, 70.02; H, 7.30; N, 10.99. Found: C, 70.25; H, 7.13; N, 10.59.
EXAMPLE 4E
1H-Indole-1-propanoic acid, 3-[[2-butyl-1-[[4 (methoxycarbonyl)phenyl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo, ethyl ester. (E)
MS (CI) 516 (m). Analysis calculated for C 30 H 33 N 3 O 5 .0.44 MeOH: C, 69.02; H, 6.61; N, 7.93. Found: C, 68.76; H, 6.33; N, 7.99.
EXAMPLE 4F
Benzoic acid, 4-[[2-butyl-5-[[1-[(4-chlorophenyl)methyl]-2,3-dihydro-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, (E)
MS (CI) 526 (m). Analysis calculated for C 31 H 28 N 3 O 3 Cl.0.2 H 2 O: C, 70.30; H, 5,40; N, 7.93. Found: C, 70.27; H, 5.45, N, 8.03.
EXAMPLE 4G
Benzoic acid. 4-[2-butyl-5-[[2,3-dihydro-1-(2-methoxy-2-oxoethoxy)-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester
By substituting compound from Example 2D with compound 2C in Example 4 and using methyl bromoacetate, the above target compound was obtained.
MS (CI) 504 (m). Analysis calculated for C 28 H 29 N 3 O 6 .0.5 H 2 O: C, 66.79; H, 5.80; N, 8.34. Found: C, 65.61; H, 5.90; N, 8.20.
EXAMPLE 4H
Benzoic acid, 4-[[2-butyl-5-[[1-(cyanomethyl)-2,3-dihydro-2-oxo-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester, (E)
Z-isomer; MS (CI) 455 (m) ; mp 193°-195° C. Analysis calculated for C 27 H 26 N 4 O 3 : C, 71.35; H, 5.77; N, 12.33. Found: C, 71.04; H, 5.71; N, 12.15.
E-isomer; MS (CI) 455 (m) ; mp 124°-127° C. Analysis calculated for C 27 H 26 N 4 O 3 : C, 71.35; H, 5.77, N, 12.33. Found: C, 71.04, H, 5.63, N, 12.11.
EXAMPLE 4I
Ethyl (Z)-(±)-2,3,dihydro-3-[[3-[[4-(methoxycarbonylphenyl]methyl]-2-propyl-3H-imidazol-4-yl]methylene]-4-methyl-2-oxo-α-propyl-1H-indole-1-acetat
By substituting compound from Example 2D with compound 1E in Example 4 and using ethyl 2-bromopentanoate, the title compound was obtained. MS (CI) 544 (m); mp 154°-156° C.
Analysis calculated for C 32 H 37 N 3 O 5 : C, 70.70; H, 6.86; N, 7.73. Found: C, 70.38; H, 6.93; N, 7.55.
EXAMPLE 4J
Methyl (Z)-2,3-dihydro-3-[[3-[[4-methoxycarbonylphenyl]methyl]-2-propyl-3H-imidazol-4-yl]methylene]-4 -methyl -2-oxo-1H-indole-1-acetate
By substituting compound from Example 2D with compound 1E in Example 4 and using methyl bromoacetate, the title compound was obtained. MS (CI) 488 (m); mp 228°-230° C.
Analysis calculated for C 28 H 29 N 3 O 5 .1.2 H 2 O: C, 66.05; H, 6.22; N, 8.27. Found: C, 65.85; H, 5.93; N, 7.97.
EXAMPLE 4K
Methyl 4-[[2-butyl-5-[(1-butyl-1,2-dihydro-2-oxo-3H-indol-3-yliden)methyl]-1H-imidazolyl]methyl]-3-chlorobenzoate
By substituting compound from Example 2D with compound 1A in Example 4, the above compound was obtained. MS (CI) 505 (m).
EXAMPLE 4L
Ethyl (Z)-3-[[2-butyl-3-[[4-(methoxycarbonyl)phenyl]methyl]-3H-imidazol-4-yl]methylene]-2,3-dihydro-7-methoxy-2-oxo-1H-indole-1-acetate
By substituting compound from Example 2D with compound 1H in Example 4, and using ethyl bromoacetate, the title compound was obtained.
MS (CI) 532, (m), mp 157°-158° C. Analysis calculated for C 30 H 33 N 3 O 6 .0.34 MeOH: C, 67.17; H, 6,38; N, 7.90. Found: C, 66.78; H, 6.15; N, 7.72.
The following compounds have been prepared by methods similar to those above:
4-[[2-butyl-5-[(1,2-dihydro-7-methyl-2-oxo-3H-indol-3-ylidenyl)methyl]-1H-imidazol-1-yl]methyl]benzoic acid
Methyl 4-[[5-[(1,2-dihydro-1-methyl-2-oxo-3H-indol-3-ylidenyl)methyl]-2-propyl-1H-imidazol-1yl]methyl]benzoate
Methyl 2,3-dihydro-3-[[3-[[4-(methoxycarbonyl) phenyl]methyl]-2-propyl-3H-imidazol-4-yl]methylene]-2-oxo-1H-indole-7-acetate
EXAMPLE 5
Benzoic acid, 4-[[2-butyl-5-[[2,3-dihydro-2-oxo-1-(1H-tetrazol-5-ylmethyl)-1H-indol-3-ylidene]methyl]-1H-imidazol-1-yl]methyl]-, methyl ester, (E)
A mixture of 0.5 g (1.1 mM) of the nitrile from Example 4H, NaN 3 (0.14 g, 2.2 mM) and 0.12 g (NH 4 Cl) in DMF (10 mL) was heated at 95° C. for 4.5 hours. DMF was distilled under vacuum and the residue was treated with water. The solution was adjusted to pH 2 when an orange colored solid precipitated. It was filtered, washed successively with water and ether, and finally air-dried to give 0.38 g of a solid. 1 H NMR indicate mostly Z-isomer. HPLC indicate a mixture of 82% (Z)- and 15% (E)-isomer. MS (CI) 498 (m). The filtrate was adjusted to pH 5 and the solid was filtered, washed with successively with water and ether, and air-dried to give 50 mg of a yellow solid. 1 HNMR idicate mostly E-isomer. HPLC indicate a mixture of 82.5% (E)- and 4.6% (Z)-isomer. MS (CI) 498 (m).
EXAMPLE 6
1H-Indole- 1-acetic acid, 3-[[2-butyl-1-[[4-(1H-tetrazol-5-yl)phenyl]methyl]-1H-imidazol-5yl]methylene]-2,3-dihydro-2-oxo-, methyl ester
A mixture of 3.58 g (6.5 mmol) of the compound from Example 14, oxindole (0.91 g, 6.8 mmol) and piperidine (0.1 g) in toluene (35 mL) was heated under reflux for 18 hours under N 2 . The reaction mixture was cooled and filtered to give a solid. The filtrate was evaporated to remove toluene. This residue was combined with the solid and chromatographed [CH 2 Cl 2 CH 2 Cl 2 /EtOAc(1:1)]to separate E-(2.1 g) and Z-isomer (1.2 g) of the desired product. 3-[[2-butyl-3-[[4-[2-(triphenylmethyl)-2H-tetrazol-5-yl]phenyl]methyl]-3H-imidazol-4-yl]methylene]-1,3-dihydro-2H-indol-2-one
A mixture of 0.45 g (0.67 mmol) of the above oxindole, CS 2 CO 3 (4.79 g, 14.7 mmol) and methyl bromoacetate ((0.11 g, 0.7 mmol) in DMF (10 mL) was stirred at room temperature for 2 hours. Upon usual work up and purification [chromatography, CH 2 Cl 2 /Hexane (10%) --CH 2 Cl 2 /EtOAc(20%)]gave 0.9 g of the target compound. Methyl 3-[[2-butyl-3-[[4-[2-(triphenylmethyl)-2H-tetrazol-5-yl]phenyl]methyl]-3H-imidazol-4-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetate
A solution of the above trityltetrazole compound (0.9 g) in MeOH (12 mL) was heated under reflux for 16 hours. The reaction mixture was cooled to 0° C. and filtered. The residue was washed with small volume of methanol and air-dried to give the tetrazole derivative (0.4 g). MS (CI) 498 (m) , mp 222°-231° C.
Analysis calculated for C 27 H 27 N 7 O 3 .0.6 H 2 O: C, 63.79; H, 5.59; N, 19.29. Found: C, 64.19; H, 5.42; N, 18.82.
EXAMPLE 6A
1H-Indole-1-acetic acid, 3-[[2-butyl-1-[[4-(1H-tetrazol-5-yl)phenyl]methyl]-1H-imidazol-5yl]methylene]-2,3-dihydro-2-oxo-, ethyl ester
The title compound was analogously prepared. (CI) 511 (m); mp 185°-188° C.
Analysis calculated for C 28 H 29 N 7 O 3 .0.63 H 2 .0.51 EtOAc; C, 63.55; H, 6.11; N, 17.24. Found: C, 63.54; H, 5.81; N, 17.23.
EXAMPLE 7
3-[[2-butyl-3-[[4-(1H-tetrazol-5-yl) phenyl]methyl]-3H-imidazol-4-yl]methyl ene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid
The compound from Example 6 was suspended in MeOH (8 mL) to which was added a solution of dilute NaOH (0.103 g in 1 mL H 2 O). The clear solution was stirred at room temperature for 2 hours. MeOH was removed, the residue was diluted with water, and the solution adjusted to pH 4. The precipitate was filtered, washed with small volume of water, and dried under vacuum at 80° C. for 3.5 hours. 1 H NMR indicate a 1:1 mixture of E- and Z-isomer of the desired product.
MS (CI) 484 (m), mp 212°-215° C. Analysis calculated for C 26 H 25 N 7 O 3 .0.74 H 2 O: C, 63.03; H, 5.19; N, 19.34. Found: C, 62.85; H, 5.37%; N, 19.73.
EXAMPLE 8
2(1H)-Isoquinolineacetic acid, 3,4-dihydro-4-[[1-[[4-(methoxycarbonyl)phenyl]methyl]-2-propyl-1H-imidazol-5-yl]methylene]-1,3-dioxo-, methyl ester, (Z)
A mixture of glycine methyl ester hydrochloride (0.77 g, 6.17 mmol), homophthalic anhydride (1.0 g, 6.17 mmol) and K 2 CO 3 (0.86 g) in toluene (60 mL) was heated under reflux with a Dean-Stark apparatus for 8 hours. The reaction mixture was cooled, filtered, and the residue was washed thoroughly with EtOAc. The filtrate and the washings were evaporated to give 1.15 g of a yellow solid. MS (EI) 233 (m). This was used as is for the next step.
A mixture of 0.75 g (2.62 mmol) of the aldehyde from Example 11B and 0.6 g (2.62 mmol) of the above-homophthalimide-derivative in toluene (50 mL) containing catalytic amount of piperidine was heated under reflux for 18 hours. Toluene was distilled under vacuum and the residue chromatographed (CH 2 Cl 2 /Acetone 2-7%) to give 0.9 g of a bright orange solid. 1H NMR indicate 95% of the Z-isomer. MS (CI) 502, (m).
Analysis calculated for C 28 H 27 N 3 O 6 : C, 67.06; H, 5.43; N, 8.58. Found: C, 67.07; H, 5.37; N, 8.22.
EXAMPLE 9
(Z)-3-[[3-[(4-carboxyphenyl)methyl]-2-propyl-3H-imidazol-4-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid
(E)-3-[[3-[(4-carboxyphenyl)methyl]-2-propyl -3H-imidazol-4-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetic acid
A solution of 0.26 g (1.36 mmol) of 2,3-dihydro-2-oxo-1H-indole-1-acetic acid (prepared by saponification of 2,3-dihydro-2-oxo-1H-indole-1-acetic acid, ethyl ester) and 0.37 g (1.36 mmol) of compound from Example 11C in (5 mL) of acetic acid containing 10 mg of β-alanine was refluxed for 18 hours. The solution was cooled and the precipitate was filtered. The residue was washed with hexane and subjected to fractional crystallization from isopropyl alcohol to give E - and Z - isomers. Z - isomer; orange sol id; mp 290°-291° C. (dec). MS (CI) 446 (m).
Analysis calculated for C 25 H 23 N 3 O 5 .0.53 H 2 O: C, 65.99; H, 5.33; N, 9.33. Found: C, 65.60; H, 4.74; N, 8.96.
E-isomer; yellow solid, mp 198°-200° C. MS (CI) 446 (m). Analysis calculated for C 25 H 23 N 3 O 5 .0.9 H 2 O: C, 65.04; H, 5.41; N, 9.10. Found: C, 64.88; H, 5.44, N, 9.06.
EXAMPLE 10
Benzoic acid, 4-[[2-butyl-5-[(2,3-dihydro-2-oxo-1H-indol-3-yl)methyl]-1H-imidazol-1-yl]methyl]-, methyl ester, (±)
A solution of (0.5 g) of the compound from Example 2E in AcOH (15 mL) containing Ra/Ni (0.5 g) was subjected to catalytic reduction. HOAc was distilled under high vacuum and the residue was taken up in EtOAc. The EtOAc solution was washed with NaHCO 3 followed by water, dried, and evaporated to yield an off-white foam. It was chromatographed (CH 2 Cl 2 /MeOH, 5-10%) to give 0.29 g of the desired title compound. MS (CI) 417 (m).
Analysis calculated for C 25 H 27 N 3 O 3 .0.5 H 2 O: C, 70.40; H, 6.62; N, 9.85. Found: C, 70.04; H, 6.47; N, 9.62.
Synthesis of the requisite 5-formyl-imidazole derivatives.
EXAMPLE 11
Ethyl 2-butyl-4-[[5-(formyl)-1H-imidazol-1-yl]methyl]benzoate was prepared according to the procedure described in U.S. Pat. No. 4,207,324.
2-Butyl-4-chloro-5-formyl-imidazole
A mixture of 2-butyl-4-chloro-5-hydroxymethylimidazole 20 g (0.1 mol) and MnO 2 (46.1 g, 0.53 mol) in THF (500 mL) was heated at reflux for 4 hours. The reaction mixture was cooled and filtered through a bed of celite and washed thoroughly with hot THF. The filtrate and the washings were concentrated under reduced pressure to give 18.7 g of a solid. It was chromatographed using CH 2 Cl 2 /MeOH (2%) as eluant to give 14 g of a solid; mp 95°-96° C.
A mixture of the above aldehyde (1.86 g, 0.01 mol) and CS 2 CO 3 (7.17 g, 0.02 mol) in DMF (20 mL) was stirred for 10 minutes. To this mixture was added a solution of (4-carbethoxy) benzylbromide (2.7 g, 0.011 mol) in DMF (10 mL) and the resulting mixture was stirred for 2 hours. DMF was distilled, the residue was treated with water, and the mixture was extracted with EtOAc. The EtOAc solution was washed with brine, dried, and evaporated. The residue was chromatographed (CH 2 Cl 2 /EtOAc, 10-15%) to give an oil (2.7 g). MS (CI) 345 (m).
Analysis calculated for C 18 H 21 ClN 2 O 3 : C, 61.98; H, 6.07; N, 8.03. Found: C, 61.65; H, 6.09; N, 7.84.
A solution of the above 4-chloro-imidazole derivative (1.18 g) in EtOH (75 mL) containing KOAc (0.33 g) was subjected to catalytic reduction in presence of 5% Pd-C to give the title compound as an oil (0.8 g). MS 314, (m).
The following compounds were prepared in an analogous manner.
EXAMPLE 11A
Methyl 2-butyl-4-[[5-(formyl)-1H-imidazol-1-yl]methyl]benzoate
EXAMPLE 11B
Methyl 2-propyl-4-[[5-(formyl)-1H-imidazol-1-yl]methyl]benzoate
EXAMPLE 11C
2-Propyl-4-[[5-(formyl)-1H-imidazol-1-yl]methyl]benzoic acid was obtained from 11B by saponification.
EXAMPLE 11D
Methyl 4-[[2-ethyl-5-(formyl)-4-methyl-1H-imidazol-1-yl]methyl]benzoate
Methyl 4-[[2-ethyl-4-methyl-1H-imidazol-1-yl]methyl]benzoate compound was prepared from 2-ethyl-4-methyl-imidazole and (4-carbmethoxy) benzylbromide in an analogous fashion as described in Example 11. A solution of the above imidazole (2.17 g, 8.14 mmol), NaOAc (1.17 g), 37 % HCHO (10 mn) , and AcOH (1.2 mn) was heated under reflux for 22 hours. The solution was evaporated under vacuo, and the residue was stirred with 10 mL of 20% NaOH solution for 2 hours. It was diluted with water and the solution was extracted with CH 2 Cl 2 . The extract was washed with water, dried, and evaporated to an oil. It was chromatographed (CH 2 Cl 2 /MeOH, 2-5%) to give 1.0 g of the desired hydroxymethyl compound as a foam. MS (CI 288 (m).
A solution of the above hydroxymethyl imidazole derivative (1.0 g) was oxidized with MnO 2 (1.5 g) in CH 2 Cl 2 (10 mL) as before. The product was purified by chromatography (CH 2 Cl 2 /MeOH, 2%) to give the title compound (0.73 g) as a highly viscous gum which crystallized on standing, MS (CI) 286 (m).
EXAMPLE 11E
2-Ethyl-4-[[5-(formyl)-1H-imidazol-1-yl]methyl]benzoic acid
A solution of the above ester from Example 11D in MeOH (4 mL) and 4N KOH (1.3 mL) was stirred at room temperature for 18 hours. MeOH was removed, the residue was treated with water, and the solution was adjusted to pH 5. It was extracted with EtOAc and the extract was dried and evaporated to give a pale yellow solid which was used as is for condensation with oxindole.
EXAMPLE 12
Ethyl 4-[[5-formyl-2-propyl-4-(1H-pyrrol-1-yl)-1H imidazol-1-1-yl]methyl]benzoate
Ethyl 4-amino-2-propylimidazole-5-carboxylate
A mixture of methyl propionimidate hydrochloride (4.8 g), ethyl 2-amino-2-cyanoacetate oxalate (4.0 g), anhydrous sodium acetate (9.1 g), and absolute ethanol (75 mL) was stirred at room temperature for 18 hours. Solids were removed by filtration and the filtrate was evaporated. The residue was partitioned between ethyl acetate and water. The ethyl acetate layer was washed with saturated NaCl, dried over MgSo 4 , and evaporated. Flash chromatography on silica gel, eluting with a gradient of dichloromethane-ethyl acetate (75:25) to ethyl acetate gives the title compound (2.7 g) as a pale yellow solid, mp 111°-114° C.; MS (DEI) 211 (m).
Ethyl 2-propyl-4-(1H-pyrrol-1-yl)imidazole-5-carboxylate
A solution of ethyl 4-amino-2-propylimidazole-5-carboxylate from above (9.34 g, 47 mmol) and sodium acetate (23.2 g) in acetic acid (100 mL) was heated to reflux and treated with 2,5-dimethoxy-tetrahydrofuran (6.75 mL, 52 mmol). The reaction was held at reflux for 30 minutes, then cooled back to room temperature with an ice bath. The majority of the acetic acid was evaporated under reduced pressure, then the residue was partitioned between ethyl acetate and 10% aqueous K 2 CO 3 (120 mL) each. The organic layer was dried over MgSO 4 and evaporated. The residue was purified by flash chromatography on silica gel, eluting with CH 2 Cl 2 -ethyl acetate (80:20). Evaporation of solvents gave a solid which was recrystallized from hexane/EtOAc (1:1) to give 7.4 g of the title compound, mp 134°-135° C.; MS (CI), 248 (m +1).
2-Propyl-5-(1H-pyrrol-1-yl)-1H-imidazole-4-methanol
Dissolved 11.77 mM (2.91 g) of the imidazole ester compound from above in 60 mL of dry THF followed by dropwise addition of 12 mL of 1 M lithium aluminum hydride in ether over a period of 20 minutes. The resulting reaction was allowed to stir overnight at room temperature. The reaction mixture was treated with 20 mL saturated aqueous ammonium sulfate resulting in a solid white precipitate which was filtered and washed well with ethyl acetate. The filtrate and the washings were then washed with water, brine, and then dried over MgSO 4 . Filtering off the drying agent and evaporating off the solvent gave a white solid which was crystallized from an 8:1 mixture of heptane and ethyl acetate to give 1.48 g (61.4%) of a white solid, mp 155°-158° C.; MS (CI) 205 (m).
2-propyl-5-(1H-pyrrol-1-yl)-1H-imidazole-4-carboxaldehyde
Dissolved 6.63 mM (1.36 g) of the imidazole alcohol compound in 60 mL of THF, followed by addition of 2.87 g (5 eq) of activated manganese dioxide while stirring vigorously. The resulting black suspension was heated to reflux for 5 hours then filtered warm through a pad of celite. The solids were washed well with ethyl acetate resulting in a yellow filtrate that when evaporated gave a beige solid. This crude solid was recrystallized from hexane/ethyl acetate (10:1) to give 0.74 g (54.9%) of a white solid, mp 118.5°-10° C.
Analysis calculated for C 11 H 13 N 3 O: C, 65.01; H, 6.45; N, 20.67. Found: C, 64.92; H, 6.29; N, 20.30. MS (CI) 203 (m).
By substituting the 5-formyl-imidazole compound in Example 11 with the above 5-formyl-imidazole and following the procedure described in Example 11, the title compound was obtained as an oil, MS (CI) 351 (m).
EXAMPLE 13
5-[4-(Bromomethyl)phenyl]-2-(triphenylmethyl)-2H-tetrazole
5-(4-Methylphenyl)-1H-tetrazole
A solution of 4-toluenitrile (52.09 g, 0.44 mol), NaN 3 (57.8 g 0.87 mol) and NH 4 Cl (47.62 g, 0.89 mol) in DMF (150 mL) was heated at 95° C. for 18 hours. The reaction mixture was cooled, diluted with water, and acidified with HCl. The solid was filtered, washed with water, and dried under vacuum at 70° C. for 4 hours to give the title compound; mp 243°-244° C.; MS (CI) 161 (m +1).
5-(4-Methylphenyl)-2-(triphenylmethyl)-2H-tetrazole
Tritylchloride (112.4 g, 0.4 mol) was added to a solution of the above tetrazole (68 g, 0.4 mol) and Et 3 N (61.4 g, 0.44 mol) in DMF (2500 mL) with stirring. The reaction mixture was stirred for 16 hours and filtered. The residue was thoroughly washed with DMF. The filtrate and the washings were evaporated under vacuum and the residue was taken up in large volume of EtOAc. The EtOAc solution was washed with water, dried, and evaporated to give 165 g of the desired compound; mp 172°-175° C.
5-[4-(Bromomethyl)phenyl]-2-(triphenylmethyl)-2H-tetrazole
A mixture of the above compound (100 g, 0.248 mol) and NBS (44.2 g, 0.24 mol) in CCl 4 (1 L) containing catalytic amount of VAZO-52 (0.5 g) was heated under reflux for 4 hours. Additional quantity of NBS (4.4 g) was added and the reaction mixture was heated for 45 minutes. It was filtered and the filtrate was evaporated to give an orange solid. It was recrystallized from EtOAc/Hexane (2:1) to give 68 g of the title compound as a white solid, mp 165°-172 ° C.
Analysis calculated for C 27 H 21 BrN 4 ; C, 67.37; H, 4.40; N, 11.64. Found: C, 66.90; H, 4.20; N, 11.13.
EXAMPLE 14
2-Butyl-5-chloro-3-[[4-[2-(triphenylmethyl)-2H-tetrazol-5-yl]phenyl]methyl]-3H-imidazole-4-carboxaldehyde
The bromomethyl derivative from Example 13 was used to alkylate 2-butyl-4-chloro-5-formyl-imidazole by following the procedure described in Example 11 to give the desired compound as a white solid (23 g); mp 154°-157° C., MS (CI), 587 (m -1);
Analysis calculated for C 35 H 32 N 6 ClO; C, 71.48; H, 5.48; N, 14.29. Found: C, 71.36; H, 5.21; N, 14.15.
2-Butyl-3-[[4-[2-(triphenylmethyl)-2H-tetrazol-5-yl]phenyl]methyl]-3H-imidazole-4-carboxaldehyde
17.3 g of the chloro compound was reduced in presence of 5% Pd-C as described in Example 11. The crude material was purified via chromatography [CH 2 Cl 2 /Hexane (20%) CH 2 Cl 2 /EtOAc(20%)] to give the desired material; mp 176°-177° C.; MS (CI), 554 (m);
Analysis calculated for C 35 H 34 N 6 O; C, 75.92; H, 6.01; N, 15.18. Found: C, 75.83; H, 5.97; N, 15.26.
EXAMPLE 15
The oxindoles were either commercially available or were prepared by following known literature methods.
1,3-Dihydro-1-propyl-2H-indol-2-one (Walker, et al, J Med Chem 1970;13:983-85).
2,3-Dihydro-N-methyl-2-oxo-1H-indole-1-carboxamide, mp 159°-162° C.
2,3-Dihydro-2-oxo-1H-indole-7-acetic acid, ethyl ester, mp 145°-146° C.
1,3-Dihydro-1-methyl-2H-indol-2-one.
1,3-Dihydro-1-(1-methylethyl)-2H-indol-2-one; waxy solid.
Analysis calculated for C 11 H 13 NO: C, 75.40; H, 7.48; N, 7.99. Found: C, 75.60; H, 7.46; N, 7.45. (Andreani, et al, Fffarmaco Ed Sci 1977;32:703-05).
1-Hydroxyoxindole; mp 198°-202° C. prepare by the literature procedure (Kende AS, Thurston J, Syn Comm 1990;20:2133).
2,3-Dihydro-2-oxo-1H-indole-1-acetic acid, ethyl ester.
EXAMPLE 16
(Z) Ethyl 3-[[2-butyl-1-[[4-(methoxycarbonyl)phenyl]methyl]-1H-imidazol-5-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetate
A mixture of 1 g of 2-butyl imidazole-4-carboxaldehyde and 2,3-dihydro-2-oxo-1H-indole-7-acetic acid, ethyl ester (1.5 g) in toluene (20 mL) containing 0.6 mL of piperidine was heated under reflux for 18 hours. Toluene was distilled under vacuum and the residue was crystallized from hexane/ethyl acetate to give 2.0 g of the desired product; mp 118°-119° C., MS (CI), 354 (m);
Analysis calculated for C 20 H 23 N 3 O 3 ; C, 667.97; H, 6.56; N, 11.89. Found: C, 68.15; H, 6.62; N, 12.07.
BOC anhydride (1.9 g, 8.7 mmol) was added to a solution of the above imidazole product (2.0 g, 5.6 mmol) and Et 3 N (6.2 mmol) in CH 2 Cl 2 (20 mL) and the reaction mixture was stirred at room temperature for 16 hours. The solution was washed with water, brine, and dried over anhydride MgSO 4 , and stripped to give a solid which was recrystallized from hexane/EtOAc to give a yellow solid. MS (CI) , 454 (m);
Analysis calculated for C 25 H 31 N 3 O 5 .0.4 H 2 O; C, 65.17; H, 6.96; N, 9.12. Found: C, 65.31; H, 6.79; N, 8.72.
To a solution of triflic anhydride (0.74 mL, 4.4 mmol) in CH 2 Cl 2 (20 mL) at -78° C. was added dropwise a solution of 4-(carbomethoxy)benzylalcohol (0.7 g, 4.2 mmol) and diisopropyl ethylamine (0.8 mL, 4.6 mmol) in CH 2 Cl 2 (10 mL) under nitrogen atmosphere. The mixture was stirred for additional 15 minutes followed by the addition of a solution of the above BOC imidazole derivative (1.9 g, 4.2 mmol) in CH 2 Cl 2 (10 mL). The solution was allowed to warm to room temperature and stirred for 16 hours. The solution was diluted with CH 2 Cl 2 and washed with water, brine, dried over anhydrous MgSO 4 , and stripped. The residue was dissolved in CH 2 Cl 2 and filtered to give 0.43 g of the title product; mp 207°-209° C.; MS (CI) , 502 (m): The filtrate was chromatographed (EtOAc/CH 2 Cl 2 (4:1)--EtOAc) to give 0.9 g of additional product. This was identical to the compound from Example 2A.
EXAMPLE 17
Ethyl 3-[[2-butyl-1-[[4-[1H-tetrazol-5-yl]phenyl]methyl]-1H-imidazol-5-yl]methylene]2,.3-dihydro-2-oxo-1H-indole-1-acetate
A mixture of 2.0 g of 5-[4-(bromomethyl)phenyl]-2-(triphenylmethyl)-2H-tetrazole from Example 13 and 1N NaOH (5 mL) in THF (20 mL) was stirred for 24 hours. The solvent was evaporated and the aqueous solution extracted with EtOAc. The organic layer was washed with water, dried, and evaporated to give 1.8 g of 5-[4-(hydroxymethyl)phenyl]-2-(triphenylmethyl)-2H-tetrazole which was used as is for the next step; MS (EI), 418 (m).
By following the procedure described in Example 16 and using the above 5-[4-(hydroxymethyl) phenyl]-2-(triphenylmethyl)-2H-tetrazole in place of 4-(carbomethoxy)benzyl alcohol, the compound ethyl 3-[[2-butyl-3-[[4-[2-(triphenylmethyl)-2H-tetrazol-5-yl]phenyl]methyl]-3H-imidazol-4-yl]methylene]-2,3-dihydro-2-oxo-1H-indole-1-acetate was obtained.
To a solution of triflic anhydride (0.74 mL, 4.4 mmol) in CH 2 Cl 2 (20 mL) at -78° C. was added dropwise a solution of 5-[4-(hydroxymethyl)phenyl]-2-(triphenylmethyl)-2H-tetrazole (1.75 g, 4.2 mmol) and diisopropyl ethylamine (0.8 mL, 4.6 mmol) in C- 2 Cl 2 (10 mL) under nitrogen atmosphere. The mixture was stirred for additional 15 minutes followed by the addition of a solution of the BOC imidazole derivative from Example 16 (1.9 g, 4.2 mmol) in CH 2 Cl 2 (10 mL). The solution was allowed to warm to room temperature and stirred for 16 hours. The solution was diluted with CH 2 Cl 2 and washed with water, brine, dried over anhydrous MgSO 4 , and stripped. The residue was dissolved in CH 2 Cl 2 and filtered to give 1.7 g of the title product; MS (FAB), 755 (m).
A solution of the above material (1.7 g) in CH 30 H (15 mL) and citric acid (10%, 5 mL) was heated at reflux for 16 hours. The solution was evaporated and the CH 3 OH solution was diluted with water and extracted with hexane. The aqueous solution was finally extracted with EtOAc and the extract was washed with water, dried over MgSO 4 , stripped, and the residue chromatographed (CH 2 Cl 2 /MeOH; 9:1) to give 0.8 g of the title compound; MS (FAB), 512 (m +1);
Analysis calculated for C 28 H 29 N 7 O 3 .0.51 EtOAc.0.63 H 2 O; C, 63.55; H, 6.11; N, 17.24. Found: C, 63.54; H, 5.81; N, 17.23. | This invention relates to novel substituted imidazole and triazole derivatives which antagonize the binding of angiotensin II to its receptors. The compounds are useful in the treatment of hypertension, heart failure, glaucoma, and hyperaldosteronism. Methods of making the compounds, novel intermediates useful in the preparation of the compounds, pharmaceutical compositions containing the compounds, and methods of using them are also covered. | 2 |
CROSS-REFERENCED APPLICATIONS
[0001] The present application claims priority of French Patent Application No. 02 11221, filed on Sep. 11, 2002.
[0002] The present application claims priority of U.S. provisional patent application serial No. 60/448,900, filed on Feb. 19, 2003, entitled “Cerammable Mineral Glass, Preparation of Glass-Ceramic Articles, Said Articles,” the content of which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0003] The present invention relates to:
[0004] novel mineral glasses which are cerammable;
[0005] use of said glasses or of mineral fillers, which are precursors of such glasses for preparing glass-ceramic articles. In this, said cerammable mineral glasses of the invention are particularly interesting. They enable quality glass-ceramics to be obtained under efficient process conditions;
[0006] the preparation of glass-ceramic articles, from such glasses or mineral fillers, which are precursors of such glasses;
[0007] said glass-ceramic articles.
BACKGROUND OF THE INVENTION
[0008] The present invention is related to United States Patent No. 5,070,045, which is incorporated herein in its entirety. The present invention provides an improvement of the teaching of this reference.
[0009] The present invention is generally related to the art of preparation of glass-ceramic articles. It is well-known that this preparation has three main process steps:
[0010] melting a mineral glass or melting a mineral filler, which is a precursor of such a glass, containing an effective amount of nucleation agent(s). Mention can in general be made of a first step of melting vitrifiable starting materials containing said nucleation agent(s);
[0011] cooling and shaping the molten glass obtained, cooling to a temperature which is lower than the conversion domain (interval) of said glass;
[0012] crystallizing or ceramming the shaped glass by an appropriate heat treatment. In general, this third and last step of the process is carried out in two phases. The shaped glass (the glass article obtained after the second step of the process) is first of all brought to a temperature which is slightly higher than the conversion domain of said glass, so as to generate nucleation grains within it. The temperature is then increased up to a value which is high enough in order that the growth of the crystals on the grains be produced.
[0013] During the second of said steps (cooling and shaping of the melted glass), it is desired to prevent any devitrification, any crystallization, which is synonymous with appearance of faults in the glass prepared.
[0014] On the contrary, during the third of said steps (ceramming), it is desired to crystallize said glass in a controlled manner in order to convert it into a glass-ceramic.
[0015] The characteristics of devitrification of the glass, in particular its liquidus viscosity, are critical during the second of said steps. It is known that a risk is taken of generating defective products—glass having devitrification faults, within its mass and/or on the surface—insofar as the viscosity during shaping of the glass in question is higher than its liquidus viscosity. Each shaping process necessitates that the glass be conditioned in a given viscosity range. A glass having a higher liquidus viscosity enables an easier shaping. The tolerance with respect to the existence of cold points is greater. This is all the more true because the volume of glass concerned is greater.
[0016] In the case of the glass-ceramic, the objects formed (cooktop plates, fire protection windows . . . ) are in general of quite large dimensions, and, whatever the shaping technique implemented for the shaping of the precursor glasses is (lamination, pressing or shaping from gobs, as described in the patent application FR-A-2,735,562), an increase in the liquidus viscosity of said glasses is an appreciable advantage, in terms of lowering the percentage of losses (of defective products, due to the devitrification) and of flexibility of shaping.
[0017] The present invention provides, as indicated above, an improvement of the teaching of the patent U.S. Pat No. 5,070,045 (a teaching according to which, from a single glass of the type specified, glass-ceramics can be obtained rapidly, the predominant crystalline phase of which is a solid solution of β-quartz or of β-spodumene, and the linear thermal expansion coefficient of which is very low, even zero), an improvement which aims to minimize the defective products mentioned above. Said improvement is based on the incorporation of novel mineral glasses (or novel mineral fillers), which possess a maximum liquidus viscosity. Within them, much less faults are generated during said second step (of conjugated cooling and shaping). In an entirely surprising way, the present invention offers a command of said second step, which is much greater than that which the prior art offered, without the third step, of ceramming, being disturbed by it.
[0018] Said novel glasses of the invention can be converted into glass-ceramics in a short time (less than two hours), in deforming very little, just as those described in the patent U.S. Pat No. 5,070,045. They possess, with respect to said glasses of said US patent, a liquidus viscosity which is significantly increased.
[0019] The following can be specified with reference to the prior art.
[0020] For many years, with reference to the third step of ceramming, and only with reference to said third step, the importance is known of incorporating, in combination, the nucleation agents TiO 2 and ZrO 2 . On this subject, reference can be made to the article by D. R. Stewart entitled “TiO 2 and ZrO 2 as nucleants in a lithia aluminosilicate glass-ceramic” (pages 83-90 of “Advances in Nucleation and Crystallization in Glasses. Edited by L. L. Hench and S. W. Freiman. American Ceramic Society, Columbus, Ohio, 1971”). Said article explains the interest in incorporating said nucleating agents, TiO 2 and ZrO 2 , in a molar ratio,
R ′ = TiO 2 ZrO 2 ,
[0021] equal to 2. That is, for this value of said ratio, that the rate of conversion of the glass into glass-ceramic is the fastest and that the average size of the crystals is the lowest, i.e. that the best transparency of the glass-ceramic is obtained. These conclusions were recalled recently by G. H. Beall and L. R. Pinckney in an article entitled “Nanophase Glass-Ceramics”, appearing in J. Am. Ceram. Soc., 82 [1], 5-16 (1999).
[0022] In the patent U.S. Pat No. 5,070,045, the preparation, under advantageous conditions, notably in terms of rapidity, of glass-ceramic articles, is thus described. The cerammable glasses which are the starting materials, have the composition by weight below (%):
[0023] SiO 2 65-70
[0024] Al 2 O 3 18-19.8
[0025] Li 2 O 2.5-3.8
[0026] MgO 0.55-1.5
[0027] ZnO 1.2-2.8
[0028] BaO 0-1.4
[0029] SrO 0-1.4
[0030] with BaO+SrO 0.4-1.4
[0031] with MgO+BaO+SrO 1.1-2.3
[0032] As 2 O 3 0-1.5
[0033] Sb 2 O 3 0-1.5
[0034] with As 2 O 3 +Sb 2 O 3 0.5-1.5
[0035] Na 2 O 0-<1
[0036] K 2 O 0-<1
[0037] with Na 2 O+K 2 O 0-<1
[0038] with
2.8 Li 2 O + 1.2 ZnO 5.2 MgO > 1.8
[0039] TiO 2 1.8-3.2
[0040] ZrO 2 1-2.5.
[0041] Said glasses have a liquidus viscosity which is greater than 700 Pa·s (certainly greater than or equal to 600 Pa·s) and can be thermally crystallized into a glass-ceramic having a predominant crystalline phase of which is a solid solution of β-quartz or β-spodumene, and a coefficient of linear thermal expansion (20°-700° C.) of 0±3×10 −7 K −1 .
[0042] Said glasses contain TiO 2 and ZrO 2 , as nucleation agents, which are active in the third step of ceramming set forth above (specified in said US patent), in the amounts mentioned above. With reference to Tables 1 and 2 of said US patent, it is noted that the weight ratio
R = TiO 2 ZrO 2
( molar ratio R ′ = TiO 2 ZrO 2 ) ,
[0043] is at the maximum 1.9 (2.97) (Example 4).
[0044] In this US patent, no teaching is provided anyway on any incidence of said weight ratio (molar ratio) in the implementation of the second step of cooling and shaping set forth above (also specified in said US patent).
[0045] In such a context, the inventors have established that, surprisingly, in having said weight ratio
R = TiO 2 ZrO 2
[0046] between 2.2 and 4.5, the yield of said second step of cooling and shaping is considerably improved without affecting in a notable way the implementation of the third step of ceramming.
SUMMARY OF THE INVENTION
[0047] According one aspect, the present invention thus provides a mineral glasse having a composition by weight (expressed in percentages of oxides), consisting essentially of:
[0048] SiO 2 65-70
[0049] Al 2 O 3 18-20.5
[0050] Li 2 O 2.5-3.8
[0051] MgO 0.55-1.5
[0052] ZnO 1.2-2.8
[0053] BaO 0-1.4
[0054] SrO 0-1.4
[0055] with BaO+SrO 0.4-1.4
[0056] with MgO+BaO+SrO 1.1-2.3
[0057] Na 2 O 0-<1
[0058] K 2 O 0-<1
[0059] with Na 2 O+K 2 O 0-<1
[0060] with
2.8 Li 2 O + 1.2 ZnO 5.2 MgO > 1.8
[0061] TiO 2 1.8-3.5
[0062] ZrO 2 0.8-2.5
[0063] with
2.2 < TiO 2 ZrO 2 < 4.5 ,
[0064] and, optionally, an effective, non-excess amount of at least one fining agent.
[0065] In a second aspect of the invention, it is provided a glass-ceramic article made of the mineral glass described supra. Depending on the ceramming schedule, the glass-ceramic material can be prepared to have, inter alia, β-quartz or β-spodumene as the predominant crystalline phase.
[0066] In a third aspect, accordingly, the present invention provides processes for making such glass-ceramic articles.
DETAILED DESCRIPTION OF THE INVENTION
[0067] Said mineral glasses of the invention are virtually glasses according to the patent U.S. Pat No. 5,070,045. Reference can be made, as already indicated, to the teaching of this US patent, in order notably to have precisions on the respective incorporation amounts of each one of the constituent elements (of said glasses) listed above.
[0068] With reference to the amount of incorporation of Al 2 O 3 , it is noted that within the glasses of the invention, it has proved to be possible, even advantageous, that it be greater than 19.8%. This value of 19.8% was the critical high value given in the patent U.S. Pat No. 5,070,045. In incorporating more Al 2 O 3 within the glasses of the invention, glass-ceramics have been obtained from said glasses, which have a better transparency.
[0069] Characteristically, in the composition by weight set forth above of the glasses of the invention, there is:
[0070] TiO 2 1.8-3.5
[0071] ZrO 2 0.8-2.5, with
2.2 < R = TiO 2 ZrO 2 < 4.5 .
[0072] As already indicated, the inventors realized, with reference to the second step of obtaining a glass which is shaped in the preparation of a glass-ceramic, the importance of having said weight ratio
R = TiO 2 ZrO 2 > 2.2 .
[0073] The glass obtained exhibits an interesting liquidus temperature, which is 50 to 100° C. lower than that of the glasses according to the patent U.S. Pat No. 5,070,045. The viscosity of the novel glasses of the invention being comparable to that of the glasses according to said patent U.S. Pat No. 5,070,045, the gain in the liquidus viscosity is significant.
[0074] Said weight ratio,
R = TiO 2 ZrO 2 ,
[0075] is kept at less than 4.5, since, over this, it is difficult to obtain glass-ceramics, the predominant crystalline phase of which is a solid solution of β-quartz, which are transparent. They become opalescent.
[0076] According to an advantageous variant, said weight ratio R is between 2.3 and 4.5.
[0077] The mineral glasses of the invention contain, advantageously, an effective, non-excess amount of at least one fining agent. The person skilled in the art knows perfectly well how to manage the incorporation of this type of compound within a mineral glass. In general, it is in fact incorporated at less than 2% by weight of this type of compound within the glasses of the invention.
[0078] As an illustration, and in a manner which is in no way limiting, an indication is made that the mineral glasses of the invention can also contain As 2 O 3 and/or Sb 2 O 3 as fining agents, as do the glasses according to the patent U.S. Pat No. 5,070,045, in the amounts indicated in said US patent, namely:
[0079] As 2 O 3 0-1.5
[0080] Sb 2 O 3 0-1.5
[0081] with As 2 O 3 +Sb 2 O 3 0.5-1.5 (% by weight).
[0082] Said mineral glasses of the invention can, in the same manner, contain other compounds such as SnO 2 , CeO 2 and Cl, as fining agents.
[0083] The mineral glasses of the invention can be colored or non-colored.
[0084] In order that they display a real coloration, they contain, in addition to the constituent elements listed above, an effective amount of at least one coloring agent. Said coloring agent(s) is (are) in general selected from CoO, Cr 2 O 3 , Fe 2 O 3 , MnO 2 , NiO, V 2 O 5 , CeO 2 (and their mixtures).
[0085] As colored mineral glasses of the invention, those are more particularly preferred which have the composition by weight indicated above with, in addition, from 0.03 (advantageously 0.05) to 1% by weight of V 2 O 5 and the condition below:
3.8%≦TiO 2 +ZrO 2 +5V 2 O 5 <6%.
[0086] Articles, notably transparent, black glass-ceramic articles, the main crystalline phase of which is β-quartz, can be obtained from such glasses of the invention.
[0087] It was observed that within such glasses of the invention, vanadium oxide has a coloring effect which is more marked than within the glasses according to the patent U.S. Pat No. 5,070,045 and, that consequently, lower amounts prove a priori to be sufficient to obtain an equivalent coloration.
[0088] Without containing an effective amount of coloring agent(s), as specified above, glasses of the invention can have a slight coloration, due to the presence within them of a certain type of impurity(ies).
[0089] The glasses of the invention, which do not contain such an effective amount of coloring agent(s) (coloring agent(s) which is (are) added on purpose in their composition) advantageously have a content of alumina (Al 2 O 3 ) of between 19.8 and 20.5% and a content of zirconium oxide (ZrO 2 ) of between 1.2 and 2.5%. With such glasses, very transparent glass-ceramics have been obtained, which are without opalescence.
[0090] Transparent, colorless or opalescent glass-ceramic articles, even opaque, colorless glass-ceramic articles, the main crystalline phases of which are β-quartz or β-spodumene, respectively, can be obtained from non-colored glasses of the invention.
[0091] In the same way, transparent, colored or opalescent glass-ceramic articles, even opaque, colored glass-ceramic articles, the main crystalline phase of which are β-quartz or β-spodumene, respectively, can be obtained from colored glasses of the invention.
[0092] In addition to the essential and optional constituents set forth above, the mineral glasses of the invention can contain other constituents. Obviously, they contain such other constituents only in a limited amount (generally of less than 2% by weight), only in an amount which does not jeopardize the characteristics of said glasses of the invention. It is thus for example in no way excluded that the glasses of the invention contain P 2 O 5 and/or B 2 O 3 .
[0093] According to its second object, the present invention relates to the use of the mineral glasses above for the preparation of glass-ceramic articles. In an entirely logical way, said second object covers the use of fillers, which are precursors of such mineral glasses of the invention, for the preparation of glass-ceramic articles. In fact, according to the exact method of implementation of this preparation, the basic glass is isolated or not.
[0094] Said preparation of glass-ceramic articles, which constitutes the third object of the present invention, is implemented (almost) as described in the patent U.S. Pat No. 5,070,045, with the original starting material described above (the composition of which, which is characterized mainly by
R = TiO 2 ZrO 2
[0095] of between 2.2 and 4.5, is given above).
[0096] Thus, in order to prepare a glass-ceramic article containing a solid solution of β-quartz as predominant crystalline phase, the steps below are essentially carried out:
[0097] a) melting a glass as described above or melting a filler, a precursor of such a glass;
[0098] b) cooling the melted glass obtained to a temperature of lower than its conversion interval and simultaneously shaping it into the shape of the final article sought after;
[0099] c) increasing the temperature of the glass shape obtained, at the rate of 50 to 80° C./minute up to a temperature in the range 670-800° C.;
[0100] d) keeping said glass article within this temperature range between 670 and 800° C., for 15 to 25 minutes, in order to develop grains or nuclei within it;
[0101] e) increasing the temperature of said glass article, which is now nucleated, at a rate sufficient, in order to bring it, in 15-30 minutes, into the temperature interval of 900-980° C. (it proved to be possible, even advantageous, to increase said temperature up to 980° C.);
[0102] f) keeping said nucleated glass article in this temperature interval of 900-980° C., for 10 to 25 minutes, so as to make crystals of solid solution of β-quartz grow on these grains or nuclei;
[0103] g) rapidly cooling the crystallized article to ambient temperature.
[0104] Without incorporating an effective amount of at least one coloring agent in the composition of the initial glass (of the initial filler), and in the absence of colorant impurety(ies), the glass-ceramic article, obtained by the preparative process above, is colorless.
[0105] For the preparation of a glass-ceramic article containing a solid solution of β-spodumene as predominant crystalline phase, steps a) to g), clarified above, with a different temperature interval of 1,050-1,200° C. (instead of 900-980° C.) for the steps e) and f), are carried out in essentially the same manner.
[0106] The ceramming, carried out at a higher temperature, leads to the conversion of the transparent crystalline phase of solid solution of β-quartz (mainly) into another crystalline phase, derived from silica: a crystalline phase of solid solution of β-spodumene (mainly), which confers to the material an opalescent, white appearance, even an opaque appearance. The white color of said material, which is more or less opaque, can be sought after in specific domains of application.
[0107] For the preparation of a colored glass-ceramic article, containing a solution of β-quartz or of β-spodumene as predominant crystalline phase, the processes specified above are implemented, in incorporating, in step a), an effective amount of at least one coloring agent. It is recalled:
[0108] that the coloring agent(s) being incorporated is (are) generally selected from CoO, Cr 2 O 3 , Fe 2 O 3 , MnO2, NiO, V 2 O 5 , Ce 2 O (and the mixtures of these oxides);
[0109] that 0.03 to 1% (very advantageously 0.05 to 1%) by weight of V 2 O 5 is advantageously incorporated with the condition below: 3.8%≦TiO 2 +ZrO 2 +5V 2 O 5 ≦6%.
[0110] Steps b) to f) of the processes above, of obtaining a glass-ceramic article, are advantageously carried out in 2 hours at the maximum, and in about 1 hour in a particularly preferred manner.
[0111] According to its last object, the present invention relates to the glass-ceramic articles, which are obtainable according to the processes specified above, from mineral glasses (or mineral fillers, which are precursors of such glasses) which are constituents of the first object of said invention. The glass-ceramic of said articles has the composition indicated above for said mineral glasses. Such articles can notably consist of cooktop plates, which are adapted to different types of cooking (resistant, inductive, halogen heating), of cookware, which are also adapted to different types of cooking, to microwave oven bottom trays, woodstove windows, fire protection doors, fire protection windows. This list is obviously not limitative.
[0112] The invention is now illustrated by the Examples below. More specifically, Examples 1 to 4 and 4′ illustrate said invention, and the importance of the invention emerges from the consideration of Examples A, B and C. Said Examples A and B illustrate the prior art (R≦2) whereas said Example C illustrates a specific case wherein R>4.5
( R = TiO 2 ZrO 2 ; weight ratio ) .
Examples A, B, C, 1 to 4
[0113] Table 1 below indicates, in its first part, the compositions by weight of the glasses in question and their liquidus characteristics; in its second part, the characteristics of glass-ceramics obtained from said glasses; said glass-ceramics containing a solution of β-quartz as predominant crystalline phase.
[0114] For each example, an indication is made, in said Table 1, of the weight ratios
( R = TiO 2 ZrO 2 )
[0115] and molar ratios
( R ′ = TiO 2 ZrO 2 ) .
[0116] It is noted that, for the glasses of the invention, there is an R′ value which is significantly greater than 3, even though a ratio of 2 was recommended in the article by D. R. Stewart mentioned supra, and as regards the glasses exemplified in the patent U.S. Pat No. 5,070,045, said ratio R′ is of the order of 2.4.
[0117] The glasses are prepared in a usual manner from oxides and/or from compounds which are easily decomposable, such as nitrates or carbonates. The starting materials are mixed in order to obtain a homogeneous mixture. About 1,000 g, placed in a platinum crucible, are molten in an electric oven for 10 hours at 1,650° C. The melted glass is then poured onto a table and is rolled to a thickness of about 6 mm. It is then re-heated for 1 hour at 650° C., and then cerammed according to the following program:
[0118] rapid rise to 670° C.,
[0119] rise from 670 to 800° C. (nucleation interval) in 24 minutes,
[0120] rise, over 20 minutes, from 800 to 900° C.,
[0121] upkeep for 15 minutes between 900 and 980° C. (growth interval),
[0122] rapid cooling.
[0123] The liquidus temperatures were determined from small amounts of glass (a few grams), re-molten in platinum crucibles, and then held for 17 hours at the temperature studied before being tempered in air. The liquidus temperature is the lowest plateau temperature after which no crystals are observed.
[0124] The transmissions were measured on polished samples of 3 mm thickness. The measurement of visible transmission was made with the illuminant C, at a rate of a measurement point every nm, between 360 and 830 nm.
TABLE 1 Example Example Example Example A B C 1 2 3 4 1. Composition (% by weight) SiO 2 68.8 67.6 68.5 68.4 68.5 67.6 67.4 Al 2 O 3 18.95 19.85 18.95 18.95 18.95 19.75 20 Li 2 O 3.45 3.45 3.45 3.45 3.45 3.45 3.45 MgO 1.2 1.22 1.2 1.2 1.2 1.2 1.2 ZnO 1.62 1.66 1.62 1.62 1.62 1.62 1.62 BaO 0.8 0.8 0.8 0.8 0.8 0.8 0.8 MgO + BaO + SrO 2 2.02 2 2 2 2 2 As 2 O 3 0.5 0.79 0.8 0.8 0.8 0.8 0.8 Sb 2 O 3 As 2 O 3 + Sb 2 O 3 0.5 0.79 0.8 0.8 0.8 0.8 0.8 Na 2 O 0.15 0.17 0.15 0.15 0.15 0.15 0.17 K 2 O 0.2 0.19 0.2 0.2 0.2 0.2 0.19 Na 2 O + K 2 O 0.35 0.36 0.35 0.35 0.35 0.35 0.36 (2.8Li 2 O + 1.86 1.84 1.86 1.86 1.86 1.86 1.86 1.2ZnO)/5.2MgO TiO 2 2.6 2.6 3.8 3.1 3.3 3.1 3.1 ZrO 2 1.7 1.68 0.5 1.3 1 1.3 1.3 R = TiO 2 /ZrO 2 1.53 1.55 7.6 2.38 3.3 2.38 2.38 (weight ratio) R′ = 2.4 2.4 11.7 3.6 5.1 3.7 3.7 TiO 2 /ZrO 2 (molar ratio) V 2 O 5 0.22 0.02 0.1 0.09 0.1 2. Liquidus 1,350° C. 1,350° C. > 30,000 P 1,300° C. 1,250° C. 1,300° C. 1,300° C. 6,000 P 6,000 P 10,000 P 30,000 P 10,000 P 10,000 P 3. Appearance transparent transparent Strongly transparent transparent transparent transparent after ceramming black color practically opalescent black color black color black color practically colorless black colorless color 4. Properties after ceramming: CTE (25-700° C.) −1 × 10 −7 K −1 −1 × 10 −7 K −1 −0.3 × 10 −7 K −1 0.2 × 10 −7 K −1 −0.1 × 10 −7 K −1 Visible 5.65 4 2.3 4.5 transmission Transmission at 71.9 70.1 71.3 72.9 1,000 nm Transmission at 79.8 82.5 82.9 82.5 2,000 nm
Example 4′
[0125] Glass of Example 4 underwent the following treatment:
[0126] rapid rise to 670° C.,
[0127] rise from 670 to 800° C. (nucleation interval) in 20 minutes,
[0128] rise in 30 minutes to 1,070° C.,
[0129] upkeep for 30 minutes at 1,070° C.,
[0130] rapid cooling.
[0131] The resulting glass-ceramic contains β-spodumene as main phase. It has a white appearance, slightly translucent. Its dilation is of 8×10 −7 K −1 (20-700° C.). | The present invention relates to novel mineral glasses which are cerammable and which have a composition, expressed in percentages by weight of oxides, consisting essentially of: SiO 2 65-70; Al 2 O 3 18-20.5; Li 2 O 2.5-3.8; MgO 0.55-1.5; ZnO 1.2-2.8; BaO 0-1.4; SrO 0-1.4; with BaO+SrO 0.4-1.4; with MgO+BaO+SrO 1.1-2.3; Na 2 O 0-<1; K 2 O 0-<1; with Na 2 O+K 2 O 0-<1;
with 2.8 Li 2 O + 1.2 ZnO 5.2 MgO > 1.8 ;
TiO 2 1.8-3.5; ZrO 2 0.8-2.5;
with 2.2 < TiO 2 ZrO 2 < 4.5 ; preferably 2.3 < TiO 2 ZrO 2 < 4.5 ;
and, optionally, an effective, non-excess amount of at least one fining agent. The present invention also relates to glass-ceramic articles made from such glass as well as processes for making such glass-ceramic articles. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to valves, and more particularly, but not exclusively, to valves for use in filter presses.
2. Description of the Prior Art
In a filter press, the filtrate collected at the individual filter plates may be guided out into a collecting channel through a one-way valve. A valve of this kind permits only free outlet or shut-off (open filtration). However, for reasons of hygiene or for reasons of safety (for example due to the danger of an explosion) there are many products which cannot be subjected to open filtration. In this case the filtrate is led away through a collecting channel which is located within the filter press fittings and extends through them. This "closed filtration" has the disadvantage that the condition of the filtrate or that of the wash liquid in the next stage of the process cannot be checked at the individual plates. Therefore if a fault or a blockage occurs, it is sometimes necessary to take the whole press out of operation, or to re-filter the product.
For this reason, multi-way valves have been proposed for use in open or closed filtration processes as required, according to the nature of a product. Even in the case of closed filtration processes, checks may be made or specimens may be taken at individual filter plates. If lack of tightness occurs because of damaged filter cloths, it is possible to prevent the further outlet of impure filtrate at the individual plates by shutting off the valve. The previously proposed filtrate run-off valves usually operate on the throughput member principle, in which a throughput member with different bores according to the function of the valve is arranged so as to be rotatable about its longitudinal axis in a one-part or multi-part casing. However, for effective sealing, the throughput members have to be ground in, in a conical casing. Therefore exchange of individual parts is not possible. For good sealing the throughput members must move stiffly, and they can then be actuated only with difficulty. On the other hand, ease of movement mostly leads to lack of tight sealing.
Further, it is not possible to provide sufficiently large bores in a throughput member without disadvantageous change of the diameter of the throughput member and therefore of the overall height of the whole valve. However, since generally the valve forms the narrowest part of the whole filter run-off system, relatively large bores are advisable. The problem of insufficiently large bore cross-sections arises more particularly in the case of multi-way valves, because in such valves a plurality of channels run one above the other or side by side in the throughput member. Since it is desirable to make the channels as large as possible while keeping the overall height as low as possible, the sealing surfaces between the individual channels are reduced to a minimum, and this then causes lack of tight sealing particularly readily.
The valve should also be easy to operate; the throughput member must therefore be easy to turn. In general there is not sufficient in a filter press for long levers with a horizontal direction of rotation. The space is limited by the permissable spacing between plates.
For reasons of supervision the working position in which the valve is at any time should be easily discernable from outside. In the previously proposed valves this is possible only under certain conditions, because generally only a round or predominantly oval hand wheel can be used.
For reasons of cost, filtration valves may be composed of synthetic materials, for instance polypropylene, with good resistance to the active chemicals used in the filtration. These materials have, in general, the disadvantage of high thermal expansion, due to the nature of the material. Throughput member valves consisting of this material, therefore, either fail to produce tight sealing during the changes of temperature that occur during a filtration process, or else the thermal expansion at least disadvantageously affects the mobility, that is to say the operability of the throughput members. On the other hand, lack of tight sealing gives rise to problems in operation (spraying of chemicals) and leads to losses of material.
SUMMARY OF THE INVENTION
According to the present invention, there is provided in a valve, means defining a multi-part casing, said casing comprising a first casing part, a second casing part, and at least two fluid flow connections, a membrane located in the casing in between the first and second casing parts and acting as a dividing wall between these parts, a switching member mounted in the casing, said switching member having at least one switching surface bearing against the membrane, said switching member being movable into a plurality of switching positions to provide for selected communication between, or closure of, the connections and means for moving the switching member between the switching positions.
In a preferred embodiment of the invention, improved functional efficiency, safety in operation and ease of operation can be effected by an arrangement in which a resilient rubber membrane is clamped between the casing parts and the switching member is formed as a friction member with at least one switching surface which bears against the membrane and closes or releases one or more connections in each of various switching positions. At the same time the membrane separates the part of the casing in contact with the chemicals from the part of the casing containing the mechanical components of the valve, which later casing part is thereby hermetically sealed. This permanently ensures operability, because for instance crystallization and fouling will not impair the functioning of the movement mechanism. In addition, the membrane is the only part of the valve that is subjected to wear. The membrane can be removed and replaced on the filter press itself, so that long interruptions of operation are eliminated. Advantageously the switching member is pivotally movable by means of a switching lever, of bifurcated form. The switching member has two pressure contact surfaces with a projection between these two surfaces to prevent the membrane from bulging when the switching member is in certain positions. The member may alternatively be provided with contact pressure rollers or operate in conjunction with drag levers.
The switching member may alternatively be formed as a slide member without any curved surfaces.
With the preferred construction, tight sealing of the valve is always ensured even in the case of high temperature differences during the filtration cycle and even in the case of crystallization, fouling and the like. The valve may have a comparatively small flange width, but with connections having a comparatively large cross-section so that in a given unit of time substantially larger quantities of liquid can be carried than in the case of the previously proposed valves having a throughput member. Whereas in these previously proposed valves, an enlargement of the connection cross sections automatically necessitates a larger throughput member diameter, this dependency is not present in the above preferred construction. On the other hand, the small flange width of the valve permits the use of extremely thin filter plates, which again increases the capacity and leads to greater commercial efficiency.
On the side facing towards the switching surface of the switching member, a slide sheet is clamped at each end. In order to prevent lateral displacement, this sheet may also be guided by a special rib profile. The sheet may alternatively be endless, so that in this case it extends round the switching member. Instead of the sheet a closed ring of solid material may alternatively perform the same function. The slide sheet is preferably made from a material with a low coefficient of friction. By this means, displacement of the membrane during the actuation of the switching member is avoided. However, if the membrane is made from a material with a small co-efficient of friction, the intermediate sheet may, in certain cases, be dispensed with. It is also possible to provide the switching member with rollers on its switching surfaces, in order to transform the sliding movement into a rolling movement.
Two end stops are provided on one of the casing parts for the switching lever which effects movement of the switch member and these end stops define two of the switching positions thereof. In these switching positions and in a further switching position recesses are provided on the casing part, a resilient detent member carried by the switch lever engaging in these recesses. In this manner it is possible to avoid errors of operation. Also, the individual switching positions may be accurately marked by suitable inscriptions or symbols on the casing part. By means of the switching lever, the position in which the switching member is located at any time is indicated by a clearly recognisable different angular position of the lever. Accordingly, it is possible for the operators of a filter press easily to supervise the valve region of the press fittings, even from a distance, that is to say, at once to recognise wrong lever positions or different switching positions of individual plates in abnormal situations (for instance turbid running). This is particularly important in the case of the very long filter presses. To simplify assembly, the switching lever may consist of two halves which engage laterally from outside in the casing part and the switching member installed in this casing part. Preferably these halves are pressed one against the other, so as to coincide exactly, in guides (pins and bushes or tongue and groove) and are held firmly together by a hood-like cover. This cover itself is engaged by an undercut on the handle part of the lever and is thereby fixed. The cover may have a through bore in its upper part, for the purpose of pulling it out of engagement again by the application of a force, in order to facilitate assembly. Mechanisation of valve actuation is also possible by means of these bores. The handle cover can also be made in different colours, in order by this means to show the function of the valve or of the respective filter plate or the nature of the installed switching member. The connection between the two halves of the lever may alternatively be effected by screws, rivets or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described by way of example only with reference to the accompanying diagrammatic drawings, in which
FIG. 1 is a perspective view partly in section, of a valve in accordance with the invention;
FIG. 2 is a vertical section taken on line II--II of FIG. 1;
FIGS. 3 to 5 are elevations, partly in section, showing three different switching positions of the valve;
FIGS. 6 to 8 are elevations, partly in section, through a second embodiment of a valve in accordance with the invention and showing three different switching positions of the valve; and,
FIG. 9 is a section taken on lines IX--IX of FIGS. 5 and 6.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The valves to be described hereinafter can be used in many different applications, but for the sake of simplicity, they will be described with reference to a filter press. Further the valves particularly described have three connections, although it will be apparent that they may have more than three connections.
As shown in FIGS. 1 to 5, the valve has a casing comprising an upper casing part 1 and a lower casing part 2, which are interconnected by means of flanges and screws. The casing 1, 2 is of generally disc-like form. Three connections 4, 5 and 6 are provided in the lower casing part 1, the connections 4 and 5 communicating with a flange 9 by way of corresponding tubular pipe sections 7 and 8. The connection 6 communicates with a tubular pipe section 10, through which the filtrate can be discharged into the open. As can be seen for instance from FIGS. 3 to 5, a switch member 11 is mounted in the casing 1, 2 so as to be capable of being rotated by means of a bifurcated switching lever 12. The switch member 11 is formed as a friction member and has switching surfaces 11a and 11d; a curved surface 11c, 11b is adjacent to the switching surfaces 11a, 11d respectively.
A membrane 13 is clamped between the upper casing part 1 and the lower casing part 2 and co-operates with the member 11 in a manner to be described hereinafter. The side of the membrane 13 facing the switching surface 11a carries a sheet or layer 14 of a suitable material to provide protection against wear and to reduce friction. The membrane 13 preferably consists of a resilient and corrosion-resistant material, for instance rubber or plastics. On the upper casing part 1 two end stops 15 and 16 and two associated recesses 17 are provided; in two of its switching positions, the switching lever 12 bears against a respective one of these stops 15, 16. The two end stops 15 and 16 accordingly limit the range of pivotal movement of the switching lever 12. When the switching lever 12 engages either one of the stops 15, 16, a resilient detent member 18 carried by the switching lever 12 engages in the associated recess 17 to releasably lock the switching lever 12. The detent member 18 can consist of a resilient plastics member, a ball biassed by means of a spring, or a resiliently mounted roller. A third, intermediate, recess 17 is provided to enable the switching lever to be releasably locked in an intermediate position between the stops 15, 16. Engagement may take place on one or both sides of the upper casing part 1.
In the upper casing part 1, two lobe-shaped walls 1a and 1b (FIG. 9) are provided, which engage in the lower casing part 2 and serve as supporting surfaces for side walls 13a of the membrane 13. A part of the member 11 is mounted between walls 1a and 1b. The side walls 2a of the lower casing part 2 are parallel to the walls 1a and 1b of the upper casing part 1, as is clearly shown in FIG. 9. A gap A is defined between each side wall 2a and the adjacent wall 1a or 1b, the gap A being greater than the thickness d of the membrane 13. By this means, chambers K are formed at each side of the side walls 13a.
The operation of the valve shown in FIGS. 1 to 5 will now be described.
FIG. 3 shows a switching position in which the connection 6 is closed whereas communication between the two connections 4 and 5 is established. In this position, the switching surface 11a of the member 11 bears firmly against the membrane 13, so that the connection 6 is completely closed. The filtrate therefore cannot be led away to the outside through the connection 6 and the pipe 10; instead, the filtrate follows the path shown by the arrow to be fed into a lower channel of a filter plate (not shown). In this case the switching lever 12 is in one of its end positions and bears against the end stop 15 and is releasably locked in this position by the detent member 18 engaged in the associated recess 17.
In the position shown in FIG. 4, the switching surface 11a of the member 11 closes the connection 4 by means of the membrane 13, whereas the two connections 5 and 6 communicate with one another. In this manner filtrate can be taken from the lower channel, and discharged into the open through the connection 6 and the pipe 10. In this case, the switching lever 12 is in its other end position in which it bears against the stop 16 and is releasably locked by means of the detent member 18 engaged in the associated recess 17.
In the position shown in FIG. 5 all three connections 4, 5 and 6 are separated from one another. In this position, the switching lever 12 is an intermediate position between the two end stops 15, 16 and is releasably locked in this position by engagement of the detent member 18 in the intermediate recess 17.
In the embodiment shown in FIGS. 1 to 5, the connections 4 and 5 or 5 and 6 can be placed in communication with another but there is no possibility of establishing communication between the connections 4 and 6, which may be desirable in certain cases. This possibility is provided in the embodiment shown in FIGS. 6 to 8. This embodiment differs from that of FIGS. 1 to 5 only in that the upper casing part 1 has been released from the lower casing part 2, and is again connected with the lower casing part 2 after having been pivotally moved through 180° about the axis of symmetry. In addition, the member 11 has been replaced by a different member with a shaft set in a different angular position. In this way the upper casing part 1 and the member 11 assume the positions shown in FIGS. 6 to 8.
In the position shown in FIG. 6, the switching surface 11a of the member 11 bears against the membrane 13 and in this way closes the connection 5, so that the two connections 4 and 6 communicate with one another by way of the chambers K (FIG. 9). In this way the filtrate coming out of the pipe 7 can be supplied by way of the connection 6 to the pipe 10 and discharged. As shown the pipe 10 extends parallel to the screw connection flange, that is to say vertically; alternatively, however, to provide better visibility of the filtrate discharge, the pipe may be inclined to the vertical. In the FIG. 6 position, the switching lever 12 bears against the end stop 16.
In the position shown in FIG. 7, the switching surface 11d, which is adjacent to the surface 11b, and the membrane 13 together bear against the connection 6 and close this connection. The connections 4 and 5, on the other hand, are in communication with one another. This position corresponds to the position according to FIG. 3, although the switching lever 12 is not vertical but is approximately horizontal and bears against the end stop 15.
The switching position according to FIG. 8 corresponds to the position according to FIG. 5. In this case also, the detent member 18 of the switching lever is engaged in the intermediate recess 17 of the upper casing part 1. Thus, in this position all three connections 4, 5 and 6 are separated from one another.
The membrane also performs the function of a seal between the upper and lower casing parts. In order to avoid unallowable deformation of the membrane 13, the two casing parts abut against one another and thereby limit the deformation distance. At the same time the membrane 13 is thereby shielded on the outside. In order to improve the sealing effect, instead of the flat sealing surfaces it may alternatively be possible to provide profiled surfaces (lamellae, curved members and the like) which in certain cases engage in corresponding recesses of the flanges of the upper and/or lower casing parts.
The upper and lower casing parts are preferably screwed together from underneath, so that the exposed screw threads are protected from active chemicals dripping down. Preferably the switching surface 11c ends in a projection 19, which prevents the membrane 13 from bulging into the upper casing part 1 when the membrane 13 in the loaded state cannot bear against one of the curved surfaces 11b or 11c. | A valve comprises a casing having two casing parts with a resilient membrane clamped between the parts. A switching member mounted within the casing deforms the membrane in each of a plurality of different switching positions, to selectively open and close communication between a plurality of connections of the valve. | 5 |
REFERENCE TO PRIOR PROVISIONAL APPLICATION
[0001] This application claims the benefit of prior copending provisional application No. 60/442,391, filed Jan. 24, 2003.
BACKGROUND OF THE INVENTION
[0002] This invention relates to abrasive saw blades of the type having a narrow, substantially flat-sided annular body typically composed of metal, an open central portion for movement of the workpiece through the blade, and an outer peripheral surface coated with an abrasive. The typical abrasive is a coating of powdered diamond particles applied in a sintering process and covering not only the outer periphery but also a portion of each flat side of the blade along the periphery. A saw assembly using blades of this type is shown in my U.S. Pat. No. 6,632,126 B1 (“the '126 patent”) issued Oct. 14, 2003 and entitled BLADE RING SAW ASSEMBLY.
[0003] Saws of the type shown in the above-identified patent support the ring-shaped blade around its inner and outer peripheries and rotate the blade at high speed to cut a workpiece with the abrasive-coated outer periphery. Because the blade is narrow and the interior of the blade is open, the workpiece can be turned during the cutting operation and moved within the blade to permit the blade to cut along irregular, curving paths. A typical use of such a blade is for cutting very hard materials such as tile. The flat-sided ring has sufficient strength to be driven through the tiles at substantial cutting rates. Details of construction and operation of such a saw assembly are shown and described in the above-identified patent, and have been made public through the advertising and sale of such saw assemblies by Gemini Saw Company of Torrance, Calif., under the trademark “Revolution.”
[0004] An earlier, lighter duty saw shown in U.S. Pat. No. 4,576,139, entitled “Rigid Wire Saw Wheel Apparatus For Very Hard Materials,” (“the '139 patent”) uses a diamond-coated wire ring that is supported and driven in a generally similar manner. This saw is designed for sawing glass and ceramics, but is not well-suited for heavy duty cutting because of limited cutting speed. With the flat-sided ring blade of the '126 patent, much greater cutting pressure can be applied and curved cuts can be made, although not as sharply curved as with a wire blade.
SUMMARY OF THE INVENTION
[0005] This invention resides in an improved flat-sided blade for blade ring saws in which the inner periphery of the ring and at least a portion of each flat side along the inner periphery also are covered with an abrasive coating, which protects the inner peripheral portion of the blade ring body from wear through contact with workpieces and, at the same time, utilizes the inner portion of the body as a grinder during the cutting of curves. This provides a smoother cutting action, a better finish on the workpiece, and the capability to cut much tighter curves. In essence, the trailing portion grinds in the opposite lateral direction from the leading portion during turning, thereby creating additional clearance for turning. Also, it is possible with such a blade to cut backwards, using the inner periphery as the leading edge.
[0006] The preferred embodiment of the invention has a sintered diamond coating on the outer peripheral portion, as shown in the '126 patent, covering part of each flat side along the outer periphery, and an electroplated diamond abrasive coating covering the inner periphery and the remainder of the unsintered body of the blade. The sintered coating is believed to provide a thicker coating with greater abrading capacity to perform the primary cutting function of the blade, and electroplating typically provides a thinner abrasive coating which does not wear away as quickly and therefore effectively protects the metal body while providing the edge-finishing function. Other coatings and coating patterns may be used, however, and the particular coating and patterns that are shown and described are not to be regarded as limitations.
[0007] An important advantage of this invention is substantially increased life of the saw blade. This is attributed to the protection of the body from damage, and the contribution of the trailing inner portion to the cutting capability after the leading outer cutting portion wears down.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a side elevational view of a blade ring saw blade embodying the novel features of the present invention;
[0009] FIG. 2 is an enlarged fragmentary elevational view of a portion of the outer peripheral edge of the blade shown in FIG. 1 ; and
[0010] FIG. 3 is a greatly enlarged fragmentary cross-sectional view taken along 3 - 3 of FIG. 1 , not exactly to scale, with diamond particles indicated diagrammatically on the inner peripheral portion, of the blade.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] As shown in the drawings for purposes of illustration, the presently preferred embodiment of a saw blade 10 for a blade ring saw assembly is an improvement on the basic saw blade shown in the '126 patent and sold by Gemini Saw Company as part of the “Revolution” saw, Reference is made to that patent for details of a representative saw assembly for use with a blade in accordance with the present invention. It will be evident that a blade of this type also may be used in a saw assembly of the general type shown in the '139 patent, with modifications.
[0012] As shown in the drawings, the blade 10 has a ring-shaped or annular body or core 11 ( FIG. 3 ) of suitable tool metal, preferably a carbon steel alloy. The blade has substantially flat sides 12 between circular outer and inner peripheral edges 13 and 14 , respectively, the inner peripheral edge defining a large open central portion of the blade.
[0013] The outer peripheral edge of the blade 10 is formed by an abrasive coating 15 on the body 11 , preferably a sintered powered diamond coating that extends partially over each side of the body. A short radial width of the outer portion 16 of the body preferably is of reduced thickness within the sintered coating, as shown in FIG. 3 , to receive a substantially greater thickness of wearable coating 15 . The portion 16 of the body that is reduced thickness is a rib that is thin enough to be worn away with the diamond coating in service use without interfering with the normal cutting action of the blade.
[0014] In accordance with the present invention, at least the side walls of the body 11 , and preferably the entire inner periphery of the body 11 , are covered with an abrasive coating 17 that protects the body against excessive wear and smooths the contact of the blade 10 with workpiece, both for a finer finish on the workpiece and for smoother operation and better wear of the saw blade. While this coating may take various forms, including a full sintered coating for the blade (not shown), the preferred coating is an electroplated diamond coating, shown as covering the remainder of the body of the blade that is not covered by the sintered coating 15 on the outer peripheral portion 16 . For functional purposes, the most important portion of the additional coating 17 is along both sidewalls close to the inner periphery, and secondarily on the inner edge 14 itself. It is convenient and preferred, however, simply to electroplate all of the body 11 that is not covered by the sintered layer, as shown.
[0015] As shown in FIGS. 2 and 3 , the inner peripheral edge 14 of the blade 10 may be rounded, as indicated, to modify and soften the grinding and finishing action of the inner portion during turning of a workpiece relative to the blade. The presently preferred configuration of the body 11 of the blade 10 , from the thicker outer diamond layer 15 to the inner edge, begins with substantially flat side surfaces 20 extending about halfway from the outer diamond layer 15 to the inner edge 21 of the body, and then tapering gradually at 22 toward the inner edge, at a small angle with the flat sides 20 , such as between ten and twenty degrees. The inner edge 21 is rounded so that the inner edge 14 formed by the diamond coating on this edge will be similarly rounded.
[0016] Blades for this type of saw assembly can be made in various sizes according to the parameters set forth in the '126 patent. As an example of a representative blade, not to be considered specific limitations, the blade 10 can have an outside diameter of approximately ten inches, an inside diameter of approximately nine and one-quarter inches, a metal body 11 or core approximately 0.042 to 0.052 of an inch thick, reduced to approximately 0.01 inches thick in the portion 16 inside the sintered diamond layer 15 . This layer may have a total thickness of approximately 0.55-0.65 of an inch and forms about one-half the radial width of the blade 10 . The electroplated coating 17 covers the remainder of the body 11 , to a thickness that preferably is not greater than the thickness of the sintered portion 15 on each side of the body, and may be slightly thinner so as to follow closely within the space, or “kerf” (not shown), cut in a workpiece during a straight cut, to avoid unnecessary enlargement of the kerf. The rounded inner edge 21 may be sized and shaped to produce an inner radius for the electroplated diamond coating on the order of 0.330 to 0.340 of an inch, the entire coating being approximately 0.010 to 0.015 of an inch thick.
[0017] Upon turning of the workpiece relative to the blade 10 to make a curved cut, the trailing inner edge 14 and the inner peripheral portion will swing out, relative to the direction of curvature, as the opposite side of the leading edge portion swings in, thereby moving into engagement with the curved side edge of the workpiece that has been formed by the cutting action of the leading edge of the blade. Because of the slight taper of the inner edge portion 22 of the body 11 and the corresponding taper of the inner diamond layer 17 , this swinging action on both sides of the inner edge will, in effect, slightly delay the contact of the inner diamond coating, at the inner edge, with the edge surface of the saw kerf, and thus will avoid harsh or excessive cutting engagement at the inner edge. This occurs in both directions of curvature, and produces a smoother cutting action of the blade 10 as well as a fine finishing or smoothing operation on the sidewalls of the workpiece.
[0018] Further, providing an abrasive coating on the inner peripheral edge 14 of the blade 10 provides the blade with the ability to cut reversely as well, during which the outer coating serves the smoothing and finishing function performed by the inner coating 17 during forward operation. This is a bonus value of the blade, which is designed for one-direction cutting movement as its primary function but sometimes can be operated to advantage in reverse.
[0019] It bears emphasis that the invention is an improvement in a flat-sided ring blade of the type disclosed in the '126 patent, in which the outer peripheral portion of the blade is coated with an abrasive coating to form an outer cutting element and the inner edge surface of the ring was bare metal. This had a tendency to cause blade wobble upon contact with a workpiece in the later stages of the life of a blade. Covering the exposed inner portion of the blade with abrasive cutting material not only provides a finishing action but also reduces blade wobble and maintains stability, and produces a substantial increase in the usable life of the blade.
[0020] Also to be noted is the fact that different abrasive coatings may be used on different portions of the blade 10 , with similar but somewhat varying results. Sintered diamond particles buried in powdered metal provide more effective cutting action than electroplated diamond particles, which typically provide a thinner layer. While an electroplated diamond coating could be used on the entire body, the preferred combination shown herein is believed to provide for optimum results—greater cutting capacity for the outer, primary cutting element and a durable abrasive coating for the inner, secondary cutting element.
[0021] A variety of different dimensions can be provided for a saw blade of this type, and a variety of abrasive coatings may be provided, all within the knowledge of those who are skilled in this art. This description is of a representative embodiment of the invention. Other modifications within the spirit and scope of the invention will be apparent to those skilled in the art. | A flat-sided annular blade for a blade ring saw for cutting hard materials such as tile along straight paths and curved paths in which the workpiece is moved through the central portion of the blade. In addition to the usual sintered abrasive diamond coating on the outer peripheral portion of the blade, the inner peripheral portion preferably is tapered to a curved inner edge and also is coated with an abrasive, preferably an electroplated diamond coating providing smoother sawing operation and a finishing action on the workpiece. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to push-button box-opening structures, and more particularly, to a push-button box-opening structure in which a push button is pushed in to open a box in a closed position.
BACKGROUND OF THE INVENTION
[0002] A storage box for holding small things is provided in the interior of an automobile. Some storage boxes are so constructed that a lid of a storage box is opened by depressing a depressed portion (hereinafter referred to as a “push button”) (e.g., Japanese Patent Laid-Open Publication No. 2002-331876).
[0003] A storage box disclosed in 2002-331876 includes a storage pocket for holding small things and a lid for opening and closing an opening of the storage pocket. The lid is provided with a locking hook and an unlocking push button.
[0004] To open the lid from a closed position, the push button is depressed to release engagement between the hook and a striker. Thus, since only depressing the push button permits the lid to open, a passenger can easily open the lid.
[0005] However, since the above storage box has the lid opened only by depressing the push button, when an object in the vehicle interior (hereinafter referred to as an impacting object) strikes the push button, the push button can be depressed by the impacting object. If the push button is depressed, the lid can be opened inadvertently. Thus, there is room for improvement in being able to prevent opening of the box even when the push button is inadvertently depressed.
SUMMARY OF THE INVENTION
[0006] According to the present invention, there is provided a push-button box-opening structure, which comprises: a box; a push button for opening the box; and a button housing for housing the push button in such a manner as to allow the push button to be pushed in from an unlocking starting position to an unlocking position to thereby open the box. The unlocking starting position is set at a position where the push button is pushed in a given depth from a pushing-in starting position.
[0007] The push button is provided in the button housing in such a manner that it can be pushed in. Until the push button is pushed into the button housing by the given distance or depth, the box remains closed. Thus, even when the push button is inadvertently pushed in, the box is prevented from opening until the push button is pushed in by the given depth.
[0008] When the push button is pushed into the button housing by the specified distance, further pushing of the push button into the unlocking position causes the box to open. Thus, a passenger can open the box only by pushing the push button in, and can easily open the box.
[0009] Preferably, a surface of the push button is located at substantially the same level as a rim of the button housing.
[0010] If the surface of the push button is protruded outwardly from the rim of the button housing, it is necessary to provide a large pushing-in distance of the push button against striking of an impacting object on the push button in order to keep the box closed. An increased pushing-in distance against striking of an impacting object results in an increased stroke of the push button for opening the box. The increased stroke of the push button requires a large space in which to dispose the push button to ensure the stroke.
[0011] On the other hand, if the surface of the push button is recessed inwardly of the rim of the button housing, the push button is not easily seen from a passenger and is not easily pushed in with a finger. In addition, it is not preferable in appearance.
[0012] For these reasons, in the present invention, the surface of the push button is located at substantially the same level as the rim of the button housing. Consequently, a stroke of the push button can be made relatively small to dispose the push button in a relatively small space.
[0013] Further, the surface of the push button located at substantially the same level as the rim of the button housing allows the push button to be easily seen from a passenger and to be easily pushed in with a finger, and also provides a good appearance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] A preferred embodiment of the present invention will be described in detail below, by way of example only, with reference to the accompanying drawings, in which:
[0015] FIG. 1 is a perspective view of an instrument panel provided with a push-button box-opening structure according to a first embodiment of the present invention;
[0016] FIG. 2 is a cross-sectional view along line 2 - 2 in FIG. 1 ;
[0017] FIG. 3 is a cross-sectional view along line 3 - 3 , in FIG. 1 ;
[0018] FIG. 4 is a perspective view showing the relationship between a push button and a locking means according to the first embodiment;
[0019] FIG. 5 is a cross-sectional plan view of FIG. 4 ;
[0020] FIGS. 6A and 6B are diagrams showing the push button in the first embodiment pushed in by a specified distance;
[0021] FIGS. 7A and 7B are diagrams showing the push button pushed in further from the position shown in FIG. 6B ;
[0022] FIGS. 8A and 8B are diagrams showing an instance where an impacting object strikes the push button in the first embodiment;
[0023] FIG. 9 is a cross-sectional view showing a push-button box-opening structure according to a second embodiment of the present invention;
[0024] FIGS. 10A and 10B are diagrams showing an instance where a push button in the second embodiment shown in FIG. 9 is pushed in to open a pocket; and
[0025] FIG. 11 is a diagram showing an instance where an impacting object strikes the push button in the second embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] First, with reference to FIGS. 1 to 8 B, a push-button box structure according to a first embodiment will be described.
[0027] An instrument panel 10 shown in FIG. 1 has a right end portion 11 provided with a box 12 in which to store small things.
[0028] The storage box 12 includes a pocket 13 provided in the light end portion 11 of the instrument panel 10 and a lid 15 for opening and closing an opening 14 of the pocket 13 . The lid 15 is supported by right and left hinge means 17 (only the left hinge means 17 shown in FIG. 2 ) to be swingable to a closed position P 1 (see FIG. 3 ) and to an open position P 2 (see FIG. 3 ). The storage box 12 has a push-button box-opening structure 20 in which a push button 21 is pushed in to open the lid 15 retained in the closed position P 1 .
[0029] The right and left hinge means 17 , 17 are constituted by identical components. Hereinafter, only the left hinge means 17 will be described to avoid a redundant description of the right hinge means 17 .
[0030] As shown in FIG. 2 , the lid 15 includes an outer wall 25 formed in a dogleg shape by a lower outer panel 23 and an upper outer panel 24 , and an inner panel 26 in a dogleg shape located inside the outer wall 25 . A space 27 of a predetermined clearance is formed between the outer wall 25 and the inner panel 26 .
[0031] A lower bracket 31 of the left hinge means 17 is attached to a left end lower portion of the inner panel 26 by a bolt 32 . An upper bracket 33 of the left hinge means 17 is attached to a left end of the instrument panel 10 by a bolt 34 . The upper bracket 33 and the lower bracket 31 are connected by a pair of links 35 , 35 . Thus, the left end of the instrument panel 10 is connected to the left end lower portion of the inner panel 26 via the left hinge means 17 .
[0032] Like the left hinge means 17 , the right hinge means 17 is used to connect a right end of the instrument panel 10 to a right end lower portion of the inner panel 26 via the right hinge means 17 .
[0033] The right and left hinge means 17 , 17 are used as described above, so that the lid 15 is mounted to the instrument panel 10 to be swingable to the closed position P 1 and to the open position P 2 (see FIG. 3 ).
[0034] The push button 21 of the push-button box-opening structure 20 is provided in a left end portion of the upper outer panel 24 (that is, in a left end upper portion of the lid 15 ) in such a manner that it can be pushed in. Specifically, the upper outer panel 24 has a button housing 36 including an opening formed in the left end portion thereof. The button housing 36 has guide grooves 37 a and 38 a formed in upper and lower walls 37 and 38 , respectively.
[0035] The push button 21 has upper and lower sliders 41 a and 42 a formed in such a manner as to protrude from upper and lower walls 41 and 42 thereof, respectively.
[0036] The upper slider 41 a is movably fitted in the upper guide groove 37 a , and the lower slider 42 a is movably fitted in the lower guide groove 38 a , so that the push button 21 is mounted movably as shown by a two-headed arrow in the button housing 36 .
[0037] A small-diameter cylindrical protrusion (hereinafter referred to as an “inner cylinder”) 43 is formed within the push button 21 . A large-diameter cylindrical protrusion (hereinafter referred to as an “outer cylinder”) 44 is sidably fitted onto the inner cylinder 43 .
[0038] The outer cylinder 44 has a flange 45 at the base. The flange 45 is fixed to a left end upper portion of the inner panel 26 .
[0039] A compression spring 46 is disposed between the flange 45 and a ceiling face 21 a of the push button 21 . The compression spring 46 biases the push button 21 in a direction in which to protrude it outwardly of the upper outer panel 24 .
[0040] The push button 21 , the outer cylinder 44 and the compression spring 46 are provided in the space 27 between the upper outer panel 24 and the inner panel 26 within the lid 15 .
[0041] Outer edge portions of the upper and lower sliders 41 a and 42 a abut outer edge portions 37 b and 38 b of the upper and lower guide grooves 37 a and 38 a , so that the push button 21 rests.
[0042] The outer edge portions 37 b and 38 b of the upper and lower guide grooves 37 a and 38 a and the outer edge portions of the upper and lower sliders 41 a and 42 a are positioned so that a surface 21 b of the push button 21 in the above state is flush with a rim 36 a of the button housing 36 and an outer surface 24 a of the upper outer panel 24 .
[0043] A position in which the surface 21 b of the push button 21 is substantially flush with the rim 36 a of the button housing 36 and the outer surface 24 a of the upper outer panel 24 (that is, a position shown in FIG. 2 ) is a pushing-in starting position P 3 . Pressure applied to the surface 21 b inwardly of the lid 15 causes the push button 21 to be pushed against the spring force of the compression spring 46 into the button housing 36 .
[0044] As shown in FIG. 3 , a locking means 50 of the push-button box-opening structure 20 is provided in an upper substantially central portion of the lid 15 .
[0045] The locking means 50 includes a latch 51 formed with an engagement groove 53 . The latch 51 is rotatably provided with a pin 52 . Engagement of a striker 54 with the engagement groove 53 retains the lid 15 in the closed position P 1 to keep the storage box 12 (see FIG. 1 ) closed.
[0046] The locking means 50 has a coil spring 55 mounted on the pin 52 . A first end 55 a of the coil spring 55 is inserted into a mounting hole 51 a formed in the latch 51 , and a second end 55 b is inserted into a mounting hole 28 a formed in a bracket 28 , so that the latch 51 is biased in the direction of an arrow, that is, in an opening direction of the lid 15 . The bracket 28 is a member attached to the inside of the outer wall 25 .
[0047] The latch 51 has a positioning depression 57 formed in a lower portion thereof. The positioning depression 57 positions the latch 51 in a locking position (position shown in FIG. 3 ). A lock bar 58 placed against the positioning depression 57 retains the latch 51 in the locking position against the spring force of the coil spring 55 .
[0048] When the lock bar 58 is disengaged from the positioning depression 57 , the latch 51 rotates about the pin 52 in the direction shown by the arrow by the spring force of the coil spring 55 , and the lid 15 swingingly moves about the hinge means 17 shown in FIG. 2 , so that the engagement groove 53 of the latch 51 disengages from the striker 54 . Thereafter, the lid 15 swingingly moves by a spring not shown from the closed position P 1 to the open position P 2 (position shown by imaginary lines). With this, the storage box 12 (see FIG. 1 ) opens.
[0049] The striker 54 has a U shape as shown in FIG. 4 . Opposite end portions 54 a , 54 a of the striker 54 are inserted into mounting holes 61 , 61 in the instrument panel 10 , and nuts 62 , 62 are screw-connected to the end portions 54 a , 54 a protruded from the instrument panel 10 , respectively. Thus, the striker 54 is attached to the instrument panel 10 .
[0050] As shown in FIG. 4 , the push button 21 is provided in the button housing 36 in such a manner that it can be pushed in. Until the push button 21 is pushed into the button housing 36 by a specified distance, the locking means 50 is kept in a non-operated position. After the push button 21 is pushed into the button housing 36 by the specified distance, the push button 21 further pushed in releases the locking means 50 from the locking position. The shape of the button housing 36 (specifically, the height H of the button housing 36 ) is so determined that, when an impacting object 65 (see FIG. 8 ) strikes the push button 21 , the rim 36 a of the button housing 36 and the outer surface 24 a of the upper outer panel 24 sustain the impacting object 65 , preventing the push button 21 from being pushed into the button housing 36 by the specified distance.
[0051] In a comparison between the height H and the width W of the button housing 36 , the height H is smaller than the width W. Therefore, the intruding distance of the impacting object 65 into the button housing 36 is restricted by the height H.
[0052] A pushing protrusion 67 for pushing is provided at a side wall 47 of the push button 21 . An operating link 68 is rotatably provided about a pin 69 in front of (in a pushing direction of) the pushing protrusion 67 . The operating link 68 has a first lever 71 extending in a curve toward the pushing protrusion 67 , and a second lever 72 extending rearward.
[0053] A distal end portion 71 a of the first lever 71 is disposed at a certain distance from the pushing protrusion 67 . A distal end portion 72 a of the second lever 72 is inserted into an insertion hole 74 formed in a distal end portion 73 a of a slider 73 and connected to the distal end portion 73 a of the slider 73 via a connecting pin 75 .
[0054] A connection hole 76 is formed in a proximal end portion 73 b of the slider 73 . A bent portion 58 a formed at a first end portion of the lock bar 58 is inserted into the connection hole 76 , whereby the bent portion 58 a of the lock bar 58 is connected to the proximal end portion 73 b of the slider 73 .
[0055] A second end portion 58 b of the lock bar 58 is placed against the positioning depression 57 formed in the latch 51 . The latch 51 is retained in the locking position against the spring force of the coil spring 55 . With this, the engagement groove 53 in the latch 51 engages the striker 54 , and the lid 15 (see FIG. 3 ) is retained in the closed position P 1 .
[0056] When the surface 21 b of the push button 21 is pressed to push the push button 21 into the button housing 36 , the pushing protrusion 67 abuts on the distal end portion 71 a of the first lever 71 , and the distal end portion 71 a of the first lever 71 is pushed out forward by the pushing protrusion 67 .
[0057] The relationship between the pushing-in distance of the push button 21 and the timing of abutting of the pushing protrusion 67 against the distal end portion 71 a of the first lever 71 will be described in detail below with FIG. 5 .
[0058] When the distal end portion 71 a of the first lever 71 is pushed out forward by the pushing protrusion 67 , the operating link 68 rotates as shown by an arrow, and the second lever 72 causes the slider 73 to slide as shown by an arrow.
[0059] The slider 73 sliding as shown by the arrow causes the lock bar 58 to move as shown by an arrow, and the second end portion 58 b of the lock bar 58 disengages from the positioning depression 57 in the latch 51 .
[0060] The locking means 50 is released from the locking position, and the latch 51 rotates about the pin 52 as shown by an arrow by the spring force of the coil spring 55 . The engagement groove 53 of the latch 51 disengages from the striker 54 as described above.
[0061] The push button 21 , the outer cylinder 44 , the compression spring 46 , the operating link 68 , the slider 73 , the lock bar 58 , the locking means 50 and the striker 54 are provided in the space 27 between the upper outer panel 24 and the inner panel 26 shown in FIG. 3 , and are thus provided within the lid 15 .
[0062] As shown in FIG. 5 , the push button 21 is disposed in the pushing-in starting position P 3 so that the locking means 50 is in the locking position, that is, the second end portion 58 b of the lock bar 58 is engaged with the positioning depression 57 of the latch 51 (see also FIG. 4 ). In this state, the distal end portion 71 a of the first lever 71 is disposed at a specified distance D 1 from the pushing protrusion 67 of the push button 21 . With this, unless the push button 21 is pushed by the specified distance D 1 into the button housing 36 so that the push button 21 reaches an unlocking starting position P 4 , the pushing protrusion 67 does not abut on the distal end portion 71 a of the first lever 71 . Therefore, when the push button 21 is pushed into the button housing 36 as shown by an arrow by a pushing-in distance smaller than the specified distance D 1 , the operating link 68 is kept at rest, and the locking means 50 is kept in the locking position.
[0063] When the push button 21 is further pushed in from the position where the pushing protrusion 67 of the push button 21 abuts on the distal end portion 71 a of the first lever 71 , the pushing protrusion 67 of the push button 21 pushes out the distal end portion 71 a of the first lever 71 forward.
[0064] The pushing protrusion 67 pushing the distal end portion 71 a of the first lever 71 forward causes the operating link 68 to rotate about the pin 69 as shown by an arrow. The rotation of the operating link 68 causes the second lever 72 to slide the slider 73 as shown by an arrow, causing the lock bar 58 to move as shown by the arrow.
[0065] When the pushing-in distance of the push button 21 becomes equal to an operating distance D 2 and the push button 21 reaches an unlocking position P 5 , the second end portion 58 b of the lock bar 58 pulls out from the positioning depression 57 of the latch 51 . This releases the locking means 50 from the locking position, and the latch 51 rotates about the pin 52 by the spring force of the coil spring 55 as shown by an arrow. The engagement groove 53 of the latch 51 disengages from the striker 54 , and the lid 15 is opened by the spring not shown from the closed position P 1 (see FIG. 3 ) to the open position P 2 (see FIG. 3 ).
[0066] Thereafter, the push button 21 is further pushed in by a bottom-touching distance D 3 to cause the push button 21 to abut on the flange 45 and rest, and thereby to confirm that the push button 21 is certainly pushed into the unlocking position.
[0067] Next, with reference to FIGS. 6A to 7 B, an instance of opening the lid 15 with the push button 21 will be described.
[0068] Referring to FIG. 6A , the push button 21 in the pushing-in starting position P 3 is pushed into the button housing 36 as shown by arrow a against the spring force of the compression spring 46 .
[0069] Referring to FIG. 6B , the push button 21 is pushed in by the specified distance D 1 to the unlocking starting position P 4 to make the pushing protrusion 67 abut on the distal end portion 71 a of the first lever 71 . From this position, the push button 21 is pushed in by the operating distance D 2 (see FIG. 5 ) to the unlocking position P 5 to cause the pushing protrusion 67 of the push button 21 to push out the distal end portion 71 a of the first lever 71 forward.
[0070] With the distal end portion 71 a of the first lever 71 pushed out forward, the operating link 68 rotates about the pin 69 as shown by arrow b, causing the second lever 72 to slide the slider 73 as shown by arrow c. The slide of the slider 73 causes the lock bar 58 shown in FIG. 5 to move as shown by the arrow.
[0071] Referring to FIG. 7A , when the push button 21 reaches the unlocking position P 5 and the pushing-in distance of the push button 21 is (specified distance D 1 +operating distance D 2 ), the second end portion 58 b of the lock bar 58 disengages from the positioning depression 57 of the latch 51 .
[0072] Referring to FIG. 7B , the locking means 50 is released from the locking position, and the latch 51 rotates about the pin 52 as shown by arrow d by the spring force of the coil spring 55 . The engagement groove 53 of the latch 51 disengages from the striker 54 , and the lid 15 swingingly moves from the closed position P 1 (see FIG. 3 ) to the open position P 2 (see FIG. 3 ) by the spring not shown as shown by arrow e. Thus, the lid 15 swingingly moves to the open position P 2 , thereby opening the storage box 12 (see FIG. 1 ).
[0073] The latch 51 rotating about the pin 52 as shown by the arrow d is retained in a predetermined position by the positioning depression 57 abutting on a stopper 28 b , so as not to rotate over the position.
[0074] Next, a situation where the impacting object 65 strikes the push button 21 will be described with reference to FIGS. 8A and 8B .
[0075] Referring to FIG. 8A , when the impacting object 65 strikes the push button 21 as shown by arrow f, the impacting object 65 is sustained by the rim 36 a of the button housing 36 and the outer surface 24 a of the upper outer panel 24 .
[0076] As described with FIG. 4 , the button housing 36 is formed with the width W and the height H, the height H being smaller than the width W. The intruding distance of the impacting object 65 into the button housing 36 is restricted by the height H, and the intruding distance of the push button 21 is limited to D 4 .
[0077] Referring to FIG. 8B , with the intruding distance of the impacting object 65 into the button housing 36 restricted to D 4 by the height H (see FIG. 8A ), the intruding distance D 4 of the impacting object 65 can be made smaller than the specified distance D 1 . Therefore, the push button 21 does not reach the unlocking starting position P 4 .
[0078] As shown in FIG. 5 , with the push button 21 disposed in the pushing-in starting position P 3 , the distal end portion 71 a of the first lever 71 is disposed at the specified distance D 1 from the pushing protrusion 67 of the push button 21 . Therefore, when the impacting object 65 strikes the push button 21 , the pushing protrusion 67 does not abut on the distal end portion 71 a of the first lever 71 .
[0079] The operating link 68 is retained at rest, and the locking means 50 (see FIG. 5 ) is kept in the locking position. This allows the lid 15 to rest in the closed position P 1 (see FIG. 3 ) to keep the storage box 12 (see FIG. 1 ) closed.
[0080] Next, a box opening structure according to a second embodiment of the present invention will be described with reference to FIGS. 9 to 11 .
[0081] FIG. 9 shows an instrument panel according to the second embodiment.
[0082] An instrument panel 80 has a right end portion 81 provided with a storage box (box) 82 according to the present invention.
[0083] The storage box 82 includes a pocket 83 provided in the right end portion 81 of the instrument panel 80 , a lid 85 provided at an outer wall 84 of the pocket 83 , and a push button 91 of a push-button box-opening structure 90 provided above the pocket 83 .
[0084] The push-button box-opening structure 90 has substantially the same structure as the push-button box-opening structure 20 in the first embodiment.
[0085] The pocket 83 is configured to swingingly move about a lower pin (not shown) as shown by arrow h so that an opening 86 of the pocket 83 protrudes outwardly from the instrument panel 80 , and to swingingly move about the lower pin (not shown) as shown by arrow i so that the opening 86 is fitted in the instrument panel 80 .
[0086] Abase 92 of the push button 91 is connected to the instrument panel 80 via a tension spring 93 . Abutton body 94 of the push button 91 is opposed to a button housing (recess) 96 . The push button 91 is retained in a pushing-in starting position P 3 by the spring force of the tension spring 93 .
[0087] When the push button 91 is located in the pushing-in starting position P 3 , a surface 91 a of the push button 91 is substantially flush with a rim 96 a of the button housing 96 and an outer surface 96 b around the rim 96 a.
[0088] To open the pocket 83 , pressure is applied to the button body 94 of the push button 91 as shown by arrow g to push the button body 94 into the button housing 96 against the spring force of the tension spring 93 by a predetermined distance (that is, specified distance D 1 +operating distance D 2 ) to an unlocking position P 5 .
[0089] This releases the lock of a locking means (not shown), and causes the pocket 83 to swingingly move about the lower pin (not shown) as shown by the arrow h. Then, the opening 86 of the pocket 83 protrudes outwardly from the instrument panel 80 to open the pocket 83 (that is, the storage box 82 ).
[0090] The locking means has substantially the same structure as the locking means 50 in the first embodiment (see FIGS. 4 and 5 ).
[0091] To close the pocket 83 , pressure is applied to the lid 85 to push the pocket 83 in about the lower pin (not shown) as shown by the arrow i. The opening 86 of the pocket 83 is fitted in the instrument panel 80 to close the pocket 83 .
[0092] Like the push button 21 in the first embodiment, even when the button body 94 of the push button 91 in the second embodiment is pushed into the button housing 96 by the specified distance D 1 from the pushing-in starting position P 3 to an unlocking starting position P 4 , the locking means of the push-button box-opening structure 90 is kept in a locking position.
[0093] By further pushing the button body 94 in from the unlocking starting position P 4 to which the button body 94 has been pushed in by the specified distance D 1 , the locking means of the push-button box-opening structure 90 is operated.
[0094] When the pushing-in distance of the button body 94 becomes equal to the operating distance D 2 and the button body 94 reaches the unlocking position P 5 , the locking means is released from the locking position.
[0095] The release from the locking position causes the pocket 83 to swingingly move about the lower pin (not shown) as shown by the arrow h to open the pocket 83 , that is, the storage box 82 ,
[0096] Thereafter, by further pushing the button body 94 in by a bottom-touching distance D 3 , the button body 94 abuts on a stopper (not shown) and rests, and a passenger confirms that the button body 94 is certainly pushed into the unlocking position.
[0097] Next, an instance of opening the pocket 83 with the push button 91 of the push-button box-opening structure 90 according to the second embodiment will be described with reference to FIGS. 10A and 10B .
[0098] Referring to FIG. 10A , the push button 91 is retained in the pushing-in starting position P 3 by the tension spring 93 and the locking means. The button body 94 of the push button 91 is pushed against the spring force of the tension spring 93 into the button housing 96 as shown by arrow g.
[0099] Referring to FIG. 10B , the button body 94 is pushed in by the specified distance D 1 to the unlocking starting position P 4 (see FIG. 9 ). From this position, the button body 94 is further pushed in to operate the locking means of the push-button box-opening structure 90 .
[0100] When the button body 94 is pushed in by the specified distance D 1 +the operating distance D 2 to the unlocking position P 5 , the locking means is released from the locking position, and the pocket 83 swingingly moves about the lower pin (not shown) as shown by arrow h to open the pocket 83 , that is, the storage box 82 .
[0101] Next the operation of the push-button box-opening structure 90 in the second embodiment when an impacting object 65 strikes the push button 91 will be described with reference to FIG. 11 .
[0102] When the impacting object 65 strikes the button body 94 of the push button 91 as shown by arrow j, the impacting object 65 is sustained by the rim 96 a of the button housing 96 and the outer surface 96 b around the rim 96 a . Thus, the intruding distance of the impacting object 65 into the button housing 96 is restricted by the rim 96 a of the button housing 96 and the outer surface 96 b around the rim 96 a , and the intruding distance of the button body 94 is limited to D 4 . The intruding distance D 4 is smaller than the specified distance D 1 .
[0103] The intruding distance D 4 of the button body 94 made smaller than the specified distance D 1 allows the locking means to be kept in the locking position even when the impacting object 65 strikes the button body 94 . This allows the pocket 83 to rest in a closed position to keep the storage box 82 closed.
[0104] In the first embodiment, the storage box (glovebox) 12 provided in the instrument panel 10 is illustrated as a box to which the present invention is applied. The present invention is also applied to an ashtray, a cup holder and the like.
[0105] The first embodiment has been described with the example in which the specified distance D 1 for preventing the storage box 12 from opening is provided by disposing the distal end portion 71 a of the first lever 71 at a certain distance from the pushing protrusion 67 . However, the structure for providing the specified distance D 1 is not limited thereto. Another means such as elongating the connection hole 76 for connecting the lock bar 58 to the slider 73 can also provide the specified distance D 1 .
[0106] As described above, a push-button box-opening structure of the present invention is so constructed that a box in a closed position is opened by pushing a push button in, and is suitable for application to automobiles.
[0107] Obviously, various minor changes and modifications of the present invention are possible in the light of the above teaching. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described. | A push-button box-opening structure is provided in which a push button is pushed in from an unlocking starting position to an unlocking position to open a storage box. The unlocking starting position is set at a position where the push button is pushed in a given depth from a pushing-in starting position so as to prevent inadvertent opening of the storage box. The storage box does not open when the button is inadvertently pushed in up to the given depth. | 8 |
This application claims the benefit of U.S. provisional application No. 60/116,121, filed Jan. 15, 1999.
FIELD OF THE INVENTION
This invention pertains to the field of ventilatory support for respiratory failure, particularly due to lung disease, and in particular to automatically providing sufficient end expiratory pressure to unload intrinsic positive end expiratory pressure (PEEPi)
BACKGROUND OF THE INVENTION
Subjects with chronic airflow limitation (CAL) due, for example, to emphysema and chronic bronchitis, may require ventilatory assistance, particularly during periods of acute exacerbation, or routinely at night.
Ventilatory support can reduce the work of breathing, reduce the sensation of breathlessness, and improve blood gases (oxygen and carbon dioxide levels). In subjects with CAL, most of the work of breathing is due to the high airway resistance. Approximately two thirds of this resistance is relatively fixed, and due to narrowing of the airways. However, of the order of one third of the resistance is due to dynamic airway compression during expiration. Dynamic airway compression occurs when the pleural pressure exceeds the pressure in the lumen of the airway during expiration, causing flow to become independent of effort.
In a normal subject, the alveolar pressure decays exponentially during expiration, so that the expiratory flow and alveolar pressure (relative to atmospheric) are both approximately zero at the end of expiration, and the lungs and chest wall have returned to their passive equilibrium volume V R . In patients with CAL, however, as a result of dynamic airway compression and fixed reduced expiratory flow rate, it is not possible for the lungs to return to V R in the time allowed before the start of the next inspiration. The chest is hyperinflated. The alveolar pressure remains positive, on the order of 5 to 15 cmH 2 O at the end of expiration. This raised alveolar pressure is termed intrinsic positive end expiratory pressure, or PEEPi. (Other names for the phenomenon are covert PEEP and occult PEEP.)
An important effect of the hyperinflation is that the patient must overcome the elastic recoil of the hyperinflated chest wall before inspiratory airflow can commence. The PEEPi is said to act as an inspiratory threshold load. A further undesirable effect of PEEPi is that during artificial mechanical ventilatory support, it interferes substantially with the triggering of the ventilator, causing patient-machine asynchrony.
It is now well understood that the addition of a counterbalancing external positive end expiratory pressure (called external PEEP, or just PEEP), approximately equal in magnitude to PEEPi, is of great benefit. First, it prevents dynamic airway compression, permitting greater expiratory airflow. Second, it balances the inspiratory threshold load. Third, it improves triggering of a ventilator by the patient.
Use of excessive PEEP, however, can be disadvantageous and even dangerous. Excessive PEEP above and beyond PEEPi will cause yet further hyperinflation. This will result in stiffening of the lung and chest wall, and an increase in the elastic work of breathing. It will also cause reduced cardiac output, and can lead to barotrauma. Further, the peak inspiratory airway pressure during ventilatory support cannot be arbitrarily increased without either exceeding the capacity of the ventilator, or reaching a pressure that is itself dangerous. Finally, excessive external PEEP will also reduce the possible airway pressure excursion or headroom available for lung inflation.
Therefore, it is advisable when applying external PEEP to set the external PEEP as close as possible to PEEPi. Since PEEPi varies from time to time, depending on a number of factors including, for example, the resistance of the small airways and the respiratory rate, both of which change with changing sleep stage, chest infection, or bronchospasm, it is desirable to be able to make multiple, or even continuous, measurements of PEEPi in order to optimize external PEEP.
A typical patient in an intensive care unit is heavily sedated and paralyzed during ventilatory support, and it is straightforward to measure the PEEPi. It is necessary only to occlude the airway during late expiration, and measure the airway pressure, which, after a few seconds of equilibration, will equal static PEEPi. Since the lung injury in CAL is usually markedly heterogeneous, different alveoli will have different end expiratory pressures, and static PEEPi is therefore a weighted average across all alveoli.
Another known method which is suitable for use in the paralyzed sedated patient is to measure the airway pressure at the start of machine inspiratory effort, and again at the start of actual inspiratory airflow. The difference between these two pressures is the dynamic PEEPi. Dynamic PEEPi reflects the end expiratory pressure in the least abnormal lung units, and substantially underestimates static PEEPi.
These simple methods do not work for patients who are not sedated and paralyzed, and who are making spontaneous breathing efforts, because they do not take into account the patients' own respiratory muscle efforts.
One known method that is used with such patients requires a Muller manoeuvre (maximal inspiratory effort) during catheterization of the oesophagus and stomach, and is therefore completely unsatisfactory for repeated or continuous measurements in the ambulatory patient or the patient who is being treated at home long-term.
Methods for measuring the airway conductance in spontaneously breathing patients using oscillometry are taught by Peslin et al., Respiratory Mechanics Studied by Forced Oscillations During Mechanical Ventilation , Eur Respir J 1993; 6:772-784, and by Farre et al., Servo Controlled Generator to Measure Respiratory Impedance from 0.25 to 26 Hz in Ventilated Patients at Different PEEP Levels , Eur Respir J 1995; 8:1222-1227. These references contemplate separate measurements for inspiration and expiration. Oscillometry requires modulation of the airway pressure at a high frequency, such as 4 Hz, and measurement of the resultant modulation of the respiratory airflow at that frequency. However, these references fail to describe servo-controlling of ventilation to increase or decrease PEEP so that the inspiratory arid expiratory conductances are approximately equal.
Oscillometry has been used to control nasal CPAP (see U.S. Pat. No. 5,617,846) or bilevel CPAP for the treatment of obstructive sleep apnea (see U.S. Pat. No. 5,458,137). The problem there is essentially opposite to the problem under consideration here. In obstructive sleep apnea, there is increased resistance during inspiration, and the above two patents teach that increased resistance during inspiration can be treated by an increase in pressure. In patients with CAL and dynamic airway compression, there is increased resistance during expiration.
There is no known method or apparatus which can automatically or continuously control a ventilator or CPAP apparatus in conscious spontaneously breathing patients in order to prevent expiratory airflow limitation or to unload PEEPi in CAL.
Yet another known method for estimating PEEPi, taught, for example, by Rossi et al., The Role of PEEP in Patients with Chronic Obstructive Pulmonary Disease during Assisted Ventilation , Eur Respir J 1990; 3:818-822, is to examine the shape of the expiratory flow-volume curve, which has been observed to be exponential, if there is no dynamic airway compression. The reference further notes that in the absence of PEEPi, the flow-volume curve becomes a straight line.
The above known art only contemplates the application of an external pressure which is constant during any one expiratory cycle. However, the elastic recoil of the lung is higher at high lung volume, and lower at low lung volume. Therefore, it may be advantageous to find the minimum external pressure at each moment in time during an expiration that will prevent dynamic airway compression during that expiration.
It is an object of our invention to vary the ventilatory pressure during expiration as a function of the degree of the patient's dynamic airway compression.
It is another object of our invention to vary the ventilatory pressure automatically based solely on continuous measurements that are already taken in conventional CPAP and ventilator apparatuses.
SUMMARY OF THE INVENTION
The present invention seeks to provide continuous and automatic adjustment of the expiratory pressure during ventilatory support, so as to substantially prevent dynamic airway compression and unload intrinsic PEEP with the smallest amount of external expiratory pressure.
The basic method of the invention prevents dynamic airway compression during ventilatory support using a conventional interface to a patient's airway such as a face mask, nose mask, or endotracheal or tracheotomy tube, and providing the interface with an exhaust and a supply of breathable gas at a variable pressure as is known in the CPAP and ventilatory arts. The respiratory airflow is determined by measurement or calculation, and a measure of the degree of dynamic airway compression is derived. This measure is servo-controlled, preferably to be zero, by increasing expiratory pressure if the measure of the degree of dynamic airway compression is large or increasing, and by reducing expiratory pressure if the measure of the degree of dynamic airway compression is small or zero.
The measure of the degree of dynamic airway compression may be an instantaneous or pointwise measure within any given breath, and the step of servo-controlling the measure to be zero may similarly be performed pointwise within a given breath, so that the expiratory pressure is similarly varied pointwise within a breath. As an alternative to thus basing the airway compression determination and the servo control on multiple airflow determinations made within each individual respiratory cycle, the derivation of the measure of the degree of dynamic airway compression and the servo-controlling of the airway compression may be performed across a plurality of respiratory cycles.
During expiration, the expiratory pressure increase may be linear as a function of expired volume as will be described below.
The measure of the degree of dynamic airway compression is preferably derived by measuring the airway conductance separately during the inspiratory and expiratory portions of one or more respiratory cycles, and calculating the measure of the degree of dynamic airway conductance as a function of the inspiratory conductance minus the expiratory conductance, or alternatively as the ratio of the inspiratory conductance to the expiratory conductance. The two separate conductances during inspiration and expiration may be measured by superimposing a high-frequency oscillation on the patient interface pressure, at a known or measured amplitude, identifying the inspiratory and expiratory portions of each respiratory cycle, measuring the component of the respiratory airflow at the high frequency separately over the inspiratory and expiratory portions of one or more respiratory cycles, and from these measurements and the determined pressure amplitude calculating the inspiratory airway conductance and the expiratory airway conductance.
Alternatively, the measure of the degree of dynamic compression may be derived from the shape of the expiratory airflow versus time curve. The measure is zero when the expiratory flow decays exponentially from the moment of the peak expiratory flow to end expiration, but is large when the expiratory flow decreases suddenly from the peak expiratory flow and is then steady but non-zero for the remainder of expiration. The measure may be the ratio of the mean expiratory flow during approximately the last 25% of expiratory time to the peak expiratory flow.
Further objects, features and advantages of the invention will become apparent upon consideration of the following detailed description in conjunction with the drawing which depicts illustrative apparatus for implementing the method of our invention.
DETAILED DESCRIPTION OF THE INVENTION
In the drawing, a blower 1 supplies breathable gas to a mask 2 in communication with a patient's airway via a delivery tube 3 and exhausted via an exhaust 4 . Airflow at the mask 2 is measured using a pneumotachograph 5 and a differential pressure transducer 6 . The mask flow signal from the transducer 6 is then sampled by a microprocessor 7 . Mask pressure is measured at the port 8 using a pressure transducer 9 . The pressure signal from the transducer 6 is then sampled by the microprocessor 7 . The microprocessor 7 sends an instantaneous mask pressure request (i.e., desired) signal to a servo 10 , which compares the pressure request signal with the actual pressure signal from the transducer 9 to control a fan motor 11 . Microprocessor settings can be adjusted via a serial port 12 .
It is to be understood that the mask could equally be replaced with a tracheotomy tube, endotracheal tube, nasal pillows, or other means of making a sealed connection between the air delivery means and the subject's airway.
The invention involves the steps performed by the microprocessor to determine the desired mask pressure. The microprocessor accepts the mask airflow and pressure signals, and from these signals determines the instantaneous flow through any leak between the mask and patient, by any convenient method. For example, the conductance of the leak may be estimated as the instantaneous mask airflow, low-pass filtered with a time constant of 10 seconds, divided by the similarly low-pass filtered square root of the instantaneous mask pressure, and the instantaneous leakage flow may then be calculated as the conductance multiplied by the square root of the instantaneous mask pressure. Respiratory airflow is then calculated as the instantaneous mask airflow minus the instantaneous leakage flow.
In the simple case of no intrinsic PEEP, the instantaneous pressure at the mask may be simply set as follows, in order to provide ventilatory support to the patient: P = P INSP flow > 0 ( inspiration ) P = P EXP flow < = 0 ( expiration )
where P EXP is less than or equal to P INSP . Typically, P EXP might be zero, and P INSP might be of the order of 10 to 20 cmH 2 O.
Two embodiments for deriving a measure of the degree of expiratory airflow limitation will now be considered. In the first embodiment, airway conductance during inspiration is compared with airway conductance during expiration, and a higher conductance during inspiration indicates expiratory airflow limitation. Airway conductance is calculated by superimposing on the instantaneous mask pressure a 4-Hz oscillation of amplitude 1 cmH 2 O, and measuring the component of the respiratory airflow signal at 4 Hz. The conductance may be calculated once for each half cycle of the 4-Hz oscillation. In order to identify inspiratory and expiratory halves of the respiratory cycle, the respiratory airflow is low-pass filtered to minimize the imposed 4-Hz oscillation, for example, by averaging measured respiratory airflow over a moving window of length 0.25 seconds. If the 4-Hz low-pass filtered flow is above a threshold such as 0.1 L/sec, it is taken to be the inspiratory half-cycle. Otherwise, it is taken as being the expiratory half-cycle.
Conductance over one or more inspiratory half-cycles, and over one or more expiratory half cycles is now calculated, using standard averaging or filtering techniques. The conductance during inspiration minus the conductance during expiration yields a first measure M 1 of the degree of dynamic airway compression. Preferably, M 1 can be normalized by dividing by the mean conductance over the entire breath or breaths, and a threshold value, for example, 0.2, can be subtracted so that only differences in conductance of 20% or more are regarded as indicative of dynamic airway compression. Thus, M 1 =(average conductance during inspiration−average conductance during expiration)/(average conductance over entire breath)−0.2.
Finally, it is necessary to adjust the expiratory pressure to servo-control the difference in conductance to be zero. This can be done for, example, by increasing P EXP by (0.1)(M 1 ) cmH 2 O per second. Using this method, if there is dynamic airway compression, P EXP will slowly increase until M 1 reaches zero, at which point there will be no further dynamic airway compression. Changes in the pressure required to prevent dynamic compression with the passage of time can be tracked. In an elaboration of this first embodiment, M 1 can be calculated as a function of the time into expiration, and the pressure at different points into expiration servo-controlled separately within a breath.
In the second embodiment for deriving a measure of the degree of expiratory airflow limitation, the degree of expiratory flow limitation is calculated from the shape of the expiratory flow versus time curve. The expiratory portion of each breath is identified, for example, by taking expiration as the period where airflow is less than 0.1 L/sec. The mean expiratory airflow during the final 25% of expiratory duration is calculated, and divided by the peak expiratory airflow. For a subject without expiratory airflow limitation, this ratio will be close to zero, and less than a threshold such as 0.2, whereas for a subject with expiratory airflow limitation, it will be larger, for example, in the range 0.2 to 0.6, with higher values indicating more severe dynamic airway compression. Therefore, a second measure of the degree of expiratory airflow limitation is M 2 =(mean expiratory flow during last 25% of expiratory time)/(peak expiratory flow)−threshold, where the threshold is, for example, 0.2.
In the final step in this second embodiment, if M 2 is positive, the expiratory pressure P EXP is increased slightly, for example by (0.1)(M 2 ) cmH 2 O per breath. Conversely, if M 2 is negative, P EXP is decreased slightly, for example, by (0.1)(M 2 ) cmH 2 O per breath.
A third embodiment, which can be used as an enhancement of the servo-controlling step in either of the above two embodiments, takes account of the fact that here is no dynamic compression at the start of expiration, and no external pressure is required to prevent dynamic compression at the start of expiration, but that dynamic compression develops as the elastic recoil decreases. Since the elastic recoil pressure decreases approximately linearly on expired volume, the external pressure required to be applied will increase approximately linearly as a function of expired volume. Therefore, in this third embodiment, expiratory pressure is set as:
P EXP ( t )= K V ( t )/ V T
where P EXP (t) is the pressure at time t in the expiratory portion of a respiratory cycle, V(t) is the expired volume at time t into the expiration, and V T is the tidal volume of the previous inspiration. Thus, V(t)V T increases from 0 to 1 during expiration. The constant K is adjusted in order to servo-control either M 1 , or M 2 to be zero, and will approximate PEEPi.
Although the invention has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the application of the principles of the invention. Numerous modifications may be made therein and other arrangements may be devised without departing from the spirit and scope of the invention. | The invention prevents dynamic airway compression during ventilatory support of a patient. The respiratory airflow is determined by measurement or calculation, and a measure of the degree of dynamic airway compression is derived from the determined airflow. This measure is servo-controlled to be zero by increasing expiratory pressure if the measure of the degree of dynamic airway compression is large or increasing, and by reducing expiratory pressure if the measure of the degree of dynamic airway compression is small or zero. | 0 |
FIELD OF THE INVENTION
The invention concerns a cocking device for a bolt mechanism.
BACKGROUND OF THE INVENTION
Such a cocking device is known from DE 42 23 498 C2. There, a cocking slider for the cocking and uncocking of a striker spring, which can be displaced between a rear uncocking position and a front cocking position, is located on a breech housing of a rifle. The cocking slider has an upper slider part, which projects upward from the breech housing, and a lower catch part with a catch, which is located in the breech housing. The catch of the cocking slider is intended to mesh with a mating catch, which is located firmly on the breech housing, to hold the cocking slider in the front cocking position. With this known cocking device, the cocking slider for the cocking of the striker spring on the upper slider part can be pushed forward and meshes into the corresponding mating catch on the breech housing, in the front cocking position, with its catch, provided on the rear end of the catch part. By pressing on the rear end of the slider part, it is possible to press out the catch from the mating catch, wherein the cocking slider again arrives at its rear uncocked position, with the uncocking of the striker spring.
SUMMARY OF THE INVENTION
The goal of the invention is to create a cocking device of the type mentioned in the beginning, which has an improved safety with respect to the unintended release of a shot.
This goal is attained by a cocking device as set forth in the claims. Appropriate developments and advantageous refinements of the invention are given in the subclaims.
In the cocking device in accordance with the invention, an uncocking mechanism for the automatic uncocking of the striker spring when a magazine is removed is correlated with the cocking slider. If the magazine is removed from a magazine well of the rifle or is not correctly inserted into the magazine well, then the cocking slider is automatically pushed into its retracted uncocked position and in this way, the striker spring is uncocked. With the removal or incorrect locking of the magazine, therefore, the striker spring is automatically uncocked and cannot be cocked into the cocking position even with a displacement of the cocking slider. Even if there is still a cartridge in the cartridge chamber, a shot cannot be released, wherein an increased safety of the rifle is attained.
In a particularly appropriate embodiment, the uncocking mechanism has a catch plate in the breech housing, which can displaced between a rear safety position and a front catch position, on which the mating catch for the catch of the cocking slider is located. If the catch plate is located in the rear safety position, the catch of the cocking slider in the front cocking position has no abutment, so that the striker spring cannot be cocked. The holding of the catch plate in the front catch position, with a properly inserted magazine or the release of the catch plate for the displacement into the rear safety position, with the removed or improperly inserted magazine, takes place via a blocking element, arranged as, for example, a blocking fork, which is located in the breech housing.
The blocking element is appropriately movable via an actuation mechanism, located in a system casing, between a lowered position for the holding of the catch plate in the front catch position and a raised position for the release of the catch plate for its displacement into the rear safety position.
The actuation mechanism appropriately comprises one or more pressure pins, arranged in a displaceable manner on a carrier; they can be moved upon insertion of the magazine, via rocker levers, into a retracted position, and upon removal of the magazine, via springs into an extended position to push the blocking element into the raised position for the release of the catch plate.
The blocking element is preferably designed as a blocking fork with a placement surface for a rear end surface of the catch plate and a passage for the catch plate located below the placement surface.
BRIEF DESCRIPTION OF THE DRAWINGS
Other special features and advantages of the invention can be deduced from the following description of a preferred embodiment example with the aid of the drawing. The figures show the following:
FIG. 1 , a partial view of a repeating rifle with an uncocked cocking device and a magazine inserted in the longitudinal section;
FIG. 2 , a partial view of the repeating rifle of FIG. 1 , with a cocked cocking device;
FIG. 3 , a partial view of a repeating rifle, with an uncocked cocking device, with the magazine removed;
FIG. 4 , a perspective view of the cocking device in an uncocked position, in accordance with FIG. 1 ;
FIG. 5 , an enlarged representation of the lower part of a cocking slider from the cocking device of FIGS. 1-4 ;
FIG. 6 , an enlarged representation of a catch plate from the cocking device of FIGS. 1-4 ; and
FIG. 7 , an enlarged representation of a blocking element from the cocking device of FIGS. 1-4 .
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1-3 show a part of a repeating rifle with a system casing 1 , a bolt mechanism 2 arranged in a displaceable manner on the system casing 1 , a rear shaft 3 affixed on the rear side of the system casing 1 , and a magazine 5 inserted in a magazine well 4 from the underside of the system casing 1 . In the embodiment example shown, the trigger guard 6 with the trigger 7 is located on the underside of the magazine 5 . The trigger guard 6 and the trigger 7 are therefore firmly connected to the magazine 5 in this embodiment, so that they remain on the magazine 5 even with the removal of the magazine 5 from the repeating rifle. If the magazine 5 is removed, then the trigger device can also no longer be actuated.
A striking pin 8 with a cocking piece 9 is located in the breech housing 2 . The cocking piece 9 is connected to a trigger mechanism—not shown in more detail here—which is located in the system casing 1 ; the trigger mechanisms cannot be actuated with an inserted magazine 5 , due to a projection 10 of the trigger 7 , which can be seen in FIG. 4 . There is also a locking chamber 11 with a locking element 12 , designed as an expansion sleeve, accommodated in the breech housing 2 .
A cocking slider with an upper cocking slider part 13 and a lower cocking slider part 14 , shown separately in FIG. 5 , is arranged in a displaceable manner between an uncocking position, shown in FIG. 1 , and a cocking position, shown in FIG. 2 , on the rear end of the breech housing 2 , descending at a slant toward the rear. The lower cocking slider part 14 is connected to a cocking pin 17 , located, in a displaceable manner, within the striking pin 8 , via a fork piece 15 and an articulated lever 16 . By displacement of the cocking pin 17 , with the aid of the cocking slider, a striker spring 48 , shown schematically in FIG. 3 , can be cocked or uncocked within the striking pin 8 .
From FIG. 5 , it is clear that the lower cocking slider part 14 has an upper area 18 , located in the upper cocking slider part 13 , a middle cross-link 19 , which is guided, in a displaceable manner, in a longitudinal slit of the breech housing 2 , and a lower catch cross-link 20 with a catch 21 , which is designed as a rear catch surface, at an incline. Via lateral pins 22 on the lower catch cross-link 20 , the lower cocking slider part 14 is connected to the fork piece 15 , in accordance with FIG. 4 . The catch 21 is intended for placement on an opposite mating catch 23 , at an incline, on the rear end of a longitudinal hole 24 in a catch plate 25 , shown in FIG. 6 .
The catch plate 25 , shown separately in FIG. 6 , lies on the lower catch cross-link 20 of the lower cocking slider part 14 and is guided by lateral projections 26 on the catch cross-link 20 . The catch plate 25 has a round end surface 27 on its rear end, for placement on a corresponding placement surface 28 of a blocking element 29 , shown in FIG. 7 .
The blocking element 29 , constructed here as a blocking fork, contains two parallel connecting pieces 30 , projecting downward, in accordance with FIG. 7 , with a slit-like passage 31 , located below the placement surface 28 , which has a somewhat larger width than the catch plate 25 .
Furthermore, a projection 32 with a placement surface 33 , which is rounded off inwardly, is provided on the upper side of the fork-like blocking element 29 .
As can be seen from FIGS. 1-4 , a carrier 34 with two vertically displaceable, parallel pressure pins 35 , which are acted on upwardly by pressure springs, is placed in the system casing 1 . The upper ends of the pressure pins 35 are intended for engagement with the lower ends of the two connecting pieces 30 of the blocking element 29 . Moreover, two rocker levers 36 , coupled with the pressure pins 35 , are placed laterally on the carrier 34 .
In FIG. 3 , one can see that the rocker levers 36 , which can swivel around axles 37 on the carrier 34 , have a rear end 38 , connected to the individual pressure pin 35 , and a front end 41 , which projects into a holding gap 39 , between the magazine well 4 and a front projection 40 on the carrier 34 . The rocker levers 36 are coupled with the pressure pins 35 in such a way that the upper ends of the pressure pins 35 are retracted upward into the carrier 34 by the swiveling of the front ends 41 of the rocker levers 36 , and are pushed downward by the swiveling of the front ends 41 of the rocker levers 36 , again upward via the force of the pressure springs, and thereby press the blocking element 29 upward into a raised position. The actuation of the rocker levers 36 takes place via the magazine 5 , whose upper border 42 meshes into the holder gap 39 in the incorporation position of the magazine 5 shown in FIG. 1 , and the front ends 41 of the rocker levers 36 are swiveled into the upper position, shown in accordance with FIG. 1 . In this way, the upper ends of the pressure pins 35 are retracted into the carrier 34 . If, on the other hand, the magazine 5 is removed in accordance with FIG. 3 , then the rocker levers 36 are again rotated back, via the pressure springs on the pressure pins 35 , so that the upper ends of the pressure pins 35 are again moved upward and the blocking element 29 is pushed into the raised position shown in accordance with FIG. 3 .
FIG. 4 shows that laterally elastic flaps 44 , with an upper locking lug 45 and a lower gripping part 46 , are placed on the side walls of a housing 43 of the magazine 5 . If the magazine 5 is correctly inserted into the magazine well, the locking lugs 45 mesh into indentations 47 , shown in accordance with FIG. 3 , on the lateral interior walls of the magazine well 4 . To remove the magazine 5 from the magazine well 4 , the two flaps 44 can be pressed together via the gripping parts 46 , which project downward, and in this way, the locking lugs 45 are moved out of the corresponding indentations 47 . With the removal of the magazine 5 , the cocking device is automatically uncocked, which is explained in more detail, below, with the aid of FIGS. 1-4 .
If the magazine 5 is found in the incorporation position, shown in accordance with FIG. 1 , and the locking lugs 45 mesh into the corresponding indentations 47 in the magazine well 4 , then the front ends 41 of the rocker levers 36 are pressed upward by the upper border 42 on the housing 43 of the magazine 5 . In this way, the two pressure pins 35 are pressed downward against the forces of the pressure springs located around them. The blocking element 29 , also acted on, downward, by a spring which is not depicted, is likewise found in a lower position and the catch plate 25 fits tightly, with its rear, round end surface 27 , on the corresponding placement surface 28 of the blocking element 29 . In the position shown in FIG. 1 , the cocking slider with the upper and lower cocking slider parts 13 and 14 is found in a lower uncocking position, in which the cocking pin 17 is retracted via the articulated lever 16 and the fork piece 15 , and the striker spring 48 , shown in FIG. 3 , is uncocked.
If the cocking slider with an inserted magazine 5 is pushed from the lower uncocking position, shown in FIG. 1 , into the cocking position, shown in accordance with FIG. 2 , by pressure on the upper cocking slider part 13 , and in this way, the cocking pin 17 is pushed forward via the articulated lever 16 and the fork piece 15 in order to cock the striker spring 48 , shown in FIG. 3 , the cocking slider can mesh by placement of the catch 21 on the mating catch 23 of the catch plate 25 , held by the blocking element 29 in the front catch position, as is shown in FIG. 2 . The bolt is cocked in this position in which the rear end of the upper cocking slider part 13 is raised slightly from the breech housing 2 .
To uncock the bolt, the only thing needed is to press on the rear end of the upper cocking slider part 13 . In this way, the catch 21 on the lower cocking slider part 14 is pressed out, downward, from the mating catch 23 of the catch plate 25 and the cocking slider is again pressed back into its uncocking position, shown in FIG. 1 , due to the effect of the striker spring 48 .
If, however, the magazine 5 is not inserted correctly or is taken out of the magazine well 4 , in accordance with FIG. 3 , the front ends 41 of the rocker levers 36 can move downward, and, in this way, the pressure pins 35 can move upward due to the effect of the pressure springs. The blocking element 29 is raised by the pressure pins 35 moving upward, wherein the rear end 27 of the catch plate 25 is lifted out of the mating catch 28 on the blocking element 29 , and the catch plate 25 arrives at a rear detachment position, shown in FIG. 3 , from the front catch position shown in FIG. 2 , together with the cocking slider, due to the effect of the striker spring 48 . The cocking pin 17 is also retracted via the fork piece 15 and the articulated lever 16 and the striker spring 48 is uncocked. With the removal of the magazine 5 , therefore, the striker spring 48 is automatically uncocked. Only when the magazine 5 is again properly inserted and locked can the catch plate 25 , dragged along by the cocking slider during the pushing up, again arrive for placement with its lower end surface 27 at the placement surface 28 of the blocking element 29 , which is then, once again, lowered, wherein a renewed cocking of the striker spring 48 is made possible. | The invention concerns a cocking device for a bolt mechanism with a cocking slider ( 13, 14 ), which can be displaced, on a breech housing ( 2 ), between a rear uncocking position and a front cocking position, for the cocking and uncocking of a striker spring and a catch ( 21 ), located on the cocking slider ( 13, 14 ), which works together with a mating catch ( 23 ) to hold the cocking slider ( 13, 14 ) in the front cocking position. In order to attain an improved safety with respect to an unintended release of a shot, an uncocking mechanism ( 25, 29 ) for the automatic uncocking of the striker spring ( 48 ), when the magazine ( 5 ) has been removed, is correlated with the cocking slider ( 13, 14 ). | 5 |
FIELD OF THE INVENTION
The present invention relates to a movable touchpad. More specially, the present invention relates to a movable touchpad for a laptop computer.
BACKGROUND OF THE INVENTION
For convenience of portability, a laptop computer usually has a touchpad near a keyboard to replace a mouse as an input device. Users are not limited to the environment where they use the laptop computer and free from inconvenience that the mouse has to be carried all the way. However, touchpads have defects such as low sensitivity and easy affection by environment. Most users would like to use a mouse rather than a touchpad.
A touchpad generally comprises two portions: a touch detecting unit and a touch control unit. The touch detecting unit is used for detecting and receiving touch control location data from users. Then, the touch control location data is sent to the touch control unit. By the touch control unit, the location data is converted into a coordinate. The coordinate is sent to an operating system (OS) of a computer to control location of a cursor. A common touchpad utilizes resistance, capacitance, infrared ray, or surface acoustic wave.
However, characteristics of the touchpad are easily influenced by change of the atmospheric pressure to affect operation sensitivity. For example, when the atmospheric pressure becomes lower, human body will lower its internal pressure to adapt to the change of the atmospheric pressure. It causes change of conductivity in the human body. When a capacitive touchpad is used, due to reduction of coupled capacitance formed between the human body and the touchpad, sensitivity of the touchpad decreases accordingly. Hence, users need to exert larger force. On the other hand, when the atmospheric pressure becomes higher, users merely need to exert smaller force.
As to a resistive touchpad, the principle thereof is pressure detection on the surface of the touchpad. After voltage transformation, the touch location can be calculated. When the atmospheric pressure becomes lower, users need to exert larger force. When the atmospheric pressure becomes higher, users merely need to exert smaller force.
Therefore, under different atmospheric pressures, operating sensitivity of the touchpad will be affected. It is inconvenient for users to change their habit and force in using the touchpad.
Touchpads have lower sensitivity in moving. When the sensitivity is increased, precise positioning can not be achieved. Sensitivity and positioning precision will be affected by user contact area. Additionally, when a current touchpad is used to move the cursor, fingers are needed to draw back and forth on the touchpad to move the cursor. When the cursor needs to be moved a longer distance, it is inconvenient for the fingers to draw back and forth many times.
Since traditional touchpads are easily influenced by the change of the environmental atmospheric pressure or sweats from the fingers to affect operation sensitivity and positioning precision, it is necessary to provide a touch control device having sensitivity irrespective of change of the environmental atmospheric pressure. Meanwhile, it can provide better control over sensitivity so that a laptop computer can control the cursor with high sensitivity without the aid of a mouse.
Therefore, in order to solve problems mentioned above, US Patent Publication No. 2008/0068332 provides a new touchpad device to control the cursor on the screen. Please refer to FIG. 1 . The invention uses a light source to scan a moving template and reflected light beams from the moving template to calculate movement and location of the cursor corresponding to displacement of the moving template. In addition, there is an automatic homing device for fixing the moving template in a certain point so that the template can be further used to control the cursor. However, the automatic homing device in this invention doesn't conform to usual practice. There is no detailed study on relation between cursor displacement speed and edge contacting time of the touchpad. It causes new problems and becomes more inconvenient.
SUMMARY OF THE INVENTION
In order to solve the problems and inconvenience in the prior art mentioned above, the present invention provides a movable touchpad for a computer. It has a slidable template for users to touch and move. It can also provide users with feeling of movement to control location of the cursor of the computer. There is a resistive or capacitive surface above the slidable template for providing users with click, double click or drag function on any location of the surface. Additionally, an optical detecting device is provided below the slidable template for detecting displacement optical speckle images of the back surface of the slidable template. The optical speckle images are continuously processed by an image processor. Relative displacement data are calculated and sent to the operating system of the computer for the operating system to control location of the cursor. Furthermore, the present invention also uses a edge detecting device. The edge detecting device not only provides a dynamic control over the cursor, but also calibrates the location of the cursor to synchronize the movement of the slidable template and the corresponding movement of the cursor.
By replacing a conventional capacitive or resistive touchpad with a slidable template to control movement of a cursor, it can avoid adverse influence on moving the touchpad caused by change of atmospheric pressure. Besides, an optical mechanism using invariant optical speckle imaging device and method with a slidable template has higher sensitivity and linearity. Thus, it doesn't need to move fingers back and forth frequently on the touchpad for achieving a long movement of a cursor. It can reduce fatigue of fingers. Accordingly, prevention of wrist injury caused by long time use of a mouse and finger injury caused by long time use of a traditional touchpad can be achieved by the present invention. Furthermore, a slidable template can provide users with good feeling like using a mouse.
In accordance with an aspect of the present invention, a highly sensitive movable touchpad for a digital apparatus having a cursor, includes: a slidable template having a front surface exposed and a back surface with a specific texture; a limiting member, for limiting the slidable template within a moving range and providing the slidable template with a low friction, surrounding the slidable template and exposing central portion of the front surface of the slidable template; an optical displacement detecting device, located below the slidable template, for detecting movement of the slidable template, including: a light source, for emitting light beams to illuminate the back surface of the slidable template; an image sensor for receiving speckle images formed by light beams scattered by the back surface; and an image processor for obtaining relative location, moving direction and speed of the slidable template by comparison of the speckle images; and a control unit for controlling corresponding movement of the cursor of the digital apparatus according to the relative location, moving direction and speed obtained from the image processor.
Preferably, the limiting member has an opening around central portion of the back surface of the slidable template for exposing the back surface to be illuminated by the light beams from the light source.
Preferably, the optical displacement detecting device further includes a lens for converting the light beams emitted from the light source into parallel light beams to illuminate the back surface of the slidable template.
Preferably, the optical displacement detecting device further includes an imaging module for receiving the scattered light beams and generating diffractive light beams.
Preferably, the imaging module includes an imaging lens and an aperture.
Preferably, the movable touchpad further includes a capacitive touch switch located on the slidable template for providing the slidable template with touch functions.
Preferably, the touch functions include single click, double click, drag and scroll.
Preferably, the movable touchpad further includes a resistive touch switch located on the slidable template for providing the slidable template with touch functions.
Preferably, the touch functions include single click, double click, drag and scroll.
Preferably, the front and back surfaces of the slidable template are form of an identical material.
Preferably, the front and back surfaces of the slidable template are form of different rigid materials.
Preferably, the slidable template is made of aluminum.
Preferably, the front and back surfaces of the slidable template have different surface characteristics.
Preferably, the surface characteristics include roughness and texture.
Preferably, the movable touchpad further includes a edge detecting device, provided at four sides of the limiting member, for detecting whether the slidable template reaches limit of the moving range.
Preferably, the edge detecting device includes a miniaturized touch switch, sensor or button switch.
Preferably, the edge detecting device provides a edge contact signal to the image processor for synchronizing the movement of the slidable template and the corresponding movement of the cursor.
Preferably, the edge contact signal is a digital pulse.
Preferably, the light source is a light emitting diode (LED) or laser diode (LD).
Preferably, the image processor is a central processing unit (CPU), field programmable gate array (FPGA), digital signal processor (DSP) or application-specific integrated circuit (ASIC).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a prior art of a touch control device.
FIG. 2 illustrates a touchpad of the present invention.
FIG. 3 illustrates a first embodiment of the present invention.
FIG. 4 illustrates a second embodiment of the present invention.
FIG. 5 illustrates another touchpad of the present invention.
FIG. 6 illustrates a third embodiment of the present invention.
FIG. 7 shows a relationship between cursor movement speed and contact time of the touchpad and the edge in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The goal of the present invention is to provide a highly sensitive movable touchpad. It can provide control over cursor with good sensitivity and touch control functions. The movable touchpad can be applied to laptop computers. It can also be applied to joysticks, remote controls and any interfaces using a cursor for browsing.
The present invention is illustrated in detailed by three embodiments.
First Embodiment
As shown in FIG. 2 and FIG. 3 , a movable touchpad comprises a slidable template 202 and a housing 204 . The slidable template 202 is provided in the housing 204 . The housing 204 has an upper opening on the top surface and a lower opening on the bottom surface. The upper opening is for fingers to touch. The slidable template 202 is movable and exposed externally via the upper opening of the housing 204 for users to use fingers to control movement. Please refer to FIG. 2 . FIG. 2 shows a longitudinal sectional view of the housing 204 and slidable template 202 (with central portion of the housing 204 omitted for easy understanding) in the upper portion of the figure and a top view thereof in the lower portion of the figure. The housing 204 has a space for accommodating the slidable template 202 . A main function of the housing 204 is to provide the slidable template 202 with a low sliding friction and limit moving range of the slidable template 202 . The moving range has the same aspect ratio as that of the screen. Hence, when the slidable template 202 moves in the limited moving range, the cursor can be moved to any point of the screen.
As shown in FIG. 3 , an optical displacement detecting device 206 is installed below the slidable template 202 for detecting displacement of the slidable template 202 . At the lower opening of the housing 204 , a light source 2061 (LED or LD) of the optical displacement detecting device 206 can be used to illuminate the back surface of the slidable template 202 .
The front surface of the slidable template 202 is formed with a material which provides users' fingers with comfortable touching feeling. The back surface of the slidable template 202 is advantageous to the optical displacement detecting device 206 for detecting displacement. For example, for a LED light source, the back surface is rough so as to be convenient for displacement calculation. However, for a laser light source, the back surface is well scattering so as to catch good contrast optical speckle images for calculating optical speckles displacement. Therefore, the slidable template 202 can be made of a single rigid material (for example, aluminum), composed rigid materials (front and back surfaces of the slidable template 202 having different materials), or any two materials having different surface characteristics (such as roughness and texture) in the front and back surfaces of the slidable template 202 , to satisfy the requirements that the front surface needs good feeling and the back surface needs to perform optical displacement detection.
Another function of the slidable template 202 is to prevent light beams from the light source 2061 from hurting human eyes.
In addition to the light source 2061 , the optical displacement detecting device 206 comprises a lens 2062 , an imaging lens 2063 , an aperture 2064 , an image sensor 2065 and an image processor 2066 . The imaging lens 2063 , aperture 2064 and image sensor 2065 form an optical detecting mechanism. The lens 2062 converts light beams from the light source 2061 into parallel light beams and send the parallel light beams to the back surface of the slidable template 202 , and scattered light beams are generated. The imaging module composed of the imaging lens 2063 and aperture 2064 is used to receive scattered light beams and generate several diffractive light beams. After the light beams emitted from the light source 2061 are illuminated to the back surface of the slidable template 202 via the lens 2062 , the imaging lens 2063 and aperture 2064 will form shadows and optical speckles of the back surface of the slidable template 202 onto the image sensor 2065 for converting the received optical speckles into imaging signals. Later, the imaging signals representing continuous movement of the optical speckles are sent to the image processor 2066 to obtain a displacement signal of the slidable template 202 . The displacement signal is sent to a driver of a computer 208 for providing location control to the cursor. The image processor 2066 is in charge of imaging processing and displacement calculation. It generates location data with respect to the slidable template 202 according to the received optical speckles. Relative location, moving direction and speed of the slidable template 202 can be obtained according to the location data. The image processor 2066 is a central processing unit (CPU), field programmable gate array (FPGA), digital signal processor (DSP) or application-specific integrated circuit (ASIC).
Second Embodiment
As shown in FIG. 4 , most elements and their functions of the present embodiment are the same as those in FIG. 3 . A movable touchpad of the second embodiment has a slidable template 302 , a housing 304 , and an optical displacement detecting device 306 (including a light source 3061 , a lens 3062 , an imaging lens 3063 , an aperture 3064 , an image sensor 3065 and an image processor 3066 ). Members having like functions will be identified by like reference numerals and overlapping descriptions will be omitted. In this embodiment, the slidable template 302 is a combination of different rigid materials. The back surface of the slidable template 302 is used as an optical blocker and a detected surface for the optical displacement detecting device 306 .
The front surface of the slidable template 302 is provided with a capacitive or resistive touch switch 3022 . When an object, such as a finger, touches the touch switch 3022 , a touch detection signal will be sent to the image processor 3066 of the optical displacement detecting device 306 . In addition to image processing and displacement calculation, the image processor 3066 performs detection of touch detection signal and determination of the kind of cursor functions, such as single click, double click, drag or scroll. Then, the image processor 3066 sends the detected displacement signal as mentioned in the first embodiment and touch detection signal to a driver of a computer 308 to provide cursor location control and cursor functions.
Third Embodiment
A slidable template is equally partitioned into several regions which are mapped correspondingly to various portions of the screen. Users control displacement and direction of movement of the slidable template to map the movement of the slidable template to the movement of the cursor on the screen. Since the slidable template is confined in a limited moving range, in order to have a better dynamic control for the cursor, such as gaming control, a edge detecting device is incorporated.
The edge detecting device can be a miniaturized touch switch, sensor, button switch or I/O contacts. It provides a edge contact signal which can be a digital pulse. The edge detecting device detects contact time of the slidable template and the edge detecting device.
Please refer to FIG. 5 and FIG. 6 . A left edge detecting device 4052 , a right edge detecting device 4054 , a top edge detecting device 4056 and a bottom edge detecting device 4058 are installed at the left, right, top and bottom sides (seen from the top view) inside a housing 404 . The edge detecting devices are to detect whether a slidable template 402 contacts edges of the moving range or not. When the slidable template 402 contacts the edges, an image processor 4066 of an optical displacement detecting device 406 will receive a edge contact signal. The optical displacement detecting device 406 includes a light source 4061 , a lens 4062 , an imaging lens 4063 , an aperture 4064 , the image sensor 4065 and the image processor 4066 . Members having like functions are identified by like reference numerals and overlapping descriptions will be omitted. The edge contact signal is a digital pulse. The slidable template 402 holds stationary after it contacts the edge detecting device. While the slidable template 402 is stationary, the image processor 4066 will keep receiving the digital pulses to determine stationary status and contact time of the slidable template 402 . Now, in order to ensure that the cursor moves in synchronization with the slidable template 402 to the edge of the screen, the image processor 4066 reports an predicted moving speed of the cursor to a computer 408 to cause the cursor to contact the edge of the screen while the slidable template 402 is stationary.
As shown in FIG. 7 , the abscissa represents contact time (t) of the slidable template 402 and the edge and the ordinate represents movement speed (v) of the cursor. Time t is set to zero while the slidable template 402 first contacts the edge detecting device. Segment (a) represents a situation where 0≦t≦T 1 and the computer 408 controls the cursor to move to the edge at a constant speed V. Segment (b) represents a situation where T 1 ≦t≦T 2 and moving speed of the cursor will increase linearly. It can also increase exponentially as Segment (c). When t≧T 2 , the speed drops to zero as Segment (d). Before the cursor arrives at the screen edge, location of the cursor is calculated by the image processor 4066 and the image processor 4066 sends out predicted displacement data. After the cursor arrives at the screen edge, the speed drops to zero and the cursor stops moving. Values of time T 1 , time T 2 , speed V, slope of Segment (b) and curvature of the Segment (c) can be set by a configuration program of the computer 408 , and sent to the image processor 4066 .
Furthermore, users can also decide to adopt Segment (a), (b) or (c). For example, when T 1 =0 and T 2 ≠0, Segment (a) is not applicable, and only Segment (b) or (c) is workable. When T 1 ≠0 and T 1 =T 2 , only Segment (a) is workable. When T 1 =T 2 =0, the cursor arrives at the screen edge if the slidable template contacts the edge, and no movement of the cursor can be seen.
The edge detecting devices can provide not only dynamic control over the cursor, but also adjustment for the location of the cursor to synchronize movement of the slidable template with that of the cursor on the screen.
The present invention is not limited to the embodiments above. For example, the moveable touchpad of the second embodiment can be integrated with that of the third embodiment.
While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures. | A highly sensitive movable touchpad is disclosed in the present invention. It is used for laptop computers and has a slidable template for users to move so that a cursor can be controlled by the touchpad. A resistive or capacitive detecting surface can be applied for detecting users' click, double click, drag, or scroll motion on any point of the surface. Additionally, there is an optical displacement sensor provided under the slidable template for detecting surface information on the back surface of the slidable template. A sequence of images of surface movement are processed by an image processing unit. Then, relative movement information is calculated and sent to an operating system in the computer. The operating system controls the cursor with the relative movement information. The present invention uses edge detectors for dynamically controlling the cursor and calibrating location of the cursor so that positioning of the touchpad is synchronous with the cursor. | 6 |
TECHNICAL FIELD OF THE INVENTION
The present invention is generally directed to distributed architecture routers and, in particular, to an apparatus and method using cognitive identical code to distribute control and management plane functions (or operations) between control processors of a multiprocessor router.
BACKGROUND OF THE INVENTION
There has been explosive growth in Internet traffic due to the increased number of Internet users, various service demands from those users, the implementation of new services, such as voice-over-IP (VoIP) or streaming applications, and the development of mobile Internet. Conventional routers, which act as relaying nodes connected to sub-networks or other routers, have accomplished their roles well, in situations in which the time required to process packets, determine their destinations, and forward the packets to the destinations is usually smaller than the transmission time on network paths. More recently, however, the packet transmission capabilities of high-bandwidth network paths and the increases in Internet traffic have combined to outpace the processing capacities of conventional routers.
This has led to the development of a new generation of massively parallel, distributed architecture routers. A distributed architecture router typically comprises a large number of routing nodes that are coupled to each other via a plurality of switch fabric modules and an optional crossbar switch. Each routing node has its own routing (or forwarding) table for forwarding data packets via other routing nodes to a destination address.
When a data packet arrives in a conventional routing node, a forwarding engine in the routing node uses forwarding tables to determine the destination of the data packet. A conventional Internet Protocol (IP) router uses a dedicated forwarding table for each type of traffic, such as Internet Protocol version 4 (IPv4), Internet Protocol version 6 (IPv6) and MPLS.
Conventional routers use many packet processors to route data traffic through the router. However, conventional routers typically use a single control plane processor to perform control plane functions (or operations) and management plane functions (or operations). The single control plane processor handles all management functions and all routing protocols. Some prior art routers may use two control plane processors, a primary and a secondary, for redundancy purposes. But each of these processors performs the same functionality. The primary control processor performs all control and management functions, while the secondary control processor is idle and waits for a failure of the primary control processor. Thus, the redundant processors are not used to increase the aggregate processing power and do not allow optimization of resource utilization through resource allocation.
Thus, the speed of control plane processing in prior art routers is limited by the processing power of a single processor. This fails to take advantage of parallel processing opportunities. To achieve high route update rates, expensive data processors must be used.
Therefore, there is a need in the art for improved high-speed routers. In particular, there is a need for a high-speed router in which control and management plane functions are not bottlenecked by a single control plane processor.
SUMMARY OF THE INVENTION
The present invention supports distribution of control plane functions (or operations) between the inbound and outbound network processors of a routing node, allows flexible resource allocation, uses standard protocols and operating system software, and provides a software solution with no additional hardware support.
In an advantageous embodiment, the present invention uses standard Linux sockets and standard protocols, such as TCP and UDP, to allow cognizant, but identical, control and management plane code to run in both the inbound and outbound network processors. This allows the distribution of management and routing functions (or operations) between these two processors, thereby allowing more aggregate processing power to be applied to the control plane functions and to allow splitting the workload between these processors as necessary to meet the control plane throughput requirements.
To address the above-discussed deficiencies of the prior art, it is a primary object of the present invention to provide a router for interconnecting external devices coupled to the router. According to an advantageous embodiment of the present invention, the router comprises: 1) a switch fabric; and 2) a plurality of routing nodes coupled to the switch fabric, wherein each of the plurality of routing nodes comprises i) packet processing circuitry capable of exchanging data packets with external devices and exchanging data packets with other ones of the plurality of routing nodes via the switch fabric and ii) control processing circuitry capable of performing control and management functions. The control processing circuitry comprises: i) a first network processor capable of performing control and management functions associated with the router; and ii) a second network processor capable of performing the control and management functions associated with the router, wherein the control and management functions are dynamically allocated between the first network processor and the second network processor.
According to one embodiment of the present invention, the control and management functions are dynamically allocated between the first network processor and the second network processor according to a first level of activity of control and management functions in the first network processor relative to a second level of activity of control and management functions in the second network processor.
According to another embodiment of the present invention, the first network processor is controlled by first control software code and the second network processor is controlled by second control software code substantially identical to the first control software code.
According to still another embodiment of the present invention, the first network processor determines a first group of control and management functions allocated to the first network processor by examining a configuration register associated with the first network processor.
According to yet another embodiment of the present invention, the second network processor determines a second group of control and management functions allocated to the second network processor by examining a configuration register associated with the second network processor.
According to a further embodiment of the present invention, a first one of the control and management functions may be re-allocated from the first group of control and management functions to the second group of control and management functions by modifying the contents of the first configuration register and the second configuration register.
Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:
FIG. 1 illustrates an exemplary distributed architecture router, which distributes forwarding table lookup operations across a plurality of microengines and threads according to the principles of the present invention;
FIG. 2 illustrates selected portions of the exemplary router according to one embodiment of the present invention;
FIG. 3 illustrates the inbound network processor and outbound network processor according to an exemplary embodiment of the present invention; and
FIG. 4 illustrates the inbound network processor and outbound network processor in greater detail according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 through 4 , discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged packet switch or router.
FIG. 1 illustrates exemplary distributed architecture router 100 , which distributes control and management plane functions across a plurality of processors according to the principles of the present invention. Router 100 supports Layer 2 switching and Layer 3 switching and routing. Thus, router 100 functions as both a switch and a router. However, for simplicity, router 100 is referred to herein simply as a router. The switch operations are implied.
According to the exemplary embodiment, router 100 comprises N rack-mounted shelves, including exemplary shelves 110 , 120 , and 130 , that are coupled via crossbar switch 150 . In an advantageous embodiment, crossbar switch 150 is a 10 Gigabit Ethernet (10 GbE) crossbar operating at 10 gigabits per second (Gbps) per port.
Each of exemplary shelves 110 , 120 and 130 may comprise route processing modules (RPMs) or Layer 2 (L 2 ) modules, or a combination of route processing modules and L 2 modules. Route processing modules forward data packets using primarily Layer 3 information (e.g., Internet protocol (IP) addresses). L 2 modules forward data packets using primarily Layer 2 information (e.g., medium access control (MAC) addresses). In the exemplary embodiment shown in FIG. 1 , only shelf 130 is shown to contain both route processing (L 3 ) modules and L 2 modules. However, this is only for the purpose of simplicity in illustrating router 100 . Generally, it should be understood that many, if not all, of the N shelves in router 100 may comprise both RPMs and L 2 modules.
Exemplary shelf 110 comprises a pair of redundant switch modules, namely primary switch module (SWM) 114 and secondary switch module (SWM) 116 , a plurality of route processing modules 112 , including exemplary route processing module (RPM) 112 a, RPM 112 b, and RPM 112 c, and a plurality of physical media device (PMD) modules 111 , including exemplary PMD modules 111 a, 111 b, 111 c, 111 d, 111 e, and 111 f. Each PMD module 111 transmits and receives data packets via a plurality of data lines connected to each PMD module 111 .
Similarly, shelf 120 comprises a pair of redundant switch modules, namely primary SWM 124 and secondary SWM 126 , a plurality of route processing modules 122 , including RPM 122 a, RPM 122 b, and RPM 122 c, and a plurality of physical media device (PMD) modules 121 , including PMD modules 121 a - 121 f. Each PMD module 121 transmits and receives data packets via a plurality of data lines connected to each PMD module 121 .
Additionally, shelf 130 comprises redundant switch modules, namely primary SWM 134 and secondary SWM 136 , route processing module 132 a, a plurality of physical media device (PMD) modules 131 , including PMD modules 131 a and 131 b, and a plurality of Layer 2 (L 2 ) modules 139 , including L 2 module 139 a and L 2 module 139 b. Each PMD module 131 transmits and receives data packets via a plurality of data lines connected to each PMD module 131 . Each L 2 module 139 transmits and receives data packets via a plurality of data lines connected to each L 2 module 139 .
Router 100 provides scalability and high-performance using up to M independent routing nodes (RN). A routing node comprises, for example, a route processing module (RPM) and at least one physical medium device (PMD) module. A routing node may also comprise an L 2 module (L 2 M). Each route processing module or L 2 module buffers incoming Ethernet frames, Internet protocol (IP) packets and MPLS frames from subnets or adjacent routers. Additionally, each RPM or L 2 M classifies requested services, looks up destination addresses from frame headers or data fields, and forwards frames to the outbound RPM or L 2 M. Moreover, each RPM (or L 2 M) also maintains an internal routing table determined from routing protocol messages, learned routes and provisioned static routes and computes the optimal data paths from the routing table. Each RPM processes an incoming frame from one of its PMD modules. According to an advantageous embodiment, each PMD module encapsulates an incoming frame (or cell) from an IP network (or ATM switch) for processing in a route processing module and performs framing and bus conversion functions.
Incoming data packets may be forwarded within router 100 in a number of different ways, depending on whether the source and destination ports are associated with the same or different PMD modules, the same or different route processing modules, and the same or different switch modules. Since each RPM or L 2 M is coupled to two redundant switch modules, the redundant switch modules are regarded as the same switch module. Thus, the term “different switch modules” refers to distinct switch modules located in different ones of shelves 110 , 120 and 130 .
In a first type of data flow, an incoming data packet may be received on a source port on PMD module 121 f and be directed to a destination port on PMD module 131 a. In this first case, the source and destination ports are associated with different route processing modules (i.e., RPM 122 c and RPM 132 a ) and different switch modules (i.e., SWM 126 and SWM 134 ). The data packet must be forwarded from PMD module 121 f all the way through crossbar switch 150 in order to reach the destination port on PMD module 131 a.
In a second type of data flow, an incoming data packet may be received on a source port on PMD module 121 a and be directed to a destination port on PMD module 121 c. In this second case, the source and destination ports are associated with different route processing modules (i.e., RPM 122 a and RPM 122 b ), but the same switch module (i.e., SWM 124 ). The data packet does not need to be forwarded to crossbar switch 150 , but still must pass through SWM 124 .
In a third type of data flow, an incoming data packet may be received on a source port on PMD module 111 c and be directed to a destination port on PMD module 111 d. In this third case, the source and destination ports are associated with different PMD modules, but the same route processing module (i.e., RPM 112 b ). The data packet must be forwarded to RPM 112 b, but does not need to be forwarded to crossbar switch 150 or to switch modules 114 and 116 .
Finally, in a fourth type of data flow, an incoming data packet may be received on a source port on PMD module 111 a and be directed to a destination port on PMD module 111 a. In this fourth case, the source and destination ports are associated with the same PMD module and the same route-processing module (i.e., RPM 112 a ). The data packet still must be forwarded to RPM 112 a, but does not need to be forwarded to crossbar switch 150 or to switch modules 114 and 116 .
FIG. 2 illustrates selected portions of exemplary router 100 in greater detail according to one embodiment of the present invention. FIG. 2 simplifies the representation of some of the elements in FIG. 1 . Router 100 comprises PMD modules 210 and 250 , route processing modules 220 and 240 , and switch fabric 230 . PMD modules 210 and 250 are intended to represent any of PMD modules 111 , 121 , and 131 shown in FIG. 1 . Route processing modules 220 and 240 are intended to represent any of RPM 112 , RPM 122 , and RPM 132 shown in FIG. 1 . Switch fabric 230 is intended to represent crossbar switch 150 and the switch modules in shelves 110 , 120 and 130 in FIG. 1 .
PMD module 210 comprises physical (PHY) layer circuitry 211 , which transmits and receives data packets via the external ports of router 100 . PMD module 250 comprises physical (PHY) layer circuitry 251 , which transmits and receives data packets via the external ports of router 100 . RPM 220 comprises inbound network processor (NP) 221 , outbound network processor (NP) 223 , and medium access controller (MAC) layer circuitry 225 . RPM 240 comprises inbound network processor (NP) 241 , outbound network processor (NP) 243 , and medium access controller (MAC) layer circuitry 245 .
Each network processor comprises a plurality of microengines capable of executing threads (i.e., code) that forward data packets in router 100 . Inbound NP 221 comprises N microengines (μEng.) 222 and outbound NP 223 comprises N microengines (μEng.) 224 . Similarly, inbound NP 241 comprises N microengines (μEng.) 242 and outbound NP 243 comprises N microengines (μEng.) 244 .
Two network processors are used in each route-processing module to achieve high-speed (i.e., 10 Gbps) bi-directional operations. Inbound network processors (e.g., NP 221 , NP 241 ) operate on inbound data (i.e., data packets received from the network interfaces and destined for switch fabric 230 ). Outbound network processors (e.g., NP 223 , NP 243 ) operate on outbound data (i.e., data packets received from switch fabric 230 and destined for network interfaces).
According to an exemplary embodiment of the present invention, each network processor comprises N=16 microengines that perform data plane operations, such as data packet forwarding. Each RPM also comprises a single RISC processor (not shown) that performs control plane operations, such as building forwarding (or look-up) tables. According to the exemplary embodiment, each microengine supports eight threads. At least one microengine is dedicated to reading inbound packets and at least one microengine is dedicated to writing outbound packets. The remaining microengines are used for forwarding table lookup.
In order to meet the throughput requirements for line rate forwarding at data rates up to 10 Gbps, it is necessary to split the data plane processing workload among multiple processors, microengines, and threads. The first partitioning splits the workload between two network processors—one operating on inbound data packets from the network interfaces to the switch and the other operating on outbound data packets from the switch to the network interfaces. Each of these processors uses identical copies of the forwarding table from its own memory space. This eliminates memory contention problems.
According to the principles of the present invention, the control and management plane functions (or operations) of router 100 may be distributed between inbound (IB) network processor 221 and outbound network processor 223 . The architecture of router 100 allows distribution of the control and management plane functionality among many processors. This provides scalability of the control plane in order to handle higher control traffic loads than traditional routers having only a single control plane processor. Also, distribution of the control and management plane operations permits the use of multiple low-cost processors instead of a single expensive processor. For simplicity in terminology, control plane functions (or operations) and management plane functions (or operations) will hereafter be collectively referred to as control plane functions.
FIG. 3 illustrates inbound network processor 221 and outbound network processor 223 according to an exemplary embodiment of the present invention. Inbound (IB) network processor 221 comprises control plane processor 310 , microengine(s) 222 , and configuration registers 315 . Outbound (OB) network processor 223 comprises control plane processor 320 , microengine(s) 224 , and configuration registers 325 . Inbound network processor 221 and outbound network processor 223 are coupled to shared memory 350 , which stores forwarding table information, including forwarding vectors and trie tree search tables.
Control and management messages may flow between the control and data planes via interfaces between the control plane processors and data plane processors. For example, control plane processor 310 may send control and management messages to the microengines 222 and control plane processor 320 may send control and management messages to the microengines 224 . The microengines can deliver these packets to the local network interfaces or to other RPMs for local consumption or transmission on its network interfaces. Also, microengines may detect and send control and management messages to their associated control plane processor for processing. For example, microengines 222 may send control and management plane messages to control plane processor 310 and microengines 224 may send control and management messages to control plane processor 320 .
Inbound network processor 221 operates under the control of control software stored in memory 330 , such as cognitive code 335 . Similarly, outbound network processor 223 operates under the control of control software stored in memory 340 , such as cognitive code 345 . According to the principles of the present invention, cognitive code 335 and cognitive code 345 are identical software loads.
Network processors 221 and 223 in router 100 share routing information in the form of aggregated routes stored in shared memory 350 . Network processors 221 and 223 are interconnected through Gigabit optical links to the switch modules (SWMs). Multiple SWMs can be interconnected through 10 Gbps links via Rack Extension Modules (REXMs). The management and routing functions/operations of router 100 are implemented in inbound network processor 221 and outbound network processor 223 in each RPM of router 100 .
In order to meet the bi-directional 10 Gbps forwarding throughput of the RPMs, two network processors—one inbound and one outbound—are used in each RPM. Inbound network processor 221 handles inbound (IB) packets traveling from the external network interfaces to switch fabric 230 . Outbound network processor 223 handles outbound (OB) packets traveling switch fabric 230 to the external network interfaces. In an exemplary embodiment of the present invention, control plane processor (CCP) 310 comprises an XScale core processor (XCP) and microengines 222 comprise sixteen microengines. Similarly, control plane processor (CCP) 320 comprises an XScale core processor (XCP) and microengines 224 comprise sixteen microengines.
The primary management and control plane functions of router 100 are management via Command Line Interface (CLI), management via Simple Network Management Protocol (SNMP), Standard Routing and Label Distribution Protocols, Internal Route Distribution using a proprietary protocol, and Forwarding Table Management (FTM). These functions can run in either inbound network processor 221 or outbound network processor 223 , or in both.
According to the principles of the present invention, control functions/operations may be distributed between inbound network processor 221 and outbound network processor 223 because both processors execute identical cognitive code, namely cognitive code 335 and cognitive code 345 . Each of inbound network processor 221 and outbound network processor 223 determines whether it is the inbound or outbound network processor by examining configuration register 315 and configuration register 325 , respectively. Configuration files allow each processor to determine the functions (or operations) mapped to it and its role relative to those functions, typically a master role or a slave role. Thus, each one of inbound network processor 221 and outbound network processor 223 becomes cognitive of its position in the system and its role. Use of a single software load for both processors reduces the number of separate software loads that must be managed, thus reducing configuration management complexity.
FIG. 4 illustrates inbound network processor 221 and outbound network processor 223 in greater detail according to an exemplary embodiment of the present invention. The primary management and control plane functions performed by control plane processors 310 and 320 are illustrated in FIG. 4 , along with the interfaces between network processors 221 and 223 that facilitate the distribution of the functions.
As can be seen in FIG. 4 , all of the major functions may be distributed across inbound network processor 221 and outbound network processor 223 . In inbound network processor 221 , the major functions comprise Simple Network Management Protocol (SNMP) manager 410 , Command Line Interface (CLI) manager 415 , standard Routing Protocols, Label Distribution Protocols, and Proprietary protocols manager 420 , Routing Information Base (RIB) manager 425 , Address Resolution Protocol (ARP) manager 430 , Neighbor Discovery Protocol (NDP) manager 435 , and Forwarding Table (FT) manager 440 . In Outbound network processor 223 , the major functions comprise Simple Network Management Protocol (SNMP) manager 460 , Command Line Interface (CLI) manager 465 , standard Routing Protocols, Label Distribution Protocols, and Proprietary protocols manager 470 , Routing Information Base (RIB) manager 475 , Address Resolution Protocol (ARP) manager 480 , Neighbor Discovery Protocol (NDP) manager 485 , and Forwarding Table (FT) manager 490 . According to the exemplary embodiment, inbound network processor 221 and outbound network processor 223 communicate via sockets 401 - 408 and sockets 451 - 458 .
According to an advantageous embodiment of the present invention, router 100 may use the control function partitioning shown in TABLE 1.
TABLE 1
FUNCTION
MASTER
SLAVE
SNMP
OB NP 223
IB NP 221
CLI
OB NP 223
IB NP 221
RP, LDF, prop.
IB NP 221
OB NP 223
FTM
IB NP 221
OB NP 223
This configuration distributes the management functions to outbound network processor (OB NP) 223 and the routing protocol and forwarding table manager functions to inbound network processor (IB NP) 221 . However, this partitioning of functionality can easily be changed by re-configuring configuration registers 315 and 325 .
SNMP agent functions operate on OB NP 223 , with processes in IB NP 221 providing SWM and Network Interface communication functions, as well as SMUX Peers or AgentX Servers to complete commands relating to the functionality of IB NP 221 . VTYSH Subagent functions associated with CLI operate on OB NP 223 , with IB NP 221 providing SWM and Network Interface communications functions, as well as VTYSH Servers to complete commands relating to the functions of IB NP 221 . RP, LDP, and proprietary protocols operate on IB NP 221 , with OB NP 223 providing Network Interface and SWM communications functions. Routes learned by OB NP 223 are sent to IB NP 221 for processing and FTM building. IB NP 221 builds the tables used by the microengines of both IB NP 221 and OB NP 223 . OB NP 223 maintains Forwarding Descriptors in local memory, as commanded by IB NP 221 .
In router 100 , IB NP 221 receives data from the network interfaces and sends data to the switch modules, but cannot send data to the network interfaces and cannot receive data from the switch modules. OB NP 223 receives data from the switch module and sends data to the network interfaces, but cannot send data to the switch modules and cannot receive data from the network interfaces. Due to this asymmetrical communication scheme, inter-processor communications are required so that both processors may participate in all major control functions.
IB NP 221 and OB NP 223 communicate using standard Linux sockets 401 - 408 and 451 - 458 . Standard IP protocols, such as User Datagram Protocol (UDP) or Transmission Control Protocol (TCP) are used on these communications links. Routing, label, forwarding, and management information are exchanged over these links.
TABLE 2 below lists the threads applicable to all distributed control functions. These threads run in both IB NP 221 and OB NP 223 . The distribution of functions may be scaled to more than two network processors by including additional pairs of In and Out Services Sockets, along with associated threads and queues for each additional processor.
TABLE 2
THREAD
FUNCTION
T-Main State Loop
Initialize and control all threads
T-Collector
Communicate with higher layer protocols
T-Reader
Read data from the other NP through the socket
interface. There are copies of this for both
Incoming and Outgoing Services
T-Writer
Write data to the other NP through the socket
interface. There are copies of this thread
for both the Incoming and the Outgoing
Services.
The main loop is a state machine (T-Main State Loop) that controls the other functional threads and the communication channels. The T-Collector thread receives data from higher level protocols through a pipe and delivers it to the functional module (e.g., FT manager 440 , 490 ). The functional distribution model allows each network processor to request services from the other network processor. The local network processor receives requests for services from the remote network processor via the In Services Socket and sends requests for services to the remote NP via the Out Services Socket.
There are read (T-Reader) threads and write (T-Writer) threads associated with each of the sockets. In the case of Incoming Services, requests are received from the remote network processor via the associated T-Reader thread and responses to the requests are sent to the remote network processor via the T-Writer thread. The remote processor initiates transactions through the In Services Socket. In the case of Outgoing Services, requests are sent to the remote network processor via the associated T-Writer thread and responses to the requests are received from the remote network processor via the T-Reader thread. The local processor initiates transactions through the Out Services Socket.
This invention enables smaller, cheaper network processors to be used in parallel to achieve higher control plane throughput. The exemplary embodiment described herein uses two network processors, but could be expanded to more processors and does not require specialized network processors. This present invention may be used to provide high control plane processing power at a relatively low cost, thus allowing cheaper, higher performance routers to be built.
Although the present invention has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims. | A router for interconnecting external devices. The router comprises a switch fabric and a plurality of routing nodes coupled to the switch fabric. Each routing node comprises packet processing circuitry for transmitting data packets to, and receiving data packets from, the external devices and for transmitting data packets to, and receiving data packets from, other routing nodes via the switch fabric and control data processing circuitry capable of performing control and management functions. The control data processing circuitry comprises a first network processor for performing control and management functions associated with the router and a second network processor for performing control and management functions associated with the router. The control and management functions are dynamically allocated between the first network processor and the second network processor. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 61/585,733, filed on Jan. 12, 2012 and U.S. Provisional Application No. 61/621,794 filed Apr. 9, 2012, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to novel constructions for injection pipe joints.
[0003] Injection joints for coupling pipes are known for instance from U.S. Pat. No. 3,920,787, U.S. Pat. No. 3,920,268, U.S. Pat. No. 4,523,779, U.S. Pat. No. 5,486,024, U.S. Pat. No. 7,341,285, and published applications US 2006/0191623, US 2010/0259040 and JP 05-346189. In injection pipe joints an adhesive is injected via a hole in the socket into a gap between a socket and an inserted pipe end and allowed to set after the socket and pipe end have been initially fitted together.
[0004] In some of the injection joint designs the mouth of the socket is capped by an annular flange ring fitting that closes the gap between the socket and the pipe end. Such flange ring fittings also serve to center the axis of the socket and pipe inserted into the socket. However, they are not reliably retained in position during adhesive injection unless they are clamped during injection and sometimes until the adhesive has fully cured.
[0005] The injection joint systems have the advantage that substantially 100% solids adhesive can be used putting the joint under less shrinkage stress than solvent adhesives, there is lower worker and environmental emission, and in many cases a wider range of pipe materials can be successfully mated. However, a difficulty in establishing an injection joint system is that most pipe end and socket joints are designed for use with solvent cement systems which have gaps that are too narrow to provide effective injection of most adhesives. It is difficult to supplant an existing system if pipe specifications have to be rewritten and/or sockets redesigned, or if there are significant increases in labor time to modify current commercial pipes and/or sockets to implement an injection joint.
[0006] It would be desirable to provide an injection joint system that can use existing pipe specifications and yet provides the desired gap properties. It would also be desirable to simplify the process to reduce the time needed to form an injection joint from existing pipe and fittings so that it effectively can compete with existing pipe joint systems.
SUMMARY OF THE INVENTION
[0007] The invention pertains to an injection joint that is more easily adapted to implementation with existing pipe and socket joint designs.
[0008] In some aspects the invention pertains to improved flange ring for an injection joint which includes an injection port. The injection port communicates with a channel which opens to the socket/pipe gap when assembled. The channel distributes adhesive to a gap between the pipe end and socket. The channel may be formed as a recess or slot in the inner wall of the ring.
[0009] Further aspects pertain to a flange ring for an injection joint that is slit longitudinally to split the ring. In some embodiments the flange ring includes both an injection port and a longitudinal slit spaced circumferentially apart from the injection port in the circumferential direction. The slit provides an exit port for the adhesive. The slit also facilitates mounting of the ring on the pipe in some embodiments in which the flange ring is sized to fit into a recess in the outer wall of the pipe end.
[0010] Further aspects pertain to a method of forming an injection pipe joint comprising providing a pipe end with a bottom and a circumferential recess spaced upwardly from the bottom, fitting a flange ring having an inner wall, outer wall and an axially directed slit between the inner and outer walls, onto the pipe end to form a pipe end/flange ring assembly, at least a portion of inner wall sized to be received in the recess and limit upward motion of the flange ring in the assembled pipe joint, inserting pipe end/flange ring assembly into a socket to form an assembled pipe joint, the assembled pipe joint further comprising a gap between the pipe end and socket over a portion of the assembly inserted into the socket and an injection port, and injecting a curable adhesive to fill the gap and exit through the slit in the flange ring.
[0011] The method may also include the step of fitting the flange ring onto the pipe end, the flange ring is pulled open at the slit to slide the portion thereof that is received into the recess over the bottom of the pipe end into the recess in the outer wall of the pipe end.
[0012] Further aspects and embodiments are described in the Drawings, Detailed Description and/or Claims that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a side plan view of an assembly of a first pipe end with a flange ring of one inventive embodiment mounted thereon and of a socket before insertion of the first pipe end/flange ring assembly therein.
[0014] FIG. 2 is a top perspective view of the flange ring shown in FIG. 1 .
[0015] FIG. 3 is a bottom perspective view of the flange ring shown in FIG. 1 .
[0016] FIG. 4 is a cross-sectional view of the pipe, flange ring and socket of FIG. 1 with the pipe and flange ring partially inserted into the socket.
[0017] FIG. 5 is a cross-sectional view of the assembled pipe joint assembly of FIG. 1 .
[0018] FIG. 6 is a side plan view of an assembly of a first pipe end with an alternate embodiment of an inventive flange ring mounted thereon, and of a socket before insertion of the first pipe end/flange ring assembly therein.
[0019] FIG. 7 is a top perspective view of the flange ring shown in FIG. 6 .
[0020] FIG. 8 is a bottom perspective view of the flange ring shown in FIG. 6 .
[0021] FIG. 9 is a cross-sectional view of the assembled pipe joint assembly of FIG. 6 .
[0022] FIG. 10 is a side plan view of an assembled joint of in FIG. 9 , but with the socket formed of transparent plastic and showing the adhesive partially filling the gap.
[0023] FIG. 11 is a view as in FIG. 10 at the completion of adhesive injection.
DETAILED DESCRIPTION OF THE INVENTION
[0024] All published documents, including all US patent documents, mentioned anywhere in this application are hereby expressly incorporated herein by reference in their entirety. Any copending patent applications, mentioned anywhere in this application are also hereby expressly incorporated herein by reference in their entirety.
[0025] The terms socket and pipe end are used herein to apply to pipe fitting joints in which a tubular end is fitted telescoping into a tube of larger diameter. The tubular portions may be formed integrally at the ends of pipes or be separate pipe fittings or a combination of a pipe fitting and a pipe end. The socket is the portion of the outer tube that is used in the assembled joint and the pipe end is the portion of the inner tube that is used in the joint. The joints may be linear, bent or branched, for instance a pipe having an enlarged end that joins to a straight pipe end, a sleeve fitting coupling two pipe ends, two pipes of different diameters fitted telescopingly, pipe fittings to heating tanks or boilers, and various multi-pipe fittings such as tee, Y and 4-way fittings coupling three or more pipe ends, manifold joints and the like.
[0026] As used herein the terms “top” and “bottom” and “up” and “down” are used arbitrarily to describe opposite axial directions in the pipe joint, and parts are named in relationship to that arbitrary choice. It will be understood that in practice the joint may be oriented in any direction. These descriptions do not imply the actual orientation of the joint relative to any external coordinates, in particular they are not relative to ground.
[0027] In accordance with some embodiments of the invention injection joints are simplified with a flange ring that is redesigned to include the injection port. The insertion portion of the flange ring is modified to include an inner channel that communicates with the injection port and directs the adhesive into the socket/pipe gap. Similarly, the flange ring can be configured to provide an outlet port for expelling air from the gap when adhesive is injected into the joint. These features minimize or eliminate the modifications needed to adapt a socket for use in an injection joint.
[0028] Use of a slit flange ring also allows the flange ring to be fitted on the pipe end by opening the ring so that the annular engagement of the ring occurs on a portion of the pipe end that has a recess in the outer surface. A suitably sized recess on the pipe end, in turn, provides an enhanced injection gap while maintaining desired alignment over the length of the joint. The pipe end recess also includes an edge which provides an axial engagement to the top of the flange ring, eliminating a need for clamping the flange ring during injection.
[0029] Various of these features can be implemented separately, in combination and/or in sub-combination. In a particularly preferred embodiment they are all implemented in a single embodiment as illustrated in the Figures.
[0030] One embodiment of a flange ring of the invention is depicted in FIGS. 1-5 . The flange ring 10 includes an injection port 11 . A slit 13 is provided at a location spaced circumferentially from the injection port. In this embodiment the injection port is located diametrically opposite the injection port 11 , as shown in FIGS. 2 and 3 . The ring has a top side 12 , a flange flat surface 14 , a socket insertion portion 16 , an inner ring wall 18 which provides and engagement surface with the pipe end, and an outer ring wall 20 that extends between the flange flat surface 14 and the top of the ring. A channel communicating with port 11 is provided by a recess 22 in the inner ring wall 18 . In this embodiment the recess 22 is annular.
[0031] The slit 13 has two functions. It allows the flange ring to be opened sufficiently to be slipped over the bottom 31 of the pipe end during assembly, and it functions as the exit port for the adhesive. In this embodiment the insertion portion 16 is tapered on both the inner side 17 and outer side 19 , so that the insertion portion becomes increasingly flexible moving down from the flange flat surface 14 .
[0032] In assembly of the joint a first pipe 30 and a socket 50 are provided. Preferably an industrial standard plastic socket fitting and an industrial standard pipe are used. The pipe is cut with a square end. The first pipe has a diameter that is slightly smaller than the inner diameter of the socket so that the two can be fitted with a gap. The pipe end 31 is square cut (i.e. perpendicular to its axis), suitably with a wheel cutter that leaves a small raised edge 32 . The raised edge can be left in place and force fit into the socket to provide a very short region of interference between the pipe end and the socket as shown at 38 in FIG. 5 . The pipe fitter can force fit the raised edge into the socket, typically without mechanical assistance, although for some fittings it may be useful to utilize a tool that axially forces the pipe into the socket (or vice versa). The interference fit at 38 provides sufficient sealing of the bottom of the gap to allow injection of the adhesive without significant leakage at the socket bottom.
[0033] A short distance from the pipe end 31 , a recess 34 in the outer wall is provided. A stub 35 is left at the end that retains the original pipe diameter. The recess 34 may be provided by routing or grinding at the site of installation. The length of stub 35 is not particularly critical, so long as a sufficient length of original pipe diameter is provided to assure axial alignment of the pipe in the socket and to support the interference fit of the edge 32 . This will depend on the diameter of the pipes being joined and the length of the socket, but typically may be in the range of about 0.2-1 inches (5-25 mm), for instance about 0.25″-0.5.″ (6-13 mm), or 0.25-0.375 inches (6-10 mm), for pipes having diameters in the range of 1-12 inches (25-305 mm). In some embodiments the stub length is in the range of 5-33% of the length of the pipe end that is inserted into the socket. In some embodiments a router is may be mounted a wheeled cutter so that the pipe is cut and the recess 34 is routed in the same operation. This has the advantage that the spacing of the recess is fixed reliably with each pipe cut. The recess 34 provides an enlargement of the manufactured gap between the socket and pipe so that the adhesive flow during injection can be controlled at relatively low injection pressure, e.g., the pressure provided with mechanical caulking guns and similar devices.
[0034] The depth of the recess 34 is not particularly critical, but should not be sufficient to materially reduce the burst rating of the first pipe and still provide some increase in adhesive flow rate. Depths of 0.01-0.05 inches (0.25-1.25 mm) for instance 0.015-0.03 inches (0.38-0.76 mm) may be suitable. In an alternative, not shown, the diameter of the first pipe may interfere with the socket and the length of stub 35 may be sized to allow it to be force fit into the socket. In such case the recess 34 might need to be somewhat deeper.
[0035] The diameter of the inner ring wall 18 of the flange ring is substantially the same as that of the outer diameter of the first pipe in the recess 34 . This provides frictional engagement of the flange ring with the pipe end in the recess 34 .
[0036] To assemble a pipe joint the flange ring is pulled open at the slit 13 sufficiently to be fitted over the pipe end and into the recess 34 as shown in FIG. 1 . The flange ring is then slid up the recess until the top 12 contacts the upper recess edge 33 of the first pipe. The upper recess edge 33 functions as a stop, preventing further upper displacement of the flange ring as the first pipe end is inserted into the socket and when the adhesive is injected.
[0037] The socket 40 , may be a bell on the end of a second pipe or may be any pipe fitting with a cavity sized to closely receive a pipe of the diameter of the first pipe. The socket has a top end 42 , and a substantially cylindrical inner wall 44 which has an inner diameter. In some embodiments a bevel 48 between the socket end and the inner wall 44 is provided to facilitate insertion and alignment of the axes of the first pipe and the socket.
[0038] In some embodiments the socket includes an inner bottom 49 of reduced diameter which limits the distance in which a pipe end may be inserted, but this is not a necessary feature of a socket and pipe end joint or of the inventive joints. In the embodiment shown in FIGS. 1-5 , the location of edge 33 of the pipe end and the length of the outer wall 20 of the flange ring will set the limit that the pipe end may be inserted and the upper edge 33 should be set at a location which allows insertion of the pipe end only for a distance that is less than or equal to the distance from the top 41 of the socket to the bottom 49 .
[0039] Referring to FIG. 4 , the insertion portion of flange ring is sized so that the bottom of the insertion portion 16 contacts the bevel 48 as the first pipe is inserted into the socket. The thin flexible end of the insertion portion will be deflected inward by the bevel 48 as the first pipe inserted further into the socket.
[0040] Referring to FIG. 5 , a fully assembled joint is shown before adhesive injection. The flange flat surface 14 contacts the top 49 of the socket, the top of the flange ring contacts the upper edge of the recess, the insertion portion of the flange ring has been deflected inward, but the tapering of the inner wall results in a channel 50 that is largely the same size as the gap 52 between the socket and pipe recess.
[0041] Injection of adhesive through port 11 will fill gap 44 circumferentially. The viscosity of the adhesive is suitably low enough to assure that there are no voids formed. As the adhesive is injected, pressure against the thin insertion portion of the ring maintains a seal along the bevel 48 , frictional engagement between the inner wall 18 of the ring and the recess 34 maintains a seal at the interface 55 , and the interference fit at the bottom of the pipe end seals the bottom of the gap. Air being expelled through the slit 13 prevents the adhesive from filling the slit until the adhesive has filled the gap. The slit is monitored and the adhesive injection is stopped went the adhesive appears at the slit, or just slightly exudes from the gap.
[0042] The engagement of the top side 12 of the flange ring with the edge 33 of the pipe recess 34 blocks axial displacement of the flange ring when the assembled joint is injected with adhesive. In embodiments of the invention employing this feature it is not necessary to hold or clamp the ring during injection.
[0043] The difference between the inner diameter of the socket and the outer diameter of the pipe may correspond to the manufacturing specifications for conventional solvent adhesive joints. The difference defines a narrow gap which is inherent in the assembly. The depth of the recess 34 is sufficient to provide an enlarged gap 52 that is large enough to facilitate the desired circumferential flow of the adhesive to be injected.
[0044] Another embodiment of an inventive flange ring is shown in FIGS. 6-11 . The flange ring 110 includes an injection port 111 . A slit 113 is provided at a location spaced circumferentially from the injection port, suitably diametrically opposite the injection port as shown in FIGS. 7 and 8 . The ring has a top side 112 , a flange flat surface 114 , a socket insertion portion 116 , and an inner engagement surface which is the inner ring wall 118 and an outer ring wall 120 that extends between the flat surface 114 and top of the ring. A channel communicating with port 111 is provided by a slot 122 in the inner ring wall. The channel communicates with the gap into which the adhesive will be injected. In this embodiment the slit 113 also has two functions. It allows the flange ring to be opened sufficiently to be slipped over the end portion 31 of the pipe end during assembly, and it functions as the exit port for the adhesive. In this embodiment the insertion portion 116 is straight on both the inner and outer sides.
[0045] The first pipe end is prepared in the same way as the previous embodiment and the same numerals are shown for the features of thereof. The inner wall of the flange ring is substantially the same as the outer diameter of the pipe end in recess 34 so that it frictionally engages the recess when mounted thereon.
[0046] The socket 140 has a top end 142 , and a substantially cylindrical inner wall 144 which has an inner diameter. In this embodiment the socket wall has a reduced wall thickness at end portion 145 at the top end of the socket. The reduced wall thickness is provided by a enlargement of the inner diameter of the socket. This may be a feature of the socket as manufactured or it may be a modification made at the time of installation, e.g. by routing or grinding an annular ring in the inner wall of a manufactured socket. The thinner wall at end portion 145 provides room to accommodate the insertion portion of the flange ring 110 , and may also provide a somewhat greater wall flexibility relative to the remaining portion of the socket wall.
[0047] The thickness of the insertion portion 116 of the flange ring 110 is preferably set to provide a very slight interference with the socket at end portion 145 , but preferably not more than can be accommodated by hand forcing of portion 116 into the socket end portion 145 . For instance in socket for a 10 ″ diameter polyolefin pipe an interference of 0.001-0.005 inches may be suitable.
[0048] Referring to FIG. 9 , a fully assembled joint of the second embodiment is shown before adhesive injection. The flange flat surface 114 contacts the top 149 of the socket, the top of the flange ring contacts the upper edge of the recess, the insertion portion of the flange ring is sealed on both inner and outer sides due to the radial pressure provided by the slight interference with socket end portion 145 .
[0049] The engagement of the top side 112 of the flange ring with the edge 33 of the pipe recess 34 blocks axial displacement of the flange ring when the assembled joint is injected with adhesive.
[0050] FIG. 10 is a side view of a joint as in FIG. 8 in which the socket 140 has been formed of transparent plastic. Adhesive material 160 is being injected. The gap is filled circumferentially first at the bottom of the joint because air being expelled though the slit keeps the gap open at the top.
[0051] FIG. 11 is a view as in FIG. 9 , with the adhesive just emerging from the slit. The pipe fitter can watch for the appearance of the adhesive and stop injection pressure at this point. In at least some embodiments a button 162 of adhesive is allowed to slightly overlap the outer wall 122 of the flange ring so that the edge of the slit 113 are held mechanically, as well as adhesively, when the adhesive cures.
[0052] Other variations not shown may be made. In variations of either the first or the second embodiment, the ring is formed of a material of sufficient elasticity that it can be formed without the slit and the inner diameter of the ring is temporarily deformed as it is pulled over the pipe end and into the gap 34 . Various rubbery materials may be suitable for such embodiments, for instance silicones, thermoplastic elastomers and the like. In such cases an exit port may be provided with the same configuration as the entry port. In other variations one of the entry port or the slit may be omitted and replaced with a port at the top of the socket.
[0053] In still other embodiments, not shown the pipe end recess 34 may not extend into the flange ring and instead the flange ring inner wall is sized to frictionally engage the manufactured diameter of the pipe. In such cases the flange ring advantageously provides at least one or both of the entry and exit ports, but the assembly may have to be clamped during adhesive injection.
[0054] In other embodiments the socket may be modified to include an annular recess as shown U.S. Pat. No. 7,341,285, McPherson.
[0055] It should be understood that the invention has been described for the typical cylindrical pipe shape. The pipe may of course have a non-circular cross-section, in which case the respective socket and ring cross-sections should be complementary.
[0056] The adhesive is any adhesive suited for injection bonding the pipe materials. In preferred examples the adhesive is curable for instance based on polymerization or crosslinking of epoxy, acrylic, styrene and/or unsaturated polyester monomers or oligomers. The adhesive is suitably a substantially 100% solids adhesive that cures to a solid plastic. Two-part curable adhesives may be used such as epoxy adhesives, two-part urethanes and two-part acrylic adhesive that cure when the two parts are mixed. In specific examples the adhesive is a two-part curable acrylic adhesive such as described in Briggs US 20070155879; US 20070155899; U.S. Pat. No. 7,816,453; U.S. Pat. No. 7,795,351; U.S. Pat. No. 6,852,801; U.S. Pat. No. 6,602,958; U.S. Pat. No. 5,945,461; U.S. Pat. No. 5,206,288; ; U.S. Pat. No. 5,112,691; U.S. Pat. No. 4,959,405; U.S. Pat. No. 4,942,201; U.S. Pat. No. 4,773,957; U.S. Pat. No. 4,714,730; U.S. Pat. No. 4,536,546; U.S. Pat. No. 4,426,243; U.S. Pat. No. 4,183,644; U.S. Pat. No. 4,112,013; U.S. Pat. No. 4,106,971; U.S. Pat. No. 3,890,407; U.S. Pat. No. 4,200,400; U.S. Pat. No. 5,539,070; WO 98/32206; WO 01/44311; or U.S. Pat. No. 7,341,285. The adhesive may also be a one part adhesive such as a moisture curable urethane, a hot melt, an anaerobic curing acrylic or a cyanoacrylate adhesive.
[0057] Fillers and polymers may be utilized in the formulation to reduce shrinkage during cure, to provide suitable viscosity and thixotropy, and to provide desired cured properties such as high temperature stability, low temperature flexibility, cohesive strength and the like.
[0058] The injection ring is not limited for use with curable adhesives only. Solvent cements can also be used with the injection ring to fill the interstitial space.
[0059] The flange rings of the invention can be more effectively integrated into the bonded assembly than those of the prior art because they have larger adhesive contact areas and the adhesive forms a key way when cured that more effectively integrates the ring in the bonded assembly.
[0060] The pipe end and socket may be the same or different materials. In specific examples the pipe is a homopolymer or copolymer of one or more ethylenically unsaturated monomers, for instance olefin monomers, such as ethylene, propylene and butylene, vinyl monomers including vinyl chloride; of other ethylenically unsaturated monomers including acrylonitrile, acrylates, styrene, vinyl monomers, vinylidine fluoride, and the like. Particular examples include polyolefins such as polyethylene (PE), crosslinked polyethylene (PEX), polypropylene (PP), polybutylene; polyacetal; ABS, polyvinylchloride, chlorinated polyvinylchloride, polytetrafluoroethylene and the like. Composite pipe may be used for instance fiber reinforced thermoset polymers such as cured epoxy, acrylic, styrene and/or unsaturated polyester resins. Suitable reinforcing materials include carbon fibers, carbon nanotubes, glass fiber, mineral fibers, polymer fibers, such as polyaramid (Kevlar®) or polyolefin such as Spectra®, and the like.
[0061] The flange ring may be made of the same or different materials as the pipe and/or socket. The flange ring is suitably made of a plastic material, relatively rigid or resilient materials can be used. Various thermoplastic or crosslinked plastic materials can be used, provided the adhesive is one that provides good adhesion to each component of the joint.
[0062] In further aspects the invention also pertains to a pipe end design for an injection joint that includes an engagement portion which engages a top surface of a flange ring to prevent axial displacement of the ring during injection.
[0063] The above examples and disclosure are intended to be illustrative and not exhaustive. These examples and description will suggest many variations and alternatives to one of ordinary skill in this art. All these alternatives and variations are intended to be included within the scope of the claims, where the term “comprising” means “including, but not limited to”. | An injection joint for a socket and pipe end pipe joint, which includes a socket, a pipe end inserted into the socket with a gap therebetween, and an flange ring capping the socket. Flange rings are disclosed which include an injection port and/or a slit. Injection joints may provide a recess in the pipe OD into which the flange ring is received, the recess functioning to stop travel of the flange ring during injection and widening the gap to facilitate adhesive travel. The split in the ring facilitates mounting the ring into the recess and functions as exit port. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to the field of primers and adhesion promoters. More specifically, the primer of the present invention is comprised of one or more multi-carbonylated methacrylates. In a preferred embodiment, a non-ketone polar solvent is also employed.
[0002] The disclosed primer has particular utility as a primer for nails and other proteinaceous substrates. For a number of years, nail technicians have searched for acceptable substitutes for extremely corrosive primers that cause yellowing of nail enhancements. These (meth)acrylic acid-based primers (and all other current nail primers) rely on relatively weak hydrogen bonding to achieve interfacial bonding. In contrast, the present invention is a significant advance in the art—a non-corrosive, non-yellowing primer that covalently bonds to the nail plate. In other words, the disclosed primer will not corrode or irritate the surrounding tissue or nail plate, nor will it discolor the artificial nail enhancement, while simultaneously bonding the enhancement to the keratin substrate far more strongly than currently available products.
BACKGROUND OF THE INVENTION
[0003] The nail plate (i.e., the natural nail) is primarily composed of keratin, a water-insoluble, fibrous protein that is a major structural component of skin, hair, wool, silk, feathers, scales, nails and hooves. While keratins can obviously differ greatly in their amino acid makeup, hard keratins may all be generally characterized as cross-linked polypeptides. Alpha-keratins such as nails and hooves may be further characterized by their relatively higher percentages of the amino acid cysteine. Typically, the alpha-helix coils of the polypeptides are cross-linked with disulphide bonds between adjacent cysteines. The resulting plate-like cells are cemented to each other with a sticky substance and held together by rivet-like structures called desmosomes. Many cell layers adhere to each other to form the nail plate—a structure that resembles a brick and mortar wall.
[0004] Primers are adhesion promoters that improve adhesion by increasing interfacial compatibility between surfaces, e.g., the nail plate and an applied coating. For example, a coating of nail polish will resist chipping and peeling if a good base coat is used. Base coats are more compatible with the nail plate than the nail polish. Base coats act as the “go-between” or “anchor”, to improve adhesion.
[0005] Primers are also frequently used with artificial nail enhancements since acrylic nail products normally have poor adhesion to nail plates. In general, nail plate primers can be thought of as double-sided sticky tape, joining the nail plate to the nail enhancement. The nail plate surface is made up of chemical groups possessing specific structures. Primer molecules must match the chemical and structural characteristics of the nail plate. More particularly, one end of the primer is reactive with the methacrylate monomers. With these types of primers, physical abrasion of the nail plate is required to achieve proper levels of adhesion to the keratin substrate. Moreover, these acids are corrosive, and if used improperly they can cause damage to the nail plate and surrounding tissue. These acids can also cause discoloration of the nail enhancement and are a leading cause of nail product discoloration. This invention eliminates a large percentage of discoloration problems for professional nail technicians. But even more importantly, in response to a number of chemical burn injuries, primarily to children, the Consumer Product Safety Commission recently issued a regulation requiring child-resistant packaging for all household products containing more than 5% methacrylic acid. However, child-resistant caps increase the risk of spills in the salon as Nail Professionals struggle to remove the cap. This invention solves both the burn injury and child-resistant cap issues because it utilizes a non-corrosive solvent, while still providing the desired adhesion properties.
[0006] Commercially available nail primers rely solely on hydrogen bonding. Hydrogen bonding on organic substrates such as keratin typically depends on the interaction between an oxygen or nitrogen atom that is covalently bonded to the upper surface of the nail plate and a hydrogen atom, covalently bonded to methacrylic acid, which is covalently linked to the polymer. A special type of interaction called a hydrogen bond exists between the interfaces of these dissimilar surfaces. Hydrogen bonds are types of attractive, intermolecular bonds that are characteristic of atoms with high electonegativity, i.e. fluorine, oxygen, sulfur, and nitrogen. They are many times weaker than the weakest covalent bond, which is found between a carbon and acidic hydrogens such as C—H as found in chloroform and acetylene. This weakness accounts for the attraction between the acidic hydrogen and a nearby organic, acidic hydroxyl group of acrylic or methacrylic acid primer, as well as the inherent relative weakness of hydrogen bonds. The overall strength of the hydrogen bond is determined by the strength of this relatively weak carbon/hydrogen bond. It is a controlling factor in hydrogen bond strength. Therefore, when acidic primers are used, the weakest adhesive link will exist between an oxygen molecule on the keratin surface and the acidic hydrogen of (meth)acrylic acid. Since covalent bonds are many times stronger than hydrogen bonding, improvements in adhesive bond strength can be achieved by eliminating the hydrogen bond and replacing it with a stronger, more permanent, organic covalent bond.
[0007] It is clear from the foregoing that there are three fundamental problems with currently available methacrylic primers and acrylic acid adhesion promoters. First is the corrosive nature of their primary component, methacrylic acid. Second, they create temporary hydrogen bonds that are inherently weaker than covalent bonds, leading to a weaker interfacial adhesive bond between the natural nail plate and the primer molecule, with a stronger adhesive bond between the primer molecule and the polymer chain of the nail enhancement. Third, acid-based primers are a primary cause of nail enhancement discoloration. Fourth, acid-based primers can result in chemical burn injuries.
SUMMARY OF THE INVENTION
[0008] The present invention solves the discoloration and corrosiveness problems associated with currently available primers by providing the first truly non-corrosive, non-yellowing covalently bonding primer. To date, nail primers and adhesion promoters have been corrosive due to their use of methacrylic or acrylic acid as the primary component. The present invention does not rely on these problematic components. Previous nail primers relied on relatively weak hydrogen bonding between nail and primer. The present invention employs components that are capable of creating continuous covalent bonds from the nail plate to the artificial nail enhancement, providing much improved adhesion. Additionally, previous nail primers were a prevalent cause of yellowing during “fills” when the primer came into direct contact with existing nail enhancement product on the natural nail. When using traditional primers, Nail Professionals must take great care to avoid the acid-based primer coming into contact with the artificial nail. Every two weeks when the artificial nail is “filled in” in the areas of new growth, dark yellow bands appear across the width of the nail enhancement when the (meth)acrylic acid primer comes into contact with the existing enhancement polymer.
[0009] These and other advantages are accomplished by the present invention, which relates to a primer comprised of one or more multi-carbonylated methacrylates. In a preferred embodiment, acetoacetoxy ethyl methacrylate (“AAEMA”) is reacted with polyoxypropylenetriamine to produce an imine, or Schiff base, in an equilibrium reaction. In alternative embodiments, triethyleneglycoldiamine or other primary amines can be used instead of triethyleneglycoldiamine to achieve similar results. Simultaneous with this imine reaction, an amine group of the polyoxypropylenetriamine may also react with a carbonyl ester group of AAEMA to form an amide. Finally, the Schiff base undergoes a further electron rearrangement reaction in which an electron shifts to the beta carbon of the acetoacetoxy group (as shown below).
[0010] The resulting composition does not exhibit undesirable corrosive properties and is not based on (meth)acrylic acid and, in fact, contains no acidic functionality. Moreover, the disclosed primer provides stronger adhesion than any commercially available nail primer because it allows certain amino acid functional groups on the surface of the nail plate to covalently bond with carbonyl groups in the primer, creating much stronger linkages than can be achieved with hydrogen bonding of traditional primers.
[0011] Other objects, features, and characteristics of the present invention, as well as the methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description, which forms part of this specification.
DETAILED DESCRIPTION OF THE INVENTION
[0012] As required, a detailed illustrative embodiment of the present invention is disclosed herein. However, techniques, systems, and operating structures in accordance with the present invention may be embodied in a wide variety of forms and modes, some of which may be quite different from those in the disclosed embodiment. Consequently, the specific structural and functional details disclosed herein are merely representative, yet in that regard, they are deemed to afford the best embodiment for purposes of disclosure and to provide a basis for the claims herein, which define the scope of the present invention. The following presents a detailed description of a preferred embodiment (as well as some alternative embodiments) of the present invention.
[0013] The present invention is a dramatically improved primer that is particularly appropriate for use with nails. Herein, “nail” refers to not only human nails, but also nails and hooves of animals, and any other hard surface proteinaceous materials. The nail primer of the present invention is principally comprised of multi-carbonylated methacrylates dissolved in a suitable solvent or other delivery system. In a preferred embodiment of the present invention, the aforementioned components may be diluted in polar non-ketone solvents, however, non-polar solvents will work as well.
[0014] Various formulas have been tested by the applicant. One preferred embodiment comprises a polyether amine having a hydrophilic backbone, an acetoacetoxy methacrylate, and a polar non-ketone solvent. Of course, other components can be substituted as described below. One preferred polyether amine is triethyleneglycoldiamine. Again, other similar components (such as polyoxypropylenetriamine) can be utilized to achieve the results of this invention.
[0015] The preferred amines contain two or three primary amine functional groups, respectively. The primary amine functional groups are located on secondary carbon atoms at the ends of aliphatic polyether chains. Other primary amines, including monofunctional, difunctional and trifunctional amines, may be used in the present invention to achieve the desired results. Such primary amines include all polyetheramines, including but not limited to polyethyleneglycolamine, polyoxypropyleneamine, polyethyleneglycol-polyoxypropyleneamine, polyoxypropylenediamine, polyethyleneglycol-polyoxypropylenediamine, polyethyleneglycoltriamine, polyethyleneglycol-polyoxypropylenetriamine. Some examples of the above-mentioned components include, but are not limited to melamine, N,N-dimethylformamide, 1,5-diaminopentane and dibutylamine.
[0016] One particularly preferred multi-carbonylated methacrylate is acetoacetoxy ethyl methacrylate (referred to herein as “AAEMA”).
[0017] The preferred solvent of the present invention is a non-ketone solvent. This ensures that the solvent will not react with the carbonyl group in the methacrylate, nor compete with the AAEMA carbonyl reaction. In nail applications, this helps prevent yellowing of the nail enhancement. However, in alternative embodiments of the invention where perhaps a slight coloration to the solvent blend would not be objectionable, a ketone solvent can be utilized if appropriate conditions are used during the bulk chemical reaction.
[0018] The solvent utilized in the present invention is also preferably a polar solvent to minimize the amount of discoloration which is observed when a non-polar solvent is utilized. However, in alternative embodiments of the present invention, a non-polar solvent can be utilized without compromising the integrity of the primer, which retains its adhesive and non-corrosive properties. Particularly preferred polar non-ketone solvents include ethanol and isopropanol. Other useful solvents include, but are not limited to, ethers, esters, glycol ethers, chlorinated solvents, siloxanes, tetrahydrofuran, methanol and other higher molecular weight alcohols, and suitable combinations thereof.
[0019] The weight percentages of the epoxy amine component in the tested formulas ranged from 0.75 to 2.5 percent, while the molar ratios of AAEMA to amine ranged from 1 to 5. Upon mixing, the carbonyl group of the acetoacetoxy group of AAEMA reacts with the primary amine group to form an imine, or Schiff base. In a preferred embodiment, the primary amine is triethyleneglycoldiamine. This reaction proceeds as follows:
[0020] wherein R represents the remainder of the amine. Other amine groups may also react with AAEMA. This reaction is followed by electron re-arrangement favoring the beta carbon of the acetoacetoxy group:
[0021] It should also be appreciated that the amine groups can also react with AAEMA ester groups to form an amide:
[0022] Analytical testing using a Liquid Chromatography Mass Spectrometer (LC-MS) demonstrates that the imine formation reaction takes place more readily than the amide formation reaction. Further analytical testing using a Gas Chromatograph Mass Spectrometer (GC-MS) indicates that less than 10 percent of the AAEMA reacted in the amide formation reaction. Additional testing confirms that increasing the molar ratio of AAEMA to amine increases the number of amine functional groups that react with AAEMA.
[0023] While the preferred embodiment of the present invention has been illustrated with the reaction of an AAEMA and a polyether amine (such as polyoxypropylenetriamine), other multi-carbonyl methacrylate chemicals, and other amines may also be used. By using chemicals with slightly different properties, the resulting primer can effectively adhere to a wide variety of surfaces, such as glass, metal, sheetrock, etc., to act as a primer for other applications.
[0024] Comparative testing on the adhesion promoting activity of the improved primer of the present invention was performed both in a laboratory (with an instrument that tests adhesion) and in the field by professional nail technicians. Laboratory testing showed that the primer functioned better than its ingredients (amine, AAEMA, and ethanol) individually. More importantly, the nail primer of this invention worked better than all other commercially available nail primers tested.
[0025] The following procedure was used in the laboratory testing. First, a clean keratin substrate (hoof) was coated with the tested primer. A system utilizing ethyl methacrylate monomer liquid and a methacrylate copolymer powder was applied to the top of the primed hoofs. After the monomer and copolymer completely polymerized, adhesion testing apparatus utilizing a computer controlled assembly, including a sharp blade held at a precise angle to the surface of the hoof, was used to peel or delaminate the methacrylate polymer from the coated keratin substrate at a predetermined speed. The force needed to delaminate the polymer was detected and recorded by the computerized control system. The greater the force needed to peel or delaminate the polymer from the keratin substrate, the stronger the adhesive bond was to the keratin substrate. Table 1 illustrates the results of the laboratory tests:
TABLE 1 Adhesion Standard Strength Deviation N N Main Ingredients Company Advanced 300 65 Methacrylic acid, Pinnacle Formula Isobutyl Methacry- Primer late X- 340 60 Methacrylic acid, Star Nail Strength Isobutyl Methacry- Primer late Original 400 65 Methacrylic acid, International Non- Isobutyl Methacry- Nail Lifting late Manufacturers No Lift 490 105 100% Methacrylic No Lift Nails Primer acid Bondex 500 80 Methacryloyloxy- O.P.I ethyl maleate, ethyl acetate Coval- 570 140 Polyoxypropylene- Creative Nail ently triamine, AAEMA, Design Bonding Ethanol Primer
[0026] The improved nail primer of the present invention shows average adhesion strength of 570 N. The strongest commercially available primer had adhesion strength of only 500 N.
[0027] The significant increase in strength achieved by the disclosed primer can be largely attributed to its ability to covalently bond to the nail plate. As was previously discussed, presently available primers, including those identified in Table 1 (other than the present invention) are bonded to the nail plate via hydrogen bonding. In contrast, applicant's primer takes advantage of the greatly increased bond strengths attained through covalent bonding.
[0028] Obviously, with individual differences in both keratins and nail surfaces, a number of covalent reaction mechanisms are possible. It is anticipated, however, that two reactions will dominate. Because of the surprisingly high level of adhesion, we believe our data shows that the dominant reaction involves a direct, continuous series of covalent bonds between the keratin and the enhancement polymer. In the first, ester groups in the primer react with amines in keratin:
[0029] where R is the rest of the primer. In the alternative reaction, amines in the primer react with carboxylic groups in keratin:
[0030] where R′ is the rest of the primer.
[0031] In any given case, one reaction might dominate over the other, or both reactions may proceed simultaneously. Those of skill in the art will appreciate that it is not the precise reaction mechanism that is important, but rather the fact that covalent bonding, via one or more mechanisms, is occurring. This is the advance that arguably will make all previous nail primers obsolete.
[0032] Confirmatory data was also collected in field tests. In a two month study, 18 nail technicians performed tests on a total of 429 clients. The tests showed that the client's nail enhancements were less likely to lift when using the primer of the present invention. Moreover, while discoloration of nail enhancements is inevitable when using a primer that contains methacrylic acid, use of the primer of the present invention eliminated such discoloration. To date, the improved primer of the present invention has been field tested on 4,582 people yielding equally successful results.
[0033] While the present invention has been described with reference to one or more preferred embodiments, which embodiments have been set forth in considerable detail for the purposes of making a complete disclosure of the invention, such embodiments are merely exemplary and are not intended to be limiting or represent an exhaustive enumeration of all aspects of the invention. The scope of the invention, therefore, shall be defined solely by the following claims. Further, it will be apparent to those of skill in the art that numerous changes may be made in such details without departing from the spirit and the principles of the invention. | The present invention relates generally to the field of primers and adhesion promoters. More specifically, the primer of the present invention is comprised of one or more multi-carbonylated methacrylates. In a preferred embodiment, a non-ketone polar solvent is also employed. The resulting composition eliminates primer related discoloration of artificial nail enhancements, eliminates the potential for corrosion of skin and nails, and eliminates risk of chemical burn injury, while providing stronger adhesion than currently available primers. | 2 |
This is a divisional of U.S. patent application Ser. No. 11/389,318 filed Mar. 24, 2006, now U.S. Pat. No. 7,665,967, which is a Continuation-In-Part of Design application Ser. No. 29/252,288 filed Jan. 20, 2006 no U.S. Pat. No. D594,551.
FIELD OF INVENTION
This invention relates to ceiling fans, and in particular to efficient traditionally appearing ceiling fan blades with aerodynamical upper surfaces and wide tip ends for ceiling fans with blades formed from plastic and/or wood and/or be separately attached as an upper surface, that run at reduced energy consumption that move larger air volumes than traditional flat shaped ceiling fan blades, and to methods of operating the novel ceiling fans.
BACKGROUND AND PRIOR ART
Existing flat planar appearing ceiling fans are the most popular type of ceiling fans sold in the United States, and are known to have relatively poor air moving performance at different operating speeds. See for example U.S. Pat. Des. 355,027 to Young and Des. 382,636 to Yang. These patents while moving air are not concerned with maximizing optimum downward airflow.
Additionally, many of the flat ceiling fan blades have problems such as wobbling, and excessive noise that is noticeable to persons in the vicinity of the fan blades. The flat planar rectangular blade can have a slight tilt to increase air flow but are still poor in air moving performance, and continue to have the other problems mentioned above.
Aircraft, marine and automobile engine propeller type blades have been altered over the years to shapes other than flat rectangular. See for example, U.S. Pat. Nos. 1,903,823 to Lougheed; 1,942,688 to Davis; 2,283,956 to Smith; 2,345,047 to Houghton; 2,450,440 to Mills; 4,197,057 to Hayashi; 4,325,675 to Gallot et al.; 4,411,598 to Okada; 4,416,434 to Thibert; 4,730,985 to Rothman et al. 4,794,633 to Hickey; 4,844,698 to Gornstein; 5,114,313 to Vorus; and 5,253,979 to Fradenburgh et al.; Australian Patent 19,987 to Eather.
However, these patents are generally used for high speed water, aircraft, and automobile applications where the propellers are run at high revolutions per minute (rpm) generally in excess of 500 rpm. None of these propellers are designed for optimum airflow at low speeds of less than approximately 200 rpm which is the desired speeds used in overhead ceiling fan systems.
Some alternative blade shapes have been proposed for other types of fans. See for example, U.S. Pat. Nos. 1,506,937 to Miller; 2,682,925 to Wosik; 4,892,460 to Volk; 5,244,349 to Wang; Great Britain Patent 676,406 to Spencer; and PCT Application No. WO 92/07192.
Miller '937 requires that their blades have root “lips 26 ” FIG. 1 that overlap one another, and would not be practical or useable for three or more fan blade operation for a ceiling fan. Wosik '925 describes “fan blades . . . particularly adapted to fan blades on top of cooling towers such for example as are used in oil refineries and in other industries . . . ”, column 1, lines 1-5, and does not describe any use for ceiling fan applications.
The Volk '460 patent by claiming to be “aerodynamically designed” requires one curved piece to be attached at one end to a conventional planar rectangular blade. Using two pieces for each blade adds extreme costs in both the manufacturing and assembly of the ceiling itself. Furthermore, the grooved connection point in the Volk devices would appear to be susceptible to separating and causing a hazard to anyone or any property beneath the ceiling fan itself. Such an added device also has necessarily less than optimal aerodynamic properties.
Tilted type design blades have also been proposed over the years. See for example, U.S. Pat. No. D451,997 to Schwartz.
However, none of the prior art modifies design shaped blades to optimize twist angles to optimize energy consumption and airflow, and reduce wobble and noise problems.
The inventors and assignee of the subject invention have been at the forefront of inventing high efficiency ceiling fans by using novel twisted blade configurations. See for example, U.S. Pat. Nos. 6,884,034 and 6,659,721 and 6,039,541 to Parker et al.
However, these fans have unique and to some a futuristic appearance as compared to traditional flat planar fan blades. Although, highly efficient, some consumers may tend to prefer the traditional flat planar blades that have been widely used as compared to the high efficiency ceiling fans that use twisted blades.
Thus, the need exists for better performing traditionally appearing ceiling fan blades over the prior art.
SUMMARY OF THE INVENTION
The first objective of the subject invention is to provide efficient ceiling fan blades, devices, apparatus and methods of operating ceiling fans, that preserve the traditional appearance of conventional flat planar ceiling fan blades when viewed underneath the ceiling fans.
The second objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, where the blades have aerodynamical upper surfaces.
The third objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, which move up to approximately 20% and greater airflow over traditional planar blades.
The fourth objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, that are less prone to wobble than traditional flat planar ceiling fan blades.
The fifth objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, that reduce electrical power consumption and are more energy efficient over traditional flat planar ceiling fan blades.
The sixth objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, designed for superior airflow at up to approximately 240 revolutions and more per minute (rpm).
The seventh objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, that are at least as aesthetically appealing as traditional flat planar ceiling fan blades.
The eighth objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, capable of reduced low operational speeds for reverse operation to less than approximately 40 revolutions per minute or less.
The ninth objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, capable of reduced low operational forward speeds of less than approximately 75 revolutions per minute or less.
The tenth objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, capable of reduced medium operational forward speeds of up to approximately 120 revolutions per minute, that can use less than approximately 9 Watts at low speeds.
The eleventh objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, that can have up to approximately 64 (sixty four) inch diameter (tip-to-tip fan diameter) or greater for enhancing air moving efficiency at lower speeds than conventional fans.
The twelfth objective of the subject invention is to provide efficient traditionally appearing ceiling fan blades, devices, apparatus and methods of operating ceiling fans, that can move air over large coverage areas compared to conventional flat appearing ceiling fan blades.
A preferred embodiment can include a plurality of efficient traditionally appearing ceiling fan blades, attached a ceiling fan motor. Diameter sizes of the fans can include but not be limited to less than and up to approximately 32″, 48″, 52″, 54″, 56″, 60″, 64″, and greater. The blades can be made from wood, plastic, and the like, and can include separately attachable upper aerodynamic surfaces.
A preferred embodiment of the high efficiency traditional appearing ceiling fan can include a hub with a motor, and a plurality of blades attached to the ceiling fan motor, each blade having a flat and planar lower surfaces that visually appear to be flat and planar when viewed underneath the fan, and aerodynamic upper surfaces, wherein the aerodynamic upper surfaces of the blades move greater amounts of air compared to blades having both upper and lower flat and planar surfaces. Each of the blades can have tip ends being wider than root ends that are adjacent to the motor.
The tip ends of the blades can have a width of approximately 5 to approximately 6 inches wide, and the root ends of the blades have a width of approximately 4 to approximately 5 inches wide. More preferably, the tip ends of the blades can have a width of approximately 5& ¾ inches wide, and the root ends of the blades have a width of approximately 4& ¾ inches wide. Each of the blades can have a rounded leading edge, and a blunt tipped trailing edge.
The upper surfaces of the blades can include a downwardly curving slope from the maximum thickness point to the blunt tipped trailing edge, and a mid-thickness along a longitudinal axis of the blade being thicker than both thicknesses along the leading edge and the trailing edge of the blades. The blades can be formed from molded plastic.
The aerodynamic upper surfaces can be made as part of the blades. Alternatively, the aerodynamic upper surfaces can be preformed and separately attachable to a base ceiling fan blade, the base ceiling fan blade having both upper and lower flat and planar surfaces.
A novel method of operating efficient traditionally appearing ceiling fan blades with aerodynamical upper surfaces ceiling fan, can include the steps of providing blades having a flat and planar lower surfaces that visually appear to be flat and planar when viewed underneath, and aerodynamic upper surfaces, the blades being attached to a ceiling fan motor, rotating the blades relative to the motor, and generating a CFM (cubic feet per minute) airflow of at least five (5) percent (%) greater than traditionally appearing ceiling fan blades that have both upper and lower flat and planar surfaces.
The method can further include the step generating an airflow of at least approximately 5% or greater CFM at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s) that is greater than the traditionally appearing ceiling fan blades that have both upper and lower flat and planar surfaces.
The method can include the step of generating an airflow of at least approximately 8% or greater CFM at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s) that is greater than the traditionally appearing ceiling fan blades that have both upper and lower flat and planar surfaces.
The method can include the step of generating an airflow of at least approximately 10% or greater CFM at a high rotational speed of approximately 0.50 meters per second (m/s) to approximately 0.85 meters per second (m/s) that is greater than the traditionally appearing ceiling fan blades that have both upper and lower flat and planar surfaces.
The method can include the step of generating an airflow of at least approximately 20% or greater CFM at a high rotational speed of approximately 0.50 meters per second (m/s) to approximately 0.85 meters per second (m/s) that is greater than the traditionally appearing ceiling fan blades that have both upper and lower flat and planar surfaces.
The method can include the step of generating an airflow of at least approximately 25% or greater CFM at a high rotational speed of approximately 0.50 meters per second (m/s) to approximately 0.85 meters per second (m/s) that is greater than the traditionally appearing ceiling fan blades that have both upper and lower flat and planar surfaces.
The method can include the step of generating an airflow of at least approximately 2,250 or greater total CFM (cubic feet per minute) below the rotating blades at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s). The method can further include the step of generating an airflow of at least approximately 2,500 or greater total CFM (cubic feet per minute) below the rotating blades at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s).
The method can include the step of generating an airflow of at least approximately 2,700 or greater total CFM (cubic feet per minute) below the rotating blades at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s).
The method can include the step of generating an airflow of at least approximately 5,900 or greater total CFM (cubic feet per minute) below the rotating blades at a high rotational speed of approximately 0.50 meters per second (m/s) to approximately 0.85 meters per second (m/s).
The method can include the step of generating an airflow of at least approximately 6,000 or greater total CFM (cubic feet per minute) below the rotating blades at a high rotational speed of approximately 0.50 meters per second (m/s) to approximately 0.85 meters per second (m/s).
The method can include the step of generating an airflow of at least approximately 6,300 or greater total CFM (cubic feet per minute) below the rotating blades at a high rotational speed of approximately 0.50 meters per second (m/s) to approximately 0.85 meters per second (m/s).
The method can include the step of generating at least approximately 160 or greater total CFM (cubic feet per minute) per Watts below the rotating blades at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s).
The method can include the step of generating at least approximately 175 or greater total CFM (cubic feet per minute) per Watts below the rotating blades at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s).
The method can include the step of generating at least approximately 189 or greater total CFM (cubic feet per minute) per Watts below the rotating blades at a low rotational speed of approximately 0.15 meters per second (m/s) to approximately 0.40 meters per second (m/s).
The method can include the step of generating at least approximately 100 or greater total CFM (cubic feet per minute) per Watts below the rotating blades at a high rotational speed of approximately 0.50 meters per second (m/s) to approximately 0.85 meters per second (m/s).
Further objects and advantages of this invention will be apparent from the following detailed descriptions of the presently preferred embodiments which are illustrated schematically in the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
First Embodiment Small Diameter Blades
FIG. 1A is a top perspective view of a first embodiment efficient traditionally appearing ceiling fan blade with aerodynamical upper surfaces and wide tip end.
FIG. 1B is a bottom perspective view of the blade of FIG. 1A .
FIG. 1C is a top planar view of the blade of FIG. 1A .
FIG. 1D is a bottom planar view of the blade of FIG. 1A .
FIG. 1E is a left side view of the blade of FIG. 1A along arrow 1 E.
FIG. 1F is a right side view of the blade of FIG. 1A along arrow 1 F.
FIG. 1G is a tip end view of the blade of FIG. 1A along arrow 1 G.
FIG. 1H is a root end view of the blade of FIG. 1A along arrow 1 H.
FIG. 2 is another top perspective view of the efficient traditionally appearing ceiling fan blade with aerodynamical upper surfaces and wide tip end of FIG. 1A with labeled cross-sections A, B, C, D, E, F, G, H, I
FIG. 3 is another top view of the efficient traditionally appearing ceiling fan blade with aerodynamical upper surfaces of FIG. 1A with labeled cross-sections A-I.
FIG. 4A shows the cross-section A of FIGS. 2-3 .
FIG. 4B shows the cross-section B of FIGS. 2-3 .
FIG. 4C shows the cross-section C of FIGS. 2-3 .
FIG. 4D shows the cross-section D of FIGS. 2-3 .
FIG. 4E shows the cross-section E of FIGS. 2-3 .
FIG. 4F shows the cross-section F of FIGS. 2-3 .
FIG. 4G shows the cross-section G of FIGS. 2-3 .
FIG. 4H shows the cross-section H of FIGS. 2-3 .
FIG. 4I shows the cross-section I of FIGS. 2-3 .
Second Embodiment Large Diameter Blades
FIG. 5 is a top perspective view of a second embodiment of a large efficient traditionally appearing ceiling fan blade with aerodynamical upper surfaces and wide tip end with labeled cross-sections A, B, C, D, E, F, G, H.
FIG. 6 is a top view of the large efficient traditionally appearing ceiling fan blade with aerodynamical upper surfaces of FIG. 5 with labeled cross-sections A-H.
FIG. 7A shows the cross-section A of FIGS. 5-6 .
FIG. 7B shows the cross-section B of FIGS. 5-6 .
FIG. 7C shows the cross-section C of FIGS. 5-6 .
FIG. 7D shows the cross-section D of FIGS. 5-6 .
FIG. 7E shows the cross-section E of FIGS. 5-6 .
FIG. 7F shows the cross-section F of FIGS. 5-6 .
FIG. 7G shows the cross-section G of FIGS. 5-6 .
FIG. 7H shows the cross-section H of FIGS. 5-6 .
FIG. 8A is a perspective bottom view of a ceiling fan and efficient blades of FIGS. 1-7I
FIG. 8B is a perspective top view of the ceiling fan and efficient blades of FIG. 8A .
FIG. 8C is a side perspective view of the ceiling fan and efficient blades of FIG. 8A .
FIG. 8D is a bottom view of the ceiling fan and efficient blades of FIG. 8A .
FIG. 8E is a top view of the ceiling fan and efficient blades of FIG. 8A .
Third Embodiment Rounded Wide Tip End Blades
FIG. 9A is a top perspective view of a third embodiment efficient traditionally appearing ceiling fan blade with aerodynamical upper surfaces and rounded wide tip end.
FIG. 9B is a bottom perspective view of the blade of FIG. 9A .
FIG. 9C is a top planar view of the blade of FIG. 9A .
FIG. 9D is a bottom planar view of the blade of FIG. 9A .
FIG. 9E is a left side view of the blade of FIG. 9A along arrow 9 E.
FIG. 9F is a right side view of the blade of FIG. 9A along arrow 9 F.
FIG. 9G is a tip end view of the blade of FIG. 9A along arrow 9 G.
FIG. 9H is a root end view of the blade of FIG. 9A along arrow 9 H.
Fourth Embodiment Curved Wide Tip End Blades
FIG. 10A is a top perspective view of a fourth embodiment efficient traditionally appearing ceiling fan blade with aerodynamical upper surfaces and curved wide tip end.
FIG. 10B is a bottom perspective view of the blade of FIG. 10A .
FIG. 10C is a top planar view of the blade of FIG. 10A .
FIG. 10D is a bottom planar view of the blade of FIG. 10A .
FIG. 10E is a left side view of the blade of FIG. 10A along arrow 10 E.
FIG. 10F is a right side view of the blade of FIG. 10A along arrow 10 F.
FIG. 10G is a tip end view of the blade of FIG. 10A along arrow 10 G.
FIG. 10H is a root end view of the blade of FIG. 10A along arrow 10 H.
Fifth Embodiment Separately Attachable Aerodynamic Surface
FIG. 11 is tip end exploded view of a separate attachable aerodynamic surface that can be attached to conventional flat-planar surface ceiling fan blades.
FIG. 12 is another view of FIG. 11 with the aerodynamic surface attached to the blade.
FIG. 13 is another version of the separately attachable aerodynamic surface with blade.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
The subject invention is a Continuation-In-Part of Design application Ser. No. 29/252,288 filed Jan. 20, 2006, which is incorporated by reference.
Testing of novel ceiling fan blades were conducted in July-August 2005, and included three parameters of measurement data: airflow (meters per second (m/s), power (in watts) and speed (revolutions per minute (rpm)). Those novel ceiling fan blades far surpassed the operating performance of various traditional flat planar ceiling fans in operation.
The tested blade had a reverse taper as compared to conventional blades. The tested blade was wider at the tip than the root. The first one tested had a flat bottom, a pitch of approximately 10 to approximately 12 degrees and an air foil (aerodynamic upper surface) on top (the upper surface). It is essentially a flat ceiling fan blade with an engineered air foil. We tested these by running an evaluation of a Huntington III in our lab and then changing to the new blades with the air foil on top. The short of the attached test results is that air flow was increased by approximately 10% at high speed to over approximately 26% at low speed. Again, this innovation is potentially revolutionary relative to reaching the EnergyStar designation with standard ceiling fans which is described below in relation to Table 5.
While the novel blades look completely conventional when viewed from underneath, the novel blades perform considerably better relative to their air moving efficiency. Another test gave the novel blade a very slight twist.
The modified blade is intended to move more air than the flat paddle blade, with the same input power. The aerodynamic upper surfaces allow the blade to work efficiently at both higher and lower RPM (revolutions per minute). To work effectively at lower RPM the blades can also be set at a higher pitch. The mounting brackets on the modified set of blades can be set to either a higher or lower pitch setting.
The motor efficiency was expected to change with RPM. The modified aerodynamic blades were expected to work best in conjunction with a motor that has good efficiency at slower RPM.
To separate the effects of aerodynamics and electrical motor performance a dynamometer set up was used for the testing procedures. A dynamometer measures torque and RPM. A torque sensor can be used where the motor mounts to the ceiling. With no other torques on the motor, the torque on the mount is the same as the torque on the turning shaft. The mechanical power going from the motor to the fan is equal to the torque times the RPM times a constant factor.
In English units the torque in foot-lbs times the rotational speed in radians/second is the power in foot-lbs/second. In metric units the torque in newton-meters times the rotational speed in radians/second equals the power in watts. To convert RPM into radians/second, and rad/sec=2 PI×RPM/60.
Laboratory tests were conducted on a standard ceiling fan with flat planar blades such as a 52″ Diameter Huntington III from Hampton Bay, which is sold by Home Depot, and the 52″ Hunter Silent(S) Breeze from Hunter Fan Company and compared against the novel efficient traditionally appearing ceiling fan blades, having aerodynamical upper surfaces.
The novel efficient aerodynamic blades tested had dimensions of those described in reference to FIGS. 1A-1G below, where the blades had an overall length between root end 20 and tip end 10 of approximately 20 inches, where the root end can have a diameter of approximately 3.53 inches that widens outward along blade 1 to the tip end that can have a diameter of approximately 4.53 inches.
Measurements were taken in an environmental chamber under controlled conditions using solid state measurement methods recommended by the United States Environmental Protection Agency in their Energy Star Ceiling Fan program which used a hot wire anemometer which required a temperature controlled room and a computer for testing data.
http://www.energystar.gov/ia/partners/prod_development/revisions/downloads/ceil_fans/final.pdf
In the tables below, air flow in CFM stands for cubic feet per minute, and power is measured in Watts (W).
The tested aerodynamic novel efficient fan blades had an overall diameter of approximately 52 inches across five blades, powered by a triple capacitor Powermax 188 mm by 155 mm motor. The low speed RPM (revolutions per minute) of the HUNTINGTON III was approximately 88 RPM. The low speed of the HUNTER S BREEZE was approximately 55 RPM. The low speed of the EFFICIENT NOVEL BLADES was approximately 104 RPM.
The data yielded the following improvements in Tables 1 and 2 at Low Speed of the Huntington III and the Hunter S Breeze each running at approximately 55 to approximately 88 RPM (revolutions per minute) and the novel efficient blades having a low speed of approximately 104 RPM.
Table 1 indicates the velocity measured (m/s) underneath a ceiling mounted fan with measurement location (feet from center) for the three fans (Huntington III, Hunter S. Breeze and Novel Efficient Blades) for low speed operation of the fans. The measurements were made approximately 56″ inches above the floor, and a calibrated hot-wire anemometer was used to take the measurements.
TABLE 1
Measurement
Velocity Measured
Location
(m/s)
(feet from center)
Huntington III
Hunter S. Breeze
Novel Efficient
0
0.440
0.270
0.820
0.5
0.270
0.240
0.910
1
0.420
0.370
0.990
1.5
0.520
0.480
0.780
2
0.510
0.400
0.460
2.5
0.330
0.080
0.200
3
0.160
0.010
0.180
3.5
0.100
0.000
0.120
4
0.100
0.000
0.090
4.5
0.080
0.000
0.080
5
0.030
0.000
0.080
5.5
0.030
0.000
0.030
TABLE 2 provides the average velocity (m/s), total CFM (cubic feet per minute), total Watts (power usage), and total CFM/Watts for the three fans (Huntington III, Hunter S. Breeze and Novel Efficient Blades) for low speed operation.
TABLE 2
Hunter
Fan Type
Huntington III
S. Breeze
Novel Efficient
Average Velocity (m/s)
0.25
0.15
0.40
Total CFM
2136.6
1396.1
2711.8
Total Watts
14.3
8.9
14.3
Total CFM/Watts
149.4
156.9
189.6
As shown in Table 1 at low speed, absolute flow (CFM) (2711.8/2136.6) was increased by approximately 26.9% with efficiency (189/149.4) improved by a similar amount of approximately 26.5% when comparing the novel efficient fan blades over the Huntington III fan.
Also, at low speed, absolute flow (CFM) (2711.8/1396.1) was increased by approximately 94% with efficiency (189/156.9) improved by approximately 20.45% when comparing the novel efficient fan blades over the Hunter S. Breeze fan.
For Table 3, the high speed for the HUNTINGTON III was approximately 216 RPM, the high speed for the HUNTER S BREEZE was approximately 165 RPM. The high speed for the EFFICIENT NOVEL BLADES was approximately 248 RPM.
Table 3 has data of High Speed of the Huntington III and the Hunter S Breeze each running at approximately 165 to approximately 216 RPM (revolutions per minute) and the novel efficient blades having a low speed of approximately 248 RPM.
Table 3 indicates the velocity measured (m/s) underneath a ceiling mounted fan with measurement location (feet from center) for the three fans (Huntington III, Hunter S. Breeze and Novel Efficient Blades) for high speed operation of the fans.
TABLE 3
Measurement
Velocity Measured
Location
(m/s)
(feet from center)
Huntington III
nter-Summer Breeze
Novel Efficient
0
0.790
1.135
1.040
0.5
0.770
1.905
1.330
1
1.430
2.065
2.110
1.5
1.450
1.505
2.130
2
1.250
0.580
0.960
2.5
0.850
0.185
0.690
3
0.500
0.165
0.370
3.5
0.280
0.115
0.230
4
0.170
0.130
0.200
4.5
0.130
0.120
0.200
5
0.130
0.135
0.200
5.5
0.110
0.160
0.200
TABLE 4 provides the average velocity (m/s), total CFM (cubic feet per minute), total Watts (power usage), and total CFM/Watts for the three fans (Huntington III, Hunter S. Breeze and Novel Efficient Blades) for high speed operation.
TABLE 4
Hunter-
Novel
Fan Type
Huntington III
Summer Breeze
Efficient
Average Velocity (m/s)
0.66
0.68
0.81
Total CFM
5813.9
4493.6
6341.1
Total Watts
61.8
74.8
62.5
Total CFM/Watts
94.1
60.1
101.5
As shown in Table 4 at high speed, absolute flow (CFM) (6341.1/5813.9) was increased by approximately 9% with efficiency (101.5/94.1) improved by a similar amount of approximately 7.86% when comparing the novel efficient fan blades over the Huntington III fan.
Also, at high speed, absolute flow (CFM) (6341.1/4493.6) was increased by approximately 41.1% with efficiency (101.5/60.1) improved by approximately 68.88% when comparing the novel efficient fan blades over the Hunter S. Breeze fan
Although medium speed operation is not shown, extrapolating speeds between low and high, would show that the invention would have similar benefits over the Huntington III and Hunter S. Breeze ceiling fans.
The United States government has initiated a program entitled: Energy Star (www.energystar.gov) for helping businesses and individuals to protect the environment through superior energy efficiency by reducing energy consumption and which includes rating appliances such as ceiling fans that use less power than conventional fans and produce greater cfm output. As of Oct. 1, 2004, the Environmental Protection Agency (EPA) has been requiring specific air flow efficiency requirements for ceiling fan products to meet the Energy Star requirements which then allow those products to be labeled Energy Star rated. Table 5 below shows the current Energy Star Program requirements for residential ceiling fans with the manufacturer setting their own three basic speeds of Low, Medium and High.
TABLE 5
Air Flow Efficiency Requirements(Energy Star)
Fan Speed
Mininum Airflow
Efficiency Requirement
Low
1,250 CFM
155
CFM/Watt
Medium
3,000 CFM
100
CFM/Watt
High
5,000 CFM
75
CFM/Watt
Note, that Energy Star program does not require what the speed ranges for RPM are used for low, medium and high, but rather that the flow targets are met:
For Energy Star, residential ceiling fan airflow efficiency on a performance bases is measured as CFM of airflow per watt of power consumed by the motor and controls. This standard treats the motor, blades and controls as a system, and efficiency can be measured on each of three fan speeds (low, medium, high) using standard testing.
From Table 5, it is clear that the efficient novel blades with upper aerodynamic surfaces running at all speeds of low, medium and high meet and exceed the Energy Star Rating requirements.
Other embodiments can use as few as two, three, four, and even six efficient novel blades with upper aerodynamic surfaces. The blades can be formed from carved wood and/or injection molded plastic. The ceiling fan blades can have various diameters such as but not limited to approximately 42″, 46″, 48″, 52″, 54″, 56″, 60″ and even greater or less as needed.
First Embodiment Small Diameter Blades
The labeled components will now be described.
1 novel small diameter blade 5 dotted lines for motor mount arm connection 10 tip end 20 root end 30 LE leading edge 40 TE trailing edge 50 upper surface 60 lower surface
FIG. 1A is a top perspective view of a first embodiment efficient traditionally appearing ceiling fan blade 1 with aerodynamical upper surfaces 50 and wide tip end 10 . FIG. 1B is a bottom perspective view of the blade 1 of FIG. 1A with planar/flat appearing lower surface 60 . FIG. 1C is a top planar view of the blade 1 of FIG. 1A showing upper surface 50 . FIG. 1D is a bottom planar view of the blade 1 of FIG. 1A . FIG. 1E is a left side view of the blade 1 of FIG. 1A along arrow 1 E with leading edge 30 LE. FIG. 1F is a right side view of the blade 1 of FIG. 1A along arrow 1 F with trailing edge 40 TE FIG. 1G is a tip end 10 view of the blade 1 of FIG. 1A along arrow 1 G. FIG. 1H is a root end 20 view of the blade 1 of FIG. 1A along arrow 1 H.
Referring to FIGS. 1A-1G , the novel blade can have an overall length between root end 20 and tip end 10 of approximately 20 inches, where the root end can have a diameter of approximately 3.53 inches that widens outward along blade 1 to the tip end that can have a diameter of approximately 4.53 inches. The tip end 10 and root end 20 can have flat generally flat face ends. The undersurface 60 of blade 1 can be flat and planar so as to appear to be a traditionally appearing flat sided blade when viewed from underneath the blades when mounted to a ceiling fan.
The upper surface 50 can have an efficient aerodynamic surface with a rounded leading edge 30 LE, and a blunt tipped trailing edge 40 TE. The upper surfaces of the blade 1 can include an upwardly curving slope from the rounded leading edge 30 LE to a point of maximum thickness, the point being closer to the leading edge 30 LE than to the trailing edge 40 TE. The upper surface can also include a downwardly curving slope from the maximum thickness point to the blunt tipped trailing edge 40 TE. The thickness along this maximum thickness point can run along a longitudinal axis from the root end to the tip end, and this maximum thickness can be thicker than the thickness along either or both of the leading edge 30 LE and the trailing edge 40 TE.
FIG. 2 is another top perspective view of the efficient traditionally appearing ceiling fan blade 1 with aerodynamical upper surfaces 50 and wide tip end 10 of FIG. 1A with labeled cross-sections A, B, C, D, E, F, G, H, I. FIG. 3 is another top view of the efficient traditionally appearing ceiling fan blade 1 with aerodynamical upper surfaces 50 of FIG. 1A with labeled cross-sections A-I.
Referring to FIGS. 2-3 , blade 1 has an overall length of approximately 20″ and a width that varies from the root end 20 being approximately 3.53″ to the tip end 10 being approximately 4.53″. Cross-section A is taken at the tip end 10 with cross-section B approximately 1″ in and cross-sections C, D, E, F, G, H spaced approximately 3″ apart from one another. Cross-section I is taken a root end 20 with cross-section H approximately 1″ from root end 20 . FIGS. 4A-4I are individual cross-sectional views of FIGS. 2-3 taken in the direction of arrow C
FIG. 4A shows the cross-section A of FIGS. 2-3 having a width of approximately 4.53″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.27″ to a maximum thickness of the section A being approximately 0.32″ that is spaced approximately 1.82″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.29″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4B shows the cross-section B of FIGS. 2-3 having a width of approximately 4.48″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.26″ to a maximum thickness of the section B being approximately 0.31″ that is spaced approximately 1.78″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.29″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4C shows the cross-section C of FIGS. 2-3 having a width of approximately 4.33″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.24″ to a maximum thickness of the section C being approximately 0.30″ that is spaced approximately 1.99″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.29″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4D shows the cross-section D of FIGS. 2-3 having a width of approximately 4.18″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.24″ to a maximum thickness of the section D being approximately 0.29″ that is spaced approximately 1.90″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.28″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4E shows the cross-section E of FIGS. 2-3 having a width of approximately 4.03″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.23″ to a maximum thickness of the section E being approximately 0.28″ that is spaced approximately 1.81″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.27″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4F shows the cross-section F of FIGS. 2-3 having a width of approximately 3.88″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.22″ to a maximum thickness of the section F being approximately 0.27″ that is spaced approximately 1.73″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.26″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4G shows the cross-section G of FIGS. 2-3 having a width of approximately 3.73″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.22″ to a maximum thickness of the section G being approximately 0.27″ that is spaced approximately 1.70″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.25″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4H shows the cross-section H of FIGS. 2-3 having a width of approximately 3.58″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.21″ to a maximum thickness of the section H being approximately 0.27″ that is spaced approximately 1.63″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.26″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
FIG. 4I shows the cross-section I of FIGS. 2-3 having a width of approximately 3.53″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 40 TE sloping upward along a convex curve to a halfway thickness of approximately 0.21″ to a maximum thickness of the section I being approximately 0.26″ that is spaced approximately 1.60″ from the rounded leading edge 30 LE. A halfway thickness of approximately 0.24″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 30 LE.
Second Embodiment Large Diameter Blades
The labeled components will now be described.
101 novel large diameter blade 105 dotted lines for motor mount arm connection 110 tip end 120 root end 130 LE leading edge 140 TE trailing edge 150 upper surface 160 lower surface
FIG. 5 is a top perspective view of a second embodiment of a large efficient traditionally appearing ceiling fan blade 101 with aerodynamical upper surfaces 150 and wide tip end 110 with labeled cross-sections A, B, C, D, E, F, G, H. FIG. 6 is a top view of the large efficient traditionally appearing ceiling fan blade 101 with aerodynamical upper surfaces 150 of FIG. 5 with labeled cross-sections A-H.
Referring to FIGS. 5-6 , blade 101 has an overall length of approximately 21.08″ and a width that varies from the root end 120 being approximately 4.85″ to the tip end 110 being approximately 5.95″Cross-section A is taken at the tip end 110 with cross-section B approximately 1″ in and cross-sections C, D, E, F, G spaced approximately 3.96″ apart from one another. Cross-section H is taken a root end 120 with cross-section G approximately 1″ from root end 120 . FIGS. 4A-4H are individual cross-sectional views of FIGS. 5-6 taken in the direction of arrow C.
FIG. 7A shows the cross-section A of FIGS. 5-6 having a width of approximately 5.95″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.33″ to a maximum thickness of the section A being approximately 0.41″ that is spaced approximately 2.70″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.39″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 7B shows the cross-section B of FIGS. 5-6 having a width of approximately 5.90″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.32″ to a maximum thickness of the section B being approximately 0.41″ that is spaced approximately 2.70″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.39″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 7C shows the cross-section C of FIGS. 5-6 having a width of approximately 5.70″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.31″ to a maximum thickness of the section C being approximately 0.40″ that is spaced approximately 2.60″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.38″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 7D shows the cross-section D of FIGS. 5-6 having a width of approximately 5.50″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.31″ to a maximum thickness of the section D being approximately 0.39″ that is spaced approximately 2.46″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.36″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 7E shows the cross-section E of FIGS. 5-6 having a width of approximately 5.30″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.31″ to a maximum thickness of the section E being approximately 0.37″ that is spaced approximately 2.38″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.35″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 7F shows the cross-section F of FIGS. 5-6 having a width of approximately 5.10″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.29″ to a maximum thickness of the section F being approximately 0.36″ that is spaced approximately 2.29″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.35″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 7G shows the cross-section G of FIGS. 5-6 having a width of approximately 4.90″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.30″ to a maximum thickness of the section G being approximately 0.36″ that is spaced approximately 2.24″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.33″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 7H shows the cross-section H of FIGS. 5-6 having a width of approximately 4.85″, a flat bottom and an aerodynamic upper surface that starts from blunt trailing edge 140 TE sloping upward along a convex curve to a halfway thickness of approximately 0.29″ to a maximum thickness of the section H being approximately 0.35″ that is spaced approximately 2.22″ from the rounded leading edge 130 LE. A halfway thickness of approximately 0.33″ is located on a downwardly convex curve slope between the maximum thickness point and the rounded leading edge 130 LE.
FIG. 8A is a perspective bottom view of a ceiling fan 200 and efficient blades 1 / 101 of FIGS. 1-7I , with the blades 1 / 101 attached a ceiling mounted motor 210 . FIG. 8B is a perspective top view of the ceiling fan 200 and efficient blades 1 / 101 of FIG. 8A . FIG. 8C is a side perspective view of the ceiling fan 100 and efficient blades 1 / 101 of FIG. 8A . FIG. 8D is a bottom view of the ceiling fan 200 and efficient blades 1 / 101 of FIG. 8A . FIG. 8E is a top view of the ceiling fan 200 and efficient blades 1 / 101 of FIG. 8A .
Referring to FIGS. 8A-8E , one viewing beneath the ceiling fan would see bottom surfaces 60 / 160 that appear to be traditionally flat/planar ceiling fan blades. With the aerodynamical upper surfaces 50 / 150 not visible from ground level. The novel blades 1 / 101 can be mounted at angles or twisted by respective mounting arms 250 to further maximize airflow.
Third Embodiment Rounded Wide Tip End Blades
The labeled components will now be described.
301 novel efficient aerodynamic blade with rounded tip end 305 dotted lines for motor mount arm connection 310 tip end 320 root end 330 LE leading edge 340 TE trailing edge 350 upper surface 360 lower surface
FIG. 9A is a top perspective view of a third embodiment efficient traditionally appearing ceiling fan blade 301 with aerodynamical upper surfaces 350 and rounded wide tip end 310 . FIG. 9B is a bottom perspective view of the blade 301 of FIG. 9A . FIG. 9C is a top planar view of the blade 301 of FIG. 9A . FIG. 9D is a bottom planar view of the blade 301 of FIG. 9A . FIG. 9E is a left side view of the blade 301 of FIG. 9A along arrow 9 E. FIG. 9F is a right side view of the blade of FIG. 9A along arrow 9 F. FIG. 9G is a tip end 310 view of the blade 301 of FIG. 9A along arrow 9 G. FIG. 9H is a root end 320 view of the blade 301 of FIG. 9A along arrow 9 H. Referring to FIGS. 9A , 9 H, the third embodiment has similar attributes to that of the preceding embodiments with the addition of having the tip end 310 being rounded.
Fourth Embodiment Curved Wide Tip End Blades
The labeled components will now be described.
401 novel efficient aerodynamic blade with curved tip end 405 dotted lines for motor mount arm connection 410 tip end 420 root end 430 leading edge 440 trailing edge 450 upper surface 460 lower surface
FIG. 10A is a top perspective view of a fourth embodiment efficient traditionally appearing ceiling fan blade 401 with aerodynamical upper surfaces 450 and curved wide tip end 410 . FIG. 10B is a bottom perspective view of the blade 401 of FIG. 10A . FIG. 10C is a top planar view of the blade 401 of FIG. 10A . FIG. 10D is a bottom planar view of the blade 401 of FIG. 10A . FIG. 10E is a left side view of the blade 401 of FIG. 10A along arrow 10 E. FIG. 10F is a right side view of the blade 401 of FIG. 10A along arrow 10 F. FIG. 10G is a tip end 410 view of the blade of FIG. 10A along arrow 10 G. FIG. 10H is a root end 420 view of the blade of FIG. 10A along arrow 10 H. Referring to FIGS. 10A-10H , the fourth embodiment has similar attributes to that of the preceding embodiments with the addition of having the tip end 410 being curved.
Fifth Embodiment Separately Attachable Aerodynamic Surface
The labeled components will now be described.
501 novel blade with attachable upper aerodynamic surface 560 tip end 570 root end 530 leading edge 540 trailing edge 550 Separately attachable aerodynamic upper surface 505 Lower traditional flat planar sided blade 509 Fastener
FIG. 11 is tip end exploded view of a separate attachable aerodynamic surface form 550 that can be attached to conventional flat-planar surface ceiling fan blades 505 . FIG. 12 is another view of FIG. 11 with the aerodynamic surface 550 attached to the blade 505 . A traditional blade 505 can have existing flat/planar upper surface 510 and flat/planar lower surface 520 . A separate form 550 can have a flat lower surface 555 , and aerodynamic upper surface 557 . The lower surface 555 can be attached to the existing upper flat/planar surface 510 of the traditional blades 505 by glue, cement, and the like, and/or using fasteners 509 such as but not limited to screws, and the like, where the resulting blade 501 can have similar dimensions and the resulting benefits as the previous embodiments described above.
FIG. 13 is another version 581 of the separately attachable aerodynamic surface 580 with blade 560 / 570 . The add-on 580 can have an upper aerodynamic surface that slopes upward from trailing edge 582 and curves down to an overhanging rounded leading edge 588 to fit about the leading edge of the underlying flat blade 560 / 570 . The add-on can be attached similar to the add-on previously described.
The preferred embodiments can be used with blades that rotate clockwise or counter-clockwise, where the blades can be positioned to maximize airflow in either rotational directions.
While the preferred embodiment includes providing aerodynamic surfaces on the upper surface of planar/flat bladed fans, the invention can be practiced with other ceiling fan blades that can achieve enhanced airflow and efficiency results. For example, design and aesthetic appearing blades can include upper surfaces that have the efficient aerodynamic efficient surfaces.
The blade mounting arms can also be optimized in shape to allow the blades to optimize pitch for optimal airflow with or without the efficient aerodynamic upper surface blades.
Although the preferred embodiments show the efficient aerodynamic surfaces on the top of the blades, the blades can alternatively also have aerodynamic efficient surfaces on the bottom side. Alternatively, both the top and bottom surfaces can have the novel aerodynamic efficient surfaces.
While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended. | Efficient traditionally appearing ceiling fan blades with aerodynamical upper surfaces and wide tip ends for ceiling fans with blades formed from plastic and/or wood and/or separately attached surfaces that run at reduced energy consumption that move larger air volumes than traditional flat shaped ceiling fan blades. And methods of operating the novel ceiling fans blades for different speeds of up to and less than approximately 250 rpm. The novel blades twisted blades can be configured for ceiling fans having any diameters from less than approximately 32 inches to greater than approximately 64 inch fans, and can be used in two, three, four, five and more blade configurations. The novel fans can be run at reduced speeds, drawing less Watts than conventional fans and still perform better with more air flow and less problems than conventional flat type conventional flat and planar upper and lower surface blades. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to an electrophotographic apparatus, such as a laser beam printer and a copying machine, whose toner hoppers and developers can be replaced by its user or a maintenance engineer.
Referring to FIG. 7 , the general configuration of a laser printer whose toner hopper 1 and a developer 2 can be replaced by its user will be explained. For example, an electrophotographic apparatus is typically equipped with one or more printing sections comprising a photoreceptor 8 , a charger 9 that electrically charges the surface of the photoreceptor 8 , an optical scanning section 10 that optically scans the surface of the charged photoreceptor 8 with a laser beam, a developer 2 that develops image areas that are scanned optically, a toner hopper 1 that supplies toner 11 to said developer 2 , and an image transfer unit 13 that transfers the developed image to a recording member 12 . With such an arrangement, it is possible to print multi-color images on a single laser printer by replacing the set of elements consisting of the toner hopper 1 and the developer 2 . This is also applicable to MICR toner (toner for magnetic ink character recognition).
In the above-described laser printer, a user or a maintenance engineer replaces the toner hopper 1 and the developer 2 . At the time of this replacement, the toner hopper 1 (for example, containing red toner) may be combined with the wrong developer 2 (for example, containing a blue toner), so that the image printing may fail. To prevent this, various contrivances have been proposed.
Referring to FIG. 8 , one of the conventional techniques used in full-color laser printers will be explained. This example is comprised of a slit disk 16 that is mounted on the shaft of a rotating means 15 disposed in a toner cartridge 14 , which disk 16 has some equally-spaced slits on its circumference; a photo sensor that is provided opposite to the slit disk 16 to detect the presence of respective slits of the disk 16 as the disk rotates; a pulse signal generator 18 that generates a pulse signal responsive to detection of each slit of the disk 16 as the disk rotates; and a detector 3 that detects the kind of a toner cartridge 14 from the pulse signal. Generally, a full-color laser printer contains four printing sections which provide for use of four kinds of toner (yellow, magenta, cyan, and black) to form color images. Therefore, the laser printer requires four toner cartridges 14 . Similarly, the pulse signal generator 18 must have four slit disks 16 that have different slit intervals to distinguish the toner cartridges 14 properly. (For example, see Japanese Application Patent Laid-Open Publication No. 2001-255728 (Page 3–7, FIG. 3))
Referring to FIG. 9 , a general technique for effecting proper combination of a toner hopper and a developer will be explained. FIG. 9A shows a means to prevent a wrong combination of toner hoppers and developers. FIG. 9B shows examples of a key configuration used for this purpose. In FIG. 9A , plural keys 19 are provided in the part where the toner hopper 1 is connected to the developer 2 to prevent wrong hopper-developer combinations. FIG. 9 B-(i a) shows the shape of a key 20 for a toner hopper containing red toner and the shape of a key 21 of the developer 2 containing red toner. The projection and recess of these keys are formed to fit each other. Similarly, FIG. 9 B-( b ) shows the shape of a key 22 for a toner hopper containing blue toner and the shape of a key 23 of the developer 2 containing blue toner. The projection and recess of these keys are formed to fit each other. However, in FIG. 9 B-( c ), it can be seen that the key 22 of the toner hopper containing blue toner does not fit to the key 21 of the developer 2 containing red toner.
Generally, a full-color laser printer uses four kinds of toner (yellow, magenta, cyan, and black) to form full color images. In other words, the printer requires four toner hoppers and four developers. Therefore, a spot color printer that has at least one printing section and forms images without mixing toners must prepare some dozens of toner colors to meet a user's requests.
SUMMARY OF THE INVENTION
Usually, a laser printer generally stores information concerning the quantity of consumption to indicate the timing to replace expendables and specific control values in a non-volatile memory. This procedure is also applicable to the toner hoppers and developers. In the case of a printer which has a toner hopper and a developer that cannot be replaced, the printer stores information concerning the quantity of toner consumption related to the toner hopper and the developer and specific control values in a non-volatile memory on a control board in the printer. On the other hand, in the case where the toner hopper and the developer are replaceable, such information and specific control values before and after replacement may be mixed up after the toner hopper and the developer are replaced, if the printer stores such information and values at an address of the non-volatile memory on the control board. To avoid this, conventional printers use a method of providing a non-volatile memory in their toner hoppers or developers. When a developer has a non-volatile memory, the data in the non-volatile memory contains information concerning a corresponding toner hopper. For example, when a printer has two sets of a toner hopper and a developer for red toner, information of one of the red toner hoppers is stored in the non-volatile memory of the corresponding developer only. If this red toner hopper is connected to the other developer, different control may result from wrong information. In other words, when a spot color printer or the like has at least one printing section and does not mix toners to form color mages, only providing means to distinguish toner hoppers and developers for respective colors is not enough. If the user requires some dozens of toner colors, the printer must provide further means to distinguish them.
However, the above-described conventional technology must provide very complicated slit disks and many hopper-developer engagement keys. This technology makes the printer product very expensive (because of the costs to make the slit disks and key dies).
An object of this invention is to provide an electrophotographic apparatus that can detect hopper-developer correspondences by use of electric signals of the toner hoppers and the developers without using many complicated and expensive parts to detect such correspondences.
The above-stated object can be attained by providing a means such as a DIP switch or non-volatile memory to output electric signals on each of the toner hoppers and the developers, assigning codes corresponding to toner colors to electric signals, and detecting the correspondences of toner hoppers and developers by use of the electric signals.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram which shows an embodiment of this invention, in which a toner hopper and a developer respectively contains a DIP switch.
FIG. 2 is a block diagram which shows an embodiment of this invention, in which a toner hopper contains a DIP switch and a developer contains a non-volatile memory.
FIG. 3 is a block diagram which shows an embodiment of this invention, in which a toner hopper and a developer respectively contain a non-volatile memory.
FIGS. 4A and 4B are diagrams which show an example of assignment of 8-bit data codes to a toner hopper and a developer according to toner colors.
FIGS. 5A and 5B are diagrams which show an example of assignment of 4-bit data codes to toner hoppers and developers according to toner colors and assignment of set codes to toner hoppers and developers of the same color, if any.
FIG. 6 is a schematic diagram which shows an example of the configuration of a DIP switch circuit whose bits represent a code of a toner hopper in accordance with the embodiment of this invention.
FIG. 7 is a schematic diagram of an electrophotographic processing apparatus.
FIG. 8 is a diagram which shows a configuration of a conventional means to detect the correspondence of a toner cartridge using a slit disk.
FIGS. 9A and 9B are diagrams which show conventional means to mechanically prevent a wrong combination of a toner hopper and a developer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 , an embodiment concerning first and second aspects of this invention will be explained. The toner hopper 1 and the developer 2 , respectively, have a DIP switch 4 which is connected to a detecting section comprising a CPU, a memory, and a logical circuit. For example, when the DIP switches are respectively 8 bits long, a hexadecimal code “01h” is assigned to a black toner hopper 1 and a developer 2 that contains black toner. Similarly, a hexadecimal code “02h” is assigned to a red toner hopper 1 and a developer 2 that contains red toner. The DIP switches are respectively set to “01h” and “02h.”
When the black toner hopper 1 is engaged with the developer 2 containing black toner, the DIP switch 4 in the black toner hopper 2 outputs code “01h” and the DIP switch 4 in the developer 2 containing a black toner outputs code “01h,” too. These codes “01h” are output to the detector 3 . When the same codes “01h” are received from the toner hopper 1 and the developer 2 , the detector judges that the toner hopper 1 and the developer 2 are correspond to each other and permits the laser printer to start printing without outputting an error message.
However, when the black toner hoper 1 is combined with the developer 2 containing red toner, the DIP switch 4 in the black toner hopper 1 outputs code “01h” and the DIP switch 4 in the developer 2 containing red toner outputs code “02h.” These codes “01h” and “02h” are output to the detector 3 . When these different codes “01h” and “02h” are received from the toner hopper 1 and the developer 2 , the detector judges that the toner hopper 1 (including black toner) and the developer 2 (including red toner) do not correspond with each other, and so an error message is outputted, and the laser printer is not allowed to start printing.
In accordance with the third and fourth aspects of this invention, at least either the toner hopper 1 or the developer 2 has a non-volatile memory. First, with reference to FIG. 2 , a case in which only the developer 2 has a non-volatile memory 5 will be explained. The toner hopper 1 has a DIP switch 4 and the developer 2 has a non-volatile memory 5 . The DIP switch 4 and the non-volatile memory 5 are respectively connected to a detector 3 comprising a CPU, memory, and a logic circuit. For example, when the DIP switch 4 and the non-volatile memory 5 are respectively 8 bits long, a hexadecimal code “01h” is assigned to a black toner hopper 1 and to a developer 2 that contain a black toner. Similarly, a hexadecimal code “02h” is assigned to a red toner hopper 1 and to a developer 2 that contains red toner. The DIP switch 4 in the toner hopper 1 is set to code “01h” and data at a preset address in the non-volatile memory in the developer 2 is set to “02h.” To check the hopper-developer correspondence, the detector checks the codes sent as electric signals from the toner hopper and the developer 2 in a similar way and permits the printer to start printing when the codes are identical or does not allow the printer to start printing when the codes are different. This is applicable also when only the toner hopper 1 has a non-volatile memory.
FIG. 3 shows a case in which both the toner hopper 1 and the developer 2 have a non-volatile memory 5 . These non-volatile memories are respectively connected to a detector comprising a CPU, memory, and a logic circuit.
For example, when the data lengths of the non-volatile memories 5 are each 8 bits long, a hexadecimal code “01h” is assigned to a black toner hopper 1 and to a developer 2 that contains black toner. Similarly, a hexadecimal code “02h” is assigned to a red toner hopper 1 and to a developer 2 that contains red toner. The contents at preset addresses in the non-volatile memories of the toner hopper 1 and the developer 2 are respectively set to “01h” and “02h.” To check the hopper-developer correspondence, the detector checks the codes sent as electric signals from the toner hopper and the developer 2 in a similar way and permits the laser printer to start printing when the codes are identical or does not allow the printer to start printing when the codes are different. Further, when the toner hopper 1 or the developer 2 has both a DIP switch 4 and a non-volatile memory 5 , a code can be assigned to any of them.
A fifth aspect of this invention is related to the assignment of said codes. FIGS. 4A and 4B show examples of an 8-bit code assignment to a toner hopper 1 and to a developer 2 . In FIG. 4A , each toner color is assigned to each data bit. For example, black, red, and blue are assigned to bit 0 , bit 1 , and bit 2 in that order. Other toner colors can be assigned to the other data bits in a similar manner. This enables recognition of toner hoppers 1 and developers 2 for toners of eight colors.
In FIG. 4B , color codes are assigned to combinations of data bits instead of by bit-by-bit assignment. You can assign 256 colors by assigning each color to a respective hexadecimal value, for example, black to “01h,” red to “02h,” blue to “03h,” and so on including “00h” and “FFh”, or 254 colors not including “00h” and “FFh.”
A sixth aspect of this invention uses set codes in the assignment of color codes when the printer has a plurality of toner hoppers and a plurality of developers that contain toners of identical colors. FIGS. 5A and 5B show examples of the assignment of color codes of four data bits long and set codes of four data bits long to the toner hoppers 1 and the developers 2 . In FIG. 5A , toners of respective colors are assigned in bits, and, further, it is possible to recognize toner hoppers 1 and developers 2 for four toner colors and four sets of toner hoppers 1 and developers 2 of the same color by assigning bit 4 to the first set of a toner hopper 1 and a developer 2 of the same color, bit 1 to the second set, bit 2 to the third set and so on. For example, when the first set of the yellow toner hopper 1 and the developer 2 for yellow toner are used, bits 3 and 4 are selected and code “18h” is output. When the second set of the yellow toner hopper 1 and the developer 2 for a yellow toner are used, bits 3 and 5 are selected and code “28h” is output. In this way, it is possible to distinguish the toner hopper 1 and the developer 2 from those of the same color.
In FIG. 5B , toner colors are assigned to combinations of data bits, and further, it is possible to assign toner hoppers 1 and developers 2 for 16 toner colors and 16 sets of toner hoppers 1 and developers 2 of the same color, for example, by assigning “10h” to the first set of a toner hopper 1 and a developer 2 of the same color, “20h” to the second set, and so on, including “00h” and “FFh”, or toner hoppers 1 and developers 2 for 16 toner colors and 16 sets of toner hoppers 1 and developers 2 of the same color and the like, not including “00h” and “FFh.” For example, when the first set of a red toner hopper 1 and a developer 2 for red toner is selected, a code “12h” is output. When the second set of a red toner hopper 1 and a developer 2 for red toner is selected, a code “22h” is output. In this way, it is possible to distinguish the toner hopper 1 and the developer 2 from those of the same color.
In accordance with a seventh aspect of this invention, codes to toner hoppers 1 and developers 2 are assigned independently of toner colors. When data of the DIP switches 4 or non-volatile memory 5 in the toner hoppers 1 and the developers 2 are respectively 8 bits long, it is possible to distinguish toner hoppers 1 and developers 2 of the same colors. For example, assuming a purchase has been made of toner hoppers 1 and developers 2 for a blue toner, a red toner, a black toner, and again a red toner in this order, it is possible to distinguish them by assigning “01h” to those for a blue toner, “02h” to those for a red toner, “03h” to those for a black toner, and “04h” to the second set of a toner hopper and a developer for a red toner.
According to an eighth aspect of this invention, codes that generate electric signals of all zeros or all ones are not assigned to toner hoppers 1 and developers 2 . In other words, when data of the DIP switches 4 or non-volatile memory 5 in the toner hoppers 1 and the developers 2 are respectively 8 bits long, only codes “01h” to “FEh” are available. The reason for this will be explained below with reference to FIG. 6 . FIG. 6 shows an example of a circuit containing a DIP switch of 8 bits long to determine the code of a toner hopper 1 . One end of each data bit of the DIP switch is grounded and the other end of each bit is connected to a detector 3 through a connector 6 . Each signal is pulled up to Vcc through a resistor 7 . In this circuit configuration, each bit becomes “0” when its micro-switch of the DIP switch 4 is turned on or becomes “1” when its micro-switch of the DIP switch 4 is turned off. If you assign a code “FFh” that generates an electric signal of all ones to a black toner hopper 1 , you cannot tell it from another signal pattern “FFh” that represents a disconnection of the connector 6 . When a code that generates an electric signal of all zeros or all ones is not assigned, it is possible to easily recognize a disconnection of the connector 6 (that is a disconnection of the toner hopper).
As explained above, this invention enables detection of correspondences of toner hoppers 1 and developers 2 by use of electric signals generated by the toner hoppers 1 and the developers 2 , instead of using a lot of complicated parts to detect correspondences of toner hoppers 1 and developers 2 .
In accordance with this invention, an electrophotographic apparatus can detect correspondences of toner hoppers and developers by providing a means, such as a DIP switch or non-volatile memory, to output electric signals that are coded according to toner colors or the like on respective toner hoppers and by developers and using the electric signals instead of using a lot of complicated parts. | An electrophotographic apparatus is equipped with one or more printing sections including a photoreceptor, a charger that electrically charges the surface of the photoreceptor, an optical scanning section that optically scans the surface of the charged photoreceptor with a laser beam, a developer that develops image areas formed by optical scanning, a toner hopper that supplies toner to the developer, and an image transfer unit that transfers the developed image to a recording member. In this apparatus, the developer and toner hopper can be mounted and demounted separately and a plurality of toner hoppers and developers are changeable according to the kinds of toner colors to be used. Thus, of the developers and toner hoppers is equipped with a device that outputs electric signals to detect the correspondences of the toner hoppers and the developers. | 6 |
TECHNICAL FIELD
The present invention relates to systems and methods for controlling induction motors.
BACKGROUND
One of the most common methods for controlling induction motors is known in the art as indirect rotor flux orientation control. Continuous feedback of motor operation information and various motor parameters are required using this method. For example, rotor position feedback, rotor resistance and inductance are required parameters using this method. Sensor wheels and position sensors are typically used to determine rotor position. Proper slip frequency is maintained based upon rotor resistance, rotor inductance, and phase current. The motor torque can be calculated by measuring the motor current for a given condition.
This type of control methodology is simple and crude. One significant problem that arises using this method of control is that rotor resistance and rotor inductance is affected by the temperature and magnetic saturation and thus the motor performance is affected as well. Typically, however, it is assumed that rotor resistance and inductance stays constant for all conditions. This assumption is, of course, incorrect and thus the performance of the motor suffers when the rotor is hot.
While there are systems and methods for providing position sensorless control of induction motors, they are typically complicated and their effectiveness varies as motor operating conditions change. Generally, complicated math filters or observers are used to estimate critical motor parameters, such as, rotor resistance, rotor inductance, rotor electrical frequency, etc. As the result, the inaccuracy of estimations greatly effects the motor's performance. Thus they do not provide optimal dynamic motor control.
Therefore, there exists a need for a new and improved method and system for controlling an induction motor. The new and improved method and system should not depend on continuous position sensor feedback and various motor parameters, since these parameters vary with temperature, magnetic saturation, and motor wear. Further, the new and improved system should allow the motor to operate continuously in an optimized range, require minimum calibration, and accommodate for high motor parameter variation tolerance.
SUMMARY
A method for controlling an induction motor using an equivalent circuit model is provided. The equivalent circuit includes a real resistive component and an imaginary inductive component. The method avoids measuring or estimating individual induction motor parameters, instead, only a few operating parameters, such as phase voltages and phase currents are measured to determine a lump sum of the real and imaginary components of the induction motor impedance. Then, a first control function based on the real component of the induction motor impedance is calculated, a second control function based on the imaginary component of the induction motor impedance is calculated. Then, the induction motor excitation frequency is adjusted until the first control function is approximately equal to the second control function. Finally, the magnitude of the phase voltage is varied to achieve the desired motor/generator performance.
In an aspect of the present invention, determining the real component of the induction motor impedance includes calculating the real component of the induction motor impedance using the equation:
Real( Z in )=( V ds i ds +V qs i qs )/( i ds 2 +i qs 2 ).
In another aspect of the present invention, determining the imaginary component of the induction motor impedance includes calculating the imaginary component of the induction motor impedance using the equation:
Im ( Z in ) j =( V qs i ds −V ds i qs )/( i ds 2 +i qs 2 ).
In still another aspect of the present invention, when the motor is used to convert electrical power to mechanical power, herein referred to as motoring mode, the first control function is calculated using the equation:
A′=K
m
−A.
In still another aspect of the present invention, when motor is used to convert mechanical power to electrical power, herein referred to as generation mode, the first control function is calculated using the equation:
A′=K
g
+A.
In still another aspect of the present invention, calculating a second control function further includes calculating using the following equation for both motoring and generation modes:
B′=B /( W e K o ).
In still another aspect of the present invention, adjusting an induction motor operating parameter further includes adjusting an excitation frequency.
In still another aspect of the present invention, at the above determined stator excitation frequency, adjusting the amplitude of the voltage applied to motor results in the desired motor torque as described by the equation: T e = 3 P ( Real ( Z in ) - R s ) ( V 2 ) W e ( ( Real ( Z in ) ) 2 + ( Im ( Z in ) ) 2 ) ( 3 )
These and other aspects and advantages of the present invention will become apparent upon reading the following detailed description of the invention in combination with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of an induction motor with an internal combustion engine forming a hybrid powerplant, in accordance with the present invention
FIG. 2 is a schematic diagram illustrating an induction motor, in accordance with the present invention;
FIG. 3 is an equivalent electrical circuit model of the induction motor, in accordance with the present invention;
FIGS. 4 a and 4 b are graphs illustrating a torque output curve, efficiency curve and respective induction motor control signals, wherein the motor is operating in motoring mode at an optimum state, in accordance with the present invention;
FIGS. 4 c and 4 d are graphs illustrating a torque output curve, efficiency curve and respective induction motor control signals, wherein the motor is operating in generating mode at an optimum state, in accordance with the present invention;
FIG. 5 is a flowchart of a control strategy for controlling the operation of an induction motor, in accordance with the present invention.
DETAILED DESCRIPTION
The system and method of the present invention will be described and illustrated in a hybrid motor environment. Of course, it should not be construed that this is the only environment or application in which the present invention may be applied. On the contrary, the system and method of the present invention may be used in any application where an induction motor is implemented.
With reference to FIGS. 1 and 2, a perspective view of a hybrid automotive engine 10 is illustrated, in accordance with the present invention. Hybrid engine 10 preferably includes an internal combustion engine 12 mechanically coupled to an induction motor 14 . More specifically, induction motor 14 is in rotational communication with the crankshaft of engine 12 and is preferably positioned between the engine block of engine 12 and the transmission. Induction motor 14 advantageously combines the functions of the starter and the alternator. Thus, many benefits and advantages are realized, such as seamless starting and stopping of engine 12 , high efficiency electricity generation, and active damping of powertrain vibrations.
More specifically, induction motor 14 has a motor housing 16 which includes mounting features such as through apertures 18 for fixedly securing motor housing 16 to engine 12 . Further, induction motor 14 has a stator 20 fixedly mounted to motor housing 16 , and a rotor 22 , rigidly coupled to the crankshaft (not shown) of engine 12 . A stator winding 24 are disposed about stator 20 . Rotor 22 is concentrically disposed within stator 20 and rotates with the engine's crankshaft (not shown). Additionally, an air gap 32 is defined by an outer surface 19 of rotor 22 and an inner surface 21 of stator 20 .
A transmission (not shown) for transmitting drive torque to a vehicle's road wheels would be mounted to motor housing 16 and coupled through a driveshaft to a rotor gear spline 30 on rotor 22 .
Induction motor 14 operates in at least two modes: a motoring mode, where electrical power is converted to mechanical power, and a generation mode where mechanical power is converted to electrical power. When induction motor 14 is operating in motoring mode, a three-phase alternating current is supplied to stator winding 24 directly and to rotor 22 by induction or a transformer action from the stator winding. The application of this poly-phase signal source to stator winding 24 , produces a magnetic field in air gap 32 between rotor 22 and stator 20 . The magnetic field rotates at a speed determined by the number of poles of stator 20 (a 12 pole machine is utilized in this invention) and the applied stator winding frequency (W e ). The rotor is made of a so-called squirrel cage rotor having windings consisting of conducting bars embedded in slots in the rotor iron and short circuited at each end by conducting end rings. The extreme simplicity and ruggedness of the squirrel cage construction are outstanding advantages of this type of induction motor.
The present invention provides a control strategy for controlling the operation of induction motor 14 . The control strategy of the present invention provides sensorless control by measuring the impedance (Z in ) of induction motor 14 to calculate the proper stator winding frequency (W e ) and to achieve the required torque (T e ) to rotate the rotor 22 and thus the crankshaft of engine 12 . The impedance and torque equations below illustrate how the control strategy of the present invention avoids reliance on critical motor parameters, that will change over varying operating conditions, as well as over the operating life of induction motor 14 . Thus, the present invention provides robust motor control whereby the system continuously operates in an optimized torque or efficiency range regardless motor parameter variations.
With reference to FIG. 3, an electrical equivalent circuit model 30 of induction motor 14 is illustrated. An impedance (Z in ) of motor 14 includes a stator resistance (R s ) 32 , a stator leakage inductance (L 1 ) 34 , a rotor leakage inductance (L 2 ) 36 , a magnetizing inductance (L m ) 38 and a rotor resistance converted to stator side (R r /s) 40 . Furthermore, the impedance (Z in ) of motor 14 is comprised of real Real(Z in ) and imaginary Im(Z in ) components as shown in the equation (1) below:
Z in =Real( Z in )+ Im ( Z in ) j (1)
or
Z in =( R s +[(R r L m 2 W e W sl )/( R r 2 +L r 2 W sl 2 )])+ j ( L s W e −[( L m 2 L r 2 W sl 2 )]) (2)
The theoretical induction motor torque (T e ) is described by the following equation: T e = 3 P L m 2 ( R r / S ) W e ( V 2 ) 2 [ ( R s 2 + L s 2 W e 2 ) ( ( R r 2 / S 2 ) + L r 2 W e 2 ) +
L m 2 W e 2 ( 2 R s ( R r / S ) - 2 L s L r W e 2 + L m 2 W e 2 ) ]
By substituting Real(Z in ) and Im(Z in ), the torque equation is simplified to: T e = 3 P ( Real ( Z in ) - R s ) ( V 2 ) W e ( ( Real ( Z in ) ) 2 + ( Im ( Z in ) ) 2 ) ( 3 )
Where:
W e =the excitation frequency;
W r =the rotor frequency;
W sl =W e −W r is the slip frequency;
V=Phase Voltage;
R s =the stator resistance;
R r =the rotor resistance;
L 1 =the leakage inductance of the stator;
L 2 the leakage inductance of the rotor;
L m =the magnetizing inductance;
L s =L 1 +L m is the total stator inductance;
L r =L 2 +L m is the total rotor inductance;
P=number of pole pairs of the motor;
T e =the electromagnetic torque;
S=(W e −W r )/W e is the slip;
L σ =(L s L r −L m 2 )/L r is the total leakage inductance; and
λ dr &λ qr are the flux linkages in the d-q frame.
The conventional induction motor (d-q) machine model as described in an article entitled “Control Development and Characterization of the Induction Machine Starter/Alternator Drive Module (IMSAM)”, a Phase III Report for the Ford HEV Program, by Xu, et al, pages 1-7, hereby incorporated by reference is applied. Moreover, the stator current, rotor flux, and rotor frequency are used as the state variables and assuming steady state operation yields the following equations: L σ ( di ds / dt ) = 0 = - ( R s + ( L m 2 / L r 2 ) R r ) i ds + ( L σ W e i qs ) + ( L m / T r L r ) λ dr + W r ( L m / L r ) λ qr + V ds ( 4 ) L σ ( di qs / dt ) = 0 = - ( R s + ( L m 2 / L r 2 ) R r ) i qs - ( L σ W e i ds ) - W r ( L m / L r ) λ dr + ( L m / T r L r ) λ qr + V qs ( 5 )
T r ( dλ dr /dt )=0= L m i ds −λ dr +T r W sl λ qr (6)
T r ( dλ qr /dt )=0 =L m i qs −λ qr −T r W sl λ dr (7)
T e (3 PL m )(λ dr i qs −λ qr i ds )/(2 L r ) (8)
Solving Equations (6) and (7) for Xdr and Xqr yields the following:
λ dr =( L m i ds +T r W sl L m i qs )/(1 +T r 2 W sl 2 ) (9)
λ qr =( L m i qs −T r W sl L m i ds )/(1 +T r 2 W sl 2 ) (10)
Also: T r =L r /R r (11)
W r =W e =W sl (12)
Substituting into Equations (9)-(12) into Equations (4) and (5): 0 = - ( R s + [ ( R r L m 2 W e W sl ) / ( R r 2 + L r 2 W sl 2 ) ] ) i ds + ( L s W e - [ ( L m 2 L r W e W sl 2 ) / ( R r s + L r 2 W sl 2 ) ] ) i qs + V ds ( 13 ) 0 = - ( L s W e - [ ( L m 2 L r W e W sl 2 ) / ( R r 2 + L r 2 W sl 2 ) ] ) / ds - ( R s + [ ( R r L m 2 W e W sl ) / ( R r 2 + L r 2 W sl 2 ) ] ) i qs + V qs ( 14 )
Let: A =( R s +[( R r L m 2 W e W sl )/( R r 2 +L r 2 W sl 2 )]) (15)
B =( L s W e −[( L m 2 L r W e W sl 2 )/( R r 2 +L r 2 W sl 2 )]) (16)
Then Equations (13) and (14) become:
V ds =( A ) i ds −( B ) i qs (17)
V qs =( B ) i ds −( A ) i qs (18)
And: A =( V ds i ds +V qs i qs )/( i ds 2 +i qs 2 ) (19)
B =( V qs i ds −V ds i qs )/( i ds 2 +i qs 2 ) (20)
Substituting Equations (15) and (16) into (2) suggests:
A→ Real( Z in )=( V ds i ds +V qs i qs )/( i ds 2 +i qs 2 ) (21)
B→Im ( Z in ) j =( V qs i ds −V ds i qs )( i ds 2 +i qs 2 ) (22)
Since V ds , V qs are controlled parameters, l qs , l ds are the motor phase currents converted to d-q frame, the motor impedance is calculated without using individual motor parameters, such as R s , L s , R r , L r and Slip. Since the variation of motor parameters affects motor phase voltage and phase current, the impedance calculated in (21) and (22) represents the actual motor operation condition and the effect of parameter changes due to motor speed, temperature change, and magnetic saturation are also included.
With reference to FIGS. 4 a and 4 b , a plot of induction motor control signals or functions 52 , 54 are illustrated for motoring mode operation. More specifically, FIG. 4 a illustrates how K m may be adjusted to achieve maximum torque. While FIG. 4 b illustrates how K m may be adjusted to achieve maximum efficiency as represented by efficiency curve 58 . In motor motoring mode, the control signals or functions 52 and 54 are defined by equations (23a) and (24) below:
A′=K m −A (23a)
B=B /( W e K o ) (24)
Where K m is a motor performance control constant, introduced purposely to cause the motor to operate in the desired range, such as optimized torque generation or maximum efficiency, and K o is a unit conversion constant used to optimize motor control as will be discussed hereinafter. Control signal 52 , as indicated by equation (23a), is derived from the real part of induction motor impedance (Z in ). Induction motor control signal 54 , as indicated by equation (24), is derived from the imaginary part of the induction motor impedance (Z in ). The stator winding excitation frequency W e , is controlled so that control function 52 approximately equals control function 54 , thus allowing the motor to operate in the desired operating range (i.e. maximum torque output or maximum efficiency).
The torque generated by induction motor 14 is shown in FIGS. 4 a and 4 b and is represented by reference numeral 56 . Control signals 52 and 54 cross at two points, namely CP 1 and CP 2 . As is clear from FIGS. 4 a and 4 b , crossing point CP 1 does not correspond with a desired torque output (maximum torque) or maximum efficiency of induction motor 14 . Accordingly, CP 1 is not used to judge whether the motor is in a desirable operating range. Further, K m is adjusted such that CP 2 corresponds with the maximum output torque of induction motor 14 or peak efficiency which depends on motor operating requirements. There always exists a relationship between CP 2 and the maximum torque point over the motor excitation speed range.
By evaluating the magnitude of motor impedance |Z in | or |I ds 2 +l qs 2 |/( V ds 2 +V qs 2 ) and the polarity of torque (T e ), the difference between crossing point CP 1 and CP 2 is easily distinguishable. Whereby only crossing point CP 2 is selected to achieve sensorless motor control.
With reference to FIGS. 4 c and 4 d , a plot of induction motor control signals or functions 62 , 64 are illustrated in generating mode. More specifically, FIG. 4 c illustrates how K g may be adjusted to achieve maximum torque. While FIG. 4 d illustrates how K g may be adjusted to achieve maximum efficiency as represented by efficiency curve 68 . In motor generation mode, the control signals or functions 62 and 64 are defined by equations (23b) and (24) below:
A′=K g +A. (23b)
B′=B /( W e K o ) (24)
Where K g is a motor performance control constant, introduced purposely to cause the motor to operate in the desired range, such as optimized torque generation or maximum efficiency, and K o is a unit conversion constant used to optimize motor control, as will be discussed hereinafter. Control signal 62 , as indicated by equation (23b), is derived from the real part of induction motor impedance (Z in ). Induction motor control signal 64 , as indicated by equation (24), is derived from the imaginary part of the induction motor impedance (Z in ). The stator winding excitation frequency W e , is controlled so that control function 62 approximately equals control function 64 , thus allowing the motor to operate in the desired operating range (i.e. maximum torque output or maximum efficiency).
The torque generated by induction motor 14 is shown in FIGS. 4 c and 4 d and is represented by reference numeral 66 . Control signals 62 and 64 cross at two points, namely CP 1 and CP 2 . As is clear from FIGS. 4 c and 4 d , crossing point CP 1 does not correspond with a desired torque output (maximum torque) or maximum efficiency of induction motor 14 . Accordingly, CP 1 is not used to judge whether the motor is in a desirable operating range. Further, K g is adjusted such that CP 2 corresponds with the maximum output torque of induction motor 14 or peak efficiency which depends on motor operating requirements. There always exists a relationship between CP 2 and the maximum torque point over the motor excitation speed range.
By evaluating the magnitude of motor impedance |Z in | or |l ds 2 +l qs 2 |/(V ds 2 +V qs 2 ) and the polarity of torque (T e ), the difference between crossing point CP 1 and CP 2 is easily distinguishable. Whereby only crossing point CP 2 is selected to achieve sensorless motor control.
Therefore, the sensorless induction motor control of the present invention is achieved by: adjusting the stator frequency W e until equation (23a) or (23b) equals equation (24) and by varying V ds and V qs in equation (3) to control the magnitude of the motor torque.
Referring now to FIG. 5, a flow chart illustrating an induction motor control strategy is illustrated, in accordance with the present invention. Control strategy 100 is initiated at block 102 , and at block 104 induction motor phase currents and phase voltages are directly measured and converted to the d-q reference frame. At block 106 , the real component of the motor impedance is calculated. The imaginary component of the motor impedance is calculated at block 108 . At block 110 , control functions A′ and B′ are calculated according to the mode the motor is operating in, whereby A′ is determined by (23) or (23a). The control function B′ is calculated by taking the imaginary component of the induction motor impedance and dividing by the product of the excitation frequency (W e ) and a unit conversion constant (K o ). Next, the difference of the control functions A′ and B′ are calculated, at block 112 . At block 114 a selection of the correct crossing point (CP 2 ) is made. At block 116 , the excitation frequency (We) is adjusted until the control function A′ approximately equals the control function B′. In practice however, the excitation frequency will be adjusted so that control function A′ is approximately equal to control function B′ within a predefined and specified range. With W e selected, the motor torque may then be calculated from (3) where V ds and V qs are the inputs.
Thus, the present invention provides a sensorless induction motor control with voltages in the d-q frame as the only inputs for achieving the desired motor performance. Instead of employing individual motor parameters, the aforementioned sensorless induction motor control strategy relies on measuring motor phase voltage and phase current, and the continuous calculation of control functions (23a), (23b), and (24), accounting for operating condition changes, temperature changes, magnetic saturation, and motor wear.
The present invention has many advantages and benefits over the prior art. For example, the impedance and torque equations described above illustrate how the control strategy of the present invention avoids reliance on critical motor parameters, that will change over varying operating conditions, as well as over the life of induction motor 14 . Still, the control parameters, K m , K g , and K 0 provide an easy means for adjusting motor operation in the desired operation range. Thus, the present invention provides a robust motor control whereby the system continuously searches for the optimized torque/efficiency range to operate the motor. | A method for controlling an induction motor using an equivalent circuit model, the equivalent circuit having a real component and an imaginary component, is disclosed. The method instead of measuring a plurality of induction motor parameters, the real and the imaginary component of the induction motor impedance are calculated based on the measured phase currents and voltages. The invention calculates a first control function based on the real component of the induction motor impedance, and a second control function based on the imaginary component of the induction motor impedance, and adjusts the induction motor excitation frequency until the first control function is approximately equal to the second control function. After the excitation frequency is determined, the motor torque is calculated by taking the square of motor voltage in the d-q reference frame. Working with a few control parameters, the present invention achieves a desired maximum torque or a desired peak efficiency with a high tolerance of variation in the control parameters. | 7 |
CROSS REFERENCE TO THE RELATED APPLICATIONS
[0001] The present disclosure is related to the application titled APPARATUS AND METHOD FOR INCREASING MONOPOLE CAPACITY USING INTERNAL STRENGTHENING filed concurrently herewith by the same inventive entity. The disclosure of such related patent application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] Antennas for over-the-air communications, such as cellular telephone systems, are usually supported on hollow tubular steel monopoles. Monopoles are located throughout most metropolitan and suburban areas. The location and density of monopoles in any particular area depend on the density of users, the elevation of the monopole sites, the height of each monopole and the coverage required. The height of each monopole can vary from only a few feet up to hundreds of feet.
[0003] As areas have more and more over-the-air communication demands, monopoles are becoming more and more numerous. Many neighborhoods are resisting the installation of monopoles with great vigor. In addition to the resistance to installation of new monopoles, many of the prime sites for monopoles have already been acquired and are thus not available for new entrants into the field, or for upgrading of an existing system. Many remaining sites are less desirable for companies seeking to enter or expand in the field of over-the-air communication. Reacting to pressure from constituents, many local governments are reluctant to grant permits for new monopoles.
[0004] Therefore, there is a need for a means for increasing over-the-air coverage while meeting the requirements placed on locating monopoles.
[0005] One way of increasing the over-the-air coverage is to increase the number of antennas available for such coverage. In view of the restrictions placed on adding new monopoles, this will require adding antennas to existing monopoles. It is possible to achieve this end using new antenna technology whereby new antennas do not need to be located as high as antennas embodying older technology. Thus, new antennas could be simply mounted onto existing monopoles and this will achieve the goal of increasing antenna coverage for an over-the-air system without requiring the placement of more monopoles.
[0006] However, this approach is not as simple as it appears at first blush. The problem with adding more antennas to an existing monopole is that such addition of antennas increases the loading on the monopole. Loading on the monopole is increased both from a dead load standpoint and from a live load standpoint.
[0007] Thus, simply adding more antennas to a monopole will increase the load on the monopole by the addition of the weight associated with the additional antennas. This weight is manifested in added compression stresses placed on the monopole.
[0008] Another problem associated with adding antennas to an existing monopole is that live loads on the monopole associated with wind loading on the antennas (both the existing antennas and the newly added antennas) will be increased by a factor determined by the wind area added to the monopole.
[0009] It is also noted that wind forces on the antennas can also cause a twisting stress on the monopole, and this stress will also be increased by the addition of antennas to the existing monopole.
[0010] The wind forces on the antennas creates both live loading on the monopole and may create a possibility of misaligning antennas. Misalignment of one antenna can be created by wind loading on other antennas on the same monopole due to the twisting or deflection of the monopole associated with such wind forces on the monopole and other antennas.
[0011] Yet another problem with simply adding antennas to an existing monopole arises because many existing monopoles have been designed for loads associated with a certain number of antennas. Thus, adding antennas and the forces associated with those additional antennas may create a situation for some existing monopoles in which the loading on the monopole is not within design parameters.
[0012] Therefore, there is a need for apparatus and methods for increasing the number of antennas that can be supported on an existing monopole whereby advantage can be taken of new antenna technology without exceeding the design limits of existing monopoles.
[0013] It may also not be possible to simply re-enforce existing monopoles by purchasing additional land to accommodate the guy wires or the like. Many municipalities have aesthetic requirements that will be violated by such guys, and some monopole sites are not large enough to include such guys. Still further, adding guys may be so expensive that it overwhelms the cost savings associated with the addition of antennas.
[0014] Therefore, there is a need for an apparatus and methods for increasing the number of antennas that can be supported on an existing monopole without requiring guy re-enforcement of the monopole.
[0015] Of course, one approach to accommodating additional antennas would be to simply replace existing monopoles with new and stronger monopoles. However, this approach may prove to be too costly to be feasible.
[0016] Therefore, there is a need for a means and a method for modifying existing monopoles to accommodate additional antennas without requiring replacement of such existing monopoles.
SUMMARY OF THE INVENTION
[0017] The inventive entity of the present invention has observed that existing monopoles are generally hollow tubular structures. These structures have been designed according to deflection limitations or to allowable stress placed on the wall of the tubular structure. The inventive entity has also observed that design calculations indicate that design stresses are well under allowable stresses when the design is based on deflection. Therefore, there will be strength available if the monopole can be stiffened to reduce deflection when antennas are added to the structure.
[0018] When design limits associated with hollow tubular structures such as monopoles are based on stress, the allowable stress is based on compression failure rather than tension failure. When antennas supported on a monopole are subject to wind forces, the forces transferred to the monopole are manifested in tension forces on some parts of the structure wall and in compression forces on other parts of the structure wall. It has also been observed that the forces associated with the weight of the antennas and the monopole are compression forces and thus added to the compression forces associated with wind loading on the antennas and the monopole. This will exacerbate any problems that may be associated with compression forces applied to the monopole. Still further exacerbating the problem is the observed fact that allowable stress associated with compression is generally less than the yield point stress which is associated with allowable stress using tension as a design criterion. It is also noted that adding guys generally does not increase the structure's ability to accommodate compressive loading.
[0019] The steel used in monopoles is high strength steel. When the design of such monopoles is based on deflection, the steel is often stressed to less than seventy per cent of the yield point stress of the steel. Plate used for bent plate structures commonly has a yield point of sixty-five thousand pounds per square inch (psi). However, the allowable stress, when compression governs, is often about fifty-two thousand psi. Thus, if it is possible to retrofit an existing monopole that has been designed using limits associated with compression to actually be limited by tension instead, an additional percentage (in the case presented above, an additional twenty-five per cent) in design limits could be gained. Further, if mil tests for plates in a particular structure are available, it may be possible to determine that the yield point stress exceeds the minimum specified value thereby creating an opportunity to further increase the design limits associated with an existing monopole. As can be understood from the teaching of the above discussion, increasing the design limits of an existing monopole will permit that monopole to support additional antennas without requiring guys or the like or without requiring replacement of existing monopoles.
[0020] The present inventive entity has discovered that the design limits of an existing monopole can be increased by strengthening the monopole in its ability to accommodate compressive loading. This increase of strength in compression thus permits the design limits to be based on tension rather than compression. As discussed above, the allowable stress associated with compression is generally less than the yield point stress which would be the allowable stress if tension governs the design. This thus increases the load carrying capacity of a monopole.
[0021] Thus, the present invention overcomes the above-discussed problems and drawbacks by increasing the compression limits of an existing monopole by supporting the compression faces and by increasing its section modulus which allows more load-carrying capacity. One form of the invention achieves this goal by placing filler material that is strong in compression inside the monopole.
[0022] This takes advantage of the fact that most existing monopoles are hollow. By increasing the compression design limits of a monopole, expense and effort are directed to the most efficient use of resources and are not wasted on increasing design limits that are not as efficiently utilized for increasing compression limits.
[0023] Still further, increasing the compression limits of an existing monopole by filling the monopole with material that is strong in compression takes advantage of the fact that most existing monopoles are already hollow and the filler material can be installed in an economical manner. Still further, using the hollow nature of existing monopoles to add strengthening material internally to the monopole permits strengthening the monopole without endangering the aesthetics of such poles that have already been approved. Thus, the inventive means and method of the present invention is a way of increasing the design limits of an existing monopole in a manner that is both efficient and economical thereby increasing the strength of a monopole to accommodate additional antennas becomes economically feasible.
[0024] The present invention also includes strengthened base plates and foundations supporting monopoles.
Technical Field of the Invention
[0025] The present invention relates to the general art of static structures, and to the particular field of monopoles.
Objects and Advantages of the Invention
[0026] It is a main object of the present invention to provide a means for increasing over-the-air coverage while meeting the requirements placed on locating monopoles.
[0027] It is another object of the present invention to provide an apparatus and methods for increasing the number of antennas that can be supported on an existing monopole without requiring guy re-enforcement of the monopole.
[0028] It is another object of the present invention to strengthen an existing monopole without changing the aesthetics of the existing monopole.
[0029] It is another object of the present invention to strengthen an existing monopole by adding strengthening material internally of the monopole.
[0030] It is another object of the present invention to strengthen an existing monopole in the most efficient and cost effective manner.
[0031] It is another object of the present invention to provide a means and a method for modifying existing monopoles to accommodate additional antennas without requiring replacement of such existing monopoles.
[0032] It is a more specific object of the present invention to strengthen an existing monopole by increasing the design limit that is most effective in providing the overall increase in design limits that will be most effective and efficient to increase the load carrying capacity of the monopole.
[0033] Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
[0034] The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] [0035]FIG. 1 is an elevational view of one form of a monopole.
[0036] [0036]FIG. 2 is an elevational view of another form of a monopole.
[0037] [0037]FIG. 3 is a sketch that illustrates loading on a monopole subject to wind forces.
[0038] [0038]FIG. 4 is an elevational view of one form of a monopole that has been modified and strengthened according to the teaching of the present invention.
[0039] [0039]FIG. 5 is an elevational view of another form of a monopole that has been modified and strengthened according to the teaching of the present invention.
[0040] [0040]FIG. 6 is a top plan view of a base of a monopole.
[0041] [0041]FIG. 7 is an elevational view of a base of a monopole.
[0042] [0042]FIG. 8 is a top plan view of a template used in a base of a monopole.
[0043] [0043]FIG. 9 is a partial view of a multi-sided monopole which has been strengthened by affixing strengthening elements to the outside surface, or surfaces, of the monopole.
[0044] [0044]FIG. 10 is an enlarged view of a portion of the monopole shown in FIG. 9.
[0045] [0045]FIG. 11 is a cross-section of a twelve-sided pole.
[0046] [0046]FIG. 12 is an enlarged view of FIG. 10.
[0047] [0047]FIG. 13 is similar to FIG. 12 but with an access flange through which internal cables pass into a pole.
[0048] FIGS. 14 - 16 are similar to FIGS. 11 - 13 respectively, showing a monopole that is circular in perimetric shape.
DETAILED DESCRIPTION OF THE INVENTION
[0049] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
[0050] It is noted that the present disclosure will refer to antennas or antenna structures. It is intended that the term “antenna” will cover any element used in over-the-air communication systems, including microwave dishes, supporting platforms and the like and it is not intended to limit the scope of this invention to antennas per se. It is also intended that the broad term “over-the-air communication system” covers cellular telephone systems as well as any other such system.
[0051] Two types of existing monopoles are shown in FIGS. 1 and 2. Both monopoles are tubular and hollow and are formed of steel to have a hollow interior and are anchored at the base thereof in the ground. One type of existing monopole is unitary and is shown in FIG. 1 as monopole 10 . Monopole 10 has a base 12 that is cast in ground G and a base assembly 14 . Monopole 10 extends upward from ground G and tapers to a top area 15 . As indicated, monopole 10 supports a variety of elements that are associated with over-the-air communication systems, such as antennas 16 , dishes 18 and the like. These elements are positioned on monopole 10 at levels above the ground, indicated by level 20 which corresponds to the lowest level of the elements existing on the monopole. One form of existing monopole is one hundred fifty feet tall, has a fourteen inch top diameter and a sixty inch base diameter. Antennas are located at the one hundred fifty foot level and at the one hundred thirty foot level, with the one hundred thirty foot level being indicated as level 20 .
[0052] Monopole 10 is hollow as indicated by dotted lines 22 to define an inner bore 24 and has been designed to safely support the communications elements in position to effectively carry out the functions associated with such elements in over-the-air communications systems. Thus, design stresses, yield points, and the like have been selected to achieve this goal.
[0053] An alternative form of monopole 10 ′ is shown in FIG. 2 as including a plurality of sections, such as sections 30 and 32 , that have outside diameters differing from each other to produce a stepped shape with a shoulder 34 between adjacent sections. Otherwise, monopole 10 ′ is identical to monopole 10 and includes a hollow bore 24 ′ and supports elements such as an antenna dish 18 at a first level, with the lowest level element being at a level 20 above the ground. Other forms of monopoles may occur to those skilled in the art based on the disclosure herein and these additional types of monopoles are also intended to be included in the scope of this disclosure and invention.
[0054] For convenience, the elements on the monopoles as these monopoles exist prior to being modified according to the teaching of the present invention to support additional elements will be referred to as first elements. Elements added to the existing monopoles to accommodate additional traffic in over-the-air communications systems will be referred to as second elements.
[0055] Referring to FIG. 3, the various forces of interest to this disclosure are identified. Thus, the wall W of monopole M is subject to a force associated with the weight W t which manifests itself as a compressive force C on the wall of the hollow monopole. As the structure is exposed to wind D, the pole deflects in direction X from vertical. Due to this deflection, various portions of the monopole wall are subjected to forces. Thus, one portion T 1 of wall W is subject to tension T due to the deflection of the monopole, while another portion C 1 of wall W is subject to compression force C 2 . This compression force is added to the compression force C associated with the weight of the monopole and the elements supported thereon.
[0056] As discussed above, the inventive entity of the present invention has discovered that if the design of an existing monopole can be controlled by tension, there is additional bending capacity that can be utilized so more antennas can be installed on an existing monopole that has been thus modified. This is achieved by adding elements to the existing monopole that adds to the strength of the monopole in regard to compression.
[0057] Accordingly, the best mode of the present invention includes placing a filler element that is strong for compression forces inside the hollow bore of the existing monopole. Specifically, the best mode of the present invention includes placing expanding foam and aggregate, lightweight aggregate concrete normal aggregate concrete or the like in the bore of the hollow existing monopole. The concrete is the most efficient and economical element that can be used to achieve the purposes of this invention. One form of the aggregate used for this concrete is manufactured under the trademark HADITE. Other types of concrete, including that which uses standard weight aggregate, can also be used as will occur to those skilled in the art based on the teaching of the present disclosure. These additional types of fills and concrete are intended to be included in the scope of this invention as well.
[0058] Referring to FIGS. 4 and 5, it can be seen that monopole 10 is modified to monopole 10 R, or retrofit, by locating filler material 50 into the hollow bore 24 as by flowing the filler into the bore via a hole defined through the wall of the pole, or the like. The filler material is filled in the bore to a level 52 . While this level can vary according to the factors associated with each monopole, the best mode of the present invention includes level 52 being essentially co-level with the level of the lowest element of the first elements existing on the monopole before the monopole is modified to include the filler material. That is, level 52 is essentially co-level with level 20 .
[0059] Once filler material 50 is in place, additional elements, 16 ′ and/or 18 ′ can be added to the monopole. These additional, or second, elements can be located at levels that are lower than levels 20 and/or 52 because they are manufactured using technology that is newer than the technology used for first elements 16 and/or 18 . However, it may be possible to add antennas above the first elements.
[0060] Referring to FIG. 5, it is seen that monopole 10 ′ is modified, or retrofit, as monopole 10 ′R, by locating filler material 50 in bore 24 of monopole 10 ′ to level 52 ′ that is co-level with antennas 16 ′. Antennas 16 ′ are located at a level that is above level 20 ; however, this is illustrated to emphasize that the actual level of the filler material is dictated by the particular conditions associated with the particular monopole being modified. The level of the concrete will depend on the added antennas and the specific pole and any other appropriate design criteria as will be understood by those skilled in the art based on the teaching of this disclosure.
[0061] As will be understood by those skilled in the art based on the teaching of this disclosure, the steel monopole is not the only area of concern. Foundation structure 60 shown in FIGS. 6, 7 and 8 includes a central section 62 to which plates 64 and 66 are attached and on which anchor bolts 68 are mounted by nuts 70 . Central section 62 is pre-existing and is placed when the pre-existing monopole is erected. In order to accommodate the extra weight and forces associated with the modified monopole, foundation 60 is modified to include a collar 70 of concrete or the like to add further stability to the foundation structure. One form of the modified foundation includes an outside diameter of eighty-four inches and a thirty foot depth, with a collar 70 of twelve inches in width and a depth of seven and one-half inches.
[0062] The base plates can be replaced or stiffened to accommodate the added forces and anchor bolts can be replaced or added to accommodate the added forces as well.
[0063] If suitable, guys, such as guy 80 indicated in FIGS. 4 and 5, can be added. The guys can be colored or the like to accommodate aesthetic considerations. Additionally, seismic considerations can be addressed in a manner that is common to such considerations, as by adding material, or special elements that can accommodate seismic events.
[0064] Additionally, the filler material includes sufficient internal as well as external passages to accommodate water as from rain, snow, or the like. Additives can also be used to meet these considerations as well as to address shrinkage, adherence and the like as will be understood by those skilled in the art based on the teaching of this disclosure.
[0065] Design criteria can be implemented in a software program so filler height, filler density, foundation structure design, economics and the like can be analyzed before a monopole is modified.
[0066] It is noted that any coaxial communication cables that are located inside an existing monopole should be removed and either moved to the outside of the monopole or be replaced by new coaxial cables on the outside of the monopole before filler material is added.
[0067] It is noted that, in the embodiments disclosed hereinbelow, the strengthening of the monopole is achieved by affixing strengthening elements, such as plates, to the external surface, or surfaces, of the monopole; whereas, the strengthening of an existing monopole discussed above has been achieved by adding strengthening material internally of the monopole.
[0068] The foregoing discussion has been directed to a monopole which will be strengthened by adding filler material internally; however, some monopoles have one or more external surfaces that are amenable to accommodating strengthening elements. In fact, some monopoles can have as many as eight or twelve sides. The present invention takes advantage of this feature to increase the strength of an existing monopole. This approach is illustrated in FIGS. 9 - 13 in which a polygonal monopole 10 P is supported by an anchor assembly 60 P and has an antenna structure 16 P supported thereon. As discussed above, additional antenna structures 16 ′P are to be added for the reasons discussed above. In order to achieve this goal, monopole 10 P should be strengthened. This is achieved by fixing strengthening plates 100 to one or more faces of the polygonal monopole 10 P. In one form of the invention, plates 100 are affixed to each face of the polygonal monopole. As shown in FIG. 9, a bridge structure 102 is included to support cables as they enter the monopole. As those skilled in the art will understand based on the teaching of this disclosure, such a bridge structure can be used in connection with any of the monopoles disclosed herein.
[0069] As is best shown in FIG. 9, plates 100 are formed to conform to the shape of the faces on the monopole to which they are attached. Thus, as can be seen in FIG. 9, the plates taper outwardly near the bottom of the in-place plate. That is, the width of a base plate as measured between sides 104 and 106 near the bottom 108 of the plate is greater than the width of the plate near the top 110 of the plate.
[0070] As is best indicated in FIG. 12, one method of fixing the plates to the outer surface of the monopole wall is by adhesive 112 . The surface preparation required will be known to those skilled in the art based on the conditions and materials used in the monopole, the adhesive and the plates. For example, a monopole that is galvanized metal having steel plates fixed thereto will have one form of surface preparation while a painted monopole may have another form of surface preparation as well as another adhesive. A cable or band 114 can be used to encircle the plates mounted on the monopole and support those plates in position while adhesive 112 is setting up. Only a portion of the cable is shown for simplicity of illustration, but it is understood that the cable will encircle the plates and several cables can be used if necessary. The plates preferably are formed of steel, but other shapes and materials can also be used based on the requirements of a particular application. In one form of the plates, the plates are one-eighth inch thick but other thicknesses can be used without departing from the scope of the present invention.
[0071] As indicated in FIG. 13, one of the strengthening plates, plate 100 ′, can have a bore 122 defined therethrough to accommodate an access collar 124 . Cables, such as cable 126 extend into interior 128 of the monopole via collar 124 . Collar 124 can be located in conjunction with bridge 102 if desired and suitable.
[0072] As discussed above, the strengthening plates can extend from adjacent to the ground in which the monopole is supported to adjacent to the level of the lowest antenna structure to be added. Thus, as illustrated in FIG. 9, a future antenna structure 16 ′P will be added beneath the lowest level of existing antenna structures 16 P. However, it may be possible to add antennas above the first elements. The level of the lowest existing antenna structure 16 P is indicated at 20 ′ and the level and the level of the highest proposed antenna structure is indicated as 20 P. Strengthening plates 100 are fixed to the monopole to adjacent to level 20 P. That is, for example, the length of each plate 100 in the installed condition as measured from top end 100 T to bottom end 10 B, is essentially equal to, but can be slightly less than, distance 20 P. A bottom plate 130 can encircle the bottom of the monopole if desired. The level of the top of the strengthening elements will depend on the added antennas and the specific pole and any other appropriate design criteria as will be understood by those skilled in the art based on the teaching of this disclosure.
[0073] The technique in which strengthening plates are fixed to the outer surface of a wall of a monopole can be used to strengthen a monopole having a circular outer perimetric shape as well. This provides an option for strengthening a circular monopole that is in addition to the method discussed above in which concrete is placed in the hollow bore of the monopole. This second option is illustrated in FIGS. 14 - 16 . Strengthening plates 100 C are fixed to outer surface 140 of circular monopole 10 C using suitable fixing means 142 to strengthen monopole 10 C in the manner discussed hereinabove. Plates 100 C can be steel and the fixing means can be any of the above-discussed means. Thus, suitable adhesive, or chemical bonds, or metallurgical bonds or the like can be used depending on the conditions and requirements. Plates 100 C can also taper if necessary to match the shape of the existing monopole to be strengthened as discussed above with regard to monopole 10 P shown in FIG. 9. A cable or band 114 ′ or a plurality of cables and/or bands, can also be used to secure the plates in place while the bonds between the plates and the monopole are formed and set up. The cable or band is shown spaced from the plates in FIGS. 12 and 14, but will contact those plates as necessary to hold them in place during the formation of the bond between the plates and the monopole.
[0074] As discussed above, plates 100 C will extend from adjacent to the ground supporting a monopole to be strengthened, to a level adjacent to the level of the highest added antenna structure. As the case with the foregoing forms of the invention, antenna structures can be added to the monopole at levels below the level of the highest added strengthening structure. Such antenna structures will be mounted on the strengthening plates in the embodiments using strengthening plates fixed to the outer surface of the monopole. Alternatively, the level of the top ends of the plates added in either monopole 10 P or 10 C can be essentially equal to the level of the lowest existing antenna structure, such as level 20 ′ in FIG. 9. Also, the top end of internally added strengthening material in the forms of the monopole discussed in relation to FIGS. 4 and 5 can reach the level of the lowest level existing antenna structure, such as level 20 in FIGS. 1 and 2. The level of the strengthening elements in this embodiment,like that of the other embodiments, will depend on the added antennas and the specific pole and any other appropriate design criteria as will be understood by those skilled in the art based on the teaching of this disclosure.
[0075] As is the case with the polygonal monopole, one of the plates fixed to a circular monopole, plate 100 ′C can have a bore 122 ′ defined therethrough to accommodate a collar 124 ′ through which cables 126 extend into bore 128 C of monopole 10 C having a circular perimeter.
[0076] It is also noted that the external strengthening that has been discussed hereinabove can be used in conjunction with the internal strengthening discussed in association with FIGS. 4 and 5. That is, strengthening material 50 can be located inside a monopole, and strengthening plates, such as plates 100 and/or 100 C can be applied to the outside of the monopole as well, depending on whether the monopole is circular or polygonal in outer perimetric shape. Thus, in appropriate circumstances, a monopole can be strengthened both internally and externally. This is indicated in FIGS. 4 and 5. While only one strengthening element is shown on each monopole, it is understood that as many as necessary can be used, and the showing of only one strengthening element is merely for the ease of illustration and is not intended to be limiting.
[0077] It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown. | An existing monopole is strengthened to accommodate loading associated with additional elements included in over-the-air communications systems by fixing strengthening elements to the exterior surface of the monopole. Monopole strengthening may require base plate strengthening, adding anchor bolts and/or foundation strengthening. This permits an existing monopole to accommodate more elements than were initially envisioned when the monopole was initially erected. | 4 |
This is a continuation of application Ser. No. 08/205,090 filed on Mar. 3, 1994, now U.S. Pat. No. 5,423,003.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to a system for managing distributed information system applications, such as networked computer applications, in which an application manager computer interfaces logically to a service control point of a telecommunications network.
2. Background and Description of the Prior Art
The Telecommunications Infrastructure:
The global telecommunications infrastructure is evolving into an "Advanced Intelligent Network" (AIN). Such a network will be much more than a matrix of switches to provide end to end connection. The network will provide network management functions, computer data translation from one computer protocol to another, and many other enhanced services.
Three characteristics of the telecommunications network infrastructure which are significant developments for data networks are:
a. the deployment of packet switching systems for data movement,
b. The implementation of a separate signalling network using data packets, and
c. The incorporation of computer databases into the signalling network for network control functions, such as routing phone calls.
An important characteristic of the modern telecommunications infrastructure is the use of "out-of-band" signalling as described in the industry standard, Common Channel Signalling System Number 7 (CCSS7 or just SS7). Instead of using a portion of the bandwidth of a communication channel for signalling (e.g. dialing a phone number), the signalling information (e.g. dialed digits) is sent over a separate channel (part of a signalling network) as "packets" of digital information. These packets are processed by computer systems which are part of the telecommunications network infrastructure. For example, to make a call, the calling party causes a "call-setup packet" to be transmitted to a computer which is part of the SS7 network structure. This computer, using a database of information and the signalling network, determines whether the connection can be made to the called party and, if so, causes the end-to-end communication line to be established.
Another important characteristic of the modern telecommunications infrastructure is the provision of "bandwidth-on-demand". For example, using Integrated Services Digital Network (ISDN) services, multiple individual communications channels may be combined to provide one high speed communications channel and then the high speed channel may be separated back into multiple individual communications channels again. Thus, the "bandwidth-on-demand" provides the additional data transmission capacity only for the duration of time when needed.
Distributed Information System Applications:
Meanwhile, the computer industry is evolving into a network of computers, large and small, which need to constantly exchange information and share resources. These networks of computers are often distributed over many locations, encompassing a large geographical area, even including worldwide network interconnection.
An application is defined as a "distributed application" if it is distributed over two or more computer sites connected by a communication network and if it has both a "global application" and autonomous local applications operating independently at two or more of the individual sites. A global application is one which requires accessing data at more than one site.
In the prior art, the coordination and management of global applications over such networks is done by computers which are logically "outside of" the telecommunications network infrastructure, that is the computers which are programmed to coordinate and manage the global applications are not closely integrated into the telecommunications network. This lack of close integration of global applications and the telecommunications network results in a system architecture which is not cost effective because it does not take maximum advantage of telecommunications network resources to minimize the cost of information movement. A need therefore exists for the coordination and management functions of distributed information system applications to be closely integrated into the telecommunications network in order to minimize the cost of information movement across the telecommunication network. Additionally, such close integration would facilitate more robust alternate routing procedures to enable more reliable interconnection management.
SUMMARY OF THE INVENTION
An object of this invention is to provide more effective and efficient management of the interconnection and data exchange in a distributed information system application through the use of the more robust network access, management and control capabilities of the Common Channel Signalling System Number 7.
Another object of this invention is to make use of the present and future capabilities of CCSS7 for call control, remote control, network database access and management and maintenance to provide more reliable interconnection management of distributed information system applications.
A further object of this invention is to make use of such present and future capabilities of CCSS7 to accomplish more cost effective movement of information between the networked computer systems.
In summary, the present invention is a system for managing a distributed information system application which integrates an application manager device for each global application into the telecommunications network, thereby providing a solution to the need for coordination and management of networked computer applications. The application manager device may be a computer system with specific hardware, software, and interfaces or may be special software added to the telecommunications network computers, depending upon the application.
The telecommunications network is adapted to include an interface for the application manager which provides access to the network for issuing queries, commands and messages for coordination and control of the network connections and application processes. The telecommunications network is further adapted to route certain transactions to the application manager for processing.
In the preferred embodiment of the present invention, the application manager computer system is logically connected through the interface directly to an SS7 service control point. This arrangement enables the application manager computer to communicate directly with the service control point and command it to interconnect the various information storage, retrieval and/or management devices, such as computers, in the distributed information system application in the most efficient manner, both from speed and connection standpoints. To accomplish this, the application manager computer is programmed with information for each application concerning the location and database content of each computer or information management device in the application, and the speed, types and alternate routing information for the communication links which are available for connecting the various computers in the application. With this information, the application manager computer determines the most efficient connection scheme for the particular networked application and instructs the service control point directly to make the necessary connections.
This system design provides for more cost effective management of the movement of information across the network by enabling effective use of "bandwidth-on-demand" and by eliminating unnecessary connections. The system design enables more reliable interconnection management because the application can include alternate routing algorithms. This system design would be employed to satisfy the needs of a wide range of information applications, such as database management, process monitoring and control, information services management, reservations system management, publishing, and distribution systems for movies, video, or audio.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and additional objects, features and advantages of the present invention will become apparent from the following detailed description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings in which:
FIG. 1 is a block diagram of the system architecture for a telecommunications system constructed in accordance with the preferred embodiment of the present invention;
FIG. 2 is a graphical illustration of the software programs executed by the application; and,
FIG. 3 is a block diagram of an example of how the system of FIG. 1 can be employed to manage a networked computer application.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to a more detailed consideration of a preferred embodiment of the present invention, FIG. 1 shows a block diagram of the system architecture for a telecommunications system adapted for the invention. The telecommunications network architecture is composed of a number of conventional switching and process nodes 10, which as illustrated include packet switches, central office switches and tandem switches. All of the nodes 10 are interconnected by a network of transmission links 12 and a conventional SS7 signalling network 13 is employed to control these interconnections. The SS7 signalling network 13 includes a plurality of signalling links 14 and a plurality of service control points 16 and 17. The signalling links 14 connect each of the switching nodes 10 to one of the service control points 16 or 17, as well as the service control points 16 and 17 to each other.
The service control points 16 and 17 are computer based elements which perform the usual SS7 network control functions. For telephone calls where the called party is located on a node outside of the node where the calling party is located, or where special calling codes, such as 800 or 900 calls, are used, service control points are used to determine and establish the routing between the endpoints. Each service control point has a computer system including a database containing the information necessary to determine the transmission links which can provide a path between the two parties. The determining and establishing of transmission links between the calling and called parties is accomplished by signalling messages sent between the switch nodes and service control points and between service control points. A detailed description of the SS7 signalling protocols and message formats is given in standards documents published by the Consultative Committee on International Telephone and Telegraphy (CCITT) and by the American National Standards Institute.
A very important element of the system architecture of the present invention is the attachment of an application manager device, such as a computer 20 and associated application database 21 to the service control point 16, using a communications interface 18; making the application manager computer 20 logically attached directly to the computer system in the service control point 16. The application manager program software is thereby integrated with the SS7 network control software programs to provide the capability for the exchange of queries, messages and commands necessary to establish interconnection of network transmission links. The preferred embodiment of the interface 18 is an ISDN interface and special switch node software with ISDN to SS7 interworking which provides a logical connection to the service control point 16 and full access to all SS7 networking capabilities. The particular configuration of the interface 18 depends of course on the configuration of the telecommunications network to which it is connected. Fundamentally, however, the interface 18 is like any other conventional interface for connecting two communications devices. These interfaces are already being implemented to allow open access to third parties to the Advanced Intelligent Network now being implemented by the telecommunications industry. An example of such an interface is described in the FCC Supplementary Comments filing by BellSouth dated Jul. 7, 1993 under CC Docket No. 91-346.
Alternatively, the interface 18, application manager computer 20 and application database 21 can be an integral part of the computer system and associated software in the service control point 16. In this case, the interface 18 is actually a software interface contained within the control point's software, and the application manager computer 20 is a separate software module in the service control point computer system.
The application manager computer 20 therefore receives and transmits messages related to the networked computer application through the service control point 16. These messages allow the application manager computer 20, in conjunction with the inherent capabilities of the service control point 16, to establish network interconnections between a plurality of distributed information storage, retrieval and/or management devices, such as application computers 22, that are each connected to separate ones of the switching nodes 10 in the telecommunications network. The application manager computer 20 also sends queries and commands through the service control point 16 to each of the application computers 22 to control the application processes. In this manner, the telecommunications network, through the service control point 16, identifies messages which are addressed to the application manager computer 20 and executes signalling commands issued by the application manager computer 20.
The application manager database 21 contains data structures and data elements from the following sets:
a. data elements, data structures and data directories which are part of the application;
b. a master data directory containing the information which describe the distribution of the database structure and elements; and,
c. a routing directory containing the information which describes location and path information for each of the distributed database locations.
The application manager computer 20 distributes data updates and responds to information requests, directing the movement of data to effect the updates and responses. It also selectively invokes program processes in the application computers 22 to coordinate and control the application. Two groups of software elements included in the application manager provide the capability to coordinate and control the application. These software elements are the programs and data related to the application processes and data structures, and the programs and data related to the telecommunications network signalling procedures and routing paths.
Referring to FIG. 2, the application manager computer 20 executes software programs which include a main program 200 for coordination and control of the networked application, process routines 210 related to the application, network signalling routines 220 and telecommunications network software interface routines 230.
The main program 200 implements the primary functions of managing queries and managing update transactions. The process routines 210 include the software program modules which implement algorithms for optimization of the query processing, including selection of the assembly site and determination of the data transmission speed of each network connection used to move data from one network node to another. The network signalling routines 220 include the software program modules which construct, send, receive, and interpret messages to and from the telecommunications network. The telecommunications network software routines 230 include the software program modules which include the device driver for the specific network interface 18 permitted by the network owner, and which adapt the format of the messages to the format and protocol of the specific network interface 18.
The application data base 21 contains datastructures including master directories 300 for processes and data, datasets which include network routing data 310, and access rules and privileges data 330. For certain applications, the application database may also include process data and descriptors 320. Although FIG. 2 shows the application database 21 as a physical data storage device directly attached to the application manager computer 20, the database may be any suitable data storage media which is logically connected to the application manager computer 20.
The master directories for processes include tables of data describing the processes located at each node, while the master directories for data include tables of data describing the data elements located at each node. Network routing data tables include data from which the distance, costs, and available speeds of connections between nodes may be computed. Process data and descriptors includes the data necessary to describe physical processes which may be part of the application. Finally, access rules and privileges data tables provide the data which the application manager software programs use to determine whether a particular query from a particular user will be processed or access will be denied.
An example of an application which could advantageously be designed with the above system architecture principles would be a distributed database application for a business enterprise consisting of a network of database computers. FIG. 3 describes such an application.
For purposes of illustration, FIG. 3 includes two corporate headquarters computer facilities 500, 520, two regional office computer facilities 600, 620, and two local branch office facilities 700, 720. The two corporate computers, 500 and 520, are located in Los Angeles and New York, respectively, and the first regional computer 600 is located in Chicago. These three all have 64K BPS (64,000 bits per second) and 384K BPS, as well as "low speed" 4,800 BPS and 9600 BPS, data transmission capability. The second regional computer 620 is located in Atlanta and has 64K BPS capability. The local computers 700 and 720 are located in New Orleans and St. Louis, respectively, and have 4,800 and 9,600 bits per second capability, respectively.
The application manager computer 20 has been interfaced to the telecommunications network. As discussed previously in conjunction with FIGS. 1 and 2, the application manager computer 20 can, through use of the inherent capabilities of the signal control point 16, receive messages, send network interconnection messages, queries and commands, and can send messages and commands to the application computers 500, 520, 600, 620, 700, 720.
The "file allocation problems" of how to allocate data elements among the distributed database sites is not a part of the present invention. Much is known in the art concerning data allocation in distributed databases, and it is assumed in this example that the distributed database design has properly included data allocation considerations.
In the operation of the example illustrated in FIG. 3, an end user at the local computer site 700 enters a query which requires data elements from different computer sites for the query response to be satisfied. The language used to construct queries is not a part of the present invention. For ease of understanding by persons not trained in the art of database query programming, the example query is given in simple English language: "Print a list of all sales orders, including the order number, amount, and ship date, where the order total amount exceeded $100,000.00 and ship data was in year 1992 and the order included product number B4010BR, and the sales person was employee number 10132."
The local computer transmits the query as a network message whose destination is identified by the network as the application manager computer 20. That message, containing the query, is delivered over the network through the signal control point 16 to the application manager computer 20, which verifies that the end user has security privileges for the query and that the query answer can be constructed within the constraints of the application. If the verification produces a negative result, the appropriate response message denying the query is sent by the application computer 20 to the local computer 700 for delivery to the end user who entered the query. In that case no transmission link connections are made, saving unnecessary network usage.
If the verification produces a positive result, then the process continues as follows. The application manager computer 20 determines that the data elements required to satisfy the query response are distributed between the local computer 720 site, the corporate computer 520 site and the regional computer 620 site. In this example, the data elements giving the order total amount are located at the corporate computer 520 site, the data elements relating to the product number B4010BR and ship date are located at the regional computer 620 site, and the data elements relating to salesperson number 10132 are located at the local computer 720 site.
The application manager computer 20 maps the query into a form, called an envelope, that specifies a superset of the database that contains the data necessary to answer the original query. The application manager computer 20 translates the envelope into a reducer which consists of semijoin operations which can be executed in parallel at the three computer 520, 620, 720 sites, using an algorithm designed to minimize the cost of intersite data movement, and determining the site at which the data resulting from the reduction operations would be assembled. The result, of course, also reduces the use of network resources, making more efficient use of the network.
The application manager computer 20 sends messages which contain each of the three reduction operations to the respective computer 520, 620, 720 sites for parallel execution. After the reduction operations are completed, each of the three application computers 520, 620, 720 sends a notice of completion message to the application manager computer 20. The techniques used by the application manager to determine where all of the data elements are located and to determine the assembly site, as well as algorithms to compute the reduction operations, are well known in the art. One such implementation of these techniques is illustrated in the publication, "Query Processing in a System for Distributed Databases (SDD-1)" by Philip A. Bernstein et al., ACM Transactions on Database Systems, December 1981. For the example query, the assembly site is the regional computer 620 site.
The network control signalling messages sent by the application manager computer 20 result in corporate computer 520 being connected to regional computer 620, using a 384K BPS connection, and local computer 720 being connected to regional computer 620, using a 9,600 BPS connection. The application manager computer 20 then sends messages to computers 520, 620, 720 indicating connections have been made and requesting transmission of the data resulting from the reduction operations to the assembly site, regional computer 620. The data from corporate computer 520 is transmitted to regional computer 620 and the data from local computer 720 is transmitted to regional computer 620. When the data transmissions are completed, regional computer 620 sends a completion acknowledgement message to the application manager computer 20. The application manager computer 20 sends network control signalling messages which cause the connections between corporate computer 520 and regional computer 620 and between local computer 720 and regional computer 620 to be disconnected.
The application manager computer 20 sends a message to regional computer 620 requesting regional computer 620 to execute the query, using the superset of the database assembled at regional computer 620. Regional computer 620 executes the query and sends a message to the application manager computer 20 confirming that the query answer is computed.
The application manager computer 20 sends network control signalling messages which cause local computer 700 to be connected to regional computer 620, using a 4,800 BPS connection, and then sends a message to regional computer 620 requesting that the query answer be transmitted to local computer 700, where the query originated. The query answer is made available to the end user who entered the query. Local computer 700 sends a message to the application computer 20 confirming that the query answer has been received. The application manager computer 20 then sends network control signalling messages which cause the connection between local computer 20 and regional computer 620 to be disconnected. Processing of the query is completed.
It will be understood that the foregoing example represents only one possible use of the present invention and that the invention can be applied to any distributed information system application requiring interaction between or among a plurality of remotely located information storage, processing and communication devices. The specific applications of the invention are numerous and include database information services, process control for chemical and mechanical processes, management of the storage, retrieval and transmission of documents, educational instructions, video images (i.e. video tapes), audio messages and music, credit card transaction processing, software distribution, retail store management, shipment and vehicle tracking, reservations, ticket sales and many others.
In summary, the present invention provides a system for managing networked, distributed information systems which greatly increases the efficiency with which information is communicated among or between a plurality of remotely located information storage, processing and management devices, such as computers. The system takes advantage of the capabilities of an Advanced Intelligent Network, such as SS7, by interfacing directly to a service control point of the network. This provides the application manager computer with the ability to configure the network in the most efficient manner to handle the information transfer needs for the particular application.
Although the invention has been disclosed in terms of a preferred embodiment and variations thereof, it will be understood that numerous other variations and modifications could be made thereto without departing from the scope of the invention as defined in the following claims. | A system for managing distributed information system applications employs an Advanced Intelligent Network (AIN) telecommunications network based upon the industry standard, Signalling System 7 (SS7). SS7 employs intelligent, computer based service control points which cause interconnections to be made among switching nodes in the network to facilitate communications between the various nodes. In the system of the present invention, a plurality of information storage, retrieval and/or management devices, such as applications computers, are selectively interconnected with one another via the telecommunications network. In order to more efficiently manage these interconnections, an applications manager computer is interfaced to one of the service control points and controls which interconnections are to be made by the service control point. The applications manager computer employs data on the particular application, routing algorithms and transmission link speed data to determine the best scheme for interconnecting the applications computers and then instructs the service control point to make the necessary connections and transmit the necessary commands to implement the particular application. The system has a wide range of information applications, such as database management, process monitoring and control, information services management, reservations system management, publishing and distribution systems for movies, video or audio. | 7 |
FIELD
[0001] The present described embodiments relate to a snowboard binding and a snowboard.
BACKGROUND
[0002] A snowboard binding is used in order to bind the snowboard rider's boot to the snowboard. In some snowboard bindings, to hold the rider's boot to the snowboard binding, an ankle cap assembly and a toe cap assembly are provided. The ankle cap assembly and the toe cap assembly each include two straps that are releasably connected to one another by a ratchet mechanism fixed to one of the straps. The ratchet mechanism engages with the other strap, called a ladder strap, which includes ladder-type teeth thereon that function with the ratchet mechanism to permit adjustment of the connection pressure of the respective ankle cap assembly and the toe cap assembly by actuating the ratchet mechanism back and forth.
[0003] Strapping into current binding technology can be difficult. The user is required to step through and around the straps, or use their hands to move aside the straps just to get a boot into the base or frame of the binding. Depending on the user's snowboarding skill level, this part of the process could force a beginner to have to sit down on a bench or directly on the snow in order to maneuver their boot into the binding. Once the boot is positioned in the binding, the user then has to use both hands to feed the ladder strap through the ratchet mechanism, which could be full of snow and/or ice, and then the user actuates the ratchet mechanism to tighten the straps with hopes of achieving correct tightness. If the straps are too loose, the user's boot slides around inside of the binding frame; if the straps are too tight, circulation to the user's feet can be cut off. These problems are increased by the fact that a user is required to disconnect one boot from a binding each time when riding a chairlift to the top of the mountain (or disconnecting both boots when riding a gondola) so that the user must reconnect their boot to the binding each time after exiting the chairlift.
SUMMARY
[0004] A snowboard binding and a snowboard that incorporates a pair of the snowboard bindings are described. The snowboard binding eliminates the ratchet-type connection used in conventional snowboard bindings. Instead, the snowboard binding incorporates a connection mechanism that is somewhat similar to a ski-boot style connector, and that uses only two straps on each binding compared to the traditional four straps. In addition, the connection mechanism can be pre-adjusted by the user to the desired connection pressure. Once the desired pre-adjustment is reached, the user can simply step into the binding and connect the connection mechanism without needing to adjust the connection pressure or tightness during mounting of the user's foot or boot to the board as is required with conventional snowboard bindings.
[0005] In accordance with one described embodiment, a snowboard binding is provided that includes a binding frame; an ankle cap connected to the binding frame; a first buckle attached to the ankle cap; a first engagement member connected to the first buckle; a first binding hook directly attached to the binding frame and releasably engageable with the first engagement member; a toe cap connected to the binding frame; a second buckle attached to the toe cap; a second engagement member connected to the second buckle; and a second binding hook directly attached to the binding frame and releasably engageable with the second engagement member.
[0006] In accordance with another described embodiment, a snowboard binding is provided that includes a binding frame; an ankle cap connected to the binding frame; an ankle cap strap attached to the binding frame and to the ankle cap; and an ankle cap buckle mechanism connecting the ankle cap and the binding frame. The ankle cap buckle mechanism includes a first buckle, a first engagement member, and a first binding hook. The first buckle and the first engagement member are mounted on the ankle cap, and the first binding hook is mounted on the binding frame and is releasably engageable with the first engagement member. The binding also includes a toe cap connected to the binding frame; a toe cap strap attached to the binding frame and to the toe cap; and a toe cap buckle mechanism connecting the ankle cap and the binding frame. The toe cap buckle mechanism includes a second buckle, a second engagement member, and a second binding hook. The second buckle and the second engagement member are mounted on the toe cap, and the second binding hook is mounted on the binding frame and is releasably engageable with the second engagement member.
[0007] In accordance with still another described embodiment, a snowboard binding is provided that includes a binding frame means; an ankle cap assembly that includes an ankle cap means connected to the binding frame means, a first buckle means attached to the ankle cap means, a first engagement means connected to the first buckle means, and a first binding hook means that is releasably engageable with the first engagement means. The first binding hook means is mounted directly on an outwardly facing side surface of the binding frame means. The binding also includes a toe cap assembly that includes a toe cap means connected to the binding frame means, a second buckle means attached to the toe cap means, a second engagement means connected to the second buckle means, and a second binding hook means that is releasably engageable with the second engagement means. The second binding hook means is mounted directly on the outwardly facing surface of the binding frame means.
[0008] In accordance with another described embodiment, a snowboard is provided. The snowboard comprises: two of the snowboard bindings described herein and a snowboard body. The snowboard body comprises an upper surface and a lower surface. The upper surface and the lower surface are opposite each other. The snowboard bindings are attached to the upper surface.
DRAWINGS
[0009] FIG. 1 is a perspective view of a snowboard according to one embodiment.
[0010] FIG. 2 is a front perspective view showing one of the snowboard bindings shown in FIG. 1 .
[0011] FIG. 3 is an enlarged perspective view of the region III in FIG. 2 .
[0012] FIG. 4 is an enlarged perspective view of the region IV in FIG. 2 .
[0013] FIG. 5 is another front perspective view showing the snowboard binding shown in FIG. 2 .
[0014] FIG. 6 is a left side view showing the snowboard binding shown in FIG. 2 .
[0015] FIG. 7 is a right side view showing the snowboard binding shown in FIG. 2 (illustration of several parts omitted).
[0016] FIG. 8 is a left side view showing the snowboard binding shown in FIG. 7 .
[0017] FIG. 9 is a top view showing the snowboard binding shown in FIG. 7 .
[0018] FIG. 10 is a bottom view showing the snowboard binding shown in FIG. 7 .
[0019] FIG. 11 is a front view showing the snowboard binding shown in FIG. 7 .
[0020] FIG. 12 is a rear view showing the snowboard binding shown in FIG. 7 .
[0021] FIG. 13 is a rear perspective view showing a first stage of connection of the snowboard binding according to one embodiment.
[0022] FIG. 14 is a rear perspective view showing a second stage of connection of the snowboard binding according to one embodiment.
[0023] FIG. 15 is a front perspective view showing a snowboard binding according to another embodiment.
DETAILED DESCRIPTION
[0024] FIG. 1 is a perspective view of a snowboard according to one embodiment. As shown in FIG. 1 , the snowboard A 1 comprises two snowboard bindings B 1 and a snowboard body B 2 . Each snowboard binding B 1 is attached to the snowboard body B 2 . Each snowboard binding B 1 is for binding a snowboard rider's boots (not shown) to the snowboard body B 2 .
[0025] FIG. 2 is a front perspective view showing one of the snowboard bindings B 1 shown in FIG. 1 . FIG. 3 is an enlarged perspective view of the region III in FIG. 2 . FIG. 4 is an enlarged perspective view of the region IV in FIG. 2 . FIG. 5 is another front perspective view showing the snowboard binding shown in FIG. 2 . FIG. 6 is a left side view showing the snowboard binding shown in FIG. 2 .
[0026] As shown in these figures, each snowboard binding B 1 includes a binding frame 1 (also referred to as a binding frame means), a highback 2 (which can be considered part of the binding frame 1 ), a base plate 3 , an ankle cap assembly 40 with an ankle cap 41 (also referred to as an ankle cap means), an ankle cap buckle mechanism 42 , an ankle cap strap 43 , a toe cap assembly 50 with a toe cap 51 (also referred to as a toe cap means), a toe cap buckle mechanism 52 , a toe cap strap 53 , and attaching members 7 A, 7 B.
[0027] FIG. 7 is a right side view showing the snowboard binding shown in FIG. 2 . FIG. 8 is a left side view showing the snowboard binding shown in FIG. 7 . FIG. 9 is a top view showing the snowboard binding shown in FIG. 7 . FIG. 10 is a bottom view showing the snowboard binding shown in FIG. 7 . FIG. 11 is a front view showing the snowboard binding shown in FIG. 7 . FIG. 12 is a rear view showing the snowboard binding shown in FIG. 7 . In these figures, illustration of the ankle cap 41 , parts of the ankle cap buckle mechanism 42 , the ankle cap strap 43 , the toe cap 51 , parts of the toe cap buckle mechanism 52 , and the toe cap strap 53 are omitted.
[0028] As shown in FIG. 1 , the binding frame 1 is attached to the snowboard body B 2 . The binding frame 1 can be made of, but not limited to, metal or plastic. As shown in FIGS. 2, 5, 6 , and 9 , the binding frame 1 includes a first outwardly facing side surface 11 and a second outwardly facing side surface 12 . The side surfaces 11 , 12 face in opposite directions. As shown in FIG. 9 , the first side surface 11 and the second side surface 12 face outwardly when the binding B 1 is viewed in a top view. As shown in FIGS. 2, 5, and 6 , the binding frame 1 also includes upper edges 15 . In the illustrated embodiment, one of the upper edges 15 is located at the upper end of the first side surface 11 , and another of the upper edges 15 is located at the upper end of the first side surface 12 .
[0029] With reference to FIGS. 2, 5, and 6 , the highback 2 is pivotally attached to the binding frame 1 by the attaching members 7 A, 7 B. Examples of suitable attaching members 7 A, 7 B can include, but are not limited to, screws, bolts, or the like. The highback 2 is foldable relative to the binding frame 1 between an upright position (shown in the figures) and a folded position (not shown) as in conventional snowboard bindings. When the highback 2 is in the upright position, the highback 2 comes into contact with the rear part of the snowboard rider's boot when the snowboard A 1 is used. The highback 2 can be made of, but not limited to, metal or plastic.
[0030] As shown in FIGS. 2, and 5 , the base plate 3 is attached to the binding frame 1 , and the base plate 3 is attached to the snowboard body B 2 for mounting the bindings B 1 to the snowboard body B 2 . In addition, the base plate 3 helps to keep the sides of the frame 1 spaced apart, and supports the snowboard rider's boots when the snowboard A 1 is used. The base plate 3 can be made of, but not limited to, metal or plastic. In the illustrated example, the base plate 3 includes two parts separated each other. Each of these parts is attached to the binding frame 1 by attaching members 7 C. The attaching members 7 C can be, but are not limited to, screws, bolts, or the like.
[0031] With reference to FIGS. 2, 3, 5, and 6 , the ankle cap 41 is connected to the binding frame 1 . The ankle cap 41 helps to hold the snowboard rider's boot to the binding frame 1 . The ankle cap 41 includes a first end portion 41 a and a second end portion 41 b. In the illustrated embodiment, the first end portion 41 a is disposed at one end of the ankle cap 41 in a width direction of the binding frame 1 . The second end portion 41 b is disposed at the other end of the ankle cap 41 in the width direction.
[0032] The ankle cap buckle mechanism 42 connects the ankle cap 41 to one side of the binding frame 1 . In the illustrated example, the ankle cap buckle mechanism 42 is attached to the first end portion 41 a of the ankle cap 41 , and is releasably attachable to the first side surface 11 of the binding frame 1 . The ankle cap buckle mechanism 42 can have two primary conditions—a connected condition and a disconnected condition. When the ankle cap buckle mechanism 42 is in the connected condition, the ankle cap 41 and the binding frame 1 are connected by the ankle cap buckle mechanism 42 (see FIGS. 2, 5, and 6 ). On the other hand, when the ankle cap buckle mechanism 42 is in the disconnected condition, the ankle cap 41 and the binding frame 1 are not connected by the ankle cap buckle mechanism 42 (see FIG. 14 ).
[0033] As shown in FIGS. 2, 5, and 6 , the ankle cap buckle mechanism 42 includes a first buckle 421 (also referred to as a first buckle means), a first engagement member 424 (also referred to as a first engagement means), and a first binding hook 426 (also referred to as a first engagement means).
[0034] The first buckle 421 is attached to the ankle cap 41 . Specifically, the first buckle 421 is attached to the first end portion 41 a of the ankle cap 41 . The first buckle 421 can be made of metal, plastic, or other suitable material. The first buckle 421 includes a support base 421 a, a lever 421 c, and a traction element 421 e.
[0035] As shown in FIGS. 3, and 6 , the support base 421 a is attached to the first end portion 41 a of the ankle cap 41 . The lever 421 c is pivotally attached to the support base 421 a through a pin 421 g. The traction element 421 e is pivotally attached to the lever 421 c through a pin 421 h. In the illustrated example, the traction element 421 e includes a rod 421 m and a housing 421 n. The rod 421 m of the traction element 421 e can be rotated into and out of the housing 421 n to adjust the length of the traction element 421 e. Thus, the connection tightness of the ankle cap assembly 40 (and the toe cap assembly 50 ) can be adjusted by adjusting the length of the traction element 421 e. In some embodiments, the rod 421 m of the traction element 421 e may not be adjustable. The buckle mechanism 42 (and the toe cap buckle mechanism 52 ) is generally similar in construction and operation to buckle mechanisms used on conventional ski boots except for the binding hook 426 .
[0036] The first engagement member 424 is connected to the first buckle 421 . Specifically, the first engagement member 424 is pivotally connected to the traction element 421 e of the first buckle 421 through a pin 428 . The first engagement member 424 can be made of metal, plastic or other suitable material. The first engagement member 424 has an opening 424 a. Though FIG. 6 shows an example in which the opening 424 a is rectangular, the shape of the opening 424 a is not limited to rectangular. The first engagement member 424 includes an engagement portion 424 c , for example a pin or bar, that is engageable with the first binding hook 426 . The engagement portion 424 c defines a part of the opening 424 a.
[0037] The first binding hook 426 is attached on the binding frame 1 . In this embodiment, the first binding hook 426 is non-rotatably attached to the binding frame 1 by the attaching member 7 A at a location to be engageable with the first engagement member 424 . The first binding hook 426 can be made of metal, plastic or other suitable material.
[0038] As shown in FIG. 6 , the first binding hook 426 includes a first base part 426 a and a first receiving part 426 c. The first base part 426 a is attached to the binding frame 1 by the attaching member 7 A. The first base part 426 a directly contacts the first side surface 11 of the binding frame 1 . The first receiving part 426 c is integrally formed on the first base part 426 a. The first receiving part 426 c receives a part of the first engagement member 424 (specifically, the engagement portion 424 c ), when the first binding hook 426 is engaged with the first engagement member 424 . The first receiving part 426 c directly contacts the engagement portion 424 c of the first engagement member 424 when the first binding hook 426 is engaged with the first engagement member 424 . The first receiving part 426 c is disposed in the opening 424 a of the first engagement member 424 when the first binding hook 426 is engaged with the first engagement member 424 . As shown in FIG. 6 , the first receiving part 426 c overlaps the binding frame 1 in a side view. The first receiving part 426 c includes a portion located below the upper edge 15 . In the illustrated example, a part of the first receiving part 426 c is located above the upper edge 15 . However, the entirety of the first receiving part 426 c may be located below the upper edge 15 . In some embodiments, the first binding hook 426 may include a plurality of first receiving parts to adjust the ankle cap 41 relative to the binding frame 1 .
[0039] In some embodiments, there can be a plurality, for example two, of the first binding hooks 426 on each binding B 1 , each of which can include a first receiving part 426 c. In the case of two first binding hooks 426 , the first binding hooks 426 can be arranged serially/linearly so that one of the binding hooks 426 is disposed between the other binding hook 426 and the attaching member 7 A, or the binding hooks 426 can be arranged side-by-side so they are generally equally spaced from the attaching member 7 A. When the binding hooks 426 are arranged serially/linearly, the engagement member 424 can engage with either one of the binding hooks 426 so as to be selectively engaged by the user with either of the hooks 426 to add an additional tightness adjustment option.
[0040] In another embodiment, the first engagement member 424 can include a plurality, for example two, of the engagement portions 424 c. In the case of two of the engagement portions 424 c and two of the binding hooks 426 , the engagement portions 424 c can be arranged serially/linearly so that one of the engagement portions 424 c is disposed between the other engagement portion 424 c and the traction element 421 e, or the engagement portions 424 c can be arranged side-by-side so they are generally equally spaced from the traction element 421 e. When the engagement portions 424 c are arranged serially/linearly, each one of the engagement portions 424 c can engage with one of the binding hooks 426 at the same time.
[0041] As shown in FIG. 5 , the ankle cap strap 43 is attached to the binding frame 1 , and to the ankle cap 41 . Specifically, the ankle cap strap 43 is attached to the second side surface 12 of the binding frame 1 by the attaching member 7 B. In addition, the ankle cap strap 43 can be attached to the second end portion 41 b of the ankle cap 41 , for example by two attaching members 7 D. The two attaching members 7 D can be, for example, quick adjust screws. The ankle cap strap 43 can also include a plurality of adjustment holes 432 formed therein that are engageable with the attaching members 7 D to adjust the ankle cap 41 relative to the binding frame 1 . The ankle cap strap 43 can be formed of any materials that are suitable for performing the functions of the ankle cap strap 43 , for example plastic, carbon fiber, or kevlar. In one embodiment, the ankle cap strap 43 may include one or more thin metal cables coated in rubber/plastic so as not to wear into the boot. In another embodiment, the strap 43 (and/or the strap 53 described below) could be replaced with a buckle mechanism similar to the buckle mechanism 42 (and/or the buckle mechanism 52 described below).
[0042] With reference to FIGS. 2, and 4-6 , the toe cap 51 is connected to the binding frame 1 . The toe cap 51 helps to hold the snowboard rider's boot to the binding frame 1 . The toe cap 51 includes a first end portion 51 a and a second end portion 51 b. In the illustrated embodiment, the first end portion 51 a is disposed at one end of the toe cap 51 in a width direction of the binding frame 1 . The second end portion 51 b is disposed at the other end of the toe cap 51 in the width direction.
[0043] The toe cap buckle mechanism 52 connects the toe cap 51 to one side of the binding frame 1 . In the illustrated example, the toe cap buckle mechanism 52 is attached to the first end portion 51 a of the toe cap 51 , and is releasably attachable to the first side surface 11 of the binding frame 1 . The toe cap buckle mechanism 52 can have two primary conditions—a connected condition and a disconnected condition. When the toe cap buckle mechanism 52 is in the connected condition, the toe cap 51 and the binding frame 1 are connected by the toe cap buckle mechanism 52 (see FIGS. 2, 5, and 6 ). On the other hand, when the toe cap buckle mechanism 52 is in the disconnected condition, the toe cap 51 and the binding frame 1 are not connected by the toe cap buckle mechanism 52 (see FIG. 14 ).
[0044] The toe cap buckle mechanism 52 includes a second buckle 521 (also referred to as a second buckle means), a second engagement member 524 (also referred to as a second engagement means), and a second binding hook 526 (also referred to as a second binding hook means).
[0045] The second buckle 521 is attached to the toe cap 51 . Specifically, the second buckle 521 is attached to the first end portion 51 a of the toe cap 51 . The second buckle 521 can be made of metal, plastic or other suitable material. The second buckle 521 includes a support base 521 a, a lever 521 c, and a traction element 521 e.
[0046] As shown in FIGS. 4, and 6 , the support base 521 a is attached to the first end portion 51 a of the toe cap 51 . The lever 521 c is pivotally attached to the support base 521 a through a pin 521 g. The traction element 521 e is pivotally attached to the lever 521 c through a pin 521 h. In the illustrated example, the traction element 521 e includes a rod 521 m and a housing 521 n. The rod 521 m of the traction element 521 e can be rotated into and out of the housing 521 n to adjust the length of the traction element 421 e. Thus, the connection tightness of the toe cap assembly 50 can be adjusted by adjusting the length of the traction element 421 e. In some embodiments, the rod 521 m of the traction element 521 e may not be adjustable. As indicated above, the buckle mechanism 52 is generally similar in construction and operation to buckle mechanisms used on conventional ski boots except for the binding hook 526 .
[0047] The second engagement member 524 is connected to the second buckle 521 . Specifically, the second engagement member 524 is pivotally connected to the traction element 521 e of the second buckle 521 through a pin 528 . The second engagement member 524 can be made of metal, plastic or other suitable material. The second engagement member 524 has an opening 524 a. Though FIG. 6 shows an example in which the opening 524 a is rectangular, the shape of opening 524 a is not limited to rectangular. The second engagement member 524 includes an engagement portion 524 c, for example a pin or bar, that is engageable with the second binding hook 526 . The engagement portion 524 c defines a part of the opening 524 a.
[0048] The second binding hook 526 is attached on the binding frame 1 . In this embodiment, the second binding hook 526 is non-rotatably attached to the binding frame 1 by an attaching member 7 C at a location to be engageable with the second engagement member 524 . The second binding hook 526 can be made of metal, plastic or other suitable material.
[0049] As shown in FIG. 6 , the second binding hook 526 includes a second base part 526 a and a second receiving part 526 c. The second base part 526 a is attached to the binding frame 1 by the attaching member 7 C. The second base part 526 a directly contacts the first side surface 11 of the binding frame 1 . The second receiving part 526 c is integrally formed on the second base part 526 a. The second receiving part 526 c receives a part of the second engagement member 524 (specifically, the engagement portion 524 c ) when the second binding hook 526 is engaged with the second engagement member 524 . The second receiving part 526 c directly contacts the engagement portion 524 c of the second engagement member 524 when the second binding hook 526 is engaged with the second engagement member 524 . The second receiving part 526 c is disposed in the opening 524 a of the second engagement member 524 , when the second binding hook 526 is engaged with the second engagement member 524 . As shown in FIG. 6 , the second receiving part 526 c overlaps the binding frame 1 in a side view. The second receiving part 526 c includes a portion located below or flush with the upper edge 15 . In this illustrated example, the entirety of the second receiving part 526 c is located below or flush with the upper edge 15 . However, in other embodiments, a portion of the second receiving part 526 c may be located above the upper edge 15 . In some embodiments, the second binding hook 526 may include a plurality of second receiving parts to adjust the ankle cap 41 relative to the binding frame 1 .
[0050] In some embodiments, like with the first binding hook 426 and the first engagement member 424 , there can be a plurality, for example two, of the second binding hooks 526 , and also a plurality, for example two, of the engagement portions 524 c. The plurality of the second binding hooks 526 and the plurality of the second engagement portions 524 c can be arranged and function like described above for the first binding hooks 426 and the first engagement members 424 .
[0051] As shown in FIG. 5 , the toe cap strap 53 is attached to the binding frame 1 , and to the toe cap 51 . Specifically, the toe cap strap 53 is attached to the second side surface 12 of the binding frame 1 by one of the attaching members 7 C. The attaching member 7 C can be, for example, a quick adjust screw. In addition, the toe cap strap 53 can be attached to the second end portion 51 b of the toe cap 51 by two attaching members 7 C. The two attaching members can be, for example, quick adjust screws. The toe cap strap 53 can also include a plurality of adjustment holes 532 formed therein that are engageable with the attaching members to adjust the toe cap 51 relative to the binding frame 1 . The toe cap strap 53 can be formed of any materials that are suitable for performing the functions of the toe cap strap 53 , for example plastic. The toe cap strap 53 may include two thin metal cables coated in rubber/plastic so as not to wear into the boot.
[0052] As shown in FIG. 1 , the snowboard body B 2 includes an upper surface 81 and a lower surface 82 . The upper surface 81 and the lower surface 82 can be generally flat. However, opposite ends 83 , 84 of the snowboard can be curved upwardly in conventional manner. In the snowboard A 1 , the snowboard bindings B 1 are attached to the upper surface 81 . Specifically, each binding frame 1 of the snowboard bindings B 1 is attached to the upper surface 81 via the base plate 3 . For this purpose, in the illustrated example, each base plate 3 of the snowboard bindings B 1 is attached to the upper surface 81 by a plurality of attaching members (not shown) in a conventional manner.
[0053] The operation of the snowboard A 1 and the snowboard bindings B 1 should be readily apparent to a person of skill in the art from the foregoing description and the drawings. However, an example use of the snowboard bindings B 1 is briefly explained below.
[0054] With the buckle mechanisms 42 , 52 initially disconnected from the hooks 426 , 526 , the user moves the assemblies 40 , 50 out of the way and steps into the binding frames 1 . When the user's boots are properly positioned in the binding frames 1 , the user pulls the assemblies 40 , 50 over the boots and pivots the levers 421 c, 521 c upward to the position shown in FIG. 13 . At the same time, the engagement portions 424 c, 524 c are positioned near the binding hooks 426 , 526 .
[0055] Referring to FIG. 14 , the engagement portions 424 c, 524 c are then maneuvered behind the receiving parts 426 c, 526 c. The levers 421 c, 521 c are then rotated toward the closed position. As the levers 421 c, 521 c are rotated, they pull the traction elements 421 e, 521 e which in turn pull the engagement members 424 , 524 so that the engagement portions 424 c, 524 c gradually become locked behind the receiving parts 426 c, 526 c of the binding hooks 426 , 526 . The levers 421 c , 521 c continue to be rotated until they are fully closed (shown in FIGS. 2-4 and 6 ) and the engagement members 424 , 524 are locked to the binding hooks 426 , 526 . Removal works in an opposite manner, with the levers 421 c, 52 c manually rotated to the open position shown in FIG. 13 which frees the engagement portions 424 c, 524 c from the receiving parts 426 c, 526 c.
[0056] The described bindings permit connection of the engagement members to the binding hooks using one hand instead of requiring both hands. In addition, the described bindings have only two straps on each binding instead of four straps. Further, the user can pre-adjust the straps 43 , 53 and the traction elements 421 e, 521 e to obtain the desired tightness. Thereafter, each time that the user fastens the bindings, the same level of tightness can be achieved without requiring the user to adjust each time the user connects to the bindings. Further, because the engagement members are received by the receiving part of the binding hooks, ice and snow are prevented from building up in the binding hooks. Further, the binding hooks are non-rotatably attached to the binding frame. As a result, the snowboard A 1 can respond instantly to the rider's movement (for example when ollieing and spinning or applying nose or tail pressure) and extra delay of the movement of the snowboard A 1 that can be caused by pivotally mounted straps can be prevented.
[0057] FIG. 15 is a front perspective view showing a snowboard binding according to another embodiment.
[0058] The snowboard binding shown in FIG. 15 is different from the snowboard binding shown in FIG. 4 in that a puck or circular disk 34 is mounted on the base plate 3 . Other structures in the snowboard binding in FIG. 15 are the same as the foregoing embodiment in FIGS. 1-14 . The puck 34 shown in FIG. 15 is a circular plate and can be used for adjusting an angle of the binding frame 1 on the snowboard body. For example, once the user loosens screws (not shown) that fix the puck 34 to the snowboard body, the user can rotate the binding frame 1 relative to the puck 34 . Once the desired angle of the binding frame 1 is achieved, the user then tightens the screws of the puck 34 which clamps the base plate 3 and fixes the position of the binding frame 1 . The construction and operation of a binding frame with a puck-like disc permitting adjustment of the binding frame is known in the art.
[0059] The examples disclosed in this application are to be considered in all respects as illustrative and not limitative. The scope of the invention is indicated by the appended claims rather than by the foregoing description; and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein. | A snowboard binding that eliminates the ratchet-type connection used in conventional snowboard bindings. Instead, the snowboard binding incorporates a connection mechanism that is somewhat similar to a ski-boot style connector, and that uses only two straps on each binding compared to the traditional four straps. In addition, the connection mechanism can be pre-adjusted by the user to the desired connection pressure. Once the desired pre-adjustment is reached, the user can simply step into the binding and connect the connection mechanism without needing to adjust the connection pressure or tightness during mounting the user's foot or boot to the board as with conventional snowboard bindings. | 0 |
BACKGROUND OF THE INVENTION
[0001] Following either popular or celebrity fashion trends, more and more consumers use hair treatments to pursue fashionable hairstyles. The color treatments include hair coloring, highlighting, and bleaching. Although these hairstyle techniques greatly satisfy consumers' needs, they also cause severe hair damage, especially when the treatments are used repetitively. Moreover, various daily actions to the hair, for example hair brushing, hair blow-drying, and sun light exposure add more damage to the hair.
[0002] It is generally accepted that chemical treatment and/or UV exposure causes hair damage, which results in increased porosity and swelling of the hair cuticle. That is why hair becomes rough, coarse and dull when damage happens to the hair. Furthermore, hair looses its tensile strength when damage occurs in the hair's cortex, since the cortex is believed to be primarily responsible for the tensile properties of human hair. The cuticle of the hair is an important factor in torsional mechanical properties, but its contribution to bulk longitudinal mechanical strength is minor. Therefore, the measurement of tensile strength not only is an evaluation method of hair damage, but also an indication to determine if damage has penetrated to the cortex. One of the ways to restore natural quality of damaged hair is to recover its reduced tensile strength.
[0003] A method of treating hair that addresses at least some of the above-mentioned problems is therefore desired.
SUMMARY OF THE INVENTION
[0004] The present disclosure provides for a method of treating one or more hair shafts, each hair shaft including a cuticle layer and a cortex enclosed in the cuticle layer of damaged hair comprising: selecting one or more PolyDADMAC polymer that can penetrate the hair shafts with a pore size of about 5 angstroms to about 5,000 angstroms; and treating the hair shafts by applying an effective amount of a composition containing said polymers to said hair shafts.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 shows a statistical analysis of tensile strength of Polymer II against control (no polymer addition).
[0006] FIG. 2 shows a tensile strength increment of Polymer I and II against control (no polymer addition).
[0007] FIG. 3 shows a statistical analysis of tensile strength of Polymer IV against control (no polymer addition).
[0008] FIG. 4 shows a surface area analysis study of hair treated with Polymer II and control (no polymer addition).
DETAILED DESCRIPTION OF THE INVENTION
[0009] Definitions: “PolyDADMAC” means poly(diallyldimethylammonium chloride).
[0010] Chemical damage hair means hair damage is caused by chemical treatment which includes hair perm, hair highlight, hair color, and hair relaxer.
[0011] Thermal damage hair means hair damage is caused by thermal treatment which includes hair blow dryer, heat hair setting.
[0012] UV damage hair means hair damage is caused by excess UV exposure.
[0013] As stated above, one or more hair shafts are treated with one or more polymers that can penetrate a hair shaft with a pore size of about 5 angstroms to about 5000 angstroms.
[0014] In one embodiment, the hair shaft pore size is between about 10 angstroms and about 1000 angstroms.
[0015] In another embodiment, the purpose of the treatment is to nourish and/or repair the hair shaft.
[0016] In another embodiment, the purpose of the treatment is to improve the tensile strength of the hair.
[0017] Generally, the polymers utilized should be of sufficient size to penetrate into the cortex of the hair shaft, but not easily migrate out of the cortex. One of ordinary skill in the art could determine whether a polymer meets this particularly criteria without undue experimentation. Therefore, polymers that are linear, branched, hyperbranched, or dendritic may meet this criteria.
[0018] Various types and conformations of polymers may be utilized to treat a hair shaft.
[0019] In one embodiment, the PolyDADMAC polymer is selected from the groups consisting of homopolymers, copolymers, terpolymers, and a combination thereof.
[0020] In another embodiment, the PolyDADMAC polymer is selected from the group consisting of cationic polymers.
[0021] In another embodiment, the PolyDADMAC polymer is selected from the group consisting of: PolyDADMAC, poly(sodium acrylate), and a combination thereof
[0022] In another embodiment, the polymers have a weight average molecular weight of from about 300 daltons to about 80,000 daltons, excluding PolyDADMAC wherein the upper limit of said range for PolyDADMAC is less than 15,000 daltons.
[0023] In another embodiment, the PolyDADMAC has a weight average molecular weight of from about 1,500 to less than 15,000.
[0024] In another embodiment the range for the weight percent of the PolyDADMAC is 0.1% to about 10% weight percent, based upon actives in said composition.
[0025] In another embodiment, the PolyDADMAC has the weight average molecular weight of about 1,200 daltons to about 5,700 daltons.
[0026] In another embodiment, the poly(sodium acrylate) has a weight average molecular weight of about 300 daltons to about 30,000 daltons.
[0027] In another embodiment, the poly(sodium acrylate) has a weight average molecular weight of about 3,000 daltons to about 15,000 daltons.
[0028] Hair shafts are damaged in various ways, e.g. by over-processing hair, more specifically, colored hair, relaxed hair, over-bleaching hair, UV-exposure to hair, thermal treatment of hair and/or by environmental stress.
[0029] In one embodiment, the polymers are utilized to treat hair that is chemically damaged and/or UV damaged and/or thermal damaged.
[0030] In another embodiment, the polymers may be utilized to prevent hair from being damaged or inhibit the rate at which hair is damaged, or repair the damaged hair.
[0031] The composition may further comprise one or more cosmetically acceptable excipients. A cosmetically acceptable excipient is a non-toxic, non-irritating substance which when mixed with the one or more polymers of this invention makes the polymers more suitable to be applied to the hair.
[0032] In one embodiment, the excipients are selected from the group consisting of water, saccharides, surface active agents, humectants, petrolatum, mineral oil, fatty alcohols, fatty ester emollients, waxes and silicone-containing waxes, silicone oil, silicone fluid, silicone surfactants, volatile hydrocarbon oils, quaternary nitrogen compounds, amine functionalized silicones, conditioning polymers, rheology modifiers, antioxidants, sunscreen active agents, mono, di or tri-long chain amines from about C 10 to C 22 , long chain fatty amines from about C 10 to C 22 , fatty alcohols, ethoxylated fatty alcohols and di-tail phospholipids.
[0033] The composition containing the PolyDADMAC polymer may be in various forms. One of ordinary skill in the art would know how to formulate the polymers with cosmetically acceptable excipients and/or other components of a composition.
[0034] In one embodiment, the composition is selected from the group consisting of shampoos, conditioners, permanent waves, hair relaxers, hair bleaches, hair detangling lotion, styling gel, styling glazes, spray foams, styling creams, styling waxes, styling lotions, mousses, spray gets, pomades, hair coloring preparations, temporary and permanent hair colors, color conditioners, hair lighteners, coloring and non-coloring hair rinses, hair tints, hair wave sets, permanent waves, curling, hair straighteners, hair grooming aids, hair tonics, hair dressings and oxidative products, spritzes, styling waxes and balms.
[0035] The following example is not meant to be limiting.
EXAMPLE
[0036] For this EXAMPLE section, the weight-average molecular weight of polymer was determined by a size-exclusion chromatography/multi-angle laser light scattering (or SEC/MALLS) technique. Size exclusion chromatography (SEC) was performed by using a series of TSK-GEL PW columns from TOSOH BIOSCIENCE, a multi-angle laser light scattering detector (MALLS, model: DAWN DSP-F) and an interferometric refractometer (OPTILAP DSP) from Wyatt Technology. Data collection and analysis were performed with ASTRA software from Wyatt Technology.
[0000]
Key for Example
Polymer
Chemistry
Molecular Weight
I
PolyDADMAC
1,300
II
PolyDADMAC
3,800
III
PolyDADMAC
5,700
IV
PolyDADMAC
150,000
Example Particulars
[0037] a. Tensile Strength Measurements
[0038] A tensile strength test was done on chemically damaged hair. The protocol included the following steps.
[0039] Virgin brown hair was bleached by immersion in 6% hydrogen peroxide solution containing 1.7% ammonium hydroxide and 10% urea at 40±1° C. for 15 minutes. The bleached hair was then treated in 1% (solid) polymer solution for 5 minutes and rinsed under deionized water for 10 seconds.
[0040] The diameter of forty hair strands was randomly selected from each treated and untreated (“control”) testing group were measured using a Fiber Dimensional Analysis System (Mitutoyo, Model LSM 5000). The hair samples were placed in a DiaStron Miniature Tensile Tester (Model 170/670) for the determination of tensile strength in a wet condition. The total work force normalized with hair diameter was calculated by using DiaStron software (MTTWIN Application Software Version 5.0). The mean values obtained from 40 hair strands were analyzed using Tukey HSD statistical analysis to compare all the testing pairs (ANOVA one-way analysis of variance from JMP statistical software, SAS Institute, Cary, N.C., U.S). The testing results and statistical analysis are summarized in following tables and figures. Results for cationic polymers are shown in Table 1 and Table 2. Results for anionic polymers are shown in Table 3 and Table 4.
[0000]
TABLE 1
Chemistry and Molecular Weight of the Cationic Polymers
Name
Molecular Weight
Chemistry
Polymer IV
150,000
PolyDADMAC
Polymer II
3800
PolyDADMAC
[0000]
TABLE 2
Tensile Strength Measurement for the Treatment Listed in Table 1
Sample Name
Tensile Strength (J)
% Improvement
Control
0.00104
Polymer IV
0.00107
≈0
Polymer II
0.00122
17.31
[0041] It is clear from Table 1, Table 2, and FIG. 1 that the low molecular weight of Polymer II significantly improves tensile strength for about 17% while statistical analysis shows that there is no significant difference in tensile strength between control and Polymer IV ( FIG. 3 ). Experiments were performed with Polymer I, a low molecular weight PolyDADMAC. The results are shown in FIG. 2 . These results show that the penetration of the low molecular weight polymer can recover the lost tensile strength of damaged hair.
[0000] b. Surface Area Measurements
[0042] Surface area analysis was also done both on treated and untreated hair tresses to understand if low molecular weight polymer species penetrated the hair shaft. The protocol included the following steps.
[0043] Surface area analysis was carried out via a nitrogen adsorption analysis. Nitrogen adsorption analyses on hair samples were conducted using a Quantachrome Autosorb-1C instrument. Samples were cut to very fine pieces and then added to a sample cell where they were placed under vacuum at 145° C. for 0.5 hours. Complete water removal is necessary to obtain accurate measurements, which is why 145° C. was used. This value is based on the data collected from Differential Scanning Calorimetry (DSC) in which dehydration peak appears at around 125° C. A 5-pt BET (Brunauer-Emmett-Teller) surface area analysis was used for all samples. The decrease of surface area indicates that the low molecular weight polymers penetrated the hair and took up the pore spaces, which are distributed throughout the hair shaft.
[0044] The results for the surface analysis study are illustrated in FIG. 5 . Gas sorption analysis from FIG. 5 shows the significant decrease in surface area of hair shafts treated with Polymer II, which illustrates the effective penetration of low molecular weight polymers into the hair shafts. | A method of treating one or more hair shafts, each hair shaft including a cuticle layer and a cortex enclosed in the cuticle layer is disclosed. The method comprises: selecting one or more polymers that can penetrate the hair shafts with a pore size of about 5 angstroms to about 5000 angstroms; and treating the hair shafts by applying an effective amount of a composition containing said polymers to said hair shafts. | 0 |
TECHNICAL FIELD
[0001] The present invention concerns implantable heart monitors, such as defibrillators and cardioverters, particularly structures and methods for capacitors in such devices.
BACKGROUND
[0002] Since the early 1980s, thousands of patients prone to irregular and sometimes life-threatening heart rhythms have had miniature heart monitors, particularly defibrillators and cardioverters, implanted in their bodies, specifically in the upper chest area above their hearts. These devices detect onset of abnormal heart rhythms and automatically apply corrective electrical therapy, specifically one or more bursts of electric current, to hearts. When the bursts of electric current are properly sized and timed, they restore normal heart function without human intervention, sparing patients considerable discomfort and often saving their lives.
[0003] The typical defibrillator or cardioverter includes a set of electrical leads, which extend from a sealed housing into the walls of a heart after implantation. Within the housing are a battery for supplying power, monitoring circuitry for detecting abnormal heart rhythms, and at least one capacitor for delivering bursts of electric current through the leads to the heart.
[0004] The capacitor is often times an aluminum electrolytic capacitor, which takes a flat or cylindrical form. The flat form of this type capacitor generally includes a stack of flat capacitor elements or modules, each comprising two or more aluminum foils and an electrolyte-soaked separator between them. The stack of flat modules, often D-shaped, are housed in a sealed aluminum case of similar shape. The cylindrical form includes one long capacitor module that is rolled up and housed in a round tubular, or cylindrical, aluminum case.
[0005] One problem with both the flat and cylindrical forms of these capacitors is that during normal operation their capacitor modules electro-chemically generate gases, such as hydrogen, that are trapped inside the sealed cases. Over the life of some of these capacitors, the trapped gases accumulate and exert considerable pressure on the cases, often forcing them to swell and permanently distort. This swelling is problematic not only because of the cramped spacing within implantable heart monitors, but also because it causes portions of some foils to separate from adjacent separators and to be starved of electrolyte. This starvation increases equivalent series resistances (ESR) and reduces capacitance, or energy-storage capacity, of the capacitors.
[0006] To address this problem, some capacitor manufacturers have sought to make their sealed cases with thicker walls to resist swelling. However, the inventors have recognized that this solution is of limited value because it often increases the size and weight of capacitors and/or reduces the space available for components, such as aluminum foil, which contribute to the total capacitance, or energy-storage density, of the capacitors. Additionally, some capacitor manufacturers have introduced organic nitro-compounds to the electrolyte of the capacitor to reduce production of hydrogen gas. However, these compounds have not proven to successfully reduce hydrogen gas build-up in all cases.
[0007] Accordingly, the inventors identified an unmet need for better ways of avoiding or reducing capacitor swelling, particularly for capacitors in implantable heart monitors.
SUMMARY
[0008] To address this and other needs, the inventors devised novel structures and related capacitors and devices that include hydrogen- or other gas-getting materials and thus prevent the development of excessive pressures within their cases. One exemplary capacitor includes at least aluminum and titanium. Another exemplary capacitor includes the titanium in the form of a titanium and titanium-oxide coating on an aluminum cathode. In this embodiment, the titanium absorbs or adsorbs hydrogen gas, and the titanium oxide, which has a much higher dielectric constant than the aluminum oxide present in conventional aluminum electrolytic capacitors, increases capacitance.
[0009] Other aspects of the invention include an implantable heart monitor, such as pacemaker, defibrillator, cardioverter, or defibrillator-cardioverter, which comprises one or more of the novel capacitors or other related structures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a cross-sectional view of an exemplary structure embodying the present invention.
[0011] [0011]FIG. 2 is a perspective view of an exemplary flat aluminum electrolytic capacitor 100 including a generic pressure-relief mechanism 120 , embodying the present invention.
[0012] [0012]FIG. 3 is a perspective view of an exemplary cylindrical electrolytic capacitor 200 including a generic pressure-relief mechanism 220 embodying the present invention.
[0013] [0013]FIG. 4 is a block diagram of an exemplary implantable heart monitor 400 embodying the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0014] The following detailed description, which incorporates FIGS. 1 - 4 and the appended claims, describes and illustrates one or more specific embodiments of the invention. These embodiments, offered not to limit, but to exemplify and teach, are shown and described in sufficient detail to enable those skilled in the art to implement or practice the invention. Thus, where appropriate to avoid obscuring the invention, the description may omit certain information known to those of skill in the art.
[0015] [0015]FIG. 1 shows an exemplary structure 100 incorporating teachings of the present invention. Structure 100 includes an aluminum substrate 110 and coat structures 120 and 130 .
[0016] Aluminum substrate 110 has opposing major surfaces 112 and 114 , which define a nominal thickness 116 . In the exemplary embodiment, aluminum substrate 110 consists essentially of a commercially available high-purity aluminum, and nominal thickness 116 lies in the range of 5-150 micrometers (im.) (Other embodiments use other thicknesses, aluminum concentrations, and possibly even other base metals.) Also in the exemplary embodiment, surfaces 112 and 114 are roughened by chemical etching or other suitable procedure. In some embodiments, the roughened surfaces have an effective surface area 2-5 times that of the “unroughened” surface, and still other embodiments have an effective surface area 200-300 times that of the unroughened surface. Affixed respectively to surfaces 112 and 114 are coat structures 120 and 130 .
[0017] Coat structure 120 includes a non-aluminum hydrogen-absorbent (or gas-getting) layer 122 and a non-aluminum-based dielectric layer 124 . Coat structure 130 , which contacts major surface 114 of substrate 110 , similarly includes a non-aluminum hydrogen-absorbent (or gas-getting) layer 132 and a non-aluminum dielectric layer 134 . As used herein, the term “absorb” and its derivatives includes adsorb.
[0018] In the exemplary embodiment, non-aluminum hydrogen-absorbent layers 122 and 132 consist essentially of titanium and have a substantially uniform thickness in the range of 10-1000 nanometers, for example, 500 nanometers. Dielectric (or insulative) layers 124 and 134 consist essentially of titanium oxide and have a substantially uniform thickness in the range of 0.5-5.0 nanometers. (As used herein the term titanium oxide includes any form of oxidized titanium and thus encompasses, for example, one or more of the following: TiO, TiO 2 , Ti 2 O 3 and Ti 3 O 5 .) Notably, the combination of aluminum and titanium exhibits an increase hydrogen solubility compared to pure titanium, exhibiting for example a hydrogen solubility of 180-310 parts per million (ppm) at room temperature. Titanium oxide has a dielectric constant that ranges from 28 to 60, exceeding the 7-10 range associated with aluminum oxide.
[0019] Other embodiments use titanium-based alloys, titanium-containing compositions, or other gas-absorbent materials, such as palladium, zirconium, niobium, vanadium, and combinations of these materials, that also absorb hydrogen. Some embodiments use palladium-, zirconium-, niobium-, and vanadium-based alloys. Other embodiments also use other dielectrics, such as palladium oxide, zirconium oxide, niobium oxide, or vanadium oxide which may also have a higher dielectric constant than aluminum oxide.
[0020] An exemplary method of forming structure 100 entails providing an aluminum substrate, such as an aluminum foil of desired thickness and surface texture, and completely sputter coating one or both sides of the substrate with titanium to the desired uniform thickness. An exemplary titanium source has a purity of 99.5 percent. Some embodiments may mask off sections of the foil to prevent adherence of the titanium coat and thus define coated and non-coated regions. Still other embodiments may apply titanium to achieve a thickness gradient. Other embodiments may use other physical- or chemical-vapor deposition techniques to deposit the titanium.
[0021] Formation of the titanium oxide in the exemplary embodiment entails exposing the titanium-coated aluminum substrate to ambient air; however, other embodiments use other procedures for forming the titanium oxide. For instance, some may form the oxide under more specific oxygenated, pressurized, and temperature-controlled conditions.
Exemplary Flat Capacitor
[0022] [0022]FIG. 2 shows a pictorial cross-section of an exemplary flat aluminum electrolytic capacitor 200 , incorporating exemplary structure 100 . Capacitor 200 includes a flat-form or pan-type case 210 , a capacitor module 220 , and capacitor terminals 230 and 232 .
[0023] Case 210 , which has a D-shape (not visible in this cross-sectional view), includes at least one wall portion 211 . Wall portion 211 , as shown in inset 2 A, includes an aluminum substrate 212 which is affixed to a coat structure 214 . In the exemplary embodiment, the interface between substrate 212 and coat structure 214 is etched; however, in other embodiments, the interface is smooth or unreached. Coat structure 216 , which is similar in form and function to structure 100 , includes a non-aluminum hydrogen- or gas-ion-getting layer 216 and a non-aluminum-based dielectric 218 . In the exemplary embodiment, substrate 212 comprises titanium, and non-aluminum-based dielectric layer 218 comprises titanium oxide. Coat structure 216 is subject to similar material and form variations as structure 100 .
[0024] Capacitor module 220 , generally representative of one or more stacked capacitor modules, includes a cathodic electrode structure 100 ′, a separator structure 222 and an anodic electrode structure 224 . Specifically, cathodic electrode structure (or cathode) 100 ′ has the same structural format and material composition as structure 100 . Separator structure 222 , which is impregnated with an electrolyte, such as an ethylene-glycol base combined with polyphosphates or ammonium pentaborate, separates cathodic electrode structure 100 ′ from anodic electrode structure 224 . Anodic electrode structure (anode) 224 includes one or more conductive layers, although only one layer is depicted in the simplified figure. For example, some embodiments provide an anodic structure having three or more stacked conductive layers. Additionally, anodic electrode structure 224 may itself include a coat structure based on that of structure 100 , as indicated by broken-line layers 225 and 226 .
[0025] In the exemplary embodiment, cathodic electrode structure 100 ′ has a capacitance greater than that of anodic electrode structure 224 . For example, the cathode capacitance is 100-1000 micro-Farads per square centimeter, and the anode capacitance is 0.8-1.4 micro-Farads per square centimeter. And, separator structure 222 comprises one or more layers of kraft paper impregnated with an electrolyte. Other embodiments, however, use other types of separators. Also, some embodiments include additional separator structures to separate capacitor module 220 from conductive elements in other capacitor modules and/or from portions of capacitor case 210 . Still other embodiments include a heterogeneous set of capacitor modules, with one or more of the modules incorporating teachings of structure 100 .
[0026] Coupled to electrode structures 100 ′ and 224 are capacitor terminals 230 and 232 Capacitor terminal 230 is coupled to cathodic electrode structure 100 ′, and capacitor terminal 232 is coupled to anodic electrode structure 224 . In some embodiments, cathodic electrode structure 100 ′ is electrically coupled to case 210 at a connection point 219 . FIG. 2 shows this electrical connection as a broken line 233 .
[0027] In operation, capacitor 200 generally functions in a conventional manner, with the exception that the cathodic electrode structure and/or case-wall structure provide one or more performance advantages. For example, during charging and discharging of the capacitor, interaction of the electrolyte with the cathodic electrode frees hydrogen ions from the electrolyte, and some of these hydrogen ions pair up or unite to form H 2 molecules, or hydrogen gas. In contrast to conventional aluminum electrolytic capacitors that allow this hydrogen gas to accumulate and exert a mounting pressure on the capacitor case and internal capacitor components, the titanium material in the capacitor, particularly the titanium in the cathodic electrode structure, absorbs hydrogen ions and/or hydrogen gas and thus reduces or eliminates the mounting pressure. More precisely, it is presently believed that some portion of the adsorbed hydrogens atoms diffuse into the titanium coat structure as absorbed hydrogen and that some portion combine with the titanium to produce TiH 2 film, according to
2H ads +Ti→TiH 2 ,
[0028] where the “ads” subscript denotes adsorbed atoms. (See A. M. Shams El. Din et. al, Aluminum Desalination 107, 265-276 (1996.)) Other embodiments may use other materials to absorb hydrogen or to absorb other gases and ions. Titanium itself may absorb gases other than hydrogen.
[0029] Moreover, the titanium oxide in the cathodic electrode structure has a higher dielectric constant than that of aluminum oxide and thus increases the capacitance of the cathodic electrode structure (assuming all other factors equal.). This increase in cathodic capacitance in turn reduces the voltage on the cathode because according to the relationship
C
anode
×V
anode
=C
cathode
×V
cathode
[0030] where C anode and C cathode denote the respective capacitance of the anodic and cathodic structures and V anode and V cathode denote the respective voltages across the anodic and cathodic structures, V cathode is inversely proportional to C cathode . Since hydrogen ions are liberated from the electrolytes at a specific voltage, the reduced cathodic voltage can ultimately inhibit or prevent hydrogen-ion liberation in the first place, further reducing the accumulation of hydrogen gas and its distortion potential.
Exemplary Cylindrical Capacitor
[0031] [0031]FIG. 3 shows an exemplary cylindrical aluminum electrolytic capacitor 300 which incorporates teachings of the present invention and functions in a manner similar to capacitor 200 . Capacitor 300 includes terminals 310 (only one visible in this view), a case 320 , and a rolled capacitor module 330 .
[0032] Specifically, terminals 310 are fastened to a top or header 322 of case 320 via rivets 324 (only one visible in this view). Case 320 , which consists essentially of aluminum in this exemplary embodiment, includes one or more portions that incorporate a coat structure 326 as shown in inset 3 A. (Other embodiments may form the case from other metals and materials alone or in combination with each other or aluminum.) In the exemplary embodiment, coat structure 326 has a similar structural format, material composition, and functionality as that shown and/or described for coat structure 214 in FIG. 2. Rolled capacitor module 430 includes at least one elongated capacitor module, which, as inset 3 B shows, has a cross-sectional structure resembling that shown and/or described for capacitor module 220 in FIG. 2. Rolled capacitor module 330 is rolled around a mandrel region 332 .
Exemplary Implantable Cardiac Rhythm Manager
[0033] [0033]FIG. 4 shows an exemplary implantable cardiac rhythm manager 400 that includes one or more capacitors that incorporate teachings of the exemplary embodiments. Specifically, manager 400 includes a lead system 410 , which after implantation electrically contact strategic portions of a patient's heart, a monitoring circuit 420 for monitoring heart activity through one or more of the leads of lead system 410 , and a therapy (or pulse-generation) circuit 430 which includes one or more capacitors 432 that incorporate one or more of the teachings related to capacitor 200 or 300 . Capacitors 432 are rated for an operating voltage of 390 volts and energy storage of about 14 Joules. Manager 400 operates according to well known and understood principles to generate electrical pulses and perform defibrillation, cardioversion, pacing, and/or other therapeutic or non-therapeutic functions.
Other Exemplary Applications
[0034] In addition to aluminum electrolytic capacitors and implantable cardiac rhythm management systems or devices, the teachings of the present invention are applicable to other systems, devices, and components. For example, other types of capacitors that liberate hydrogen or other gases during operation may include the cases, anodes, and/or cathodes based on the present teachings. Also, other systems and devices that use capacitors, such as those related to photographic flash equipment, may incorporate one or more of the present teachings.
Conclusion
[0035] In furtherance of the art, the inventors have devised not only unique structures that enhance operation of capacitors by preventing development of excessive internal pressures, but also related devices, systems, and methodologies. One exemplary capacitor includes aluminum structures coated with titanium or titanium oxide or more generally with non-aluminum-based, gas- or gas-ion-getting materials or high-dielectric-constant materials.
[0036] The embodiments described herein are intended only to illustrate and teach one or more ways of practicing or implementing the present invention, not to restrict its breadth or scope. The actual scope of the invention, which embraces all ways of practicing or implementing the teachings of the invention, is presently defined by the following claims and their equivalence. | Implantable heart monitors, such as defibrillators and cardioverters, detect abnormal heart rhythms and automatically apply corrective electrical shocks to the hearts of patients. A critical component in these devices are the capacitors that produce the electrical shocks. One problem with some of these capacitors is that during operation they generate internal gases, which over time accumulate and exert pressure on their cases, often forcing the cases to swell or bulge and potentially compromising capacitor and monitor performance. Accordingly, the inventors devised novel capacitors that include titanium and/or other hydrogen-getting materials and structures, for preventing the development of excessive pressures within capacitor cases. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the oil and gas industry and more particularly to a compressor operated piston system for removing fluid build up in a gas well hampering the production of the gas from the well. As is well known in the industry, some gas wells produce fluids. Fluid build up in the casing of a gas well results in a static head hampering or shutting off production of gas from earth formations or perforations in the casing. Therefore many different apparatuses have been employed to remove such fluid, such as a gas lift system or as by pumping, neither being entirely satisfactory.
This invention on the other hand provides an automatic operating system responding to gas pressure sensors and an axial piston assembly which removes fluid from the well bore casing permitting commercial production of gas to the fullest extent possible of a particular gas well.
2. Description of the Prior Art
I do not know of any patents or publications disclosing the apparatus of this invention.
BRIEF SUMMARY OF THE INVENTION
An axial assembly of pistons is axially attached to the depending end of tubing in a gas well and set above the formation or casing perforations. Fluid from the production zone enters the casing through an orifice at the depending end of the piston assembly. The piston assembly in an open position allows fluid from the production formation, after passing through the orifice, to enter the annulus between the tubing and the casing. Fluids in the flow stream separate and settle to the depending limit of the casing and create a static head of back pressure against the orifice which results in decreasing the gas pressure at the well head. This decrease in gas pressure is detected by pressure sensors which releases compressed gas from a recycling tank on the surface of the earth which enters the tubing and forces pistons in the piston assembly downward. The several pistons in the piston assembly multiplies the force of the recycling tank gas pressure so that the injected gas passes outwardly of the piston assembly through exit ports in the depending end thereof and enters the annulus under the trapped liquid in the annulus around the tubing to lift it to the surface of the earth while simultaneously closing the orifice and preventing any loss of injected gas into the earth formation. When the accumulated liquid in the casing annulus has been removed a pressure sensor opens a closed valve in the gas injection line and gas pressure generated by a compressor is directed to the recycling tank while the gas production enters the flow line connected with the gas well head, thus completing one cycle of operation which is automatically repeated when fluid build up in the casing annulus subsequently occurs.
The principal object of this invention is to provide a compressor lift system employing a series of axially connected pistons periodically removing fluid build up in a gas well casing annulus in response to gas well pressure sensors controlling the operation of a compressor and gas recycling tank.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a fragmentary diagrammatic view of a producing gas well;
FIG. 2 is a fragmentary vertical cross-section view 1 ; of a piston assembly in open position taken substantially along line 2 — 2 of FIG. 1;
FIG. 3 is a similar cross section view in piston closed position;
FIG. 4 is a top view of a spacer looking in the direction of the arrows 4 — 4 of FIG. 2; and,
FIG. 5 is a diagram of system components.
DETAILED DESCRIPTION OF THE INVENTION
Description of preferred embodiment.
DETAILED DESCRIPTION OF THE INVENTION
Like characters of reference designate like parts in those figures of the drawings in which they occur.
In the drawings:
The reference numeral 10 indicates a producing gas well having a bore hole 12 terminating in or passing through a gas producing zone 14 and containing a length of casing 16 having a well head 18 at its upper end projecting above the surface of the earth 20 . Gas, not shown, from the earth formation 14 enters the casing through its depending end or through perforations 22 in the casing wall. The well head 18 is normally connected with a tank or other apparatus receiving gas produced by the well 10 by a flow line 50 .
As mentioned hereinabove, such a gas well produces fluid, not shown, which also enters the depending end portion of the casing 16 with the gas and results in a static head of water accumulating in the depending end of the casing which at least hampers or stops the gas from entering the tubing. It is such a gas well that the apparatus of this system is intended to alleviate the fluid problem.
This is accomplished by installing a string of tubing 26 in the casing 16 with a packer 28 at its depending end which is set in the casing 16 at a point above the gas production zone 14 . A series of axially connected superposed pistons, indicated at 30 (FIG. 2 ), are installed in the tubing 26 above perforations 32 in the tubing wall spaced above the packer 28 and below the lowermost limit of the series of pistons 30 .
Operation of the several pistons 30 is accomplished by control apparatus 34 (FIG. 5 ). The control apparatus includes a compressor unit 36 , a recycling gas tank 38 , a pressure supply gas tank or reservoir 40 and an electrical control system 42 and several interconnected components such as valves, pressure sensors and air lines for opening and closing various valves in sequence for operation of the system as will now be described.
A pipe line 44 is connected at one end with the gas well tubing 26 through an air valve 46 and a check valve 48 to the pressure supply tank 40 . The well casing 16 is connected with the air compressor unit 36 by a tubular line 50 through a pressure sensor 52 , an air valve 54 , a regulator 56 , a separator 58 , a pressure regulator 60 and an air valve 62 and a compressor 66 . The compressor unit 36 includes a scrubber 64 communicating with the air valve 62 and the gas compressor 66 by a tubing line 68 having a normally closed valve 69 connected with the tubing line 68 . Compressed gas from the compressor 66 is connected to the recycling tank by a tubular line 70 through a three-way valve 72 and a discharge valve 74 . An outlet of the three-way valve is also connected to the gas sales or discharge line 76 through a check valve 78 . The discharge line 76 is also connected with a pressure sensor 80 upstream from the check valve 78 . The compressor discharge line 70 is provided with a lateral line open to the atmosphere through a normally closed valve 82 and a normally closed manually opened valve 84 . A pressure sensor recycling tank pressure switch 86 is connected with the compressor discharge line 70 adjacent the three-way valve 72 . Gas line 70 is provided with a branch line 25 connecting the separator 58 with the gas sales line 76 downstream with respect to the three-way valve 72 and upstream with respect to the check valve 78 .
The electrical control system 42 includes solenoids 90 , 92 and 94 connected in parallel with the pressure supply tank 40 by other tubing 96 . A bank of batteries 98 includes necessary wiring connecting the electrical energy with the respective solenoid. Solenoid 90 is connected by an air line 100 with the valves 46 and 54 , and solenoid 92 is connected by an air line 102 with the three-way valve 72 , while the solenoid 94 is connected by a line 104 with the air valves 62 , 69 , 82 , and 74 for opening or closing these valves as presently explained.
OPERATION
In operation the compressor 66 is started by utilizing gas from the well head 18 via a bypass line 65 or a propane starter tank supply, not shown. The electrical control panel 42 controls all functions of the compressor as dictated by well head and discharge gas pressure in the well gas line 76 by responding to changes in preset parameters for operating the gas well 10 . Assuming the pressure in line 50 is not above the discharge set point, as controlled by pressure switch 80 or the low pressure set point of pressure switch 81 , the normally closed pneumatic valves 62 and 74 will open while the normally closed valves 69 and 82 will close. This is accomplished by the pressure supplied by the gas well 10 through the line 44 into the air pressure supply tank 40 . The pneumatic pressure supply tank 40 allows the gas to pass from normally open solenoid 94 through tubing line 104 to open valves 62 and 74 and close valves 69 and 82 . When the well pressure in line 50 is above the set point of pressure switch 52 , the solenoid 90 is excited and opens valve 54 and simultaneously closes valve 46 . Gas flows through pneumatic valve 54 and regulator 56 through the compressor scrubber 58 , regulator 60 and valve 62 into the compressor unit 36 . Compressed gas flows through the sales line 70 , normally open valve 74 and the three-way valve 72 , to the recycling tank 38 . When the recycling tank 38 is at preset pressure point, pressure switch 86 excites solenoid 92 and diverts gas flow through the three-way valve 72 to the sales line 76 . The compressor 66 will continue pumping gas until there are pressure changes in the system. In the event pressure in the sales pipe line 76 exceeds set pressure point, the pressure switch 80 excites the solenoid 94 to close valves 62 and 74 . Simultaneously, pressure release opens the valves 69 and 82 to atmosphere, allowing the compressor 66 to run in idle mode by circulating air and keeping the compressor running. Pressure switch 80 or 81 activates solenoid 94 . The delay relay 51 allows the compressor 66 to shift to the idle position and recycle to atmosphere for a predetermined time. After the time interval elapses, solenoid 94 will return to its normally open position. However, if the suction pressure or the discharge of the compressor 66 remains out of set point range, solenoid 94 will automatically be reversed again by pressure switch 80 or 81 before the pneumatic valves have time to change their position. This action will be repeated until the intake or discharge pressure falls to the acceptable pressure range. Should the well have a sudden slug or surge while the compressor 66 is in the idle mode the gas may pass through the bypass line 25 and into the sales line 76 . When the well head pressure decreases as the result of liquid in the bore hole, and the result of this liquid in line 50 , the pressure drops below the set point of pressure switch 52 , and excites solenoid 90 to close valve 54 and open valve 46 allowing the pressurized gas in the recycling tank 38 to enter the well tubing 26 through line 44 , putting pressure on the piston assembly 30 .
The piston assembly 30 consists of a series of independent axially connected piston housings, as mentioned hereinabove, separated from each other by apertured partitions 33 which are cylindrical with apertures adjacent its periphery and containing a central threaded bore to axially attach the piston housings 31 to each other and the piston stem guide 35 . The spacers also align each piston guide 35 and pistons 39 with each other, allowing each piston stem 37 to extend axially as the depending piston 39 is moved downwardly by the gas being injected into the well tubing 26 . The injected gas enters the top of each piston housing 31 through port holes 41 . As the injected gas enters in the piston assembly 30 , it places pressure on the top of each piston 39 . This pressure causes the piston 39 enclosed in each piston housing 31 to move downward against its return spring 29 placing axial pressure on its stem 37 and axial pressure of the stem 37 on the depending piston in the attached piston housing. Each piston 39 is sealed by an O-ring 43 . This action multiplies the force of the gas being injected from the recycling tank 38 by the surface area of the combined pistons 39 , thus enabling the force being injected into the piston housing to oppose a much larger force, and close the lowermost piston stem 45 on the packer seat 47 preventing gas and liquid from the producing formation 14 entering the piston assembly 30 . By closing the orifice 47 to the production formation of the well, the gas being injected will exit the well tubing port holes 32 and enter the annulus 32 ′ between the tubing 26 and the well casing 16 .
The apparatus control valve 54 is closed during gas injection from the recycling tank 38 . The injection period is closed by the preset time delay relay 91 in the electric control system 42 . At the end of time delay, the valve 54 is opened and injected gas and liquid exit the well head 18 .
The injected gas is restricted from returning to the piston assembly by check valve 49 during the cycling process. One-way bleed valves 67 in the bottom of each piston housing 31 allows each piston to move downward. The one-way bleed valves 67 allow any air or gas trapped in the lower chamber of the piston housing to bleed off. The remaining downward pressure on the piston assembly 31 is dissipated by the time delay of relay 91 , holding open the valve 46 which allows the injected pressure to dissipate back into the recycling tank 38 . This cycle is repeated each time the static head of the liquid is sufficient to lower the well head pressure.
Obviously the invention is susceptible to changes or alterations without defeating its practicability. Therefore, I do not wish to be confined to the preferred embodiments shown in the drawings and described herein. | An axial assembly of pistons is axially disposed in the depending end of tubing in a gas well and packer set above the formation. Gas and fluid from the production zone enters the casing through an orifice below the piston assembly. Fluid in the annulus between the tubing and the casing creates a static head of back pressure against the orifice resulting in decreasing the gas pressure at the well head or flow line, which is sensed by pressure sensors to energize a compressor generating gas under pressure forced down the tubing to move piston rods and close the orifice. The gas pressure lifts the fluid in the annulus to the well head and flow line connected therewith. This cycle is repeated each time gas pressure falls below a predetermined pressure at the well head or flow line. | 4 |
TECHNICAL FIELD
This invention relates to well tools and processes of preparing subterranean formations in wells for production and more particularly to well tools and processes for performing downhole operations such as formation perforating and the like while isolating the subterranean formation from the remainder of the well.
BACKGROUND OF THE INVENTION
In the past it has been common to enhance production of a subterranean hydrocarbon formation by lowering a perforator assembly or the like into the well. The perforator assembly is aligned with the subterranean formation and the perforator is actuated to open or expose the formation. In some situations, perforation is performed below a temporary packer which was removed with the perforator once perforation is complete. Such procedures expose the hydrocarbon formation to caustic well fluids in the well bore. It has been found that the formation subsequently can be damaged by exposure to the well fluids during the period after the perforator assembly is removed and before the formation can be isolated from the remainder of the well. Therefore, an apparatus and method is needed to isolate the formation from well fluids while perforator assemblies or the like are removed from the well.
SUMMARY OF THE INVENTION
In accordance with the present invention, a tool assembly is provided which utilizes a production packer above a perforator tool to seal or isolate the perforated formation from the remainder of the well. A production assembly is connected to and located below the perforator. According to the method of the present invention, the tool assembly is lowered into position such that the perforator is adjacent the subterranean hydrocarbon-bearing formation. Thereafter the packer engages the casing above the formation. The perforator tool is operated to create fluid flow between the formation and the well. Once perforation is completed the perforator tool is retrieved through the packer. The production packer in the well remains in place above the formation. As the perforator tool is retrieved, the production assembly moves up to connect to and seal the packer. Finally, the perforator tool is disconnected from the production assembly and removed from the well.
In other embodiments the perforator tool can be replaced with different downhole tools used in other processes such as acidizing, stimulation, and other types of formation treatments and the like, where isolating the formation from the well fluids is necessary or desired.
BRIEF DESCRIPTION OF THE DRAWING
The accompanying drawing is incorporated into and forms a part of the specification to illustrate examples of the present invention. This drawing together with the description serves to explain the principles of the inventions. The drawings are only included for purposes of illustrating preferred and alternative examples of how the inventions can be made and used and are not to be construed as limiting the inventions to only the illustrated and described examples. Various advantages and features of the present inventions will be apparent from a consideration of the drawings in which:
FIG. 1 is a schematic view of the lower portion of a well with the perforator isolation apparatus of the present invention positioned for practicing the well treatment method of this invention;
FIG. 2 is a schematic view similar to FIG. 1 showing the apparatus in position to perform the later steps of setting the packer and perforating the well of the well treatment method of this invention;
FIG. 3 is schematic view similar to FIG. 1 showing the apparatus in position to perform the step of pulling the perforator through the packer while sealing off the packer of the well treatment method of the present invention;
FIG. 4 is a schematic view similar to FIG. 1 showing the apparatus in position for performing the step of disconnecting the perforator assembly from the packer and retrieving the perforator of the well treatment method of the present invention;
FIGS. 5a-5h together form FIG. 5 which is a longitudinal view in section and elevation of the perforator isolation apparatus of the present invention in a running condition;
FIG. 6 is a fragmentary sectional longitudinal view illustrating the female latch portion of the apparatus of the present invention with the latch element removed for clarity;
FIG. 7 is a fragmentary sectional longitudinal view illustrating the female latch portion with the latch element shown in the upper position;
FIG. 8 is a fragmentary sectional longitudinal view illustrating the female latch portion with the latch element showing the lower position;
FIG. 9 is a fragmentary sectional longitudinal view illustrating the latch portion of the apparatus of the present invention; and
FIG. 10 is a fragmentary longitudinal section view illustrating the latch portion of the apparatus of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present inventions will be described by referring to drawings showing and describing examples of how the inventions can be made and used. In these drawings the same reference characters are used throughout the several views to indicate like or corresponding parts. In these figures and the accompanying description arrow "C" is used to indicate the upward or uphole direction. The reverse of arrow "C" refers to the downward or downhole direction. The upward and downward directions used herein are for reference purposes only, and it is appreciated that not all wells extend vertically, and that the present inventions have utility in nonvertical well configurations.
In FIGS. 1 through 4, one example of a configuration using the present invention is shown schematically in the form of a well perforator isolation apparatus 8 positioned downhole in a well casing 10. Apparatus 8 is assembled at the surface and lowered by running tubing 12, wire line or the like. Apparatus 8 is positioned adjacent to a prospective hydrocarbon-bearing subterranean formation 16. Apparatus 8 is manipulated by running tool 100 connected to running tubing 12. Releasably connected to and supported from the running tool is a production packer 200 which in the embodiment shown is selectively operated by actuator 300. Located below and connected to actuator 300 is female latch assembly 400.
Referring briefly to FIGS. 5b, 5c and 5d, tubing 14 extends through a central passageway 210 defined in packer 200, actuator 300, and female latch 400 to running tool 100. Tubing 14 supports perforator assembly 500 shown positioned adjacent to subterranean formation 16. Perforator assembly 500 is used for perforating casing 10 and subterranean formation 16 as desired. Interconnection techniques well known in the art are utilized to interconnect these elements.
Extending below and connected to perforator assembly 500 is tubing 18. A connector 600 releasably connects the lower end of tubing 18 to a male latch assembly 700. Supported below male latch assembly 700 is seal assembly 800. In the preferred embodiment, seal assembly 800 and male latch assembly 700 have a central passageway 722 (shown in FIG. 5g) providing a fluid passageway therethrough for connection to and fluid communication with well equipment located below seal assembly 800. Male latch assembly 700 fits axially into female latch assembly 400 to structurally connect the latch assemblies together as best illustrated in FIG. 10. Assembly 900 can terminate at the male latch assembly 700. Assembly 900 can comprise any suitable packer closure means such as a removable plug, a valve, a flow control device, a well treatment apparatus, a production assembly, or the like which closes off the packer 200, isolating the well bore 24.
Supported to extend below seal assembly 800 is a suitable tubing 20 connected to production assembly 900 for producing the petrochemicals contained in subterranean formation 16. Production assembly 900 is configured to remain downhole as desired and, for example, may comprise a tail pipe, plug, valve, or the like or a combination thereof. Preferably, assembly 900 has a remotely actuatable valve to stop fluid flow through tubing 20. It is envisioned that other types of equipment could be connected to or carried by seal assembly 800 and substituted for the joint and production assembly where appropriate, such as removable valves, plugs, and the like. For example, a removable plug or remotely actuatable valve could be attached to seal assembly 800 to close the central passageway 722 therein.
In FIG. 1 an initial step of the process of the present invention is shown with the apparatus 8 assembled and lowered into position adjacent to subterranean formation 16. In FIG. 2 actuator 300 has set or expanded packer 200 into a sealing and frictional engagement with interior wall 22 of casing 10 in a manner well known in the art. When set, packer 200 isolates formation 16 from the well fluids located in casing 10 above the packer 200. Once packer 200 is set, perforator assembly 500 is operated to perforate casing 10 and subterranean formation 16 to cause fluid communication.
In accordance with the present invention, running tool 100 is detachably connected to the packer 200 with apparatus discussed later in detail. Running tool 100 can be remotely disconnected therefrom and moved upwardly as shown in FIG. 3. In this step, tubing 14, perforator 500 and tubing 18 are moved axially upward through central passageway 210 defined in packer 200, actuator 300 and female latch assembly 400, as illustrated in FIGS. 5b, 5c and 5d. According to the invention, the elements in isolation apparatus 8 between male latch 700 and female latch 400 are of a diameter sufficient to substantially close central passageway 210 but still axially pass through central passageway 210. The upward or uphole direction of retrieval coupled with the small clearances present in passageway 210 cooperate to substantially prevent if not completely block any passage of well fluids across the packer during the retrieval process. Referring to FIG. 3, as running tool 100 continues upward, male latch assembly 700 lands or axially telescopes into the central passageway of female latch 400. Male latch 700 latches or locks thereto. Seal assembly 800 axially telescopes into the interior of the female latch assembly 400 to mate with suitable seal surfaces in central passageway 210 of female latch assembly 400. When moved into place, assembly 800 seals the annular space between the male and female latches 700 and 400, accordingly.
In FIG. 4 releasable connector 600 is shown after separation from male latch assembly 700. Running tool 100 can be upwardly retrieved or removed from casing 10 with perforator assembly 500 and associated tubing 14 and 16. This step leaves the production packer 200 in place with the production assembly 900 connected thereto for use in well production. As discussed earlier, a valve unit in production assembly 900 selectively prevents fluid flow through production assembly 900.
According to one aspect of the process of the present invention, subterranean formation 16 is selectably isolated from well bore 24 by packer 200 during and following perforation of casing 10 and subterranean formation 16. Damage to subterranean formation 16 otherwise caused by exposure to the well fluids contained above the packer is substantially prevented. In a further step, production tubing can be placed in the well and connected to packer 200 and production assembly 900 to produce oil and gas from subterranean formation 16.
In FIG. 5 (FIGS. 5a through 5h) the details of an exemplary form of an apparatus 8 for use in perforating a well in accordance with the method of the present invention is illustrated. Apparatus 8 as illustrated in FIG. 5 is assembled and ready to be placed in well bore 24 (see FIGS. 1 through 4). The apparatus is shown in a running condition wherein the desired well service operation, such as perforation, can be performed.
Running tool assembly 100 is illustrated in FIGS. 5a and 5b. Running tool assembly 100 has a body 102 and a reducer 104. Both body 102 and reducer 104 are cylindrically shaped and are connected together by mating threads 106. Threads 106 comprise male threads 106a on the lower end of body 102 and female threads 106b on the upper end of reducer 104. Body 102 has a central passageway 108 which is in fluid communication with central passageway 110 formed in reducer 104. Upper end 112 of body 102 is illustrated as a blank for clarity. Upper end 112 can be provided with threads or other suitable coupling means well known in the industry for connecting running tool assembly 100 to running tubing 12 for use in manipulating isolation apparatus 8 into and out of well bore 24. Referring to FIG. 5b, mating threads 114 are provided in the lower end of the reducer 104 to threadedly engage upper end 14a of tubing 14. Mating threads 106 and 114 are locked in a conventional manner to prevent inadvertent disassembly of the connected parts during use downhole.
A conventional production packer 200 is releasably connected to the running tool 100 by mating threads 118. As illustrated in FIG. 5a male threads 118a are formed on the exterior of running tool 100 while mating female threads 118b are formed on the interior of the upper end of production packer 200. Threads 118 merely form a convenient means of releasably connecting production packer 200 to running tool 100 and other means known in the art can be used. Releasing or unscrewing the mating threads 118 allows retrieval of the running tool 100 while production packer 200 is in sealing and frictional engagement with the interior wall 22 of casing 10 as illustrated in FIGS. 2 through 4. It is to be understood that other means well known in the art of releasable connection could be used such as latches, shear pins, or the like. In the present embodiment threads 118 can be disengaged by rotating the running tubing 12 to mechanically separate running tool 100 from production packer 200. It will be appreciated that once the packer 200 is actuated and engaged the casing wall 22, packer 200 is prevented from rotating, allowing separation of running tool 100 therefrom.
In FIG. 5a, the upper end of the production packer assembly 200 is cylindrical in shape and has an interior chamber wall 202. Wall 202 is threaded at an upper end to form the female threads 118b of mating threads 118. Chamber wall 202 forms a cylindrical sealing surface for the seal assembly 116 carried on the exterior of the running tool. Seal assembly 116 comprises resilient elements which seal the annulus between the exterior of the running tool body of 102 and cylindrical interior chamber wall 202. Referring to FIG. 5b, chamber wall 202 extends axially to annular shoulder 206 which separates chamber wall 202 from a reduced diameter chamber wall 208. Walls 202 and 208 define an axially extending central passageway 210 through which tubing 14a extends.
In the illustrated embodiment, packer 200 is of the type which can be actuated to provide a seal in the annulus formed between the interior wall 22 of casing 10 and exterior surface of packer 200. The particular packer illustrated comprises an upper slip assembly 212 positioned above an expandable seal assembly 214. Seal assembly 214 in turn is positioned above a lower slip assembly 216. Slip assembly 212 comprises a plurality of circumferentially-spaced axially-extending slips 218 which are retained axially between shoulder 220 on body 204 and actuator ring 222. Actuator ring 222 is positioned to axially slide along the exterior surface 232 of body 204 and has an annular ramp surface 224. When ring 222 engages slips 218, slips 218 are flared in an outward direction to forcefully engage the surrounding casing wall 22. Lower slip assembly 216 is basically a mirror image of the upper slip assembly 212. Lower slip assembly 216 comprises a plurality of spaced axially extending slips 226 which are contained between actuator ring 228 and ring 230. Rings 228 and 230 are mounted around body 204 to slide axially to outwardly flare the slips 226 in a manner described with regard to slips 218.
Expandable seal assembly 214 is positioned between actuator ring 222 and actuating ring 228. In the embodiment shown, three resilient annular seals 332 are positioned on body 204. It should be noted that the number of seals 332 can vary with respect to the seal material selected and specific downhole environments. When seals 232 are axially compressed between rings 222 and 228 the seals expand to seal the annulus between the body 204 and interior wall 22 of casing 10.
Actuator assembly 300 is shown in FIG. 5b and FIG. 5c. Slip carrier ring 230 of packer assembly 200 is threaded at mating threads 301 to an annular piston 302 of actuator assembly 300. The actuator assembly selected for this embodiment is hydraulically operable. Annular piston 302 slides on the exterior cylindrical surface of body 204. This piston, when moved axially upward along the exterior of the body 204, causes the packer assembly 200 to set as previously described. In addition, a third set of slips or wedges 240 are positioned adjacent actuator ring 228 to lock the slip carrier ring 230 in the actuated position.
As illustrated in FIG. 5c piston 302 is captured between exterior surface 236 of body 204 and interior surface 304 of cylinder assembly 304. Cylinder assembly 304 is connected to the lower end of the body 204 by mating threads 308. Piston 302 is provided with internal and external annular seals 308 and 310, respectively. Internal seals 308 are conventional in design and provide a sliding seal engagement on the exterior surface 236 of body 204. External seals 310 are designed to seal the annulus between the exterior of the piston 302 and interior of the cylinder assembly 304. One or more shear pins 312 initially prevent relative axial movement between piston 302 and cylinder 304. Radially extending ports 314 in body 204 provide fluid communication between variable volume actuator chamber 316 and central passageway 210.
As shown in FIG. 5c the lower end of cylinder assembly 304 is connected to the upper end of female latch assembly 400 by threads 322. Female latch assembly 400 has an upper and lower cylindrical seal housing 402 and 404, respectively. Housing 402 has a cylindrical interior wall 406 forming cylindrical seal surface 408. Seal surface 408 is slightly reduced in diameter as compared to the adjacent interior wall 406 defining central passageway 210.
A seal subassembly 330 is connected to the lower end of tubing 14a by mating threads 338. Seal subassembly 330 has a plurality of ports 336 which communicate with the interior cavity 26 of tubing 14a. Outer surface 340 of seal assembly 330 defines grooves 312 which carries a plurality of annular seals 334. Seals 334 can be O-rings, packing, or the like. Seals 334 are selected to be of a size to mate with the seal surface 408 of upper seal housing 402 to seal the annulus between the exterior surface 340 of seal subassembly 330 and the interior of upper seal housing 402.
The lower end 330b of seal subassembly 330 is connected by threads 338 to tubing 14b. Tubing 14b is selected to be of a sufficient length to extend completely through and below female latch assembly 400. The lower extending end of tubing 14b is connected to and supports the perforator assembly 500, as will be described hereinafter.
It is to be noted that when isolation apparatus is in the running position as illustrated in FIG. 5 the annular seals 334 seal the lower end of central passageway 210 (see FIG. 5c) while seal assembly 116 seals the upper end thereof (see FIG. 5a). A plurality of radially extending ports 336 are formed in seal subassembly 330 to provide fluid communication between the interior cavity 26 of tubing 14a and central passageway 210. Ports 336 are used to remotely operate actuator assembly 300 to set packer 200.
Setting packer 200 is accomplished by increasing the pressure within the tubing 14a which is communicated through ports 336 to central passageway 210. Central passageway 210 is in fluid communication with variable volume chamber 316 through ports 314. As the pressure within the tubing 14a is increased, pressure in variable volume chamber 316 is likewise increased, applying a force to bottom 326 of annular piston 302 to hydraulically actuate the piston. Reacting to the hydraulic pressure present in variable volume chamber 316, piston 302 is urged in an upward direction with respect to cylinder 304. Pins 312 are manufactured and mounted in an engineered configuration to shear at a predetermined pressure present in variable volume chamber 316, allowing piston 302 to reciprocate with respect to cylinder 304 to actuate and set packer assembly 200.
In FIG. 5d, seal housings 402 and 404 are shown connected together by mating threads 410. To prevent inadvertent separation, a plurality of radially extending set screws or pins 412 lock the threads 410 in an assembled position. A plurality of annular seals 414 seal the joint between seal housings 402 and 404. Lower end 416 of lower cylindrical seal housing 404 is open and has a frustoconical guide surface at shoulder 418 formed therein. The interior of end 416 forms an axially ending cylindrical sealing surface 420.
Latch element 422 is located in the interior of female latch assembly 400 at the juncture of the upper and lower cylindrical seal housings 402 and 404. Details of the structure of the latch element 422 and its mounting within the female latch assembly 400 will be described by reference to the FIGS. 6, 7, and 8.
In FIG. 6 the juncture between the upper and lower cylindrical seal housings 402 and 404 is shown the latch element 422 removed for clarity. The cylindrical inner wall 424 has a diameter which approximates the cylindrical sealing surface 420 in housing 404. Extending axially from and concentrically with cylindrical inner wall 424 is an enlarged diameter cylindrical recess 426. A second larger cylindrical recess 428 adjoins recess 426 and extends to the lower end 430 of housing 402. Recess 428 is cylindrical in shape and coaxial with recess 426 and slightly larger in diameter than recess 426. A recess 432 is formed in lower cylindrical seal housing 404 adjacent to sealing surface 420. Recess 432 is coaxial with surface 420 and is preferably selected to be of the same diameter as recess 426. A second recess 434 is formed in housing 404 and is located between recess 432 and shoulder 436 on housing 404. Recess 434 is coaxial with recess 432 and is preferably selected to be of the same diameter as the second recess 428 in upper seal housing 402.
In FIG. 7 latch element 422 is shown positioned within female latch assembly 400. Latch element 422 is a cylindrical member with a wall thickness substantially approximating the radial depth of recess 426 in upper housing 402 and recess 432 in lower housing 404. Interior wall 438 of latch element 422 has an internal diameter which substantially approximates the diameter of sealing surfaces 420 and 424. The outer diameter of latch element 422 is slightly smaller than the internal diameter of recesses 426 and 432 such that latch element 422 can slide relatively freely in an axial direction within the confines of the recesses 426 and 432. As is shown in FIG. 7, shoulder 440 defines the upper axial boundary of recess 426 while shoulder 440 defines the lower axial boundary of recess 432.
According to the features of the present invention latch element 422 has an effective axial length represented by dimension "A" which is less than the axial length between shoulders 440 and 442 represented by dimension "B." Latch element 422 can slide axially between shoulders 440 and 442 in the forward and reverse direction of arrow "C."
As illustrated in FIG. 7, latch element 422 has a plurality of axially extending slots 444 formed therein. Slots 444 are circumferentially spaced to extend through the wall of the latch element 422. A plurality of ratchet teeth 446 are formed on interior wall 438 of latch element 422. These ratchet teeth can be in the form of dogs or thread-like extensions from the surface of latch element 422. It is noted that the ratchet teeth 446 are located in the spring arms 448 between the slots 444. It is preferable that the latch element 422 be made of spring-like metallic material which can be deflected radially outward without permanent deformation.
When latch element 422 is in the position shown in FIG. 7 (or moved further in the direction of arrow "C" to a point where latch element 422 abuts shoulder 440) spring arms 448 are adjacent to recesses 428 and 434. In this position, the spring arms 448 can be deflected outward into the annular clearance defined between exterior surface 452 of latch element 422 and recesses 428 and 434, respectively.
In FIG. 8 the latch element 422 is shown axially moved in a reverse direction of arrow "C" to abut shoulder 440. In this position the ratchet teeth 446 on spring arms 448 cannot deflect outward because of the close confines of the recess 432. That is, when ratchet teeth 446 are axially aligned with the enlarged diameter area formed by recesses 428 and 434, spring arms 448 can deflect outward into the annular clearance. When ratchet teeth 446 move adjacent to recess 432, the close proximity of the outer diameter of the latch element 422 and the inner diameter of the recess 432 prevents outward deflection of spring arms 448. As will be described in detail hereinafter, the axial movement of the ratchet teeth 446 into and out of the enlarged diameter recesses 428 and 434 is utilized to perform a latching function during removal of running tool 100, perforator assembly 500, and associated tubing 14 and 16.
Referring now to FIG. 5e, it can be seen that the lower end 14b of tubing 14 which extends through and below the female latch assembly 400 (see FIG. 5d) is connected by a suitable collar 502 to perforator assembly 500. Perforator assembly 500 is of the type which is commercially available in the industry and which can be remotely actuated once in proper position. Perforator assembly 500 has an actuator 504 and a gun 506. Perforator assembly 500 is selected for the particular application and can be used to perforate casing 10 and subterranean formation 16 where desired after the packer assembly 200 has been set.
As shown in FIG. 5f a sleeve 508 connects the lower end of perforator 500 to the upper end 16a of tubing 16. Referring to FIG. 5g, tubing 16 is coupled at its lower end 16b through a releasable connector 600 to the upper end of the male latch assembly 700. The lower end of male latch assembly 700 is in turn connected to seal assembly 800.
In the embodiment shown in FIG. 5g, releasable connector 600 is threaded at mating threads 602 to lower end 16b of tubing 16. The lower end of releasable connector 600 is necked down to form a cylindrical male end 604. Male end 604 telescopes into the upper end of male latch assembly 700 and is connected thereto by a plurality of shear pins 606. During retrieval of perforator assembly 500 and associated equipment, shear pins 606 are sheared to separate connector 600 from the upper end of male latch assembly 700.
Male latch assembly 700 mates or engages with female latch assembly 400. In this regard the male latch assembly 700 has a plurality of circumferentially-extending, axially-spaced ratchet teeth 702 formed on the exterior thereof. Ratchet teeth 702 are selected to be of a size to mate with and engage ratchet teeth 446 of latch element 422 contained in female latch assembly 400. Ratchet teeth 700 are biased in a downward direction while ratchet teeth 446 are biased in an upward direction. The effective diameters of the teeth 446 and 700 are selected to provide an interlocking function that will be described later in detail.
Cylindrical housing 704 is reduced in diameter at its lower end 706 to receive a plurality of cylindrical packing elements 802 of the seal assembly 800. Packing elements 802 are selected to be of a size to mate with and seal with sealing surface 420 of the female latch assembly 400. Packing elements 802 are of a conventional design well known in the industry. The lower end of reduced portion 706 is threaded at mating threads 708 to collar 710. Radially extending circumferentially-spaced flutes 712 are formed on the lower end of collar 710.
According to a particular feature of the present invention, the outside diameter of the collar 600 illustrated in FIG. 5g is slightly smaller in diameter than the central passageway 210 (see FIGS. 5a through 5d) which extend through packer assembly 200, actuator 300, and female latch assembly 400. Once shear pins 606 are sheared collar 600 can be removed from the well bore 24 via central passageway 210. Additionally, the external diameter of male latch assembly 700 and seal assembly 800 is selected to land or lock with the interior of the female latch assembly 400 when axially moved upward in the direction of "C." Flutes 712 on collar 710 are slightly larger in external diameter than cylindrical seal surface 420 in female latch assembly 400. It will be appreciated that flutes 712 contact shoulder 418 on the lower end of the female latch assembly 400 to prevent further upward movement of the male latch assembly 700 into the female latch assembly. Any continued upward force is then transferred to shear pins 606 which sever when sufficient upward force is applied, causing connector 600 to release male latch assembly 700.
In FIG. 5h, collar 714 connects the lower end of collar 710 to tubing 20. Tubing 20 is of a length to place production assembly 900 at a desirable distance below packer 200 when male latch assembly 700 and female latch assembly 400 are in an engaged relation (see FIGS. 9 and 10). Production assembly 900 can be of any conventional design well known in the industry. Production assembly 900 can, for example, preferably have remotely-actuatable valve 902, perforated joint 903 and landing nipple 904. Valve 902 can be conventional in design and can, for example, be retrievable. A primary consideration of selecting valve 902 is that it can temporarily terminate the lower end of the tubing during the activation of perforator assembly and then be opened for well production.
Details of the interaction of male latch assembly 700 and female latch assembly 400 during the latching and retrieving steps shown in FIGS. 3 and 4 will be explained with reference to FIGS. 9 and 10. The sequence illustrated in FIG. 9 is present after perforation has been completed through casing 10 and subterranean formation 16 and after running tool 100 has been disconnected from packer 200. As discussed earlier, the diameter of perforation assembly 500 is such that it also has been removed through packer 200 and female latch assembly 400 via central passageway 210. FIG. 9 shows the occurrence of two further steps. First, flutes 712 engage shoulder 418 preventing further upward movement of the tubing 18 into female latch assembly 400. Second, ratchet teeth 702, because of the interference fit with ratchet teeth 446, causing latch element 422 to be moved axially upward within recesses 426 and 432. Upward movement of latch element 422 continues until shoulder 440 is engaged. Once shoulder 440 is engaged by latch element 422, ratchet teeth 702 impart an axially force against spring arms 448, causing spring arms 448 to deflect outward into the annular clearance defined between exterior surface 452 of latch element 422 and recesses 428 and 434, respectively. The deflection allows ratchet teeth 702 to slide upward with respect to ratchet teeth 446.
As illustrated in FIG. 9, the relative axial position of the recesses, ratchet teeth, and shoulder 440 are such that ratchet teeth 702 and 446 are engaged when further upward movement of tubing 18 is prevented by engagement of flutes 712 with shoulder 418. At this limit of upward movement, a jar or other upward force can be applied to tubing 16 sufficient to shear the pins 606, disengaging connector 600 from male latch assembly 700.
The effect of the sheared separation is illustrated in FIG. 10. As shown, once pins 606 are sheared, collar 600 and tubing 18 are free to move in the upward direction to be completely retrieved from the well bore 24. With respect to the present embodiment, perforation assembly 500 is retrieved along with collar 600 and tubing. As pins 606 are sheared, the weight of the elements suspended from male latch assembly 700 forces male latch 700 in the reverse direction of arrow "C." The interference or ratchet engagement of ratchet teeth 702 of male latch assembly 700 with ratchet teeth 446 of female latch assembly 400 cause latch element 422 to slide in a downward direction to engage shoulder 442. Such engagement by latch element 422 shown in FIG. 10 is that previously described with reference to FIG. 8.
In this position, ratchet teeth 446 have moved axially downward past the annular clearance defined between exterior surface 452 of latch element 422 and recesses 428 and 434, respectively. Outward radial deflection of spring arms 448 is prevented by recess 432, effectively locking ratchet teeth 702 and ratchet teeth 446 together to complete the latching operation.
These latching-separation steps described with reference to FIGS. 9 and 10 allows removal of unnecessary downhole-tooling assemblies while leaving a production assembly 900 supported below a packer which is sealed off by the engagement of seal assembly 800 with sealing surface 420. It should be noted that although the ratchet-type latch is advantageous in such applications, it is appreciated that connecting could be accomplished by other techniques such as by threading, J-slots, or the like.
The embodiment shown and described above is only exemplary. Many details which are omitted are well known in the art such as descriptions of the inner workings of perforator guns, remotely actuatable production valves, pinning nipples, and the like. Therefore, many such details are neither shown or described. It is not claimed that all the details, parts, elements, or steps described and shown were invented herein. Even though numerous characteristics and advantages of the present inventions have been set forth in the foregoing description, together with the details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in the detail, especially in the matters of shape, size, and arrangement of the parts within the principles of the inventions to the full extent indicated by the broad general meaning of the terms used in the attached claims. The restrictive description and drawings of the specific examples do not point out what an infringement of this patent would be, but are to provide at least one explanation how to make and use the inventions. The limits of the inventions and the bounds of the patent protection are measured by and defined by the following claims. | Disclosed is an improved apparatus and method for performing downhole operations to a subterranean formation while isolating the formation from the remainder of the well bore. The invention utilizes a tool assembly which initially sets a packer above the formation while allowing a downhole tool to extend through a passageway in the packer to perform operations such as perforating the formation. The assembly permits retrieval of the tools through the passageway in the packer while sealing off the formation from the remainder of the well. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority of provisional application Ser. No. 61/002,978 and Ser. No. 60/987,647, both of which were filed on Nov. 13, 2007, and whose disclosures are incorporated by reference.
GOVERNMENTAL SUPPORT
The present invention was made with governmental support under Contract No. CA041986 awarded by the National Institutes of Health. The government has certain rights in the invention.
FIELD OF INVENTION
The invention relates to prodrug anticancer agents and to their use. More particularly, the invention relates to N-acyl O-amino phenol prodrugs of CBI-TMI and CBI-indole 2 .
BACKGROUND
CC-1065, the duocarmycins, and yatakemycin constitute exceptionally potent naturally occurring antitumor agents that derive their biological properties through a characteristic sequence-selective DNA alkylation reaction (below) (Chidester, C. G.; et al. J. Am. Chem. Soc. 1981, 103, 7629; Trzupek, J. D.; et al. Nature Chem. Biol. 2006, 2, 79).
The examination of the natural products, their synthetic unnatural enantiomers, their derivatives, and synthetic analogues have defined fundamental features that control the alkylation selectivity, impact the alkylation efficiency, and are responsible for DNA alkylation catalysis providing a detailed understanding of the relationships between structure, reactivity, and biological activity (Warpehoski, M. A.; Hurley, L. H. Chem. Res. Toxicol. 1988, 1, 315; Boger, D. L. Chem. Biol. 2004, 11, 1607.).
One of the most important and widely explored class of analogues is CBI (Boger, D. L.; et al. J. Am. Chem. Soc. 1989, 111, 6461; Boger, D. L.; et al. J. Org. Chem. 1990, 55, 5823) (1,2,9,9a-tetrahydrocyclopropa[c]benz[e]indol-4-one), being synthetically (Boger, D. L.; et al. J. Am. Chem. Soc. 1989, 111, 6461; Boger, D. L.; et al. J. Org. Chem. 1990, 55, 5823; Boger, D. L.; et al. J. Org. Chem. 1992, 57, 2873; Boger, D. L.; McKie, J. A. J. Org. Chem. 1995, 60, 1271; Drost, K. J.; Cava, M. P. J. Org. Chem. 1991, 56, 2240; Aristoff, P. A.; Johnson, P. D. J. Org. Chem. 1992, 57, 6234; Mohamadi, F.; et al. J. Med. Chem. 1994, 37, 232; Ling, L.; et al. Heterocyclic Commun. 1997, 3, 405; Boger, D. L.; et al. Synlett 1997, 515; Boger, D. L.; et al. Tetrahedron Lett. 1998, 39, 2227; Kastrinsky, D. B.; Boger, D. L. J. Org. Chem. 2004, 69, 2284) more accessible than the natural products, yet indistinguishable in their DNA alkylation selectivity (FIG. 2) (Boger, D. L.; Munk, S. A. J. Am. Chem. Soc. 1992, 114, 5487).
Moreover, the CBI derivatives proved to be four times more stable and, correspondingly, four times more potent than derivatives bearing the CC-1065 alkylation subunit (7-MeCPI) approaching the stability and potency of duocarmycin SA and yatakemycin derivatives, and they exhibit efficacious in vivo antitumor activity in animal models at doses that reflect this potency (Boger, D. L.; et al. Bioorg. Med. Chem. Lett. 1991, 1, 115; Boger, D. L.; et al. Bioorg. Med. Chem. 1995, 3, 1429). Consequently, CBI and its derivatives have been the focus of much development as well as the prototype analogues on which new design concepts have been explored, developed, or introduced (Boger, D. L.; et al. J. Am. Chem. Soc. 1989, 111, 6461; Tietze, L. F.; et al. Angew. Chem. Int. Ed. 2006, 45, 6574; Wang, Y.; et al. Bioorg. Med. Chem. 2003, 11, 1569; Jeffrey, S. C.; et al. J. Med. Chem. 2005, 48, 1344; Kline, T.; et al. Mol. Pharmaceut. 2004, 1, 9; Hay, M. P.; et al. J. Med. Chem. 2003, 46, 5533; Tercel, M.; et al. J. Med. Chem. 2003, 46, 2132; Gieseg, M. A.; et al. Anti - Cancer Drug Design 1999, 14, 77; Hay, M. P.; et al. Bioorg. Med. Chem. Lett. 1999, 9, 2237; Atwell, G. J.; et al. J. Med. Chem. 1999, 42, 3400; Atwell, G. J.; et al. J. Org. Chem. 1998, 63, 9414; Atwell, G. J.; et al. Bioorg. Med. Chem. Lett. 1997, 7, 1493; Townes, H.; et al. Med. Chem. Res. 2002, 11, 248; Boger, D. L.; Garbaccio, R. M. J. Org. Chem. 1999, 69, 8350).
A unique feature of this class of molecules including the natural products themselves is the observation that synthetic phenol precursors (e.g., 1) to the final products, entailing a Winstein Ar-3′ spirocyclization with displacement of an appropriate leaving group, exhibit biological properties typically indistinguishable from the cyclopropane-containing final products (DNA alkylation rate or efficiency, in vitro cytotoxic activity, and in vivo antitumor activity). This dependable behavior of the precursor phenols has provided the basis on which the development of useful, stable, or safe prodrugs has been conducted (Carzelesin: Aristoff, P. A. Adv. Med. Chem. 1993, 2, 67. KW-2189: Kobayashi, E.; et al. Cancer Res. 1994, 54, 2404; Amishiro, N.; et al. Bioorg. Med. Chem. 2000, 8, 1637; Amishiro, N.; et al. J. Med. Chem. 1999, 42, 669; Nagamura, S.; et al. Chem. Pharm. Bull. 1996, 44, 1723; Nagamura, S.; et al. Chem. Pharm. Bull. 1995, 43. CBI: Boger, D. L.; et al. Synthesis 1999, 1505).
One feature limiting the attractiveness of this class of cytotoxic agents is their remarkable potencies (IC 50 5-20 pM) creating special requirements for their preparation and handling. In many instances, this has been addressed by the introduction of chemically stable phenol protecting groups that are readily cleaved at the final stage of their preparation or upon in vivo administration. Such protected phenol precursors are intrinsically much less potent, yet readily release an active precursor to the drug upon deprotection. Extensions of this protection and release strategy have been pursued in which the free phenol release in vivo is coupled to features that might facilitate tumor selective delivery or cleavage (Wolkenberg, S. E.; Boger, D. L. Chem. Rev. 2002, 102, 2477. Reviews on reductive activation: Papadopoulou, M. V.; Bloomer, W. D. Drugs Future 2004, 29, 807; Jaffar, M.; Stratford, I. J. Exp. Opin. Ther. Patents 1999, 9, 1371; Patterson, L. H.; Raleigh, S. M. Biomed. Health Res. 1998, 25, 72). Such inactive prodrugs serve the dual role of providing safer handling intermediates or final products as well as potentially enhancing the therapeutic index of the drug.
As attractive and amenable as this approach is for this class of drugs, a surprisingly small series of such studies have been disclosed (Chari, R. V. J.; et al. Cancer Res. 1995, 55, 4079; Lillo, A. M.; et al. Chem. Biol. 2004, 11, 897; Tietze, L. F.; et al. Eur. J. Org. Chem. 2002, 10, 1634; Tietze, L. F.; et al. Angew. Chem. Int. Ed. 2002, 41, 759; Tietze, L. F.; et al. ChemBioChem 2001, 2, 758; Tietze, L. F.; et al. Angew. Chem. Int. Ed. 2006, 45, 6574; Wang, Y.; et al. Bioorg. Med. Chem. 2003, 11, 1569; Jeffrey, S. C.; et al. J. Med. Chem. 2005, 48, 1344; Kline, T.; et al. Mol. Pharmaceut. 2004, 1, 9; Hay, M. P.; et al. J. Med. Chem. 2003, 46, 5533; Tercel, M.; et al. J. Med. Chem. 2003, 46, 2132; Gieseg, M. A.; et al. Anti - Cancer Drug Design 1999, 14, 77; Hay, M. P.; et al. Bioorg. Med. Chem. Lett. 1999, 9, 2237; Atwell, G. J.; et al. J. Med. Chem. 1999, 42, 3400; Atwell, G. J.; et al. J. Org. Chem. 1998, 63, 9414; Atwell, G. J.; et al. Bioorg. Med. Chem. Lett. 1997, 7, 1493; Townes, H.; et al. Med. Chem. Res. 2002, 11, 248; Boger, D. L.; Garbaccio, R. M. J. Org. Chem. 1999, 69, 8350).
BRIEF SUMMARY OF THE INVENTION
N-Acyl O-amino phenol derivatives of CBI-TMI and CBI-indole 2 are disclosed herein as prototypical members of a new class of reductively activated prodrugs of the duocarmycin and CC-1065 class of antitumor agents. The expectation being that hypoxic tumor environments, with their higher reducing capacity, carry an intrinsic higher concentration of “reducing” nucleophiles (e.g., thiols) capable of activating such derivatives (tunable N—O bond cleavage) increasing their sensitivity to the prodrug treatment. Preliminary studies indicate the prodrugs effectively release the free drug in functional cellular assays for cytotoxic activity approaching or matching the activity of the free drug, yet remain essentially stable and unreactive to in vitro DNA alkylation conditions (<0.1-0.01% free drug release), pH 7.0 phosphate buffer, and exhibit a robust half-life in human plasma (t 1/2 =3 hours). Characterization of a representative O-(acylamino) prodrug in vivo indicates that they approach the potency and exceed the efficacy of the free drug itself (CBI-indole 2 ) indicating that not only is the free drug effectively released from the inactive prodrug, but that they offer additional advantages related to a controlled or targeted release in vivo.
A contemplated compound of the invention is an N-acyl O-amino CBI derivative that is represented by Formula I:
In Formula I, R 1 is selected from the group of radicals consisting of —C(O)(C 1 -C 6 alkyl), —C(O)O(C 1 -C 10 alkyl), —C(O)(C 2 -C 6 alkenyl), —C(O)O(C 2 -C 6 alkenyl), and —C(O)aryl. R 2 is selected from the group of radicals consisting of hydrogen, —C(O)(C 1 -C 6 alkyl), —C(O)O(C 1 -C 10 alkyl), —C(O)(C 2 -C 6 alkenyl), and —C(O)O(C 2 -C 6 alkenyl). In the alternative, R 1 and R 2 are combined to form a cyclic structure selected from the group consisting of divalent radicals represented as follows:
R 3 in Formula I is selected from group consisting of radicals represented as follows:
wherein R 4 is selected from group consisting of radicals represented as follows:
R 5 , R 6 , R 7 and R 8 in the above structural formulas are each independently selected from the group of radicals consisting of —H, —OH, —O(C 1 -C 6 alkyl), —(C 1 -C 6 alkyl) and halogen. R 9 of an above formula is selected from the group of radicals consisting of —H, —C(O)O(C 1 -C 6 alkyl), —C(O)(C 1 -C 6 alkyl), —C(O)NH 2 , —C(O)NHNH 2 , and —C(O)NHNHC(O)O(C 1 -C 6 alkyl).
In a preferred compound, R 4 is selected from the group of radicals consisting of —C(O)(C 1 -C 6 alkyl) and —C(O)O(C 1 -C 10 alkyl); R 2 is selected from the group of radicals consisting of hydrogen (hydrido; —H), —C(O)(C 1 -C 6 alkyl), and —C(O)O(C 1 -C 10 alkyl); or, alternatively, R 4 and R 2 combine to form a cyclic divalent radical represented by the following structure (phthalyl):
R 3 is selected from the group consisting of the following radicals:
wherein:
R 4 is
Particularly preferred compounds include those with the following structural formulas:
A process for treating a proliferative disease such as a cancer or leukemia in a mammal is also contemplated. In accordance with that process, an effective amount of a compound of Formula I such as one of the five compounds shown immediately above is administered to a mammal in need thereof. In yet another aspect, the use of a compound of Formula I in the manufacture of a medicament for treating a proliferative disease such as cancer or leukemia is contemplated.
It is noted that in the structural formulas utilized herein that a wavy line indicates a chemical bond to a depicted atom. It is also noted that to improve readability and minimize seeming duplication, any combination of structural elements described broadly can be present in a specific embodiment unless otherwise stated.
BRIEF DESCRIPTION OF DRAWINGS
In the drawings forming a portion of this disclosure,
FIG. 1 illustrates the results of an electrophoresis gel with 8% denaturing PAGE and autoradiography. Thermally-induced strand cleavage of w794 DNA; DNA-agent incubation at 4° C. for 18 hours, removal of unbound agent by EtOH precipitation, and 30 minutes of thermolysis (100° C.) followed by 8% denaturing PAGE and autoradiography. Lane 1, control DNA; lanes 2-5, Sanger G, C, A, and T sequencing reactions; lanes 6-8, 2 (1×10 −4 to 1×10 −6 ); lanes 9-11, 10 (1×10 −1 to 1×10 −3 ); lanes 12-14, 4 (1×10 −1 to 1×10 −3 ), lanes 15-17, 9 (1×10 −1 to 1×10 −3 ). All compounds possess the natural 1S-configuration. The reductively activated agent 4 was found to alkylate w794 DNA with an identical sequence selectivity as the parent agent CBI-TMI (2), albeit with a substantially reduced efficiency (1,000-10,000-fold). Similarly, the O-methyl ether 10 as well as 9 lacking a C4 substituent failed to exhibit significant observable DNA alkylation.
DETAILED DESCRIPTION OF THE INVENTION
A novel set of reductively activated phenol prodrugs of the CC-1065 and duocarmycin class of compounds is disclosed. These compounds do not require enzymatic release and are illustrative of other phenolic drugs that can benefit from such a designed activation. Alternative and prior efforts at incorporating a reductive activation into the CC-1065 and duocarmycin class includes the Denny disclosures of nitro precursors to aryl amine variants of the phenol precursors (Hay, M. P.; et al. J. Med. Chem. 2003, 46, 5533; Tercel, M.; et al. J. Med. Chem. 2003, 46, 2132; Gieseg, M. A.; et al. Anti - Cancer Drug Design 1999, 14, 77; Hay, M. P.; et al. Bioorg. Med. Chem. Lett. 1999, 9, 2237; Atwell, G. J.; et al. J. Med. Chem. 1999, 42, 3400; Atwell, G. J.; et al. J. Org. Chem. 1998, 63, 9414; Atwell, G. J.; et al. Bioorg. Med. Chem. Lett. 1997, 7, 1493), Lee's use of an ester subject to cleavage upon a tethered quinone reduction (Townes, H.; et al. Med. Chem. Res. 2002, 11, 248), and a report of mitomycin-like quinone precursors to a reductively activated o-spirocyclization (versus p-spirocyclization) analogous to those observed with the duocarmycins or its analogues (Boger, D. L.; Garbaccio, R. M. J. Org. Chem. 1999, 69, 8350).
Although the approaches have provided some increase in selectivity resulting from reductive activation, none approach that observed with mitomycin and none effectively or clearly utilize an intrinsic enzyme activity that differentiated normal versus tumor cells. Notably, it may be the ease of the mitomycin hydroquinone reoxidation to the quinone in normal cells that protects them from the effects of the drug, which occurs less readily in hypoxic tumors.
The structure of CBI (1,2,9,9a-tetrahydrocyclopropa[c]benz[e]indol-4-one) and its precursor 1 where R is just the DNA binding portion of the molecule along with its precursor, the O-amino phenol derivative or prodrug that requires reductive activation by N—O bond cleavage are shown below. The CBI compounds are more accessible than the natural products, yet indistinguishable in their DNA alkylation selectivity (Boger, D. L.; Munk, S. A. J. Am. Chem. Soc. 1992, 114, 5487). Moreover, the CBI derivatives proved to be four times more stable and, correspondingly, four times more potent than derivatives bearing the CC-1065 alkylation subunit (7-MeCPI) approaching the stability and potency of duocarmycin SA and yatakemycin derivatives, and they exhibit efficacious in vivo antitumor activity in animal models at doses that reflect this potency. Consequently, CBI and its derivatives have been the focus of much development as well as the prototype analogues on which new design concepts have been explored, developed, or introduced, including the instant invention.
The approach detailed herein was not designed for enzymatic reductive activation, but rather for activation by cleavage of a weak N—O bond by reducing nucleophiles. The expectation of this approach being that hypoxic tumor cells, with their higher reducing capacity, contain an intrinsically higher concentration of “reducing” nucleophiles (i.e., thiols) capable of activating such derivatives making them more sensitive to the prodrug treatment (Wolkenberg, S. E.; Boger, D. L. Chem. Rev. 2002, 102, 2477. Reviews on reductive activation: Papadopoulou, M. V.; Bloomer, W. D. Drugs Future 2004, 29, 807; Jaffar, M.; Stratford, I. J. Exp. Opin. Ther. Patents 1999, 9, 1371; Patterson, L. H.; Raleigh, S. M. Biomed. Health Res. 1998, 25, 72). Moreover, as detailed below, the design lends itself to a rational tuning of the ease of reduction of the derivative allowing empirical experience with the series to guide future design.
A contemplated compound of the invention is an N-acyl O-amino CBI derivative that is represented by Formula I:
In Formula I, R 4 is selected from the group of radicals consisting of —C(O)(C 1 -C 6 alkyl), —C(O)O(C 1 -C 10 alkyl), —C(O)(C 2 -C 6 alkenyl), —C(O)O(C 2 -C 6 alkenyl), and —C(O)aryl. R 2 is selected from the group of radicals consisting of hydrogen, —C(O)(C 1 -C 6 alkyl), —C(O)O(C 1 -C 10 alkyl), —C(O)(C 2 -C 6 alkenyl), and —C(O)O(C 2 -C 6 alkenyl). In the alternative, R 4 and R 2 are combined to form a cyclic structure selected from the group consisting of divalent radicals represented as follows:
R 3 in Formula I is selected from group consisting of radicals represented as follows:
wherein R 4 is selected from group consisting of radicals represented as follows:
R 5 , R 6 , R 7 and R 8 in the above structural formulas are each independently selected from the group of radicals consisting of —H, —OH, —O(C 1 -C 6 alkyl), —(C 1 -C 6 alkyl) and halogen. R 9 of an above formula is selected from the group of radicals consisting of —H, —C(O)O(C 1 -C 6 alkyl), —C(O)(C 1 -C 6 alkyl), —C(O)NH 2 , —C(O)NHNH 2 , and —C(O)NHNHC(O)O(C 1 -C 6 alkyl).
In any of the Formulas herein, the term “C 1 -C 6 alkyl” denotes a straight or branched chain radical such as a methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, amyl, tert-amyl, hexyl group and the like.
The term “C 2 -C 6 alkenyl” denotes a radical such as a vinyl, allyl, 2-butenyl, 3-butenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl group and the like, as well as dienes and trienes of straight and branched chains containing up to six carbon atoms and at least one carbon-to-carbon (ethylenic) double bond.
The term “halogen” includes fluoro, chloro, bromo and iodo, with chloro being preferred.
The term “aryl” is meant to include a monocyclic or dicyclic aromatic radical containing 5 to 10 atoms in the ring system and zero, one or three atoms other than carbon in the rings. The atoms other than carbon can be selected from oxygen, nitrogen and sulfur. Illustrative aryl radicals include phenyl, 1- and 2-naphthyl, pyridyl, pyrazinyl, pyrimidyl, imidazyl, thiophenyl, furanyl, pyrrolyl, 1,3,5-triaziyl, 1,2,4-triazinyl and 1,2,3-triazinyl, quinazolinyl, quinolinyl, their various positional isomers, and the like.
Pharmaceutical Compositions and Treatment Methods
A Pharmaceutical Composition for Treating
A process for treating a proliferative disease such as a cancer or leukemia in a mammal is also contemplated. Such a composition contains a pharmaceutically effective amount of a before-discussed molecule of Formula I dissolved or dispersed in a pharmaceutically acceptable diluent.
A contemplated compound of Formula I can be used in a pharmaceutical composition to treat and preferably kill cancer cells or cells of another proliferative disease such as leukemia in vitro or in vivo in a mammalian subject. Thus, an above composition is contacted with the cells to be treated. The cells so treated are maintained in contact with a compound of Formula I until cleared by the body when in vivo, or for various times as desired in an in vitro study. The treatment is generally repeated several times.
A mammal to which or whom a compound of Formula I composition is administered can be a primate such as a human, an ape such as a chimpanzee or gorilla, a monkey such as a cynomolgus monkey or a macaque, a laboratory animal such as a rat, mouse or rabbit, a companion animal such as a dog, cat, horse, or a food animal such as a cow or steer, sheep, lamb, pig, goat, llama or the like in need of treatment for a cancerous condition.
A contemplated composition is administered to a mammal in need of the medication at an proliferative effective dosage level. That level is typically an amount sufficient to provide about 10 to about 100 μg/kg of body weight to the recipient's plasma or serum, using the molecular weight of the scission-activated duocarmycin-type prodrug Compound 8 itself as the basis for calculation in view of the
different molecular weights of the other prodrug compounds contemplated herein. The amount can vary depending on the recipient and proliferative cell load. Those plasma or serum concentrations can usually be obtained by i.v. administration using a liquid dosage form that contains about 200 mg to about 1000 mg of chimer compound per day. The determination of optimum dosages for a particular situation is within the skill of the art.
A compound of Formula I composition is administered repeatedly, on a schedule adapted for a recipient's cancer load and need, as is well known in the art. Typical administrations are given multiple times within a one month time period, usually followed by a rest period and then further administrations and rest periods until the recipient is free of the disease, or longer for prophylactic purposes.
For preparing pharmaceutical compositions containing a chimer compound of the invention, an inert, pharmaceutically acceptable carrier or diluent is used. The diluent is usually in liquid form.
Liquid pharmaceutical compositions include, for example, solutions suitable for parenteral administration. Sterile water solutions of the active chimer or sterile solutions of the active component in solvents comprising water, ethanol, or propylene glycol are examples of liquid compositions suitable for parenteral administration.
Sterile solutions can be prepared by dissolving the active component in the desired solvent system, and then passing the resulting solution through a membrane filter to sterilize it or, alternatively, by dissolving the sterile compound in a previously sterilized solvent under sterile conditions.
Preferably, the pharmaceutical composition is in unit dosage form. In such form, the composition is divided into unit doses containing appropriate quantities of the active urea. The unit dosage form can be a packaged preparation, the package containing discrete quantities of the preparation, for example, in vials or ampules.
Chemistry
Synthesis
A range of methods for direct conversion of a precursor phenol to the corresponding O-amino phenol were examined (O-amidation) and several routes to the final compounds were explored. It was anticipated that this might best be conducted on a seco-N-Boc-CBI derivative lacking the capabilities of spirocyclization (e.g., 11). However, the lability of the resulting N-acyl O-amino phenol derivatives to subsequent chemical transformations proved significant and this approach proved less viable than a surprisingly effective direct O-amidation reaction of seco-CBI-TMI or seco-CBI-indole 2 .
Schemes 1A and 1B, below, show the synthesis of the N-acyl O-amino phenols directly from the precursors 2 and 3. Thus, low temperature phenol deprotonation of 2 (3 equiv of LiHMDS, 0° C., ether-dioxane) followed by treatment with the amidating reagents TsONHBoc (Greck, C.; et al. Bull. Soc. Chim. Fr. 1994, 131, 429) or TsONPhth (Neumann, U.; Gütschow, M. J. Biol. Chem. 1994, 269, 21561) provided 4 and 8 directly in good conversions. Competitive spirocyclization of 2 to CBI-TMI itself was observed if the deprotonation was carried out at higher reaction temperatures or in more polar solvents. It diminished as the solvent polarity was reduced (glyme>THF>dioxane-ether>ether, insoluble) and was less prominent with LiHMDS versus NaHMDS.
In most instances, recovered starting phenol was present in the crude reaction product and was chromatographically close enough to the N-acyl O-amino phenols that special precautions were taken to ensure its removal. This entailed exposure of the product mixture to conditions that promote deliberate spirocyclization of the seco phenol derivatives [saturated aqueous NaHCO 3 -THF (1:1), 23° C., 2 hours (h)] and subsequent chromatographic separation of the much more polar CBI-TMI or CBI-indole 2 . N-Acetylation of 4 (Ac 2 O, cat. DMAP, CH 2 Cl 2 , 23° C., 12 h, 81%) provided 6 and subsequent Boc deprotection (TFA-CH 2 Cl 2 (1:1), 23° C., 3 hours, 88%) afforded 5. In an analogous manner, seco-CBI-indole 2 (3) was directly converted to 8 (45%) upon LiHMDS deprotonation (3 equiv of LiHMDS, ether-dioxane, 0° C., 30 minutes) and subsequent O-amidation with TsONHBoc (Greck, C.; et al. Bull. Soc. Chim. Fr. 1994, 131, 429).
For comparison purposes, two analogues of seco-CBI-TMI were prepared that are incapable of spirocyclization to CBI-TMI itself. The first incorporates the C4 phenol protected as its methyl ether (10) and second contains no C4 substituent (9). The former was prepared from 11 (Kastrinsky, D. B.; Boger, D. L. J. Org. Chem. 2004, 69, 2284) by phenol O-methylation, primary alcohol OTBS deprotection and subsequent conversion to the primary chloride 14, followed by N-Boc deprotection and coupling with 5,6,7-trimethoxyindole-2-carboxylic acid (15) to provide 10. See, Scheme 2, below.
Throughout this sequence and as a result of the multiple purifications, the chances of residual, contaminant phenol (2) being present in the final product 10 are remote. Nonetheless, because even trace quantities of 2 can be misleadingly detected in the subsequent biological evaluations (e.g., 0.01%), the inactive analogue 9 was also prepared for comparison and by an approach that precludes the presence of such a contaminate phenol because there is no C-4 functionality in the starting material 16.
Thus, following a route analogous to that used for CBI itself (Boger, D. L.; et al. J. Org. Chem. 1992, 57, 2873; Boger, D. L.; McKie, J. A. J. Org. Chem. 1995, 60, 1271; Drost, K. J.; Cava, M. P. J. Org. Chem. 1991, 56, 2240; Aristoff, P. A.; Johnson, P. D. J. Org. Chem. 1992, 57, 6234; Mohamadi, F.; et al. J. Med. Chem. 1994, 37, 232; Ling, L.; et al. Heterocyclic Commun. 1997, 3, 405; Boger, D. L.; et al. Synlett 1997, 515; Boger, D. L.; et al. Tetrahedron Lett. 1998, 39, 2227; Kastrinsky, D. B.; Boger, D. L. J. Org. Chem. 2004, 69, 2284), 20 was prepared from 16 and converted to 21 enlisting a key 5-exo-trig aryl radical-alkene cyclization (Boger, D. L.; et al. Tetrahedron Lett. 1998, 39, 2227). See, Scheme 3, below, that also illustrates the synthesis of the analog of CBI-TMI, 9.
Compound 20 was converted to 21 enlisting a key 5-exo-trig aryl radical-alkene cyclization (Boger, D. L.; et al. Tetrahedron Lett. 1998, 39, 2227). The product 21, like 14 (α=1.19), was chromatographically resolved on a semipreparative ChiralCel OD column (α=1.42) providing each enantiomer, and 21 was coupled with 5,6,7-trimethoxyindole-2-carboxylic acid (15) upon N-Boc deprotection to provide 9.
Stability and Reactivity of the N-Acyl O-Amino Phenol Derivatives
Clear from efforts directed at their preparation, the N-acyl amino phenol prodrugs displayed a useful range of stability, yet were susceptible to cleavage of the critical N—O bond. As might be anticipated, their relative stability followed the order of 4>5>6>7 with 4 and 5 withstanding even long term storage effectively, but with 7 noticeably deteriorating over time. Derivatives 4 and 6, as well as 7, proved surprisingly robust to acidic conditions (TFA-CH 2 Cl 2 , 4 NHCl-EtOAc), and stable to mild base treatment in nonpolar, aprotic solvents (Et 3 N or DMAP, CH 2 Cl 2 ), but exhibited a diminished stability as the solvent polarity increases: stable to NaHCO 3 in THF or THF-H 2 O, but cleaved in NaHCO 3 /DMF-H 2 O or H 2 O and DBU/CH 3 CN. Similarly, 4 proved stable in MeOH, but 2 was released slowly upon treatment with NaHCO 3 or Na 2 CO 3 in MeOH (2 hours, 23° C.). Most pertinent to the potential source of cleavage under physiological conditions, 4 was stable to treatment with BnSH in THF (2-72 hours, 23° C.) or MeOH (2-72 hours, 23° C.), and stable to treatment with BnSH in THF even in the presence of insoluble NaHCO 3 (2 hours, 23° C.), but is cleaved to release 2 upon treatment with BnSH in MeOH in the presence of NaHCO 3 (2 hours, 23° C.). Significantly, the stability of 4 was assessed in pH 7.0 phosphate buffer and within the limits of detection (HPLC, UV), no significant cleavage of the prodrug was observed over the time monitored (72 hours). The stability of 4 was monitored in human plasma (50 μg/100 μL, 10% DMSO) in which it displayed a half-life of 3 hours with release of the free drug 2.
Biological Properties
Cytotoxic Activity
The O-amino phenol derivatives bearing the N—O prodrug linkages and the various N-acyl substituents were assayed for cytotoxic activity alongside the parent drugs CBI-TMI (2) (Boger, D. L.; Yun, W. J. Am. Chem. Soc. 1994, 116, 7996) and mitomycin C (Boger, D. L.; et al. Bioorg. Med. Chem. Lett. 1991, 1, 115; Boger, D. L.; et al. Bioorg. Med. Chem. 1995, 3, 1429) as well as the two control standards 9 and 10 incapable of free phenol release. Three cell lines were examined including a standard L1210 cell line (mouse leukemia) as well as the mitomycin-sensitive (H460, expresses high levels of DT-Diaphorase) and resistant (H596, lacks DT-Diaphorase) non small cell lung cancer (NSCLC) cell lines, with results shown in the Table below.
Natural enantiomer series
IC 50 (nM)
Compd, R
L1210
H460
H596
mitomycin C
40
20
5000
9, H
>100
>100
>100
10, OMe
50
>100
>100
2, OH
0.04
0.5
5
4, ONHBoc
0.5
1
6
5, ONHAc
0.3
0.7
7
6, ON(Ac)Boc
0.2
0.6
5
7, ONPhth
0.06
0.5
5
Several important trends emerged from these studies. First, the natural enantiomer control standards 9 and 10, incapable of free phenol release, were inactive against all three cell lines (IC 50 >100 nM) being ≧10,000-fold less active than the free drug 2 (seco-CBI-TMI). In sharp contrast, the natural enantiomers of the O-amino phenol prodrugs exhibited potent cytotoxic activity approaching that of the free drug itself (1-0.1 times the activity of 2) indicating its successful release under the assay conditions.
Even more significantly, the relative potency of the prodrugs, when distinguishable, mirrors the expected ease of N—O bond cleavage (e.g. L1210: 7>6>5>4) suggesting fundamental chemical principles can be used to “tune” the reductive free drug release. Provocatively, the potency differences between the free drug 2 and the prodrugs diminish as the hypoxic character of the cell line increases; 4 is 10-fold less potent than 2 against L1210, but 2 and 4 are essentially equipotent against H460/H596.
More significantly and unlike mitomycin C, this reductive activation is not linked to the expression levels of DT-Diaphorase because 2 and 4-7 remain equipotent in the H460 or H596 cell lines, although H596 is 10-fold less sensitive than H460 to seco-CBI-TMI itself. This result illustrates that DT-Diaphorase is not mediating the reductive release of the drug from the O-amino phenol prodrugs, indicating that their utility is orthogonal to that of mitomycin. Rather, their behavior is consistent with the suggestion that the activation is nonenzymatic and likely is mediated in situ by appropriate nucleophiles.
Analogous trends are also observed with the CBI-TMI unnatural enantiomers albeit at concentrations that are approximately 100 to 1000-fold higher than that of the natural enantiomers as is seen in the Table below.
Unnatural enantiomer series
IC 50 (nM)
Compd, R
L1210
H460
H596
mitomycin C
40
20
5000
9, H
900
5500
>10000
10, OMe
800
5000
>10000
2, OH
5
50
300
4, ONHBoc
160
900
6400
5, ONHAc
100
700
6300
6, ON(Ac)Boc
70
600
6300
7, ONPhth
60
600
6000
Especially interesting and exciting was the behavior of the CBI-indole 2 prodrug. For this CBI analogue, only the NHBoc derivative was examined because it was the most stable of the N-acyl O-amino phenol prodrugs examined as is seen from the data below.
Natural enantiomer series
IC 50 (nM)
Compd, R
L1210
H460
H596
mitomycin C
40
20
5000
3, OH
0.03
0.2
2
8, ONHBoc
0.05
0.3
4
Unnatural enantiomer series
IC 50 (nM)
Compd, R
L1210
H460
H596
mitomycin C
40
20
5000
3, OH
0.7
6
40
8, ONHBoc
2
10
60
In each cell line examined, the prodrug 8 was essentially equipotent with CBI-indole 2 (3) itself, indicating effective release of the free drug under the conditions of the assay. In addition prodrug 8 proved to be exceptionally potent, being 100-1000 times more active than mitomycin C (IC 50 =30-200 pM vs 20-40 nM) and it remained remarkably active against the mitomycin-resistant H596 cell line (IC 50 =4 nM vs 5 μM). Even the unnatural enantiomer of prodrug 8, which was found to be 10-100 fold less active than the natural enantiomer, proved to be more active than mitomycin C. Given the efficacy of (+)-CBI-indole 2 in animal tumor models, (Boger, D. L.; Ishizaki, T.; Sakya, S. M.; Munk, S. A.; Kitos, P. A.; Jin, Q.; Besterman, J. M. Bioorg. Med. Chem. Lett. 1991, 1, 115; Boger, D. L.; Yun, W.; Han, N. Bioorg. Med. Chem. 1995, 3, 1429) it was especially interesting to compare 8 with 3 in vivo.
DNA Alkylation Selectivity and Efficiency
The DNA alkylation properties of 4 were examined alongside the parent drug CBI-TMI (2), and the two control standards 9 and 10 (incapable of spirocyclization) within w794 duplex DNA (Boger, D. L.; et al. Tetrahedron 1991, 47, 2661) for which results for an extensive series of duocarmycin analogues have been reported. The sites of DNA alkylation and its efficiency were directly assessed by thermally-induced singly 5′ end-labeled duplex DNA strand cleavage following incubation with the agents (FIG. 8, natural enantiomers examined).
The reductively activated agent 4 was found to alkylate w794 DNA with an identical sequence selectivity as the parent agent CBI-TMI (2), albeit with a substantially reduced efficiency (1,000-10,000 fold). Similarly, the O-methyl ether 10 as well as 9 lacking a C4 substituent failed to exhibit significant observable DNA alkylation. In fact, 9 showed no appreciable DNA alkylation even under forcing conditions (37° C., 18 hours, data not shown), whereas the potentially more reactive O-methyl ether 10 (via assisted phenonium ion formation) displayed perhaps a trace amount of DNA alkylation (<0.01% that of 2) that could be attributed to either its direct, but much less facile, DNA alkylation or contaminant free phenol present in the synthetic sample of 10.
With detection of DNA alkylation by the prodrug 4 at the level observed (0.1-0.01% of 2), one cannot distinguish whether this is due to direct alkylation by 4 itself, trace release of 2 from 4 under the DNA incubation conditions (in situ N—O cleavage), or attributable to trace contaminate 2 in the synthetic samples of 4. What the results do indicate is that 4 is incapable of significant DNA alkylation in its own right (requires N—O bond cleavage), and that 4 is essentially stable to the DNA alkylation conditions examined requiring deliberate N—O bond cleavage to initiate effective DNA alkylation. These observations are consistent with the stability of 4 observed in pH 7.0 phosphate buffer. Significantly, the results then suggest that the in vitro cytotoxic activity of 4, and by analogy that of the related O-amino phenol prodrugs that all approach that of the parent drug CBI-TMI (2), is derived from in situ intracellular cleavage of the N—O bond and productive release of the active drug under the cell culture conditions.
In Vivo Antitumor Activity
The prodrug 8 was examined for in vivo efficacy alongside the parent drug 3 in a standard antitumor model enlisting L1210 murine leukemia implanted i.p. into DBA/2J mice. This model has been reported to respond well to the parent drugs of related compounds (Li, L. H.; et al. Invest. New Drugs 1991, 9, 137) and is a system that collaborators through the years have used to assess an extensive series of (+)-CBI-indole 2 analogues. Although not published, these latter studies provided the foundation on which examination of 8 is based.
With use the dose range (10-100 μg/kg) and the dosing schedule (administered three times i.p. on days 1, 5, and 9) found suitable for related parent drugs including (+)-CBI-indole 2 (3) (Boger, D. L.; et al. Bioorg. Med. Chem. Lett. 1991, 1, 115; Boger, D. L.; et al. Bioorg. Med. Chem. 1995, 3, 1429), the prodrug 8 was examined as is shown in the Table below.
Mean Survival
Dose
Period (MSP)
Treated/Control
Surviving
Compound
μg/kg
(days)
(MSP × 100)
Mice
none
0
20
100
0/6
8
10
25
120
0/6
8
30
>145
>730
2/6
8
100
>310
>1550
5/6
3
10
34
170
0/6
3
30
>115
>580
1/6
3
100
125
625
0/6
The dose at which a maximal response was observed for 8 corresponded closely to that of (+)-CBI-indole 2 (3) whereas its efficacy was significantly improved. This result indicates that the prodrug 8 (a) efficiently and effectively releases the free drug 3 in the in vivo model (reductive activation), and (b) that either the rate of release or the site of release enhances the efficacy of the drug. Moreover, the efficacy of 8 is extraordinary providing 5/6 long-term survivors at 52 weeks (365 days, T/C>1550) at the optimal dosing examined (100 μg/kg). Notably, little distinction between 3 and 8 was observed at days 30-100 except that the prodrug-treated animals appeared healthier, displaying little or no weight loss that was evident with 3 at the highest dosing.
With the prolonged management of the treated animals herein that exceeded the time frame typically allotted for such an in vivo antitumor assessment, it was observed that the surviving mice at day 90 treated with the free drug 3, but not the prodrug 8, eventually expired due to drug administration related complications. (This appears to arise from damage to the intraperitoneal cavity or its organs that originate with the bolus drug administration.) Although these administration effects would likely be capable of being managed with an optimized dosing schedule, this distinction between 3 and 8 in the long-term cures (>90 days) suggests the prodrug 8 offers significant advantages over the free drug administration.
It is also worth noting that these compounds are extraordinarily potent, requiring less than 1 mg of sample to conduct the entire in vivo antitumor testing, suggesting that clinical supplies of such agents could easily be supplied by chemical synthesis.
Confirming these observations, an analogous antitumor assessment was carried out independently at a second site utilizing a slightly different and harsher protocol for drug administration (neat DMSO vs 30% DMSO in 0.1% glucose). Although this assessment was terminated after 120 days, it similarly indicates that administration of the prodrug 8 is significantly less toxic than free drug 3, and that it is comparable or superior in terms of reducing deaths due to the disease, tumor counts, and tumor volume as seen from the Table below. Again, 7/10 long-term survivors were observed with prodrug 8 at day 120 at the optimal dosing (60 μg/kg).
Mean Survival
Dose
Period (MSP)
Treated/Control
Surviving
Compound
μg/kg
(days)
(MSP × 100)
Mice
none
0
22
100
0/10
8
10
>46
>210
2/10
8
30
>51
>232
2/10
8
60
>93
>425
7/10
8
100
>63
>288
3/10
3
10
>60
>271
3/10
3
30
>65
>295
3/10
3
60
>71
>324
3/10
3
100
11
52
0/10
In the above Table, the second column is the dose in mg/kg of body weight of the animal that is administered i.p. (into the intraperitoneal cavity) on days 1, 5, and 9. The surviving mice are the number of mice that are still living after 120 days and the experiment was then terminated.
Experimental
DNA Alkylation Selectivity and Efficiency
The DNA alkylation reactions were performed by treatment of 4.5 μL of singly 32 P 5′-end-labeled double-stranded w794 DNA (Boger, D. L.; et al. Tetrahedron 1991, 47, 2661) in TE buffer (10 mM Tris, 1 mM EDTA, pH 7.6) with 0.5 μL of agent in EtOH (at the specified concentration). The samples were incubated for 18 h at 4° C. Unbound agent was removed by EtOH precipitation of DNA (0.5 μL of 3.0 M sodium acetate and 12.5 μL of cold absolute EtOH) and the solutions were stored at −78° C. for 1 hour or longer. The DNA was pelleted by centrifugation at 4° C. (13000 rpm, 25 minutes), dried in a Savant Speed Vac concentrator, and resuspended in 5 μL of TE buffer (pH 7.6). Thermal depurination (3×10 minutes at 100° C.) was performed and then 2.5 μL of formamide dye solution was added to the cooled samples. Thermally denatured samples were assayed by gel electrophoresis [8% denaturing gel with 8 M urea in TBE buffer (89 mM Tris-borate, 2 mM EDTA)] followed by autoradiography of the dried gel using Kodak BIOMAX XAR film and a Picker Spectra™ intensifying screen.
A solution of 2-naphthoic acid (16, 1.5 g, 8.7 mmol) in t-BuOH (50 mL) and toluene (50 mL) was treated with Et 3 N (1.44 mL, 10 mmol), 3 Å molecular sieves (10 g) and diphenyl phosphorylazide (2.1 mL, 10 mmol). The reaction mixture was warmed at reflux for 24 h and then cooled to 23° C. The solid was filtered off through Celite and the solvent was removed in vacuo. The residue was dissolved in EtOAc (75 mL), and the organic phase was washed with 1 N aqueous HCl (50 mL×2), saturated aqueous NaHCO 3 (50 mL×2), dried over anhydrous sodium sulfate, and concentrated. Chromatography (SiO 2 , 10% EtOAc/hexane) afforded 17 as a pale yellow solid (1.56 g, 74%): ESI-TOF HRMS m/z 266.1150 (M+Na + , C 15 H 17 NO 2 requires 266.1151).
Compound 17 (1.5 g, 6.2 mmol) was treated with 4 NHCl-EtOAc (50 mL) for 1 hour before the solvent was removed to yield a white powder. The crude HCl salt (790 mg, 5.5 mmol), and TsOH (170 mg, 1.1 mmol) in THF (50 mL) cooled to 0° C. was treated with NBS (982 mg, 5.5 mmol) in THF (30 mL), and the solution was allowed to warm to 23° C. After stirring for 5 hours, the reaction mixture was washed with saturated aqueous NaHCO 3 (30 mL×2). The organic layer was dried over anhydrous sodium sulfate and was concentrated. Chromatography (SiO 2 , 10% EtOAc/hexane) afforded 18 (863 mg, 59% for two steps): ESI-TOF HRMS m/z 221.9910 (M+H + , C 10 H 8 BrN requires 221.9913).
A solution of 18 (800 mg, 3.6 mmol) in CH 2 Cl 2 was treated with Et 3 N (496 μL, 3.6 mmol), DMAP (36 mg, 0.36 mmol), and Boc 2 O (830 mg, 3.8 mmol) and the reaction mixture was stirred at 55° C. for 36 hours. The reaction mixture was cooled to 23° C. and washed with aqueous 1 N HCl (30 mL×2), and saturated aqueous NaHCO 3 (30 mL×2). The organic layer was dried over anhydrous sodium sulfate, and concentrated. Chromatography (SiO 2 , 10% EtOAc/hexanes) provided the product as a white solid (1.25 g, 83%): ESI-TOF HRMS m/z 444.0780 (M+Na + , C 20 H 24 BrNO 4 requires 444.0781).
A solution of the product above (516 mg, 1.18 mmol) in MeOH (20 mL) was treated with K 2 CO 3 (490 mg, 3.6 mmol), and the resulting mixture was warmed at reflux for 1.5 hours. The reaction mixture was allowed to cool to 23° C. and filtered through Celite to remove solid residue. The solvent was removed to yield 19 as a white solid (448 mg, quant.), which was sufficiently pure to use for next step without further purification: ESI-TOF HRMS m/z 344.0250 (M+Na + , C 15 H 16 BrNO 2 requires 344.0257).
A solution of 19 (980 mg, 3 mmol) in DMF (20 mL) was treated with NaH (60%, 304 mg, 7.5 mmol) and Bu 4 NI (11 mg, 0.3 mmol) at 0° C. After stirring for 15 minutes, 1,3-dichloropropene (0.8 mL, 9 mmol) was added, and the resulting mixture was warmed to 23° C. and stirred for another 4 hours. The reaction mixture was diluted with EtOAc (50 mL) and washed with saturated aqueous NH 4 Cl (30 mL×2). The organic layer was dried over anhydrous sodium sulfate and concentrated. The crude product 20 was used for the next step without further purification.
A solution of crude 20 (1.0 g, 2.52 mmol) and AIBN (41 mg, 0.25 mmol) in degassed toluene (40 mL) was treated with Bu 3 SnH (0.75 mL, 2.77 mmol). The resulting solution was purged with N 2 gas for 10 minutes and then warmed at reflux overnight (about 18 hours). The solvent was removed and the crude product was purified by chromatography (SiO 2 , 10% EtOAc/hexanes) to yield racemic 21 as a white solid (780 mg, 97%). The two enantiomers were separated by chromatography (semiprep 2×25 cm Chiral OD column, 10% iPrOH/hexanes, flow rate=0.5 mL/min, t R =35.5 min (natural), 25.0 min (unnatural), α=1.42): ESI-TOF HRMS m/z 340.1076 (M+H + , C 28 H 20 ClNO 2 requires 340.1075). 1S-21: [α] 23 D −0.38 (c 0.18, CH 3 OH), natural enantiomer; 1R-21: [α] 23 D +0.46 (c 0.13, CH 3 OH), unnatural enantiomer.
A sample of 21 (13 mg, 41 μmol) was treated with 4 NHCl-EtOAc (3 mL) for 30 min before the solvent was removed by a stream of N 2 . The resulting crude HCl salt, 5,6,7-trimethoxyindol-2-carboxylic acid (15, 10.3 mg, 41 μmol) and EDCI (24 mg, 0.12 mmol) were dissolved in DMF (3 mL), and the resulting solution was stirred at 23° C. for 3 hours. The reaction mixture was diluted with EtOAc (15 mL) and washed with aqueous 1 N HCl (5 mL×2), and saturated aqueous NaHCO 3 (5 mL×2). The organic layer was dried over anhydrous sodium sulfate, and concentrated. PTLC (SiO 2 , 50% EtOAc/hexanes) gave 9 as a white solid (13.6 mg, 74%): ESI-TOF HRMS m/z 451.1420 (M+H + , C 25 H 23 ClN 2 O 4 requires 451.1419). 1S-9: [α] 23 D −0.26 (c 0.46, THF), natural enantiomer; 1R-9: [α] 23 D +0.27 (c 0.73, THF), unnatural enantiomer.
A solution of 11 (Kastrinsky, D. B.; Boger, D. L. J. Org. Chem. 2004, 69, 2284) (50 mg, 0.116 mmol), and methyl iodide (14.5 μL, 0.233 mmol) in acetone (12 mL) was treated with K 2 CO 3 (48 mg, 0.349 mmol) at 23° C., and the resulting mixture was stirred at 23° C. for 3 hours. The reaction was diluted with water (10 mL) and extracted with EtOAc (15 mL×2). The combined organic layers were washed with water (15 mL×2), saturated aqueous NaCl (15 mL) and dried over anhydrous sodium sulfate. The solvent was removed and the crude product 12 was sufficiently pure for use without further purification (55 mg, quant.).
A solution of 12 (51 mg, 0.115 mmol) in THF (5 mL) was treated with Bu 4 NF (1 M in THF, 575 μL, 0.575 mmol) at 23° C. After stirring at 23° C. for 1 hour, the reaction mixture was diluted with EtOAc (20 mL) and washed with water (10 mL), and saturated aqueous NaCl (10 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated to afford pure 13 (40 mg, quant.). The above crude compound 13 (40 mg, 0.121 mmol) was dissolved in pyridine (2 mL). Methanesulfonyl chloride (59 μL, 0.607 mmol) was added at 0° C. After stirring at 23° C. for 6 hours, the reaction mixture was diluted with EtOAc (20 mL), and washed with water (10 mL×2), and saturated aqueous NaCl (10 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. The crude residue was dissolved in DMF (2 mL) and was treated with LiCl (26 mg, 0.607 mmol). After stirring at 23° C. for 3 days, the reaction mixture was diluted with EtOAc (20 mL) and washed with water (10 mL), saturated aqueous NaCl (10 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. Chromatography (SiO 2 , 20% EtOAc/hexanes) afforded 14 (37.5 mg, 93% for two steps). The two enantiomers were separated by chromatography (semiprep 2×25 cm Chiral OD column, 10% iPrOH/hexanes, flow rate=0.5 mL/min, t R =14.4 min (natural), 12.1 min (unnatural), α=1.19): 1S-14: [α] 23 D −0.43 (c 0.28, THF), natural enantiomer; 1R-14: [α] 23 D +0.45 (c 0.53, THF), unnatural enantiomer.
A sample of 14 (6.1 mg, 17 μmol) was treated with 4 NHCl-EtOAc (0.6 mL) for 30 minutes before the solvent was removed by a stream of N 2 . The resulting crude HCl salt, 5,6,7-trimethoxyindol-2-carboxylic acid (15, 4.8 mg, 19 μmol) and EDCI (10.1 mg, 0.05 mmol) were dissolved in DMF (0.15 mL) and the resulting solution was stirred at 23° C. for 3 hours. EtOAc (10 mL) was added to the reaction mixture and the resulting solution was washed with aqueous 1 N HCl (5 mL×2), saturated aqueous NaHCO 3 (5 mL×2), dried over anhydrous sodium sulfate and concentrated. PTLC (SiO 2 , 50% EtOAc/hexanes) gave 10 as a white solid (5.5 mg, 65%): ESI-TOF HRMS m/z 481.1521 (M+H + , C 26 H 25 ClN 2 O 5 requires 481.1525). 1S-10: [α] 23 D −0.50 (c 0.31, THF), natural enantiomer; 1R-10: [α] 23 D +0.86 (c 0.14, THF), unnatural enantiomer.
A solution of seco-CBI-TMI (Boger, D. L.; Yun, W. J. Am. Chem. Soc. 1994, 116, 7996) (2, 30 mg, 0.064 mmol) in ether-dioxane (1:1, 3 mL) was treated with LiHMDS (1 M in THF, 193 μL, 0.193 mmol) at 0° C., and the resulting mixture was stirred at 0° C. for 30 minutes. The resulting solution was treated with t-butyl-N-tosyloxycarbamate (55 mg, 0.193 mmol). The reaction mixture was allowed to warm to 23° C. and stirred for an additional 4 hours. The solution was diluted with EtOAc (20 mL) and washed with water (10 mL), and saturated aqueous NaCl (10 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. PTLC (SiO 2 , 50% EtOAc/hexanes) afforded crude product (31.2 mg). To ensure the complete removal of any 2, the product (12 mg) was dissolved in THF (6 mL) and saturated aqueous NaHCO 3 (6 mL) was added. After stirring at 23° C. for 2 hours to promote spirocyclization of any residual 2 to the much more polar and easily separable CBI-TMI, the reaction mixture was diluted with EtOAc (20 mL), washed with water (10 mL) and saturated aqueous NaCl (10 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. PTLC (SiO 2 , 20% EtOAc/hexanes) afforded 4 (6.6 mg, 46%) as a pale yellow solid: ESI-TOF HRMS m/z 582.2000 (M+H + , C 30 H 32 ClN 3 O 7 requires 582.2001). 1S-4: [α] 23 D −0.39 (c 0.31, THF), natural enantiomer; 1R-4: [α] 23 D +0.68 (c 0.44, THF), unnatural enantiomer.
A solution of 4 (3.4 mg, 0.00584 mmol) in CH 2 Cl 2 (0.34 mL) was treated with acetic anhydride (2.7 μL, 0.0292 mmol), Et 3 N (4.1 μL, 0.0292 mmol) and DMAP (cat). After the resulting mixture was stirred at 23° C. for 12 hours, the solvent was removed and the residue was purified by PTLC (SiO 2 , 50% EtOAc/hexanes) to afford 6 (2.9 mg, 81%): ESI-TOF HRMS m/z 642.2102 (M+H + , C 32 H 34 ClN 3 O 8 requires 642.2107). 1S-6: [α] 23 D −0.43 (c 0.23, THF), natural enantiomer; 1R-6: [α] 23 D +0.54 (c 0.52, THF), unnatural enantiomer.
A solution of 6 (3.1 mg, 0.0053 mmol) in CH 2 Cl 2 (1 mL) was treated with TFA (1 mL) at 23° C. for 3 hours. The solvent and excess TFA were removed and the residue was purified by PTLC (SiO 2 , 50% EtOAc/hexanes) to afford 5 (2.3 mg, 88%): ESI-TOF HRMS m/z 522.1431 (M−H, C 22 H 26 ClN 3 O 6 requires 522.1437). 1S-5: [α] 23 D −1.2 (c 0.10, THF), natural enantiomer; 1R-5: [α] 23 D +0.76 (c 0.21, THF), unnatural enantiomer.
A solution of seco-CBI-TMI (2, 5.0 mg, 0.011 mmol) in THF (0.5 mL) was treated with LiHMDS (1 M in THF, 13 μL, 0.013 mmol) at −78° C., and the resulting mixture was stirred at −78° C. for 30 minutes. The resulting solution was treated with N-p-tolylsulfonyloxyphthalimide (5.1 mg, 0.016 mmol). The reaction mixture was stirred at 23° C. for an additional 60 minutes. The solution was diluted with EtOAc (10 mL) and washed with water (5 mL), and saturated aqueous NaCl (5 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. PTLC (SiO 2 , 50% EtOAc/hexanes) afforded 7 (4.6 mg, 70%) as a pale yellow solid: 1S-7: [α] 23 D −0.42 (c 0.28, THF), natural enantiomer; 1R-7: [α] 23 D +0.53 (c 0.36, THF), unnatural enantiomer.
A solution of seco-CBI-indole 2 (Boger, D. L.; Yun, W.; Han, N. Bioorg. Med. Chem. 1995, 3, 1429) (3, 16.5 mg, 0.031 mmol) in THF (1.5 mL) was treated with LiHMDS (1 M in THF, 93 μL, 0.093 mmol) at 0° C. and the mixture was stirred at 0° C. for 30 minutes. The resulting solution was treated with t-butyl-N-tosyloxycarbamate (26.6 mg, 0.093 mmol), and the reaction mixture was allowed to warm to 23° C. and stirred for an additional 4 hours. The solution was diluted with EtOAc (20 mL) and washed with water (10 mL), and saturated aqueous NaCl (10 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. PTLC (SiO 2 , 50% THF/hexanes) afforded 8 (12.0 mg). The product (12 mg) was dissolved in THF (6 mL) and treated with saturated aqueous NaHCO 3 (6 mL) to promote the spirocyclization of any residual 3. After stirring at 23° C. for 2 hours, the reaction mixture was diluted with EtOAc (20 mL), washed with water (10 mL) and saturated aqueous NaCl (10 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. PTLC (SiO 2 , 20% THF/hexanes) afforded 8 (9.0 mg, 45%): ESI-TOF HRMS m/z 650.2150 (M+H + , C 36 H 32 ClN 5 O 5 requires 650.2165). 1S-8: [α] 23 D +2.1 (c 0.50, THF), natural enantiomer; 1R-8: [α] 23 D −2.0 (c 0.89, THF), unnatural enantiomer.
In Vivo Antitumor Activity
DBA/2J mice were purchased from Jackson Laboratory (Bar Harbor, Me.) and housed in the animal facility at The Scripps Research Institute. L1210 tumor cells, originally isolated from DBA/2 mice, were cultured in DMEM medium containing 5% fetal calf serum. For tumor implantation, DBA/2J mice were i.p. injected with 1×10 5 L1210 cells at day 0.
Compounds 3 and 8 were formulated with 30% DMSO plus 0.1% glucose solution. Treatment doses of drugs (0, 10, 30, 100 lg/kg wt. of animal) were i.p. injected consecutively on day 1, 5 and 9. The study was performed with six mice per group. Tumor growth in the peritoneal cavity was monitored daily and the death of animals was recorded. If necessary, weights of animals were measured once a week. To date this monitoring of the animals has lasted 365 days.
An analogous study with 10 mice per group was performed at the University of Kansas with the distinction that the compounds were administered in neat DMSO (0, 10, 30, 60, 100 lg/kg wt. of animal) and the study was terminated after 120 days.
Each of the patents, patent applications and articles cited herein is incorporated by reference. The use of the article “a” or “an” is intended to include one or more.
The foregoing description and the examples are intended as illustrative and are not to be taken as limiting. Still other variations within the spirit and scope of this invention are possible and will readily present themselves to those skilled in the art. | A unique class of N-acyl O-amino phenol prodrugs of CBI-TMI and CBI-indole 2 were synthesized and shown to be prodrugs, subject to reductive activation by nucleophilic cleavage of a weak N—O bond, effectively releasing the free drug in functional cellular assays for cytotoxic activity approaching or matching the activity of the free drug, yet remain essentially stable to ex vivo DNA alkylation conditions. Most impressively, assessment of the in vivo antitumor activity of a representative O-(acylamino) prodrug, 8, indicate that they approach the potency and exceed the efficacy of the free drug itself (CBI-indole 2 ), indicating that the inactive prodrugs not only effectively release the free drug in vivo, but that they offer additional advantages related to a controlled or targeted release in vivo. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a valve arrangement for use with a valve system regulating delivery of a pressure medium, and more particularly, an arrangement which permits facilitated adjustment of a force required to actuate such a valve system.
A known such valve arrangement is disclosed, for example, in the WABCO Westinghouse publication "Motorwagen-Bremsventil (Motor Car Brake Valve) 461 106 Page 1," August 1973 edition, and in which a pedal serves as an operating element for brake actuation. A similar system is also disclosed in EP 0 241 437 A1 (corresponding U.S. Pat. No. 4,741,579 entitled "PNEUMATIC DISTRIBUTOR OF THE DUPLEX TYPE FOR MOTOR VEHICLE BRAKING SYSTEMS," issued to Angelillo Domenico on May 3, 1988). In the known arrangements disclosed therein, a supplied pressure exerts a pressure force over an active surface of a graduating piston, and a return spring used to restore the graduating piston exerts a spring force on the actuating element when the valve system is actuated by downward urging of the operating element. During intermittent periods in which the inlet valve of the valve system is opened by operator-actuation, a spring used to ensure secure closure of the inlet valve and a return spring serving to restore a valve body together exert another spring force on the operating element. The actuating force exerted by the operator on the operating element must overcome these forces, or, must resist them in order to maintain continued valve actuation. The combined spring-related biasing forces are low compared to the pressure force. The spring force of the spring which restores the graduating piston is furthermore nearly constant because of its low spring deflection. The actuating force therefore essentially depends on the lever ratios between operating element and valve system, in addition to the value of the pressure delivered at a given time. The evolution of the actuating force as a function of the delivered pressure shall be hereinafter be referred to as the "actuation force requirement."
Often, an application requires a change in these lever ratios, for example due to a change of the length of the operating element, while nevertheless requiring that a value of the actuation force requirement be maintained. Conversely, there are applications requiring a change in the actuation force requirement while the lever ratios remain unchanged. Such applications occur in particular when the installed actuating element is separated from the valve system, as is provided, for example, in the WABCO Westinghouse publication "Motorwagen-Bremsventil (Motor Car Brake Valve) 461 295," August 1973 edition. A comparable system is also disclosed in FIG. 4 on page 6 of the Clayton Dewandre Air Pressure Equipment Brochure "E, E-1, E-2, & DUAL E BRAKE VALVES." In such cases, is not possible to properly adapt the system without changing the diameter of the graduating piston, and therefore not without requiring associated additional changes in the valve system. These changes, which require a redesign of the valve system, result in high development costs. Furthermore, the increased number of versions caused therby contribute to increased manufacturing, material and storage costs, among others drawbacks.
It is therefore the object of the present invention to develop an arrangment of the type mentioned above which permits the actuation force requirement thereof to be adapted to various applications with little or no changes in the valve system.
SUMMARY OF THE INVENTION
In accordance with these and other objects of the invention, there is provided an arrangement for use with a valve system which permits facilitated adaptation thereof to conditions where modified lever ratios are desired while an actuation force requirement is to remain unaffected, or where a modified actuating force requirement is desired while lever ratios remain unchanged. In order to avoid or reduce costs associated with modification of the actuation force requirement of the valve system, a spring is provided which acts upon the operating element, in addition to a pressure force against the actuating force in such manner that a predetermined actuating force requirement results.
Briefly stated, a valve arrangement is provided for the delivery of pressure from a pressure supply, the arrangement including a valve system and an operating element for actuating the valve arrangement by the imparting of actuating force thereto. In such arrangement, the delivered pressure in the valve system exerts a pressure force against the operating element which resists the actuating force thereon. At least one spring which exerts a spring force upon the operating element, in addition to the pressure force thereby assisting the pressure force. The spring force is selected such that a predetermined actuation force requirement is achieved.
Valve arrangements of the type mentioned above are employed in all technical areas in which pressure-operated control systems, in particular pneumatic control systems, are used. Pneumatic vehicle braking systems represent a significant area of application for embodiment of the invention.
The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a schematic view of a valve arrangement in accordance with an embodiment of the invention; and
FIG. 2 is a schematic view of a valve arrangement in accordance with another embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the figures, and in particular FIG. 1, a valve arrangement in accordance with an embodiment of the invention is shown, the valve arrangement including a valve system 14, an operating element 12, a transmission link 9 and a spring 7.
Operating element 12 can be pivotably moved about a bearing shaft 11 to which it is rotatably mounted. Although shown conveniently in the form of a pedal, it is noted that operating element 12 can be provided in various other suitable forms providing analogous function without departure from the invention. It is also acceptable to provide a bearing axle alternative to use of bearing shaft 11. A bearing element 10 serves as a support for valve system 14 and operating element 12, which, in automotive applications, is generally comprised of a part of the floor of a driver's cab or a front structure thereof. In a non-actuated state, operating element 12 is biased in a rest position against a stop carried on bearing element 10 by spring 7 captively disposed between operating element 12 and bearing element 10. In the embodiment as depicted in FIG. 1, spring 7 is conveniently held on operating element 12 via a spring plate 8 which is urged by spring 7 against a shoulder of the transmission link 9. It is noted, however, that spring 7 can alternatively be held in any other suitable manner accomplishing a like result.
Valve system 14 can be produced in a simple manner, for example, from the valve system described in the aforementioned WABCO Westinghouse publication "Motorwagen-Bremsventil (Motor Car Braking Valve) 461 295."
Valve system 14 as shown includes a graduating piston 3 movable substantially in the longitudinal direction of transmission link 9 and biased in a direction of operating element 12 by a return spring 2, and a valve body 17 biased in a common direction by a return spring 18. Valve system 14 is connected via a supply port 16 to a pressure supply 15, and to one or more consumers 1, such as for example brake cylinders, via a delivery port 19.
The operator actuates the valve arrangment by pivotably rotating operating element 12 against the force of the spring 7. A stroke corresponding in degree to the applied rotation, in the form of substantially longitudinal displacement of transmission link 9, is transmitted to valve system 14. In response thereto, valve system 14 delivers pressure received from pressure supply 15 via supply port 16 to one or several consumers 1 via delivery port 19. The value of the delivered pressure depends upon the degree of stroke displacement of transmission link 9, which is in turn dependent upon the angle of rotation or actuating distance of operating element 12. Hence, the greater the angle of rotation or actuating distance of operating element 12, the greater the delivered pressure, up to supply pressure.
The delivered pressure present in valve system 14 acts upon the active surface of graduating piston 3 exposed thereto, producing a force within valve system 14 in opposition to the actuating force. Such pressure-induced counter force is further assisted by the biasing force of spring 7, as well as by the combined biasing forces of return spring 2 which restores graduating piston 3 and return spring 18 which restores valve body 17. These combined forces are transmitted to operating element 12 in a direction opposite the actuating force applied thereto via a control spring 4 in contact with a movable spring seat 5, and via the transmission link 9 engaged with spring seat 5.
When the operator wishes to maintain a desired angle of rotation or actuating distance of operating element 12, and thereby the corresponding value of the delivered pressure, the degree of actuating force applied to the operating element must be sufficient to overcome the pressure related force and the abovementioned aggregate of the spring biasing forces.
The description relating to the known valve systems discussed above also applies to operation and function of springs 2, 18 which restore graduating piston 3 and valve body 17 in the embodiment of FIG. 1, i.e., the combined spring-related biasing forces are low compared with the pressure-induced force in opposition to the actuating force in the depicted embodiment. The actuating force in the embodiment of FIG. 1 is therefore also essentially dependent upon the arrangement of the lever ratios and the pressure force, and further, in the embodiment, upon the spring force of the spring 7. By virtue of such arrangement, the force delivered by the spring 7 can be changed with relative ease, and hence the actuation force requirement of the system can therefore be readily changed by altering the spring force of spring 7.
This feature is especially significant when different circumstances require an adaptation of the actuation force requirement. Such circumstances may require an unaffected actuation force requirement when lever ratios are changed, in particular when the length of the actuating element is changed, or may conversely require a change in actuating force requirement when lever ratios remain unchanged.
The invention also finds utility in conjunction with valve systems in which only a slight pressure force occurs due to the small diameter of graduating piston 3 of valve system 14. Such systems are used, in particular, in applications allowing for compromises regarding the graduability of the pressure delivered by valve system 14, such as for example, in a pneumatic emergency braking circuit of an electrically controlled vehicle braking system. In such instances, spring 7 allows the actuation force requirement to be fixed for different lever ratios within a range of magnitude to which the operator is accustomed.
The spring force can be changed simply by exchanging the existing spring 7 for one with the desired force delivery. Alternatively, in an advantageous embodiment, spring 7 can be installed in an adjustable manner, an example of which is illustrated in the valve arrangement of FIG. 1. In the example shown, bearing element 10 is provided with a threaded neck 13 disposed around the passage of transmission link 9 therethrough. A spring seat 6 having inside threads for threadably engaging threaded neck 13 can be shifted longitudinally by rotation thereof. By virtue of the longitudinal shiftability of spring seat 6, the tension force of spring 7, and thereby its spring force, is continuously adjustable.
Further possibilities for the adaptation of the system to different circumstances are created through the selection or modification of the characteristic line of force/deflection of spring 7. Depending on the design of spring 7, it may have a linear or non-linear characteristic line of the force/deflection, with corresponding evolution of the actuating force acting upon the operating element 12. Often a progressive evolution of the actuating force is required. This can be achieved, or assisted in cases where control spring 4 is already progressive, through selection of spring 7 with a progressive force/deflection characteristic line.
Spring 7, which for purposes of illustration is conveniently shown in the form of a helical spring, can also have an entirely different configuration, for example provided in the form of an elastomer spring, similar to the control springs in the previously mentioned WABCO Westinghouse publications, which are incorporated herein by reference.
Turning now to FIG. 2, a differently configured system is shown, depicted from the perspective as viewed by the operator. A spring 30 is located alongside operating element 12. Bearing shaft 1, which is fixedly connected to operating element 12, acts upon spring 30 by intercalation of a cup ram 22 moved via a cam 23. Spring 30 can be adjusted by means of a spring seat 29 and an adjusting screw 27 a setting of which is maintained by a lock nut 28.
A valve system, designated generally by the numeral 20, is lever-operated in this case as described in the previously mentioned WABCO Westinghouse publication "Motorwagen-Bremsventil 461 295."
Operating element 12 in the depicted valve arrangement is used for simultaneous actuation of another device 26, which, in the depicted example of FIG. 2 is an electrical brake signal transmitter of an electrically controlled vehicle braking system. Such a brake signal transmitter is described, for example, in U.S. Pat. No. 4,818,036, entitled "BRAKING POWER TRANSMITTER," issued to Reinecke on Apr. 4, 1989, and which is incorporated herein by reference.
To actuate the other device 26, an additional cam 25 permanently connected to bearing shaft 11 is installed on same.
Depending on the particular application, the other device 26 may be different than that of the example shown without departure from the contemplated scope of the invention. Furthermore, several additional devices could also be provided, in which case bearing shaft 11 would be provided with corresponding cams for operation of same. Such arrangement, however, does not necessarily require that a special cam for every other device be provided on bearing shaft 11. Rather, it is possible for the devices to be placed at an angle to each other, and the cam, distributed over its circumference, provided with a special cam contour for each of these devices.
Reference numerals 21 and 24 designate rotary bearings of bearing shaft 11.
The explanations applicable to one figure also apply generally to the remaining figure, directly or in corresponding application, to the extent that the above details are not in conflict with one another.
Having described preferred embodiments of the invention with reference to the accompanying drawing, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims. | An arrangement for use with a valve system permits facilitated adaptation to conditions where modified lever ratios are desired while an actuation force requirement remains unaffected, or where a modified actuating force requirement is desired while lever ratios remain unchanged. In order to avoid or reduce costs associated with modification of the actuation force requirement of the valve system, a spring is provided which acts upon an operating element thereof, in addition to a pressure force, and codirectional therewith, against the actuating force in such manner that a predetermined actuating force requirement results. The invention finds particular significance in applications directed to vehicle braking systems. | 5 |
BACKGROUND OF THE INVENTION
The invention relates to a method for evaluating the field of vision. The invention furthermore relates to an apparatus for performing the method.
Known from WO 01/60 241 A1 are for instance a method and an apparatus for examining an eye, an image acquisition unit embodied as a camera and an illumination unit being used in conjunction with a computer-supported image evaluation. The illumination unit includes a light source, such as for instance a laser, and a deflection unit or scanning unit, by means of which the light beam from the light source is deflected two-dimensionally in a plane and at least some of the eye, for instance the surface of the retina, is scanned. The reflected light beam is detected by means of the image acquisition unit and a computer evaluates the acquired images, especially using optical coherence tomography (OCT), for representing planar images by means of an image generating device. The apparatus or the opthalmoscope includes closed control circuits with a motor control for an illumination lens for the purpose of automatic focus adjustment of an imaging lens. Moreover, the brightness of the illumination unit is adjustable for the purpose of attaining good contrast and good illumination of the eye to be imaged or of an area of the eye to be imaged.
Furthermore known is a method for examining field of vision, which method is based on representing a stimulus and is described in the publication “Ramachandran V. S., Rogers Ramachandran D.: Phantom Contours: A New Class of Visual Patterns that Selectively Activates the Magnocellular Pathway in Man. Bulletin of the Psychonomic Society, 2, 391 (1992)”. The method or depiction of the stimulus is known as “flicker defined form” and shall be referred to hereinafter as FDF.
The underlying object of the invention is to propose a novel method and an apparatus in order to efficiently evaluate the field of vision of a person and/or in order to detect in particular early signs of disease processes that can lead to limitations in the field of vision. The method and the apparatus should furthermore be embodied and/or optimized such that results for the field of vision examination are combined with results of a structural evaluation of the optic disc in an eye in order to increase diagnostic capability, especially for diseases such as glaucoma that lead to both functional changes in the field of vision and to structural changes in the optic disc. The underlying object of the invention is furthermore to refine the method and the apparatus such that the examination and/or evaluation of the field of vision can be performed in a simple manner and/or such that confidence in decision-making is optimized. Moreover, rapid and reliable testing and/or evaluation should be possible, subjective evaluations being avoided.
SUMMARY OF THE INVENTION
The inventive method and the apparatus enable complete and especially automatic evaluation using a computer-controlled system for representing FDF stimuli for efficient determination of visual function. The invention discloses a novel method and a novel apparatus and makes possible efficient evaluation in particular of the field of vision of a person in order to detect in particular early signs of disease processes that can lead to limitations in the field of vision. In accordance with the invention, results of the field of vision examination are combined with results of the structural evaluation especially of the optic disc in order to increase diagnostic capability, especially for diseases such as glaucoma that lead to both functional changes in the field of vision and to structural changes in the optic disc.
In accordance with the invention, a method for eye examination or a device or system embodied therefor, such as perimeter, confocal laser scanning system, OCT interferometer, or scanning laser opthalmoscope is combined with the FDF method or an FDF device. Simultaneous acquisition and representation and/or examinations and/or evaluations of functional and/or structural changes in the eye are made possible in a surprisingly simple manner by using the inventive combination and/or integration creating a single method and/or a single apparatus.
The FDF stimulus comprises and/or uses and/or occurs with an image generating unit, such as a monitor or cathode ray tube (CRT), flat screen, projection device, or the like, and specifically especially with the same common image generating unit. The application of the FDF examination using the inventive method and/or by means of the inventive apparatus reliably enable the use of FDF perimetry in order to perform examinations of the eye, especially for glaucoma, optic nerve and/or retinal disease and abnormalities, eye disease due to diabetes, and neurological disease and abnormalities. Furthermore, in accordance with the invention, patients with low vision, patients with special needs, and some patients with learning disabilities can be examined according to the inventive method and/or with the inventive apparatus.
In one special embodiment of the invention, a method and/or an apparatus for determining an artifact and/or the beginning of a stimulus for correcting or detecting an artifact and/or for stimulus beginning artifact correction are used. An FDF stimulus comprises and/or uses an image generating unit (CRT display, LCD display, projection device, or the like) on which numerous circular objects or points are displayed against a solid background. The recordable surface of the image generating unit is filled with these points in a preferred manner and/or is at least nearly essentially filled with these points and/or is completely filled with these points. The aforesaid points are classified in two categories, specifically background points and target points. The background points preferably cover the majority of the visible display. One circular area of the display unit and/or the image generating unit is intended for representing the stimulus and the points that are disposed and/or located inside the stimulus area are classified and/or categorized as target points.
During the representation of the FDF stimulus, which hereinafter shall be referred to only as FDF stimulus, the points move between two brightnesses or intensity values at a fixed frequency. The first level is a fixed luminosity value above the background luminosity. And the second brightness is the same luminosity value below the background luminosity. However, it is important to note that during the stimulus representation the background points and the target points are in phase opposition. For instance, when the target points are brighter than the background luminosity, the background points are darker than the background luminosity and vice versa.
Another special embodiment of the inventive method and/or apparatus makes it possible to evaluate the fatigue of the person being examined by using a real-time focusing monitor. While the FDF examination is being performed, targets are represented at different locations relative to the optical axis of the instrument. In order to support the fixed gaze or focusing on this point, a small black point is provided (focusing target). In addition, a means for verifying the correctness of the focusing during the period in which the target is represented is provided so that the coordinates of the different target eccentricities are correct.
This verification is provided by an image acquisition unit, such as a small CCD camera, that observes the examined eye of the person either directly or via a beam splitter that is arranged in the optical axis between the person and the display. The images are processed by the computer, which uses algorithms to determine the point of the fixed gaze of the person and/or to detect the correct focusing. This is done by identifying characteristic structures in the eye, for instance the pupil, and by continuously tracking the position of this structure during the FDF examination.
This tracking is performed by analyzing the image of the image generating unit or CCD camera with the computer. When the computer determines that the person was not focused during the target representation, or when this is determined by means of the computer, the results of such an acquisition and/or representation are discarded.
In addition, information regarding the degree of fatigue of the person can be derived from the focus loss rate. This information can be used to evaluate the quality of the examination results, or to indicate that the person needs a break from the examination.
In another special embodiment of the method and/or apparatus, it is possible to evaluate a patient's reliability by using continuous reaction time monitoring. The inventively developed and/or proposed method and/or the apparatus used for performing said method makes it possible to continuously monitor a patient's reaction time to the representation of the FDF stimulus.
The reaction time is measured as the time, especially in milliseconds, between a target representation being initiated and the patient depressing the response button. This is monitored for every target representation during an examination, and a concurrent mean is calculated, together with confidence limits. Each response that falls outside the 95th percentile is evaluated either as a false positive (<) or an unreliable response (>).
One special use of this data is comprised in establishing individual reaction time characteristics and patient-related confidence limits in order to determine the probability of whether a response is a false positive response. This information can then itself be used to establish reliability parameters.
In another embodiment according to the method and/or with the apparatus there is a boundary field examination. Adding light sources, especially LEDs, that are arranged physically and/or optically especially in the horizontal boundary field results in the unique and/or special ability to measure and/or evaluate especially fitness for driving or possibly special neurological areas.
In one special refinement and/or embodiment of the method and/or apparatus, these are embodied for controlling an increased brightness resolution. Standard graphics card technology provides 2 8 , or 256 levels of brightness, for each of the red, green, and blue color channels. A technique was developed in which the one monochrome screen (CRT, LCD, or a projection device) uses two of the color channels in order to provide brightness levels with up to 2 16 , or 65536, brightness levels.
The method and/or the apparatus preferably use especially the green and red channels of an RGB signal with 8 bits brightness control per channel such that the resultant control is a monochrome channel with 16 bits intensity or brightness regulation. The green channel is used as the 8 bits with the greatest significance. Therefore one level of the green channel is responsible for a brightness increment of 1/256 of the maximum. The red channel is used as the 8 bits with the least significance. Therefore one level of the red channel is responsible for a brightness increment of 1/65536 of the maximum. The resulting two signals are added with the resulting intensity or brightness control function:
Brightness
=
maximum
brightness
·
[
G
256
+
R
65536
]
where G is the green signal level, the values of which range from 0 to 255, and R is the red signal level, the values of which range from 0 to 255.
Although this technique is responsible for a theoretical maximum of 65536 brightness levels, in practice the number of control levels that can be attained is significantly less. At some time the change in the signal level of the combined brightness control signal will become smaller than the noise that is always present in the system.
The advantage of this technique is that when introduced, the controlling software can be configured to provide any number of brightness control levels, ranging from 2 8 to 2 16 .
This is attained in that the most significant 8 bits of the necessary brightness value are arranged in the green color channel. The other bits of the necessary brightness value are arranged in the most significant bits of the red channel.
Green
=
(
Brightness
16
⋀
1111111100
000000
B
)
11111111
B
Red
=
(
Brightness
16
⋀
0000000011111111
B
)
x
11111111
B
In another embodiment, an adaptive step threshold algorithm (ASTA) is used that is a threshold estimating algorithm that uses a few special techniques.
Each target position can be assigned to different strategies of steps. A rapid sequence can be assigned to each position that passes through in excess of a single threshold value within the 95th percentile of the age-related normal values for the stimulus position. The start value for each psychophysical step threshold value estimating algorithm is set by its neighbor and develops from four initial set points that all pass through a complete step (4-2-2)-sequence. The start value for all of these secondary points is a pre-specified number of decibels below the adjacent threshold. A 2- 2 step is used, but if the first threshold value excess seen is climbing and is within the 95th confidence interval, then the threshold value estimate has taken place. Age-related normal data are formed in that non-linear methods are used for each stimulus site. Non-linear confidence limits are also established. This provides increased accuracy for the threshold estimation pattern and for data analysis. The speed and accuracy of the algorithm can be changed by adapting the confidence interval permitted for a rapid sequence. For instance, the speed will increase and accuracy will decrease if larger confidence limits are used for the criterion of the rapid sequence. There are two types of examination: i. First ASTA (iASTA), which is used for establishing initial data. ii. ASTA that uses information from preceding fields (iASTA or ASTA, an individual initial field, or the mean of a plurality of initial fields) in order to advance the step algorithm efficiently. iASTA uses a complete threshold value determination strategy. ASTA then uses the pre-determined initial data to set the start values for each stimulus position and thus reduces the examination time.
Moreover, a hop limit strategy is preferably employed and/or used. Given the nature of the random point background, when the FDF stimulus is produced it is important to limit the change in contrast between successive representations. Limits that are especially based on empirical data are provided for each contrast step and a method for recording these maximum permissible steps is employed in the threshold value estimation algorithm (preferably ASTA). The limits are determined empirically and vary with respect to and/or as a function of eccentricity and defect depth. For instance, the limit for a stimulus contrast of 24 dB that is represented at an eccentricity of 3 degrees is or is pre-specified at 4 dB.
In another special embodiment, automatic control correction is used to compensate for deterioration, especially of the CRT phosphorus. The FDF instrument or the FDF unit requires that the brightness of the represented stimulus remains correctly adjusted. However, if a CRT is used, the luminosity of the phosphorus decreases with time for a specific control setting.
Similarly, the luminosity of an LCD unit or the brightness of a projection device or in general of the image generating unit can change with time.
The FDF unit includes a circuit that provides a means for measuring the brightness of the light generated by the image generating unit, such as CRT or LCD unit or projection device. The FDF unit periodically measures the brightness of the light generated by the image generating unit across its entire control range. This behavior is automatically corrected by monitoring the luminosity of the image generating unit and by controlling the control value using a microprocessor.
The circuit includes two photodiodes that scan the light from the image generating unit, such as the CRT or LCD or projection device. The signal from each photodiode controls a current to the voltage transformer, then an amplifier with programmable amplification. The programmable amplification is used to compensate individual sensitivities of the photodiodes. The prepared signal is then scanned with an ADC. At the time of production, a table is generated in order to provide a context between the ADC value and cd/m 2 . The circuit essentially provides an instrument with a built-in light meter.
Obviously aging of the photodiodes themselves over time can cause changes in the displays of the photodiodes. To prevent this, two photodiodes are used as described in the foregoing. The measurement of luminosity is not accepted unless both photodiodes produce similar displays. Otherwise the user is informed that the apparatus requires testing or maintenance.
In one special embodiment of the invention, a method is provided for determining the correct position of the optic disc in the field of vision and its use. In order to be able to precisely determine the area of the field of vision that corresponds to a specific section of the optic disc and vice versa, it is important to know the precise relative position of the optic disc to the fovea. In one test, for instance with a retina tomograph, the patient focuses on a focusing target that has a fixed and known position relative to the optical axis of the instrument. All images obtained are arranged in the center about the optical axis of the instrument. In this way the center position of the optic disc within an obtained image permits the precise determination of the relative position of the optic disc to the fovea.
With this information it is possible
either to represent the stimulus at the correction positions during the field of vision examination such that a certain area of the field of vision corresponds precisely to a certain section of the optic disc; or to plot the field of vision examination results after the field of vision examination such that certain areas of the field of vision are correctly assigned to certain sections of the optic disc.
In the inventive apparatus, in addition to the combination and/or integration of the FDF unit in the apparatus or the device with which the structures of the eye are examined and/or detected and/or evaluated, the method measures or functions explained in the foregoing are combined individually or a few at a time or all of them are combined and are realized by means of the computer, whether as hardware or software. The invention moreover includes the use of the inventively proposed and/or embodied apparatus.
Special embodiments and refinements of the invention, specifically of both the method and the apparatus, are depicted in the drawings and described in the following, but this shall not constitute any limit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 provides diagrams of the background points and the target points of the image generating unit for determining an artifact;
FIG. 2 depicts the optic disc and the field of vision;
FIG. 3 depicts an image of the optic disc corresponding to the structural classification;
FIG. 4 provides representations of the field of vision results;
FIG. 5 is another representation of the field of vision results.
DETAILED DESCRIPTION OF THE INVENTION
Determining an artifact or the stimulus beginning for correcting or detecting an artifact shall be explained using FIG. 1 . An FDF stimulus uses the image generating unit, on which a plurality of small circular objects or points are displayed on a solid background. The recordable and/or useable surface of the image generating unit is preferably at least almost completely filled with such points. These points are classified in two categories, specifically background points and target points. The background points preferably cover the majority of the visible display unit. A circular area in the display unit is provided for displaying the stimulus and those points that are disposed within the area of the stimulus are classified as target points. During the representation of the FDF stimulus, the points move back and forth between two brightness or intensity values at a pre-specified fixed frequency. The first step or a first level is an established brightness or luminosity value above the background brightness or background luminosity. The second brightness or intensity has the same value of luminosity or brightness below the background luminosity. It should be noted that the background points and the target points are in phase opposition when the stimulus is being represented. If e.g. the target points are brighter than the background luminosity, then the background points are darker than the background luminosity and vice versa. If the background points and the target points are now in phase, the display unit or image generating unit seems to flicker homogeneously. However, if the background points and target points are in opposing phases, a shadow-like ring appears around the perimeter and/or outer area of the target point area.
When an FDF stimulus is represented, the sudden change in the stimulus point from being in-phase with the background points to a 180° phase shift results in an artifact, the stimulus temporarily appearing brighter than the surrounding point field. The basis for the artifact is physiophysical in nature and is not based on abnormal or anormal brightness levels. The same artifact also occurs with a shift in stimulus.
The methods or the technique that is used to correct this artifact includes the gradual transition in the target point reversal from in-phase with the background points to phase-shifted. Starting with the reversal of the target points being in-phase with the background points, the amplitude of the target point reversal is reduced in a plurality of steps until the amplitude reaches zero. The amplitude of the target points then increases when the peak strength is in phase opposition to the background points.
The progression is depicted in the diagram in FIG. 1 . The first wave 1 . 1 represents the cycle of the background points between values for the monochrome luminosity or between monochrome brightness values in a symmetrical manner about the mean luminosity or mean brightness. The next four waves 1 . 2 to 1 . 4 depict the progression of the brightness for the target points or target point luminosity from in-phase to 180° phase-shift relative to the luminosity or brightness of the background points.
FIG. 2 explains a special embodiment of the invention, specifically a structure-function analysis, in greater detail. A number of diseases of the posterior segment of the eyeball, for instance glaucoma, lead both to changes in the field of vision (functional changes) and to changes in the structure of the optic disc (structural changes). It is important to be able to evaluate the function and the structure in order to diagnose such diseases or to detect the progression of such diseases.
The inventive combination of the FDF unit, for instance an FDF perimeter, and a device or an apparatus with which structures of the eye, especially the optic disc structure, are examined and/or detected and/or evaluated, for instance a retina tomograph, makes possible a unique combined analysis of structure and function. This is based on the known assignment of certain segments, especially the optic disc, to certain areas of the field of vision.
The right-hand side of FIG. 2 depicts the optic disc divided into six different segments 1 through 6 and the left-hand side depicts the field of vision divided into six different areas 11 through 16 . Segment 1 corresponds to the area 11 , segment 2 corresponds to area 12 , etc. The optic disc segments and the field of vision areas that correspond to one another have the same coding, especially color coding. Thus for instance segment 1 is coded red and so is area 11 , and furthermore segment 2 is coded green, as is area 12 , and the other segments and areas that are assigned to one another each have matching color coding. The segments of the optic disc and the areas of the field of vision assigned to them can also be coded with graphic patterns, as is depicted in black and white in FIG. 2 . Furthermore, the number of segments and areas can be pre-specified according to the requirements.
Each segment of the optic disc and each area of the field of vision is divided into one of two or more categories. For instance, one set can have three categories: “within normal limits”, “at the limit”, and “outside normal limits”. The methods explained in the following are used in order to represent these results to the person performing the examination, in particular the physician.
A first method is explained using FIG. 3 , in which an image of the optic disc 20 is depicted and is divided into two or more segments; in this case it is divided into eight segments. Two rings 21 , 22 that are divided into the same segments are superimposed. The inner ring 21 displays the results of the structural classification for every segment of the optic disc using a color code, for instance green G for “within normal limits”, yellow Y for “at the limit”, red R for “outside normal limits”. The outer ring uses the same color code to display the classification results for the area of the field of vision that corresponds to a segment of the optic disc.
Explained in FIG. 4 is a second method, the field of vision results being depicted using the display of an image having the field of vision results for each stimulus position. The entire field of vision is divided into two or more areas that correspond to certain segments of the optic disc. The background for each field of vision area is color-coded, as explained in the foregoing, corresponding to the classification results for the optic disc structure that corresponds to this area.
In addition, in a third method the two measurements provided by the structural evaluation and the field of vision evaluation can be combined with respect to estimating normal, age-related ganglion cell density. This can be plotted by the clockwise positions of optic disc segments, in a manner similar to the known TSNIT plot, with the ganglion as the ordinate, and both measurements of structure and function plotted per segment on the abscissa.
Finally, in a fourth method in accordance with FIG. 5 , the field of vision results can be superimposed in an image of the optic disc such that each optic disc segment is color-coded in accordance with the field of vision results in its corresponding area of the field of vision.
The special features and refinements explained using the drawing are handled for the area of the optic disc. In the framework of the invention, these special features and refinements can be provided for other areas of the eye, such as the macula, or for other areas of the retina, analogous to those covered in the foregoing. | The invention relates to a method for assessing the field of vision, wherein FDF stimuli are produced and detected by a person using the at least one eye to be examined. The invention is based on the object of providing a novel method and a device in order to efficiently assess the field of vision of a person and/or in order to recognize early signs of disease processes, which can lead to limitations in the field of vision. For this purpose, the invention provides that the production of the FDF stimuli is carried out by utilizing a computer-controlled system for the efficient determination of the vision and that the respective FDF stimulus is generated by utilizing an imaging device. | 0 |
This nonprovisional application is a continuation of International Application No. PCT/EP2013/055239, which was filed on Mar. 14, 2013, and which claims priority to German Patent Application No. 10 2012 005 054.2, which was filed in Germany on Mar. 15, 2012, and which are both herein incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for projecting a user interface, provided for a screen of a mobile device, of an application program, running in the mobile device, onto a screen of an infotainment system disposed in a vehicle.
The invention relates further to a mobile device having a screen, an interface unit, and an application program displaying a user interface on the screen, whereby the mobile device is designed to work together with an infotainment system, installed in a vehicle and having a screen, such that a data interface between the mobile device and the infotainment system is formed via the interface unit.
The invention relates, moreover, to an infotainment system having a screen and an interface unit, whereby the infotainment system is designed to work together with a mobile device, which has a screen and in which an application program displaying a user interface on the screen of the mobile device runs, such that a data interface between the mobile device and the infotainment system is formed via the interface unit.
DESCRIPTION OF THE BACKGROUND ART
It is prior in the art to integrate an application program (also called an application) of a mobile device into an infotainment system of a vehicle. To this end, the screen content of the mobile device is transmitted via a data interface to the infotainment system screen installed in the vehicle. The technology MirrorLink™ from the Car Connectivity Consortium, Beaverton, USA, for example, is suitable for the transmission.
The appearance of a user interface of an application program varies according to the optical properties of the selected screen. These properties include, for example, the screen's resolution and pixel density. The resolution can be expressed by the number of pixels horizontally (horizontal resolution) and vertically (vertical resolution). In this case, a pixel is understood to be a surface element of the screen necessary for displaying a color value. A pixel can be made up of a plurality of monochromatic image points, for example, from a red, green, and blue image point, in order to be able to display any color values. The pixel density can be expressed by the number of pixels per inch horizontally (horizontal pixel density) and vertically (vertical pixel density). The screen size can be expressed by the (visible) horizontal length and the (visible) vertical length of the screen.
The different appearances of the user interface of the application program pose difficulties for the application program developer, if the application program is to be suitable for different screens. The developer must take into account the different optical properties of the screens to avoid undesirable distortions, for example. Allowing the developer to work with a virtual pixel, namely, the density-independent pixel, is a known approach for freeing him from the specific optical properties of the different screens. The developer programs the user interface of the application program in units of these virtual pixels and leaves it to the screens to display the user interface correctly.
The introduction of density-independent pixels, however, does not assure that the screen content of a mobile device is displayed on the screen of the infotainment system in a manner suitable for the driver of a vehicle.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide a method to assure a display suitable for a driver of a vehicle of a user interface of an application program, running in the mobile device, on a screen of an infotainment system disposed in the vehicle. The invention further has an object of providing a mobile device and an infotainment system with which the method of the invention can be carried out.
The object is achieved in an embodiment according to the invention with a method in that the screen size of the infotainment system in the unit of comparable size is determined in the infotainment system, the screen size of the infotainment system is transmitted via a data interface to the mobile device, the user interface size of the application program, running in the mobile device, in the unit of comparable size is determined in the mobile device, the screen size of the infotainment system is compared with the user interface size of the application program running in the mobile device, and depending on the comparison, a decision is made in the mobile device whether and, if so, which image data concerning the user interface are transmitted from the mobile device via the data interface to the infotainment system.
The comparable size is used uniformly in both the mobile device and the infotainment system to express the size of the user interface (user interface size) or the screen (screen size) of the infotainment system and to use this for the comparison. Thus, independent of the mobile devices and infotainment systems used in the specific case, it can be assured in a simple way that the projection of the display of the mobile device onto the screen of the infotainment system of the vehicle will be of a sufficient size to be read and operated easily by the driver. In addition, the programmer of the application program is unburdened, because he does not need to be concerned about the devices in which his application program will run. He specifies only one size in the unit of comparable size, which the screen of the device to be employed should have. A further advantage of the method of the invention is that the application program can be tested with a simple test setup as to whether it responds correctly if the screen size is smaller than the necessary screen size.
The image data, completely representing the user interface, are preferably transmitted from the mobile device via the data interface to the infotainment system, if the comparison shows that the screen size of the infotainment system is not smaller than the user interface size of the application program running in the mobile device. Thus, the user interface can be displayed on the screen of the infotainment system without content-based limitations and is available to the driver.
In an embodiment, the image data, modifying the user interface, are transmitted from the mobile device via the data interface to the infotainment system, if the comparison shows that the screen size of the infotainment system is smaller than the user interface size of the application program, running in the mobile device, and the application program has available a modified user interface for the screen size of the infotainment system. The availability of modifying image data can prevent the situation that the user interface is displayed either not at all or in insufficient quality on the infotainment system screen. The programmer of the application program expediently takes into account even during the programming the different layout classes in that he makes available a suitable user interface for each layout class. A layout class in this case represents screens whose optical features fall within certain intervals. Therefore, a variety of different screens is not considered or taken into account, but only a rough classification is made. Thus, a first layout class can be provided, for example, for smartphones, a second layout class for tablet PCs, and a third layout class for infotainment systems, so that the programmer makes available three different versions for a user interface of the application program. The assignment of a screen to a layout class occurs expediently via the size of the screen in the unit of comparable size.
In an embodiment no image data concerning the user interface are transmitted via the data interface to the infotainment system, if the comparison shows that the screen size of the infotainment system is smaller than the user interface size of the application program, running in the mobile device, and the application program does not have a modified user interface available for the screen size of the infotainment system. This prevents the distraction of the driver from traffic by a distorted or poorly readable screen content.
Moreover, the object is achieved according to an embodiment of the invention with a mobile device of the aforementioned type in that the mobile device is designed to receive via the data interface from the infotainment system the screen size of the infotainment system in the unit of comparable size, to determine the user interface size of the application program, running in the mobile device, in the unit of comparable size in the mobile device, to compare the screen size of the infotainment system with the user interface size of the application program running in the mobile device, and depending on the comparison, to decide whether and, if so, which image data concerning the user interface are transmitted from the mobile device via the data interface to the infotainment system.
The advantages of the mobile device of the invention emerge from the aforementioned advantages of the method of the invention, because the mobile device is designed to work together with a suitable infotainment system so that they can carry out the method of the invention.
In order to display the user interface without content-based limitations on the screen of the infotainment system and to make it available to the driver, the mobile device is expediently designed to transmit the image data, completely representing the user interface, from the mobile device via the data interface to the infotainment system, when the comparison shows that the screen size of the infotainment system is not smaller than the user interface size of the application program running in the mobile device.
Advantageously, the mobile device is designed to transmit the image data, modifying the user interface, from the mobile device via the data interface to the infotainment system, if the comparison shows that the screen size of the infotainment system is smaller than the user interface size of the application program running in the mobile device, and the application program has a modified user interface available for the screen size of the infotainment system. The availability of modifying image data can prevent the situation that the user interface is displayed either not at all or in insufficient quality on the infotainment system screen.
In order to prevent the driver from being distracted from traffic by a distorted or poorly readable screen content, in an advantageous embodiment the mobile device is designed not to transmit any image data concerning the user interface via the data interface to the infotainment system, if the comparison shows that the infotainment system screen size is smaller than the user interface size of the application program running in the mobile device, and the application program does not have a modified user interface available for the infotainment system screen size.
The object is achieved further according to an embodiment of the invention with an infotainment system of the aforementioned type in that the infotainment system is designed to determine the infotainment system screen size in the unit of comparable size and to transmit this via the data interface to the mobile device and to receive image data provided by the mobile device and concerning the user interface via the data interface.
The advantages of the infotainment system of the invention emerge from the aforementioned advantages of the method of the invention, because the infotainment system is designed to work together with the mobile device of the invention such that they can carry out the method of the invention.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
FIG. 1 shows a schematic arrangement of a mobile device of the invention and of an infotainment system of the invention;
FIG. 2 shows a flowchart of the method of the invention; and
FIG. 3 shows a schematic arrangement of the screens of the mobile device and infotainment system of FIG. 1 .
DETAILED DESCRIPTION
FIG. 1 shows an infotainment system 20 installed in the center console of a vehicle 10 . Infotainment system 20 is a network of a plurality of devices that provide the driver with various information and/or functions. Such devices include, for example: a radio, CD (compact disc), DVD (digital versatile disc), telephone, navigation device, and traffic telematics device.
Infotainment system 20 has a control unit 30 , a memory unit 40 , a screen 50 , and an interface unit 60 .
Memory unit 40 in the present exemplary embodiment can include an internal memory 70 , permanently integrated into infotainment system 20 , and an optional external memory 80 . The optional external memory 80 can be, for example, an SD card (SD: secure digital) that can be inserted in a suitable slot or a USB stick (USB: universal serial bus).
The size of screen 50 in the unit of comparable size is stored in memory unit 40 . In the present case, the comparable size is defined as: one by a hundred of an arbitrary length unit (LE) in the horizontal direction, and one by a hundred of the arbitrary length unit in the vertical direction. In other words, there are 100 virtual pixels per length unit in both the horizontal and vertical direction. A centimeter can be selected, for example, as the arbitrary length unit.
Screen 50 (also see FIG. 3 ) has a resolution of 800 real pixels in the horizontal direction and 400 real pixels in the vertical direction. The horizontal dimension (width) constitutes two length units and the vertical dimension (height) one length unit. This results in a pixel density of 400 pixels per length unit both in the horizontal and vertical direction. For the size of screen 50 in the unit of comparable size, this comes down to only the width and height of screen 50 . The size in the unit of comparable size, i.e. device independent pixel, therefore is 200 units in the horizontal direction and 100 in the vertical direction, or stated differently: (200×100).
A device independent pixel is a physical unit of measurement based on a co-ordinate system held by a computer and represents an abstraction of a pixel for use by an application that an underlying system then converts to physical pixels.
A data interface 90 for exchanging data to external devices, for example, to a mobile device 100 , is made via interface unit 60 . Data interface 90 in the present case is designed so that it supports the standard MirrorLink™.
Control unit 30 can exchange data bidirectionally with memory unit 40 . Control unit 30 reads from memory unit 40 , for example, the size of screen 50 in the unit of comparable size.
Control unit 30 can exchange data bidirectionally with screen 50 . For example, control unit 30 sends image data to screen 50 , which thereupon displays a screen content corresponding to the image data. Screen 50 is made as a touchscreen, so that the user can input control commands into infotainment system 20 by touching the screen surface. These control commands are then transmitted to control unit 30 .
Control unit 30 can exchange data bidirectionally with interface unit 60 . For example, control unit 30 sends the size of screen 50 in the unit of comparable size via interface unit 60 and data interface 90 to mobile device 100 .
Mobile device 100 has a control unit 110 , a memory unit 120 , a screen 130 , and an interface unit 140 .
Memory unit 120 in the present exemplary embodiment has an internal memory 150 , permanently integrated into mobile device 100 , and an optional external memory 160 .
The program code of an application program 170 is stored in memory unit 120 , in the present case in internal memory 150 .
Screen 130 (also see FIG. 3 ) has, for example, a resolution of 1000 real pixels in the horizontal direction and 2000 real pixels in the vertical direction. The horizontal dimension (width) constitutes one length unit, and the vertical dimension (height) also one length unit. This results in a pixel density of 1000 pixels per length unit in the horizontal direction and 2000 pixels per length unit in the vertical direction. The real pixels therefore are much closer together than in screen 50 of infotainment system 20 . For the size of screen 130 in the unit of comparable size, this comes down to only the width and height of screen 130 here as well. The size in the unit of comparable size therefore is 100 units in the horizontal direction and 100 units in the vertical direction, or stated differently: (100×100).
Data interface 90 for exchanging data to infotainment system 20 is set up via interface unit 140 . Of course, data interfaces to other devices can also be set up via interface unit 140 . Only data interface 90 is of interest in the present case, however.
Control unit 110 can exchange data bidirectionally with memory unit 120 . Control unit 110 reads from memory unit 120 , for example, application program 170 in order to execute it.
Control unit 110 can exchange data bidirectionally with screen 130 . For example, control unit 110 sends image data to screen 130 , which thereupon displays a screen content corresponding to the image data, for example, a user interface of application program 170 . Screen 130 is also made as a touchscreen, so that the user can transmit control commands to mobile device 100 by touching the screen surface. These control commands are then transmitted to control unit 110 .
Control unit 110 can exchange data bidirectionally with interface unit 140 . For example, control unit 110 receives the size of screen 50 of infotainment system 20 in the unit of comparable size via data interface 90 and interface unit 140 from infotainment system 20 . In addition, control unit 110 can send data, for example, the image data concerning the user interface, via interface unit 140 and data interface 90 to infotainment system 20 .
A comparison of the size of screen 130 (or the user interface) with the size of screen 50 of infotainment system 20 is carried out in control unit 110 of mobile device 100 and the decision is made whether and, if so, which image data are sent to infotainment system 20 .
The method of the invention will be described in greater detail with use of FIG. 2 .
In a step 200 , control unit 30 of infotainment system 20 determines the size of screen 50 of infotainment system 20 in the unit of comparable size.
In a step 210 , control unit 30 transmits the size of screen 50 of infotainment system 20 in the unit of comparable size via interface unit 60 and data interface 90 to mobile device 100 .
In a step 220 , control unit 110 of mobile device 100 determines the user interface size of application program 170 running in mobile device 100 in the unit of comparable size. This occurs expediently in such a way that application program 170 has available the user interface size in the unit of comparable size and provides this to control unit 110 , for example, after control unit 110 has sent a request signal to application program 170 .
In a step 230 , control unit 110 compares the size of screen 50 of infotainment system 20 in the unit of comparable size with the user interface size of application program 170 in the unit of comparable size. The comparison result is thereupon evaluated in a step 240 .
In step 240 , control unit 110 decides whether and, if so, which image data, concerning the user interface, are transmitted by mobile device 100 via data interface 90 to infotainment system 20 .
If the comparison shows that the screen size of infotainment system 20 is smaller than the user interface size of application program 170 , running in mobile device 100 , and the application program does not have any modified user interface available for the screen size of infotainment system 20 , the method ends in a step 250 . Expediently, control unit 110 sends a communication to control unit 30 of infotainment system 20 that no image data are transmitted for this application program 170 . Then, control unit 30 can control screen 50 such that the user, particularly the driver, is informed that application program 170 is not available in infotainment system 20 or the user interface of application program 170 is not available on screen 50 of infotainment system 20 .
If the comparison shows that the screen size of infotainment system 20 is smaller than the user interface size of application program 170 running in mobile device 100 , and application program 170 has a modified user interface available for the screen size of infotainment system 20 , then control unit 110 transmits image data modifying the user interface, which control unit 110 receives in a step 260 from application program 170 , from mobile device 100 via data interface 90 to infotainment system 20 . The image data of the modified user interface are stored in application program 170 in a layout class. Application program 170 can also have a number of layout classes available.
In a step 270 , the image data are transmitted from mobile device 100 via data interface 90 to infotainment system 20 .
In a step 280 , the image data are sent from control unit 30 to screen 50 , whereby the image data are converted optionally into suitable control signals in control unit 30 .
In a step 290 , a screen content, which is displayed on screen 50 , is generated from the image data or the control signals.
FIG. 3 shows screen 130 of the mobile device and screen 50 of infotainment system 20 .
Screen 130 of the mobile device in the present exemplary embodiment corresponds to the user interface of application program 170 . However, the user interface can also be larger or smaller than screen 130 .
The comparison in the unit of comparable size shows here (see the description to FIG. 1 ) that the user interface size (100×100) is not greater than the screen size (200×200) of screen 50 , because the condition “not greater than” is met both for the widths (100<200) and for the heights (100=100). Thereby, the user interface of the application program can be displayed completely on screen 50 of infotainment system 20 as image 300 , although the resolution and pixel density of screen 130 of mobile device 100 are greater than the resolution and pixel density of screen 50 of infotainment system 20 .
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims. | A method for projecting a user interface of an application program provided for a screen of a mobile device is provided onto a screen of an infotainment system arranged in a vehicle. The user interface can be displayed in a manner suitable for the driver of the vehicle if the screen size of the infotainment system is determined in the infotainment system. The screen size is transferred to the mobile device via a data interface, the user interface size of the application program running in the mobile device in the unit of the comparable size is determined in the mobile device. The screen size of the infotainment system is compared with the user interface size of the application program and a decision is made on the basis of the comparison, which image data is transferred from the mobile device to the infotainment system via the data interface. | 6 |
FIELD OF THE INVENTION
This invention relates to porphyrinogenic resin systems and methods for their manufacture, and to coating compositions and methods involving such resins. The invention is particularly concerned with anti-corrosion coatings, derived from such resins.
BACKGROUND OF THE INVENTION
In International Patent Application No. PCT/AU91/00298, we described how the condensation of a beta-unsaturated aldehyde, especially crotonaldehyde, and pyrrole can give rise to a monomeric product which contains porphyrin-bearing unsaturated substituents. This monomeric material, which we referred to as a “polymerisable porphyrin”, then readily polymerises to produce polymeric product.
Polymers made from the monomeric material, or copolymers formed from the polymerisable material and at least one other polymerisable monomer of a known type, can be used in the production of films, coatings and other structures.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide polymerisable resins and/or compositions derived from them which have improved properties such as, for example, improved anti-corrosion properties.
We have found that this and other objectives can be achieved by reacting a cyclic ketone with pyrrole or an N-alkyl pyrrole, either of which may contain one or more suitable substituents, or a mixture of two or more such pyrroles.
Thus according to one aspect of the present invention, there is provided a polymerisable resin comprising a porphyrinogenic ring system produced by the reaction of:
(a) one or more compounds selected from the group consisting of pyrrole and N-(lower)alkyl pyrroles, any of which may be ring substituted with one or more non-deleterious substituents, with
(b) a C 4 -C 6 saturated alicyclic ketone which is capable of reacting with the 2 or 5 position of the pyrrole ring.
DETAILED DESCRIPTION OF THE INVENTION
The reaction generally requires the presence of an acid catalyst, which is selected to suit the particular chosen reagents (a) and (b). The catalyst may be an inorganic acid, or an organic acid, such as acetic or propionic acid, or an acid anhydride, such as phthalic anhydride. Organic acids which contain unsaturated groups may be used. These acids may become incorporated into and provide functional groups in the resin product, as well as providing a catalytic function. Acids containing vinyl groups, such as acrylic acid, or triple bonds, such as acetylene dicarboxylic acid, are especially useful in this regard.
Inorganic acids, especially the hydrohalic acids, such as hydrochloric acid, may also be used either alone or with an organic acid, as described above. Mixtures of an inorganic acid, e.g. HCl, and an unsaturated aliphatic aldehyde, such as acrolein or crotonaldehyde, are also effective catalysts.
Where the reactant (a) is or includes an N-alkylpyrrole, the acid catalyst also has the important function of removal of the alkyl group to allow reaction of the dialkylated pyrrole intermediate with the ketone to give the porphyrinogenic ring system. Hydrochloric acid is especially useful in this regard, particularly when used with cyclohexanone or other cyclic ketones which act as co-solvents for the (normally immiscible) aqueous acid and N-alkylpyrrole.
The preferred cyclic ketone is cyclohexanone.
The extent of the reaction may be controlled by adding one or more suitable reagents which effectively terminate the polymerisation. For example, addition of a C 1 -C 8 aliphatic alcohol, such as butanol, results in “end-capping” of the carboxyl group of an organic acid catalyst. When an inorganic acid catalyst is used, addition of a saturated cyclic monoether, such as tetrahydrofuran (THF), results in ring opening of the cyclic ether by the acid, and the acid is thereby removed from the reaction system. For example, when the catalyst is HCl, reaction with THF results in the formation of 1-chlorobutanol.
The term “porphyrinogenic ring system” as used herein means a porphyrinogen or porphyrinogen-like ring system comprising 5-membered heterocyclic rings linked in a macrocyclic ring structure by linking groups. The linking groups have unsaturated side chains and π-covalent bonding is formed between the macrocyclic ring and the double bonds of the side chains. The porphyrinogenic ring system should also have sufficient electrons to form covalent or coordinate bonds with metals, e.g.>N—M—N<, where M is a metal.
Generally the porphyrinogenic ring system contains four 5-membered heterocyclic rings. When the ketone is cyclohexanone, there will also be four 6-membered carbocyclic rings, comprising the linking groups.
The term “non-deleterious substituent” means a substituent which does not interfere with formation of the porphyrinogenic ring system or the subsequent reaction of the resin product with other materials, as described hereinafter.
In one preferred aspect of the invention the porphyrinogenic resin is obtained by the reaction of pyrrole, N-methylpyrrole, or a mixture of the two, with cyclohexanone in the presence of an acid catalyst.
The resin product may be modified by reaction with one or more acrylic monomers, for example butyl acrylate or acrylic acid. Alternatively, the pyrrole (or other reagent (a)) may be reacted with the modifier before or during reaction with reagent (b), to achieve the desired modification.
The resin products of the invention can be used alone as coating compositions or as part of a coating system. Advantageously, they may be combined with other materials for this purpose, including known coating materials or compositions, or precursors of such materials. Thus coating systems of many kinds can be advantageously formulated using the resin products of this invention. Such coating systems include, for example, combinations of the porphyrinogenic resins with epoxy, phenolic- or alkyd-based resins of known types.
Coatings or coating compositions in accordance with this invention find applications in a variety of fields, for example, they can be used in the paint industry generally and especially in anti-corrosion coatings for metals in the automotive, marine and general engineering industries. They can be utilised as decorative or protective coatings on various substrates, such as metals, paper and ceramics. They can be used as insulating coatings or as coatings for printing or masking substrates, e.g. in processes involving etching.
In particular, the resin products of the invention can be reacted with other unsaturated polymeric or polymerisable materials. Among the reagents which can be used for this purpose are polymerisable monomers, oligomers or other polymer precursors which possess appropriate reactive groups. Oligomer types which contain such groups include:
(i) melamine based oligomers
(ii) epoxy oligomers
(iii) polyurethane oligomers or
(iv) alkyd resin precursors.
Oligomers may be terminated (“end capped”) or reactive.
Preferred oligomer types are the alkyd resin precursors, such as acrylic-melamine, melamine-alkyd or simple alkyd formations.
Examples include castor oil base alkyds, soya bean oil alkyds, rosin esters, —OH rich esters and COOH rich esters (rosin precursors), —OH deficient and —COOH deficient resins.
Such reactions may require the presence of a catalyst. Inorganic acids, such as HCl or organic acids, especially acrylic acid, may be used as catalysts. Metal salts are also useful as catalysts, particularly salts of the Transition Metals (Groups 3 to 12 of the Periodic Table) and the heavier metals of Group 14. Apart from acting as catalysts, these metals can also form coordination complexes with porphyrinogenic moieties, giving rise to coloured products which are useful in coating formulations.
Conveniently, the metal halides may be used, examples of which are the chlorides of copper, iron(III), molybdenum, nickel, manganese, mercury and lead. The resin products of the invention have also been found to be capable of undergoing further reaction with metal surfaces and to thereby form strongly adherent coatings which are highly resistant to saline solutions and other corrosive materials.
The resin products of the invention (and their reaction products with other polymeric/polymerisable materials) are also capable of reaction with organic or inorganic pigments, transition metal oxides or transition metal complexes. The coloured coatings thus formed have excellent colour fastness and anticorrosive properties.
The pigment ferric oxide (Fe 2 O 3 ), which is present in some commercial coating formulations, can play an important role in the curing (crosslinking) of the coating systems of the invention. Other iron oxides (FeO, Fe 3 O 4 ) and the oxides of other transition metals are also useful in this regard.
Two processes involving Fe 2 O 3 are believed to occur during the curing process:
(i) Reaction between Fe 2 O 3 and the porphyrinogenic ring system to form a metal-porphyrinogenic complex; and
(ii) A role in the formation of crosslinks between the porphyrinogenic ring system and other polymerisable components in the coating system.
We have found that incorporation of a pigment into the formulation of a porphyrinogenic coating not only enables the coating to be used as a “one pot” (i.e. both top coating and primer) anticorrosion coating, but also significantly improves the anticorrosion properties of the coating.
Some specific, illustrative embodiments of the invention are described below.
A. Pyrrole and cyclohexanone are reacted together in the presence of a catalyst (preferably acetylene dicarboxylic acid). Butyl acrylate is added and the mixture allowed to further react, after which butanol is added to terminate the reaction.
B. Pyrrole and cyclohexanone are reacted together in the presence of a catalyst (preferably HCl and crotonaldehyde). Acrylic acid is added and the mixture allowed to further react. Tetrahydrofuran (THF) is added, to terminate the reaction.
C. Methyl pyrrole, cyclohexanone, and butyl acrylate are reacted in the presence of a catalyst (preferably HCl). Acrylic acid is added and the mixture allowed to further react. Butanol is added to terminate the reaction, followed by addition of THF.
In each of the above embodiments the resin thus obtained may then be converted to a coating formulation by reacting it with at least one other unsaturated resin, for example, in the presence of hydrochloric acid and a suitable aldehyde.
Coating system in accordance with this invention are usually in the form of liquids or semi-solids. They may also be produced in powdered form, for example, by grinding a partially polymerised solid formulation. In use, the temperature of the surface being coated is raised to give fusion of the powdered particles and subsequent rapid crosslinking/curing.
The invention is further described and illustrated by reference to the following non-limiting examples, which show the preparation of various porphyrinogenic resins and their formulation into coatings with other polymerisable resins or commercial coating formulations. The materials used are characterised as follows:
Resin 4835 is produced by UCB, Belgium, and is composed of an acrylated methane resin (90%) and tetraethylene glycol (10%).
Comma Stop Rust is produced by Comma, Gravesend, Kent, U.K. (Product Code GC311EH) and is composed of ferric oxide (Fe 2 O 3 ) in a conventional resin formulation.
Coatings were formulated by blending the components shown in the Table comprised in the Examples and were tested for corrosion resistance as follows:
Mild steel nails (100 mm length and 4.8 mm diameter) or mild steel wire pins (63.5 mm length and 1.6 mm diameter) were dip-coated with the formulation under test and air-dried for 5 days. The samples were suspended in salt solutions of varying pH, as set out in Table A and in xylene and butanol. Test were conducted at room temperature and in some cases at 125° C.
TABLE A
Composition of the Corrosion Test Solutions
Composition (grams/liter)
NaCl(s)*
36% HCl
98% H 2 SO 4
NaOH(s)
2.7% Saline, pH = 7
27
2.7% Saline, pH = 2
27
7
2.7
2.7% Saline, pH = 4
27
7
2.7
4
2.7% Saline, pH = 13
27
2
EXAMPLE 1
Porphyrinogenic resin (Resin A) and coating system (1)
(a) Resin
TABLE 1
Preparation of Porphyrin Resin A
Material
Composition (%)
Pyrrole
10
Cyclohexanone
36
ADCA
0.24
Butyl acrylate
36
Butanol
27.76
The procedure for producing Resin A is as follows.
Reactions were carried out at room temperature, i.e. 20-25° C., unless otherwise specified.
ADCA (acetylenedicarboxylic acid; the catalyst) was dissolved in cyclohexanone. Pyrrole was to the ADCA-cyclohexanone solution and the reaction allowed to proceed for 3 hours at room temperature (or 2 hours at 60°-65° C.). In practice, the end point of this reaction is indicated by the colour change of the reaction system from amber to orange.
Butyl acrylate was then added and the reaction system heated at 85°-90° C. for 2-3 hours. The end point of this reaction is determined by the increase of the viscosity of the reaction system to a desired value.
At this point, butanol is added which terminates the reaction by esterification of (blocking) the residual —COOH groups. The temperature of the reaction system then is brought up to between 110° and 115° C. and maintained in that range for a further hour to obtain the product (Resin A).
(b) Formulation.
The formulation is given in Table 2. Resin A is blended with the catalyst (HCl and crotonaldehyde), Resin 4835 and xylene to give the coating system.
TABLE 2
Formulation of Porphyrinogenic Coating System 1.
Substance
Composition (%)
Resin A
61.6
Catalyst
10
{5% HCl (36%), 95% Crotonaldehyde}
Resin 4853
23.4
Xylene
5
(c) Testing
Test results are set out in Table 3.
TABLE 3
Anticorrosive Properties of Porphyrin Coating System 1.
Corrosive Environment
Observation
At Room Temperature
(1) 2.7% Saline, pH 2
Neither rust on the metal surface nor
damage of the coating is observed after
146 days. Coating remains tough.
(2) 2.7% Saline, pH 4
Same as in (1).
(3) 2.7% Saline, pH 7
One rusty pin-hole was observed after 94
days which developed into a rusty area
about 1 mm in diameter after 145 days.
Coating remains tough.
(4) 2.7% Saline, pH 13
One pin-hole was observed after 101
days which developed into a rusty area
about 1 mm in diameter after 146 days.
Also coating became soft.
(5) Xylene
No damage on coating was observed
after 146 days. Coating remained tough.
(6) Butanol
No damage on coating is observed after
146 days but two pin holes were
observed.
At 125 ° C.
(7) 2.7% Saline, pH 7
No damage on the coating was observed
in the immersed part after 24 days. (*)
(*) Sample was discarded due to rust in the unimmersed part. This is probably due to the crystallised NaCl on the unimmersed coating surface while water evaporates from the corrosive solution at the elevated temperature.
EXAMPLE 2
Porphyrinogenic Coating System (2) based on Resin A
(a) Resin A (Example 1(a)) was used.
(b) Formulation
TABLE 4
Formulation of Porphyrin Coating System 2
Material
Composition (%)
Resin A
42
Resin 4835
54
Comma (Commercial grade)
42
Xylene
2
(c) Testing
Test results are set out in Table 5.
TABLE 5
Anticorrosive Properties of Porphyrinogenic Coating System 1.
Corrosive Environment
Observation
At Room Temperature
(1) 2.7% Saline, pH 2
Coating remains perfect after 60 days.
(2) 2.7% Saline, pH 4
Same as in (1).
(3) 2.7% Saline, pH 7
Same as in (1).
(4) 2.7% Saline, pH 13
Same as in (1).
(5) Xylene
Several pin-holes observed after 60 days.
(6) Butanol
Coating remains perfect after 60 days.
At 125° C.
(7) 2.7% Saline, pH 7
Coating remained perfect after 60 days.
(*)
(*) Sample was discarded due to rust in the unimmersed part. This is probably due to the crystallised NaCl on the unimmersed coating surface while water evaporates from the corrosive solution at the elevated temperature.
EXAMPLE 3
Porphyrinogenic resin (Resin B) and coating system (3)
(a) Resin
TABLE 6
Preparation of Porphyrinogenic resin (Resin B) Coating System 3.
Substance
Composition (%)
Pyrrole
7.4
Cyclohexanone
40.7
Acrylic Acid
17.2
Catalyst
1.3
{7.7% HCl (36%); 92.3% Crotonaldehyde}
THF
5.0
Xylene
28.4
Resin B was prepared as follows.
Cyclohexanone and the catalyst (crotonaldehyde and HCl) were thoroughly mixed. Pyrrole was added while stirring and the reaction allowed to proceed for 15 to 30 minutes. Acrylic acid was then added and the reaction allowed to proceed for 24 hours, after which THF was added and the reaction allowed to proceed for one hour. Finally xylene was added.
(c) Testing
Test results are set out in Table 7.
TABLE 7
Anticorrosive Properties of Porphyrinogenic Coating System 3.
Corrosive Environment
Observation
At Room Temperature
(1) 2.7% Saline, pH 2
Neither rust on the metal surface nor
damage of the coating was observed
after 92 days. Coating remained tough.
(2) 2.7% Saline, pH 4
Same as in (1).
(3) 2.7% Saline, pH 7
Same as in (1).
(4) 2.7% Saline, pH 13
Same as in (1).
(5) Xylene
Two pin-holes were observed after 92
days. Coating remained tough.
(6) Butanol
No damage to the coating was observed
after 92 days. Coating remains tough.
(7) Cyclohexanone
Coating cracked after five hours. All
coating fell off the metal surface after 24
hours.
At 125 ° C.
(8) 2.7% Saline, pH 7
Coating remained perfect after 61 days.
(*)
(*) Sample was discarded due to rust in the unimmersed part. This is probably due to the crystallised NaCl on the unimmersed coating surface while water evaporates from the corrosive solution at the elevated temperature.
EXAMPLE 4
Porphyrinogenic resin (Resin C) and coating systems (4 and 5)
(a) Resin
TABLE 8
Preparation of Porphyrinogenic Resin C
Material
Composition (%)
Methylpyrrole
4.5
Cyclohexanone
46.2
Butyl acrylate
4.5
HCl (36%)
0.4
Acrylic acid
6.6
Butanol
33.3
THF
4.5
Resin C was prepared as follows.
Cyclohexanone, butyl acrylate and the catalyst (HCl) were thoroughly mixed. Methylpyrrole was added while stirring and the reaction allowed to proceed for 15 to 30 minutes, during which methyl groups were effectively removed from the methylpyrrole. Acrylic acid was then added and the reaction allowed to proceed for 10 hours at room temperature (or at 50-60° C. for 2 hours). The temperature was then increased to 80° C. and the reaction proceed allowed to proceed for two hours at this temperature.
Butanol was then added, the temperature increased to 115° C. and the reaction allowed to proceed for a further hour. The reaction mixture was cooled to between 100° C. and 110° C. THF was added and the reaction allowed to proceed for one further hour.
(b) Formulation
Two typical coating systems made by blending Resin C with other resins and solvents, are described as follows.
(i) Coating System (4). Resin C was blended with an equal amount of Comma Stop Rust. The results of the anti-corrosion studies of this coating system are detailed in Table 9.
TABLE 9
Anticorrosive Properties of Porphyrinogenic Coating System 4.
Corrosive Condition
Observation
At Room Temperature
(1) 2.7% Saline, pH 2
Neither rust on the metal surface nor
damage of the coating was observed
after 110 days. Coating remained tough.
(2) 2.7% Saline, pH 4
Same as in (1).
(3) 2.7% Saline, pH 7
Same as in (1) but one pin-hole was
observed.
(4) 2.7% Saline, pH 13
Same as in (1).
(5) Xylene
No damage on coating was observed
after 110 days. Coating remained tough.
(6) Butanol
No damage to the coating was observed
after 110 days but a small number of
pin-holes were observed.
At 125° C.
(7) 2.7% Saline, pH 7
No rust of the metal surface was
observed after 37 days but a small
number of pin-holes on the coating were
observed. Experiment was terminated
after 40 days because unimmersed part
cracked.
(ii) Coating System (5)
Coating system (5) was obtained by blending 39% of Resin C with 49.7% of the commercial Comma Stop Rust and 11.3% of Resin 4853. Its anti-corrosion properties are shown in Table 10.
TABLE 10
Anticorrosive Properties of Porphyrinogenic Coating System 5.
Corrosive Condition
Observation
At Room Temperature
(1) 2.7% Saline, pH 2
Neither rust on the metal surface nor
damage of the coating was observed
after 112 days. Coating remained tough.
(2) 2.7% Saline, pH 4
Same as in (1).
(3) 2.7% Saline, pH 7
Same as in (1) but one pin-hole was
observed.
(4) 2.7% Saline, pH 13
Same as in (1).
(5) Xylene
No damage on coating was observed
after 112 days. Coating remained tough.
(6) Butanol
No damage to the coating was observed
after 112 days but a small number of
pin-holes were observed.
At 125° C.
(7) 2.7% Saline, pH 7
No damage to the coating surface was
observed other than one rusting pin-hole
after 42 days. Experiment was
terminated after 45 days because
unimmersed part cracked.
EXAMPLE 5
Porphyrinogenic resin (Resin D) and coating system (6)
This example illustrates resin formation wherein acrylic acid functions as both a catalyst (for the formation of the porphyrinogenic resin) and a reactant for modifying the resin product.
(a) Resin
TABLE 9
Preparation of Porphyrinogenic Resin D
Material
Composition (%)
Cyclohexanone
36.72
Acrylic acid
20.00
Crotonaldehyde
1.00
HCl (36%)
0.03
Pyrrole
7.91
Butanol
19.40
THF
2.99
Butyl acetate
11.95
Resin D was prepared as follows.
The cyclohexanone, acrylic acid, crotonaldehye and HCl were thoroughly mixed. Pyrrole was added while stirring and the reaction allowed to proceed for 4 to 5 hours at room temperature. The temperature was then increased to 65±2° C. and the reaction proceed allowed to proceed for a further 1-2 hours at this temperature.
Butanol was then added (to block the COOH groups of the acrylic acid), the temperature was increased to 75±2° C. and the reaction was allowed to proceed for a further 1-2 hours. THF was added dropwise (to remove residual HCl) and the reaction allowed to proceed for one further hour at 65-70° C.
The reaction system was allowed to cool to below 50° C., the butyl acetate (which serves as a solvent) was added with stirring and the mixture thoroughly stirred.
(b) Formulation
Coating System (6). Resin D (43.64%) was blended with Resin 4835 (14.55%), Comma Stop Rust (27.27%) and butyl acetate (14.54%). The results of the anti-corrosion studies of this coating system are detailed in Table 10.
TABLE 10
Anticorrosive Properties of Porphyrinogenic Coating System 6.
Corrosive Condition
Observation
At Room Temperature
(1) 2.7% Saline, pH 2
Neither rust on the metal surface nor
damage of the coating was observed
after 114 days. Coating remained tough.
(2) 2.7% Saline, pH 4
Same as in (1).
(3) 2.7% Saline, pH 7
Same as in (1).
(4) 2.7% Saline, pH 13
Same as in (1).
(5) Xylene
Two pin-holes were observed after 114
days. Coating remained tough.
(6) Butanol
No damage to the coating was observed
after 114 days; Coating remained tough.
(7) Cyclohexanone
Coating cracked after 5 hours. All
coating fell off the metal surface after 24
hours.
At 125° C.
(S) 2.7% Saline, pH 7
Coating remained perfect after 64 days.
(Sample was discarded because coating
cracked due baking.)
EXAMPLE 6
Coating System (7)
This example demonstrates an anticorrosion coating formulation using iron oxide, silicon dioxide and zinc oxide as the pigment system. This is an alternative to the system described in Example 5, which uses the commercial product “Comma Stop Rust”.
(a) Formulation
The formulation of an anticorrosion coating system, based on porphyrinogenic resin (Y) and an iron oxide/silicon dioxide/zinc oxide pigmentation system (X), is given in Table 11.
TABLE 11
Formulation of Pigmented Porphyrinogenic Coating System
Materials
Composition (%)
Iron Oxide
12.14
Silicon Dioxide
1.70
Zinc Oxide
1.94
Resin 4835
16.72
Resin AT-410*
10.50
Butanol
14.50
Tetramethylsilane
0.50
Porphyrinogenic Resin (D)**
42.00
*an acrylic resin made by Rohm and Haas Company, Philadelphia, PA, USA
**from Example 5
Zinc oxide is a non-toxic, white pigment which has good anticorrosion properties, good light fastness, good resistance to temperature extremes and good weatherability. Because of its slight basicity zinc oxide can react with the residual carboxyl acids in resins to form carboxylic group/zinc complexes. This reaction increases the viscosity of the coating system and consequently inhibits the flocculation of pigments during storage of coloured coatings.
Silicon dioxide is well known in the art and used as a viscosity modifying, and strength enhancing filler in coating formulations. Silicon dioxide also gives a significant shear-thickening tendency to the total resin system. While this property helps prevent the silicon dioxide from flocculating during storage of the compositions, it may give rise to difficulties in the milling operation.
Tetramethylsilane (TMS) is included to prevent pigment floating. As such, it is widely used in the coatings industry. During curing processes, pigments tend to migrate to the surface of the coating thus giving rise to colour separation on the coating surface, when cured. Iron oxide, being low in its specific weight, has a tendency to migrate towards the coating surface. Tetramethylsilane and related compounds, when included in a coating formulation, can form a uniform thin film on the coating surface which reduces the rate of solvent evaporation from the coating system and also reduces the surface tension of pigment. Thus, the uniformity of components in the coating system can be maintained at the desired level during the process of cure and consequently, colour separation phenomena can be minimised.
Each of the above components (zinc oxide, silicon dioxide and TMS) can be replaced by other materials having similar functions and known per se in the art.
(b) Preparation
As can be seen from Table 11, the anticorrosion coating system is composed of 58% of mixture X and 42% of porphyrinogenic resin (Y). The system was prepared as follows:
15 g of Resin 4835 (UCB) was mixed with 50 g of butanol in a ball-milling container with stirring to achieve a uniform mixture. 50 g of iron oxide, 7 g of silicon dioxide and 8 g zinc oxide were added to the mixture. Again, stirring was needed to help the dispersion of these pigments/fillers in the mixture.
Ball-milling spheres are put into the ball-milling container and the mixture was milled until the particle size of the pigments/fillers fell below 20 μm. 55 g of Resin 4835, 45 g of Resin 410A and tetramethylsilane were then mixed in to give the iron-oxide based anticorrosion resin (X). Mixing was terminated when a uniform distribution of all the components had been achieved.
Resin X was then mixed with the porphyrinogenic resin (Y) in the ratio 58:42 to give the final anticorrosion coating.
(c) Coating Properties
(i) Non-volatile Solids
Non-volatile solids content provides one of the quality control parameters in coating manufacture. It is defined as the ratio of the weight (W 2 ) of the non-volatile solids to the weight of total coating sample (W 1 ). The weight of non-volatile solids is that of the coating sample measured after the coating has been heated at 120° C. is an oven for 3 hours. The non-volatile solids value is expressed percentage terms, i.e. W 2 ×100/W 1 (%).
(ii) Particle Size (or Pigment Dispersion)
The particle size of pigments in coating is one of the important parameters in quality control. From a physical point of view, the size of the pigment particles in the individual coating system has great effects on the uniformity of pigment distribution in the coating, on the gloss of coating surface, on the anticorrosion properties and on the stability during storage. For approximate assessments of particle size in “real coatings”, a grind gauge is usually used. The readings have units of μm.
(ii) Levelling time
The levelling time of coating is a measure of the time taken to achieve levelness in the coating after it has been applied to a smooth surface either by brushing or by spraying. The usual approach to measuring the coating leveling time is as follows:
(1) Apply the first coating layer onto object surface with a paint brush.
(2) Apply, with a paint brush, the second coating layer, on top of the first coating layer, when the first coating layer is surface-dry. With paint brush, immediately stroke across the second layer in the direction perpendicular to the normal brushing direction.
(3) The time for the bush marks to disappear, i.e. for the paint surface to level up to a smooth surface, is recorded.
The leveling time of coating is usually defined as grades. A satisfactory leveling time concerns a paint with a leveling time of less than 10 minutes. An acceptable leveling time concerns to paint with leveling time between 10 and 15 minutes. Unacceptable leveling times concerns to paint with leveling time longer than 15 minutes.
(iv) Dry Hiding Power
The approach to measurements of the dry hiding power of X-Y prophyrinogenic coating employed in our laboratory is as follows:
(1) Introduce a specific, known amount of the X-Y porphyrinogenic coating system into a 10 cm 3 glass sample bottle.
(2) Coat, uniformly, a glass plate with black and white square area, using X-Y porphyrinogenic coating from the sample bottle. The coating is applied as thinly as possible while ensuring that no white areas are visible.
(3) Weigh the bottle with remaining X-Y porphyrinogenic coating to obtain the amount of coating sample used.
The dry hiding power, P DH is calculated by P DH = G ( gram ) A ( m 2 )
where, P DH denotes dry hiding power of the coating sample, G refers to weight of coating sample used and A is the total area of glass plate.
(v) Curing Time
Curing of the coating can be classified into three stages. These are surface cure, through cure and full cure. In most coating application processes, it is desirable that the surface cure and the through cure should take short time while full cure takes relatively long time. This is because rapid surface cure and through cure ensure the existing of a rapid coating application process and the slower full cure gives a highly ordered crosslinking and complexing which consequently ensures the development of good coating properties.
The times for surface cure and through cure of X-Y porphyrinogenic coating were measured. The measuring methods are as follows. (The full cure time was not measured.)
Surface-cure Time
A dry cotton ball of about 5 mm diameter is placed on the surface of the coating panel. The coating panel is placed about 10-15 cm from an air jet. Slight blowing is then applied on the cotton ball. Surface cure is considered to be achieved when the cotton ball can be blown off the coating surface and no cotton fibre sticks to the coating surface. The surface cure time is the time which elapses between the end of the coating application and the time when surface cure is confirmed.
Through Curing Time
A 20×20 mm 2 quantity filter paper is placed on the surface of coated panel. A 200 g weight with circular bottom (1.13 cm in diameter) is then placed on top of the filter paper. After 30 seconds, the weight is removed and the coating panel turned upside down. Through cure is considered to have been realised if the filter paper falls of the coated surface and no fibre sticks to the coated surface. The time which elapses between the end of coating application and the time when through cure is achieved is the through cure time.
(d) Results
The basic coating properties of the X-Y porphyrinogenic coating derived from our measurements, are given as Table 12.
For comparison, the properties of the porphyrinogenic coating based on the previous formulation (Example 5) involving Comma Stop Rust as are given as Table 13.
TABLE 12
Properties of the X-Y Porphyrinogenic Coating System
Property
Value
Non-volatile Solids
53.19%
Dispersion
<20 μm
Surface Curing Time
Room Temperature 15 mins
120° C. 5 mins
Through Curing Time
Room Temperature 3.0 hours
120° C. 0.5 hours
Leveling Time
10-15 mins
Dry Hiding Power
58 g/m 2
TABLE 13
Properties of Example 5 Formulation
(involving Comma Stop Rust)
Property
Value
Non-volatile Solids
53.05
Dispersion
<20 μm
Surface Curing Time
Room Temperature 20 mins
120° C. 10 mins
Through Curing Time
Room Temperature 4.5 hours
120° C. 1.0 hours
Leveling Time
10 mins
Dry Hiding Power
60 g/m 2
The anticorrosion properties of the X-Y system are shown in Table 14.
TABLE 14
Anticorrosive Properties of Porphyrinogenic Coating System (7)
Corrosive Condition
Observation
At Room Temperature
(1) 2.7% Saline, pH 2
Coating remains hard after 150 days
(2) 2.7% Saline, pH 4
Rusty areas observed after 124 days
(3) 2.7% Saline, pH 7
Rusty areas observed after 120 days
(4) 2.7% Saline, pH 13
Rusty areas observed after 24 days
(5) Xylene
Coating fell off after 70 days
(6) Butanol
Coating fell off after 65 days
At 125° C.
(7) 2.7% Saline, pH 7
Rusty areas observed after 20 days
EXAMPLE 7
Coating System (8)
This example demonstrates another anticorrosion coating formulation using iron oxide. This is an alternative to the system described in Example 6, in which the UCB Resin 4835 and Rohm & Hass Resin AT-410 are replaced by other commercial resins which show improved compatibility with the porphyrinogenic resin.
(a) Formulation
The system was formulated from the materials listed in Table 15.
TABLE 15
Formulation of Pigmented Porphyrinogenic Coating System
Materials
Composition (%)
Iron Oxide
10.50
NaBO 4
2.31
Heucophos ZPZ 1
2.10
Pole Star 200P Al—Si 2
1.68
Butanol
4.00
UCB Ebecryl 600 3
12.15
Synolac 9110 4
23.00
Dow Corning Silicate Additive 29 5
1.26
BYK Additive 307 6
1.00
Porphyrinogenic Resin (D)**
42.00
1 Heucophos ZPZ is a modified phosphate hydrate-based wetting agent manufactured by Heuback GmBH and Co., Germany.
2 Pole Star 200P Al—Si is a mixture containing Al 2 O 3 and SiO 2 supplied by Kalon Group plc, UK.
3 UCB Ebecryl 600 is an epoxy acrylate resin manufactured by UCB, Belgium.
4 Synolac 9110 is an alkyd resin manufactured by Toval (Cray Valley Products Ltd, UK).
5 Dow Corning Silicate Additive 29 contains the C—OH functional group. It is an additive designed to assist in leveling and flow-out. It also has anti-floating properties.
6 BYK Additive 307 is a polyether-modified dimethyl polysioxane copolymeric assembly designed to increase surface slip, substrate wetting and leveling.
**from Example 5
The iron oxide, NaBO4, (anticorrosion agent) Heucophos ZPZ, Pole Star 200P Al—Si, butanol and half of the specified amount of UCB Ebecryl 600 were placed in a ball milling jar. The mixture was ball milled until the particle size was less than 20 μm.
The milled ingredients were then blended with the balance of the Ebecryl 600 and the Synolac 9110, Dow Corning Silicate Additive 29 and BYK Additive 307 (the last two being added as a 1% solution in butanol) to give a pigmented resin.
58% by weight of this mixture was blended with 42% of porphyrinogenic resin (D), to produce a ready-to-apply resin coating system.
(b) Coating Curing Properties
The ready-to-apply coating system, prepared as above, has the curing rates detailed in Table 16.
TABLE 16
Pigmented Coating Curing Properties
Curing Temperature
Curing Status
Curing time
Room Temperature (20° C.)
Surface Cure
30 minutes
Through Cure
300 minutes (5 hours)
120° C.
Surface Cure
10 minutes
Through Cure
60 minutes (1 hour)
260° C.
Surface Cure
15 seconds
(c) Anticorrosion Properties of Coatings
The pigmented porphyrinogenic coating prepared according to the formulation as given in Table 15 has superior gloss. This gloss is maintained for more than 48 hours at 120° C. The ready-to-apply coating system, (i.e. the mixture of the pigmented resin and the porphyrinogenic resin) is stable for at least seven days at room temperature. The results of anticorrosion studies are described in Table 17.
TABLE 17
Corrosion
Corrosion
Environment
Temperature
Observation
Remarks
5% Saline, pH 2
Room
Coating remains hard
Saline
5% Saline, pH 4
Temperature
and glossy after 65 days
Resistance
5% Saline, pH 7
(20° C.)
5% Saline, pH 13
5% Saline, pH 7
120° C.
One rusty pin-hole after
61 days.
Several rusty areas
appear after 65 days
Fridge
−20° C.
Coating remains hard
Weathering
Roof
and glossy after 65 days
Effect
Xylene
Room
Coating becomes soft
Solvent
Butanol
Temperature
Coating becomes soft
Resistance
and solvent becomes
light-red
EXAMPLE 8
Coating System (9)
This example shows the preparation of a powdered porphyrinogenic resin coating system.
TABLE 18
Preparation of a Powdered Porphyrinogenic Resin
Material
Composition (%)
Pyrrole
7.6
Cyclohexanone
22.0
Crotonaldehyde
1.7
Acrylic acid
11.7
Fe 2 O 3
14.8
NaBO 4
3.2
GY260 1
33.7
Heucophas ZPZ
2.9
Pole Star 200P Al—Si
2.4
1 GY260 is an epoxy resin manufactured by Ciba-Geigy AG
The resin was prepared as follows:
The pyrrole, cyclohexanone, crotonaldehyde and acrylic acid were mixed and gently and continuously stirred for 15 hours at room temperature. The GY260 resin was added and the mixture stirred for a further hour at 120° C.
The remaining materials were added and the mixture stirred for a further 10 minutes at 120-130° C.
Because of the presence of the epoxy resin component (GY260) the resulting solid product is only partially cured or is capable of delayed cure. The solid product is ground to produce the powdered resin product. | Polymerisable resins which comprise a porphyrinogenic ring system obtained by the reaction of:
(a) one or more compounds selected from the group consisting of pyrrole and N-(lower)alkyl pyrroles, any of which may be optionally substituted, and
(b) a C 4 -C 6 saturated alicyclic ketone which is capable of reacting with the 2 or 5 position of the pyrrole ring.
Resin coating systems comprising the said resins. | 2 |
FIELD OF THE INVENTION
The present invention relates to a method for traffic control in a communication system transferring traffic units, the method comprising the steps of maintaining a continuously changing quantity for the traffic units, the value of the quantity at any one time determining whether an individual traffic unit can be accepted to be forwarded; changing, at accepted traffic units, the value of said quantity so that a traffic density lower than a specific predetermined value changes the value of the quantity in a first direction but no more than up to a predetermined first limit, and a traffic density higher than said predetermined value changes the value in a second direction; and beginning rejection of traffic units as the value of the quantity in said second direction reaches a specific predetermined second limit. The invention further relates to traffic filters for limiting traffic in a communication system forwarding traffic units, such as cells.
The solution according to the invention may be utilized for example in measuring cell traffic in an ATM network, but it is applicable in connection with other kind of traffic as well, for example in call transfer, as will be disclosed below. Due to the many operational environments, the cells, packets, calls etc entities transferred in the system will below be referred to with a general term “traffic unit”.
BACKGROUND OF THE INVENTION
Usually, at the connection establishment or at the connection set-up phase, the parameters to be complied are agreed upon. Typical connection parameters include traffic maximum rate and average rate. From the point of view of the network, it is not certain that the parameters agreed upon would automatically be complied on each connection. A reason for this is that it is difficult for a user to know accurately the nature of the traffic in advance. E.g., the average bit rate of a compressed video signal may be very difficult to determine in advance. The subscriber equipment may also be faulty or the users may, quite on purpose, to underestimate their bandwidth requirements to keep the costs lower. Due to e.g. the above reasons, it must be ensured at the network-subscriber interface that the traffic sources stay within the limits agreed upon at the connection set-up phase.
Various kinds of mechanisms have been developed for traffic source policing, most of which police the average and maximum rates of the traffic source and the duration of active periods. One of such mechanisms is a so-called “leaky bucket” principle. The principle of leaky bucket is disclosed e.g. in the reference Raif O. Onvural: Asynchronous Transfer Mode Networks, Performance Issues, Arctech House Inc., 1994 (ISBN 0-89006-662-0), Chapter 4.5.1. The leaky bucket principle is used e.g. by the GCRA algorithm (Generic Cell Rate Algorithm) of an ATM (Asynchronous Transfer Mode) network UPC (Usage Parameter Control) function, the GCRA being used to police that cell traffic is in accordance with the traffic agreement of the connection in question.
The aforementioned prior art mechanisms are not, however, the best possible e.g. in such applications in which a specific (smaller) information unit, such as a cell, is critical from the point of view of correctly receiving a larger information unit. In such a case, losing a smaller information unit e.g. an AAL (=ATM Adaptation Layer) frame might lead to having to retransmit a larger amount of information. To take an example, if the data stream has been divided into “segments” that are compressed and encrypted so that each encrypted data unit is hundreds of cells long, the loss of one or more cells may lead to the receiver being incapable of reconstructing the data unit, and all the cells of the unit in question have to be retransmitted.
Utilizing prior art policing mechanisms in connection with embodiments of the type described above results in wasting the network resources. This is because the known mechanisms limit traffic so that the accepted traffic is always in accordance with the traffic agreement (i.e. only traffic units violating the traffic agreement are rejected), whereby rejecting a specific portion easily results in that also previously accepted traffic units have to be retransmitted.
BRIEF DESCRIPTION OF THE INVENTION
It is an object of the present invention to provide, in as simple as possible a manner, an improvement on the drawback set forth in the above. This object is achieved by the method according to the invention, which is characterized in that the value of the quantity is also changed at rejected traffic units in said second direction, but no more than up to a specific predetermined third limit, and that when the value of the quantity is between the second and the third limit, it must again alter in said first direction up to at least said second limit before traffic units are accepted. The second embodiment of the invention relates to a method for traffic control in a communication system forwarding traffic units, the method comprising the steps of calculating a Theoretical Arrival Time (TAT) for the next traffic unit to arrive, whereby the actual arrival time of the incoming traffic unit determines whether an individual traffic unit can be forwarded; changing, by means of accepted traffic units, the theoretical arrival time so that a traffic density lower than a specific predetermined value changes the theoretical arrival time less than a traffic density higher than said predetermined value; and rejecting a traffic unit arriving before the TAT to the extent of a specific predetermined instant of time (TAT-L). This invention is characterized in that also rejected traffic units are utilized in changing the theoretical arrival time, but no more than up to a specific predetermined limit (time+H).
The invention also relates to a filter for limiting traffic in a communication system forwarding traffic units, such as cells, the filter comprising means for maintaining the continuously changing quantity whose value at any one time determines whether an individual traffic unit can be accepted to be forwarded; means for changing the value of said quantity at accepted traffic units so that a traffic density lower than a specific predetermined value changes the value of the quantity in a first direction but no more than up to a predetermined first limit, and a traffic density higher than said predetermined value changes the value in a second direction; and means for rejecting traffic units as the value of the quantity reaches and exceeds in said second direction a specific predetermined second limit. The invention is characterized in that it further comprises means for changing the value of the quantity at rejected traffic units in said second direction but no more than up to a specific predetermined third limit.
The invention further relates to a filter for limiting traffic in a communication system forwarding traffic units, such as cells, the filter comprising calculating means for calculating the theoretical arrival time for the next traffic unit to arrive; comparing means for comparing the actual arrival time of the arriving traffic unit to the calculated theoretical arrival time and the time dependent thereupon; and decision-making means responsive to the comparing means for determining whether an individual traffic unit can be accepted to be forwarded. The invention is characterized in that the calculating means are adapted to change the theoretical arrival time also at rejected traffic units but no more than up to a specific predetermined limit.
BRIEF DESCRIPTION OF THE DRAWINGS
The idea of the invention is to modify the prior art policing mechanisms into low-pass direction so that they are able to filter all traffic from a traffic source not complying with the parameters agreed.
The solution according to the invention provides, in a simple manner, a policing mechanism by means of which it is possible to save network bandwidth in connection with the types of traffic sources described above.
In the following, the invention and its preferred embodiments will be described in greater detail with reference to the examples in the accompanying drawings, in which
FIG. 1 illustrates the prior art Token Bank principle,
FIG. 2 is a flow chart illustration of the operation of a gapping gate (i.e. filter) according to FIG. 1,
FIG. 3 a is a flow chart illustrating the method of the invention in its first embodiment,
FIG. 3 b is a block diagram illustration of a gapping gate operating as illustrated in FIG. 3 a,
FIG. 3 c illustrates the operation of the gapping gate according to the invention,
FIG. 4 is a flow chart illustrating the operation of a second prior art gapping gate,
FIG. 5 is a flow chart illustrating the method of the invention as applied to the prior art gapping gate of FIG. 4,
FIG. 6 is a flow chart illustrating the operation of a third prior art gapping gate,
FIG. 7 a shows a flow chart illustrating the method of the invention as applied to a gapping gate operating according to FIG. 6,
FIG. 7 b is a block diagram illustration of a gapping gate operating as in FIG. 7 a, and
FIG. 8 illustrates an alternative way of implementing the gapping gate according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
As the present invention only requires minor modifications to prior art policing mechanisms, the prior art Token Bank principle will first be briefly discussed with reference to FIGS. 1 and 2.
For incoming traffic units, such as cells, there is arranged a bank or pool of tokens 12 , to which tokens are added at a specific constant rate. The pool has a maximum size, and the tokens arriving in the pools when it is full will be wasted. Every arriving traffic unit must take a token from the pool before a server 11 forwarding traffic may forward it. If the pool is empty upon arrival of the traffic unit, the traffic unit in question will be rejected. The pool size determines the maximum limit for the burst size that can be forwarded. The pool of tokens is therefore in a way a resource which is created for the traffic stream, and which is reduced by the incoming traffic and increased, in turn, by time. The device could therefore be represented by a filter or a gapping gate G, the gate having one input denoted by the reference mark IN, and two outputs denoted by the reference marks PASS and GAP. The incoming traffic units are directed to the gapping gate input IN and the passed traffic units are forwarded from the output PASS. The gapping gate limits the frequency (frequency of occurrence) of the traffic units so that the amount of passed traffic within a time unit does not exceed the aforementioned gapping parameter U (traffic units per second). In case the amount of incoming traffic within a time unit exceeds the value U, the gapping gate directs some of the traffic units to the output GAP so that the rate of the output traffic from the port PASS is not higher than U.
FIG. 2 shows a flow chart of how a gapping gate based on the Token Bank principle operates. The following parameters are stored in the memory of the gapping gate:
time t 2 corresponding to the latest traffic unit arrived (which is initially the same as the current time t 1 ),
the gate limit value U (fixed value). In case the amount of average incoming traffic is lower than U, no gapping takes place (in an ideal case). In case the amount of traffic offered exceeds the value in question, the policing mechanism rejects part of the traffic units.
pool size B (fixed value), and
the pool counter value b, representing the number of “tokens” in the pool at any one time. Initially, the value of b may be e.g. zero, and the number of “tokens” may increase at a constant rate corresponding to the value limit U (as is apparent from the flow chart step 23 ). However, the pool size (the value of the counter) is only updated upon arrival of a traffic unit, and on the basis of the size a decision is made whether the traffic unit in question can be accepted.
Upon receiving a new traffic unit (step 21 ), the gapping gate stores the current time in a variable t 1 (step 22 ). Following this, the gapping gate updates the pool size i.e. calculates a value for the quantity [Ux(t 1 −t 2 )+b], compares it to value B and selects, for the variable b, the lower of these values. In addition, the gapping gate updates the value of the variable t 2 (step 23 ). Then, the gapping gate examines whether the variable b has a value higher than zero (step 24 ). If that is the case, the variable pass will be given the value true (T) and the counter will be decremented (step 25 a ). In case the counter value b is not higher than zero, the variable pass will be given the value false (F) (step 25 b ). Finally (step 26 ), the value of the variable pass will be returned, which means that the gate makes either a pass or a gap decision (the former if pass=T, and the latter if pass=F).
According to the invention, the operation of the policing method described above is modified so that traffic may accumulate not only “allowances” of tokens but also debt which it has to pay off before traffic may be forwarded. In practise, then, this means that the number of tokens may also be negative, i.e. the size of the pool not only has a positive limit (B) but a negative limit as well, denoted by the reference mark −D. This limit is hence the minimum value of the pool counter.
FIG. 3 a illustrates the operation of the gapping gate according to the invention. Upon arrival of a new traffic unit (step 31 ), the gapping gate stores the current time in the variable t 1 (step 32 ). Following this, the gapping gate calculates a value for the quantity [Ux (t 1 −t 2 )+b], compares it to the value B and selects, for the variable b, the lower of these values. In addition, the gapping gate updates the variable t 2 value (step 33 ). Then, the gapping gate examines whether the variable b (i.e. the pool size) has a value higher than zero (step 34 ). If that is the case, the variable pass will be given the value true (T) and the pool counter will be decremented (step 35 b ). In case the counter value b is not higher than zero, the variable pass will be given the value false (F) (step 35 a ). After this it is examined whether the counter value b is higher than the aforementioned predetermined minimum limit −D (step 36 ). If that is the case, the counter will be selected the higher of the values −D and b-1 (step 37 ). Then, the value of the variable pass will be returned at step 38 . If it is detected at step 36 that the counter value does not exceed −D, the process proceeds directly to step 38 , which is also reached directly from step 35 b at which the variable pass obtained the value true (T).
Thus, the counter will, according to the invention, be decremented per each rejected traffic unit until the lower limit −D is reached (cf. step 37 ). In other words, by means of the rejected traffic units, the counter is updated even after the pool is empty, whereby the traffic stream runs into “debt”. The traffic stream is in the “debt range” whenever −D≦b<0 holds true for the value b of the counter. As also shown by FIG. 3 a, the counter must indicate a value higher than zero in order for traffic units to be forwarded. A traffic stream with a rate much higher than the generation rate (U) of tokens is in constant “debt”, which means that all or at least the majority of traffic units will be rejected. In other words, the gapping gate operates in a low-pass fashion.
FIG. 3 b is a block diagram illustration of a gapping gate which may operate e.g. as that of FIG. 3 a. The core of the gapping gate is comprised of a decision-making unit DM which includes an input IN and outputs PASS and GAP (cf. FIG. 4 ).
The gapping gate further comprises a memory M 1 for the variables (t 1 , t 2 and b) as well as a memory M 2 for the constant parameters (U, B and −D). In addition to the memories, the gapping gate further comprises a calculating means CALC, a clock CLK and possibly a timing means T, which add “tokens” to the bucket (the timing means is not required, as is apparent from FIG. 3 a ). Upon arrival of a new traffic unit, the decision-making unit DM controls the clock CLK to store the current time in the memory M 1 , after which it controls the calculating means CALC to calculate the variable b value and to store it in the memory M 1 . Comparing the variable b then takes place within the decision-making unit. Depending on whether the variable b is higher than zero or higher than −D, the decision-making unit updates the correct variables as described above. Subsequently, the decision-making unit supplies a pulse either to the output PASS or the output GAP, depending on whether the traffic unit was passed or not.
The operation of the call gapping method is illustrated by FIG. 3 c. When the amount of average incoming traffic (depicted on the horizontal axis) is lower than the aforementioned maxim U, no gapping takes place (in an ideal case). When the average amount of the traffic offered exceeds the value in question, the gapping gate will reject all the traffic units (by directing them to the output GAP). The ideal case is represented by a broken line and a practical case by a solid line. In practise, the characteristic curve (solid line) representing the operation of the gapping gate is a smoothed approximation of the piecewise-linear characteristic curve (broken line) of the ideal case. The shape which the characteristic curve of the gapping gate will have also depends on the values given for the constant parameters D and B.
The leaky bucket or Token Bank principle can be illustrated in various ways depending on which variables are examined and which standpoint is chosen for examination. For example, it is not necessary to employ tokens but the resource employed may be time. Therefore, the following will describe the changes that the solution according to the invention will bring about in other similar prior art policing mechanisms.
FIG. 4 shows a flow chart of the continuous state leaky bucket mechanism which corresponds to the mechanism described in the ATM Forum's ATM User-Network Interface Specification, Version 3.1, p. 79). In this case, the gapping gate stores the following parameters in its memory:
the arrival time t 2 of the latest accepted traffic unit (initially the same as the current time t 1 ),
IAT (Inter Arrival Time), which is the inverse value of the gapping gate limit value U and the (fixed) increment unit by which the counter is incremented at each accepted traffic unit,
the counter value b, which increases as the traffic rate increases. The counter is decremented at a rate corresponding to the limit value U, but the decrementing is only realized upon arrival of a traffic unit,
a, which is an auxiliary variable corresponding in principle to the counter value b,
rejection limit L, corresponding to the counter value whose exceeding leads to rejection of traffic units. (The maximum value of the counter is L+IAT, and its minimum value, except for the short zeroing stage, is IAT.)
Upon arrival of a new traffic unit (step 41 ), the gapping gate stores the current time in the variable t 1 (step 42 ). Following this, the gapping gate gives the auxiliary variable the value a=b−(t 1 −t 2 ), i.e. the value which is obtained when the time that has lapsed from the latest passed traffic unit is subtracted from the current value of the counter (step 43 ). Then, the gapping gate examines whether the auxiliary variable b has a value lower than zero (step 44 ). If that is the case (i.e. only little traffic is present), the auxiliary variable will be set to zero (step 45 b ), after which the process proceeds to step 46 b where the counter is given the value b=a+IAT, the variable pass is given the value true (T) and the arrival time of the preceding accepted traffic unit is updated. (After step 45 b, the counter thus obtains the value IAT.)
If it is detected at step 44 that the auxiliary variable does not have a value lower than zero, it will be examined at step 45 a whether the auxiliary variable has a value higher than a specific upper limit L (i.e. whether the “bucket” after all contains accumulated “allowance” to the extent that it can be used to forward the traffic unit in question). If the value of the auxiliary variable exceeds L, the interval has been too short (too high a frequency of occurrence) in relation to the accumulated “allowance”, whereby the value false (F) is given to the variable pass at step 46 a, from which the process proceeds to step 47 where the value of the variable pass will be returned.
If it is detected at step 45 a that the value of the auxiliary variable a does not exceed L (i.e. the interval was not too short in relation to the accumulated “allowance”), the process proceeds to step 46 b where the value of the counter and the arrival time of the preceding accepted traffic unit are updated, and the value true (T) is given to the variable pass.
In this embodiment, the contents of the bucket (the contents corresponding to the counter value b) leaks out at a constant rate U, and on the other hand the contents of the bucket are incremented at every accepted traffic unit. The counter should always indicate a value lower than or equal to L in order for traffic units to be accepted.
In the solution according to the invention, the embodiment described above is modified as shown by FIG. 5, i.e. by adding a step after step 46 a (step 56 a in FIG. 5 ). In addition, the variable t 2 in this case denotes the time of arrival of the preceding traffic unit. The operation is as follows, the reference numbers corresponding to the example of FIG. 4 except that they begin with the number five according to the number of the Figure. The auxiliary variable a is not required here at all.
Upon arrival of a new traffic unit (step 51 ), the gapping gate stores the current time in the variable t 1 (step 52 ). Following this, the gapping gate updates the counter to the value b=b−(t 1 −t 2 ), i.e. the value which is obtained when the time that has lapsed from the preceding traffic unit is subtracted from the current value of the counter. In addition, the variable t 2 is given the value t 1 (step 53 ). Then, the gapping gate examines whether the auxiliary variable b has a value lower than zero (step 54 ). If that is the case, the counter will be set to zero (step 55 b ), after which the process proceeds to step 56 b where the counter is given the value b=b+IAT, and the variable pass is given the value true (T).
If it is detected at step 54 that the counter does not have a value lower than zero, it is examined at step 55 a whether the counter has a value higher than a specific upper limit L. If the counter value is higher than L, the variable pass is given the value false (F) at step 56 a. Following this, the process proceeds to step 57 where the value b+IAT is calculated, and the counter value is updated with the lower of b+IAT and H, where H is a predetermined counter upper limit which the counter is not allowed to exceed (note that 0<L<H). After the counter has been updated, the process proceeds further to step 58 where the value of the variable pass is returned.
If it is detected at step 55 a that the value of the counter does not exceed L, the process proceeds to step 56 b where the value of the counter and the arrival time of the preceding accepted traffic unit are updated as described above, and the value true (T) is given to the variable pass.
In this embodiment, too, updating the counter value per each rejected traffic unit is continued. In this case, the updating may only continue until reaching the counter upper limit H. Thus, the counter is updated even by rejected traffic units, whereby the traffic stream runs into “debt”. The “debt range” is this case refers to the range where L<b≦H holds true for the counter reading b. As indicated by FIG. 5, the counter reading must drop back to at least the limit value L before traffic units may be forwarded.
The operation illustrated in FIG. 5 may also be implemented by an apparatus such as illustrated in FIG. 3 b. In such as case, however, memory M 2 stores different (constant) parameters (U, L and H).
In the above, a modification was made to the known algorithm which was illustrated in FIG. 4 and described in the aforementioned ATM Forum UNI (User Network Interface) specification. A similar modification may be incorporated in the Virtual Scheduling algorithm, described in the aforementioned specification as being equivalent to the continuous state leaky bucket mechanism set forth above. FIG. 6 is a flow chart illustration of the Virtual Scheduling mechanism which handles running clock time. In this case, the gapping gate stores the following parameters in its memory:
TAT (Theoretical Arrival Time) is the theoretical arrival time which is compared to the current time. Thus, TAT corresponds to the time when the next traffic is due if the intervals between traffic units (of traffic steam at rate U) were equal.
IAT (Inter Arrival Time), which represents the inverse value of the gapping gate limit value U and the incrementing unit by which the counter is incremented at every accepted traffic unit, and
rejection limit L.
Upon arrival of a new traffic unit (step 61 ), the value of the variable t is updated to correspond to the current time (step 62 ). Following this, it is examined at step 63 whether TAT is lower than said time. If that is the case, the variable TAT is updated with the value t (step 64 b ), after which the process proceeds to step 65 b where a new TAT is calculated by adding the constant IAT to the previous value. Additionally, the variable pass is given the value true (T).
If it is detected at step 63 that the value of the variable TAT is not lower than the time corresponding to the arrival time of the traffic unit, the process proceeds to step 64 a where it is examined whether the value of TAT is higher than t+L (i.e. whether the traffic unit has after all arrived before the instant of time TAT-L). If that is the case, the variable pass will be given the value false (F) at step 65 a. If that is not the case, the process in turn proceeds to step 65 b where a new TAT is calculated by adding the constant IAT to the previous value. In addition, the variable pass is given the value true (T). From steps 65 a and 65 b, the process proceeds to the final step (step 66 ) where the value of the variable pass is returned.
In the mechanism described above, the calculated TAT hence corresponds to the counter value of the preceding examples, the value in question being indicative of the “pool size” at the arrival moment of each traffic unit. In this case, then, the “counter” has no upper limit (as time goes on). As can be seen, the methods above are similar to one another: the term (L/IAT) in a way corresponds to the pool size B and the term (H−L)/IAT in a way corresponds to D.
The modification into a low-pass filter according to the invention takes place as in the above by adding into the rejection branch an extra step 65 c (FIG. 7 a ) where the value of the variable TAT is updated so that the updated value equals the lower of the values TAT+IAT and t+H. In this case, too, updating the variable TAT continues in the rejection branch in the same manner as in the acceptance branch (at step 75 b ), but t+H is the highest value accepted for TAT. The “debt range” in this example is created by shifting, in case of heavy traffic, the TAT further away rejected-traffic-unit by rejected-traffic-unit, but not further away than distance H from the current time instead of not carrying out the shift at all for rejected traffic units.
In the examples according to FIGS. 6 and 7 a, the theoretical arrival time TAT is the quantity which is varied according to traffic density. A traffic density lower than the limit value (U) causes a relatively smaller increase in the TAT value than does a traffic density higher than the limit value.
The operation illustrated in FIG. 7 a may also be implemented by an apparatus such as illustrated in FIG. 7 b, the apparatus substantially corresponding to the one in FIG. 3 b. Upon arrival of a new traffic unit, the decision-making unit DM controls the clock CLK to store the current time in the memory M 1 , after which it compares the values of the variables t and TAT (and if necessary the values of the variables t+L and TAT) to each other. Following this, the DM updates in accordance with FIG. 7 a a new value for the theoretical arrival time, and supplies a pulse to either the output PASS or the output GAP depending on whether the traffic unit was accepted or not.
How large a “debt range” to choose depends on the characteristics desired for the gapping gate. The larger the “debt range” (i.e. the higher is D or H) the larger the debt for the traffic stream and the smaller number of traffic units will be accepted. This is indicated by FIG. 3 c: the larger the “debt range” the steeper is the transition at the limit value U in the characteristics curve of the gate. On the other hand, the larger the “debt range” the longer it takes before the gate responds to a abrupt change in the traffic rate when that change is from a very high to a less than U rate. For example, if U=10 tokens per second, D=20 tokens and r=100 cells per second, after which r suddenly drops to r=5 cells per second, it takes 4 seconds for the gate to be out of the 20 token “debt”. Only after this can the gate accept incoming traffic units. It is preferred that the limits (L, −D, H) and the distances between them be integers. A “rule a thumb” is that the relation (taken from either direction) between the size of the debt range and the size of the pool should be an integer. An advantageous special case is such where the debt range has a size equal to the pool size.
The method of the invention can also be implemented by e.g. a buffer served according to a FIFO principle (First In, First Out). Such an implementation is illustrated in FIG. 8 . The traffic units, such as cells, are stored in a buffer 81 in a queue in the order of their arrival. When the queue is not empty, the traffic rates are read out from the head of the buffer at the rate U (traffic units per second). If the average rate of arrival is higher than U, the number of traffic units in the queue will increase. The traffic units that arrive when the queue is full will be rejected.
The traffic stream may be applied to e.g a trigger block 84 which generates a pulse per each incoming traffic unit. The buffer is provided with a counter 83 which obtains information corresponding to the traffic rate from the trigger block and by means of the pulses continuously calculates the free space in the buffer. Every traffic unit entering the queue decrements the counter and every traffic unit read out from the queue by the server 82 increments the counter. In case the queue is full, the rejected traffic units decrement the counter reading up to the limit −D (where D is a positive integer). If the counter has a value lower than zero, no traffic units will be read out from the buffer but the value of the counter increments at the rate U.
The parameter values used in the method of the invention are chosen on the basis of the traffic source type. (If the type is unknown, it will be given a default type.) Let us assume that the rate r of the traffic source is constant and corresponds exactly to the limit value U. This means that the pool size remains unchanged, for example it is zero. If the rate of the source changes to be higher than U for a short while and then drops back to U, the traffic stream is in constant debt for as long as a similar change takes place in the opposite direction. In cases of constant rate traffic sources, it is therefore advantageous to give the pool a positive initial size and to set the limit value U slightly larger, for example one percentage unit larger than the rate requested by the source at the connection set-up stage.
The filter (gapping gate) according to the invention may also be used together with a conventional filter; in a normal traffic situation a conventional filter is used, but in situations of overload a switch is made to employ the low-pass filter of the invention.
The filter may also be used so that the cells to be forwarded are designated according to their priority to e.g. two categories. This may be done with the aid of a CLP bit (Cell Loss Priority), for example. Only low priority cells are filtered whereas higher priority cells are not filtered at all. Alternatively, the high priority cells may be considered transparent from the point of view of the filter, in other words they are not counted at all, whereby the high priority traffic has no influence on low priority traffic
Although the invention is above described with reference to the examples of the accompanying drawings, it is obvious that the invention is not restricted thereto but may be modified within the scope of the inventive idea disclosed above and in the attached claims. For example, in the embodiment in which a new theoretical arrival time is continuously calculated, any other linearly increasing quantity may be used instead of time. For reasons of simplicity, however, the attached claims (claim 4) refer to time. | The invention relates to a method for traffic control in a communication system transferring traffic units. The invention includes maintaining a continuously changing quantity determining whether an individual traffic unit can be forwarded, changing the value of the quantity so that a traffic density lower than a specific predetermined value changes the value of the quantity in a first direction, but no more than up to a predetermined first limit, and a traffic density higher than said predetermined value changes the value in a second direction. Further, the inventing relates to rejecting traffic units as the value of the quantity in said second direction reaches a specific predetermined second limit. In order to save the network bandwidth, the value of the quantity is also changed for the rejected traffic units in the second direction, but no more than up to a specific predetermined third limit, and when the value of the quantity is between the second and the third limit, it must again alter in said first direction up to at least the second limit before traffic units are accepted. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for applying solid developer particles to the recording element of a non-impact printer.
2. Description of the Prior Art
In present-day data processing equipment, fast printers are finding increasing application, in which the printing of the characters is effected without requiring raised type impacting on a recipient sheet of paper. These printers, called non-impact or strikeless transfer printers, ordinarily comprise a recording element which usually consists of a rotary drum or an endless belt, on the surface of which sensitized areas can be formed by electrostatic or magnetic means. These sensitized areas are also called latent images and correspond to the characters or images to be printed. These images are then developed, that is to say, made visible, with the aid of a powdery developer deposited on the recording element, and which is only attracted by the sensitized areas thereof. Thereupon, this recording element is brought into contact with a sheet of paper so as to permit the developer particles that have been deposited on these areas to be transferred onto this sheet in order to be fixed definitively thereon.
To apply this powdery developer to the recording element of a printer of this type, various applicator means have been used. For example, a device has been employed which comprises a housing containing the powdery developer, said housing having an opening past which moves the recording element. The inking of the recording element is effected by means of a cylindrical brush which, turning within the housing, projects the developer particles onto the surface of the element moving past said opening. This device has not given complete satisfaction due to the fact that it causes the formation of a cloud of developer particles which spreads on the outer surface of the case. Such clouds are particularly disagreeable for persons who are near the printer and who are attached by this cloud. Another problem with such devices is that they cause an undesirable electrification of the particles which, projected onto the recording element, can continue to exist on the areas that have not been sensitized by the recording element as a result of electrostatic attraction.
If the developer is capable of being attracted magnetically, a magnetic roller of the type as described and shown in French patent 1,566,007 and comprising a set of elongated magnetic elements, one arranged beside the other about a shaft parallel thereto, can be utilized to apply this developer. Each of these magnetic elements is magnetized radially so as to exhibit a constant magnetic polarity throughout the length thereof. The magnetic polarities exhibited by two adjacent magnetic elements have opposite signs. This magnetic roller, which has given good results when used in an apparatus for developing latent images with electrostatic charge for transporting a powdery developer which is capable of being attracted magnetically, has not been completely satisfactory when used as a roller for conveying a powdery developer in an apparatus for developing magnetic latent images such as, for example, a magnetic printer. Indeed, due to the fact that this magnetic roller is placed in the immediate vicinity of the element for recording latent images, this recording element is necessarily subject to the action of the magnetic fluxes generated by the magnetic elements of this roller. As a result, the information recorded on this recording element runs the risk of being substantially altered at the moment when it moves past this roller for applying the developer.
This latter drawback can be overcome by inserting between the applicator roller and the recording element a deflector intended to collect the developer particles conveyed by the roller. The deflector has one of its edges arranged in the immediate vicinity of the recording element so as to form therewith a trough having substantially the shape of a dihedral, in which the developer particles collected by the deflector will be gathered. Thus, an applicator means is obtained of the type described and shown in French patent No. 2,408,462 and in which the recording element is moved in a direction such that the collected particles in the trough are carried to the angle of the dihedral. The particles carried beyond said angle remain applied only to the sensitized areas of the recording element. However, it has been noted that if the applicator means contains a conveyor roller of the type as described in the aforementioned French patent No. 1,566,007, the developer particles would be aligned along the external magnetic lines of force which, on the surface of the conveyor roller, extend from each one of the magnetic elements with a magnetic north polarity to each one of the neighboring magnetic elements with a magnetic south polarity. Since these external field lines form arches which are oriented perpendicularly to the roller's axis of rotation, the developer particles, placed along these field lines, form chains of particles which are arranged perpendicularly to said axis. Under these circumstances, when these particle chains are stopped during passage by the baffle plate, they break up, but continue to form within the trough, fragments of chains having an orientation which is substantially perpendicular to the surface of the recording element. The result is that these particles, when they are applied to the sensitized areas of this element, have the tendency to enter into combination with one another so as to form thread-like aggregates of particles resulting in the appearance of trains of particles on the surface of the recording element and, thus, in trains that are particularly disagreeable to behold for the characters formed during the transfer of these particles to the paper.
SUMMARY OF THE INVENTION
The present invention overcomes this disadvantage and proposes a device which enables developer particles to be applied to the recording element of a non-impact printer without causing either an alteration of the information recorded on this element, or trains of particles on the surface of this element.
More particularly, the present invention relates to a device for applying to the recording element of a non-impact printer solid developer particles contained in a tank. Said device comprises, on the one hand, a conveyor roller arranged such as to bring these particles near the surface of this element and, on the other hand, a deflector inserted between this element and the conveyor roller to collect the particles conveyed by this roller. Said deflector has one of its edges arranged in the immediate vicinity of said element in order to form therewith a trough having substantially the shape of a dihedral and in which are gathered the particles thus collected. The recording element is moved in a direction so as to carry these particles to the angle of said dihedral, the particles that are carried beyond said angle remaining only applied to the sensitized areas of said recording element. The invention is characterized in that, since the developer is capable of being attracted magnetically, the conveyor roller is formed of a rotary cylinder which is coated on its outer cylindrical surface with strips of magnetic material arranged in side by side relation parallel to the rotational axis of said cylinder. Each one of said strips is magnetized such as to have on the outer surface thereof magnetic poles which form equidistant magnetic lines whose magnetic north or south polarity alternates from one magnetic line to the other. The magnetic lines extend in the direction of portions of helices with a constant pitch, the helices being so arranged that on two adjacent strips the pitch of the helix portions of one of these two strips is the reverse of that of the helix portions of the other strip.
BRIEF DESCRIPTION OF THE DRAWINGS
The nature of the present invention and the various features, details and advantages thereof will be better understood from the ensuing description given by way of non-limitative example and taken in connection with the accompanying drawings, in which:
FIG. 1 is a partial schematic view of a magnetic printer equipped with a developer-applicating device constructed according to the present invention;
FIG. 2 is a scaled-up schematic view showing certain details of the embodiment of the applicator means of FIG. 1;
FIG. 3 is a perspective view, with some parts broken away, of a magnetic roller as is known from the prior art for applying a developer to the recording element of a magnetic printer, said view showing the manner in which the developer particles orient to the roller surface;
FIG. 4 shows a first embodiment of a magnetic roller forming part of the application means which equips the printer shown in FIG. 1;
FIG. 5 shows a second embodiment of a magnetic roller forming part of the applicator means which equips the printer shown in FIG. 1; and
FIG. 6 is a perspective view, partially in section, according to a plane which is perpendicular to the rotational axis of a part of the roller shown in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The printer, one part of which is shown schematically in FIG. 1, comprises a recording element which, in the example described herein, consists of a magnetic drum 10. The magnetic drum 10 is rotated in the direction of arrow F by an electric motor (not shown). The recording of the information on this drum is effected by a magnetic recording element 11 which is located near the drum's outer surface. In the example described, this recording element 11 is composed of a group of devices including several magnetic recording heads which, arranged side by side, are brought into line parallel to the rotational axis 12 of drum 10. Each of these recording heads generates, when it is energized repeatedly by an electric current, a variable magnetic field, which results in the creation of magnetic domains or "magnetic points" on the surface of the drum which moves past the recording element 11. The instants of excitation of these heads are determined in known fashion so as to obtain on the drum's surface groups of magnetic domains 13, called magnetized areas or magnetic latent images, whose shapes correspond to those of the characters to be printed. These magnetized areas 13 then move past the window of an applicator means 14 which is located below drum 10 and which enables particles of a powdery developer contained in a tank 15 to be applied to the drum's surface. The developer particles, which are thus applied to drum 10, adhere in principle only to the magnetized areas thereof, so that the magnetized areas which ave moved past the applicator means 14 appear coated with a developer layer which forms on drum 10 the image of the characters to be printed.
It should be mentioned here that this developer consists of magnetic particles which are coated with a thermoplastic resin which, through heating, is capable of melting and of being fixed on a sheet of paper on which it has been deposited. By way of example, the developer contained in tank 15 may be that which has been described in the patent application filed in France by the applicant on Mar. 20, 1980 and published under No. 2,478,839. As indicated hereinabove, this developer, which is applied to drum 10, adheres mainly to the magnetized areas 13, thus forming deposits 16 of particles on the drum's surface. These deposits 16 are then carried past a retouching device 17 whose function is to eliminate the particles that have adhered to locations other than the magnetized areas 13, as well as the particles that are in excess on said areas. Whereupon almost all of the developer particles that continue to exist on drum 10 are transferred to a sheet of paper 18 which is applied to drum 10 by means of a pressure roller 19. The residual developer particles which, when this transfer takes place, are still on drum 10, are then dislodged by means of a cleaning device 20 known in the prior art, e.g., a brush. Thereupon, the magnetized areas which have moved past the cleaning device 20 move past an eraser 21 where they are erased. This allows the demagnetized portions of drum 10 to be remagnetized when they move past the recording element 11 as a result of continued rotation of the drum.
As can be seen from FIG. 1, the applicator means 14 comprises, on the one hand, a conveyor element 22 which takes away developer particles in tank 5 in order to bring them near the surface of drum 10 and, on the other hand, a stationary baffle plate or deflector 23 positioned between conveyor element 22 and drum 10 in order to cause the particles conveyed by element 22 to be collected and applied to the surface of drum 10. An applicator means 14 of this type has especially been described and shown in French patent No. 2,408,462.
The conveyor element 22 of such an applicator means 14 is ordinarily composed of a magnetic roller 22 having a rotational axis 24 parallel to the rotational axis 12 of drum 10. The baffle plate or deflector 23 associated with magnetic roller 22 is a component which is affixed to the two side surfaces of tank 15, and has, as can be seen in FIG. 2, a plane surface 40 delimited by a first and a second edge 41 and 42, respectively, parallel to axes 12 and 24. The second edge 42 preferably forms a sharp corner so as to avoid an accumulation of particles on said edge. The baffle plate or deflector 23, whose first edge 41 is practically in contact with magnetic roller 22, is located in such a way that its second edge 42 is in the immediate vicinity of the surface of drum 10 and that its face 40 forms with the plane delimited by axis 12 of the drum and the axis 24 of the magnetic roller a dihedral whose angle is less than 45 degrees.
Magnetic roller 22 is rotated in the direction indicated by arrow R in FIGS. 1 and 2 by means of an electric motor (not shown). This direction is such that the developer particles conveyed by magnetic roller 22 are carried to face 40 of baffle plate or detector 23 and are stopped or removed from the roller during passage of the roller surface past edge 41 of the baggle plate, at least the majority thereof. The particles which are thus removed then collect in a trough 43 delimited by the surface of drum 10 and face 40 of baffle plate 23. The direction of rotation of drum 10, indicated by arrow F, is chosen such that the particles collected in trough 43 are carried to the edge or corner 42 of baffle plate 23 so that some of the particles can be applied to the magnetized areas 13 of drum 10. The particles applied to areas 13 and thus carried by drum 10 as it continues its rotation are not stopped by baffle plate 23 because of the fact that the baffle plate is spaced slightly away from the drum so that it does not touch the drum. The space or opening between sharp corner 42 and drum 10 is of a width sufficient to enable the developer particles carried by the drum to leave the trough 43. The developer particles applied to the magnetized areas of the drum exit from trough 43 and continue to adhere to these areas and thus make visible the characters to be printed. Those particles that leave trough 43 without being retained by the drum usually fall back into tank 15.
The magnetic roller which has been shown with certain parts broken away in FIG. 3 is known from the prior art and has been described in French patent No. 1,566,007. It will be recalled that this roller comprises a stationary shaft 25 made of a material with great magnetic permeability such as, for example, soft iron. Magnetic elements 26 are placed side by side around shaft 15 parallel thereto so as to form a ring around this shaft. To simplify the drawing, only two magnetic elements 26A and 26B are depicted in FIG. 3, but it should be pointed out that the number of these elements is well above two. This number has been chosen so that it can be a multiple of two. Thus, for example, in the example shown in FIG. 3, the roller comprises eight magnetic elements.
The roller of FIG. 3 also has a cylindrical sleeve 27 laced around the ring formed by the magnetic elements and mounted such as to turn about shaft 25 in the direction indicated by arrow R in FIG. 3. This sleeve is made of non-magnetic material such as, for example, aluminum.
As can be seen in FIG. 3, the magnetic elements 26 are magnetized radially, that is to say, in a direction perpendicular to axis 24 so that each magnetic element has on its face 28 situated opposite sleeve 27 a magnetic polarity of opposite sign when one goes from one magnetic element to the next magnetic element. Thus, for example, if magnetic element 26A in FIG. 3 has on its face situated opposite sleeve 27 a magnetic north polarity (N), magnetic element 26B adjacent to element 26A has on its face 28 situated opposite sleeve 27 a magnetic south polarity (S). Under these circumstances, the external field lines of the magnetic field generated by magnetic elements 26 extend from faces 28 with magnetic north polarity to faces 28 with a magnetic south polarity.
In FIG. 3, only some of these external field lines 29 are indicated by a dash-dotted line to simplify the drawing. If the magnetic roller described above is brought into contact with a powdery developer which is capable of being attracted magnetically, the outer surface of sleeve 27, as it rotates, will be covered with a layer of developer particles. During this operation, some of the developer particles will adhere directly to the surface of sleeve 27, while others will be placed outside said surface along external field lines 28 so as to form particle chains, some of which (30) in FIG. 3 are curved in the form on an arch, while others (31) are curved in the form of a partial arch oriented substantially perpendicularly to the surface of the sleeve. Thus, as can be seen in FIG. 3, all the particle chains are contained in planes which are perpendicular to rotational axis 24 of the roller. The result is that the developer particles that have been deposited on this sleeve are stopped by baffle plate 23 and continue to form chains or fragments of chains 32 which will pile up on face 40 of baffle plate 23, one remaining substantially parallel to the other, as can be seen in FIG. 3. These particles, which thus enter into combination with one another, form, when they are subsequently applied to the surface of drum 10, thread-like aggregates of particles which not only cover the magnetized zones of this drum, but spill over even beyond these areas so that, when these aggregates are then transferred onto the paper 18, they form trains of particles which greatly impair the quality of the print.
The magnetic roller of the present invention overcomes this drawback. In the embodiment shown in FIG. 4, magnetic roller 22 takes the shape of a cylinder 50 having a shaft 51 which enables it to swivel in bearings (not shown) mounted on the side faces of tank 5. The bearings are so arranged that the rotational axis 24 of roller 22 is parallel to the rotational axis 12 of drum 10. Cylinder 50 is made of non-magnetic material such as, for example, copper, glass, or even a plastic material. In the example described herein, it is assumed that cylinder 50 is made of aluminum.
FIG. 5 shows that the outer surface of cylinder 50 is coated with strips 52 of magnetic material, the strips are positioned adjacent to one another and parallel with the rotational axis 24 of cylinder 50.
In the example of FIG. 4, six strips 52 are thus arranged on cylinder 50, with each strip extending throughout the length of the cylinder. The flexible magnetic material of which these strips are made is well known in the art and usually consists of an elastomer into which magnetic particles have been incorporated. Thus, this flexible magnetic material can be of the type mass-produced by Produits Chimiques Ugine-Kuhlmann under the trade name of "Ferriflex" (registered mark).
As can be seen in FIG. 6, which shows in section, according to a plane that extends through rotational axis 24, a portion of the magnetic roller of FIG. 5, each of strips 52 is magnetized permanently in a direction perpendicular to its thickness so as to have on its outer surface magnetic poles that form magnetic lines such as 53A, 53B, 53C which are equidistant from one another. The magnetic north or south polarity of said lines alternate from one magnetic line to the other. Thus, for example, magnetic lines 53A and 53C shown in FIG. 6 have a magnetic north polarity (N), while magnetic line 53B has a magnetic south polarity (S).
In FIGS. 4, 5 and 6, these magnetic lines have been shown symbolically by broken lines and are generally denoted by the reference numeral 53 in FIGS. 4 and 5. The equidistance of these magnetic lines depends on the thickness of strip 52. It is pointed out, by way of example, that if the strip is 1 mm thick, these magnetic lines 55B are separated from one another by a distance of 2.54 mm, and that if the strip is 2 mm thick, these magnetic lines are separated from each other by a distance of 5.08 mm.
FIG. 5 shows that these magnetic lines 53 are oriented to the surface of the magnetic roller according to the helix portions with the same pitch, one of said helices (H) being indicated by a dash-dotted line in FIG. 4. In a particularly advantageous embodiment, pitch P of these helices is chosen such as to be numerically equal to the length D of a cross section of cylinder 5, D being the diameter of said cylinder. Under these circumstances, the angle at which magnetic lines 53 intersect the generators of the cylinder is equal to 45 degrees. It is also pointed out that, as can be seen in FIG. 4, the portions of the helices formed by the various magnetic lines 53 do not all have the same direction of winding. In other words, the pitch of these portions of helices is such that on two adjacent strips 52 the pitch of the portions of helices of one of these two strips is the reverse of that of the portions of helices of the other strip. The number of strips 52 placed on cylinder 5 is chosen such as to be even at all times, so that the characteristic which has just been mentioned concerning the pitch of the portions of helices can always be complied with.
It will be better understood that various embodiments of the magnetic roller of the invention can be contemplated. Thus, in the embodiment of FIG. 5, strips 52 of flexible material each have a length less than that of cylinder 50. In the special case depicted in FIG. 5, the length of each of the strips 52 is equal to half that of cylinder 5 so that, when two of these strips, which are oriented in such a way that their broad side is parallel to the rotational axis 24 of the cylinder, are placed end to end on this cylinder, touching each other with their narrow side, the two bands or touching strip extend throughout the length of the cylinder. Put differently, if cylinder 50 is assumed to be divided, perpendicularly to its rotational axis 24, into two portions 50A and 50B of equal length, each of these cylinder portions is covered with 2 n strips, 2 n being an even number. In FIG. 5, the strips covering the portion of cylinder 50A are denoted by 52A and those covering the portion of cylinder 50B by 52B. It can also be seen in FIG. 5 that the pitch of the portions of helices according to which magnetic lines 53 of strips 52A and 52B are oriented such that on two adjacent strips, the pitch of the portions of helices of one of these two strips is the reverse of that of the portions of helices of the other strip.
It should also be mentioned that in the more general case where cylinder 50 is assumed to be divided, perpendicularly to its rotational axis 24, into p equal portions and where the length of each of the strips 52 of magnetic material equals the length of each of these p cylinder portions, each of these p cylinder portions is covered with an even number (equal to 2 n) of strips 52. The 2 n strips covering each of the p cylinder portions are adjacent to one another and run parallel to the rotational axis of the cylinder. In addition, the 2 n strips of the same cylinder portion are, in turn, adjacent to the 2 n strips of the adjacent cylinder portion and are aligned therewith.
Strips 52 of magnetic material which cover cylinder 5 are not necessarily made of flexible material that incorporates magnetic particles. Thus, in one embodiment, these strips 52 can be made of a magnetic non-flexible material, for example, ferrite, molded such as to take the form of a hollow cylinder (or portions of a hollow cylinder, such as, for example, 52), whose inner diameter corresponds to the outer diameter of cylinder 50, said hollow cylinder being magnetized so as to have, on its outer face, magnetic poles that form magnetic lines which extend according to portions of a helix placed in the same way as that shown in FIGS. 4 and 5.
By using the magnetic roller described above in a device of the type described in French patent No. 2,408,452, it was indeed determined no developer particles were bundled into chains within the trough formed by the baffle plate and the recording element and that, as a result, the subsequent transfer of these particles onto the paper practically did not result in trains of particles, so that the print quality was greatly improved.
While particular embodiments of the invention have been shown and described, it will be understood that the invention is not limited to these embodiments which have been set forth for purposes of illustration only. On the contrary, it includes all the means that constitute technical equivalents to those shown and described herein, taken separately or jointly and carried into effect within the scope of the appended claims. | The invention relates to magnetic printers and, more particularly, to an apparatus for applying solid developer particles to the recording drum of a non-impact printer. This apparatus comprises, on the one hand, a conveyor roller (22) which brings the developer particles from a particle storage or supply tank (15) to the vicinity of the recording drum (10) and, on the other hand, a baffle plate or deflector (23) positioned between the roller (22) and the drum (10). The roller (22) is coated with magnetized strips having on their outer surfaces magnetic helicoidal lines such that on two adjacent strips the pitch of the magnetic lines of one strip is opposed to that of the other strip. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Design patent application Ser. No. 29/479,014, filed Jan. 10, 2014, and entitled “Dry Fire Practice Magazine Block,” the entire contents of which are incorporated herein by reference.
FIELD OF THE DISCLOSURE
The present disclosure relates to firearms, and more particularly to dry-fire practice equipment.
BACKGROUND
Dry fire practice involves manipulating and using the weapon without loading it. The technique is often used to simulate actual firing of the firearm when there is not a suitable place to practice with live ammunition. The user may handle, aim, pull the trigger, pull the slide and/or cock the firearm during such practice. Dry fire exercises are a versatile and safe way to practice with firearms and improve one's shooting skills. Historically safety or “dummy” rounds have been used to simulate proper loading, reloading, and quick trigger engagement after reloading. However it is laborious and time consuming to load the practice magazine and then have to retrieve the ejected safety rounds from the ground. Most pistols use magazines featuring a spring loaded follower. When the magazine is emptied, the follower engages a slide lock which prevents travel of the slide until a new, loaded magazine is inserted. While this functionality is useful for quickly reloading the firearm during live firing, it hampers practicing with the firearm because the operator must disengage the slide lock after insertion of a fresh magazine. If that magazine is empty the spring loaded follower prevents the disengagement of the slide stop. As mentioned above the historic use of safety rounds is problematic.
Some pistols, such as the Smith & Wesson M&P9c pistol (available from Smith & Wesson Corp. of Springfield, Mass.), contain a magazine safety. Such pistols cannot function without a magazine, preventing the most basic practice of cycling the slide to cock the firearm and then pulling the trigger. Using an empty magazine automatically locks the slide back with each cycle, which hinders the drill. Thus use of safety rounds is very inefficient.
Devices are known which facilitate using a firearm to practice.
U.S. Pat. No. 119,357, issued to A. C. Hobbs on Sep. 26, 1871, discloses a black cartridge containing no gun powered. The cartridge includes a rubber disk positioned at the rear of the cartridge casing. During dry fire practice, the Hobbs blank is chambered and the disk absorbs blows from the firing pin, allowing the user to simulate some firing actions.
Improvements on the Hobbs blank are known, such as the firearm snap cap disclosed in U.S. Pat. No. 5,435,090 issued to J. E. Darrow on Jul. 25, 1995. The snap cap is also designed to be chambered and consists of a bore cleaning brush attached to a unit body having a diameter equal to the diameter of ammunition used with the firearm.
While the Hobbs blank, the Darrow snap cap, and other types of chamber-able simulated ammunition may be used during dry fire practice, such practice ammunition may be expelled prematurely if the firearm's round ejection mechanisms are simulated (e.g., pulling a pistol slide back when a practice round is in the chamber). Thus, practicing actuating the firearm slide, reloading the firearm magazine, and other techniques may be difficult and/or require multiple rounds of practice ammunition.
Other safety devices are known, such as the magazine block device disclosed in U.S. Pat. No. 7,240,449 issued to N. E. Clifton on Jul. 10, 2007. The Clifton magazine block is designed to be inserted into a magazine and, when the magazine is loaded into a rifle, the magazine block occupies the loading chamber, thereby preventing live rounds of ammunition from being loaded while still allowing the user to practice with the rifle. Some designs of the Clifton magazine block impede full motion of the firearm slide and/or charging handle.
Given the foregoing, what are needed are devices which allow a user to conduct dry fire practice drills with a firearm, including magazine removal are reload exercises.
BRIEF SUMMARY OF THE INVENTION
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. It is not intended to identify key features or essential features of the subject matter to be claimed, nor is it intended to be used to limit the scope of the subject matter to be claimed.
The present disclosure is directed to magazine block devices. Magazine block devices in accordance with the present disclosure may be used with pistols, rifles, and other firearms during dry fire practice, enabling a user to learn and maintain proper firearm handling skills without expending ammunition, thus reducing costs and increasing safety during such exercises,
In an aspect, a magazine block device is provided having a bullet-shaped body. The magazine block device is designed to be inserted into a magazine having an offset, spring-loaded follower. The magazine block device body includes two upper ridges positioned along to outer edge of the body. The upper ridges form a longitudinal channel through which the firearm breath face loading tab may pass without dislodging the magazine block device. The upper ridges contact the feed lips of the magazine, keeping the magazine block device in position.
Magazine followers are often angled, therefore the bottom portion of the magazine block device may comprise an offset lower ridge. The lower ridge is configured to evenly force the follower down a sufficient distance to prevent actuating the firearm slide lock. This allows dry fire practice of pulling the slide,
The magazine block device may also comprise one or more cutouts, protrusions, or other portions designed to help a user insert or remove the magazine block device from the magazine. In some aspects, the magazine block device may be inserted and removed from a magazine by hand, enabling the user to quickly prepare a firearm for dry fire practice and return the firearm to live, operational status by simply inserting a magazine containing live ammunition or removing the magazine block device from a magazine, reloading that magazine with ammunition, and loading the magazine into the firearm.
In an aspect, the magazine block device allows the user to dry fire practice with a semi-automatic pistol without having the slide lock engage. Because dry fire practice necessitates having the pistol or other firearm free of ammunition in the magazine as well as the chamber, the built in slide lock will always lock the slide in the rear, or open, position when the pistol is cycled, or re-cocked, to reset the trigger into the “fire” position. This requires the user to disengage the slide lock after every cocking cycle which is disruptive to dry fire practice techniques. Among other things, having to constantly disengage the slide lock after every trigger pull and recock cycle disrupts the hand position, target focus and mental concentration.
The slide lock is a feature in all semi-automatic pistols to alert the user when the magazine is empty or all rounds have been expended. After the last round in the magazine is chambered, the magazine follower rises to the top of the magazine, by spring pressure, until it engages the feed lips of the magazine body. When in this upper-most position, the magazine follower pushes up on the slide-lock of the pistol so that after the next shot and recocking cycle, the slide of the pistol engages this slide lock and holds the slide in its most rearward, or open, position.
In an aspect, a magazine block device prevents the slide lock from engaging by simulating a round in the feed position in the magazine. This pushes the magazine follower down low enough as to prevent engagement of the slide lock, allowing the slide to return to the closed, or locked, position. The user only need manually cycle the slide of the pistol after each “dry fire” trigger pull with the magazine block device installed, avoiding the extra, disruptive step of disengaging the slide lock.
Further features and advantages of the devices and systems disclosed herein, as well as the structure and operation of various aspects of the present disclosure, are described in detail below with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present disclosure will become more apparent from the Detailed Description set forth below when taken in conjunction with the drawings in which like reference numbers indicate identical or functionally similar elements.
FIG. 1 is a top perspective view of a dry fire practice magazine block device, in accordance with the present disclosure.
FIG. 2 is a bottom perspective view of the magazine block device of FIG. 1 .
FIG. 3 is a perspective cutaway view of a firearm detailing the firearm internal components, having a round loaded in the magazine but not chambered.
FIGS. 4A & B are cutaway views of the firearm of FIG. 3 , wherein the slide has been pulled back in order to chamber the round and the slide lock being disengaged.
FIGS. 5A & B are cutaway views of a firearm detailing the firearm internal components wherein no round is present and the slide lock is engaged.
FIGS. 6A-C are perspective views of a magazine and a magazine block device being inserted into the magazine, in accordance with an aspect the present disclosure.
FIGS. 7A & B are cutaway views of a firearm wherein the firearm magazine houses a magazine block device preventing the slide lock from engaging.
FIGS. 8A & B are cutaway views of a firearm wherein the firearm magazine houses a magazine block device preventing the slide lock from engaging and the slide and barrel being removed.
FIG. 9 is a cutaway view of a firearm wherein the firearm magazine houses a magazine block device preventing the slide lock from engaging.
FIGS. 10A & B are cutaway views of a firearm wherein the firearm magazine houses a magazine block device preventing the slide lock from engaging, thereby allowing the slide to return after being pulled back.
FIG. 11 is a cutaway view of a firearm wherein the firearm magazine houses a magazine block device.
FIG. 12 is a rear top perspective view of a dry fire practice magazine block device, in accordance with an aspect of the present disclosure.
FIG. 13 is a front top perspective view thereof.
FIG. 14 is a front bottom perspective view thereof.
FIG. 15 is a rear bottom perspective view thereof.
FIG. 16 is a left side elevational view thereof,
FIG. 17 is a right side elevational view thereof.
FIG. 18 is a rear end view thereof.
FIG. 19 is a front elevational view thereof.
FIG. 20 is a front plan view thereof.
FIG. 21 is a bottom plan view thereof.
FIG. 22 is a rear top perspective view of another aspect of the dry fire practice magazine block device.
FIG. 23 is a front top perspective view thereof.
FIG. 24 is a front bottom perspective view thereof.
FIG. 25 is a rear bottom perspective view thereof.
FIG. 26 is a left side elevational view thereof.
FIG. 27 is a right side elevational view thereof.
FIG. 28 is a rear end view thereof.
FIG. 29 is a front elevational view thereof,
FIG. 30 is a front plan view thereof,
FIG. 31 is a bottom plan view thereof.
DETAILED DESCRIPTION OF THE INVENTION
The present disclosure is directed to magazine block devices for dry fire practice. Devices in accordance with the present disclosure allow users of pistols, rifles and other firearms to conduct dry fire practice while having the firearm free of any ammunition in the magazine, as well as the chamber. Magazine block devices in accordance with the present disclosure prevent the firearm slide lock from engaging after every cocking cycle. Such devices also remain engaged within the device after each cocking cycle, even where such cycles are designed to expel chambered ammunition casings and/or dummy rounds.
Referring now to FIG. 1-2 , a top and a bottom perspective view of a dry fire practice magazine block device 100 are shown and described in accordance with various aspects of the present disclosure.
Magazine block device 100 may be constructed out of any appropriate material including, but not limited to, a polymer, metal, wood, rubber, and/or combinations thereof. Magazine block device 100 comprises a body 102 and may be bullet-shaped, resembling the profile of the ammunition magazine block device 100 that replaces an ammunition round during dry fire practice. The cross section of body 102 is substantially similar to the cross section of such ammunition. Body 102 may include a curved front portion 110 . Curved front portion 100 ensures that device 100 fits into magazines designed for bullets having similar profiles.
Two upper ridges 104 are positioned along the outer edge of body 102 . Upper ridges 104 extend vertically from body 102 . In some aspects, upper ridge 104 extends approximately two millimeters from the top surface of body 102 . As shown in greater detail in FIGS. 6-11 , upper ridges 104 are designed to simulate the side of a bullet casing and position device 100 properly within a magazine by contacting the feed lips of the magazine. Upper ridge 104 has a flat outer surface, a curved inner surface, and extends most of the length of device 100 . In some aspects, the front of upper ridge slopes downward, forming a smooth interface with other portions of body 102 .
Two ridges 104 form a longitudinal channel 106 along the top surface of device 100 . Channel 106 allows firearm loading mechanisms, such as a breach face loading tab of a pistol (see FIGS. 3-5 and FIG. 18 ) to freely move without chambering device 100 , a round, or any other item. This allows the user to perform dry fire exercises such as cocking the firearm without expelling device 100 .
Device 100 may be configured for use with spring loaded magazines having angled followers. Device 100 may further include a lower ridge 108 extending down from body 102 in order to contact the follower and maintain the follower in a position that will not actuate the firearm slide lock or other magazine reloading mechanism. In an aspect, lower ridge 108 extends approximately four millimeters downward and is offset relative to the longitudinal axis of device 100 . This configuration, shown in FIG. 1 , is configured to evenly force the follower down a sufficient distance to prevent actuating the firearm slide lock. This allows dry fire practice of pulling the slide freely and performing other recocking actions without actuating the slide release mechanism. Lower ridge 108 extends in a direction parallel to the longitudinal axis of device 100 . At a front portion, lower ridge 108 slopes upward, connecting with other portions of device 100 . The outer side of lower ridge 108 is substantially vertical. The inner side of lower ridge 108 may be curved in order to interface with the surface of the magazine follower.
Front portion 110 may include one or more flanges 112 extending inwardly toward the longitudinal axis of device 100 . Each flange 112 is raised slightly with respect to the surface of body 102 such that a user may push or pull against flange 112 in order to install or remove device 100 from a magazine. Flanges 112 may be positioned along other portions of device 100 , such as upper ridges 104 , body sides, and the like.
Device 100 may also comprise one or more cutouts, protrusions, or other portions designed to help a user insert or remove the magazine block device 100 from the magazine. In some aspects, the magazine block device 100 may be inserted and removed from a magazine by hand, enabling the user to quickly prepare a firearm for dry fire practice and return the firearm to live, operational status by simply inserting a magazine containing live ammunition or removing magazine block device 100 from a magazine, reloading that magazine with ammunition, and loading the magazine into the firearm.
In an aspect, body 102 may comprise pocket 114 . A tool or other rigid member may be inserted into pocket 114 in order to aid in the removal of device 100 from a magazine,
As will be apparent to those skilled in the relevant art(s) after reading the description herein, device 100 may be configured to function with firearms using various types of ammunition (e.g., 9 mm, .308, .45ACP, 12ga., .22LR, 5.56x45 mm, 7.62×51 mm, .357 Magnum), having varying magazine designs (e.g., single column, staggered, internal box, detachable box, STANAG magazine) and the like. Device 100 may be configured to inhibit round loading mechanisms and/or casing ejection mechanisms apart from those shown and described herein.
Referring now to FIGS. 3-5 , cutaway views of a firearm 300 are shown, depicting operations of portions of firearm 300 .
Pistol 300 includes a hammer 302 . Hammer 302 may be manually cocked or may be cocked by movement of a slide 308 . Slide 308 has a breach face loading tab 310 configured to push a round 304 into a firing chamber 312 from a magazine 306 . Before round 304 is loaded into chamber 312 , round 304 is held in place within magazine 306 by a pair of feed lips 406 and a follower 404 . Feed lips 406 constrain the motion of round 304 because follower 404 is spring loaded and forces round against feed lips 406 . Slide 308 can freely move unless a slide lock 402 is engaged. Slide lock 402 is engaged when no rounds 304 or other objects remain in magazine 306 , thereby allowing follower 404 to press against slide lock 402 . Engaging slide lock 402 locks slide 308 into an open position. In order to move slide 308 from the locked position a slide lock release must be pressed by the user. Pressing the slide lock release is not part of a normal firing sequence; therefore avoiding such an action during dry fire practice is desired. Device 100 may be utilized in order to avoid such an action because device 100 prevents upward movement of follower 404 , preventing follower 404 from engaging slide lock 402 .
Detail view 401 shows tab 310 positioned near the rear of round 304 . As tab 310 moves forward, it pushes round 304 out of magazine 306 and into chamber 312 .
Detail view 501 shows follower 404 engaging slide lock 402 when follower 404 is not vertically constrained by round 304 , device 100 , or another object.
Referring now to FIGS. 6A-C , perspective views of magazine 306 and device 100 are shown. In particular, FIGS. 6A-C shown how device 100 is inserted into empty magazine 306 in order to prepare magazine 306 for use in dry fire practice.
When follower 404 is in the position shown in FIG. 6A , slide lock 402 is activated. In order to avoid activating slide lock 402 during dry fire practice, vertical movement of follower 404 must be limited using device 100 .
As shown in FIG. 6B , follower 404 is first pushed down in direction A. Magazine block device 100 is then inserted above follower 404 in direction B. The edges of device 100 may be curved in order to push follower 404 down via insertion of device 404 as shown in FIG. 6B .
As shown in FIG. GC, upper ridges 104 each contact a feed lip 406 , maintaining the position of device 100 . Lower ridge 108 pushes follower 404 downward, ensuring that it cannot engage slide lock 402 when the magazine shown in FIG. 6C is in use.
Referring now to FIGS. 7A-8B , cutaway views of firearm 300 , wherein magazine 306 houses device 100 , are shown. Device 100 is inserted into magazine 306 as shown in FIGS. 6A-C . As shown in FIGS. 7A & B, magazine 306 is then inserted into firearm 300 as normal.
FIG. 7B is a detail view of area 701 . As show in FIG. 7B , when magazine 306 is equipped with device 100 , tab 310 moves freely through channel 106 . Tab 310 does not contact device 100 , therefore no object is loaded into chamber 312 and firearm 300 may be cycled may times during practice.
FIG. 88 is a detail view of area 801 of FIG. 8A . As shown in FIG. 8B , when magazine 306 is equipped with device 100 , follower 404 does not engage slide lock 402 .
Referring briefly to FIGS. 9-11 , a series of cutaway views are shown which depict the movement of slide 308 when firearm 300 is equipped with device 100 . Slide 308 is able to move freely, enabling firearm 300 to be used in dry fire practice without having to constantly disengage slide lock 402 after every trigger pull and re-cock cycle.
Referring briefly to FIGS. 12-21 , various views of a dry fire practice magazine block device 100 , in accordance with an aspect of the present disclosure, are shown.
Referring briefly to FIGS. 22-31 , various other views of another dry fire practice magazine block device 100 , in accordance with an aspect of the present disclosure, are shown.
While various aspects of the present disclosure have been described above, it should be understood that they have been presented by way of example and not limitation. It will be apparent to persons skilled in the relevant art(s) that various changes in form and detail can be made without departing from the spirit and scope of the present disclosure. The present disclosure should not be limited by any of the above described aspects, but should be defined only in accordance with the following claims and their equivalents.
In addition, it should be understood that the figures, which highlight the structure, methodology, functionality and advantages of the present disclosure, are presented as examples only. The present disclosure is sufficiently flexible and configurable, such that it may be implemented in ways other than that shown in the accompanying figures.
Further, the purpose of the foregoing Abstract is to enable the U.S. Patent and Trademark Office and the public generally and especially the scientists, engineers and practitioners in the relevant art(s) who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of this technical disclosure. The Abstract is not intended to be limiting as to the scope of the present invention in any way. | Magazine block device for firearm dry fire practice which allows a user to practice proper firearm handling skills without expending ammunition, including recocking and actuating the firearm slide without pressing the slide lock release. In an aspect, a magazine block device is provided having a bullet-shaped body, two upper ridges forming a longitudinal channel through which the firearm breach face loading tab may pass without dislodging the magazine block device, and an offset lower ridge. The lower ridge is configured to evenly force a magazine follower down a sufficient distance to prevent actuation of the firearm slide lock. This allows dry fire practice of pulling the slide. Several other features include ridges to assist a user to remove and load the block device in and out of a magazine, as well as a pocket to mechanically remove same. | 5 |
This is a continuation of 07/838,540, filed on Feb. 19, 1992, (now U.S. Pat. No. 5,213,684), which is a continuation of 07/150,246, filed Jan. 29, 1988, (now U.S. Pat. No. 5,098,565).
FIELD OF THE INVENTION
The present invention relates to filter apparatus and systems generally and to techniques for operating such apparatus and systems.
BACKGROUND OF THE INVENTION
Various types of filters are known for filtering water and similar liquids. A particularly useful type of filter is a disk filter. Filters of this type are described and claimed, for example, in applicant's U.S. patent applications Ser. Nos. 647,094, filed Sep. 4, 1984, which is now U.S. Pat. No. 4,624,785; 709,371, filed Mar. 7, 1985, which is now abandoned; 709,372, filed Mar. 7, 1985, which is now U.S. Pat. No. 4,683,060; 709,373, filed Mar. 7, 1985, which is now U.S. Pat. No. 4,654,143; and U.S. Pat. Nos. 4,026,806; 4,042,504; 4,045,345; 4,271,018; 4,278,540; 4,295,963.
SUMMARY OF THE INVENTION
The present invention seeks to provide an improved filter for use in filtering fluids, such as water.
There is thus provided in accordance with a preferred embodiment of the present invention, a disk-type filter comprising a housing having an inlet connectable to an upstream pipe and an outlet connectable to a downstream pipe and a stack of filter units disposed within the housing for separating solid particles from a fluid flowing between filter units in the stack of filter units from an upstream side of the stack of filter units to a downstream side thereof, characterized in that the stack of filter units includes a plurality of co-operating filter units defining a plurality of paired co-operating filter surfaces, including first and second surfaces each defining a plurality of fingers, the fingers defined by the first surface being arranged in registration with the fingers defined by the second surface, the exteriors of the fingers defined by the first and second surfaces communicating with either one of an upstream side and a downstream side and the interiors of the fingers defined by the first and second surfaces communicating with the other one of the upstream side or downstream side, spaces being defined in association with the fingers defined by the first and second surfaces and being disposed in registration so as to define channels, which permit particulate matter to become disengaged with the upstream side of the fingers defined by the first and second surfaces.
According to a further preferred embodiment of the present invention, there is provided a filter unit comprising first and second surfaces defining a plurality of fingers, spaces being defined in association with the fingers defined by the first and second surfaces such that when a plurality of filter units are disposed in registration, the spaces define channels.
Further in accordance with a preferred embodiment of the present invention, the fingers defined by the first and second surfaces each have formed thereon a pair of spaced, generally raised line portions separated by an interior area, the raised line portions on at least one of the first and second surfaces defining a plurality of spaced grooves.
Still further in accordance with a preferred embodiment of the present invention, the filter also comprises a filter aid operatively associated with the stack of filter units.
Additionally in accordance with a preferred embodiment of the present invention, the pluralities of spaced grooves defined by the first and second surfaces define an enhanced depth filtering pathway.
Still further in accordance with a preferred embodiment of the present invention, there is provided a planar divider at the interior area of each of the fingers, such that when a plurality of filter units are disposed in registration, the line portions and the planar dividers define a multiplicity of backflow chambers for enhanced backflowing.
Further in accordance with a preferred embodiment of the present invention, the stack of filter units comprises a generally cylindrical element having an axial central bore along its longitudinal axis.
Still further in accordance with a preferred embodiment of the present invention, there is provided apparatus for providing a flushing fluid flow through the filter unit including a fluid discharge device arranged for axial movement along the bore.
Additionally in accordance with a preferred embodiment of the present invention, flushing chambers are defined between the line portions.
Further in accordance with a preferred embodiment of the present invention, there is provided a plurality of axial connecting elements which traverse the stack of filter units at locations intermediate inner and outer diameters of the stack of filter units.
Still further in accordance with a preferred embodiment of the present invention, there is provided a manifold defining the inlet and the outlet in communication with the bottom of the housing.
According to a further preferred embodiment of the present invention, there is provided a filter comprising a housing having an aperture at the bottom thereof, a filtering assembly disposed in the housing, and a manifold defining an inlet and an outlet in communication with the aperture.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
FIG. 1 is a partially cut-away side view sectional illustration of a filter constructed and operative in accordance with a preferred embodiment of the present invention;
FIG. 2 is a sectional illustration taken along the lines II--II of FIG. 1;
FIG. 3 is a sectional illustration corresponding to that of FIG. 2 but illustrating a dual nozzle variety of filter otherwise similar to the single-nozzle variety shown in FIGS. 1 and 2;
FIG. 4 is a pictorial illustration of the curved configuration of one of the stack of filter elements shown in FIG. 1;
FIG. 5 is a pictorial illustration of a portion of a stack of filter elements of the type shown in FIG. 4;
FIG. 6 is an enlarged illustration of a portion of the stack of filter elements illustrated in FIG. 5;
FIG. 7 is an enlarged illustration of a portion of the stack of filter elements illustrated in FIG. 5, also showing filter cake and/or sediment associated therewith;
FIG. 8 is an illustration of part of the stack of filter elements illustrated in FIG. 5, illustrating the channels between finger elements thereof;
FIGS. 9A and 9B correspond to FIG. 8 and illustrate the part of the stack of filter elements with filter aid material in associated therewith and with the filter aid material having fallen therefrom respectively;
FIG. 10 is a partially cut-away side view sectional illustration of a filter constructed and operative in accordance with a preferred embodiment of the present invention and arranged to define a drain outlet which is spaced from the bottom of the upstream side of the housing;
FIG. 11 is a partially cut-way side view sectional illustration of a filter constructed and operative in accordance with another preferred embodiment of the present invention, arranged to define a drain outlet which is spaced from the bottom of the upstream side of the housing and to include filter stack supports which traverse the filter disks intermediate the upstream and downstream surfaces of the filter disks;
FIG. 12 is a planar view illustration of a filter disk constructed and operative in accordance with a preferred embodiment of the invention for use in the apparatus of FIG. 11;
FIGS. 13A and 13B are first and second illustrations showing, in exaggerated form, the bendability of the fingers defined by the filter disk of FIG. 12 under respective filtration and backflowing conditions;
FIG. 14 is a pictorial illustration of a portion of a filter stack including filter disks of the type illustrated in FIG. 2, and illustrating, in exaggerated form, the disengagement of filter aid material from the filter stack as the fingers snap back upon termination of the application of a pressure gradient thereacross;
FIGS. 15A and 15B are enlarged sectional views of a portion of the filter stack of FIG. 14 respectively during filtration and during regeneration or backflowing;
FIG. 16 is a partially cut-way side view sectional illustration of a filter constructed and operative in accordance with yet another preferred embodiment of the present invention, arranged to define a central drain outlet and fluid inlet manifold and to include filter stack supports which traverse the filter disks intermediate the upstream and downstream surfaces of the filter disks;
FIG. 17 is an enlarged illustration of the central drain outlet and fluid inlet manifold of FIG. 16;
FIG. 18 is a sectional illustration taken along the lines XVIII--XVIII of FIG. 17; and
FIG. 19 is a sectional illustration of an alternative embodiment of central drain outlet and fluid inlet manifold constructed and operative in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference is now made to FIGS. 1, 2 and 3 which illustrate a filter constructed and operative in accordance with a preferred embodiment of the present invention and comprising a base 70 on which is fixedly supported a bottom housing portion 72. Removably mounted onto the bottom housing portion 72 is a top housing portion 74, which is maintained in sealing engagement therewith by means of a sealing ring 76.
A fluid inlet 78 is provided adjacent the bottom of housing portion 72 and communicates with the outside cylindrical surface, hereinafter termed the "upstream surface", of a stack of filter elements 79. A fluid outlet assembly 80 is coupled to housing portion 72 and communications with a hollow interior portion 81 of stack of filter elements 79 adjacent the inner cylindrical surface of the stack of filter elements, hereinafter termed the "downstream surface".
The stack of filter elements 79 preferably comprises a stack of hollow center filter disks 82 of the type illustrated in FIGS. 4-9B and 12-15B.
The stack of filter elements 79 is preferably removably mounted in coaxial relationship so as define volume 81 and is retained in suitably tight engagement by means of top and bottom retaining collars 84 and 86 joined by a plurality of threaded rods 88, typically four in number, and associated nuts 90. A retaining member 89 supports top retaining collar 84 and is sealingly mounted onto the top housing portion 74 by a threaded retaining ring 91. A collar member 92 engages retaining member 89. As seen in FIG. 2, each of the filter elements 82 is preferably formed with four locating protrusions 85, each formed to permit engagement with a rod 88. Thus it may be appreciated that rods 88 serve to maintain the filter elements 82 in precise azimuthal registration.
A focussed jet nozzle assembly 100 is disposed mainly within volume 81 and comprises a water supply shaft 110 having a water inlet 112 and an associated inlet valve 114.
A rotatable focussed jet outlet head 116 is arranged for relatively free rotation about a rotation axis 118 defined in shaft 110 and is provided with a single output aperture 119. Referring now to FIG. 2, it is seen that the outlet aperture is arranged to provide an eccentric water outlet jet which drives the outlet aperture 119 in rotary motion about axis 118, thus sequentially directing the output jet into each of the azimuthally separated backflow chambers 121 defined by the adjacent filter disks 82.
According to a preferred embodiment of the invention, there is provided above outlet aperture 119 a positioning ring 120, curved to correspond to the curvature of the inner, downstream, surface 122 of the stack of filter elements, for desired positioning of the focussed jet nozzle assembly 100 in volume 81, whereby the axis of rotation of the focussed jet outlet head 116 is centered with respect to cylindrical downstream surface 122, such that the output aperture 119 is always at a predetermined distance from the downstream surface 122, so as not to interfere with the rotation of focussed jet outlet head 116.
It may be appreciated that the focussed water jet exiting from outlet aperture 119 is forced into the individual volumes defined by the stack of filter elements facing the outlet aperture, providing efficient flushing of the accumulated solid material collected therein, and is not permitted to be spread out, which would result in a reduction of its strength and its backflowing efficiency.
The outlet aperture 119 is displaced up and down and rotated about axis 118, and the pressurized stream produced thereby is sequentially concentrated on individual filtering chambers 121 defined in the stack of filter elements to provide enhanced backflowing thereof.
As noted above, outlet aperture 119 is arranged to provide a radially directed concentrated backflowing jet, which serves to flush particulate matter from the stack of filter elements 79.
Inlet 112 is typically coupled via a flexible hose (not shown) to a backflow liquid supply which may be connected to a pressurized source of liquid to be filtered 123 which communicates with the inlet 78 via a two way valve 125. Alternatively the inlet 112 may be coupled to another source of high pressure fluid. Valve 125 selectably couples the water inlet 78 of the filter either to a pressurized water source or to a backflow liquid drain 127.
During normal operation of the filter of the present invention, focussed jet nozzle assembly 100 is located partly within volume 81 and shaft 110 is sealingly coupled to the top portion 74 of the housing by means of sealing collar 92 which sealingly engages threading on retaining member 89. Valve 125 is oriented as shown in FIG. 1 such that liquid to be filtered enters from the pressurized source and passes to inlet 78 and through the stack of filter elements 79 from the upstream surface to the downstream surface, being filtered to the process. The filtered liquid passes through volume 81. Valve 114 is closed.
During backflow operation, valve 125 is manipulated to close off the pressurized liquid source and to provide communication between inlet 78 and backflow drain 127. Valve 114 is opened to provide a pressurized flow of water to focussed jet nozzle assembly 100 and collar 92 is disconnected.
Focussed jet outlet head 116 is manually reciprocated axially along the interior of the stack of filter elements at the downstream surface and is rotated by the fluid stream eccentrically exiting therefrom through at least 360 degrees, causing a high pressure concentrated jet of water to enter the backflow chambers 121 from the downstream surface of the filter for dislodging accumulated filtered material from the upstream side of the stack of filter elements. This arrangement enables substantially all of the backflow chambers 121 to be thus scanned, region by region, by the concentrated jet for efficient backflow cleaning of the stack of filter elements.
Reference is now made to FIG. 3, which illustrates an alternative embodiment of the apparatus of FIG. 1, wherein a focussed jet outlet head 132 having two nearly but not exactly oppositely directed eccentric outlet apertures 134 and 136 is provided. According to a preferred embodiment, the two apertures 134 and 136 are arranged at different axial locations with respect to axis 118, thus providing nearly simultaneous flushing of chambers at two different axial locations along axis 118.
Reference is now made to FIGS. 4-9B, which illustrate a preferred embodiment of filter element constructed and operative in accordance with a preferred embodiment of the invention. The filter element is appropriate for use in any suitable filter apparatus, and is particularly useful in the filter apparatus described hereinabove.
FIG. 4 illustrates in plan view a portion of a filter disk 420 comprising a plurality of finger elements 422. It is seen that the configuration of the finger element 422 is preferably not exactly radial. Specifically, the outline of each finger element is curved along a portion of an arc. Each raised line portion 424 is configured as part of an arc about a different center, as illustrated in FIG. 4, for an exemplary embodiment.
According to a preferred embodiment of the invention, the line portion 424 is formed with a pointed end 425 adjacent the downstream side, thereby to minimize deflection of backflow streams impinging thereon.
The resulting configuration provides a relatively enhanced length of the line portion, and thus of the filter barrier per unit area of the filter element. It will be appreciated that the filter barrier defined by the raised line portion 424 defines a barrier between an upstream side of the filter, here typically the radially outward side of the line portion, and the downstream side of the filter, typically the radially inward side of the line portion. Accordingly, it may be understood that an increase in the length of the filter barrier per unit area of filter element provides a corresponding increase in the filtering capacity of the unit per unit area of filter element, and per unit volume of a filter assembly made up of a stack of such filter elements. The raised line portion 424 is formed with an array of grooves 423.
The spaces 426 between adjacent finger elements 422, which typically lie at the upstream side of the filter, define filtering volumes, which accomodate, according to a preferred embodiment of the invention, a filter cake.
At spaces 428, defined interiorly of each finger element 422, which typically lie at the downstream side of the filter, there are defined planar dividers 429, which are recessed with respect to both the line portions of the first and second surfaces, such that when a plurality of filter elements is arranged in registration in a stack, the planar dividers define a multiplicity of backflow chambers 430 for enhanced and concentrated backflowing. There backflow chambers are particularly suitable for pressurized backflow cleaning by the backflow focussed jet produced by the apparatus of FIGS. 1-3 described hereinabove.
It is a particular feature of the invention embodiment in FIG. 4 that on the downstream side there are defined backflow chambers which concentrate the backflowing effect of a backflowing jet of pressurized fluid, while at the same time, at the upstream side, particulate matter dislodged from the filtering barrier is free to fall out of engagement with the filter stack.
Reference is now made to FIGS. 5-9B. The assembly shown in these figures comprises a stack of identical filter elements 510 being of the type illustrated in FIG. 4 and being formed of a plastic material, such as polypropylene. The filter elements comprise identically patterned opposite first and second planar surfaces. Except for grooves 423, the two planar surfaces of each filter element are mirror images of one another, such that the line portions thereof on both first and second surfaces thereof are in registration, as are the spaces between fingers and inside fingers. The grooves 423 on the facing raised line portions are preferably skewed with respect to one another.
Each planar surface of filter element 510 is formed with a filter barrier defined by a raised line pattern 520, which preferably is arranged to extend continuously in generally undulating configuration, defining a plurality of finger elements 522. The raised line pattern 520 typically defines the outline of each finger element 522 and may be configured to define a smooth outline or alternatively a notched or serrated pattern along the generally radially extending portion of each finger element 522.
As noted in connection with finger element 422 described hereinabove, the outline of each finger element is preferably curved along a portion of an arc. Each raised line portion is preferably configured as part of an arc about a different center, as illustrated in FIG. 4.
The resulting configuration provides a relatively enhanced length of the line portion, and thus of the filter barrier per unit area of the filter element. It will be appreciated that the filter barrier defined by the raised line portion 520 defines a barrier between an upstream side of the filter, here typically the radially outward side of the line portion, and the downstream side of the filter, typically the radially inward side of the line portion. Accordingly, it may be understood that an increase in the length of the filter barrier per unit area of filter element provides a corresponding increase in the filtering capacity of the unit per unit area of filter element, and per unit volume of a stack of such filter elements.
It is a particular feature of the present invention that the upstream side of the filtering barrier defined by raised line portion 520 is a relatively open volume, thus providing enhanced capacity for large particles during filtration and ease of particle disengagement during regeneration and backflowing, while at the same time providing efficient filtration of small particles.
In the embodiment of FIGS. 5-9B, the filter elements making up the stack of filter elements are maintained in precise azimuthal alignment, as by means of one or more azimuthal aligning protrusions 85 associated with each stack of filter elements and registered by a rod (not shown) passing therethrough. Accordingly, when the first and second planar surfaces are arranged in juxtaposed engagement, the finger elements 522 on the facing first and second planar surfaces of adjacent filter elements are in precise registration, defining a filter barrier between the upstream side of the filter and the downstream side. At the locations where the finger elements on first and second surfaces meet in touching engagement, grooves 525 on either or preferably both planar surfaces are engaged. Understanding of this engagement may be assisted by a consideration of FIG. 6, which is an enlargement taken along the lines VI--VI in FIG. 5.
It is a particular feature of the present invention that where grooves are formed on both facing line portions, such grooves 526 and 528 on the opposite engaging surfaces are mutually skewed, as illustrated in FIG. 6, such that they define multiply intersecting paths for fluid flow therethrough, there being defined at intervals along the pathway a particle size gauge being the cross section of the single groove.
This configuration has a number of advantages, including the fact that along much of the pathway from the upstream side to the downstream side across the engaged first and second surfaces, the pathway is larger than the particle size gauge due to the effective combination of grooves formed on the opposite facing surfaces. The multiple interconnections between grooves provides multiple alternative paths for fluid, such that fluid flow may continue notwithstanding blockage of certain passageways. The relatively long and intricate pathway of the fluid provides enhanced depth of filtering, thus increasing filtering efficiency.
Reference is now made to FIG. 7, which corresponds to FIG. 6 but also shows the presence of filter cake and/or sediment during operation of the filter. The illustration shows an embodiment wherein the upstream side is radially outward of the raised line portion 520 and thus intermediate finger elements 522 while the downstream side is at the radially inward side of the raised line portion 520 and thus communicates with the area and volume interior of each finger element 522.
It is seen that fluid, such as water, carrying particulate matter, enters from the upstream side, as indicated by arrows 530, and deposits the particulate matter 532 upstream of the raised line portion 520.
It may additionally be appreciated that a filter aid such as diatomaceous earth, activated carbon or a filter cake may be employed and disposed at the upstream side of the stack of filter elements, as illustrated.
It is a particular feature of the present invention that the spaces between adjacent fingers 522 are open, such that when a plurality of filter disks 510 are stacked with the fingers 522 in registration, channels 560 are defined between adjacent fingers, as seen in FIGS. 8-9B. These channels have particular importance when a filter aid, such as a filter cake, is employed, as the filter cake may be located on the upstream surface of the filter disks 510 along the periphery of the fingers 522.
Assuming that the stack of filter disks 510 is arranged generally vertically, it may be understood that when flow of fluid through the filter from the upstream side to the downstream side is terminated, the filter aid and accumulated filtered out particulate material, which during filtering is stuck onto the peripheral edges 524 of the fingers, as seen figuratively in FIG. 9A, tends to fall through the channels 560 to the bottom of the filter housing, as seen figuratively in FIG. 9B.
Reference is now made to FIG. 10, which illustrates an alternative embodiment of filter, which is identical to that illustrated in FIG. 1 with the exception of the location of fluid inlet 78. It is noted that in the embodiment of FIG. 1, the inlet 78 also functions as a backflow drain and lies somewhat spaced from the bottom of the housing 72. In FIG. 10, the location of the inlet 78 in spaced relationship with the bottom of the housing 72 is emphasized. It will be appreciated by persons skilled in the art that the arrangement of FIG. 10 may replace that of FIG. 1 in all the embodiments of the invention illustrated in FIGS. 4-9B. FIG. 10 is also illustrative of a broader concept which is not limited to disk filters or to filters having a backflow arrangement.
Upon termination of liquid flow through the filter assembly, the liquid drains to the bottom of the housing, and the particulate matter, including filter aid material and solid particles separated from the liquid, falls into the liquid, the filter aid material falling to the bottom of the housing and the solid particles floating in or on the liquid, such that at least some of the filter aid material is retained in the housing while the solid particles are flushed out the drain.
Upon resumption of pressurized liquid flow through the filter assembly, the filter aid becomes distributed on the upstream side of the filter assembly and carries out its normal function, having thus being cleaned, reoriented end recycled.
The drain may be separate from the inlet or identical therewith. In the latter case, the filter apparatus preferably comprises a manually operable multi-flow valve 125 having a normal position wherein liquid to be filtered is coupled to the upstream side of the filter assembly and a backflow position wherein liquid to be filtered is prevented from reaching the upstream side and wherein the drain communicating with the upstream side is coupled for draining to the atmosphere.
Reference is now made to FIG. 11, which illustrates an alternative embodiment of filter, which is generally identical to that illustrated in FIG. 10 with the exception of the locations of rods 88. In the embodiment of FIG. 11, the rods 88, which tightly secure the filter disks 82 together in stack 79, are disposed intermediate the inner and outer diameters of the stack. This arrangement of rods 88 eliminates interference with backflowing which would occur were the rods 88 located inwardly of the downstream surface of the stack 79 and also eliminates the waste of volume in the housing which would result were the rods 88 to be located outwardly of the upstream surface, as shown in the embodiment of FIG. 10. Thus, the embodiment of FIG. 11 maximizes the relationship between stack diameter and inner diameter of the housing.
The embodiment of FIG. 11 is characterized in that it includes a stack of filter elements 79, or any other suitable filter assembly, which is configured to permit particulate matter to fall out of engagement with the upstream side thereof to the bottom of the housing in the absence of liquid flow through the filter assembly. It is appreciated that the foregoing is also true for the embodiments of FIG. 1-9B.
Reference is now made to FIG. 12, which illustrates a filter disk 600 constructed and operative in accordance with a preferred embodiment of the present invention. Filter disk 600 is generally identical to that illustrated in FIGS. 5-8 hereinabove, with the exceptions described hereinbelow:
Filter disk 600 is formed with a plurality of finger elements 602 having a non-radical configuration curved along a portion of an arc. Each finger may be seen to include a line portion 604, which corresponds generally to line portion 424, described above in connection with FIG. 4. The line portion 604 for each finger may be considered to include an outwardly facing portion 606 and an inwardly facing portion 608, joined by an outward curved portion 610 and an inward curved portion 612.
According to a preferred embodiment of the present invention, the outwardly facing portion 606 is longer than the inwardly facing portion 608, such that application of a positive pressure gradient from the upstream side of the stack, here the outside thereof, to the downstream side of the stack, here the inside thereof, as during normal filtering operation, causes inward bending of the fingers 602 in a clockwise sense for the configuration as illustrated in FIG. 12. Removal of the pressure gradient, as upon termination of the supply of pressurized fluid to be filtered, allows fingers 602 to snap back to their original positions.
Further in accordance with a preferred embodiment of the invention there exists a very small difference in thickness of the filter element between its radially inward portion and its extreme radially outward portions, whereby the thickness of the radially outward portions is very slightly less than that of the radially inward portion. This difference in thickness permits the finger elements 522 of adjacent filter elements to be slightly spread apart in a direction parallel to axis 118 (FIG. 1) in response to the application of a backflow jet to the volume interior of each finger element. This spreading apart assists in the disengagement of particles accumulating from the stacked filter elements but is not sufficient to permit entry of small particles into the filter stack during normal filtering flow from the upstream side to the downstream side.
Additionally in accordance with a preferred embodiment of the present invention, adjacent each of the inward curved portions 612 there is provided a narrow, radially extending structural member 614, which extends nearly but not completely to the inner edge of the disk 600. Structural members 614 provide necessary structural support for the disks 600 while also functioning to define backflow chambers 616 between adjacent member 614. These backflow chambers 616 are relatively broad adjacent the downstream side of the stack for minimum interference with a jet of backflow fluid and then narrow as they extend between respective outwardly facing and inwardly facing line portions 606 and 608.
Additionally in accordance with a preferred embodiment of the present invention, and as noted above in connection with FIG. 11, accomodation is made for transversely extending rods 88, in the form of sockets 618 which are located intermediate the inner and outer diameters of the disk 600. According to a preferred embodiment of the invention, as illustrated in FIG. 12, the socket 618 is located in communication with the upstream side of the disk 600 and is arranged as an enlargement of inward curved portion 612, so as to minimize interference with backflowing while minimizing the loss of filter surface area at the socket.
Reference is now made to FIGS. 13A and 13B which illustrate the bending and snap back action of the fingers 602 in accordance with the present invention. In FIG. 13A, the normal orientation of fingers 602, i.e. in the absence of an applied pressure gradient, is illustrated in solid lines, while the bent position thereof, shown in exaggerated form for the purpose of illustration only, is illustrated in broken lines. In fact the angular displacement of the outer ends of the fingers is quite small and is a function of the materials used for the filter elements and of the operating pressure in the filter. In FIG. 13B, opposite bending upon backflowing is illustrated, with the normal orientation of fingers 602 being shown in solid lines and the angular displacement of the outer ends of the fingers during backflowing being shown in broken lines.
It is a particular feature of the present invention that the bending of the fingers, which occurs upon termination of normal filtering and also typically upon the onset of backflowing at a given region, serves to enhance disengagement of particles from the surface of the filter disks 600.
Backflowing, which normally will not occur each time there is a termination of normal filtering, is typically accompanied by additional bending in an opposite sense from the bending produced under normal filtration operation, and thus produces enhanced disengagement of the filter aid material from the stack.
It is also noted that upon backflowing, the fingers of adjacent disks are slightly separated from each other, thus enabling the space between the grooves 526 and 528 to be locally and temporarily enlarged for enhanced backflowing.
FIG. 14 illustrates pictorially the disengagement of filter aid material from a stack of filter disks when the fingers 602 snap back from their bent positions (shown in broken lines) to their normal positions (shown in solid lines).
FIGS. 15A and 15B are enlarged sectional illustrations of this phenomenon, showing the buildup of dirt and accumulation of filter aid material prior to disengagement (FIG. 15A) and following disengagement (FIG. 15B).
It will be appreciated that the filter assembly may comprise any suitable filtering element or assembly of elements although a stack of filter disks as described hereinabove is preferred. A backflowing arrangement as described hereinabove is useful in association with the filter aid retaining arrangement described hereinabove but is not required.
Reference is now made to FIGS. 16-19, which illustrate an alternative embodiment of the present invention wherein a central inlet and outlet manifold is provided. The embodiment of FIG. 16 is generally identical to that shown in FIG. 11 with the following exception:
Disposed at the very bottom of the housing 72 is an inlet and outlet manifold 702 which is coupled to a fluid inlet/backflow drain conduit 704 and to a filtered fluid outlet conduit 706. Fluid inlet/backflow drain conduit 704 is typically connected to a three position valve such as valve 125 shown in FIG. 11.
Fluid communication from a source of pressurized fluid via valve 125 (not shown) to the upstream surface of the filter assembly is illustrated by arrows 708. Fluid communication from the upstream side of the filter assembly to the backflow outlet is illustrated by arrows 710. Fluid communication from the downstream side of the filter assembly to filtered fluid outlet conduit 706 is illustrated by arrows 712.
According to one embodiment of the invention, the manifold is provided with radially extending outlets, as shown in FIG. 18. According to an alternative embodiment of the invention, the outlets may be arranged as illustrated in FIG. 19 to provide a tangent flow. In FIG. 19, this tangent flow of fluid to be filtered into the housing is illustrated by arrows 714.
Referring now to FIGS. 16-19, the structure of the manifold 702 will now be described. The manifold comprises a body member 721 which is connected to conduit 704 and which defines an annular inlet passage 722, communicating with conduit 704. Body member 721 also defines a central outlet passage 724 which communicates with outlet conduit 706.
A collar member 728 threadably engages corresponding threading on the body member 721 and is operative to secure the manifold in sealing engagement with an aperture 730 formed at the bottom of housing 72, by means of a sealing ring 732.
As seen in FIG. 17 and FIGS. 18 or 19, the collar member 728 comprises a plurality of upstanding members 734 which define shoulders 736 which seat on the bottom of the housing 72 at the periphery of aperture 730. Defined between adjacent upstanding members 734 are inlet passages 738.
It is a particular feature of the manifold arrangement shown in FIGS. 17-19 that both inlet and outlet to the filter are provided through a single aperture in the housing 72.
It is a further particular feature of the present invention that should 736 provides centering of the entire manifold assembly onto the housing 72. It is noted that shoulder 736 comprises a surface 740 which lies in a plane parallel to axis 118 which provides the desired centering.
Shoulder 736 also comprises a surface 742 which lies in a plane perpendicular to axis 118 and which lies over the edge of housing 72 adjacent to aperture 730, thereby pressing housing 72 against sealing ring 732 for providing desired sealing upon tight threaded engagement of the collar member 728 onto the body member 721.
It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the invention is defined only by the claims which follow: | A disk-type filter comprising a housing having an inlet connectable to an upstream pipe and an outlet connectable to a downstream pipe, and a stack of filter units disposed within said housing for separating solid particles from a fluid flowing between filter units in said stack of filter units from an upstream side of said stack of filter units to a downstream side thereof, characterized in that said stack of filter units includes a plurality of co-operating filter units defining a plurality of paired co-operating filter surfaces, including first and second surfaces each defining a plurality of fingers, said fingers defined by said first surface being arranged in registration with said fingers defined by said second surface, the exteriors of said fingers defined by said first and second surfaces communicating with either one of an upstream side and a downstream side and the interiors of said fingers defined by said first and second surfaces communicating with the other one of said upstream side or downstream side, spaces being defined in association with said fingers defined by said first and second surfaces and being disposed in registration so as to define channels, which permit particulate matter to become disengaged with said upstream side of said fingers defined by said first and second surfaces. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a National Stage of International Application No. PCT/GB2007/001581 filed May 1, 2007, the disclosures of which are incorporated herein by reference in entirety, and which claimed priority to Great Britain Patent Application No. 0700052.4 filed Jan. 3, 2007 and Great Britain Patent Application No. 0608577.3 filed May 2, 2006, the disclosures of which are incorporated herein by reference in entirety.
BACKGROUND OF THE INVENTION
This invention relates to improvements in gear assemblies and in particular to gear assemblies for use in electric power assisted steering systems of the kind which incorporate a worm and wheel gear assembly for transferring torque from an electric motor to a steering shaft or output shaft operatively connected thereto.
It is known to provide a power steering system for a vehicle comprising an electric motor having a stator and a rotor, an input shaft operatively connected to the rotor and adapted to rotate therewith, an output shaft associated with a steering shaft, and a gearbox adapted to transfer torque from the input shaft to the output shaft in response to a measure of the torque in the output shaft as produced by a torque sensor. The motor is typically operated to apply an increasing torque to the output shaft as the measured torque increases, thus applying assistance which helps reduce the effort needed to steer the vehicle.
In a simple arrangement the input shaft carries a worm gear, and the output shaft carries a wheel gear. The teeth of the worm and wheel intermesh to transfer the torque. This system is simple and robust whilst providing relatively high gearing with a low component count. There exists, however, a problem in such gearboxes with noise and vibration due to incorrect meshing between the worm and wheel. This may arise due to manufacturing tolerances, thermal changes in dimensions or distortion due to torsional loads and wear during service.
BRIEF SUMMARY OF THE INVENTION
According to a first aspect the invention provides a gearbox assembly for use in an electric power assisted steering system comprising: a housing; an input shaft located at least partially within the housing which carries a worm gear and includes means for coupling to a motor rotor at one end; an output shaft located at least partially within the housing which carries a wheel gear; a first bearing means which supports the input shaft at a side of the worm distal from the end of the shaft which connects to the motor rotor and second bearing means which supports the input shaft at the other side of the worm; and a (first) resilient biasing means adapted to apply an axial load to the input shaft, the resilient biasing means acting upon a part of the first bearing means.
The application of the axial load biases the axial clearance in the second bearing means by which we mean that an axial pre-load is applied to the second bearing which holds the bearing races in place axially and resists any load in the input shaft due to engagement of the worm and wheel which may otherwise cause the second bearing races to move axially relative to one another. The axial clearance in the second bearing is a source of unwanted rattle noise. The contact forces on the teeth of the worm shaft apply an axial load to the input shaft, the direction of which reverses with the direction of rotation of the gear wheel. The application of the axial pre-load from the first biasing means inhibits the axial movement of the second bearing inner race to outer race and hence reduces rattle from the second bearing.
The first biasing means may apply to an axial load greater than the maximum expected axial reaction force that can be created by the flanks of the worm wheel acting on the worm gear.
There may further be an additional (second) biasing means adapted to apply a radial load to the input shaft which may also act upon the first bearing means. The additional biasing means may act between the housing and the first bearing means. It may comprise a leaf spring which is connected to the housing at one end and acts upon the first bearing means, perhaps the outer race, at its other end.
The second biasing means may therefore act to bias the input shaft in a tilting movement (i.e. generally radially with respect to the axis of the shaft), the tilting movement being centred about the second bearing means.
In order to permit the first bearing means to move relative to the housing when subjected to such a tilting load, the second bearing means may be adapted to permit a degree of tilt of the input shaft within the bearing relative to the housing. This tilting bearing is preferably the one closest to the motor to minimise misalignment between motor rotor and input shaft for a given amount of tilt. The bearing may allow an angle of tilt of up +/−0.1 degrees or higher, say up to +/−0.2 degrees or thereabouts.
The first bearing may be so constructed and arranged as to support the worm shaft by resisting only radial loads and not axial loads (over a limited range around a centre point of course), whilst the second bearing may be so constructed and arranged as to resist both axial and radial loads. In each case, the loads will be applied by the movement of the input shaft.
Most preferably, the bearings may be arranged so the input shaft has freedom to articulate in one plane about the second bearing. The orientation of this plane is such that input shaft has freedom to move in and out of mesh with the gearwheel.
The input shaft worm may be biased into mesh with the gearwheel under the load from an additional biasing means which is in the form of a resilient spring such as a leaf spring that may act between the housing and, most preferably, the first bearing.
Where such a leaf spring is provided, the application of the force from the leaf spring forces the worm into mesh with gear wheel removing lash and hence rattle between the flanks of the two sets of gear teeth.
To achieve the desired articulation the first bearing may have freedom to translate relative to the gearbox housing in the said plane. Also the second bearing may have sufficiently large clearances to allow the articulation.
The first resilient biasing means may rotate with the first shaft in which case it acts between the motor rotor and the first shaft.
Alternatively it may be rotationally static in the gearbox housing in which case it acts between the gearbox housing and the outer race of either the first or second bearings.
The first resilient biasing means may apply an axial load to the input shaft in a direction away from the motor. It may do so by applying a tensile or a compressive force, e.g. it may pull the input shaft or push it. In each case, it may act upon the first bearing means. It may be located at the end of the input shaft furthest from the motor.
The resilient biasing means may comprise a part of the first bearing means acting upon a reaction face provided on the input shaft or otherwise being fixed to the input shaft. It may be arranged to pull the input shaft towards the housing or to push it towards the housing. This is convenient as it allows easy assembly and can be retrofitted in some cases by replacing the first bearing means.
Alternatively, it may act between any two parts of the first bearing means, which are fixed relative to the input shaft and housing respectively. In a still further alternative, it may act between the housing and a part of the first bearing means.
The resilient biasing means may comprise a tensile element, for example a tension spring, such as a coil spring or a leaf spring. The spring may be attached to a part of the input shaft via the first bearing at one end or some other element fixed axially relative to the input shaft. It may be fixed to the housing at its other end, or some part that is fixed axially relative to the housing. It could, for example, be attached at each end to different parts of the first bearing assembly.
The resilient biasing means may alternatively be a compressive element such as an elastomeric element or other compressible material. This may comprise a collar of compressible material that acts between a first reaction face fixed relative to the input shaft and a second reaction face fixed relative to the housing. The first reaction face may comprise a part of the first bearing means, for example the outer bearing race, which is fixed axially to the input shaft, the second reaction face comprising a different part of the first bearing means fixed relative to the housing, or even a part of the housing itself.
In a preferred arrangement the second reaction face may comprise a casing of a cartridge that is inserted into the housing. The cartridge casing may house the first bearing means.
An additional linear thrust bearing may be provided between the resilient biasing means and the first reaction face and/or the second reaction face that enables the first bearing means to slide relative to the housing despite the presence of the force applied by the resilient biasing means. The reaction face, thrust bearing and first bearing means may all be provided in a cartridge that can be fixed to the gearbox housing.
The first bearing means may comprise a main bearing assembly fixed axially relative to the input shaft by an end nut screwed onto the input shaft or may be a press fit. It may be located between a first reaction face defined by the end nut threaded onto the end of the input shaft. It could of course be located in position in other ways. The bearing means further includes a bearing cap that provides a second reaction face for the main bearing assembly and locates the bearing race. This second reaction face is provided on the side of the main bearing assembly nearest the worm gear.
A tension tube may be provided which at least partially surrounds the main bearing race and supports at one end the bearing cap, the tension tube extending away from the worm towards the end of the input shaft and defining at its other end a third reaction face upon which the resilient biasing means acts.
In this arrangement, the resilient biasing means comprises a compression spring such as an elastomer spring or rubber block. This acts in compression to push the tension tube away from the worm, in turn pulling on the bearing cap to press the main bearing against the first reaction face and thereby pull the input shaft in a direction away from the end that couples to the motor so as to bias the second bearing and provide an axial pre-load.
The bearing means may additionally include a further bearing assembly comprising a fixed race secured to the gearbox housing and a moving race that is free to move relative to the fixed housing by rolling elements such as balls located between the fixed and moving races to define a thrust bearing, the moving race providing a reaction face for the biasing means, and in which the moving race can move in a direction radial to the axis of the input shaft whilst preventing translation of the moving race orthogonal to the plane of articulation.
The assembly may be so constructed and arranged that the action of tightening the end nut on the input shaft to clamp the first bearing to the shaft applies a preload to the biasing means by compressing the elastomer spring.
In an alternative, instead of providing a biasing means between the end of the tension tube and a third reaction face fixed to the housing that works in compression, a tension spring can be secured at one end to the tension tube. This may be operatively secured at its other end to a part of the gearbox housing or a support bracket fixed to the housing. A hook may be provided at each end of the spring. One hook may engage a hole in the tension tube and the other may hook around a part of the support bracket that is fixed to the housing.
The support bracket may comprise a frame which is a sliding fit within a support collar that is arranged to fit within a complimentary recess in a part of the housing which accommodates the end of the input shaft carrying the first bearing means. A means for adjusting the position of the frame within the collar, effectively drawing the frame into or out of the collar in the main housing, may be provided.
The frame may include a bar which extends orthogonal to the axis of the input shaft. The hook of the spring may be secured to this bar.
The locating bar for the spring may be supported at its ends within half round locating grooves provided in the support frame. A cover may be provided which seals the support frame to the support collar when assembled whilst permitting access to the adjustable fastening. The inside of the cover may be provided with further half round grooves which surround the locating bar to prevent it from slipping out of position. The cover may be a snap fit to the frame.
As described, the frame and its cover are located at least partially within the collar. The adjustable fastening may comprise a bolt which engages a captive nut within a deformable block that is located within an elongated groove in the collar such that rotation of the bolt draws the nut and block towards the collar and away from the housing. This deforms the block to clamp the collar in place in the housing.
As will be appreciated, it is envisaged that the biasing means may be provided as an integral part of the first bearing assembly. This has the advantage that it can be installed or removed in one process as part of the installation of the first bearing assembly. It is also easy to access for maintenance by being located at the free end of the input shaft.
The biasing means may be adjustable to permit a degree of control over the amount of load provided. This could be achieved, where applicable, by adjustment of the position on the end of the input shaft.
It is important to ensure that the meshing force applied between the worm and wheel is not too high since it will cause some friction in the gearbox. This can be achieved by providing a biasing means that has a relatively low load, e.g. spring rate. The skilled man will be able to provide such a suitable load for any given system by trial and error if required or by proving an adjustable biasing means. For example, a meshing force of up to 0.5N measured at the gearwheel is probably acceptable for most electric power steering applications.
The input shaft may be provided with means for connection to the rotor of a motor, and an opening may be provided in the housing to permit connection between motor and input shaft to be effected. The input shaft preferably protrudes through the opening, which also serves to locate the second bearing means. Therefore, in a preferred arrangement the first bearing means is provided at the side of the worm farthest from the motor.
A flexible coupling may be provided between the input shaft and any motor rotor attached to it.
Each of the first bearing means and the second bearing means may comprise two bearing elements rotatably coupled by one or more bearings such a needle bearings or ball bearings. The elements may define bearing races which define the path of the bearings.
According to a second aspect the invention provides an electric power assisted steering system comprising a gearbox assembly according to the first aspect of the invention, an electric motor fixed to the housing and to the input shaft of the gearbox assembly, a steering shaft which is operatively coupled to the output shaft of the gearbox, a torque sensor which is adapted to measure the torque in the output shaft, a controller which adapted to produce a motor control signal according to at least the measured torque, and a motor drive circuit which is adapted to apply a drive signal to the motor in response to the control signal.
Other advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, when read in light of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified and cut-away partial representation of a first embodiment of a gearbox assembly in accordance with the present invention;
FIG. 2 is a detailed view of a part of the assembly of FIG. 1 ;
FIG. 3 is an exploded solid view of the component parts of a first bearing means of the assembly shown in FIGS. 1 and 2 ;
FIG. 4 is a cut-away view of a part of a second embodiment of a gearbox assembly in accordance with the present invention;
FIG. 5 is an exploded view in solid of several of the internal parts of the first bearing means which is used in the second embodiment of FIG. 4 ;
FIG. 6 is an alternative view in solid of the parts of FIG. 5 when assembled;
FIG. 7 is an exploded view in solid of a third embodiment of a gearbox assembly including a bearing means and resilient biasing means; and
FIG. 8( a ) is an enlarged exploded view of the cassette of the third embodiment and 8 ( b ) shows the cartridge when assembled prior to insertion to the gearbox housing.
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of a gearbox assembly is shown in FIG. 1 . It comprises a cast metal housing 100 . The housing provides a mating face for a motor which is coupled to a worm gear 110 provided on an input shaft 120 inside the housing. The rotor 130 of the motor can be seen to the left of the Figure. The motor and the housing are secured together by bolts or other fastenings (not shown). The input shaft 120 is supported by two bearing assemblies 140 , 150 —one towards each end, that are located within recesses in the gearbox housing 100 .
A wheel gear 160 is also provided on an output shaft 170 which is also supported by bearings (not shown) on either side of the wheel. Again these bearings are supported in recesses (not shown) in the housing. This output shaft is typically part of a steering shaft which operatively couples a steering wheel to one or more road wheels of a vehicle. The shaft in the Figure extends out of the paper towards the reader.
The teeth of the wheel gear 160 and the worm gear 120 are complementary and intermesh with one another such that rotation of the worm gear 120 by the motor causes the wheel gear 160 to rotate at a lower rate. In this manner rotation produced by the motor is transferred to the steering shaft. By providing for a suitable control for the motor it is possible in this way to provide an assistance torque to the steering to help a driver of the vehicle.
The bearings (not shown) that support the output shaft are substantially fixed relative to the housing to prevent any axial or radial movement of the output shaft carrying the wheel relative to the housing. The bearings 140 , 150 that support the input shaft with the worm gear are arranged to provide a degree of movement to the input shaft, and in particular to bias the worm gear into contact with the wheel gear. This is achieved through applying a radial load to the input shaft 120 towards the wheel gear 160 . In the example a biasing means in the form of a leaf spring 180 is used. This spring 180 is fixed at one end 185 to the outside of the housing 100 and projects through an opening 186 in the housing 100 onto one of the bearing assemblies—referred to hereinafter as the first bearing means. The bearing 150 nearest the motor is hereinafter referred to as the second bearing means.
As well as applying a radial load to the input shaft 120 , the assembly is also designed to apply an axial load to the input shaft to bias the clearance of the second bearing 150 . This axial load is achieved in this embodiment by pushing a part of the first bearing means 140 that is fixed to the input shaft 120 away from the motor.
The first bearing means is shown in more detailed in the enlarged view of FIG. 2 and also the exploded view of FIG. 3 of the accompanying drawings. It comprises a main bearing assembly 141 which is located in a space between a reaction face 142 defined by a step change in diameter of the input shaft and a lock end nut 143 which is threaded onto the end of the input shaft 120 to clamp one race of the main bearing assembly in a fixed axial location on the input shaft.
The other race of the main bearing contacts a bearing cap 144 in the form of an annular ring that surrounds the input shaft 120 on the side of the main bearing nearest the worm 110 . A tension tube 145 is provided and the bearing cap 144 may be integrally formed with an end of the tube nearest the worm gear. As shown, the cap and tube are separate, interconnectable elements. The cap has an annular ridge that projects inwardly from the tube. The tension tube 145 has an internal diameter greater than that portion of the input shaft that it surrounds and that of the lock nut. The tube 145 extends away from the worm towards the end of the input shaft and defines at its other end an outwardly projecting annular ridge 146 that defines a third reaction face facing the worm gear. This third reaction face provides a surface upon which a resilient reaction means acts.
The resilient biasing means comprises a rubber bush or elastomer spring 147 which fits snugly around the outside of the tension tube 145 adjacent the projecting ridge 146 so as to engage the third reaction face at one end. The elastomer spring 147 has a thickness substantially the same as the collar. The end of the spring distal from the ridge contacts a moving bearing race 148 a that surrounds a portion of the tension tube. Notably this moving race is free to slide over the tension tube. Associated with this moving race is a fixed race 148 c that is secured to the housing. The fixed race may be a press fit into a recess in the housing 100 . Ball bearing cages 148 b containing 4 steel balls located between the fixed and moving races, and are located within elongate linear grooves 149 in the two races. These can best be seen in FIG. 3 in which the grooves 149 are clearly visible.
The spacing between the projecting ridge 146 of the tension tube 145 and the moving race 148 a together with the free length of the elastomer spring 147 are chosen such that the bush is in compression when in use. Thus, the moving race acting on the fixed race through the steel balls reacts the compressive load in the elastomer spring. As the spring tries to decompress to its free length, it pushes the tension tube away from the worm, in turn pulling on the bearing cap to press the main bearing against the first reaction face and thereby pull the input shaft in a direction away from the end that couples to the motor and into engagement with the wheel gear.
The steel balls 148 b in between the fixed and moving races 148 c , 148 a constrain the moving race, and hence the main bearing, to move relative to the housing in a direction parallel to the grooves in which the bearings are located. The direction of these grooves is chosen to be parallel to a direction in which the load is applied by the leaf spring 180 . This allows the leaf spring 180 to load up the first bearing means.
Although not shown in the Figures, the second bearing assembly 150 must be able to accommodate this movement of the input shaft by permitting it to articulate about the second bearing under the force applied by the leaf spring 180 .
In an alternative, instead of providing a biasing means between the end of the tension tube and a third reaction face fixed to the housing that works in compression, a tension spring can be secured at one end to the tension tube. This may be operatively secured at its other end to a part of the gearbox housing. A hook may be provided at each end of the spring. One hook may engage a hole in the tension tube and the other may hook around a part of a support member that is fixed to the housing.
An embodiment of a first bearing means of this type is shown in FIGS. 4 to 6 of the accompanying drawings. Where possible, parts in common with the first embodiment have been given the same reference numerals.
As with the first embodiment, the main bearing race 142 is secured to the input shaft 120 between a reaction face defined by the shaft and a locking end nut 143 . A tension tube 145 defining at one end a bearing cap extends beyond the free end of the shaft. This is provided with an opening 145 a onto which is hooked a hook 201 provided at one end of a tension spring 202 . The other end of the spring 202 is also provided with a hook 203 which engages a bar 204 supported by a frame 205 of a support member. This support member is operatively coupled to the main housing 100 to react the tension in the spring.
The support bracket comprises a frame 205 having an annular base and two spaced apart support arms 206 , 207 extending from it which carry the bar 204 . The bar is located within half round grooves in the top of the arms.
The annular base of the frame is a sliding fit within an (optional) support collar 208 that is a press fit within a recess in the main housing 100 . A bolt 209 passing through an opening in the frame engages a nut 210 that is captive within a parallel sided tapered plastic block 211 that is in turn located within a parallel sided elongate slot in the frame or support collar. Tightening the bolt pulls the block between the frame and the housing which secures the frame to the housing.
To control the tension, the bolt locks down onto a spacer which fits over the end nut. This determines how far the collar can be pushed into the housing, which sets the tension in the spring.
On assembly a cap 212 is located over the support frame to seal the assembly and prevent unwanted dirt entering the spring or the main bearing.
As will be appreciated, it is envisaged that the biasing means may be provided as an integral part of the first bearing assembly. This has the advantage that it can be installed or removed in one process as part of the installation of the first bearing assembly, and provides a compact self-contained solution to the problem of providing axial loading.
Many modifications could, of course be made whilst remaining within the teachings of the invention. It is to be understood that the use of a leaf spring to provide the tilting force to the input shaft is not essential to the invention. Other types of spring or means for moving the input shaft could be provided.
A still further alternative is shown in FIG. 7 of the accompanying drawings. Where possible the same reference numerals used for FIG. 1 have been used to denote like parts. In this arrangement a first bearing means 300 is supported relative to the housing in a cassette body 310 . The body 310 is fixed relative to the housing 100 and allows articulation of the input shaft 120 about the second bearing 150 to remove worm to gear clearances as well as providing resilient biasing required to reduce rattle from the second bearing axial clearance. The structure of the cassette 310 can be seen clearly in FIGS. 8( a ) and 8 ( b ) of the accompanying drawings.
As shown in FIG. 7 the cassette body 310 locates in housing, the protrusion 315 on the cassette body engages with a slot 313 in the housing to ensure correct orientation. An inwardly directed annular protrusion 318 at the base of the cassette body 310 defines a reaction face and it has annular side walls that together with the base define a void. The hole in the base inside the protrusion allows the input shaft 120 to pass clear through it. Located in the void is a cap 320 which defines a recess into which an annular spring 330 is located. The spring comprises an elastomeric element. On top of the spring 330 is a first annular race 340 of a linear thrust bearing 345 . This faces a similar race 360 and is separated from it by four steel balls that are located in a cage 350 . The balls run in two parallel grooves 341 , 342 in each race 340 , 360 . The grooves lie in a plane orthogonal to the central axis of the cartridge allowing some radial movement of the moving race 360 relative to the cartridge body 310 . Alignment tabs 317 on the wall of the cartridge body co-operate with openings in the bearing races to ensure the grooves are correctly aligned. Finally on top of the moving race is located the first bearing 140 with a light interference fit on the outer diameter of the first bearing and the internal diameter of the moving race. A shoulder on the outer diameter of the first bearing mates with the end face of the moving race. The three latches in the cassette body axially retain the moving race and first bearing sub assembly. This closes the end of the cartridge. The cartridge can be seen assembled in FIG. 8( b ) of the accompanying drawings.
Prior to assembly all of the parts are stacked loosely in the cartridge body 310 . The input shaft 120 is then passed through the cartridge so it is supported by the first bearing means 140 . This bearing 140 is a press fit onto the shaft, and as it continues to be pressed in place it compresses the spring 330 as the components are squashed towards the reaction face 318 . Eventually the bearing 140 contacts a shoulder 110 on the shaft 120 and so cannot be pressed in any further. This defines the load on the spring 330 .
In use, the cartridge 300 allows the first bearing means 140 to move in the cartridge so the shaft 120 can articulate in one plane in and out of mesh with the gear wheel 160 to take up wear, manufacturing tolerance and dimensional changes with temperature and humidity. The cartridge housing does not move relative to the housing giving a secure location and ensuring the spring load remains relatively constant.
The amount of movement is dictated by the free play between the moving part of the bearing and the wall of the cartridge body.
The compression load in the elastomer spring acts to pull the worm shaft 120 which preloads the second bearing 150 preventing it from generating rattle noise. The compression load also acts to secure the cassette against a shoulder 314 in the housing 100 .
In accordance with the provisions of the patent statutes, the principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope. | In a gearbox for use in an electric power assisted steering system comprises a housing, an input shaft located at least partially within the housing which carries a worm gear and includes means for coupling to a motor rotor at one end, an output shaft located at least partially within the housing which carries a wheel gear, and a first bearing means which supports the input shaft at a side of the worm distal from the end of the shaft which connects to the motor rotor and second bearing means which supports the input shaft at the other side of the worm, the invention comprises further providing a first biasing means adapted to apply an axial load to the input shaft to bias the axial clearance in the second bearing, the second biasing means acting upon a part of the first bearing means; and a second biasing means adapted to apply a radial load to the input shaft to bias the worm into engagement with the wheel gear, the second biasing means also acting upon a part of the first bearing means. | 5 |
The present invention is generally related to RF circuitry and more specifically, to preventing oscillations in high gain RF circuitry through the use of RF energy absorber blocks and even more specifically, to the means for holding said absorber blocks in position while easily allowing re-positioning for optimization.
BACKGROUND
It has been found that high frequency circuits "leak" RF energy. The FCC has required that this leakage be kept below certain standards. Since the FCC made requirements put rules in place aimed to prevent the leakage, radio frequency circuits are typically enclosed in a metal container. When the enclosure cover is off while the circuits are being optimized in their performance, the RF energy escapes to the outside. It has been found that when a cover is placed on the enclosure, and the RF energy can no longer escape to the atmosphere, that it may be reflected to sensitive portions of the circuit in a positive feedback manner, and conversely may cause oscillations or other detrimental effects. Thus, it is important in high gain circuits that some type of RF energy absorption material be used to minimize reflective energy. The use of RF energy absorber blocks adjacent such energy emitting circuitry is one such solution to minimize reflective energy.
When a high gain amplifier capable of passing high frequency radio signals is placed in an enclosed environment, standing waves of other detrimental effects are sometimes initiated such that the amplifier will oscillate. Thus, while the amplitude/frequency response of the circuit may be satisfactory after adjustment of various parameters with the cover of the enclsure off, the amplifier may break into oscillation upon complete enclosure of a circuit by fastening down the cover. RF energy absorber blocks can be positioned adjacent the RF circuitry to minimize adverse results upon encosing the RF circuitry.
In the past, the absorber blocks have been held in place by various means such as a screw-type rod with nuts used to hold the absorber blocks in place against the wall until the optimum placement is determined. Upon proper placement, the absorber blocks are often epoxied or otherwise permanently attached to the walls. If the screw rod is made of metal, as has been the case in the past, and the parts accidentally fall onto the microwave circuit during the positioning process, the adjacent microwave circuitry can be damaged mechanically and/or electrically.
The present invention improves upon the prior art referenced above by making the retainer device out of a low dielectric material such as nylon or delrin. If the metal screw were merely made out of one of these materials, the potential for damage from dropping it would be minimized both electrically and mechanically. However, the screw-type device is still awkward to install and to adjust for block re-positioning purposes.
The present concept uses deformation of a portion of a retaining device to provide sufficient forces between the absorber blocks and the walls to hold these blocks in position long enough to accurately ascertain block position for optimum circuit performance characteristics. Properly positioned blocks can then be epoxied or otherwise adhesively attached to the walls. While the present retaining device could be removed at this time, it is typically left in place for potential future use if the circuit board needs replacing in the field.
It is an object of the present invention to provide an improved absorber block retainer.
Other objects and advantages of the present invention will be apparent from a reading of the specification and appended claims in conjunction with the drawings wherein:
FIG. 1 is a plan view of a prior art solution to retaining absorber blocks;
FIG. 2 is an elevation view of FIG. 1;
FIG. 3 in plan view illustrates an ellipsoid retainer using channels to prevent dislocation between the retainer and an absorber block;
FIG. 4 is an elevation view of FIG. 3;
FIG. 5 in plan view illustrates a retainer in the form of a flexed or bent rod holding absorber blocks on either side of enclosure walls;
FIG. 6 is an elevation view of FIG. 5;
FIG. 7 is a plan view of a rod of spring-type material in the form of a loop holding a single absorber block against one wall of an enclosure;
FIG. 8 is an elevation view of FIG. 7;
FIG. 9 is a plan view of a triangular-shaped retaining device; and
FIG. 10 is a plan view of a substantially rectangular-shaped retaining device.
DETAILED DESCRIPTION
In FIG. 1 walls 10 and 12 of an enclosure are shown in a plan view. This view includes a printed circuit board 14. Absorber blocks 16 and 18 are also shown with a screw-type rod 20 having nuts 22 and 24.
FIG. 2 illustrates an end or elevation view of FIG. 1 with the addition of a dash line cover 26. FIG. 2 that there are components on the surface of board 14. The cover 26 is used to contain RF energy within the enclosure defined by walls 10 and 12. Coverage of the other end of the enclosure is not specifically shown.
FIG. 3 shows walls 30 and 32 along with absorber block 34 and an elliptical ring 36.
FIG. 4 uses the same designations as shown in FIG. 3 with the addition of 38 for the microwave circuit board and 40 for a cover. It will also be noted from the elevation view that the ellipsoid retainer 36 is grooved where flanges 42 and 44 partially enclose absorber block 34. The flanges 42 and 44 fit within grooves 50 and 52 on wall 32 to prevent movement with respect to the wall 32. While the flanges may not be necessary to frictionally hold the retainer 36 and the absorber block 34 in place for initial positioning or re-positioning, they do facilitate maintaining a desired distance from board 38.
In FIG. 5 walls 60 and 62 are shown with absorber block 64 and 66 and a rod 68 of springy-type low dielectric material such as delrin or nylon.
FIG. 6 uses the same designators as FIG. 5 with the addition of a circuit board 70 and a dash line cover 72. It will be noted that there are illustrated openings 74 and 76 in the absorber blocks 64 and 66 respectively, to more readily keep the rod 68 from becoming dislocated while the blocks 64 and 66 are being re-positioned for optimum circuit performance.
In FIG. 7 walls 80 and 82 are illustrated with an absorber block 84 and a retainer 86 in the form of a rod of material which is looped in the form of a hairpin or U-shaped and both ends inserted in a cavity or opening 88 within absorber block 84.
FIG. 8 uses the same designations as in FIG. 7 with the addition of 90 for the printed circuit board and 92 for a dash line cover.
FIG. 9 shows walls 100 and 102 with an absorber block 104 and a triangular-shaped retainer 106. A teat or extension 108 on retainer 106 is positioned within a cavity or opening 110 in absorber block 104.
FIG. 10 shows walls 120 and 122 with absorber blocks 124 and 126 and a retainer generally designated as 128 having side walls 130 and 132 and further walls 134 and 136.
Retainer 36 in FIGS. 3 and 4, retainer 68 in FIGS. 5 and 6, retainer 86 in FIGS. 7 and 8, retainer 106 in FIG. 9, and retainer 128 in FIG. 10 are all made of springy-type low dielectric material such as delrin or nylon.
It will be noted that all embodiments of the inventive concept can be used with one or two absorber blocks, and while relative position holding devices such as teat 108 and flanges 44 and 42 have been used, friction will typically provide all the relative positioning required in most instances. However, the positioning devices have been illustrated as an enhancement that may be used where required or desired.
OPERATION
While it is believed that the operation of the present invention should be obvious from the drawings and previous description, a summary of operation of the Figures will be provided. The prior art approach shown in FIG. 1 was to insert the ends of the screw 20 in the openings within the absorber blocks 16 and 18 and slide the combination or package into place. The nuts 22 and 24 were then rotated to provide forceful contact with the absorber plates or blocks 16 and 18 so as to exert forces on the walls 10 and 12 via the absorber blocks 16 and 18. At least one of the nuts 22 and 24 needed to be loosened to attempt re-positioning of the blocks during the determination of signal bandwidth and amplitude response testing. At times, this could cause the parts to fall either due to slippage of one of the blocks vertically or due to inadequate attention being taken as to whether ends of screw 20 were maintained in the opening of each of the absorber blocks 16 and 18.
As mentioned previously, the flanges 42 and 44 of retainer device 36 in FIGS. 3 and 4 would not be required in all embodiments. Without the existence of the flanges, there would be some possibility of the relative position of absorber block 34 and ellipsoid 36 not being maintained. Further, the absorber block 34 may not be maintained the right distance vertically with respect to board 38. With the flanges 42 and 44 it would be easier to maintain such a distance and would minimize the chances that the absorber block 34 can move and/or fall with respect to the retainer 36. While FIG. 3 and some of the following FIGS. such as 7 and 10 also show only a single absorber block, the concept can easily be used with two absorber blocks in all instances.
FIG. 5 illustrates a rod 68 of springy, substantially RF transparent or low dielectric material which is deformed to a compressed mode as shown when the absorber block 64 and 66 are placed close enough together to fit between walls 60 and 62. The openings 74 and 76 within absorber blocks 64 and 66, respectively, prevent the rod 68 from falling out. However, the friction with some types of materials would be sufficient to prevent slippage and the openings 74 and 76 would not be required in all instances using this embodiment of the concept. The concept of FIG. 5 could be used with a single absorber block by having a plurality of openings in wall 62 or having a slot with sufficiently close tolerances to keep the rod 68 from moving excessively.
The concept shown in FIG. 7 uses a single rod 86 of low dielectric material with one end placed in opening 88 and with the rod bent somewhat as shown so that the other end is also placed in opening 88. This gives a considerable amount of surface contact with wall 80 and thus, easily solves the problem of providing retention for a single absorber block. However, the concept of FIG. 7 can also easily be used with two absorber blocks and further, a protrusion could be provided at the middle point of rod 86 (in a manner similar to that used infra in FIG. 9) to be used as a positioning device with a second block.
The comment with respect to the positioning device of FIG. 7 is more clearly illustrated in FIG. 9 where a positioning extension or teat 108 is used to reduce the possibility of vertical movement of the retainer 106 with respect to absorber block 104. As will be noted, the walls of the triangular retainer device 106 have been flexed from their normal equilateral triangle configuration to a distorted triangle for providing the compressive and frictional forces to hold absorber block 104 in position against wall 102. Again, this concept can be used with either one or two absorber blocks and positioning devices such as 108 could be used within the middle of the opposing base of 106 if used with a second absorber block. Other approaches such as the flanges of FIG. 3 may also readily be used in connection with device 106.
Retainer device 128 in FIG. 10 illustrates that a normally substantially rectangular retainer device would have the walls 130 and 132 flexed upon compression to provide the forces to hold absorber blocks 124 and 126 in place. With the large surface area of sides 134 and 136 contacting absorber blocks 124 and 126, respectively, no positioning devices such as the extension 108 of FIG. 9 should be required. However, such could be utilized if deemed desirable.
While we have illustrated several different configurations of low dielectric retaining devices for practicing the inventive concept, we wish to be limited not to the specific embodiments illustrated, but only by the scope of the appended claims wherein we claim. | A springy, low dielectric retainer device in the form of a rod, a triangle, an ellipse or whatever, is used in a compressed condition to hold RF energy absorber blocks in position juxtaposed "energy leaky" RF circuitry. The absorber blocks are held in position due to frictional forces provided by the compressed retainer. In this manner, the absorber blocks can be re-positioned to obtain optimum amplitude/frequency response characteristics from the affected RF circuit. | 5 |
FIELD OF THE INVENTION
The present invention relates generally to melt-spinning apparatus and methods, and more particularly to a linear flow equalizer for a spin pack of a melt-spinning apparatus and methods of forming non-woven webs with a melt-spinning apparatus incorporating the linear flow equalizer of the invention.
BACKGROUND OF THE INVENTION
Non-woven webs are incorporated into a diversity of consumer and industrial products, including disposable hygienic articles, throwaway protective apparel, fluid filtration media, and household durables. Generally, non-woven webs are formed using melt-spinning technologies, such as spunbonding processes and meltblowing processes, that form continuous filaments or fibers composed of one or more thermoplastic polymers. Spunbond non-woven webs are relatively strong in both the machine and the cross-machine directions because of drawing that aligns the polymer molecules. The continuity of the filaments also contributes to the observed strength of spunbond non-woven webs. Spunbond non-woven webs also resist abrasion, have a high porosity, and may be soft and conformable.
Spunbonding processes generally involve pumping one or more molten thermoplastic polymers through a spin pack that distributes, filters, combines, and finally extrudes continuous filaments of the constituent thermoplastic polymer(s) through hundreds or thousands of spinneret holes or orifices in a spinneret. After extrusion, the filaments are cooled or quenched to increase their viscosity and then drawn or stretched by an impinging high-velocity airflow generally capable of orienting the molecules of each constituent thermoplastic polymer if the air velocity is sufficiently high. The airflow propels the drawn filaments toward a forming zone to form a non-woven web on a moving collector.
The spin pack distributes a flow of each constituent thermoplastic polymer from a few inlet ports to individual outlet ports that span the width of the spin pack. Specifically, the molten thermoplastic polymer from each inlet port is directed into a shared lateral flow passageway and individual portions of the incoming thermoplastic polymer are allocated from the lateral flow passageway to the outlet ports for subsequent distribution to the orifices in the spinneret plate. Because all of the inlet ports share a single lateral flow passageway, thermoplastic material streaming from adjacent inlet ports into the lateral flow passageway intersects, collides and mixes before arriving at the outlet ports. The intersecting streams of molten thermoplastic polymer may experience hold-ups, dead spots or stagnation zones, and/or recirculation within the lateral flow passageway. The individual streams of the polymer(s) from the outlet ports are ultimately supplied to the orifices in the spinneret.
The inability to uniformly divide the incoming stream of the molten thermoplastic polymer in the machine direction and in the cross-machine direction with uniform flow characteristics to the outlet ports causes unacceptable variations in the non-woven web formed by the spunbonding process. For example, non-uniform distribution of the molten thermoplastic polymer in cross-machine direction may cause the basis weight of the non-woven web to fluctuate in the cross-machine direction, which produces perceptible strips of varying basis weight extending parallel to the machine direction. In particular, the basis weight of the non-woven web originating from filaments extruded from spinneret orifices receiving thermoplastic polymer from outlet ports directly downstream of an inlet port has been observed to be significantly larger than the basis weight of the non-woven web originating from filaments extruded from spinneret orifices receiving thermoplastic polymer from outlet ports near the mid-point between adjacent inlet ports. The fluctuation in the basis weight is believed to arise from unequal flow path lengths in the shared lateral flow passageway. This results in non-uniform residence times and pressure drops for different portions of the non-Newtonian thermoplastic polymer exiting the outlet ports from the lateral flow passageway. The non-uniform flow path lengths also result in disparate shear histories for different portions of the thermoplastic polymer flowing in the lateral flow passageway reflected in the polymer properties and the characteristics of the non-woven web formed therefrom.
It would be desirable, therefore, to provide a spin pack for a melt-spinning apparatus capable of forming a non-woven web having improved basis weight uniformity in the cross-machine direction.
SUMMARY
In one aspect, the invention is directed to an apparatus for distributing thermoplastic material supplied to a spin pack of a meltspinning apparatus. The apparatus includes a linear flow equalizer having a plurality of flow passageways of substantially equal length that divide a flow of a thermoplastic material supplied from a plurality of liquid inlet ports into individual streams having a spaced relationship in a cross-machine direction.
In one specific embodiment of the apparatus of the invention, the linear flow equalizer includes an inlet plate having a plurality of liquid passageways spaced substantially equidistantly in a cross-machine direction of the meltspinning apparatus, a first equalizer plate positioned downstream from the inlet plate, and a second equalizer plate positioned downstream from the first equalizer plate. The first equalizer plate has elongated slots each centered about one of the plurality of liquid passageways. Each of the first plurality of elongate slots extends in the cross-machine direction and includes opposed closed ends substantially equidistant from one of the plurality of liquid passageways. The second equalizer plate has throughholes each substantially registered in alignment with one of the opposed closed ends of a corresponding one of the first plurality of elongated slots.
Another aspect of the invention is directed to a method of distributing thermoplastic material supplied to a spin pack to form a non-woven web. To that end, a flow of thermoplastic material is divided in a cross-machine direction of a spin pack among liquid passageways of substantially equal path length to form individual streams of thermoplastic material spaced in the cross-machine direction. The individual streams of thermoplastic material are shaped or formed into filaments, which are quenched, drawn, and collected to produce the non-woven web.
In accordance with the principles of the invention, the flows of thermoplastic material within the linear flow equalizer are partitioned homogeneously and symmetrically in the cross-machine direction and vertically in a downstream direction. The basis weight of the non-woven web produced by a melt spinning apparatus incorporating the linear flow equalizer of the invention is more uniform in the cross-machine direction. The improved uniformity in the basis weight is believed to arise from equal or nearly equal flow path lengths in the spin pack, which results in more uniform residence times and pressure drops for different divided portions of the thermoplastic polymer and approximately equal shear histories. As a result, the properties of the non-woven web are substantially independent of the lateral location of the outlet port from the final downstream equalizer plate relative to the individual inlets in the inlet plate. In accordance with the principles of the invention, the linear flow equalizer of the invention optimizes the flow distribution of the thermoplastic polymer(s) while achieving a uniform shear rate and a minimum residence time in the die pack.
These and other objects and advantages of the present invention shall become more apparent from the accompanying drawings and description thereof.
BRIEF DESCRIPTION OF THE FIGURES
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the principles of the invention.
FIG. 1 is a perspective view of a spin beam assembly;
FIG. 2 is a partial cross-sectional view taken generally along lines 2 — 2 in FIG. 1 ;
FIG. 3 is an exploded view of a linear flow equalizer for a spin pack in accordance with the principles of the invention;
FIG. 4 is a bottom view of the inlet plate of the spin pack of FIG. 3 ;
FIG. 5 is a cross-sectional view taken generally along lines 5 — 5 in FIG. 4 ;
FIG. 5A is a cross-sectional view similar to FIG. 5 in accordance with an alternative embodiment of the invention; and
FIG. 6 is a diagrammatic view of the flow paths for molten thermoplastic polymer in the linear flow equalizer of FIG. 3 .
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIGS. 1 and 2 , a spin beam assembly, generally indicated by reference numeral 10 , for forming filaments includes a chassis 12 holding drive pumps 14 , 15 , 16 , 17 each driven by a corresponding one of a set of motors 18 , 19 , 20 , 21 . The motors 18 – 21 are suspended from the chassis 12 by an open framework of beams 22 and generally overlie the drive pumps 14 – 17 . Extending from each of the motors 18 – 21 is a drive shaft 18 a , 19 a , 20 a , 21 a that supplies a drive coupling with a corresponding one of the drive pumps 14 – 17 . The spin beam assembly 10 is incorporated into a melt-spinning apparatus that includes conventional components, such as a filament-drawing device for attenuating the filaments and a moving collector located on a forming table, for forming a non-woven web.
Drive pumps 14 and 16 receive a flow of a first polymer (Polymer A) furnished by a supply line 23 from an extruder (not shown) and drive pumps 15 and 17 receive a flow of a second polymer (Polymer B) furnished by a separate supply line 24 from another extruder (not shown). The invention contemplates that the drive pumps 14 – 17 may be supplied by a single supply line communicating with and service by a single extruder. The first and second polymers may differ in composition, such as polyethylene and polypropylene, or may constitute two polymers of identical composition that differ with respect to a property such as melt flow rate or the presence or absence of an additive. The two polymers are heated to a temperature sufficient to produce a liquid or semi-solid material having a viscosity suitable for flow through an arbitrary set of passageways.
With continued reference to FIGS. 1 and 2 , a pump plate 26 attached to the chassis 12 supports the pumps 14 – 17 . Extending through the pump plate 26 is a plurality of liquid passageways 28 , of which two liquid passageways 28 are shown in FIG. 2 , arranged in rows such that each is coupled in fluid communication with an outlet of one of the drive pumps 14 , 16 . Also extending through the pump plate 26 is a plurality of liquid passageways 30 , of which one liquid passageway 30 is shown in FIG. 2 , each coupled in fluid communication with an outlet of one of the drive pumps 15 , 17 . Accordingly, each pump 14 , 16 outputs a stream of polymer A to the liquid passageways 28 and each pump 15 , 17 outputs a stream of polymer B to the liquid passageways 30 .
The spin beam assembly 10 further includes a spin pack, generally indicated by reference numeral 32 , supported by support brackets 34 , 36 within a housing 38 of chassis 12 . The spin pack 32 receives separate flows of the two polymers from the liquid passageways 28 , 30 in pump plate 26 . The spin pack 32 is an assembly that incorporates, in order from a top or upstream side to a bottom or downstream side, a linear flow equalizer 40 , a combining plate 42 , and a spinneret plate 44 . A major or long axis of the spin pack 32 is aligned generally parallel to a cross-machine direction 45 ( FIG. 1 ), which is generally orthogonal to a machine direction 46 . A collector (not shown) collects the filaments discharged from the spinneret plate 44 of spin pack 32 .
With reference to FIGS. 2 and 3 , the linear flow equalizer 40 is an assembly constituted by an inlet plate 48 and three equalizer plate sets 50 a–c . The inlet plate 48 includes inlet ports or passageways 52 , visible in FIG. 3 , arranged in three spaced linear rows to coincide with the locations of liquid passageways 28 , 30 . Adjacent inlet passageways 52 in each of the rows are spaced at equal centerline-to-centerline intervals, or a uniform pitch, across the width of the inlet plate 48 . In one specific embodiment of the invention, the inlet plate 48 features three rows of eight inlet passageways 52 .
Inlet passageways 52 in the center row are registered for fluid communication at an upstream surface 54 of inlet plate 48 with the liquid passageways 30 in the pump plate 26 . Similarly, inlet passageways 52 in the two rows flanking the center row are registered in fluid communication at the upstream surface 54 of inlet plate 48 with the liquid passageways 28 in the pump plate 26 . Accordingly, each inlet passageway 52 in the center row receives an output stream of polymer B from one of pumps 15 , 17 and each inlet passageway 52 in the rows flanking the center row receives an output stream of polymer A from one of pumps 14 , 16 . The rows of inlet passageways 52 in inlet plate 48 adjacent the front and rear edges of the spin pack 32 distribute respective output streams of Polymer A to the equalizer plate sets 50 a , 50 c . The central row of inlet passageways 52 distributes an output stream of Polymer B to the center equalizer plate set 50 b.
In accordance with the principles of the invention, the fluid pathways in the linear flow equalizer 40 define approximately equal length lateral and vertical flow paths and, preferably, equal length flow paths, for each polymer stream in a flow path extending from the downstream side of the pump plate 26 to the downstream side of each of the equalizer plate sets 50 a–c . The approximately equal lengths of the lateral and vertical flow paths in the linear flow equalizer 40 result in approximately uniform residence times and shear histories characterizing the polymer flows through the linear flow equalizer 40 . Preferably, the lateral and vertical flow paths for the polymers in the linear flow equalizer 40 are equal in length for providing optimum filament properties. Consequently, material properties of the resultant non-woven, such as basis weight, possess an improved uniformity in the cross-machine direction 45 .
With reference to FIGS. 3–5 , the inlet plate 48 includes shallow rectangular recesses or cavities 56 , 57 , 58 partitioned from one another by dividing walls 59 , 60 . Each of the cavities 56 , 57 , 58 is dimensioned to receive one of the equalizer plate sets 50 a–c . A downstream surface of each cavity 56 , 57 , 58 includes a series of shallow multi-segment channels 62 each centered about an outlet of one of the inlet passageways 52 . The channels 62 define a second stage or level of lateral and vertical thermoplastic material distribution in the linear flow equalizer 40 .
Each channel 62 includes a linear segment 64 extending in the cross-machine direction 45 and centered or symmetrical about inlet passageway 52 . Linear segment 64 terminates at each opposed open end in fluid communication with the center of a corresponding one of a pair of linear segments 66 each extending in the machine direction 46 . The linear segments 66 are equidistant in the cross-machine direction 45 from the corresponding inlet passageway 52 . Each of the linear segments 66 is centered or symmetrical about the intersection with linear segment 64 and terminates at each open end in fluid communication with a slotted linear segment 68 . Each slotted linear segment 68 extends in the cross-machine direction 45 and includes a pair of opposed curved terminal or closed ends 69 , 70 . Each slotted linear segment 68 is centered or symmetrical about the intersection with the corresponding one of the linear segments 66 . Therefore, the flow path length for the flowable thermoplastic material in each channel 62 is substantially equal and, preferably equal, from the inlet passageway 52 to the closed ends 69 , 70 of each slotted linear segment 68 .
As each of the equalizer plate sets 50 a–c have identical constructions, only one equalizer plate set 50 a is shown in FIG. 3 and is described herein. Equalizer plate set 50 a includes a plurality of, for example, five equalizer plates 72 , 74 , 76 , 78 and 80 , a sheet-forming plate 82 , removable mesh filters 83 , 84 , and 85 , a filter support plate 86 , and a seal 87 arranged in juxtaposition from the top or upstream side to the bottom or downstream side. The filter support plate 86 has a peripheral rim 88 surrounding a generally rectangular recess that captures the filters 83 , 84 , 85 in the set assembly. The equalizer plates 72 , 74 , 76 , 78 and 80 are secured together and fastened to the inlet plate 48 by conventional fasteners 90 extending from countersunk openings in the inlet plate 48 through appropriately aligned bolt holes formed in each of the equalizer plates 72 , 74 , 76 , 78 and 80 and secured by nuts 91 situated in countersunk openings on the downstream side of the sheet-forming plate 82 .
Each of the equalizer plates 72 , 74 , 76 , 78 and 80 is formed by milling or drilling a thin rectangular sheet of a suitable material using computer numerically controlled (CNC) machining. For example, equalizer plates 72 , 74 , 76 , 78 and 80 may be formed by CNC machining from sheets of a metal alloy, such as 17-4 stainless steel, having thermal expansion characteristics compatible with the surrounding metal environment of the spin pack 32 . The equalizer plats 72 , 74 , 76 , 78 and 80 may also be fabricated by alternative manufacturing techniques, such as by laser or chemical machining or by stamping.
With reference to FIG. 3 , equalizer plate 72 is positioned downstream of the inlet plate 48 and includes a plurality of flow passageways in the form of circular bores or thoughholes 92 extending vertically through the thickness of plate 72 from an upstream inlet to a downstream outlet. Contact between the equalizer plate 72 and the inlet plate 48 closes the channels 62 to define flow paths in equalizer plate 72 to the throughholes 92 . The throughholes 92 are arranged in two spaced linear rows such that each throughhole 92 is registered on an upstream surface 93 of plate 72 in substantial vertical alignment with one of the closed ends 69 , 70 of one of the slotted linear segments 68 in equalizer plate 72 . Adjacent throughholes 92 in each of the rows are spaced at equal centerline-to-centerline intervals, or a uniform pitch, across the width of the equalizer plate 72 . The throughholes 92 receive flowable thermoplastic material from the channels 62 in inlet plate 48 and define individual liquid inlets supplying flowable thermoplastic material to equalizer plate 74 . The channels 62 and the throughholes 92 collectively define a second stage or level of lateral and vertical thermoplastic material distribution in the linear flow equalizer 40 .
Equalizer plate 74 is positioned downstream of equalizer plate 72 and includes a plurality of slotted flow passageways 94 extending vertically through the thickness of plate 74 from an upstream inlet to a downstream outlet. A major axis of each slotted flow passageway 94 is aligned generally in the cross-machine direction 45 . The center of each slotted flow passageway 94 is registered on an upstream surface 99 of equalizer plate 74 in substantial vertical alignment with one of the throughholes 92 in equalizer plate 72 . Throughholes 92 and channels 62 cooperate to also divide the flow of thermoplastic material into two separate laterally-extending rows. As a result, opposed curved terminal or closed ends 96 , 98 of each slotted flow passageway 94 are substantially centered or symmetrical in the cross-machine direction 45 relative to the corresponding throughhole 92 .
With continued reference to FIG. 3 , equalizer plate 76 is positioned downstream of equalizer plate 74 and includes a plurality of flow passageways in the form of circular bores or thoughholes 100 extending vertically through the thickness of plate 76 from an upstream inlet to a downstream outlet. Each throughhole 100 is registered on an upstream surface 101 of equalizer plate 76 in substantial vertical alignment with one of the closed ends 96 , 98 of one of the slotted flow passageways 94 in equalizer plate 74 . Adjacent throughholes 100 in each of the rows are spaced at equal centerline-to-centerline intervals, or a uniform pitch, across the width of the equalizer plate 76 . The throughholes 100 in equalizer plate 76 and the slotted flow passageways 94 in equalizer plate 74 define a third stage or level of lateral and vertical thermoplastic material distribution in the linear flow equalizer 40 .
Equalizer plate 78 is positioned downstream of the equalizer plate 76 and includes a plurality of slotted flow passageways 102 extending vertically through the thickness of equalizer plate 78 from an upstream inlet to a downstream outlet. A major axis of each slotted flow passageway 102 is aligned substantially in the cross-machine direction 45 . The center of each slotted flow passageway 102 is registered on an upstream surface 108 of equalizer plate 78 in substantial vertical alignment with one of the throughholes 100 in equalizer plate 76 , which define individual liquid inlets supplying flowable thermoplastic material to equalizer plate 78 . As a result, opposed curved terminal or closed ends 104 , 106 of each slotted flow passageway 102 are substantially centered or symmetrical in the cross-machine direction 45 relative to the corresponding throughhole 100 .
With continued reference to FIG. 3 , equalizer plate 80 is positioned downstream of equalizer plate 78 and includes a plurality of flow passageways in the form of circular bores or thoughholes 110 extending vertically through the thickness of equalizer plate 80 from an upstream inlet to a downstream outlet. Each throughhole 110 is registered on an upstream surface 112 of equalizer plate 80 in substantial vertical alignment with one of the opposed closed curved ends 104 , 106 of one of the slotted flow passageways 102 . Adjacent throughholes 110 in each of the rows are spaced at equal centerline-to-centerline intervals, or a uniform pitch, across the width of the equalizer plate 80 . The throughholes 110 in equalizer plate 80 and the slotted flow passageways 102 in equalizer plate 78 define a fourth stage or level of lateral thermoplastic material distribution in the linear flow equalizer 40 .
The sheet-forming plate 82 includes opposed concavely-curved surfaces 114 , 116 that integrate or merge the individual liquid flows streaming from the throughholes 110 of equalizer plate 80 . Sheet-forming plate 82 effectively eliminates gaps between adjacent streams of molten thermoplastic polymer exiting the throughholes 110 to form a substantially uniform sheet of flowable thermoplastic material that is provided to the combining plate 42 . The flowable thermoplastic material is subsequently filtered by the downstream filters 83 , 84 , 85 before being supplied to openings 86 a extending through the filter support plate 86 .
With reference to FIG. 5A , each of the equalizer plate sets 50 a–c may be provided in an equalizer plate 71 in which a set of channels 62 a is formed. Each of the channels 62 a includes multiple linear segments, of which only linear segment 64 a is shown, arranged similarly or identical to channels 62 ( FIGS. 4 and 5 ). Channels 62 a are intended to replace channels 62 in inlet plate 48 ( FIGS. 4 and 5 ). Consequently, an inlet plate 48 a is modified to include three rows of inlet passageways 52 a each of which supplies thermoplastic material to the center of one channel 62 a for subsequent distribution to downstream equalizer plate 72 . Equalizer plate 71 is installed in recess 56 a of inlet plate 48 a between equalizer plate 72 and inlet plate 48 a and also in the other two recesses in inlet plate 48 a (not shown but similar to recesses 57 and 58 in FIG. 3 ).
The invention further contemplates that additional pairs of equalizer plates (not shown) may be disposed between equalizer plate 80 and sheet-forming plate 82 to provide additional symmetrical and equal divisions of the flowable thermoplastic material in the flow path through the linear flow equalizer 40 . The number of symmetrical and equal divisions will depend, among other variables, upon the width of the spin pack 32 in the cross-machine direction and, therefore, the width of the nonwoven web being formed by the spunbond system (not shown) with which spin beam assembly 10 is operative coupled.
With renewed reference to FIG. 3 , seal 87 provides a fluid-tight junction between a downstream side of the filter support plate 86 and an upstream side of the combining plate 42 . The combining plate 42 has internal liquid passageways 118 ( FIG. 2 ) configured to receive the sheet-like flows of flowable thermoplastic materials from each of the linear flow equalizers 40 and to combine the flows to generate a bicomponent filament arrangement, such as a sheath/core arrangement or a side-by-side arrangement. In a sheath/core arrangement, for example, the flow path within the combining plate 42 of one of the two polymers is interposed and brought into coaxial alignment with the flow path of the other of the two polymers and directed the spinneret plate 44 . The spinneret plate 44 has multiple spinneret holes or orifices 120 ( FIG. 2 ) registered with liquid outlets in the combining plate 42 from which bicomponent filaments 122 ( FIG. 2 ) are extruded for subsequent solidification, attenuation and collection as a non-woven web.
With reference to FIG. 6 , the operation of the linear flow equalizer 40 will be further explained. The flow path for a flowable thermoplastic material 124 through the linear flow equalizer 40 in a downstream direction from each inlet passageway 52 in inlet plate 48 to each throughhole 110 in equalizer plate 80 is substantially equal to or, preferable equal to, all other flow paths for the flowable thermoplastic material in the linear flow equalizer 40 . Therefore, the linear flow equalizer 40 divides the flow evenly among all flow paths so that the residence time of any arbitrary volume of flowable thermoplastic material 124 flowing between inlet passageway 52 and the corresponding throughholes 110 is approximately equal and, preferably equal, and so that the properties (e.g., shear history) of the flowable thermoplastic material 124 exiting from each throughhole 110 are substantially identical and preferably equal.
In the exemplary embodiment, the flowable thermoplastic material 124 entering the inlet passageways 52 is divided by inlet plate 48 into eight substantially equal portions, each of which is further subdivided by equalizer plates 72 , 74 into two substantially equal portions. It is understood that the number of substantially equal portions created by inlet plate 48 is dependent upon the width of the inlet plate 48 and equalizer plate sets 50 a–c in the cross-machine direction. Equalizer plates 76 , 78 further subdivide the portions received from equalizer plate 74 again into two substantially equal portions and directed through equalizer plate 80 to the combining plate 42 ( FIG. 2 ). In the combining plate 42 , the thermoplastic material 124 , for example, Polymer A is combined with another thermoplastic material 126 , for example, Polymer B, which is subdivided uniformly in the linear flow equalizer 40 in a manner substantially similar to thermoplastic material 124 . The combined thermoplastic materials 124 , 126 form bicomponent filaments 122 , such as the sheath/core arrangement illustrated in FIG. 6 , that are discharged from the spinneret orifices 120 in the spinneret plate 44 as a curtain of filaments 122 for subsequent collection. The invention contemplates that additional thermoplastic materials may be combined with the thermoplastic materials 124 , 126 to form multicomponent filaments 122 with more than two constituent thermoplastic materials and that the constituent thermoplastic materials may have other configurations, such as side-by-side.
While the present invention has been illustrated by a description of various embodiments and while these embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. For example, the principles of the invention may be applied for the formation of filaments composed of a single polymer or of filaments formed from more than two polymers. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant's general inventive concept. The scope of the invention itself should only be defined by the appended claims. | A linear flow equalizer for distributing thermoplastic material to a spin pack of a meltspinning apparatus that provides for uniform apportionment of a flow of a flowable thermoplastic material at least vertically and in a cross-machine direction of the spin pack. The linear flow equalizer includes an inlet plate with multiple liquid passageways equidistantly spaced in the cross-machine direction that each provide flowable thermoplastic material to a set of equalizer plates. Elongated slots extending through alternating equalizer plates are registered with throughholes extending through adjacent plates in the equalizer plate set. Each throughhole in an upstream equalizer plate is registered with the center of a corresponding slot and each throughole in a downstream equalizer plate is registered with one of opposed closed ends of a corresponding slot. | 3 |
BACKGROUND OF THE INVENTION
(i) Field of the Invention
The present invention relates to the prevention of scorching before crosslinking of a thermoplastic and/or elastomeric composition with peroxides or azo compounds.
(ii) Description of Related Art
Premature crosslinking (scorching) during the preparatory phase is a major difficulty in the use of peroxides and azo compounds in crosslinking (curing) applications of elastomeric and/or thermoplastic materials. The preparatory phase consists in general in blending the constituents and optionally extruding them at temperatures that are often high. The operating conditions of this preparatory phase quite often lead to decomposition of the peroxide or azo initiator, thus inducing the crosslinking reaction with formation of gel particles in the bulk of the blend. The presence of these gel particles leads to imperfections (inhomogeneity or surface roughness) of the final product. Excessive scorching reduces the plastic properties of the material, such that the said material can no longer be converted, leading to loss of the entire batch. In addition, excessive scorching may lead to the total stoppage of the extrusion operation.
Several solutions have been proposed to overcome this drawback. Thus, it has been proposed to use an initiator with a half-life of 10 hours at high temperature. The drawbacks of this approach are the low production efficiency due to a long curing time and the high energy costs.
It has also been proposed to incorporate certain additives in order to reduce the scorch tendency. Thus, the use of organic hydroperoxides as scorch inhibitors for polyethylene-based compositions crosslinked with a peroxide was described in British patent GB 1,535,039. The use of vinyl monomers was the subject of patent U.S. Pat. No. 3,954,907. The use of nitrites was described in patent U.S. Pat. No. 3,202,648. Patent U.S. Pat. No. 3,335,124 describes the use of aromatic amines, phenolic compounds, mercaptothiazole compounds, sulphides, hydroquinones and dialkyl dithiocarbamate compounds.
Very recently, the use of 2,2,6,6-tetramethylpiperidyloxy (TEMPO) and 4-hydroxy-2,2,6,6-tetramethylpiperidyloxy (4-hydroxy TEMPO) was the subject of a Japanese patent application JP 11-49865.
However, the use of the additives of the art cited above to increase the scorch-resistance time has a harmful effect on the curing time and/or on the final crosslinking density. It leads, therefore, to a reduction in the production efficiency and/or properties of the final product.
SUMMARY OF THE INVENTION
The present invention eliminates the drawbacks of the cited art since it makes it possible to improve the scorch resistance or the crosslinking density without this having a negative impact on the crosslinking time. This is achieved by using a nitroxide in combination with at least one crosslinking promoter (promoter) chosen from group (P) consisting of compounds containing at least one double bond, which may be difunctional or polyfunctional. Mention may be made, by way of example, of difunctional vinyl monomers, difunctional allylic monomers, polyfunctional vinyl monomers and polyfunctional allylic monomers.
The aim of the present invention is to provide a scorch-retardant composition comprising a nitroxide and at least one promoter chosen from the group (P). The nitroxide is preferably used in weight proportions ranging from 1:0.2 to 1:5 and advantageously between 1:0.5 and 1:2 relative to the amount of promoter present.
One aim of the present invention is also to provide a scorch-retardant curing/crosslinking composition (A), comprising a free-radical initiator chosen from the group consisting of organic peroxides, azo compounds and mixtures thereof, a nitroxide and at least one promoter chosen from the group (P). The free-radical initiator is preferably used in weight proportions of from 1:0.02 to 1:1 and advantageously from 1:0.1 to 1:0.5 relative to the amount of nitroxide present.
The free-radical initiator is preferably used in weight proportions of from 1:0.02 to 1:1 and advantageously from 1:0.1 to 1:0.5 relative to the amount of promoter used.
The present invention also provides a crosslinkable composition (B) comprising a thermoplastic polymer and/or an elastomeric polymer which may be crosslinked by means of a peroxide or an azo compound, a free-radical initiator chosen from the group consisting of organic peroxides and azo compounds and mixtures thereof, a nitroxide and at least one promoter chosen from group (P). The free-radical initiator preferably represents between 0.2 and 5 parts and advantageously between 0.5 and 3 parts per 100 parts by weight of polymer. The proportions of nitroxide and of promoter used relative to the free-radical initiator are preferably in the region of those used for composition (A).
The present invention also provides a process for crosslinking a crosslinkable composition comprising a thermoplastic polymer and/or an elastomeric polymer which may be crosslinked using a peroxide or an azo compound, in which the said polymer is mixed with a free-radical initiator chosen from the group consisting of organic peroxides, azo compounds and mixtures thereof, in the presence of a nitroxide combined with at least one promoter chosen from the group (P).
The present invention also provides molded or extruded articles such as wires and electrical cables obtained from a crosslinkable composition (B).
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Advantageously, the promoters chosen from the group (P) are trans-stilbene, divinylbenzene, trans, trans-2,6-dimethyl-2,4,6-octatriene, dicyclopentadiene, 3,7-dimethyl-1,3,6-octatriene (OCIMENE), the compounds represented by the general formula (I):
in which R x represents a hydrogen atom or an alkyl group of 1 to 9 carbon atoms and n is an integer between 1 and 3,
and the compounds represented by the general formula (II):
in which R y and R z , which may be identical or different, represent an alkyl group of 1 to 4 carbon atoms.
As to compounds represented by the general formula (I), mention may be made of α-methylstyrene, ortho-, meta- and para-diisopropenylbenzene, 1,2,4-triisopropenylbenzene, 1,3,5-triisopropenylbenzene, 3-isopropyl-ortho-diisopropenylbenzene, 4-isopropyl-ortho-diisopropenylbenzene, 4-isopropyl-m-diisopropenylbenzene, 5-isopropyl-m-diisopropenylbenzene and 2-isopropyl-p-diisopropenylbenzene.
As to compounds represented by the general formula (TII), mention may be made of 2,4-bis(3-isopropylphenyl)-4-methyl-1-pentene, 2,4-bis(4-isopropylphenyl)-4-methyl-1-pentene, 2-(3-isopropylphenyl)-4-(4-isopropylphenyl)-4-methyl-1-pentene, 2-(4-isopropylphenyl)-4-(3-isopropylphenyl)-4-methyl-1-pentene, 2,4-bis(3-methylphenyl)-4-methyl-1-pentene and 2,4-bis(4-methylphenyl)-4-methyl-1-pentene.
Methyl methacrylate, lauryl methacrylate, allyl methacrylate, trimethylolpropane triacrylate, triallyl cyanurate (TAC), triallyl isocyanurate (TAIC), triallyl phosphate, tetraallyloxyethane, diallyldiglycol carbonate, triallyl trimellitate, triallyl citrate, diallyl adipate, diallyl terephthalate, diallyl oxalate, diallyl fumarate, ethylene glycol dimethacrylate and 2-hydroxyethyl methacrylate may also be suitable as promoters.
Compounds suitable as promoters from the group (P) may also include the compounds represented by the general formula (X)
in which n is 1 or 2 and R is divalent or trivalent and comprises aliphatic acyclic groups having 2 to 16 carbon atoms, aliphatic cyclic groups having 5 to 20 carbon atoms, aromatic groups having 6 to 18 carbon atoms and alkyl aromatic (alkylaryl) groups having 7 to 24 carbon atoms, and these divalent or trivalent groups may contain one or more oxygen, nitrogen and/or sulphur heteroatoms in replacement of one or more carbon atoms, and each R 1 is identical and represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms.
Among the compounds of general formula (X), the bismaleimides and the biscitraconimides are advantageously selected.
As to bismaleimide, mention may be made of N,N′-m-phenylenebismaleimide, N,N′-ethylenebismaleimide, N,N′-hexamethylenebismaleimide, N,N′-dodecamethylenebismaleiminde, N,N′-(2,2,4-trimethylhexamethylene)bismaleimide, N,N′-(oxydipropylene)bismaleimide, N,N′-(aminodipropylene)bismaleimide, N,N′-(ethylenedioxydipropylene)bismaleimide, N,N′-(1,4-cyclohexylene)bismaleimide, N,N′-(1,3-cyclohexylene)bismaleimide, N,N′-(methylene-1,4-dicyclohexylene)bismaleimide, N,N′-(isopropylidene-1,4-dicyclohexylene)bismaleimide, N,N′-(oxy-1,4-dicyclohexylene)bismaleimide, N,N′-p-(phenylene)bismaleimide, N,N′-(o-phenylene)bismaleimide, N,N′-(1,3-naphthylene)bismaleimide, N,N′-(1,4-naphthylene)bismaleimide, N,N′-(1,5-naphthylene)bismaleimide, N,N′-(3,3′-dimethyl-(4,4-diphenylene)bismaleimide, N,N′-(3,3-dichloro-4,4-biphenylene)bismaleimide, N,N′-(2,4-pyridyl)bismaleimide, N,N′-(2,6-pyridyl)bismaleimide, N,N′-(1,4-anthraquinonediyl)bismaleimide, N,N′-(m-tolylene)bismaleimide, N,N′-(p-tolylene)bismaleimide, N,N′-(4,6-dimethyl-1,3-phenylene)bismaleimide, N,N′-(2,3-dimethyl-1,4-phenylene)bismaleimide, N,N′-(4,6-dichloro-1,3-phenylene)bismaleimide, N,N′-(5-chloro-1,3-phenylene)bismaleimide, N,N′-(5-hydroxy-1,3-phenylene)bismaleimide, N,N′-(5-methoxy-1,3-phenylene)bismaleimide, N,N′-(m-xylylene)bismaleimide, N,N′-(p-xylylene)bismaleimide, N,N′-(methylenedi-p-phenylene)bismaleimide, N,N′-(isopropylidenedi-p-phenylene)bismaleimide, N,N′-(oxydi-p-phenylene)bismaleimide, N,N′-(thiodi-p-phenylene)bismaleimide, N,N′-(dithiodi-p-phenylene)bismaleimide, N,N′-(sulphodi-p-phenylene)bismaleimide, N,N′-(carbonyldi-p-phenylene)bismaleimide, α,α′-bis(4-maleimidophenyl)-meta-diisopropylbenzene, α,α′-bis(4-p-phenylene)bismaleimide and α,α′-bis(4-maleimidophenyl)-para-diisopropylbenzene.
As to biscitraconimides, mention may be made of the following:
1,2-N,N′-dimethylenebiscitraconimide; 1,2-N,N′-trimethylenebiscitraconimide; 1,5-N,N′-(2-methylpentamethylene)biscitraconimide; and N,N′-(methylphenylene)biscitraconimide.
The compounds of general formula (X) are preferably selected so as to crosslink the elastomers.
Nitroxides which may be used, for example, are those represented by the general formula (III):
in which R 1 , R 2 , R 3 , R 4 , R′ 1 and R′ 2 , which may be identical or different, represent a hydrogen atom, a halogen atom such as fluorine, chlorine, bromine or iodine, a linear, branched or cyclic, saturated or unsaturated hydrocarbon-based group such as an alkyl or phenyl radical, a polymer chain which may be, for example, a polyalkyl (meth)acrylate chain, for instance polymethyl methacrylate, a polydiene, polyolefin or polystyrene chain, a functionalized group such as a cyano —CN group, an ester —COOR group, an amide —CON(R) 2 group, an alkoxy —OR group or a phosphonate —PO(OR) 2 group in which R represents a hydrocarbon-based chain containing from 1 to 9 carbon atoms. In addition, R′ 1 and R′ 2 may be linked together to form a ring such as, for example, the nitroxides represented by the following formulae:
in which R 5 , R 6 , R 7 and R 8 , which may be identical or different, may comprise the same family of groups as that which has just been envisaged for R 1 , R 2 , R 3 and R 4 and, furthermore, may represent a hydroxyl —OH group, an acid group such as —COOH or —PO(OH) 2 or —SO 3 H. Furthermore, X in formula (VI) represents a divalent group comprising methylene, —CH 2 —, —C(OR)(OR′)—, carbonyl —C(O)—, oxy —O— and —CHZ—with Z representing a monovalent residue comprising cyano: —CN, amino: —NRR′, alkoxy: —OR, iminoyl —N═CRR′, carboxylate: —OC(O)—R and amide: —NHR—C(O)R′ groups, in which R and R′, which may be identical or different, represent a hydrogen atom, a linear or branched alkyl group containing a number of carbon atoms ranging from 1 to 10, or a benzyl or phenyl group. X in formula (VI) may also represent a phosphonate group: —OP(O)R″R′″with R″ and R′″ having the same meaning as Z.
It is also possible to use the nitroxides represented by the general formula (VII)
in which R 1 , R 2 , R 3 and R 4 , which may be identical or different, have the same meaning as those used for formulae (III) to (VI) and Y represents a divalent group comprising:
—OC(O)—(CR a R b ) n —C(O)O—,
—NH—(CR a R b ) n NH—,
—NHC(O)—(CR a R b ) n —C(O)NH—,
—S—, —O—; R a and R b , which may be identical or different, represent a hydrogen atom or a linear or branched alkyl radical containing a number of carbon atoms ranging from 1 to 10 and n represents an integer ranging from 0 to 20.
In addition, it is possible to use the nitroxides represented by the general formula (VIII):
in which R 1 , R 2 , R 3 and R 4 , which may be identical or different, have the same meaning as those in the above formulae (III) to (VII), λ is an integer between 1 and 20, R 9 represents an alkylene group containing a number of carbon atoms ranging from 2 to 12 which may be interrupted with an —O— or —NR 10 — with R 10 denoting a hydrogen atom, an alkyl group containing a number of carbon atoms of between 1 and 12, or a cycloalkyl group, and Q represents a radical —OR 11 , —NHR 12 or —NR 12 R 13 in which R 11 represents a linear or branchecd alkyl radical containing a number of carbon atoms ranging from 1 to 12, a C 3 -C 12 alkoxyalkyl radical, a cyclohexyl radical, a benzyl radical, a phenyl radical, a tolyl radical or a 2,2,6,6-tetrapiperidyl residue, R 12 and R 13 have the same meaning as R 11 and may moreover also form, together and with the nitrogen atom which bears them, a 5-, 6- or 7-membered heterocyclic radical which may also contain an oxygen.
The nitroxides of general formula (VIII) that are usually used are those obtained by oxidation of the amines sold by the company CIBA under the name Chimasorb 944 in which R 1 , R 2 , R 3 and R 4 each denote a methyl group, R 9 denotes an alkylene group containing 6 carbon atoms, Q represents a radical —N(O)—C 8 H 11 and λ is an integer between 2 and 4.
The nitroxides of general formula (VI) that are preferred are those for which R 1 , R 2 , R 3 and R 4 each denote a methyl group, R 5 , R 6 , R 7 and R 8 each represent a hydrogen atom and X represents a group —CHZ—.
In particular, nitroxides of general formula (VI) which may be mentioned are 2,2,6,6-tetramethyl-1-piperidyloxy, generally sold under the name TEMPO, 4-hydroxy-2,2,6,6-tetramethyl-1-piperidyloxy, sold under the name 4-hydroxy TEMPO, 4-methoxy-2,2,6,6-tetramethyl-1-piperidyloxy, commonly known as 4-methoxy TEMPO, and 4-oxo-2,2,6,6-tetramethyl-1-piperidyloxy, commonly known as 4-oxo TEMPO.
The nitroxides of general formula (VI) that are particularly preferred are those represented by the following formula:
with n possibly ranging from 1 to 20.
Nitroxides such as 2,2,5,5-tetramethyl-1-pyrrolidinyloxy, sold under the brand name PROXYL, bis(1-oxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, sold under the brand name CXA 5415 by the company Ciba Specialty Chemical, 2,2,6,6-tetramethyl-4-hydroxy-1-piperidyloxy monophosphonate and 3-carboxy-2,2,5,5-tetramethylpyrrolidinyloxy (commonly known as 3-carboxy Proxyl) are also preferred.
According to the present invention, compounds which may be used as free-radical initiators are azo compounds and/or organic peroxides, which, upon thermal decomposition, produce free radicals which facilitate the curing/crosslinking reaction. Among the free-radical initiators used as crosslinking agents, dialkyl peroxides and diperoxyketal initiators are preferred. A detailed description of these compounds is found in Encyclopedia of Chemical Technology , 3rd edition, vol. 17, pages 27 to 90 (1982).
Among the dialkyl peroxides, the preferred initiators are: dicumyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-amylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne, 2,5-dimethyl-2,5-di(t-amylperoxy)-3-hexyne, α,α-di[(t-butylperoxy)isopropyl]benzene, di-t-amyl peroxide, 1,3,5-tri[(t-butylperoxy)isopropyl]benzene, 1,3-dimethyl-3-(t-butylperoxy)butanol and 1,3-dimethyl-3-(t-amylperoxy)butanol, and mixtures thereof.
Among the diperoxyketals, the preferred initiators are: 1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-di(t-butylperoxy)cyclohexane, n-butyl 4,4-di(t-amylperoxy)valerate, ethyl 3,3-di(t-butylperoxy)butyrate, 2,2-di(t-amylperoxy)propane, 3,6,6,9,9-pentamethyl-3-ethoxycarbonylmethyl-1,2,4,5-tetraoxacyclononane, n-butyl 4,4-bis(t-butylperoxy)valerate and ethyl 3,3-di(t-amylperoxy)butyrate, and mixtures thereof.
Azo compounds which may be mentioned, for example, are 2,2′-azobis(2-acetoxypropane), azobisisobutyronitrile, azodicarbamide, 4,4′-azobis(cyanopentanoic acid) and 2,2′-azobismethylbutyronitrile.
Dicumyl peroxide and α,α′-di[(t-butylperoxy)isopropyl]benzene are particularly preferred.
The thermoplastic and/or elastomeric polymers taken into consideration in the present invention may be defined as natural or synthetic polymers which have a thermoplastic and/or elastomeric nature and which may be crosslinked (cured) under the action of a crosslinking agent. In Rubber World, “Elastomer Crosslinking with Diperoxyketals ”, October 1983, pages 26-32, and in Rubber and Plastic News, “Organic Peroxides for Rubber Crosslinking ”, 29 Sep. 1980, pages 46-50, the crosslinking action and crosslinkable polymers are described. Polyolefins which are suitable for the present invention are described in Modern Plastics Encyclopaedia 89, pages 63-67 and 74-75. By way of example of polymers and/or elastomers, mention may be made of linear low density polyethylene, low density polyethylene, high density polyethylene, chlorinated polyethylene, ethylene/propylene/diene terpolymers (EPDM), ethylene/vinyl acetate copolymers, ethylene/propylene copolymers, silicone rubber, natural rubber (NR), polyisoprene (IR), polybutadiene (BR), acrylonitrile-butadiene copolymers (NBR), styrene-butadiene copolymers (SBR), chlorosulphonated polyethylene and fluoroelastomers.
Mention may also be made of ethylene/methyl (meth)acrylate copolymers and ethylene/glycidyl methacrylate copolymers.
In addition to the constituents mentioned above, the compositions (A) and (B) may comprise antioxidants, stabilizers, plasticizers and inert fillers such as silica, clay or calcium carbonate.
The compositions (A) and (B) may comprise two or more nitroxides (N). They may also comprise two or more free-radical initiators.
According to the process of the present invention, the crosslinking temperature may be between 110 and 220° C. and preferably between 140 and 200° C.
Advantageously the process is implemented in the presence of an amount of initiator, nitroxide and promoter such that the initiator/polymer, nitroxide/polymer and promoter/polymer weight ratios are close to the composition (B).
The conversion of the crosslinkable compositions into molded or extruded articles may be carried out during or after crosslinking.
Experimental Section
In the text hereinbelow, the following abbreviations are used:
M H : the maximum value of the torque obtained from the curve recorded by the rheometer. This value determines the crosslinking density. T 90 : crosslinking time, the time required to reach 90% of the maximum torque. T s5 : scorch time, the time required at a given temperature for the torque to increase by 5 Mooney units.
The crosslinking density (M H ) and the crosslinking time (T 90 ) of the blend obtained were measured at 180° C. using a Monsanto ODR 2000 E rheometer (Alpha Technologies, oscillation arc: 3, oscillation frequency: 100 cycles/min).
The crosslinking time is also determined using the rheometer used under the same conditions as above.
The scorch time was measured at 145° C. using a Mooney MV 2000 viscometer (Alpha Technologies).
EXAMPLE 1
Not in Accordance with the Invention
1000 g of low density polyethylene (Mitene sold by Ashland), 25 g of dicumyl peroxide (Luperox® DC) and 3 g of 2,2,6,6-tetramethylpiperidyloxy (TEMPO) were mixed together in a turbomixer at 80° C. (nominal temperature) for 15 minutes (stirring speed=930 rpm). The powder was then converted into a sample in the form of a disc by melting at 110° C. for 3 min. The sample was then placed in the rheometer or viscometer chamber.
EXAMPLE 2
Not in Accordance with the Invention
Example 1 was repeated without the use of 2,2,6,6-tetramethylpiperidyloxy. The results are given in Table 1. Comparison of Examples 1 and 2 shows that the scorch time is higher in Example 1, but is accompanied by a large reduction in crosslinking density and by a slight increase in the crosslinking time.
EXAMPLE 3
Example 1 was repeated, adding 3 g of diisopropylbenzene (DIPB).
Comparison of the results with those obtained in the above examples shows unambiguously that such a combination makes it possible to maintain an increase in the scorch time while at the same time giving a higher crosslinking density and a lower crosslinking time.
TABLE 1
Cross-
Maximum
Scorch
linking
torque at
time at
time at
180° C.
145° C.
180° C.
(M H )
(T s5 )
(T 90 )
Additive(s)
(N.m)
(min/s)
(min/s)
Example 1
TEMPO
1.21
19:00
7:10
Example 2
—
1.95
8:40
6:50
Example 3
TEMPO + DIPB
2.88
19:10
6:02
Example 4
—
5.94
2:50
5:21
Example 5
OH-TEMPO
5.14
16:19
5:39
Example 6
MBM
6.61
1:43
3:54
Example 7
OH-TEMPO +
6.45
14:38
4:46
MBM
EXAMPLE 4
Not in Accordance with the Invention
318 g of compound EPDM DIN 7863 (containing 100 g of ethylene-propylene-diene terpolymer and 218 g of fillers) were conditioned in a Banbury-type mixer with a volume of 350 cm 3 at 50° C. for 5 minutes at a speed of 50 revolutions/min. 8 g of Luperox F40ED (40% di(tert-butylperoxyisopropyl)benzene and 60% inert fillers) were added and mixed with the compound for 5 minutes at 50° C. at a speed of 50 revolutions/min.
EXAMPLE 5
Not in Accordance with the Invention
Example 4 is repeated but with the addition not only of Luperox F40ED but also of 0.677 g of 4-hydroxy-2,2,6,6-tetramethylpiperidyloxy (OH-TEMPO).
EXAMPLE 6
Not in Accordance with the Invention
Example 5 is repeated but adding, instead of the OH-TEMPO, 0.5 g of N,N′-m-phenylenedimaleide (N,N′-m-phenylenebismaleimide or MBM).
EXAMPLE 7
Example 5 is repeated but with the addition not only of Luperox F40ED and OH-TEMPO but also of 0.5 g of MBM. | The present invention relates to the prevention of scorching before crosslinking of a thermoplastic and/or elastomeric composition with peroxides or azo compounds. This is achieved by using a nitroxide in combination with at least one crosslinking promoter (promoter) chosen from group (P) consisting of compounds containing at least one double bond, which may be difunctional or polyfunctional. | 2 |
FIELD OF THE INVENTION
This invention relates to light weight structural beams and more particularly to electrically insulative light weight structural beams of high mechanical and dielectric strengths. Even more particularly, the beam is for use in high load-bearing situations, with the load generally being applied at one end of the beam and with the beam being supported at the other end. A common use for such a beam is as part of an aerial lift device, supporting or lifting heavy equipment or a cage for carrying one or more persons.
BACKGROUND OF THE INVENTION
A common use for light weight high strength beams can be found in boom trucks--trucks that are used to lift a cage or similar containing a person and/or machinery to an elevated position. Such trucks may be employed in maintenance of buildings, high voltage wires, telephone wires, and the like, or in attending to trees, especially fruit trees, or a variety of other applications. In these boom trucks, it is important that the boom be as strong as possible so that a maximum amount of weight can be supported at the outer end thereof. It is also important that the boom be as long as possible, or at least as long as required, so that desired elevated positions can be reached.
It is also necessary that the beam be as strong as possible, but also be as light weight as possible in order not to add unnecessarily to the overall weight of the boom, since the beam must also support its own weight.
Such beams typically experience tensile stresses in their upper region and compressive stress in their lower region. Further, when the beams are subject to cantilever bending they also experience shear stresses in their side walls. Torsional load will also create additional shear stresses.
In order to construct a beam that can provide resistance to all these types of stresses, especially with these stresses being fairly high, and also provide a light enough weight beam, a composite material or materials are typically used. Further, such materials are typically formed into a beam by a multi-step method of manufacture.
Another very important characteristic of the beam is that it has an extremely high dielectric strength. The beam must be able to withstand a very high voltage applied thereto while allowing an electrical current that is in the order of a few microamperes to pass. Such an electrical condition can occur if the beam comes in contact with hydro wires. Indeed, it is necessary that the beam be able to withstand and insulate high electrical voltages in order to protect anyone working in a bucket suspended at the end of the boom. It is usual for workmen working on high voltage electrical power lines (in the order of up to several hundred thousand volts) to work on those lines live--that is, the lines are operating while being worked on.
It is therefore necessary that the material or materials used have a high dielectric strength. It is necessary that the beam not have any voids therein, to preclude the trapping of moisture. Having moisture trapped with the beam, whether in voids within the material, or in voids between material parts, could allow for electrical conductance, sufficient enough to make the beam unsafe.
The above mentioned properties of the beam are necessary in order for a boom truck using such a beam to be safe. The ultimate safety of the boom truck is also dependent on proper installation of the beam therein and subsequent safe use, so that the above mentioned properties of the beam are not comprised.
DESCRIPTION OF THE PRIOR ART
Reference will now be made to FIGS. 1 and 2 which show the prior art beam that is most similar to the invention described herein, has a hollow core with a glass filament winding wrapped therearound. The beam is formed by wrapping a resin soaked glass filament winding around a solid mandrel of generally square cross-section with rounded corners. The mandrel and the glass filament winding therearound are best shown in FIG. 1. The resin is then allowed to set, and the mandrel is removed thus leaving a hollow beam. The resulting beam is somewhat rounded around its perimeter, which is not acceptable in most cases.
In order to make the sides of the beam generally planar, the four sides are cut to a generally planar shape as shown in FIG. 2. Such cutting of the material is detrimental to the strength of the beam because the glass filament is not continuous but is merely many cut strands. The cross-section of the finished beam is shown in FIG. 2.
Further, it has been found that the prior art beam typically has a glass filament content in the range of about 65% by weight, which is less than a typical amount of 75% for the invention disclosed herein. Resultingly, this detracts from the strength and modulus of elasticity of the Prior Art beam.
SUMMARY OF THE INVENTION
The present invention provides a composite beam of high strength and of light weight that is suitable for use in aerial lift devices and the like. The beam is made of three distinct layers, an inner structural layer, a middle structural layer, and an outer structural layer. The inner structural layer comprises a glass filament winding that has been saturated in resin and subsequently cured, around a central hollow core. The middle structural layer comprises a set of four plates placed around the inner structural layer, with the four plates being composed of a cured resin material with glass fibre roving therein. The plates are pre-molded and cured prior to winding. The glass fibre roving is generally unidirectionally aligned along the plates. Around the middle structural layer is an outer structural layer that is comprised of layers of woven or non-woven fibre material that have been saturated with resin and thereafter cured. It may indeed be a chopped strand mat of fibreglass, which is non-woven. Alternatively, it may be a woven roving. Further, it may be any sort of similar woven or non-woven material.
The resin may be chosen from many types of polymer, and in preferably an epoxy, an unsaturated polyester or a vinylester.
The beam of the present invention also provides a beam having virtually no voids, either in the materials of between the various material parts. This lack of voids causes the beam to have very high compressive and tensile strength and also allows the beam to preclude the intrusion of moisture, which can drastically affect the dielectric strength. The beam of the present invention is highly resistant to electrical current flow and is able to withstand and insulate high electrical voltages.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of this invention will now be described by way of example in association with the accompanying drawings, in which:
FIG. 1 is a cross-sectional view of a prior art beam during manufacture;
FIG. 2 is a cross-sectional view of a prior art beam after the manufacturing process is complete;
FIG. 3 is a cross-sectional view of the beam of the present invention; and
FIGS. 4 through 13 are cross-sectional views of the mold used to form the beam and the various components or the beam; and
FIG. 14 shows an alternative embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made to FIG. 3, which shows a beam 20 having a hollow core 22, an inner structural layer 24 around said core 22, a middle structural layer 30 around the inner structural layer 24, and an outer structural layer 50. It has been found that various thicknesses of these layers may be suitable depending on specific requirements. One example of these thicknesses is about 1/8" for the outer structural layer, 1/2" for the middle structural layer, and 1/8" for the inner structural layer. These thicknesses are fairly representative of typical sizes for these layers. Of course, these layers may be any thickness depending on the engineering requirements of the beam.
The inner structural layer 24 comprises a continuous filament wound in layers of continuous roving along the length of the beam 20 impregnated with resin and cured. The filament 25 is saturated with cured resin. The angle that the filament 25 is, measured with respect to the longitudinal axis of the beam, can be anywhere between 20° and about 85°. The angle used for the wound filament 25 within any particular beam depends on the required properties of the beam. It has been found that in order to resist hoop stress, the winding angle should be closer to the maximum angle of 85°. It has also been found that in order to resist longitudinal stress, the winding angle shall be closer to the minimum angle of 20°. It have been found that the ideal and for resisting twisting moment is 45°.
Around the inner structural layer 24 is a middle structural layer 30 that comprises a series of four pre-molded plates, a first plate 32, a second plate 34, a third plate 36, and a fourth plate 38. The first plate 32, which is generally considered the top plate, has edges 42 that are in intimate contact with portion of the side of the third and fourth plates 36, 38. The second plate 34, which is usually the bottom plate, is in intimate contact at portions of its side with one edge 46 of third plate 36 and with one edge 48 of fourth plate 38. Together, these four pates form the middle structural layer 30, with one side of each of these plates being in intimate contact with the inner structural layer 24.
The plates are pre-molded and composed of a cured resin material having a fibre roving, with the fibres being generally unidirectional and substantially aligned lengthwise along the plates. The plates are generally planar, but are shaped to some degree near their corners in order that the inner and outer surfaces formed by the four plates have rounded rather than squared corners, as viewed in cross-section. The plates must be designed to fit properly between the inner and outer structural layers and must full all of the space between the inner and outer structural layers. The cross-section shapes of the plates are predetermined depending on the shape of the inner and outer structural layers. As viewed in cross-section, the corners of the plates, may be square or radiused; the sides of the plates may be straight or curved.
Around the middle structural layer is an outer structural layer 50. This outer structural layer 50 comprises layers of a chopped strand mat or woven roving or a similar woven or non-woven fibre material, wrapped around the middle structural layer 30. The material is soaked in resin, which is subsequently cured.
The inner structural layer 24 and the outer structural layer 50 serve to encase and generally support the middle structural layer 40. Further, the inner and outer layers 24 and 50 add substantially to the torsional strength and to the shear strength of the beam 20.
The middle structural layer 30 provides the main component for resisting the compressive and tensile forces experienced by the beam while the beam is supporting a load. The resistance to these forces is quite high, which means the beam is of a very high strength, especially in terms of lifting loads at or near one end thereof while supported at the other.
A very important factor to be considered in safe beam design is the maximum bending moment of the beam. This maximum bending moment occurs at the fixed end of the beam. The maximum bending moment is in a typical case expressed as a product of the loading arm and the load at certain points along the beam. The loading arm "L" is defined as the distance between the fixed end of the beam and the application point of the load of weight "W". The maximum bending moment "M" is defined as M=L×Weight×Cosine A, where "A" is the angle between the beam and horizontal. This angle changes as a beam is raised or lowered. As a beam is raised, the angle "A" increases, which means that the bending moment is decreased.
Additionally, if the beam is also supporting a cable, the cable extending from a winch mounted at the support point of the beam to a pulley located on the loading end of the beam, the beam is also subjected to an additional compressive stress. This additional compressive stress is equal to the quotient of the weight supported by the cable divided by the cross-sectional area of the beam.
Another important consideration when calculating the maximum loading of a beam is the vertical deflection of the beam when the beam is exposed to a load of weight "W". The vertical deflection will vary depending on the modulus of elasticity "E" of the material in a longitudinal direction along the beam and of the moment of inertia "I" of the cross-section of the beam. The vertical deflection "y" is typically expressed in terms of the following parameters: y=k (W×L 3 ) / (E×I) where "k" is a constant. If the material has a high modulus of elasticity in a longitudinal direction along the beam, the deflection of the beam for a given load will be smaller. A smaller deflection, provides increased stability when the beam is loaded. Further, the ability of the beam to resist buckling is increased. This is especially important in the case of a thin walled beam which may be inherently prone to failure caused by buckling due to compression in the sides and bottom wall of the beam.
The thickness of each of the pre-molded plates 32, 34, 36 and 38 of the middle structural layer 30 can be varied, depending on design requirements. A thicker plate would of course provide more strength in tension and in compression. Typically, the plate that is to be on the bottom of the beam should be thicker than the plate on the top because the plate on the bottom is in compression and the compressive strength of such constructed plates is less than the tensile strength. The mass of the beam can also be minimized if the thickness of the plates is minimized.
Thinner plates are also desirable in order to reduce the amount of heat energy emitted by the exothermic reactions during the curing of the resins. If excessive heat is encountered during the curing, cracking of the resin can result. Further, thinner plates with higher glass content will shrink less during curing.
Reference will now be made to FIGS. 4 through 11 which show a method by which the beam is manufactured. A first mold portion 60, which is generally "U" shaped, is put in place with the opening of the "U" shape facing upwardly. A chopped strand mat 62 that has been soaked in resin, is placed in the first mold portion 60 such that the chopped strand mat 62 is in intimate contact with the inside surface of the first mold portion 60. A portion of the chopped strand mat 62 projects outwardly from each edge of the first mold portion 60 as can be best seen in Figure 5. The total amount of chopped strand mat projecting therefrom is preferably enough to span across the opening of the "U" shaped first mold portion.
FIG. 6 shows that after the chopped strand mat 62 is in place, the second plate 34 is placed in the "U" shaped first mold portion 60 on top of the chopped strand mat 62. The second plate 34 lies on top of the resin filled chopped strand mat 62, with the distance between the second plate 34 and the inner surface of the first mold portion 60 defining the thickness of the bottom part of the inner structural layer.
The third and fourth plates 36, 38 are then placed in the first mold portion 60 such that the bottom edge of each is in intimate contact with the surface of second plate 34, and one side of each presses against the resin filled chopped strand mat 62. The distance between the outer surface of each of third and fourth plates 36, 38 and the inner surface of the first mold portion 60 defines the thickness of the sides of outer structurally layer 50.
The next step comprises taking a mandrel 70, which is in the shape of the hollow core 22 of the beam, and winding continuous filament 72 around the mandrel 70 in layers of continuous roving along the length thereof. The continuous filament 72 is first soaked in a quantity of resin, and then wound around the mandrel 70. The combination of the continuous filament 72 and the resin forms the inner structural layer 24.
The combination of the mandrel and the inner structural layer 24 formed therearound, are then placed into the "U" shaped mold 60 within the confines of the third and fourth plates 36, 38 and on top of the second plate 34. The resin which is as yet uncured and still in its liquid state. The first plate 32 is then placed on the inner structural layer 24. Any excess of resin in the inner structural layer escapes from underneath the first plate 32 through the interfaces between first plate 32 and third and fourth plates 36, 38.
The portions of the chopped strand mat 62 that were left protruding from the first mold portion 60 are then folded over the first plate 32. A second mold portion 74 is then placed over the entire assembly such that it spans across the opening of the "U" shaped first mold portion 60. The components of the beam are thus completely encased. Again, the resin flows to fill any voids, and any excess resin escapes between the interface between first mold portion 60 and second mold portion 74.
Pressure is applied to various portions of the two mold portions in order remove all entrained air and excessive resin. The resin is allowed to cure under this pressure. It is very important that there are no voids within the resin, in either the inner or outer structural layers, after the resin has cured. Voids, which are basically air pockets, may be present in the resin before curing, and are removed by putting pressure on the beam as the resin cures. Voids are very undesirable since they weaken the beam and can also allow water to intrude into the beam. If water intrudes into the beam, the beam becomes a much better conductor of electricity, thereby making it unsafe in the event of coming in contact with hydro wires.
After curing, the entire assembly is removed from the mold and the mandrel is removed from the beam by pulling it out longitudinally from the beam.
FIGS. 12 and 13 show alternative embodiments of the invention, in which the first, second, third and fourth plates are shown to have a slightly different configuration than the preferred embodiment.
In FIG. 12, portions of the sides 90 of the first plate 82 are in intimate contact with one edge 92 of each of third and fourth plates 86, 88. Similarly, portions of the side 94 of the second plate 84 are in intimate contact with the opposite edges 96 of the third and fourth plates 86, 88.
In FIG. 13, a portion of the sides 112, 114, 116 and 118 of each of the plates 102, 104, 106 and 108 is in intimate contact with the edges 128, 126, 122 and 124 correspondingly of an adjacent plate.
Reference is now made to FIG. 14 which shows an alternative embodiment of the beam 140, having an inner structural layer 142 that is circular in cross-section. The inner structural layer 142 comprises a continuous filament wound in layers of continuous roving along the length of the beam 140, and defines a cylindrical hollow core 143. The middle structural layer 148 comprises a first plate 144 and a second plate 146 which are pre-molded and composed of a cured resin material having a fibre roving with the fibres being generally unidirectional and substantially aligned lengthwise along the plates. These two plates are generally "c"-shaped and have rounded inner surfaces so as to conform to the circular shape of the inner structural layer 142. The first plate 144 has edges 150 and 152 that are in intimate contact with corresponding edges 154 and 156 of the second plate 146. Around the outside of the middle structural layer 148 is the outer structural layer 149, which is the same configuration as the outer structural layer as described in the preferred embodiment.
In a further alternative embodiment, it is possible to make the plates 32, 34, 36 and 38 tapered such that they are thicker at one end of the beam and thinner at the other. This allows for the larger stresses typically found at the fixed end of the beam to be properly accommodated while the other end of the beam is lighter in weight yet sufficient strong to accommodate the lower stresses typically found in that part of the beam.
It is also contemplated that the beam of the present invention could be used as a lamp standard, or indeed in many other ways.
Other modifications and alterations may be used in the design and manufacture of the beam of the present invention without departing from the spirit and scope of the accompanying claims. | A composite beam having high compressive and tensile strength is disclosed. The beam is also very lightweight, has a high modulus of elasticity, and is able to support heavy loads in applications such as in use in aerial lift devices. High dielectric resistance is also a very important property exhibited by the beam. There are three structural layers in the beam including an inner layer comprising a wound filament, a middle layer comprising a plurality of plates, and an outer layer also comprising a woven or a non-woven material. | 4 |
BACKGROUND OF THE INVENTION
2. Field of the Invention
The invention pertains to systems for disinfecting condensation and moisture producing apparatus within air handling systems by the periodic exposure of the apparatus to an anti-microbial gas.
Apparatus producing condensation moisture within air handling systems is subject to contamination by the growth of microorganisms existing on the moist surfaces of the apparatus. Such situations occur in air conditioners, dehumidifiers and other air cooling systems wherein air passing through heat exchanging coils is rapidly cooled and the moisture within the air condenses on the coils and falls into a drip pan or other apparatus for removing moisture.
Microbial growth is common on surfaces where moisture, minerals and organic substances are present, and the growth of such microorganisms on condensing apparatus surfaces reduces the heat exchange efficiency and the overall performance of the apparatus. Additionally, microbial growth produces microorganisms which can become airborne during the operation of the air handling system, therein contaminating ducts and occupied spaces. Such contamination of indoor air has been widely documented, and is a major cause of illness among individuals within office buildings and the like having sealed windows wherein air circulation is only through central cooling and heating units. Contaminated air conditioning systems are known to cause "sick building syndrome", Legionnaire's disease, and hypersensitivity pneumonitis.
The problem of contamination of air handling systems such as those used in commercial buildings, private dwellings and vehicles is particularly acute in warm climate areas that require lengthy air conditioner operation without the opportunity to permit the moisture producing coils, drip pans, and the like to dry. In an effort to control contamination of air handling systems by microbial growth on condensation apparatus, various techniques have been employed. For instance, condensation collecting drip pans are designed to remove the majority of moisture as quickly as possible from the air handling system, but residual moisture will remain. Further, it is recommended that the condensation producing apparatus of air cooling equipment be regularly manually cleaned and disinfected. However, such regular and routine maintenance is often overlooked, and the use of conventional disinfecting techniques creates problems because of the dissipation of disinfectants into the air flowing through the system. Accordingly, air cooling systems are not usually regularly maintained and cleaned to avoid the microbial contamination which occurs and many occupants of buildings and vehicles having contaminated air systems are subject to allergies and illnesses difficult to trace and diagnose.
2.
Description of Related Art
The aforementioned problems with respect to microbial growth within air handling systems has long been recognized, but has not been effectively solved. It is known that the treatment of air within air handling systems by ultraviolet light frequencies can be helpful in controlling microbial growth, and apparatus for doing so is shown in U.S. Pat. Nos. 2,628,083 and 3,100,679. Likewise, an ultraviolet device is shown in U.S. Pat. No. 4,990,313 which would be suitable for use with domestic air cooling systems.
Ozone is known as a strong oxidant and an effective sterilant, and has been used to purify or sterilize refrigerated air, as shown in U.S. Pat. Nos. 2,248,713 and 3,421,836.
While the aforementioned patents propose to deal with the problem of the microbial contamination of air cooling systems, ultraviolet light devices have not proven effective to sufficiently sterilize the air and surfaces within air handling systems to control microbial growth, and while those systems using ozone more readily disinfect inaccessible surfaces than can be achieved with the ultraviolet systems, the exposure of humans to ozone is considered detrimental.
OBJECTS OF THE INVENTION
It is an object of the invention to provide a method and apparatus for controlling microbial growth on condensation coil apparatus which is inexpensive, practical, may be utilized with air handling systems, and may be automatically operated without attention by the user.
Another object of the invention is to provide a method and apparatus for controlling microbial growth on condensation apparatus within air handling systems wherein a strong anti-microbial disinfectant is periodically applied to the apparatus surfaces upon which microorganisms may grow, and yet, the disinfectant is removed from the air handling system prior to restoration of the system to its normal operating cycle to prevent contamination of the system with the disinfectant.
Yet another object of the invention is to provide a method and apparatus for controlling microbial growth on the condensation apparatus of air handling systems wherein a strong disinfectant gas such as ozone may be temporarily introduced into the air handling system at the location of the condensation producing apparatus to treat the apparatus, and the ozone is then removed from the system prior to normal operation thereof.
SUMMARY OF THE INVENTION
In the practice of the invention an air handling system, such as an air conditioning or air cooling system, includes a chamber defined therein through which the air flows as produced by a primary air mover, such as a fan or blower. Moisture condensing apparatus, such as a heat exchanging coil, or the like, is located within the chamber wherein the temperature of air flowing therethrough is reduced. Such a reduction in air temperature will cause condensation of water vapor within the air and this condensate quickly accumulates on the cooling coils and usually falls to a drip pan located below the coil and drained away. However, due to residual moisture and the long periods of time that moisture exists on the condensation apparatus within the chamber microbial growth on such moist surfaces will occur creating the aforementioned problems.
With the invention, provision is made to temporarily terminate air flow through the air handling or cooling system, even during a cooling cycle, wherein the primary air mover, such as the air conditioner blower, is temporarily deenergized. Upon air flow through the chamber and condensing coil terminating, the chamber is sealed with respect to the remainder of the air handling system by baffles or valves. After the chamber is sealed from the air handling system an auxiliary air flow is introduced into the sealed chamber to produce an air flow through the condensing coil and over all of the apparatus within the chamber.
The auxiliary air flow is exhausted exteriorally of the air handling system, and the auxiliary air flow is used to carry a disinfectant, such as ozone, through the chamber for disinfecting and sterilizing the surfaces of the condensation apparatus, such as the heat exchanging coil, drip pan, and the like.
The ozone may be generated by an ozone generator located directly within the source for producing the auxiliary air flow through the chamber, and the auxiliary air flow is maintained for a duration of time sufficient to treat and sterilize the condensation apparatus located within the chamber. After a predetermined time of exposure of the ozone to the chamber, the ozone generation is terminated, and the auxiliary air flow through the chamber is continued until all of the ozone has been exhausted from the chamber. Thereafter, the air handling system primary air blower is re-energized and the cooling cycle continued as air flows through the chamber and cool condensation producing coil.
In the practice of the invention, sufficient disinfecting of the condensation producing apparatus can be achieved by spacing timed disinfecting cycles through a twenty-four hour air cooling operation in a manner that the time that the air cooling system will be deenergized for air cooling purposes is insufficient as to adversely affect the air cooling system in a noticeable manner.
Preferably, the sealing of the chamber and the exhausting of the chamber is accomplished by structure which is of simple fabrication, and yet is foolproof and dependable in operation. For instance, the sealing of the chamber with respect to the adjacent portions of the air handling system may be accomplished by pivoted baffles or vanes located within the air handling system ducts. By pivoting the baffles at their upper edges the weight of the baffles will cause the baffle to hang downwardly due to gravitational forces and thereby seal the duct and prevent air flow from the air handling system into the chamber. However, upon energizing of the primary air mover the air mover is of sufficient capacity and power to cause the baffles to swing to an open condition to permit air flow through the air handling system and chamber. However, the capacity and power of the auxiliary air mover system used during disinfecting of the condensation producing apparatus is insufficient to displace the gravity closed baffles, and the baffles will effectively seal the chamber with respect to the remainder of the air handling system during the disinfecting and sterilizing cycle.
Likewise, an air pressure sensitive exhausting system is used to exhaust the auxiliary air flow and ozone from the chamber during the disinfecting cycle in order to remove the ozone from the primary air handlung system. In this respect, the exhausting apparatus includes a valve which will be shifted to a closed condition during normal operation of the air handling system due to the greater air pressure within the system. However, upon deenergizing of the primary air mover the exhausting apparatus valve will, under gravitational forces, open and establish communication between the chamber and an ozone filter exterior or the air handling system to permit the air and ozone moved by the auxiliary air blower to be removed from the air handling system prior to energizing of the primary air mover.
The operation of the primary and auxiliary air movers, as well as the operation of the ozone generator, is determined by timers and conventional electrical control apparatus, and the operation of the method and apparatus of the invention can be automatically controlled without requiring attention by the user.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned objects and advantages of the invention will be appreciated from the following description and accompanying drawings wherein:
FIG. 1 is a schematic side elevational sectional view taken along Section 1--1 of FIG. 2 of an air handling system in accord with the invention illustrating the position of the components during normal operation,
FIG. 2 is a schematic plan view of the apparatus of FIG. 1 as taken along Section 2--2 of FIG. 1, and illustrating the auxiliary air flow apparatus,
FIG. 3 is an elevational, schematic, sectional view similar to FIG. 1, illustrating the components in the positions occurring during the disinfecting and sterilization cycle as produced by the auxiliary air mover,
FIG. 4 is a sectional, schematic top plan view of the auxiliary air flow apparatus and controls,
FIG. 5 is an enlarged, elevational, diametrical view of the chamber exhaust conduit, illustrating the ball valve in the closed condition, and
FIG. 6 is an elevational sectional view similar to FIG. 5 illustrating the ball valve in the chamber open or exhausting position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIGS. 1--4 the air system 10 is illustrated in a generally schematic manner. In the illustrated version of the air system 10, the system includes an upper pressurized duct 12, a lower return air duct 14, and both of the ducts are in communication with a chamber 16. A heat exchanging coil 18, such as the evaporator coil of an air conditioning system, is located within the duct 16 and the coil 18 is connected to a refrigeration circuit, not shown, whereby refrigerant evaporating within the coil 18 cools the air flowing through the ducts 12 and 14 and chamber 16 condensing moisture upon the coil. A base 20, which may be in the form of a drip pan, is located below the coil 18 receiving moisture condensing thereon, and the base drip pan 20 normally includes a drain, not shown, whereby the majority of the moisture condensed upon coil 18 is drained away.
In FIGS. 1-3 the ducts 12 and 14 are illustrated in a parallel adjacent manner to each other, and the normal direction of air flow therethrough is indicated by the arrows, FIG. 1. It is also to be appreciated that the ducts 12 and 14 could be in opposed alignment each entering the chamber 16 from opposite directions. The particular arrangement of the chamber 16 to its associated ducts forms no part of the invention, but it is to be appreciated that all of the air flowing through the air system 10 will pass through the chamber 16 and the coil 18.
Air movement through the air system 10 is produced by the primary air mover 22 which comprises the typical squirrel cage fan or blower usually used with air conditioning systems. In the disclosed embodiment the primary air mover fan 22 is located within the chamber 16, but it is possible to locate the primary air mover elsewhere, such as in the return air duct 14, as is often the case.
A baffle 24 is located within the upper duct 12 and is pivotably mounted at its upper edge at 26. The baffle 24 is of sufficient vertical height as to seal the duct 12 when, under gravitational force, the baffle 24 is vertically oriented and engages the stop 28, FIG. 3.
In a similar manner, a baffle 30 is located within lower duct 14 and is pivotably mounted at its upper edge at 32, and when vertically oriented under gravitational forces the baffle 30 will engage the stop 34, as shown in FIG. 3.
The purpose of the baffles 24 and 30 is to seal the chamber 16 with respect to the remainder of the air system 10 when the baffles are vertically oriented as shown in FIG. 3. When the primary air mover 22 is energized, as shown in FIG. 1, the power and capacity of the air mover 22 is sufficient to pivot the baffles 24 and 30 to their normal or open conditions as shown in FIG. 1. However, upon the primary air mover 22 being deenergized the baffles 24 and 30 will due to their weight, pivot to the positions shown in FIG. 3.
For purpose of description the portion of the duct 12 between the baffle 24 and the chamber 16 is designated as the outlet 35 of the chamber 16, while the portion of the duct 14 between the baffle 30 and the chamber 16 is designated as the chamber inlet 37.
A hole 36 is formed in the duct 14 within the chamber inlet 37, for a purpose later described, and the chamber exhaust system 38 communicates with the chamber outlet 35.
The chamber exhaust system 38 includes an upper conduit 40 which includes a neck 42 communicating with an ozone filter 44 which contains activated charcoal and discharges into the atmosphere. The duct 12 is provided with a hole 46 through which the conduit 40 extends, and the portion of the exhaust 38 within the chamber outlet 35 includes an oblique conduit portion 48 disposed at approximately 45° to the horizontal.
The lower end of the portion 48 includes an annular ring 50 having a central port 52, and the portion 48 also includes an annular ring 54 inwardly spaced from ring 50 which defines a central port 55, FIG. 6. A lightweight spherical ball 58 of a diameter slightly less than the bore of the portion 48 is freely movable within the bore portion 48 between the rings 50 and 54 as will be appreciated from FIGS. 5 and 6.
The apparatus includes a control box 60 located exteriorly of the air system 10 and an auxiliary air mover fan 62 is located within box 60. The auxiliary air mover 62 may comprise a small squirrel cage blower fan having an outlet conduit at 64 which communicates with the manifold 66. The manifold 66 includes an outlet conduit 68 which extends through the hole 36 formed in the duct 14. In this manner the outlet conduit 68 communicates with the chamber inlet 37.
An ozone generator 70 is located within the manifold 66, and the ozone generator 70 may consist of either a high voltage discharge system or an ozone generating ultraviolet light system as known within the art. The manner in which the ozone is generated does not constitute an aspect of the instant invention.
The box 60 also includes an air conditioner control 76 which in conjunction with a timed relay 72 controls operation of the primary air mover 22 and the refrigeration compressor, not shown, as well as controlling the blower control 78 for the auxiliary air mover 62. A timer 74, electrically connected to the controls 76, 78 and 72 controls the timing of the cycles of the apparatus, as later described.
Under normal operating conditions calling for cool air, the control 76 will be operated by a thermostat, not shown, and as long as cool air is required the refrigeration circuit compressor will be energized to provide refrigerant to the coil 18. Simultaneously, the primary air mover 22 will be in operation, and the flow of air through the system 10 will be as indicated by the arrows in FIG. 1. Duct 12 functions as the outlet for the cool air, the duct 14 constitutes a return air duct, and the air flow produced by the primary air mover 22 will maintain the baffles 24 and 30 in their open conditions as shown in FIG. 1.
Because of the size and capacity of the primary air mover 22, the air velocity and air pressure within the chamber outlet 35 will be at its maximum, which will force the lightweight ball valve 58 against the ring 54 as shown in FIGS. 1 and 5, and as engagement of the ball 58 with the ring 54 seals the port 55, no cooled air enters the exhaust system 38, and the exhaust system 38 is automatically closed when the primary air mover 22 is energized.
Upon the passing of a predetermined timed interval as determined by timer 74, the refrigeration compressor and primary air mover 22 are deenergized, and the deenergization of primary air mover 22 permits the baffles 24 and 30 to pivot to their closed positions as shown in FIG. 3 sealing the chamber 16 and its outlet 35 and inlet 37 from the remainder of the air system 10.
Under the control of timer 74, the auxiliary air mover 62 is now energized along with the energizing of the ozone generator 70. This action causes an auxiliary air flow from air mover 62 into the chamber inlet 37 through conduit 68. As the auxiliary air flow path from air mover 62 includes ozone generator 70 the air flowing into the chamber inlet 37 contains ozone.
Upon deenergizing of the primary air mover 22 the pressure forces acting upon the exhaust ball valve 58 terminate, and the weight of the ball 58 permits the ball to roll to the lower position shown in FIG. 6 wherein the ball 58 engages ring 50 and seals port 52. Positioning of the ball 58 against the ring 50 establishes communication between the plurality of orifices 56 defined in the exhaust portion 48 with the conduit 40 and ozone filter 44. Thus, when the primary air mover 22 is deenergized the exhaust system 38 automatically communicates with the chamber outlet 35.
As the auxiliary air mover 62 forces the ozone laden air into the chamber inlet 37 the anti-microbial ozone-air gas mixture cannot pass into the duct 14 since the baffle 30 is closed and in engagement with the stop 34, FIG. 3. Accordingly, the ozone laden air forced into the chamber inlet 37 will pass into the chamber 16 and the moist coil 18 and drip pan 20 will be exposed to the ozone being forced into the chamber 16. The ozone laden air passing through the coil 18 enters the chamber outlet 35 and the exhaust system orifices 56 and passes through the ozone filter 44 into the atmosphere exteriorly of the air system 10. The ozone will not enter duct 12 as the baffle 24 is engaging stop 28, FIG. 3, and sealing the duct 12 from outlet 35.
When the auxiliary air mover 62 is energized it is to be appreciated that the air pressure produced in chamber 16 is substantially less than that produced by the primary air mover 22, and the weight of baffle 24 and the ball valve 58 is sufficient to prevent displacement by the auxiliary air flow during the disinfecting cycle.
As determined by timer 74, the auxiliary air mover 62 and ozone generator 70 will operate for approximately ten minutes. The ozone generator operation is terminated prior to the termination of the auxiliary air mover 62 in order that the auxiliary air mover may purge all of the ozone from the chamber 16 and its outlet 35 and inlet 37 prior to restoration of the normal operation of the air system 10. After the ozone has been purged from the chamber and its outlet and inlet, the timer 74 will deactivate the auxiliary air mover 62, and energize the refrigeration circuit compressor and primary air mover 22 to restore the air system 10 to its normal air cooling operation. Once the primary air mover 22 is energized the baffles 24 and 30 will automatically open as shown in FIG. 1, and the pressure on ball 58 through port 52 will displace ball 58 inwardly and the ball 58 will engage the ring 54 to seal the exhaust 38 from the atmosphere.
Approximately every eight hours of operation of the air system 10, the aforementioned disinfecting and sanitizing cycle will be energized for about ten minutes. As the ozone entering the chamber 16 will be exposed to any microorganisms within the chamber, within the outlet 35 or chamber inlet 37, or on the base and drip pan 20, the ozone will kill such microorganisms and prevent their growth. As the baffles 24 and 30 are gravity operated, as is the exhaust ball valve 58 the disinfecting and sanitizing cycle of the apparatus will be dependable and automatic, and the practice of the invention will prevent the growth of organisms in air handling systems.
It is to be appreciated that the apparatus described may be retrofitted into existing air cooling systems upon the installation of baffles 24 and 30, exhaust system 38, and the apparatus for introducing ozone into the chamber. It is within the scope of the invention to use other gaseous disinfectants than ozone, and the sealing of the coil chamber and construction of the exhaust system may vary from that disclosed, and other modifications to the inventive concepts may be apparent to those skilled in the art without departing from the spirit and scope of the invention. | The disclosure pertains to a method and apparatus for controlling microbial growth in air handling systems employing heat exchanging coils, water pans, or the like, exposed to moisture and subject to microbial contamination. Condensation apparatus located within a chamber defined in an air handling system is disinfected by temporarily interrupting normal air flow, sealing the chamber with respect to the air handling system, introducing an anti-microbial growth gaseous disinfectant into the chamber, removing the anti-microbial gas from the chamber after disinfecting the condensation apparatus and then restoring normal air flow through the chamber. The preferred anti-microbial gas is produced by using an ozone generator in conjunction with an auxiliary air flow system. | 0 |
TECHNICAL FIELD
The present disclosure relates to ink-jet printing, particularly involving phase-change inks printing on a substantially continuous web.
BACKGROUND
Ink jet printing involves ejecting ink droplets from orifices in a print head onto a receiving surface to form an image. The image is made up of a grid-like pattern of potential drop locations, commonly referred to as pixels. The resolution of the image is expressed by the number of ink drops or dots per inch (dpi), with common resolutions being 300 dpi and 600 dpi.
Ink-jet printing systems commonly utilize either a direct printing or offset printing architecture. In a typical direct printing system, ink is ejected from jets in the print head directly onto the final receiving web. In an offset printing system, the image is formed on an intermediate transfer surface and subsequently transferred to the final receiving web. The intermediate transfer surface may take the form of a liquid layer that is applied to a support surface, such as a drum. The print head jets the ink onto the intermediate transfer surface to form an ink image thereon. Once the ink image has been fully deposited, the final receiving web is then brought into contact with the intermediate transfer surface and the ink image is transferred to the final receiving web.
FIG. 1 provides a simplified view of a direct-to-sheet, continuous-media, phase-change ink printing machine. A media supply and handling system is configured to supply a long (i.e., substantially continuous) web of media W of “substrate” (paper, plastic, or other printable material) from a media source, such as spool of media 10 . In certain printing machines the web W passes through a series of tensioning rollers 12 to a pre-heater 18 that brings the web to an initial predetermined temperature that is selected for desired image characteristics corresponding to the type of media being printed as well as the type, colors, and number of inks being used. The media is then transported through a printing station 20 that includes a series of print head modules 21 A, 21 B, 21 C, and 21 D, each printhead module effectively extending across the width of the media and being able to place ink directly (i.e., without use of an intermediate or offset member) onto the moving media. As is generally familiar, each of the print heads may eject a single color of ink, one for each of the colors typically used in color printing, namely, cyan, magenta, yellow, and black (CMYK). Image data obtained from an image processor, such as a scanner (not shown) is provided to a controller 22 that controls the operation of the print heads as well as the delivery of molten ink from the ink supply 24 to the print heads.
Following the printing zone 20 along the media path are one or more “mid-heaters” 30 that may use contact, radiant, conductive, and/or convective heat to control a temperature of the media. The mid-heater 30 brings the ink placed on the media to a temperature suitable for desired properties when the ink on the media is sent through the fixing assembly 40 . The fixing assembly 40 is configured to apply heat and/or pressure to the media to fix the images to the media. The fixing assembly may include any suitable device or apparatus for fixing images to the media such as an image-side roller 42 and a pressure roller 44 , both configured to apply heat and pressure to the media. Nip rollers 50 are provided at the outlet of the fixing assembly to guide the substrate to a receiving station (not shown).
The printing machine may use “phase-change ink,” by which is meant that the ink is substantially solid at room temperature and substantially liquid when heated to a phase change ink melting temperature for jetting onto the imaging receiving surface. The phase change ink melting temperature may be at any temperature that is capable of melting solid phase change ink into liquid or molten form. In certain printing machines, the phase change ink melting temperature is approximately 70° C. to 140° C. The molten ink supply 24 for a phase-change ink system thus includes a melting station having a melter 25 that melts solid ink elements received from a hopper 26 . In certain embodiments the solid ink elements are in the form of pellets that are fed from a solid ink supply 27 through a feed conduit 28 to the hopper. The supply 27 is replenishable, meaning that it can be re-filled with solid ink pellets or replaced with a fully loaded supply container.
High usage or throughput printing systems typically require large solid ink supplies 27 that do not require frequent replenishment. Thus, in such high throughput systems the supply is in the form of one or more large drums, such as a 55 gallon drum. A solid ink supply of this magnitude can accommodate high ink usage rates (on the order of 33 gallons per color per day) without placing an undue burden on the operator to constantly replace or replenish the solid ink supply.
SUMMARY
In one aspect of the disclosure a printing machine is provided comprising a substrate supply station, a molten ink supply, a printing station operable to receive a substrate from the substrate supply station and molten ink from the molten ink supply and apply the molten ink onto the substrate, and a fixing assembly for fixing the molten ink onto the substrate. The molten ink supply may comprise a container for storing solid ink pellets, a withdrawal tube having an inlet end disposed within the container and an outlet end, a vacuum generator at the outlet end of the withdrawal tube operable to draw a vacuum within the withdrawal tube, a feed conduit connected to the outlet end of the withdrawal tube for receiving solid ink pellets drawn therein by the vacuum generator, and a melter station receiving solid ink pellets from the feed conduit and operable to melt the solid ink pellets.
In a further aspect, the molten ink supply further comprises an assist tube connectable at one end to a source of pressurized gas and having a discharge nozzle at an opposite end positioned within the withdrawal tube at the inlet end. The discharge end is configured to direct a flow of gas effective to agitate solid ink pellets within the withdrawal tube.
In another feature, an apparatus is provided for feeding solid ink pellets from a container to a melter in a solid ink printing machine that comprises a withdrawal tube having an inlet end disposed within the container and an outlet end, a vacuum generator at the outlet end of the withdrawal tube operable to draw a vacuum flow within the withdrawal tube, and a feed conduit connected at one end to the outlet end of the withdrawal tube for receiving solid ink pellets drawn therein by the vacuum generator, and connectable at an opposite end to the melter. An assist tube may be provided that is connectable at one end to a source of pressurized gas and having a discharge nozzle at an opposite end positioned within the withdrawal tube at the inlet end. The discharge end is configured to direct a flow of gas effective to agitate solid ink pellets within the withdrawal tube.
A method may be further provided for supplying solid ink pellets from a container to a melting station in a solid ink printing machine that comprises introducing the inlet end of a withdrawal tube into a container of solid ink pellets, generating a vacuum at the outlet end of the withdrawal tube to draw a vacuum flow within the withdrawal tube sufficient to pull solid ink pellets through the withdrawal tube, and providing air flow through a feed conduit connected to the outlet end of the withdrawal tube sufficient to push the solid ink pellets through the conduit to the melting station connected thereto. The method may further comprise introducing a separate air flow within the withdrawal tube at the inlet end thereof, the separate air flow sufficient to agitate solid ink pellets contained within the withdrawal tube.
DESCRIPTION OF THE FIGURES
FIG. 1 is a representation of the components of a printing machine using phase-change ink.
FIG. 2 is cut-away view of a solid ink supply disclosed herein.
FIG. 3 is an enlarged partial cross-sectional view of the solid ink supply shown in FIG. 2 .
DETAILED DESCRIPTION
Referring to FIGS. 2-3 the solid ink supply 27 is shown in the form of a drum or other container with a supply of pellets P disposed therein. A pellet feed apparatus 60 is provided that is operable to withdraw pellets from the supply container 27 and feed the pellets through the feed conduit 28 to the hopper 26 ( FIG. 1 ). In one aspect, the pellet feed apparatus 60 includes a withdrawal tube 62 that extends into the supply container 27 with its inlet end 63 on or near the base of the supply container. A vacuum generator 64 is provided at the discharge end 65 of the withdrawal tube. The vacuum generator is operable to draw a vacuum V in the withdrawal tube 62 that is sufficient to pull the solid ink pellets P upward through the tube and to the feed conduit 28 . The vacuum generator may be a venturi type device that utilizes pressurized gas from a source S. The pressurized gas source S may be a pressurized air source of the printing machine used to perform other functions of the machine.
Referring to FIG. 3 , the inlet end 63 of the withdrawal tube 62 is provided with a series of openings 68 that are sized for passage of one or more pellets P. It can be appreciated that when the withdrawal tube is introduced into the supply container 27 a certain amount of pellets will spill through the openings 68 into the withdrawal tube. When the vacuum generator 64 is operated, the suction force V will draw those pellets upward and will also pull pellets from the supply container 27 through the openings 68 and into the withdrawal tube 62 . Since the inlet end 63 is positioned near the bottom of the container gravity will continually direct the pellets downward and into the openings 68 as the pellets within the withdrawal tube 62 are moved upward. The openings 68 are formed in the side wall 62 a of the withdrawal tube 62 and are arranged at a height above the base of the container so that during operation pellets entering the openings can be more readily pulled upward by the suction force V.
For certain solid ink pellets and supply container configurations the withdrawal tube 62 may have an inner diameter of about 25 mm (one inch) to accommodate pellets that are generally spherical with a diameter of about of 1 mm (0.04 inch). The openings 68 may have an effective diameter of about 3-5 mm (0.12-0.20 inch) so that the pellets may flow freely therethrough. In some cases the pellet diameters may range from 0.43-1.03 mm for color pellets and 1.0-9.0 mm for clear pellets. The openings 68 may thus be sized to readily accept these pellets, in some cases ranging from 9.5 to 12.5 mm in diameter. In one embodiment, the openings may have an effective diameter that is between about 1.3 and 5 times the diameter of the pellets.
The vacuum generator 64 provides an efficient method for withdrawing solid ink pellets from the supply container 27 and transporting the pellets through the feed conduit 28 to the hopper. However, certain difficulties arise with smaller pellet diameters. In particular, the smaller pellets bunch tightly together within the supply container 27 , which inherently restricts air flow through the pellets in the container. Air flow through the pellets is necessary for the generation of the vacuum force V. While larger pellets permit adequate air flow through the mound of pellets within the container, the larger size of the pellets makes them heavier and harder to draw up through the tube without significantly increasing the vacuum produced by the vacuum generator 64 . Moreover, larger pellets may present design issues with respect to the hopper 26 and melter 25 of the molten ink supply 24 ( FIG. 1 ).
In order to address the air flow concerns associated with smaller pellet diameters, the pellet feed apparatus 60 may include an assist tube 70 that receives pressurized air from the source S. The assist tube 70 extends along the withdrawal tube 62 and includes an arm 74 that extends into the interior of the withdrawal tube at the inlet end 63 of the tube. The withdrawal tube 62 may be provided with an opening 72 through which the arm 74 of the assist tube extends. The opening 72 may be sized to fit tightly around the assist tube arm 74 to prevent pellets from becoming lodged therein.
The assist tube 70 includes a discharge nozzle 75 that is directed at least partially upward along the length of the withdrawal tube. Pressurized air fed from the source S to the assist tube thus provides a flow of air F from the discharge nozzle 75 that helps dislodge and agitate pellets that may accumulate at the bottom of the withdrawal tube. The air flow F also provides adequate background air flow to allow the vacuum generator 64 to operate consistently without any significant variation in pellet feed rates through the pellet feed apparatus 60 .
The assist tube 70 may be provided with different discharge nozzle 75 configurations. For instance, the assist tube may include multiple arms 74 and associated discharge nozzles that are oriented in proximity to each pellet feed opening 68 in the withdrawal tube 62 . The discharge nozzle or nozzles may be arranged at different orientations within the withdrawal tube, rather than the vertical orientation shown in FIG. 3 . The nozzle(s) may also be configured to provide a wider or narrow flow pattern F. The discharge nozzle 75 may be configured to be below the height of the openings 68 so that the air flow impinges on pellets as they enter the openings. In another embodiment, the arm 74 may be sized and configured to span the base 62 b of the container and may be provided with a plurality of upwardly directed openings serving as discharge nozzles 75 .
In a specific example, the pellet supply container 27 is a 55 gallon drum storing pellets having a diameter of about 1 mm. The withdrawal tube 62 has a diameter of about 25 mm with the vacuum V being pulled by a 10 psi air supply to the vacuum generator 64 . The assist tube in this example may have a diameter of about 9 mm (0.38 inch). Air is provided to the assist tube 70 at about 7 psi. With this configuration the pellet feed apparatus 60 is capable of delivering solid ink pellets at a rate of about 218 grams per minute with substantially uniform, uninterrupted flow.
The withdrawal tube and assist tube may be formed of metal, plastic or other material suitable for continuous contact with solid-ink pellets and capable of sustaining continuous air flow therethrough. The vacuum generator may be an in-line venturi device, or other suitable device capable of generating a vacuum flow sufficient to transport solid ink pellets and a discharge flow sufficient to propel the pellets through the feed conduit. The vacuum generator and assist tube may be connected to a common air pressure source that is part of the printing machine, external to the machine or part of the pellet supply system. A regulator may be provided to regulate the air pressure provided to each component. The venturi device and assist tube may operate with a gas other than air that is inert to the solid ink pellets. Sensors may be provided to automatically stop air flow to the components when the pellet supply is empty.
In the illustrated embodiment, the assist tube 70 is separate from and exterior to the withdrawal tube 62 . However, the assist tube may be associated with the withdrawal tube in other ways. For instance, the assist tube may be attached to the inside of the withdrawal tube, or the assist and withdrawal tubes may be integrally formed. Moreover, the withdrawal tube is shown with a bottom wall 62 b at the inlet end 63 , which can help maintain the vacuum flow within the discharge tube. Alternatively, the inlet end of the withdrawal tube may be open with the tube configured to be engaged within the container 27 with the open inlet end 63 bearing against the base of the container in sealed engagement.
It is contemplated that the pellet feed apparatus 60 may be integrated into the printing machine and arranged to be inserted into a new ink supply container. Alternatively, the pellet feed apparatus may be integrated into the ink supply container or associated with a removable lid or cover for a re-fillable container. The pellet feed apparatus 60 may be provided with appropriate fittings on the venturi vacuum generator 64 , withdrawal tube 62 and/or assist tube 70 for simple and quick connection to the printing machine. For printing machines that already include a vacuum or suction element, the venturi vacuum generator 64 may be eliminated from the apparatus 60 and the withdrawal tube 62 provided with a fitting to engage the existing suction element of the printing machine.
It will be appreciated that various of the above-described features and functions, as well as other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. | A molten ink supply for a solid ink printing machine includes a container for storing solid ink pellets and a withdrawal tube having an inlet end disposed within the container. A vacuum generator is disposed at the outlet end of the withdrawal tube operable to draw a vacuum within the tube. A feed conduit is connected to the outlet end for receiving solid ink pellets drawn therein by said vacuum generator and conveying the pellets to a melting station operable to melt the solid ink pellets. An assist tube is provided within the container with a discharge nozzle disposed within the withdrawal tube at the inlet end and operable to provide a flow of air into the withdrawal tube to agitate solid ink pellets and facilitate withdrawal of the pellets by the vacuum generator. | 1 |
TECHNICAL FIELD
[0001] The present invention involves a cooling system and method for its operation used for cooling devices in a data center. Data centers are rooms that contain electronic systems generally arranged on racks, the standard rack being defined by the EIA as an enclosure approximately 78″ high, 24″ wide and 40″ deep. These racks are employed to house printed circuit board-based devices which, under normal operation, can generate significant amounts of heat. For the proper operation of such devices and for maintaining them throughout their normal life cycle, proper temperature and humidity must be maintained.
BACKGROUND OF THE INVENTION
[0002] Historically, computer room air conditioning (CRAC) systems were manufactured by those who supplied residential and commercial air conditioning systems, generally. The design philosophy was to build such systems at the lowest possible cost, that is, the cost of manufacturing being more important than the operational cost of the system. These CRAC systems were built to do as much work as possible while occupying the smallest possible space within the data center. Energy consumption in running these systems was less of a consideration than the floor space that the units would occupy in a typical data center location.
[0003] These design considerations have changed considerably over time as computing systems of the type typically located within a data center consume considerable amounts of energy while generating heat necessitating CRAC systems of greater efficiency. With the increasing popularity of the Internet, data centers are now considered to be the number one energy consumer in the United States.
[0004] There have been three fundamental CRAC system designs referred to, for the sake of simplicity, as CRAC 1 , CRAC 2 and CRAC 3 .
[0005] CRAC 1 is a split refrigeration system with outdoor air cooled condensing. This system is characterized by having two main components, namely, the CRAC unit itself located inside of the data center and a condenser located external thereto. The indoor unit houses the systems' compressors, evaporators, controls and cooling fans. The outdoor unit houses the condenser and condenser fans which inter-connect to the indoor unit with piping through which the refrigerant travels.
[0006] The CRAC 2 system also employs two main components, namely, the CRAC units located within the data center and heat exchanger components located external thereto. The indoor unit houses the compressor, condenser, evaporator, system controls and cooling fans. The outdoor unit is composed of a heat exchanger from which heat from the system is rejected as well as pumps used to move heat transfer fluid from the indoor to outdoor units. This design can also have an optional heat exchanger located in series with the indoor heat exchangers. When the fluid temperature from the outdoor heat exchanger is below the return air temperature, a valve opens allowing the heat transfer fluid to pass through the lead heat exchanger. The fluid removes heat from the return air stream.
[0007] CRAC 3 systems employ CRAC units located in the data center and fluid chillers located external thereto. The indoor unit houses the indoor heat exchanger, indoor fan systems and controls. The outside unit is composed of either a self-contained refrigeration system which chills the heat transfer fluid which is usually air cooled or a split chiller system which is composed of a compressor, evaporator, fluid cooled condenser and fluid cooled heat exchanger.
[0008] Regardless of the system type, the design philosophy in sizing and installing CRAC systems in a data center is quite consistent from installation to installation. The typical installation involves adding a sufficient number of units to meet the anticipated heat load of the facility and one additional unit for redundancy. Thus, as facilities grow, more indoor and outdoor units are added to the system noting that, typically, each CRAC unit operates independently of other units. Thus, the control valves of each unit are turned on and off independently of other units to meet and maintain building loads. Indoor fans never shut off to maintain the load imposed upon the facility. Centrifugal fans are commonly employed for supply side air. Small fans are employed even though smaller fans are generally more inefficient than those which are larger. Regardless of fan type, current CRAC installations are based upon a “one load, one system” methodology. Such installations exhibit the same efficiency when operating under normal or emergency conditions. These systems do not integrate redundancy in the form of additional heat exchange area in order to make them more efficient. Parameters seldom change dramatically unless loads change dramatically. The redundancy of this type of system is based upon adding units which are brought on line as needed.
[0009] It is quite apparent that previously suggested CRAC systems made no attempt to maximize operating efficiencies as most prior designs were created well before energy became as expensive as it is today and before the explosive use of Internet-based communications and information downloading created such a severe impact upon energy usage and resultant heat generation.
[0010] Thus, it is an object of the present invention to provide CRAC systems having several unique and innovative design criteria to make such systems much more efficient to operate while maximizing their ability to effectively cool a data center both under ordinary conditions and when emergencies require supplemental cooling capacity.
[0011] It is yet a further object of the present invention to provide a data center cooling system which, depending upon environmental conditions, can transfer coolant while bypassing the systems' compressor.
[0012] Although the discussion which appears below reveals a unique system capable, under certain conditions, to provide coolant to condenser coils without use of a compressor, the present invention is not the first instance in which compressor-free cooling has been suggested. In this regard, reference is made to FIG. 1 representing a schematic drawing of such a system commercially available from Trane Co. Specifically, when water returning from cooling tower 11 is colder than the chilled water circulating through cooling load 12 , refrigerant pressure within condenser 13 is slightly lower than that in evaporator 14 . This pressure differential drives the refrigerant vapor “boiled off” in evaporator 14 to condenser 13 , where it condenses and flows by gravity back to evaporator 14 . As long as the proper pressure difference exists between evaporator 14 and condenser 13 , refrigerant flow and consequent “free cooling” continues. According to its manufacture, the system shown in FIG. 1 is capable of refrigerant-migration “free cooling” up to as much as 40% of the chiller's design tonnage. Since the chiller and “free cooling” cycle cannot operate simultaneously, free cooling of this type can only be used when the cooling capacity of water tower 11 is sufficient to meet the entire building load. As “free cooling” capacity is available only when the ambient wet bulb temperature is below 50 degrees F., accessories such as chilled water pumps, condenser water pumps and cooling tower fans must continue to operate in their conventional manner while the chiller operates in the “free cooling mode.” This minimizes the energy savings from such a system which is realized only from its ability to bypass its compressor.
SUMMARY OF THE INVENTION
[0013] As a first embodiment, the present invention involves a cooling system for cooling devices housed in a data center, the device comprising a cabinet, a set of evaporator coils, an inlet and outlet and at least one fan for drawing air from within the data center through said cabinet and for movement of the air over said evaporator coils to the data center heat loads. The improvement comprises angling the air flow emanating from the cabinet proximate 45° to 70° to the plane of the flooring.
[0014] As a second embodiment, the invention is directed to a cooling system for cooling a data center to a predetermined temperature and humidity, the cooling system comprising a set of evaporator coils and a fan for moving air within the data center passed the set of evaporator coils. At least two sets of compressors, two sets of condensers and two independent control systems are located external to the data center and positioned in parallel to provide coolant to the set of evaporator coils.
[0015] The third embodiment involves a cooling system comprising a compressor, a condenser, coolant, pump and primary evaporator coil for cooling. The improvement comprises a secondary evaporator coil in series with the primary evaporator coil, the secondary evaporator coil being a flooded coil piped to the condenser.
[0016] As yet another embodiment, the invention involves a cooling system comprising a compressor, condenser, condensable coolant, pump and evaporator coils. The improvement comprises a measurement device and actuator wherein when the measurement device measures the wet-bulb temperature and when it is no greater than a preselected value, the compressible coolant is circulated by the pump between the condenser and evaporator coils while bypassing the compressor.
BRIEF DESCRIPTION OF THE FIGURES
[0017] FIG. 1 is a schematic depiction of a commercially available chiller of the prior art.
[0018] FIG. 2 is a side view of a portion of the present invention showing evaporator coils and fans to be housed in a cabinet used for cooling an appropriate data center according to the present invention.
[0019] FIG. 3 is a schematic view of a system according to the present invention including two circuits provided for redundancy and for increased efficiency.
[0020] FIG. 4 is a schematic view of a part time economizing system using a scavenger coil in series with main evaporator coils to increase efficiency of the present invention.
[0021] FIG. 5 is yet another schematic view of an economizing circuit similar to that depicted in FIG. 3 .
DETAILED DESCRIPTION OF THE INVENTION
[0022] Turning first to FIG. 2 , housing 20 is depicted with its side walls removed for illustrative purposes. Frame members 21 support sets of evaporator coils 22 receiving coolant from compressors and related hardware located external to the data center being cooled.
[0023] In operation, ambient air within the data center is drawn through open top 25 passed sets of evaporator coils 22 through the use of prop or axial fans 23 . Ideally, multiple fans are employed sufficient to maintain a positive static pressure within a space beneath the flooring. Although not shown, cool air created by housing 20 is discharged proximate racks of circuit boards and similar solid state devices through openings strategically located proximate thereto.
[0024] A feature of the present invention is the orientation of fans 23 in directing cooled air in the direction of arrows 24 . CRAC units of the prior art generally employ centrifugal fans that blow air directly at the floor. This increases the static pressure load on the fans as the air is forced to change direction by 90 degrees upon impacting the floor. The present invention employs prop or axial fans 23 directing air discharge as shown by arrows 24 by mounting the fans at a 20 to 45 degree angle from vertical or 45 to 70 degree angle proximate to the plane of the floor. This provides a much improved approach angle of the cold air discharge relative to the floor and reduces the pressure drop characterized by prior systems. All such expedients are considered to be embraced within the present invention. Sufficient fans are employed for maintaining static pressure and air flow within the space noting that output can be varied to maintain the required static pressure via static pressure sensors.
[0025] Yet a further embodiment of the present invention can be appreciated by reference to FIG. 3 . In its basic terms, system 30 is composed of two simple circuits, operating in parallel. Specifically, parallel condensers 31 A and 31 B as well as parallel compressors 34 A and 34 B operate externally to the data center each set operating in conjunction with pumps 35 A and 35 B, respectively, to supply coolant to expansion valves 36 and onto evaporators 32 A/ 32 B and 33 A/ 33 B, located within the data center. Redundant condensers and evaporators are operated together at part load while increasing the heat exchange surface area resulting in a decrease in the temperature differences within the system; that is, the temperature difference between the coolant temperature and the air temperature flowing over the coil. By decreasing this temperature difference, pressures are generally higher on the evaporator side and lower on the condenser side of the system thereby decreasing the compression ratio of the coolant and reducing the energy the compressors consume to compress the coolant gas.
[0026] A main function of the present system is that it allows for reduced compression operation. Compression ratio is a reference to the difference between the suction and the discharge pressures measured in absolute pressure. There are several main reasons why the present invention can accomplish reduced compression where others cannot.
[0027] As background, typical systems compression ratios are derived by the use and control of the condensing pressure. Typical systems control the condensing pressure buy either staging the condenser fans off and on to meet a set point of condensing pressure or speed control fans to meet that specific point. The present system utilizes a unique form of control to allow for reduced compression. Instead of turning fans on and off or slowing them down to meet a specific point, the present system utilizes a variable set point. Ideally, this set point establishes a condensing temperature that is 8 degrees F. higher than the wet bulb temperature. Condensers are controlled to match loads in ton and to match a true constant set point.
[0028] It should be noted that every major compressor manufacturer establishes proper operational conditions for its products. It is common for manufacturers to state that a compression ratio of 1.5 to 1 is the lowest allowable compression ratio as anything less is not warrantable. Increased mass flow rate is the main reason manufacturers do not want lower compression rations. As compression ratios decrease, a machine's capability of pumping refrigerant increases. As an example, at a 2 to 1 compression ratio, a machine may be capable of pumping 50 tons of coolant while at a 1.5 to 1 compression ratio a machine may be capable of pumping 75 tons of coolant and at 1.05 to 1, that same machine may be capable of pumping 100 tons of coolant. As the mass flow rates increase thru the compressor restriction, friction increases as well, as much as double in some cases. This causes a higher amount of wear and tear on machine parts as gas flows thru the compressor ports, pipe and valves.
[0029] The present system commonly operates at compression ratios of 1.05 to 1-1.51 to 1 and in most cases it operates well under a manufacture's published allowable compression ratio for long periods of time. This is done by not exceeding the machine's designed mass flow rate rather than compression ratio. This is achieved by reducing the speed of the compressor to only allow the machine to pump coolant to match its maximum mass flow rate.
[0030] To enable the present system to perform at reduced compression levels, it must be able to compensate for what normal systems cannot do. Low compression ratios create lower flow rates through typical metering devices. Every metering device is rated based on pressure differential across its valve. For example, a common metering device may be rated at 15 tons under common conditions, but as a system's compression ratio or pressure differential drops, that same valve may be only rated for 5 to 10 tons.
[0031] Ideally, metering valves used herein are rated and designed at a 1.3 to 1 compression ratio. These metering valves are provided with a constant pressure differential by amplifying liquid pressure entering the valve with the use of a liquid coolant pump and speed control. Pump speed is varied to maintain a constant pressure drop across the metering devices.
[0032] Yet a further embodiment of the present invention can be appreciated by reference to FIG. 4 . Specifically, system 40 is depicted whereby coolant from pump 42 located externally to the data center urges coolant through a separate evaporator coil 44 which is called a “scavenger coil.” The scavenger coil is located in series with main evaporator coils 43 through which air flows in the direction of arrows 45 for cooling the data center. Vapor condenser 41 is also located externally to the data center to complete the circuit.
[0033] Again referring to FIG. 4 , scavenger coil 44 is a flooded coil that is piped directly back to condenser 41 . When the coolant temperature is lower than the return air temperature, bypass valve 47 opens allowing coolant into the scavenger coil where it removes heat from the data center. The coolant then returns directly back to condenser 41 , via flash vessel 33 without moving through a compressor, thus enhancing system efficiency. As condenser 41 still uses energy to remove heat and pumps use energy to pump coolant, some energy is still employed to operate system 40 . However, energy usage is far more efficient than in a typical vapor compressor cycle.
[0034] As is quite apparent, coolant from the pump goes through an entirely separate cooling coil called the scavenger coil (SC) in series with the main evaporator coils. This SC coil is a flooded coil that is direct piped back to the condenser. When the condensing liquid temperature is lower than the return air temperature a valve opens allowing refrigerant into the scavenger coil where it removes heat and goes directly back to the condenser to extract the heat from the room. If, for example, the return air temperature is 68° F. and the condensing liquid temperature is 65° F., heat from the return air is absorbed into the refrigerant (hot goes to cold). The larger the differential is between the return air temperature and the refrigerant temperature, the more energy is removed with this coil. Since a BTU is a BTU the condensers still use energy to remove the heat and the pumps use energy to pump the refrigerant there still is energy used. This energy usage is far more efficient than a typical vapor compressor cycle.
[0035] To summarize, coolant pump 42 pumps liquid refrigerant to feed devices 49 and into the scavenger coils 44 . Inside the scavenger coils, the liquid refrigerant removes heat while still in a semi liquid form. Liquid refrigerant leaves the scavenger coils and flows to flash vessel 46 . Vapor leaves flash vessel 46 and enters the condenser 41 to be condensed. Flash vessels 46 level is approximately 2 feet below condenser 41 outlet for purposes of maintaining a proper liquid trap. Flash vessel 46 maintains a liquid level based on the weight of the refrigerant and acts as an expansion tank.
[0036] The present system is also designed, under certain conditions, to allow for “free cooling.” This means that the system operates under the physics of a thermo-siphon or through migration cooling as was suggested when discussing FIG. 1 . However, in this instance, when the wet bulb temperature is less than approximately 41-45 degrees F., the “free cooling” cycle operates. Instead of operating with gravity controlling the flow rate as in the prior art, the present system employs a pump to ensure there is enough of a pressure difference to allow the coolant to flow through the metering valve and the evaporator where it is boiled off and routed through a motorized valve to the condenser where it condenses without moving through a compression cycle. If the system detects a lack of movement of the coolant or if a pulse is detected indicating a break in natural migration from the condenser to the evaporator, the compressor is activated by a sensor enabling the system to operate normally.
[0037] To fully appreciate the system architecture of the present invention, as its preferred embodiment, reference is made to FIG. 5 . It is noted that system 50 is, in effect, one system having two circuits. Multiple evaporator coils 51 and 52 are located within the data center to be cooled. A first circuit comprised of compressor 53 , condenser 54 , expansion receiver 55 , pump 56 and metering valves 57 is employed in conjunction with parallel elements comprised of compressor 58 , condenser 59 , expansion receiver 60 , pump 61 and metering valves 62 . Both circuits work together but are capable of working independently in case of system failures or emergencies. Each air handling unit has both circuits operating in parallel comprised of the same components as in any typical refrigeration system. The systems can be expanded to meet growing loads. Indoor and outdoor units can be added as demand or as planned expansion requires. Further, through the use of pumps 56 and 61 together with metering valves 57 and 62 , economizing can be carried out as explained above, by circulating coolant without use of compressors 53 and 58 if outdoor wet bulb temperatures so dictate.
[0038] What was discussed above represents examples of various embodiments of the present invention. It is assumed that other embodiments will be readily apparent to those skilled in the art. It is intended that the specification is to be considered illustrative of the present invention, the scope of which is to be limited only by the claims. | A cooling system and method for cooling devices housed in a data center. A cabinet housing a set of condenser coils is located within the data center positioned on its floor and including fans for drawing air passed the condenser coils and exiting the device angularly to the floor of the data center. The present invention also contemplates the use of redundant compressors and condensers, a system that includes a secondary evaporator coil and configuration which enables the device, under certain conditions, to bypass its compressor. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 13/256,798 filed Sep. 15, 2011, which is the United States national phase of International Application No. PCT/JP2010/053761 filed Mar. 8, 2010, and claims priority to Japanese Patent Application No. JP 2009-063148 filed Mar. 16, 2009, the disclosure of each of which is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to an orally disintegrating tablet that can be produced using dry granulation.
[0004] 2. Background Art
[0005] Orally disintegrating tablets rapidly disintegrate in the oral cavity when they are taken so as to facilitate their ingestion, and therefore are to be particularly preferably prescribed to people who have low swallowing ability, in particular, children, elderly people, and the like, due to their easiness and convenience in ingestion.
[0006] It is necessary that orally disintegrating tablets are maintained in a tablet form stably during from production till packaging, transport, and storage while ensuring that the tablets have the ability to rapidly disintegrate in the oral cavity. Therefore, specifically, the so-called orally disintegrating tablets are usually at least required to disintegrate within 30 seconds in the oral cavity and have a tablet hardness of 40 N or more.
[0007] Embodiments of orally disintegrating tablets known at this time include tablets that will be described below.
[0008] Patent Document 1 discloses an orally disintegrating tablet containing sugar or sugar alcohol having an average particle size of 30 μm to 300 μm. In the Examples in Patent Document 1, orally disintegrating tablets obtained by wet granulation or direct compression are disclosed, and the characteristics of the obtained tablets are also shown in Table 1.
[0009] The orally disintegrating tablets disclosed in Patent Document 1 have inadequate tablet hardness as shown in Table 1. Since the case of a tablet containing a water-labile medicinal substance cannot be produced using wet granulation, then dry granulation or direct compression is used. Dry granulation is mentioned in the specification, but is not specifically recognized in the Examples and the like. Direct compression is disclosed in Examples 13 to 15, however, it takes long time of 38 to 67 seconds to distintegrate in the oral carvity for normal adults, and even more time required can be predicted for disintegration upon ingestion by children or elderly people, which are not preferred.
[0010] As mentioned in, the paragraph (0005), dry granulation can be used as one of the methods for producing a tablet containing a water-labile medicinal substance.
[0011] Patent Document 2 discloses an orally disintegrating tablet produced using dry granulation, with starch and crystalline cellulose and/or powdered cellulose. The orally disintegrating tablet produced using dry granulation is clearly described in a specific manner in Example 3 in Patent Document 2, and it is also described there that the obtained tablet has a hardness of 72 N and a disintegration time of 13 seconds in the oral cavity.
[0012] As mentioned in the paragraph (0006), an orally disintegrating tablet can be produced by dry granulation with crystalline cellulose and/or powdered cellulose to achieve adequately a high hardness and a reduced disintegration time in the oral cavity for the orally disintegrating tablet. However, Non-Patent Document 1 and the like have shown that the tablet with the aforementioned celluloses requires a large amount of water to disintegrate. It can be seen from FIG. 11 of Non-Patent Document 1 that powdered cellulose and low substituted hydroxypropyl cellulose are extremely highly hygroscopic, and such tablets require a large amount of water to disintegrate.
[0013] Meanwhile, orally disintegrating tablets are to be particularly preferably prescribed to children and elderly people, who secrete less saliva in the oral cavity than normal adults, which may cause inadequate disintegration of tablet or difficulty in swallowing. Therefore, there is a demand for formulation of an orally disintegrating tablet that capable of disintegrating with a smaller amount of water.
[0014] Patent Document 3 discloses producing an orally disintegrating tablet with improved mechanical strength by merely previously compounding a small part of sugars serving as an excipient in the tablet with silica and performing mixing. Orally disintegrating tablets produced in such a manner are high in sugar content and can provide a favorable feeling upon ingestion. However, in such a manner, the poor flowability of powders varies the loaded amount of powders in a mill, which is problematic. Moreover, the tablet has adequate hardness but inadequate friability, and there is concern that cracking or chipping may occur during production, packaging, transport, and the like.
PRIOR ART DOCUMENTS
Patent Documents
[0000]
Patent Document 1: Japanese Laid-Open Patent Publication No. 2001-058944
Patent Document 2: Japanese Laid-Open Patent Publication No. 2007-332074
Patent Document 3: Japanese Laid-Open Patent Publication No. 2006-248922
Non-Patent Document
[0000]
Non-Patent Document 1: Yakuzaigaku (Journal of Pharmaceutical Science and Technology, Japan) Vol. 66, No. 6 (2006) 473-481
SUMMARY OF INVENTION
[0019] It is an object of the present invention to provide an orally disintegrating tablet produced by dry granulation and compression, having a hardness of 40 N or more, a disintegration time of 30 seconds or shorter, a friability of 0.1% or less, and an excellent feeling upon ingestion, that is capable of disintegrating with a small amount of water, having a rapid disintegration time, and being maintained stably in a tablet form, which could not be achieved by conventional procedures.
[0020] The inventors of the present invention have conducted in-depth studies and have made it possible to produce a desired orally disintegrating tablet having the following features, which are different from conventional procedures.
[0021] (1) An orally disintegrating tablet produced by dry granulation, which contains a medicinal ingredient with silica, and sugar alcohol or/and sugar.
[0022] (2) The orally disintegrating tablet of (1), wherein the medicinal ingredient is water-labile.
[0023] (3) The orally disintegrating tablet of (1), wherein the sugar alcohol is mannitol, erythritol, xylitol, maltitol, sorbitol.
[0024] (4) The orally disintegrating tablet of (1), wherein the sugar is lactose, sucrose, glucose, trehalose.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Hereinafter, the present invention will now be described in detail.
[0026] “Dry granulation” as used herein is a general term for granulation methods that use no liquid component during granulation.
[0027] Examples of the dry granulation methods that can be used in the present invention include methods employing a roller compactor, a Pharmapaktor, a Chilsonator, a rotary press, or the like.
[0028] A medicinal ingredient that can used in the present invention may be in any form, such as solid form, crystalline form, oil form, or solution form, and one or two or more medicinal ingredients selected from, for example, antipyretic antiinflammatory analgesics, analeptic and health-care drugs, psychotropic drugs, antidepressants, antianxiety drugs, sedative-hypnotics, antispasmodics, central nervous system agents, cerebral metabolism improving agents, cerebral blood flow improving agents, antiepileptic drugs, sympathomimetic agents, gastrointestinal drugs, antacids, antiulcer agents, antitussives/expectorants, antiemetics, respiratory stimulants, bronchodilators, antiallergic drugs, antihistamines, agents for dental and oral use, cardiotonics, antiarrhythmic agents, diuretics, hypotensive agents, vasoconstrictors, coronary vasodilators, peripheral vasodilators, anticoagulants, agents for hyperlipidemia, cholagogues, antibiotics, chemotherapeutic agents, agents for diabetes, agents for osteoporosis, antirheumatic drugs, skeletal muscle relaxants, spasmolytics, hormone preparations, alkaloid narcotics, sulfa drugs, drugs for treatment of gout, and antineoplastic drugs can be used.
[0029] Examples of the antipyretic antiinflammatory analgesics include acetaminophen, aspirin, ibuprofen, ethenzamide, diphenhydramine hydrochloride, dl-chlorpheniramine maleate, diclofenac sodium, dihydrocodeine phosphate, salicylamide, aminopyrine, noscapine, methylephedrine hydrochloride, phenylpropanolamine hydrochloride, serrapeptase, lysozyme hydrochloride, tolfenamic acid, mefenamic acid, flufenamic acid, ketoprofen, indomethacin, bucolome, pentazocine, caffeine, and anhydrous caffeine. Examples of the analeptic and health-care drugs include vitamins such as vitamin A, vitamin B1 (dibenzoyl thiamine, fursultiamine hydrochloride, and the like), vitamin B2 (riboflavin butyrate and the like), vitamin B6 (pyridoxine hydrochloride and the like), vitamin B12 (hydroxocobalamin acetate, cyanocobalamin, and the like), vitamin C (ascorbic acid, sodium L-ascorbate, and the like), vitamin D, and vitamin E (d-α-tocopherol acetate and the like); minerals such as calcium, magnesium, and iron; proteins; amino acids; oligosaccharides; and herbal medicines. Examples of the psychotropic drugs include chlorpromazine and reserpine. Examples of the antidepressants include amphetamine, imipramine, and maprotiline hydrochloride. Examples of the antianxiety drugs include diazepam, alprazolam, and chlordiazepoxide. Examples of the sedative-hypnotics include estazolam, diazepam, nitrazepam, perlapine, and phenobarbital sodium. Examples of the antispasmodics include scopolamine hydrobromide, diphenhydramine hydrochloride, and papaverine hydrochloride. Examples of the central nervous system agents include citicoline. Examples of the cerebral metabolism improving agents include meclofenoxate hydrochloride. Examples of the cerebral blood flow improving agents include vinpocetine. Examples of the antiepileptic drugs include phenytoin and carbamazepine. Examplse of the sympathomimetic agents include isoproterenol hydrochloride. Examples of the gastrointestinal drugs include stomachics and digestants such as diastase, saccharated pepsin, Scopolia extract, cellulase AP3, lipase AP, and cinnamon oil; and intestinal drugs such as berberine chloride, antibiotics-resistant lactic acid bacteria, and bifidobacteria. Examples of the antacids include magnesium carbonate, sodium bicarbonate, magnesium aluminometasilicate, synthetic hydrotalcite, precipitated calcium carbonate, and magnesium oxide. Examples of the antiulcer agents include lansoprazole, omeprazole, rabeprazole, cimetidine, famotidine, and ranitidine hydrochloride. Examples of the antitussives/expectorants include cloperastine hydrochloride, dextromethorphan hydrobromide, theophylline, potassium guaiacolsulfonate, guaifenesin, and codeine phosphate. Examples of the antiemetics include difenidol hydrochloride and metoclopramide. Examples of the respiratory stimulants include levallorphan tartrate. Examples of the bronchodilators include theophylline and salbutamol sulfate. Examples of the antiallergic drugs include amlexanox and seratrodast. Examples of the antihistamines include diphenhydramine hydrochloride, promethazine, isothipendyl hydrochloride, and dl-chlorpheniramine maleate. Examples of the agents for dental and oral use include oxytetracycline, triamcinolone acetonide, chlorhexidine hydrochloride, and lidocaine. Examples of the cardiotonics include digoxin and caffeine. Examples of the antiarrhythmic agents include procainamide hydrochloride, propranolol hydrochloride, and pindolol. Examples of the diuretics include furosemide, isosorbide, and hydrochlorothiazide. Examples of the hypotensive agents include captopril, delapril hydrochloride, hydralazine hydrochloride, labetalol hydrochloride, manidipine hydrochloride, candesartan cilexetil, methyldopa, and perindopril erbumine. Examples of the vasoconstrictors include phenylephrine hydrochloride. Examples of the coronary vasodilators include carbocromen hydrochloride, molsidomine, and verapamil hydrochloride. Examples of the peripheral vasodilators include cinnarizine. Examples of the anticoagulants include dicumarol. Examples of the agents for hyperlipidemia include cerivastatin sodium, simvastatin, pravastatin sodium, and atorvastatin calcium hydrate. Examples of the cholagogues include dehydrocholic acid and trepibutone. Examples of the antibiotics include cephem antibiotics such as cephalexin, amoxicillin, cefaclor, pivmecillinam hydrochloride, cefotiam hexetil hydrochloride, cefadroxil, cefixime, cefditoren pivoxil, cefteram pivoxil, and cefpodoxime proxetil; synthetic antimicrobials such as ampicillin, cyclacillin, nalidixic acid, and enoxacin; monobactam antibiotics such as carumonam sodium; penem antibiotics; and carbapenem antibiotics. Examples of the chemotherapeutic agents include sulfamethizole. Examples of the agents for diabetes include tolbutamide, voglibose, pioglitazone hydrochloride, glibenclamide, and troglitazone. Examples of the agents for osteoporosis include ipriflavone. Examples of the skeletal muscle relaxants include methocarbamol. Examples of the spasmolytics include meclizine hydrochloride and dimenhydrinate. Examples of the antirheumatic drugs include methotrexate and bucillamine. Examples of the hormone preparations include liothyronine sodium, dexamethasone sodium phosphate, prednisolone, oxendolone, and leuprorelin acetate. Examples of the alkaloid narcotics include opium, morphine hydrochloride, ipecac, oxycodone hydrochloride, opium alkaloid hydrochloride and cocaine hydrochloride. Examples of the sulfa drugs include sulfisomidine and sulfamethizole. Examples of the drugs for treatment of gout include allopurinol and colchicine. Examples of the antineoplastic drugs include 5-fluorouracil, uracil, and mitomycin. The active ingredient may be diluted with a diluent or the like commonly used in the field of medicine, food, etc., and may be treated to mask the bitter taste of its own.
[0030] Examples of medicinal ingredients that can be preferably used in the present invention are water-labile substances.
[0031] Specific examples of such medicinal ingredients include methylmethioninesulfonium chloride; amino acids (aspartic acid, cysteine, and the like); various vitamins (vitamin B1, vitamin B2, vitamin B6, vitamin B12, vitamin C, nicotinamide, vitamine P, derivatives of these vitamins, and the like) and enzymes (starch digesting enzymes, protein digesting enzymes, fat digesting enzymes, cellulolytic enzymes, and the like); and herbal medicines (garlic, oxoamidine, and powdered or dried extracts of Astragalus root, Eleutherococcus senticosus , hop ( Humulus lupulus ), Coix seed, Swertia herb, pilose antler (Cervi Parvum Cornu), Glycyrrhiza, Platycodon root, cinnamon bark, Asiasarum root, peony root, Atractylodes lancea rhizome, ginger, ginseng root, and the like).
[0032] Examples of the sugar alcohol that can be used in the present invention include mannitol, erythritol, xylitol, maltitol, and sorbitol.
[0033] Examples of the sugar that can be used in the present invention include lactose, sucrose, glucose, and trehalose.
[0034] Additives disclosed below can be further added to an orally disintegrating tablet provided according to the present invention, as long as the tablet exerts the effects of the invention.
[0035] Examples of the additives that can be used in the present invention include binders, lubricants, disintegrants, pH adjusting agents, fluidizers, surfactants, coloring agents, sweeteners, and coating agents.
[0036] Examples of the binders that can be used in the present invention includes ethyl acrylate-methyl methacrylate copolymer, aminoalkyl methacrylate copolymer RS, aminoalkyl methacrylate copolymer E, sodium alginate, ethyl cellulose, carrageenan, carboxyvinyl polymer, carboxy methyl ethyl cellulose, agar, copolyvidone, purified shellac, dextrin, hydroxyethyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl starch, hydroxypropyl cellulose, vinylpyrrolidone-vinyl acetate copolymer, hypromellose, partially pregelatinized starch, pullulan, pectin, polyvinyl alcohol-polyethylene glycol graft copolymer, povidone, polyvinyl alcohol, methacrylic acid copolymer L, methacrylic acid copolymer LD, methacrylic acid copolymer S, and methylcellulose.
[0037] Examples of the lubricants that can be used in the present invention include carmellose calcium, carmellose sodium, glycerin, glycerin fatty acid ester, wheat starch, sucrose fatty acid ester, stearyl alcohol, stearic acid, cetanol, gelatin, corn starch, potato starch, polyoxyethylene-polyoxypropylene glycol, polysorbate, macrogol, glyceryl monostearate, and sodium lauryl sulfate.
[0038] Examples of the disintegrants that can be used in the present invention include carmellose calcium, carboxymethyl starch sodium, croscarmellose sodium, crospovidone, cellulose or derivatives thereof, and starch or derivatives thereof.
[0039] Examples of the pH adjusting agents that can be used in the present invention include citric acid and its salts, phosphoric acid and its salts, carbonic acid and its salts, tartaric acid and its salts, fumaric acid and its salts, acetic acid and its salts, amino acids and its salts, succinic acid and its salts, and lactic acid and its salts.
[0040] Examples of the fluidizers that can be used in the present invention include light anhydrous silicic acid, hydrous silicon dioxide, titanium oxide, stearic acid, corn gel, and heavy anhydrous silicic acid.
[0041] Examples of the surfactants that can be used in the present invention include phospholipid, glycerin fatty acid ester, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyethylene glycol fatty acid ester, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, sucrose fatty acid ester, sodium lauryl sulfate, polysorbates, sodium hydrogen phosphates, and potassium hydrogen phosphates.
[0042] Examples of the coloring agents that can be used in the present invention include iron sesquioxide, yellow iron sesquioxide, Food Yellow No. 5, Food Yellow No. 4, aluminum chelate, titanium oxide, and talc.
[0043] Examples of the sweeteners that can be used in the present invention include saccharin, aspartame, acesulfame potassium, thaumatin, and sucralose.
[0044] Examples of the coating agents that can be used in the present invention include hydroxypropyl cellulose, hydroxypropylmethylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone-ethyl acrylate, methyl methacrylate copolymer dispersions, hydroxypropylmethylcellulose acetate succinate, and methacrylic acid copolymers.
[0045] According to the present invention, it is preferable that the content of the sugar alcohol or/and the sugar accounts for 50 to 90% of the content of the sugar alcohol or/and the sugar and the various additives excluding the medicinal ingredient. According to the present invention, it is also preferable that the silica and the sugar alcohol or/and the sugar form a composite particle.
[0046] There is no particular limitation to the tableting method for an orally disintegrating tablet provided according to the present invention, as long as the tablet exerts the effects of the invention. Examples of the tableting method that can be used in the present invention include a direct compression method, a dry indirect compression method, and a wet indirect compression method.
[0047] An orally disintegrating tablet provided by the present invention is shaped using, for example, a single-punch tableting machine, a rotary tableting press, or the like. Although there is no particular limitation to the shape of solid formulations according to the present invention, the tablet may be round, caplet, doughnut, oblong, and the like, may be multilayered, cored, and the like, and can be further coated with a coating agent. Optionally, the tablet may be provided with distinguishing characters, symbols, or marks, and may be provided with a dividing line so that the tablet can be divided.
Effects of Invention
[0048] According to the present invention, it has became possible to provide an orally disintegrating tablet that is capable of disintegrating with a small amount of water, having a rapid disintegration time, and being maintained stably in a tablet form, which could not be achieved by conventional procedures.
BEST MODE FOR CARRYING OUT THE INVENTION
[0049] Hereinafter, the best mode for carrying out the invention will be disclosed.
EXAMPLES
Example 1
[0050] Mannitol-silica composite particles were prepared by dissolving and dispersing 9 kg of mannitol and 6 kg of silica (Sylysia 350: Fuji Silysia Chemical Ltd.) in 85 kg of water and performing spray drying using a spray dryer (NB-12: Ohkawara Kakohki Co., Ltd.).
[0051] Next, 1 part by weight of the mannitol-silica composite particles and 1 part by weight of crospovidone were added to and mixed with 8 parts by weight of mannitol. The mixture was dry granulated using a roller compactor (a model of TF-MINI: Freund Corporation), and then subjected to particle size regulation using a COMIL (a model of QC-1975: Powrex Corporation), and then subjected to a 75 μm sieve to eliminate fine powders, and the remaining was obtained as granules for tableting. Then, 1 part by weight of magnesium stearate was mixed with 99 parts by weight of the granules for tableting, and flat-faced bevel-edged tablets having a tablet diameter of 7.5 mm and a tablet weight of 150 mg were produced at a compression pressure of 9 kN.
Example 2
[0052] Erythritol-silica composite particles were prepared by dissolving and dispersing 10 kg of erythritol and 5 kg of silica (Sylysia 350: Fuji Silysia Chemical Ltd.) in 50 kg of water and performing spray drying using a spray dryer (NB-12: Ohkawara Kakohki Co., Ltd.).
[0053] Next, 1 part by weight of the erythritol-silica composite particles and 1 part by weight of crospovidone were added to and mixed with 8 parts by weight of erythritol. The mixture was dry granulated using a roller compactor (a model of TF-MINI: Freund Corporation), and then subjected to particle size regulation using a COMIL (a model of QC-1975: Powrex Corporation), and then subjected to a 75 μm sieve to eliminate fine powders, and the remaining was obtained as granules for tableting. Then, 1 part by weight of magnesium stearate was mixed with 99 parts by weight of the granules for tableting, and flat-faced bevel-edged tablets having a tablet diameter of 7.5 mm and a tablet weight of 150 mg were produced at a compression pressure of 9 kN.
Example 3
[0054] First, 0.8 kg of mannitol-silica composite particles and 0.8 kg of crospovidone were added to and mixed with 6.4 kg of mannitol. The mixture was dry granulated using a roller compactor (a model of WP160×60N: Turbo Kogyo Co., Ltd.), and then particle size regulation was performed using a roll granulator (GRN-T-54S: Nippon Granulator Co., Ltd.) to obtain granules for tableting. Then, 1 part by weight of magnesium stearate was mixed with 99 parts by weight of the granules after the particle size regulation, and flat-faced bevel-edged tablets having a tablet diameter of 8.0 mm and a tablet weight of 200 mg were produced at a compression pressure of 9 kN.
Comparative Example 1
[0055] With 79 parts by weight of mannitol, 10 parts by weight of mannitol-silica composite particles, 10 parts by weight of crospovidone, and 1 part by weight of magnesium stearate were mixed, and flat-faced bevel-edged tablets having a tablet diameter of 8.0 mm and a tablet weight of 200 mg were produced at a compression pressure of 9 kN.
Comparative Example 2
[0056] With 89 parts by weight of crystalline cellulose, 10 parts by weight of crospovidone and 1 part by weight of magnesium stearate were mixed, and flat-faced bevel-edged tablets having a tablet diameter of 8.0 mm and a tablet weight of 200 mg were produced at a compression pressure of 9 kN.
Examination Example 1
[0057] The respective orally disintegrating tablets produced by the production methods described in Examples 1 to 3 and Comparative Example 1 were examined with regard to tablet hardness, disintegration time, and friability. The tablet hardness was determined using a tablet hardness tester (a model of 6D: Schleuniger). The tablet disintegration time was determined as follows: a tablet was introduced in the oral cavity of each of four subjects (healthy adult men and women), the time from the introduction until complete disintegration in the oral cavity of the tablet was measured, and an average was obtained from the measured times. The tablet friability was tested and determined in compliance with the friability testing method prescribed in the Japanese Pharmacopoeia 15th edition.
[0058] The results of determination were as shown in Table 1.
[0000]
TABLE 1
Comparative
Example 1
Example 2
Example 3
Example 1
Hardness
45N
60N
56N
58N
Friability
0.083%
0.016%
0.043%
0.162%
Disintegration time
8 seconds
10 seconds
10 seconds
10 seconds
[0059] As shown in Table 1, it became clear that the orally disintegrating tablets produced in the examples, which are embodiments of the present invention, have a friability decreased to ½ to 1/10 as compared with the orally disintegrating tablets of Comparative Example 1 produced without using dry granulation as in conventional procedures, while the orally disintegrating tablets produced in the examples are excellent in terms of having adequate mechanical strength and disintegration time as compared with those produced by conventional procedures.
[0060] Thus, it became clear that an orally disintegrating tablet according to the present invention is the orally disintegrating tablet that hardly cracks or chips during production, packaging, transport, and the like, as compared with those produced by conventional procedures.
Examination Example 2
[0061] Next, the orally disintegrating tablets produced in Example 3 and the orally disintegrating tablets, produced in Comparative Example 2 were allowed to stand for 12 hours under the conditions of a temperature of 60° C. and a humidity of 75%, and the amount of water absorption per tablet was determined from the amount of increase in tablet weight.
[0000]
TABLE 2
Comparative
Example 3
Example 2
Amount of water
0.87 mg
2.63 mg
absorption per tablet
[0062] As shown in Table 2, it became clear that the orally disintegrating tablets produced in Example 3, which is an embodiment of the present invention, has a lower amount of water absorption than the orally disintegrating tablets of Comparative Example 2 produced by dry granulation with crystalline cellulose. That is to say, it became clear that an orally disintegrating tablet obtained according to the present invention has a reduced amount of water absorption in the oral cavity and has superior storage stability, as compared with those of conventional procedures. It is predicted that disintegration of the tablet with such a small amount allows for reduction in discomfort upon ingestion.
[0063] Accordingly, it became clear that the present invention can provide an orally disintegrating tablet that disintegrates with a small amount of water, has a rapid disintegration time, and is maintained in a tablet form stably, as compared with those provided by conventional procedures.
[0064] According to the present invention, it has became possible to provide an orally disintegrating tablet that is capable of disintegrating with a small amount of water, having a rapid disintegration time, and being maintained stably in a tablet form.
[0065] Thus, it has became possible to provide an orally disintegrating tablet that, in particular, hardly cracks or chips during production, packaging, transport, and the like. Moreover, the orally disintegrating tablet allows for people who have low swallowing ability, such as children and elderly people to be easily and conveniently taken. | It is an object to provide an orally disintegrating tablet produced by dry granulation and compression, having a hardness of 40 N or more, a disintegration time of 30 seconds or shorter, a friability of 0.1% or less, and an excellent feeling upon ingestion, that is capable of disintegrating with a small amount of water, having a rapid disintegration time, and being maintained stably in a tablet form, which could not been achieved by conventional procedures. Disclosed is an orally disintegrating tablet produced by dry granulation which contains a medicinal ingredient with silica, and sugar alcohol or/and sugar. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Korean Application No. 2005-8603, filed Jan. 31, 2005, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] An aspect of the present invention relates to an image reading and/or reproducing apparatus. More particularly, the present invention relates to an image reading and/or reproducing apparatus that provides enhanced image reading speed by improving a document feeding structure of the image reading and/or reproducing apparatus.
[0004] 2. Description of the Related Art
[0005] FIG. 1 is a view of a schematic operation of a conventional image reading apparatus 1 . According to the conventional image reading apparatus, when reading a single-sided image, a document 3 supplied from a document feeding tray 2 is picked up by a pick-up roller 5 to be fed to a document convey path 7 . The document 3 , fed by the pick-up roller 5 , passes an Automatic Document Feeder (ADF) roller 9 to be separated into a single sheet. A friction pad 11 is formed adjacently to an opposed surface of the ADF roller 9 to provide a frictional force when the document 3 is separated. The document 3 , separated into a single sheet by the ADF roller 9 , is then transmitted via convey rollers 13 , 15 to an image scan unit 17 .
[0006] A single side of the document 3 transmitted to the image scan unit 17 is read, then the document is conveyed to a discharge roller 21 , where the document is loaded in order on a document discharge tray 23 by the discharge roller 21 .
[0007] When reading a double-sided image, one side of the document 3 is scanned according to the same operational principles as are described above. The trailing end of the document 3 is positioned upstream of the image scan unit as the conveying direction of the document is reversed along a document reverse path 25 prior to the document being scanned again and then discharged to the document discharge tray 23 via the discharge roller 21 . A path conversion device 26 is formed around the document reverse path 25 to selectively open the document reverse path 25 and the document convey path 7 . The document 3 , moved to the document reverse path 25 , passes a reverse roller 27 and then U-turns at a position of the convey roller 15 such that the surfaces of the document 3 are reversed with respect to the image scan unit. The image scan unit 17 then reads an image on the document 3 to complete the double-sided image reading process.
[0008] A problem exists, however, in that, when reading the double-sided image, the order of the documents 3 that are discharged onto the document discharge tray 23 is necessarily different from the order of the documents 3 as they were loaded on the document feeding tray 2 . The cause of the difference will be described in detail as follows.
[0009] FIG. 2A is a view of a status of double-sided documents loaded on the document feeding tray 2 of a conventional image reading apparatus 1 , and FIG. 2B is a view of an example of the double-sided documents discharged from the apparatus once the conventional image reading apparatus performs a reading of both sides of the double-sided image.
[0010] Referring to FIG. 2A , when, for example, double-sided documents with 6 pages, 3 sheets are loaded, the double-sided documents are loaded on the document discharge tray 23 in order of pages 1 , 2 , 3 , 4 , 5 , 6 (hereinafter, when the first image forming page is positioned at the uppermost side, this arrangement will be referred to as “face up”, whereas when the first image forming page is positioned at the lowermost side, this arrangement will be referred to as “face down”), a plurality of the loaded documents are sequentially separated from the uppermost surface of the stack to perform a reading of both sides of the double-sided image as described above.
[0011] As illustrated in FIG. 2B , the documents are output in order of pages 2 , 1 , 4 , 3 , 6 , 5 from the lowermost side on the document discharge tray 23 such that the pages are not arranged in a correct order.
[0012] In order to solve the above problem, as the reading of the double-sided images of the document 3 is completed, the document 3 is reversely conveyed via the document reverse path 25 and U-turned via the convey roller 15 to be discharged. In other words, the document 3 travels through a portion 7 a of the document convey path 7 that corresponds to a section B between a starting point S 1 and an ending point E 1 of the document reverse path 25 three times.
[0013] When reading the double-sided images according to a conventional art as described above, additional reverse operations are performed to arrange the order of the discharged document pages. Therefore, a long time is required to read images.
SUMMARY OF THE INVENTION
[0014] An aspect of the present invention solves the above-mentioned and/or other problems and provides an image reading apparatus which reduces a time required to read double-sided images by improving a feeding structure of a document.
[0015] In order to achieve the above and/or other aspects, according to a first embodiment of the present invention, there is provided an image reading apparatus comprising a plurality of document feeding trays, an image scan unit to scan an image of the document fed from the document feeding trays, and a document feeding unit to selectively feed the document of a document stack on one of the plurality of document feeding trays from the uppermost surface of the stack of documents, and feeding the document of a document stack on the other document feeding tray from the lowermost surface of the stack of documents.
[0016] The image reading apparatus further comprises a reverse unit to reverse the document to a position that is upstream of the image scan unit as the image scan unit completes a scanning of the image of the document.
[0017] At least one of the document feeding trays, which feeds the document from the uppermost surface of the stack of documents and the document feeding tray which feeds the document from the lowermost surface of the stack of documents, is a single-sided document tray.
[0018] A single-sided document may be loaded face up on the single-sided document feeding tray.
[0019] The document feeding tray to feed the document from the lowermost surface of the stack of documents may be a double-sided document feeding tray. A double-sided document may be loaded face up or down on the double-sided document feeding tray.
[0020] The document feeding unit which feeds the document from the uppermost surface of the stack of documents may comprise a pick-up roller to pick up the document from the uppermost side of the document stack on the document feeding tray; a first separation roller to separate the picked-up document into a single sheet; and a first friction pad opposed to the first separation roller and to provide a frictional force in the separating of the document from the other documents into a single sheet.
[0021] The document feeding unit which feeds the document from the lowermost surface of the stack of documents may comprise a second separation roller to pick up the document from the lowermost surface of the stack of documents on the document feeding tray to separate into a single sheet, and a second friction pad opposed to the second separation roller to provide a frictional force in the separating of the double-sided document from the other documents into a single sheet.
[0022] A single-sided document sensor and a double-sided document sensor may be provided in each of the single-sided document feeding tray and the double-sided document feeding tray.
[0023] The image reading apparatus further comprises a plurality of document convey paths to guide the document fed from the plurality of document feeding trays to the image scan unit, an image scan path to discharge the document fed from the document convey path onto the document discharge tray via the image scan unit, and a document reverse path to feed the document, reversed from the document reverse unit, to a position that is upstream of the image scan unit.
[0024] The first document convey path and the second document convey path may be formed in substantially flattened U shapes and joined with each other at a position that is upstream of the image scan unit, a starting point of the document reverse path is formed at a position that is downstream of the image scan unit, and a finishing point of the document reverse path is connected with a joint point of the first and the second document convey paths.
[0025] Additional and/or other aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
[0027] FIG. 1 is a schematic view of an operation status of a conventional image reading apparatus;
[0028] FIG. 2A is a view of a status of double-sided documents loaded on a document feeding tray of the conventional image reading apparatus shown in FIG. 1 ;
[0029] FIG. 2B is a view of an example of double-sided documents not arranged in a correct order of pages on the document discharge tray when the conventional image reading apparatus performs reading double-sided images;
[0030] FIG. 3 is a view of an example of an image reading apparatus according to an embodiment of the present invention;
[0031] FIG. 4A is a view of a status of single-sided documents loaded face up on a single-sided document feeding tray according to an embodiment of the present invention;
[0032] FIG. 4B is a view of a status of double-sided documents loaded face down on a double-sided document feeding tray according to an embodiment of the present invention;
[0033] FIG. 4C is a view of an example of single-sided documents loaded face down on a single document feeding tray according to an embodiment of the present invention;
[0034] FIG. 4D is a view of an example of double-sided documents loaded face up on a double-sided document feeding tray according to an embodiment of the present invention;
[0035] FIG. 5A is a view of a status of single-sided documents discharged on the document discharge tray when the single-sided documents are loaded as shown in FIG. 4A and fed from the uppermost surface of the stack of documents;
[0036] FIG. 5B is a view of a status of double-sided documents discharged on the document discharge tray when the double-sided documents are loaded face down as shown in FIG. 4B and fed from the lowermost surface of the stack of documents;
[0037] FIG. 5C is a view of a status of single-sided documents discharged on the document discharge tray when the single-sided documents are loaded face up as shown in FIG. 4A and fed from the lowermost surface of the stack of documents;
[0038] FIG. 5D is a view of a status of double-sided documents discharged on the document discharge tray when the double-sided documents are loaded face up as shown in FIG. 4D and fed from the lowermost surface of the stack of documents;
[0039] FIG. 5E is a view of a status of double-sided documents discharged on the document discharge tray when the double-sided documents are loaded face down as shown in FIG. 4B and fed from the uppermost surface of the stack of documents; and
[0040] FIG. 5F is a view of a status of double-sided documents discharged on the document discharge tray when the double-sided documents are loaded face up as shown in FIG. 4D and fed from the lowermost surface of the stack of documents.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0041] Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.
[0042] FIG. 3 is a view of an example of an image reading apparatus according to an embodiment of the present invention. Referring to FIG. 3 , a double-sided image reading and/or reproducing apparatus 100 comprises an image scan part S and an automatic document feeding part A. The image scan part S comprises an image scan body 101 , a document holder glass 103 , and an image scan unit 105 .
[0043] A document to be scanned is set on the document holder glass 103 , which comprises a platen glass 103 a and an automatic document feeder (ADF) glass 103 b, as illustrated in FIG. 3 . The platen glass 103 a sets documents to a fixed position thereon, and the ADF glass 103 b allows the documents D 1 , D 2 that are sequentially fed by an automatic document feeding unit 120 to come into contact with the ADF glass 103 b.
[0044] The image scan unit 105 is provided in the image scan body 101 and is provided in a lower portion of the body 101 below the ADF glass 103 b so as to be positioned to read images of the documents D 1 , D 2 that are continuously fed via the automatic document feeding unit 130 . The image scan unit 105 reciprocates in linear directions as illustrated by the horizontal arrow of FIG. 3 to read an image of a document fixed on the platen glass 103 a.
[0045] The automatic document feeding unit A comprises a feeding body 107 , a document feeding tray 110 , a document feeding unit 130 , a document convey path 150 , a document reverse unit 160 , a document discharge tray 170 , and a document sensor 190 .
[0046] The document feeding tray 110 comprises a single-sided document feeding tray 111 to load single-sided documents D 1 therein and a double-sided document feeding tray 113 to load double-sided documents D 2 therein.
[0047] FIG. 4A shows the documents D 1 loaded face-up on the single-sided document feeding tray 111 . Similarly, FIG. 4B shows the documents D 2 loaded face-down on the double-sided document feeding tray 113 .
[0048] The document feeding unit 130 comprises a single-sided document feeding unit 131 to feed the loaded document D 1 from the single-sided document tray 111 and a double-sided document feeding unit 133 to feed the loaded document D 2 from the double-sided document feeding tray 113 .
[0049] The single-sided document feeding unit 131 feeds the uppermost document loaded on the single-sided document feeding tray 111 from the uppermost surface of the stack of documents D 1 loaded thereon. The single-sided document feeding unit 131 comprises a pick-up roller 131 a to pick up the uppermost document, a first separation roller 131 b to insure that the document is separated from other documents into a single sheet, and a first friction pad 131 c opposed to the first separation roller 131 b to provide a frictional force in the separation operation.
[0050] The double-sided document feeding unit 133 comprises a second separation roller 133 a to slide the lowermost double-sided document D 2 out from under the stack of documents D 2 loaded on the double-sided document feeding tray 113 , and a second friction pad 133 b opposed to the second separation roller 133 a to provide a frictional force in the separation operation. The double-sided document feeding tray 113 may be inclined to a certain angle to smoothly feed the double-sided document D 2 between the second separation roller 133 a and the second friction pad 133 b. A pick-up roller may be additionally provided as the aforementioned single-sided document feeding unit 133 .
[0051] The document convey path 150 comprises a first convey path 151 to feed single-sided documents D 1 from the single-sided feeding unit 131 to the image scan unit 105 , a second convey path 153 to feed double-sided documents D 2 from the double-sided document feeding unit 133 to the image scan unit 105 , and an image scan path 155 to discharge the single sided document D 1 or the double sided document D 2 from either the first or second convey path 151 or 153 , respectively, from the image scan unit 105 to the document discharge tray 170 .
[0052] A document reverse path 157 is provided to convey double-sided documents D 2 back to the image scan path 155 upstream of the image scan unit 105 . Here, the conveying direction of the double-sided documents D 2 is reversed while the documents travel along the image scan path 155 downstream from the image scan unit 105 . The first and second convey paths 151 , 153 intersect at the image scan path 155 upstream of the image scan unit 105 . A starting point S 2 of the document reverse path 157 is connected with the image scan path 155 downstream from the image scan unit 105 , and a finishing point E 2 of the document reverse path 157 is connected with the image scan path 155 upstream of the image reading unit 105 . The finishing point E 2 is connected with the point of intersection of the first and second paths 151 , 153 .
[0053] The document reverse unit 160 positions a trailing end of the document D 2 upstream of the image scan unit 105 and reverses the conveying direction of document as the scanning of a first side of the document D 2 is completed by the image scan unit 105 . The document reverse unit 160 comprises a motor (not shown) to drive forward and backward, and a discharge roller 161 to rotate via a power of the motor. The discharge roller 161 discharges the documents D 1 or D 2 onto the document discharge tray 170 when rotating forward (clockwise), and reverses the document D 2 when rotating backward (counterclockwise). A reverse sensor 163 may be added at a front side of the turning point S 2 of the image scan path 155 to sense that a document D 2 is located upstream of the reverse sensor 163 and to aid in a determination of an operation of the document reverse unit 160 .
[0054] The document sensor 190 comprises a single-sided document sensor 191 to sense whether at least one single-sided document D 1 is loaded on the single-sided document feeding tray 111 and a double-sided document sensor 193 to sense whether at least one double-sided document D 2 is loaded on the double-sided document feeding tray 113 . Here, a double-sided image scan mode or a single-sided image scan mode may be designated as an operational mode of the apparatus depending on the sensing condition of the single-sided document sensor 191 and the double-sided document sensor 193 .
[0055] A scan roller 201 is provided at a front side of the image scan unit 105 to cause the single-sided document D 1 to make a U-turn towards the image scan path 155 and to feed the double-sided document D 2 onto the image scan path 155 . A scan sensor 203 is provided to sense a position of the conveyed document D 1 or D 2 and to provide data to aid in the decision as to an operational timing point of the image scan unit 105 . A path conversion device 205 is provided around the turning point S 2 to traverse the document convey path. As shown in FIG. 3 , the path conversion device 205 may comprise a gate bar 205 a. If the path conversion device 205 is used, one end of the path conversion device 205 should be hinged such that the path conversion device 205 is biased to pivot downward so as to maintain an opened state of the document reverse path 157 . However, the path conversion device 205 may be pivoted upward by a conveying force of the document D 1 or D 2 so as to open the image scan path 155 as the document D 1 or D 2 is conveyed via the image scan path 155 .
[0056] With references to FIGS. 3, 4A , and 5 A, the single-sided image scan operation will now be described. Referring to FIGS. 3 and 4 A, when the single-sided documents D 1 are loaded face-up on the single-sided document feeding tray 113 , the pick-up roller 131 a is driven depending on the sensing condition of the single-sided document sensor 191 .
[0057] The pick-up roller 131 a picks up an uppermost loaded single-sided document from the uppermost surface of the stack of documents in the single-sided document feeding tray 113 , and the picked-up single-sided document D 1 passes between the first separation roller 131 b and the first friction pad 131 c to insure that the document is separated from other documents into a single sheet.
[0058] The single-sided document D 1 then passes the first convey path 151 and is made to make a curving U-turn by an operation of the scan roller 201 such that the single-sided document D 1 is conveyed via the image scan path 155 to the image scan unit 105 . After the image side of the document is read, the single-sided document D 1 is discharged via the discharge roller 161 onto the document discharge tray 170 so as to complete the single-sided image reading process. The gate bar 205 a, which acts as the path conversion device 205 , according to this embodiment of the invention, rotates upward by the force of the document D 1 hitting a face of the gate bar 205 a as the document D 1 is conveyed.
[0059] Once all of the single-sided documents D 1 are discharged, as illustrated in FIG. 5A , the single-sided documents D 1 are loaded on the document discharge tray 170 with the first image forming page, which is page 1 , acting as the lowermost facing page. In other words, the single-sided document D 1 is loaded from the lowermost surface of the stack of discharged documents D 1 in order of pages 1 , 2 , 3 , 4 , 5 , 6 .
[0060] With references to FIGS. 3, 4B , 5 B, the double-sided image scan operation will now be explained. Referring to FIGS. 3 and 4 B, when the double-sided document D 2 is loaded face-down on the double-sided document feeding tray 113 , the second separation roller 133 a rotates depending on the sensing condition of the double-sided document sensor 193 to sequentially slide the lowermost double-sided document D 2 out from under the stack of documents D 2 loaded on the double-sided document feeding tray 113 . The slid-out double-sided document D 2 is separated from the other documents into a single sheet by a frictional force of the friction pad 133 b. The separated double-sided document D 2 passes along the second convey path 153 and is made to make a U-turn by an operation of the scan roller 201 so as to be conveyed via the image scan path 155 to the image scan unit 105 . After a first side (front page of the document on the double-sided document feeding tray 113 ) is read, the double-sided document D 2 is conveyed through the image scan path 155 , and the reverse sensor 203 senses that the double-sided document D 2 is upstream of the reverse sensor 203 . The discharge roller 161 then begins to rotate backward relative to the discharge direction a certain time after the reverse sensor 203 senses the position of the double-sided document D 2 . Accordingly, the double-sided document D 2 is conveyed backward along the document reverse path 157 and is made to make a U-turn by the scan roller 201 such that the second side (a rear page of the document on the double-sided document feeding tray 113 ) faces toward the image scan unit 105 , i.e., the double-sided document D 2 is reversed. The double-sided document D 2 is then conveyed along the image scan path 155 and passes the image scan unit 105 so that the second side of the document D 2 is read. The double-sided document D 2 is then discharged onto the document discharge tray 170 .
[0061] When all of the double-sided documents D 2 are discharged, the first image forming page, i.e., page 1 , of the double-sided documents D 2 , is positioned face down at the lowermost surface of the stack of documents D 2 on the document discharge tray 170 as shown in FIG. 5B with the other documents D 2 similarly aligned. In other words, the double-sided documents D 2 are loaded face down in order of pages 1 , 2 , 3 , 4 , 5 , 6 on the document discharge tray 170 in the same order as the order of the pages of the documents D 2 when the documents were loaded on the double-sided document feeding tray 113 .
[0062] The image reading apparatus 100 as described above may be coupled with a multi-operational peripheral device such as a copier with combination of an image forming device (not shown).
[0063] According to the above noted embodiments of the document feeding tray 110 , documents are fed from a lowermost surface of the stack of documents in the double-sided document feeding tray 113 , whereas documents are fed from an uppermost surface of the stack of documents in the single sided document feeding tray 111 . However, this arrangement should not be considered as limiting. The document feeding tray 110 may be differently applied. For example, both document feeding trays 111 , 113 may be used as a single-sided document feeding tray. Additionally, the double-sided document D 2 may be loaded with documents either face-up or face-down.
[0064] As another example in another embodiment, FIG. 5C is a view of the single-sided documents D 1 after they have been discharged on the discharge tray 170 —in the case where the documents D 1 would have been loaded face up on the single-sided document feeding tray 111 and fed from the lowermost surface of the stack of documents D 1 . As shown in FIG. 5C , the documents D 1 were discharged in a reverse order of the pages, as compared to the original order of the pages, with the image forming pages facing down. Thus, when the single-sided documents D 1 are fed from the lowermost surface of the stack of documents D 1 , no problem exists with respect to the discharge order.
[0065] However, the printing speed may be slowed if a multi-operational peripheral device is attached to the image reading apparatus 100 that adds an image forming part operating based on the information read by the image reading apparatus 100 . In other words, since the image-scanned pages are in order of 6 , 5 , 4 , 3 , 2 , 1 , a printing operation may have to be performed backward with respect to the order of the pages in order to arrange for a correct discharge order. In this case, a long time may be required for the printing operation. Moreover, while the embodiments discussed herein refer to documents with 6 pages, a scanning operation of 100 pages may require a much longer time for the printing operation.
[0066] The single-sided document D 1 may be loaded face-down on the document feeding tray 110 (in fact, either document feeding tray 113 or 111 ). FIG. 4C is a view of an example of the single-sided document D 1 loaded in the face-down form on the document feeding tray 111 . As a surface of the page without an image thereon faces up, the surface of the page having the image thereon cannot face toward the image scan unit 105 as the document passes along the image scan path whether the document is fed from the uppermost surface of the stack of documents or from the lowermost surface of the stack of documents. In this case, if the single-sided document D 1 is reversed, as in the scan process of the double-sided document D 2 , this embodiment may be useful in image scanning or reproducing operations. However, this embodiment may also slow the image scan speed. Therefore, when the single-sided document D 1 is to be scanned, the single-sided document D 1 should be loaded face-up and the documents should be fed from the uppermost surface of the stack of documents D 1 .
[0067] FIG. 4D is a view of an example of the double-sided documents D 2 loaded face-up form on the document feeding tray 113 , and FIG. 5D is a view of an example of the double-sided documents D 2 after they have been discharged on the discharge tray 170 and when the double-sided documents D 2 , loaded as shown in FIG. 4D , are fed from the lowermost surface of the stack of documents D 2 . As shown in FIGS. 4D and 5D , the double-sided documents D 2 on the document feeding tray 110 are loaded in the same order as the order of the double-sided documents D 2 when they are discharged onto the discharge tray 170 . However, since the document is scanned in order of pages 6 , 5 , 4 , 3 , 2 , 1 , the printing speed is slowed, as is described above. Accordingly, when the double-sided document D 2 is scanned, the double-sided document D 2 on the document feeding tray 110 should be fed from the lowermost surface of the stack of documents D 2 .
[0068] As a reference, when the double-sided documents D 2 , loaded on the document feeding tray 110 , are fed from the uppermost surface of the stack of documents D 2 , the following examples explain the problem solved by the invention.
[0069] FIG. 5E is a view of an example of the double-sided documents D 2 discharged on the discharge tray 170 when the double-sided documents D 2 are loaded face-down as shown in FIG. 4B and fed from the uppermost surface of the stack of documents D 2 . The double-sided documents D 2 are discharged on the discharge tray 170 in order of pages 5 , 6 , 3 , 4 , 1 , 2 from the lowermost surface of the discharged stack of documents D 2 .
[0070] Similarly, FIG. 5F is a view of an example of the double-sided documents D 2 discharged on the discharge tray 170 when the double-sided documents D 2 are loaded face-up as shown in FIG. 4D and fed from the uppermost surface of the stack of documents D 2 . The double-sided documents D 2 are discharged on the discharge tray 170 in order of pages 2 , 1 , 4 , 3 , 6 , 5 from the lowermost surface of the discharged stack of documents D 2 .
[0071] If the image reading apparatus according to embodiments of the present invention is applied, reducing a time to read images is possible since the conventional reverse operation is improved.
[0072] Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. | An image reading and/or reproducing apparatus, including a single sided document feeding tray and a double sided document feed tray to each supply a stack of documents to the apparatus; a document feeding unit to feed a document from a top of the stack of documents in the single sided document feeding tray, and to feed a document from a bottom of the stack of documents in the double sided document feeding tray; and an image scan unit to scan an image of the document fed from the document feeding unit. The apparatus further includes a reverse unit to position the double-sided document, fed by the document feeding unit, upstream of the image scan unit as the image scan unit completes a scanning of the image on a first side of the document such that the image scan unit may scan the image on a second side of the document. According to the above structure, reducing a time required to scan an image is possible. | 7 |
BACKGROUND OF THE INVENTION
This invention is directed to electrical circuit breakers and, more particularly, to electrical circuit breakers having a trip mechanism controlling the operation of the circuit breaker, wherein the trip mechanism includes a tip bar.
Circuit breakers are generally old and well known in the art. Examples of circuit breakers are disclosed in U.S. Pat. Nos. 5,705,968; 5,831,503; and 5,341,191. Such circuit breakers are used to protect electrical circuitry from damage due to an overcurrent condition, such as an overload condition or a relatively high-level short circuit condition.
Molded case circuit breakers include a pair of separable contacts per phase which may be operated either manually by way of a handle located on the outside of the case or automatically in response to an overcurrent condition. Circuit breakers include an operating mechanism that is designed to rapidly open and close the separable contacts, thereby preventing a moveable contact from stopping at any position which is intermediate to a fully open or a fully closed position. The circuit breaker also includes a trip mechanism having a means for sensing an overcurrent condition in the automatic mode of operation; a trip bar responsive to the sensing means; and a latch mechanism including a trigger mechanism. During an overcurrent condition, the trip bar responds to the sensing means and releases the trigger mechanism. The trigger mechanism releases a latching and releasing mechanism, which, in turn, opens the separable contacts.
The trip bar of the trip mechanism is rotatable by one or more trip sources to release the trigger mechanism. "Latch load" is conventionally defined as the force required by a test probe at a trip point on the trip bar, such as the actuation point for accessory attachments, to cause sufficient torque about the axial centerline of the trip bar necessary to release the trigger mechanism. At least two other torques are present on the trip bar during a tripping action.
First, there is a frictional torque resisting rotation of the trip bar due to friction between the trip bar and the operating mechanism side plates at the trip bar pivot points. The second torque is due to the load imposed by the trigger mechanism on the trip bar at a loading point. This torque tends to push the trip bar "off latch". The force associated with this torque is dependent upon many variables within the circuit breaker operating mechanism (e.g., biasing spring force, parts tolerance) which are normal manufacturing variables.
With suitable moments, a force (e.g., about 300 pounds) in the operating mechanism may be offset by a relatively small load (e.g., about 30 ounces) where a plunger engages the trip bar, thereby controlling a relatively large force with a relatively small force. As a result, even relatively small position variations in the latching and releasing mechanism may cause significant changes in the direction of the operating force. This, in turn, reflects directly in the corresponding latch load and "shock-out" sensitivity (i.e., the sensitivity of the operating mechanism to a premature release). The corresponding latch load may be subject to a relatively large amount of variation due to the various positions assumed by components of the operating mechanism and the latching and releasing mechanism resulting from: (1) normal manufacturing tolerances; (2) production heat-treating operations; and (3) normal operating variations between latching operations.
Sufficient latch load is required in order to maintain the circuit breaker operating mechanism in the latched position. Too little load may cause the operating mechanism to shock-out. For example, if the corresponding latch load is too small, the operating mechanism may shock-out to a trip position when the circuit breaker handle is moved to the ON position. Also, manual "push-to-trip" operation of the circuit breaker may be adversely affected in the OFF position of the operation mechanism. In such OFF position, the force of the operating mechanism is further reduced because a spring of the operating mechanism may be stretched less with respect to the ON position. In turn, the corresponding reduced latch load may be insufficient to overcome the normal frictional forces within the operating and trip mechanisms. Conversely, relatively large latch loads may inhibit the automatic mode of operation during an overcurrent condition. Too much load may prevent the operating mechanism from tripping after an overload or short circuit event is detected in the circuit breaker trip unit and a trip initiation is begun. Excessive load may also prevent accessory attachments, such as shunt trips or undervoltage releases, from causing the operating mechanism to trip when appropriate.
In conventional practice, a circuit breaker is assembled and the latch load is measured to ensure that it falls within specified limits. The range of these limits tends to be rather wide in order to increase manufacturing yield. If the latch load is out of specification, the usual remedy is to substitute a new trip bar bias spring and/or manually stretch the bias spring, bend it, or cut one or more coil turns from it. In some cases, the circuit breaker trip bar is replaced or scrapped. These remedies all require a certain degree of disassembly and are costly in terms of labor and materials.
One known trip bar includes pivot pockets that receive pivot points on side plates of the circuit breaker. After repeated operation, the pivot pocket can become worn and distorted, thereby shifting the location of the latch relative to the trigger.
There is a need, therefore, for a way to reduce wear in the pivot pockets of the circuit breaker trip bar to improve the operating life of the trip bars.
SUMMARY OF THE INVENTION
An electrical circuit breaker comprises a housing; separable contacts housed within the housing and moveable between a closed position and an open position; an operating means for moving the separable contacts between the closed position and the open position thereof, the operating means having a first position and a second position corresponding to the open position of the separable contacts; a latch for latching the operating means in the first position thereof and for releasing the operating means to the second position thereof; a trip bar movable in a first direction and a second direction for unlatching the latch, the trip bar including first and second pivot pockets for pivotally mounting the trip bar within the housing; a sensor for sensing an electrical condition associated with the separable contacts and for moving the trip bar in the second direction in order to unlatch the latch, to release the operating means to the second position thereof, and to move the separable contacts to the open position thereof, and first and second clips respectively positioned in the first and second pivot pockets for providing bearing surfaces in the trip bar.
BRIEF DESCRIPTION OF THE DRAWINGS
A full understanding of the invention can be gained from the following description of the preferred embodiment when read in conjunction with the accompanying drawings in which:
FIG. 1 is a vertical sectional view of a prior art molded case circuit breaker;
FIG. 2 is an exploded isometric view, with some parts not shown for clarity, of the trip bar mounting assembly of FIG. 1;
FIG. 3 an exploded isometric view of the trip bar constructed in accordance with the preferred embodiment of the present invention; and
FIG. 4 is a cross-sectional view of the trip bar of FIG. 3 taken in the vicinity of a pivot point of an end plate of a circuit breaker.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 shows a molded case three phase circuit breaker 20' as described in U.S. Pat. No. 5,705,968, that comprises an insulated housing 22, formed from a molded base 24 and a molded cover 26, assembled at a parting line 28, although the principles of the present invention are applicable to various types of electrical switching devices and circuit interrupters.
The circuit breaker 20' also includes at least one pair of separable main contacts 30 per phase, provided within the housing 22, which includes a fixed main contact 32 and a movably mounted main contact 34. The fixed contact 32 is carried by a line side conductor 36, electrically connected to a line side terminal (not shown) for connection to an external circuit (not shown). A movably mounted main contact arm assembly 58 carries the movable contact 34 and is electrically connected to a load conductor 66 by way of a plurality of flexible shunts 70. A free end (not shown) of a load conductor 78 connected to the load conductor 66 acts as a load terminal for connection to an external load, such as a motor.
An electronic trip unit 72' includes, for each phase, a current transformer (CT) 74 for sensing load current. The CT 74 is disposed about the load conductor 78 and, in a manner well known in the art, detects current flowing through the separable contacts 30 in order to provide a signal to the trip unit 72' to trip the circuit breaker 20' under certain conditions, such as a predetermined overload condition. The trip unit 72' includes a trip bar 80' and a latch assembly 86. The trip bar 80' has an integrally formed extending trip lever 82 (shown in FIG. 2) mechanically coupled to an undervoltage trip assembly (not shown) which cooperates to rotate the trip bar 80' clockwise (with respect to FIG. 1) during predetermined levels of overcurrent.
The latch assembly 86 latches the operating mechanism 88 during conditions when the circuit breaker 20' is in an ON position (shown in solid in FIG. 1) and a non-trip OFF position (partially shown in phantom line drawing with the arm assembly 58). During an overcurrent condition, the trip unit 72', and more specifically the trip bar 80', releases the latch assembly 86 to allow the circuit breaker 20' to trip. The latch assembly 86 includes a reset plate 90, a pivotally mounted lock plate 92, a latch lever trigger assembly 94, and a biasing spring 96. The lock plate 92 is pivotally mounted to a pair of spaced apart side plates 98 and 99 (both are shown in FIG. 2), used to carry the operating mechanism 88, by way of a pin 101. The reset plate 90 is coupled to the lock plate 92 at one end. The other end of the lock plate 92 is mounted for arcuate movement within the side plates 98, 99. The lock plate 92 includes a pair of spaced apart notches (not shown) for latching a cradle mechanism 104 that forms a portion of the operating mechanism 88. The biasing spring 96 biases the reset plate 90 and the lock plate 92 counterclockwise (with respect to FIG. 1).
The operating mechanism 88 has a latched position (shown in solid in FIG. 1) provided by the latch assembly 86. Upon clockwise rotation of the trip bar 80', an insert 152 (shown in FIG. 2) beneath a latch lever 84 (shown in FIG. 2), integrally formed on the trip bar 80', releases the trigger assembly 94. In turn, the trigger assembly 94 releases the latch assembly lock plate 92 which, in turn, releases the operating mechanism 88 to the unlatched position thereof (partially shown in phantom line drawing in FIG. 1 with the cradle mechanism 104) in order to move the separable contacts 30 to the trip open position thereof, thereby allowing the circuit breaker 20' to trip.
The trigger assembly 94 is pivotally mounted to one of the side plates 99 by the pin 100 and is biased in a counterclockwise direction (with respect to FIG. 1) by a torsion spring (not shown). A stop pin 108 serves to limit rotation of the trigger assembly 94. The trigger assembly 94 is integrally formed with an upper latch portion 110 and a lower latch portion 112. The lower latch portion 112 is adapted to engage the lock plate 92. The upper latch portion 110 is adapted to communicate with the insert 152 (shown in FIG. 2) of the trip bar 80'.
The operating mechanism 88 moves the separable main contacts 30 between the closed and open positions thereof and, thus, facilitates opening and closing the separable contacts 30. The operating mechanism 88 includes a toggle assembly 114 which has a pair (only one is shown in FIG. 1) of upper toggle links 116 and a pair (only one is shown in FIG. 1) of lower or trip links 118. Each of the upper toggle links 116 receives a crossbar 126 and is provided with a hole 128' that allows it to be mechanically coupled to the cradle mechanism 104 by way of a pin 130. Operating springs 132 are connected between the crossbar 126 and a handle yoke assembly 134 by way of spring retainers 136.
The cradle mechanism 104 is pivotally connected to the side plates 98, 99 by way of a pin 106. The cradle mechanism 104, in cooperation with the latch assembly 86, allows the circuit breaker 20' to be tripped by way of the trigger assembly 94 of the trip unit 72'. In order to reset the cradle mechanism 104, it is necessary to rotate the operating handle 140 toward the off position (shown in phantom line drawing in FIG. 1). The operating handle 140, in cooperation with the handle yoke 134 and a reset pin 142 driven by the yoke 134, allows the cradle mechanism 104 to be moved clockwise (with respect to FIG. 1) and latched relative to the latch assembly 86.
The housing 22, separable contacts 30, operating mechanism 88, operating handle 140 and handle yoke 134, and trip unit 72' excluding the trip bar 80' are disclosed in greater detail in U.S. Pat. No. 5,341,191. The present invention provides improvements disclosed herein in connection with the trip bar 80'.
The trip bar 80' is rotatable in the counterclockwise direction under the bias of the mechanism 144 and in the clockwise direction as discussed above. The trip unit 72' senses an electrical condition, such as an overcurrent condition, associated with the separable contacts 30 and rotates the trip bar 80' in the clockwise rotational direction in order to unlatch the latch assembly 86, release the operating mechanism 88 to the unlatched position thereof, and move the separable contacts 30 to the open position thereof, although the invention is applicable to a wide range of such sensed electrical conditions (e.g., an undervoltage condition, a trip condition detected by an external shunt trip device which remotely trips the circuit breaker 20').
FIG. 2 illustrates the exemplary plastic molded trip bar 80' of the trip unit 72' of FIG. 1 and the adjustable bias spring mechanism 144 having an adjustable helical compression bias spring 146. The elongated trip bar 80' has a transverse member or paddle 148. The paddle 148 is the point of actuation of the bias spring 146 upon the trip bar 80' which is biased by the spring 146 in the counterclockwise direction (with respect to FIG. 2). The elongated spring 146 is generally normal to the trip bar 80'. The trip bar 80' also has the insert 152 (shown in FIG. 2), which is engaged by the latch assembly 86 of FIG. 1, and the trip lever 82, which is engaged by a plunger, such as a trip pin plunger (not shown), to rotate the trip bar 80' in the clockwise direction (with respect to FIG. 2) in order to unlatch the latch assembly 86. The exemplary steel latch insert 152 is assembled into a diametrical hole in the trip bar 80'. Two recesses 156 (best shown in FIG. 3) retain the trip bar 80' axially in the side plates 98, 99 which provide pivot points 158 for rotation of the trip bar 80' on side plate ears 160.
An internal deck or molded housing member 162 of the housing 22 of FIG. 1 has an opening 164. A threaded insert 166 is rigidly pressed into the opening 164 or is suitably molded into place in the deck 162. A portion of the bias spring 146 engages the internal thread of the insert 166 at about the opening 164 of the deck 162. The exemplary bias spring 146 has a major diameter 168 and a minor diameter 170 with a spring end 172 turned in toward the center of the body of the minor diameter 170. Preferably, the wire size and minor diameter 170 of the bias spring 146 are selected to allow such diameter 170 to wind snugly into the internal thread of the insert 166, with the pitch of the diameter 170 being slightly shorter than the pitch of the internal thread. The trip bar 80' is assembled into the two side plates 98, 99 supported by the side plate ears 160. The deck 162, the bias spring 146 and the insert 166 are assembled over the trip bar 80' and side plates 98, 99 in order that the end of the major diameter 168 of the bias spring 146 engages the paddle 148 of the trip bar 80'. Still referring to FIG. 2, the minor diameter upper portion 170 of the spring 146 is biased with respect to and engages the insert 166 of the deck 162 at about the opening 164 thereof. The lower portion 168 of the spring 146 engages and biases the paddle 148 of the trip bar 80'. The upper spring end 172 forms a cross member adjacent the opening 164 of the deck 162. The cross member is rotatable by a suitable adjustment member (not shown) through the opening 164 in order to adjust the length of the bias spring 146 and, hence, the bias on the paddle 148 of the trip bar 80'.
Referring again to FIG. 2, the forces involved in determining latch load are illustrated. The latch load is typically measured as the force, F TRIP , required by a test probe (not shown) at trip lever 82 (i.e., the actuation point of accessory attachments to the circuit breaker 20' of FIG. 1) on the trip bar 80' to cause the clockwise torque about the axial centerline of the trip bar 80' necessary to release the trigger assembly 94. There are three other torques present on the trip bar 80' during a tripping action. First, there is a counterclockwise torque, F FRICTION , resisting clockwise rotation of the trip bar 80' due to friction between the trip bar 80' and the side plates 98, 99 at the pivot points 158. In prior art circuit breakers, a tetrafluoroethylene (which is sold under the trade designation, "Teflon") based grease or another suitable lubricant has been employed in the recesses 156 of the trip bar 80' to minimize friction at the pivot points 158. The second torque is due to the load, F TRIGGER , imposed by the trigger assembly 94 on the latch insert 152. This is a clockwise torque, tending to push the trip bar 80' "off latch". Preferably, this clockwise torque is minimized to reduce shock-outs. The force F TRIGGER is dependent upon many variables within the operating mechanism 88 of FIG. 1 (e.g., toggle spring force, parts tolerance) which are normal manufacturing variables. The third torque imposed on the trip bar 80' is counterclockwise due to the force, F SPRING , of the bias spring 146 acting on the paddle 148. It will be appreciated by those skilled in the art that, of these three torques, the most controllable is that due to the adjustable bias spring 146 of the invention. This is typically done by adjusting the length of the bias spring 146. The cross member of the turned-in spring end 172 allows a suitable adjusting tool (not shown) to grab the bias spring 146 and rotate it within the threaded insert 166. Since the spring pitch is slightly undersized relative to the pitch of the threaded insert 166, rotation of the bias spring 146 causes it to wind itself into and/or out of the insert 166 and to extend the length of such spring 146 slightly at the minor diameter end 170. This extension in the minor diameter 170 induces friction between the wire of the spring 146 and the internal thread of the insert 166 to prevent the adjustment from changing during normal operation of the circuit breaker 20'. Increasing (decreasing) the free length of the bias spring 146 between the assembly formed by the deck 162, the threaded insert 166 and the trip bar paddle 148 causes the load between such spring 146 and the trip bar paddle 148, F SPRING , to increase (decrease) proportionally. The force F SPRING directly affects torque on the trip bar 80'. An assembly operator is then able to adjust the spring load and measure (e.g., using a load cell) latch load resulting from that change.
FIG. 3 an exploded isometric view of the trip bar 80" constructed in accordance with the preferred embodiment of the present invention. Trip bar 80" is preferably made of an insulating material to prevent the conduction of electric current between internal parts of the circuit breaker. In the preferred embodiment of the invention, the trip bar is a compression molded glass reinforced plastic material. Although compression molded glass reinforced plastic is a relatively wear resistant material, repeated movement of the trip bar about the pivot points on the circuit breaker side plates can result in wear of the pivot pockets in the trip bar. Such wear can result in the trip bar being displaced from its normal operating position, thereby affecting performance of the trip mechanism. In order to reduce wear in the pivot pockets 156 of the trip bar, metal clips 174, which are shaped to fit within the pivot pockets, are installed on the trip bar 80". The metal clips are preferably made of cold rolled steel and include inward facing flanges 176 at each end to latch onto the trip bar. The clips preferably have spring characteristics so that they clamp onto the trip bar when installed. The metal clips are significantly harder than the glass reinforced plastic that comprises the body of the trip bar.
FIG. 4 is a cross-sectional view of the trip bar 80" of FIG. 3 taken in the vicinity of a pivot point of an end plate of a circuit breaker. FIG. 4 shows that the spring clips 174 make contact with the pivot point 158, thereby preventing contact between the pivot point and the glass reinforced plastic used to make the trip bar 80". The flanges 176 on the clips lock into recesses in the trip bar to secure the clips to the trip bar. The frictional force F FRICTION acts on the clip, not on the glass reinforced plastic. Since the clips provide the bearing surface for the side plate pivot points, and are harder that the glass reinforced plastic of the body of the trip bar, this substantially reduces wear in the pivot pockets of the trip bar.
While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof. | An electrical circuit breaker comprises a housing; separable contacts housed within the housing and moveable between a closed position and an open position; an operating mechanism for moving the separable contacts between the closed position and the open position thereof, the operating mechanism having a first position and a second position corresponding to the open position of the separable contacts; a latch for latching said operating mechanism in the first position thereof and for releasing the operating mechanism to the second position thereof; a trip bar movable in a first direction and a second direction for unlatching said latch, the trip bar including first and second pivot pockets for pivotally mounting the trip bar within the housing; a sensor for sensing an electrical condition associated with the separable contacts and for moving the trip bar in the second direction in order to unlatch the latch, to release the operating mechanism to the second position thereof, and to move the separable contacts to the open position thereof; and first and second clips respectively positioned in the first and second pivot pockets for providing bearing surfaces in the trip bar. | 7 |
TECHNICAL FIELD OF THE INVENTION
[0001] This invention relates, in general, to completing a well that traverses a hydrocarbon bearing subterranean formation and, in particular, to a system and method for creating a fluid seal between production tubing and well casing by expanding a section of the production tubing having seal elements positioned therearound.
BACKGROUND OF THE INVENTION
[0002] Without limiting the scope of the present invention, its background will be described with reference to producing fluid from a subterranean formation, as an example.
[0003] After drilling each of the sections of a subterranean wellbore, individual lengths of relatively large diameter metal tubulars are typically secured together to form a casing string that is positioned within each section of the wellbore. This casing string is used to increase the integrity of the wellbore by preventing the wall of the hole from caving in. In addition, the casing string prevents movement of fluids from one formation to another formation. Conventionally, each section of the casing string is cemented within the wellbore before the next section of the wellbore is drilled. Accordingly, each subsequent section of the wellbore must have a diameter that is less than the previous section.
[0004] For example, a first section of the wellbore may receive a conductor casing string having a 20-inch diameter. The next several sections of the wellbore may receive intermediate casing strings having 16-inch, 13⅜-inch and 9⅝-inch diameters, respectively. The final sections of the wellbore may receive production casing strings having 7-inch and 4½-inch diameters, respectively. Each of the casing strings may be hung from a casing head near the surface. Alternatively, some of the casing strings may be in the form of liner strings that extend from near the setting depth of previous section of casing. In this case, the liner string will be suspended from the previous section of casing on a liner hanger.
[0005] Once this well construction process is finished, the completion process may begin. The completion process comprises numerous steps including creating hydraulic openings or perforations through the production casing string, the cement and a short distance into the desired formation or formations so that production fluids may enter the interior of the wellbore. In addition, the completion process may involve formation stimulation to enhance production, gravel packing to prevent sand production and the like. The completion process also includes installing a production tubing string within the well that extends from the surface to the production interval or intervals. Unlike the casing strings that form a part of the wellbore itself, the production tubing string is used to produce the well by providing the conduit for formation fluids to travel from the formation depth to the surface.
[0006] Typically, a production packer is run into the well on the production tubing string. The purpose of the packer is to support production tubing and other completion equipment, such as a screen adjacent to a producing formation, and to seal the annulus between the outside of the production tubing and the inside of the well casing to block movement of fluids through the annulus past the packer location. Conventionally, the packer is provided with anchor slips having opposed camming surfaces which cooperate with complementary opposed wedging surfaces, whereby the anchor slips are radially extendible into gripping engagement against the interior of the well casing in response to relative axial movement of the wedging surfaces.
[0007] The packer also carries annular seal elements which are expandable radially into sealing engagement against the interior of the well casing in response to axial compression forces. The longitudinal movement of the packer components required to set the anchor slips and the sealing elements may be produced either hydraulically or mechanically.
[0008] After the packer has been set and sealed against the well casing, this sealing engagement will typically remain even upon removal of the hydraulic or mechanical setting force. In fact, it is essential that the packer remain locked in its set and sealed configuration such that it can withstand hydraulic pressures applied externally or internally from the formation and/or manipulation of the production tubing string and service tools without unsetting or interrupting the seal.
[0009] It has been found, however, that to provide the required sealing and gripping capabilities, conventional packers have become quite complex. In addition, it has been found that due to the complexity of conventional packers, the cost of conventional packers is quite high. Further, it has been found that even with the complexity of conventional packers, some conventional packers fail to provide the necessary sealing and/or gripping capability after installation.
[0010] A need has therefore arisen for a system and method for creating a fluid seal between production tubing and well casing that does not require a complex conventional packer. A need has also arisen for such a system and method that are capable of reducing the cost typically associated with manufacturing a conventional packer. Further, a need has arisen for such a system and method that provide for improved sealing and gripping capabilities upon installation.
SUMMARY OF THE INVENTION
[0011] The present invention disclosed herein comprises a system and method for creating a fluid seal between production tubing and well casing that does not require a complex conventional packer. The system and method of the present invention are capable of reducing the cost typically associated with manufacturing a conventional packer. In addition, the system and method of the present invention provide for improved sealing and gripping capabilities upon installation.
[0012] The well completion system for creating a seal between a production tubing and a well casing of the present invention comprises a production packer including a section of the production tubing and at least one seal element and an expander member positioned within the production tubing that travels longitudinally through the production packer to expand the section of the production tubing downhole, thereby creating the seal between the production tubing and the well casing. The expander member may travel longitudinally within the production packer from an uphole location to a downhole location or from a downhole location to an uphole location.
[0013] The expander member may be urged to travel longitudinally within the production packer by pressurizing at least a portion of the production tubing. Alternatively, coiled tubing may be coupled to the expander member. In this case, the expander member may be urged to travel longitudinally within the production packer by pressurizing the coiled tubing and at least a portion of the production tubing, by pulling the coiled tubing or both. Prior to pressurizing the portion of the production tubing a plug may be set within the production tubing to seal the pressure within the production tubing that acts on the expander member. Alternatively, the expander member may be urged to travel longitudinally within the production packer by pushing on the coiled tubing to compress the expander member then pressurizing the coiled tubing and an interior section of the expander member to urge the expander member to travel longitudinally within the production packer.
[0014] Following the expansion of the production packer and during the same trip downhole, a treatment fluid may be pumped downhole and through a cross-over assembly operably associated with the expander member such that the treatment fluid is delivered into an annulus between the production tubing and the well casing downhole of the production packer. The treatment preformed may be a fracture treatment, a gravel pack, a frac pack or the like. Following the treatment process, the expander member may be retrieved to the surface by decoupling a work string, carrying the expander member and the cross-over assembly, from the production tubing that is now fixed within the casing.
[0015] Broadly stated, the method of the present invention involves lining the wellbore with the well casing, disposing a production packer including a section of the production tubing and at least one seal element within the well casing and setting the production packer downhole by radially expanding the section of the production tubing, thereby creating the seal between the production tubing and the well casing.
[0016] The method of the present invention may also involve lining the wellbore with the well casing, positioning an expander member and a plug within the production tubing, disposing a production packer including a section of the production tubing and at least one seal element within the well casing, coupling a coiled tubing to the expander member, installing the plug within the production tubing, pressurizing the coiled tubing and at least a portion of the production tubing between the plug and the expander member, urging the expander member to travel longitudinally within the production packer, creating the seal between the production tubing and the well casing, retrieving the coiled tubing and the expander member uphole and retrieving the plug uphole.
[0017] Likewise, the method of the present invention may involve disposing a production packer including a section of a production tubing and at least one seal element within a well casing, setting the production packer downhole by radially expanding the section of the production tubing to create a seal between the production tubing and the well casing and pumping a treatment fluid through a cross-over assembly into an annulus between the production tubing and the well casing downhole of the production packer.
[0018] Once an expandable production packer of the present invention is installed, it may become necessary to remove the expandable production packer of the present invention from its sealing relationship with the well casing. One method for releasing an expandable production packer of the present invention involves positioning a release member within the expandable production packer such that first and second end sections of the release member are on opposite sides of the seal element of the expandable production packer and operating the release member such that the diameter of the seal element is reduced, thereby releasing the seal element from contact with the well casing.
[0019] This reduction may be achieved by elongating the expandable production packer, by generating a radially inwardly acting collapse force due to a differential pressure between the interior and the exterior of the expandable production packer or both. In those embodiments wherein the collapse force is utilized, this operation may be enhanced by weakening the expandable production packer behind the seal element. This weakening process may be achieved chemically, mechanically, thermally, explosively or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures in which corresponding numerals in the different figures refer to corresponding parts and in which:
[0021] [0021]FIG. 1 is a schematic illustration of an offshore oil and gas platform installing an expandable production packer according to the present invention;
[0022] [0022]FIG. 2 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string;
[0023] [0023]FIG. 3 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string after installation of a plug;
[0024] [0024]FIG. 4 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string prior to expansion;
[0025] [0025]FIG. 5 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string during expansion;
[0026] [0026]FIG. 6 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string prior to expansion;
[0027] [0027]FIG. 7 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string during expansion;
[0028] FIGS. 8 A- 8 B are a half sectional views of an expander member for use in expanding the expandable production packer according to the present invention in its contacted and expanded positions, respectively;
[0029] [0029]FIG. 9 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string prior to expansion;
[0030] [0030]FIG. 10 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string during expansion;
[0031] [0031]FIG. 11 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string after expansion and during a well treatment process;
[0032] [0032]FIG. 12 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string after completion of the well treatment process and retrieval of the work string;
[0033] [0033]FIG. 13 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string and having a release member positioned therein prior to the release operation;
[0034] [0034]FIG. 14 is a half sectional view of an expandable production packer according to the present invention that has been released from a casing string using a release member;
[0035] [0035]FIG. 15 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string and having a release member positioned therein prior to the release operation;
[0036] [0036]FIG. 16 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string and having a release member positioned therein prior to the release operation;
[0037] [0037]FIG. 17 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string and having a release member positioned therein prior to the release operation;
[0038] [0038]FIG. 18 is a half sectional view of an expandable production packer according to the present invention that is positioned within a casing string and having a radial cutting tool positioned; and
[0039] [0039]FIG. 19 is a half sectional view of an expandable production packer according to the present invention that has been released from a casing string.
DETAILED DESCRIPTION OF THE INVENTION
[0040] While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts which can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention, and do not delimit the scope of the present invention.
[0041] Referring initially to FIG. 1, an expandable production packer of the present invention is being installed from an offshore oil and gas platform that is schematically illustrated and generally designated 10 . A semi-submersible platform 12 is centered over a submerged oil and gas formation 14 located below sea floor 16 . A subsea conduit 18 extends from deck 20 of platform 12 to wellhead installation 22 including subsea blow-out preventers 24 . Platform 12 has a hoisting apparatus 26 and a derrick 28 for raising and lowering pipe strings such as production tubing string 30 .
[0042] A wellbore 32 extends through the various earth strata including formation 14 . A casing 34 is cemented within wellbore 32 by cement 36 . Production tubing string 30 is coupled on its lower end to various tools including sand control screen assemblies 38 , 40 , 42 positioned adjacent to formation 14 and perforations 44 below expandable production packer 46 .
[0043] As explained in greater detail below, to provide a seal between casing 34 and production tubing 30 , expandable production packer 46 may be expanded. Accordingly, production tubing 30 includes, above and below expandable production packer 46 of the present invention, a launcher 52 and a catcher 54 between which an expander member 56 longitudinally travels to plastically deform expandable production packer 46 . In the illustrated embodiment, this is achieved by pressurizing production tubing string 30 between a plug 58 and the lower end of expander member 56 by pumping fluid down through a work string such as a jointed tubing string or, as illustrated, a coiled tubing string 59 that is coupled to expander member 56 .
[0044] Referring now to FIGS. 2 - 5 , therein are depicted more detailed views of one method for creating a fluid seal between production tubing 30 and well casing 34 with an expandable production packer 46 . Expandable production packer 46 includes a plurality of seal elements 60 A- 60 E that are positioned around an expandable section of tubing string 30 . Once the expansion process is performed, seal elements 60 A- 60 E are placed in intimate contact with the interior wall of casing 34 to provide a sealing and gripping arrangement between production tubing 30 and casing 34 . To achieve this expansion, production tubing 30 includes launcher 52 and catcher 54 . Initially disposed within launcher 52 is expander member 56 .
[0045] It should be noted, however, by those skilled in the art that instead of installing production tubing string 30 in casing string 34 with expander member 56 already positioned within launcher 52 , an expander member could alternatively be run in after production tubing string 30 has been installed within casing string 34 . In this case, it may be necessary that the expander member have a smaller diameter running configuration such that it may be run in production tubing string 30 and through expandable production packer 46 prior to expansion and a larger diameter expansion configuration suitable for expanding expandable production packer 46 as described below.
[0046] In the illustrated embodiment, expander member 56 has a tapered cone section 62 which includes a receiver portion that is coupled to the lower end of coiled tubing string 59 . Initially, expander member 56 is coupled within launcher 52 by a shear pin (not pictured) or other suitable device that holds expander member 56 within launcher 52 but allows the release of expander member 56 as required. Also initially, plug 58 may be attached to the lower end of expander member 56 , as best seen in FIG. 2. Once coiled tubing string 59 is coupled to expander member 56 , a longitudinal force may be applied to expander member 56 to release expander member 56 from attachment with launcher 52 . Thereafter, coiled tubing string 59 , together with expander member 56 and plug 58 may be lowered downhole until plug 58 is located within landing nipple 64 , as best seen in FIG. 3. Plug 58 is then released from expander member 56 and coiled tubing string 59 , together with expander member 56 is raised uphole until expander member 56 is within launcher 52 , as best seen in FIG. 4.
[0047] The diameter of the section of production tubing string 30 within expandable production packer 46 may now be increased by moving expander member 56 longitudinally through expandable production packer 46 from launcher 52 to catcher 54 . As best seen in FIG. 5, a fluid is pumped down coiled tubing string 59 into the portion of production tubing string 30 between plug 58 and the lower end of expander member 56 , as indicated by arrows 66 . The fluid pressure urges expander member 56 upwardly such that tapered cone section 62 of expander member 56 contacts the interior wall of expandable production packer 46 . As the fluid pressure increases, tapered cone section 62 applies a radially outward force to the wall of expandable production packer 46 . When this force is sufficient to plastically deform expandable production packer 46 , expander member 56 begins to travel longitudinally within expandable production packer 46 .
[0048] As the upward movement of expander member 56 progresses, expandable production packer 46 substantially uniformly expands from its original diameter to a diameter similar to the diameter of expander member 56 . As this expansion occurs, seal elements 60 A- 60 E progressively expand into intimate contact with casing 34 . Once seal elements 60 A- 60 E are expanded, a fluid seal is created between production tubing 30 and casing 34 . In addition, seal elements 60 A- 60 E anchor production tubing 34 within casing 34 . Seal elements 60 A- 60 E may be constructed from a polymeric material such as rubber or other non-metallic materials or may be constructed from a metal such as lead or other suitable material that can expand radially when the production tubing about which it is attached is expanded and that can provide a suitable fluid seal and gripping force against the interior of casing 34 . In addition, it should be understood by those skilled in the art that even though FIGS. 2 - 5 have depicted five seal elements 60 A- 60 E attached to a section of production tubing 30 to form production packer 46 , other numbers of seal elements both greater than and less than five could alternatively be used without departing from the principles of the present invention. In fact, a significant advantage of the production packers of the present invention is that numerous independent seal elements may be placed along one or more sections of the production tubing string which not only improves the reliability of the seal between the production tubing and the well casing but also improves the anchoring capability as the anchoring force is spread across a large area.
[0049] In addition, as seal elements 60 A- 60 E provide both sealing and anchoring capabilities, the slips typically associated with production packers are not required, which, among other things, significantly reduces the complexity and cost of expandable production packers 46 of the present invention versus conventional production packers. If additional anchoring capability is desired with expandable production packers 46 , however, the outer surface of the section of tubing string 30 of expandable production packer 46 may be serrated to increase the friction between expandable production packer 46 and the inner surface of casing 34 .
[0050] It should be noted by those skilled in the art that the force necessary to plastically deform expandable production packer 46 is dependant upon a variety of factors including the ramp angle of tapered cone section 62 , the amount of the desired expansion of expandable production packer 46 , the material of expandable production packer 46 and the like. Since only a short section of expandable production packer 46 is being expanded at any one time, however, the fluid pumped through coiled tubing string 59 typically provides sufficient upward force to expander member 56 to expand that section of expandable production packer 46 . This force may be controlled by adjusting the flow rate and pressure at which the fluid is delivered through coiled tubing string 59 .
[0051] The upward force of expander member 56 may be enhanced by pulling on expander member 56 , which may be accomplished by placing coiled tubing string 59 in tension. In fact, longitudinal movement of expander member 56 may be achieved completely mechanically by pulling expander member 56 through expandable production packer 46 by placing coiled tubing string 59 in sufficient tension. In this case, since no fluids are used to upwardly urge expander member 56 , no plug 58 below catcher 52 is necessary. In the illustrated embodiment, once the expansion process is complete, coiled tubing string 59 , expander member 56 and plug 58 may be retrieved to the surface. For example, expander member 56 may be returned to its runing configuration such that expander member 56 may travel back through expandable production packer 46 and be coupled to plug 58 prior to retrieval to the surface. Alternatively, coiled tubing string 59 and expander member 56 may be retrieved to the surface together and, thereafter, plug 58 may be retrieved by wireline or other suitable techniques.
[0052] It should be apparent to those skilled in the art that the use of direction terms such as above, below, upper, lower, upward, downward and the like are used in relation to the illustrated embodiments as they are depicted in the figures, the upward direction being toward the top of the corresponding figure and the downward being toward the bottom of the corresponding figure. Accordingly, it should be noted that the expandable production packer of the present invention and the methods for setting the expandable production packer of the present invention are not limited to the vertical orientation as they are equally well suited for use in inclined, deviated and horizontal wellbores.
[0053] While FIGS. 1 - 5 have depicted the expansion of expandable production packer 46 as progressing from a downhole location to an uphole location, the expansion could alternatively progress from an uphole location to a downhole location, as best seen in FIGS. 6 and 7. Specifically, production tubing string 70 is disposed within wellbore 32 having casing string 34 cemented therein with cement 36 . Disposed within production tubing string 70 is expandable production packer 72 including a plurality of seal elements 74 A- 74 E position around a section of production tubing string 70 . Above expandable production packer 72 is a launcher 76 into which an expander member 78 is placed. Expander member 78 includes a tapered cone section 80 , a piston 82 and an anchor section 84 . Anchor section 84 includes a receiver portion that is coupled to the lower end of coiled tubing string 86 .
[0054] In operation, a downward force is placed on expander member 78 by applying the weight of coiled tubing string 86 on expander member 78 . This downward force operates to stroke piston 82 to its compressed position, as best seen in FIG. 7. Once piston 82 completes its downward stroke, fluid is pumped down coiled tubing string 86 which sets anchor section 84 creating a friction grip between anchor section 84 and the interior of expandable production packer 72 which prevents upward movement of anchor section 84 . More fluid is then pumped down coiled tubing string 86 , as indicated by arrow 88 , which urges tapered cone section 80 downwardly such that tapered cone section 80 places a radially outward force against the wall of expandable production packer 72 causing expandable production packer 72 to plastically deform creating a sealing and gripping connection between production tubing 70 and casing 34 with seal elements 74 A- 74 E. This process continues in a step wise fashion wherein each stroke of expander member 78 expands a section of expandable production packer 72 . After expandable production packer 72 has been expanded and expander member 78 has been returned to its running configuration, coiled tubing string 86 and expander member 78 may be retrieved to the surface.
[0055] Referring now to FIGS. 8 A- 8 B, therein are depicted more detailed views of expander member 78 in its expansion configuration and in its fully contracted and fully extended positions, respectively. Expander member 78 includes a tapered cone section 80 , a piston 82 and an anchor section 84 . Anchor section 84 includes a receiver portion 81 that may be coupled to the lower end of coiled tubing string 86 (not pictured). Anchor section 84 includes fluid ports 79 , coiled spring 83 and slips 85 that cooperate together such that when a fluid pressure is applied within expander member 78 and into fluid ports 79 , coiled spring 83 is compressed causing slips 85 to outwardly radially expand and grip the interior of expandable production packer 72 (not pictured). In addition, the fluid pressure acts on piston 82 on surface 86 and surface 87 , via fluid ports 88 , such that the force of the fluid pressure is multiplied. This force acting on piston 82 causes piston 82 , along with tapered cone section 80 , to be downwardly urged toward the position depicted in FIG. 8B. Once expander member 78 has completed its stroke and expanded a length of expandable production packer 72 (not pictured), the fluid pressure in expander member 78 is allowed to bleed off such that expander member 78 may be collapsed back to the configuration depicted in FIG. 8A and another stoke of expander member 78 may begin.
[0056] Referring now to FIGS. 9 - 12 , therein is depicted another embodiment of a method for creating a fluid seal between production tubing and casing with an expandable production packer and treating a wellbore. Production tubing string 90 is disposed within wellbore 92 having a casing string 94 that is cemented within wellbore 92 with cement 96 . Tubing string 90 includes expandable production packer 96 having seal elements 98 A- 98 C. Tubing string 90 also includes treatment fluid ports 100 that are positioned downhole of expandable production packer 96 , return fluid ports 102 that are positioned uphole of expandable production packer 96 , a latch member 104 and a launcher 106 . A work string 108 having a latch member 110 is coupled to tubing string 90 at latch member 104 . Disposed within tubing string 90 and work string 108 is an expander member 112 . Expander member 112 includes a tapered cone section 114 , a cross-over section 116 and a piston section 118 . Disposed between expander member 112 and tubing string 90 is a plurality of seals 120 carried on expander member 112 to provide fluid sealing therebetween.
[0057] In operation, once tubing string 90 is properly positioned within casing 94 with expander member 112 therein, a fluid is pumped down work string 108 as indicated by arrows 122 . As best seen in FIG. 10, the fluid pressure urges tapered cone section 114 downwardly placing a radially outward force against the wall of expandable production packer 96 causing expandable production packer 96 to plastically deform creating a sealing and gripping connection between tubing string 90 and casing 94 with seal elements 98 A- 98 C. This process continues until piston section 118 reaches it full travel against shoulder 124 , as best seen in FIG. 11.
[0058] At this point, seal elements 98 A- 98 C of expandable production packer 96 provide a seal between production tubing 90 and casing 94 . Also, cross-over section 116 traverses expandable production packer 96 with portions of cross-over assembly 154 on either side of packer 96 . As illustrated, when the treatment operation is a frac pack, the objective is to enhance the permeability of formation 14 (see FIG. 1) by delivering a fluid slurry containing proppants at a high flow rate and in a large volume above the fracture gradient of the formation such that fractures may be formed within the formation and held open by the proppants. In addition, a frac pack also has the objective of preventing the production of fines by packing the annulus between sand control screens 38 , 40 , 42 (see FIG. 1) and casing 34 with the proppants. To help achieve these results, a valve at the surface is initially in the closed position to prevent the flow of return fluids.
[0059] The fluid slurry containing proppants is then pumped down work string 108 and expander member 112 as indicated by arrows 130 . In the illustrated embodiment, the fluid slurry containing proppants exits expander member 112 and enters annulus 132 between casing 94 and production tubing 90 , via treatment fluid ports 100 . As the fluid slurry containing proppants is being delivered at a high flowrate and in a large volume above the fracture gradient of formation 14 and as no returns are initially taken, the fluid slurry fractures formation 14 . It should be noted that as the frac pack operation progresses some of the proppants in the fluid slurry screens out in annulus 132 , thereby packing annulus 132 around sand control screens 38 , 40 , 42 . This packing process may be enhanced by reducing the flow rate of the fluid slurry toward the end of the treatment process and opening the surface valve to allow some returns to flow to the surface.
[0060] Specifically, when the surface valve is opened, the liquid carrier of the fluid slurry containing proppants is allowed the travel through sand control screens 38 , 40 , 42 while the proppants are disallowed from traveling through sand control screens 38 , 40 , 42 . Accordingly, the proppants become tightly packed in annulus 132 . The return fluids, as indicated by arrows 134 , travel up tubing string 90 into expander member 112 . Return fluids 134 then travel through a micro-annulus 136 within expander member 112 and return fluid ports 102 before entering annulus 138 between work string 108 and casing 94 for return to the surface. It should be noted by those skilled in the art that even though a frac pack operation has been described, expander member 112 is equally well-suited for use in other well treatment operations including fracture operations, gravel pack operations, cementing operations, chemical treatment operations and the like.
[0061] After the process of creating the fluid seal between the casing and the production tubing as well as the process of well treatment is complete, work string 108 along with expander member 112 are retrieved to the surface, as best seen in FIG. 12. This is achieved by releasing latch member 104 of tubing string 90 from latch member 110 of work string 108 . Thereafter, the rest of the production tubing string may be run downhole and attached to tubing string 90 at latch 104 or by other suitable means.
[0062] With all the above described embodiments of the expandable production packer of the present invention, it may be necessary to remove an expandable production packer of the present invention once it has been installed. Accordingly, the present invention provides several methods of releasing an expandable production packer of the present invention for retrieval. Referring now to FIGS. 13 - 14 , therein are depicted one method of releasing an expandable production packer that is designated 150 . Expandable production packer 150 includes a plurality of seal elements 152 A- 152 E that are positioned around an expandable section of tubing string 154 that has previously been expanded using a technique described herein or other suitable technique. As illustrated, seal elements 152 A- 152 E are in intimate contact with the interior wall of casing 156 such that a sealing and gripping arrangement exists between production tubing 154 and casing
[0063] If it becomes necessary to retrieve expandable production packer 150 , the intimate contact of seal elements 152 A- 152 E with the interior of casing string 156 must be released. This is achieved using release member 158 . In the illustrated embodiment, release member 158 includes a pair of latching keys 160 , 162 that respectively match and lock into latch profiles 164 , 166 of tubing string 154 . Release member 158 also includes a piston section 168 and a receiver portion 170 that is coupled to the lower end of coiled tubing string 172 and that provides for fluid communication between coiled tubing string 172 and piston section 168 . Once release member 158 and coiled tubing string 172 are positioned as depicted in FIG. 13, an axially tensile force may be placed on expandable production packer 150 between latch profiles 164 ,
[0064] Specifically, in the illustrated embodiment, a fluid is pumped downhole via coiled tubing string 172 and into piston section 168 placing expandable production packer 150 in tension between latch profiles 164 , 166 . As the pressure increases within piston section 168 , the tensile force becomes sufficient to plastically deform expandable production packer 150 such that the diameter of expandable production packer 150 is reduced. Multiple factors work together to achieve this reduction.
[0065] For example, the tensile force placed on expandable production packer 150 causes elongation in the expandable section of tubing string 154 between latch profiles 164 , 166 . This elongation results in a reduction in the diameter of this section of tubing 154 and accordingly a reduction in the diameter of seal elements 152 A- 152 E. In addition, the diameter of seal elements 152 A- 152 E is further reduced due to the elongations of seal elements 152 A- 152 E themselves. Further, the difference in the diameter of tubing 154 between latch profiles 164 , 166 and the diameter of tubing 154 at latch profiles 164 , 166 cause a radially inward force to act on tubing 154 between latch profiles 164 , 166 while the tensile force is being applied. Accordingly, under sufficient tensile force, the diameter of tubing 154 between latch profiles 164 , 166 is reduced such that the intimate contact between seal elements 152 A- 152 E and the interior of casing string 156 is released, as best seen in FIG. 14. Thereafter, tubing string 154 along with expandable production packer 150 can be retrieved to the surface.
[0066] It should be noted by those skilled in the art that the force necessary to plastically deform expandable production packer 150 and allow release thereof is dependant upon a variety of factors including the difference in the diameter of tubing 154 between latch profiles 164 , 166 and the diameter of tubing 154 at latch profiles 164 , 166 , the amount of expansion originally achieved by expandable production packer 150 , the material of expandable production packer 150 and the like. It should be noted that the tensile force may be controlled by adjusting the fluid pressure delivered through coiled tubing string 172 . Additionally, it should be understood by those skilled in the art that even though FIG. 14 depicts the diameter of tubing 154 between latch profiles 164 , 166 being reduced such that no contact between seal elements 152 A- 152 E and the interior of casing string 156 remains, some contact between one or more of the seal elements 152 A- 152 E and the interior of casing string 156 is acceptable as long as expandable production packer 150 can be retrieved to the surface.
[0067] Referring now to FIG. 15, therein is depicted another method of releasing an expandable production packer that is designated 180 . Expandable production packer 180 includes a plurality of seal elements 182 A- 182 E that are positioned around an expandable section of tubing string 184 that has previously been expanded using a technique described herein or other suitable technique. As illustrated, seal elements 182 A- 182 E are in intimate contact with the interior wall of casing 186 such that a sealing and gripping arrangement exists between production tubing 184 and casing 186 .
[0068] If it becomes necessary to retrieve expandable production packer 180 , the intimate contact of seal elements 182 A- 182 E with the interior of casing string 186 must be released. This is achieved using release member 188 that includes a pair of latching keys 190 , 192 that respectively match and lock into latch profiles 194 , 196 of tubing string 184 . Release member 188 also includes a piston section 198 . Release member 188 may be run downhole on a conveyance 200 such as a jointed tubing, a coiled tubing, a wireline, a slickline, an electric line or the like. Coupled between conveyance 200 and release member 188 is an operating assembly 202 .
[0069] In one embodiment, conveyance 200 is a wireline and operating assembly 202 is a hydraulic pump. In this embodiment, the wireline may be used to stroke the hydraulic pump such that fluid is pumped into piston section 198 , thereby placing an axially tensile force on expandable production packer 180 between latch profiles 194 , 196 which elongates this section of tubing 184 , as described herein, allowing for the release of expandable production packer 180 .
[0070] In another embodiment, conveyance 200 is an electric line and operating assembly 202 is an electrical hydraulic pump. In this embodiment, the electricity provides the energy to operate the hydraulic pump such that fluid is pumped into piston section 198 , thereby placing an axially tensile force on expandable production packer 180 between latch profiles 194 , 196 which elongates this section of tubing 184 , as described herein, allowing for the release of expandable production packer 180 .
[0071] In yet another embodiment, conveyance 200 is an electric line and operating assembly 202 is a downhole power unit. In this embodiment, the electricity provides the energy to operate the downhole power unit to rotate a shaft that drives piston section 198 , thereby placing an axially tensile force on expandable production packer 180 between latch profiles 194 , 196 which elongates this section of tubing 184 , as described herein, allowing for the release of expandable production packer 180 .
[0072] In a further embodiment, conveyance 200 is an electric line and operating assembly 202 includes both a downhole power unit and a hydraulic pump. In this embodiment, the downhole power unit may be used to stroke the hydraulic pump such that fluid is pumped into piston section 198 , thereby placing an axially tensile force on expandable production packer 180 between latch profiles 194 , 196 which elongates this section of tubing 184 , as described herein, allowing for the release of expandable production packer 180 .
[0073] In all of these embodiments, once sufficient tensile force is generated and the diameter of tubing 184 between latch profiles 194 , 196 is reduced, the intimate contact between seal elements 182 A- 182 E and the interior of casing string 186 is released, such that tubing string 184 along with expandable production packer 180 can be retrieved to the surface.
[0074] Referring now to FIG. 16, therein is depicted another method of releasing an expandable production packer that is designated 210 . Expandable production packer 210 includes a plurality of seal elements 212 A- 212 E that are positioned around an expandable section of tubing string 214 that has previously been expanded using a technique described herein or other suitable technique. As illustrated, seal elements 212 A- 212 E are in intimate contact with the interior wall of casing 216 such that a sealing and gripping arrangement exists between production tubing 214 and casing 216 .
[0075] If it becomes necessary to retrieve expandable production packer 210 , the intimate contact of seal elements 212 A- 212 E with the interior of casing string 216 must be released. This is achieved using release member 218 . In the illustrated embodiment, release member 218 includes a pair of latching keys 220 , 222 that respectively match and lock into latch profiles 224 , 226 of tubing string 214 . Release member 218 also includes seal elements 228 , 230 that respectively create a fluid seal against seal bores 232 , 234 . Release member 218 further includes a piston section 236 and a receiver portion 238 that is coupled to the lower end of coiled tubing string 240 and that provides for fluid communication between coiled tubing string 240 and piston section 236 .
[0076] As described herein, once release member 218 and coiled tubing string 240 are positioned as depicted in FIG. 16, an axial force may be placed on expandable production packer 210 between latch profiles 224 , 226 by pumping a fluid into piston section 236 via coiled tubing string 240 . In this embodiment, not only does this tensile force cause elongation in the expandable section of tubing string 214 , elongation of seal elements 212 A- 212 E and a radially inward force based upon the difference in the diameter of tubing 214 between latch profiles 224 , 226 and the diameter of tubing 214 at latch profiles 224 , 226 , this tensile force also create a collapse force surrounding expandable production packer 210 .
[0077] Specifically, as expandable production packer 210 is elongated, the volume within expandable production packer 210 between seal elements 228 , 230 also expands. This expansion causes a drop in the pressure of the fluids trapped in this volume creating a differential pressure across the wall of expandable production packer 210 . This differential pressure creates a radially inwardly acting collapse force on expandable production packer 210 , which aids in the diameter reduction of tubing 214 between latch profiles 224 , 226 such that the intimate contact between seal elements 212 A- 212 E and the interior of casing string 216 is released. Thereafter, tubing string 214 along with expandable production packer 210 can be retrieved to the surface.
[0078] It should be understood by those skilled in the art that release member 218 as described herein could alternatively be used as an expander member to set an expandable production packer of the present invention. Specifically, by reconfiguring piston section 236 , fluid pressure delivered via coiled tubing string 240 could provide compression to the expandable section of tubing string 214 between latch profiles 224 , 226 . As this section of tubing 214 begins to shorten, the volume within expandable production packer 210 between seal elements 228 , 230 is reduced. This reduction causes an increase in the pressure of the fluids trapped in this volume creating a differential pressure across the wall of expandable production packer 210 . This differential pressure creates a radially outwardly acting expansion force on expandable production packer 210 , which aids in the diameter expansion of tubing 214 between latch profiles 224 , 226 such that intimate contact between seal elements 212 A- 212 E and the interior of casing string 216 can be created.
[0079] Referring now to FIG. 17, therein is depicted another method of releasing an expandable production packer that is designated 250 . Expandable production packer 250 includes a plurality of seal elements 252 A- 252 E that are positioned around an expandable section of tubing string 254 that has previously been expanded using a technique described herein or other suitable technique. As illustrated, seal elements 252 A- 252 E are in intimate contact with the interior wall of casing 256 such that a sealing and gripping arrangement exists between production tubing 254 and casing 256 .
[0080] If it becomes necessary to retrieve expandable production packer 250 , the intimate contact of seal elements 252 A- 252 E with the interior of casing string 256 must be released. This is achieved using release member 258 . In the illustrated embodiment, release member 258 includes a pair of seal elements 260 , 262 that respectively create a fluid seal against seal bores 264 , 266 . Release member 258 further includes a mandrel section 268 having a plurality of ports 270 and a receiver portion 272 that is coupled to the lower end of coiled tubing string 274 and that provides for fluid communication between coiled tubing string 274 and mandrel section 268 .
[0081] Once release member 258 and coiled tubing string 274 are positioned as depicted in FIG. 17, a collapse force may be created surrounding expandable production packer 250 by depressurizing the volume within expandable production packer 250 . Specifically, once fluid communication is established between this volume and the interior of coiled tubing string 274 by, for example, operating a sleeve valve to open ports 270 , the pressure of the fluids within this volume may be reduced by, for example, having a relatively light fluid within coiled tubing string 274 , which creates a differential pressure across the wall of expandable production packer 250 . This differential pressure creates a radially inwardly acting collapse force on expandable production packer 250 , such that the intimate contact between seal elements 252 A- 252 E and the interior of casing string 256 is released. Thereafter, tubing string 254 along with expandable production packer 250 can be retrieved to the surface.
[0082] Referring now to FIGS. 18 - 19 , therein are depicted another method of releasing an expandable production packer that is designated 280 . Expandable production packer 280 includes a plurality of seal elements 282 A- 282 E that are positioned around an expandable section of tubing string 284 that has previously been expanded using a technique described herein or other suitable technique. As illustrated, seal elements 282 A- 282 E are in intimate contact with the interior wall of casing 286 such that a sealing and gripping arrangement exists between production tubing 284 and casing 286 .
[0083] If it becomes necessary to retrieve expandable production packer 280 , the intimate contact of seal elements 282 A- 282 E with the interior of casing string 286 must be released. This is achieved by weakening the sections of tubing 284 behind seal elements 282 A- 282 E using a radial cutting tool 288 . In the illustrated embodiment, radial cutting tool 288 may be run downhole on an electric line 290 until a latching key 292 of radial cutting tool 288 locks into latch profile 294 . Radial cutting tool 288 may use any one of several cutting techniques that are well known in the art including, but not limited to, chemical cutting, thermal cutting, mechanical cutting, explosive cutting or the like.
[0084] For example, radial cutting tool 288 may be a chemical cutter such as that described in U.S. Pat. No. 5,575,331, which is hereby incorporated by reference. Once in place, radial cutting tool 288 is operated to cut a series of notches or grooves into the interior wall of expandable production packer 280 behind seal elements 282 A- 282 E. In the case of using the chemical cutter, a dispersed jet of cutting fluid is released through cutting ports 296 . In the illustrated embodiment, cutting ports 296 are circumferentially positioned at 90 degree intervals around radial cutting tool 288 such that the portion of tubing 284 behind seal elements 282 A- 282 E will have a series of axially oriented grooves or notches that are circumferentially positioned at 90 degree intervals relative to one another. It should be noted by those skilled in the art, however, that other cutting configurations may alternatively be used without departing from the principles of the present invention.
[0085] The chemical cutter is fired by an electrical signal carried via electric line 290 . The depth of cut made by the chemical cutter is predetermined and is controlled by the composition of chemicals loaded into the chemical cutter and the geometry of cutting ports 296 . Preferably, the chemical cutter is set to make a cut that partially penetrates the wall of expandable production packer 280 behind seal elements 282 A- 282 E.
[0086] Once the grooves or notches have been cut into expandable production packer 280 behind seal elements 282 A- 282 E by radially cutting tool 288 , radial cutting tool 288 may be retrieved to the surface. Thereafter, as best seen in FIG. 19, a plug 298 may be set below expandable production packer 280 and a sealing member 300 coupled to the lower end of a coiled tubing string 302 may be set above expandable production packer 280 . A collapse force may then be created surrounding expandable production packer 280 by depressurizing the volume within expandable production packer 280 . Specifically, once fluid communication is established between this volume and the interior of coiled tubing string 302 by, for example, operating a valve within seal member 300 , the pressure of the fluids within this volume may be reduced by, for example, having a relatively light fluid within coiled tubing string 302 , which creates a differential pressure across the wall of expandable production packer 280 . This differential pressure creates a radially inwardly acting collapse force on expandable production packer 280 . As the sections of tubing 284 behind seal elements 282 A- 282 E have been weakened as described herein, the collapse force acts preferentially on these sections, such that the intimate contact between seal elements 282 A- 282 E and the interior of casing string 286 is released. Thereafter, tubing string 284 along with expandable production packer 280 can be retrieved to the surface.
[0087] Even though FIGS. 18 - 19 have been described with reference to weakening the sections of tubing 284 behind seal elements 282 A- 282 E using a radial cutting tool 288 to create notches or grooves in tubing 284 , it should be understood by those skilled in the art the such a radial cutting tool could alternatively be used to completely cut through the sections of tubing 284 behind seal elements 282 A- 282 E. In this case, the collapse force that is created surrounding expandable production packer 280 by depressurizing the volume within expandable production packer 280 may be reduced or that step may be eliminated while still allowing release of seal elements 282 A- 282 E from the interior of casing string 286 .
[0088] While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is, therefore, intended that the appended claims encompass any such modifications or embodiments. | A well completion system for creating a seal between a production tubing ( 30 ) and a well casing ( 34 ) positioned within a wellbore ( 32 ) comprises a production packer ( 46 ) that includes a section of the production tubing ( 30 ) and at least one seal element ( 60 ). The production tubing ( 30 ) is then positioned within the well casing ( 34 ) that lines the wellbore ( 32 ). An expander member ( 56 ) that is positioned within the production tubing ( 30 ) then travels longitudinally through the production packer ( 46 ) to expand the section of the production tubing ( 30 ) downhole that includes the seal element ( 60 ). This expansion creates a sealing and gripping relationship between the production tubing ( 30 ) and the well casing ( 34 ). | 4 |
This application claims priority from U.S. Provisional Patent Application Ser. No. 60/299,556, filed Jun. 20, 2001.
FIELD OF THE INVENTION
The present invention is directed to the field of organic chemistry in general and specifically to the preparation of hydrophobic derivatives of cyclic ADP ribose.
BACKGROUND OF THE INVENTION
Intracellular calcium plays key roles in stimulation-secretion coupling in pancreatic islet β-cells. The elevation of cellular cytosolic calcium concentration ([Ca 2+ ] c ) is mediated through two pathways: Ca 2+ release from intracellular calcium stores and Ca 2+ influx from extracellular medium. The mechanisms underlying internal calcium release in β-cells remain incompletely understood, and the relative contribution of intracellular Ca 2+ release to the overall [Ca 2+ ] c increase and subsequent insulin secretion needs to be determined.
Ca 2+ release from intracellular stores is an important signaling mechanism for a variety of cellular processes and is generally controlled by two systems, the IP 3 and cADPR systems (FIG. 1 ). IP 3 acts directly on the IP 3 receptor (IP3R) localized in the endoplasmic reticulum (ER). IP3R forms the Ca 2+ releasing channel and regulates the efflux of Ca 2+ from the ER to the cytosol. Cyclic ADP ribose increases the opening probability of other intracellular Ca 2+ releasing channel formed by the ryanodine receptor (RyR) in the ER.
Ca 2+ influx through voltage gated Ca 2+ channels is a well-characterized phenomenon in β-cells, and it is thought to play an important role in maintaining Ca 2+ homeostasis, especially during glucose stimulation. However, contributions from internal calcium release cannot be ignored. Ca 2+ influx from extracellular sources and Ca 2+ release from the intracellular pool in human β-cells has been examined, and showed that 42-75% of the increase in intracellular Ca 2+ by glucose stimulation was due to the release of Ca 2+ from the intracellular stores. Both IP 3 and cADPR signaling systems have been reported in insulin secreting β-cells, but controversies remain regarding which system is more important for maintaining proper insulin secretion responses.
To examine IP 3 or cADPR induced Ca 2+ release in β-cells, it is necessary to deliver these second messengers inside cells and assay their effects on cellular calcium homeostasis and insulin secretion. Methods relying on triggering cell surface receptors to produce endogenous IP 3 or cADPR inevitably activating other signaling pathways, making it impossible to separate the effects caused by IP 3 or cADPR from those caused by other signaling branches. To deliver exogenous IP 3 or cADPR inside cells, one need to overcome the difficulty of getting them across cell membranes. Both IP 3 and cADPR are charged and hydrophilic molecules at physiological pH, thus are membrane impermeant. Previous techniques of getting these two molecules across hydrophobic cell membranes include microinjection, patch clamping, electroporation or detergent assisted permeabilization. All these methods are invasive and suffer from major drawbacks such as disrupting intact cell membranes, letting cytosolic factors leak out of cells, and compromising long term viability of cells. In addition, techniques such as microinjection or patch clamping can only be applied to single cells, making it practically impossible to study more physiological preparations such as islets.
SUMMARY OF THE INVENTION
One form of the present invention is a hydrophobic compound of the general formula:
where R 1 , R 2 , R 3 and R 4 are each independently hydrogen or linear or branched alkyl groups having from 1 to 12 carbon atoms. R 5 and R 6 are each an alkyl group, metallic cation, a photo-labile caging group, or an acyloxymethylgroup or a homologue thereof. W is CH 2 , CF 2 , or CHF. X is N or CH. Y is N or CH. Z is chosen from the group including H, Br, NH 2 , OCH 3 , CH 3 and N 3 .
Another form of the invention is a method for preparing a hydrophobic composition comprising the following steps:
where RO and R′O comprise independently in each location carboxylate groups further comprising from 2 to 20 carbon atoms.
BRIEF DESCRIPTION OF THE FIGURE
The above and further advantages of the invention may be better understood by referring to the following detailed description in conjunction with the accompanying drawings in which corresponding numerals in the different FIGURES refer to the corresponding parts in which:
FIG. 1 depicts aspects of calcium metabolism in accordance with the present invention;
FIG. 2 depicts a pathway in accordance with the present invention;
FIG. 3 depicts an 8-amino cADPR (left) and a hydrophobic derivative of cyclic ADP ribose (right) in accordance with the present invention;
FIG. 4 depicts a pathway of the cellular delivery of phosphate- or phosphanate-containing compounds in accordance with the present invention;
FIG. 5 depicts methanodiphosphonate alanogues of pyrophosphates and neutral esters in accordance with the present invention;
FIG. 6 depicts a synthetic scheme for preparing a photocaged and hydrophobic derivative of cyclic ADP ribose in accordance with the present invention;
FIG. 7 depicts another synthetic scheme for preparing hydrophobic derivative of cyclic ADP ribose in accordance with the present invention; and
FIG. 8 depicts the synthesis of an ester of a methane-diphosphonate derivative of cyclic ADP ribose.
DETAILED DESCRIPTION OF THE INVENTION
While the making and using of various embodiments of the present invention are discussed herein in terms of organic chemistry, it should be appreciated that the present invention provides many inventive concepts that may be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of ways to make and use the invention are not meant to limit the scope of the present invention in any way.
Terms used herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as “a,” “an,” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not limit the invention, except as outlined in the claims.
Novel techniques to prepare hydrophobic derivatives of phosphate-containing molecules including cADPR have been developed. These hydrophobic derivatives are expected to diffuse across cell membranes of fully intact cells and regenerate their parent molecules by cellular esterase hydrolysis. Photo-chemical uncaging techniques may also be used to activate these molecules with desired temporal and spatial precision. A “caged” molecule is masked by a photo-labile protecting group, and is thus biologically inactive. Photolysis with a flash of UV light (“uncaging”) removes the photo-labile protecting group to restore the biological activity of the molecule abruptly. Caged and hydrophobic derivatives of cADPR serve as powerful pharmacological tools for the to study of their roles in cellular Ca 2+ signaling, and allow the assay of their effects on insulin secretion in intact cell populations.
A natural metabolite, cADPR, has been purified from sea urchin egg homogenates and was found to have Ca 2+ -mobilizing activities. Cyclic ADP ribose showed distinct Ca 2+ releasing properties from ones caused by IP 3 . Pharmacological studies suggested that cADPR mediates Ca 2+ release through ryanadine receptor (RyR), one of the two major intracellular Ca 2+ releasing channels (the other is IP3R). Cyclic ADP ribose has been shown to be able to release Ca 2+ from intracellular stores in a number of mammalian cells.
Cyclic ADP ribose is formed in one step from NAD + , a common reduction-oxidation cofactor. The reaction is catalyzed by an enzyme, ADP ribosyl cyclase, that was first purified, sequenced, and cloned from the ovotestis of the marine mollusk Aplysia. The enzyme activity was also found to be present in many, if not most, mammalian tissues. Considerable homology (69%) of the amino acid sequence between Aplysia ADP-ribosyl cyclase and human lymphocyte surface antigen CD38 has been observed. Subsequent studies from a number of laboratories showed that CD38 from human, mouse, and rat possess ADP-ribosyl cyclase activity, synthesizing cADPR from NAD + . CD38 has also been found to exist in many animal tissues, and in both plasma membrane and microsomal membrane fractions.
There have been a number of discrepancies regarding the signaling role of cyclic ADP ribose. The mechanism of how cADPR activates ryanadine receptors is not fully understood at the moment, but it appears that cADPR requires the presence of other proteins such as calmodulin to exhibit its biological activity. The lack of Ca 2+ responses to cADPR using permeabilized cells, microinjection or patch clamping technique may be due to diluting cytosolic factors required for the action of cADPR. Moreover, since the extracellular calcium concentration is more than 10 5 fold higher than [Ca 2+ ] c , it is difficult to keep cellular calcium under low levels during these invasive manipulations. In contrast, hydrophobic derivatives of cADPR or IP 3 can be applied to fully intact cells, thus allowing us to test their effects on Ca 2+ release, glucose stimulated insulin secretion (GSIS), and other downstream biochemical events reliably.
Prodrug Design and Intracellular Delivery of Phosphate-containing Molecules.
Because phosphates are ionized and hydrophilic species at physiological pH, phosphate-containing molecules usually do not cross hydrophobic lipid membranes. The concept of prodrug design from pharmaceutical industry has been used to design hydrophobic derivatives of IP 3 and other inositol polyphosphates. Prodrug design comprises an area of drug research that is concerned with the optimization of drug delivery. A prodrug is a pharmacologically inactive derivative of a drug that requires spontaneous or enzymatic transformation within the body in order to regenerate its active parent drug molecule.
Analogues of Cyclic ADP Ribose and Their Hydrophobic Derivatives
To deliver cADPR inside cells, the negative charges on the pyrophosphate must be covered. However, neutral esters of pyrophosphates are highly unstable in aqueous solutions, spontaneously breaking down into two phosphates (FIG. 5 ). Replacing the center oxygen atom with a methylene group forms a methanediphosphonate. The neutral esters of methanediphosphonate are stable because the center P-C bond is not susceptible to hydrolysis.
The synthetic scheme of compound 1 (as shown in FIG. 2) is outlined in FIG. 6 . Briefly, the starting material dibutyryl adenosine is coupled with the methanediphosphonate methyl ester. The resulting intermediate is coupled to another ribose derivative. Formation of the macrocycle is catalyzed TMS triflate using Hilbert-Johnson reaction to form the N1-glycosidic bond (step b in FIG. 6 ). After removing methyl groups with lithium cyanide (step c), the resulting methanediphosphonate is sequentially protected with one equivalent of NPE group (step d) and PM group (step e) to generate the target molecule 1. An alternative synthetic pathway for another hydrophobic derivative is shown in FIG. 7 .
Example of Synthesis of an Ester of a Methane-diphosphonate Derivative of Cyclic ADP Ribose
The synthesis of a methane-diphosphanate derivative of cyclic ADP ribose is shown in FIG. 8 . Initially, 2′, 3′-dibutyryl-5′-O-tosyl adenosine (Compound 9) is prepared from adenosine in 4 steps following general procedures apparent to those of ordinary skill in the art. The structure was analyzed by 1 H NMR (i.e., CDCl 3 ; chemical shifts in ppm) and showed results of 0.95 (6H, m, CH 3 ), 1.6 (4H, m, CH 2 ), 2.25 (4H, m, CH 2 ), 2.4 (3H, s, CH 3 ), 4.39 (3H, m, H4′ & H5′), 5.56-6.14 (3H, H3′, H2′ & H1′), 7.26 (2H, d, ArH, J=8.4 Hz), 7.75 (2H, d, ArH, J=8.4 Hz), 7.93 (1H, s, H2), 8.28 (1H, s, H8).
The synthetic intermediate 1,2,3-tri-O-acetyl-5-O-tosyl ribofuranose is prepared from D-ribose using the literature procedure. 1 H NMR results (CDCl 3 ; in ppm) are as follows: 2.04-2.11 (9H, m, COCH 3 ), 2.45 (3H, s, Ar—CH 3 ), 4.05-4.2 (3H, m, H4, H5), 5.02-5.4 (1H, m, H3), 5.31 (1H, m, H2), 6.09 (s, H1β) & 6.25 (d, J=7Hz, H1α, 1H combined), 7.36 (2H, t, ArH, J=6.3 Hz), 7.79 (2H, t, ArH, J=6.3 Hz).
The synthetic intermediate P1, P2-diethyl methanediphosphonate bis(tetra-n-butyl ammonium) salt is prepared according to a previously reported method from the corresponding tetraethyl ester. The 1 H NMR results (CDCl 3 , ppm) include: 0.84 (24H, t, CH 3 ), 1.05 (6H, m, CH 2 ), 1.31 (16H, m, CH 2 ), 1.52 (16H, m, CH 2 ), 1.91 (2H, m, P—CH 2 —P), 3.25 (16H, m, CH 2 ), 3.87 (4H, m, CH 2 ); 31 P NMR results (CDCl 3 ): 15.99 (s).
Compound 10 or P1-5-O-(1, 2, 3-triacetyl)ribosyl P2-5′-O-(2′,3′-dibutyryl)adenosyl P1,P2-diethyl methylenediphosphonate is prepared as discussed below (see FIG. 8 ). In brief, 2′, 3′-dibutyryl-5′-O-tosyl adenosine (at least about 0.925 g, 1.65 mmol) and P1, P2-diethyl methanediphosphonate bis(tetra-n-butyl ammonium) salt (at least about 1.135 g, 1.59 mmol) are heated in DMF (1 mL) for 18 hours at 80-90 degrees Centigrade under argon. Next, 1,2,3-tri-O-acetyl-5-O-tosyl ribofuranose (0.817g, 1.9 mmol) was added to the reaction mixture and the mixture was heated for another 20 hours. After removing the solvent under vacuum, the residue was purified on a silica gel column (e.g., CH 2 Cl 2 /MeOH) to yield the unsymmetrical tetraester Compound 10 (the yield may be at least around 0.323 g or a 22% yield). Results of 1 H NMR(CDCl 3 , ppm) show the following: 0.8-09(6H, CH 3 ), 1.32 (6H, m, CH 3 ), 1.56 (4H, CH 2 ), 2.00 (9H, m, COCH 3 ), 2.22 (4H, COCH 2 ), 2.5 (2H, m, P—CH 2 —P), 4.1 (4H, m, OCH 2 ), 4.38 (6H, m), 5.35 (3H, m), 5.6-5.9 (3H, m), 6.1 (1H, s), 6.2 (1H,d), 6.62 (2H, m), 8.45 (2H, m, H2 & H8); 31 P NMR (CDCl 3 , ppm) 20.4-21.8 (m). Mass spectroscopy analysis was performed, where the mass (Electrospray, positive) that was calculated for C 34 H 51 N 5 O 18 P 2 was 880.27 ([M+H] + ) and found to be 880.56.
The neutral ester of a methane-diphosphonate derivative of cyclic ADP ribose or Compound 11 is prepared as follows (see FIG. 8 ). First, BSTFA (6 equivalents) was added to a solution of the Compound 10 (at least about 20 mg or 2.27×10 −5 mol) in 5 mL CH 3 CN. TMSOTf (2 equivalents) was added subsequently and the mixture was stirred at room temperature for 6 hours. Another two equivalents of TMSOTf were then added. The reaction was quenched about two hours later by 1 mL saturated NaHCO 3 and extracted with dichloromethane. The organic layer was dried and purified on a silica gel column (e.g., CH 2 Cl 2 /MeOH) to give Compound 11 as analyzed by mass spectroscopy where the Electrospray, positive calculation for C 32 H 47 N 5 O 16 P 2 was 820.25 ([M+H] + ) and found to be 820.22.
Although this invention has been described in reference to illustrative embodiments, the description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. It is therefore intended that the appended claims encompass any such modifications or embodiments. | The present invention is directed to the field of organic chemistry in general and specifically to the preparation of hydrophobic derivatives of cyclic ADP ribose. One form of the present invention is the composition of one or more hydrophobic derivatives of cyclic ADP ribose. In another form of the present invention, a method for preparing a hydrophobic composition is described. Compositions of the present invention are useful for the study of in vivo calcium metabolism. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to the field of dentistry and more particularly relates to dental prosthetics.
BACKGROUND OF THE INVENTION
[0002] The standard procedure for creating porcelain restorations among the majority of dentists today consists of:
1. taking an accurate impression with polyvinyl siloxane elastomeric impression material; 2. creating a casting of the impression with dental stone (gypsum); and 3. sending the related castings out to an independent lab that creates the porcelain prosthetics.
[0006] This process usually takes days to weeks before a final prosthetic can be cemented into the patient's mouth. The patient in the interim must be fitted with a temporary appliance cemented in with temporary cement. A second appointment is made and upon return the temporary crown is removed and the cement is arduously cleaned off the tooth, at which point the final prosthetic can be cemented and fitted into place. Without an alternative procedure to replace this standard practice, the current procedure creates many problems:
1. Scheduling conflicts—The dentist must coordinate the return of the prosthetic from the lab and the patients' busy schedule. 2. The dentist is totally reliant on an independent lab for a successful outcome. 3. The days to weeks delay and the often poor fitting temporary appliances allows the teeth to move during the interim period, therefore the dentist usually has to adjust the prosthetic before fit and bite are adjusted properly. 4. Complete removal of residual temporary cement is near impossible resulting in sometimes-lower adhesive strengths with the final cementation.
[0011] Recent advances in dentistry allow dentists to make porcelain restorations without sending an impression to a lab. Recent advances in CAD/CAM and mini-CNC technology have begun to make an impact on the customary process for creating prosthetics. These new advances obsolete many of the frustrations created by the old process. The entire prosthetic manufacturing can be done in the dental office and on the same day. The process usually consists of:
1. taking a 3D image of the treatment area with a sophisticated camera and software system either intra-oral or on a plaster (or other similar material) mold previously taken according to the methods described above; 2. using CAD software to design the desire prosthesis; 3. downloading the resulting file to a small milling machine in which is loaded a pre-cast block of consumable porcelain; 4. using the mill to carve the appropriate prosthetic; and 5. cementing the resulting final prosthetic into the patient on the same day.
[0017] This newer process obsoletes impression materials, dental stone, second appointments, temporary prosthetics, temporary cements and independent labs all present in the first, older, method described above. Obviously these advantages have dentists moving toward these new technologies. This has opened up a new market for the consumable components that service these milling machines. Many companies today make porcelain blocks of various compositions that fit into these milling machines. It should be understood that “porcelain” is a ceramic including oxides of aluminum, silicon, and mineral combinations of these elements.
[0018] A variety of prosthetic materials are vying for supremacy, the industry and dentist both desiring the optimum characteristics of the prosthetic. The longevity and endurance of the prosthetic installed in the patient being a paramount factor for the dentist. A cracked, de-laminated, broken or chipped prosthetic results in a phone call from an annoyed patient and a replacement prosthetic usually at the dentists cost. Therefore the need for improved prosthetic materials is essential to the success of a modern dental office.
[0019] The ceramic materials also include a variety of minerals including lead and mercury, which cause sensitivity and toxicity for different patients.
[0020] This patent has to do with improved materials and methods of manufacturing of dental prosthetics. The majority of the materials used in current practice usually consist of:
1. Porcelain fused to metal prosthetics. 2. All porcelain prosthetics. 3. Porcelain laminated to Alumina prosthetics. 4. Porcelain laminated to Zirconia Prosthetics.
[0025] Independent labs are usually capable of producing all of the above listed prosthetics with the all porcelain prosthetics being the only choice for in-office milling machines. These materials offer various advantages and disadvantages. The ideal characteristics warranted in these materials usually consist of:
1. Strength and toughness—a resistance to tensile, compressive and shear forces. 2. Fracture toughness—a resistance to cracks and crack propagation and chips that eventually results in overall failure 3. Lamination integrity—A resistance to de-lamination of 2 or more materials bonded together. 4. Wear resistance—A resistance to friction wear due to daily and expected use of the material. 5. Toxicity—minerals in the ceramics may result in sensitivity and toxicity for patients.
[0031] The above factors are the predominate issues that weigh the most heavily in current materials of choice. There are other minor characteristics to examine in these materials, but do not become an issue since the dominant issues have yet to be solved. These issues plague the current array of materials used today. A recent study of prosthetic materials have shown defects such as chips, cracks, de-laminations and complete failures in these prosthetics as high as 70% after 2 years. The materials of choice today have leaned toward inorganic ceramics/porcelains. Ceramics are very hard and strong. The hardness of these materials means they are also brittle. Unfortunately, being ceramic, ceramic prosthetics behave similar to glass. A single chip or micro-fracture will eventually lead to complete failure. This is similar to a small chip in a glass windshield that eventually results in a large crack. Ceramics/Porcelains have good strength, toughness, and wear resistance; but have poor fracture resistance. Once ceramics/porcelains acquire a defect, even if the defect is very small they will eventually crack and fail. Milling ceramics, like porcelain, is also very expensive and difficult, requiring expensive tooling and causing extreme wear on those tools. There is also the inherent risk of fracture during the milling process. Due to the difficulties inherent in milling ceramics, there is no capability of milling anything but a single tooth. Multi-tooth, monolithic appliances are all but impossible to create. What are needed are prosthetics made from non-laminated materials with good strength, toughness, wear resistance and especially fracture resistance. The prosthetics also need to be made from a material that will not fail due to a small defect and will resist fracture propagation.
[0032] The technology of the present invention comprises novel materials and an expedited means of manufacture. These new materials depart from the prior art in that they incorporate organic materials; more specifically they encompass organic polymers. These polymers selected from the group that best impart the essential characteristics warranted for dental prosthetics. Furthermore, the ideal polymer should be capable of being moldable; more specifically they encompass materials that are capable of being injection moldable.
[0033] The present invention represents a departure from the prior art in that the prosthetics of the present invention utilize organic plastics which are durable and permanent, while also being fashioned in the dentist's office for same day installation in a patient.
SUMMARY OF THE INVENTION
[0034] In view of the foregoing disadvantages inherent in the known types of dental prosthetics, this invention provides rapid generation of customizable plastic dental prosthetics. As such, the present invention's general purpose is to provide a new and improved dental prosthetics that are inexpensive and simple to manufacture in a dental office while also providing the durability and extended life span of a truly permanent dental prosthetic.
[0035] The present invention incorporates the use of high strength plastics that are capable of being easily and quickly molded by machines. The industry of molding plastics/polymers into a pre-designed shape is well known. The process produces large quantities of reproducible parts at economical prices. The latest advances in polymer chemistry have resulted in plastics with high strength, wear resistance and fracture resistance. These new plastics cannot only be made into dental prosthetic, but also, with new small-scale manufacturing techniques, be made on site in a dental office for immediate use in a patient.
[0036] The more important features of the invention have thus been outlined in order that the more detailed description that follows may be better understood and in order that the present contribution to the art may better be appreciated. Additional features of the invention will be described hereinafter and will form the subject matter of the claims that follow.
[0037] Many objects of this invention will appear from the following description and appended claims, reference being made to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.
[0038] Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
[0039] As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0040] Plastics have an ability to be strong and deform without fracturing under stress. This inherent ability of some polymers to deform (flex/stretch) instead of fracturing is ideal for a prosthetic dental material. Even plastics that are brittle can be modified by plasticizers to impart more elasticity to the polymer in order to make them useful as an ideal prosthetic material. Usable plastics can be a thermoplastic or a thermoset plastic. These polymers can be comprised of straight chain, co-polymeric, block or any combination of polymers incorporated into the same mass. Plastics can be chosen from the group of polymers such as: polyacrylates, polyamide-imide, phenolic, nylon, nitrile resins, fluoropolymers, copolyvidones (copovidones), epoxy, melamine-formaldehyde, diallyl phthalate, acetal, coumarone-indene, acrylics, acrylonitrile-butadiene-styrene, alkyds, cellulosics, polybutylene, polycarbonate, polycaprolactones, polyethylene, polyimides, polyphenylene oxide, polypropylene, polystyrene, polyurethanes, polyvinyl acetates, polyvinyl chloride, poly(vinyl alcohol-co ethylene), styrene acrylonitrile, sulfone polymers, saturated or unsaturated polyesters, urea-formaldehyde, or any like or useful plastics. Currently, the preferred plastics of the present invention include: Poly ether ether ketone (PEEK), Hi-lubricity nylons, impact resistant polymethylmethacrylate and fluoro-polymers. These polymers are high strength plastics that are resistant to wear and fracturing. They are also resistant to moisture and chemicals. The preferred plastic would also be selected from the group of thermoplastics that are capable of being injection molded, such that the entire polymer block and insert that loads into the dental milling machine can be injection molded completely. It is also possible for the block to be made of a polymer and injection molded onto a metal insert; the metal insert being loaded into the milling machine in order to hold the polymer block for milling.
[0041] Various polymers can also be modified in order to maximize the warranted characteristics for a dental prosthetic. This usually means incorporating the addition of a plasticizer or filler into the plastic. Plasticizers usually impart more elasticity to the polymer, therefore rendering them more resilient. A few examples of possible plasticizers include: mineral oil, triethyl citrate, acetyltriethyl citrate, lauric acid, modified vegetable oils, diacetylated monoglycerides, castor oil, sucrose diacetate hexaisobutyrate, triacetin, glycerin, liquid polyethylene glycols, liquid poly propylene glycols, propylene glycol, dimethyl phthalate, diethyl phthalate, dipropyl phthlate, dibutyl phthalate, dioctyl phthalate, polysorbates or any like or useful plasticizer.
[0042] Fillers can also be incorporated into the plastic. Fillers usually modify the wear resistance, elasticity, fracture toughness and strength of the plastic. A filler can be comprised of either powder or fiber, such as pieces of monofilament. A few examples of possible fillers would be silica, silica carbide, plastic monofilaments, carbon fiber, zirconia, alumina, borosilicate glass powder, radiopaque borosilicate powder, other radiopaque substances, titanium dioxide, zinc oxide, pigments, or any like or useful filler.
[0043] The plastic, filler and plasticizer can be adjusted to impart essential characteristics to polymers that may be otherwise questionable as a useful dental prosthetic material. Pigments may also be added in order to manufacture all the shades needed to match the teeth of the human race.
[0044] The polymers used in the present invention are loaded and melted in an injection-molding machine that reproduces a block that fits into the dental milling machine. The mold may incorporate inserts and base prosthetics into itself. Since the block is molded for the milling machine, only one mold, or a series of standard interchangeable molds for size, are necessary, keeping costs lower. The mold is then subsequently cooled and the solidified block is released from the mold. Blocks are then sold to dentists in various shades and sizes. As used in this specification, the term “block” may be any shape, including cubes, spheres or round and polyhedral cylinders, and may or may not include a protruding end to fit in some milling machines. The protruding end may be of the same material as the block or may be an inserted post made of metal or some other material. The dentist then selects and inserts the finished polymer block into the milling machine and the polymer block is milled into a prosthetic, similar to the milling of porcelain prosthetics. The milled prosthetic is then fitted and cemented permanently into place on the same day as the initial visit. Polymer prosthetics such as a crown, bridge, inlay, or onlay can be milled from these polymer blocks. The technology of the present invention is compatible with rapid prototyping equipment that would be near impossible for the technology of the prior art. Ceramics and porcelain melt at over 1000 C and are therefore confined for use in a furnace. The plastics of the present invention melts at much lower temperatures such that they could be used in commercial rapid prototyping machines. There are various types and methods of rapid prototyping technologies available that could be customized to build the prosthetics of the present invention. Examples of Rapid Prototyping technologies include but are not limited to: Selective Laser Sintering (SLS), Fused Deposition Modeling (FDM), Laminated Object Manufacturing (LOM), 3D Printing (3DP), Stereolithography (SLA), Electron Beam Melting (EBM), and any like method or device. An example of integrating the technology of the present invention with a rapid prototype device utilizing the Fused Deposition Modeling (FDM) technology is forthwith given, it is to be understood that this description is exemplary and each method, including future prototyping methods, may be used in the present invention. Fused Deposition Modeling is an additive process that successively builds an engineered construct that is pre-designed through modeling software such as computer aided design programs (CAD). One such device uses a polymer to create the body of the construct, said polymer delivered as a plastic feed wire. The plastic feed wire is directed to a heated nozzle that melts the plastic and controls the delivery of the molten plastic during the additive build-up process. Following the design being downloaded from the CAD software, the nozzle or the platform will usually move with respect to an X, Y and Z axis of the Cartesian coordinates; the construct being built between the platform and the nozzle. The heated plastic ultimately flows out the nozzle onto the platform at precise times and coordinates in a single layer or strand that quickly cools. This solid layer is then successively built upon with additional strands or layers into a designed construct. By this method crowns, inlays, onlays, dentures and bridges can be constructed. Plastics of the present invention could therefore be incorporated into (FDM) technology to build prosthetics for dental, medical or veterinary use. Rapid prototype technology coupled with imaging scanners offer an even greater advantage over the prior art. Image scanners would be utilized to capture a 3D image of the treatment area and, through the use of additional modeling software, create a custom image of the desired prosthetic for download, a model that would more precisely fit the treatment area. Commercially available milling machines are only capable of milling small prosthetics such as a crowns, inlays or onlays. The technology of the present invention coupled with rapid prototype devices and image scanners would allow larger prosthetics such as custom bridges, bones and dentures that are not manufacturable by prior art milling machines. The general process for the preferred method usually comprising:
1. A 3D scanner scans the anatomical surfaces of the area to be treated. 2. Said image is then manipulated into a desired prosthetic model by modeling software 3. The final image model downloaded to the rapid prototype device wherein the plastic of the present invention is incorporated. 4. The rapid prototyping device is then activated and successively constructs the prosthetic by the additive process. 5. The finished prosthetic is then polished and cemented into place; optionally correcting any abnormal anatomy if necessary.
[0050] From this example other rapid prototyping devices, machines, procedures and methods could be utilized to build prosthetics of the present invention for physiological use; whether they utilize: additive, curing, vaporization, subtractive, and/or any other rapid prototyping method.
[0051] It is also possible to a produce an entire denture appliance by this method. The present technology also provides means for improved prosthetics and appliances that result in less failure; this in turn results in less return visits by the patients.
[0052] Although the present invention has been described with reference to preferred embodiments, numerous modifications and variations can be made and still the result will come within the scope of the invention. No limitation with respect to the specific embodiments disclosed herein is intended or should be inferred. | The present invention is dental prosthetics manufactured from polymers rather than ceramics. Various plastics are disclosed for use in making said prosthetics, as are techniques for improving plastic performance in the prosthetics. The prosthetics are first injection molded into pre-set blocks for use in milling machines that dentists use or custom fit prosthetics with less wait time and less cost. Alternatively, an electronic model may be produced using image scanners. The electronic model may then be downloaded into rapid prototyping machine and a prosthetic therein built. Use of these methods may create various monolithic prosthetics, including multi-tooth prosthetics and whole bridges. | 1 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to a thin-layer laminate having utility as a getter for undesired gaseous contaminants in a vacuum enclosure, and to a vacuum enclosure characterized by the presence of this getter.
Without prejudice to the broad concept and scope of the invention, the background will be described with particular reference to high vacuum devices in the form of Infra-red (IR) radiation detectors. These commonly comprise a dewar envelope having an inner wall and an outer wall, a vacuum space being present between the inner and outer walls; the inner wall defines an inner chamber of the dewar; an infra-red radiation detector element is mounted in the vacuum space and on the end face of said inner wall; a cooling element is provided in the inner chamber and serves to cool the inner wall and the detector element mounted thereon during operation of the detector. The cooled inner wall is often termed “the cold finger” of the detector.
It is known that a prime cause of detector failure is the gradual degradation of the vacuum in the space between the inner and outer walls due to diffusion and internal out-gassing of the various parts of the detector. The excessive out-gassing which occurs in infrared detectors is associated with the fact that the gases cannot be driven out by baking the whole device during pumping (in the way which is usual for other vacuum devices) because infrared detector elements are damaged at high temperatures. Hydrogen is the most destructive gas for semiconductor devices (gallium arsenide and/or indium phosphide), most thermo-conductive gas and besides it is also the most difficult gas component to remove. It has been established that hydrogen is the primary cause of performance degradation in these devices in RF, AC, and DC operating modes.
This degradation in the vacuum eventually leads to the situation in which the cooling element is no longer able (at least in an efficient manner) to cool the detector element sufficiently fast to the desired temperature for efficient detection of infra-red radiation. Thus, the detector lifetime is curtailed, especially as only limited cooling power is available for infrared detectors. Furthermore, the out-gassing into the vacuum space provides a thermal path between the cold finger and the outside of the detector possibly leading to the formation of dew on the infrared window of the detector in a normal atmosphere.
In order to reduce the effects caused by this internal out-gassing at least one getter is normally provided in the vacuum space for removal of undesired gas molecules from this space.
Usually an infrared detector incorporates a non-evaporable chemically-active SAES getter (e.g. SAES Getters Inc., St 171-St 172 Brochure;) which is mounted on the outer wall and in the vacuum space between the outer wall and the cold finger. Such chemical getters are typically activated by heating to a high temperature after evacuation and sealing of the dewar envelope. This is normally achieved with an electrical heating element embedded in the getter material formed as a unit with electrical connection leads passing through vacuum-tight seals in the dewar wall (C. Taylor, S. Whicker, “Thermal Energy Receiver”, U.S. Pat. No. 3,851,173). Such getters, when mounted on the outer envelope, require minimal spacing from the detector elements which could otherwise be damaged by the very high activation temperature. In some cases extra heat shields are used to protect the internal components from being damaged during this getter activation process. Though this type of architecture is effective in removing the residual gas molecules from the volume, it often leads to an increased size for the dewar envelope and even adoption of unconventional dewar envelopes. In addition the high temperatures reached during getter activation are also the source for additional internal out-gassing as a result of the unavoidable heating of the internal components.
These limitations of current designs are constantly driving developments seeking alternative solutions in getter applications, that would allow for a more simplified construction and a reduced activation temperature inside the detector enclosure.
The getter is typically a reactive solid material that either adsorbs, absorbs, chemisorbs, or catalyzes a reaction that immobilizes or destroys one or more targeted contaminant compounds, in particular contaminant gases. For example, hydrogen can be released from various sources within an enclosure containing electronic assemblies and subassemblies. Hydrogen does not readily escape from environmentally sealed enclosures and reacts with hydrogen sensitive components. Furthermore, the unique thermal properties of hydrogen can be the cause of increased thermal loss. Several metals and nonmetals, used in production of IR detector components, can contain dissolved hydrogen that is released over time. The package materials can also sometimes release hydrogen. Plated nickel layers used as a barrier layer for gold plating operations and plastic resins are known to release hydrogen in amounts that can degrade the vacuum level and performance of semi-conductor and electrical components (R. Ramesham, “Getters for Reliable Hermetic Packages”, JPL Publication D-1792/NASA, pp 14-17, 1999).
As regards other undesired contaminants, e.g., glass (quartz elements of the device) often contains inside a certain quantity of water, and this component is gradually released as water vapor in the device volume. Organic compounds are often responsible for the presence of water vapor, carbon monoxide CO, and carbon dioxide CO 2 within the sealed device. Additional gas mixtures may be generated during device manufacturing procedures such as the out-gassing process, welding, and high-rate heating of the pumping tube, when it is disconnected from vacuum pump system.
U.S. Pat. No. 5,365,742 (Boffito, et al.) describes a device for the removal of hydrogen from a vacuum enclosure at cryogenic temperatures, which comprises a metal support (e.g. an Al strip) a composition able to absorb hydrogen, adherent to at least one surface of the support. The composition comprises a porous absorber of water vapor, preferably powdered alumina in contact with palladium oxide PdO which preferably covers, at least partially, the water absorber. In practice Pd(OH) 2 mixed with alumina may be precipitated on and attached to the support, then reduced to Pd metal, and re-oxidized to PdO.
U.S. Pat. No. 5,888,925 (Smith et al.) discloses a hydrogen absorbing material, and a method for its manufacture wherein platinum group metal oxide(s), a desiccant (such as a molecular sieve) and a matrix-forming binder (such as an RTV silicone) are mixed together; and the mixture is cured in an oxygen-containing gas (e.g. air) for a time (e.g. at least 24 hours) and a temperature (e.g. 150-204° C.), such that the material is stabilized from self-catalytic degradation.
DEFINITIONS
In the present specification and claims, the following definitions apply. “Active metal” means one or more of magnesium, strontium, calcium, barium, cadmium, iron, titanium, aluminum, hafnium and zirconium. “Platinum group metal” means one or more of ruthenium, rhodium, palladium, osmium, iridium and platinum. In the thin-layer laminate of the invention, reference to vacuum deposition of substances on a substrate and similar expressions, includes deposition either on one side of a substrate, and, where the context allows (such as in the case of a foil substrate) deposition either on one side on both sides of the substrate.
“Vacuum deposition” and similar expressions includes techniques such as sputtering; (including cathode DC sputtering, RF sputtering, reactive sputtering, etc.), evaporative metal deposition (including reactive evaporative deposition, thermal resistive evaporation, electron beam evaporation, etc.), ion plating, and neutralized ion beam coating.
The aluminum or titanium substrates (e.g. foil substrates) mentioned herein include alloys of aluminum and/or titanium known in the art.
OBJECTS OF THE INVENTION
It is an object of the invention to provide a gettering solution that allows for a more compact design of hermetically sealed vacuum devices than in conventional getter configurations.
It is a further object of the invention to provide a thin-layer laminate having utility as a getter for undesired gaseous contaminants in a vacuum enclosure.
Another object of the invention is to provide a getter unit having a large active specific surface area, and yet can be accommodated in the small space of a compact high vacuum device such as a detector envelope, in the latter case without requiring an increased envelope size or an unconventional envelope outline for its accommodation.
Still another object of this invention is to provide a gettering method that does not require adjunct heating devices or very high temperatures for initial activation.
Yet another object is to provide a combined solution which provides high absorption of stray IR radiation in addition to the function as getter for undesired gases.
Other objects of the invention will be apparent from the description which follows.
SUMMARY OF THE INVENTION
The present invention provides, in one aspect, a vacuum enclosure which is defined by a wall having inner and outer surfaces, where the inner surface is in contact with the vacuum and the outer surface is in contact with ambient air, and which is characterized by presence therein of a getter for undesired gaseous contaminants, wherein the getter comprises a substrate having deposited thereon a thin-layer vacuum deposited laminate including at least one layer of oxide(s) of at least one platinum group metal, and at least one porous hydrophilic layer. In one embodiment the substrate may be a discrete substrate which is not integral with an inner surface of the wall of the vacuum enclosure. In a different embodiment, the substrate is integral with an inner surface of the wall of the vacuum enclosure.
In the vacuum enclosure of the invention, the getter is also preferably characterized by at least one of the following features: (a) the at least one layer of oxide(s) of at least one platinum group metal is deposited on the substrate, and the at least one porous hydrophilic layer is deposited on the at least one layer of oxide(s) of at least one platinum group metal; (b) the at least one platinum group metal comprises or consists of palladium; (c) the vacuum deposited oxide(s) is(are) formed by reactive vacuum deposition of at least one platinum group metal in presence of oxygen; (d) the at least one porous hydrophilic layer comprises a mixture of at least one active metal with at least one active metal oxide; (e) the substrate is selected from metal, metal alloy, glass and ceramic substrates. (f) the at least one porous hydrophilic layer is optically black and/or absorbs IR radiation within the 1-14 micron wavelength range.
More preferably, the getter is characterized also by at least one of the following features: (i) the vacuum deposited mixture has a fractal surface configuration; (ii) the vacuum deposited mixture is formed by reactive vacuum deposition of at least one active metal in presence of oxygen under predetermined conditions adapted for the formation of the mixture, e.g., in an inert atmosphere at a pressure of between 10 −3 torr and 10 −2 torr, into which oxygen has been introduced at a pressure of from one to two orders of magnitude less than the inert atmosphere pressure.
In particular embodiments, the substrate may be in the form of a roll; and/or the substrate may be aluminum or titanium e.g. as foil, and/or the at least one active metal is selected from aluminum and titanium, and/or the vacuum enclosure forms part of an IR detection system.
In a modification of the vacuum enclosure and layered structure of the invention defined above, the “at least one layer of oxide(s) of at least one platinum group metal” is replaced by “at least one layer of substance(s) selected from the group consisting of platinum group metals and oxides thereof”. In other words, in place of the platinum group metal oxide(s) as described above, there may be substituted platinum group metal(s) or a mixture of such metal(s) and oxide(s). It will be appreciated that while the “at least one layer . . . ” just mentioned, when including oxide(s) may be formed by reactive vacuum deposition of at least one platinum group metal in presence of oxygen, when not including oxide(s) it may be formed by non-reactive vacuum deposition of at least one platinum group metal.
In a further modification of the vacuum enclosure and layered structure of the invention described in the preceding paragraph, the “at least one layer of substance(s) selected from the group consisting of platinum group metals and oxides thereof” is a platinum group metal layer or layers, and the substrate is constituted by a layer of hydrogen-absorbing transition metal(s) selected e.g. from Ti, Zr, Ta, V, Nb and Hf or any of their alloys, the transition metal layer being optionally deposited onto a further substrate.
A presently preferred structure comprises titanium substrate, e.g. a titanium foil substrate, on which is deposited a Pd and/or PdO layer, on top of which is deposited a black hydrophilic layer.
In another aspect, the invention provides a layered structure which comprises a thin-layer laminate vacuum deposited on a substrate, which has utility as a getter for undesired gaseous contaminants, wherein the laminate includes at least one layer of oxide(s) of at least one platinum group metal, and at least one porous hydrophilic layer provided that the structure includes one, two or three of the following features (A), (B) and (C), namely:
(A) the at least one layer of oxide(s) of at least one platinum group metal is deposited on the substrate, and the at least one layer of the porous hydrophilic layer is deposited on the at least one layer of oxide(s) of at least one platinum group metal;
(B) the porous hydrophilic layer comprises a mixture of at least one active metal with at least one active metal oxide;
(C) the porous hydrophilic layer is optically black and/or absorbs IR radiation within the 1-14 micron wavelength range.
The layered structure of the invention may also be additionally characterized by any one or more of the corresponding embodiments for the getter, as set forth above.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention, or parts or properties thereof are illustrated as follows.
FIG. 1 shows SEM images of the porous PdO layer.
FIG. 2 shows SEM images of various porous inorganic IR absorbing layers.
FIG. 3 shows two graphs of hemispherical reflectance of getter top layers.
FIG. 4( a ) shows a general view of a cold-shield with getter coating.
FIG. 4( b ) is a cross-section of a thin-layer laminate.
FIG. 5 illustrates an online production process.
FIG. 6( a ) shows a general view of a foil getter in roll form.
FIG. 6( b ) shows a cross-section of the foil getter of FIG. 6( a ).
DETAILED DESCRIPTION OF THE INVENTION
The present thin film getter comprises two vacuum deposited layers: a base layer of PdO and/or pure Pd and an upper, inorganic, highly porous hydrophilic layer composed of metal and metal-oxide admixtures. The outer layer can simultaneously serve as a wideband (1-14 micron) IR/light absorbing layer which exhibits a deep black color or its optical characteristics can be tailored to the application. This stacked layer structure deposited directly on the inner walls of the device, is intended to combine together both the optical absorbance and gettering capacity required inside the IR detector envelope, and eliminates the need for use of additional independent getter devices within this volume. The unique property of metallic palladium to absorb extremely large quantities of hydrogen at low temperatures is applied herein to produce an efficient getter structure. The getter under consideration realizes a unique combination of all or some of the following 5 mechanisms:
1. Hydrogen removal by chemical reaction with PdO base layer.
PdO+H 2 →Pd+H 2 O↑; (a)
2. Chemical absorption of hydrogen by pure metallic Pd formed in above reaction (a).
3. Physical absorption of water vapor (a) and other gases by the upper inorganic highly porous hydrophilic layer. This process consists of physical adsorption of water by the highly developed internal surface of this layer, and parallel chemical processes of metal oxide hydration.
4. Other gaseous contaminants of lesser importance than hydrogen—such as carbon oxides (CO 2 ; CO) and hydrocarbons—may be present in the evacuated space. These gases are also efficiently absorbed. Nitrogen, oxygen, and CO are absorbed by the pure metallic islands present in the pores of the upper hydrophilic layer and capture of some gases, such as carbon dioxide is promoted by presence of the water molecules inside the pores.
5. Hydrogen absorption by a pure metallic Pd layer and subsequent diffusion of the hydrogen into a sub layer of transition metal, e.g. titanium, from which the natural surface oxide has been removed. Hydrogen is stored within the bulk titanium effectively and irreversibly at operational temperatures of the device.
The above mentioned oxide reduction reaction (a) is exothermic and is also essentially irreversible; it proceeds easily within a wide range of temperatures from −55° C. up to 200° C. Palladium oxide is preferably used as the basis of getter structure because of cost considerations. However, other metals oxides, particularly those of the platinum group metals, such as Rh, Ru, Pd, Os and Ir, and alloys of platinum group metals, can be considered also.
The amounts of materials required for achieving the required performance and therefore the thickness of the deposited layers, depends greatly on the application and the total area of coated surfaces inside the hermetically sealed volume. For a standard IR detector enclosure the optimal thickness of platinum metal oxide layer e.g. PdO was found to be in the range of 0.1-10, e.g. 3-10 microns. Optimal thickness of the highly porous hydrophilic layer is 5-50, e.g. ˜25 microns. The gettering capabilities (capacities) in this case were found to be comparable to St 172 getters commonly used in similar applications.
FIGS. 1 a - b show SEM images of the PdO layer produced through the reactive sputter deposition of pure Pd onto the substrate. The enhanced porosity leads to an increased pores volume and promotes faster reaction with the hydrogen to produce H 2 O molecules.
FIGS. 2 a - d show SEM images of various inorganic metal+metal oxide admixtures with highly porous structures, obtained by the deposition process as the top layer of the getter. These nano-structured and non-stoichiometric layers are effective in capturing the H 2 O. These structures were obtained by a vacuum deposition process developed by Acktar Ltd—(a) Ultra Black™ coating, (b) Fractal Black™ coating, (c) Nano-tubes, (d) Nano-flowers.
The PdO layer was analyzed by XPS and also by EDAX as shown in Table 1. It was found, that all the Pd atoms inside the coating are presumably in the +2 oxidation state.
TABLE 1 PdO layer analysis by EDAX Coating Sample 1 Sample 2 EDAX ZAF Pd at. % 52.99 52.02 Quantification O at. % 47.01 47.98 Element Total 100 100 normalized Pd wt % 88.23 87.82 SEC Table: O wt % 11.77 12.18 Default Total 100 100 K ratio: 15 kV X-ray energy Pd 0.8483 0.8433 Tilt 0.00; Take off 46° O 0.0255 0.0265 Det Type: SUTW, res.: 128.6 Z values: EDAX ZAF Quantification Pd 0.9531 0.9516 Element normalized O 1.2658 1.2638 SEC Table: Default A values: Pd 1.088 1.0091 O 0.1714 0.1723 F values: Pd 1 1 O 1.0001 1.0001
The top nano-structured layer of the getter is typically black in appearance and has a dual functionality in the case of IR detection applications. In addition to providing the above mentioned gettering capacity; it also exhibits unique optical characteristics with increased absorbance (as well as high emissivity) in the IR range which is a typical feature required on internal surfaces of the detector cold-shield to eliminate stray light propagation.
FIG. 3 shows the hemispherical reflectance of two distinct types of such layers demonstrating the optical properties of the outer getter coating with nearly zero reflectance at 8.5-10 μm wavelengths. Alternatively—for other parts of the detector-dewar structure—the optical characteristics of the outer layer can be tailored appropriately.
The present getters, comprising preferably PdO and an additional water absorbing layer which is optically black and/or absorbs IR radiation within the 1-14 micron wavelength range, are produced exclusively by thin-film vacuum deposition techniques. The PdO layer is first deposited onto the preferred substrate by means of reactive sputtering in a technique which enhances the porosity and active surface area within the layer. Following the PdO deposition, the substrate enters a second process zone (within the same vacuum chamber or as a separate production step), where an additional layer is produced by a reactive evaporation of metal and metal oxide admixtures by a thermal evaporation process. See e.g. U.S. Pat. No. 6,764,712 (Katsir et al.), which describes and claims a method for increasing the surface area of a substrate, comprising the steps of: (a) placing the substrate in an inert atmosphere, having a pressure of between 10 −3 torr and 10 −2 torr, into which oxygen has been introduced at a pressure of from one to two orders of magnitude less than the inert atmosphere pressure; and (b) evaporating active metal(s) only, onto a heated substrate under the oxygen-containing inert atmosphere, whereby the product comprises a mixture of fractal surface structure including at least one active metal and at least one active metal oxide deposited on the substrate.
The second layer provides the H 2 O gettering capacity required and in addition it is designed to exhibit unique optical properties required for effective absorption of stray IR light inside the detector enclosure.
FIG. 4 a shows an image of a typical cold-shield used in an IR detector application where the above mentioned layers are applied onto the inner surface of the shield. FIG. 4 b shows a schematic cross section of the stacked layers that comprise the thin film getter on the inside of the shield. The separate PdO and metal/metal oxide layers can also be applied at different ratios and on separate parts or opposite sides within the same vacuum enclosure to satisfy specific applications.
Although typical getter applications require the deposition of the specified layers onto structured assembly parts as described above, the concept of this getter is also used to produce products for general applications by depositing the layers onto a thin foil substrate in a roll-to-roll process. Similar process steps are performed in-line inside a unique web coater which is capable of simultaneously performing all process steps onto both sides of the substrate, which is typically Ti or Al foil. The metallic foil substrate is processed in continuous rolls, which allows significant cost reduction through the high volume production process. FIG. 5 illustrates a scheme of an in-line layer deposition process carried out inside a vacuum chamber.
FIG. 6 a shows the product which is obtained by this process, where the black layer observed on both sides of the substrate is the outer metal/metal oxide layer responsible for the gettering of H 2 O molecules and the absorption of stray light and IR radiation. FIG. 6 b illustrates the stacked layers as applied onto the continuous roll of substrate material.
The invention will be illustrated by the following Examples.
EXAMPLE 1
A layer of palladium oxide to a desired thickness in the range 3-10 microns was deposited by reactive sputtering of pure palladium in an oxygen rich atmosphere with an Argon background onto either one or both sides of clean aluminum foil substrates held at a temperature of 300° C. and with pressure maintained between 0.3-1 Pa. Aluminum was then evaporated onto the palladium oxide surfaces of the substrates, held at the same temperature, by reactive thermal resistive evaporation, in an anhydrous inert atmosphere in presence of oxygen. The thus-produced Al/Al 2 O 3 layer has a fractal-like structure with a cauliflower-like morphology. The “cauliflower heads” are about 2 microns across. The “florets” are about 0.2 microns across, so that the surface is self-similar at least
on a distance scale from 0.2 microns to 2 microns. This is confirmed by the visual appearance of the surface. The Al/Al 2 O 3 surface is black matte (diffusely reflective), showing that this surface has a fractal-like structure on the length scale of the wavelengths of visible light. The following is an EDS elemental analysis of the Al/Al 2 O 3 surface: N 1.18%, O 30.43%, Al 66.38%, P 1.79% and Ar 0.22%. It follows from stoichiometry that 30.3% of the aluminum was in the form of Al 2 O 3 and 69.7% was in the form of aluminum metal.
The aluminum foil having deposited on one or both sides, sequential palladium oxide and Al/Al 2 O 3 layers is suitable for use as a getter (for hydrogen and water vapor, in particular) in high vacuum systems of special applications such as IR detectors. Alternatively, the sequential layers may be deposited directly on the inner surface (e.g. glass) of a potential high vacuum tube.
EXAMPLE 2
A layer of pure palladium to a desired thickness in the range of 100-600 nm was deposited by sputtering of pure palladium in an inert argon atmosphere onto either one or both sides of a titanium sheet, from which the naturally occurring surface oxide was removed and with pressure maintained between 0.1-1 Pa. Aluminum was then evaporated onto the palladium surface(s) of the substrates, by reactive thermal resistive evaporation, in an anhydrous inert atmosphere in presence of oxygen. The thus-produced Al/Al 2 O 3 layer has a fractal-like structure with a cauliflower-like morphology. The “cauliflower heads” are about 2 microns across. The “florets” are about 0.2 microns across, so that the surface is self-similar at least on a distance scale from 0.2 microns to 2 microns. This is confirmed by the visual appearance of the surface. The Al/Al 2 O 3 surface is black matte (diffusely reflective), showing that this surface has a fractal-like structure on the length scale of the wavelengths of visible light. The EDS elemental analysis of the Al/Al 2 O 3 surface is essentially as stated in Example 1.
The titanium sheet having deposited on one or both sides, sequential palladium and Al/Al 2 O 3 layers is suitable for use as a getter (for hydrogen and water vapour, in particular) in high vacuum systems of special applications such as IR detectors. Alternatively, the sequential layers may be deposited directly on the inner surface (titanium or other transition metal) of a potential vacuum enclosure.
INCORPORATION BY REFERENCE
The entire contents of all of the US Patents mentioned hereinabove are incorporated by reference herein.
ADVANTAGES OF THE INVENTION
The present invention has the advantages of miniaturization (and thus relatively low thermal mass), absence of particulation during entire life time of the detector, high vibration stability, large surface area and thus high sorption capacity at room temperatures, able to be activated at temperatures below 125° C., simplified construction and low cost. The present invention further combines gettering of (at least) hydrogen and water vapor with the potential for absorption of stray light.
Moreover, low temperature activation eliminates the need for electric connections through the dewar wall and reduces dewar design constraints resulting from the need to physically distance the getter surface from the detector elements. Also, the getter layer can be integrated with the internal low reflectance inorganic coating of cold shields and/or coated on internal dewar surfaces with appropriately tailored optical characteristics. Where appropriate, the gettering surface can be generated on a metal foil to be placed in the evacuated area.
It will be evident that in the layered structure/getter of the present invention, the functions of radiation absorber and gas absorber may be combined in the same unit, and that, moreover, in the IR region (1-14 micron wave-length) in particular, emissivity and absorbance may be tailored. Thus e.g. inside a cold shield there may be a laminate with a black hydrophilic layer having high emissivity (above 80%, typically ˜95%) and outside there may be a laminate with relatively low emissivity (5-40%, typically ˜10%).
Furthermore, the structure of the present invention can be produced continuously, without separate chemical precipitation, reduction and oxidation steps, and without any requirement for use of a binder and a curing agent therefor.
Although the invention has been described with respect to a limited number of embodiments, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the invention is intended to embrace all such alternatives, modifications and variations that fall within the spirit and scope of the appended claims. | The invention provides a vacuum enclosure which is defined by a wall having inner and outer surfaces, where the inner surface is in contact with the vacuum and the outer surface is in contact with ambient air. The vacuum enclosure is characterized by the presence therein of a getter for undesired gaseous contaminants. The getter includes a substrate (either integral with the inner surface or not) and, deposited thereon by vacuum deposition, a thin-layer laminate including at least one layer (α) of substance(s) such as platinum group metals and oxides thereof, and at least one porous hydrophilic layer (β). A corresponding layered structure having utility as a getter is also part of the invention. | 2 |
FIELD OF THE INVENTION
This invention relates generally to broadcasting streaming data over a network. More particularly, the present invention is a system for avoiding a single point failure when multicasting a data stream comprising video, audio and other data.
BACKGROUND OF THE INVENTION
Multicast streaming services provide for the continual feed of streaming data, including video, over a network to many different users. The most common application is streaming video across a network system. Audio streaming is another common application. However, these streaming application types are not intended as a limitation. Typically, a particular data stream is multicast from a single server over a network. This allows many people to receive and view the same program simultaneously.
If however, the server becomes unavailable, then the multicast stream which is being served from the server will also be unavailable, thus leading to an outage of service.
Increasingly, the lines between cable television service and serving a data stream over the Internet is becoming blurred. More and more, television-like content is being served to users of the Internet. This is becoming increasingly so in an era where bandwidth is increasing, and is readily available to Internet users. Today, Internet cable, DSL, and other types of high bandwidth lines are readily available to Internet users. Such users are demanding more and more content.
When a web based asset is used to stream video to Internet users, especially multiple users, there are generally two schemes that are employed. First, a unicast of the data stream is made to a single user. In a unicast situation, a single user connects to a website having program content. Upon demand, that program content is served by the web server to the individual user. When multiple users desire a particular program at different times, multiple unicasts of the data are made by the server. However, a single server can only serve a finite number of unicast streams of a given program content.
Multiple streaming servers are used to load balance unicast data to many individual users. If a particular server fails, each user suffers an outage, albeit of differing content initiated at different times. Frequently multiple streaming servers are used in order to achieve load balancing and to allow multiple unicast streams of the same web asset. This approach works well when an equal number of video streams are served from each of the servers. However, if any server goes down, the individuals who are being served from that server will have their service disrupted.
When a streaming server is distributing a video stream in a multicast mode (that is, simultaneous streaming of a video stream by multiple users), rather than in multiple unicast streams, the load on the server is relatively low. This is because a single stream per program is being broadcast by the server to multiple users, therefore multiple interactions with the server are not required for a single program. In a multicast situation, load balancing is not as much of an issue and therefore, multiple servers are not required. These relatively unused stream server resources can be used to increase the program availability by providing redundant servers of the same content.
What would be particularly useful is a system which allows for the unicast or multicast of a video stream with the reliability that is associated with redundancy in the system.
SUMMARY OF THE INVENTION
The present invention is a system and method for harnessing the relatively under utilized streaming servers as redundant servers to minimize user outage due to a server failure particularly under multicast mode.
It is therefore an objective of the present invention to improve the reliability of multicast streaming service over a video cable network.
It is yet another objective of the present invention to improve the reliability of multicast streaming service over networks serving clients.
It is a further objective of the present invention to improve the reliability of unicast broadcasts over client networks and over video networks.
It is a further objective of the present invention to introduce redundancy into the network serving multicast customers to improve reliability.
It is yet another objective of the present invention to ensure that service is not interrupted to cable and network clients who are receiving stream data applications.
The present invention is a system and method that is used in conjunction with redundant multicast servers to enhance the reliability of receipt of data stream desired. The use of two servers is the preferred embodiment although this is not meant as a limitation. More than two servers can be used although it is anticipated that there will not be a corresponding increase in reliability over the architecture that uses two multicast servers. One server broadcasts the primary stream. The other server broadcasts the secondary stream. The secondary stream data content is identical with the primary stream data content.
Each server multicasts the same content at the same time over the same enterprise network that is connected to the monitoring device of the present invention. An enterprise network may be a local area network, wide area network, intranet or any other network whereby the enterprise telecommunicates internally. For purposes of this application, the present invention is a system and method which includes a device that monitors for an adverse change of the primary multicasting server to utilize the secondary stream content when an adverse change is detected. An adverse change is a detected error which may range from corruption in the packet to the absence of the packet itself. This device multicasts the secondary stream content to the users when the primary stream server undergoes an adverse change, including failure. Hence, the device that monitors the two servers is termed a “failover” device.
As noted above, each server multicasts the same content at the same time over the same enterprise network connected to the failover device. The multicast stream from each server is assigned a different IP address and port number. The failover device is configured to select from one of the multicast streams and designates that stream as the primary stream. The failover device designates the second multicast stream as the secondary stream.
The failover device listens for both multicast streams. The device buffers the primary multicast stream packets as well as the secondary multicast stream packets. Under normal conditions, that is no adverse change is detected, the failover device takes a copy of the primary stream data packet to multicast. In the event of a primary stream adverse change, the failover device takes a copy of secondary multicast server to multicast. The failover device overwrites the IP address and Port number in the packet it will multicast with its own virtual IP address and virtual port number. This virtual IP header information replaces the real IP header information that was in the original data packet. The rewritten data packet is then multicast by the failover device. The program data content (other than the IP header information) multicast by the failover device is therefore unaltered from the source data packet. As noted above, the secondary multicast stream packets are buffered but not otherwise used until an adverse change from the primary stream packet is detected.
In this fashion, there is a minimal loss of content to the clients whether the adverse changes are continuous or occasional.
The system of the present invention can be used by any application that employs multicast streaming, including, but not limited to video and audio programming. Further, the present invention finds its best use for multicast traffic which does not have stringent synchronization requirements and which can tolerate a minimal loss of data. Video and audio streams are examples of the type of content that is well suited for this failover methodology.
It should also be noted that while the failover device buffers and multicasts the packets, the failover device itself does not synchronize the multicast stream that is being broadcast by the multiple servers of the present invention. This is separately synchronized between the multicast servers. It does, however, synchronize the packets of data that are to be subsequently multicast.
The failover device may use the packet count information present in the packet header to synchronize the packets received from the primary and secondary multicast servers. This synchronization method is one embodiment and is not meant to be limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the functioning of the failover device.
FIG. 2 illustrates the buffering and switching associated with the failover device.
DETAILED DESCRIPTION OF THE INVENTION
As noted above, the present invention comprises a failover device monitoring redundant streaming servers in order to ensure reliability and uninterrupted service for viewers of video programs.
Referring first to FIG. 1 , the functioning of the failover device is illustrated. Multicast server A 10 and multicast server B 12 , each multicast the same content over the same enterprise network 14 . The two multicast servers each constitute a Real Multicast transmitting a multicast IP address and Port (RMIPP). Each multicast server multicasts stream packets having IP headers associated with the address and port of the associated server. Each RMIPP is unique in order to avoid duplicate network traffic. Thus, in FIG. 1 , RMIPP-A represents the multicast channel from multicast server A over which a particular data stream is broadcast. The same video stream is multicast over RMIPP-B which represents the channel over which the same data stream is broadcast but, in this case, from multicast server B 12 .
The multicast content is received at the multicast stream failover device 16 which comprises logic to select one of the multicast streams as the primary stream and the other stream as the failover or secondary stream.
The failover device buffers the primary multicast stream packets in buffer 18 . Packets received from the secondary stream are buffered in buffer 20 (as more fully explained below). The failover device 16 can distinguish the source of the packets because the IP header information in each packet contains unique RMIPP. If there are no adverse changes detected in the primary data packet, the failover device overwrites the IP header information with its own Virtual Multicast IP address and Port number (VMIPP) in the primary stream packet. If an adverse change is detected, the failover device selects the secondary stream packet, overwriting the IP header information with its own VMIPP.
Thereafter the failover device multicasts the packet comprised of rewritten packets with the new virtual multicast IP address and port number. The source of the packet content is from the primary multicast server if there are no detectable adverse changes in the received packet. Otherwise the source is the secondary multicast server. The failover device will synchronize the packets from the two multicast servers such that the next packet multicast, regardless of the content source, is the packet that sequentially follows the last packet multicast. Thus, the multicast failover device forwards the content stream from either RMIPP-A or RMIPP-B where the IP header is rewritten as VMIPP.
Synchronization of the two video streams is carried out by the servers in communication with one another. Thus, the failover device performs a failover from one RMIPP to another RMIPP in the event that the primary RMIPP has evidence of some adverse change. As noted above, adverse change includes the loss of a packet from a multicast stream as well as corruption of the data. Two multicast sources are synchronized in time and have access to the same source data and programming instructions (either via a shared disk 8 or from independent replicas of the data). By virtue of this synchronization, the servers 10 , 12 multicast the same data (differing only in data source information) at the same time. Allowing both sources to be exact replicas makes configuration much simpler and does not require any additional development work to integrate into an architecture supporting Windows Media video multicasts.
Multicast sources 10 , 12 can be connected via separate physical ports or the same port depending on what mechanism is used to perform the actual filtering (L2/L3 sourceID filters vs physical port filters).
To provide accurate filtering logic, the system of the present invention optionally provides a Monitor 21 with access to the Programming data from the shared disk 8 (which is preferably in a reduced form which comprises the address and expected bitrate of every active multicast in a given time window).
An optional “sniffer” hub 19 provides a higher level of certainty to the monitor via a second NIC card. Capturing duplicates of all backnet 14 traffic provides the Monitor 21 with a guaranteed view of the backnet 14 status. The certainty comes from additional knowledge concerning whether data loss is truly occurring at the multicast sources versus at the net, switch, or NIC card. It also allows the Monitor 21 to know if switching between sources will actually help (i.e. it can also monitor the non-active (redundant-mode) source whose packets are not forwarded to the frontnet 15 for subsequent distribution to receivers 26 , 28 , 30 , 32 , and 34 ).
Multicast packets on a particular address are forwarded from only one source at a time (i.e. redundant packets from secondary source are filtered out—there is no packet rewriting). Note that while not necessary as long as receiving clients use buffers and can recognize duplicate and misordered packets, it is possible to provide packet-level synchronization with buffering and perhaps some knowledge of the packet format.
The Monitor 21 can control the failover mechanisms in the failover device 16 switch via exposed SNMP controls 24 . Threshholding logic in the failover device 16 dictates when such a failover should occur and failover may be at the individual multicast stream or entire multicast source level. Note that while an external Monitor 21 is illustrated, this is not meant as a limitation. For example, the same functionality of filtering duplicate packets based on L2/L3 sourceID or physical port can be implemented within the failover device 16 which can be more flexible since it does not rely upon the limited set of SNMP controls.
Windows Media player, whose capabilities are incorporated herein by reference in their entirety, is capable of handling duplicate and misordered packets via a buffering mechanism so as to overcome the lack of sync at the packet level that would become apparent when a stream is rolled over between sources.
Referring to FIG. 2 , the functioning and buffering of multicast content is illustrated. Primary streaming server 10 streams its data content using IP address X.X.X.X at port XX. Secondary streaming server 12 multicasts its data content, which is the same content and is synchronized with the content of primary streaming server 10 , using IP address Y.Y.Y.Y at port YY. As noted earlier, these video streams are synchronized with one another. Each video stream, from the primary streaming server and the secondary streaming server, is transmitted over the same enterprise network 14 to the failover device 16 .
The work that is sent to the customer, whether audio, video or other work, is the collection of data packets played in a strict sequence. While the packets may be delivered out of sequence, the playing device buffers the packets and orders the playing of the packets according to the packet sequence number found in the packet header area. For purposes of this description, packet content refers to the data viewed or heard by the end user, whereas header data includes IP addresses, port numbers and packet sequence numbers. As discussed below, packet sequence numbers are used to order the packets within the failover device buffers.
Multicast failover device 16 buffers the packet stream both from the primary streaming server 10 and from the secondary streaming server 12 . The packets from each are buffered such that the multicast failover device at a point in time has packet with sequence number X from the primary multicast stream and a packet from the secondary multicast stream with identical content and the same sequence number X in a second buffer. Further, the failover device 16 also has packet X+1, packet X+2, packet X+3, packet X+4, etc. from the primary multicast stream as well as packet X+1, packet X+2, packet X+3, and packet X+4, etc. from the secondary multicast stream.
While the multicast failover device does not synchronize the output of the primary and secondary streaming servers, 10 , 12 , it does synchronize the packets received so that the packets in the failover device buffers, at any point in time, contain the same data content packets in each buffer in the same order. Each buffer's content, assuming no packet defects, should be identical in the respective buffers at the same time.
One method for packet synchronization at the failover device is to use this packet sequence number contained in the packet's header. Each transmitting server numbers each packet. The failover device inserts the received packets into the buffer at a buffer index location corresponding to the packet's number. For example, packet number X from the primary server will be placed in the buffer for the primary server at index location equal to X.
Since programs are sufficiently large, the buffers are periodically recycled and overwritten. The packet number would be mapped by logic that converts the sequence number to an index value using a simple modulus mapping scheme. For example, if the buffers are reused every one hundred packets, the logic to map to the appropriate index would be to divide the sequence number by 100 (modulus 100 ) and insert the current packet at the index equal to the last two digits of the packet number. In this example the buffer indexes would range from 0 to 99. If the last valid packet seen by the failover device from the primary multicast system is, for example, packet with modulus M, then the failover device will continue broadcasting from the secondary stream buffer with packet with modulus M+1. In this fashion, clients will have continuity in their programs with no discernable interruption.
Failover device 16 rewrites the IP headers with a virtual IP address Z.Z.Z.Z and port number ZZ, which is then multicast to clients on the network.
The system and method where one program is being multicast in parallel with monitoring by a failover device that has remedial capability has been illustrated. Those skilled in the art will appreciate that multiple programs may be broadcast at the same time where each program is under the same redundancy and monitoring system using the same equipment as explained above. Thus the present invention should not be limited to the broadcasting of a redundant single stream of data but to the broadcast of multiple streams of data as well. Thus, the present invention is not intended to be limited to one program broadcast at one time. Multiple programs may be run simultaneously.
A system and method for multicast video stream failovers has been illustrated. It will be appreciated by those skilled in the art that other variations of the architecture illustrated will be possible without departing from the scope of the invention as disclosed. | A system and method for avoiding a single point of failure in the broadcast of streaming data. The system uses multiple redundant servers steaming the exactly same data to a failover device. The failover device buffers the steams into a primary and secondary data stream and automatically switches from the primary to the secondary data stream if it detects a corruption in the primary data stream. Since the buffered data packets of the two steams are identical and are synchronized, there is not outage for multicast receivers when the primary data source fails since there is a switch to exactly the same data in the next packet of the secondary data stream. | 6 |
RELATED APPLICATIONS
This application is related to co-pending application Ser. No. 11/426,687, entitled “Endpoint Activity Logging” and co-pending application Ser. No. 11/426,699, entitled “Unique Identifier Validation,” both of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to the field of network monitoring, and more particularly to the logging of access to and/or activity on a computerized network such as the Internet.
BACKGROUND
It is a usual practice for companies providing access to the Internet and for companies providing content and services on the Internet to generate logs of access and activity. Some examples of how logs are used are: for debugging and troubleshooting, detection and monitoring of abuse, statistical analysis, demographic analysis, report generation and other general business purposes.
One issue that arises with the storage of access and activity logs is the convenient and efficient maintenance of those logs. Entities that provide access to the Internet, and entities that make content and services available on the Internet, often have the triple responsibilities of (1) maintaining privacy, (2) maintaining the integrity of the services being provided, and (3) complying with all applicable laws regarding the disclosure of information. To fulfill the responsibility of maintaining privacy, the entity would ideally log as little information as possible. Any information maintained represents a liability to the entity generating the information in this regard since it represents a risk of disclosure and possible compromise of privacy.
To fulfill the second responsibility of maintaining the integrity of the services being provided, the entity needs to log certain types of information for certain periods of time. For example, enough information should be maintained long enough so that abuse can reasonably be detected over a reasonable period of time. Additionally, billing requirements may require certain information be maintained. This responsibility does not necessarily mean complete logs must be maintained. In certain cases, the entity only needs summary information, and/or only needs to maintain the information for a limited period of time. For example, an entity proving access to the Internet may want to maintain for over a year the number of minutes connected on a certain day, while the specific IP address in use on that day and the specific port numbers used may only be needed for days or weeks.
The third responsibility is to comply with all applicable laws for the jurisdiction under which the entity operates. In some cases, there are no laws that require the preservation of logging information, in which case the logged information would be governed by other concerns. In other cases regulations may require that certain types of information may be maintained for a specific period of time. Another type of legal responsibility that arises in certain circumstances is not a requirement a priori that certain information be maintained, but that all information that is under the custody or control of the entity is produced at the time a subpoena is received. Since responding to subpoenas is expensive and time consuming, it is most efficient to maintain custody and control only of that information that is required for business reasons or legal reasons.
Thus, it can be seen that there is a balance in what information is logged, how it is accessed and for how long it is maintained. In many cases merely maintaining complete logs indefinitely is not an efficient or appropriate mechanism for maintaining these multiple responsibilities. What is needed is an improved method of maintaining and accessing logs that allows log generating entities to more cost effectively balance their multiple responsibilities.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a method and apparatus for remote logging of access to and activity on a computerized network. Logging information is transmitted to a remote log repository and is not maintained by the local log generating machine. After the logging information is stored in the remote repository, the access to the information is controlled by a specific policy that governs the type of information and the time period during which the information is available. No access is provided to information outside the bounds of the access policy. Preferably the remote log repository is outside the jurisdiction of relevant authorities. This allows the access policy between the log generating entity and the log repository to dictate precisely the information that is under the control of the log generating entity. The use of a remote log repository and a specific access policy affords flexibility to the log generating entity in balancing its multiple responsibilities and makes responding to subpoenas cost effective and efficient.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a prior art interconnection and logging mechanism.
FIG. 2 illustrates a prior art interconnection and logging mechanism.
FIG. 3 illustrates activity logging in an embodiment of the present invention.
FIG. 4 illustrates communication and logging events in an embodiment of the present invention.
FIG. 5 illustrates activity logging in an embodiment of the present invention.
FIG. 6 illustrates MAC address registration and validation.
FIG. 7A illustrates remote logging across a jurisdictional boundary.
FIG. 7B illustrates remote access to log information across a jurisdictional boundary.
FIG. 8A illustrates encryption and decryption management for remote logging and reporting.
FIG. 8B illustrates an alternative embodiment of encryption and decryption management for remote logging and reporting.
DETAILED DESCRIPTION
FIG. 1 illustrates a typical environment in which a Web Server on the Internet logs activity. User 110 represents a user operating a browser and connected to the Internet 120 . Web Server 130 is a web server connected to the Internet 120 and storing web pages for public viewing. When User 110 , through the browser running on their computer, requests a web page stored on Web Server 130 , a HTML document is delivered to the browser and displayed to User 110 . In addition, a record is made of this activity in Access Log 140 . A web server activity log will typically contain information regarding the access, but not the actual content of the access itself. For example, a web server log generally records the originating IP address, the name of the document that was requested and the number of bytes that were transferred to the client machine. It is common to record in an access log file a record of each access.
The Apache Software Foundation is an organization that supports an open-source web server known as Apache HTTP Server Project. Documentation and software for the Apache HTTP Server Project are located at http://httpd.apache.org. The Apache web site indicates that Apache has been the most popular web server on the Internet since April 1996, and as of 2005 represents more than 70% of the web sites on the Internet. The document entitled “Log Files” available on the Apache web site at: http://httpd.apache.org/docs/2.2/logs.html, incorporated herein by reference, describes several log file formats. Log file formats in use today, such as those described in the document referenced above, record the originating IP address of each machine that requests a document.
In cases such as FIG. 1 in which User 110 is directly connected to the Internet 120 , the originating IP address is sufficient to identify the machine at which the request originated. However this is not the case in other scenarios. FIG. 2 illustrates a more common situation in which User Computer 210 is located on Local Network 220 behind NAT Gateway 230 . Typically the IP addresses in use on Local Network 230 are unregistered or un-routable addresses that can be used within an enterprise but cannot be used on the public Internet. Un-routable addresses are addresses that have been set aside in the ranges 10.0.0.0 to 10.255.255.255, 172.16.0.0 to 172.31.255.255 and 192.168.0.0 to 192.168.255.255. IP addresses in this range may be freely used within a private network as they are guaranteed to be unused and unusable on the public Internet. NAT Gateways are used to convert packets coming from un-routable IP addresses into packets with addresses valid on the public Internet. This scheme is utilized to allow many machines to be used on an internal network without tying up as many public IP addresses, which are global resources.
In particular, NAT Gateway 230 operates a function known as Network Address Translation (NAT), which translates internal network addresses into external network addresses. Thus, a packet originating from User Computer 210 is translated by NAT Gateway 230 into another packet with a different source IP address and transmitted to Web Server 260 across the Internet 250 . A return packet from Web Server 250 to User 210 will be transmitted to NAT Gateway 230 , which will translate the packet into a different packet with the destination IP address for User Computer 210 . The operation of NAT Gateways on the Internet is well known and in wide use today.
Frequently internal networks allocate IP addresses using a protocol known as DHCP. This requires the use of a DHCP Server 240 attached to Local Network 220 . Briefly, the DHCP protocol involves the allocation of IP address upon request by machines on the local network. For example, when User Computer 210 powers up, it will request an IP address and DHCP Server 220 will allocate one. This operation is known as a “lease” and generally has an expiration time associated with it. The DHCP protocol generally requires periodic communication between User Computer 210 and DHCP Server 240 in order for User 210 to continue to be allowed to use the IP address to which it has been granted.
Many machines may exist on Local Network 220 , and there may be multiple NAT Gateways within a large enterprise. This means that a request for a document on the Internet originating from a browser on a user's machine may be translated multiple times before it reaches the web server that is hosting the document. Thus, Access Log 270 that is recorded by Web Server 260 is insufficient to identify the specific machine that actually made the request.
FIG. 3 illustrates activity logging in an embodiment of the present invention. User Computer 310 is connected to Local Network 320 which is connected to NAT Gateway 330 and DHCP Server 340 . In most embodiments, NAT Gateway 330 and DHCP Server 340 will be implemented on the same physical machine and there will only be one network connection from that machine to Local Network 320 . NAT Gateway 330 is coupled to the Internet 350 , which is in turn coupled to Web Server 360 . Access Log 370 receives information from Web Server 360 , NAT Gateway 330 and DHCP Server 340 . By combining information from all three sources as described in more detail below, activity logs can be generated that uniquely associate User Computer 310 with activity on Web Server 360 .
Access Log 370 is shown in FIG. 3 as a single unit for illustrative purposes. The storage of activity data can be distributed across multiple machines and the physical location or locations of the log storage can vary. Web Server 360 , NAT Gateway 330 and DHCP Server 340 can locally store activity information and then periodically transfer it to a central location, or in alternative embodiments the activity information may be transmitted immediately to a central repository. In still other embodiments, the activity information may never be stored together in one physical location but may be maintained separately and controlled by separate entitles. It will be appreciated to those of skill in the art that as long as the requisite information is recorded in some fashion, there are many alternatives to how, when and where the information is stored.
One feature of an embodiment of the present invention is that Web server activity can be associated with an individual user and/or an individual computer, through for example a MAC address. Every computer having an Ethernet interface in principle has a globally unique MAC address, which is a 48-bit address associated with the Ethernet interface and used as the source address for Ethernet frames transmitted from that interface. The MAC address is created by the manufacturer at the time the interface is created. Alternative identifiers can be used to uniquely identify a particular user or computer. For example, some central processing units (CPUs) have unique processor IDs that are created by the microprocessor manufacturer and are globally unique and cannot be changed by the user.
It will be appreciated to those of skill in the art that other forms of unique identifiers can be used, including a phone number, address, bank account number, credit card number, social security number, license plate number, or the like. It is also the case that the identifier need not uniquely identify the user or computer throughout the entire world. In certain embodiments it may only be necessary to identify the user or computer within a certain group or it may only be necessary to narrow down the user or computer into a relatively small group.
In order to associate the MAC address used by User Computer 310 with activity that occurs on Web Server 360 , it is desirable to record the association between the MAC address used by User Computer 310 and an IP address allocated by DHCP server 340 . Additionally, it is desirable to record the alias link between an internal and external IP address that is created by NAT Gateway 330 . This is explained in more detail below.
FIG. 4 illustrates communication and logging events in an embodiment of the present invention. User Computer 410 exchanges messages with DHCP/NAT Gateway 420 , which in turn is coupled to Remote Server 430 . FIG. 4 illustrates the types of information that are logged in an embodiment of the present invention in order to associate User Computer 410 with remote activity. When User Computer 410 is first connected to a local network on which DHCP/NAT Gateway 420 is also connected, it communicates with DHCP/NAT Gateway 420 in order to get an IP address to use. The DHCP protocol is typically used to perform this function, although there are alternative dynamic IP address allocation protocols that can be used. When a dynamic IP address is allocated to User Computer 410 , this is known as a “lease” and will typically last for a defined period of time at which point it needs to be renewed through further exchange of messages.
FIG. 4 illustrates a simplified exchange of DHCP messages between User Computer 410 and DHCP/NAT Gateway 420 for illustrative purposes. Those of skill in the art will appreciate that the DHCP protocol involves other messages. In the example of FIG. 4 , first User Computer 410 , using the MAC address 00:10:c6:cf:94:c6 requests an IP address from DHCP/NAT Gateway 420 . Next, DHCP/NAT Gateway 420 allocates dynamic IP address 192.168.0.11 to User Computer 410 and sends an acknowledgement message to User Computer 410 with this information. At this point, the lease of IP address 192.168.0.11 to MAC address 00:10:c6:cf:94:c6, illustrated by information block 440 , is recorded. An actual sequence of DHCP messages that represents this exchange is typified by the following:
User→Server: DHCPDISCOVER from 00:10:c6:cf:94:c6
Server→User: DHCPOFFER on 192.168.0.11 to 00:10:c6:cf:94:c6
User→Server: DHCPREQUEST for 192.168.0.11 from 00:10:c6:cf:94:c6
Server→User: DHCPACK on 192.168.0.11 to 00:10:c6:cf:94:c6
The establishment of a “lease” represents the grant of an IP address to a particular machine identified by an Ethernet address. In this case the IP address granted is an internal, un-routable address, which can be used on a local network but cannot be used on the Internet. DHCP servers can typically be configured to allocate either internal or external IP addresses, and can allocate from a pool of IP addresses, or can be configured to associate particular IP addresses with particular MAC addresses.
An example of software that performs the DHCP functionality is the dhcpd daemon (a daemon is a computer program that runs in the background) that is a standard utility on may Unix systems. The dhcpd daemon is configured to listen on certain interfaces and to respond to broadcast messages from machines requesting IP addresses. Some implementations of dhcpd can be configured to automatically log the granting of leases and the expiration of leases. In one embodiment of the present invention, the dhcpd daemon is configured to generate this information, and/or is modified to transmit this information to another host, immediately or periodically.
The next sequence illustrated in FIG. 4 relates to network address translation (NAT). Because User Computer 410 is utilizing an un-routable IP address, this address needs to be translated to an external IP address before packets can be sent over the Internet. This is the job of the NAT gateway. The establishment of an association between an internal IP address and port number to an external IP address and port number is known as an “alias link.” Because there may be many internal machines communicating with the same remote host, it may be necessary for the NAT gateway to change the port number from the one utilized by User Computer 410 . Because TCP connections are uniquely identified by source and destination IP address and source and destination port numbers, multiple connections from the same IP address can be established to the same destination port number as long as the source port number is different for each connection.
In the example illustrated in FIG. 4 , User Computer 410 sends a packet to set up a connection to a remote Web server at IP address 66.102.7.104, port 80. The source IP address for User Computer 410 is 192.168.0.11 and the source port number is 1534. Upon receiving the packet from User Computer 410 , DHCP/NAT Gateway 420 establishes an alias link, rewrites the outgoing packet and sends it to the Internet. Because the un-routable address used by User Computer 410 is not usable on the Internet, the source address for the outgoing packet is replaced with the source address for DHCP/NAT Gateway 420 , which in this example is 63.198.33.202. FIG. 4 illustrates that DHCP/NAT Gateway 420 associated port 3541 with User Computer 410 source port 1541. At this point the alias of source IP address 192.168.0.11 to external IP address 63.198.33.202, port 3541 is recorded, as illustrated by information block 450 .
An example of software that performs NAT functionality is the natd daemon that is a standard utility in many Unix systems. In some implementations natd relies on a library known as libalias which performs the function of maintaining a table or database of IP number and port number associations. The libalias library code adds and deletes alias links as needed. In one embodiment of the present invention, the libalias library is modified to log certain alias links to a file and/or to transmit this information to another host, immediately or periodically.
The next sequence illustrated in FIG. 4 is the receipt of the packet by Remote Server 430 and the return of a packet to DHCP/NAT Gateway 420 , which subsequently returns a packet to User Computer 410 . Remote Server 430 could be a Web Server, an Email Server or any other server on the Internet for which activity logging is desired. In the example shown in FIG. 4 , Remote Server 430 , which is at IP address 66.102.7.104 receives a packet to port 80 from source IP address 63.198.33.202, port 3541. Remote Server logs the access as illustrated in information block 460 .
Web server logging is well known the field and it is common for Web servers to log activity. A typical log entry consists of the source IP address and the document requested along with other information. The Apache HTTP Server, described above, defines a “Combined Log Format” that can be utilized to configure the Web server for what information is logged. An example entry in the Combined Log Format is shown below:
127.0.0.1-frank [10/Oct/2000:13:55:36-0700] “GET/apache_pb.gif HTTP/1.0”200 2326 “http://www.example.com/start.html” “Mozilla/4.08 [en] (Win98; I; Nav)”
The fields in this entry are as follows: 127.0.0.1 is the IP address of the client that made the request of the Web server, the dash is a null field in place of the RFC 1413 identity of the client, frank is the user ID of the person requesting the document as determined by HTTP authentication, the date field between brackets is the date and time that the request was received, the next field between quotes is the request that was received from the remote host, 200 is the status code that the Web server sent back to the client, 2326 is the size of the object returned to the client in number of bytes, the next field between quotes is the site that the client reports having been referred from, and the last field between quotes is the identifying information that the client browser reports about itself.
Note that a Combined Log Format entry such as illustrated above is not in general sufficient to uniquely identify an individual user. In particular, the source port number is not typically logged. Because many clients may be connecting to the Internet behind a single NAT gateway, in many circumstances the only way to distinguish an individual user it to log the source port number of the HTTP request. In a preferred embodiment of the present invention, the Web server software running on Remote Server 430 is modified to log the source port number of each HTTP request in addition to other information, and to send this information to a log file, and/or to transmit this information to another host, immediately or periodically. When the source IP address and source port number are correlated with the alias link information and with the IP to MAC address association, it is possible to associate a particular user with activity that occurs on a remote server.
Another form of Remote Server is an email server. A typical email transmission from a user to a recipient on the Internet involves a user's computer contacting a local SMTP relay on port 25, sending the email and closing the connection. Subsequently the local SMTP relay consults the DNS (domain name system) to determine the appropriate remote email relay for the domain name of each recipient of the email. If properly configured, the DNS zone for the destination domain will contain an “MX Record” which will specify the machine or machines on the Internet who will accept email for that domain. The local SMTP relay then contacts one of the machines indicated in the MX Record on port 25 and delivers the email message. Many if not most SMTP relays are configured to generate logs of sent and received email messages. The format of a log entry depends on the software used and the version of that software. A format for sendmail which is a software program that performs SMTP relay functions and is a standard component of many UNIX systems is shown below:
<date><host>sendmail[pid]: <qid>: <what>=<value>, . . .
Included in each log entry is a date stamp, the name of the host generating the information, the process ID for the running process, a queue ID and a comma separated list of parameter/value pairs. One of the parameter/value pairs commonly logged is the name and IP address of the remote host the email is being received from or is being sent to. For example, an entry in a log file might contain the following parameter/value pair: “relay=floozy.zytek.com.[63.198.33.206]” indicating that email was received from the IP address 63.198.33.206, having the name floozy.zytek.com.
In some cases it may not be important to log more that just the IP address of the machine sending an email, since email relays typically receive email directly from other email relays, or from trusted users. However, for the same reasons noted above for Web servers, this information is not in general sufficient to specifically identify an individual computer. In particular, the source port number is not typically logged. Because many clients may be connecting to the Internet behind a single NAT gateway, in many circumstances the only way to distinguish an individual computer it to log the source port number of the incoming SMTP connection. In a preferred embodiment of the present invention, the sendmail software running on Remote Server 430 is modified to log the source port number of each incoming SMTP connection in addition to other information, and to send this information to a log file, and/or to transmit this information to another host, immediately or periodically. When the source IP address and source port number are correlated with the alias link information and with the IP to MAC address association, it is possible to associate a particular computer with activity that occurs on a remote server.
In certain embodiments of the present invention, it may not be necessary to record the IP to MAC address association at the time the lease is generated by the DHCP Server. Instead, this information may potentially be generated at the same time the alias information is generated. This is because the packet that is received by the DHCP/NAT Gateway 420 may contain the source Ethernet address of User Computer 410 . In this case, DHCP/NAT Gateway 420 can just look at the source Ethernet address and record this as the MAC address associated with the source IP address that is also in the packet. In this case, the information contained in information block 440 and the information contained in information block 450 are combined into a single entry created at the same time by DHCP/NAT Gateway 420 . However this implementation is not always possible because in some embodiments, the source Ethernet address of the packet received by DHCP/NAT Gateway 420 is not the original source Ethernet address of User Computer 410 . This could be the case if there are intervening routers or other devices between User Computer 410 and DHCP/NAT Gateway 420 . There may also be situations, as discussed below, where multiple NAT gateways are employed between the user originating a packet and the machine that is ultimately responsible for delivering that packet to the Internet.
FIG. 5 illustrates activity logging in an alternative embodiment of the present invention. User Computer 510 is connected to Wireless Local Network 520 which is connected to NAT Gateway 530 and DHCP Server 540 . In most embodiments, NAT Gateway 530 and DHCP Server 540 will be implemented on the same physical machine and there will only be one wireless network connection from that machine to Wireless Local Network 520 . NAT Gateway 530 is connected to Wired Local Network 550 , which is in turn connected to NAT Gateway 560 . NAT Gateway 560 is coupled to the Internet 570 , which is in turn coupled to Web Server 580 . Access Log 590 receives information from Web Server 560 , NAT Gateway 560 , NAT Gateway 530 and DHCP Server 540 . By combining information from all four sources as described in more detail below, activity logs can be generated that uniquely associate User Computer 510 with activity on Web Server 580 .
The interconnection illustrated in FIG. 5 is more complicated than the interconnection illustrated in FIG. 3 because packets from User Computer 510 go through two NAT Gateways before reaching the Internet. This means that a first un-routable address may be used on Wireless Local Network 520 , these packets may be translated into packets utilizing a second un-routable address and sent between NAT Gateway 530 and NAT Gateway 560 . Finally, NAT Gateway 560 translates the packets from the second un-routable address to an external IP address for use on the Internet. Traceability back to User Computer 510 requires that the association between the user and the first un-routable IP address be recorded, that the alias link between the first and second un-routable addresses be recorded and that the alias link between the second un-routable address and the external IP address use by NAT Gateway 560 be recorded. The process of logging information in the interconnection of FIG. 5 is similar to that described above in connection with FIG. 3 and FIG. 4 with the addition of a second NAT Gateway.
As explained above, it may be possible for NAT Gateway 530 to record the alias link information as well as the MAC address to IP address association since it receives packets directly from User Computer 510 . In this case, only two sources of information, NAT Gateway 530 and NAT Gateway 560 are needed to associate User Computer 510 with packets being transmitted on the Internet.
As explained above in connection with FIG. 3 , Access Log 590 is shown as a single repository for illustrative purposes. The repository may be distributed and the correlation of the multiple pieces of information necessary to establish the identity of activity need not be actually performed until needed. For example, since the activity known to Web Server 580 is under the control of the entity operating the Web site or sites associated with Web Server 580 , it may be stored separately from the other information. Similarly, the access information known to the NAT gateways and the DHCP servers are typically under the control of the entity who provides access of the user to the Internet, which may be a different entity form that operating Web Server 580 .
In some cases, it may be sufficient that the information necessary to correlate a specific user with specific Internet activity is available if and when necessary. Thus, the actual correlation is not performed unless required. It may be the case that the entity providing access of a user to the Internet protects the alias link and IP lease information unless required to provide it by a Court or law enforcement official, or dictated by an internal investigation. In some cases the entity providing access of a user to the Internet may be required to preserve the alias link and IP lease information, either by laws governing the entity in whatever jurisdiction they operate, or by contract dictated by the Internet service provider they connect through.
One issue that can arise when logging MAC address to IP address associations, such as through a DHCP lease or other address allocation mechanism, is the validity of the MAC address or other identifying information that is utilized by the user. Some Ethernet interfaces can be re-programmed by the user to set the MAC address to an arbitrary value not set by the manufacturer. This facility would allow the user to masquerade as an arbitrary MAC address, which in some cases would defeat the purpose of uniquely identifying the machine and/or user that is connected. For example, a user wishing to remain completely anonymous could configure User Computer 510 to utilize an arbitrary MAC address and connect to Wireless Local Network 520 , and subsequently to the Internet 570 . The same is true of any ID number used to identify the user if the number can be selected arbitrarily by the user. One way to address this issue is to require identifying information to be validated.
In some cases of public access to the Internet, user authentication takes place at the application level where users must type in user names and passwords. In such a case, it can be relatively simple to associate MAC addresses in use and/or allocated IP addresses with individual users. In this case, the related user account can be logged along with the other access information, allowing for possible later association to an individual. In this case, it may not be necessary to validate the MAC address in use, since the user is being identified through other means. In cases where there is no explicit user identification, or where it is important to further validate the access information, identification validation can be performed. Identification validation is one aspect of an embodiment of the present invention and is described below.
The purpose of identification validation is to guarantee that an association can be made between access to and/or activity on a local or wide-area network such as the Internet and an individual user, location, piece of equipment, etc. There is usually a tradeoff between security and privacy in such circumstances. While the anonymity of certain types of access and activity on the Internet is desirable and important, for other types of access and activity, it is also desirable and important that individuals responsible can be identified. The use of a carefully designed identification authentication system can appropriately balance these competing concerns. For example, information sufficient to identify access or activity can be maintained, while safeguards can be put in place to ensure that only in specific cases (such as a Court Order or Subpoena) would the information be made available. In another example, this information could be placed in the hands of an independent third party, who would provide the information under specific guidelines.
FIG. 6 illustrates MAC address registration and validation. MAC Address Registrar 600 is responsible for receiving a MAC address 610 and producing a signed version of the MAC address 615 . MAC Address Validator 650 is responsible for receiving an encrypted and signed MAC address 680 and validating the MAC address to generate a validation status 690 . The registration/validation process of the present invention is based on the use of public key cryptography. Public key cryptography is based on a matched pair of keys, one used to encode information and one used to decode information. By keeping one of the matched keys private and making the other public, the functions of authentication and encryption can be realized.
MAC Address Registrar 600 receives a MAC address 610 and signs it at 620 and produces a signed MAC address 615 . The Sign function 620 utilizes a Private Key 625 of MAC Address Registrar 600 . The use of a private key accomplishes the function of authentication since one can verify using Public Key 630 that the signed MAC address was produced by MAC Address Registrar 600 . The mathematics of the matched key pairs make it computationally infeasible to generate Private Key 625 knowing only Public Key 630 . Thus, it is impractical to generate a signed MAC address 615 without access to Private Key 625 . This means that Private Key 625 should be maintained in confidence by MAC Address Registrar 600 . There need not be a single MAC Address Registrar, but in embodiments of the present invention there may be many. Indeed any entity responsible for granting access to the Internet may chose to maintain a separate MAC Address Registrar.
An Ethernet MAC address is 48-bits in length. The purpose of a MAC Address Registrar 600 is to associate a MAC address with a known user, and potentially to verify the MAC address based on other criteria. This may be done, for example, by referring to the manufacturer and model of the hardware in use, by consulting a database of known MAC addressees, or by consulting a database of registered MAC addresses. Once the MAC address provided to the Registrar is verified, a signed version of the MAC address is generated. Because an arbitrary MAC address is usable to someone who can reprogram their Ethernet adapter, any signed MAC address would be usable to someone wishing to bypass the MAC address registration process. This means that it is desirable for MAC Address Registrar 600 to utilize enough bits in its signature so that it is impractical to guess signed MAC addresses even for arbitrary MAC addresses. The analysis needed to determine the number of bits needed to guarantee a certain level of impracticality based on available computational resources is known to those of skill in the art.
User 640 is responsible for delivering MAC Address 610 to MAC Address Registrar 600 and for saving the signed version of the MAC Address 615 . Preferably the transmission of the signed MAC Address 615 occurs over a secure channel. This is because if someone eavesdrops on this process, they could masquerade as User 640 by utilizing the MAC Address and signed MAC Address. A variety of techniques are possible to secure the transmission of signed MAC Address 615 to User 640 . In some embodiments, this process may occur over a private network. MAC Address Registrar 600 may be operated by an equipment manufacturer, distributor or reseller and may register MAC Address 610 before delivering it to a user. In other embodiments, an HTTP SSL connection is utilized to transfer Signed MAC Address 615 over an encrypted connection between MAC Address Registrar 600 and User 640 . It is appreciated by those of skill in the art that there are a variety of other techniques to securely transfer the Signed MAC Address 615 across a public network. Once Signed MAC Address 615 is delivered to User 640 , it is ideally stored in a manner inaccessible to unauthorized software running on the user's machine. This is needed to prevent malware running on the user's computer from retrieving the signed MAC address so that it could masquerade as the user. There are a variety of ways to accomplish this secure storage, including the use of passwords and additional encryption. In an alternative embodiment, Signed MAC Address 615 is stored internal to an embedded microcontroller, such as on a smart card or within an Ethernet adapter. In this case, once the embedded system is programmed with the signed MAC address, the address cannot be retrieved through an analysis of software and storage on the user's computer.
The validation process depicted in FIG. 6 begins with the use of a Public Key 670 of MAC Address Validator 660 delivered to User 640 at input 650 . The use of public key encryption during the validation process guarantees that the Signed MAC Address 615 is not intercepted by an eavesdropper. This would allow such an eavesdropper to masquerade as User 640 . In one embodiment, Public Key 670 is delivered over a secure channel to User 640 . This is desirable to avoid a Man-In-The-Middle attack, in which an intermediary intercepts Public Key 670 and replaces it with their own public key. In some embodiments, Public Key 670 is delivered to User 640 at the same time as Signed MAC Address 615 by MAC Address Registrar 600 . This may be convenient in situations where MAC Address Registrar 600 is operated by the same entity that operates MAC Address Validator 660 . In this case, Public Key 670 could be stored in the same manner as Signed MAC Address 615 , including on a smart card if such a facility is used. In another embodiment, Public Key 670 is signed by a known Certificate Authority, the public key for which is previously known to User 640 . In this manner, User 640 can verify that the public key being input at 650 is indeed the public key for MAC Address Validator 660 . Those of skill in the art will appreciate that there are alternative mechanisms to deliver a public key to User 640 and to authenticate MAC Address Validator 660 . In order to protect the confidentiality of Signed MAC Address 615 , it is important to ensure that User 640 only encrypts it with keys from entities authorized to receive it.
In order to prevent a “replay” attack, in which an eavesdropper listens to the transmission of an encrypted signed MAC address, it is useful to combine the signed MAC address with a number used once or “nonce.” An example of nonce is a time stamp of sufficient length and granularity. Another possible implementation would be for MAC Address Validator 660 to generate a random number internally and send it to User 640 for combination with the signed MAC address. When MAC Address Validator receives the encrypted and signed MAC address at 680 , decryption and authentication is performed in box 665 using Private Key 675 and Public Key 630 , received at input 655 , and a validation status 690 is produced. MAC Address Validator 660 utilizes Public Key 630 of MAC Address Registrar to authenticate the MAC Address. In a preferred embodiment, the delivery of Public Key 630 to MAC Address Validator 660 occurs on a secure channel, to prevent an attack in which a signed MAC address is faked according to keys not belonging to MAC Address Registrar 600 . In some embodiments, MAC Address Registrar and MAC Address Validator are co-located and operated by the same entity.
The above description has been with regard to MAC addresses, but it equally applies to any form of identification that can be represented in digital form. The functions described with respect to User 640 can be performed by hardware or software or any combination. These functions may be implemented by software running on a user's computer, workstation, portable hand-held computer or cell phone. The functions may also be performed by dedicated hardware and firmware, such as in a smart card. In some embodiments, some or all of the functionality described in connection with User 640 is built into a network interface card by the manufacturer and transparent to the user. For example, an Ethernet card could be pre-registered with Signed MAC Address 615 and Public Key 670 could be pre-installed. In order to validate, the Ethernet card merely encrypts the signed MAC address with a timestamp and makes it available to higher level software, which can then include this number during DHCP registration. In this case the validation of the MAC address is completely transparent to the user and would not affect implementations that do not rely on this feature. In some embodiments the encrypted and signed MAC address could be made part of the DHCP protocol, in which case the DHCP server could be modified to communicate with MAC Address Validator 660 before granting an IP address lease.
In an alternative embodiment, a different protocol could be used after an IP address lease but before packets are accepted by the NAT gateway. For example, an encrypted and signed MAC address could be sent to a machine on the local network on which it is installed, or the NAT gateway responsible for that network could accept the encrypted and signed MAC address and communicate with MAC Address Validator 660 before granting the opportunity to forward other packets.
In other embodiments, a user may carry a portable smart card that can be used for authentication for use with any computer. In this case the actual MAC address used by the computer is not used for user authentication, but instead other identifying information that has been previously registered.
In the embodiments of the present invention discussed in connection with FIGS. 3 , 4 and 5 above, it was illustrated how logging information can be generated sufficient to allow individual computers to be identified. The discussion in connection with FIG. 6 illustrates how computer or user identification can be validated. In one embodiment, the validation status 690 generated by MAC Address Validator 660 is logged along with the lease information such as that contained in information block 440 . A DHCP server, or other entity responsible to associating MAC addresses with IP addresses, could be modified to require additional information from a client computer and validate that the MAC address in use has been properly registered. Note that NAT/DHCP Gateway 420 need not know anything about the user or have access to the registration information, but merely needs to know from MAC Address Validator 660 that the MAC address in use by Client Computer 410 is valid. In this case, Validation Status 690 is merely an affirmative result transmitted to a DHCP Server or NAT Gateway. DHCP/NAT Gateway could then log an authorization code or an authentication string to prove that validation had been performed. In other embodiments, identification validation is done at the time an alias link is created and logged in connection with information such as that contained in information block 450 .
As noted above, there is a balance in what information is logged, how it is accessed and for how long it is maintained. It most cost effective for an entity that generates logging information to carefully design a system that appreciates the conflicting goals and responsibilities. Because merely maintaining complete logs is often not an efficient or appropriate mechanism, it may be desirable to have a remote log repository that is outside the direct control of entity that generated the logs and is outside the jurisdiction of entities that may require disclosure of information.
FIG. 7A illustrates an embodiment of a remote log repository. Access logs, such as those described above are generated by Firewall/Gateway 710 and delivered across secure connection 725 to Log Repository 735 . Similarly Web Server 715 generates Web activity logs and Mail Server 720 generates email activity logs and delivers them across Secure Connection 725 to Log Repository 735 . In certain embodiments of the present invention, Log Repository is across Jurisdictional Boundary 730 from the machines that generated the logs. Logging information may or may not be combined, and may involve only one type of information, for example, just access logs from Firewall/Gateway 710 or just activity logs from Web Server 715 . Logging information may be encrypted for transport across Secure Connection 725 and may be further encrypted for storage at Log Repository 735 as described in more detail below. Logging information is also preferably compressed before being encrypted. Logging information is typically highly compressible, resulting in savings in transmission bandwidth.
The transmission of information from Firewall/Gateway 710 , Web Server 715 and/or Mail Server 720 to Log Repository 735 may be immediate or periodic. For example, information may be compressed hourly or daily and transmitted to Log Repository 735 . In a preferred embodiment, there is no local permanent storage of log information by Firewall/Gateway 710 , Web Server 715 or Mail Server 720 , or alternatively any permanent storage of such data is periodically deleted. The strict adherence to this policy allows the entity operating the log generating computers to establish that all of the information associated with access or activity is stored in Log Repository 735 . In other embodiments, this is not critical and the log generating computers may store the logs locally in addition to transmitting them to Log Repository 735 .
FIG. 7B illustrates access to Log Repository 755 by Data Access Client 740 across Secure Connection 745 . In some embodiments, Account Data 760 , which records information such as MAC Address Registration information or other information associated with users or accounts, is stored along with Log Repository 755 . In certain embodiments of the present invention, Log Repository 755 and Account Data 760 are stored across Jurisdictional Boundary 750 from the machines that access the information. Data Access Client 740 and the communication between Data Access Client 740 and Log Repository 755 and Account Data 760 are carefully designed to satisfy the needs of the entities involved. In some cases, Log Repository 755 stores raw log information but Data Access Client only has access to summary information. In other cases, logged information may be summarized before it is stored in Log Repository 755 . In still other cases, logged information may be maintained in complete form for a certain period of time, and then summarized for further storage for a second period of time. The method of accessing Log Repository 755 by Data Access Client 740 can also be designed such that after a certain period of time, information is no longer available. This feature removes the burden from the log generating entity to delete previously stored information. This means that in cases where information is requested (e.g. via subpoena) that is outside the bounds of the access policy that has been specifically provided to Data Access Client 740 , it becomes trivial for the log generating entity to prove that it has no responsive documents. Thus, by carefully designing the data access policy, an entity generating log information can achieve an optimal and most cost effective balance between having access to information needed for business purposes and complying with all applicable laws.
In order to provide for the protection of information stored in a remote log repository, a variety of flexible encryption options are possible. FIG. 8A illustrates an encryption scenario in which Key Manger 825 generates a matched Encode Key 815 and Decode Key 830 , using techniques such as are well known in the field of public key cryptography. Server 805 generates logging information, encoding of that information takes place in Box 810 , and the encoded information is stored in Repository 820 . The encoding process 810 can take place at Server 805 , at Repository 820 , or at an intermediary machine (not shown). During data access, the encoded log information is decoded by Box 835 using Decode Key 830 and delivered to Reporting system 840 , such as the Data Access Client 740 described in connection with FIG. 7B . The data decoding process 835 can be performed at Repository 820 , at Reporting system 840 , or at an intermediary machine (not shown). The Key Manager 825 may be operated by the entity or entities generating the logs, by the entity or entities having access to the logs (if different), or by another entity, such as a third party or a government agency. The encoding and decoding illustrated in FIG. 8A may be employed on top of encryption mechanisms utilized to transmit the information securely between the Server 805 and Repository 820 and between Repository 820 and Reporting System 840 .
An alternative embodiment of encoding and decoding of logging information is illustrated in FIG. 8B . Server 855 , Repository 870 and Reporting system 895 are operated in substantially the same way as Server 805 , Repository 820 and Reporting system 840 described above in connection with FIG. 8A . FIG. 8B utilizes two key managers, Key Manager 850 and Key Manager 890 for generating pairs of encode and decode keys. Key Manager 850 generates encode key 864 and decode key 886 and Key Manager 890 generates encode key 866 and decode key 884 . Log information from Server 855 is encoded with both encode keys, first with encode key 864 at box 860 and then with encode key 866 at box 862 . The encoding processes 860 and 862 can take place at Server 855 , at Repository 820 , or at an intermediary machine (not shown). Additionally, encoding process 860 may take place in one location and encoding process 862 may take place at a different location.
During data access, the encoded log information is decoded first at box 880 using decode key 884 , then at box 882 using decode key 886 and then delivered to Reporting system 895 . The data decoding processes 880 and 882 can be performed at Repository 870 , at Reporting system 895 , or at an intermediary machine (not shown). Additionally decoding process 880 may take place at one location and decoding process 882 may take place at a different location. Key Managers 850 and 890 may be operated by the entity or entities generating the logs, by the entity or entities having access to the logs (if different), or by another entity, such as a third party or a government agency. Additionally, different entities may operate Key Manager 850 and 890 . For example, Key Manager 850 may be co-located with Server 855 and Key Manager 890 may be co-located with Reporting system 895 . In the case that encode key 866 and decode key 886 are considered “public” keys and encode key 864 and decode key 884 are considered “private” keys, then the embodiment of FIG. 8B accomplishes both authentication and encryption of log information stored in Repository 870 . The embodiment of FIG. 8B allows information to be protected even when multiple entities are involved in the generation, maintenance and utilization of the information. Those of skill in the art will appreciate that there are many alternative schemes for encrypting and authenticating the data that is stored the remote repository.
In one embodiment of the present invention, encode/decode key pairs 815 / 830 , 864 / 886 and 866 / 884 are designed to be newly generated periodically. For example Key Manager 825 , 850 and 890 could generate new key pairs every day and distribute them as appropriate. This would allow information to be easily made inaccessible by deleting the decryption keys. For example, by destroying decryption key 884 and all copies, the information associated with that day can be effectively deleted. The same key management policy can be employed to group other information, such as according to groups of users, kinds of activity, etc. The application of a decryption key destruction policy to enforce specific data access specifications can be used in addition to or instead of a repository access policy as was described above in connection with Data Access Client 740 .
The present invention has been described above in connection with several preferred embodiments. This has been done for purposes of illustration only, and variations of the inventions will be readily apparent to those skilled in the art and also fall within the scope of the invention. | A method and apparatus for remote logging of access to and activity on a computerized network is provided. Logging information is transmitted to a remote log repository and is not maintained by the local log generating machine. After the logging information is stored in the remote repository, the access to the information is controlled by a specific policy that governs the type of information and the time period during which the information is available. No access is provided to information outside the bounds of the access policy. Preferably the remote log repository is outside the jurisdiction of relevant authorities. This allows the access policy between the log generating entity and the log repository to dictate precisely the information that is under the control of the log generating entity. The use of a remote log repository and a specific access policy affords flexibility to the log generating entity in balancing its multiple responsibilities and makes responding to subpoenas cost effective and efficient. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an active remote encryption and switching device, especially to an automotive active remote encryption and switching device that uses video mobile phones to transmit signals through wireless communication equipments for control of switches in vehicles and vehicle security.
[0003] 2. Description of Related Art
[0004] Having a car stolen is absolutely a nightmare for people who love vehicles. Thus most of cars are equipped with anti-theft devices. However, vehicles are stolen more frequently in a shorter period due to renewed attack on vehicles.
[0005] According to satellite technology and network transmission available now, a plurality of anti-theft systems such as intelligent anti-theft system, global positioning system (GPS), etc has been developed now. When a car was stolen, GPS is used to estimate the position of the stolen car so as to get the track of the car. This is quite different from conventional anti-theft alarm with a buzzer. Although the GPS system can trace the vehicle position, it informs the user passively and can't talk to the intruder, record images or remote control the vehicle.
SUMMARY OF THE INVENTION
[0006] Therefore it is a primary object of the present invention to provide an automotive active remote encryption and switching device in which remote images and information are sent back to users through wireless communication for monitoring vehicle status and controlling the vehicle. Thus users can take corresponding measures by video mobile phones that control vehicles at the remote end. Moreover, by the wireless communication function of the video mobile phone in combination with the telecommunications systems, trilateration that determines the relative position of vehicles and vehicle tracking are achieved.
[0007] In order to achieve the above object, the automotive active remote encryption and switching device consists of at least one video mobile phone with specific permission, a control mainframe for receiving signals from the video mobile phone, a remote video recorder mounted in the vehicle, a detection unit that detects conditions inside the vehicle and a receiver that receives signals from the control mainframe.
[0008] Moreover, the signal receiving interface has encryption settings and corresponds to at least one video mobile phone with permission. Thus there can be several mobile phones, each used by one family member. The video mobile phone is a wireless mobile phone that supports at least 3 rd generation (3G) of standards for mobile telecommunications and mobile phones services.
[0009] Furthermore, the detection unit can be a horizontal detector with a gyroscope, a pressure sensor, an infrared sensor, a smoke detector, etc. Different detectors are used to adapt various conditions in the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein
[0011] FIG. 1 is a schematic drawing showing structure of an embodiment according to the present invention;
[0012] FIG. 2 is a schematic drawing showing an embodiment of a detection unit according to the present invention;
[0013] FIG. 3 is a schematic drawing showing an embodiment of the present invention in use.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] Refer to FIG. 1 and FIG. 2 , an automotive active remote encryption and switching device that sends remote images and information back as well as controls on/off of at least one remote vehicle switch (A) includes at least one video mobile phone 1 , a remote video recorder 2 , a control mainframe 3 , a storage device 4 , a receiver 5 and a detection unit 6 .
[0015] The video mobile phone 1 is a specific video mobile phone 1 that supports 3G standards, and sends or receives encrypted signals by a wireless telecommunications system (B). The remote video recorder 2 is an image recording unit for video recording and monitoring conditions in vehicles. The control mainframe 3 is a remote receiver for sending or receiving the encrypted signals from the video mobile phone by the wireless telecommunications system as well as decrypting and modulating the encrypted signals received to generate audio/video signals 331 and switching signals 332 . The control mainframe 3 consists of a signal receiving interface 31 , a digital signal processor 32 , and a central processing unit 33 . The signal receiving interface 31 is a remote receiver for sending or receiving the encrypted signals from the video mobile phone 1 by the wireless telecommunications system (B). The digital signal processor 32 is a processor that decrypts and modulates the encrypted signals received by the signal receiving interface 31 . The central processing unit 33 receives images from the remote video recorder 2 and decrypted signals from the digital signal processor 32 , and then outputs audio/video signals 331 as well as switching signals 332 . The audio/video signals 331 are sent to the signal receiving interface 31 for being transmitted to the specific video mobile phone 1 and stored. As to the switching signals 332 , they are sent to the vehicle switch (A). The storage device 4 receives the audio/video signals 331 from the central processing unit 33 of the control mainframe 3 and stores the audio/video signals 331 . The receiver 5 is arranged at the vehicle switch (A) and is used for receiving the switching signals 332 from the central processing unit 33 of the control mainframe 3 so as to make the vehicle switch (A) execute the switching signals 332 . The detection unit 6 is used for detecting conditions in the vehicle and sending sensing signals to the remote video recorder 2 and to the central processing unit 33 of the control mainframe 3 so that the sensing signals together with images from the remote video recorder 2 are sent to the central processing unit 33 of the control mainframe 3 .
[0016] Refer to FIG. 2 and FIG. 3 , the control mainframe 3 disposed in the vehicle gives specific permission to the users' video mobile phone 1 and has encryption settings at the same time. One control mainframe 3 is able to correspond to at least one video mobile phone 1 with permission.
[0017] When the vehicle is parked on a road and the driver forgot to lock the door, the driver can send a command through the specific video mobile phone 1 with permission to the signal receiving interface 31 of the control mainframe 3 by wireless communication. At the same time, input a password for the encryption so as to allow the signal receiving interface 31 receiving the signal of the command. The encrypted signal received by the signal receiving interface 31 is decrypted and modulated by the digital signal processor 32 . The decrypted signal is sent to the central processing unit 33 that outputs at least one audio/video signal 331 and at least one switching signal 332 according to the decrypted signal received. The switching signal 332 is sent to the receiver 5 mounted in a central locking switch that controls the door locks. The receiver 5 executes the switching signal to turn on the central locking switch for door lock. Moreover, the communication between the video mobile phone 1 and the control mainframe 3 , and images/voices (audio/video signals 331 ) from the remote video recorder 2 to the specific mobile phone 1 are all through the wireless communication. By the storage device 4 of the video mobile phone 1 , the audio/video signals 331 are stored or are further sent to a cloud storage platform 4 of telecommunications service providers for storage. Furthermore, the video mobile phone 1 corresponding to the signal receiving interface 31 can send messages in a single time, multiple times or continuingly so as to control and operate a plurality of vehicle switches (A) in the car.
[0018] In another embodiment, when the vehicle is parked on a road and someone gets into the car by picking the lock on the car door, the detection unit 6 of the vehicle switch (A) detects signals from the surrounding environment. For example, the detection unit 6 can be a horizontal detector with a gyroscope or a vibration sensor that detects shaking of the car. The shaking represents an intrusion or unintentional contact. Or the detection unit 6 is a pressure sensor that detects pressure changes in the car due to intrusion, bump or other reasons. Or the detection unit 6 is an infrared sensor with an inducing circuit that is activated when the circuit is blocked by objects on the driver's or passenger's seat. This represents the intrusion and an anti-theft alarm is sent. Or the detection unit 6 is a smoke detector that is activated by fires caused by overheat in the car or other reasons. Different detectors are used to adapt various conditions in the vehicle. The detection unit 6 can be a single detector or a combination of several detectors. After receiving the signal, the sensing signals together with the images from the remote video recorder 2 are sent to the central processing unit 33 for decryption. The audio/video signals 331 are transmitted to user's video mobile phone 1 by the wireless telecommunications system (B). According to the audio/video signals 331 received, the user can monitor the person broken into the car and use the video mobile phone 1 to execute the instructions. The video mobile phone 1 with specific permission connects to the signal receiving interface 31 of the control mainframe 3 by the wireless communication. A password for the encryption is input at the same time so that the signal receiving interface 31 is allowed to receive the message. The encrypted signal received by the signal receiving interface 31 is decrypted and modulated by the digital signal processor 32 . Next the decrypted signal is sent to the central processing unit 33 for audio/video signal 331 output and switching signal 332 output. The switching signal 332 is sent to be received and executed by the receiver 5 of the vehicle switch (A) to lock the car door, turn off the power for door lock, or make a buzzing alarm to prevent burglars getting into the car and call the police, etc. Later the recorded images (audio/video signals 331 ) are sent to the specific video mobile phone 1 by wireless communication and are stored in the storage device 4 of the video mobile phone 1 , or are further sent to a cloud storage service 4 provided by telecommunications service providers for storage.
[0019] Compared with techniques available now, the present invention has following advantages
1. The device of the present invention sends signals and executes commands by wireless communication so that the signals can be transmitted in the place where the mobile phone can receive signals. There is no need to use wired transmission media such as wires or cables that have bandwidth problems. Thus the construction cost of the telecom systems is effectively reduced. 2. The vehicle switches for anti-theft and security mounted in the vehicle are controlled through remote wireless communication so as to protect vehicles from being stolen. 3. By the connection between the user's video mobile phone and the vehicle switches in the car (one is active and the other is passive) and wireless telecommunications that allow the signal receiving interface sending and receiving interactive signals, the commands are executed in an active way and related information is transmitted to the user actively.
[0023] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | An automotive active remote encryption and switching device is revealed. Remote images and information are transmitted through wireless communication for monitoring vehicle status. The device includes at least one video mobile phone with specific permission, a control mainframe for receiving signals from the video mobile phone, a remote video recorder mounted in a vehicle, a detection unit that detects conditions inside the vehicle and a receiver that receives signals from the control mainframe. Thereby the remote images showing conditions in the vehicle are detected by the detection unit and sent to users by wireless communication equipments available now. Thus users can carry out corresponding measures and the active remote control of the vehicle is achieved by the video mobile phone. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/855,735, which was filed Nov. 1, 2006, and which is incorporated herein by reference.
FIELD
[0002] Embodiments relate to mobile broadcasting and specifically roaming associated with mobile broadcast services and user mobility.
BACKGROUND
[0003] Broadcast roaming refers to the ability of a user to receive broadcast services from a Mobile Broadcast Service Provider different from the Home Mobile Broadcast Service Provider with which the user has a contractual relationship.
[0004] The current state of the art—OMA BCAST TS Services and OMA BCAST TS Service Guide—defines a method to signal existence of service providers, such as BCAST Subscription Managers (BSMs), which may be responsible for service provisioning such as subscription and payment related functions, the provision of information used for BCAST Service reception, and BCAST device management. The signaling may involve methods of signaling through Service Guide Announcement Sessions and Service Guide Delivery Descriptors (SGDDs) within.
[0005] However, the current state of the art specification does not disclose solutions to the following problems:
1) How does a terminal know when it is roaming? 2) Which BSM can a terminal roam to (i.e. which BSM can a terminal select so that the BSM will serve the terminal)? 3) If multiple BSMs are available to serve the terminal, which BSM is the best to use?
[0009] For example, see OMA BCAST 1.0 TS Services [Mobile Broadcast Services; Draft Version 1.0 (19 Apr. 2006); OMA-TS-BCAST_Services-V1 — 0-20060419-D] and OMA BCAST 1.0 TS Service Guide [Service Guide for Mobile Broadcast Services; Draft Version 1.0 (24 Mar. 2006); OMA-TS-BCAST_ServiceGuide-V1 — 0 — 0-20060324-D]. The following table contains a partial list and description of elements defined by Amendments to the OMA BCAST 1.0 Service Guide, and specifically, the Service Guide Delivery Descriptor.
[0000]
Name
Type
Category
Cardinality
Description
Data Type
. . .
BSMSelector
E3
NO/
0 . . . N
This is a BSM code that
TM
allows a terminal to
determine whether the
SGDU's in this SGDD
DescriptorEntry - among
the SGDU's that are
announced in various
Descriptor Entries in
various SGDD's - is
associated with the
terminal's affiliated BSM.
In case the terminal is
equipped with one or more
BSMFilterCodes, the
BSMSelector acts as an
access filter for the
SGDU's of the
DescriptorEntry and the
following applies:
Usage in home
network:
The terminal
SHALL only use
those SGDU's in
the DescriptorEntry
that have a
matching
BSMFilterCode.
If the terminal has
multiple matching
BSMFilterCodes,
the terminal MAY
select one of the
BSMSelectors with
a matching
BSMFilterCode and
SHALL then only
use the SGDU's of
DescriptorEntries
with the selected
BSMSelector, until
it selects another
BSMSelector.
If the BSMSelector
is not present the
terminal SHALL
NOT use any of the
SGDU's in the
DescriptorEntry.
Usage in roaming
network:
If the terminal has a
matching
BSMFilterCode in
any of the SGDD's
in this network, then
the terminal SHALL
only use those
SGDU's in the
DescriptorEntry.
If the terminal has
multiple matching
BSMFilterCodes,
the terminal MAY
select one of the
BSMSelectors with
a matching
BSMFilterCode and
SHALL then only
use the SGDU's of
DescriptorEntries
with the selected
BSMSelector, until
it selects another
BSMSelector.
If the terminal or
smartcard does not
have a matching
BSMFilterCode in
any of the SGDD's
in this network, the
terminal MAY
select any
BSMSelector and
SHALL only use
the SGDU's of
DescriptorEntries
with the selected
BSMSelector, until
it selects another
BSMSelector.
If the BSMSelector
is not present, the
terminal can use all
SGDU's in the
DescriptorEntry.
In case the terminal is not
equipped with a
BSMFilterCode, the
following applies:
Usage in home
network:
The terminal MAY
select any
BSMSelector that
does not contain a
BSMFilterCode,
and SHALL then
only use the
SGDU's of
DescriptorEntries
with the selected
BSMSelector, until
it selects another
BSMSelector.
Furthermore, the
terminal SHALL
NOT use the
SGDU's of
DescriptorEntries
that have a
BSMSelector with a
BSMFilterCode.
If the BSMSelector
is not present in any
of the SGDD's the
terminal can use all
SGDU's in the
DescriptorEntry.
Usage in roaming
network:
The terminal MAY
select any
BSMSelector and
SHALL then only
use the SGDU's of
DescriptorEntries
with the selected
BSMSelector, until
it selects another
BSMSelector.
If the BSMSelector
is not present in any
of the SGDD's the
terminal can use all
SGDU's in the
DescriptorEntry.
BSMSelector contains the
following attribute:
id
BSMSelector contains the
following elements:
BSMFilterCode
name
id
A
NM/TM
1
Identifier of the
AnyURI
BSMSelector, unique
within the network
BSMFilterCode
E4
NO/TM
0 . . . 1
The code that specifies this
String
BSMSelector.
Contains the following
attribute:
type
type
A
NM/
1
The type of
unsignedByte
TM
BSMFilterCode.
1 - BSMCode (Smart Card
Code)
This is used if the
determination is made
based on the country and
operator code in the
(U)SIM/(R-)UIM/CSIM
2 - BSMCode (Non Smart
Card Code):
This is used if the
determination is made
based on the country and
operator code in the
terminal
Other values are reserved.
name
E4
NM/TM
1 . . . N
Provides a user readable
String
name for the BSMSelector,
possibly in multiple
languages.
The language is expressed
using built-in XML
attribute xml:lang with this
element . . .
This attribute can be used
to provide information to
the user so he can select the
BSMSelector the terminal
has to use.
BRIEF SUMMARY
[0010] The following presents a simplified summary in order to provide a basic understanding of some aspects of the invention. The summary is not an extensive overview of the invention. It is neither intended to identify key or critical elements of the invention nor to delineate the scope of the invention. The following summary merely presents some concepts of the invention in a simplified form as a prelude to the more detailed description below.
[0011] Embodiments are directed to broadcast roaming, i.e., providing service/content to a terminal from a visited service provider. An embodiment is directed to sending a roaming rule request to a service provider, receiving a roaming rule response from the service provider, acquiring service guide fragments from the service provider and processing the service guide fragments in accordance with the received roaming rule response, sending to a selected service provider a service provisioning request for a purchase item, receiving from the selected service provider a service provisioning response regarding the purchase item, and accessing service and/or content related to the purchase item, wherein the service and/or content is provided by the visited service provider. Embodiments are directed to exchanging between a visiting service provider and a home service provider of the terminal a roaming authorization request regarding a purchase item and a roaming authorization response regarding the purchase item.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Other objects and features will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims only. It should be further understood that the drawings are merely intended to conceptually illustrate the structures and procedures described herein.
[0013] FIG. 1 is a block diagram illustrating a computing device, in accordance with aspects of the present invention;
[0014] FIG. 2 is a component diagram illustrating a terminal provisioning system, in accordance with aspects of the present invention;
[0015] FIG. 3 is a block diagram showing an illustrative protocol stack used for message exchange, in accordance with aspects of the present invention;
[0016] FIG. 4 is a diagram illustrating a broadcast roaming technique, in accordance with certain aspects of the present invention.
DETAILED DESCRIPTION
[0017] In the following description of the various embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration various embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope and spirit of the present invention.
[0018] An aspect of the invention relates to signaling the query address for each broadcast subscription management (BSM) declared in the BSM. This can be done by adding an element “RoamingQueryAddress” to the SGDD under the element “BSMSelector”. Another aspect of the invention relates to determining whether a terminal is roaming. Yet another aspect of the invention specifies the content of a roaming query message and respective answer message. Still another aspect of the invention discloses a method to determine which of the declared BSM(s) is/are best suited to serve a terminal while it is roaming.
[0019] Various abbreviations used herein are provided below.
[0020] BDS—Broadcast Distribution System
[0021] A system containing the ability to transmit the same IP flow to multiple Terminal devices simultaneously. A Broadcast Distribution System typically uses techniques that achieve efficient use of radio resources.
[0022] BDS SD—Broadcast Distribution System Service Distribution
[0023] Responsible for the coordination and delivery of broadcast services to the BDS for delivery to the terminal, including file and streaming distribution, and Service Guide distribution.
[0024] BSDA and BSD/A—BCAST Service Distribution and AdaptationResponsible for the aggregation and delivery of BCAST Services, and performs the adaptation of the BCAST Enabler to underlying Broadcast Distribution Systems.
[0025] BSA—BCAST Service Application
[0026] Represents the service application of the BCAST Service, such as streaming audio/video or movie download.
[0027] IN—Interaction Network
[0028] A system containing the ability to transmit, for example IP flow, SMS, MMS, through Interaction Channel to a Terminal device and transmitting user's responses through Interaction Channel to a BCAST Service Application. A system containing the ability to transmit IP flow through Interaction Channel to a Terminal device.
[0029] BSM—BCAST Subscription Management
[0030] Responsible for service provisioning such as subscription and payment related functions, the provision of information used for BCAST Service reception, and BCAST device management.
[0031] SGDD Service Guide Delivery Descriptor
[0032] SGDU Service Guide Delivery Unit
[0033] FIG. 1 illustrates a block diagram of a generic terminal device 101 that may be used according to an illustrative embodiment of the invention. Device 101 may have a processor 103 for controlling overall operation of the terminal device and its associated components, including RAM 105 , ROM 107 , input/output module 109 , and memory 115 .
[0034] I/O 109 may include a microphone, keypad, touch screen, and/or stylus through which a user of device 101 may provide input, and may also include one or more of a speaker for providing audio output and a video display device for providing textual, audiovisual and/or graphical output.
[0035] Memory 115 may store software used by device 101 , such as an operating system 117 , application programs 119 , and associated data 121 . For example, one application program 121 used by device 101 according to an illustrative embodiment of the invention may include computer executable instructions for invoking user functionality related to communication, such as email, short message service (SMS), and voice input and speech recognition applications.
[0036] Device 101 may also be a mobile terminal including various other components, such as a battery, speaker, and antennas (not shown). I/O 109 may include a user interface including such physical components as a voice interface, one or more arrow keys, joy-stick, data glove, mouse, roller ball, touch screen, or the like. In this example, the memory 115 of mobile device 101 may be implemented with any combination of read only memory modules or random access memory modules, optionally including both volatile and nonvolatile memory and optionally being detachable. Software may be stored within memory 115 and/or storage to provide instructions to processor 103 for enabling mobile terminal 101 to perform various functions. Alternatively, some or all of mobile terminal 101 computer executable instructions may be embodied in hardware or firmware (not shown).
[0037] Additionally, a mobile terminal 101 may be configured to send and receive transmissions through various device components, such as an FM/AM radio receiver, wireless local area network (WLAN) transceiver, and telecommunications transceiver (not shown). In one aspect of the invention, mobile terminal 101 may receive radio data stream (RDS) messages. Mobile terminal 101 may be equipped with other receivers/transceivers, e.g., one or more of a Digital Audio Broadcasting (DAB) receiver, a Digital Video Broadcasting (DVB) receiver, a Digital Radio Mondiale (DRM) receiver, a Forward Link Only (FLO) receiver, a Digital Multimedia Broadcasting (DMB) receiver, etc. Hardware may be combined to provide a single receiver that receives and interprets multiple formats and transmission standards, as desired. That is, each receiver in a mobile terminal 101 may share parts or subassemblies with one or more other receivers in the mobile terminal device, or each receiver may be an independent subassembly.
[0038] The invention is described through three separate solutions. Any combination of these solutions is also possible. One common starting assumption is a situation where a terminal acquires Service Guide Delivery Descriptors (SGDDs). The SGDDs are enhanced according to an aspect of this invention so that the subelement BSMSelector of the SGDD contains subelement RoamingQueryAddress. A fully modified BSMSelector according to this invention is presented in the end of this section.
[0039] Solution 1—Request/Reply Solution Addressing the Case of Terminal Not Having “home” BSM.
[0040] Addressing problem (1): Since the terminal does not have any “home” BSM, i.e. no BSMFilterCodes, there is no way of telling when the terminal is roaming merely by receiving the SGDDs. In that case, it can be assumed that the terminal is always roaming. However, the following statement in the prior art is flawed: “If the terminal or smartcard does not have a matching BSMFilterCode in any of the SGDD's in this network, the terminal MAY select any BSMSelector and might only use the SGDU's of DescriptorEntries with the selected BSMSelector, until it selects another BSMSelector.”
[0041] In a realistic operational setting this rarely is true, since it ignores the roaming agreements between operators (i.e. BSMs). Thus, problems (2) and (3) remain.
[0042] Addressing problem (2) and (3):
1. A terminal acquires SGDDs (either receiving over broadcast Service Guide Announcement Channel or by retrieving those otherwise). 2. From the acquired SGDDs the terminal compiles a set of pairs of {BSMFilterCode, RoamingQueryAddress}. 3. For each BSMFilterCode, the terminal sends RoamingQueryRequest to the RoamingQueryAddress associated with the BSMFilterCode. One way to do this is to send all the requests simultaneously (i.e. without waiting for responses). Another way is to send the responses in priority order, one by one, first request then response, then next request, etc. Such priority order may be according to prior experience (e.g., the terminal sends requests to such BSMFilterCodes first that have been responding positively before.). Further, irrespective which way to send requests, the terminal sets a time-out timer for the requests. 4. After receiving RoamingQueryAnswers from BSMs, or, upon timeout of request message timer set in step 3, the terminal starts to analyze the received answers. 5. The terminal analyzes the received RoamingQueryAnswers especially comparing the Rule elements in the answers (A) among the answers; or (B) against the set of services, content, programs the terminal is currently receiving; or (C) against the list of service, content or programs that are in the “favorites” list of the terminal; or (D) against a specific time period terminal wishes to access services; or (E) against some other criteria such as selecting BSMs that offer the most fragments, cheapest service or where the fragment/cost ratio is best. Any combination of (A) to (E) is also naturally possible. For items (B) and (C), the comparison can be based on FragmentIDs or GlobalServiceID since these identifiers are the common element in the Rules and in the Service Guides, i.e. a Rule that is defined in terms of FragmentID can be mapped to Service Guide. 6. Based on analysis, a terminal determines which BSM(s) it will use while roaming. 7. After selection, based on Rules, the terminal may refresh the Service Guide view as displayed to the user. The terminal may filter out/gray elements that are not available and may show the selected BSM id in the screen or in the menu. Alternately the terminal can list the available successfully resolved BSMs under a pull down menu where the key is either BSMid or any of the criteria (A)-(E) listed in step 5.
[0050] The following provides more detailed information related to some of the concepts introduced above.
[0051] RoamingQueryRequest is a message logically containing the following information:
[0052] Optional terminal ID
[0053] Optional home “BSM” identification (one, some or all of terminals BSMFilterCodes and their types such aif they are smart card codes or not)
[0054] Optional list of Service Guide fragment ids or GlobalServiceIds, or GlobalContentIds that terminal wants to access on while roaming.
[0055] RoamingQueryResponse is a message logically containing the following information:
[0056] Answering BSMid as BSMFilterCode
[0057] Optional response code for faster terminal processing:
ALL ALLOWED—meaning: no restrictions while roaming NOT ALLOWED—meaning: roaming not possible ALLOWED WITH RULES—meaning: see the rules of the payload
[0061] Optional Rules is a combination of one or several of the following:
ALLOW FRAGMENT ID<list of fragment ids> ALLOW GLOBAL SERVICE ID<list of global service ids> ALLOW GLOBAL CONTENT ID<list of global content ids> DENY FRAGMENT ID<list of fragment ids> DENY GLOBAL SERVICE ID<list of global service ids> DENY GLOBAL CONTENT ID<list of global content ids> ALLOW TIME PERIOD<start time UTC><end time UTC> DENY TIME PERIOD<start time UTC><end time UTC> COST INFORMATION for any of the above rules
[0071] RoamingQueryRequest and RoamingQueryResponse can be instatiated as binary structure, XML or any other known message type. The protocol to convey RoamingQueryRequest and RoamingQueryResponse can be any data network protocol—for example UDP, TCP, HTPP, SOAP.
[0072] Solution 2—Request/Reply solution addressing the case of the terminal having a “home” BSM. This solution is almost identical to the Solution 1. The only difference in the start conditions is that the terminal has a “home” BSM(s), i.e. it has one or more BSMFilterCodes.
[0073] Addressing problem (1): Since the terminal has one or more “home” BSMs, i.e. no BSMFilterCodes, there is a way of telling when the terminal is roaming just by receiving the SGDDs. The terminal simply compares its BSMFilterCodes to the ones present in the SGDDs. If any of the terminal's BSMFilterCodes are present in SGDD, the terminal is not roaming. Otherwise the terminal is roaming. For the roaming case, problems (2) and (3) may still remain. Those problems can be solved in an identical manner to Solution 1.
[0074] Solution 3—Device Management/Terminal Provisioning Based Solution. In this solution the terminal is provisioned—using a terminal provisioning function such as OMA Device Management—with roaming related information such as terminal's own BSMFilterCodes and other BSMFilterCodes together with associated Rules and possibly RoamingQueryAddresses to each BSMFilterCode. One or more, or even all entries of type {BSMFilterCode, Rule, RoamingQueryAddress} can be instantiated within a single Management Object.
[0075] Referring now to FIG. 2 , a diagram is shown illustrating such a solution, in which roaming information is instantiated as OMA DM Management Objects and the Management Objects are delivered and provisioned to a terminal with OMA DM methods. This means that on the terminal, the Management Objects carrying the roaming information are “installed” into the management tree of the terminal. A roaming function, service guide function or any other function within the terminal can then access the roaming information using the methods defined for accessing the management object tree. FIG. 2 illustrates an end-to-end view of such a technique.
[0076] Below is a modified Service Guide Delivery Descriptor illustrated partially according to certain aspects of this invention.
[0000]
Name
Type
Category
Cardinality
Description
Data Type
. . .
BSMSelector
E3
NO/
0 . . . N
This is a BSM code that
TM
allows a terminal to determine
whether the SGDU's in this
SGDD DescriptorEntry -
among the SGDU's that are
announced in various
DescriptorEntries in various
SGDD's - is associated with
the terminal's affiliated BSM,
In case the terminal is
equipped with one or more
BSMFilterCodes, the
BSMSelector acts as an access
filter for the SGDU's of the
DescriptorEntry and the
following applies:
Usage in home
network:
The terminal might
only use those
SGDU's in the
DescriptorEntry that
have a matching
BSMFilterCode.
If the terminal has
multiple matching
BSMFilterCodes, the
terminal MAY select
one of the
BSMSelectors with a
matching
BSMFilterCode and
might then only use
the SGDU's of
DescriptorEntries with
the selected
BSMSelector, until it
selects another
BSMSelector.
If the BSMSelector is
not present the
terminal might not use
any of the SGDU's in
the DescriptorEntry.
Usage in roaming
network:
If the terminal has a
matching
BSMFilterCode in any
of the SGDD's in this
network, then the
terminal might only
use those SGDU's in
the DescriptorEntry.
If the terminal has
multiple matching
BSMFilterCodes, the
terminal may select
one of the
BSMSelectors with a
matching
BSMFilterCode and
might then only use
the SGDU's of
DescriptorEntries with
the selected
BSMSelector, until it
selects another
BSMSelector.
If the terminal or
smartcard does not
have a matching
BSMFilterCode in any
of the SGDD's in this
network, the terminal
may select any
BSMSelector and
might only use the
SGDU's of
DescriptorEntries with
the selected
BSMSelector, until it
selects another
BSMSelector.
If the BSMSelector is
not present, the
terminal can use all
SGDU's in the
DescriptorEntry.
In case the terminal is not
equipped with a
BSMFilterCode, the following
applies:
Usage in home
network:
The terminal may
select any
BSMSelector that does
not contain a
BSMFilterCode, and
might then only use
the SGDU's of
DescriptorEntries with
the selected
BSMSelector, until it
selects another
BSMSelector.
Furthermore, the
terminal might not use
the SGDU's of
DescriptorEntries that
have a BSMSelector
with a
BSMFilterCode.
If the BSMSelector is
not present in any of
the SGDD's the
terminal can use all
SGDU's in the
DescriptorEntry.
Usage in roaming
network:
The terminal may
select any
BSMSelector and
might then only use
the SGDU's of
DescriptorEntries with
the selected
BSMSelector, until it
selects another
BSMSelector.
If the BSMSelector is
not present in any of
the SGDD's the
terminal can use all
SGDU's in the
DescriptorEntry.
BSMSelector contains the
following attributes:
id
RoamingQueryAddress
BSMSelector contains the
following elements:
BSMFilterCode
name
id
A
NM/TM
1
Identifier of the BSMSelector,
AnyURI
unique within the network
BSMFilterCode
E4
NO/TM
0 . . . 1
The code that specifies this
String
BSMSelector.
Contains the following
attribute:
type
type
A
NM/
1
The type of BSMFilterCode.
unsignedByte
TM
1 - BSMCode (Smart Card
Code)
This is used if the
determination is made based
on the country and operator
code in the (U)SIM/(R-)
UIM/CSIM
2 - BSMCode (Non Smart
Card Code):
This is used if the
determination is made based
on the country and operator
code in the terminal
Other values are reserved.
Name
E4
NM/TM
1 . . . N
Provides a user readable name
String
for the BSMSelector, possibly
in multiple languages.
The language is expressed
using built-in XML attribute
xml:lang with this element . . .
This attribute can be used to
provide information to the
user so he can select the
BSMSelector the terminal has
to use.
RoamingQueryAddress
A
NM/TM
1 . . . N
Address to which the terminal
anyURI
MAY send the
RoamingQueryRequest
[0077] Broadcast Roaming allows a user to receive Broadcast Services from a Broadcast Service Provider different from his Home Broadcast Service Provider. The following main scenario can be provided for Broadcast Roaming. At any point of time the user may want to access the Broadcast Services from a Visited Mobile Service Provider. There are many possible reasons for this. For example, the user may not be able to access the services provided by the Home Mobile Broadcast Service Provider. In this case, Broadcast Roaming allows the user to receive Broadcast Services from another Broadcast Service Provider independent of the underlying Broadcast Distribution System.
[0078] The Mobile Broadcast Services (BCAST) 1.0 Enabler enables Broadcast Roaming through the use of a Service Guide, through roaming signaling between Terminal and Visited Mobile Broadcast Service Provider, through roaming signaling between Visited Mobile Broadcast Service Provider and Home Mobile Broadcast Service Provider and through the Terminal Provisioning function. The following gives an overview of the components:
[0079] Service Guide Delivery Descriptors (SGDD) within the Service Guide declare the existence of and availability of Service Guide fragments. The SGDD allows one to declare which fragments are associated with which Mobile Broadcast Service Provider (through use of BSMFilterCodes). Related to this signaling, there are also filtering rules in the Service Guide specification that the terminals are expected to comply with. Further, SGDD enables a method to convey points of contact which the visiting terminals can contact in case Broadcast Roaming is needed. This aspect of Broadcast Roaming is normatively specified within the specification of SGDD in [BCAST10-ServiceGuide].
[0080] Terminal Provisioning enables the Home Broadcast Service Provider to maintain terminal-resident elements used by the roaming function. These elements include the list of Service Providers (their BSMFilterCodes) affiliated with the terminal as well as entry details of default roaming contact point—the server that terminal can send roaming requests in the case terminal does not find any other entry points within the Service Guide signaling. Finally, these elements include parameters that can be used to control terminal behavior: an element that controls whether roaming requests should always be sent to a Home BSM and an element that determines terminal behavior for fragments that are not associated with any BSMSelector. [These aspects of Broadcast Roaming are normatively specified within OMA-TS-BCAST_Services-V1 — 0-20060419-D, Appendix E (Management Object)].
[0081] Roaming request and response messages between a terminal and BSM associated with Home and/or Visited Mobile Broadcast Service Provider allow terminals to request and Broadcast Service Providers to provide the rules related to roaming. Further, these messages allow a terminal to request access to purchase items while roaming. [This aspect of Broadcast Roaming is normatively specified within OMA-TS-BCAST_Services-V1 — 0-20060419-D (section 5.8.1)]. The contact points for the request messages are signaled within the SGDDs—that aspect of Broadcast Roaming is normatively specified within the specification of SGDD in [OMA-TS-BCAST_ServiceGuide-V1 — 0 — 0-20060324-D]
[0082] The roaming messages between Home and Visited Mobile Broadcast Service Providers allow the either the Home or Visited Mobile Broadcast Service Provider to initiate the roaming as a reaction to initial user roaming request. [This aspect of Broadcast Roaming is normatively specified within OMA-TS-BCAST_Services-V1 — 0-20060419-D (section 5.8.2)].
[0083] The informative walk-through of Broadcast Roaming is described below.
[0084] Roaming messages between Terminal and BSM
[0085] The terminal uses a RoamingRuleRequest to request the RoamingRules associated with BSMSelector (identified by the id of the selector). As a response, the Terminal receives RoamingRuleResponse that carry the RoamingRules.
[0086] RoamingRuleRequest
[0000]
Name
Type
Category
Cardinality
Description
Data Type
RoamingRuleRequest
E
UserID
E1
M
1
A unique ID that
String
may be used to
identify the terminal
in both the Home
Service Provider
and Visited Service
Provider BCAST
service area. An
example is the
3GPP IMSI
(International
Mobile Subscriber
Identity).
HomeBSMFilterCode
E1
M
1
The code that
String
specifies the Home
BSM.
Contains the
following attribute:
type
type
A
M
1
The type of
unsignedByte
BSMFilterCode.
1 - BSMCode
(Smart Card Code)
This is used if the
determination is
made based on the
country and
operator code in the
(U)SIM/(R-)
UIM/CSIM
2 - BSMCode (Non
Smart Card Code):
This is used if the
determination is
made based on the
country and
operator code in the
terminal
Other values are
reserved.
BSMSelectorId
E1
M
1 . . . N
The identifier of
anyURI
BSMSelector
terminal is
requesting
RoamingRules for.
[0087] RoamingRuleResponse
[0000]
Data
Name
Type
Category
Cardinality
Description
Type
RoamingRuleResponse
E
ResponseEntry
E1
M
1 . . . N
Entry containing response
to each requested
BSMSelectorId
BSMSelectorId
E2
M
1
The identifier of
anyURI
BSMSelector for which
terminal requested
RoamingRules for and
which this ResponseEntry
is about.
RoamingRule
E2
M
1 . . . N
Entry specifying the
See
RoamingRule associated
Section
with BSMSelector.
5.8.2.3
Exclusive
E2
O
0 . . . N
Indicates whether the rules
Boolean
are exclusive. If “TRUE”,
the rules are exclusive and
terminal that accesses
fragments covered by
these rules (i.e. associated
with the BSMSelectorId)
might not access
fragments associated with
any other BSMSelectorId.
[0088] 5.8.1.3 Definition of Element RoamingRule
[0000]
Data
Name
Type
Category
Cardinality
Description
Type
RoamingRule
E
M
1
TimeFrame
E1
O
0 . . . N
Rule that defines the time frame(s)
this RoamingRule is applies to.
StartTime
E2
O
0 . . . 1
Start of the time frame. If not
int
given, the time frame is assumed to
(32 bit)
have started at some time in the
expressed
past
as
NTP
time
EndTime
E2
O
0 . . . 1
End of the time frame. If not given,
int
the time frame is assumed to end at
(32 bit)
some time in the future.
expressed
as
NTP
time
Allow
E1
O
0 . . . N
Rule that allows the Terminal to
PurchaseItemId
use the listed PurchaseItems.
PurchaseItemId
E2
M
1 . . . N
PurchaseItemID that is allowed to
anyURI
be interpreted, rendered and
accessed.
Allow
E1
O
0 . . . N
Rule that allows the Terminal to
Service
use the fragments corresponding to
listed GlobalServiceIDs.
GlobalServiceID
E2
M
1 . . . N
Fragments associated with this
anyURI
GlobalServiceID are allowed to be
interpreted, rendered and accessed.
Allow
E1
O
0 . . . N
Rule that allows the Terminal to
Content
use the fragments corresponding to
listed ContentIDs.
GlobalContentID
E2
M
1 . . . N
Fragments associated with this
anyURI
GlobalContentID are allowed to be
interpreted, rendered and accessed.
Deny
E1
O
0 . . . N
Rule that denies the Terminal to use
PurchaseItemId
the listed PurchaseItems.
PurchaseItemId
E2
M
1 . . . N
PurchaseItemID that is denied to be
anyURI
interpreted, rendered and accessed . . .
Deny
E1
O
0 . . . N
Rule that denies the Terminal to use
Service
the fragments corresponding to
listed GlobalServiceIDs.
GlobalServiceID
E2
M
1 . . . N
Fragments associated with this
anyURI
GlobalServiceID are denied to be
interpreted, rendered and accessed.
Deny
E1
O
0 . . . N
Rule that denies the Terminal to use
Content
the fragments corresponding to
listed ContentIDs.
GlobalContentID
E2
M
1 . . . N
Fragments associated with this
anyURI
GlobalContentID are denied to be
interpreted, rendered and accessed.
[0089] Roaming messages between Home BSM and Visited BSM
[0090] In case the user selects to purchase or subscribe to a PurchaseItem that is associated with a BSM that is not one of the Home BSMs associated with the terminal, the terminal sends a normal Service Provisioning message. The receiving system determines from the requested PurchaseItemId and included UserID whether the request is about roaming. Two cases for this exist: either the Terminal sends the Service Provisioing message to its Home BSM or to the Visited BSM.
[0091] In the former case, the Home BSM detects that one of its terminals is requesting a PurchaseItem served by another BSM. If the Home BSM wants to allow terminal to access the PurchaseItem, the Home BSM goes ahead and sends RoamingAuthorizationRequest to the Visited BSM. The Visited BSM answers with RoamingAuthorizationResponse.
[0092] In the latter case, the Visited BSM detects that a terminal that is not one of the terminals affiliated with this BSM is requesting a PurchaseItem served by this BSM. The Visited BSM consequently sends RoamingAuthorizationRequest to the Home BSM of the Terminal. The Home BSM answers with RoamingAuthorizationResponse.
[0093] Protocol stack for message exchanges between BSMs
[0094] Referring now to FIG. 3 , an illustrative protocol stack is shown that may be used for message exchange between BSMs. In this example, HTTP over TCP/IP may be used for the delivery of the roaming procedure authorization messages. IPsec may be used in conjunction with TCP/IP to provide secure delivery of the authorization messages.
[0095] RoamingAuthorizationRequest
[0000]
Data
Name
Type
Category
Cardinality
Description
Type
RoamingAuthorizationRequest
E
UserID
E1
M
1
A unique ID that may be used to
String
identify the terminal in both the
Home Service Provider and Visited
Service Provider BCAST service
area. An example is the 3GPP IMSI
(International Mobile Subscriber
Identity).
HomeBSMFilterCode
E1
M
1
The code that specifies the Home
String
BSM.
Contains the following attribute:
type
type
A
M
1
The type of BSMFilterCode.
unsignedByte
1 - BSMCode (Smart Card Code)
This is used if the determination is
made based on the country and
operator code in the (U)SIM/(R-)
UIM/CSIM
2 - BSMCode (Non Smart Card
Code):
This is used if the determination is
made based on the country and
operator code in the terminal
Other values are reserved.
VisitedBSMFilterCode
E1
M
1
The code that specifies the Visited
String
BSM.
Contains the following attribute:
type
type
A
M
1
The type of BSMFilterCode.
unsignedByte
1 - BSMCode (Smart Card Code)
This is used if the determination is
made based on the country and
operator code in the (U)SIM/(R-)
UIM/CSIM
2 - BSMCode (Non Smart Card
Code):
This is used if the determination is
made based on the country and
operator code in the terminal
Other values are reserved.
TerminalSubscriptionType
E1
M
1
A field that may indicate the
anyURI
subscription scope of the terminal in
terms of roaming. The Home Service
Provider and the Visited Service
Provider have a common
understanding of the field according
to roaming agreements between
them.
This element is not further specified
in this specification.
PurchaseItemID
E1
M
1 . . . N
Set of PurchaseItems which are
anyURI
associated with the VisitedBSM and
which the terminal wants to
subscribe to/purchase.
[0096] RoamingAuthorizationResponse
[0000]
Data
Name
Type
Category
Cardinality
Description
Type
RoamingAuthorizationResponse
E
UserID
E1
M
1
A unique ID that may be used to
String
identify the terminal in both the
Home Service Provider and Visited
Service Provider BCAST service
area. An example is the 3GPP IMSI
(International Mobile Subscriber
Identity).
HomeBSMFilterCode
E1
M
1
The code that specifies the Home
String
BSM.
Contains the following attribute:
type
type
A
M
1
The type of BSMFilterCode.
unsignedByte
1 - BSMCode (Smart Card Code)
This is used if the determination is
made based on the country and
operator code in the (U)SIM/(R-)
UIM/CSIM
2 - BSMCode (Non Smart Card
Code):
This is used if the determination is
made based on the country and
operator code in the terminal
Other values are reserved.
VisitedBSMFilterCode
E1
M
1
The code that specifies the Visited
String
BSM.
Contains the following attribute:
type
type
A
M
1
The type of BSMFilterCode.
unsignedByte
1 - BSMCode (Smart Card Code)
This is used if the determination is
made based on the country and
operator code in the (U)SIM/(R-)
UIM/CSIM
2 - BSMCode (Non Smart Card
Code):
This is used if the determination is
made based on the country and
operator code in the terminal
Other values are reserved.
PurchaseItemID
E1
M
1 . . . N
Set of PurchaseItems which are
anyURI
associated with the VisitedBSM and
which the terminal wants to
subscribe to/purchase.
RoamingAuthorisationStatus
E2
M
1
A field that may indicate whether the
UnsignedByte
roaming terminal has been
authorised for requested
PurchaseItem or not.
Note: The codes in table 1 are be
used
[0097] Referring now to FIG. 4 , an illustrative walk-through of a broadcast roaming technique is shown, the steps of which are described below in greater detail. Specifically, this example illustrates how broadcast roaming may achieved through the use of core functionalities of BCAST 1.0. This informative explanation of broadcast roaming is presented as a walk-through mainly from the terminal point of view.
1. The terminal scans or otherwise detects an available Broadcast Distribution Systems (BDS). 2. The terminal attempts to perform a service discovery bootstrap to locate an entry point to BCAST Service Guide on all or any of the detected BDSes. Upon successful completion of a bootstrap procedure, the terminal acquires the entry point to BCAST Service Guide over the respective bearer. Consequently, the terminal acquires SGDDs either by receiving or by retrieving those. 3. In case the terminal fails to perform a bootstrap and to locate the entry point to BCAST Service Guide over all the detected BDSes, the terminal attempts to retrieve SGDDs using the entry point as provisioned in the Terminal (defined by Management Object “<X>/SGServerAddress”). 4. Once the terminal acquires SGDDs, the terminal looks for BSMSelector elements and BSMFilterCodes within those elements in the SGDD. Together with that information and the terminal's affiliated BSM(s) which are represented within the Terminal as Management Objects with identifier ‘<X>/BSMFilterCode’, the Terminal categorizes all the fragments declared in the SGDD into three categories:
i. Fragments that are associated with a BSMFilterCode (within BSMSelector), which match at least one of the BSMFilterCodes associated with the terminal. The terminal can use, interpret and render the information contained in these fragments without restrictions. ii. Fragments that are associated with a BSMFilterCode (within BSMSelector), which does not match with any of the BSMFilterCodes associated with the terminal. The terminal can render, interpret and handle the fragments according to RoamingRules associated with this BSMSelector. BSMSelector and the associated RoamingRules are identified by the attribute “Id” present within the BSMSelector as well as in RoamingRules. iii. Fragments that are not associated with any BSMFilterCode (no BSMSelector).
In case a terminal has no Management Objects with identifier ‘<X>/BSMFilterCode’ present, the terminal can use, interpret and render the information contained in these fragments without restrictions. In case the terminal has at least one Management Object with identifier ‘<X>/BSMFilterCode’ present, the terminal will determine behavior according to Management Objects with identifier ‘<X>/IgnoreUnIdentifiedBSM’. If the Management Objects with identifier ‘<X>/IgnoreUnIdentifiedBSM’ is set with value “TRUE” the terminal cannot use, interpret and render the information contained in these fragments at all. If the Management Objects with identifier ‘<X>/IgnoreUnIdentifiedBSM’ is set with value “FALSE” the terminal can use, interpret and render the information contained in these fragments without restrictions. If the Management Objects with identifier ‘<X>/IgnoreUnIdentifiedBSM’ is not present, the terminal assumes that the value of such Management Object is “FALSE”.
5. If the terminal needs to render, interpret and handle the fragments in category (ii.) above, it acquires the RoamingRules related to the BSMSelector in question. There are three ways to achieve this.
a. The terminal fetches the RoamingRules from the Visited BSM. For that, the BSMSelector contains attribute “RoamingRuleRequestAddress” to which the terminal can address the RoamingRuleRequest. As a response of to the RoamingRuleRequest the terminal will receive RoamingRuleResponse which contains the RoamingRules associated with the BSMSelector. b. The terminal fetches the RoamingRules from the Home BSM. This happens if the BSMSelector does not have “RoamingRuleRequestAddress” present, OR, if the terminal has Management Object “<X>/ForceHomeRoamingRuleRequestAddress” present and set to “TRUE”. In these cases the terminal sends the RoamingRuleRequest to “<X>/HomeRoamingRuleRequestAddress”. As a response of to the RoamingRuleRequest the terminal will receive RoamingRuleResponse which contains the RoamingRules associated with the BSMSelector. c. The RoamingRules were originally provided as a part of BSMSelector (not illustrated in FIG. 4 ).
6. The terminal acquires Service Guide fragments. It interprets handles and renders the fragments according to RoamingRules. Consequently the terminal uses the Service Guide fragments to perform subscriptions to services and content, and to access services and content described by the Service Guide. 7. In case the user selects to purchase or subscribe to a PurchaseItem that is associated with a BSM that is not one of the Home BSMs associated with the terminal, the terminal sends a normal Service Provisioning message. The receiving system determines from the requested PurchaseItemId and included UserID whether the request is about roaming. Two cases for this exist: either the terminal sends the Service Provisioing message to its Home BSM or to the Visited BSM.
a. In the former case, the Home BSM detects that one of its terminals is requesting a PurchaseItem served by another BSM. If the Home BSM wants to allow the terminal to access the PurchaseItem, the Home BSM goes ahead and requests RoamingAuthorization from the Visited BSM. b. In the latter case, the Visited BSM detects that a terminal that is not one of the terminals affiliated with this BSM is requesting PurchaseItem served by this BSM. The Visited BSM consequently requests RoamingAuthorization from the Home BSM of the terminal. Upon successful RoamingAuthorization, the terminal is granted the right to purchase and/or subscribe to the PurchaseItem it requested.
8. The terminal accesses service and/or content related to PurchaseItem, provided by Visited Service Provider.
[0119] While illustrative systems and methods as described herein embodying various aspects of the present invention are shown, it will be understood by those skilled in the art, that the invention is not limited to these embodiments. Any of the steps described herein may be implemented as computer-executable instructions embodied in a computer-readable medium, such as a computer disk or memory.
[0120] Modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. For example, each of the elements of the aforementioned embodiments may be utilized alone or in combination or subcombination with elements of the other embodiments. It will also be appreciated and understood that modifications may be made without departing from the true spirit and scope of the present invention. The description is thus to be regarded as illustrative instead of restrictive on the present invention.
[0121] One or more aspects of the invention may be embodied in computer-executable instructions, such as in one or more program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other device. The computer executable instructions may be stored on a computer readable medium such as a hard disk, optical disk, removable storage media, solid state memory, RAM, etc. As will be appreciated by one of skill in the art, the functionality of the program modules may be combined or distributed as desired in various embodiments. In addition, the functionality may be embodied in whole or in part in firmware or hardware equivalents such as integrated circuits, field programmable gate arrays (FPGA), application specific integrated circuits (ASIC), and the like.
[0122] Embodiments include any novel feature or combination of features disclosed herein either explicitly or any generalization thereof. While embodiments have been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and techniques. Thus, the spirit and scope of the invention should be construed broadly as set forth in the appended claims. | Embodiments are directed to broadcast roaming, i.e., providing service/content to a terminal from a visited service provider. An embodiment is directed to sending a roaming rule request to a service provider, receiving a roaming rule response from the service provider, acquiring service guide fragments from the service provider and processing the service guide fragments in accordance with the received roaming rule response, sending to a selected service provider a service provisioning request for a purchase item, receiving from the selected service provider a service provisioning response regarding the purchase item, and accessing service and/or content related to the purchase item, wherein the service and/or content is provided by the visited service provider. Embodiments are directed to exchanging between a visiting service provider and a home service provider of the terminal a roaming authorization request regarding a purchase item and a roaming authorization response regarding the purchase item. | 7 |
FIELD OF THE INVENTION
The invention relates to a field of integrated circuit manufacture using phase shift masking in the optical lithographic patterning process.
BACKGROUND OF THE INVENTION
Optical lithography has been the technique of choice employed for forming circuit patterns in integrated circuits. Typically, ultraviolet light is directed through a mask. A mask is similar in function to an "negative" which is used in ordinary photography. However, the typical mask has only fully light transmissive and fully non-transmissive regions as opposed to an ordinary negative which has various "gray" levels. In the same manner as one makes a print from a negative in ordinary photography, the pattern on the mask can be transferred to a semiconductor wafer which has been coated with a photoresist layer. An optical lens system provides focusing of the mask patterns onto the surface of the photoresist layer. The exposed photoresist layer is developed, i.e. exposed/non-exposed regions are chemically removed. The resulting photoresist pattern is then used as a mask for etching underlying regions on the wafer.
In recent years, demands to increase the number of transistors on a wafer have required decreasing the size of the features but this has introduced diffraction effects which have made it difficult to further decrease the feature size. Prior to the work of Levenson, et. al., as reported in "Improving Resolution in Photolithography with a Phase Shifting Mask," IEEE Transactions on Electron Devices, VOL., ED-29, Nov. 12, December 1982, pp. 1828-1836, it was generally thought that optical lithography would not support the increased density patterning requirements for feature sizes under 0.5 microns. At this feature size, the best resolution has demanded a maximum obtainable numerical aperture (NA) of the lens systems. However, the depth of field of the lens system is inversely proportional to the NA, and since the surface of the integrated circuit could not be optically flat, good focus could not be obtained when good resolution was obtained and it appeared that the utility of optical lithography had reached its limit. However, the Levenson paper introduced a new phase shifting concept to the art of mask making which has made use of the concepts of destructive interference to overcome the diffraction effects.
Ordinary photolithography, with diffraction effects, is illustrated in FIG. 1(a)-1(d). As the apertures P1 and P2 become closer, N becomes smaller, and as seen in FIG. 1(b), the light amplitude rays which pass through P1 and P1 start to overlap due to diffraction effects. These overlapping portions result in light intensity at the wafer, FIG. 1(d), which impinges on the photoresist layer. Accordingly, due to diffraction, the intensity of the wafer no longer has a sharp contrast resolution in the region between P1 and P2.
As illustrated by FIG. 2(a) to 2(e), it is possible to make use of the fact that light passing through the masking substrate material, FIG. 2(a), 51, (and FIG. 2(b), 51') exhibits a wave characteristic such that the phase of the amplitude of the light exiting from the mask material is a function of the distance the light ray travels in the substrate material, i.e., thickness t 1 and t 2 . By making the thickness t 2 such that (n-1)(t 2 ) is exactly equal to 1/2λ, where λ is the wavelength of the light in the mask material, and n=refractive index of the added or subtracted natural material, then the amplitude of the light existing from aperture P2 is in opposite phase from the light exiting aperture P1. This is illustrated in FIG. 2(c) showing the effects of diffraction and use of interference cancellation. The photoresist material is responsive to the intensity of the light at the wafer. Since the opposite phases of light cancel where they overlap and since intensity is proportional to the square of the resultant amplitude, as seen in FIG. 2(d), contrast resolution is returned to the pattern.
FIG. 2(a) and FIG. 2(b) illustrate two different techniques for obtaining the interference phase shifting. In FIG. 2(a), the light transverses through a longer distance via deposited layer 52. In FIG. 2(b), the light in region P2 transverses through a shorter distance by virtue of an etched groove 52' in the wafer 51'.
Phase shifting masks are now well known and there are many varieties which have been employed, as more fully set out in the article by B. J. Lin, "Phase-Shifting Masks Gain an Edge," Circuits and Devices, March 1993, pp. 28-35. The configuration of FIG. 2(a) and FIG. 2(b) have been called alternating phase shift masking (APSM). Several researchers have compared the various phase shifting techniques and have shown that the APSM approach is the only known method proven capable of achieving resolution 0.25 microns and below, with depth of field as large as ±0.34 microns with an I line stepper. Alternating PSM can be implemented in dark and light field mask versions. If the dark field strategy is employed for alternating PSM, a negative tone photoresist must be employed and if the light field version is employed, a positive photoresist must be chosen. The positive resist portion which is exposed to UV is removed during development and vice versa for negative resist.
As illustrated in FIG. 2(e), the process for making and using binary masks have been highly computerized. The designer of complex integrated circuits now works at a computer terminal and specifies a circuit design on a computer which requires compliance with certain predetermined design rules, 80. The initial design is validated using a design rule checker software 88. Accordingly, when the functional design is completed, a computer aided design tool program 81 automatically creates a digital bit map or vector file called a PG Tape 82 which represents the data in a standard and known data format for manufacturing the mask to accomplish the design. These digital files are then used to control automatic processes for manufacturing the masks, typically resulting in a magnified, e.g. 5×, physical reticle, 83, containing the mask pattern for each layer of the integrated circuit. The mask is then typically installed in a wafer stepper (a step and repeat optical tool) 84, which automatically carries out the lithographic exposure repeatedly on the wafer 87 by exposing the photoresist layer 85 at a physical location and moving the wafer, i.e. stepping, and repeating the same exposure at an adjoining location.
To date, due to various difficulties, alternating phase shifting masks have not generally been able to be designed automatically by the mask creation programs. This has required mask designers to expend time consuming and tedious manual analysis and has greatly increased the expense of producing PSM.
The problem with alternating PSM is that the dark field/negative resist strategy does not perform well for non-dense line patterns and the light field/positive resist strategy creates unwanted opaque lines corresponding to the 0°/180° transitions in the mask.
Accordingly, in order to employ alternating PSM for isolated patterns, it is necessary to solve the problems with the light field/positive resist strategy and to develop a method for automatically creating compensation or trim masks for eliminating the effect of unwanted opaque lines which form along 0°/180° transitions.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a method for improving the patterning of integrated circuits using light field photolithography with positive photoresists.
It is a still further object of the invention to simplify the design of phase shift masking for the gate level patterning of an integrated circuit which compensates for 0°/180° transition effects.
It is yet a still further object to provide a method to define a phase shift mask for the gate level patterning which provides phase shift elements to improve the dimensional control of the gate level pattern only in the integrated circuit region where the gate pattern overlays the active area pattern of the integrated circuit.
It is a still further object to provide a PSM method which enables maximally reduced gate patterns in the integrated circuit region where the gate pattern overlays the active area pattern of the integrated circuit.
It is a still further object to manufacture integrated circuits having better critical dimension control of the gate level pattern using the improved PSM methods of this invention.
It is a still further object to provide a process which automatically analyzes an IC logic circuit design and provides a digital file according to an accepted standard for manufacturing an alternating PSM for logic circuits.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1(a) to 1(d) are schematic representation of diffraction effects using a prior art ordinary binary transmission mask in photolithography.
FIGS. 2(a) to 2(d) are schematic representation of diffraction effects and the use of prior art phase shift masking (PSM) to compensate for the effects of diffraction.
FIG. 2(e) is illustrative of the mask production and IC photolithographic production process.
FIG. 3 is illustrative of a sample IC design showing the active areas (N and P) pattern and an overlay of the pattern of a gate level.
FIG. 4 is illustrative of the area of the Intersection of the active area and gate level including the designation of 0 degree and 180 degree phase shift regions according to this invention.
FIG. 5 is a redrawing of FIG. 4 illustrative of only the 180 degree phase shift regions of the sample design of FIG. 3.
FIG. 6 is a version of a resulting PSM of the invention for the example of FIG. 3 showing gate contact opaque chrome lines and the transition compensation regions surrounding the 180 degree regions.
FIG. 7 is a version of alternative PSM for the example of FIG. 3 showing gate contact opaque chrome lines and the 180 degree regions without surrounding transition compensation regions.
FIG. 8 is a version of trim mask for use following exposure by the mask of FIG. 7 to avoid lines caused by 0°/180° transition.
FIGS. 9(a) to 9(c) are cross sections illustrative of the alignment of a trim mask transparent aperture center line with the abutting line of the 0°/180° regions of the non-transition compensated mask of FIG. 8.
FIG. 10 is a flow diagram for the procedure to manufacture an alternating PSM with compensating transition regions and reduced gate lengths and to perform photolithography using said alternating light field PSM and positive photoresist.
FIGS. 11(a) and 11(b) illustrate the standard gate metal design and the reduced gate design respectively.
FIGS. 12(a) to 12(d) are illustrative of several configurations of transition compensation region shifter embodiments.
DETAILED DESCRIPTION OF THE INVENTION
It generally believed by those skilled in PSM lithography that a mask employing a light field is not able to be automatically designed by computer for integrated circuit application in the design of alternating PSM layouts. Light field designs use opaque regions on the PSM mask to correspond to the location and shape of the conductive lines, typically doped low resistivity polysilicon, or tungsten silicide or the equivalent, to be formed on the resulting wafer and positive photoresist must be employed in combination with the light field mask. This light field design with PSM has a very significant advantage for logic gate layout in that it provides improved resolution in connection with isolated gates. However, it also has the disadvantage that dark lines form along every abutting 0°/180° region. To date, light field alternating PSM have needed to be designed by examining manually each PSM design and by either inserting a compensating phase shift transition region separating each 0° region from each 180° region or by manually designing a trim mask to be used in conjunction with a PSM which has no phase shift compensating regions.
To simplify and provide an automatic solution to the alternating PSM problem, I propose an approach for designing a light field alternating PSM which appears to work reliably for logic circuits and for reliably shrinking gate size for logic circuits. The underlying premise of my approach is to apply the alternating phase shifts only to those regions of the gate level PSM mask where the gate lines provided by a standard gate level pattern design would overlay the regions in which active semiconductor (N and P) are to be formed. In Boolian algebra, where X is a first function and Y is a second function, the common overlay region is called the intersection and is designated Z=X∩Y. (This is also called the "AND" function. ) Hereinafter, the overlay region is designated the "Intersection."
With reference to FIG. 3, there is shown, for purposes of illustration, a computer generated printout, in scale, of the aerial view of the layout of "doped" active regions, 30-38 of a circuit to be formed in the integrated circuit semiconductor wafer. Also shown in FIG. 3 overlaid on the active region layout, are computer generated solid black lines, representing the gate pattern, 40-49, called poly lines, which have been printed to the same scale as the active area and in this aerial view of FIG. 3 are positioned exactly as they would be positioned with respect to the active area on the target circuit. Assuming that the width dimensions of the poly lines of this design needs to be so narrow that optical diffraction effects would degrade the image of the mask if constructed by ordinary binary photolithography, then application of my invention method is needed to automatically make a alternating light field PSM and integrated circuits with such mask.
FIG. 4 contains hash marked areas 50 which represent the computer generated Intersection of the poly gate lines 40-49 of FIG. 3 and the semiconductor wafer active area regions 30-38 of FIG. 3. There are many ways to establish the Intersection plot. One approach is to have a computer perform the logical AND function, i.e. X.Y, pixel by pixel, where X is the active area spatial representation of FIG. 3 and Y is the gate level spatial pattern of FIG. 3. FIG. 4 also includes the outline region of the active area of FIG. 3. Next, the computer is employed to apply a scheme for automatically assigning zero degree and 180 degree regions on opposite sides of the Intersection. It is seen in FIG. 4 that the computer analyzes and then assigns a zero degree and a 180 degree region on opposite sides of each Intersection long dimension. There are constraints on the program for allocating phase selection for a given area: (1) every Intersection longer dimension must have a 0° and 180 ° border section; and (2) the 180 degree region and the zero degree region on each side of an Intersection along the longer dimension should have a minimum width W i and have an area around it which can be used as a compensation region. The compensation region should have width W c . If the area between two Intersections is less than (2W i +W c ) then the area between the Intersections needs to be merged into a single phase 0° or 180° region.
FIG. 4 is redrawn in FIG. 5 except that the outline of zero degree areas has been deleted so that the FIG. 5 labels only the π regions. The remaining region is assumed to be zero phase. However, as noted earlier, it is recalled that one of the problems with light field designs is that, unless compensated, a dark line is formed on the wafer which corresponds to the line where the 180° region abuts a 0° region. Accordingly, in FIG. 6, a region called the transition region 51 is shown formed between every 180° region and its adjoining zero degree region. The only portion of the periphery of the 180 degree region which are not interfaced by a transition region 51 is where the 180° region abuts the intersection regions 50. FIG. 6 also includes opaque line regions 41-49 which are overlaid on the compensated 180 degree regions, so that FIG. 6 is the aerial representation of one embodiment of the final computer generated light field alternating PSM for a single exposure to produce the gate level poly pattern depicted in FIG. 3. In a single exposure step, assuming a positive resist is employed on a wafer, if a PSM is manufactured according to FIG. 6 design, the gate layered circuit of FIG. 3 aerial view will be able to be produced.
Alternatively, a two step exposure method can also accomplish the gate level poly patterns depicted in FIG. 3. FIG. 7 is identical to FIG. 6 but without any compensating transition region surrounding each 180 degree region. As noted, when exposing in a first step the positive photoresist on the wafer with a light field PSM of the form of FIG. 7, dark lines will be imaged along the line where 180° regions abut 0° regions. These unwanted dark lines can then be removed by a second exposure of the wafer through the "trim" mask of FIG. 8, provided no development is carried until completion of both exposure steps. The trim mask is transmissive along every 0/180 degree region abutting line so that the second exposure of the positive photoresist results in exposure and hence removal of the dark lines during resist development. FIGS. 9(a)-9(c) are further explanatory of one embodiment of the alignment and construction of a trim mask. FIG. 9(a) is a cross section of a deposited 180 degree phase shift region 100 which has an abutting transition line 110 between the 180 degree region and the zero degree region, 102. In FIG. 9(b) an etched shifter 105 is illustrated and the transition 110' between the zero and 180 degree region also is shown. A trim mask 107 for the shifter masks of FIG. 9(a) and 9(b) is shown in FIG. 9(c). The trim mask 107 is aligned so that the center 111 of the transmission region 112 is aligned with the transition or 110'. The UV light which transmits through the trim mask falls on the positive photoresist and exposes that region so that it will be removed during development of the resist. (It is noted that it is understood by those skilled in the art that following resist development, the non-exposed photoresist remains in place over the top of the region to be retained. Since the photoresist is over the top of a polysilicon or metal layer, after the resist is removed and the wafer is etched, the remaining resist protects the lines beneath it so that the uncovered poly (metal) on the wafer surface is removed, leaving the desired gate contact pattern.
With reference to FIG. 11(a) and FIGS. 12(a)-12(d), a compensation transition region 51 configuration embodiment is depicted. The transition region 51 can be constructed of step regions, preferably two or more step regions, such as 120 degrees (71) and 60 degree (70) interposed between the n region and the zero degree region. A single π/2 step region may also work in some instances. Physically, these stepped phase transition regions should have a minimum width 0.2 λ/NA, where λ is exposure wavelengths and NA is numerical aperture of the stepper and can be configured according to FIG. 12(a) for a deposited shifter or 12(b) for an etched shifter. Alternatively, the transition region can also have more steps or be a graded transition according to 12(c) or 12(d) for deposited or etched PSM respectively.
FIG. 11(b) discloses a further embodiment of the PSM gate level design method. I have determined that it is possible to employ the dark natural line formed at the Intersection which coincides with the abutting of the 180/0 degree regions to create the narrowest possible gate. For example, using a stepper with a numerical aperture of 0.5, a partial coherence factor 0.5 for the light source, and an exposure wavelength of 365 nm, and an alternating PSM, this minimum gate was 0.2 microns. As shown in FIG. 11(b), as another alternative, I provide a very narrow opaque line, 75 on the mask as shown which would overlay the 0/180 degree natural dark abutting transition. This narrow opaque line is very slightly narrower than the natural width of 0.2 microns, such as 0.18 microns or whatever increment is required to provide reliability in manufacturing yield.
This narrow opaque line is desirable for three reasons: 1) by concealing the phase edge it reduces the displacement of the wafer image caused by misalignment of the phase shift layer to the opaque layer on the mask; 2) it reduces line width error at the abutting 180/0° transition caused by misalignments of phase layers where a multiple phase step method is used; and 3) the opaque line, typically chromium, provides a more robust mask to etching than the photoresist, providing a steeper etched profile.
The natural line width for a stepper is defined as 0.25* λ/NA; where λ is the excitation wavelength and NA is numerical appeture.
The procedure described above is more fully illustrated in the flow diagram of FIG. 10. Specifically, block 120 depicts the AND operation to determine the Intersection of the active area pattern and poly gate contract pattern. Next, in block 121, all gates which are narrower than the minimum width achievable without phase shift masking are identified. Block 122, depicts a subclassification step which identifies groupings of minimum width gates which are contiguous and where the gate to gate spacing is too close for transition regions, i.e. less than 2W i +W c . These groupings are called "stacks". Gates which are not in a stack are classified as isolated gates 126. Next, the "stacks" identified in block 122 are further subclassified into branch, 123, odd 124, or even 125 stacks.
The odd stacks are groups in which an odd number of minimum gate intersections occur on a common active area bordered by a spacing on both sides which is large enough for a transition region. In block 130, these odd stack regions are to be phase shifted by applying 180° phase shift to the left most region and then progressively alternating the phase from 180° to 0° and 0° to 180° for regions between gates progressively from left to right.
In block 125, the even stack regions are groups where an even number of intersections occur on a common active area bordered by a spacing large enough for a transition region. The strategy here is to apply 0° phase shift to the left most region and progressively alternating the phase from 0° to 180° to 0° for regions between gates progressively from left to right.
For isolated regions 126, one side of the gate is to provided with a transition compensation region, i.e. graduated or steps of phases to eliminate the formation of an unwanted line.
Branch regions are regions in which parts of a single active region is bordered by more than two minimum gates. This contrasts to the odd and even stack. The shift strategy for such branch stack regions is to select one phase, either 180° or 0°, for the central region having more than two Intersections, and then working outward in all directions, alternating phase as one crosses each gate.
In block 132, the data for each type of stack and for isolated gates is reassembled and then verified by the Design Rule Checker 133 to confirm and verify that all minimum gates have 180° or 0° phase one side and not on the other side of each long dimension.
In block 134, the transition regions are generated for every location where 180°/0° regions abut such as at the short side of a gate and at the edge of a stack. Alternatively, as depicted earlier, the transitions could be replaced by a separate trim mask for which the data is now generated.
Finally, the output data called GDS2 is created for the mask generation. The FRACT software module of the Dracula program supplied by Cadence Design System will create GDS2 in the MEBES standard file format for an e-beam mask writer. For phase shifting type masks, data for more than one layer are output to create the poly reticle and the FRACT module will create the tape output containing all the layers required to create the phase shift mask and the trim mask if this alternative is elected.
The positive photoresist used in this invention are available commercially under numerous tradenames. The invention is not limited to these currently used resists.
The reticles typically are made from amorphous silicon dioxide, i.e. synthetic quartz, and the opaque material is typically chrome. Any opaque material could theoretically be used in place of chrome for this invention and the invention is not dependent on the specific material employed.
The figures of this document depict embodiments of this invention and are not intended to limit the scope of the invention. The scope of claims shall be construed in accordance with the claims. With this in view, | A method of performing poly level lithography in manufacturing an integrated circuit using a phase shift mask in a step and repeat optical tool where the phase assignment for said phase shift mask is determined by a technique which determines, without assignment conflict, the Intersection of the gate pattern with the active gate pattern and which divides the Intersection into categories of stacks where a slightly different phase assignment rule is employed for the different stacks. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to electric power supply apparatus of a type in which by means of semiconductor devices a first unidirectional input voltage is switched so as to reverse its polarity at a relatively high freqeuncy. The switched voltage is fed to a transformer the output of which is rectified to produce a second unidirectional output voltage, usually differing from the input voltage. Such a system is usually referred to as a voltage converter, and will be so called in this specification. The unidirectional input to the converter may itself be obtained by rectification of an alternating current supply.
Voltage converters of the above type are known, see for example U.S. Pat. to Crowe et al No. 4,164,014 which discloses what are known as half-bridge and push-pull converters and U.K. Pat. No. 1,459,885 which discloses what is known as a full-bridge converter. Although these inverters have been known for some little time, it has proved difficult to provide a regulated output from them. This has usually meant that if a regulated output was required it was necessary to supply the converter with a regulated input, or to use a very crude form of control known as burst-fire control by switching the converter off and on at intervals so that over a long period of time the output could be considered stable. Such a control system is disclosed in the above-mentioned British Pat. No. 1,459,885.
SUMMARY ON THE INVENTION
The invention has for its object ot provide an improved voltage converter which includes means for regulating the output voltage to maintain it at a regulated value, substantially independent of changes of the unidirectional input voltage and of the load conditions on the output of the converter.
According to the present invention there is provided a voltage converter comprising a source of a first unidirectional voltage, switching means for applying said first unidirectional voltage alternately in opposite polarities to a primary winding of a transformer, an inductance connected in series with said primary winding, and means for rectifying an alternating voltage appearing on a secondary winding of the transformer to develop an output at a second unidirectional voltage, wherein said switching means comprises two transistors each having a respective drive winding of the transformer connected between its base and emitter, said transformer having a third winding connected in series with said primary winding so that load currents drawn from said output and reflected into the converter transformer primary circuit cause an increase in the current in the drive winding of the conductive transistor, and wherein the inverter transformer is provided with a further winding connected to further switching means for shorting the further winding whereby to control the frequency of switching of the transistors.
BRIEF DESCRIPTION OF THE DRAWINGS
Features and advantages of the invention will appear from the following description of an embodiment thereof, given by way of example, and the accompanying drawings, in which:-
FIG. 1 is a circuit diagram partly in block form of a volage converter; and
FIGS. 2 to 4 are waveform diagrams illustrating the operation of the converter shown in FIG. 1.
DETAILED DESCRIPTION
In the voltage converter shown in FIG. 1, an alternating current supply, which may be of conventional supply voltage and frequency (240v, 50 HZ), is applied to input terminals 10 and by means of bridge rectifier BR1 and filter capacitor C1, produces a first unidirectional voltage between conductors 11 and 12. Between these conductors is connected a series combination of two unidirectional transistor switching devices, joined at a junction point J1. The switching devices are formed by transistor Tr1,Tr2 each in series with a respective diode D1, D2. A saturable transformer T1 has a first secondary winding T1a connected between the base of transistor Tr1 and the common junction point J1 of the transistor and switches a second secondary winding T1B connected between the base of transistor Tr2 and the negative conductors 12. Also shunted between conductors 11 and 12 is the series combination of two further capacitors C2 and C3, having a junction point J2. In a manner to be described, voltages appearing between points J1 and J2 are fed to the primary winding T2a of a transformer T2.
Junction point J1 is connected to one end of winding T2a by way of the primary winding of a transformer T1c and by way of an inductor L2 while junction point J2 is connected to the other end of winding T2a by way of the primary winding of transformer T3. Transformer T2 has two series-connected secondary windings T2b and T2c and the voltage appearing across these windings is rectified by a rectifier, comprising in this embodiment diodes D3 and D4, and is filtered by a filter comprising an inductor L1 and capacitor C4, the latter being shunted by a bleed resistor R1. The filtered unidirectional output appears at output terminals 13.
Transformer T1 operates in conjunction with transistors Tr1 and Tr2 to produce periodic reversals of the voltage applied to the primary winding T2a of transformer T2 and the rectified and filtered output feeds any load circuit connected to terminals 13. When current is drawn from terminals 14, a load is reflected back to the primary winding of transformer T2 and must be provided by that one of the two transistors Tr1, Tr2 which is then supplying current. If transistor Tr1 is conductive, additional base current will be induced in winding T1a, due to the flow of current in winding T1c which, being in series with winding T2a, carries the reflected load current. The transformer T1 is designed to saturate in operation, and the transformer will be driven to the point of saturation by the progressively increasing current in winding T1a due to the constant voltage drop presented by the base emitter voltage Vbe of transistor Tr1 together with the forward voltage drop Vf of diode D1. When, due to this saturation, the voltage of winding T1a is insufficient to overcome the voltage (Vbe+Vf) the transistor will be turned off.
When transistor Tr1 turns off, the rate of change of flux in the core of transformer T1 reverses and this flux change induces in winding T1b a voltage in a sense to cause transistor Tr2 to conduct. The current passed by transistor Tr2 flows through the winding T2a of transformer T2 in a direction producing a flux opposite to the current of transistor Tr1.
The time now taken to saturate transformer T1 depends on the base-emitter voltage drop of transistor Tr2 and the forward voltage drop of D2. When saturation occurs, transistor Tr2 ceases to conduct in a manner similar to transistor Tr1.
The converter thus far described has the ddisadvantage that the output voltage appearing at terminals 13 is sensitive both to the load applied to those terminals and also to the input voltage applied to terminals 10 and therefore means are provided to reduce such output voltage changes.
The method of control of output which is provided in a converter embodying the invention is based on the fact that the transistors Tr1 and Tr2 will switch between their alternative states in a cyclic manner and at a particular frequency which is determined by the circuit constants. Further, it can be arranged that the waveform of the pulses which are applied to the primary winding T2a of transformer T2 are such that at certain periods of the cycle there is a lesser contribution to the integrated output from the transformer, that is, that the output is not a true 1:1 square wave. Then, by changing the switching intervals, the integrated output can be controlled.
The above description of FIG. 1 has made no reference to the functions of the inductor L2, of the transformer T3, or of a further winding T1d on transformer T1. Briefly, inductor L2 modifies the waveform of the current fed to transformer T2, transformer T3 senses current changes occurring in transformer T2 and suitable processing means applied to winding T1d a signal which controls the instants of switching of transistors Tr1 and Tr2.
Consider first the operation of inductor L2. If a potential difference is applied instantaneously between the points J3 and J4 which form the ends of the series combination of the inductor L2 and primary winding T2a of transformer T2, and equal and opposite back e.m.f. is generated, substantially all of this e.m.f. appearing across the inductor, so that a negligible voltage is applied to the winding T2a, while the current in L2 rises progressively. This condition will continue until the rising current in the inductor reaches the value of the load current reflected into winding T2a from the windings T2b and T2c. When this point is reached, the current through inductor L2 ceases to change and therefore the back e.m.f. collapses and the voltage across the inductor diminishes to a low value. At this time, substantially the whole of the voltage appearing at points J3, J4, is applied to the winding T2a. By normal transformer action, voltages are produced in windings T2b and T2c and these are rectified and smoothed by the filter L1 and C4, to supply the load at terminals 13. The output voltage is proportional to the time integral of the voltage applied to the filter input points J5, J6 because of the integrating effect of the filter.
If the output load current should increase then the current through inductor L1 will increase proportionally but the rate of rise of current is constant so that, for a given width of voltage pulse appearing at terminals J3, J4, the time taken for the current to rise to a value equal to the reflected current in winding T2a will increase. Thus, if the load current increases the voltage-time integral at terminals J5 and J6, at the output of the rectifiers D3, D4 will decrease. Conversely, for a decrease in load current the voltage time integral at terminals J5, J6 will increase.
The operation may be better understood from the waveforms of FIG. 2. FIG. 2A shows the idealized waveform 20 appearing at points J3, J4 and FIG. 2B, the waveform of the current through the inductor L2. The first part 21 of each waveform of FIG. 2B shows a constant rate of change and the second part 22 has a reduced slope which is due to the magnetizing current of the transformer T2. The resulting voltage appearing across the inductor is shown in FIG. 2C and the complementary voltage appearing across the winding T2a is shown in FIG. 2D. The output voltage will be proportional to the voltage time integral represented by the shaded area 23. The waveform of the increased current through the inductor is shown in FIG. 2E and the voltage across the inductor due to the increased current of waveform 2E is shown in FIG. 2F. The shorter pulses which appear across winding T2a in these conditions is indicated in waveform 2G, from which it will be noted that the shaped area 23' representing the time integral has diminished as a result of the increased current.
The above description assumes that the output transformer T2 is substantially free from leakage reactance. It has been found that if the frequency of operation is high enough, even such a transformer starts to exhibit losses due to leakage reactance and these losses can be used to replace the inductor or at least reduce its value. Thus, although an inductor L2 is shown, in practice it may be that there will be no separate inductor in the circuit, the leakage reactance losses of the transformer T2 being sufficient to provide the operation outlined above due to the inductor L2.
Means are provided to vary the frequency of the cyclic operation of the switching stage including transistors Tr1 and Tr2. For this purpose a voltage sensitive oscillator state, controlled by voltage developed from the output voltage appearing at terminals 13, is preferably used. The oscillator advantageously comprises two transistors Tr3 and Tr4 which, with resistors R2 to R5 and capacitors C5 and C6 are cross-connected in a manner which resembles a conventional multivibrator.
Normally, a multivibrator circuit has a frequency of operation which is not especially sensitive to the voltage between the supply conductors, but with this circuit this is not the case. With a conventional multivibrator, if the supply conductor voltage is Vr, as indicated in FIG. 1, the aiming voltage of the time constant circuits consisting of R4 and C5, and R5 and C6 is approximately twice Vr and when a voltage of Vr is reached transition between states of the two transistors occurs. In this type of operation the time constant is 0.69 CR. However, in the circuit described the aiming voltage of the time constant circuits is (Vr+Vbe) and the transition point of the transistors Tr3 and Tr4 is reached when the voltage value of 2 Vbe is attained. Accordingly, the transition point is dependent upon the value of Vr, a higher value of Vr resulting in an increase of frequency of operation and a lower frequency of operation for a lower value of Vr.
To produce the control voltage for controlling the ramp generator, an integrated circuit type voltage regulator IC1 is used, such as a regulator Type 723. As is well known, such a voltage regulator has a terminal for a stable reference voltage. The regulator has two comparator input terminals 4 and 5. To terminal 4 is applied a reference voltage obtained from the voltage at terminal 6 by a resistor R18 and to the other terminal 5 is applied a voltage from the positive output terminal 13, by a potential divider consisting of resistors R6 and R7. At its output terminal 11 the regulator will produce a voltage which is proportional to the difference between the voltages at its input terminals 4 and 5. The regulator receives a unidirectional supply voltage +V1 from a supply conductor fed from a small voltage supply unit S, fed from the input alternating voltage at terminals 10.
The voltage at the ramp generator supply conductor Vr is derived from the voltage at the supply conductor +V1 through a control transistor Tr5. The base of the transistor is normally at a voltage obtained from potential divider R8, R9 connected to conductor +V1 and the voltage at the ouput of the regulator is fed to the junction point J7 of the two resistors R8 and R9. Transistor Tr5 thus controls the current fed to the ramp generator stage and so controls the frequency of operation. Output from the ramp generator is taken from the collectors of transistors Tr3 and Tr4; the output voltages are supplied to the bases of further transistors Tr6 and Tr7 respectively, which have collector resistors R10 and R11 fed from the conductor +V1. The collectors of transistors Tr6 and Tr7 are connected respectively to the bases of two further transistors Tr8 and Tr9, which have collector resistors R12 and R13 fed from the conductor +V1.
Transistors Tr6 to Tr9 thus act as power amplifying stages, and the output, taken from the collectors of transistors Tr8 and Tr9, is fed to a further winding T1d on transformer T1.
The ramp generator is designed so that there is a transitional state of the transistors such that transistors Tr8 and Tr9 in the operating cycle are both conductive for a short period, and thereby present an effective short circuit on the winding T1d of transformer T1. If this short circuit occurs during the time that, for example, transistor Tr1 is conducting, then the flux linkage between winding T1c and widning T1a will be ineffective and the current flow in winding T1a will cease, causing transistor Tr1 to turn off and become non-conductive. It is arranged that the frequency of operation of the ramp generator is somewhat higher than the natural frequency of operation of the oscillatory circuit including the transformer T1 and transistors Tr1 and Tr2 so that the operation of this circuit is susceptible to control by the ramp generator in this way. The frequency of the oscillating circuit is thus controlled by the frequency of the ramp generator, in turn controlled by the output voltage of the converter.
When supply voltage is first applied to the circuit or at very low output load currents there is insufficient current in winding T1c for the self-oscillatory action of Tr1, Tr2 and T1 to take place and under these conditions Tr8 and Tr9 provide sufficient drive current to turn Tr1 and Tr2 on and off in the manner of a driven converter. The bleed resistor R1 across the filter capacitor C4 provides a small output current at no load conditions to maintain stability around the negative feedback loop.
The circuit can also be made current sensitive and it is for this purpose that transformer T3 is used. With this operation, when the maximum permitted current is being drawn from the converter, and the load conditions are such as to intend to increase the output current beyond this point, the frequency of the ramp generator is further increased, for the increasing load. By this means it can be arranged that the output current remains at a constant value and the output voltage drops for any increase in load above the permitted maximum. The current is sensed by transformer T3, feeding a rectifier BR2 of which the output is filtered by a capacitor C7 and a resistor R14. The rectified output voltage is applied to a potential divider comprising two resistors R15 and R16, and a proportion of the voltage is applied to the base of a transistor Tr10. The collector of Tr10 is connected through a resistor R17 to the junction point J7 and so contributes to the base voltage of transistor Tr5.
If the reflected current through the primary winding T2a of transformer T2 is constant then the time that the full supply voltage is applied across inductor L2 is constant. Hence, the output voltage is proportional to the voltage time integral remaining in each switching cycle and by increasing the frequency the output voltage will decrease, thus providing a constant current output up to the point where short circuit conditions exist at the output terminals 13.
FIG. 3A shows the current flowing in winding T1a of transformer T1 under natural frequency conditions and FIG. 3B shows the corresponding waveform when the current flow is curtailed by the application at the instants 24 of a short circuit to the winding T1d.
FIG. 4 illustrates the operation of the current action resulting from an increase in cyclic frequency with constant maximum current in the primary winding of the converter transformer. Waveform A of FIG. 4 shows the variation with time of the current flowing in the primary winding T2a of converter transformer T2, the excursion of this current being limited to a value Im, when the system is operating at a first frequency f 1 . Waveform B illustrates the resultant voltage appearing between points J5 and J6 of FIG. 1, the sum of the voltage-time integrals represented by the shaded areas 51 representing the available output from the converter.
Waveform C of FIG. 4 illustrates the current in T2a when operating at a frequency higher than f 1 , with the excursion again limited to Im. The resultant voltage at J5, J6, shown in waveform D shows how the voltage-time integral represented by shaded areas 52 is reduced as compared with waveform B, so that the output current is appropriately limited.
The circuit shown in FIG. 1 is a so-called half-bridge converter. The same control methods can be applied to other known forms of converter such as push-pull and full bridge types.
Values of components suitable for use in the embodiment of FIG. 1 are given below:
______________________________________ Transistors ResistorsTr1 R1- 120 ohms BDY 93Tr2 R2 1 kilohmsTr3, Tr4 R3 2N2369 R4Tr6-Tr9 5.6 kilohmsTr5 R5Tr10 BC 187 Diodes R6- 15 kilohmsD1 R7- 7.5 kilohms 1N5402D2 R8- 6.2 kilohmsD3 R9- 56 kilohms BXY 61D4 R10- 2 kilohmsD5 R11 Capacitors R12 1 kilohmC1- 470 μF R13C2 R14- 510 ohms 1 μFC3 R15- 5.6 kilohmsC4- 2200 μF R16- 560 ohmsC5 R17- 6.2 kilohms 2.2 nFC6 R18- 4.7 kilohmsC7- 1. μF R19- 47 kilohmsC8- 0.1 μ F R20- 20 kilohms______________________________________
Transformer T1 turns ratios 5:5:1:30 for windings T1a:T1b:T1c:T1d
Inductance L2≈30 μH at 25 KHz. | Voltage converter apparatus is disclosed having circuitry for regulating the output voltage to maintain it at a regulated value. Use is made of switching devices that switch between their alternative states in a cyclic manner and at a particular frequency which is determined by the circuit constants. An inductance is provided for modifying the waveform of the current fed to the output transformer, so that at certain periods of the cycle there is a lesser contribution to the integrated output--i.e., the output is not a true 1:1 square wave. Then, by changing the switching intervals, the integrated output can be controlled. A current transformer is provided for sensing current changes occurring in the output transformer, and a short circuit arrangement is provided for short circuiting a control winding of the converting transformer to control the instants of switching of the switching devices. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to presses, and particularly to a simple press suitable for cheese making and having latching means for holding the press in a pressure applying position to which it can be moved manually.
Many different forms of presses are known for applying a wide range of operating pressures: most known presses are either screw operated or hydraulically operated, but they all have the common disadvantage of being complex and expensive. Moreover, for applications involving foodstuffs known such presses are also difficult to keep entirely clean: this latter is of particular importance since contamination of foodstuffs must be rigorously avoided.
In the above exemplary application for presses of the present invention, that is in the manufacture of cheese, the press is ued to remove the whey from curds produced when milk and milk products are treated with appropriate baccilli at controlled temperatures. The degree of pressure exerted at this stage in the cheese making process has an important effect on the type of cheese produced, the greater pressure providing harder cheeses. Although screw operated or hydraulically operated press have in the past been used for this purpose, the complexity of their component parts does make it difficult for them properly to be maintained sterile. Absolute sterility is an essential requirement since infection of the curd during the cheese making process with baccilli other than that or those with which the curd is deliberately impregnated will modify the characteristics of the eventual cheese thereby spoiling the process. Another factor influencing the cheese making process is the fact that when the curds and whey are initially compressed, the resistance to compression does not remain constant, but reduces as the whey is gradually expelled from the curd. Since this is a relatively slow process, it is necessary to adjust the pressure at regular intervals over a relatively long time. This involves continual supervision.
OBJECT OF THE INVENTION
It is the object of the present invention to provide a press which, in addition to being simple and therefore easily maintained sterile (and also economical to produce), is able to accommodate a change in volume of the material being pressed in order to maintain pressure on the article being pressed.
SUMMARY OF THE INVENTION
The present invention, in one aspect, provides a press comprising a pressure member, a reaction member formed by the base of the press, and guides projecting from said base along which the pressure member is displaceable, in which there are provided friction latching means which, in an operative position, are operable to resist the displacement of the pressure member away from the reaction member while permitting displacement of the pressure member towards the reaction member.
In another aspect the present invention provides a press comprising a pressure assembly displaceable along guides projecting from the base of the press towards or away from a reaction member formed by said base, the pressure assembly comprising first and second pressure members resiliently biased away from one another, the first pressure member lying between the second pressure member and the reaction member along the guide, and the second pressure member being provided with a friction latching mechanism which, in an operative position is operable to resist displacement of the pressure assembly away from the reaction member.
Thus, when set, the pressure assembly is itself stressed with the first and second pressure members being in a position where they stress the resilient biasing means so that any change in the volume of the material being pressed by the press is accommodated by displacement of the first pressure member under the action of the resilient biasing means, the second pressure member being latched in position on the guides.
Preferably the latching mechanism is one which engages automatically in the latched position without requiring any manual or other displacement in order to effect latching. In the preferred embodiment the latching mechanism includes a catch element for the or each guide, the or each catch element being rockable and having an operative position in which it frictionally engages the guide in such a way that relative movement between the catch element and the guide in one direction reinforces the engagement to jam or wedge the element and the guide agains further movement, and relative movement in the opposite direction frees the catch element to permit such movement to continue.
In the preferred embodiment of the invention the press is adapted for operation in such a position that the guides are generally upright with the pressure assembly displaceable up and down along them, and the catch elements are retained in their operative position by gravity so that they automatically adopt the latching position as the pressure assembly is pressed down onto anything positioned between the pressure assembly and the reaction member.
The catch element may be provided with an aperture through which the guide passes and the sides of which engage against the surface of the guide to jam or wedge the catch when it is in its operative position: in this case the catch element is preferably a substantially flat plate which rests on a support which displaces one edge or side of the plate away from the surface of the pressure member on which it is carried, when in the operative position thereof.
In the preferred embodiment of the invention there are two substantially parallel guides and the pressure assembly comprises a first yoke extending transverse the two guides and engaged thereon for displacement towards or away from the reaction member, and a second yoke also guided on the guides and resiliently biased away from the first yoke, the second yoke carrying the said catch element.
The catch elements may be plates which rest on the said second yoke, one end of each plate forming a catch element resting on a raised projection carried by the yoke, and the other end of the plate having the said aperture through which the guide passes.
In the preferred embodiment of the invention the aperture in each catch plate is constituted by a generally cylindrical hole the axis of which is inclined with respect to the normal to the plane of the plate, the mouth at each end of the hole being enlarged in a direction lying in a plane including the axis of the generally cylindrical hole and the normal to the plane of the plate in such a way as to permit the plate to rock about an axis perpendicular to this plane.
Other features and advantages of the present invention will become apparent from a consideration of the following description, with reference to the accompanying drawings, of a preferred embodiment, which is provided by of nonrestrictive example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic side view of the embodiment;
FIG. 2 is an enlarged sectional view of a part of the embodiment showing a catch element in its operative position; and
FIG. 3 is an enlarged sectional view of part of the embodiment showing the catch element in a release position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1, 2 and 3 illustrate a press which comprises a base 2 from which project upwardly two parallel guides 1. The base 2 forms a reaction member with respect to which pressure can be applied by acting on the guides 1 in a manner which will be described in greater detail below.
Slidably mounted on the guides 1 is a pressure assembly comprising a first yoke 5 and a second yoke 4 each of which have two apertures through which the guides 1 pass. Between the yokes 4 and 5, and surrounding the respective guides 1 are compression springs 6 which act to urge the first and second yokes away from one another.
The normal operating position of the press would be with the base 2 resting on a substantially flat generally horizontal surface so that the guides 1 project substantially vertically. Resting on the upper or second yoke 4 are two catch elements 3 each of which is in the form of a rectangular plate having a single aperture 3a passing therethrough. The aperture 3a is generally circular in plan, and has a generally cylindrical side wall 3b having an axis, inclined to the normal to the plate 3, and indicated by the broken line A--A. The mouth, at each end of the aperture 3a is flared outwardly at points 3c and 3d respectively. The outwardly flared portions 3c and 3d extend from approximately the middle of the thickness of the plate 3, and are located on diametrically opposite sides of the hole with the flared portion 3c being directed towards the upper face of the plate 3 and flared portion 3d approaching the lower face of the plate 3. The flared portions 3c, 3d are centred on a plane which includes the axis A--A and the normal to the plate 3.
Each of the plates 3 is supported on the second yoke 4 and spaced slightly therefrom by a spacing element 11 which is located adjacent a guide 1. The height of the spacing element 11 is related to its distance from the adjacent guide 1 and to the angle of inclination of the flared portions 3c, 3d of the apertures 3a in the plates 3 in such a manner that, as more clearly shown in FIG. 2, each plate 3 rests on the support 11 about which it rocks to a position where the sides of the hole 3a jam against the guide 1. In this position, termed a first or jamming position, the plate 3 is solely supported by the projection 11 and the engagement of the sides of the hole 3a with the guide 1. The plate 3 projects slightly over the edge of the yoke 4 to enable the plate 3 to be raised manually to the position shown in FIG. 3 termed a second or free position, where the guide 1 enters the flared portions 3c, 3d so that it is free to move in either direction through the hole 3a.
As will be appreciated, in the position shown in FIG. 2, the catch plates 3 jam against the guides 1 so that any force applied upwardly, that is in the direction of the arrow A of FIG. 2 will tend to increase the force of engagement between the plate 3 and the guide 1 thereby securely jamming or wedging the two members together. If, on the other hand, a force is applied to the yoke 4 downwardly, that is in the direction opposite that of the arrow A, the plate 3 can be turned clockwise or anticlockwise as seen in FIGS. 2 and 3 thereby permitting the plate 3 to slide down the guide 1. On release of the force on the yoke 4, however, the plate 3 readopts the operative position shown in FIG. 2 where it jams against the guide 1 and prevents the yoke from being displaced upwardly. Lifting the projecting edges of the plates 3, however, will free the jamming action and permit the yoke 4 to be moved up or down the guides 1 in either direction.
In use of the press a shallow tray 9 is placed on the base 2 and carries a container 8 which is filled with the material, such as cheese curd, to be compressed. A follower 7 which fits the container 8 like a piston is then superimposed on the curd and the pressure assembly lowered until the first or lower yoke 5 engages the upper surface of the follower. Pressure is then exerted on the upper or second yoke 4 to compress the spring 6 and exert the required pressure on the follower 7, compressing the contents of the container 8 to the required degree. When the pressure is released from the uper yoke 4 the jamming plates 3 are in the operative position illustrated in FIG. 2 and therefore resist any upward movement of the yoke 4. As whey is expelled from the container 8 the contents of this container reduce in volume and this change is accommodated by extension of the springs 6 which urge the first or lower yoke 5 downwardly onto the follower 7.
Although, as shown in FIG. 3, the catch plates 3 can be simply raised to release the pressure assembly they may alternatively be turned about an axis parallel to the guides 1, which are preferably in the form of rods, to a position where they disengage from the spacing elements 11 which are in the form of studs and lie flat on the yoke 4 in a position where they exert no influence on the movement of the yoke 4. | A press suitable for making cheese comprises a pressure assembly which is displaceable along guides projecting from the base of the press towards or away from a reaction yoke member formed by the base, the pressure assembly being constituted by first and second members which are resiliently biassed away from each other. Friction catches are provided which, in an operative position, frictionally engage the guides to resist displacement of the pressure assembly away from the reaction member. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a door latch system for a door of a switchgear enclosure and more particularly to a door latch system for a door of a switchgear enclosure wherein all the components of the door latch system are located outside the door for ease of repair.
2. Description of the Related Art
The terms switchgear and switchboard are general terms which cover metal enclosures which house switching and interrupting devices such as fuses, circuit breakers, relays, inner connections and supporting structures, including assemblies of these devices with associated fuses, interconnections and support structures used for the distribution of electric power.
Most switchgears presently produced include an exhaust system for venting gas and debris particles generated by an electric arc under arc-fault conditions. During an arc-fault explosion, the temperature and pressure inside the switchgear increase very rapidly and the rapid pressure build-up can damage the switchgear and its components. Exhaust systems such as that disclosed in US Published Patent Applications US 2009/0212022 and 2010/0258532 are designed to vent the gas and debris particles from the switchgear enclosure during an arc-fault explosion. Even though the venting systems of the prior art perform generally satisfactorily, the doors of the switchgear enclosure are subjected to large internal pressures which may cause the doors to “blow” open thereby subjecting workers in the area to possible injury.
Door latch systems have been previously provided in an attempt to prevent the enclosure doors from opening during an arc-fault explosion. However, the components of the prior art door latch systems are located within the door or within the enclosure at the inside surface of the door. If one of the components of the prior art door latch system should fail, it is impossible, or very difficult, to open the door to gain access to the failed component. In such a situation, it may be necessary to cut a large hole in the door to gain access to the failed component so that the door may be opened to perform the necessary repairs on the door.
SUMMARY OF THE INVENTION
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key aspects or essential aspects of the claimed subject matter. Moreover, this Summary is not intended for use as an aid in determining the scope of the claimed subject matter.
A door latch system is provided for the doors of a switchgear enclosure. The doors of the switchgear may be of the walk-in type or the non-walk-in type. The doors of the switchgear enclosure of the non-walk-in type will usually be located in the front panel of the enclosure. If the door or doors are of the walk-in type, the door or doors will usually be located in the rear panel of the enclosure. In the present invention, the only difference between the door latch systems utilized with the walk-in type and the non-walk-in type doors is that in the walk-in type door latch system, a door jamb may be bolted to the rear panel which extends around the door opening.
This summary will be directed to the door latch system for the walk-in type door. A door opening is provided in the rear panel of the switchgear enclosure which has an upper edge, a lower edge, a first side edge and a second side edge. An optional jamb is welded to the exterior surface of the rear panel around the door opening and includes an upper jamb member, a lower jamb member, a first side jamb member and a second side jamb member. A door is provided which includes an upper end, a lower end, a first side, a second side, an inner surface and an outer surface. The door in the rear panel will be described as if the optional jamb is not utilized.
The first side of the door is hingedly secured to the rear panel adjacent the first side edge of the door opening, about a vertical axis, by a plurality of vertically spaced-apart first hinges. A plurality of externally threaded studs are secured to the rear panel adjacent the second edge of the door opening and extend outwardly therefrom in a vertically spaced-apart manner. A plurality of second hinges are provided each of which includes a first part and a second part which are pivotally secured together by a vertically disposed pivot pin. The first part of each of the second hinges is secured to the outer end of one of the studs which extend from the rear panel adjacent the second side edge of the door opening. The second part of each of the second hinges is secured to an elongated and vertically disposed angle member having first and second walls which are transversely disposed with respect to one another. The second part of each of the second hinges is secured to the first wall of the angle member. The angle member is selectively movable between latched and unlatched positions.
A plurality of vertically spaced-apart door latches, having inner and outer ends are secured to the angle member for movement therewith and extend horizontally therefrom. At least one of the door latches has a handle associated therewith. Each of the door latches has a latch pin opening formed therein outwardly of the inner end thereof.
A vertically-disposed and generally channel-shaped door latch housing is secured to the outside surface of the door adjacent the second side thereof. The housing defines an interior compartment having upper and lower ends. A latch handle is pivotally mounted on the housing which is movable between latched and unlatched positions. The latch handle includes a shaft which extends into the interior compartment of the housing. The housing has a plurality of vertically spaced-apart and horizontally disposed slots formed therein.
A plurality of first latch plate assemblies are secured to the housing in the interior compartment thereof in a vertically spaced-apart manner between the shaft of the latch handle and the upper end of the housing. Each of the first latch plate assemblies includes vertically spaced-apart and horizontally disposed upper and lower latch plates. Each of the upper and lower latch plates of the first latch plate assemblies have first and second openings formed therein.
A plurality of second latch plate assemblies are secured to the housing in the interior compartment thereof in a vertically spaced-apart manner between the shaft of the latch handle and the lower end of the housing. Each of the second latch plate assemblies includes vertically spaced-apart and horizontally disposed upper and lower latch plates. Each of the upper and lower latch plates of the second latch plate assemblies have first and second openings formed therein.
A first elongated actuator rod, having upper and lower ends, has its lower end coupled to the shaft of the latch handle and extends upwardly therefrom through the first openings in the upper and lower latch plates of the first latch plate assemblies. A second elongated actuator rod, having upper and lower ends, has its upper end coupled to the shaft of the latch handle and extends downwardly therefrom through the first openings in the upper and lower latch plates of the second latch plate assemblies. The pivotal movement of the latch handle from its unlatched position to its latched position causes the first actuator rod to move upwardly and causes the second actuator rod to move downwardly. The pivotal movement of the latch handle from its latched position to its unlatched position causes the first actuator rod to move downwardly and causes the second actuator rod to move upwardly.
A plurality of first latch pin assemblies are mounted on the first actuator rod in a vertically spaced-apart manner with each of the first latch pin assemblies having a latch pin extending vertically upwardly therefrom. The movement of the latch handle from its unlatched position to its latched position causes the latch pins of the first latch pin assemblies to move upwardly with the first actuator rod so as to be received by the second openings in the upper and lower latch plates of the first latch plate assemblies.
A plurality of second latch pin assemblies are mounted on the second actuator rod in a vertically spaced-apart manner with each of the second latch pin assemblies having a latch pin extending vertically downwardly therefrom. The movement of the latch handle from its unlatched position to its latched position causes the latch pins of the second latch pin assemblies to move downwardly with the second actuator rod so as to be received by the second openings in the upper and lower latch plates of the second latch plate assemblies.
The door may be moved to its closed position when the angle member is in its unlatched position. The latch handle is then moved to its unlatched position if not already done so. The angle member is then moved to its latched position which causes the latches secured thereto to move into the interior compartment by way of the slots formed in the housing. The latch pin openings of the latches are then vertically aligned with the latch pins of the first and second latch pin assemblies. At that time, the second wall of the angle member is pressed against the outside surface of the door. The latch handle is then moved to its latched position which causes the latch pins to be moved into the second openings of the upper and lower latch plates of the first and second latch plate assemblies to securely latch the door in its closed and latched position.
During use, if any of the components of the door latching system should fail and require repair while the door is closed, the components are easily reached since all components are located at the outer side of the door.
It is a principal object of the invention to provide an improved switchgear door latch system.
A further object of the invention is to provide a switchgear door latching system which locks the door of the switchgear enclosure from the outer side thereof.
A further object of the invention is to provide a switchgear door latch system wherein all of the components of the system are located at the outer side of the door.
A further object of the invention is to provide a switchgear door latch system which will prevent the door of the switchgear enclosure from opening during an arc-fault explosion.
A further object of the invention is to provide a switchgear door latch system which may be used with practically any size door.
A further object of the invention is to provide a switchgear door latch system which is durable in use.
These and other objects will be apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.
FIG. 1 is a front perspective view of a switchgear enclosure;
FIG. 2 is a perspective view of a support which extends around the door opening;
FIG. 3 is a perspective view of the door latch system of this invention associated with a door in the rear panel of the switchgear enclosure;
FIG. 4 is a perspective view of one of the latches of this invention which has a handle associated therewith;
FIG. 5 is a perspective view of a latch utilized in the system;
FIG. 6 is a partial exploded perspective view of a portion of the door latch system;
FIG. 7 is a perspective view of the door latch system;
FIG. 8 is a partial elevational view of the inside of the housing portion of the door latch system and a portion of the latching mechanism therein;
FIG. 9 is a partial perspective view of the lower portion of the housing positioned at the outside surface of the door;
FIG. 10 is a partial perspective view of the portion of the housing and associated latching structure; and
FIG. 11 is a partial sectional view illustrating the manner in which the door latch system functions.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Embodiments are described more fully below with reference to the accompanying figures, which form a part thereof and show, by way of illustration, specific exemplary embodiments. These embodiments are disclosed in sufficient detail to enable those skilled in the art to practice the invention. However, embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. The following detailed description is, therefore, not to be taken in a limiting sense in that the scope of the present invention is defined only by the appended claims.
The numeral 10 refers to a conventional switchgear including an enclosure 12 having an upper end 14 , lower end 16 , front panel 18 , side panels 20 and 22 , and rear panel 24 . The numeral 26 refers to doors of non-walk-in type which are normally hingedly mounted on the front panel 18 and which may have various dimensions. Each of the doors 26 extend over a door opening 27 formed in front panel 18 . The numeral 28 refers to a door of the walk-in type which is normally utilized on the rear panel 24 to close the door opening formed therein. Each of the doors 26 and 28 have the door latch system of this invention associated therewith which is referred to by the reference numeral 30 . As seen in the drawings, the doors 26 may have the door latch system mounted at either the right side of the door or the left side of the door opposite to the supporting hinges of the door. For illustration purposes, the door 26 A at the upper right side of front panel 18 will be described in detail.
For purposes of description, the door opening 27 , which is closed by door 26 A, will be described as having an upper edge 32 , lower edge 34 , first side edge 36 and second side edge 38 . Preferably, a metal support or lip 40 extends from panel 18 around door opening 27 as seen in FIG. 2 . A resilient seal 42 is mounted on the lip 40 as seen in FIG. 11 and extends completely therearound.
Preferably, the upper, lower and side edges of door 26 A are provided with an inwardly directed flange 44 as seen in FIG. 11 . For purposes of description, the doors 26 will be described as having an upper end 46 , lower end 48 , first side 50 , second side 52 , inner surface 54 and outer surface 56 .
Door 26 is hingedly secured at its first side 50 to the outer surface 56 thereof by a plurality of vertically spaced-apart hinges 58 . The hinges 58 have one part thereof screwed or bolted to panel 18 and the other part thereof screwed or bolted to door 26 A at side 50 thereof about vertical axes in conventional fashion. The doors 26 are movable between open and closed positions.
A plurality of threaded studs 60 are secured to and extend from panel 18 in a vertically spaced and horizontally disposed manner and have lock nuts 62 threadably mounted thereon. The numeral 64 refers to a hinge which is secured to each of the studs 60 . Each of the hinges 64 include a bearing-like part 66 which is threadably secured to the outer end of the associated stud 60 and has a vertically disposed opening 68 extending therethrough. Hinge 64 also includes a part 70 having a head 72 and a stud 74 extending therefrom. Head 72 has an opening extending upwardly thereinto from the lower side thereof. Hinge 64 further includes a part 70 ′ which is identical to part 70 . Part 70 ′ includes a head 72 ′ and a stud 74 ′. Head 70 ′ has an opening 76 ′ formed therein which partially extends into head 72 ′. Parts 70 and 70 ′ are identical but are reversed with respect to one another. A washer 78 is positioned on the upper side of part 66 of said washer 80 and is positioned at the underside of part 66 . Pivot or hinge pin 82 is positioned in opening 68 of part 66 . Part 70 is positioned so that the upper end of hinge 82 is rotatably received by the opening in the underside of head 72 of part 70 . Part 70 ′ is positioned so that the lower end of hinge pin 82 is rotatably received by openings 76 ′ in head 72 ′ of part 70 ′. The parts of the hinges 64 are held together by the fact that the studs 74 and 74 ′ are received by openings 84 and 86 formed in an elongated angle member 88 and held therein by nuts 87 and 89 respectively. Angle member 88 will be described as having an upper end 90 and a lower end 92 with transversely disposed walls 94 and 96 . A plurality of horizontally disposed latches 98 are secured to angle member 88 by welding or the like in a vertically spaced-apart manner. Each of the latches 98 have an elongated latch pin opening 100 formed therein. One of the latches 98 has a handle 102 extending therefrom.
The numeral 104 refers to a channel-shaped latch housing having flanges 106 and 108 extending therefrom which have vertically spaced-apart openings 110 and 112 formed therein respectively. For purposes of description, housing 104 will be described as having an upper end 114 and a lower end 116 . Housing 104 defines an interior compartment 118 at its inner side. A plurality of vertically spaced-apart and horizontally disposed slots 120 are formed in housing 120 as seen in FIG. 7 which are adapted to receive the latches 98 . The handle 102 is not received by a slot 120 .
A latch handle 122 is rotatably mounted on housing between latched and unlatched positions and has a shaft 124 secured thereto which extends inwardly into compartment 118 of housing 104 . Shaft 124 is coupled to a conventional crank mechanism 126 . The lower end of an elongated actuator rod 128 is coupled to crank mechanism 126 and extends upwardly therefrom in compartment 118 . The upper end of an elongated actuator rod 130 is coupled to crank mechanism 126 and extends downwardly therefrom in compartment 118 . When latch handle 122 is moved from its unlatched position to its latched position, crank mechanism 126 causes actuator rod 128 to move upwardly and causes actuator rod 130 to move downwardly. Conversely, when latch handle 122 is moved from its latched position to its unlatched position, crank mechanism 126 causes actuator rod 128 to move downwardly and causes actuator rod 130 to move upwardly.
A plurality of vertically spaced-apart latch plate assemblies 132 are secured to housing 104 in compartment 118 by welding or the like with each assembly 132 including an upper latch plate 134 and a lower latch plate 136 which are vertically spaced apart. As seen in FIG. 9 , upper latch plate 134 is positioned above the associated slot 120 and lower latch plate 136 is positioned below the associated slot 120 . Each of the latch plates 134 in each of the latch plate assemblies 132 have a first opening 140 and a second opening 142 formed therein. Each of the latch plates 136 in each of the latch plate assemblies 132 have a first opening 144 and a second opening 146 formed therein. Openings 140 and 144 are vertically aligned and openings 142 and 146 are vertically aligned.
Actuator rod 128 movably extends through the openings 140 and 144 in those latch plate assemblies 132 which are positioned above crank mechanism 126 and actuator rod 130 movably extends through the openings 140 and 144 in those latch plate assemblies 132 which are positioned below crank mechanism 126 .
A plurality of latch pin assemblies 148 are secured to actuator rod 128 in a vertically spaced-apart manner and have latch pins 150 extending upwardly therefrom which are received by the openings 146 and 142 of those latch pin assemblies 132 which are positioned above crank mechanism 126 when a latch handle 122 is moved from its unlatched position to its latched position.
A plurality of latch pin assemblies 148 ′ are secured to actuator rod 130 in a vertically spaced-apart manner and have latch pins 150 ′ extending downwardly therefrom which are received by the openings 142 and 146 of those latch pin assemblies 132 which are positioned below crank mechanism 126 when the latch handle 122 is moved from its unlatched position to its latched position. When the latches 98 are in their latched positions, the latch pins 150 and 150 ′ also extend through the openings 100 in the latches 98 when the latch handle 122 is moved from its unlatched position to its latched position since the latches 98 are positioned between the upper and lower latch plates of the latch plate assemblies and the openings 100 are vertically aligned with the openings 142 and 146 of the latch plates 134 and 136 respectively.
The switchgear door latch system of this invention functions as follows. Assuming that the door 26 is in the open position and assuming that the angle member 88 with the latches 98 attached thereto is in the open or unlatched position and the latch handle 122 is in the unlatched position, the following steps take place. The door 26 is then moved from its open position to its closed position to close the door opening 27 . The angle member 88 is then moved from its unlatched position to its latched position wherein the wall 90 of angle member 88 will be moved into engagement with the outside surface of the door 26 , as illustrated in FIG. 11 which will cause the door 26 to move into engagement with the seal 42 . At that time, the latches 98 have been received by the slots 120 in the housing 104 . The latch handle 122 is then rotatably moved from its unlatched position to its latched position which will cause the actuator rod 128 to move upwardly so that the latch pins 150 will extend upwardly through the opening 146 in latch plate 136 , through opening 100 in the associated latch 98 and through the opening 142 in the latch plate 132 . At the same time, the actuator rod 130 will longitudinally moved downwardly so that the latch pins 150 ′ extend downwardly through the openings 142 in the latch plates 134 , extend through the opening 100 in the associated latch 98 and through the openings 150 ′ in the latch plates 136 . At that time, the door 26 will be latched in place and will prevent the door from moving to its open position should an arc-fault explosion occur within the enclosure. When one of the components of the system fails, it is not necessary to cut a hole in the door to repair the same since all the components of the system are located at the exterior side of the door 26 . For example, if there should be a problem within the housing 104 , the housing 104 may be removed from the door without the need of opening the door. The engagement of the latch pins with the latches and the engagement of the angle member 88 with the outer surface of the door ensures that the door will not open upon an arc-fault explosion occurring.
It can therefore be seen that a unique switchgear door latch system has been provided which accomplishes at least all of its stated objectives.
Although the invention has been described in language that is specific to certain structures and methodological steps, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific structures and/or steps described. Rather, the specific aspects and steps are described as forms of implementing the claimed invention. Since many embodiments of the invention can be practiced without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. | A switchgear door latch system is provided which prevents a door of a switchgear enclosure from opening should an arc-fault explosion occur within the enclosure. The door of the enclosure is latched from the exterior side of the door rather than on the inside of the door as is true in the prior at designs. All of the components of the latch system are located at the exterior side of the enclosure which facilitates repair of the same without cutting a hole in the door. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to the recovery of hydrocarbonaceous products from oil shale and oil/tar sands and, in particular, to a process and system for recovering such products and byproducts with significantly reduced environmental impact.
BACKGROUND OF THE INVENTION
[0002] The term “oil shale” refers to a sedimentary rock interspersed with an organic mixture of complex chemical compounds collectively referred to as “kerogen.” The oil shale consists of laminated sedimentary rock containing mainly clay with fine sand, calcite, dolomite, and iron compounds. Oil shales can vary in their mineral and chemical composition. When the oil shale is heated to above 250-400° F., destructive distillation of the kerogen occurs to produce products in the form of oil, gas, and residual carbon. The hydrocarbonaceous products resulting from the destructive distillation of the kerogen have uses which are similar to petroleum products. Indeed, oil shale is considered to be one of the primary sources for producing liquid fuels and natural gas to supplement and augment those fuels currently produced from petroleum sources.
[0003] Processes for recovering hydrocarbonaceous products from oil shale may generally be divided into in situ processes and above-ground processes. In situ processes involve treating oil shale which is still in the ground in order to remove the hydrocarbonaceous products, while above-ground processes require removing the oil shale from the ground through mining procedures and then subsequently retorting in above-ground equipment. Clearly, in situ processes are economically and environmentally desirable since removal of the oil shale from the ground is often expensive and destructive. However, in situ processes are generally not as efficient as above-ground processes in terms of total product recovery.
[0004] Historically, prior art in situ processes have generally only been concerned with recovering products from oil shale which comes to the surface of the ground; thus, prior art processes have typically not been capable of recovering products from oil shale located at great depths below the ground surface. For example, typical prior art in situ processes generally only treat oil shale which is 300 feet or less below the ground surface. However, many oil shale deposits extend far beyond the 300 foot depth level; in fact, oil shale deposits of 3000 feet or more deep are not uncommon.
[0005] Moreover, many, if not most, prior art processes are directed towards recovering products from what is known as the “mahogany” layer of the oil shale. The mahogany layer is the richest zone of the oil shale bed, having a Fischer assay of about twenty-five gallons per ton (25 gal/ton) or greater. The Mahogany Zone in the Piceance Creek Basin consists of kerogen-rich strata and averages 100 to 200 ft thick. This layer has often been the only portion of the oil shale bed to which many prior art in situ processes have been applied.
[0006] For economic reasons, it has been found generally uneconomical in the prior art to recover products from any other area of the oil shale bed than the mahogany zone.
[0007] Thus, there exists a relatively untapped resource of oil shale, especially deep-lying oil shale and oil shale outside of the mahogany zone, which have not been treated by prior art processes mainly due to the absence of an economically viable method for recovering products from such oil shale.
[0008] Another important disadvantage of many, if not most prior art in situ oil shale processes is that expensive rubilization procedures are often necessary before treating the oil shale. Rubilization of the in situ oil shale formation is typically accomplished by triggering underground explosions so as to break up the oil shale formation. In such prior art process, it has been necessary to rubilize the oil shale formation so as to provide a substantial increase in the permeability of the oil shale bearing rock formation. By increasing the permeability, the ability for gases and liquids to flow also increases, the potential to recover a more substantial portion of products therefrom. However, rubilization procedures are expensive, time-consuming, and often cause the ground surface to recede so as to significantly destroy the structural integrity of the underground formation and the terrain supported thereby. This destruction of the structural integrity of the ground and surrounding terrain is a source of great environmental concern.
[0009] Rubilization of the oil shale in prior art in situ processes has a further disadvantage. Upon destructive distillation of the kerogen in the oil shale to produce various hydrocarbonaceous products, these products seek the path of least resistance when escaping through the marlstone of the oil shale formation. By rubilizing the oil shale formation, many different paths of escape are created for the products; the result is that it is difficult to predict the path which the products will follow. This, of course, is important in terms of withdrawing the products from the rubilized oil shale formation so as to enable maximum recovery of the products. Since the products have numerous possible escape paths to follow within the rubilized oil shale formation, the task of recovering the products is greatly complicated and significant sub surface environmental issues become more of an issue. Including significant groundwater contamination.
[0010] Oil/tar sands, often referred to as ‘extra heavy oil,’ are types of bitumen deposits. The deposits are naturally occurring mixtures of sand or clay, water and an extremely dense and viscous form of petroleum called bitumen. They are found in large amounts in many countries throughout the world, but are found in extremely large quantities in the United States, Canada and Venezuela.
[0011] Due to the fact that extra-heavy oil and bitumen flow very slowly, if at all, toward producing wells under normal reservoir conditions, the sands are often extracted by strip mining or the oil made to flow into wells by in situ techniques which reduce the viscosity by injecting steam, solvents, and/or hot air into the sands. These processes can use more water and require larger amounts of energy than conventional oil extraction, although many conventional oil fields also require large amounts of water and energy to achieve good rates of production.
[0012] Certain improvements with respect to the recovery of products from shale are disclosed in U.S. Pat. No. 4,928,765. Unlike other prior art processes, the in situ body of oil shale to be treated is not rubilized. Rather, a gas-fired heater assembly is placed within a bore hole followed by the introduction of fuel gas and combustion air from above ground, both of which are regulated to maintain an initial start-up temperature of over 1000° F. and thereafter a constant temperature of below 1500° F. throughout a reaction zone formed in the surrounding shale bed. Specifically, a production temperature of 1200° F. was been found most desirable. By maintenance of this temperature, voids created in the reaction zone as kerogen is retorted to evolve natural gas, become black body radiators assisting to ensure a sustained, constant high volume extraction of natural gas devoid of any liquids.
[0013] Like all mining and non-renewable resource development projects, oil shale and sands operations have an effect on the environment. Oil sands projects may affect the land when the bitumen is initially mined and with large deposits of toxic chemicals, the water during the separation process and through the drainage of rivers, and the air due to the release of carbon dioxide and other emissions, as well as deforestation. Clearly any improvements in the techniques use to extract hydrocarbonaceous products from shale and sands would be appreciated, particularly if efficiency is improved and/or environmental impact is reduced.
SUMMARY OF THE INVENTION
[0014] This invention is directed to apparatus and methods of in situ recovering hydrocarbonaceous and additional products from nonrubilized oil shale and oil/tar sands. The method comprises the steps of forming a hole in a body of nonrubilized oil shale or sand, placing a heating source into the hole, and introducing a conductive and radiant non-burning thermal energy front sufficient to convert kerogen in oil shale or bitumen in oil sand to hydrocarbonaceous products.
[0015] The subsequent produced gases and hydrocarbonaceous products are withdrawn as effluent gas through the hole, and a series of condensation steps are performed on the effluent gas to recover various products. In the preferred embodiment, a negative pressure relative to the well inlet pressure is maintained to insure positive flow of the combustion and product gases, this is performed by a method of blowers on the effluent side of the well and the removal of mass during the condensation steps. Also in the preferred embodiment, one or more initial condensation steps are performed to recover crude-oil products from the effluent gas, followed by one or more subsequent condensation steps to recover additional, non-crude-oil products from the effluent gas. In conjunction with oil/tar sands, the method includes the step of providing an slotted permeable well casing/sleeve within the hole to limit excessive in-fill.
[0016] Such additional products may include ethane, propane, butane, carbon dioxide, methane, or hydrogen, depending upon the nature of the crude-oil products, contamination in the well, and other factors. Within the preferred embodiment, the composition of the well gases may be adjusted so that it contains approximately 1 percent oxygen or less. This will be done by inert flushing and or oxygen getters.
[0017] The subsequent condensation steps may be carried out in at least one cooled chamber having an input and an output, and a compressor system may be provided at the output of the cooled chamber to maintain the effluent gas at a negative pressure from the hole and through the initial and subsequent condensation steps. The cooled chamber preferably includes a plurality of critical orifices between multiple compressor stages sized to recover the additional gaseous products. The chamber may be cooled with liquid carbon dioxide or other liquids or refrigerant techniques, including carbon dioxide recovered from the effluent gas stream.
[0018] A carbon sequestration step may be performed wherein recovered carbon dioxide is delivered down the hole following the recovery of the hydrocarbonaceous products. A plurality of well holes may be drilled, each with a gas inlet to receive a heated and pressurized processing gas. The processing gas and hydrocarbonaceous products may be withdrawn as effluent gas through each hole, and a plurality of condensation steps may be used to recover crude oil products and the additional products from the effluent gas from a plurality of the holes. The cracking and subsequent removal of hydrocarbonaceous products and associated gases opens the kerogen pores and significantly increases permeability in the now depleted oil shale rock. Once depleted these now vacant pores, having charred surface areas significantly greater than other carbon sequestration processes can now adsorpt large volumes of carbon dioxide. As part of a carbon sequestration process, carbon dioxide may be introduced down a central well hole following the recovery of the hydrocarbonaceous products until the carbon dioxide is detected at one or more of the surrounding holes, thereby indicating saturation. This now represents a potentially significant increase in carbon sequestration potential over other techniques.
[0019] The crude oil products are typically recovered as a ratio of heavy crude to lighter crudes, in which case the flow rate of the processing gas may be adjusted to reduce the ratio. Alternatively, the reflux time of the heavy crude with respect to the initial condensation step may be increased to reduce the ratio. For that matter, one or more of the following parameters may be adjusted in accordance with the invention to vary the recovery of crude oil, other products or contaminants from the effluent gas:
[0020] the temperature, pressure or effluent extraction flow rate of the processing gas,
[0021] the residency time of the processing gas in the hole,
[0022] the reflux time of the crude oil with respect to the initial condensation step.
[0023] A basic system for recovering hydrocarbonaceous and other products from a hole drilled in nonrubilized oil shale and oil/tar sands comprises:
[0024] a down-well heater to convert kerogen in oil shale or bitumen in oil sand into hydrocarbonaceous products;
[0025] a gas outlet conduit for withdrawing the processing gas and hydrocarbonaceous products from the hole;
[0026] an initial condenser system for recovering crude oil products from the effluent gas; and
[0027] a subsequent condenser system for recovering additional products from the effluent gas.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a schematic drawing showing improvements to product recovery from a well;
[0029] FIG. 2 is a detail drawing of a third condenser unit;
[0030] FIG. 3 shows how depleted wells may be used for carbon sequestration; and
[0031] FIG. 4 is a simplified drawing of a casing applicable to oil and tar sand extraction operations.
DETAILED DESCRIPTION OF THE INVENTION
[0032] This invention is directed to the extraction of hydrocarbonaceous products from nonrubilized oil shale. The system and method are also applicable to recovery from oil sands and tar sands with appropriate engineering modification described in further detail herein.
[0033] Referring now to FIG. 1 , a hole 22 is drilled through an overburden 32 and into an oil shale body or formation 34 to be treated. A heater 40 is disposed within hole 22 . The heater may be of any suitable design, including a combustion heater, electric heater or radio-frequency (RF) or other heater. The heater 40 is powered or fueled by an above-ground energy source 42 through conduit 44 . In the case of a combustion heater, conduit 44 carries fuel whereas, in the case of electric or RF heaters conduit 44 brings electrical power.
[0034] If a combustion heater is used, the fuel at least partially derived from the effluent gas stream through processes described elsewhere herein. As such applicable fuels may include straight or mixtures of methane, ethane, propane, butane, and or hydrogen and so forth. Air is used only as a “make-up” gas into the combustor or from the blower, and the level of make-up air may be adjusted so that gas used for extraction has an oxygen content of 1 percent or less. The lower oxygen content in the processing gas is advantageous for several reasons. For one, higher levels of oxygen can auto-ignite down at the bottom of the well. In particular, oxygen content may be adjusted by changing the fuel mixture of the combustor to achieve a very rich fuel mixture, thereby diminishing the level of oxygen. Oxygen sensors are preferably provided to monitor O 2 content into and out of the well to maintain desired operating conditions.
[0035] The exhaust of the down hole combustor will be exhausted separately and like all burners, the combustor may only be 60 to 80 percent efficient. However, a boiler may be used to create steam, with the waste heat being used to run a turbine to create electricity as needed for different on-site operations and the exhaust can be used as make-up air.
Multi-Stage Condensation
[0036] An effluent gas conduit 26 is positioned around the opening of the hole 22 for receiving an effluent gas which includes hydrocarbonaceous products formed from the pyrolysis of kerogen and can include the process combustion gases. The effluent gas conduit 26 further serves to transfer the effluent gas to above-ground condenser units. This invention improves upon the collection side of the system as well through multiple stages of condensation, with the goal being to recover all liquid and gaseous products.
[0037] The preferred embodiment incorporates three stages of condensation. The first stage collects only the heavy crude. The second stage collects the light and medium crudes and water; the last stage collects gaseous products, including methane, ethane, propane, butane, carbon dioxide, nitrogen and hydrogen. As with the reduced-oxygen processing gas improvements described earlier, the use of multiple condensation stages is considered patentably distinct. That is, while the combination of the processing gas improvements and multiple condensation stages achieves certain symbiotic benefits in combination, the improvements to the injection side and the collection side of the well may be used independently of one another. This third condenser stage, in particular, is applicable to industries outside of the petroleum industry; for example, the general gas industry, the chemical industry, and others.
[0038] Cooling coils are typically used in the first two condenser stages. The invention is not limited in this regard, however, in that other known devices such as coolant-filled ‘thumbs’ may alternatively be used. All of the products recovered by condensers one and two are liquid products at STP. In the oil industry heavy, medium and light crudes are separated by API numbers, which are indicative of density. Heavy crude is collected from condenser # 1 , whereas light and medium crudes are collected by condenser # 2 . The light crude comes out with water, which is delivered to an oil-water separator known in the art. The heavy crude is preferably pumped back into a reflux chamber in the bottom half of condenser # 1 to continue to crack the heavy crude and recover a higher percentage of sweet and light crude products. This also creates more gas products in condenser # 3 .
[0039] The effluent flow rate is an important consideration in condensation, a distinction should be made between CFM (cubic feet per minute) and ACFM, or actual CFM, which takes temperature into account. At 1000° F. to 1400° F., the gases exiting could reach flow rates as high as 2000 ACFM depending on well depth and product content. Once the liquid products are removed and the gases get cooled down to 80° for condensation purposes, the flow rate gets reduced to approximately about 200 ACFM. These considerations are particularly important in the last condenser stage, which uses pressure loops and critical orifices to recover the individual gaseous products.
[0040] FIG. 2 is a detail drawing that focuses on the final stage of condensation. The condenser unit is actually a set of condensers enabling various components to be divided out in terms of temperature and pressure on an individualized basis. Condenser # 3 includes a sealed, insulated housing filled with a coolant, preferably liquefied CO 2 . Conveniently, the liquid CO 2 is recovered by condenser # 3 itself, as described in further detail below.
[0041] The inside of condenser # 3 is maintained at a temperature of about −80 to −100° F. from the liquid carbon dioxide. Immersed in the liquid CO 2 are a series of loops, each with a certain length, and each being followed by a critical orifice and a compressor loop that establishes a pressure differential from loop to loop. The length and diameter of each loop establishes a residency time related to the volume of the individual components within the gas mixture.
[0042] Each loop between each set of orifices and compressor loops is physically configured to control the pressure in that loop as a function of the temperature within the condenser, causing particular liquefied gases to become collectable at different stages. In FIG. 2 , loop 202 and critical orifice CO 1 are configured to recover propane and butane, which is collected at 210 . Loop 204 and critical orifice CO 2 are configured to recover CO 2 , which is collected at 212 . Loop 205 and critical orifice COn are configured to recover methane, which is collected at 213 . Loop 206 and critical orifice COf are configured to recover nitrogen, which is collected at 214 . Following the final critical orifice, COf, hydrogen is recovered. A compressor 216 not only compresses the collected hydrogen gas into a tank, in conjunction with product condensation and removal it creates a negative pressure back up the line, between condensers # 2 and # 3 , and all the way down into the well. The significance of this negative pressure will be addressed in subsequent sections.
[0043] The purity of the collected gaseous products may vary somewhat. Methane, for example, is quite pure, and the hydrogen is extremely pure. All of the gaseous products are collected in the liquid state, and all are maintained as liquids except hydrogen, which emerges as a gas and it not compressed into a liquid (although it could be). The propane may be mixed with butane, and may be kept as a combined product or separated using known techniques. To assist in the recovery of the gaseous products into a liquefied state, there is an initial storage tanks for these products built into the condenser or at least physically coupled to the condenser to take advantage of the cooled CO 2 from where the recovered products are then pumped into external pressurized storage tanks.
[0044] The only materials which pass through the critical orifices are in the gaseous state. In terms of dimensions, the input to condenser # 3 may have a diameter on the order of several inches. The critical orifices will also vary from ⅛″ or less initially down to the micron range toward the output of the unit.
[0045] As mentioned, the goal of this aspect of the invention is recover all products on the collection side of the well and, in some cases, use those products where applicable for processing gas formation or product collection. In addition to the collected liquid CO 2 being used to cool condenser # 3 , the combustible gases may be used to run the down hole combustor, particularly if the combustor has a BTU rating which is higher than necessary. For example, if the combustor needs a BTU in the 1000 to 1100 BTU range, combustible gasses like propane and butane collected from compressor # 3 may be mixed with recovered combustible gases such as low BTU gas like hydrogen or an inert gas like nitrogen to achieve this rating.
[0046] In terms of dimensions, condensers # 1 and # 2 may be on the order of 4 feet in diameter and 20 feet long, whereas compressor # 3 may be 2+feet by 8 feet, not including the compressors or the tanks. All such sizes, pipe diameters, and so forth, are volume dependent. Whereas, in the preferred embodiment, the injection and collection equipment may be used for multiple wells, such as 16 wells, but they could used for more or fewer with appropriate dimensional scaling.
[0047] Physical aspects of condenser # 3 will also vary as a function of the installation; in other words, the actual size of the loop within each phase may vary as a function of gas content which might be site-specific. Accordingly, prior to operation if not fabrication, an instrument such as an in-line gas chromatograph may be used to determine the composition of the flow into condenser # 3 . The analysis may then be used to adjust the physical dimensions of the unit; for example, to construct a condenser which is specific to that site in terms of what products and/or contaminants are being produced.
Use of the Venturi Effect
[0048] Referring back to FIG. 1 , the temperature differential of approximately 1400° F. to 650° F. across condenser # 1 . This establishes a negative pressure in view of the fact that liquid products are recovered from the unit. The same is true with condenser # 2 , which goes from approximately 650° F. to 250° and then another 200°, 180° temperature differential before the output goes to condenser number three.
[0049] Oil shale is present in various strata, with significant horizontal permeability and very little vertical permeability. The horizontal permeability of one layer might be quite different from the permeability of other layers. The use of compressor 216 in conjunction with pressure differentials across the condensers, establishes a negative pressure all the way down into the well. As vapor molecules leaving the well are pulled across the face of the rock, a Venturi effect is created that effectively draws the now heated kerogen out of these horizontally permeable strata. This action improves extraction, facilitating an active rather than passive collection of products.
Physical Parameter Adjustment
[0050] The combination of various physical parameters associated with the invention allows for a wide range of adjustments in overall operation. As one example, assume that the system is producing an undesirable high percentage of heavy crude. Several things may be done to rectify such a situation. Excess heavy crude may means that the kerogen is not being cracked as efficiently as it could be. One solution is to slow down the flow rate of the effluent gases thereby increasing the residency time of the heated gas. Alternatively, the temperature of the heater may be increased to enhance cracking down in the well, thereby reducing the amount of heavy crude. As a further alternative, reflux time in condenser # 1 may be increased. Such techniques may be used alone or in combination.
[0051] Indeed, according to the invention, various physical parameters may be adjusted to alter the ratio of products and/or the amount of gas collected in the end. These parameters include the following:
[0052] heater temperature;
[0053] effluent gas pressure;
[0054] effluent flow rate;
[0055] residency time;
[0056] reflux time;
[0057] condenser temperature; and
[0058] the negative pressure throughout the collection side of the system.
[0059] These parameters may be ‘tuned’ to maximize product output. However, such adjustments may have other consequences. For example, a higher processing gas residency time in the well might increase carbon monoxide production, which could lead to secondary effects associated with the liquids extracted, the oil liquid extracted, and/or the liquefied gases taken out of the third condenser.
[0060] The adjustment of physical parameters may also have an effect upon contaminant generation. Oil shale is a compressed organic material which contains elements such as sulfur from pyrite or other contaminants or minerals. One advantage of the instant invention is that the well is operated at a very reducing environment, preferably less than 1 percent oxygen, such that reactions with materials such as sulfur are minimized. Nevertheless, the physical parameters discussed above may be adjusted to reduce the level of contaminants such as sulfur.
Opportunities for Carbon Sequestration
[0061] Another advantage made possible by the invention is the opportunity for large-scale carbon sequestration. Certain existing carbon sequestration processes simply fill abandoned mines with carbon dioxide which, being heavier than air, ideally remains in place. However, cracks and fissures may exist or develop, allowing the gas to leak out. In addition, the large surface area of the mine is not used directly, thereby reducing the potential efficiency of the sequestration process.
[0062] According to this invention, when kerogen is cracked and removed from the wells recovery cylinder, the remaining product at high temperature exhibits a vast system of micropores that are coated with char. Resulting in an enormous surface area which allows for the direct adsorption of carbon dioxide. Accordingly, following a mining operation, carbon dioxide may be pumped down into the well to be adsorped by these porous materials.
[0063] FIG. 3 is a top-down view of a multi-well operation. The small circles depict the well holes, while the dashed lines indicated depleted kerogen. As the drawing shows, these depleted regions may overlap in places. According to the invention, a central well is selected for CO 2 injection. The injected gas migrates toward the other wells which are not being injected. If there were only one well, or if the depleted regions of multiple wells did not overlap, the injected CO 2 may ultimately find its way to the other wells through natural diffusion. However, this is an exceedingly slow mass transport process due to the fact that diffusion depends upon a concentration gradient. However, with overlapping regions of depleted kerogen a high degree of permeability exists from one well to another and a much more active mass transport process based upon dispersion or advection may occur, which is orders of magnitude faster than diffusion.
[0064] During this process, the uncapped wells around the injection well will be monitored, and when a sufficient level of CO 2 is detected, a desired level of saturation can be determined. Again, the CO 2 used for injection may be derived from the system itself, through the output of condenser # 3 , described above. As such, the CO 2 may be injected in liquid form. Overall, it may be possible to achieve a 70 to 80 percent replacement of volume for the cracked kerogen removed which would relate to multiple equivalent volumes of CO 2 by mass.
Modifications for Oil and Tar Sands
[0065] The systems just described may be useful not only in oil shale, but also in oil/tar sands with appropriate engineering modification. In oil shale, kerogen is cracked, which has a molecular weight on the order of 1000 Daltons or greater. With oil and tar sands bitumen is being cracked, which has a molecular weight of about half that of kerogen. In fact, when cracking kerogen, a transition occurs from kerogen to bitumen to oil products. As such, with oil and tar sand an initial high-temperature cracking and gasification step is not necessary. Temperatures on the order of 600° F. to 800° F. are useful as opposed to the 1200° F. to 1600° F. used for kerogen cracking and gasification. The first condenser described above may therefore be unnecessary.
[0066] In contrast to oil shale, oil/tar sands are generally not stratified but instead exhibit omnidirectional permeability. As such the use of the Venturi effect discussed above is not available. Additionally, since sands ‘flow,” provisions need to be made for the well casing to ensure against fill-in.
[0067] According to the invention, for oil/tar sand applications, a central, in-well pipe 402 with apertures 404 would be placed during the drilling operation. The apertures may include small holes, diagonal cuts, mesh features, and so forth, depending upon material composition and potential flow rate. For example, perforations on the order of an inch or thereabouts would be provided throughout the length of the pipe and, behind that (against the sands) a screen 410 with much smaller opening would be used. The holes may be cut or punched into the pipe at a vertical angle to restrict sands from falling back into the well hole. Materials similar to window screen could be used, though high-integrity type-304 stainless steel would preferably be used for construction.
[0068] To sink the well, a flat coring bit would be used, with the casing just described following directly behind that. The casing would be installed during the drilling process. The material removed during the drilling process would be pumped up through the casing. When the coring bit reaches its destination, it remains in position with casing situated above it. At this point the heater is lowered into the casing with conduits attached. | Apparatus and methods are disclosed for recovering hydrocarbonaceous and additional products from nonrubilized oil shale and oil/tar sands. A hole is formed in a body of oil shale or oil sand. A heater is positioned into the hole generating a temperature sufficient to convert kerogen in oil shale or bitumen in oil sand to hydrocarbonaceous products, these products are extracted from the hole as effluent gas. One or more initial condensation steps are performed to recover crude-oil products from the effluent gas, followed by one or more subsequent condensation steps to recover additional, non-crude-oil products. The subsequent condensation steps may be carried out in at least one cooled chamber having a sequence of critical orifices maintained at a negative pressure. Carbon sequestration steps may be performed wherein recovered carbon dioxide is delivered down the hole following the recovery of the hydrocarbonaceous products. Various physical parameters may be adjusted to vary the recovery of crude oil or other products or contaminants from the effluent gas. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to new and useful improvements in devices for moving auger assemblies, particularly relatively heavy auger assemblies. It should be appreciated that the movements referred to are relatively small movements which may be required in or around a farmyard or the like and the device is not intended for long distance moving of the auger assembly, under which circumstances, it is usually hitched to a tractor or other source of motive power.
The relatively heavy auger assemblies used today in farming operations, are extremely difficult to manoeuver manually and it is obviously not always convenient or economical to hitch such auger assemblies to a tractor for the relatively small movements often required in positioning such auger assemblies in relation to materials to be picked up from one location and discharged at another.
SUMMARY OF THE INVENTION
This particular invention is an improvement of my United States patent application Ser. No. 044,719, filed June 1, 1979 now Pat. No. 4,271,919, dated June 9, 1981.
The present invention overcomes disadvantages of the general method of moving relatively large augers and in accordance with the invention there is provided a drive attachment for auger assemblies which include supporting structure, a pair of ground engaging wheels mounted upon a transverse axle and supporting an auger tube and flight assembly; said drive attachment comprising in combination a frame secured to said supporting structure, a ground engaging wheel drive, a drive wheel axle spanning said frame and being journalled for rotation within said frame, said drive wheel being secured to said drive wheel axle, gear means operatively connected to said drive wheel axle, drive means for said gear means selectively connectable to a source of power and means associated with said drive means to rotate said drive wheel selectively in either direction.
Another advantage of the present invention is to provide a device of the character herewithin described which is simple in construction, economical in operation and otherwise well suited to the purpose for which it is designed.
With the foregoing in view, and other advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawings in which:
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of an auger assembly with the invention attached thereto.
FIG. 2 is an enlarged fragmentary side elevation of the invention per se.
FIG. 3 is an enlarged fragmentary side elevation of the connecting and disconnecting means for the main drive belt.
FIG. 4 is a top plan view of the invention per se.
FIG. 5 is a front elevation of the invention per se.
FIG. 6 is a fragmentary isometric view showing the reversing mechanism for the drive means.
In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
Proceeding therefore to describe the invention in detail, reference character 10 illustrates an auger assembly including an elongated cylindrical auger tube 11, an auger flight assembly therein indicated at the lower end thereof by reference character 12, a source of power 13 operatively connected to the auger flight by means of belt 14, support arms 15 which are also used to raise and lower the auger assembly in a conventional manner, and ground engaging wheels 16, one of which is shown mounted upon a transverse axle 17 all of which is conventional.
The invention collectively designated 18 comprises a frame collectively designated 19 including spaced and parallel upper and lower horizontal members 20 and 21 respectively, transverse members 22 and 23 and vertical corner members 24 and 25 extending downwardly from the rear and front ends 24A and 25A of the members 20 respectively and being connected to the lower horizontal members 21 to provide a box-like frame. This frame is supported upon the transverse axle 17 by means of pillow block bearings 26 or the like and extends forwardly therefrom.
A ground engaging drive wheel 27 is secured to an axle which is journalled between pillow block bearings 29 secured to the front sides of the lower ends 30 of the front vertical members 25 which extend below the connection to the front ends of the horizontal members 21 as clearly shown in FIG. 2. The weight of the device 18 normally maintains wheel 27 in contact with the ground unless it is desired to transport the auger by a tractor or the like. Under these circumstances, the device is pivoted clear of the ground by means of a lever 18A extending up from frame 19. It pivots upon bearings 26 and may be detachably held in the raised position by any convenient latch means (not illustrated).
A source of power shown schematically by reference character 31, may take the form of an electric motor or a small gasoline engine and this is mounted within the supporting structure of the grain auger assembly in any convenient location adjacent to the drive wheel 27. The drive shaft 32 of the motor 31 includes a belt pulley 33 secured thereto and an endless belt 34 extends around this pulley 33. A main cross shaft 35 is journalled transversely upon the rear end of the upper side of the frame 19 within pillow blocks 36 and a pulley 37 is secured to this shaft on one end thereof and belt 34 extends around this pulley thus rotating shaft 35 when the belt is in the operative or drive position as will hereinafter be described.
A belt tightening assembly is provided collectively designated 38 and is mounted upon one of the supports 15 of the auger assembly substantially below the drive pulley 33 of the motor 31.
This assembly includes a bracket assembly 39 secured around the tube 15 and carrying an angulated arm 40 thereon extending rearwardly therefrom.
A pivoted arm 41 is pivotally secured by one end thereof to the front end of the angulated arm 40 by means of pivot pin 42 and a sheave or pulley 43 is journalled for rotation within the distal end of this pivoted arm 41.
A fixed idler pulley 44 is mounted upon pivot pin 42 and engages inside the lower run 34A of the endless belt 34 as clearly illustrated in FIG. 2.
The idler pulley or sheave 43 engages the upper run 34B of the endless belt 34 upon the outer side thereof when the pivoted arm 41 is in position shown in full line in FIGS. 2 and 3 and the necessary tension to tighten this belt is provided by means of a tension spring 45 extending between the spindle 46 mounting the pulley 43 and a pin 47 extending from the lower end of the angulated arm 40.
This tension spring provides sufficient pressure on the sheave 43 upon the upper run 34B to tighten the belt sufficiently to transmit drive from pulley 33 to pulley 37. When the lever 41 is moved manually in the direction of arrow 48, the spring pulls it over center and against a stop 49 thus slackening the belt 34 and disconnecting the pulley 33 from pulley 37.
Drive means collectively designated 50 are provided within the frame 19 and are operatively connected to gear means collectively designated 51 which in turn is connected to the axle shaft 28 to which the drive wheel 27 is secured.
The gear means preferably takes the form of a casing 52 secured to the frame 19 and the axle 28 extends through this casing and is provided with a skew gear 53 secured thereto and within the casing.
A gear drive shaft 54 is journalled for rotation within the casing above the gear 53 and is provided with a worm gear 55A engaging the skew gear 53 with the drive shaft 54 extending rearwardly from the casing as clearly shown in FIG. 4.
The drive means 50 includes a drive pulley 55 secured to the other end of shaft 35 and rotated thereby.
A hollow shaft or sleeve 56 is journalled within the frame and within bearings 57 and a shaft 58 is also journalled within the frame and passes through the hollow shaft 56 and rotates independently therefrom.
A pulley 59 is secured to shaft 58 adjacent the front end thereof and a pulley 60 is secured to the hollow shaft also adjacent the front end thereof.
An endless belt 61 engages around pulley 55 with upper run 61A passing around a direction changing idler pulley 62 mounted in the frame with pin 63 guiding the change of direction of the belt. The belt then passes under the pulley 59, around the pulley and then around an adjustable idler pulley 64 mounted within a bracket 65 extending within the frame and it will be noted that this idler pulley 64 is at right angles to pulleys 59 and 60 and is situated therebetween and to one side thereof.
The belt 61 then passes over the top of pulley 60, around the pulley, around a direction changing idler pulley 66 and then back to pulley 55. It will therefore be appreciated that the run of the belt rotates pulley 59 in one direction and pulley 60 in the opposite direction together with the shaft 58 and hollow shaft 56 respectively.
A further pulley 67 is secured to the hollow shaft 56 adjacent the rear of the end thereof and a further pulley 68 is secured to shaft 58 also adjacent the rear end thereof with the two pulleys 67 and 68 being in substantial side by side relationship.
Corresponding pulleys 69 and 70 are secured to the portion of the drive shaft 54 extending rearwardly of the gear box 51 and a first slack belt 71 extends around pulleys 67 and 69 and a further slack belt 72 extends around pulleys 68 and 70.
Means are provided to tighten one or the other of the slack belts so that it will be appreciated that when the belt 72 is tightened, the drive shaft 54 will be rotated in the direction of arrow 73 and when this belt is loosened and belt 71 is tightened, the drive shaft 54 will be rotated in the opposite direction, namely in the direction of arrow 74 thus providing rotation in either direction of the drive wheel 27.
In this embodiment, a lever 75 is mounted for sliding movement in the direction of arrow 76, within the framework by conventional means (not illustrated) and this lever is reciprocated by means of a sliding cable 77 which is conventional and includes the stationary outer casing 78 and moving inner wire 79 which is connected to lever 75 via connecting lug 80.
A pair of cylindrical stub shafts 81 and 82 extend one upon each side of the lever or bar 75 with stub shaft 81 engaging the outer surface of belt 71 and stub shaft 82 engaging the inner surface of belt 72. It will therefore be seen that as the lever 75 is moved in the direction of arrow 76, either belt 71 or 72 are tightened with the other belt becoming slack.
The auger assembly is supported by a castoring tail wheel assembly collectively designated 83 secured adjacent the lower end of the auger tube 11 and the auger assembly may be manually steered by the rear end thereof by pushing it to one side or the other with the drive being provided by the drive wheel 27.
Finally, although one method is shown in the drawings for raising and lowering the wheel 27 relative to the ground, nevertheless a further method can be utilized (not illustrated). It is relatively simple to mount the frame members 24A so that they slide vertically to other members which are in turn secured to the clamp 26 around axle 17. Springs may normally react between the members secured to clamp 26 and the frame members 24A, urging the wheel 27 into contact with the ground and when it is desired to raise the wheel 27 clear of the ground, lever 18A may be modified to provide an over-center action to the frame members 24A and of course the remainder of the assembly, to raise the frame and the wheel 27 vertically against pressure of the springs which will return the wheel into contact with the ground when the position of the lever is reversed.
Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense. | Relatively heavy and large auger assemblies often used in present day farming are difficult to move and manoeuver around a farmyard or the like and it is not always convenient to hitch a tractor to such auger assemblies for relatively short distance moving. This invention includes a small electric or gasoline motor or engine which can be operatively connected to a small wheel which is mounted within a frame secured to the auger assembly framework and which engages the ground. Means are provided so that this small wheel can be rotated in either direction. A small castoring wheel assembly supports the rear end of the auger assembly and when the small wheel is operatively connected to the motor, the wheel may be rotated slowly thus enabling the auger assembly to be moved as desired. Directional control is by steering the rear end of the auger assembly manually. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention concerns the field of enhanced security features for smart, debit and credit cards as used in commerce. Specifically, a dynamically allocated security code is generated by the smart, debit or credit card which when analyzed by a payment processor or card issuing network approves or denies specific financial transaction from occurring thus reducing the risk of fraudulent activity with the card.
[0003] 2. Related Art
[0004] Most of online fraud occurs due to thief of a valid debit or credit card Primary Account Number (“PAN”), expiration date and security code that are stolen from the card holder without their knowledge. Typically, this theft of card data is accomplished when a card holder visits a merchant and an unscrupulous merchant employee captures the card data for later resale while returning the actual card to the card holder. With cameras built into most of today's mobile phones, card information can easily be captured when the card holder passes the card to unscrupulous merchant employees. Once stolen, the card data information is often parked for a short period of time (e.g. several months) so that the card holder cannot determine the location where the card information was stolen. After a suitable period of time has elapsed, the data card information and codes can be used for e-commerce transaction and cardholder may never notice the fraudulent purchases unless close examination is made of the bank/credit card statement.
[0005] Another way that card data is stolen is from hackers who manage to penetrate the internal firewalls of merchants, thus stealing card data stored by the merchants. In both scenarios, the card holder is typically not aware that their card information was stolen and sold to a third party such as a criminal organization until fraudulent transactions start appearing on the card holder's monthly statements.
[0006] One way for banks and credit card processors to combat credit and debit card fraud is to use security codes. These security codes are known by a variety of types of acronyms. Credit cards typically employ a Card Verification Value (“CVV” or “CVV2”), also known as a Card Security Code (“CSC”), Card Verification Data (“CVD”), Card Verification Value Code (“CVVC”), Card Verification Code (“CVC” or “CVC2”), Verification Code (“V-code” or “V code”), Card Code Verification (“CCV”), or Signature Panel Code (“SPC”). These security codes using different terminology help implement enhanced security features for smart, debit and credit card transactions by providing increased protection for merchants against credit card fraud. While American Express places its security code on the front of the card, most smart, debit and credit cards place their security codes on the back of the card forcing thieves to copy this information as well as a further step to discourage and make it slightly more difficult for thieves to capture the smart, debit and credit card information.
[0007] The original purpose of implementing three or four digit security codes was to ensure that card holders had the card in hands when making purchases. With the advent of online shopping, an increasing number of merchants started to store the security codes on their servers to speed up the online transaction process as a way to enhance the shopping convenience of the customer. Unfortunately, capturing this information helps thieves when the merchant's card data is hacked by sophisticated hackers and the smart/debit/credit card information along with the stored security codes are stolen removing the necessity for the thief to have the smart, debit or credit card in their physical possession. Thus, the use of security codes as a way to reduce fraudulent transactions is thwarted by the merchants themselves in their attempt to make online purchases easier for the customer.
[0008] Additional limitations exist on the use of debit and credit card security codes. The use of these security codes cannot protect against phishing scams where the card holder is tricked into entering the security code along with other card details via a fraudulent website. The growth in phishing is another reason why the use of security codes has reduced their real-world effectiveness as an anti-fraud device. For merchants who do not use security codes, their transactions are typically subjected to higher card processing costs and fraudulent transactions without security codes are more likely to be resolved in favor of the cardholder thus increasing the costs to the merchants.
[0009] Therefore, a need exists for dynamically generating card security codes that periodically change in order to stymie thieves from stealing the card information or rendering stolen data worthless in a short period of time after the theft of the card's security code data. A need also exists for a system a card issuer to support dynamically changing security codes so that financial transactions that take several weeks are not erroneously denied and identified as fraudulent because the card security code has changed during the time delay in processing the financial transaction for the card.
SUMMARY
[0010] This invention provides a dynamically generated security code for smart, debit and credit cards as a way to thwart fraudulent use of these cards in financial transactions. The card internally contains a processor connected to a viewable display powered by a battery where the processor is capable of generating security codes on a periodic basis. The card can generate the security code by encrypting certain data is a way that the card issuer as the same security codes so that when the security code is used in a financial transaction, the card issuer can ascertain whether the transaction is valid and authorized or potentially fraudulent.
[0011] An alternative embodiment for the dynamic generation of security codes, the card processor may call from a memory storage area on the card a security code from a list of encrypted security codes. The security code is then validated using the same methodology as a security code that was generated by firmware running on the processor.
[0012] Dynamically generated security codes typically have a life of a couple of weeks before the security code is changed. To prevent unwanted denials of transactions when the security code is changed, a time period window can be created on the card issuer's network that compares the card security code with the current valid security code stored on the card issuer's server as well as the previous security code in case the transaction was processed over a longer period of time than the life of the dynamically generated security code.
[0013] This may be accomplished by creating a mid-point sliding time window whose size is the length of the time allotted for the life of the security code. When the security code arrives at the card issuer's servers, the sliding window is created with the mid-point of the sliding time period window the date of arrival of the card's security code. The sliding time period window may encompass more than one time period representing the life of the card's security code. Therefore, the card issuer's network can analyze all the valid security codes to ascertain whether the correct card security code was assigned at the start of the financial transaction, but was delayed for some reason. This sliding time period window allows for the validation of these slowly processed financial transactions without unduly increasing the risk of fraudulent activity.
[0014] Other systems, methods, features, and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.
DETAILED DESCRIPTION OF THE DRAWINGS
[0015] The components in the figures are not necessarily to scale, emphasis being placed instead upon illustrating the principles of the invention. In the figures, like reference numerals designate corresponding parts throughout the different views.
[0016] FIG. 1 is a side view of a smart, debit or credit card illustrating a flexible display on the rear side of the card.
[0017] FIG. 2 is a block diagram of the hardware in a smart, debit or credit card for enabling the display of a dynamically generated security code.
[0018] FIG. 3 is a block diagram of the data flow when a debit or credit card employing a dynamically generated security code is used to conduct a transaction.
[0019] FIG. 4 illustrates an alternative embodiment using an event based solution where each new security code is generated based on the iteration of an internal counter within the card.
[0020] FIG. 5 is a block diagram of a display code sequence enabling the use of a dynamically generated security code.
[0021] FIG. 6 is a flow chart illustrating the process for card holders who input a PIN to generate a security code.
DETAILED DESCRIPTION
[0022] This invention provides a dynamic allocation of a security code for a smart card, debit card or credit card. In an effort to thwart smart, debit and credit card fraud, this invent provides for the generation of dynamically allocated card security codes calculated by various means. These dynamically allocated security codes may be generated by: (1) a random number that is encoded by encrypting the bank card number, also known as the Primary Account Number (“PAN”), expiration date and service code with encryption keys typically called Card Verification Keys (“CVK”) known only to the card issuing bank or smart card provider; (2) a list of encrypted numbers assigned to a specific card and stored in the card's memory; or (3) periodically wirelessly transmitted from a card issuer's network and stored in a memory area on the card.
[0023] As a way to overcome the shortcomings of a static, printed security code on the front or back of a smart, debit or credit card 100 , this invention, when implemented dynamically generates a new and different security code periodically on a card. On the outside, card 100 looks very similar to today's smart, debit and credit cards in that it has a PAN number, expiration date, name of an individual or company embossed on the front of the card. The card 100 may also have a logo of an issuing bank or organization backing the card. On the rear of the card 100 , a magnetic stripe 102 containing digital data of the card holder and other relevant data may be stored in memory. Also located on the rear of card 100 may be a signature stripe 104 and a hologram 106 to assist merchants in detecting fraudulent cards.
[0024] For the smart, debit or credit card 100 to dynamically generate security codes, a display 108 may be incorporated into the card's structure. For optimum results, this display 108 may be flexible so that it will handle the stresses generated by card use. Typically, the display 108 may show three or four digits, but a card issuer may adopt a larger code display capable of showing more than four digits. A touch sensitive control button 110 may be incorporated into the card 100 so that whenever the touch sensitive control button 110 is selected the security code is shown on the display 108 . This would preserve battery life as the display could be off until the card holder needs to generate the security code. Also, the card may generate a new security code without any action taken on behalf of the card holder based on the passage of a predetermined amount of time (e.g. a week, two weeks, a month, etc.) set by the card issuer.
[0025] FIG. 2 is a block diagram of the hardware that may be used to implement the generation of dynamic security codes in a smart, debit or credit card 200 . The card 200 may comprise a built in microprocessor/controller 202 , battery 204 , memory storage area 206 which may be located within the microprocessor or external of the microprocessor/controller 202 , and a flexible display 208 . The flexable display 208 may be constructed using an e-paper type display so that the flexible display 208 is always on and a security code is always visible to the card holder when examined.
[0026] Additional hardware features may include an in internal Radio Frequency (“RF”) antenna 210 , a touch keypad 212 , an internal clock (not shown) and a touch sensitive control button 214 . Typically, smart cards, debit cards and credit cards are manufactured by one vendor and sent to another vendor for imprinting the PAN number, card holder name and expiration date of the card 200 . The uploading of the security codes maybe be accomplished by the card issuer or the vendor charged with imprinting the PAN number, card holder name and expiration date with a contact or contactless smart card chip or through the use of a built in RF antenna 210 . The RF antenna 210 may utilized as methodology to increase the productivity of the vendor generating the cards for the cardholder. The RF antenna 2010 may be used to download updated firmware for the processor 202 ; download updated algorithms for calculating the security codes; resynchronize the card with the card issuer's network or download an updated list of security codes sent by the card issuer's network into the memory 206 . These downloads may occur when the card is made and assigned to the cardholder. These downloads may also be accomplished after the card is in the possession of the card holder.
[0027] Many card issuer networks are developing standards for the financial industry. EMV stands for the Europay, Master Card and Visa global standard for the interoperation of Integrated Circuit Cards (“IC Cards”) and IC Card point of sale terminals and Automated Teller Machines (“ATMs”) for authenticating smart, debit and credit card transactions. With the adoption of IC Cars in Europe and the planned roll out of IC Cards in the United States and other countries in the coming years, the dynamic generation of security codes may be easily implemented. When the card holder inserts their card into a IC Card point of sale terminal or inserts their IC Card into an ATM, the card with the dynamically generated security code could automatically generate a new security code after the IC Card completes the transaction. Such an implementation could produce a time and event combination where the card dynamically generates a new security code after a predetermined time period has elapsed and where the card dynamically generates a new security code after a specific event occurs such as when the IC Card is inserted into an IC Card point of sale terminal or ATM.
[0028] Protecting the security codes inside the card 200 is important for the overall card system security's interface with the transaction processing network as shown in FIG. 3 . Regardless of whether the security codes are calculated by the card 200 or generated when the card 200 is produced and stored into memory pulled out from a list, the security codes should be encrypted to prevent thieves from accessing the internal working hardware and deciphering the securities codes and algorithm. When the security code is calculated, a cryptography key is at risk and should be protected. Also, a listing of keys that are stored in the card's memory should also be encrypted. Once the security code has been generated or recalled from the card's memory, it is displayed on the card 200 and it is no longer a secret anymore. However, the security code that is generated will have a limited life and will only be valid for a predetermined time period.
[0029] The addition of a touch sensitive control button 214 generates a signal within the card 200 indicating that the card holder desires a security code and the card generates and shows the security code in the display 208 . The use of such a touch sensitive control button 214 would extend the battery life of the card 200 and would only energize or light up the display 208 specifically when the user seeks to use the card 200 . The implementation of a key pad 212 could provide additional security requiring the card holder to insert a PIN on the key pad 212 before the security code is shown on the display 208 . An additional security level could be added with the use of a key pad 212 by allowing the secure code algorithm to generate a correct security code when the correct PIN is input on the key pad 212 and the generation of an incorrect security code if an incorrect PIN is input on the key pad 212 .
[0030] Another security enhancing feature could be the addition of a One Time Password (“OTP”) that would be delivered to the user via a text message sent to the card holder's mobile device for access to online banking. The OTP would not necessarily replace the user's password, but could be required as a third component (login name, password and security code). Since the card only has one display of typically 3 or 4 digits, the OTP could work whenever the user requires an OTP to be generated. When requested, a user would press on the touch sensitive control button 214 of the card 200 and a new OTP would be displayed on the display 208 for a limited time (e.g. 30 seconds or less). Once the OTP code was viewed for the predetermined time period, the security code would replace permanently the OTP on the display 208 . Pressing the touch sensitive control button 214 a second time would generate another OTP and so on. Each OTP would be valid for a limited time or based on a counter.
[0031] Another embodiment may include the implementation of two distinct functions on the same card (e.g. distinct crypto keys for different functions). In the case of a two feature card such as the implementation of an OTP and a dynamically generated security code, two different crypto algorithms may be implemented or one algorithm for the OTP calculation and a list of security codes for the dynamically generated security code implemented with two separate crypto keys for each function. Therefore, it would be possible for a bank or card issuer to split the security responsibilities between two distinct departments such as online banking and payment processing.
[0032] As a way to ensure that a card holder does not mix up the OTP and dynamically generated security code, a solution could be implemented where the OTP utilizes a four digit code and the dynamically generated security code is shown with three digits. Every time a card holder pressed the touch sensitive control button 214 , the card holder would see the four digits OTP displayed for predetermined amount of time, e.g. 30 seconds followed by the display the 3 digits dynamically generated security code.
[0033] The dynamic generation of security codes may be calculated or called from a list of security codes stored in the memory location 206 on the card 200 . An alternative embodiment may allow for the transmission of a unique security code to a card holder's mobile device that is then input into the card via the key pad 212 . These solutions present several implementation issues such as (1) how long the security code should be valid; (2) how the card will be authenticated by the card issuer or payment processor with the dynamically generated or recall of the security code from a list of codes stored in the card's memory; and (3) compliance with a variety of card use transaction scenarios such as online, mail order, multi suppliers' orders, fax processed orders, un-synchronized transactions and etc.
[0034] FIG. 3 is a block diagram of a card of the data flow when a debit or credit card employing a dynamically generated security code is used to conduct a transaction. When an online or phone transaction 300 is attempted by a card holder, the card information, expiration date, cardholder's name and security code is transmitted to the merchant or organization processing a payment 302 . In other transaction scenarios, a card holder may process a transaction that requires a significant amount of time. Such time consuming transactions include those transactions conducted by fax or mail 304 . Once the merchant 302 receives the card's data, the card number and zip code are typically verified with the payment processor 306 . In some instances the payment processor may be asked to perform the security code authorization such that the payment processor has the capability of authenticating the validity of the card security code.
[0035] The payment processor 306 then compares the card holder to a list of banned cards and if a match is not made the payment processor 306 passes the card data to the card networks such as Visa, Master Card, American Express, Discover, Europay Maestro, etc. 308 and 310 . This card data is then routed to the appropriate network. For example, Visa cards are routed to the Visa network 308 and the Master Cards care routed to the Master Card network 310 . Likewise, American Express cards and Europay cards are routed to their respective networks. These card networks 308 and 310 provide security code authorization, zip code authorization and debit and credit the banks Please note smaller banks may push zip code authorization to the card networks or even the payment processor 306 . These networks 308 and 310 perform the security code authorization points that are capable of authenticating the validity of the security code as well as interface with various banks 312 to ensure the seamless flow of money and goods when card holders seek to complete transactions.
[0036] The same system applies to the implementation of dynamically generated security codes. Here, the bank may issue a card to a customer where the bank sends card holder information to a card issuer who generates a working smart, debit or credit card to the bank's customer. The security code information may be based on information supplied by the payment processor 306 or the card issuer. The security code validation data is supplied to the payment processor 306 so that transactions can be verified and authenticated by the payment processor 306 or the card issuer's network 308 and 310 .
[0037] A complication that arises in the implementation of a dynamically generated security code is how long the security code should remain valid. If the security code window of validity is limited to several minutes, online and mail order phone transactions have a high probability of success while faxed transactions or transactions accomplished by mail will nearly always fail. Thus, there needs to be a balance between decreasing the potential for fraud activity and optimizing the types of transactions so that the overwhelming majority of card holder transactions are approved. This time window is best optimized for a validity window of one to two weeks. The determination of the optimum time window is typically selected by the card issuer based on their statistical data for card usage and the level of fraud activity.
[0038] FIG. 4 illustrates an alternative embodiment using an event based solution where each new security code is generated based on the iteration of an internal counter within the card. In such an event based implementation, the new security code may be calculated or recalled from a list stored in memory. Each time the user seeks to use the card, the card holder will press the touch sensitive control button 400 located on the card. When the touch sensitive control button the card pressed the card generates a first security code 402 . A built in counter within the card increments a starting value by one 404 . When the card holder presses the touch sensitive control button a second time 406 a new security code is generated 408 and displayed on the card 410 . The second security code is then used in the next transaction 412 . The card processor then compares the transmitted security code with the next security code stored in their authorization system 414 . If the security codes match, the transaction is authorized and approved 416 . The card processor's authorization system increments its counter ( 418 ) and waits for the next transaction. If the security codes do not match, the transaction is rejected 420 .
[0039] A problem occurs however when a card holder keeps pressing on the touch sensitive control button or when the card activates by itself based on pressures exerted on a wallet and multiple codes are generated without being submitted as a part of a transaction to the payment processor. When a legitimate transaction is attempted by the card holder a de-synchronization issue will arise between the counter inside the card and the counter located on the backend processing side at the payment processor. This issue may be counteracted by the addition of a large window of possibilities, but when a three digit security codes is implemented the window may become sufficiently large that a person engaged in card fraud may guess a security code based on the average probability thus rending the security features meaningless. Also, if a card were to fall into the hands of a child, repeated pressing of the touch sensitive control button could quickly cause the counter to become de-synchronized. In these scenarios, the card holder's frustration is likely to rise and the card issuers cost rise as cards become frequently replaced well before their intended expiration.
[0040] FIG. 5 is a block diagram of a simple display code sequence enabling the use of a dynamically generated security code. Using a time based implementation methodology where the security code changes by itself based on a periodic clock event, eliminates the de-synchronization possibility based on inadvertent repeated selection of the touch sensitive control button. When the card is initialized by the card issuer, the card and the backend processing system controlled by the payment processor are synchronized. As added protection, a limited time drift window may be implemented to further reduce potential problems ensuring that the security codes are not out of synchronization. Also, the addition of a time drift solution could eliminate the need for a card holder to select the touch sensitive control button 214 on the card, since the security code could change itself automatically based on input from the internal clock. The only limitation on this solution would be the battery life with the display always on.
[0041] A time based methodology for the generation of security codes typically requires the card to have an internal clock or wireless access to a time keeping system so that the generation of security codes are synchronized with the card issuer or payment processor. As an alternative, the card could connect to the payment processor or a third party who maintains a clock for synchronization timing solutions. With a sufficiently long period of time window to deal with transactions that require a longer period of time, e.g. faxed or mail transactions, one security code could be used for multiple transactions that may occur during this time period window.
[0042] For the time window, a solution is to have a card capable of generating a new security code that is valid during a periodic time window that is sufficiently large enough to overcome delays that may exist in transactions that require more time, e.g. fax and mail transactions. A typical time window could be as short as one week or as long as one month. In other words, a specific security code will be valid for a fixed period of time and the same security code will be displayed on the card. When the time window expires the card will dynamically generate a new code or recall from memory the next security code from a list of security codes stored on the card. As an alternative embodiment for storing a list of security codes on the card, this list may be stored in the cloud on the card issuer's servers or card processor's servers and called by wireless commands automatically sent from the card to these servers without the card holder knowing that these communication messages are being sent and received by the card. However, a major limitation for such a wireless interface with the cloud is for card holders who may be attempting to conduct a transaction in a remote location where wireless connections are not possible thus when it is time for the card holder to conduct a transaction, no current security code is stored on the card.
[0043] Referring to FIG. 5 , whenever a request for a security code is submitted by the card holder by pressing the touch sensitive control button 214 to the processor, a calculation is performed or the security code is recalled from a security code list stored in the memory on the card 200 based on the time period window 500 . The card that is enabled to dynamically generate a security code 502 tracks the various time period windows Period 1 ( 504 ), Period 2 ( 506 ) and Period 3 ( 508 ). The security codes that will be generated for each of the time period windows Period 1 ( 404 ), Period 2 ( 406 ) and Period 3 ( 508 ) are 111 ( 510 ), 222 ( 512 ) and 333 ( 514 ) respectively.
[0044] The security code 111 ( 510 ) is generated by the card 502 and sent to the card issuer or payment processor authorization system 516 . The card issuer or payment processor card authorization system 516 compares the card's security code 111 ( 510 ) to the security code authorized by the card issuer or payment processor's computer systems 516 . If the security codes match, the transaction proceeds accordingly and payment is made. Otherwise, payment authorization is declined.
[0045] In order to prevent valid codes from being rejected by the card issuer or the payment processor authorization system 516 , when a transaction is attempted by a card holder that is close to or just past the time period window for the security code's validity, the card issuer or payment processor authorization system 516 may consider the security code 111 ( 510 ) entered by the card holder 502 was sent during the middle of the sliding time period window 518 .
[0046] Also, the sliding time period window 518 may allow the authorization of multiple values 111 ( 520 ) and 222 ( 522 ) allowing for various types of transactions by the card holder ranging from fast e-commerce transaction to transactions taking days or a couple of weeks such as those conducted by mail. For example, if a time period window is considered valid for fifteen (15) days and a security code is submitted on the fourteenth (14 th ) day, the card issuer or payment processor authorization system 416 may match the submitted security code 111 ( 510 ) against a first security code 111 ( 520 ) that is seven (7) days old and second security code 222 ( 522 ) that is seven (7) days in the future. Therefore, this security code matching methodology allows time period window flexibility for slower transactions such as those attempted by fax or mail without increasing otherwise valid transactions from being declined.
[0047] A likely scenario is that the time periods between the dynamic generation of security codes will vary between differing card issuer networks. Also, the sliding time period window will also likely differ between the various card issuer networks.
[0048] FIG. 6 is a flow chart illustrating the process for card holders who may have to input a PIN or password to generate a security code. When the card holder seeks to obtain a security code 600 , the card may or may not require the input of a PIN or password 602 . If the card requires the card holder to input a PIN or password 604 , the card tests with whether the correct PIN or password was input 606 . If the PIN or password was not correctly input, the card holder inputs the PIN or password again 604 . If the PIN or password was correctly input, the security code is generated by the card 608 . The PIN or password may be generated by the card issuer's network and transmitted to a card holder's mobile device as a text or email message.
[0049] The security code is then transmitted as one of the required values (e.g., card number, card holder name and expiration date) to the card processor 610 . The security code is then analyzed by the card processor and compared with the security code for the time period window 612 . If the card security code matches security code in the card processor's authentication system, then the transaction is authorized and approved 614 . If the security code that was not submitted in the current time period window 612 the card processor determines whether the security code submitted was in the next time period window 616 . If the security codes match, then the transaction is authorized and approved 614 . If the security codes do not match, then the transaction is rejected 618 .
[0050] While various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of this invention. | This invention provides a dynamically generated security code for smart, debit and credit cards as a way to thwart fraudulent use of these cards in financial transactions. The card internally contains a processor connected to a viewable display powered by a battery where the processor is capable of generating security codes on a periodic basis. The card can generate the security code by encrypting certain data is a way that the card issuer as the same security codes so that when the security code is used in a financial transaction, the card issuer can ascertain whether the transaction is valid and authorized or potentially fraudulent. To prevent unwanted denials of transactions when the security code is changed, a time period window can be created on the card issuer's network that compares the card security code with the current valid security code stored on the card issuer's server as well as the previous security code in case the transaction was processed over a longer period of time than the life of the dynamically generated security code. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a sheet transport apparatus for use in a printer, a facsimile machine and, more particularly, an ink jet type image forming apparatus.
2. Description of the Related Art
An ordinary, conventional ink jet recording apparatus will be described with reference to FIGS. 12 and 13. FIG. 12 shows a recording head 101 for recording by ejecting ink, a carriage 102 capable of moving while supporting the recording head 101, guide rails 103 for supporting and guiding the carriage 102, a motor 104 for driving the carriage 102, a pulley 105 directly connected to the motor 104, a follower pulley 106 opposite to the pulley 105, a wire 107 wrapped around the pulley 105 and the follower pulley 106 to transmit motive power of the motor 104 to the carriage 102, a recording medium 109, such as paper, a paper feed motor 110 for moving the recording medium 109, a cap 112 for protecting nozzles from drying and other problems, a transport roller 115 for transporting the recording medium 109, a pressing roller 116 for pressing the recording medium 109 against the roller 115 by using an urging means (not shown), and a non-recording ejection box 117 positioned between the cap 112 and the recording medium 109 and used for receiving ejection of ink droplets from the recording head 101 other than ejection for recording. The carriage 102 is movable in the directions of arrows 113, and the roller 115 is rotated in the direction of arrow 114.
When recording is performed by this apparatus, the recording head 101, having the nozzles protected by the cap 112, is moved away from the cap 112, and the motive power from the motor 104 is transmitted to the wire 107 wrapped around the pulley 105 and the follower pulley 106. The recording head 101 is thereby moved together with the carriage 103 parallel to the recording medium 109 and is moved through a predetermined range in the vicinity of the recording medium 109 to scan the same. Thereafter, the direction of movement of the recording head 101 is reversed and the recording head 101 is moved toward the cap 112. During this scan, the recording head 101 ejects ink droplets at predetermined positions to perform recording while traveling back and forth in the directions of arrows 113. Each time this cycle of scanning of the recording head 101 on the recording medium 109 is completed, the recording medium 109 is fed through a predetermined distance along the direction of arrow 114 by the paper feed motor 110 and the roller 115. These operations are repeated to perform recording.
However, the above-described conventional recording apparatus has drawbacks described below. In the example of the conventional apparatus shown in FIG. 12, recording cannot be performed on an end portion of the recording medium 109 located between the nip of the transport and pressing rollers 115 and 116 and the nozzle at the end of the head closer to the pressing roller 116 by a final scanning stroke, because there is no means for accurately feeding this portion of the recording medium 109 to the recording position. Therefore, a margin of a recorded page corresponding to such a trailing end portion of the recording medium 109 is large and a suitable image size cannot be obtained.
FIG. 13 illustrates the size of the margin. In particular, if the recording medium 109 has a certain large size such as A1 or A0 size, then the pressing roller 116, the length of which is correspondingly large, must have an increased diameter in order to maintain its desired strength, resulting in a further increase in the size of the margin. If a pair of rollers are provided on the downstream side of the recording medium 109, a similar margin is formed at the leading end of the recording medium 109.
A recording apparatus having a similar construction and having pairs of rollers respectively provided on the upstream and downstream sides of the recording medium 109 facing the recording head 101 is also known. In this apparatus, if the feed rates of the pairs of rollers are equal to each other, there is a possibility of the recording medium bending between the pairs of rollers to contact the recording head when feed errors are accumulated. To prevent occurrence of such a phenomenon, the feed rate of the downstream rollers is set so as to be a significant percentage larger than that of the upstream rollers. In this arrangement, however, the recording medium 109 is fed only by the downstream rollers after the trailing end of the recording medium 109 has passed the upstream rollers. Unless the feed rate of the downstream rollers is changed at this time, the accuracy of image formation is reduced. A complicated feed rate control is therefore required for this arrangement.
Water is ordinarily used as a main solvent for recording ink. If an image is recorded at a high density, a large amount of water is applied to the recording medium 109 to permeate into the same, thereby causing the recording medium 109 to swell and increase in size. As a result, a cockling or warping phenomenon occurs such that the recording medium 109 is cockled in the recording area. If the height of cockles thereby formed is increased, it is possible that the recording medium 109 will contact the head 101 to cause a disturbance in the resulting image or that clogging will occur in the nozzles of the recording head 101.
SUMMARY OF THE INVENTION
In view of the above-described technical problems of the conventional sheet transport apparatus having rollers, an object of the present invention is to provide a sheet transport apparatus in which the amount of deformation of a recording medium sheet can be limited to a small value.
Another object of the present invention is to provide a sheet transport apparatus in which a drive load caused upon a transport belt due to an electrostatic attraction force between the transport belt and an electrostatic attraction force generation means can be markedly reduced.
To achieve these objects, according to one aspect of the present invention, there is provided a sheet transport apparatus comprising a transport belt for transporting a sheet member by contacting the sheet member, and electrostatic attraction force generation means for generating an electrostatic force for attracting the sheet member to a surface of the transport belt, the electrostatic attraction force generation means being disposed close to another surface of the transport belt opposite to the surface brought into contact with the sheet member. At least one of a surface of the electrostatic attraction force generation means contacting the transport belt and a surface of the transport belt contacting the electrostatic attraction force generation means is roughened.
According to another aspect of the present invention, there is provided a sheet transport apparatus comprising a transport belt for transporting a sheet member by contacting the sheet member, and electrostatic attraction force generation means for generating an electrostatic force for attracting the sheet member to a surface of the transport belt. The electrostatic attraction force generation means is disposed close to another surface of the transport belt opposite to the surface to be brought into contact with the sheet member. An electrostatic attraction force generated at at least one particular portion of the transport belt, of the electrostatic attraction force generated on the transport belt by the electrostatic attraction force generation means, is smaller than an electrostatic attraction force generated at the other portion of the transport belt.
According to yet another aspect of the present invention, there is provided a sheet transport apparatus comprising a transport belt, an electrostatic attraction force generation means, and reducing means. The transport belt transports a sheet member and has an inner surface and an outer surface. The sheet member contacts the outer surface. The electrostatic attraction force generation means generates an electrostatic force for attracting the sheet member to the outer surface of the transport belt. The electrostatic attraction force generation means is disposed adjacent the inner surface of the transport belt. The reducing means reduces a load between the inner surface of the transport belt and the electrostatic attraction force generation means.
These and other objects and features of the present invention will be come apparent from the following detailed description of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic longitudinal sectional side view of the overall construction of an ink jet printer to which the present invention is applied;
FIG. 2 is a schematic longitudinal sectional side view of the overall construction of a sheet transport apparatus provided in the printer shown in FIG. 1;
FIG. 3 is a partially-cutaway perspective view of the overall construction of the sheet transport apparatus shown in FIG. 2;
FIG. 4 is a longitudinal sectional side view of the overall construction of a sheet transport apparatus in accordance with a first embodiment of the present invention;
FIG. 5 is a schematic longitudinal sectional side view of the overall construction of a sheet transport apparatus in accordance with a second embodiment of the present invention;
FIG. 6 is a schematic longitudinal sectional side view of the overall construction of a sheet transport apparatus in accordance with a third embodiment of the present invention;
FIG. 7 is a partially-cutaway perspective view of the overall construction of the sheet transport apparatus shown in FIG. 6;
FIG. 8 is a partially-cutaway perspective view of the overall construction of a belt charging unit provided in a sheet transport apparatus in accordance with a fourth embodiment of the present invention;
FIG. 9 is a schematic longitudinal sectional side view of the overall construction of a sheet transport apparatus in accordance with a fifth embodiment of the present invention;
FIG. 10 is a schematic longitudinal sectional side view of the overall construction of a sheet transport apparatus in accordance with a sixth embodiment of the present invention;
FIG. 11 is a schematic plan view of an essential portion of a belt charging unit provided in a sheet transport apparatus in accordance with a seventh embodiment of the present invention;
FIG. 12 is a perspective view of essential components of a conventional ink jet recording apparatus; and
FIG. 13 is a diagram showing a margin on a recording medium in the conventional recording apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows the overall construction of an ink jet printer as an example of an apparatus to which the present invention is applied.
The overall construction of this printer will be described along the flow of sheet members.
This printer has a feed cassette 2 detachably set in a printer body 1, and a retractable feed tray 3 provided on a side portion of the printer body 1. Sheet members are selectively fed from one of these feed units.
Sheet members stacked in the feed cassette 2 are fed out one after another from the uppermost one by a feed roller 4 which is rotated clockwise. Each sheet fed out by the feed roller 4 travels in the direction of arrow A while being guided by guides 5 and 6.
Sheet members stacked on the feed tray 3 are fed out one after another from the uppermost one by a feed roller 7 which is rotated counterclockwise. Each sheet fed out by the feed roller 7 travels in the direction of arrow A while being guided by guides 5 and 6.
Thereafter, the sheet member is transported onto an endless transport belt 9, which is rotated clockwise, by a transport roller 8 rotating counterclockwise. The sheet member is carried on the transport belt 9 to be transported to a position below an ink jet type printing head 10. Predetermined printing is performed on the sheet surface with inks selectively ejected from a plurality of nozzles of the printing head 10.
The endless transport belt 9 is formed of a sheet of a synthetic resin (e.g., polycarbonate, polyethylene or the like) having a thickness of about 0.1 to 0.2 mm. The endless transport belt 9 is wrapped around a driving roller 11 disposed on the downstream side of the printing head 10 and a follower roller 12 disposed on the upstream side of the printing head 10, and a suitable tension is caused in the belt 9 by a tension roller 13.
The endless transport belt 9 thus formed has a horizontal portion 9A between a center of the driving roller 11 and a center of the follower roller 12. Each sheet member is transported by the horizontal portion 9A. The transport roller 8 is disposed so as to face the follower roller 12 and contacts the transport belt 9 at a predetermined pressure.
The endless transport belt 9, rotated clockwise by the rotational driving of the driving roller 11, is charged by an electrostatic attraction force generation unit (electrostatic attraction force generation means) 14 provided under the horizontal portion 9A so as to be ready to attract each sheet member. Therefore, the sheet member placed on the transport belt 9 by the transport roller 8 is transported in a state of being attracted by an electrostatic force to the transport belt 9.
Since the sheet member transported by the transport belt 9 is electrostatically attracted to the transport belt 9 in this manner, floating of the sheet member on the printing head 10 side is prevented during transport, and it is therefore possible to limit cockling due to ink ejected from the printing head 10.
After the completion of printing on the sheet member by the printing head 10, the sheet member is transported to the pair of downstream discharge rollers 15 by the transport belt 9 and is discharged onto a discharge tray 16 in a slanted attitude by the pair of discharge rollers 15.
The printing head 10 and an ink tank 17 for supplying ink to the printing head 10 are held on a main scanning carriage 18 which can be moved in a direction perpendicular to the sheet transporting direction (perpendicular to paper).
The main scanning carriage 18 is moved in a direction perpendicular to the sheet transporting direction along a rail 19 in the form of a round rod fitted in the main scanning carriage 18 and along a rail 21 which guides rollers 20 provided on the main scanning carriage 18.
The printing operation of the printing head 10 will not be described in this specification.
FIGS. 2 and 3 show the construction of the electrostatic attraction force generation unit 14 for electrostatically attracting the transport belt 9.
The electrostatic attraction force generation unit 14 has an electrode base 14A, a comb-like electrode plate 14B, a comb-like earth (ground) plate 14C, and an electrode protection member 14D. The comb-like electrode plate 14B and the comb-like earth plate 14C are fixed by an adhesive or the like in a recess 14E formed in an upper surface of the electrode base 14A in a state of meshing with each other with a certain spacing maintained therebetween. Tooth-like portions of the electrode plate 14B and the earth plate 14C extend along the sheet transporting direction.
The electrode protection member 14D is formed of a sheet of a synthetic resin (e.g., polycarbonate, polyethylene or the like) having a thickness of about 0.1 to 0.2 mm, and is fixed on the electrode base 14A by an adhesive or the like so as to cover the electrode plate 14B and the earth plate 14C.
The electrode protection member 14D contacts the endless belt 9 and also contacts the electrode plate 14B and the earth plate 14C. The surfaces of the electrode protection member 14D and the transport belt 9 are smoothly formed.
When a predetermined voltage (e.g., 0.5 to 10 kV) is applied to the electrode plate 14B of the electrostatic attraction force generation unit 14, the transport belt 9 is charged through the electrode protection member 14D to generate an electrostatic attraction force applied to the horizontal portion 9A of the transport belt 9. The earth plate 14C is grounded. Alternatively, a voltage having a polarity opposite to that of the voltage applied to the electrode plate 14B may be applied to the earth plate 14C. This electrostatic attraction force is generated uniformly in magnitude through an upstream end region a located on the upstream side of the printing head 10, a printing region b facing the printing head 10, and a downstream region c located on the downstream side of the printing head 10.
The upstream region a, where the electrostatic attraction force is generated, is provided to prevent slippage between the sheet member S and the transport belt 9 through a length of transport passage from the transport roller 8 disposed in such a position as to avoid interference with the main scanning carriage 18 to the printing head 10.
The downstream region c, where the electrostatic attraction force is generated, is provided to enable the sheet member S to smoothly enter the nip between the pair of discharge rollers 15 without floating.
The above-described sheet transport apparatus (composed of the transport belt 9 and the electrostatic attraction force generation unit 14 and other components) provided in the printer basically entails a problem described below. That is, when an electrostatic attraction force is generated on the transport belt 9 by the electrostatic attraction force generation unit 14, an electrostatic attraction force is also caused between the transport belt 9 and the electrode protection member 14D. The transport belt 9 rotated clockwise is thereby attracted to the electrode protection member 14D to cause a drive load (frictional resistance) on the transport belt 9. This problem is negligible when the drive load is small.
However, if both the electrode protection member 14D and the transport belt 9 are formed so as to contact each other by their smooth surfaces, they closely contact each other by an electrostatic attraction force, so that the drive load on the transport belt 9 is considerably large.
In the case where an electrostatic attraction force is also generated at the upstream region a and the downstream region c at the same magnitude as that generated at the printing region b, the total electrostatic attraction force generated between the transport belt 9 and the electrode protection member 14D through the entire length of the belt charging unit 14 is substantially large. Accordingly, the drive load on the transport belt 9 in this case is considerably large. Essentially, at the upstream or downstream region a or c, a small electrostatic attraction force enough to prevent the sheet member S from slipping or floating will suffice.
If the drive load on the transport belt 9 is considerably increased for the above-described reason, it is necessary to drive the transport belt 9 by a motor having a large torque matching the drive load. Also, a slippage may occur between the driving roller 11 and the transport belt 9 to reduce the accuracy with which the sheet member S is fed.
According to the present invention, therefore, an arrangement described below is adopted.
In the sheet transport apparatus of this embodiment, as shown in FIG. 4, the entire upper surface of the electrode protection member 14D in contact with the transport belt 9 is finely roughened as indicated at 30 in FIG. 4 to form a fine roughness pattern in which the average distance between peaks is several microns to several tens of microns. The fine roughness pattern 30 is a crease-like pattern in which grooves or projections extend generally perpendicularly to the sheet transporting direction, a diagonal pattern, or the like. The fine roughness pattern 30 is formed, for example, by etching, sand blasting or embossing. The difference in level between peaks and troughs in the roughness pattern is several microns to several tens of microns.
FIG. 5 shows the overall construction of a sheet transport apparatus in accordance with the second embodiment of the present invention.
In this sheet transport apparatus, a fine roughness pattern 31 having a peak or trough pitch of several microns to several tens of microns is formed on the inner surface of the transport belt 9 in contact with the electrode protection member 14D. The configuration of this fine roughness pattern 31 and the method of forming this pattern are the same as in the case of the fine roughness pattern 30 of the first embodiment of the present invention.
The fine roughness pattern 30 may be formed on the electrode protection member 14D in addition to the fine roughness pattern 31 formed on the transport belt 9.
FIGS. 6 and 7 show the overall construction of a sheet transport apparatus in accordance with the third embodiment of the present invention.
In this sheet transport apparatus, to vary the electrostatic attraction force, which is proportional to the electrode area, portions 32 and 33 (electrostatic attraction force reduction means) of the comb-like electrode plate 14B and the comb-like earth plate 14C corresponding to the upstream region a and the downstream region c (particular portions), respectively, are formed so as to be smaller in width and in area than portions 34 corresponding to the printing region b (other portion).
The electrostatic attraction forces generated at the upstream and downstream regions a and c are thereby reduced relative to the electrostatic attraction force generated at the printing region b.
The electrostatic attraction force generated at the printing region b is set to a magnitude such that the sheet member S can closely contact the transport belt without causing any printing failure, while each of the electrostatic attraction forces generated at the upstream and downstream regions a and c is set to a magnitude large enough to prevent a slippage or floating of the sheet member S.
FIG. 8 shows the overall construction of an electrostatic attraction force generation unit provided in a sheet transport apparatus in accordance with the fourth embodiment of the present invention.
In this sheet transport apparatus, the electrode protection member 14D is formed of a part 35 corresponding to the upstream area a, a part 36 corresponding to the printing area b and a part 37 corresponding to the downstream area c. The volume resistivity of the part 36 corresponding to the printing area b is reduced relative to those of the parts 35 and 37 corresponding to the upstream and downstream regions a and c (particular portions).
The electrostatic attraction forces generated at the upstream and downstream regions a and c are thereby reduced relative to the electrostatic attraction force generated at the printing region b.
In this embodiment, the electrode protection member 14D is divided into three parts 35, 36 and 37 differing in volume resistivity. Alternatively, the volume resistivity of one electrode protection member 14D may be varied with respect to portions corresponding to the regions a, b, and c.
FIG. 9 shows the overall construction of a sheet transport apparatus in accordance with the fifth embodiment of the present invention.
In this sheet transport apparatus, recesses 38 and 39 (electrostatic attraction force reduction means) are formed in the upper surface portions of the electrode protection member 14D corresponding to the upstream and downstream regions a and c (particular portions). The recesses 38 and 39 form air layers.
The electrostatic attraction forces generated at the upstream and downstream regions a and c are thereby reduced relative to the electrostatic attraction force generated at the printing region b.
FIG. 10 shows the overall construction of a sheet transport apparatus in accordance with the sixth embodiment of the present invention.
In this sheet transport apparatus, fine roughness patterns 40 and 41 (electrostatic attraction force reduction means) having a peak or trough pitch of several microns to several tens of microns are formed in the entire upper surface portions of the electrode protection member 14D corresponding to the upstream and downstream regions a and c (particular portions). The configuration of these fine roughness patterns 40 and 41 and the method of forming these patterns are the same as in the case of the fine roughness pattern 30 of the first embodiment of the present invention.
The electrostatic attraction forces generated at the upstream and downstream regions a and c are thereby reduced relative to the electrostatic attraction force generated at the printing region b.
FIG. 11 shows the construction of an essential portion of an electrostatic attraction force generation unit provided in a sheet transport apparatus in accordance with the seventh embodiment.
Portions 42 (electrostatic attraction force reduction means) of the comb-like electrode plate 14B and the comb-like earth plate 14C corresponding to a sheet center passage region e (particular portion) along which a central portion of the sheet member passes are formed so as to be smaller in width and in area than portions 43 and 44 corresponding to sheet end passage regions d and f (other portion) along which left and right end portions of the sheet member pass.
In FIG. 11, a symbol S1 designates an A4 size sheet member while a symbol S2 designates an A5 size sheet member.
The electrostatic attraction force generated at the sheet center passage region e of the transport belt is thereby reduced relative to the electrostatic attraction forces generated at the sheet end passage regions d and f.
In this embodiment, the electrostatic attraction force at the sheet center passage region e of the transport belt is reduced while the electrostatic attraction forces at the sheet end passage regions d and f are substantially large. This arrangement may be adopted in combination with any of the arrangements of the second, third and fourth embodiments.
In the ink jet head used in accordance with the above-described embodiments, heating elements are provided in the nozzles for ejecting ink. A bubble is formed in ink by thermal energy generated by each heating element, and an ink droplet is jetted through the nozzle by the expansion of the bubble.
In the sheet transport apparatus of the present invention, as described above, the area of contact between the transport belt and the belt charging means electrostatically attracted to each other is reduced as well as the adherence therebetween, thereby achieving a reduction in the drive load on the transport belt caused by the electrostatic attraction.
Also, a region of a small electrostatic attraction force is provided between the transport belt and the belt charging means electrostatically attracted to each other, thereby also achieving a reduction in the drive load on the transport belt caused by the electrostatic attraction.
The individual components shown in outline in the drawings are all well-known in the image recording and sheet transporting arts and their specific construction and operation are not critical to the operation or best mode for carrying out the invention.
While the present invention has been described with respect to what are currently considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. | A sheet transport apparatus includes a device for generating an electrostatic attraction force for attracting a sheet member to a surface of a transport belt disposed close to another surface of the transport belt opposite to the surface that contacts the sheet member. The apparatus is arranged to reduce a drive load on the transport belt caused by the electrostatic attraction force. To achieve this effect, at least one of a surface of the electrostatic attraction force generating device contacting the transport belt and a surface of the transport belt contacting the electrostatic attraction force generating device is roughened. Alternatively, an electrostatic attraction force generated at at least one particular portion of the transport belt by the electrostatic attraction force generating device is smaller than an electrostatic attraction force generated at another portion of the transport belt. | 1 |
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
BACKGROUND OF THE INVENTION
The present invention relates generally to optical guidance systems for providing visual cues of glide slope location to aircraft, and more particularly to a novel portable landing aid for providing glide slope information to aircraft under adverse lighting conditions at austere landing sites.
The present invention provides a portable glide slope indicator including a pair of light sources, one projecting a steady beam and one projecting a blinking beam. A pair of indicators deployed at the end of a runway provide accurate and easily interpretable visual glide slope information, whereby the pilot of an incoming aircraft may easily determine the position of the aircraft relative to a preselected glide path. The glide slope indicator of the invention may include filters to project infrared light beams observable with night vision aids. The indicator has particular utility for assisting aircraft landings on austere runways at night with or without infrared night vision assistance.
It is, therefore, a principal object of the invention to provide an improved aircraft glide slope indicator.
It is a further object of the invention to provide a portable glide slope indicator system for beaming visual glide slope information to aircraft.
It is yet another object of the invention to provide a glide slope indicator system for visually defining glide path location observable with infrared sensitive vision aids for night landings.
It is yet another object of the invention to provide a portable glide slope indicator system to facilitate aircraft landings on austere landing sites.
These and other objects of the present invention will become apparent as the detailed description of certain representative embodiments thereof proceeds.
SUMMARY OF THE INVENTION
In accordance with the foregoing principles and objects of the present invention, an improved glide slope indicator system for facilitating aircraft landings under adverse lighting conditions on remote or austere landing sites is provided which comprises a pair of indicators deployable near ground level on each side of a runway, each indicator including a housing having an optical window and a pair of light sources mounted in predetermined spaced relationship to each other and to the optical window and connected to a power source and related circuitry to project a well defined first blinking and second steady light beam of predetermined angular divergence and overlap, one indicator disposed to project beams with an overlap elevated at a first angle relative to horizontal and the other indicator disposed to project beams with an overlap elevated at a second angle relative to horizontal different from the first, with a preselected glide path lying between the two overlaps. An infrared filter may be included in each indicator to project beams observable only with infrared sensitive viewing aids. The system may be battery powered for portability.
DESCRIPTION OF THE DRAWINGS
The present invention will be more clearly understood from the following detailed description of representative embodiments thereof read in conjunction with the accompanying drawings wherein:
FIG. 1 is a schematic side view in axial section of a glide slope indicator of the present invention;
FIG. 2 is a side view of an indicator of FIG. 1 supported on a representative mounting structure to elevate the indicator at preselected angle;
FIG. 3 is a schematic perspective view of the end of a runway with a pair of indicators in place, including legends to illustrate the principle of operation of the indicator system of the invention;
FIG. 4 is a view along line D--D of FIG. 3 showing the position of a glide slope relative to the beams projected by each indicator; and
FIG. 5 is a view along line E--E of FIG. 4 illustrating a pilot's view of a pair of indicators during a landing approach.
DETAILED DESCRIPTION
Referring now to FIG. 1 of the drawings, shown therein is a side view in section of an indicator 10 of the present invention. Indicator 10 comprises a housing 11 of predetermined size and shape defining an interior chamber 12, and means defining an optical window, aperture or other optical opening 13 of predetermined height and width at a first end thereof through which a pair of light beams (one blinking and one steady) are projected as hereinafter described. A pair of light sources such as incandescent bulbs 14,15 are mounted within housing 11 near the second end substantially as shown in FIG. 1 and installed in receptacles 16,17 operatively connected to a blinking circuit 18 and to a suitable source of power, such as portable battery pack 19 or the like, which may be integral with or separately attachable to circuit 18 and housing 11.
Bulbs 14,15 are fixedly supported by suitable means within housing 11 in spaced relationship to each other, substantially as shown in FIG. 1, so that the light emitted by bulb 14 is spatially defined by opening 13 as a beam of light B of predetermined vertical and horizontal angular divergences such as that schematically represented in the vertical plane between broken lines 21,22 drawn from the filament of bulb 14 through the respective edges of housing 11 defining opening 13. Similarly, a beam of light S emitted by bulb 15 is defined in the vertical plane between broken lines 23,24 drawn from the filament of bulb 15 to the edges of opening 13. The intensity of bulbs 14,15 is selected depending upon the intended range of visibility of indicator 10.
Housing 11 and opening 13 therein are sized and configured and the positions of bulbs 14,15 within housing 11 and the spacing between bulbs 14,15 are selected (corresponding to the size of opening 13) to project beams B,S having respective predetermined angular divergences b,s in the vertical plane. Width of opening 13 is selected to provide desirable horizontal beam divergence defining an azimuthal sector in which beams B,S are observable. Intensity of bulbs 14,15 may be selected depending on the range of visibility intended for indicator 10. The various components of indicator 10 are preferably sized and arranged so that the upper limit of beam B defined by broken line 21 is substantially parallel to the bottom limit of beam S defined by broken line 24, and the fixed overlap O of beams B,S defined between lines 21,24 is of predetermined (preferably minimal) size defined substantially by the vertical dimension (O) of opening 13 in housing 11.
In order to project a pair of beam B,S having optimum definition, bulbs 14,15 may preferably be housed within respective chambers 26,27 defined within housing 11 by partitions 28,29 to isolate bulbs 14,15 from each other to avoid interference between light emitted from the two bulbs. Partition 29 accordingly includes a pair of apertures 31,32 of appropriate size which, in cooperation with optical opening 13 define beams B,S. A light baffle 33 may be included within housing 11 along the interior surface thereof, substantially as shown in FIG. 1, to block specular light reflection from the interior housing 11 surfaces. Further, the interior surfaces 12a of housing 11 defining chamber 12 may comprise a coated or painted layer of light absorbing material, such as flat black paint, black felt, black velvet, or the like. Housing 11 may comprise any suitable material of construction such as plastic, steel, aluminum, or composite, and may be of any suitable size for the purposes herein described. It is, however, preferable that the weight and dimensions of indicator 10 be minimized for the purpose of portability, consistent with the accomplishment of those purposes. Accordingly, an indicator 10 built in demonstration of the invention comprised a housing 11 of aluminum with overall dimensions of about 4×6×8 inches, including a spacing between bulbs 14,15 of one inch, and an opening 13 one inch high by 1.5 inches wide which provided beams B,S having an overlap in the vertical plane of about one inch.
It may be desirable for beams B,S to be detectable only using selected vision aids, such as infrared sensitive night vision goggles. Accordingly, infrared filter 34 may be included within housing 11 near opening 13, substantially as shown in FIG. 1.
Blinking and power supply circuit 18 may comprise any suitable circuitry apparent to one with skill in the applicable art which may be used to power bulbs 14,15 and to cause one of the bulbs to blink at a predetermined controllable rate, the embodiment depicted herein arranged for bulb 14 to emit a blinking (B) beam and bulb 15 to emit a steady (S) beam. Circuit 18 construction is therefore not limiting of the invention herein, and should provide a blinking frequency to bulb 14 at a moderate predetermined frequency. For optimum visibility of the blinking of beam B, the frequency may preferably be in the range of about 1/2 to 2 Hz although such frequency range is not limiting of the invention herein. In a unit built and successfully tested in demonstration of the invention, a frequency of 1.0 Hz was used.
Referring now to FIG. 2, shown therein is a schematic side elevational view of an indicator 10 of the present invention supported on a representative mounting for projecting beams B,S at a preselected angle. A base 35 may therefore support a post 36 and leveling table 37 on which indicator 10 is mounted. Base 35 may serve as a housing for battery pack 19. A pair of precision off-set wedges 38a,b may support indicator 10 at the approximate desired angle relative to horizontal between leveling table 37 and an upper clamp 39. Fine positioning adjustments for indicator 10 may be provided by leveling screws 40 on leveling table 37, and circular bubble level 41 mounted above indicator 10 as suggested in FIG. 2.
Referring now to FIG. 3, shown therein is a perspective view of the end of a runway 46 having on either side indicators 10L,10R of the type described above in relation to FIG. 1, whereby a system is defined in accordance with the present invention to provide visual glide slope information to an aircraft. A pair of indicators 10L,10R are therefore placed on the left and right sides, respectively (as viewed from an incoming aircraft), of runway 46 near threshold 47 thereof. Indicators 10L, 10R are installed near runway 46 in manner whereby two sets of blinking and steady beams are projected in the direction of incoming aircraft 48, and are otherwise substantially identical to each other except that one of the indicators 10L,10R is positioned to project a pair of light beams at slightly higher angles relative to ground level than the other. Accordingly, indicator 10L is installed to project a blinking beam BL and a steady beam SL having an overlap OL elevated at an angle θ 1 with respect to ground level G. Similarly, indicator 10R is installed to project blinking and steady beams BR,SR having an overlap OR elevated at an angle θ 2 with respect to ground level.
Referring additionally now to FIG. 4, shown therein is a view along line D--D of FIG. 3, including superimposition of beams SR,BR,SL,BL. As indicated above, one indicator (10R in the example given in FIG. 3) projects beams at a slightly higher angle than the other, and, according, θ 2 is somewhat larger than θ 1 . In the use of the invention herein as a glide slope indicator system, indicators 10L,10R are installed with θ 2 somewhat larger than angle θ g defining the desired glide slope 49 for aircraft 48, and θ 1 somewhat smaller than θ g . The system depicted in FIGS. 3 and 4 may be set up for any selected glide slope 49 and either indicator 10L,10R may be selected for the higher beam projection. The angular difference θ 2 -θ 1 between the beam projections for indicators 10L,10R may be varied depending on the precision needed for glide slope 49 corresponding to aircraft type, runway conditions, and visibility. For example, if the available runway 46 is short or obstacles exist near glide path 49, beam projections characterized by a small θ 2 -θ 1 difference may be desirable. Notwithstanding, in a system built and operated successfully in demonstration of the invention, selected θ 2 -θ 1 values of from about 1/4° to 1/2° for beam divergence angles b,s of from about 9° to 11°, and glide slope angles θ g of from about 21/2° to 3° were characteristic.
Referring now additionally to FIG. 5, which is a view along line E--E of FIG. 4, the operation of the glide slope indicator system of the present invention may be summarized as follows. A pilot of an incoming aircraft 48 will observe two lights 51,52 between which resides threshold 47 of runway 46. If aircraft 48 is approaching on a course above a preselected glide slope 49 (i.e., above OR) both steady beams SL,SR will be observed from the respective indicators 10L,10R. If aircraft 48 is too low with respect to glide slope 49, (i.e., below OL), both blinking beams BL,BR will be observed. If, however, aircraft 48 is acceptably close to glide slope 49 (i.e., within an envelope of angular size θ 2 -θ 1 between OR and OL), indicator 10L will present steady beam SL and indicator 10R will present blinking beam BR to the pilot. It is noteworthy that in reversing the positions of indicators 10R,10L with respect to runway 46, one blinking and one steady beam will still be observed from an aircraft approaching acceptably close to glide slope 49 between OL and OR.
It is instructive to note that use of a pair of indicators 10L,10R at the end of runway 46 (such as depicted in FIG. 3) does not provide precise runway bearing (azimuthal) cues to incoming aircraft 48. Runway bearing cues, if needed by an incoming aircraft, may be given separately from the glide slope cues provided by the present invention, such as by one or more runway lights deployed along the length of runway 46 or by radio signal. Notwithstanding, in the unit built in demonstration of the invention, accurate cues as to runway bearing were obtainable using the invention within about ±10° azimuth relative to true runway heading. Naked eye visibility of the invention using 12 watt incandencent bulbs without infrared filter was about 6 miles.
The present invention therefore provides a portable glide slope indicator system for aiding aircraft landing at night on an otherwise remote, austere, unit or unmarked field. It is understood that certain modifications to the invention as described may be made, as might occur to one with skill in the field of this invention, within the scope of the appended claims. Therefore, all embodiments contemplated hereunder which achieve the objects of the invention have not been shown in complete detail. Other embodiments may be developed without departing from the spirit of the invention or from the scope of the appended claims. | An improved glide slope indicator system for facilitating aircraft landings under adverse lighting conditions on remote or austere landing sites is provided which comprises a pair of indicators deployable near ground level on each side of a runway, each indicator including a housing having an optical window and a pair of light sources mounted in predetermined spaced relationship to each other and to the optical window and connected to a power source and related circuitry to project a well defined first blinking and second steady light beam of predetermined angular divergence and overlap, one indicator disposed to project beams with an overlap elevated at a first angle relative to horizontal and the other indicator disposed to project beams with an overlap elevated at a second angle relative to horizontal different from the first, with a preselected glide path lying between the two overlaps. An infrared filter may be included in each indicator to project beams observable only with infrared sensitive viewing aids. The system may be battery powered for portability. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of copending U.S. Ser. No. 13/257,255 having an international filing date of 17 Mar. 2010, which is the national phase of PCT application PCT/NL2010/050138 having an international filing date of 17 Mar. 2010, which claims benefit of European application No. 09155380.0 filed 17 Mar. 2009. The contents of the above patent applications are incorporated by reference herein in their entirety.
REFERENCE TO SEQUENCE LISTING SUBMITTED VIA EFS-WEB
[0002] The entire content of the following electronic submission of the sequence listing via the USPTO EFS-WEB server, as authorized and set forth in MPEP §1730 II.B.2(a)(C), is incorporated herein by reference in its entirety for all purposes. The sequence listing is identified on the electronically filed text file as follows:
[0000]
File Name
Date of Creation
Size (bytes)
313632012110Seqlist.txt
Apr. 11, 2014
266,239 bytes
FIELD OF THE INVENTION
[0003] This invention is related to the field of enzymatic digest of carbohydrate polymers, more specifically enzymatic modification, conversion and degradation of lignocellulose and (hemi-)cellulose containing substrates.
BACKGROUND ART
[0004] Carbohydrates constitute the most abundant organic compounds on earth. However, much of this carbohydrate is sequestered in complex polymers including starch (the principle storage carbohydrate in seeds and grain), and a collection of carbohydrates and lignin known as lignocellulose. The main carbohydrate components of lignocellulose are cellulose, hemicellulose, and glucans. These complex polymers are often referred to collectively as lignocellulose. Cellulose is a linear polysaccharide composed of glucose residues linked by beta-1,4 bonds. The linear nature of the cellulose fibers, as well as the stoichiometry of the beta-linked glucose (relative to alpha) generates structures more prone to interstrand hydrogen bonding than the highly branched alpha-linked structures of starch. Thus, cellulose polymers are generally less soluble, and form more tightly bound fibers than the fibers found in starch. Hemicellulose is a complex polymer, and its composition often varies widely from organism to organism, and from one tissue type to another. In general, a main component of hemicellulose is beta-1,4-linked xylose, a five carbon sugar. However, this xylose is often branched as beta-1,3 linkages, and can be substituted with linkages to arabinose, galactose, mannose, glucuronic acid, or by esterification to acetic acid. Hemicellulose can also contain glucan, which is a general term for beta-linked six carbon sugars. The composition, nature of substitution, and degree of branching of hemicellulose is very different in dicot plants as compared to monocot plants. In dicots, hemicellulose is comprised mainly of xyloglucans that are 1,4-beta-linked glucose chains with 1,6-beta-linked xylosyl side chains. In monocots, including most grain crops, the principle components of hemicellulose are heteroxylans. These are primarily comprised of 1,4-beta-linked xylose backbone polymers with 1,3-beta linkages to arabinose, galactose and mannose as well as xylose modified by ester-linked acetic acids. Also present are branched beta glucans comprised of 1,3- and 1,4-beta-linked glucosyl chains. In monocots, cellulose, heteroxylans and beta glucans are present in roughly equal amounts, each comprising about 15-25% of the dry matter of cell walls.
[0005] The sequestration of such large amounts of carbohydrates in plant biomass provides a plentiful source of potential energy in the form of sugars, both five carbon and six carbon sugars that could be utilized for numerous industrial and agricultural processes. However, the enormous energy potential of these carbohydrates is currently under-utilized because the sugars are locked in complex polymers, and hence are not readily accessible for fermentation. Methods that generate sugars from plant biomass would provide plentiful, economically-competitive feedstocks for fermentation into chemicals, plastics, and fuels. Current processes to generate soluble sugars from lignocellulose are complex. A key step in the process is referred to as pretreatment. The aim of pretreatment is to increase the accessibility of cellulose to cellulose-degrading enzymes, such as the cellulase mixture derived from fermentation of the fungus Trichoderma reesei . Current pretreatment processes involve steeping lignocellulosic material such as corn stover in strong acids or bases under high temperatures and pressures. Such chemical pretreatments degrade hemicellulose and/or lignin components of lignocellulose to expose cellulose, but also create unwanted by-products such as acetic acid, furfural, hydroxymethyl furfural and gypsum. These products must be removed in additional processes to allow subsequent degradation of cellulose with enzymes or by a co-fermentation process known as simultaneous saccharification and fermentation (SSF). The conditions currently used for chemical pretreatments require expensive reaction vessels, and are energy intensive. Chemical pretreatment occurring at high temperatures and extreme pH conditions (for example 160° C. and 1.1% sulfuric acid at 12 atm. pressure) are not compatible with known cellulose-degrading enzymes. Further, these reactions produce compounds that must be removed before fermentation can proceed. As a result, chemical pretreatment processes currently occur in separate reaction vessels from cellulose degradation, and must occur prior to cellulose degradation.
[0006] Thus, methods that are more compatible with the cellulose degradation process, do not require high temperatures and pressures, do not generate toxic waste products, and require less energy, are desirable. For these reasons, efficient methods are needed for biomass conversion.
[0007] Filamentous fungi are efficient producers of a large variety of enzymes, and, therefore, they are exploited already for decades for the production of enzymes at industrial scale. Numerous hydrolytic activities have been identified for hydrolysis of starch, (hemi)cellulose and inulin. For many of these enzymes industrial processes have been developed.
[0008] Based on extensive research on these carbohydrolytic enzymes, besides catalytic domains also domains involved in substrate binding have been identified. For fungal enzymes in particular, most of the lignocellulose and (hemi-)cellulose degrading enzymes are characterized by having a cellulose binding domain, denominated as CBM1 (see also www.cazy.org/fam/acc_CBM.html. Interestingly, in particular for CBM1, which is unique to fungi, proteins with completely different catalytic activities have been identified. Besides different types of (hemi)cellulases, xylanases, pectinases, esterases, chitinases and lipases amongst others also CBM-1 proteins with unknown activity have been identified. The largest gene family of this latter class is the GH61 protein/gene family. However, there is still need for further enzymes involved in lignocellulose and (hemi-)cellulose degradation.
SUMMARY OF THE INVENTION
[0009] The inventors have now discovered two novel gene families of lignocellulose active enzymes, sharing a hitherto unknown domain (sometimes in addition to a CBM1 domain). Therefore the invention comprises a lignocellulose and/or (hemi-)cellulose active protein comprising the domain with the amino acid sequence
[0000]
(SEQ ID NOS: 1-2)
[DN]-P-[IVL]-[MAIV]-X-[PAF]-[GNQ]-X 3−4 -[SAP]-X 1−2 -
H-X-H-X 3 -G-X 16−21 -C-[ST]-[ST]-X 5 -D-X-S-[AN]-Y-[YW]-
X-[AP]-X-[LVM]-X 2−9 -G
[0010] or a sequence that has an identity of more than 70%, preferably more than 75%, more preferably more than 80%, more preferably more than 85%, more preferably more than 90%, more preferably more than 95%, more preferably more than 98% with said amino acid sequence. Preferably said protein comprises the sequence DPLVFPGAM QSPHVHQIVG GNMFNVTMDP NRHNIGEEAT CTTCTFSEDF SNYWTAILYF RARNGTLIRV PQRPNIDFDG ARGGGMTVYY TATYQNHKPT AFQPGFRMIV GNPMYRTQAE ASRYRQMTFT CLETLSTRTG ETTEMPKQPC REGIMSNVRF PTCWDGKTLD PPDHSSHVAY PSSGTFESGG PCPASHPVRI PQLFYEVLWD TRRFNDRSLW PEDGSQPFVW SYGDYTGYGT HGDYVFGWKG I, (SEQ ID NO:4) or, alternatively, the sequence GAPSVHAVLR FSCSELVTER LDPLVFPGAM QSPHVHQIVG GNMFNVTMDP NRHNIGEEAT CTTCTFSEDF SNYWTAILYF RARNGTLIRV PQRPNIDFDG ARGGGMTVYY TATYQNHKPT AFQPGFRMIV GNPMYRTQAE ASRYRQMTFT CLETLSTRTG ETTEMPKQPC REGIMSNVRF PTCWDGKTLD PPDHSSHVAY PSSGTFESGG PCPASHPVRI PQLFYEVLWD TRRFNDRSLW PEDGSQPFVW SYGDYTGYGT HGDYVFGWKG DSLQRAMDAN CDFYCPQLKT QSIATGNQCR QNQKVAENID1 GPFDRLPGNV EITGPQPGAS (SEQ ID NO:5) or a sequence that has an identity of more than 70%, preferably more than 75%, more preferably more than 80%, more preferably more than 85%, more preferably more than 90%, more preferably more than 95%, more preferably more than 98% with said amino acid sequences. Said protein is preferably selected from the group consisting of the proteins with the NCBI accession no. XP — 001907658.1 (SEQ ID NO:16), XP — 001904981.1 (SEQ ID NO:17), XP — 001911253.1 (SEQ ID NO:18), XP — 001911467.1 (SEQ ID NO:19), XP — 001908261.1 (SEQ ID NO:20), XP — 001907671.1 (SEQ ID NO:21), XP — 001906312.1 (SEQ ID NO:22), XP — 001912166.1 (SEQ ID NO:23), XP — 001904033.1 (SEQ ID NO:24), XP — 001905336.1 (SEQ ID NO:25), XP — 001904002.1 (SEQ ID NO:26), XP — 001905175.1 (SEQ ID NO:27), XP — 001911617.1 (SEQ ID NO:28), XP — 001907672.1 (SEQ ID NO:29), XP — 001903756.1 (SEQ ID NO:30), XP — 001903833.1 (SEQ ID NO:31), XP — 001904389.1 (SEQ ID NO:32), XP — 001904303.1 (SEQ ID NO:33), XP — 001903094.1 (SEQ ID NO:34), XP — 001904583.1 (SEQ ID NO:35), XP — 001904957.1 (SEQ ID NO:36), XP — 001906851.1 (SEQ ID NO:37), XP — 001903754.1 (SEQ ID NO:38), XP — 001911708.1 (SEQ ID NO:39), XP — 001907931.1 (SEQ ID NO:40), and XP — 001903118.1 (SEQ ID NO:41) from Podospora anserina , BAE61525.1 (SEQ ID NO:42), BAE54784.1 (SEQ ID NO:43) and BAE66576.1 (SEQ ID NO:44) from Aspergillus oryzae , CAK38435.1 (SEQ ID NO:45) and CAK40357.1 (SEQ ID NO:46) from Aspergillus niger and three proteins from Trichoderma reesei (proteins 108655 (SEQ ID NO:47), 37665 (SEQ ID NO:48) and 102735 (SEQ ID NO:49) from the T. reesei protein database at JTI, genome.jgi-psf.org/Trire2/Trire2.home.html). Also preferred is a protein according to the invention that additionally comprises a CBM1 domain, preferably wherein said CBM1 domain comprises the consensus sequence C-G (2) -X (4-7) -G-X (3) -C-X (4,5) -C-X (3-5) -[NHGS]-X-[FYWMI]-X (2) -Q-C (SEQ ID NO:9), more preferably wherein said protein is the protein from Podospora anserina with the NCBI accession no. CAP68330.1 (SEQ ID NO:81).
[0011] In another embodiment, the invention comprises a lignocellulose and/or (hemi-)cellulose active protein comprising the domain with the amino acid sequence [GA]-[ST]-[IV]-[ILV]-W-[DS]-G-[RIFS]-F-[ND]-[DS]-X 2 -[TS]-X 2 -D-[LIF]-[ND]-K-W-S-W-[GSA]-N-Q-[IV]-[GP]-[PS]-[YW]-X 0-4 -Q-[YW]-Y-I-H-G-S-X 2 -[VT]-X 2 -Y-[ILV]-X[ILV]-S-X 2 -[FY]-K-N-P-X 5-7 -Q-G-X-[KR]-I-T-[LI]-D-X-[ST]-[AS]-X-W-N-G-Q-[NT]-M-X-R-[IST]-E-L-I-P-Q-T-X 6-13 -G-X-[KLV]-[FY]-Y-H-F-S-[ILV]-X 5 -N-A-P-X 4 -E-H-Q-[ILV]-[AC]-F-F-E-X 0-13 -S-H-F-T-E-[LM]-K-[YST]-G-W-X 0-2 -G-X 6-33 -[LF]-X 1-24 -I-D-F-[ASD]-X 3-8 -V-[FL]-[FWY]-X-S-[ENT]-G-X 2-5 -[AP]-L-X 2-4 -[AV]-[AV]-X-[PAN]-X 3-5 -[ANS]-[AT]-[AFS]-[ST]-[DN]-[GS]-[AQ]-D-[FW]-H-{FILV}-G-[EIQV]-L-[ERK]-[ILV]-P-X 8-18 -E-D-[FWY]-[FY]-[FW]-S-G-[IV]-[FY]-[IV]-E (SEQ ID NOS:6-7) or a sequence that has an identity of more than 70%, preferably more than 75%, more preferably more than 80%, more preferably more than 85%, more preferably more than 90%, more preferably more than 95%, more preferably more than 98% with said amino acid sequence. Preferably such a protein comprises the sequence GT ILWDGRFNDM TSSADLNKWS WGNQVGPYQY YIHGSSPVSA YVNLSPDYKN PADTGSRQGA KITLDNTAYW NGQNMRRTEL IPQTTAAINQ GKVYYHFSLM RKDINAPATT REHQIAFFES HFTELKSGWL SGAPGISDTL LRWCIDFAAG TVGFWHSTGS DPLTRKVAPV KTSTSSNGAD WHVGVLELPR SGYPDSNEDF YWSGVYIESG SLTTSVAGPG QPIPGDGG (SEQ ID NO:3) or a sequence that has an identity of more than 70%, preferably more than 75%, more preferably more than 80%, more preferably more than 85%, more preferably more than 90%, more preferably more than 95%, more preferably more than 98% with said amino acid sequence. Preferably said protein is selected from the group consisting of the proteins from Podospora anserina with the NCBI accession numbers XP — 001903534.1 (CAP61309.1) (SEQ ID NO:50) and XP — 001907960.1 (CAP68633.1) (SEQ ID NO:51), from Aspergillus flavus (EED52126.1 (SEQ ID NO:52) and EED54304.1 (SEQ ID NO:53)), from Aspergillus fumigatus (XP — 751054.2 (SEQ ID NO:54), XP — 755877.1 (SEQ ID NO:55) and EDP49742.1 (SEQ ID NO:56)), Aspergillus clavatus (XP — 001275827.1) (SEQ ID NO:57), Aspergillus oryzae (XP — 001825707.1) (SEQ ID NO:58), Aspergillus terreus (XP — 001211584.1) (SEQ ID NO:59), Aspergillus nidulans (XP — 680867.1) (SEQ ID NO:60), Aspergillus niger (XP — 001392581.1) (SEQ ID NO:61), Magnaporthe griseae (XP — 362641.1 (SEQ ID NO:62) and XP — 001408874.1 (SEQ ID NO:63)), Phaeosphaeria nodorum (XP — 001793212.1 (SEQ ID NO:64) and XP — 001799980.1 (SEQ ID NO:65)), Neurospra crassa (XP — 958348.1 (SEQ ID NO:66) and XP — 956768.1 (SEQ ID NO:67)), Pyrenophora tritici - repentis (XP — 001932168.1 (SEQ ID NO:68) and XP — 001931381.1 (SEQ ID NO:69)), Neosartorya fischeri (XP — 001258287.1 (SEQ ID NO:70) and XP — 001261005.1 (SEQ ID NO:71)), Chaetomiun globosum (XP — 001228503) (SEQ ID NO:72), Botryotinia fuckeliana (XP — 001546653.1) (SEQ ID NO:73), Sclerotinia sclerotiorum (XP — 001593519.1) (SEQ ID NO:74), Moniliophthora perniciosa (EEB91913.1) (SEQ ID NO:75) and Coprionopsis cinerea (XP — 001835742) (SEQ ID NO:76).
[0012] In another embodiment, said protein additionally comprises a CBM1 domain, and is preferably selected from the group consisting of the proteins with NCBI accession no. CAP61309.1 (SEQ ID NO:77), BAE64574.1 (SEQ ID NO:78) and CAK45436.1 (SEQ ID NO:79).
[0013] In a preferred embodiment the protein from the invention is from fungal origin, preferably wherein the fungus is chosen from the group consisting of Aspergillus, Neurospora, Sclerotina, Gibberella, Coniothyrium, Psiticum, Magnaporthe, Podospora, Chaetomium, Phaeosphaeria, Botryotinia, Neosartorya, Pyrenophora, Panicum, Aureococcus, Trichoderma Penicillium and Chrysosporium.
[0014] Also part of the invention is a nucleic acid encoding a protein according to the invention, a vector comprising said nucleic acid and a host cell capable of expressing a protein according to the invention by harbouring said nucleic acid or vector.
[0015] Further, also comprised in the invention is the use of a protein according to the invention in the modification of a raw carbohydrate, preferably lignocellulose and/or (hemi-)cellulose, most preferably non-soluble cellulose, preferably wherein the protein has or enhances cellulase activity.
LEGENDS TO THE FIGURES
[0016] FIG. 1 . SDS PAGE of proteins produced by A. niger transformants transgenic for CAP68330 and CAP61309. M indicates marker lane.
DETAILED DESCRIPTION
[0017] The term “sequence identity,” as used herein, is generally expressed as a percentage and refers to the percent of amino acid residues or nucleotides, as appropriate, that are identical as between two sequences when optimally aligned. For the purposes of this invention, sequence identity means the sequence identity determined using the well-known Basic Local Alignment Search Tool (BLAST), which is publicly available through the National Cancer Institute/National Institutes of Health (Bethesda, Md.) and has been described in printed publications (see, e.g., Altschul et al., J. MoI. Biol, 215(3), 403-10 (1990)). Preferred parameters for amino acid sequences comparison using BLASTP are gap open 11.0, gap extend 1, Blosum 62 matrix. Protein analysis software matches similar sequences using measures of homology assigned to various substitutions, deletions and other modifications. Conservative substitutions typically include substitutions within the following groups: glycine, alanine; valine, isoleucine, leucine; aspartic acid, glutamic acid; asparagine, glutamine; serine, threonine; lysine, arginine; and phenylalanine, tyrosine.
[0018] The term “signal peptide” or “signal sequence” as used herein, refers to an amino acid sequence, typically located at the amino terminus of an immature protein or polypeptide (e.g., prior to secretion from a cell and associated processing and cleavage), which directs the secretion of the protein or polypeptide from the cell in which it is produced. The signal peptide typically is removed from an immature protein or polypeptide prior to or during secretion and, thus, is not present in the mature, secreted polypeptide.
[0019] As used herein, the term “recombinant nucleic acid molecule” refers to a recombinant DNA molecule or a recombinant RNA molecule. A recombinant nucleic acid molecule is any synthetic nucleic acid construct or nucleic acid molecule containing joined nucleic acid molecules from different original sources or and not naturally occurring or attached together and prepared by using recombinant DNA techniques.
[0020] The term “recombinant host cell” as used herein, refers to a host cell strain containing nucleic acid not naturally occurring in that strain and which has been introduced into that strain using recombinant DNA techniques.
[0021] The term “nucleic acid” as used herein, includes reference to a deoxyribonucleotide or ribonucleotide polymer, i.e. a polynucleotide, in either single- or double-stranded form, and unless otherwise limited, encompasses known analogues having the essential nature of natural nucleotides in that they hybridize to single-stranded nucleic acids in a manner similar to naturally occurring nucleotides (e.g., peptide nucleic acids). A polynucleotide can be full-length or a subsequence of a native or heterologous structural or regulatory gene. Unless otherwise indicated, the term includes reference to the specified sequence as well as the complementary sequence thereof. Thus, DNAs or RNAs with backbones modified for stability or for other reasons are “polynucleotides” (a polymeric form of nucleotides, either ribonucleotides or deoxyribonucleotides, double- or single-stranded of any length) as that term is intended herein. Moreover, DNAs or RNAs comprising unusual bases, such as inosine, or modified bases, such as tritylated bases, to name just two examples, are polynucleotides as the term is used herein. It will be appreciated that a great variety of modifications have been made to DNA and RNA that serve many useful purposes known to those of skill in the art. The term polynucleotide as it is employed herein embraces such chemically, enzymatically or metabolically modified forms of polynucleotides, as well as the chemical forms of DNA and RNA characteristic of viruses and cells, including among other things, simple and complex cells.
[0022] Every nucleic acid sequence herein that encodes a polypeptide also, by reference to the genetic code, describes every possible silent variation of the nucleic acid. The term “conservatively modified variants” applies to both amino acid and nucleic acid sequences. With respect to particular nucleic acid sequences, conservatively modified variants refer to those nucleic acids which encode identical or conservatively modified variants of the amino acid sequences due to the degeneracy of the genetic code.
[0023] The term “degeneracy of the genetic code” refers to the fact that a large number of functionally identical nucleic acids encode any given protein. For instance, the codons GCA, GCC, GCG and GCU all encode the amino acid alanine. Thus, at every position where an alanine is specified by a codon, the codon can be altered to any of the corresponding codons described without altering the encoded polypeptide. Such nucleic acid variations are “silent variations” and represent one species of conservatively modified variation.
[0024] The term “gene”, as used herein, refers to a nucleic acid sequence containing a template for a nucleic acid polymerase, in eukaryotes, RNA polymerase II. Genes are transcribed into mRNAs that are then translated into protein.
[0025] “Expression” refers to the transcription of a gene into structural RNA (rRNA, tRNA) or messenger RNA (mRNA) with subsequent translation into a protein.
[0026] The term “complementary”, as used herein, refers to a sequence of nucleotides which forms a hydrogen-bonded duplex with another sequence of nucleotides according to Watson-Crick base-paring rules. For example, the complementary base sequence for 5′-AAGGCT-3′ is 3′-TTCCGA-5′. As used herein, “substantially complementary” means that two nucleic acid sequences have at least about 40, preferably about 50% more preferably at least 55%, more preferably about 60%, more preferably about 70%, more preferably about 80%, even more preferably 90%, and most preferably about 98%, sequence complementarity to each other.
[0027] The term “hybridise” refers to the process by which single strands of nucleic acid sequences form double-helical segments through hydrogen bonding between complementary nucleotides.
[0028] As used herein, the term “expression control sequence” refers to a nucleic acid sequence that regulates the transcription and translation of a gene to which it is operatively linked. An expression control sequence is “operatively linked” to a gene when the expression control sequence controls and regulates the transcription and, where appropriate, translation of the gene. The term “operatively linked” includes the provision of an appropriate start codon (e.g. ATG), in front of a polypeptide-encoding gene and maintaining the correct reading frame of that gene to permit proper translation of the mRNA.
[0029] As used herein, the term “operably linked” refers to a juxtaposition wherein the components so described are in a relationship permitting them to function in their intended manner. A control sequence “operably linked” to another control sequence and/or to a coding sequence is ligated in such a way that transcription and/or expression of the coding sequence is achieved under conditions compatible with the control sequence. Generally, operably linked means that the nucleic acid sequences being linked are contiguous and, where necessary to join two protein coding regions, contiguous and in the same reading frame.
[0030] The term “vector” as used herein, includes reference to an autosomal expression vector and to an integration vector used for integration into the chromosome.
[0031] The term “expression vector” refers to a DNA molecule, linear or circular, that comprises a segment encoding a polypeptide of interest under the control of (i.e., operably linked to) additional nucleic acid segments that provide for its transcription. Such additional segments may include promoter and terminator sequences, and may optionally include one or more origins of replication, one or more selectable markers, an enhancer, a polyadenylation signal, and the like. Expression vectors are generally derived from plasmid or viral DNA, or may contain elements of both. In particular an expression vector comprises a nucleotide sequence that comprises in the 5′ to 3′ direction and operably linked: (a) a fungal-recognized transcription and translation initiation region, (b) a coding sequence for a polypeptide of interest, and (c) a fungal-recognized transcription and translation termination region. “Plasmid” refers to autonomously replicating extrachromosomal DNA which is not integrated into a microorganism's genome and is usually circular in nature.
[0032] An “integration vector” refers to a DNA molecule, linear or circular, that can be incorporated in a microorganism's genome and provides for stable inheritance of a gene encoding a polypeptide of interest. The integration vector generally comprises one or more segments comprising a gene sequence encoding a polypeptide of interest under the control of (i.e., operably linked to) additional nucleic acid segments that provide for its transcription. Such additional segments may include promoter and terminator sequences, and one or more segments that drive the incorporation of the gene of interest into the genome of the target cell, usually by the process of homologous recombination. Typically, the integration vector will be one which can be transferred into the host cell, but which has a replicon which is nonfunctional in that organism. Integration of the segment comprising the gene of interest may be selected if an appropriate marker is included within that segment.
[0033] “Transformation” and “transforming”, as used herein, refers to the insertion of an exogenous polynucleotide into a host cell, irrespective of the method used for the insertion, for example, direct uptake, transduction, f-mating or electroporation. The exogenous polynucleotide may be maintained as a non-integrated vector, for example, a plasmid, or alternatively, may be integrated into the host cell genome.
[0034] By “host cell” is meant a cell which contains a vector or recombinant nucleic acid molecule and supports the replication and/or expression of the vector or recombinant nucleic acid molecule. Host cells may be prokaryotic cells such as E. coli , or eukaryotic cells such as yeast, fungus, plant, insect, amphibian, or mammalian cells. Preferably, host cells are fungal cells.
[0035] The term “fungus” or “fungi” includes a wide variety of nucleated, spore-bearing organisms which are devoid of chlorophyll. Examples of fungi include yeasts, mildews, molds, rusts and mushrooms. Preferred fungi in aspects of the present invention are organisms of the genera Aspergillus, Neurospora, Sclerotina, Gibberella, Coniothyrium, Psiticum, Magnaporthe, Podospora, Chaetomium, Phaeosphaeria, Botryotinia, Neosartorya, Pyrenophora, Panicum, Aureococcus Penicillium and Chrysospsorium.
[0036] The terms “isolated” or “purified” as used herein refer to a nucleic acid or protein or peptide that is removed from at least one component with which it is naturally associated. In the present invention, an isolated nucleic acid can include a vector comprising the nucleic acid. Purified as used herein to describe a polypeptide produced by cultivation of a recombinant host cell refers to removing that polypeptide from at least one component with which it is naturally associated in the host cell or culture medium.
[0037] The CBM1 domain that is present in many of the proteins that are held to have activity on cellulose, chitin, sepharose, xylan has a consensus amino acid sequence that can be denoted as:
[0000] (SEQ ID NO: 9) C-G (2) -X (4−7) -G-X (3) -C-X (4−5) -C-X (3−5) -[NHGS]-X- [FYWMI]-x (2) -Q-C
in which the amino acids between square brackets are alternatives on that position, and X n denotes a series of n freely chosen amino acids. Alternatively, the CBM1 domain is a sequence that has a high identity with the above consensus sequence. However, no or only very limited catalytic activity has been shown to reside in or be linked to said CBM1 domain.
[0038] Now, the inventors have discovered two novel classes of starch active proteins wherein the first class shares a common domain of unknown function (D-U-F), also called the DUF1996 domain, partly represented by the consensus sequence:
[0000]
(SEQ ID NOS: 1-2)
[DN]-P-[IVL]-[MAIV]-x-[PAF]-[GNQ]-X 3−4 -[SAP]-X 1−2 -
H-X-H-X 3 -G-X 16−21 -C-[ST]-[ST]-X 5 -D-X-S-[AN]-Y-[YW]-
X-[AP]-X-[LVM]-X 2−9 -G
[0039] in which the amino acids between square brackets are alternatives at the same position and X n denotes a series of n freely chosen amino acids, or an amino acid sequence that has a high degree of identity with said consensus sequence.
[0040] An example of such a domain is the sequence:
[0000] (SEQ ID NO: 4) DPLVFPGAM QSPHVHQIVG GNMFNVTMDP NRHNIGEEAT CTTCTFSEDF SNYWTAILYF RARNGTLIRV PQRPNIDFDG ARGGGMTVYY TATYQNHKPT AFQPGFRMIV GNPMYRTQAE ASRYRQMTFT CLETLSTRTG ETTEMPKQPC REGIMSNVRF PTCWDGKTLD PPDHSSHVAY PSSGTFESGG PCPASHPVRI PQLFYEVLWD TRRFNDRSLW PEDGSQPFVW SYGDYTGYGT HGDYVFGWKG I,
and also the sequence:
[0000] (SEQ ID NO: 5) GAPSVHAVLR FSCSELVTER LDPLVFPGAM QSPHVHQIVG GNMFNVTMDP NRHNIGEEAT CTTCTFSEDF SNYWTAILYF RARNGTLIRV PQRPNIDFDG ARGGGMTVYY TATYQNHKPT AFQPGFRMIV GNPMYRTQAE ASRYRQMTFT CLETLSTRTG ETTEMPKQPC REGIMSNVRF PTCWDGKTLD PPDHSSHVAY PSSGTFESGG PCPASHPVRI PQLFYEVLWD TRRFNDRSLW PEDGSQPFVW SYGDYTGYGT HGDYVFGWKG DSLQRAMDAN CDFYCPQLKT QSIATGNQCR QNQKVAENID1 GPFDRLPGNV EITGPQPGAS
or an amino acid sequence that has a high degree of identity with said sequences. A high degree of identity is herein defined as an identity of more than 70%, preferably more than 75%, more preferably more than 80%, more preferably more than 85%, more preferably more than 90%, more preferably more than 95%, more preferably more than 98%. Species of proteins with this new domain are 26 proteins from Podospora anserina (accession numbers XP — 001907658.1 (SEQ ID NO:16), XP — 001904981.1 (SEQ ID NO:17), XP — 001911253.1, (SEQ ID NO:18) XP — 001911467.1 (SEQ ID NO:19), XP — 001908261.1 (SEQ ID NO:20), XP — 001907671.1 (SEQ ID NO:21), XP — 001906312.1 (SEQ ID NO:22), XP — 001912166.1 (SEQ ID NO:23), XP — 001904033.1 (SEQ ID NO:24), XP — 001905336.1 (SEQ ID NO:25), XP — 001904002.1 (SEQ ID NO:26), XP — 001905175.1 (SEQ ID NO:27), XP — 001911617.1 (SEQ ID NO:28), XP — 001907672.1 (SEQ ID NO:29), XP — 001903756.1 (SEQ ID NO:30), XP — 001903833.1 (SEQ ID NO:31), XP — 001904389.1 (SEQ ID NO:32), XP — 001904303.1 (SEQ ID NO:33), XP — 001903094.1 (SEQ ID NO:34), XP — 001904583.1 (SEQ ID NO:35), XP — 001904957.1 (SEQ ID NO:36), XP — 001906851.1 (SEQ ID NO:37), XP — 001903754.1 (SEQ ID NO:38), XP — 001911708.1 (SEQ ID NO:39), XP — 001907931.1 (SEQ ID NO:40), XP — 001903118.1 (SEQ ID NO:41), BAE61525.1 (SEQ ID NO:42), BAE54784.1 (SEQ ID NO:43) and BAE66576.1 (SEQ ID NO:44) from Aspergillus oryzae , CAK38435.1 (SEQ ID NO:45) and CAK40357.1 (SEQ ID NO:46) from Aspergillus niger and three proteins from Trichoderma reesei (proteins 108655 (SEQ ID NO:47), 37665 (SEQ ID NO:48) and 102735 (SEQ ID NO:49) from the T. reesei protein database at JTI, genome.jgi-psf.org/Trire2/Trire2.home.html, see Martinez, D. et al., 2008, Nature Biotechnology 26, 553-560).
[0041] This new class of proteins has been discovered in the search for proteins with CBM1 domains. It appeared that several of the proteins, especially those from fungal origin contained the above conserved DUF1996 domain next to the CBM1 domain. Further search for more proteins that also comprised the conserved DUF1996 domain has led to the proteins of the present invention. It is submitted that for all currently known proteins with said domain that are listed above and/or in the experimental part no function was hitherto known from any of these proteins. A species of a protein with both CBM1 and DUF1996 domains is CAP68330.1 from Podospora anserine (SEQ ID NO:81).
[0042] A further new class of proteins concerns proteins that have the domain with the consensus sequence: [GA]-[ST]-[IV]-[ILV]-W-[DS]-G-[RIFS]-F-[ND]-[DS]-X 2 -[TS]-X 2 -D-[LIF]-[ND]-K-W-S-W-[GSA]-N-Q-[IV]-[GP]-[PS]-[YW]-X 0-4 -Q-[YW]-Y-I-H-G-S-X 2 -[VT]-X 2 -Y-[ILV]-X[ILV]-S-X 2 -[FY]-K-N-P-X 5-7 -Q-G-X-[KR]-I-T-[LI]-D-X-[ST]-[AS]-X-W-N-G-Q-[NT]-M-X-R-[IST]-E-L-I-P-Q-T-X 6-13 -G-X-[KLV]-[FY]-Y-H-F-S-[ILV]-X 5 -N-A-P-X 4 -E-H-Q-[ILV]-[AC]-F-F-E-X 0-13 -S-H-F-T-E-[LM]-K-[YST]-G-W-X 0-2 -G-X 6-33 -[LF]-X 1-24 -I-D-F-[ASD]-X 3-8 -V-[FL]-[FWY]-X-S-[ENT]-G-X 2-5 -[AP]-L-X 2-4 -[AV]-[AV]-X-[PAN]-X 3-5 -[ANS]-[AT]-[AFS]-[ST]-[DN]-[GS]-[AQ]-D-[FW]-H-{FILV}-G-[EIQV]-L-[ERK]-[ILV]-P-X 8-18 -E-D-[FWY]-[FY]-[FW]-S-G-[IV]-[FY]-[IV]-E (SEQ ID NOS:6-7) or an amino acid sequence that has a high degree of identity with this sequence. Particularly, the domain comprises the sequence GT ILWDGRFNDM TSSADLNKWS WGNQVGPYQY YIHGSSPVSA YVNLSPDYKN PADTGSRQGA KITLDNTAYW NGQNMRRTEL IPQTTAAINQ GKVYYHFSLM RKDINAPATT REHQIAFFES HFTELKSGWL SGAPGISDTL LRWCIDFAAG TVGFWHSTGS DPLTRKVAPV KTSTSSNGAD WHVGVLELPR SGYPDSNEDF YWSGVYIESG SLTTSVAGPG QPIPGDGG (SEQ ID NO:3) or an amino acid sequence that has a high degree of identity therewith. A high degree of identity is herein defined as an identity of more than 70%, preferably more than 75%, more preferably more than 80%, more preferably more than 85%, more preferably more than 90%, more preferably more than 95%, more preferably more than 98%. Species of a protein with this new domain are two proteins from Podospora anserina with accession numbers XP — 001903534.1 (CAP61309.1) and XP — 001907960.1 (CAP68633.1), wherein CAP61309 comprises the sequence
[0000] (SEQ ID NO: 10) 19 GTILWDGRFNDMTSSADLNKWSWGNQVGPYQYYIHGSSP VSAYVNLSPDYKNPADTGSRQ 79 GAKITLDNTAYWNGQNMRRTELIPQTTAAINQGKVYYHF SLMRKDINAPATTREHQIAFF 139 ESHFTELKSGWLSGAPGISDTLLRWCIDFAAGTVGFWHS TGSDPLTRKVAPVKTSTSSNG 199 ADWHVGVLELPRSGYPDSNEDFYWSGVYIESGSLTTSVA 248 GPGQPIPGDGG
and CAP68633 comprises the sequence
[0000]
(SEQ ID NO: 11)
19
GAVLWDGRFNDFTSSADLNKWSWANQVGPYPFTNKEYY
IHGSGTVNRYINLSPDYKNPND
79
TVSKQGARFTLDSTAYWNGQTMRRIELIPQTKAAINRG
KVFYHFSISRRDTNAPSVNKEH
139
QICFFESHFTELKYGWISGEQGAANPALQWMTNQRTQW
KLSEWKANVWHNFAYEIDFSGN
199
RVGLWYSEGGADLKQVVAPVGGVSTSSNGQDWHLGVLE
LPRSGYPNTNEDYYFSGVFIED
259
GAITTKIGGPGE
270
[0043] Other examples of this new class of proteins are hitherto hypothetical proteins with unknown function from Aspergillus flavus (EED52126.1 (SEQ ID NO:52) and EED54304.1 (SEQ ID NO:53)), from Aspergillus fumigatus (XP — 751054.2 (SEQ ID NO:54), XP — 755877.1 (SEQ ID NO:55) and EDP49742.1 (SEQ ID NO:56)), Aspergillus clavatus (XP — 001275827.1) (SEQ ID NO:57), Aspergillus oryzae (XP — 001825707.1) (SEQ ID NO:58), Aspergillus terreus (XP — 001211584.1) (SEQ ID NO:59), Aspergillus nidulans (XP — 680867.1) (SEQ ID NO:60), Aspergillus niger (XP — 001392581.1) (SEQ ID NO:61), Magnaporthe griseae (XP — 362641.1 (SEQ ID NO:62) and XP — 001408874.1 (SEQ ID NO:63)), Phaeosphaeria nodorum (XP — 001793212.1 (SEQ ID NO:64) and XP — 001799980.1 (SEQ ID NO:65)), Neurospra crassa (XP — 958348.1 (SEQ ID NO:66) and XP — 956768.1 (SEQ ID NO:67)), Pyrenophora tritici - repentis (XP — 001932168.1 (SEQ ID NO:68) and XP — 001931381.1 (SEQ ID NO:69)), Neosartorya fischeri (XP — 001258287.1 (SEQ ID NO:70) and XP — 001261005.1 (SEQ ID NO:71)), Chaetomiun globosum (XP — 001228503) (SEQ ID NO:72), Botryotinia fuckeliana (XP — 001546653.1) (SEQ ID NO:73), Sclerotinia sclerotiorum (XP — 001593519.1) (SEQ ID NO:74), Moniliophthora perniciosa (EEB91913.1) (SEQ ID NO:75) and Coprionopsis cinerea (XP — 001835742) (SEQ ID NO:76).
[0044] This second new class of proteins has also been discovered in the search of proteins with CBM1 domains. It appeared that several of the proteins, especially those from fungal origin contained the above conserved new domain next to the CBM1 domain. Further search for more proteins that also comprised the conserved new domain has led to the proteins of the present invention. It is submitted that all currently known proteins with said domain or a domain which is highly identical thereto are listed in the experimental part and that no function was hitherto known from any of these proteins. Species of the proteins with both domains are CAP61309.1 (SEQ ID NO:77) from Podospora anserina , BAE64574.1 (SEQ ID NO:78) from Aspergillus oryzae , CAK45436.1 (SEQ ID NO:79) from Aspergillus niger and AN7598.2 from Aspergillus nidulans (SEQ ID NO:80).
[0045] The proteins of the invention are generally derived from fungi.
[0046] Also part of the invention is a nucleotide sequence encoding one or more of the lignocellulose or (hemi-)cellulose active proteins described above. Such a nucleotide sequence can be any nucleotide sequence that encodes said protein(s), but preferably it is the natural coding sequence found in the organisms from which the lignocellulose or (hemi-)cellulose active proteins are derived. However, if these nucleotide sequences are meant for expression in a different host organism, the nucleotide sequence(s) may be adapted to optimize expression is said host organism (codon optimization). For expression purposes, the nucleotide sequence is included in an expression vector that also provides for regulatory sequences, operably linked with the coding nucleotide sequence.
[0047] The proteins of the invention can be used in isolated form for addition to a raw carbohydrate (lignocellulose or (hemi-)cellulose) substrate, alone or together with other lignocellulose or (hemi-)cellulose degrading enzymes, such as (hemi)cellulase, xylanase and/or pectinase. The proteins of the invention may yield a lignocellulose or (hemi-)cellulose hydrolytic activity per se, or they increase the accessibility of the lignocellulose or (hemi-)cellulose by other lignocellulose or (hemi-)cellulose degrading enzymes.
[0048] In another embodiment, the proteins of the invention can be (over)expressed in a host cell. Overexpression of the proteins of the present invention can be effected in several ways. It can be caused by transforming a host cell with a gene coding for a protein of the invention. Alternatively, another method for effecting overexpression is to provide a stronger promoter in front of and regulating the expression of said gene. This can be achieved by use of a strong heterologous promoter or by providing mutations in the endogenous promoter. An increased expression of the protein can also be caused by removing possible inhibiting regulatory proteins, e.g. that inhibit the expression of such proteins. The person skilled in the art will know other ways of increasing the activity of the above mentioned starch active proteins.
[0049] In another aspect of the invention, host cells overexpressing at least one of the above mentioned nucleotide sequences, encoding at least one lignocellulose or (hemi-)cellulose active protein of the invention, are produced and used, for production of said protein(s).
[0050] Host cells used in the invention are preferably cells of filamentous fungi, yeasts and/or bacteria, such as, but not limited to, Aspergillus sp., such as the fungi A. terreus, A. itaconicus and A. niger, Aspergillus nidulans, Aspergillus oryzae or Aspergillus fuminagates, Trichoderma, Penicillium Chrysosporium, Ustilago zeae, Ustilago maydis, Ustilago sp., Candida sp., Yarrowia lipolytica, Rhodotorula sp. and Pseudozyma antarctica , the bacterium E. coli and the yeast Saccharomyces cerevisiae . Especially preferred are host cells that also produce one or more lignocellulose degrading enzymes, such as (hemi)cellulase, xylanase or pectinase.
[0051] Recombinant host cells described above can be obtained using methods known in the art for providing cells with recombinant nucleic acids. These include transformation, transconjugation, transfection or electroporation of a host cell with a suitable plasmid (also referred to as vector) comprising the nucleic acid construct of interest operationally coupled to a promoter sequence to drive expression. Host cells of the invention are preferably transformed with a nucleic acid construct as further defined below and may comprise a single but preferably comprises multiple copies of the nucleic acid construct. The nucleic acid construct may be maintained episomally and thus comprise a sequence for autonomous replication, such as an ARS sequence. Suitable episomal nucleic acid constructs may e.g. be based on the yeast 2μ or pKD1 (Fleer et al., 1991, Biotechnology 9: 968-975) plasmids. Preferably, however, the nucleic acid construct is integrated in one or more copies into the genome of the host cell. Integration into the host cell's genome may occur at random by illegitimate recombination but preferably the nucleic acid construct is integrated into the host cell's genome by homologous recombination as is well known in the art of fungal molecular genetics (see e.g. WO 90/14423, EP-A-0 481 008, EP-A-0 635 574 and U.S. Pat. No. 6,265,186). Most preferably for homologous recombination the ku70Δ/ku80Δ, technique is used as described for instance in WO 02/052026.
[0052] Transformation of host cells with the nucleic acid constructs of the invention and additional genetic modification of the fungal host cells of the invention as described above may be carried out by methods well known in the art. Such methods are e.g. known from standard handbooks, such as Sambrook and Russel (2001) “Molecular Cloning: A Laboratory Manual (3rd edition), Cold Spring Harbor Laboratory, Cold Spring Harbor Laboratory Press, or F. Ausubel et al, eds., “Current protocols in molecular biology”, Green Publishing and Wiley Interscience, New York (1987). Methods for transformation and genetic modification of fungal host cells are known from e.g. EP-A-0 635 574, WO 98/46772, WO 99/60102 and WO 00/37671.
[0053] In another aspect the invention relates to a vector comprising a nucleotide sequence encoding a starch active protein as defined above and usable for transformation of a host cell as defined above. In the nucleic acid construct, the coding nucleotide sequences preferably is/are operably linked to a promoter for control and initiation of transcription of the nucleotide sequence in a host cell as defined below. The promoter preferably is capable of causing sufficient expression of the starch active protein described above, in the host cell. Promoters useful in the nucleic acid constructs of the invention include the promoter that in nature provides for expression of the coding genes. Further, both constitutive and inducible natural promoters as well as engineered promoters can be used. Promoters suitable to drive expression of the genes in the hosts of the invention include e.g. promoters from glycolytic genes (e.g. from a glyceraldehyde-3-phosphate dehydrogenase gene), ribosomal protein encoding gene promoters, alcohol dehydrogenase promoters (ADH1, ADH4, and the like), promoters from genes encoding amylo- or cellulolytic enzymes (glucoamylase, TAKA-amylase and cellobiohydrolase). Other promoters, both constitutive and inducible and enhancers or upstream activating sequences will be known to those of skill in the art. The promoters used in the nucleic acid constructs of the present invention may be modified, if desired, to affect their control characteristics. Preferably, the promoter used in the nucleic acid construct for expression of the genes is homologous to the host cell in which genes are expressed.
[0054] In the nucleic acid construct, the 3′-end of the coding nucleotide acid sequence(s) preferably is/are operably linked to a transcription terminator sequence. Preferably the terminator sequence is operable in a host cell of choice. In any case the choice of the terminator is not critical; it may e.g. be from any fungal gene, although terminators may sometimes work if from a non-fungal, eukaryotic, gene. The transcription termination sequence further preferably comprises a polyadenylation signal.
[0055] Optionally, a selectable marker may be present in the nucleic acid construct. As used herein, the term “marker” refers to a gene encoding a trait or a phenotype which permits the selection of, or the screening for, a host cell containing the marker. A variety of selectable marker genes are available for use in the transformation of fungi. Suitable markers include auxotrophic marker genes involved in amino acid or nucleotide metabolism, such as e.g. genes encoding ornithine-transcarbamylases (argB), orotidine-5′-decarboxylases (pyrG, URA3) or glutamine-amido-transferase indoleglycerol-phosphate-synthase phosphoribosyl-anthranilate isomerases (trpC), or involved in carbon or nitrogen metabolism, such e.g. niaD or facA, and antibiotic resistance markers such as genes providing resistance against phleomycin, bleomycin or neomycin (G418). Preferably, bidirectional selection markers are used for which both a positive and a negative genetic selection is possible. Examples of such bidirectional markers are the pyrG (URA3), facA and amdS genes. Due to their bidirectionality these markers can be deleted from transformed filamentous fungus while leaving the introduced recombinant DNA molecule in place, in order to obtain fungi that do not contain selectable markers. This essence of this MARKER GENE FREE™ transformation technology is disclosed in EP-A-0 635 574, which is herein incorporated by reference. Of these selectable markers the use of dominant and bidirectional selectable markers such as acetamidase genes like the amdS genes of A. nidulans, A. niger and P. chrysogenum is most preferred. In addition to their bidirectionality these markers provide the advantage that they are dominant selectable markers that, the use of which does not require mutant (auxotrophic) strains, but which can be used directly in wild type strains.
[0056] Optional further elements that may be present in the nucleic acid constructs of the invention include, but are not limited to, one or more leader sequences, enhancers, integration factors, and/or reporter genes, intron sequences, centromers, telomers and/or matrix attachment (MAR) sequences. The nucleic acid constructs of the invention may further comprise a sequence for autonomous replication, such as an ARS sequence. Suitable episomal nucleic acid constructs may e.g. be based on the yeast 2μ or pKD1 (Fleer et al., 1991, Biotechnology 9: 968-975) plasmids. Alternatively the nucleic acid construct may comprise sequences for integration, preferably by homologous recombination (see e.g. WO98/46772). Such sequences may thus be sequences homologous to the target site for integration in the host cell's genome. The nucleic acid constructs of the invention can be provided in a manner known per se, which generally involves techniques such as restricting and linking nucleic acids/nucleic acid sequences, for which reference is made to the standard handbooks, such as Sambrook and Russel (2001) “Molecular Cloning: A Laboratory Manual (3rd edition), Cold Spring Harbor Laboratory, Cold Spring Harbor Laboratory Press, or F. Ausubel et al, eds., “Current protocols in molecular biology”, Green Publishing and Wiley Interscience, New York (1987).
[0057] In a further aspect the invention relates to fermentation processes in which the transformed host cells of the invention are used for the conversion of a lignocellulose or (hemi-)cellulose substrate. A preferred fermentation process is an aerobic fermentation process. The fermentation process may either be a submerged or a solid state fermentation process.
[0058] In a solid state fermentation process (sometimes referred to as semi-solid state fermentation) the transformed host cells are fermenting on a solid medium that provides anchorage points for the fungus in the absence of any freely flowing substance. The amount of water in the solid medium can be any amount of water. For example, the solid medium could be almost dry, or it could be slushy. A person skilled in the art knows that the terms “solid state fermentation” and “semi-solid state fermentation” are interchangeable. A wide variety of solid state fermentation devices have previously been described (for review see, Larroche et al., “Special Transformation Processes Using Fungal Spores and Immobilized Cells”, Adv. Biochem. Eng. Biotech., (1997), Vol 55, pp. 179; Roussos et al., “Zymotis: A large Scale Solid State Fermenter”, Applied Biochemistry and Biotechnology, (1993), Vol. 42, pp. 37-52; Smits et al., “Solid-State Fermentation-A Mini Review, 1998), Agro-Food-Industry Hi-Tech, March/April, pp. 29-36). These devices fall within two categories, those categories being static systems and agitated systems. In static systems, the solid media is stationary throughout the fermentation process. Examples of static systems used for solid state fermentation include flasks, petri dishes, trays, fixed bed columns, and ovens. Agitated systems provide a means for mixing the solid media during the fermentation process. One example of an agitated system is a rotating drum (Larroche et al., supra). In a submerged fermentation process on the other hand, the transformed fungal host cells are fermenting while being submerged in a liquid medium, usually in a stirred tank fermenter as are well known in the art, although also other types of fermenters such as e.g. airlift-type fermenters may also be applied (see e.g. U.S. Pat. No. 6,746,862).
[0059] Preferred in the invention is a submerged fermentation process, which is performed fed-batch. This means that there is a continuous input of feed containing a carbon source and/or other relevant nutrients in order to improve protein yields. The input of the feed can, for example, be at a constant rate or when the concentration of a specific substrate or fermentation parameter falls below some set point.
[0060] Further comprised in the invention is the use of an active protein according to the invention for modification of raw carbohydrate substrate (lignocellulose or (hemi-)cellulose). Preferably said use encompasses hydrolysis of the carbohydrate substrate. Also included in this use is the modification of the substrate by the active protein, thereby allowing other carbohydrate substrate hydrolyzing enzymes to approach the substrate more easily and exert their function in resulting in improved hydrolysis.
EXAMPLES
Examples
Expression of Genes Encoding Lignocellulose and/or (Hemi-)Cellulose Active Proteins in Aspergillus niger
[0061] In order to unambiguously establish that the discovered proteins aid to the increased saccharification of beta-glucan containing plant derived substrates, a host naturally not expressing these genes was (co-)transformed with the respective genes under control of a suitable promoter.
(I) Gene Design
[0062] Synthetic (codon-optimized) full length gene copies from two selected Podospora anserine genes were generated
CAP 61309: CBM1 Protein
[0063] A synthetic gene was designed by back translation from the reannotated protein for further reference called CAP61309, originally deposited under number XM — 001903499.1, with codon bias for Aspergillus niger . The start codon of the protein is part of a BspHI site, so as to fit to the NcoI cloning site of vector pAN52-5doubleNotamdS. At the 3′ end of the gene two consecutive stop codons were introduced, followed by a BamHI cloning site.
[0000]
KpnI BspHI
1
GGTACCTC ATG AAGTTCCACGTCCTCTCCGGCCTCGTCGCCCAGGTCCTCTCCGTTAGCG
1
M K F H V L S G L V A Q V L S
61
CCGGCACCATTCTCTGGGATGGCCGCTTCAACGATATGACCTCCTCCGCCGATCTCAACA
18
A G T I L W D G R F N D M T S S A D L N
121
AGTGGTCCTGGGGCAACCAGGTCGGCCCCTACCAGTACTATATCCACGGCTCCTCCCCGG
38
K W S W G N Q V G P Y Q Y Y I H G S S P
181
TGTCCGCCTACGTCAACCTGTCCCCCGATTACAAGAACCCCGCCGATACCGGCTCCCGCC
58
V S A Y V N L S P D Y K N P A D T G S R
241
AGGGCGCCAAGATCACCCTCGATAACACCGCCTACTGGAACGGCCAGAACATGCGCCGCA
78
Q G A K I T L D N T A Y W N G Q N M R R
301
CCGAGCTGATCCCCCAGACTACCGCCGCTATCAACCAGGGCAAGGTCTACTACCACTTCA
98
T E L I P Q T T A A I N Q G K V Y Y H F
361
GCCTCATGCGCAAGGATATCAACGCCCCTGCCACCACCCGCGAGCACCAGATCGCTTTCT
118
S L M R K D I N A P A T T R E H Q I A F
421
TCGAGTCCCACTTCACCGAGCTGAAGTCCGGCTGGCTCTCCGGCGCTCCCGGCATCTCCG
138
F E S H F T E L K S G W L S G A P G I S
481
ATACCCTGCTCCGCTGGTGCGTCGGCGGCCAGACCCAGTGGTCCGTCGAGTGGGCCGCTG
158
D T L L R W C V G G Q T Q W S V E W A A
541
ATGTCTGGCACAACGTCGCCTACGAGATCGATTTCGCCGCTGGCACCGTCGGTTTCTGGC
178
D V W H N V A Y E I D F A A G T V G F W
601
ACTCCACCGGCTCCGACCCCCTCACCCGCAAGGTCGCCCCCGTCAAGACCAGCACCAGCT
198
H S T G S D P L T R K V A P V K T S T S
661
CCAACGGTGCTGACTGGCACGTCGGCGTCCTCGAGCTGCCCCGCTCCGGCTACCCCGATT
218
S N G A D W H V G V L E L P R S G Y P D
721
CCAACGAGGATTTCTACTGGTCCGGCGTCTACATCGAGTCCGGCTCCCTCACCACCTCCG
238
S N E D F Y W S G V Y I E S G S L T T S
781
TCGCTGGTCCTGGCCAGCCCATCCCTGGTGACGGCGGCTCCTCCAGCTCCAGCTCCTCCT
258
V A G P G Q P I P G D G G S S S S S S S
841
CCTCCGTCCCTTCCTCCACCTCCACCCGCGTGTCCAGCACCTCCACCCCTGCCCCCGTGT
278
S S V P S S T S T R V S S T S T P A P V
901
CCTCCACAACCCTCGTTACCAGCACCACTCGCGTCAGCTCCACCTCTACCTCCAGCGCCG
298
S S T T L V T S T T R V S S T S T S S A
961
CTCCCGTCCAGACCACCCCCTCCGGCTGCACCGCTGGCCAGTACGCCCAGTGCGACGGCA
318
A P V Q T T P S G C T A G Q Y A Q C D G
1021
TCGGCTTCTCCGGCTGCAAGACCTGCGCCGCTCCCTACACCTGCAAGTACGGCAACGATT
338
I G F S G C K T C A A P Y T C K Y G N D
BamHI SacI
1081
GGTACTCCCAGTGCCTC TGATGA GGATCCGAGCTC
358
W Y S Q C L * *
CAP 68330 DUF1996-CBM1 Protein
[0064] A synthetic gene was designed by back translation from the reannotated protein, for further reference called CAP68330, deposited originally under number XM — 001907623.1, with codon bias for Aspergillus niger . Since the start of the coding sequence thus obtained (MHSRN . . . ) cannot be comprised in a restriction enzyme recognition site that is compatible with NcoI (that serves as the 5′ cloning site in vector pAN52-5doubleNotamdS) it was decided to include at the 5′ end of the synthetic gene the 3′ end of the Aspergillus specific gpdA promoter sequence (from SalI to NcoI). SalI is the nearest unique site upstream of NcoI in vector pAN52-5doubleNotamdS.
[0065] At the 3′ end of the gene two consecutive stop codons were introduced, followed by a BamHI cloning site.
[0000]
KpnI SalI
1
GGTACCGTCGACCCATCCGGTGCTCTGCACTCGACCTGCTGAGGTCCCTCAGTCCCTGGT
61
AGGCAGCTTTGCCCCGTCTGTCCGCCCGGTGTGTCGGCGGGGTTGACAAGGTCGTTGCGT
121
CAGTCCAACATTTGTTGCCATATTTTCCTGCTCTCCCCACCAGCTGCTCTTTTCTTTTCT
181
CTTTCTTTTCCCATCTTCAGTATATTCATCTTCCCATCCAAGAACCTTTATTTCCCCTAA
241
GTAAGTACTTTGCTACATCCATACTCCATCCTTCCCATCCCTTATTCCTTTGAACCTTTC
301
AGTTCGAGCTTTCCCACTTCATCGCAGCTTGACTAACAGCTACCCCGCTTGAGCAGACAT
361
CACC ATG CACTCCCGCAACGTCCTCGCCGCTGCCGTCGCTCTCGCTGGCGCCCCTTCCGT
1
M H S R N V L A A A V A L A G A P S V
421
CCACGCCGTCCTCCGCTTCAGCTGCTCCGAGCTGGTCACCGAGCGCCTCGACCCCCTCGT
20
H A V L R F S C S E L V T E R L D P L V
481
GTTCCCTGGCGCCATGCAGTCCCCCCACGTCCACCAGATCGTCGGCGGCAACATGTTCAA
40
F P G A M Q S P H V H Q I V G G N M F N
541
CGTCACTATGGACCCCAACCGCCACAACATCGGCGAGGAAGCCACCTGCACCACCTGTAC
60
V T M D P N R H N I G E E A T C T T C T
601
CTTCTCCGAGGATTTCTCCAACTACTGGACCGCCATCCTCTACTTCCGCGCTCGCAACGG
80
F S E D F S N Y W T A I L Y F R A R N G
661
CACCCTCATCCGCGTCCCCCAGCGCCCCAATATCGATTTCGATGGCGCTCGCGGCGGTGG
100
T L I R V P Q R P N I D F D G A R G G G
721
CATGACCGTCTACTACACCGCCACCTACCAGAACCACAAGCCCACCGCCTTCCAGCCCGG
120
M T V Y Y T A T Y Q N H K P T A F Q P G
781
CTTCCGCATGATCGTCGGCAACCCCATGTACCGCACCCAGGCCGAGGCTTCCCGCTACCG
140
F R M I V G N P M Y R T Q A E A S R Y R
841
CCAGATGACCTTCACCTGCCTCGAAACCCTCTCCACCCGCACCGGCGAAACCACCGAGAT
160
Q M T F T C L E T L S T R T G E T T E M
901
GCCCAAGCAGCCCTGCCGCGAGGGCATCATGTCCAACGTCCGCTTCCCCACCTGCTGGGA
180
P K Q P C R E G I M S N V R F P T C W D
961
TGGCAAGACCCTCGATCCCCCCGATCACTCCTCCCACGTCGCCTACCCGTCCTCCGGCAC
200
G K T L D P P D H S S H V A Y P S S G T
1021
CTTCGAGTCCGGCGGTCCCTGCCCTGCTTCCCACCCTGTCCGCATCCCCCAGCTGTTCTA
220
F E S G G P C P A S H P V R I P Q L F Y
1081
CGAGGTCCTCTGGGATACCCGCCGCTTCAACGATCGCTCCCTCTGGCCCGAGGATGGCTC
240
E V L W D T R R F N D R S L W P E D G S
1141
CCAGCCCTTCGTCTGGTCCTACGGCGATTACACCGGCTACGGCACCCACGGCGATTACGT
260
Q P F V W S Y G D Y T G Y G T H G D Y V
1201
GTTCGGCTGGAAGGGCGATTCCCTCCAGCGCGCTATGGATGCCAACTGCGATTTCTACTG
280
F G W K G D S L Q R A M D A N C D F Y C
1261
CCCCCAGCTCAAGACCCAGTCTATCGCCACCGGCAACCAGTGCCGCCAGAACCAGAAGGT
300
P Q L K T Q S I A T G N Q C R Q N Q K V
1321
CGCCGAGAACATCGATGGCCCCTTCGATCGCCTCCCTGGTAACGTCGAGATCACCGGCCC
320
A E N I D G P F D R L P G N V E I T G P
1381
TCAGCCTGGCGCCTCCAACCCCAACCCCGGCAATGGCGGTGGCTCTACTCAGACTCCTGT
360
Q P G A S N P N P G N G G G S T Q T P V
1441
CCAGCCCACCCCCGTCCCTAACCCTGGCAACGGTGGCGGCTGCTCCGTCCAAAAGTGGGG
380
Q P T P V P N P G N G G G C S V Q K W G
1501
CCAGTGCGGCGGTCAGGGCTGGTCCGGTTGCACCGTCTGCGCCTCCGGCTCCACCTGCCG
400
Q C G G Q G W S G C T V C A S G S T C R
BamHI SacI
1561
CGCTCAGAACCAGTGGTACTCCCAGTGCCTC TGATGA GGATCCGAGCTC
420
A Q N Q W Y S Q C L * *
(II) Overexpression of Synthetic Genes Copies
[0066] The synthetic gene copies were inserted in an expression vector based on the A. nidulans gpdA promoter, carrying also the amdS selection marker. This Aspergillus expression vector pAN52-4-amdSdoubleNotI was derived by cloning the Aspergillus selection marker amdS and an additional NotI cloning site into the Aspergillus expression vector pAN52-4 (EMBL accession #Z32699).
[0067] The resulting expression vectors were introduced in a protease deficient A. niger host strain AB1.13 (Punt et al., 2008). AmdS+ transformants were selected using acrylamide selection.
(III) Protocol MicroTiterPlate Cultivation of Aspergillus
[0068] For cultivation of the strains, standard round bottom 96-well microtiter plates (Corning #3799) were used using a Multitron shaker (Infors) designed for the use with MTP.
[0069] Volume: 200 μl MM Aspergillus medium per well (MM+casamino acids+vitamins)
Each separate well was inoculated with spores (from colonies on plates), using toothpicks. MTP was incubated for 48 hours at 33° C., 850 rpm Good growth was confirmed by visual inspection MTP was centrifuged 10 min 3500 rpm to allow biomass separation.
(IV) DNS-CMCase Method in MTP
Reagents:
[0073] Carboxymethyl cellulose sodium salt (CMC), Avicel or non soluble cellulose 3-5, dinitrosalicylic acid, sodium salt (DNS)
[0000] Potassium/sodium tartrate (tetrahydrate)
Sodium hydroxide
Glacial acetic acid
Reagent preparation protocol:
1. 0.05M NaAc, pH 4.8: Add 2.85 ml of glacial acetic acid to 900 ml of distilled water, adjust the pH to 4.8 with 50% Sodium hydroxide. Bring to total volume of one liter with distilled water. 2. 1% CMC substrate solution: Add 1 gm CMC to 99 ml NaAc buffer, pH4.8. Keep at 4° C. for at least 1 hour before using. The solution is stable for 3 days at 4° C. 3. 10.67% (w/v) Sodium hydroxide solution: add 32 gm of sodium hydroxide pellets to 300 ml of distilled water. 4. 1% 3-5, dinitrosalicylic acid, sodium salt (DNS): suspend 2 gram of DNS in 100 ml of distilled water and gradually add 30 ml of the 10.67% sodium hydroxide solution while mixing. Warm the suspension in water bath set at 50° C. until the solution is clear. Gradually add 60 gm of potassium/sodium artrate (tetrahydrate) to the solution with continuous mixing. Dilute the solution to 200 ml with distilled water. The solution is stable for 2 months. The solution must be clear when used.
Assay Procedure Protocol:
[0078] Making Standard Curve
[0079] Choose a lot of cellulase preparation as a standard
[0080] Standard Curve: dilute the standard using acetate buffer such that the absorbance (at 540 nm) is between 0.1 and 0.5.
[0081] Blank solution: use acetate buffer 0.05M NaAc, pH 4.8 as a blank solution
1. Mix 10 μl of each sample with 90 μl buffer 0.05M NaAc, pH 4, 8 using a 1.1 ml volume, 96-deep well Micro Titer Plate (Oxygen; cat. no. P-DW-11-C). At the same time prepare the standard in the same MTP in duplicate. 2. pre-equilibrate the CMC substrate in a (plastic test plate) in a water bath set at 50° C. for 5 minutes 3. At 20 second intervals, add 100 μl of the CMC substrate (pre-equilibrated at 50° C.) to the enzyme dilution using a multichannel pipette (12 channel). Mix and incubate at 50° C. for 10 minutes. (Incubation time can be adjusted depending on activity level of parental strain). 4. at the same time interval as in step 3, add 300 μl of DNS solution and mix 5. boil the reaction mixture+DNS for exactly 5 minutes by placing the test microtiterplate in a boiling water bath. Cover the tops to prevent evaporation during boiling. As a blanc for remaining glucose in the samples prior to incubation also a duplicate MTP is included in which the reaction is terminated by boiling directly upon addition of the cellulase substrate. All samples, standard and blanks should be boiled together. After boiling, cool the plate in an ice bath 6. Measure the absorbance of the enzyme samples, standard and blancs at 540 nm in a Tecan Infinite 200 microplate reader
(Measurement range 0-3 OD)
(V) Cellulose Binding Assay
[0089] For qualitative evaluation of cellulose binding capacity the following assay was used:
Incubate 1 ml fermentation samples 1 hour with 10 mg Avicel at 4° C. with gentle mixing. Centrifuge 10 min, 3000 g Wash the cellulose once with 0.5 ml of 50 mM sodium phosphate pH 7.0 Elute the bound protein by boiling the cellulose pellet for 10 min in 50 μl of 10% SDS Subject 20 μl to SDS-PAGE gel.
(VI) Transformant Screening
[0095] For a number of transformants obtained from each of the two expression vectors described MTP cultures were performed.
[0096] For both the CAP68330 and CAP61309 transformants the culture supernatant was used in a DNS-CMCase activity assay to identify the transformants with the highest activity level. For each expression vector transformants with increased CMCase activity were identified.
(VII) Fermentation
[0097] Transformants selected from the transformant screening were cultivated in standard fed-batch fermentation and the lignocellulose and/or (hemi-)cellulose active proteins produced were analyzed in various cellulase related assays
[0000] VIII Analysis of A. niger Transformants in Controlled Fermentation
[0098] Medium samples during the various fermentations were taken and samples at the end of fermentation (around 70-100 h) were analyzed for cellulase related activity using both soluble (CMC) and non-soluble (non-soluble cellulose, avicel) cellulase substrates. In addition, as the produced CAP68330 or CAP61309 proteins could also be non-enzymatic accessory proteins potentiating cellulase activity also an assay was performed in the presence of a fixed amount of a commercial cellulase preparation and samples from the culture fluid of the CAP68330 and CAP61309 strains was added
[0099] Results of these assays are shown in the table below
[0000]
Substrate
non-soluble cellulose
Avicel
Strains
CMC
−cellulase
+cellulase
−cellulase
+cellulase
Blanc
ND
ND
0.07
ND
1.00
cap68330#4
0.25
0.15
0.26
1.92
2.06
cap61309#8
0.22
0.21
0.23
1.90
2.09
CONTROL
0.31
0.17
0.21
1.53
1.86
[0100] As shown in the table the activity towards CMC and non-soluble cellulose was not increased compared to the control strain not expressing CAP68330 or CAP61309 protein. The background activity level observed in the Control strain originates from native Aspergillus proteins releasing reducing sugar equivalents from the various substrates.
[0101] In contrast as shown in the table, with Avicel as a substrate the cellulase-related activity was higher for the CAP68330/61309 strains than for the control, indicating the presence of cellulase and/or cellulase enhancing activity due to the presence of the CAP68330 or CAP61309 protein.
IX SDS PAGE and Cellulose Binding Analysis
[0102] In addition to activity assays also SDS PAGE was carried out with concentrated fermentation samples. In addition cellulose binding analysis followed by SDS PAGE analysis was carried out. As shown in FIG. 1 for CAP61309 protein an additional protein band was observed in SDS PAGE. This band was also identified by binding to Avicel | Methods to digest carbohydrates, especially lignocelluloses and hemicelluloses, using fungal proteins previously not recognized as having this activity are described. | 2 |
[0001] This application claims priority under 35 U.S.C. § 119 to U.S. provisional application No. 60/743,242, filed 7 Feb. 2006, the entirety of which is incorporated by reference herein.
BACKGROUND
[0002] 1. Field of Endeavor
[0003] The present invention relates to devices, systems, and processes useful for dispensing potable liquids, and more specifically to dispensing potable liquids from small containers with gravity.
[0004] 2. Brief Description of the Related Art
[0005] Many potable liquids significantly oxidize upon exposure to air. While in some cases this may be advantageous, oxidation of many such liquids makes the drink less palatable, and is therefore to be avoided. For example, fruit wines, especially grape wines, are known to oxidize significantly once exposed to unlimited amounts of oxygen, such as when the closure (cork, screw top, and the like) is removed from a typical 750 ml wine bottle. While it is known that a small amount of oxygen is transported through a natural cork bottle closure, resulting in a very slow exposure of the wine to oxygen, more hermetic closures, such as screw tops, permit essentially no oxygen to contact the wine. Once the bottle is opened, however, oxidation of the wine (or, more accurately, of components of the wine) commences.
[0006] In the past there have been several ways proposed to deal with the inevitable degradation of the perceived quality of wine once a bottle has been opened. Of course, consuming the entire contents of the bottle before it is unpalatable is one course of action; other, more temperate measures have also been proposed. Devices have been proposed which permit a partial vacuum to be formed in the partially emptied wine bottle, with a replacement closure sealing the bottle neck; while removing some of the air from the bottle, air is still present in the bottle, however, and thus oxidation continues.
[0007] It has also been prevalent to inject an inert, non-oxygen-containing, food-grade gas into the opened, partially full bottle. The inert gas effectively takes the place of the air (sparges) in the bottle. At the same time, prior systems have typically relied on the pressure of the inert gas to dispense the wine from an upright bottle, thus requiring a dip tube extending to the bottom of the bottle. While useful in some environments, such systems require: large gas cylinders; the bottles to remain upright so that the dip tubes are guaranteed to be positioned in wine; the high pressures required for dispensing can be damaging to the wine; the required high pressures are difficult to maintain in the bottle, thus requiring very robustly attached closures. Such systems are therefore not suitable for home use.
[0008] There remains a need, therefore, for improvements in systems, devices, and methods which address these and other shortcomings in the prior art.
SUMMARY
[0009] According to a first aspect of the invention, a wave washer comprises a disk, an opening in the disk, a lever extending from the disk, and undulations formed in the disk.
[0010] According to another aspect of the present invention, a bottle head comprises a valve having a valve stem, a fluid passage, and a dispensing port in fluid communication with the fluid passage, a seal portion extending from said valve, the fluid passage passing through the seal portion, at least one seal positioned around the seal portion, a movable element on the seal portion and adjacent to the at the least one seal, and at least one wave washer positioned on said seal portion between said movable element and said valve.
[0011] According to yet another aspect of the present invention, a system useful for storing and dispensing a potable liquid from a bottle having a neck comprises a cabinet having an inclined surface and at least one opening configured and arranged to receive the neck of a bottle, a gas source of inert, non-oxygen containing gas, a pressure regulator in fluid communication with said gas source, a gas line in fluid communication with the pressure regulator, at least one bottle head configured and arranged to form a fluid seal when positioned in the neck of the bottle, the at least one bottle head including a gas passage and a fluid passage, wherein the gas line is in fluid communication with the gas passage of the at least one bottle head.
[0012] Still other aspects, features, and attendant advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description of embodiments constructed in accordance therewith, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention of the present application will now be described in more detail with reference to exemplary embodiments of the apparatus and method, given only by way of example, and with reference to the accompanying drawings, in which:
[0014] FIG. 1 a illustrates a front elevational view of an exemplary embodiment of a potable liquid preservation and dispensing system in accordance with principles of the present invention.
[0015] FIG. 1 b illustrates a side elevational view of the system of FIG. 1 a.
[0016] FIG. 2 illustrates portions of the system of FIG. 1 a.
[0017] FIG. 3 a illustrates top plan view of portions of the system of FIG. 1 a.
[0018] FIG. 3 b illustrates a front elevational view of portions of the system of FIG. 1 a.
[0019] FIG. 4 a illustrates an enlarged elevational view of an exemplary head of the system of FIG. 1 a.
[0020] FIG. 4 b illustrates the head of FIG. 4 a in a second configuration.
[0021] FIG. 4 c illustrates portions of the head of FIG. 4 a.
[0022] FIG. 4 d illustrates a top plan view of an exemplary force transmission unit in accordance with principles of the present invention.
[0023] FIG. 4 e illustrates a side elevational view of the unit of FIG. 4 d.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0024] Referring to the drawing figures, like reference numerals designate identical or corresponding elements throughout the several figures.
[0025] FIG. 1 illustrates front ( FIG. 1 a ) and side ( FIG. 1 b ) elevational views of a storage and dispensing system 10 embodying principles of the present invention. A cabinet 12 is illustrated having a bottom storage area 14 including, by way of non-limiting example, four compartments that are sized and configured to hold one or more (eight are illustrated) containers of a potable liquid. Without being limited to any single potable liquid, some aspects of the present invention, as described in greater detail below, are particularly advantageous when the potable liquid is wine and the containers are bottles B, e.g., glass bottles, e.g., 750 ml wine bottles.
[0026] A top portion 16 of the cabinet 12 includes a positioning and dispensing tray 18 , which has a generally open top 20 and one or more slots 22 . The slots are sized to accept the neck of a typical 750 ml glass wine bottle, although other sizes, selected to similarly accommodate other sized liquid containers, may alternatively be provided. The top portion 16 includes a slanted support surface 24 so that one or more bottles of liquid can be supported with the neck N of the bottle B in a slot, so that the potable liquid contents of the bottle can flow out of the bottle by gravity. Preferably the bottle B, and optionally each bottle, that is supported in the top portion 16 of the cabinet 12 includes a dispensing head 30 , such as that illustrated, which seals the neck of the bottle and permits a user of the system to selectively dispense the potable liquid from the bottle into, e.g., a glass G.
[0027] FIG. 2 illustrates a right side elevational view of a portion of the system 10 . The bottle head 30 is installed in the bottle neck N, as described above. A compressed gas cylinder 32 is provided in a separate space in the cabinet, and includes a pressure regulator 34 . The gas in the cylinder is a food grade inert gas that does not significantly react with the potable liquid in the container(s); when the potable liquid is wine or another liquid that is negatively affected by prolonged contact with oxygen, the inert gas is preferably nitrogen. As described in greater detail below, the inert gas cylinder 32 is in fluid communication, via the pressure regulator 34 , with the dispensing head 30 to slightly pressurize the contents of the container, and more advantageously to sparge air (and other gases) from the container and replace it with the inert gas. In this manner, the potable liquid contents of the container are at least partially preserved, despite the fact that the container's original closure (e.g., a cork or screw cap) has been removed and air had been allowed to fill the dead space in the container, because the inert gas blankets the potable liquid and inhibits or prevents contact with other gases (such as oxygen). One of numerous commercially available regulators usable as regulator 34 is model NR-30 by Nippon Transan Gas Co. LTD, through its US affiliate, Leland Limited (South Plainfield, N.J.); others are also available and usable. Several of numerous commercially available inert gas cylinders usable as cylinder 32 are available from Nippon Transan Gas Co. LTD, in their Mini Gas Cartridge line, including the LPG-type cylinder (also available through Leland); other suitable containers are available from NitroTap, LTD (Warren, R.I.).
[0028] FIG. 3 illustrates top plan ( FIG. 3 a ) and partial front elevational ( FIG. 3 b ) views of an exemplary system 10 in accordance with the present invention. The top portion 16 , including the inclined bottle tray 18 , is illustrated supporting a single wine bottle B and the compressed gas cylinder 32 and the pressure regulator 34 attached to the cylinder. The front face 36 of the top portion 16 preferably includes a cutout or hole 38 through which the base of the cylinder 32 can extend, for easy access and removal, and a pressure gauge 40 , in fluid communication with the pressure regulator, which displays the fluid pressure output by the regulator. A gas distribution tube, manifold, or the like 42 fluidly connects the output of the pressure regulator 34 , the pressure gauge 40 , one or more self-sealing fluid connection ports 44 that are positioned on the front face 36 of the cabinet, and preferably a pressure relief valve 46 positioned at a convenient location on the cabinet. One or more gas injection tubes 48 , preferably flexible, lead from the one or more connection ports 44 to an input port 50 on the head 30 . The port 50 is, when the head 30 is installed in a suitable neck N, in fluid communication with the interior of the bottle via a separate fluid passage 72 .
[0029] Another advantageous aspect of the present invention includes that the connections between the head(s) 30 and the connection port(s) 44 are optionally self-sealing. Thus, when the tube 48 is connected to the port 44 and the input 50 to the head 30 , inert gas flows from the distribution tube 42 , through the port 44 , through the tube 48 , through the head 30 via passage 72 , and into the container B holding the potable liquid. Importantly, each of the portions of the system outside of the cabinet at which this sealed fluid connection can be broken by the user of the system, includes a self-sealing valve or connection element. For example, such a self-sealing element can be located in one or more of: in the head 30 ; at the end of the tube 48 which connects to the head 30 ; at the end of the tube 48 that connects to the port 44 ; and at the port 44 . In one non-limiting example, the tube 48 is securely connected to the head 30 , and the port 44 and the opposite end of the tube 48 each include self-sealing elements. In another non-limiting example, the tube 48 is securely connected to the port 44 , and the head 30 and the opposite end of the tube 48 each include self-sealing elements.
[0030] FIG. 4 (including FIGS. 4 a - 4 e ) illustrates several views of an exemplary bottle head 30 embodying principles of the present invention. The head 30 is sized to fit into and selectively seal against the inner surface of the potable liquid's container, e.g., wine bottle neck N. The head includes a valve V, valve stem S, and liquid outlet port P of conventional constructions, the details of which are well known to those of ordinary skill in the art and are thus not included herein so as to not obscure the invention; one example of these elements is a so-called Tomlinson brand model CBT #1000004 Tap. As well known to those of skill in the art, the outlet port P is in fluid communication with a fluid passage 74 which extends through the head, which is separate from the gas passage 72 . The lower portions of the head, which are shown positioned in the neck of the bottle, includes one or more compression seals, gaskets, or O-rings R which, when compressed, expand outward and form a seal between the head 30 and the interior surface of the bottle neck N, in a known manner. The head therefore includes a number of washers W or similar elements between which the O-rings are positioned, and the bottommost of which is fixed relative to the rest of the head. A sleeve or ferrule 52 is positioned above the topmost washer and can slide relative to the rest of the head. By moving the head 30 relative to the sleeve 52 , the sleeve pushes down on the topmost washer, which in turn pushes down on and compresses the adjacent O-ring, on down to the washer which is fixed to the head. Thus, moving the top and bottommost parts of the head compresses the O-rings and causes them to seal against the inner surface of the bottle neck N.
[0031] One advantageous aspect of the present invention, which facilitates moving the parts of the head and thus sealing the head in the bottle neck, includes providing a force transmission unit which is accessible to a user of the head and which converts rotary motion of and force on the unit into a downward motion, and therefore force, by the unit. In general terms, the force transmission unit can be embodied in one of numerous devices which operate based on the well-known “inclined plane” configuration, such as screw threads, wedges, cams, including rotary cams, and the like, any of which exert downward motion and force. This downward motion and force is used, in the context of the present invention, for the compression and lateral expansion of the seals described above.
[0032] According to a preferred, yet still exemplary, embodiment, the force transmission unit includes one or a pair of wave washers 60 , illustrated in FIGS. 4 d and 4 e . Each wave washer 60 is generally disk-shaped with a center opening 62 sized to receive corresponding portions of the head 30 therein, but in profile has an undulating shape and includes a lever 64 that projects outward from the disk. More specifically, each wave washer 60 includes high portions 66 and low portions 68 therebetween. While the number of undulations does not restrict the present invention, a small number is preferable to reduce the force required to use the wave washers. As illustrated in FIGS. 4 a and 4 b , two wave washers 60 are positioned around the middle of the head 30 , above the sleeve 52 , with the washers' levers 64 adjacent to, but preferably not overlapping, each other, and the washers' undulations 66 , 68 mated together; in this configuration, the two wave washers have a thin profile. An expanded profile of the two wave washers 60 is achieved by rotating one of the wave washers relative to the other (clearly, both washers can be simultaneously rotated) around the longitudinal (up-down) axis of the head 30 , which causes the adjoining surfaces of the two wave washers to slide against each other toward an anti-nested orientation, in which upward extending undulations 66 of the lower washer are vertically aligned with and touch downward extending undulations 68 of the upper washer, and vice versa. Thus, when the wave washers 60 are rotated the distance of one undulation, the washers move apart (or toward) each other the height of one of the wave washers, pushing on the adjacent portions of the head 30 as described above.
[0033] Yet another aspect of the present invention includes that the profile of a wave washer 60 is formed on a portion of the head 30 , e.g., the top of the sleeve 52 or the bottom of the adjoining upper portion 70 of the head, and only one rotatable wave washer 60 is positioned adjacent thereto.
[0034] The two wave washers 60 , positioned between the top portion of the head 30 and the top of the sleeve 52 , thus can be used to quickly move the sleeve down relative to the rest of the head, and thus expand the O-rings R against the bottle neck N. The present invention is not limited to the use of wave washers 60 , however, and more conventional force-fit compression fittings, with typical flexible fins, a cam-style lever, and screw thread-and-nut configurations are also alternatively used.
[0035] One advantage of the present system is that it does not require refrigeration to preserve the potable liquid in the container. According to other aspects of the present invention, the cabinet 12 can be constructed to include a coolant system that cools the containers, in a known manner. Further optionally, the system can be sized and configured to be positioned inside a refrigerator.
[0036] A particularly advantageous aspect of the present invention includes that the individual containers can be removed from the system, e.g., in order to dispense a different liquid, without releasing the inert gas from inside the container. An exemplary method of using the system thus includes: positioning a container having a potable liquid, e.g., wine, therein, in the top portion of the cabinet 12 ; attaching tube 48 to the inlet port 50 of the head 30 , thus fluidly connecting the interior of the container with the inert gas cylinder 32 via the pressure regulator 34 , the distribution line 42 , and the port 44 ; dispensing potable liquid from the container by manipulating the valve V contained in the head 30 , in a known manner; disconnecting the tube 48 from the head 30 and/or from the port 44 ; and removing the container B from the cabinet 12 , now that it is no longer tethered to the cabinet by the tube 48 . Because the head 30 , tube 48 , and/or port 44 each includes a self-sealing element, the inert gas does not escape from the container, the potable liquid is continuously preserved, and a vacuum is not created in the container when liquid is dispensed. A system of the present invention can therefore include more potable liquid containers than can be supported in the top portion of the cabinet, each container fitted with a head 30 , and the containers can be merely swapped out of the cabinet when it is desired to more easily dispense the liquid. Each head 30 thus ‘belongs’ to a container, sealing the container and preserving its potable liquid contents.
[0037] Another advantageous aspect of the present invention includes that open, serviceable wine bottles B are stored in a relatively horizontal position, which compresses their ordinary storage height by about 50%, compared to upright (standing) storage of a wine bottle. This facilitates use and storage of open wine bottles in smaller spaces, such as pullout drawers in conventional kitchen cabinetry, refrigerators, and even specially-constructed sideboard chests. Thus, a slightly neck-down orientation of containers of potable liquids, a ‘ready to dispense’ configuration, is unique and affords many benefits.
[0038] The self-sealing elements described herein are currently commercially available; examples include, but are not limited to: Beswick Engineering Quick Disconnect Couplings QDC-101-I-1012 and QDC-101-E-2PM (Double Shut-off), and Colder Products Couplings PMCD12025 and PMCD2202 (Valved Shutoff).
[0039] Another advantageous aspect of the present invention includes that the pressure regulator 34 maintains the pressure in the system at a low level, e.g., between about 3 and 7 psi, preferably about 5 psi. While this pressure is sufficient to charge the system with inert gas, it differs from typical dispensing systems which use a vertically oriented potable liquid container, a siphon tube in the container, and gas pressures typically around 30 psi. In the system of the present invention, a high gas pressure in the system would result in the liquid contents of the container being sprayed out of the outlet P of the head 30 , and would require a significantly more robust pressure vessel for the insert gas cylinder 3 ; both of these would be significantly less preferred. Pressure regulators capable of maintaining pressure in the system at about 5 psi are currently commercially available and well known to those of ordinary skill in the art.
[0040] While the invention has been described in detail with reference to exemplary embodiments thereof, it will be apparent to one skilled in the art that various changes can be made, and equivalents employed, without departing from the scope of the invention. The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiments were chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and their equivalents. The entirety of each of the aforementioned documents is incorporated by reference herein. | A storage and dispensing system for potable liquids, e.g., wine, includes an inclined rack which holds a bottle with the neck down, a dispensing head sealing the bottle neck, and an inert gas supply system in fluid communication with the head. As liquid is dispensed from the bottle, low-pressure gas is admitted into the bottle, to inhibit oxidation of the wine. The system includes one or more self-sealing elements in the head itself and/or in gas lines between the head and a gas regulator. Because the self-sealing elements prevent air from entering into the system when the gas lines are detached, each bottle can have a dedicated head and bottles can be swapped out for dispensing, without the need for replacing bottle heads, sparging, or using more than one source of gas. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a locking mechanism providing a high degree of security for the container on which it is mounted. More particularly, the present invention relates to a locking mechanism of the type used to secure, maintain, and provide locked security for pivoting doors used on freight containers, trucks, and/or trailers.
Prior locking mechanisms have proven unsatisfactory in regards to providing security to the contents of the container. Because the chain or padlock used in prior locking mechanisms is exposed on the outside surface of the container door, thieves or vandals are able to cut or pry open the locking mechanism.
It is, therefore, an object of the present invention to provide a new and improved locking mechanism which shields the lock from prying or cutting so as to overcome the above mentioned problem which limits the utility of prior door locks. The novel locking mechanism provides enhanced security while maintaining ease of use.
Other objects, and the advantages, of the present invention will be made clear by the following detailed description of a preferred embodiment constructed in accordance with the teachings of the present invention.
SUMMARY OF THE INVENTION
These objects are achieved by providing a door lock mechanism operated and controlled by a locking handle mounted on a pivot pin. Affixed to the handle are one or more locking bars that extend vertically the full length of the door, with the ends engaging locking bar receptacles located on the interior frame of the container. Mounted to one of the locking bars is a catch that moves along with the locking bars such that as the handle is moved to the closed position, the catch passes through the open hasp of a padlock, the padlock being enclosed in a protective housing which both shields the padlock from cutting and prying and which is engaged by the padlock when the handle is moved and which therefore prevents the padlock from vertical movement after the padlock is closed. Once the lock catch is displaced through the open hasp, the padlock hasp is closed and the padlock, catch, and consequently the locking bar are all prevented from movement. The entire locking mechanism is protected by an enclosure formed by a structural frame and the structural frame can be attached to the door of a freight container, truck trailer, or other container and, when attached to such a container, only one end of the handle and the end of the padlock into which the key is inserted to unlock the padlock are exposed.
In another aspect, the present invention provides a method of locking a pivoting handle in a fixed closed position using a locking mechanism comprised of the handle, a locking bar, a lock catch mounted to the locking bar, a padlock, and a protective housing. The method comprises the steps of positioning the padlock in the protective housing with the hasp open, pivoting the handle in a first direction so that the locking bar is moved along with the handle and the attached catch travels through the open hasp of the padlock, and forcing the padlock into the protective housing to close and lock the padlock around the catch. When closed and locked around the catch in this manner, the padlock engages the protective housing to resist pivoting of the handle in the second direction and consequent movement of the locking bar.
In a particularly preferred embodiment of the method of the present invention, the handle, locking bar, catch, padlock, and protective housing are mounted to the door of a container and the locking bar is moved into and out of engagement with structure on the container when the handle is moved in the first and second directions to resist and allow opening of the door of the container.
As noted above, a principal advantage of the locking mechanism of the present invention is the limited exposure of the padlock to potential thieves. The housing of the padlock, together with the structural frame, encloses the entire locking mechanism, thereby preventing thieves and vandals from being able to grasp the padlock to cut or pry it open. Further, this advantage is obtained while maintaining the ease of use of the door and locking mechanism.
Another advantage of the locking mechanism of the present invention is provided by the shape of the protective housing. Because the only access to the padlock is from the end, or bottom, of the padlock into which the key is inserted, it is not possible to grasp the hasp of the padlock to assist in closing the padlock to lock the locking mechanism. Consequently, the protective housing is shaped so that force exerted on the end of the padlock into which the key is inserted causes the hasp of the padlock to close and lock around the catch extending therethrough.
Other advantages of the present invention will be made clear to those skilled in the art by the following description of a presently preferred embodiment thereof, it being understood that this description is being provided for purposes of exemplification and that other embodiments can be constructed in accordance with the teachings of the present invention which function to achieve those same advantages but that due to limitations of practicality and brevity, and the requirements of the Patent Statute, only the preferred embodiment is described.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 an elevational view of the end of a typical container of the type used for shipping containerized freight showing the doors and a locking mechanism of a type known in the art. The components of the locking mechanism of the type known in the art are all external to the container.
FIG. 2 is an elevational view a container similar to the container of FIG. 1 having the locking mechanism of the present invention installed thereon. The only components of the locking mechanism which are exposed to the exterior of the container are the butt end of the locking handle and the key end of the padlock.
FIG. 2a is an exploded view of a portion of the frame of the container of FIG. 2 showing the lower locking bar receptacle which the doors of the container engage to lock the doors in their closed position.
FIG. 3 is a detailed front elevational view of the locking mechanism of FIG. 2 showing a portion of the front protective plate of the locking mechanism cut away to show the details of construction thereof.
FIG. 4 is a perspective view of the locking mechanism of FIG. 2 shown from the inside of the container and with a portion of the rear plate of the structural frame of the enclosure of the locking mechanism cut away.
FIG. 5 is a perspective view of the locking mechanism with a portion of the enclosure for the locking mechanism cut away.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A freight container having a typical latching and locking mechanism of a type known in the art is shown in FIG. 1. The typical configuration involves one or more locking bars 16, the movement of which is controlled by a locking handle 18. The locking bars are guided by brackets 20 attached to the exterior surface of the door 12 and which guide the locking bars into the locking hasps 14 attached to the frame 11 of the storage container 10 to secure the door 12 in a closed position. Once secured, known locking mechanisms lock the door in the closed position by use of a padlock or chain attached to the handle in such a way as to prevent further movement of the handle. All of the components of such prior mechanisms, including the lock, are exposed on the outside surface of the door. Thus, thieves or vandals have easy access to the components of the lock mechanism and can therefore gain access to the contents of the storage container.
Referring to FIG. 2, a preferred embodiment of the door lock mechanism of the present invention is indicated generally at numeral 22. Locking mechanism 22 is comprised of a structural frame, indicated generally by numeral 28, which is inset into the door 12 of the storage container 10. Insetting the enclosure into the door in this manner encloses all of the components of the locking mechanism of the present invention, including the locking bars 16 and their respective locking bar receptacles which are located on the door frame 11 of storage container 10.
FIG. 2a shows a detailed exploded view of the lower locking bar receptacle 48 which is engaged by the lower end of the elongate locking bar 16 when the doors are latched in the closed position. The locking bar receptacles are comprised of slots 50 cut in the upper and lower interior door frame 11 and "U"-shaped channels 52 mounted in slots 50. Alternatively, hasps attached to the interior frame can be used to receive and hold the locking bars in place in the manner known in the art. However, hasps lack the principle advantage of the locking bar receptacles 48 of the preferred embodiment shown in that they are located on the outside of the container and therefore susceptible to attack in the event it is desired to break into the container.
The locking bar receptacles 48 of the preferred embodiment confer an additional advantage on the locking mechanism of the present invention. Specifically, as the ends of locking bars 16 are raised or lowered into the "U"-shaped channel 52 by moving handle 24 in the manner described below, if the locking bars are not properly aligned for insertion, the force imposed by the channel on the portion of the frame surrounding the slot 50 enables the frame to flex enough to securely receive the locking bars 16. Because the containers used for shipping freight by land, air, and sea experience significant wear and tear through repeated use, the advantage achieved by the locking bar receptacles 48 to enable secure closing is substantial.
FIGS. 3 and 5, respectively, provide a front elevational and a front perspective view of the individual components of the locking mechanism 22. Both views are shown with a portion of the enclosure formed by structural frame 28 cut away. The portion of the frame 28 cut away is the protective plate 30 which sits flush with the exterior surface of the storage container door 12 and which, along with guide plate 40, prevents the door lock mechanism 22 components from being exposed to the exterior of the storage container 10.
The door lock mechanism 22 is controlled by an elongate locking handle 24. The locking handle 24 is affixed to a pivoting pin 26 which is attached to the rear plate 42 of the structural frame 28. One end of locking handle 24 extends through a guide plate 40 which is integral with frame 28 and which limits the range of movement of the locking handle 24 and the other end of handle 24 and pivoting pin 26 are enclosed within frame 28.
Elongate locking bars 16 are pivotally mounted to handle 24 inside frame 28 and extend through holes 17 in frame 28 such that when the handle is moved, the bars are moved vertically into or out of the locking bar receptacles 48. Although the preferred embodiment shown in the figures is provided with two locking bars, one of which is moved upwardly by moving handle 24 and the other downwardly, alternative designs may include a varying number of bars depending on the size of the storage container. Movement of the locking bars 16 is guided in part by the holes 17 cut out of the top plate 46 and the base plate 44 of the structural frame 28. In addition to the holes 17, brackets or other structure (not shown) in the interior of the door 12 can be provided to aid in guiding the ends of the locking bars 16 which extend out of frame 28 into the locking bar receptacles 48 in the manner described above.
Attached to one of the locking bars 16 is an elongate lock catch 32 comprised of a "Z"-shaped bracket which is mounted at the end inside the enclosure formed by frame 28 to the locking bar 16. The long leg of the bracket extends in a direction which is substantially parallel to but spaced apart from the surface of locking bar 16 to form a slot (not numbered) therebetween. As best shown in FIG. 5, the lower portion of catch 32 extends through a slot in a protective housing 34 which is integral with the frame 28 and through the open hasp of a padlock 36 positioned in housing 34. Thus, in the preferred embodiment shown, the lower portion of the catch 32 is an "L"-shaped piece that moves freely through the open hasp 38 of padlock 36 when handle 24 is pivoted. Once hasp 38 is closed around the long leg of catch 32, the bottom leg 33 of the "L"-shaped portion of catch 32 prevents further movement of the catch 32, as well as the locking bar 16 to which catch is mounted and the handle 24 to which locking bar 16 is mounted, by engagement of the body 39 of padlock 36 by the top surface of the bottom leg 33 of catch 32. As best shown in FIG. 3, in the preferred embodiment, the bottom leg 33 of catch 32 extends at an angle to the long leg of catch 32 in a direction which is preferably substantially parallel to the top surface 35 of housing 34. Those skilled in the art who have the benefit of this disclosure will recognize that lock catch 32 can be shaped differently than as shown and described herein as long as the catch moves freely through the open hasp 38 of padlock 36 and structure is provided to accomplish the function of the bottom leg 33 of catch 32, e.g., to interfere with movement of the catch 32 relative to padlock 36 when padlock 36 is closed.
As noted above, attached to the protective housing 34 is the guide plate 40 which is also attached to the top plate 46, bottom plate 44, back plate 42, and protective front plate 30 of the structural frame 28. Thus, none of the mechanical workings of the locking mechanism of the present invention is exposed to the exterior of container 10. Both the base plate 44 and the upper surface 35 of protective housing 34 are provided with slots which allow catch 32 to move through the top surface 35 in the vertical direction. Once the "L"-shaped portion of catch 32 passes through the open hasp 38 of the padlock 36, the key end of the padlock 36 is pushed into the protective housing 34 to close the hasp and lock the device. To aid in closing the hasp 38 of padlock 36, the side walls of the protective housing 34 are curved inwardly so that housing 34 is funnel shaped to conform to the shape of the padlock hasp 38.
Because only the key end of the padlock 36 is exposed to the exterior of the storage container 10, the locking mechanism of the present invention allows the container to be locked and shipped while the keys are shipped separately to those who have rightful access to the container or carried by the person with custody of the container. The padlock 36 may be any conventional padlock of suitable size, shape, and strength and one of the advantages of the locking mechanism of the present invention is that it is capable of being used with a padlock which is supplied by the shipper in accordance with customary procedures in the shipping industry.
Referring to FIG. 4, the preferred embodiment is shown from inside the container 10. The rear plate 42 of frame 28 has been cut away to show the construction of the locking mechanism, but in the preferred embodiment is flush with the inside surface of the container door 12. Additionally, rear plate 42 is attached to the base plate 44, side plates 45, top plate 46, and guide plate 40 thereby providing structural rigidity to the entire frame 28.
Referring now to FIGS. 2-5, a preferred embodiment of a method of locking a pivoting handle in a fixed closed position will be described. As set out in detail above, the locking mechanism is comprised of the handle 24, a locking bar 16, a lock catch 32 mounted to locking bar 16, a padlock 36, and a protective housing 34, and the method comprises the steps of positioning padlock 36 in the protective housing 34 with the hasp 38 of padlock 36 open. Handle 24 is then pivoted in a first direction so that the locking bar 16 is moved along with handle 24 and the catch 32 affixed to locking bar 16 travels throught the open hasp 38 and padlock 36 is forced into housing 34 to close and lock the padlock around catch 32 so that, when handle 24 is pivoted in the second direction, the padlock 36 engages housing 34 to resist pivoting of the handle 24 and movement of locking bar 16.
Although described in terms of the embodiments shown in the figures, those skilled in the art will recognize from this description that the invention encompasses embodiments other than those which are shown and in which the component parts thereof may be modified without changing the manner in which those parts function to achieve their intended result. All such alternative embodiments are intended to fall within the scope of the following claims. | A locking mechanism used to provide heightened security for storage containers. The locking mechanism uses a padlock to lock the doors, but unlike past inventions the padlock has only limited exposure to the outside of the storage container. This prevents thieves or vandals from being able to pry or break the lock open. Further, the essential components of the locking mechanism are all housed in a protective frame which prohibits tampering with the individual components of the door lock mechanism. | 4 |
BACKGROUND
[0001] Power supplies have long been employed to provide power to electronic devices. For example, most electronic devices require some type of power adaptor arrangement to transform household voltages (e.g., 110 V or 220 V) to the voltage level(s) suitable for charging the batteries and/or operating the electronic components.
[0002] As power adaptor design evolves, the design has become more user-friendly over time. Most power adaptors nowadays enclose the power electronics and/or electrical circuitry in a power adaptor housing. The power electronics and/or electrical circuitry within the power adaptor housing performs the voltage/current transformation tasks to provide the suitable voltage levels for device operation. These voltages/currents are then provided to the electronic device (e.g., a laptop computer or a digital audio/video player) via flexible electrical conductors. The flexible electrical conductors are coupled to pins of a connector plug that is configured to be mated with a corresponding socket in the electronic device.
[0003] This arrangement substantially minimizes the impact on the portability of the electronic device while power is plugged in. For example, a laptop user may continue to move the laptop computer around while being plugged in with relative ease since the laptop is connected to a flexible conductor cable and the bulk of the power electronics of the power adaptor is advantageously disposed further away from the laptop (e.g., on the floor).
[0004] Power adaptors have also evolved to the point where management circuitry is provided to monitor the operation of the power electronics and to respond if changing, dangerous and/or undesirable operating conditions exist. For example, the management circuitry of some power adaptors may allow the adaptor to cease providing power to the electronic device if the power adaptor overheats, for example.
[0005] As users demand more and more sophistication from their electronic devices and accessories, management circuitries and techniques for power supplies continue to improve. This patent application relates to novel and innovative arrangements and techniques for managing power supplies.
SUMMARY
[0006] The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented below.
[0007] The invention relates, in an embodiment, to a management circuit (MC) for a power supply, the power supply being configured to supply a first voltage level and a ground voltage level. The management circuit includes a first MC terminal coupled to a positive supply terminal of the power supply, the positive supply terminal being configured to provide the first voltage level. The management circuit further includes a second MC terminal coupled to a ground terminal of the power supply, the ground terminal being configured to provide the ground voltage level. The management circuit additionally includes a switch and a processor coupled to the switch for controlling the switch. The management circuit also includes a first output terminal, the switch being coupled to the first MC terminal and the first output terminal for controllably providing the first voltage level to the first output terminal. There are also included a first impedance circuit coupled to the second MC terminal and a second output terminal coupled to the first impedance circuit, wherein the processor controls the switch opening and the switch closing responsive to both parameters sensed through the first output terminal and the second output terminal and previous state information pertaining to a present operating state of the management circuit.
[0008] In another embodiment, the invention relates to a method for controlling a power supply, the power supply being configured to supply a first voltage level and a ground voltage level. There is included providing a management circuit having a processor coupled to a switch, the switch being coupled between a first output terminal of the management circuit and a positive supply terminal of the power supply that provides the first voltage level. The processor controls switch opening and switch closing of the switch to respectively break and make a conduction path between the first output terminal and the positive supply terminal. The method also includes providing a impedance circuit coupled between a ground terminal of the power supply that supplies the ground voltage level and a second output terminal of the management circuit, whereby the first output terminal and the second output terminal representing respectively a power conductor and a ground conductor configured to provide the first voltage level and the ground voltage level respectively to an electronic device when the electronic device is coupled to the management circuit. The method additionally includes monitoring voltages obtained at at least one of the first analog sense node and the second analog sense node using the processor, wherein the voltages at the first sense node and the second sense nodes are derived from one of voltage and current obtained from the first output terminal and the second output terminal, the processor controlling the switch opening and the switch opening based at least on the voltages obtained at the at the at least one of the first analog sense node and the second analog sense node and previous state information pertaining to a present operating state of the management circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
[0010] FIG. 1 shows a schematic diagram of a power supply and a power management circuit, in accordance with an embodiment of the present invention.
[0011] FIG. 2 shows a flow chart describing the steps/actions taken in the disconnected state, in accordance with an embodiment of the present invention.
[0012] FIG. 3 shows a flow chart describing the steps/actions taken in transitioning from the disconnected state to the connected state, in accordance with an embodiment of the present invention.
[0013] FIG. 4 shows a flow chart describing the steps/actions taken while performing “on” status checks, in accordance with an embodiment of the present invention.
[0014] FIG. 5 shows a flow chart describing the steps/actions taken to shut down the power source, in accordance with an embodiment of the present invention.
[0015] FIG. 6 shows a flow chart describing the steps/actions taken in testing for the low-power scenario or the decoupling scenario, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0016] The present invention will now be described in detail with reference to a few embodiments thereof as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without some or all of these specific details. In other instances, well known process steps and/or structures have not been described in detail in order to not unnecessarily obscure the present invention.
[0017] Various embodiments are described hereinbelow, including methods and techniques. It should be kept in mind that the invention might also cover articles of manufacture that includes a computer readable medium on which computer-readable instructions for carrying out embodiments of the inventive technique are stored. The computer readable medium may include, for example, semiconductor, magnetic, opto-magnetic, optical, or other forms of computer readable medium for storing computer readable code. Further, the invention may also cover apparatuses for practicing embodiments of the invention. Such apparatus may include circuits, dedicated and/or programmable, to carry out tasks pertaining to embodiments of the invention. Examples of such apparatus include a general-purpose computer and/or a dedicated computing device when appropriately programmed and may include a combination of a computer/computing device and dedicated/programmable circuits adapted for the various tasks pertaining to embodiments of the invention.
[0018] FIG. 1 is a schematic representation of a power protection circuit (PPC) 100 in accordance with an embodiment of the present invention. FIG. 1 shows a power supply (PS) 102 , representing a direct current power source having a negative terminal 102 a and a positive terminal 102 b , and a shut-down terminal 102 c . Power supply terminals 102 b and 102 a supply power and ground respectively to operate PPC 100 and an electronic device 150 if the electronic device is coupled to PPC 100 . Shut-down terminal 102 c is configured to receive a shut-down signal from a processor 104 of PPC 100 to shut down power supply 102 in case there is a fault condition, for example.
[0019] Power supply 102 may represent, for example, a power adapter that transforms household voltages (e.g., 110V or 220V) to voltage and current levels suitable for operating PPC 100 and electronic device 150 in accordance with user specification. In the example of FIG. 1 , electronic device 150 represents a laptop computer although electronic device 150 may represent any power consuming electronic device, whether or not equipped with a battery.
[0020] Positive supply terminal 102 b is shown coupled to a processor-controlled switch 126 , which opens and closes responsive to a control signal from processor 104 to respectively break and make electrical contact with a node 140 . Node 140 is coupled to a pin (not shown) in a connector 108 to transmit power to a node 160 of electronic device 150 when power supply 102 is turned on, switch 126 is closed, and electronic device 150 is coupled to PPC 100 . A node 142 at the bottom of FIG. 1 provides a grounding path for circuitry within electronic device 150 when connector 108 of PPC 100 and connector 110 of electronic device 150 are coupled together. Nodes 140 and 142 represent, for example, the wired conductors that are employed to carry power and ground from the circuitry bulk of the power adapter to the plug that is mated with the laptop computer. The components of PPC 100 may be integrated within the power adapter housing that also houses power supply 102 , in an embodiment.
[0021] In parallel with switch 126 is an impedance circuit 114 , represented in the example of FIG. 1 by a resistor R 1 . As will be discussed later herein, impedance circuit 114 along with impedance circuit 116 (represented by a resistor R 2 in the example of FIG. 1 ), impedance circuit 118 (represented by a resistor R 3 in the example of FIG. 1 ), and impedance circuit 120 (represented by a resistor R 4 in the example of FIG. 1 ) operate cooperatively with power supply 102 , switch 126 , and a differential amplifier 106 to provide sensing voltage levels to analog input nodes 144 and 146 of processor 104 . These voltage levels enable processor 104 to ascertain the operating conditions of power supply 102 and electronic device 150 . These operating conditions in turn enable processor 104 to appropriately operate switch 126 and/or power supply 102 to deliver or cut off power to node 140 .
[0022] The operation of PPC 100 may be better understood with reference to a few simple example scenarios below. For even more detailed information, discussions of various example scenarios are also discussed in connection with the flowcharts provided with other figures herein.
[0023] The first scenario represents the default situation wherein connector 108 is unconnected, i.e., not coupled to electronic device 150 or any other device. In this case, PPC 100 is said to be in the “unconnected” state, and it is desirable to turn off power to pin 140 to prevent an accidental shorting of the pins of connector 108 from creating sparks and/or damage PPC 100 and/or damage power supply 102 .
[0024] In the default scenario (which also represents a typical starting condition for PPC 100 ), switch 126 is open, thereby effectively interrupting the low-impedance path from positive supply terminal 102 b to node 140 . Since connector 108 is also disconnected from connector 110 of electronic device 150 , no current flows through resistor R 4 , thereby resulting in no voltage difference across resistor R 4 . Differential amplifier 106 (which may represent a stand-alone component or may be integrated with other components such as within processor 104 ) senses the current flowing through resistor R 4 (as reflected by the potential difference across R 4 ) and provides an analog input to processor 104 via sense node 146 . In this case, the analog input at sense node 146 will be essentially zero to reflect the fact that no current flows through resistor R 4 .
[0025] The voltage at sense node 144 is determined by the voltage dividing circuit comprising resistors R 1 , R 2 , and R 3 and reflects a value characteristic of the unplugged state. As long as the voltage at sense node 144 stays within the value range characteristic of the unplugged state (referred to herein as the “unplugged voltage range”), processor 104 keeps switch 126 open.
[0026] The second scenario relates to the situation wherein connector 108 of PPC 100 was previously unconnected but is now connected to connector 110 of electronic device 150 . Further, assume that both PPC 100 and electronic device 150 operate normally (i.e., there are no fault conditions in either PPC 100 or electronic device 150 ). In this case, it is desirable to deliver power from power supply 102 to electronic device 150 after it is ascertained that the coupling between connector 108 and electronic device 150 is satisfactory.
[0027] Starting from the default unplugged state discussed above, the coupling of connector 108 to electronic device 150 changes the impedance seen by nodes 140 and 142 . Even though switch 126 remains open at this point in time, the voltage value at sense node 144 changes due to the fact that an impedance load characteristic of electronic device 150 has now been placed in parallel with resistors R 2 -R 3 . The voltage value at sense node 144 will be in the range (referred to herein as the “good connection voltage range”) that reflects the fact that an impedance load characteristic of electronic device has been coupled to nodes 140 and 142 .
[0028] This voltage value in the “good connection voltage range” is detected by processor 104 (which reads the voltage value at sense node 144 ) and results in the processor recognizing that PPC 100 is now coupled with electronic device 150 . This recognition causes processor 104 to close switch 126 to cause power to be delivered to node 140 from power supply terminal 102 b . For robustness, processor 104 may require that the voltage at sense node 144 stays within the “good connection voltage range” for a given amount of time before switch 126 is closed. This time delay eliminates the possibility that transient voltages at sense node 144 may inadvertently cause processor 104 to close switch 126 . Note that if the voltage at sense node 144 is outside of this characteristic range, the processor would not recognize that PPC 100 is now coupled with electronic device 150 and would not cause switch 126 to be closed.
[0029] PPC 100 is now in the connected state, and the voltage at sense node 146 and/or sense node 144 are monitored for other scenarios. Note that in this connected state, the current through R 4 will be higher than in the unplugged state, causing differential amplifier 106 to sense the larger voltage difference across R 4 . As will be discussed later herein, the sensed voltage difference across R 4 is employed to ascertain the transition to other operating states from the connected state.
[0030] The next example relates to the situation wherein the voltage difference across resistor R 4 drops. This voltage difference across R 4 may drop due to diminished current through resistor R 4 , which in turn may be due to, for example, either the “low power” scenario or the “decoupling” scenario.
[0031] In the “low-power” scenario, the user may have turned off the laptop computer while leaving the power adapter plugged in. In this case, the user may for example wish to continue to trickle charge the battery of the laptop as needed to prevent a “brown-out” condition. As another example, certain electronic device continues to have a portion of their circuitry operating in the low-power mode (e.g., sleep or hibernate or watch-dog circuitry). In these cases, the appropriate action is to continue supplying power to node 140 even though processor 104 may have sensed at sense node 146 that the current through R 4 has dropped.
[0032] Alternatively, in the “decoupling” scenario, the user unplugs connector 108 from connector 110 . In this case, it is desirable to interrupt power delivery to node 140 from positive supply terminal 102 b by opening switch 126 .
[0033] In an embodiment, both the low-power scenario and the decoupling scenario are first detected when the current through resistor R 4 drops below a certain “connection” threshold. In other words, as soon as the voltage at sense node 146 drops below the “connection” threshold (typically some small voltage level above zero), processor 104 deems that the connected state is terminated and PPC 100 may be transitioning to either the low-power scenario or the decoupling scenario.
[0034] The low-power scenario is ascertained and handled as follows. Upon detecting that the current through resistor R 4 has dropped below the “connection” threshold (as evidenced by the voltage across R 4 , which is sensed by processor 104 via differential amplifier 106 ), processor 104 commands switch 126 to open to interrupt the flow of current from positive supply terminal 102 b into node 140 . The opening of switch 126 causes the voltage at node 140 to drop from the high voltage level that existed when switch 126 was closed. The decay of the voltage level at node 140 also causes the voltage level at sense node 144 to decay. The decay at sense node is then monitored by processor 144 . In an embodiment, the level or rate of decay or pattern of decay may be monitored. Generally speaking, processor 144 has internal memory or access to memory to stores in advance information such as expected voltage levels of various states/scenarios, expected decay rate, expected plot of voltage and/or current versus time, voltage thresholds, timer duration, etc.
[0035] If the voltage at sense node 144 is characteristic of a PPC that transitions from a connected state to a low-power state (e.g., in the case where the user turns off the laptop computer but leaves the laptop computer connected to PPC 100 , thereby reducing the current draw but leaving the system impedance of electronic device 150 connected across nodes 140 and 142 ), processor 104 turns on switch 126 to allow power delivery to resume to node 140 . This permits, as mentioned earlier, power to be delivered to the laptop computer to, for example, prevent a “brown-out condition” or keep some small watch-dog circuits active. In an embodiment, a small delay may be built-in (via a timer, for example) between the cycles of sensing the drop at sense node 144 and turning on switch 126 so that switch 126 is not needlessly cycled on and off rapidly. For example, a delay may be provided such that the maximum off-and-on switch rate of switch 126 is about 3 times a second during the “low-power” state.
[0036] If, however, the voltage at sense node 144 is characteristic of a PPC that transitions from a connected state to a disconnected state (e.g., in the case where the user unplugs the laptop computer from the PPC 100 , thereby removing the system impedance of electronic device 150 from nodes 140 and 142 ), processor 104 keeps switch 126 off after the voltage at sense node 144 stays above the “connection” threshold after a period of time. This is a desirable result to keep power from being delivered to the pins of an unplugged power adapter.
[0037] Another scenario relates to the case wherein the pins of connector 108 are shorted when switch 126 is off. As expected, this should not cause any damage since no appreciable amount of power is delivered to node 140 when switch 126 is turned off. However, since there is current flowing through the R 1 -R 2 -R 3 loop, as well as through the R 1 -shorted pins-R 4 loop, an analysis is provided for completeness. Resistor R 4 is typically much smaller than resistor R 1 . For example, resistor R 4 may be in the range of milli-ohms such as 10 milli-ohms in an embodiment. As a further example, resistor R 1 may be in the range of kilo-ohms, such as about 150 kilo-ohms in an embodiment. In this case, most of the voltage drop in the R 1 -shorted pins-R 4 loop will be across resistor R 1 when the pins of connector 108 are shorted, causing the voltage level at node 140 to drop to nearly zero.
[0038] This near-zero voltage at node 140 is reflected at sense node 144 due to the voltage divider circuit of loop R 1 -R 2 -R 3 and sensed by processor 104 . Since the low voltage at sense node 144 is lower than the aforementioned “good connection voltage range,” processor 104 does not turn on switch 126 . In fact, even if transient conditions during the shorting process causes the voltage at node 144 to happen to be in the aforementioned “good connection voltage range,” it is highly unlikely that this transient condition would stay stable long enough to satisfy the stable time requirement imposed by the delay clock. If the voltage at sense node 144 does not stay in the aforementioned “good connection voltage range” for the requisite time period imposed by the delay clock, processor 104 does not turn on switch 126 .
[0039] Another scenario relates to the case wherein connector 108 is plugged into an electronic device but a short occurs after switch 126 is closed. In other words, the short is experienced after power is delivered to node 140 (and to any connected electronic device). In this case, it is desirable to immediately turn off switch 126 (and optionally to immediately turn off power supply 102 ) to prevent further damage.
[0040] After connector 108 is plugged into the electronic device and switch 126 is closed, the voltage drop across resistor R 4 is watched by processor 104 via differential amplifier 106 as mentioned. If the current through resistor R 4 exceeds a first “dangerous” threshold level for a certain time period (which high current condition is reflected in the large voltage difference across R 4 and sensed by processor 104 via amplifier 106 and node 146 ), processor 104 opens switch 126 and turns off power supply 102 (by issuing a command via terminal 102 c ).
[0041] In an embodiment, a second, “critical” threshold that is higher than the “dangerous” threshold may be established. If the current through resistor R 4 exceeds the critical threshold level (which critical current condition is reflected in the larger voltage difference across R 4 and sensed by processor 104 via amplifier 106 and node 146 ), processor 104 immediately opens switch 126 and immediately turns off power supply 102 (by issuing a command via terminal 102 c ) substantially without any delay.
[0042] In this manner, a persistent and dangerous high current fault condition will cause switch 126 to be opened and power supply 102 to be turned off after some time. A critical high current fault condition will cause switch 126 to be immediately opened and power supply 102 to be immediately turned off.
[0043] Alternatively or additionally, the voltage at sense node 144 may also be monitored. In an embodiment, if the voltage at sense node 144 stays below a first shut-off voltage threshold for a given period of time, processor 104 opens switch 126 and turns off power supply 102 (by issuing a command via terminal 102 c ). In an embodiment, if the voltage at sense node 144 falls below a second shut-off voltage threshold that is lower than the first shut-off voltage threshold, processor 104 immediately opens switch 126 and immediately turns off power supply 102 (by issuing a command via terminal 102 c ) substantially without any delay.
[0044] FIG. 2 is an illustrative flowchart of a method of monitoring a power circuit in accordance with an embodiment of the present invention. At a first step 202 , the method assumes that the PPC is disconnected from an electronic device. At a next step 204 , switch 126 (see FIG. 1 ) is turned off or opened. As noted above, when switch 126 is opened and PPC 100 is unconnected to the electronic device, no power is delivered to node 140 . However, current still flows through the R 1 -R 2 -R 3 loop, allowing processor 104 to monitor the voltage level at sense node 144 (step 206 ). In some embodiments, the frequency of monitoring occurs at approximately 1,000 hertz although other suitable monitoring frequencies are also possible.
[0045] If, as shown in step 208 , the voltage at sense node 144 enters into the range R 1 (e.g., the aforementioned “good connection voltage range”), the method proceeds to step 302 wherein operating parameters/conditions of the PPC are tested to determine the appropriate action(s) to be taken next. On the other hand, if the voltage at sense node 144 stays outside of this range, the PPC remains in the disconnected state, and the method returns from step 208 to step 206 to continue to monitor the voltage at sense node 144 .
[0046] FIG. 3 is an illustrative flowchart of a method of protecting a power circuit when the PPC transitions out of the disconnected state, in accordance with an embodiment of the present invention. Generally speaking, after the voltage at sense node 144 enters the voltage range R 1 (e.g., the aforementioned “good connection voltage range”), the steps of FIG. 3 ascertain whether the voltage at sense node 144 stays stable within the range for a predefined time period (determined by a timer T 1 ) or is a transient condition. If the voltage at sense node 144 stays stable within the voltage range R 1 for a predefined time period (determined by a timer T 1 ), switch 126 is turned on to deliver power to node 140 . On the other hand, if the voltage at sense node 144 does not stay stable within the range R 1 for a predefined time period, transients are deemed to be the cause for the fluctuation of the voltage level at sense node 144 , and the PPC transitions back to the disconnected state of FIG. 2 without turning on switch 126 .
[0047] Thus, at step 302 , the power supply 102 is shown to be on but switch 126 remains off. Step 302 is arrived at from step 208 of FIG. 2 when the voltage at sense node 144 enters the voltage range R 1 (e.g., the aforementioned “good connection voltage range”). In this case, the voltage at sense node 144 is continued to be monitored (step 304 ). If the voltage at sense node 144 stays in the voltage range R 1 , the method checks to see if the stable period requirement has been satisfied (steps 310 , 312 , and 314 ). Thus, in step 310 and 312 , the timer is started if a timer has not been started. After the timer is started (step 312 ) or if the timer has already started (yes branch of step 310 ), the method checks at step 314 to determine whether the timer has expired.
[0048] If the timer has expired while the voltage at sense node 144 stays within the voltage range R 1 (yes branch of step 314 ), the operating state of the PPC is deemed to be the connected state ( 316 ), and switch 126 is then turned on ( 318 ). Thereafter, the method monitors the voltage at one or both of sense nodes 144 and 146 to monitor the operating status. This monitoring will be discussed later herein.
[0049] On the other hand, if the timer has not expired while the voltage at sense node 144 stays within the voltage range R 1 (no branch of step 314 ), the method returns from step 314 to step 304 to continue to monitor the voltage at sense node 144 .
[0050] Note that if the voltage at sense node 144 drops outside of the voltage range R 1 before the timer expires, the timer is stopped and reset (no branch of step 306 and step 308 ), and the method returns to the disconnected state of step 202 of FIG. 2 .
[0051] FIG. 4 is an illustrative flowchart of the “ON” status checks (step 320 ), in accordance with an embodiment of the present invention. Generally speaking, steps 402 , 404 , 406 , 408 , and 410 ascertain whether a dangerous or critical current condition has occurred while the PPC is in the connected state and switch 126 is closed. Steps 414 , 416 , 418 , and 420 check to see whether a low voltage condition seen across resistor R 4 represents a dangerous/critical situation, the “low power” scenario (e.g., the user turns off the laptop computer but leaves the power adapter plugged in) or the “decoupling” scenario (e.g., the user disconnects the laptop computer from the power adapter).
[0052] At step 402 , the current through resistor R 4 is checked (by processor 104 via node 146 and differential amplifier 106 ) to see whether that current exceeds a critical threshold CT 1 . If the current through resistor R 4 exceeds this critical threshold CT 1 , the method proceeds to step 502 of FIG. 5 to immediately turn off all timers (step 502 of FIG. 5 ) and to turn off the power supply 102 (step 504 of FIG. 5 ). Alternatively or additionally, the processor may also open switch 126 . Thereafter, the method returns from step 504 of FIG. 5 to step 202 of FIG. 2 (representing the disconnected state).
[0053] At step 404 (from the no branch of step 402 ), it is ascertained whether the current through resistor R 4 exceeds a lesser but potentially dangerous threshold. If not (no branch step 404 ), the method proceeds to step 412 to begin checking to see whether a low voltage condition exists at sense node 144 . As mentioned, the low voltage condition at sense node 144 may exist due to, for example, a short that occurs when power is being delivered. Note that this check (steps 412 , 414 , 416 , 418 , and 420 ) is shown in series with the high current check of steps 402 - 412 . In practice, these two checks may be made in parallel if desired.
[0054] Returning to step 404 , if on the other hand the current through resistor R 4 exceeds a lesser but potentially dangerous threshold, the method proceeds to one or more of steps 406 , 408 , 410 , and 412 to check whether the dangerous but non-critical current condition persists longer than a predefined time (as measured by timer T 2 ). Thus, in step 406 and 408 , timer T 2 is started if timer T 2 has not been started. After timer T 2 is started (step 408 ) or if timer T 2 has already started (yes branch of step 406 ), the method checks at step 410 to determine whether timer T 2 has expired.
[0055] If timer T 2 has expired while the current through resistor R 4 remains above the dangerous threshold “TIMED CURRENT THRESHOLD,” (yes branch of step 410 ), the method proceeds to step 502 of FIG. 5 to turn off all timers (step 502 of FIG. 5 ) and to turn off the power supply 102 (step 504 of FIG. 5 ). Alternatively or additionally, the processor may also open switch 126 . Thereafter, the method returns from step 504 of FIG. 5 to step 202 of FIG. 2 (representing the disconnected state).
[0056] As mentioned, one or more of steps 412 , 414 , 416 , 418 , and 420 implements the low voltage condition check for the voltage at sense node 144 . The voltage at sense node 144 may become critically low if, for example, there exists a short between terminals 140 and 142 after connector 108 is plugged in and power is being delivered to terminal 140 . In step 412 , the voltage at sense node 144 is checked (by processor 104 ) to see whether that voltage drops below a critical voltage threshold VT 1 . In an embodiment, VT 1 may be, for example, 0.5V. If the voltage at sense node 144 falls below the critical voltage threshold VT 1 , the method proceeds step 502 of FIG. 5 (yes branch of step 412 ) to immediately turn off all timers (step 502 of FIG. 5 ) and to turn off the power supply 102 (step 504 of FIG. 5 ). Alternatively or additionally, the processor may also open switch 126 . Thereafter, the method returns from step 504 of FIG. 5 to step 202 of FIG. 2 (representing the disconnected state).
[0057] At step 414 (from the no branch of step 412 ), it is ascertained whether the voltage at sense node 144 falls below a higher-than-critical but still potentially dangerously low voltage threshold TIMED VOLTAGE THRESHOLD. This situation may happen, for example, if a defect in power supply 102 causes power supply 102 to output a dangerously low voltage.
[0058] If the voltage at sense node 144 falls below the higher-than-critical but still potentially dangerously low voltage threshold TIMED VOLTAGE THRESHOLD, a timer is watched to determine if the voltage at sense node 144 stays below this threshold for longer than a predetermined time period (determined by timer voltage T 3 ). This watch is performed by steps 416 , 418 , and 420 . Thus in step 418 , if timer T 3 has not started (no branch of step 416 ), timer T 3 is started. If timer T 3 has started (yes branch of step 416 ), step 420 checks to see if voltage timer T 3 has expired. If voltage timer T 3 expired while the voltage at sense node 414 remains under the higher-than-critical but still potentially dangerously low voltage threshold TIMED VOLTAGE THRESHOLD, the method proceeds to step 502 of FIG. 5 (yes branch of step 420 ) to turn off all timers (step 502 of FIG. 5 ) and turn off the power supply 102 (step 504 of FIG. 5 ). Alternatively or additionally, the processor may also open switch 126 . Thereafter, the method returns from step 504 of FIG. 5 to step 202 of FIG. 2 (representing the disconnected state).
[0059] Returning to step 414 , if voltage at sense node 144 does not fall below the higher-than-critical but still potentially dangerously low voltage threshold TIMED VOLTAGE THRESHOLD, the PPC is operating normally and the method proceeds to step 602 of FIG. 5 to begin checking whether a low current condition exists across resistor R 4 . As mentioned, this low current condition may be indicative of either a “decoupling” scenario (e.g., the user disconnects the power adapter from the laptop computer) or a “low-power” scenario (e.g., the user turns off the laptop computer but leaving the power adaptor plugged in.
[0060] Thus, in step 602 of FIG. 6 , the current through resistor R 4 is monitored (by processor 104 via differential amplifier 106 and node 146 ) to ascertain whether this current drops below a current threshold CT 2 (e.g., minimum current output by power supply for an operational laptop in an embodiment). If the current through resistor R 4 stays above current threshold CT 2 , the system is deemed to operate normally in which case the method returns to step 320 of FIG. 3 (yes branch of step 602 ) to back to continue “on” status checks.
[0061] On the other hand, if the current through resistor R 4 falls below the current threshold CT 2 (no branch of step 602 ), the method proceeds to ascertain whether the low current condition through resistor R 4 is indicative of a “decoupling” scenario or a “low-power” scenario. In step 604 , a low power timer is started. In step 606 , switch 126 is turned off. In steps 608 - 612 , the method monitors the voltage level at sense node 144 (which steady-state level and/or rate of decay depends on whether the system impedance of the electronic device is still seen by terminals 140 and 142 ).
[0062] If the voltage at sense node 144 stays above a voltage threshold VT 2 for longer than a time period determined by a low power timer, the “decoupling” scenario is deemed to have occurred. This voltage threshold VT 2 for sense node 144 is selected to be the voltage threshold that discriminates between the case where the laptop is still connected to the power adapter but the laptop is turned off and the case where the laptop is disconnected from the power adapter. In the case where sense node 144 stays above a voltage threshold VT 2 for longer than the low power period (no branch of step 610 and yes branch of step 612 ), the method proceeds to step 202 of FIG. 2 to start operating from the disconnected state again.
[0063] Returning to step 610 , if the voltage at sense node is below the voltage threshold VT 2 (yes branch of step 610 ), the method proceeds to step 316 of FIG. 3 to turn switch 126 back on (since switch 126 was turned off in step 606 ). In this case, the processor 104 has determined that the electronic device is turned off but still plugged in (i.e., its characteristic impedance is still seen by terminals 140 and 142 and still affecting the rate of decay at node 140 and sense node 144 after switch 126 is turned off). Turning the switch 126 back on in step 316 of FIG. 3 allows the PPC to begin the “on” status checks again (since switch 126 is closed even if a high operating current is not presently required by the dormant-but-plugged-in electronic device 150 ).
[0064] As can be appreciated from the foregoing, embodiments of the invention permit various operating conditions of the power supply to be accurately monitored and appropriate actions to be rapidly and appropriately taken with respect to different operating scenarios and operating states. Embodiments of the invention rely not only on contemporaneous measurements of electrical parameters to perform its power supply managing tasks (as would be the case with an analog controller) but also on present state information (i.e., the state the PPC is currently in before switching to the next state) and the voltage level/pattern information received at sense nodes 144 and 146 to more accurately and rapidly perform its tasks.
[0065] Advantageously, embodiments of the invention employ the power and ground conductors for its monitoring tasks. In this sense, it may be said that the voltage information that exist on analog sense node 144 and analog sense node 146 is obtained through (i.e., derivative of or deriving from) voltage and/or current at/on/through terminals 140 and 144 (which are the power conductor and the ground conductor that supply power voltage level and ground voltage level to the electronic device), thereby eliminating the need for a separate sense wire/conductor between the circuitry of the PPC and the circuitry of the electronic device and/or the circuitry of the power supply
[0066] While this invention has been described in terms of several embodiments, there are alterations, permutations, and equivalents, which fall within the scope of this invention. It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present invention. For example, impedance circuit values and timer values as described herein are highly dependent on the power source specification and the specification of the electronic device, as well as design choices. The impedance circuits may be implemented by resistors or any other suitable impedance arrangements. The power supply may represent a power supply that transforms one voltage level to another or may simply representing a non-transforming (i.e., not translating from one voltage level to another voltage level) power supply. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention. | Circuitry and techniques for managing a power supply are disclosed. A processor-controlled switch is employed to control the delivery of power to conductors that provide power to an external electronic device wherein the processor controls the switch opening and the switch opening based not only on contemporaneous parameter measurements but also on state information known to the processor. The management circuit can control the power supply without requiring the use of an additional sense wire between the management circuit and the external electronic device. | 7 |
RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. application Ser. No. 10/126,676 filed on Apr. 22, 2002.
FIELD OF THE INVENTION
[0002] The following invention relates to a binding assembly for binding sheets. The binding assembly incorporates an alignment mechanism.
BACKGROUND OF THE INVENTION
[0003] It is well known to print individual sheets of a volume to be bound, place all of the printed sheets into a stack, crop one or more edges of the stack and to bind the sheets together by applying a binding adhesive to an edge of the stack of sheets. This is a time consuming and labour-intensive process.
[0004] It would be more efficient to provide pre-cut, uniformly sized sheets, print one or both surfaces of each sheet and provide a strip of binding adhesive to one or both surfaces of each sheet adjacent the edge to be bound. Then the printed and pre-glued sheets can be placed accurately in a stack, and the sheets adjacent the spine pressed so that the adhesive binds the sheet edges together.
[0005] It would also be desirable to provide an apparatus and method for applying a strip or strips of binding adhesive to a sheet as the sheet passes through a printer.
SUMMARY OF THE INVENTION
[0006] According to a first aspect of the invention, there is provided a binding assembly for generating bound documents, the binding assembly comprising:
[0007] a support structure that defines a floor onto which sheets to be bound are conveyed and a wall that extends from the floor to define a stop for the sheets that are fed onto the floor, each sheet having a strip of adhesive proximate a leading edge of the sheet;
[0008] a vibration imparting mechanism that is operatively engaged with the support structure and operable to vibrate the support structure; and
[0009] a binding mechanism that is arranged on the support structure and is displaceable with respect to the support structure to act on each sheet fed into the support structure such that the sheets are adhered together with the strips of adhesive.
[0010] The binding assembly may include a frame, the support structure being a tray that is suspended from the frame.
[0011] A damping mechanism may be interposed between the frame and the tray to damp the vibration of the support structure.
[0012] The vibration imparting mechanism may be a vibrator that is engaged with a corner of the tray. The vibrator may be a subsonic vibrator or an unbalanced electric motor.
[0013] The binding mechanism may include a binding press that is positioned above the support structure to be aligned with leading edges of stacked sheets. The binding press may be operable to urge said leading edges against each other so that the adhesive serves to bind the sheets together.
[0014] According to a second aspect of the invention, there is provided a method of generating bound documents, the method comprising the steps of:
[0015] conveying sheets of a print medium through a printing station;
[0016] carrying out a printing process on the sheets in the printing station;
[0017] conveying the sheets through an adhesive application station;
[0018] applying adhesive to each sheet proximate an edge of each sheet in the adhesive application station;
[0019] stacking a predetermined number of the sheets at a stacking station, so that respective strips of adhesive are aligned with each other; and
[0020] performing a binding operation on said predetermined number of sheets so that said predetermined number of sheets are bound together to define a document.
[0021] The step of carrying out a printing process on the sheets may comprise ejecting ink from an ink jet printhead on to the sheets.
[0022] The step of applying adhesive to the sheets may comprise the step of applying at least one adhesive strip to an edge of each sheet to be bound, while the sheet moves through the adhesive application station.
[0023] The adhesive strip may be applied to each sheet by ejecting the adhesive from an adhesive applicator positioned at the adhesive application station without the adhesive applicator making contact with the sheet.
[0024] The adhesive may be sprayed on to each sheet. In particular, the adhesive may be sprayed on to both sides of the sheet to apply the adhesive strip to each side of the sheet.
[0025] Instead of spraying the adhesive, the method may include the step of bringing at least one adhesive applicator into contact with the sheet while the sheet passes through the adhesive application station.
[0026] In one embodiment, the method may include the step of bringing a pair of opposed adhesive applicators into contact with the sheet so that the adhesive strip is applied to each side of the sheet. In particular, the method may include the step of bringing a pair of opposed adhesive applicator rollers into contact with the sheet so that the adhesive strip is applied to each side of the sheet.
[0027] The, or each, adhesive strip may be applied to a trailing edge of each sheet. Instead, the, or each, adhesive strip may be applied to a leading edge of each sheet.
[0028] The step of stacking the sheets may include feeding the sheets into a stacking tray of the stacking station, so that the sheets bear against a part of the stacking station, with the adhesive strips of the sheets aligned with respect to each other.
[0029] The step of performing the binding operation may include the step of applying pressure to the stacked sheets at a position aligned with the adhesive strips of the stacked sheets so that the adhesive strips serve to bind the stacked sheets together.
[0030] The invention is now described, by way of example, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] [0031]FIG. 1 is a schematic illustration showing an adhesive being applied to a sheet of print medium, in accordance with a method of the invention.
[0032] [0032]FIG. 2 is a schematic illustration of a sheet with an adhesive strip positioned adjacent one edge of the sheet, as a result of the working of a method in accordance with the invention.
[0033] [0033]FIG. 3 is a table schematically illustrating the principles of five alternative embodiments of the method of the invention.
[0034] [0034]FIG. 4 is a schematic view of a number of sheets with all but the top sheet having a strip of adhesive applied to an upper surface adjacent to an edge to be bound.
[0035] [0035]FIG. 5 is a schematic view of a stack of sheets with all but the bottom sheet having a strip of adhesive applied to a lower surface thereof adjacent to an edge to be bound.
[0036] [0036]FIG. 6 is a schematic view of a stack of sheets with a first part of a two-part adhesive applied to the upper surface of all but the top sheet and a second part of a two-part adhesive applied to the bottom surface of all but the bottom sheet, in accordance with a method of the invention.
[0037] [0037]FIG. 7 is a schematic perspective view of a support tray situated immediately down-line of the adhesive applicator, and used in a method of the invention.
[0038] [0038]FIG. 8 is a schematic cross-sectional view of the support tray of FIG. 7 showing a first sheet having a strip of adhesive adjacent its edge at an upper surface in an initial path of travel towards the support tray.
[0039] [0039]FIG. 9 is a schematic cross-sectional view of the support tray and sheet of FIG. 8, with the sheet in an intermediate path of travel towards the support tray.
[0040] [0040]FIG. 10 is a schematic cross-sectional view of the support tray and sheet of FIGS. 8 and 9, with the sheet at rest on the tray.
[0041] [0041]FIGS. 11, 12 and 13 are schematic cross-sectional views of the support tray showing a second sheet in a path of travel towards the first sheet.
[0042] [0042]FIG. 14 is a schematic cross-sectional view of the support tray having a number of sheets resting on the support tray, with all but the top sheet having an upwardly facing strip of adhesive adjacent an edge thereof.
[0043] [0043]FIG. 15 is a schematic cross-sectional view of the support tray with a binding press in a path of travel towards an edge of the stacked sheets.
[0044] [0044]FIG. 16 is a schematic cross-sectional view of the support tray with sheets bound by application of the binding press.
[0045] [0045]FIG. 17 is a cross-sectional view of the support tray having a number of individual documents resting on the support tray, prior to the binding press being applied to a top document.
[0046] [0046]FIG. 18 is a schematic cross-sectional view of the support tray and documents of FIG. 17, with all documents having been pressed, one upon another.
[0047] [0047]FIG. 19 is a schematic perspective illustration of a number of documents bound in accordance with the method of the invention.
[0048] [0048]FIG. 20 is schematic view of a support tray incorporating a different binding press to that shown in the preceding drawings, to be used in accordance with the method of the invention.
[0049] [0049]FIGS. 21 and 22 are schematic perspective views of a portion of the binding press of FIG. 20.
[0050] [0050]FIG. 23 is a schematic view of a support tray having an alternative press at a trailing edge of a stack of sheets to be bound.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0051] In FIG. 1, reference numeral 10 generally indicates a process, in accordance with the invention, by which adhesive is applied to a sheet 11 as the sheet 11 passes through a printer incorporating an adhesive applicator.
[0052] A driving station D drives the sheet 11 in the direction of an arrow 32 . The driving station D comprises a pair of opposed pinch rollers 12 . The sheet 11 is driven through a printing station P and then an adhesive application station A. Alternatively, the adhesive application station A precedes the printing station P. However, it is preferred that the adhesive application station A follow the printing station P so that adhesive on the sheet 11 does not clog a print head or print heads of the printing station P.
[0053] For single sided sheet printing, the printing station P comprises a single print head 13 . The print head 13 is a pagewidth drop-on-demand ink jet print head. Alternatively, the print head 13 is that of a laser printer or other printing device. If the sheet 11 is to be printed on both sides, a pair of opposed print heads 13 are provided.
[0054] It will be appreciated that in an embodiment where the print heads 13 are ink jet print heads, wet ink 15 on the sheet 11 could pass through the adhesive application station A. This could result in smudging and distortion of the print on the sheet 11 .
[0055] Thus, the printer incorporates an air cushion application means that is configured to be positioned on either side of the sheet 11 as it passes through the printing station P. The print head 13 defines an airflow path or gap 14 through which air can pass to generate the air cushion. It will be appreciated that the air serves to dry the ink.
[0056] The adhesive application station A can comprise an adhesive applicator 16 at one or both sides of the sheet 11 , depending upon which side or sides of the sheet to which adhesive is to be applied.
[0057] As shown in FIG. 2, the sheet 11 having matter printed thereon by printing station P also includes a strip 17 of adhesive applied at the adhesive application station A.
[0058] The strip 17 is positioned adjacent to a leading edge 27 of sheet 11 . The application of strip 17 adjacent to the leading edge 27 is suitable for those situations where the adhesive applicator does not touch the sheet 11 , or touches the sheet 11 at a velocity accurately matching that of the sheet 11 as it passes the adhesive application station A. Alternatively, the strip 17 is applied adjacent to a trailing edge 28 of the sheet 11 . This is more suited to adhesive applicators that make physical contact, such as brushing, with the sheet 11 as it passes the adhesive application station A.
[0059] A margin 29 between the strip 17 and edge 27 or 28 of sheet 11 is 1 to 2.5 mm wide.
[0060] Various methods of applying adhesive to the sheet 11 are envisaged, some of which are schematically depicted in FIG. 3.
[0061] Method 1 in FIG. 3 is a non-contact method of applying adhesive to the moving sheet 11 . In this method, a stationary adhesive applicator 16 sprays adhesive on to one side of the sheet 11 as it passes the adhesive applicator 16 . The adhesive applicator 16 is formed integrally with the print head 13 . Instead, the adhesive applicator is located upstream or downstream with respect to the print head 13 .
[0062] Method 2 also applies adhesive to one side of the moving sheet 11 . However, in this method, an adhesive applicator 16 . 1 touches the sheet 11 while applying the adhesive. The adhesive applicator 16 . 1 is pivotally mounted about a fixed pivot point and is pivoted so that a tangential speed of the applicator matches a speed at which the sheet 11 passes through the adhesive application station A. A reaction roller 30 bears against an underside of the sheet 11 as the adhesive applicator 16 . 1 applies adhesive to the sheet 11 .
[0063] Method 3 applies adhesive to both sides of the sheet 11 as it passes through the adhesive application station A. A pair of opposed, pivotally mounted adhesive applicators 16 . 2 are pivoted so that a tangential speed of the applicators matches a speed at which the sheet 11 passes through the adhesive application station A. Thus, the applicators 16 . 2 both touch the sheet 11 simultaneously and mutually counteract each other's force component normal to the sheet 11 .
[0064] Method 4 employs a pair of adhesive applicator rollers 16 . 3 spaced from either side of the sheet 11 until activated to apply adhesive. At that point, the rollers 16 . 3 move toward and touch the sheet 11 , leaving the strip of adhesive 17 at either side of the sheet 11 . The rollers 16 . 3 mutually counteract each other's force component normal to sheet 11 .
[0065] Method 5 employs a pair of adhesive spray applicators 16 . 4 positioned on each side of the sheet 11 . The applicators 16 . 4 do not touch the sheet 11 . Each applicator 16 . 4 applies one part of a two-part adhesive to a respective side of the sheet 11 so as to apply strips 17 a and 17 b . Like Method 1 , Method 5 employs an adhesive applicator formed integrally with the print head 13 . A channel for the flow of one part of a two-part adhesive is provided in each print head 13 .
[0066] The use of a two-part adhesive is beneficial in situations where there might be some delay in the printing/binding operation. The reason for this is that the two part adhesive requires mixing in order for setting to occur. Thus, if there were a computer software or hardware malfunction partway through a printing/binding operation, the use of a two-part adhesive could provide sufficient time within which to rectify the problem and complete the binding process.
[0067] [0067]FIG. 4 illustrates a stack of sheets 11 with all but the top sheet provided with an adhesive strip 17 at an upper surface adjacent one edge to be bound.
[0068] An alternative is depicted in FIG. 5 wherein all but the bottom sheet has an adhesive strip 17 applied to its bottom surface adjacent an edge to be bound.
[0069] In FIG. 6, a stack of sheets is shown with a part 17 A of a two-part adhesive applied to the upper surface of all but the top sheet 11 and a second part 17 B of the two-part adhesive applied to the bottom surface of all but the bottom sheet 11 .
[0070] When the stacks of sheets of FIGS. 4 and 5 are pressed together, adhesion of the sheets occurs as a result of mixing of the parts 17 A and 17 B.
[0071] When the sheets 11 of FIG. 6 are pressed together, the respective parts of the two-part adhesive in strips 17 A and 17 B combine so as to react and set.
[0072] In an embodiment where the print head 13 is an ink jet print head, and non-contact adhesive application Methods 1 and 5 are employed, the adhesive strip 17 is applied to sheet 11 before ink on the sheet 11 passing through the adhesive application station 10 has dried. Air passing through the air gap 14 accelerates the drying process. Adhesive is applied to the sheet 11 as it passes out of the print head 13 . The air passing through the gap 14 facilitates a relatively high velocity of the sheet 11 , even though the adhesive strip 17 is applied to the sheet 11 .
[0073] When the strip 17 is applied alongside the leading edge 27 of the sheet 11 , any alteration to the velocity of sheet 11 would adversely affect print quality. Hence, application of the adhesive strip 17 alongside the leading edge 27 is carried out using non-contact adhesive application methods or methods where the velocity of the adhesive applicator touching the sheet 11 is substantially the same as that of the sheet 11 .
[0074] When the adhesive strip 17 is applied alongside the trailing edge 28 of the sheet 11 , the same situation is also desirable. For example, if the speed of the adhesive applicator of Methods 2 to 4 was faster than that at which the sheet 11 was passing the print head 13 , the sheet 11 could buckle.
[0075] A particular embodiment of the present invention incorporates the use of a two-part adhesive. Further, in this embodiment, the adhesive applicators are positioned within the print heads 13 themselves. Thus, the print head 13 defines at least one passage for the flow of adhesive through the print head 13 . The advantage of this embodiment is that it would provide space and cost saving benefits.
[0076] The likelihood of adhesive “gumming” and blocking such channels is diminished where a two-part adhesive is used. This is achieved by having only one part of the two-part adhesive passing through any particular channel or channels of the print head 13 .
[0077] Where respective parts of a two-part adhesive are applied to opposed sides of the sheets 11 , those respective parts pass through dedicated channels in the respective print heads 13 on either side of the sheet 11 . This greatly reduces the likelihood of adhesive blockages in the flow channels.
[0078] The adhesive or respective parts of a two-part adhesive can be provided in a chamber of a replaceable ink cartridge providing ink to the print head.
[0079] The print head 13 is positioned proximate the pinch rollers 12 . The reason for this is that the rollers 12 provide a mechanical constraint upon the sheet 11 to enable accurate printing.
[0080] The pinch rollers 12 , print heads 13 and adhesive applicator 16 are illustrated in FIG. 7 alongside a sheet support tray 18 . Thus, the sheet support tray 18 receives sheets 11 once the adhesive strips 17 have been applied to the sheets 11 . The tray 18 is suspended from a frame 21 with respective dampers 22 at each comer of the tray 18 . The dampers 22 are elastomeric dampers or small hydraulic or pneumatic cylinders. The floor of the tray 11 has a lower-most corner 23 beneath which a vibrator 19 is positioned. The vibrator 19 is a subsonic vibrator (i.e. a vibrator having a frequency below 20 hz) or an out-of-balance electric motor.
[0081] A binding press 20 is situated above the tray 18 over aligned leading edges of the sheets 11 , in use. Alternatively, the binding press 20 is positioned over the trailing edge 28 of the sheets 11 .
[0082] In FIG. 8, a first sheet 11 is shown moving towards the tray 18 . The sheet 11 has a strip of adhesive 17 on its upper surface adjacent the leading edge 27 . It will be appreciated that the sheet 11 catches a pocket of air beneath it as it moves into position. This facilitates such movement by reducing friction substantially. The leading edge 28 then strikes a wall 31 of the support tray 18 as shown in FIG. 9. The vibrations of the tray 18 caused by the vibrator 19 results in the sheet 11 coming to rest with the leading edge 27 positioned adjacent the comer 23 of the tray 18 as shown in FIG. 10. Eventually, the leading edges 27 of the sheets 11 bear against the wall 31 of the tray 18 as shown in the drawings.
[0083] In FIG. 11, a second sheet 11 is shown moving towards the tray 18 . The second sheet 11 comes to rest upon the first sheet 11 in a position aligned with the first sheet 11 as depicted in FIG. 13.
[0084] If the sheets 11 have the adhesive strip 17 applied to the upper surface, the final sheet 11 is provided without any adhesive and it comes to rest at the top of the stack as depicted in FIG. 14. If, instead, the majority of sheets 11 had the adhesive strip 17 applied to their bottom surface, the first sheet 11 (i.e. the sheet at the bottom of the stack) would have no adhesive applied to it. This would be suitable for multiple binding compressions.
[0085] As shown in FIG. 15, the binding press 20 is driven downwardly towards the stack of sheets 11 over the aligned adhesive strips 17 . The stack is then compressed into a bound volume 24 as shown in FIG. 16.
[0086] It should be noted that no subsequent edge trimming of the bound volume is required provided standard-sized sheets 11 are used. The reason for this is that the vibrator 19 aligns the sheets 11 into the lower-most comer 23 of the tray 18 as described earlier.
[0087] In FIGS. 17 and 18, multiple volumes 24 are shown stacked one upon another with the upper-most volumes being progressively compressed by repeated applications of the press 20 .
[0088] The binding press 20 is shown schematically in the Figures and could be pneumatically or hydraulically driven, or could be driven by other mechanical means such as rack and pinion, electrical solenoid or otherwise.
[0089] One embodiment of the binding press 20 is depicted in FIGS. 20, 21 and 22 . In this embodiment, the binding press 20 incorporates a plurality of semicircular disks 34 each spaced apart, but fixedly mounted to a common, rotatably driven shaft 36 extending along an axis of rotation 26 . Each disk 34 passes through a respective vertical slot 32 formed in the wall 31 of the tray 18 . In an initial condition, the disks 34 are in the orientation shown in FIG. 21. Upon rotation of the shaft 36 , the disks 34 pivot into a position shown in FIGS. 20 and 22 to press down upon the sheets 11 .
[0090] The tray 18 is provided with a floor of adjustable height so that a top sheet 11 can be positioned proximate the binding press 20 . This reduces noise levels by minimizing a stroke length of the binding press 20 .
[0091] The floor of the tray 18 is driven to move downwardly as each sheet 11 is fed into the tray 18 . This ensures that the top sheet 11 remains at a constant level. This also minimizes the extent of necessary movement of the binding press 20 .
[0092] In the embodiment in which the adhesive strips 17 are applied alongside the trailing edge 28 , the trailing edges 28 are pressed together with a pressing mechanism 38 provided in a position opposite the wall 31 . | A binding assembly for generating bound documents includes a support structure that defines a floor onto which sheets to be bound are conveyed. A wall extends from the floor to define a stop for the sheets that are fed onto the floor. Each sheet has a strip of adhesive proximate a leading edge of the sheet. A vibration imparting mechanism is operatively engaged with the support structure and is operable to vibrate the support structure. A binding mechanism is arranged on the support structure and is displaceable with respect to the support structure to act on each sheet fed into the support structure such that the sheets are adhered together with the strips of adhesive. | 8 |
This invention relates to snubber circuits and, more particularly, to the use of passive non-dissipating components for limiting the voltage peaks on switching transistors.
Prior art snubber circuits for power switching transistors driving inductive loads typically utilize a diode and capacitor to shape the load line of the transistor at turn-off and a series resonant diode-inductor-capacitor circuit which serves the purpose of recharging or resetting the capacitor for the next switching cycle. An example of such a circuit is shown in the TRW Power Semiconductors Handbook, 1980 edition, at page 7-63. The deficiency in the illustrated circuit is that it does not sufficiently control the peak voltage, i.e., the overshoot voltage, on the switching transistor at turn-off. One attempt to improve this failing of the circuit where the inductive load comprises a transformer primary winding involves the addition of a secondary clamp or reset winding connected with a diode to return excess energy in the transformer magnetic core to the input supply. Although this method reduces the overshoot voltage, higher power switching circuits still tend to develop overshoot voltages of sufficient magnitude to damage or destroy the power switching transistor.
BACKGROUND OF THE INVENTION
It is an object of the present invention to provide an improved snubber circuit for a switching transistor which significantly reduces overshoot voltage.
It is a further object of the invention to provide an improved snubber circuit which reduces overshoot voltage with minimum power lost in the snubber components.
In my present invention, a switching transistor is connected to operate at a relatively high-frequency to repetitively connect and disconnect a primary winding of a power transformer across a direct current (DC) power source. A snubber circuit is connected to absorb inductive voltages generated in the transformer winding when the transistor is turned off. The snubber circuit includes a clamp or reset winding on the transformer coupled in series with a diode across the DC power source. A junction intermediate the transistor and primary winding of the transformer is coupled via a capacitor, an inductor and a pair of series connected diodes to the junction intermediate the clamp winding and its series connected diode. An additional capacitor is connected between one terminal of the power source and a junction intermediate the pair of series connected diodes. Another terminal of the power source is connected to each end of the inductor by another pair of diodes. In this arrangement, when the transistor is turned off, the magnetizing current generated in the primary winding of the power transformer is allowed to flow into the capacitor connected to the junction between the transistor and primary winding by means of one of the diodes. The value of the capacitor is selected so as to control the rate at which charge is accumulated thereby shaping the load line of the transistor. At very high power levels when the voltage would become excessive across the transistor, the diode in series with the additional transformer winding breaks over so that further energy is returned to the DC source. Because there is considerable leakage inductance between the primary winding of the transformer and the secondary clamp winding, there may be some overshoot of the voltage before it becomes clamped to the power supply voltage. To prevent this overshoot the additional capacitor is provided so that current conduction through the clamp winding begins prior to the time at which the diode begins to conduct. The inductor and one additional diode allow the two capacitors to be reset at the end of each cycle so that further snubbing can occur at the next turnoff of the transistor.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages of the present invention will become apparent by reference to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is an example of a typical prior art snubber circuit for use in a high power transistor switching circuit.
FIG. 2 is a schematic diagram of a snubber circuit in accordance with the present invention; and
The two graphs designated FIG. 3A and FIG. 3B, represent a set of waveforms comparing the response of the circuit according to FIG. 1 and that according to FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, there is shown a typical prior art snubber circuit for suppressing transient voltages appearing across a switching transistor in a power switching regulator circuit. A transistor 10 is connected in series with a primary winding 12 of a power transformer 14 between a positive DC bus 16 and a negative DC bus 18. A power source 20, illustrated as a battery, provides relatively positive and negative potential between the power busses 16 and 18. The transformer 14 includes a secondary winding 22 which develops an output potential for a load circuit. As shown, the load circuit may include a rectifying diode 24 and a filter capacitor 26 for developing a DC voltage at output terminals 28 and 30. A diode 32, an inductor 34 and a second diode 36 are serially connected between the DC bus 18 and DC bus 16 with the diodes being poled so as to conduct current from the negative bus 18 to the positive bus 16. The junction intermediate the diode 32 and inductor 34 is connected via a capacitor 38 to a junction intermediate the transistor 10 and primary winding 12. A secondary reset or clamp winding 40 wound on transformer 14 is serially connected with a diode 42 between the bus 18 and bus 16 with diode 42 being poled also to conduct current from bus 18 to bus 16. It should be noted that, as indicated by the dot convention, the end of the reset winding 40 adjacent bus 18 is at a positive potential when the end of the primary winding 12 disposed from the bus 18 is at a positive potential.
In the operation of the prior art circuit of FIG. 1, a gating pulse applied to a base terminal of transistor 10 gates transistor 10 into conduction and allows the DC source voltage developed between the busses 16 and 18 to be applied across the primary winding 12 of the power transformer 14. This voltage forces a current to flow through the primary winding 12 thereby delivering power to the transformer and any secondary windings connected thereto. The current through transformer winding 12 creates a leakage flux which, as is well known, will attempt to create a reverse voltage across the transformer winding when the transistor 10 is gated off. At the time that transistor 10 is gated off, the current flowing through the primary winding 12 will continue to flow through the path created by the diode 32 and capacitor 38 charging the capacitor 38 at a rate determined by the magnitude of the current through the primary winding 12 and the size of the capacitor 38. By proper selection of the value of capacitor 38, the turnoff load line can be shaped as desired. While transistor 10 is conducting, the current flowing through primary winding 12 of transformer 14 induces a voltage in reset winding 40 in a direction to reverse bias diode 42 so that no current flows through the diode 42 current path during the on-time of transistor 10.
At very high power levels, the energy transferred into capacitor 38 could result in a voltage rise on capacitor 38 to a value sufficiently high to cause damage to transistor 10. Because the winding 12 acts as a power source while capacitor 38 is charging, the voltage across winding 12 is reversed and consequently the voltage across winding 40 is also reversed. The reversal of voltage across winding 40 is in a direction to forward bias the diode 42; however, no current can flow through the diode 42 and back into the source 20 until such time as the voltage across winding 40 exceeds the source voltage. However, once the voltage across winding 40 exceeds the voltage of source 20, diode 42 becomes forward biased and current flows from winding 40 to source 20. The net effect is to limit or clamp the transient voltage in the circuit to prevent damage to transistor 10.
Due to the lack of perfect coupling between the primary winding 12 and the reset winding 40, there is a time delay associated with the transfer of energy from the winding 12 to the winding 40. At high power levels this transfer time, which is caused by unavoidable leakage reactance between the transformer windings, can be sufficiently large to permit the voltage induced in winding 12 to rise to a relatively high magnitude. This overshoot voltage appears across the transistor 10 and may cause device failure or degradation or require at least a more expensive, higher voltage component. The inductor 34 and diode 36 function to limit the nominal voltage applied to the transistor 10 by starting to conduct once the voltage on capacitor 38 exceeds the combined voltage of the source 20 and the winding 12.
However, the inductor 34 and diode 36 alone can not prevent the shorter duration transient overshoot voltage from rising to levels sufficiently high to damage transistor 10. It will therefore be appreciated that while the prior art snubber circuits have limited the sustained voltage which may appear across a switching element, these circuits have not prevented large overshoot voltages appearing, which overshoot voltages are caused by inductive reactance in the circuit.
Referring now to FIG. 2, in which like numbers refer to like components, there is shown a preferred embodiment of the present snubber circuit which avoids undesirable overshoot voltages during transistor turnoff. As in FIG. 1, the capacitor-diode circuit, i.e. diode 32 and capacitor 38, is connected across primary winding 12. However, in this improved snubber circuit the diode 36, which in the prior art had its cathode connected directly to the positive bus 16, is now connected to the bus 16 through a capacitor 44. The cathode of diode 36 is also connected through a diode 46 to the junction intermediate diode 42 and reset winding 40. An additional diode 48 is connected between the negative bus 18 and the anode of diode 36.
In the operation of this improved snubber circuit, assuming initially that the capacitor 44 is uncharged, gating off of transistor 10 effects a reversal of voltage across primary winding 12 and also a reversal of voltage across winding 40. The voltage reversal across winding 40 creates a negative voltage at the dotted terminal which forward biases diode 46 so that a current path is formed through the capacitor-diode circuit and the clamp winding, i.e. capacitor 44, diode 46 and winding 40. Since capacitor 44 acts as a load to winding 40, the transfer of energy, i.e., current, from winding 12 to winding 40 begins immediately. By proper selection of capacitor 44 and capacitor 38 it is practical to have essentially all the current transferred into winding 40 before the voltage developed on capacitor 38 reaches the clamping level where diode 42 begins to conduct. Thus, as soon as the voltage on capacitor 38 reaches the clamping level, the current transfers from the path through capacitor 44 to the path through diode 42 and back into the source 20 without any inductive delay, thus avoiding any voltage overshoot.
Referring briefly to FIG. 3A there is shown a wave form typically occurring in the circuit of FIG. 1. The voltage level indicated at E represents the clamping voltage, i.e., that voltage at which the diode 42 begins to conduct and limit the voltage on capacitor 38. When the off-time of transistor 10 is sufficiently long, the voltage on capacitor 38 slowly decays down to the voltage potential of the source 20 indicated at V. At initial turnoff of the transistor 10, the rising voltage on capacitor 20 overshoots the clamping voltage E as shown in FIG. 3A. As shown in FIG. 3B the improved snubber circuit of the present invention eliminates the overshoot voltage and also improves the load line shaping by slowing the rise time of the voltage on the primary winding 12.
Referring again to FIG. 2, after the turnoff cycle is complete, i.e., after current in primary winding 12 has been reduced to zero and both capacitor 38 and capacitor 44 are charged to a pedetermined voltage, it is necessary to reset the two capacitors 38 and 44 in preparation for the next cycle of operation. In the preferred embodiment a discharge path is formed from negative bus 18 through primary winding 12, capacitor 38, inductor 34, diode 36, capacitor 44 to the positive bus 16. This particular reset current path is desirable since current flow is in a direction through the primary winding 12 to drive the magnetic core of the transformer 14 into a negative flux region thus allowing the magnetic core material to be more effectively utilized. It should be noted, of course, that the capacitors 38 and 44 do not completely discharge, but rather only discharge to the point where their combined voltages are equal in magnitude to the source voltage impressed between the busses 18 and 16. Diode 36 acts to prevent the power source 20 from reversing the current thus causing the capacitors 38 and 44 to be left charged at some potential slightly below the potential between busses 18 and 16.
In order to further discharge the capacitors 38 and 44, the inventive circuit of FIG. 2 includes a high efficiency resonant tank circuit to further reset the capacitors. The series resonant circuit is formed on the next cycle of operation when the switching transistor 10 is gated into conduction forming a current path through the transistor 10, capacitor 38, inductor 34, diode 36 and capacitor 44 back through transistor 10. Since both transistor 10 and diode 36 have very low voltage drops during conduction, essentially all of the voltage from the capacitors 38 and 44 appears on the inductor 34. This voltage causes a resonant pulse of current to flow through inductor 34. The frequency of the current pulse is determined by the relative values of inductor 34 and capacitors 38 and 44, which values can be chosen to suit circuit requirements. When the capacitors have fully discharged to zero volts, all of their energy has been transferred to the inductor 34. Inductor 34 then returns the energy to the capacitors 38 and 44 by forcing the current to continue to flow after the capacitors have discharged. This current flow acts to reverse the voltage on the capacitors 38 and 44 such that the terminal of capacitor 38 connected to the emitter terminal of transtor 10 now assumes a positive potential. This action completes one-half of a normal resonant cycle. At this point, the capacitors 38 and 44 would now attempt to discharge back through the inductor 34 but such discharge is prevented by the diode 36. Diode 36 has a finite but non-zero reverse recovery time which allows a small reverse current to become established in inductor 34. As diode 36 recovers, diode 48 will conduct to prevent a high transient voltage on inductor 34. Thus, the two capacitors 38 and 44 are now held with a reverse charge of a polarity such that they are more effective on the next turnoff cycle of transistor 10.
The only power dissipation involved in resetting the charge on capacitors 38 and 44 is due to the very low losses in the diode 36, transistor 10 and inductor 34. Typically these losses are in the one to two watt range. This compares very favorably with a resistive type of discharge circuit which would be in the 20 to 30 watt range for a converter using the same type of technique illustrated in FIG. 2.
The embodiment of FIG. 2 is an improved snubber circuit for a bipolar transistor used in a single transistor converter. It will be appreciated that this improved circuit not only prevents overshoot voltages appearing on the transistor but also significantly reduces the losses inherent in a resistive discharge circuit for capacitor components normally associated with a snubber circuit. Although only a single embodiment of this invention has been described in detail, those skilled in the art will appreciate that certain modifications and variations of this embodient may be made without materially departing from the novel and advantageous features of the invention. Accordingly, all such variations and modifications are intended to be included within the scope of this invention as defined by the appended claims. | An improved snubber circuit for a bipolar switching transistor connected to drive an inductive transformer load comprises a first resonant circuit connected to the driven winding of the transformer and a second resonant circuit connected to a clamp winding of the transformer. At turn-off, the two resonant circuits provde an alternate current path for inductive currents to thereby limit the voltage applied to the load transistor. The circuit are interconnected to minimize component count in a manner which permits resetting the capacitive components to improve snubbing capability. | 7 |
CROSS REFERENCED PATENTS
This application is a continuation in part of U.S. app. Ser. No. 09/415,947 filed Oct. 8, 1999, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to building exteriors, and interior wall and ceiling covering using curtain wall systems; said systems having box top shaped composite panels hung on the exterior building sheathing or other framework.
2. Background of the Invention
There are two basic type of systems for the curtain wall aluminum composite material (ACM) market. They are a wet and a dry system. A wet system uses a sealant as its primary seal against moisture. A dry system uses a gasket as its primary seal against moisture.
Most patented curtain wall systems pertain to flat glass panel type curtain wall panels. A brief summary of this flat glass panel support structure art follows below.
U.S. Pat. No. 3,548,558 (1970) to Grossman discloses a mullion system (vertical members between window lights) for a curtain wall exterior. An anchor 101 supports a plate which supports a mullion column having segments 107.
U.S. Pat. No. 3,978,629 (1976) to Echols Sr. discloses a glass panel thermal barrier vertical mullion. Each mullion has an exterior member with a track for maintenance conveyances and has an interior metal member, and has a insulating foam layer therebetween.
U.S. Pat. No. 4,015,390 (1977) to Howorth discloses a glazing structure for a glass panel/curtain wall building.
U.S. Pat. No. 4,121,396 (1978) to Oogami et al. discloses a curtain wall frame structure having channel crossings with four integral legs and backup bars.
U.S. Pat. No. 4,418,506 (1983) to Weber et al. discloses a curtain wall frame structure adding a insulating separator (56) and an insulated bolt to a known frame structure for insulation.
U.S. Pat. No. 4,471,584 (1984) to Dietrich discloses a skylight system with a unique support structure to support a curtain wall flat.
U.S. Pat. No. 4,841,700 (1989) to Matthews discloses a two-piece mullion frame for reducing the face dimension of an aluminum frame.
U.S. Pat. No. 4,996,809 (1991) to Beard discloses a flat panel skylight support frame having built in condensate gutters.
U.S. Pat. No. 5,065,557 (1991) to Laplante et al. discloses a dry gasket seal frame structure for a curtain wall which uses a flat curtain wall panel having inner and outer panel faces, and a spaced apart vertical edge therebetween. A panel can be replaced without having to dismantle any portion of the curtain wall other than the damaged panel.
U.S. Pat. No. 5,199,236 (1993) to Allen discloses a flush appearance glass panel frame structure.
U.S. Pat. No. 5,493,831 (1996) to Jansson discloses a glass panel building support frame presenting a sealed glaze edge between the glass panels.
As Laplante et al. teaches it is advantageous to be able to replace a damaged curtain wall panel using a dry seal, and further advantageous to be able to leave the horizontal and vertical support channels in place for the replacement. The present invention meets these needs in a dry ACM system.
One patented ACM system is U.S. Pat. No. 4,344,267 (1982) to Sukolics which discloses a curtain wall frame structure which allows thermal expansion of the panels to be absorbed by the joints. A vertical channel has a pair of pivotable arms to receive the sides of adjoining panels. In the present invention the exact same ACM may be used. Sukolics requires that a sheathing be installed over the support studs of the building. Then Sukolics' thin and relatively weak, non-structural mullions and horizontal supports can be mounted in a non-sequential (also called non-directional) fashion. This non-sequential erection fashion is preferred over sequential systems. Sequential systems require starting construction at the bottom of a building and progressing left to right, one row at a time, building one row on top of a lower row. Sukolics enables wall construction from the top down which is how rain hits the building during construction. Therefore, using Sukolics' system a builder can erect the frame, complete the roof, then construct the curtain walls from the top down to minimize rain damage to the exposed sheathing of the building.
The present invention provides the same non-sequential method for construction; additionally adding structural mullions and horizontal supports thereby allowing direct fastening to the frame and eliminating the sheathing if desired.
The present invention provides for thermal expansion by means of using floating curtain wall members which expand and contract in their mounting tracks located in the vertical mullions and horizontal supports.
Another prior art reference is a patent pending curtain wall apparatus trademarked RRD200™ by Elward Systems Corporation of Denver, Colo. A combination horizontal support and perimeter extrusion (corner brace) is used, made of aluminum. The top and one side of the curtain wall is firmly bolted to the building. Thus, no “flotation” of the curtain wall exists on an X-Y frame structure as is the case in the present invention. Flotation reduces stresses on the curtain wall panels during thermal and/or stresses on the curtain wall panels setting movement of the building.
Panel installation begins at the bottom with panels inter-leaving at the sides utilizing “male/female” joinery working left to right. Installation continues by stacking the next row on top of the first row and continuing the left to right sequence. Therefore, an individual panel cannot be removed from the center of the wall without removing adjacent panels.
While it is basically a “dry” system because of the use of wiper gaskets, exposed sealant is used in the 4-way intersections due to the male/female differences of the perimeter extrusions.
Rout and return and curtain face support is provided by the perimeter extrusions. The ACM panels are fabricated utilizing known rout and return methodology. The various perimeter extrusions for the curtain wall panels are four different extrusions making the panel “handed”. The present invention uses panels which are symmetrical, facilitating installation.
The system does include a gutter, but it is not continuous and not part of a sub-system, and the gutter only exists on the horizontal member. Weep holes in the horizontal member allow water to flow out and over the curtain wall panels. No integrated X-Y gutter system exists.
The system requires 16-guage (non-standard) studs at precise locations for vertical attachment to the structure, thereby greatly adding to the building cost compared to the present invention. The system does not allow for a “jointless” appearance because it doesn't have a face cap that can be flushed or recessed from the face of the panel. The system does not allow for multiple “joint” colors.
Perimeter extrusions are not the same depth, thus requiring complex shimming; sequential, non-subsystem installation does not allow for integrated three dimensional panels to be incorporated within the system (i.e. signage or column covers, or accent bands that are not flat). The system does not allow for three dimensional joints like a rounded bullnose that would protrude away from the panel.
Another prior art system, shown in FIGS. 1-3, is the Miller-Clapperton MCP System 200-D™ (referred to herein as “the MCP system”). The MCP system employs panels made of aluminum composite material (ACM) 1000 as components of an exterior curtain wall or facade of a building. As shown in the vertical sectional view of FIG. 2, a horizontal attachment support 30 ′ is screwed into sheathing, such as plywood, or through non-structural sheathing, such as gypsum board, into structural building members using structural screws 70 ′. Vertical corner clips 3 ′ and 40 ′ are used to attach the panel 1000 to the horizontal attachment support 30 ′. The clips 3 ′ and 40 ′ attach only to the return leg 22 of panel (i.e., the portion of the panel that is folded 90-degrees after a rout is performed so as to be perpendicular to the face 23 ) and provide no support to the face 23 of the panel. Raised positive return attachment rivets 9 ′ are used to attach the clips.
A continuous inverted support channel 60 ′ is secured by a plurality of self-drilling fasteners 5 ′ that penetrate horizontal attachment support 30 ′. A continuous snap cover 80 ′ is provided over the channel 80 ′. Caulking C is used as the primary seal to keep air and water from the inverted support channel 60 ′. Systems that use caulking as a primary seal are referred to in the industry as a “wet” system. Among the disadvantages of this design, is that failure of the caulking may result in uncontrolled water entering the building. For example, water may enter through the points at which the fasteners 5 ′ and 70 ′ penetrate the horizontal attachment support 30 ′.
As shown in the horizontal sectional view of FIG. 1, vertical attachment support 2 ′ is screwed into sheathing, such as plywood, or through non-structural sheathing, such as gypsum board, into structural building members using structural screws 6 ′. Vertical corner clips 3 ′ and 40 ′ are used to attach the panel 1000 to the horizontal attachment support 30 ′. The clips 3 ′ and 40 ′ attach only to the return leg 22 of panel and provide no support to the face 23 of the panel. Raised positive return attachment rivets 8 ′ are used to attach the clips. A continuous inverted support channel 4 ′ is secured by a plurality of self-drilling fasteners 5 ′ that penetrate vertical attachment support 2 ′. A continuous snap cover 7 ′ is provided over the channel 4 ′. Caulking C is used as the primary seal to keep air and water from the inverted support channel 4 ′. As above, failure of the caulking may result in uncontrolled water entering the building. For example, water may enter through the points at which the fasteners 5 ′ and 6 ′ penetrate the vertical attachment support 2 ′.
In the MCP system, the horizontal attachment supports 30 ′ and vertical attachment supports 2 ′ used to support the panels 1000 do not have gutters or channels for directing moisture away from the building and do not offer a secondary or failsafe water seal. As discussed above, a disadvantage of this design is that failure of the caulking may result in uncontrolled water entering the building, such as for example through the points at which the fasteners penetrate the horizontal and vertical attachment supports.
Another disadvantage of the MCP system is that, as shown in FIG. 3, the horizontal and vertical attachment supports are not mechanically attached. To the contrary, these members merely abut one another, rather than being mechanically attached as a continuous, integrated structure. Another disadvantage of the MCP system is that each of the vertical attachment supports requires two 18 gauge metal studs for attachment, because these members do not interface mechanically. More generally, because neither the horizontal nor the vertical supports act as structural elements, these members require support from the building structure.
The MCP system uses three different extrusions (i.e., corner clips 3 ′ and 40 ′) to attach the panels 1000 to the horizontal and vertical supports. As shown in FIG. 1, the extrusions on the sides of the panels ( 3 ′) are similar and are continuous along those edges. However, as shown in FIG. 2, the extrusion on the top of the panel ( 40 ′ on the lower panel) is a clip that inserts into a channel in the horizontal attachment support 30 ′, rather than being secured using a fastener 5 ′, as is the extrusion on the bottom of the panel ( 40 ′ on the upper panel). Accordingly, the panel has a defined top and a bottom because of these different extrusions, i.e., the orientation of the panel cannot be changed after the extrusions have been attached to the panel. Each of these three types of extrusions attach to the return leg 22 of the panel through the use of a pop rivet 8 ′ and 9 ′.
One disadvantage of this configuration is that the extrusions do not provide corner support to the face 23 of the panel. This allows the return leg 22 to flex, which applies stress to the 0.020″ aluminum corner (the panel 1000 is typically 3 mm, 4 mm, or 6 mm thick, but when the inside face and the polyethylene core are routed out from the back to form the return leg 22 , all that remains to hold the return leg 22 to the front of the panel 23 is the 0.020″ aluminum face). In addition, because the extrusions are not continuous around the panel (i.e., do not form a continuous frame around the panel), the panel receives no diaphragm support and the face of the panel can distort under stress. Moreover, the three extrusions attach directly to the aluminum sub-system without a thermal break, which allows the transfer of heat and cold through the curtain wall.
In view of the deficiencies of the prior art discussed above, the new and non-obvious enhancements to curtain wall methods and apparatus provided by the present invention include: a dry system having a built in gutter system for rain and condensate, a failsafe moisture proof system, a flexible framework enabling vertical and horizontal support structures to be interchanged (providing flexibility during construction), support braces for the face of the curtain wall, and an alignment process for curtain wall panel alignment during construction.
SUMMARY OF THE INVENTION
The main aspect of the present invention is to provide a non-sequential, dry ACM system having structural mullions which can be mounted to the raw studs of a building.
Another aspect of the present invention is to provide a built in gutter system for the vertical mullions and the horizontal supports, thereby providing a failsafe moisture prevention system.
Another aspect of the present invention is to provide a support for the face of the curtain wall panel.
Another aspect of the present invention is to provide a framework having interchangeable vertical and horizontal mounting options.
Another aspect of the present invention is to provide for symmetrical (versus “handed”) panels to facilitate installation.
Another aspect of the present invention is to provide a method to align curtain wall panels during construction.
Another aspect of the present invention is to provide three curtain wall systems, wherein there exists interchangeable parts for all three systems from the curtain wall face to the bottom of the primary seal.
Other aspects of this invention will appear from the following description and appended claims, reference being made to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 (prior art) is a horizontal sectional view of a Miller-Clapperton Partnership, Inc. (MCP)™ Austell, Ga. curtain wall system.
FIG. 2 (prior art) is a vertical sectional view of the MCP™ system.
FIG. 3 (prior art) is a top perspective view of an assembled MCP™ system.
FIG. 4 (prior art) is a front plan view of the frame of a building.
FIG. 5 is the same view as FIG. 4 with horizontal supports installed.
FIG. 6 is a front plan view of the framework of the preferred embodiment being assembled on the building shown in FIGS. 4 and 5.
FIGS. 6A, and 6 B are front plan views of the joint of the horizontal and vertical supports of FIG. 6 .
FIG. 7 is a cross sectional view of the vertical mullion.
FIG. 8 is a cross sectional view of the horizontal support.
FIG. 9 is a top perspective view of a curtain wall panel of the preferred embodiment.
FIG. 10 is a front plan view of the building shown in FIG. 8 having curtain wall panels being mounted to the framework.
FIG. 11 is a sectional view of the curtain wall panel taken along line 11 — 11 of FIG. 10 .
FIG. 12 is a cross sectional view taken along line 12 — 12 of FIG. 10 .
FIG. 13 is a front plan view of a horizontal support.
FIG. 14 is a top perspective view of vertical support(s) being joined with a horizontal support.
FIG. 15 is an exploded view of the preferred embodiment of the gutters (DPS 4000™) system at one joint.
FIG. 16 is a vertical sectional view showing the horizontal support taken along line 16 — 16 of FIG. 10 .
FIG. 17 is a horizontal sectional view showing the vertical mullion taken along line 17 — 17 of FIG. 10 .
FIG. 18 is a front plan view of the framework showing the operation of the built in gutter system.
FIG. 19 is the same view as FIG. 16 showing the operation of the built in gutter system.
FIG. 20 is a side plan view of the alignment fastener.
FIG. 21 is a front plan view of a panel being installed using an alignment fastener.
FIG. 22 is a cross sectional view of the alignment fastener is use.
FIG. 23 is a vertical sectional view of an alternate embodiment (DPS 3000™) system.
FIG. 24 is a horizontal sectional view of an alternate embodiment (DPS 5000 CW™) system.
FIG. 25 is a horizontal sectional view of an alternate embodiment (DPS 5000 T™) system.
FIG. 26 is an identical view as shown in FIG. 16, but with the preferred embodiment of the gutter and the curtain wall composite assembly.
FIG. 27 is an identical view as shown in FIG. 17, but using the preferred embodiment components shown in FIG. 26, which are shown mounted as vertical gutters.
FIG. 28 is an identical view as shown in FIG. 26, but using a flush joint embodiment.
FIG. 29 is an identical view as FIG. 27, but using a flush joint embodiment.
FIG. 30 is an identical view as FIG. 17, but with the preferred embodiment of the gutter and the curtain wall composite assembly.
FIG. 31 is an identical view as FIG. 16, but with the preferred embodiment components shown in FIG. 30 .
FIG. 32 is an identical view as shown in FIG. 30, but with a flush joint embodiment.
FIG. 33 is an identical view as shown in FIG. 31, but with a flush joint embodiment.
FIG. 34 is a vertical sectional view of a lower termination segment of the preferred embodiment, as illustrated in FIG. 53 .
FIG. 35 is a horizontal sectional view of a lower termination segment of the preferred embodiment, as illustrated in FIG. 53 .
FIG. 36 is vertical sectional view of a lower termination segment(s) of the preferred embodiment, as illustrated in FIG. 53 .
FIG. 37 is an identical view as shown in FIG. 36, but using a recessed joint embodiment.
FIG. 38 is a vertical sectional view of an upper termination segment of the preferred embodiment, as illustrated in FIG. 53 .
FIG. 39 is an identical view as shown in FIG. 38, but using a flush joint embodiment.
FIG. 40 is a horizontal sectional view of an upper termination segment of the preferred embodiment, as illustrated in FIG. 53 .
FIG. 41 is an identical view as shown in FIG. 40, but using a flush joint embodiment.
FIG. 42 is a cross sectional view of gutter 200 showing nominal dimensions.
FIG. 43 is a cross sectional view of gutter 2 showing nominal dimensions.
FIG. 44 is a cross sectional view of termination gutter 4017 showing nominal dimensions.
FIG. 45 is a cross sectional view of termination gutter 4015 showing nominal dimensions.
FIG. 46 is a cross sectional view of flush perimeter extrusion 4012 showing nominal dimensions.
FIG. 47 is a cross sectional view of recessed perimeter extrusion 4008 showing nominal dimensions.
FIG. 48 is a cross sectional view of a pressure channel 4007 showing nominal dimensions.
FIG. 49 is a cross sectional view of a snap cover 4006 showing nominal dimensions.
FIG. 50 is a cross sectional view of a curtain wall composite assembly with a recessed joint embodiment.
FIG. 51 is the identical view as shown in FIG. 50, but using a flush joint embodiment.
FIG. 52 is a perspective view showing the reglet corner clip attached to one member of a pair of perimeter extrusions.
FIG. 53 is a schematic of an imaginary building face showing the locations of components keyed to the above numbered figures.
FIG. 54 is a cross sectional view of an alternate embodiment (DPS 3000™) system, using the same curtain wall composite assembly as used in the FIG. 30 embodiment.
FIG. 55 is a cross sectional view of an alternate embodiment (DPS 3000™) system, using the same curtain wall composite assembly as used in the FIG. 31 embodiment.
FIG. 56 is a cross sectional view of a lower base 13002 of the DPS3000™ embodiment showing nominal dimensions.
FIG. 57 is a cross sectional view of an upper base 3015 of the DPS3000™ embodiment showing nominal dimensions.
FIG. 58 is a vertical cross section of the lower gutter of the preferred embodiment (DPS4000™) with the curtain wall composite assembly shown attached over and through modern stucco known as exterior insulated finish systems (EIFS).
FIG. 59 is a vertical cross section of a horizontal gutter for an alternate embodiment (DPS2500™) incorporating a continuous guttered sub-system.
FIG. 60 is a horizontal cross section of a vertical gutter for an alternate embodiment (DPS2500™) incorporating a continuous guttered sub-system.
FIG. 61 is an identical view as shown in FIG. 59, but utilizing a recessed joint embodiment.
FIG. 62 is an identical view as shown in FIG. 60, but utilizing a recessed joint embodiment.
FIG. 63 is a vertical cross section of a horizontal termination gutter for an alternate embodiment (DPS2500™) incorporating a continuous guttered sub-system.
FIG. 64 is a horizontal cross section of a vertical termination gutter for an alternate embodiment (DPS2500™) incorporating a continuous guttered sub-system.
FIG. 65 is an identical view as shown in FIG. 63, but utilizing a recessed joint embodiment.
FIG. 66 is an identical view as shown in FIG. 64, but utilizing a recessed joint embodiment.
FIG. 67 is a frontal view of the preferred embodiment illustrating the assembly method of installing framework units.
FIG. 68 is a cross sectional view of a splice joint assembly used for joining the framework units of the preferred embodiment.
FIG. 69 is a horizontal cross sectional view of a vertical joint of an alternate embodiment (DPS2000™) illustrating an integrated framework which supports an ACM curtain wall panel that attached to a building structure.
FIG. 70 is a vertical cross sectional view of a horizontal joint of an alternate embodiment (DPS2000™) illustrating an integrated framework which supports an ACM curtain wall panel that attaches to a building structure.
FIG. 71 is an identical view as shown in FIG. 69, but with a flush joint embodiment.
FIG. 72 is an identical view as shown is FIG. 70, but with a flush joint embodiment.
FIG. 73 is a horizontal cross sectional view of a vertical joint of an alternate embodiment (DPS2000™) illustrating clip attachment to the framework.
FIG. 74 is a vertical cross sectional view of a horizontal joint of an alternate embodiment (DPS2000™) illustrating clip attachment to the framework.
FIG. 75 is a horizontal cross sectional view of a vertical joint of an alternate embodiment (DPS2000™) illustrating a termination joint of the framework.
FIG. 76 is a vertical cross sectional view of a horizontal joint of an alternate embodiment (DPS2000™) illustrating a termination joint of the framework.
FIG. 77 is an identical view as shown in FIG. 75, but with a recessed joint embodiment.
FIG. 78 is an identical view as shown in FIG. 76, but with a recessed joint embodiment.
FIG. 79 is a frontal exploded view of a 4-way intersection of the vertical and horizontal frame members illustration connection methods of the framing members.
FIG. 80 is a horizontal cross sectional view illustrating member connections, and framework attachment to the building structure.
FIG. 81 is an identical view as shown in FIG. 79, but exploded.
FIG. 82 is a vertical cross sectional view of a framework assembly illustrating one method of raising it to the building structure.
FIG. 83 is a frontal exploded view of a 4-way intersection of the vertical and horizontal frame members illustrating connection methods of the framing members.
FIG. 84 is a frontal view of a 4-way intersection of the vertical and horizontal frame members illustrating connection methods of the framing members.
FIG. 85 is a cross sectional view of framework joinery illustration member to member connection and framework connection to the building structure.
FIG. 86 is a frontal view of typical framework support of the preferred embodiment and all alternate embodiments. It illustrates four-point vertical frame member to horizontal frame member connections as well as two-point horizontal frame member connections to the building structure.
Before explaining the disclosed embodiment of the present invention in detail, it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown, since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment (referred to as DPS4000™) is shown, e.g., in FIGS. 16 and 17. The system employs aluminum composite material (ACM) panels 1000 as components of an exterior curtain wall or facade of a building. As shown in the vertical sectional view of FIG. 16, a horizontal gutter support 200 is screwed into sheathing (any continuous covering that is attached to the building structure, e.g., plywood, gypsum board, fiberglass board, etc.), or directly into structural building members (structural members that carry the wind load deflections of the building, e.g., structural steel, miscellaneous steel, structural studs, dimensional lumber, concrete, etc.) using structural screws 60 . The structural screws 60 are located outside of the gutters S 1 that on either side of the horizontal joint (i.e., the assembly that connects the panels 1000 to the horizontal gutter support 200 ) so that water leaking into the gutters S 1 cannot seep through to the building structure.
A perimeter corner brace 3 is provided that contacts both the face 23 and the return leg 22 of the panel 1000 to provide support for the 90-degree corner. Sealant 11 is used to maintain air and water integrity and to attach the face 23 of the panel 1000 to the corner brace 3 , providing diaphragm support to the face 23 . A recessed positive return attachment screw 8 is used fasten the return leg 22 of the panel 1000 to the corner brace 3 . The return attachment screw 8 is screwed into self-sealing butyl tape 10 , which provides an air and water seal.
A dry gasket primary seal G is provided to insulate the gutter space S 1 from air and water, but a failure of the gasket G merely allows water into the gutter space S 1 , rather than the building structure. A continuous support channel 4 is secured by a plurality of machine screws 5 without penetrating the horizontal gutter support 200 , which offers a dry, watertight assembly even in the event of failure of the gasket primary seal G. A continuous snap cover 7 is provided to cover the support channel 4 .
The panels 1000 are held to the sub-system by a continuous support channel 4 that is secured by a plurality of machine screws 5 into a screw boss 2004 without penetrating the horizontal gutter support 200 . This configuration allows a dry, watertight assembly to be maintained, even in the event of failure of the gasket primary seal G. The pressure provided by the continuous support channel 4 forces the neoprene gasket G on the bottom of the perimeter extrusion frame 3 against the horizontal gutter support 200 , thereby providing the primary seal without the use of sealants (i.e., a “dry” seal). The dry gasket primary seal G insulates the gutter space S 1 from air and water, but a failure of the gasket G merely allows water into the gutter space S 1 , rather than the building structure. A continuous snap cover 7 is provided to cover the support channel 4 .
As shown in the horizontal sectional view of FIG. 17, a vertical gutter support 2 is screwed into the horizontal gutter support 200 flanges and into the building structure using structural screws 70 to create a guttered sub-system. The structural screws 70 are located outside of the gutters S 2 on either side of the vertical joint (i.e., the assembly that connects panels 1000 to the vertical gutter support 2 ) so that water leaking into the gutters S 2 cannot seep through to the building structure.
A perimeter corner brace 3 is provided contacts both the face 23 and the return leg 22 of the panel 1000 to provide support for the 90-degree corner. As above, sealant 11 is used to maintain air and water integrity and to attach the face 23 of the panel 1000 to the corner brace 3 , providing diaphragm support to the face 23 . A recessed positive attachment screw 90 is screwed into self-sealing butyl tape 10 , which provides an air and water seal.
The perimeter corner braces 3 are joined with the perimeter corner braces 3 of the horizontal gutter support 200 to form a perimeter extrusion frame that is placed inside the panel. Because the same type of extrusions are used on all four sides of a panel, and the extrusions on opposite sides of the panel are identical, the panel can be flipped 180 degrees and still work within the system. Thus, the panels are symmetrical, rather than having a defined orientation.
The perimeter extrusion frame is attached to the return legs 22 of the panel with countersunk fasteners 8 and 90 through non-curing butyl tape 10 that is on the inside return leg 22 to provide a watertight seal. In addition, the perimeter extrusion frame provides corner support eliminating stress to the 0.020″ aluminum corner between the face 23 and return leg 22 of the panel. Thus, the perimeter extrusion frame creates a rigid box top out of the once flexible ACM panel by giving it diaphragm support. The dry gasket primary seal G is continuous around the bottom of the perimeter extrusion frame and provides a thermal break between the panels and the building structure when the frame is placed in the guttered sub-system. As discussed below, the horizontal legs of the perimeter extrusion frame (i.e., perimeter corner braces 3 ) may have weep holes in them to allow condensation to exit to the face of the building.
The panels 1000 are held to the sub-system by a continuous support channel 6 that is secured by a plurality of machine screws 5 into a screw boss 4020 without penetrating the vertical gutter support 2 . This configuration allows a dry, watertight assembly to be maintained, even in the event of failure of the gasket primary seal G. The pressure provided by the continuous support channel 6 forces the neoprene gasket G on the bottom of the perimeter extrusion frame 3 against the vertical gutter support 2 , thereby providing the primary seal without the use of sealants (i.e., a “dry” seal). The dry gasket primary seal G insulates the gutter space S 2 from air and water, but a failure of the gasket G merely allows water into the gutter space S 2 , rather than the building structure. A continuous snap cover 80 is provided to cover the support channel 6 .
As shown in FIGS. 13 and 14, the DPS 4000™ embodiment has a sub-system of integrated horizontal lower gutters 200 (see FIG. 13) and vertical upper gutters 2 (see FIG. 14 ). In most cases, the horizontal lower gutter 200 runs horizontally and attaches to standard-spaced vertical metal studs or other elements of the building structure, allowing for a continuous horizontal gutter. The vertical upper gutter 2 interfaces with the horizontal gutter through factory-milled openings (i.e., cutouts) 54 and join together with fasteners through the overlapping flanges outside of the gutters. The gutters receive a lap sealant when joined together, and the four outside corners of the gutter intersection receive sealant to provide a secondary seal.
Refer to FIGS. 1 and 17 wherein each shows a vertical joint (a cross section of a vertical mullion). The MCP system will allow water to reach the support bolt 6 ′ when the wet sealant C fails as shown by arrow “WET”. Overlapping arm assembly 25 of the corner brace 3 ′ leaks. The preferred embodiment (referred to as DPS4000™) of FIG. 17 has a built in gutter S 2 . A failure of the gasket G only allows water to pass to the gutter S as shown by arrow failsafe. The support bolts 70 are shielded by gutter walls 4001 , 4002 . The MCP™ vertical attachment support 2 ′ has a non-structural (meaning cannot support an intersecting horizontal support) mounting face 20 . Whereas the system 4000 vertical gutter support 2 has a reinforced screw boss 4020 which is a structural component fully integrated with its intersecting horizontal support as shown in FIGS. 6 and 8.
The MCP™ corner brace 3 ′ only supports the route and return member 21 of the curtain wall CW and not the face 23 . Whereas the system 4000 corner brace 3 supports both the face 23 and route and return member 21 of the same curtain wall CW.
Referring to FIG. 3 the MCP™ vertical attachment support 2 ′ requires two parallel studs 50 , 51 to secure it to the exterior of a building via structural screws 53 .
Referring to FIG. 4 the wall 40 of the building has vertical studs 41 which are typically built 16 inches on center. No double studding is required for the present invention in any of its various embodiments.
Referring to FIG. 5, the horizontal supports 200 for the present invention are installed. The builder can choose to install all the horizontal supports 200 before installing the vertical supports 2 , or just a pair of them to build one curtain wall row at a time, either from the bottom up or from the top down. Cutouts 54 receive the flanges 61 of the vertical supports 2 .
Referring to FIGS. 6, 6 A, and 6 B, the horizontal supports 200 fasten to standard 16 inch center studs via fasteners 53 . The horizontal supports 200 may be built in sections and joined in convenient lengths such as six feet at joints 62 . The vertical supports 2 have a flange 61 at each end which integrally fits into the notch 54 of the horizontal flange. A sealant FS is used at the joint(s) 53 to keep moisture away from the building.
Referring to FIG. 7, the vertical support 2 has a base 4059 , a building side 4070 , and a support side 4072 . It must form a curtain wall plane 2019 which is the same plane as 2019 for the horizontal support 200 . Feet 4023 raise the vertical support 2 a distance d 3 away from the frame plane 2029 of the building, such that d 3 +d 4 =d 1 and d 1 >d 4 . The vertical support 2 has a pair of gutter walls 4001 , 4002 , wherein their distal ends 4009 , 4010 define curtain wall plane 2019 . The distal ends 2017 , 2031 of the horizontal support 200 are also co-planar along plane 2019 . The screw boss 4020 has a mounting flange 4021 and a threaded hole 4022 . The mounting holes 4024 are located distally from the gutter walls 4009 , 4010 .
Referring to FIG. 8, the horizontal support 200 has a base 2001 which is mounted to the building. The center longitudinal axis 4060 extends perpendicularly out of the page. The screw boss 2004 has sufficient strength to provide structural support for both the curtain wall panels and the adjoining vertical supports 2 . The screw boss is located centered in the longitudinal axis. It has a central hole 2006 which is threaded. It has a mounting flange 2005 to receive the curtain wall perimeter braces 3 (see FIG. 17 ). The mounting holes 2007 are located distally from the gutter walls 2002 , 2003 . The gutter side walls 2002 , 2003 extend co-planar with the screw boss 2004 away from the mounting side 2008 of the base 2001 , thereby forming a support side 2009 of the horizontal support 200 .
Referring to FIG. 10, the builder in this example has chosen to build the entire framework comprised of vertical and horizontal support elements 2 and 200 before installing the curtain wall panels. The builder has the choice of now hanging the curtain wall panels 1000 from the top down, thereby keeping the building as dry as possible during rain during construction.
Referring to FIGS. 9 and 15, the curtain wall panel(s) is not “handed” rather it is symmetrical from side to side and from top to bottom and fully symmetrical if the curtain wall panel is square. The curtain wall panel 1000 has a face 23 and route and return edges 1001 , 1002 , 1003 , 1004 . As shown in FIG. 15, the perimeter corner braces 3 have a face member 30 which adds strength to the relatively weak face 23 of the curtain wall panel 1000 .
As shown in FIG. 11, corner sealant 11 is applied for air/water integrity. A recessed positive return attachment screw 8 screws into a self sealing gasket (butyl tape) 10 to secure the corner brace 3 to the curtain wall 1000 . The curtain wall 1000 floats on gaskets G which are supported against flanges 2005 and 4021 (see FIGS. 7 and 8) to provide for movement in thermal expansion and construction. Machine screw 5 holds the continuous support panel 6 against the screw boss 4020 . A continuous snap cover 80 provides an aesthetic outside appearance over the screws 5 .
Referring to FIGS. 10, 13 , 14 , and 15 , the preferred embodiment curtain wall apparatus (DPS4000™) is shown partly erected. For alignment integrity among the curtain wall panels 1000 , the builder will normally erect by rows of contiguous panels. A slotted hole 4024 of the vertical gutters allows for additional expansion and contraction.
Referring to FIGS. 11 and 12, the various system 4000 components are shown in a sectional view.
Referring to FIGS. 18 and 19, the rain water W 1 runs down the gutter S 2 to the horizontal support 200 , and then weeps out through the face up 80 (known as a pressure equalized system). A relief cut 1580 cuts through the gutter walls 2002 , 2003 of the horizontal support 200 , thereby allowing condensate drops CD to drain. Water W 2 runs along gutter S 1 to gutter S 2 to the sill flashing or to the next gutter and exits through the weep bole WH and then the joints in the face cap 7 .
Referring to FIG. 19, condensate drops CD (and/or water from the primary seal) flow down the vertical support 2 gutter S 2 into the horizontal support 200 gutter S 1 , and then out weep hole WH to the space S 4 between the curtain wall panels 1000 , as shown by arrow out. Sealant FS is provided between the vertical support 2 flange 61 and the horizontal support 200 notch 54 .
Referring to FIG. 20, an alignment fastener 1735 is shown to have a cylindrical body 1737 ¾ inch in diameter, and preferably made of ABS plastic. A hex washer head machine screw 1736 is threaded through the body 1737 . A stop 1738 is ⅛ inch by 1½ inch diameter, ABS plastic.
FIGS. 21 and 22 show a method for installing a panel 1001 in proper alignment: at least one alignment fastener is secured into an adjoining vertical support screw boss 4020 ; at least two alignment fasteners are secured into an adjoining lower horizontal support screw boss or bosses; the panel 1001 is placed down on the lower alignment fasteners and against the vertical support alignment fastener; the panel is aligned and the alignment fasteners are fastened; the vertical support alignment fastener is removed; the permanent continuous support panel is installed; the lower alignment fasteners are removed; and the horizontal permanent continuous support panel is installed.
Referring to FIG. 23, an alternate embodiment system is shown to have no internal gutters, but offers lower costs. The building 3001 supports a symmetrical vertical and horizontal channel 3002 as part of a dry, non-directional system. An optional gutter OG is shown in dots. The channel 3002 is fastened by fastener 3003 , and sealant 3004 may be used to protect the building 3001 from moisture. Countersunk fasteners 3005 secure a plate 3006 having a screw boss 3007 to the channel 3002 , after the channel 3002 is attached to the building 3001 . The curtain wall panel 1000 has a corner brace 3010 with a smaller face segment 3011 than the preferred embodiment (DPS4000™). A gasket G is placed between the channel 3002 and the corner brackets 3010 . The continuous channel 3012 secures the corner brackets 3010 via fastener 3013 . A facial clip 3014 provides an aesthetic appearance over the fasteners 3013 . It is not a failsafe water prevention system because a failure of G could allow water into space 3049 which would attack sealant 3004 .
Referring to FIG. 24, a horizontal support 5000 CW is designed to attach to a steel angle SA which protrudes from the building slab 5090 . The portion labeled 4000 is equivalent to the preferred embodiment (DPS4000™). However, longer fins 5091 are needed for strength on the horizontal supports; and an integrated tube 5092 is formed as part of the base for the horizontal support 5093 . A bolt 5094 using a shim G secures the integrated tube 5092 to the steel angle SA. Member 5092 is known in the prior art in curtain wall systems, but not in combination with assembly 4000 .
Referring to FIG. 25, an alternate embodiment (referred to as DPS5000™) is shown to have a horizontal support 5850 wherein the assembly 4000 is the same as the preferred embodiment (see FIGS. 16 and 17 ). However, for the first time ever an exterior building structure vertical member VSM can be used to support a curtain wall as shown. The horizontal support base 5850 has (preferably aluminum) fins 5851 , 5852 extending from the building side of the base 5850 . Fasteners (machine screws) 5853 secure the fins 5851 , 5852 to the VSM using a shim GS. No sheath exists on this building. Optional legs 5857 may be used to strengthen the vertical supports.
FIG. 26 is a vertical sectional view of the preferred embodiment (DPS4000™) (see also FIGS. 16 and 17 ). The lower gutter 200 is attached to the upper gutter 2 at right angles through the flanges F 1 , F 2 outside of gutter legs 2002 and 2003 . A continuous X-Y gutter is formed on which the curtain wall composite assembly attaches to the building structure 4003 using fastener 4011 or a similar fastener (see FIG. 53 ). The curtain wall panel 1000 is supported by symmetrical recessed perimeter extrusion 4008 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates recessed perimeter extrusion 4008 , and is sealed by butyl tape 10 . The recessed perimeter extrusion 4008 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners (see FIG. 52 ). The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 200 and upper gutter 2 by machine screw 5 into the integral screw boss of the gutter members. A continuous gasket G 2 which is applied to the bottom of recessed perimeter extrusion 4008 provides a thermal break between the curtain wall composite assembly (FIG. 53 ). The curtain wall composite assembly rests upon 14009 lower gutter bearing leg which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 200 and upper gutter 2 through the screw bosses SB 1 located in the gutters S 1 , S 2 . Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 200 and upper gutter 2 into space S 1 and drain to the bottom of the building elevation. Air pressure equalization is achieved through weep hole 4004 which allows the pressure within the curtain wall composite assembly to equalize with the pressures outside of the curtain wall face 23 .
FIG. 27 is vertical sectional view of the preferred embodiment without a weep hole. The lower gutter 200 is attached to the upper gutter 2 at right angles through the flanges F 1 , F 2 outside of gutter legs 2002 and 2003 to form a continuous gutter on which the curtain wall composite assembly attaches to the building structure 4003 using fastener 4011 (see FIG. 53 ). The curtain wall panel 1000 is supported by symmetrical recessed perimeter extrusion 4008 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates recessed perimeter extrusion 4008 , and is sealed by butyl tape 10 . The recessed perimeter extrusion 4008 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners. The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 200 and upper gutter 2 by machine screw 5 into the integral screw boss SB 1 of the gutter members. A continuous gasket G 2 which is applied to the bottom of recessed perimeter extrusion 4008 provides a thermal break between the curtain wall composite assembly, FIG. 53 . The curtain wall composite assembly rests upon 14009 lower gutter bearing leg which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 200 and upper gutter 2 through the screw bosses SB 1 located in the gutters. Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 200 and upper gutter 2 into space S 1 and drain to the bottom of the building elevation.
FIG. 28 is an identical view as shown in FIG. 26, but utilizing a flush joint embodiment which varies from FIG. 26 by using flush perimeter extrusion 4012 .
FIG. 29 is an identical view as shown in FIG. 27, but utilizing a flush joint embodiment which varies from FIG. 27 by using flush perimeter extrusion 4012 .
FIG. 30 is a horizontal sectional view of the preferred embodiment. The upper gutter 2 is attached to the lower gutter 200 at right angles through the flanges F 3 , F 4 outside of gutter legs 4001 and 4002 which forms a continuous gutter on which the curtain wall composite assembly makes attachment to the building structure 4003 using fastener 4011 (see FIG. 53 ). The curtain wall panel 1000 is supported by symmetrical recessed perimeter extrusion 4008 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates recessed perimeter extrusion 4008 , and is sealed by butyl tape 10 . The recessed perimeter extrusion 4008 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners. The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 200 and upper gutter 2 by machine screw 5 into the integral screw boss of the gutter members. A continuous gasket G 2 which is applied to the bottom of recessed perimeter extrusion 4008 provides a thermal break between the curtain wall composite assembly, FIG. 53 . The curtain wall composite assembly rests upon 4013 upper gutter bearing leg which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 200 and upper gutter 2 through the screw bosses located in the gutters. Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 200 and upper gutter 2 into space S 1 and drain to the bottom of the building elevation.
FIG. 31 is a horizontal sectional view of the preferred embodiment. The upper gutter 2 is attached to the lower gutter 200 at right angles through the flanges outside of gutter legs 4001 and 4002 which forms a continuous gutter on which the curtain wall composite assembly makes attachment to the building structure 4003 using fastener 4011 (see FIG. 53 ). The curtain wall panel 1000 is supported by symmetrical recessed perimeter extrusion 4008 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates recessed perimeter extrusion 4008 , and is sealed by butyl tape 10 . The recessed perimeter extrusion 4008 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners. The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 200 and upper gutter 2 by machine screw 5 into the integral screw boss of the gutter members. A continuous gasket G 2 which is applied to the bottom of recessed perimeter extrusion 4008 provides a thermal break between the curtain wall composite assembly (see FIG. 53 ). The curtain wall composite assembly rests upon 4013 upper gutter bearing leg which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 200 and upper gutter 2 through the screw bosses located in the gutters. Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 200 and upper gutter 2 into space S 1 and drain to the bottom of the building elevation. Air pressure equalization is achieved through weep hole 4004 which allows the pressure within the curtain wall composite assembly to equalize with the pressures outside of the curtain wall face 23 .
FIG. 32 is an identical view as shown in FIG. 30, but utilizing a flush joint embodiment which varies from FIG. 30 by utilizing flush perimeter extrusion 4012 .
FIG. 33 is an identical view as shown in FIG. 31, but utilizing a flush joint embodiment which varies from FIG. 31 by utilizing flush perimeter extrusion 4012 .
FIG. 34 is a vertical sectional view of lower termination gutter 4015 attached to upper gutter 2 at right angles through the flanges outside of gutter leg 2002 which forms a continuous gutter on which the curtain wall composite assembly makes attachment to the building structure 4003 using fastener 4011 or similar (see FIG. 53 ). The curtain wall panel 1000 is supported by symmetrical flush perimeter extrusion 4012 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates flush perimeter extrusion 4012 , and is sealed by butyl tape 10 . The flush perimeter extrusion 4012 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners. The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 4015 and upper gutter 2 by machine screw 5 into the integral screw boss of the gutter members. A continuous gasket G 2 which is applied to the bottom of flush perimeter extrusion 4012 provides a thermal break between the curtain wall composite assembly, FIG. 53 . The curtain wall composite assembly rests upon 14009 lower gutter bearing leg which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 4015 and upper gutter 2 through the screw bosses located in the gutters. Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 4015 and upper gutter 2 into space S 1 and drain to the bottom of the building elevation. The continuous pressure channel 4006 rests upon termination closure 4016 and gasket spacer G 3 . The system is sealed to adjacent materials by perimeter sealant 4014 .
FIG. 35 is an identical view as shown in FIG. 34, but utilizing a recessed joint embodiment which varies from FIG. 34 by utilizing recessed perimeter extrusion 4008 .
FIG. 36 is a vertical sectional view of lower termination gutter 4015 attached to upper gutter 2 at right angles through the flanges F 9 outside of gutter leg 2002 which forms a continuous gutter on which the curtain wall composite assembly, FIG. 53, makes attachment to the building structure 4003 using fastener 4011 . The curtain wall panel 1000 is supported by symmetrical flush perimeter extrusion 4012 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates flush perimeter extrusion 4012 , and is sealed by butyl tape 10 . The flush perimeter extrusion 4012 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners. The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 4015 and upper gutter 2 by machine screw 5 into the integral screw boss of the gutter members. A continuous gasket G 2 which is applied to the bottom of flush perimeter extrusion 4012 provides a thermal break between the curtain wall composite assembly, FIG. 53 . The curtain wall composite assembly rests upon 14009 lower gutter bearing leg which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 4015 and upper gutter 2 through the screw bosses located in the gutters. Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 4015 and upper gutter 2 into space S 1 and drain to the bottom of the building elevation. Air pressure equalization is achieved through weep hole 4004 which allows the pressure within the curtain wall composite assembly to equalize with the pressures outside of the curtain wall face 23 . The continuous pressure channel 4007 rests upon termination closure 4016 and gasket spacer G 3 . The system is sealed to adjacent materials by perimeter sealant 4014 .
FIG. 37 is an identical view as shown in FIG. 36, but utilizing a recessed joint embodiment which varies from FIG. 36 by utilizing recessed perimeter extrusion 4008 .
FIG. 38 is a vertical sectional view of upper termination gutter 4017 attached to lower gutter 200 at right angles through the flanges F 10 outside of gutter leg 4002 which forms a continuous gutter on which the curtain wall composite assembly, FIG. 53, makes attachment to the building structure 4003 using fastener 4011 . The curtain wall panel 1000 is supported by a recessed perimeter extrusion 4008 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates flush perimeter extrusion 4012 , and is sealed by butyl tape 10 . The flush perimeter extrusion 4012 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners. The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 200 and upper gutter 4017 by machine screw 5 into the integral screw boss of the gutter members. A continuous gasket G 2 which is applied to the bottom of recessed perimeter extrusion 4008 provides a thermal break between the curtain wall composite assembly (see FIG. 53 ). The curtain wall composite assembly rests upon 14009 lower gutter bearing leg which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 200 and upper gutter 4017 through the screw bosses located in the gutters. Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 200 and upper gutter 4017 into space S 2 and drain to the bottom of the building elevation. The continuous pressure channel 4006 rests upon termination closure 4016 and gasket spacer G 3 . The system is sealed to adjacent materials by perimeter sealant 4014 .
FIG. 39 is an identical view as shown in FIG. 38, but utilizes a flush joint embodiment which varies from FIG. 38 by utilizing flush perimeter extrusion 4012 .
FIG. 40 is a horizontal sectional view of upper termination gutter 4017 attached to lower gutter 200 at right angles through the flanges F 10 outside of gutter legs 2002 and 2003 which forms a continuous gutter on which the curtain wall composite assembly (see FIG. 53) makes attachment to the building structure 4003 using fastener 4011 . The curtain wall panel 1000 is supported by recessed perimeter extrusion 4008 which acts as a corner brace around all four sides of the curtain wall panel 1000 and seals the corners with corner sealant 11 . It is positively attached to return leg 22 by countersunk fastener 14010 , which penetrates recessed perimeter extrusion 4008 , and is sealed by butyl tape 10 . The recessed perimeter extrusion 4008 is held together at the four corners by the corner reglet clip 4005 providing a framework without the use of fasteners. The curtain wall panel 1000 is attached to the continuous gutter created by lower gutter 200 and upper gutter 4017 by machine screw 5 into the integral screw boss of the gutter members. A continuous gasket G 2 which is applied to the bottom of flush perimeter extrusion 4012 provides a thermal break between the curtain wall composite assembly (see FIG. 53 ). The curtain wall composite assembly rests upon 14009 lower gutter bearing leg, which provides compression and the primary seal. Continuous pressure channel 4007 attaches the curtain wall panel to lower gutter 200 and upper gutter 4017 through the screw bosses located in the gutters. Continuous snap cover 4006 covers pressure channel 4007 covering machine screw 5 . Any water that would penetrate the primary seal would flow into lower gutter 200 and upper gutter 4017 into space S 2 and drain to the bottom of the building elevation. The continuous pressure channel 4006 rests upon termination closure 4016 and gasket spacer G 3 . The system is sealed to adjacent materials by perimeter sealant 4014 .
FIG. 41 is an identical view as shown in FIG. 40, but utilizing a flush joint embodiment which varies from FIG. 40 by utilizing flush perimeter extrusion 4012 .
FIG. 42 shows lower gutter 200 nominal dimensions:
d10 = .246
d11 = .060
d12 = .110
d13 = .071
d14 = .015
d15 = .192
d16 = .018
d17 = .074
d18 = .250
d19 = 4.877
d20 = 3.877
d21 = 2.877
d22 = 1.624
d23 = .500
d24 = .575
d25 = .750
α = 30°
d26 = 1.750
d27 = .020 × 90°
d28 = .050R
P.I. = Point in between
FIG. 43 shows upper gutter 2 nominal dimensions:
d10-d23 are same as FIG. 42
d29 = 1.625
d30 = .450
d34 = .125
d27 = .020 × 90°
d28 = .050R
d31 = .125
d32 = .125
d33 = .125
P.I. = Point in between
α = 30°
FIG. 44 shows upper termination 4017 nominal dimensions:
d 35 =2.909
d 36 =1.625
d 37 =1.000
FIG. 45 shows lower termination 4015 nominal dimensions:
d 35 =2.909
d 37 =1.000
d 38 =1.750
FIG. 46 shows flush perimeter extension 4012 nominal dimensions:
d 39 =0.500
d 40 =0.063
d 41 =0.125
d 42 =1.214
d 43 =0.526
d 44 =0.060
d 45 =0.689
d 46 =0.050R
d 47 =0.020R
d 48 =0.250
FIG. 47 shows Recessed Perimeter Extension 4008 nominal dimensions:
d 39 =0.500
d 40 =0.063
d 41 =0.125
d 43 =0.526
d 44 =0.060
d 45 =0.689
d 46 =0.050R
d 47 =0.020R
d 48 =0.250
d 49 =0.375
d 50 =1.714
FIG. 48 shows pressure channel 4007 nominal dimensions:
d51 = .696
d52 = .537
d53 = .508
d54 = .020 × 90°
d55 = .010R
a1 = 60°
d56 = .030R
d57 = .188
d58 = .249R
d59 = .115R
d60 = .015R
d61 = .730
d62 = .622
d63 = .513
PT = Point
PI = Point in between
d64 = .125
d65 = .417
d66 = .666
Sym = Symmetrical
FIG. 49 shows Snap Cover 4006 nominal dimensions:
d 67 =0.063
d 68 =0.738
d 69 =0.211
d 70 =0.050
d 71 =0.109R
d 72 =0.477
d 73 =0.713
PT=Point
D 74 =0.118
FIGS. 50 and 51 show the common gasket to curtain wall parts which are used interchangeably between the guttered systems shown in FIGS. 27 and 29 respectively, and the non-guttered systems shown in FIGS. 54 and 55. The recessed systems shown in FIGS. 54 and 55 could be interchanged to a flush system as shown in FIG. 51 .
Referring to FIG. 52, a reglet 4005 is a metal clip that adds structural rigidity to corner joints of corner braces 4008 and/or 4112 , where they meet at the inside corners of the curtain wall panels 1000 .
An alternate embodiment of the system (referred to as DPS3000™) is shown in FIGS. 54 and 55 that has no internal gutters (e.g., S 1 and S 2 in FIGS. 16 and 17 ), but offers many of the same features of the preferred embodiment, as well as lower costs. The building 4003 supports a symmetric lower base member 13002 and upper base member 3015 as part of a dry, non-directional system. The lower base member 13002 and upper base member 3015 join at right angles and overlap to create a sub-system framework through the use of fastener 4011 which penetrates the flange legs. The curtain wall panel 1000 has a corner brace 4008 exactly as the preferred embodiment. The corner brace 4008 is comprised of four symmetric extrusions which are joined at the corners with a corner reglet clip 4005 . Prior to corner 4008 being inserted into curtain wall panel 1000 , corner sealant 3117 is applied to all inside corners and butyl sealant 10 is applied in corner brace 4008 at the location of the drilled holes for fastener 1401 . Countersunk fasteners 14010 are inserted through the drilled bole in the curtain wall panel 1000 and through the butyl sealant 10 into corner brace 4008 forming a watertight rigid panel assembly. A gasket G 2 is factory-applied to the bottom of corner brace 4008 . The continuous channel 4007 secures the corner braces 4008 via fastener 53 into screw boss 3007 . A facial clip 4006 provides an aesthetic appearance over the fasteners 53 . The facial clip 4006 can be flush with the face of the curtain wall panel 1000 or recessed ½″ from the face of the curtain wall panel 1000 .
In FIGS. 56 and 57 the nominal dimensions of lower base 13002 and upper base 3015 are:
d100 = .246
d101 = .192 + .000/−.024″
d102 = .060″
d103 = .110″
d104 = .071″
d105 = .015″
d106 = .018″
d107 = .074″
d108 = 1.000″
d109 = .125″
d110 = .020 × 90°
d111 = .500″
d112 = 1.624″
d113 = 3.624
d114 = .575″
d115 = .875″
α = 30°
It can be seen that d 115 +d 109 =d 108 to allow the upper base 3015 to sit atop the flanges F 99 of the lower base 13002 as shown in FIG. 54, and result in a single plane mounting platform shown by dotted lines MP.
FIG. 58 is a vertical cross sectional view of the preferred embodiment (DPS4000™) as shown in FIG. 26, but with varying building structure components and attachment fastener. Sheathing known as exterior insulated finish system (EIFS/Stucco) 4101 is applied to insulation 4102 which is attached to the structural studs 4103 comprises an alternate composite building structure. The framework of lower gutter 200 and upper gutter 2 are attached to the structural studs 4103 using long structural fastener 4100 without crushing the composite building structure comprised of exterior insulated finish system (EIFS) 4101 and insulation 4102 .
FIG. 59 is a vertical cross sectional view of an alternate embodiment (referred to as DPS2500™). Horizontal gutter 2505 is joined with vertical gutter 2506 at right angles and connected through vertical flange leg 2512 and horizontal flange leg 2513 using flange bolt attachment screw 2509 . The pivot point leg 2510 on each side of the horizontal gutter space HGS is milled out at the location of the intersection of the vertical gutter 2505 which forms a continuous guttered framework. The ACM curtain wall panel 1000 has an additional rout 2500 in return leg 22 which fits over pivot point 2510 allowing curtain wall panel face 23 to flex. The curtain wall panel 1000 does not have a corner brace as in the preferred embodiment, but incorporates the framework and continuous gutter embodiments of such. The framework of horizontal gutter 2505 and vertical gutter 2506 is attached to the building structure 4003 using attachment screw 2509 . The curtain wall panel 1000 is placed on the framework and held in place by pressure to the return leg 22 over the pivot point 2510 by pressure channel 2503 which is attached to the gutters 2505 and 2506 by machine screw 2502 into screw boss 2511 . Snap cover 2501 covers machine screw 2502 and pressure channel 2503 . The bottom horizontal return leg 22 of the curtain wall panel 1000 incorporates a weep hole 2504 used to remove moisture from condensation and act as a failsafe against water that may have traveled outside of horizontal gutter space HGS. Water within the horizontal gutter space HGS travels to the vertical gutter space VGS and then downward to the bottom of the framework and out the building.
FIG. 60 is a horizontal cross sectional view of vertical gutter 2506 which is joined with horizontal gutter 2505 at right angles and connected through vertical flange leg 2412 and horizontal flange leg 2513 using flange bolt attachment screw 2509 . The ACM curtain wall panel 1000 has an additional rout 2500 in return leg 22 which fits over pivot point 2510 allowing curtain wall panel face 23 to flex. The curtain wall panel 1000 does not have a corner brace as in the preferred embodiment, but incorporates the framework and continuous gutter embodiments of such. The framework of horizontal gutter 2505 and vertical gutter 2506 is attached to the building structure 4003 using attachment screw 2509 . The curtain wall panel 1000 is placed on the framework and held in place by pressure to the return leg 22 over the pivot point 2510 by pressure channel 2503 which is attached to the gutters 2505 and 2506 by machine screw 2502 into screw boss 2511 . Snap cover 2501 covers machine screw 2502 and pressure channel 2503 . Water that enters the vertical gutter space VGS travels downward to horizontal gutter space HGS and weeps to the face of the curtain wall panel face 23 through weep hole 2504 .
FIG. 61 is an identical view as shown in FIG. 59, but varies by having a recessed joint embodiment whereby the face of the panel 23 extends beyond snap cover 2501 .
FIG. 62 is an identical view as shown in FIG. 60, but varies by having a recessed joint embodiment whereby the face of the panel 23 extends beyond snap hover 2501 .
FIG. 63 is a vertical cross sectional view of the horizontal termination cutter 2507 which connects to vertical gutter 2506 at right angles forming a continuous gutter framework. The pivot leg 2510 is milled out at the location of the vertical gutters to allow water to drain down vertical gutter 2506 to the bottom of the building structure and out the building. The guttered framework is attached to the building structure 4003 using attachment screw 2509 . The curtain wall panel 1000 is placed on the framework and held in place by pressure to the return leg 22 over the pivot point 2510 by pressure channel 2503 , which is attached to the gutters 2506 and 2507 by machine screw 2502 into screw boss 2511 . Snap cover 2501 covers machine screw 2502 and pressure channel 2503 .
FIG. 64 is a horizontal cross sectional view of the vertical termination gutter 2508 which connects to horizontal gutter 2505 at right angles forming a continuous gutter framework. Water that enters the gutter travels downward to the bottom of the building structure and out the building. The guttered framework is attached to the building structure 4003 using attachment screw 2509 . The curtain wall panel 1000 is place on the framework and held in place by pressure to the return leg 22 over the pivot point 2510 by pressure channel 2503 which is attached to the gutters 2505 and 2508 by machine screw 2502 into screw boss 2511 . Snap cover 2501 covers machine screw 2502 and pressure channel 2503 .
FIG. 65 is an identical view as shown in FIG. 63, but varies by having a recessed joint embodiment whereby the face of the panel 23 extends beyond snap cover 2501 .
FIG. 66 is an identical view as shown in FIG. 64, but varies by having a recessed joint embodiment whereby the face of the panel 23 extends beyond snap cover 2501 .
FIG. 67 is a frontal view of the assembly of vertical frame members VFM and horizontal frame members HFM at right angle to create a framework FW. It illustrates the ability to stack one framework FW on top of another against the building structure BS and to join them using a splice joint SJ.
FIG. 68 is a horizontal cross sectional view of splice joint assembly which connects the gutter of one framework to the gutter of another framework by attaching the left splice plate 4105 and right splice plate 4104 to the lower splice plate 4106 to the gutters utilizing splice fastener 4107 . The composite assembly keeps the gutter intact while providing structural support to the framework.
FIG. 69 is a horizontal cross sectional view of the vertical frame member 2107 of an alternate embodiment (referred to as DPS2000™) which is joined at right angles to the horizontal frame member 2106 through the horizontal flange leg 2110 and the vertical flange leg 2111 utilizing flange attachment bolt 2112 . A framework is formed that attaches to building structure 2117 utilizing attachment screw 2113 . The curtain wall panel 1000 is attached to the framework comprised of horizontal frame member 2106 and vertical frame member 2107 by machine screw 2102 which slips through clip slot 2114 in recessed joint corner brace clip 2104 which attaches to return leg 22 and panel stiffener 2115 by clip fastener 2116 . The machine screw 2102 is fastened into screw boss 2105 . Clip slot 2114 allows the curtain wall panel 1000 to float on top of the framework. The primary seal of the system is achieved by the application of backer rod 2101 and sealant 2100 in the recessed joint.
FIG. 70 is a vertical cross sectional view of the horizontal frame member 2106 which is joined at right angles to the vertical frame member 2107 through the horizontal flange leg 2110 and the vertical flange leg 2111 utilizing flange attachment bolt 2112 . They make a framework that is attached to building structure 2117 utilizing attachment screw 2113 . The curtain wall panel 1000 is attached to the framework comprised of horizontal frame member 2106 and vertical frame member 2107 by machine screw 2102 which slips through clip slot 2114 in recessed joint corner brace clip 2104 which attaches to return leg 22 by clip fastener 2116 . Clip slot 2114 allows the curtain wall panel 1000 to float on top of the framework. The primary seal of the system is achieved by the application of backer rod 2101 and sealant 2100 in the recessed joint.
FIG. 71 is an identical view as shown in FIG. 69, but varies by having a flush joint embodiment utilizing flush joint corner brace 2103 whereby the face of the panel 23 is flush with the sealant 2100 .
FIG. 72 is an identical view as shown in FIG. 70, but varies by having a flush joint embodiment whereby the face of the panel 23 is flush with the sealant 2100 .
FIG. 73 is an identical view as shown in FIG. 69, but with one curtain wall panel 1000 eliminated for clarity to illustrate the flush corner brace clip 2103 .
FIG. 74 is an identical view as shown in FIG. 70, but with one curtain wall panel 1000 eliminated for clarity to illustrate the flush corner brace clip 2103 .
FIG. 75 is a horizontal cross sectional view of the vertical termination frame member 2109 which is joined at right angles to the horizontal frame member 2106 through the horizontal flange leg 2110 and the vertical flange leg 2111 utilizing flange attachment bolt 2112 . They make a framework that is attached to building structure 2117 utilizing attachment screw 2113 . The curtain wall panel 1000 is attached to the framework comprised of horizontal frame member 2106 and vertical termination member 2109 by machine screw 2102 which slips through clip slot 2114 in recessed joint corner brace clip 2104 which attaches to return leg 22 by clip fastener 2116 . Clip slot 2114 allows the curtain wall panel 1000 to float on top of the framework. The primary seal of the system is achieved by the application of backer rod 2101 and sealant 2100 in the flush joint.
FIG. 76 is a vertical cross sectional view of the horizontal termination frame member 2108 which is joined at right angles to the vertical frame member 2107 through the horizontal flange leg 2110 and the vertical flange leg 2111 utilizing flange attachment bolt 2112 . They make a framework that is attached to building structure 2117 utilizing attachment screw 2113 . The curtain wall panel 1000 is attached to the framework comprised of horizontal termination member 2108 and vertical frame member 2107 by machine screw 2102 which slips through clip slot 2114 in recessed joint corner brace clip 2104 which attaches to return leg 22 by clip fastener 2116 . Clip slot 2114 allows the curtain wall panel 1000 to float on top of the framework. The primary seal of the system is achieved by the application of backer rod 2101 and sealant 2100 in the flush joint.
FIG. 77 is an identical view as shown in FIG. 75, but varies by having a recessed joint embodiment utilizing recessed joint corner brace 2104 whereby the sealant 2100 is recessed with respect to the face of the panel 23 .
FIG. 78 is an identical view as shown in FIG. 74, but varies by having a recessed joint embodiment utilizing recessed joint corner brace 2104 whereby the sealant 2100 is recessed with respect to the face of the panel 23 .
FIG. 79 is an exploded frontal view showing vertical frame member 2107 and horizontal frame member 2106 illustrating connection of flange bolts 2112 from vertical flange leg 2111 and horizontal flange leg 2110 . Fastener 2113 illustrates connection of the framework comprised of vertical frame member 2107 and horizontal frame member 2106 to the building structure.
FIG. 80 is a cross sectional view of framework comprised of vertical frame member 2107 and horizontal frame member 2106 illustrating frame connection using flange bolt 2112 and frame to building structure 2117 attachment utilizing fastener 2113 .
FIG. 81 is an frontal view showing vertical frame member 2107 and horizontal frame member 2106 illustrating connection of flange bolts 2112 from vertical flange leg 2111 and horizontal flange leg 2110 . Fastener 2113 illustrates connection of the framework comprised of vertical frame member 2107 and horizontal frame member 2106 to the building structure.
FIG. 82 is a vertical cross sectional view of a framework assembly consisting of vertical frame member 2107 and horizontal frame member 2106 with flanges 2110 and 2111 illustrating one method of attaching a framework to the building structure 2117 .
FIG. 83 is an exploded frontal view for alternate embodiment DPS2500™ of vertical frame member 2506 and horizontal frame member 2505 illustrating assembly connections through flanges 2512 and 2513 utilizing flange connection 2514 . The assembled connection is attached to the building structure utilizing fastener 2509 . Frame 84 is a frontal view of vertical frame member 2506 and horizontal frame member 2505 illustrating assembly connections through flanges 2512 and 2513 utilizing flange connection 2514 . The assembled connection is attached to the building structure utilizing fastener 2509 .
FIG. 85 is a cross sectional view of framework consisting of vertical frame member 2506 and horizontal frame member 2505 illustrating connection through flange 2512 and flange 2511 with flange bolt 2514 . The curtain wall panel 1000 is attached to the framework by attaching return leg 22 to pivot leg 2510 and held in place by pressure channel 2503 by fastener 2502 and covered by snap cover 2501 . The frame assembly attaches to the building structure 4003 .
FIG. 86 shows horizontal frame members HFM joined to vertical frame members VFM at right angles. The left flange leg LFL and right flange leg RF of the vertical frame members VFM overlap the lower flange leg LF and the upper flange leg UF of the horizontal frame members HFM above and below the vertical extents VE of the curtain wall panel, and are connected utilizing bolts and nuts at the intersection. Upon the horizontal frame members HFM and vertical frame members VFM being bolted together, it comprises the framework FW. The framework FW is placed against the building structure BS and joined through the horizontal frame members HFM utilizing building fasteners BF 1 in the upper flange leg UF and BF 2 in the lower flange leg LF, as required by wind loading requirements, between the horizontal extents HE of the curtain wall panel. The vertical bearing surface VBS and horizontal bearing surface HBS prevent the framework FW from crushing any sheathing SH, such as gypsum board or insulation, which may be attached over the building structure BS. The vertical spacing VS of the building fasteners BF 1 and BF 2 provide constant force to the flanges UF, LF, RF, LFL of the framework FW to the building structure BS while also providing for two connection points in lieu of one. Nominal Dimensions are:
A 1 =4′×5′=20′
A 2 =2(4′)×(0.40)+2(5′)×(0.40)=7.12
A 2 over A 1 =0.36
A=4′0
B=5′0
C=4′0
D=5′0
E=4′0
F=5′0
G=4.750″
H=4.750″
Although the present invention has been described with reference to preferred embodiments, numerous modifications and variations can be made and still the result will come within the scope of the invention. No limitation with respect to the specific embodiments disclosed herein is intended or should be inferred. | A curtain wall (ACM) system has vertical mullions and horizontal supports which provide a dry as well as a structural system for non-sequential construction of curtain wall exteriors. Internal gutters offer a failsafe moisture proof system. The horizontal and vertical framework members may be mounted in the reverse orientation for special exterior wall configurations. Individual panels can be replaced without sealants or tear down of neighboring panels. A face support for the thin ACM panels is provided. Thermal expansion is addressed with a floating panel on a track design. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims priority under 35 USC 119 from Japanese Patent Application No. 2009-272471, filed Nov. 30, 2009.
BACKGROUND
1. Technical Field
The present invention relates to an information retrieval method, a computer readable medium and an information retrieval apparatus.
2. Related Art
There has been proposed technology wherein information is retrieved with retrieval conditions being the semantic relation between sentence elements such as a word and a phrase, and a concept stipulated by the semantic relation.
SUMMARY OF THE INVENTION
According to an aspect of the invention, a computer readable medium stores a program causing a computer to execute a process for retrieving information. The process includes an extracting process, an executing process, a first creating process, a second creating process, a determining process.
The extracting process extracts, from a first composition that is an object to be searched for and that includes first sentence elements and a second composition that indicates a retrieval condition and that includes second sentence elements, the first sentence elements, the second sentence elements, and sentence element relations indicating relations between the first sentence elements and relations between the second sentence elements.
The executing process executes a syntactic analysis with respect to the first composition and the second composition;
The first creating process creates composition index information indicating the first sentence elements and the sentence element relations between the first sentence elements based on a result of the syntactic analysis;
The second creating process creates retrieval condition information indicating the second sentence elements and the sentence element relations between the second sentence elements based on the result of the syntactic analysis; and
The determining process determines the first composition corresponding to the composition index information as a retrieval result for the retrieval condition, when a pair of the sentence elements included in the retrieval condition information and having the sentence element relation of predetermined property corresponds to a pair of the sentence elements included in the composition index information.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention will be described in detail based on the following figures, wherein:
FIG. 1 is a schematic diagram showing an example of an information retrieval system in the first exemplary embodiment of the present invention;
FIG. 2 is a schematic diagram showing an example of an information retrieval apparatus;
FIG. 3 is a schematic diagram showing an example of a document;
FIGS. 4A and 4B are schematic diagrams each showing an example of the syntactic analysis result of the document;
FIG. 5 is a schematic diagram showing an example of composition index information;
FIG. 6 is a schematic diagram showing an example of a question sentence which is accepted by question sentence acceptance means;
FIG. 7 is a schematic diagram showing an example of the syntactic analysis result of the question sentence;
FIG. 8 is a schematic diagram showing an example of retrieval condition information;
FIG. 9A is a flow chart showing an operating example of the information retrieval system;
FIG. 9B is a flow chart showing an operating example of the information retrieval system;
FIG. 10 is a schematic diagram showing another example of a question sentence which is accepted by question sentence acceptance means in the second exemplary embodiment;
FIG. 11 is a schematic diagram showing an example of the syntactic analysis result of the question sentence; and
FIG. 12 is a schematic diagram showing another example of retrieval condition information.
DETAILED DESCRIPTION
[First Exemplary Embodiment]
(Configuration of Information Retrieval System)
FIG. 1 is a schematic diagram showing an example of the information retrieval system of the present invention.
This information retrieval system 5 is configured by connecting among an information retrieval server device 1 , a document database 2 and a terminal device 3 so as to be communicable with one another through a network 4 .
The information retrieval server device 1 is an information processing device having electronic components, such as a CPU (Central Processing Unit) and a storage unit for retrieving information responsive to a question sentence.
The document database 2 stores therein a plurality of documents 20 as an object to be searched for. The documents 20 are files created by a word processor, and a spreadsheet program or the like program, HTML documents, etc. A composition which is configured of one or more sentences shall be contained in each of the files mentioned above. Besides, an image file or a music file which contains a composition in its header or the like may be set as the document 20 to-be-retrieved.
The terminal device 3 is a device for accessing the information retrieval server device 1 and inputting a question sentence, and for displaying a retrieval result for the question sentence. This terminal device 3 has a manipulation unit for inputting a manipulation, a display unit such as a liquid-crystal display, and a control unit including electronic components such as a CPU and a storage unit. Incidentally, the terminal device 3 may be, for example, a personal computer, a PDA (Personal Digital Assistant), or a portable telephone. Besides, although one terminal device 3 is shown in FIG. 1 , a plurality of terminal devices may be included in the information retrieval system.
The network 4 may be a LAN (Local Area Network), the Internet, or the like, and it may be either wired or wireless.
Here, the “question sentence” is a composition which is configured of a natural language, and it may have any length or any number of sentences. Besides, the “retrieval result” is a word, a sentence or a composition which is configured of the natural language, a document which contains the composition, a link for the document, or the like.
FIG. 2 is a schematic diagram showing an example of the information retrieval server device 1 .
The information retrieval server device 1 includes a control unit 10 which is configured of a CPU etc. and which controls individual portions and runs various programs, a storage unit 11 which is configured of a storage medium such as an HDD (Hard Disk Drive) or a flash memory and in which information is stored, and a communication unit 12 which communicates with the exterior through the network 4 .
The control unit 10 runs an information retrieval program 11 A shown in FIG. 2 as will be stated later, thereby to function as document acquisition means 10 A, syntactic analysis means 10 B, composition index creation means 10 C, question sentence acceptance means 10 D, retrieval condition creation means 10 E and retrieval execution means 10 F.
The document acquisition means 10 A accesses the document database 2 through the network 4 , so as to acquire a document 20 .
The syntactic analysis means 10 B analyzes the syntax of a sentence which constitutes a composition contained in the document 20 , or a question sentence which will be stated later.
The composition index creation means 10 C creates composition index information 11 B from the syntax of the sentence which is contained in the document 20 analyzed by the syntactic analysis means 10 B
The question sentence acceptance means 10 D accepts the question sentence inputted to the terminal device 3 , through the network 4 .
The retrieval condition creation means 10 E creates retrieval condition information 11 C from the syntax of the question sentence analyzed by the syntactic analysis means 10 B.
The retrieval execution means 10 F compares the composition index information 11 B and the retrieval condition information 11 C, so as to retrieve a sentence, a composition or a document containing the composition which agrees with a condition.
The storage unit 11 stores therein the information retrieval program 11 A which causes the control unit 10 to operate as the respective means stated above, the composition index information 11 B which is outputted from the composition index creation means 10 C, and the retrieval condition information 11 C which is outputted from the retrieval condition creation means 10 E.
(Operation of Information Retrieval System)
Now, the operation of the information retrieval system 5 will be described separately for (1) the operation of creating composition index information, (2) the operation of inputting a question sentence, and (3) the operation of retrieving information, with reference to FIGS. 1 to 9B .
Incidentally, (1) the creation of the composition index information should desirably be previously done before (3) the execution of the retrieval of the information, for the purpose of enhancing a retrieval rate, and it is done regularly, for example, every second day, or when a new document has been added into the document database 2 . Besides, (1) the creation of the composition index information may be executed with a trigger being (3) the execution of the retrieval of the information.
(1) Operation of Creating Composition Index Information
FIG. 9A is a flow chart showing an operating example of the information retrieval system 5 .
First, the document acquisition means 10 A acquires documents 20 from the document database 2 in succession (S 1 ). Incidentally, on this occasion, the document for which composition index information has already been created may be discriminated by, for example, erecting a flag indicative of the information creation and be skipped without being acquired.
FIG. 3 is a schematic diagram showing an example of the acquired document 20 configured of Japanese.
A composition 20 A is an example of a composition contained in the document 20 , and it has a composition consisting of a first sentence 20 a meaning “The necessity of an influenza vaccine rises” and a second sentence 20 b meaning “Company B succeeds in the development of the vaccine ahead of the major pharmaceutical companies”. Incidentally, although the composition of the document 20 A is constituted by the two sentences in the example shown in the figure, it may be constituted by one sentence or three or more sentences.
Subsequently, the syntactic analysis means 10 B executes the syntactic analysis of the composition contained in the acquired composition 20 A and outputs a compositional syntactic analysis result (S 2 ).
FIGS. 4A and 4B are schematic diagrams each showing an example of the compositional syntactic analysis result.
The compositional syntactic analysis result 200 A shown in FIG. 4A is a result obtained in such a way that the first sentence 20 a of the composition 20 A has been subjected to the syntactic analysis by the syntactic analysis means 10 B, and this result has a plurality of sentence elements 200 a to 200 d, and sentence element relations 200 i to 200 k which indicate the qualifying relations etc. among the sentence elements 200 a to 200 d . The composition is divided by the compositional syntactic analysis, and the sentence elements are individual character strings which are the results of the division.
Incidentally, the numeral with colon in each of the sentence elements 200 a to 200 d indicates the order in which the pertinent sentence element has appeared in the composition. Besides, the arrow of each of the sentence element relations 200 i to 200 k is depicted from the word of the argument of the pertinent relation to a head.
A compositional syntactic analysis result 201 A shown in FIG. 4B is a result obtained in such a way that the second sentence 20 b of the composition 20 A has been subjected to the syntactic analysis by the syntactic analysis means 10 B, and it has a plurality of sentence elements 201 a to 201 h , and sentence element relations 201 i to 201 o which indicate the qualifying relations etc. among the sentence elements 201 a to 201 h.
The compositional syntactic analysis results are obtained for the sentences contained in the composition, that is, for the first sentence 20 a and the second sentence 20 b, respectively. Besides, the syntactic analyses are concretely made by executing syntactic-semantic analyses for the first sentence 20 a and the second sentence 20 b , so as to divide the sentences into words and to analyze the qualifications and semantic relations of the words. Besides, the syntactic-semantic analyses are executed using a case frame lexicon, etc. not shown.
Subsequently, the composition index creation means 10 C creates composition index information on the basis of the compositional syntactic analysis results 200 A and 201 A (S 3 ). The composition index information is created every composition.
FIG. 5 is a schematic diagram showing an example of the composition index information 11 B.
Composition index information 110 B is an example of the composition index information 11 B, and it is information created by the composition index creation means 10 C from the compositional syntactic analysis results 200 A and 201 A shown in FIGS. 4A and 4B , respectively. Incidentally, the relation between “Company B: 1 ” and “(make) development: 1 ” may not be directly read from the compositional syntactic analysis result 200 A, but “development: 1 ” preceding “succeed: 1 ” is a noun based on the irregular conjugation verb of the s series in the Japanese language, and the subject of “succeed: 1 ” also becomes the subject of “(do) development: 1 ”, so that the composition index creation means 10 C adds the relation of both the words as a relation P 11 in the composition index information 110 B.
The composition index information 110 B has a relation No. column 110 a which contains the identifiers of sentence element relations, a sentence No. column 110 b which indicates the Nos. of sentences in a document, a sentence element relation column 110 c which indicates the relations between sentence elements, a sentence element “1” column 110 d which indicates the heads of the sentence elements, a sentence element “2” column 110 e which indicates the arguments of the sentence elements, and a relation property column 110 f which indicates the properties of the sentence element relations.
The relation property column 110 f is determined to be “dynamic” for a verb-like usage which is decided using a predetermined case frame lexicon, etc. from the sentence element relation, and to be “static” for any other. Incidentally, the “case frame lexicon” is a lexicon in which the case relations of verbs are described, and a subject and an object are presumed from the cases of the verbs.
Subsequently, the composition index creation means 10 C additionally stores the created composition index information 110 B in the composition index information storage area 11 B of the storage unit 11 , together with the identification information of the document 20 (S 4 ). The composition index information 110 B is created as to all the documents 20 which are stored in the document database 2 .
(2) Operation of Inputting Question Sentence
Subsequently, a user who makes a request for the retrieval of information inputs a desired question sentence by manipulating the manipulation unit of the terminal device 3 . The control unit of the terminal device 3 requests the information retrieval server device 1 to execute the retrieval, through the network 4 , and it transmits the question sentence inputted by the user.
(3) Operation of Retrieving Information
FIG. 9B is a flow chart showing an operating example of the information retrieval system 5 .
First, the question sentence acceptance means 10 D accepts the question sentence from the terminal device 3 (S 11 ).
FIG. 6 is a schematic diagram showing an example of the question sentence in Japanese.
The question sentence 30 A is a composition created in such a way that the user inputted the question sentence to the manipulation unit of the terminal device 3 , and it means “What is the company which developed the vaccine of influenza?” Incidentally, although the question sentence 30 A is constituted by one sentence in the example shown in the figure, it may be a composition constituted by two or more sentences.
Subsequently, the syntactic analysis means 10 B subjects the acquired question sentence 30 A to a syntactic analysis and outputs a question-sentence syntactic analysis result (S 12 ). When the question sentence is the composition constituted by the plurality of sentences, the syntactic analysis is executed every sentence.
FIG. 7 is a schematic diagram showing an example of the question-sentence syntactic analysis result.
The question-sentence analysis result 300 A is a result obtained in such a way that the question sentence 30 A has been syntactically analyzed by the syntactic analysis means 10 B, and it has a plurality of sentence elements 300 a to 300 d , and sentence element relations 300 i to 300 k which indicate the qualifying relations among the sentence elements 300 a to 300 d.
Subsequently, the retrieval condition creation means 10 E creates retrieval condition information shown in FIG. 8 , on the basis of the question-sentence syntactic analysis result 300 A (S 13 ). Incidentally, the retrieval condition information is created as one retrieval condition information even in a case where the question sentence is constituted by a plurality of sentences.
FIG. 8 is a schematic diagram showing an example of the retrieval condition information.
The retrieval condition information 110 C is an example of the retrieval condition information 11 C, and it is information created by the retrieval condition creation means 10 E from the question-sentence syntactic analysis result 300 A shown in FIG. 7 .
Likewise to the composition index information 110 B, the retrieval condition information 110 C has a relation No. column 110 a , a sentence No. column 110 b , a sentence element relation column 110 c , a sentence element “1” column 110 d , a sentence element “2” column 110 e , and a property column 110 f.
Subsequently, the retrieval execution means 10 F compares one composition index information 110 B of the plurality of composition index information items created in correspondence with the plurality of documents 20 stored in the database 2 , with the retrieval condition information 110 C (S 14 ). Concretely, those sentence elements of the information items 110 B and 110 C which agree in the sentence element relation column 110 c and the sentence element “1” column 110 d are extracted.
Subsequently, regarding the sentence elements whose relation property columns 110 f are “dynamic”, among the sentence elements extracted at the step S 14 , as to which the sentence element relation column 110 c and either the sentence element “1” column 110 d or the sentence element “2” column 110 e agree, the document corresponding to the composition index information 110 B is included in the retrieval result (S 16 ) in the existence of the sentence elements both of which agree in either the sentence element “2” column 110 e or the sentence element “1” column 110 d (S 15 ; Yes).
Regarding, for example, Q 1 in the retrieval condition information 110 C shown in FIG. 8 , the relation property is “dynamic”, and a subject for “develops: 1 ” is “company: 1 ”. Here, as regards “company” and “company-B”, when it has been found that the subordinate concept of “company: 1 ” is “company-B”, from a word lexicon for the syntactic-semantic analysis, not shown, the retrieval execution means 10 F may judge that Q 1 agrees with P 11 in the composition index information 110 B shown in FIG. 5 .
Besides, in a case at the step S 15 where the sentence elements agree in the sentence element relation column 110 c and the sentence element “1” column 110 d , and where the relation property column 110 f is “dynamic”, but where the sentence elements do not agree in the sentence element “2” column 110 e (S 15 ; No), the corresponding document is not included in the retrieval result. It is judged that Q 1 and P 11 , for example, do not agree.
Subsequently, of the sentence elements agreeing in the sentence element relation column 110 c and the sentence element “1” column 110 d as have been extracted at the step S 14 , ones as to which the relation property column 110 f is “static” (S 16 ; Yes) may agree in either the sentence element “1” column 110 d or the sentence element “2” column 110 e . By way of example, “vaccine” of Q 2 is “dynamic” in the relation property, and hence, the sentence elements need to agree in “develop” of the sentence element and “object of adnominal “of”” of the sentence element relation. However, “vaccine” of Q 3 is “static” in the relation property, and hence, the sentence elements are judged to agree, subject to the agreement thereof in “vaccine” despite the disagreement thereof in “influenza”. Then, the step S 15 or S 16 is followed by a step S 17 .
Owing to the above operations, the retrieval execution means 10 F judges that Q 1 Q 2 and Q 3 shown in FIG. 8 agree with P 11 , P 10 and P 3 shown in FIG. 5 , respectively, and it includes the first sentence 20 a and the second sentence 20 b in the retrieval result (S 17 ) because the sentence Nos. of P 11 , P 10 and P 3 are “2”, “2” and “1”, respectively.
The above steps S 14 to S 17 are executed for all the composition index information items 11 B (S 18 ). The corresponding sentences (or compositions each consisting of a plurality of sentences) in the document are rearranged in the order of the number of the sentences as to which all the sentence elements having the dynamic sentence element relations have agreed and the number of the sentences as to which the sentence elements having the static sentence element relations have agreed, and the rearranged sentences are displayed as the retrieval result (S 19 ).
Incidentally, regarding the rearrangement of the document, priority may be given to either the agreement of the dynamic sentence element relation or the agreement of the static sentence element relation, and it is also allowed to employ a configuration in which the priority may be selectively set by the user.
Besides, regarding the display of the retrieval result, the whole document may be displayed, only the composition in the document may be displayed, the sentence in the composition as has agreed in the sentence element may be highlighted and displayed, or only the sentence which has agreed in the sentence element may be extracted and displayed. In the case where the document is the image or music file, the document itself is displayed together with the sentence elements having agreed.
[Second Exemplary Embodiment]
In an information retrieval system according to the second exemplary embodiment of the present invention, documents 20 and a question sentence are configured of a language other than Japanese, for example, of English, and syntactic analysis means 10 B, composition index creation means 10 C and retrieval condition creation means 10 E are configured so as to conform to the other language. The others are configured in the same manner as in the first exemplary embodiment. Incidentally, an information retrieval system may well handle documents 20 and question sentences which contain a plurality of languages. Besides, operations to be stated below are similar to the operations in FIG. 9B .
First, the question sentence acceptance means 10 D accepts the question sentence from the terminal device 3 (S 11 ).
FIG. 10 is a schematic diagram showing an example of the question sentence which is accepted by the question sentence acceptance means 10 D in the second exemplary embodiment.
The question sentence 31 A is a composition inputted and created in such a way that a user manipulates the manipulation unit of the terminal device 3 , and it has a sentence stated in English; “What department is taking measures to the influenza?”
Subsequently, the syntactic analysis means 10 B syntactically analyzes the acquired question sentence 31 A and outputs a question-sentence syntactic analysis result (S 12 ).
FIG. 11 is a schematic diagram showing an example of the question-sentence syntactic analysis result.
The question-sentence analysis result 301 A is a result obtained in such a way that the question sentence 31 A has been syntactically analyzed by the syntactic analysis means 10 B, and it has a plurality of sentence elements 301 a to 301 d consisting chiefly of words, and sentence element relations 301 i to 301 k indicating the qualifying relations among the sentence elements 301 a to 301 d.
Subsequently, the retrieval condition creation means 10 E creates retrieval condition information on the basis of the question-sentence syntactic analysis result 301 A (S 13 ).
FIG. 12 is a schematic diagram showing an example of the retrieval condition information.
The retrieval condition information 111 C is the example of the retrieval condition information 11 C, and it is information created from the question-sentence syntactic analysis result 301 A shown in FIG. 11 , by the retrieval condition creation means 10 E.
Likewise to the composition index information 110 B, the retrieval condition information 111 C has a relation No. column 110 a , a sentence No. column 110 b , a sentence element relation column 110 c , a sentence element “1” column 110 d , a sentence element “2” column 110 e and a property column 110 f.
As stated above, even in the case of the language other than Japanese, the retrieval condition information 111 C is created on the basis of the operations shown in FIG. 9B , and also the composition index information 11 B is subsequently created on the basis of the operations shown in FIG. 9A . Further, the retrieval execution means 10 F operates in the same manner as in the first exemplary embodiment and obtains answers corresponding to the desired question sentence, from the document 20 .
[Other Exemplary Embodiments]
Incidentally, the present invention is not restricted to the foregoing exemplary embodiments, but it is capable of various modifications within a scope not departing from the purport of the present invention. In a case, for example, where structured compositions such as chapter compositions are subjects to-be-retrieved, a retrieval range and a retrieval result may be restricted in such a way that the composition index creation means 10 C creates the composition index information 11 B every chapter. Besides, the retrieval execution means 10 F may well restrict the retrieval range and output the retrieval result every chapter.
Besides, the document acquisition means 10 A, the syntactic analysis means 10 B, the composition index creation means 10 C, the question-sentence acceptance means 10 D, the retrieval condition creation means 10 E and the retrieval execution means 10 F which are used in the exemplary embodiments may be loaded from a CD-ROM or the like storage medium into the storage unit within the apparatus, or they may be downloaded from a server apparatus or the like connected to the Internet or the like network, into the storage unit within the apparatus. Besides, some or all of the means used in the exemplary embodiments may be incarnated by hardware such as ASIC.
The foregoing description of the exemplary embodiment of the present invention has been provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and various will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling other skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents. | According to an aspect of the invention, a computer readable medium stores a program causing a computer to execute a process for retrieving information. The process includes an extracting process, an executing process, a first creating process, a second creating process, a determining process. The extracting process extracts, from a first composition that is an object to be searched for and that includes first sentence elements and a second composition that indicates a retrieval condition and that includes second sentence elements, the first sentence elements, the second sentence elements, and sentence element relations indicating relations between the first sentence elements and relations between the second sentence elements. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for the production of antimony trioxide.
2. Description of the Prior Art
Antimony trioxide, also known as antimonous oxide and/or Sb 2 O 3 , is a known compound useful in the manufacture of paints, plastics, ceramics, and the like. The principal utility of antimony trioxide is as a flame retardant.
Conventionally, antimony trioxide is produced by high temperature roasting/smelting processes using antimony trisulfide concentrate as the starting material. Antimony trisulfide concentrate contains large amounts (e.g. >80% by weight) of antimony trisulfide. The following is the principal reaction that occurs during conventional roasting/smelting:
2Sb.sub.2 S.sub.3 +9O.sub.2 →2Sb.sub.2 O.sub.3 +6SO.sub.2 ↑
One of the principal concerns in conventional production of antimony trioxide is the concurrent production of SO 2 . Specifically, unabated release of this sulfur dioxide is known to lead to acid production which has significant detrimental effects on the environment. Thus, it is necessary to scrub sulfur dioxide emissions (for example by flue gas desulfurization technology) produced during manufacture of antimony trioxide. In a typical commercial plant using this conventional technology for production of antimony trioxide, the capital cost of scrubbing sulfur dioxide emissions can approach or even exceed two orders of magnitude more than the capital cost of the process which produces antimony trioxide.
Thus, not surprisingly, the capital cost of a commercially viable conventional roasting/smelting process can be in excess of CDN$20 million. Further, conventional roasting/smelting processes lack the flexibility to produce alternate crystalline forms of antimony trioxide (i.e. senarmontite or valentinite) or to vary the particle size distribution of the product.
Recent attempts to solve these problems include: (i) a high temperature chlorination coupled with calcium chloride reactant (Bureau de Recherches Geologiques et Minieres in Orleans, France), and (ii) high temperature chlorination coupled with hydrochloric acid reactant (Preussag GB Erdol und Chemie). Approach (i) is deficient since the need to conduct the reaction at approximately 500° C. results in a very corrosive reaction system necessitating the use of reactors made of specialized titanium alloys--this dramatically increases the capital and process maintenance costs of the plant. Approach (ii) is deficient since sulfur from the starting material is converted to hydrogen sulfide (H 2 S) which must be scrubbed or otherwise treated to obviate or mitigate a negative impact on the environment--this also dramatically increases the capital and process maintenance costs of the plant.
Thus, while the commercial demand for antimony trioxide remains high, there is little room in an environmentally conscious world for a conventional roasting/smelting process which converts antimony trisulfide to antimony trioxide. Further, the recent attempts at improved technologies have met with little or no commercial success.
Accordingly, the art is in need of a process for production of antimony trioxide which avoids the problems of the prior art.
It would be desirable to have an improved process for production of antimony trioxide. Ideally, the improved process: (i) could be implemented at relatively low capital cost, (ii) would avoid the production of environmentally hazardous compounds such as SO 2 and H 2 S, (iii) could be conducted at or near the source of antimony trisulfide, and/or (iv) would minimize the need for large quantities of virgin reagents (i.e. reagents used in the improved process could be readily recycled to provide a closed or near-closed loop reaction system).
SUMMARY OF THE INVENTION
It is an object of the present invention to obviate or mitigate at least one of the above-identified disadvantages of the prior art.
Accordingly, the present invention provides a process for the production of antimony trioxide comprising the steps of:
(i) reacting antimony trisulfide with iron (III) chloride to produce antimony trichloride; and
(ii) hydrolyzing antimony trichloride to produce antimony trioxide.
Thus, in the present process antimony trisulfide is reacted with iron (III) chloride to produce an antimony trichloride intermediate which can be readily converted to antimony trioxide. The present process is ideally suited to utilize antimony trisulfide concentrate as a starting material. As is known in the art, antimony trisulfide concentrates may be produced by flotation techniques to produce a concentrate material which contains at least about 70% by weight, preferably at least about 90% by weight, antimony trisulfide. The remainder of the concentrate comprises silica and heavy metal impurities.
As will be described in more detail hereinbelow, a key advantage of the present process is that the production of environmentally hazardous by-products (i.e. materials which can not be recovered and must be treated (at large capital cost) prior to emission) is avoided. Thus, in the present process the by-products of each reaction and/or treatment step may be recycled and reused without emission into the environment. The result of this is that the present process is a closed or near-closed loop system which does not require large amounts of virgin bulk reagents. Solid by-products produced (e.g. silica, trace amounts of heavy metal and the like) may be disposed of relatively easily. This is a highly advantageous feature of the present process since it obviates or mitigates shipment of large quantities of reagents and other materials needed for the process thereby facilitating commercial implementation of the process in remote locations.
The present process does not require the use of capital cost intensive scrubbers and other capital cost intensive by-product treatment technologies. Thus, the present process may be implemented on a commercial scale at relatively low capital cost compared with a commercially viable conventional roasting/smelting plant incorporating scrubbers to dealing with sulfur dioxide emissions.
Further, the ability to implement the present process at relatively low temperatures and substantially ambient pressure serves to enable a reduction in relative overall costs associated with operation of the present process on a commercial scale.
BRIEF DESCRIPTION OF THE DRAWING
Embodiments of the present invention will be described with reference to the accompanying FIGURE which is a schematic of an embodiment of the present process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the accompanying FIGURE, there is illustrated a holding tank A which serves to hold a supply of antimony trisulfide concentrate. Holding tank A is connected to a leach station B via a line 10. Leach station B is connected to a solvent extraction station C via a line 15. Solvent extraction station C is connected to leach station B via a line 85. Solvent extraction station C is connected to a hydrolysis station D via a line 20. Hydrolysis station D is connected to a dewatering/drying station E via a line 25.
A line 30 connects a chlorination station F to leach station B. Solvent extraction station C is connected to chlorination station F via a line 35. A line 40 connects dewatering/drying station E to solvent extraction station C.
A line 45 connects line 40 to an ammonium recovery station G. Ammonium recovery station G is connected to a brine purification station H via a line 50. Brine purification station H is connected to a chloro-alkali electrolysis station I via a line 55.
A line 60 connects chloro-alkali electrolysis station I to chlorination station F. A line 65 connects chloro-alkali electrolysis station I to ammonium recovery station G. A line 80 connects chloro-alkali electrolysis station I to line 40. A line 90 connects line 80 to solvent extraction station C. A line 70 connects line 65 to brine purification station H.
In the context of the illustrated embodiment, the present process can be operated in the following manner.
Antimony trisulfide is metered from holding tank A to leach station B via line 10. Iron (III) chloride is fed from chlorination station F to leach station B via line 30. The operation of chlorination station F will be described in more detail hereinbelow.
While not wishing to be bound by any particular theory or mode of action, it is believed that, in leach station B, antimony trisulfide and iron (III) chloride react overall in the following manner:
6FeCl.sub.3 +Sb.sub.2 S.sub.3 →2SbCl.sub.3 +6FeCl.sub.2 +3S
Thus, during the reaction, iron (III) chloride is reduced to iron (II) chloride. The antimony trichloride and iron (II) chloride generally remain in solution.
Preferably, the iron (III) chloride is used as an aqueous solution. While the source of iron (III) chloride is illustrated as chlorination station F, those of skill in the art will realize that an initial source of iron (III) chloride will be used. Preferably, the initial source of iron (III) chloride is an aqueous solution. Preferably, such an aqueous solution comprises from about 5% to about 15%, more preferably from about 8% to about 13%, most preferably from about 10% to about 12%, by weight iron (III). As is known in the, in order to dissolve these quantities of iron (III) in water, it is generally necessary to acidify the aqueous solution. For reasons which will become apparent hereinbelow, a preferred acid for this purpose is hydrochloric acid. Preferably, the hydrochloric acid has a concentration in the range of from about 0.05 to about 4.0, more preferably from about 0.1 to about 1, most preferably from about 0.1 to about 0.5, percent by weight.
Conveniently, the initial source of iron (III) chloride for use in the present process may be a waste stream from another industrial process. For example, a preferred initial source of iron (III) chloride for use in the present process is an iron containing waste stream from pickle liquor used in conventional steel manufacturing plants.
Preferably, the antimony trisulfide and the iron (III) chloride are contacted in leach station B at a temperature in the range of from about 50° to about 100° C., more preferably from about 60° to about 90° C., most preferably from about 75° to about 85° C.
Preferably, the antimony trisulfide and the iron (III) chloride are contacted in leach station B for a period of from about 10 to about 60 minutes, more preferably from about 25 to about 50 minutes, most preferably from about 30 to about 40 minutes.
To facilitate reaction of the antimony trisulfide and the iron (III) chloride, it is preferred to agitate the two. This can be accomplished using conventional mechanical mixers (e.g. rotary impellers) and the like.
In the present process, it is desirable that the antimony chloride-containing liquid emanating from leach station B via line 15 be substantially free of iron (III) chloride. The reason for this will be explained in more detail hereinbelow.
Thus, in a preferred embodiment, leach station B is divided into at least two stages (not shown). In the first stage, antimony trisulfide is reacted with less than a stoichiometric amount of iron (III) chloride. Preferably, the first stage comprises reacting antimony trisulfide with from about 60% to about 95%, more preferably from about 70% to about 90%, most preferably from about 75% to about 85%, of a stoichiometric amount of iron (III) chloride.
The advantage of this approach is that, in the first stage, since iron (III) chloride is present in a sub-stoichiometric amount, it substantially completely reacts with the antimony trisulfide which is present in excess in the first stage. The resulting reaction mixture comprises antimony trichloride and iron (II) chloride in solution, and unreacted antimony trisulfide and sulfur (a by-product of the reaction--see above) particles in suspension. The unreacted antimony trisulfide and sulfur particles may be separated from the reaction mixture using any conventional physical separation technique. The separated liquid (i.e. containing antimony trichloride and iron (II) chloride in solution) is then fed to solvent extraction station C via line 15.
The unreacted antimony trisulfide and sulfur particles from the first stage of leach station B are preferably then reacted in a second stage of leach station B. Preferably, the second stage of leach station B comprises reacting the antimony trisulfide particles from the first stage of leach station B with at least a substantially stoichiometric, preferably an excess stoichiometric, amount of iron (III) chloride. Thus, the reaction mixture produced in the second stage of leach station B comprises antimony trichloride, iron (II) chloride and iron (III) chloride in solution, and sulfur particles and other insoluble impurities in suspension. The sulfur particles and other insoluble impurities may be separated from the reaction mixture using any conventional physical separation technique and are fed to a waste disposal station (not shown) via a line 33. The separated liquid (i.e. containing antimony trichloride, iron (II) chloride and iron (III) chloride in solution) is then fed to the first stage of leach station B.
Thus, as will be appreciated by those of skill in the art, the product of leach station B is an aqueous liquid comprising antimony trichloride and iron (II) chloride in solution. The aqueous liquid comprising antimony trichloride and iron (II) in solution is fed to solvent extraction station C via line 15. As discussed above, it is preferred that the aqueous liquid fed to solvent extraction station C is the result of reaction of antimony trisulfide with a sub-stoichiometric amount of iron (III) chloride (e.g. from the first stage of leach station B discussed hereinabove).
In solvent extraction station C, the aqueous liquid comprising dissolved antimony trichloride and iron (II) chloride from leach station B is contacted with an organic solvent resulting in extraction of antimony trichloride from the aqueous liquid to the organic solvent. Ideally, the organic solvent for use in solvent extraction station C should be one which acts to complex one of antimony trichloride or iron (II) chloride to the exclusion of the other. In the context of the present process, it has been discovered that an organic solvent comprising tributyl phosphate is particularly well suited for this purpose. Specifically, when contacted with a mixture comprising both antimony trichloride and iron (II) chloride, tributyl phosphate will selectively complex with antimony trichloride.
Preferably, the organic solvent for use in organic solvent extraction station C comprises tributyl phosphate in an amount in the range of from about 20% to about 70%, more preferably from about 20% to about 60%, most preferably from about 20% to about 35%, by volume of the organic solvent. The remainder of the organic solvent may be any organic liquid which is miscible with and does not deleteriously affect the function of the organic solvent in solvent extraction station C. Preferably, the remainder of the organic solvent is kerosene.
To facilitate extraction of the antimony trichloride from the aqueous liquid into the organic solvent, it is preferred to agitate the two. This can be accomplished using conventional mechanical mixers (e.g. a rotary impeller) and the like.
Although not wishing to be bound by any particular theory or mode of action, it is believed that the following overall reaction occurs in solvent extraction station C:
SbCl.sub.3 +n(C.sub.4 H.sub.9).sub.3 PO.sub.4 ⃡SbCl.sub.3.((C.sub.4 H.sub.9 O).sub.3 PO).sub.n
The antimony-organic complex believed to result from the reaction is readily soluble in the organic solvent in solvent extraction station C. The iron (II) chloride is minimally affected by contact with the tributyl phosphate and thus a majority remains in the aqueous solvent.
As described above, it is desirable in the present process to avoid the presence of iron (III) chloride from leach station B in solvent extraction station C. The principal reason for this is that the preferred extraction solvent comprising tributyl phosphate will not differentiate between antimony trichloride and iron (III) chloride. The result of this would defeat the purpose of solvent extraction station C, namely to separate substantially all of the antimony trichloride from the aqueous liquid from leach station B. This potential problem is mitigated or obviated by using the preferred two-stage design of leach station B discussed hereinabove.
Upon completion of extraction, the organic solvent (comprising dissolved antimony trichloride believed to be in the form of the antimony-organic complex referred to hereinabove) and the aqueous liquid are separated using conventional techniques such as phase separation and the like.
While the solvent extraction station C as described is effective for selective extraction of antimony trichloride, in certain cases trace amounts of iron (II) compounds may be concurrently extracted into the organic solvent. In such cases, after separation of the organic solvent from the aqueous liquid in solvent extraction C, it is preferred to scrub the organic solvent with an aqueous solvent which will selectively remove any trace amounts of iron (II) compounds present in the organic solvent. Preferably, the aqueous solvent used to scrub the organic solvent is an aqueous inorganic acid. In the context of the present process, aqueous hydrochloric acid has been found to be particularly useful to scrub the organic solvent and remove any trace amounts of iron (II) compounds which may be present in the organic solvent. Preferably, the aqueous inorganic acid comprises from about 1.0 to about 10.0, more preferably from about 4.0 to about 8.0, percent by weight hydrochloric acid. The use of acid in this manner also advantageously facilitates avoidance of partial hydrolysis of the antimony trichloride to antimony oxychlorides.
Once the organic solvent comprising antimony trichloride has been scrubbed (if necessary), it is desirable to contact the organic solvent with an aqueous solution capable of extracting antimony trichloride from the organic solvent to the aqueous solution. Thus, the purpose of this extraction is to strip the antimony trichloride from the tributyl phosphate-containing organic solvent. It has been discovered that an aqueous solution containing ammonium chloride is particularly well suited for this purpose. Preferably, the aqueous solution used for this purpose comprises ammonium chloride in an amount in the range of from about 125 to about 250 g/L, most preferably from about 200 to about 250 g/L.
Thus, solvent extraction station C preferably comprises separate stages for solvent extraction, scrubbing and stripping. In the solvent extraction stage, the ratio of the organic phase volume to the aqueous phase volume (hereinafter referred to as the O/A ratio) is preferably in the range of from about 1.0 to about 3.0, most preferably from about 1.8 to about 2.2. It is also preferred that the solvent extraction stage comprise from 1 to 4, most preferably 2, sequential tanks. In the scrubbing stage, the O/A ratio is preferably in the range of from about 2.0 to about 20.0, most preferably from about 3.0 to about 8.0. It is also preferred that the scrubbing stage comprise from 2 to 10, most preferably 4, sequential tanks. In the stripping stage, the O/A ratio is preferably in the range of from about 1.0 to about 3.0, most preferably from about 1.8 to about 2.2. It is also preferred that the stripping stage comprise from 4 to 8, most preferably 6, sequential tanks.
Thus, after the stripping operation in solvent extraction station C, an aqueous solution comprising ammonium chloride and substantially pure antimony trichloride is produced. This solution is then fed to hydrolysis station D wherein the antimony trichloride is hydrolyzed to produce antimony trioxide.
In a preferred embodiment of the present process, prior to hydrolysis station D, the oxidation-reduction potential (hereinafter referred to as ORP) of the aqueous solution comprising ammonium chloride (i.e. the solution from the stripping stage of solvent extraction station C) is determined and adjusted, if necessary, by addition any suitable oxidizing agent such as hydrogen peroxide, sodium hypochlorite or the like, such that the ORP is in the range of from about 5 to about 100 ORP, most preferably from about 20 to about 50 mV. Determination of ORP can be achieved using a conventional ORP probe and is within the scope of a person skilled in the art. It has been determined that control of the ORP in this manner improves the colour (i.e. the whiteness) of the antimony trioxide eventually produced.
In hydrolysis station D, it is preferred to contact the aqueous solution comprising antimony trichloride with an aqueous base to produce particulate antimony trioxide. The base should be one which is capable of converting the antimony trichloride to antimony trioxide--see, for example, Canadian patent 1,014,332 (Shafer), the contents of which are hereby incorporated by reference.
Preferably, the base is selected from the group comprising alkali metal bases (e.g. alkali metal chlorides and alkali metal hydroxides), alkaline earth metal bases (e.g. alkaline earth metal chlorides and alkaline earth metal hydroxides) and ammonium bases (e.g. ammonium hydroxide).
The most preferred base for use in hydrolysis station D is ammonium hydroxide. One of the significant advantages of using ammonium hydroxide is that, since it is the conjugate base of the preferred salt (i.e. ammonium chloride) used in the strip operation in solvent extraction station C, ammonium hydroxide may be readily recovered, recycled and reused in the present process. It is especially preferred to use a base comprising ammonium hydroxide at a concentration of from about 8 to about 30, most preferably from about 8 to about 12, percent by weight.
Preferably, the base is used in an amount to maintain the pH of the reaction mixture in the range of from about 7.0 to about 9.0, most preferably from about 8.0 to about 8.5. Maintaining the pH of the reaction mixture in this manner facilitates production of senarmontite crystalline form of antimony trioxide.
Although not wishing to be bound by any particular theory or mode of action, it is believed that, when ammonium hydroxide is used as the base in hydrolysis station D and pH is controlled to facilitate formation of the senarmontite crystalline form of antimony trioxide, ammonium hydroxide reacts overall with antimony trichloride in the following manner:
2SbCl.sub.3 +6NH.sub.4 OH→Sb.sub.2 O.sub.3 +6NH.sub.4 Cl+3H.sub.2 O
When ammonium hydroxide is used in hydrolysis station D, the reaction with antimony trichloride is exothermic. The water in the reaction system should be sufficient to absorb the heat of reaction from hydrolysis. However, in certain cases it may advantageous to cool the vessel in which hydrolysis occurs to maintain the temperature at less than about 40° C., preferably in the range of from about 0° to about 20° C., most preferably in the range of from about 10° to about 15° C.
Preferably, the antimony trichloride and the ammonium hydroxide are contacted in hydrolysis station D for a period of less than about 20 minutes, more preferably from about 5 seconds to about 15 minutes, most preferably from about 5 seconds to about 10 minutes.
Thus, after hydrolysis in hydrolysis station D, an aqueous liquid comprising substantially pure antimony trioxide in suspension is produced. This aqueous liquid containing antimony trioxide in suspension is then fed to dewatering/drying station E via line 25.
In dewatering/drying station E, the aqueous liquid is washed and dewatered using conventional counter-current washing/dewater techniques, preferably in a sequential manner. Thus, in drying station E, the aqueous liquid is initially fed to a conventional liquid/solid separator (not shown) wherein bulk antimony trioxide is separated from the aqueous liquid. The bulk antimony trioxide is then fed to a conventional drier (not shown), wherein drying of the antimony trioxide is effected. The dried antimony trioxide is then fed to a packaging station (not shown) wherein it is bagged or otherwise packaged for shipment to the end user.
As discussed hereinabove, one of the key advantages of the present process is the ability to recycle and reuse many of the reagents. The result of this is that the present process may be regarded as a substantially closed or near-closed loop, requiring little or no virgin reagents. Thus, the present process mitigates or obviates the high costs associated with purchase of virgin reagents for continuous production of antimony trioxide.
Thus, with reference to the accompanying FIGURE, the aqueous hydrochloric acid from the scrubbing operation (i.e. containing trace amounts of iron (II) compounds) of solvent extraction station C may be recycled to leach station B. This facilitates recovery of iron from solvent extraction station C.
A portion of the ammonium chloride produced as a by-product during hydrolysis may be recycled to solvent extraction station C wherein it may be used in the stripping operation discussed hereinabove. The remaining portion of the ammonium chloride may be fed to ammonium recovery station G. In ammonium recovery station G, the ammonium chloride is converted to ammonium hydroxide pursuant to the following overall reaction:
NH.sub.4 Cl+NaOH→NH.sub.4 OH↑+NaCl
The ammonium hydroxide is produced in gaseous form which may be readily absorbed by and dissolved in water to produce an aqueous solution of ammonium hydroxide. The aqueous solution of ammonium hydroxide may be recycled to the hydrolysis station D via line 95 wherein it may be used in the hydrolysis reaction discussed hereinabove. The sodium chloride solution is fed to brine purification station H. In brine purification station H, residual heavy metal impurities are removed from the sodium chloride solution.
The choice, design and operation of equipment for use in ammonium recovery station G and brine purification station H is within the purview of a person skilled in the art.
The concentrated sodium chloride solution produced in brine purification station H is fed to chloro-alkali electrolysis station I. In chloro-alkali electrolysis station I, the concentrated sodium chloride solution is electrolyzed to produce chlorine gas and sodium hydroxide. Hydrochloric acid is also a product of chlorine combination with hydrogen. While not wishing to be bound by any particular theory or mode action, it is believed that the following overall reactions occur in the chloro-alkali system:
2NaCl+2H.sub.2 O→Cl.sub.2 ↑+2NaOH+H.sub.2 ↑H.sub.2 +Cl.sub.2 +Δ→2HCl
A portion or all of the aqueous sodium hydroxide produced in chloro-alkali electrolysis station I is fed via line 65 to ammonium recovery station G wherein the aqueous hydroxide solution is used as described hereinabove to convert ammonium chloride to ammonium hydroxide. The remaining portion of the aqueous sodium hydroxide produced in chloro-alkali electrolysis station I may, if necessary, be fed via line 70 to brine purification station H wherein it may be used to adjust the pH of the concentrated sodium chloride solution eventually fed to chloro-alkali electrolysis station I. The hydrochloric acid produced in chloro-alkali electrolysis station I may be recycled to: line 40 (containing ammonium chloride) via line 80 and/or solvent extraction station C via line 90.
The choice, design and operation of equipment for use in chloro-alkali electrolysis station I is within the purview of a person skilled in the art.
A portion of the chlorine gas produced in chloro-alkali electrolysis station I is fed to chlorination station F via line 60. In chlorination station F, chlorine gas reacted with iron (II) chloride from solvent extraction station C pursuant to the following overall reaction:
2FeCl.sub.2 +Cl.sub.2 →2FeCl.sub.3
Thus, chlorination station F serves to regenerate iron (III) chloride which is then recycled to leach station B via line 30.
The choice, design and operation of equipment for use in chlorination station F is within the purview of a person skilled in the art.
While specific illustrated embodiments have been discussed hereinabove with respect to the attached drawings, it should be clearly understood that variations to and modifications of the illustrated embodiments will become apparent to those of skill in the art which do not depart from and are intended to be included within the spirit and scope of the invention. It is the intent of the Applicant that such variations and modifications are included with in the sprit and scope of the invention. | A process for the production of antimony trioxide comprising the steps of: (i) reacting antimony trisulfide with iron (III) chloride to produce antimony trichloride; and (ii) hydrolyzing antimony trichloride to produce antimony trioxide. In a preferred embodiment, the process is substantially closed or near-closed loop. Antimony trioxide is a known flame retardant for use in plastics, ceramics and the like. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates broadly to a method of deriving a shadow map for real-time shadow generation in computer graphical representation of a scene, a data storage medium and a computer system.
BACKGROUND
[0002] Real-time shadow generation in computer graphics systems is gaining much attention recently due to the growing processing supports by powerful graphic processing units. In many applications, shadows are important because they add further realism to scenes and provide additional depth cues.
[0003] Finding ways on how to calculate shadows started a few decades ago. We note that in most of the techniques there is a trade off between shadow quality and rendering time. Recent approaches are based on the standard shadow map algorithm (SSM). This two-pass algorithm is neat and easy to understand. In the first pass, the scene is rendered from the viewpoint of the light with depth buffer enabled. This buffer is read or stored into an image called shadow map. In the second pass, the scene is rendered from the camera viewpoint incorporating shadow determination for each fragment. A fragment is in shadow if its z-value when transformed into the light's view is greater than its corresponding depth value stored in the shadow map.
[0004] The standard shadow map algorithm is easy to implement and is also fast in its calculation compared to other approaches. Additionally, its operations can be mapped and be executed efficiently in recent graphics hardware. A special texture is used for the shadow map and the shadow determination is performed with projective texture mapping.
[0005] On the other hand, SSM has a number of limitations. The first drawback is a resolution problem. The SSM works well when the light is close to the scene and to the viewpoint of the eye, but produces aliases around shadow boundaries when the light is far away. This is caused by low shadow map resolution in areas where a higher resolution is needed. Besides the practical scenario where only a small amount of texture memory is used to capture shadow map, this problem can arise as the focus region of the eye's frustum contributes a very small fraction to the shadow map—whereas the remaining space in the shadow map that corresponds to those locations invisible to the eye's view is not utilised.
[0006] Another limitation is referred to as polygon offset problem. Due to the image space property, shadow comparisons are performed with finite precision which causes the problem of self-shadowing. This can be addressed by finding a bias (and a slope factor) which is added to the depth values of the shadow map to move the z-values slightly away from the light. We note that some approaches solve the resolution problem at the cost of worsening the polygon offset problem using a non-linear distribution of the depth values.
[0007] Another limitation is referred to as a continuity problem where the shadow map quality changes significantly from frame to frame resulting in the flickering of shadows. This occurs in all modified shadow map approaches such as the bounding box approximation approach (see FIG. 2 ) and the perspective shadow maps. Specifically, for example, perspective shadow maps rely on the convex hull of all objects that can cast shadows. This convex hull and the resulting shadow quality can change suddenly. In one case, this occurs when objects move into or out of the light's frustum in a dynamic environment. In another case, it can be observed when the algorithm virtually moves the position of the eye to avoid, for example, the inverted order of objects due to the perspective projection.
[0008] Hence, it was with a view to balancing the above mentioned limitations that the present invention was conceived and has now been reduced to practice.
SUMMARY
[0009] In accordance with a first aspect of the present invention there is provided a method of real-time shadow generation in computer graphical representation of a scene, the method comprising defining an eye's frustum based on a desired view of the scene; defining a location of a light source illuminating at least a portion of the scene; generating a trapezoid to approximate an area, E, within the eye's frustum in the post-perspective space of the light, L; applying a trapezoidal transformation to objects within the trapezoid into a trapezoidal space for computing a shadow map; and determining whether an object or part thereof is in shadow in the desired view of the scene utilising the computed shadow map.
[0010] Generating the top and base lines I t and 1 b respectively, of the trapezoid to approximate E in L, may comprise
computing a centre line I, which passes through centres of the near and far planes of E; calculating the 2D convex hull of E; calculating I t that is orthogonal to I and touches the boundary of the convex hull of E; calculating I b which is parallel to I t and touches the boundary of the convex hull of E.
[0015] In the case that the centres of the far and near planes of E are substantially coincident, a smallest box bounding the far plane may be defined as the trapezoid.
[0016] Generating the side lines of the trapezoid to approximate E in L may comprise
assigning a distance d from the near plane of the eye's frustum to define a focus region in the desired view of the scene; determining a point p L in L that lies on I at the distance d from the near plane of the eye's frustum; computing the position of a point q on I, wherein q is the centre of a projection to map the base line and the top line of the trapezoid to y=−1 and y=+1 respectively, and to map p L to a point on y=ξ, with ξ between −1 and +1; and constructing two side lines of the trapezoid each passing through q, wherein each sideline touches the 2D convex hull of E on respective sides of I.
[0021] In one embodiment, ξ=−0.6.
[0022] The desired point ξ may be determined based on an iterative process that minimizes wastage.
[0023] The iterative process may be stopped when a local minimum is found.
[0024] The iterative process may be pre-computed and the results stored in a table for direct reference.
[0025] The method may comprise
determining an intersection I, between the light source's frustum and the eye's frustum; computing the centre point e of the vertices of I; defining a centre line I n passing through the position of the eye and e, for generating the trapezoid.
[0029] The method may comprise defining a new focus region which lies between the near and far planes of the eye's frustum that are geometrically pushed closer to tightly bound I.
[0030] The trapezoidal transformation may comprise mapping the four corners of the trapezoid to a unit square that is the shape of a square shadow map, or to a general rectangle that is the shape of a rectangular shadow map.
[0031] The size of the square or general rectangle may change based on a configuration of the light source and the eye.
[0032] The trapezoidal transformation may transform only the x and the y values of a vertex from the post-perspective space of the light to the trapezoidal space, while the z value is maintained at the value in the post-perspective space of the light.
[0033] The method may comprise applying the trapezoidal transformation to obtain the x, y, and w values in the trapezoidal space, x T , y T , and w T , and computing the z value in the trapezoidal space, z T , as
z T = z L · w T w L . ,
where z L and w L , are the z and w values in the post-perspective space of the light, respectively.
[0034] The method may comprise:
in a first pass of shadow map generation,
transforming coordinate values of a fragment from the trapezoidal space back into the post-perspective space L of the light to obtain a first transformed fragment, utilising the plane equation of the first transformed fragment to compute a distance value of the first transformed fragment from the light source in L, z L1 , adding an offset value to z L1 , and store the resulting value as a depth value in the shadow map;
in a second pass of shadow determination,
transforming texture coordinate assigned, through projective texturing, to the fragment from the trapezoidal space back into L, obtaining a second transformed fragment from the transformed texture coordinate, utilising the plane equation of the second transformed fragment to compute a distance value of the second transformed fragment from the light source in L, z L2 , and determine whether the fragment is in shadow based on a comparison of the stored depth value in the shadow map and z L2 .
[0039] The method may comprise
in a first pass of shadow map generation,
during a vertex stage, transforming coordinate values of the vertex into the trapezoidal space, and assigning to the vertex the texture coordinate equal to the vertex's coordinate values in the post-perspective space of the light, and during a fragment stage, replacing the depth of the fragment with the texture coordinate of the fragment, adding to the depth an offset, and store the resulting value as a depth value in the shadow map;
in a second pass of shadow determination,
during the vertex stage, transforming coordinate values of the vertex into the post-perspective space of the eye, and assigning to the vertex two texture coordinates that are first the coordinate values of the vertex in the post-perspective space of the light and second the coordinate values of the vertex in the trapezoidal space, and during the fragment stage, determining shadow of the fragment based on a comparison of the stored depth value in the shadow map, as indexed based on the second texture coordinate of the fragment, with a value based on the first texture coordinate of the fragment.
[0046] The method may comprise:
in a first pass of shadow map generation,
transforming coordinate values of a fragment from the trapezoidal space back into the post-perspective space L of the light to obtain a first transformed fragment, utilising the plane equation of the first transformed fragment to compute a distance value of the first transformed fragment from the light source in L, z L1 , adding an offset value to z L1 , and store the resulting value as a depth value in the shadow map,
in a second pass of shadow determination,
during the vertex stage, transforming coordinate values of the vertex into the post-perspective space of the eye, and assigning to the vertex two texture coordinates that are first the coordinate values of the vertex in the post-perspective space of the light and second the coordinate values of the vertex in the trapezoidal space, and during the fragment stage, determining shadow of the fragment based on a comparison of the stored depth value in the shadow map, as indexed based on the second texture coordinate of the fragment, with a value based on the first texture coordinate of the fragment.
[0052] The method may comprise:
in a first pass of shadow map generation,
during a vertex stage, transforming coordinate values of the vertex into the trapezoidal space, and assigning to the vertex the texture coordinate equal to the vertex's coordinate values in the post-perspective space of the light, and during a fragment stage, replacing the depth of the fragment with the texture coordinate of the fragment, adding to the depth an offset, and store the resulting value as a depth value in the shadow map;
in a second pass of shadow determination,
transforming texture coordinate assigned, through projective texturing, to the fragment from the trapezoidal space back into L, obtaining a second transformed fragment from the transformed texture coordinate, ufilising the plane equation of the second transformed fragment to compute a distance value of the second transformed fragment from the light source in L, z L2 , and determine whether the fragment is in shadow based on a comparison of the stored depth value in the shadow map and z L2 .
[0058] The method may further comprise adding a polygon offset in the determining whether an object or part thereof is in shadow in the desired view of the scene for representation utilising the computed shadow map.
[0059] Two or more light sources may illuminate at least respective portions of the scene, and the method is applied for each light source.
[0060] In accordance with a second aspect of the present invention there is provided a system for real-time shadow generation in computer graphical representation of a scene, the system comprising a processor unit for defining an eye's frustum based on a desired view of the scene; for defining a location of a light source illuminating at least a portion of the scene; for generating a trapezoid to approximate an area, E, within the eye's frustum in the post-perspective space of the light, L, from the light source; for applying a trapezoidal transformation to objects within the trapezoid into a trapezoidal space, for computing a shadow map; and for determining whether an object or part thereof is in shadow in the desired view of the scene utilising the computed shadow map.
[0061] In accordance with a third aspect of the present invention there is provided a data storage medium having stored thereon computer code means for instructing a computer to execute a method of real-time shadow generation in computer graphical representation of a scene, the method comprising defining an eye's frustum based on a desired view of the scene; defining a location of a light source illuminating at least a portion of the scene; generating a trapezoid to approximate an area, E, within the eye's frustum in the post-perspective space of the light, L, from the light source; applying a trapezoidal transformation to objects within the trapezoid into a trapezoidal space for computing a shadow map; and determining whether an object or part thereof is in shadow in the desired view of the scene utilising the computed shadow map.
BRIEF DESCRIPTION OF THE DRAWINGS
[0062] Embodiments of the invention will now be described, by way of example only, and in conjunction with the drawings, in which:
[0063] FIG. 1 illustrates a comparison between the shadows generated in the light's post-perspective space and in the trapezoidal space as described in an example embodiment.
[0064] FIG. 2 illustrates a comparison between the shadows generated in two consecutive frames by a bounding box approximation approach and a trapezoidal approximation approach as described in the example embodiment.
[0065] FIG. 3 illustrates a comparison between the shadow maps generated utilising the bounding box approximation approach and the trapezoidal approximation approach as described in the example embodiment.
[0066] FIG. 4 illustrates the trapezoidal transformation taking place in the trapezoidal approximation approach as described in the example embodiment.
[0067] FIG. 5 illustrates the trapezoidal transformation that maps focus region to within 80% of the shadow map as described in the example embodiment.
[0068] FIG. 6 shows the schematic diagram of the trapezoidal approximation approach as described in the example embodiment.
[0069] FIG. 7 shows a plot of the areas occupied by the focus regions in the shadow map with a constant up vector of the eye while varying the angle between the eye's and the light's line of sight.
[0070] FIG. 8 illustrates the quality of the shadows generated by the trapezoidal approximation approach as described in the example embodiment.
[0071] FIG. 9 is a schematic drawing of a computer system for implementing the method and system according to the example embodiment.
[0072] FIG. 10 illustrates the trapezoidal transformation and the four vertices of the trapezoid mapping the focus region to within 80% of the shadow map as described in the example embodiment.
[0073] FIG. 11 illustrates the step of transforming the centre of the top edge of the trapezoid to the origin during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0074] FIG. 12 illustrates the step of rotating the trapezoid during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0075] FIG. 13 illustrates the step of transforming the intersection of the two side lines containing the two side edges during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0076] FIG. 14 illustrates the step of shearing the trapezoid during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0077] FIG. 15 illustrates the step of scaling the trapezoid during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0078] FIG. 16 illustrates the step of transforming the trapezoid to a rectangle during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0079] FIG. 17 illustrates the step of translating the rectangle along the y-axis during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0080] FIG. 18 illustrates the step of scaling the rectangle during calculation of the trapezoidal transformation matrix as described in the example embodiment.
[0081] FIG. 19 illustrates the final result representative of the trapezoidal transformation matrix as described in the example embodiment.
DETAILED DESCRIPTION
[0082] With reference to FIG. 1 , an example embodiment of the present invention provides a method of calculating three Dimensional (3D) computer graphic shadows utilising trapezoidal shadow maps which are derived from trapezoidal approximations of the eye's frustums as seen from the light's view.
[0083] FIG. 1 ( a ) shows the shadow map 102 of the scene 106 with 225 regularly spaced plant models 104 computed directly from the light's view or also known as the light's post-perspective space. As the light is far away, shadow aliasing appears in the view of the eye as shown in the shadow 108 . FIG. 1 ( b ) shows the shadow map 110 of the scene 114 computed from the light's view after applying trapezoidal transformation to focus on the region (of only 15 plant models 112 ) which is potentially visible to the eye. As a result, a high quality shadow 116 is obtained.
[0084] In addition, with reference to FIG. 2 , the method of the example embodiment resolves shadow flickering caused by the continuity problem where the shadow quality changes drastically from frame to frame. In each of the four pictures, the post-perspective space of the light is on the top left e.g. 222 , the generated shadow map on the top right e.g. 224 , and the shadow of a plant 210 , 212 , 218 and 220 (as in the scene of FIG. 1 ) on the bottom. FIG. 2 ( a ) shows the flickering of shadows (compare shadows 210 , 212 ) from one frame i to the next frame i+1 generated by a standard bounding box approximation approach with the bounding box 204 of the area 202 within the eye's frustum as seen from the post-perspective space of a light source. The shadow quality of shadow 212 is significantly poorer as compared to that of shadow 210 . In contrast, FIG. 2 ( b ) shows a smooth shadow transition compare shadows 218 , 220 from one frame i to the next frame i+1 generated with the use of a trapezoidal approximation approach as described in the example embodiment. There is not much difference in the quality of shadow 218 and shadow 220 . Furthermore, it can again be seen that the quality of e.g. shadow 218 is improved compared to e.g. shadow 210 .
[0085] Without loss of generality, the description assumes that there is a single light in the scene and the eye's frustum is completely within the light's frustum. In other words, there is a single light source that generates shadows. Other situations such as where the vertices of the eye's frustum lie behind or on the plane passing through the centre of the projection of the light and parallel to the near plane of the light will be discussed in the later part of the description.
[0086] A shadow map can be viewed to consist of two portions: one within and the other outside the eye's frustum. It is recognised that only the former is useful in the determination of whether pixels are in shadow. Thus, to increase the shadow map resolution in one way is to minimise the entries occupied by the latter, collectively termed as wastage. FIG. 3 shows an example of the trapezoidal approximation 306 in the example embodiment and a smallest bounding box approximation 308 of the area 302 within the eye's frustum as seen from the light. One way to address the resolution problem is to better utilise the shadow map for the area 302 within the eye's frustum as seen from the light, herein referred to as E. This requires the calculation of an additional normalisation matrix N to transform the post-perspective space 300 of the light to an N-space, in general (where N-space, refers to the trapezoidal space 304 or the bounding box space 310 ) in FIG. 3 . The shadow map is then constructed from the N-space, as opposed to from the post-perspective space 300 . During shadow determination, a pixel is transformed into the N-space, rather than into the post-perspective space of the light, for the depth comparison.
[0087] Intuitively, the closer the approximation is to Area E, 302 the better the resolution of the resulting shadow map. The smallest such area is the convex hull C of area E, 302 . However, it is not clear how to efficiently transform C (which is a polygon of up to six edges) to a shadow map (generally a rectangular shape) while minimising wastage.
[0088] The next natural choice is to use the smallest enclosing bounding box B 308 to approximate C for the purpose. However, a bounding box approximation may not always result in minimum wastage, as can be seen from a comparison of the bounding box space 310 with the trapezoidal space 304 in FIG. 3 .
[0089] In the example embodiment, a trapezoid is recognised to be a suitable shape to approximate area E, 302 . More importantly, its two parallel top and base edges 305 , 307 form a surprisingly powerful mechanism to control the shape and the size of a trapezoid from frame to frame (as will be discussed later). This successfully addresses the continuity problem. Equally important and interesting for the choice of trapezoid in the example embodiment are its two side edges 309 , 311 in addressing another kind of “implicit” wastage not mentioned in the above discussion. Such wastage is the over-sampling of near objects in the shadow map where a lower sampling rate would suffice. The example embodiment has an efficient mechanism to decide on the two side edges 309 , 311 to spread the available resolution to objects within a specified focus region. In comparison, the transformation used in the smallest bounding box B 308 does not have such flexibility in stretching a shape. As a result, the smallest bounding box approach has a deteriorating effect on the shadow map resolution when the depth of view increases.
[0090] As mentioned, in the background section, the continuity problem is a consequence of a significant change in the shadow map quality from one frame to the next, resulting in flickering of shadows. For the smallest bounding box approach, the shadow map quality changes if there is a sudden change in the approximation of the area within the eye's frustum as seen from the light. FIG. 2 ( a ) shows from frame i to frame i+1 that the orientation of the approximation of the area within the eye's frustum as seen from the light 202 , 203 respectively with the smallest bounding box 204 , 205 respectively is changed. As a result, there is a drastic change to the resolution in different parts of the shadow map. In general, the problem can often occur when the eye's frustum as seen from the light transits from one shape to another different shape (where the number of side planes of the eye's frustum as seen from the light visible from the light's view is different). In contrast, in the trapezoidal approach of the example embodiment, FIG. 2 ( b ) shows from frame i to frame i+1 that no drastic change occurs to the resolution in different parts of the shadow map, compare shadows 218 , 220 .
[0091] With reference to FIG. 6 , the example embodiment has an efficient and effective way to control the changes in trapezoids to address the continuity problem.
[0092] The aim is to construct a trapezoid to approximate the area E, 602 , within the eyes frustum as seen from the light with the constraint that each such consecutive approximation results in a smooth transition of the shadow map resolution. The strategy adopted in the example embodiment is to rely on a smooth transition in the shape and size of trapezoid to result in a smooth transition of the shadow map resolution. To begin with, the example embodiment makes computations to obtain the base and top line. From these, the base and top edge of the trapezoid are defined when the two side lines are computed.
[0093] The following describes the computation to obtain the base and top line of the trapezoidal boundary on E, 602 .
[0094] The computation is done to find two parallel lines in the post-perspective space of the light L, 600 , to contain the base and the top edges of the required trapezoid. The aim is to choose the parallel lines such that there is a smooth transition when the eye moves (relative to the light) from frame to frame.
[0000] First, the eye's frustum is transformed into the post-perspective space L 600 of the light to obtain E, 602 .
[0000] Next, the centre line I 604 , which passes through the centres of the near plane 622 and the far plane 624 of E 602 is computed.
[0000] Next, the 2D convex hull of E 602 (with at most six vertices on its boundary) is calculated.
[0095] Next, the top line I t 608 that is orthogonal to I 604 and touches the boundary of the convex hull of E 602 is calculated. The top line I t 608 intersects I 604 at a point closer to the centre of the near plane 622 than that of the far plane 624 of E 602 .
[0000] Then, the base line I b 606 which is parallel to (and different from) the top line I t 608 (i.e., orthogonal to I too) and touches the boundary of the convex hull of E 602 is calculated.
[0096] The above algorithm is such that the centre line I 604 governs the choices of I t 608 and I b 606 , with the exception for the case when the centres of the far and near planes (almost) are coincident. In the example embodiment, the algorithm handles that separately to result in the smallest box bounding the far plane 624 as the desired trapezoid. The next two paragraphs explain the rationale of the above algorithm to address the continuity problem.
[0097] Imagine E, 602 , the eye's frustum is drawn within a sphere with the centre of the sphere at the eye's position and the radius equal to the distance from the eye to each corner of the far plane 624 . Suppose the eye's location does not change. Pitching and heading of the eye from one frame to the next can be encoded as a point (which is the intersection of I 604 with the sphere) on the sphere to another nearby point, while rolling of the eye does not change the encoded point but results in a rotation of eye's frustum along I 604 . More importantly, with a smooth eye motion from frame to frame, the four corners of the far plane 624 of the eye's frustum lying on the sphere also have a smooth transition on the sphere. As the positions of I 604 and the mentioned four corners uniquely determine I b 606 , it also transits smoothly from frame to frame. Similarly, I t 608 transits smoothly from frame to frame, too.
[0098] Next, suppose the eye's location does change relative to the light from one frame to the next but maintains its orientation. In this case, it is only a matter of scaling E, 602 , and the I b 606 and I t 608 computed are parallel to the previous ones. In other words, both I b 606 and I t 608 again transit smoothly from frame to frame under a smooth translation of the eye's frustum.
[0099] Before describing the computation of the side lines, we first analyse the effect of transforming a given trapezoid in FIG. 5 ( a ) by its N T to a trapezoidal space. Note that N T has the effect of stretching the top edge into a unit length. In this case, the top edge is relatively short compared to the base edge, and therefore the stretching results in pushing all the shown triangles towards the bottom of the unit square as in FIG. 5 ( b ). This means that the region near to the top edge bounded by I t ( 608 in FIG. 6 ) (i.e., close to the near plane ( 622 in FIG. 6 )) eventually occupies a major part of the shadow map. This results in an over-sampling in the shadow map for objects very near to the eye while sacrificing resolution of the other objects (such as the second triangle 502 to the fourth triangle 504 from the top in FIG. 5 ( b )). This is the kind of wastage due to over-sampling as mentioned above.
[0100] For the trapezoid 510 in FIG. 5 ( a ), its corresponding trapezoidal space 508 is shown in FIG. 5 ( b ). In the case of FIG. 5 ( b ), we obtain an over-sampling for a small region of E 506 . In the case of FIG. 5 ( c ), for a different trapezoid computed with the 80% rule (having the same top and base lines), its trapezoidal transformation maps the focus region 512 (the upper part of the trapezoid) to within the first 80% in the shadow map.
[0101] Conversely, a small part of the shadow map is occupied by near objects when a “fat” trapezoid (having top and base edges of almost equal lengths) is transformed by its trapezoidal transformation. As the approach adopted by the example embodiment aims to achieve effective use of available shadow map memory by “important” objects in the eye's frustum, the algorithm to compute the side lines and thereafter compute the required trapezoid is as follows.
[0102] Next, the computation of the side lines, which will form the side edges of the trapezoidal boundary on E, 602 , will be described.
[0103] With reference to FIG. 6 , assume the eye is more interested in objects and their shadows within the distance δ from the near plane 622 . That is, the region of focus, or simply the focus region, of the eye is the eye's frustum truncated at δ distance from the near plane 622 . Let p be a point of δ distance away from the near plane 622 with its corresponding point p L 618 , lying on I, 604 , in L, 600 . Let the distance of p L , 618 , from the top line be δ′, 614 . The example embodiment constructs a trapezoid to contain E, 602 , so that N T maps p L , 618 , to some point on the line of 80% or what is referred in the example embodiment as the 80% line in the trapezoidal space (see FIG. 5 ( c )). Such an approach is herein referred to as the 80% rule.
[0104] To do this, a perspective projection problem is formulated to compute the position of a point q, 620 , on I, 604 , with q, 620 , as the centre of projection to map p L , 618 , to a point on the 80% line y=ξ 610 (i.e. ξ=−0.6), and the base line 606 and the top line 608 to y=−1 and y=+1, respectively. Let λ, 616 , be the distance between the base and the top line. Then, the distance of q, 620 , from the top line, denoted as η, 612 , is computed through the following 1D homogenous perspective projection:
( - ( λ + 2 η ) λ 2 ( λ + η ) η λ 1 0 ) · ( δ ′ + η 1 ) = ( ξ ~ ω ) , and ξ = ξ ~ ω .
So , η = λ δ ′ + λ δ ′ ξ λ - 2 δ ′ - λ ξ .
Next, two lines passing through q, 620 , and touching the convex hull of E, 602 , are constructed to be the side lines containing the side edges of the required trapezoidal boundary.
[0105] For some situations (such as the eye's frustum as seen in the post-perspective space of the light is a dueling frusta case), the 80% rule may result in a significant wastage of shadow map memory. Hence, in the example embodiment, the above algorithm is modified to an iterative process. Suppose the shadow map is a map with x horizontal lines of entries. (Examples of values of x in some applications are 512 , 1024 or 2048 .) In the first iteration, p L 618 , is mapped to the 80% line (or 0.8x), and in each subsequent iteration, p L 618 , is mapped to an entry one line before that of the last iteration to compute q, 620 . With each computed q, 620 , a corresponding trapezoid and its trapezoidal transformation N T are computed as before. From all the iterations, the trapezoid, with its N T that transforms the focus region to cover the largest area (though other metrics are possible) in the shadow map, is adopted. In another embodiment, the iterations can stop once the value of x can be located where the focus region covers a local maximum largest area (or other corresponding metrics) in the shadow map. In other words, the iteration can stop once there is a change from a good coverage to a bad coverage, and use the good coverage to be the value of x. The above computation is not expensive as it involves simple arithmetic and only a small number of iterations. In fact, for a given up vector of the eye and a given angle between the eye's and the light's line of sight, the best ξ, 610 , to where p L , 618 , is mapped is independent of the scene and can thus be pre-computed. Therefore, all these best ξ, 610 , (and thus η, 612 ) can be stored in a table with the parameter of the angle between the eye's and the light's line of sight, for each possible up vector of the eye. Thus, in another embodiment, a simple table lookup can also replace the above iterative process.
[0106] FIG. 7 shows a plot 700 of the areas occupied by the focus regions in the shadow map with a constant up vector of the eye while varying the angle between the eye's and the light's line of sight. The focus regions occupy small areas for the dueling frusta case, but large area when, for example, one side face of E is visible in the light's view.
[0107] To understand the 80% rule, the plot 700 of the total area covered by the focus region in the shadow map is generated by varying the angle (represented as a data point on the xy-plane) between the eye's and the light's line of sight while keeping the up vector constant. Experiments were done with a series of the same kind of plots with different up vectors. It was observed that consecutive plots of slightly different up vectors are surfaces of very close values. These plots indicate that there is a smooth transition on the area occupied by the focus region. This is a strong indication that the approach adopted by the example embodiment addresses the continuity problem well. Therefore, the 80% rule utilised in the example embodiment is effective. In another embodiment, one can adjust this percentage according to the need of the application.
[0108] The above discussion assumes that the eye's frustum lies completely within the lights frustum, such as in an outdoor scene where the sun is the main light source. If this is not the case, one adaptation is to enlarge the light's view to include the eye's frustum. This is not an effective use of the shadow map. Also, this can be delicate to handle and may not always be feasible. There are also situations where the vertices of the eye's frustum lie behind or on the plane passing through the centre of projection of the light and parallel to the near plane of the light. Such vertices have inverted order or are mapped to infinity in L ( 600 in FIG. 6 ). The next two paragraphs discuss a simple extension which avoids such situations.
[0109] Specifically, it suffices to only transform the portion of the eye's frustum that is inside the light's frustum to L ( 600 in FIG. 6 ). The remaining portion, which is not inside the light's frustum, is clearly not illuminated and hence cannot have shadows. Therefore, in the example embodiment, only the intersection I between the light's frustum and the eye's frustum (with no more than 16 intersections as its vertices) are processed. This conveniently avoids the above problem due to the perspective transformation.
[0110] The line I ( 604 in FIG. 6 ) passing through the centres of near and the far plane of the eye's frustum may no longer be the centre line for the computation of the base and top line. One approach is to compute the centre point e of the vertices of I, and use the line passing through the position of the eye and e to be the new centre line I n for the computation. A new focus region has to be defined, because the focus region may not be completely within I. One approach is to geometrically push the near plane ( 622 in FIG. 6 ) and far plane ( 624 in FIG. 6 ) of the eye (closer to each other) to tightly bound I in the world space to obtain f′ as the distance between those planes. Let f be the distance between the original far and near planes of the eye in the world space. Then, in one embodiment, the new focus region lies within the new near plane and its parallel plane, where the distance between the planes is (δf′/f. Note that δ is the distance originally chosen to set the focus region.
[0111] With the above, the approach adopted in an example embodiment is now suited for a wider range of applications: near to far lights, and both indoor and outdoor scenes. FIGS. 8 ( a ) and ( b ) shows the displays of such cases with two lights illuminating a fantasy character. FIG. 8 ( a ) shows the character 806 lit by one nearby light 802 and two nearby lights 804 while viewed from outside the lights' frusta. FIG. 8 ( b ) shows the character 808 lit by a close light (left shadow 810 ) and a far light (right shadow 812 ) rendered by the trapezoidal approximation approach adopted by the example embodiment. From FIG. 8 , it can be observed that the approach adopted in the example embodiment can achieve high shadow quality for the close light situation as well as for the transition to the far light situation, which is unfavourable to the standard shadow map.
[0112] The following description formalises the use of trapezoidal approximation in the approach adopted in the example embodiment.
[0113] Refer to FIG. 3 . Consider a vertex v in the object space. Then, that vertex in the post-perspective space of the light L, 300 is v L =P L ·C L ·W·v where P L and C L are the projection and camera matrices of the light and W is the world matrix of the vertex. The eight corner vertices of E, 302 , in L, 300 , are obtained from the corner vertices of E, 302 in the object space multiplied by P L ·C L ·C E −1 where C E −1 is the inverse camera matrix of the eye. As illustrated in FIG. 4 , E, is treated as a flattened two Dimensional (2D) object on the front face 400 of the light's unit cube 404 . We use a trapezoid T 402 , to approximate (and contain) E treated as the 2D object. A normalisation matrix N T is constructed such that the four corners of T, 402 , are mapped to the unit square 401 or a rectangle. We call v T =N T ·v L a vertex in the trapezoidal space, N T a trapezoidal transformation matrix, and the shadow map derived from the trapezoidal space a trapezoidal shadow map.
[0114] The following describes the calculation of the trapezoidal transformation matrix N T in the example embodiment to map the four corners of T to a unit square. Analogously, one can calculate N T to map the four corners of T to a rectangle.
[0115] With reference to FIG. 10 , the aim is to calculate a transformation N T (4×4 matrix) which maps the four corners of the trapezoid 1000 , t 0 , t 1 , t 2 , and t 3 to the front side of the unit cube 1002 , i.e. to calculate N T with the following constraints:
( - 1 - 1 1 1 ) = N T · t 0 , ( + 1 - 1 1 1 ) = N T · t 1 , ( + 1 + 1 1 1 ) = N T · t 2 , and
( - 1 + 1 1 1 ) = N T · t 3
[0116] There are a few ways to achieve this. A general approach is to calculate using quadrilateral to quad mapping. Another way is to apply rotation, translation, shearing, scaling, and normalisation operations to the trapezoid to map it to the front side of the unit cube. The following illustrates a way to compute N T from a series of 4×4 matrices T 1 , R, T 2 , H, S 1 , N 1 T 3 and S 2 . In the following discussion, the vectors u=(x u , y u , z u , w u ) and v=(x v , y v , z v , w v ) hold intermediate results.
[0117] As a first step, with reference to FIG. 11 , T 1 transforms the centre 1100 of the top edge 1102 to the origin:
u = t 2 + t 3 2 , and T 1 = ( 1 0 0 - x u 0 1 0 - y u 0 0 1 0 0 0 0 1 ) .
[0118] Then, with reference to FIG. 12 , the trapezoid T 1200 is rotated by applying R around the origin in such a way that the top edge 1202 is collinear with the x-axis:
u = t 2 - t 3 t 2 - t 3 , and R = ( x u y u 0 0 y u - x u 0 0 0 0 1 0 0 0 0 1 ) .
[0119] Next, with reference to FIG. 13 , the intersection i of the two side lines 1300 , 1302 containing the two side edges (t 0 , t 3 ) and (t 1 , t 2 ) is transformed, by applying T 2 , to the origin:
u = R · T 1 · i , and T 2 = ( 1 0 0 - x u 0 1 0 - y u 0 0 1 0 0 0 0 1 ) .
[0120] As a next step, with reference to FIG. 14 , the trapezoid has to be sheared with H, so that it is symmetrical to the y-axis, i.e. that the line passing through the centre of the bottom edge 1402 and centre of the top edge 1404 is collinear with the y-axis:
u = T 2 · R · T 1 · ( t 2 + t 3 ) 2 , and H = ( 1 - x u / y u 0 0 0 1 0 0 0 0 1 0 0 0 0 1 ) .
[0121] Next, with reference to FIG. 15 , the trapezoid is scaled by applying S 1 , so that the angle between the two side lines 1500 , 1502 containing the two side edges (t 0 , t 3 ) and (t 1 , t 2 ) is 90 degrees, and so that the distance between the top edge 1504 and the x-axis is 1:
u = H · T 2 · R · T 1 · t 2 , and S 1 = ( 1 / x u 0 0 0 0 1 / y u 0 0 0 0 1 0 0 0 0 1 ) .
[0122] Next, with reference to FIG. 16 , the following transformation N transforms the trapezoid to a rectangle 1600 :
N = ( 1 0 0 0 0 1 0 1 0 0 1 0 0 1 0 0 ) .
[0123] Then, with reference to FIG. 17 , the rectangle 1700 is translated along the y-axis until its centre is coincident with the origin. This is done by applying T 3 . After this transformation the rectangle 1700 is symmetrical to the x-axis as well:
u = N · S 1 · H · T 2 · R · T 1 · t 0 ,
v = N · S 1 · H · T 2 · R · T 1 · t 2 , and
T 3 = ( 1 0 0 0 0 1 0 - ( y u / w u + y v / w v ) 2 0 0 1 0 0 0 0 1 ) .
[0124] Then, with reference to FIG. 18 , the rectangle 1800 has to be scaled with S 2 along the y-axis so that it covers the front side of the unit cube 1900 , as shown in FIG. 19 :
u = T 3 · N · S 1 · H · T 2 · R · T 1 · t 0 , and S 2 = ( 1 0 0 0 0 - w u / y u 0 0 0 0 1 0 0 0 0 1 ) .
[0125] Thus, the trapezoidal transformation N T can be computed as follows:
N T =S 2 ·T 3 ·N·S 1 ·H·T 2 ·R·T 1 .
[0126] Returning to FIG. 4 , in the example embodiment, the intent of N T is to transform only the x and y values of those vertices of objects. This transformation, however, also affects the z value of each vertex depending on its x and y values. Thus, a single offset for all vertices (as in the standard shadow map approach) may not be adequate to remedy surface acne effects.
[0127] FIG. 4 shows the trapezoidal approximation 402 of the eye's frustum within the light's frustum in the post-perspective space of the light. FIG. 4 also shows the trapezoidal approximation under the trapezoidal transformation described above resulting in a unit square 401 (or rectangle) for the front view 405 but a trapezoid on the side view 409 . This worsens the polygon offset problem. FIG. 4 also shows an approach adopted by the example embodiment to maintain a unit square 407 for the side view 408 under the trapezoidal transformation.
[0128] The trapezoidal transformation incorporates a two-dimensional projection. An important property of this transformation is that the z T of the vertex in trapezoidal space depends on the w T . In actual fact, the distribution of the z-values is changing over the trapezoidal shadow map so that a constant polygon offset as in the standard shadow map approach may not be adequate. The problem is that the specified polygon offset might be too high for pixels containing object near to the eye or might be too low for pixels containing object further away. If the polygon offset is too high it can happen that shadows are disappearing; on the other hand, if it is too low surface acne might be introduced.
[0129] By maintaining the depth value in the post-perspective space of the light in the example embodiment, a constant polygon offset may be specified similar to the technique used in the standard shadow map approach to combat the polygon offset problem. The distribution remains uniform, as can be seen from the unit square 407 from the side view 408 in FIG. 4 .
[0130] In one embodiment, to achieve this only the x, y and w values of each vertex are transformed by N T to the trapezoidal space ( 304 in FIG. 3 ), while maintaining the z value in the post-perspective space L ( 300 in FIG. 3 ) of the light. In a simple form, the formula to transform a vertex to the trapezoidal space ( 304 in FIG. 3 ) is now done as in v T =N T v L to get its x T , y T and w T values, and then compute the z T value from the z and w values of v L , i.e. z L and w L , as:
z T = z L · w T w L .
[0131] The above calculation can be implemented with a vertex program to compute the required z T during the first pass of shadow map generation, and another vertex program to compute the corresponding z T in L ( 300 in FIG. 3 ) for each vertex during the second pass of shadow determination. This embodiment is easy to implement and practically workable. However, such an approach is only an approximation to the actual z values. When the eye or light frustums contain no particularly large triangles, such incorrect z value at each point of a triangle was found not to matter, as the error is small and thus negligible once it is adjusted with a relatively large polygon offset.
[0132] To improve on the above embodiment, other embodiments may utilise approaches based on ray casting, and/or based on multiple texture coordinates. Note that each approach has the usual two passes of the shadow map generation and the shadow determination. One can combine these approaches into four different combinations of methods to address the problem.
[0133] In the ray casting approach, the fragment stage is used to compute the correct z value for each fragment in L ( 300 in FIG. 3 ). In the first pass (shadow map generation), N T −1 and the inverse viewport matrix to transform the x and y values of a fragment from the trapezoidal space back to L ( 300 in FIG. 3 ) are used. After that, a plane equation π in L ( 300 in FIG. 3 ) of the fragment is used to compute the z value. This value is added with an offset and then stored into the shadow map. Then, in the second pass (shadow determination), N T −1 is applied to the x T , y T and w T values of the texture coordinate assigned to the fragment (through projective texturing) to obtain x L , y L and w L . With these values, the z value of the fragment in L ( 300 in FIG. 3 ) is computed from π. This z value is to compare with the depth value stored in the (x T /w T , y T /w T )-entry of the shadow map to determine whether the fragment is in shadow.
[0134] In the multiple texture coordinates approach, at the first pass (shadow map generation), the vertex stage transforms each vertex v to v T =(x T , y T , z T , w T ) and assigns v L =(x L , y L , z L , w L ) as its texture coordinate. The texture coordinates over a triangle are obtained by linearly interpolating the v L /w T values of the vertices of the triangle. Next, the fragment stage replaces the depth of the fragment with z L /w L and adds to it an offset. In effect, the z value of the vertex in the trapezoidal space is set as z l with the necessary polygon offset. In the second pass (shadow determination), the vertex stage transforms each vertex to the post-perspective space of the eye as the output vertex. It also computes, for the vertex, two texture coordinates v L =(x L , y L , z L , w L ) and v T =(x T , y T , z T , w T ). Then, the fragment stage processes each fragment to determine shadow by comparing z L /w L to the value in the shadow map indexed by (x T /w T , y T /w T ).
[0135] Annexure A shows vertex and fragment program codes for implementing the trapezoidal transformation in an example embodiment. The approach adopted is the multiple texture coordinates approach described above. Only the shadow map generation step is shown, i.e. the first pass of the algorithm, because the second pass of the algorithm works in a similar way. The same functionality as in Annexure A can be achieved with, for example, other version of vertex and fragment programs or Cg or other computer graphic programs.
[0136] Note that for the sake of clarity, the calculation of a constant polygon offset, which is added to the final depth value is omitted in Annexure A.
[0137] Annexure B shows a display routine for use in an implementation of the described algorithm in an example embodiment.
[0138] The example embodiment may be implemented using GNU C++ and OpenGL under Linux environment on an Intel Pentium 4 1.8 GHz CPU with a nVidia GeForce FX5900 ultra graphics controller. ARB vertex/fragment programs or Cg programs may be used to address the polygon offset problem. The shadow maps may be rendered into a pbuffer or general texture memory. The example embodiment uses various geometric yet simple operations such as convex hulls, line operations etc. in 2D, thus making robustness issues easy to handle.
[0139] Embodiments of the present invention may provide the following advantages.
[0140] Shadow map resolution is improved by approximating the eye's frustum seen by the light with a trapezoid and warping the trapezoid onto a shadow map. This increases the number of samples for areas closer to the eye and therefore results in higher shadow quality.
[0141] The trapezoid is calculated such that a smooth change in shadow map resolution is achieved. The calculation is not computationally expensive as the trapezoid is only calculated based on the eight vertices of the eye's frustum rather than on the whole scene which eliminates the continuity problem occurring in all prior art.
[0142] Furthermore, the trapezoidal approximation is a constant operation and the algorithm scales well. No doubt the warp contains a perspective transformation, where polygon offset becomes an issue. However, this problem can be resolved by one of the three approaches discussed in the example embodiment where utilisation of the vertex/fragment programs or Cg programs on modern graphics hardware is involved.
[0143] It is appreciated that a person skilled in the art can easily apply the present invention utilising multiple light sources with a shadow map for each light source.
[0144] The method and system of the example embodiment can be implemented on a computer system 900 , schematically shown in FIG. 9 . It may be implemented as software, such as a computer program being executed within the computer system (which can be a palmtop, mobile phone, desktop computer, laptop or the like) 900 , and instructing the computer system 900 to conduct the method of the example embodiment.
[0145] The computer system 900 comprises a computer module 902 , input modules such as a keyboard 904 and mouse 906 and a plurality of output devices such as a display 908 , and printer 910 .
[0146] The computer module 902 is connected to a computer network 912 via a suitable transceiver device 914 , to enable access to e.g. the Internet or other network systems such as Local Area Network (LAN) or Wide Area Network (WAN).
[0147] The computer module 902 in the example includes a processor 918 , a Random Access Memory (RAM) 920 and a Read Only Memory (ROM) 922 . The computer module 902 also includes a number of Input/Output (I/O) interfaces, for example I/O interface 924 to the display 908 (or where the display is located at a remote location), and I/O interface 926 to the keyboard 904 .
[0148] The components of the computer module 902 typically communicate via an interconnected bus 928 and in a manner known to the person skilled in the relevant art.
[0149] The application program is typically supplied to the user of the computer system 900 encoded on a data storage medium such as a CD-ROM or floppy disk and read utilising a corresponding data storage medium drive of a data storage device 930 . The application program is read and controlled in its execution by the processor 918 . Intermediate storage of program data maybe accomplished using RAM 920 .
[0150] In the foregoing manner, a method for generating shadows utilising trapezoidal shadow maps is disclosed. Only several embodiments are described. However, it will be apparent to one skilled in the art in view of this disclosure that numerous changes and/or modifications may be made without departing from the scope of the invention. | A method of real-time shadow generation in computer graphical representation of a scene, the method comprising defining an eye's frustum based on a desired view of the scene; defining a location of a light source illuminating at least a portion of the scene; generating a trapezoid to approximate an area, E, within the eye's frustum in the post-perspective space of the light, L; applying a trapezoidal transformation to objects within the trapezoid into a trapezoidal space for computing a shadow map; and determining whether an object or part thereof is in shadow in the desired view of the scene utilising the computed shadow map. | 6 |
FIELD OF THE INVENTION
[0001] The present invention generally relates to antennas and, more specifically, to the forming of a high-frequency inductive antenna.
[0002] The invention more specifically applies to antennas intended for radio frequency transmissions of several MHz in a moist environment, for example, for contactless chip card, RFID tag, or electromagnetic transponder transmission systems.
DISCUSSION OF THE RELATED ART
[0003] FIG. 1 very schematically shows an example of a radio frequency transmission system of the type to which the present invention applies as an example.
[0004] Such a system comprises a reader or base station 1 generating an electromagnetic field capable of being detected by one or several transponders 2 located in its field. Such transponders 2 for example are an electronic tag 2 ′ placed on an object for identification purposes or more generally any electromagnetic transponder (symbolized by a block 2 in FIG. 1 ).
[0005] On the side of reader 1 , a resonant inductive antenna is generally symbolized by a series resonant circuit formed of a resistor r, of a capacitor C 1 , and of an inductive element L 1 or antenna. This circuit is excited by a high-frequency generator (HF) controlled (connection 14 ) by other circuits not shown of base station 1 . A high-frequency carrier is generally modulated (in amplitude and/or in phase) to transmit data to the transponder.
[0006] On the side of transponder 2 , a resonant circuit, generally parallel, comprises an inductive element or antenna L 2 in parallel with a capacitor C 2 and with a load R standing for electronic circuits 22 of transponder 2 . This resonant circuit detects the flow of the high-frequency magnetic field generated by the base station when it is submitted to this field. In the case of an electronic tag 2 ′, inductive element L 2 is formed of a conductive winding connected to an electronic chip 22 . The chip generally encloses capacitor C 2 .
[0007] The symbolic representation in the form of a series resonant circuit on the base station side and of a parallel resonant circuit on the transponder side is usual even if, in practice, one may find series resonant circuits on the transponder side and parallel resonant circuits on the base station side. On the base station side, one may also find a resonant LC structure where the capacitance is split into a parallel portion and a series portion. This enables to add an impedance variation function, for example, to match the impedance with the generator.
[0008] Transponders generally have no autonomous power supply and recover the power necessary to their operation from the magnetic field generated by base station 1 . They transmit data to the station by modifying the load (R) applied to their resonant circuit to modulate the current flowing in their inductive antenna L 2 and resulting from the electromagnetic force induced by the magnetic field of the base station.
[0009] The resonant circuits of the reader and of the transponder are generally tuned to a same resonance frequency ω (L 1 .C 1 .ω 2 =L 2 .C 2 .ω 2 =1). When the transponder is placed in an environment such as air, the electric permittivity of the medium surrounding the transponder is practically that of vacuum (∈ 0 =8.854.10 Farad per meter, or relative permittivity ∈ r =1). The characteristics of the resonant circuit of the transponder (frequency tuning, quality factor) are stable and at their nominal values. However, this is not true in soil (or in any other moist environment) where the variable quantity of water causes a high variability of the electric permittivity of the environment surrounding the transponder, up to very high values. Water has a very high relative electric permittivity ∈ r , of approximately 80. If the resonant circuit of the transponder is not sufficiently protected by an envelope of a material of stable low electric permittivity, the characteristics of the resonant circuit of the transponder will be strongly altered. If the electric permittivity of the protection envelope that may possibly be used is not low, the characteristics of the resonance circuit in the presence of this envelope may be adjusted, provided for this permittivity to be stable.
[0010] FIG. 2 very schematically shows an example of a system of transmission in a moist environment. This system is meant to detect pipes 3 buried in soil S. A base station forming a detector is placed close to surface 55 of soil S. Such a detector emits a radio frequency magnetic field capable of being detected by transponders 2 associated with pipes 3 buried in the soil. Such a system is generally used to detect the presence of ducts in civil engineering works.
[0011] A problem in this type of application is that the soil forms a moist environment capable of varying from a dry soil to a water-saturated soil. Electric permittivity ∈ r (capable of reaching several tens) is then no longer of the same order of magnitude as in air (∈ r =1). As a result, stray capacitances formed between different portions of the inductive circuit (L 2 ) of the transponder antenna are strongly increased, which adds dielectric losses to the resonator. The resonant circuit of the transponder is then no longer tuned and its quality factor is negatively altered, which adversely affects the transmission (remote-supply and communication).
[0012] Current solutions comprise coating the resonant circuit of the transponder with an insulating material (permittivity ∈ r on the order of 1 or ranging up to several units (<5)) which is thick enough for the moist environment to be sufficiently distant and to no longer interfere with the characteristics of the transponder resonator. It is also possible to adjust the resonator characteristics in the presence of the protection material. Although the necessary thickness (in practice, a few millimeters) may seem low, it considerably increases the pipe cost. For other applications, the thinness of the transponder used as a tag may also be a constraint which makes a thickness increase undesirable.
[0013] In particular, in order to locate the path of a duct, tags should be present at small intervals ranging from less than one meter to a few meters.
[0014] Further, it is not desirable for ducts to have large outgrowths (package integrating the transponder, for example).
[0015] On the internal side, even if the pipe is intended to convey liquid, the tube thickness is generally sufficient for the resonator characteristics not to be disturbed.
[0016] FIG. 3 is a perspective view, partially in cross-section, of an example of a known technique for making an electronic tag usable in a moist environment having a moisture content ranging from dry to water-saturated.
[0017] A tag 2 comprising an electronic chip 22 and a planar antenna L 2 is placed on the external surface of pipe 3 . The tag is supported by an insulating sheet, which is flexible so that it can be wrapped around the pipe. Then, the assembly is covered with a flexible insulating layer 35 , for example, rectangular. Even with materials of very low permittivity (equal to or slightly greater than one in relative value), the added thickness remains greater than several millimeters.
[0018] It could be envisaged to embed the tags in the pipe thickness on manufacturing. However, this makes the pipe manufacturing more complex, and thus more expensive. The insertion of an object in the thickness may impose strong manufacturing constraints to maintain/save the mechanical resistance of the pipe.
[0019] There thus is a need for an inductive antenna adapted to moist environments.
[0020] Document WO 2008/083719 describes a small antenna formed of a first circular track interrupted at one point and surrounded with a second track interrupted in two diametrically opposed positions. The first and second tracks do not each form a winding, in the sense of a geometrical figure equivalent to a winding of at least two conductive track turns.
[0021] Document US 2003/080918 describes a wireless communication device and provides associating pressure and temperature sensors with this device.
[0022] Document WO 2007/084510 describes various forms of RFID antennas, including a circular ring antenna formed of discontinuous non-interconnected sections.
[0023] Article “On the resonances and polarizabilities of split ring resonators” by Garcia et al., published in the Journal of Applied Physics, American Institute of Physics, August 2005 (vol. 98, n° 3, pages 033103-1 to 9, describes different forms of resonant circuits formed of pairs of tracks.
[0024] Document JP 2004-336198 describes a loop antenna of several turns with no electric discontinuity.
SUMMARY
[0025] An object of an embodiment of the present invention is to provide an inductive antenna which overcomes all or part of the disadvantages of conventional antennas.
[0026] Another object of an embodiment of the present invention is to provide an antenna which is particularly well adapted to uses in moist environments.
[0027] Another object of an embodiment of the present invention is to provide an inductive antenna of low thickness (thickness smaller than one millimeter), requiring no additional insulator in a moist environment.
[0028] An object of an embodiment of the present invention is to provide a solution requiring no modification of the transponder support.
[0029] To achieve all or part of these and other objects, the present invention provides an inductive antenna comprising:
[0030] an insulating substrate;
[0031] a first planar conductive winding on a first surface of the substrate, interrupted at regular intervals to form a series of pairs of first conductive tracks;
[0032] a second planar conductive winding on a second surface of the substrate facing the first winding, the interruptions in the second winding facing the interruptions in the first winding to form a series of pairs of second conductive tracks; and
[0033] wherein:
[0034] each pair of first tracks defines, with the facing pair of second tracks, a resonant subassembly;
[0035] the first two tracks of a same subassembly are not interconnected and are each electrically connected to one and only one other first track of another subassembly or to a terminal of the antenna;
[0036] the second tracks of neighboring pairs are not electrically interconnected; and
[0037] one end of each first track is:
[0038] electrically connected to one end of a second track of the concerned subassembly; or
[0039] unconnected, the second tracks of the concerned subassembly being then electrically interconnected.
[0040] According to an embodiment of the present invention, the substrate is flexible.
[0041] According to an embodiment of the present invention, the antenna has a thickness smaller than 1 millimeter.
[0042] According to an embodiment of the present invention, the antenna comprises at least two subassemblies.
[0043] According to an embodiment of the present invention, the antenna further comprises a half-subassembly formed of a first track opposite to a second track and coupled to at least one subassembly.
[0044] The present invention also provides a resonator comprising an antenna having interconnected terminals.
[0045] The present invention also provides an electronic tag adapted to moist environments, comprising an electronic circuit connected to an antenna.
[0046] According to an embodiment of the present invention, a matching circuit comprising at least one inductive element and one capacitive element is interposed between the antenna and the electronic circuit.
[0047] The present invention also provides a duct comprising at least one electronic tag.
[0048] The present invention also provides a package comprising at least one electronic tag.
[0049] The present invention also provides an electromagnetic transponder comprising an electronic tag and a sensor connected to the electronic circuit.
[0050] The present invention also provides the use of a tag in the ground.
[0051] The present invention also provides a duct comprising at least one resonator.
[0052] The present invention also provides a package comprising at least one resonator.
[0053] The present invention also provides an electromagnetic transponder comprising at least one resonator and a sensor connected to the electronic circuit.
[0054] The present invention also provides the use of a resonator in the ground.
BRIEF DESCRIPTION OF THE DRAWINGS
[0055] The foregoing and other objects, features and advantages of the present invention will be discussed in detail in the following non-limiting description of specific embodiments in connection with the accompanying drawings, among which:
[0056] FIG. 1 , previously described, schematically shows in the form of blocks an example of a radio frequency transmission system to which the present invention applies;
[0057] FIG. 2 , previously described, is a simplified representation of an installation to which the present invention more specifically applies;
[0058] FIG. 3 , previously described, is a simplified perspective view, partially in cross-section, of a known technique;
[0059] FIG. 4 is a block diagram of an embodiment of a transponder according to the present invention;
[0060] FIG. 5 is a perspective view of an antenna according to an embodiment of the present invention;
[0061] FIG. 6 is a cross-section view along plane VI of FIG. 5 ;
[0062] FIG. 7 is a simplified cross-section view of a first type of subassembly of an antenna according to the present invention;
[0063] FIG. 7A shows the equivalent electric diagram of the subassembly of FIG. 7 ;
[0064] FIG. 8 is a simplified cross-section view of a second type of subassembly of an antenna according to an embodiment of the present invention;
[0065] FIG. 8A shows the equivalent electric diagram of the subassembly of FIG. 8 ; and
[0066] FIG. 9 schematically illustrates another example of application of an antenna according to the present invention.
DETAILED DESCRIPTION
[0067] The same elements have been designated with the same reference numerals in the different drawings, which have been drawn out of scale. For clarity, only those elements which are useful to the understanding of the present invention have been shown and will be described. In particular, the base stations for which the transponder antennas which will be described are intended have not been detailed, the invention being compatible with the various current base stations and detectors and requiring no modification thereof. Further, the modulation signals of the load formed by the transponder have not been detailed either, the invention being compatible with signals currently used for this type of transponders. The invention is further compatible with electronic tags currently available for this type of transponders.
[0068] To make the tuning of the tag insensitive to the moist environment in which it is stuck, it is provided to increase the capacitive value of its resonant circuit. Thus, the stray capacitances present between the different circuit portions and dependent on the environment permittivity only bring, even with a high permittivity, a negligible contribution to the tuning of the resonant circuit. A difficulty then is to decrease the inductance value necessary to compensate for the capacitance increase for a given resonance frequency (in applications more specifically targeted by the present invention, between 10 and 100 MHz). To decrease the inductance, it could have been devised to decrease the number of turns of planar windings forming the antenna (the inductance varies as the square of the number of turns). However, decreasing the number of turns also decreases the voltage recovered across the antenna (the recovered voltage varies as the number of turns). Now, the recovered voltage must be sufficient to extract the power necessary for the operation of the tag chip.
[0069] It could have been devised to increase the format of the inductance (the recovered voltage varies as the square of the scale factor) while decreasing the number of turns (the inductance varies as the scale factor). However, the antenna size which would then be necessary would often be incompatible with the application.
[0070] Further, the thickness constraint prevents the use of discrete components, which may be necessary, especially to incorporate a capacitive element of high value.
[0071] It is thus provided to split the circuit of the resonant inductive antenna into subassemblies or into pairs of sections interconnected in a specific way to form resonant subassemblies all having the same resonance frequency, each subassembly having a sufficiently low inductance value for the capacitive element taking part in the concerned subassembly to have a value sufficient to make stray capacitances depending on the moist environment permittivity negligible, even with a high permittivity.
[0072] In a simplified embodiment, the terminals of the resonant antenna thus formed are directly interconnected. A simple resonator having frequency tuning and quality factor characteristics which are not negatively altered by a moist environment is thus obtained, such a resonator being capable of responding to simple marking applications.
[0073] In an embodiment capable of working with an electronic chip, it may be necessary to interpose a matching circuit between the inductive resonant antenna and the electronic chip.
[0074] FIG. 4 is a block diagram of such an embodiment.
[0075] A resonator 4 (ANT) formed of resonant subassemblies, examples of which will be described hereafter, is connected to an electronic chip 22 via a matching circuit 5 . Such a matching circuit is for example formed of an inductance (for example, a planar inductive winding) in series with the resonator windings. A capacitive element C 2 takes part in the matching but may be integrated in chip 22 , as shown. Element C 2 is in parallel with the electronic circuits of chip 22 . Inductance L 2 ′ is preferentially of small size as compared with resonant inductive antenna 4 . Inductive element L 2 ′ is selected so that circuit L 2 ′C 2 is tuned to the frequency of the radio frequency field, to obtain an overvoltage effect. Inductive element L 2 ′, which does not need to recover a voltage induced by the radio frequency magnetic field, will preferably be selected to have a small size, whereby the disturbances introduced by the moist environment on the resonance characteristics of circuit L 2 ′C 2 only slightly influence the tag operation. In the following description, term “antenna” will designate resonant inductive antenna 4 .
[0076] FIG. 5 is a simplified perspective view of an embodiment of an antenna 4 for a transponder 2 ′ in a moist environment.
[0077] FIG. 6 is a cross-section view along plane VI of FIG. 5 .
[0078] Antenna 4 is formed of two identical planar conductive windings 42 and 44 on the two surfaces of an insulating substrate 46 . The windings are placed vertically above each other. The substrate is, for example, a flexible insulating sheet of the type currently used for planar antennas. The windings are interrupted, preferably at regular intervals, to form on each surface of the substrate an assembly of stacked identical conductive tracks forming micro-strip line sections, such microstrip line sections being contiguously gathered by two according to the layout of the windings forming resonant subassemblies.
[0079] Term “winding” is used to designate a geometrical figure equivalent to a winding of at least two conductive track turns.
[0080] When speaking of a planar winding or of a planar antenna, this does not exclude for the substrate to be flexible so that, in the end, the antenna takes the shape of the device (for example, the pipe) on which it is placed.
[0081] In a same resonant subassembly, the conductive tracks of the two line sections are connected to the geometrical point of continuity according to the layout of the windings according to two embodiments which will be discussed hereafter. The resonant subassemblies are interconnected according to the layout of the windings between one end of a first subassembly connected to a terminal 41 of antenna 4 and one end of a last subassembly connected to a terminal 43 of antenna 4 . The connections are performed by means of electric connections on a same surface or of through electric connections from one surface to the other (vias).
[0082] According to the embodiment of FIG. 5 , the antenna is formed of three resonant subassemblies (which are respectively identified by the two first digits 52 , 54 , and 56 of the reference numerals) of two microstrip line sections forming an assembly of four conductive tracks, each subassembly comprising two first tracks 522 , 524 , 542 , 544 , 562 , 564 on the first surface of the substrate opposite to two second tracks 526 , 528 , 546 , 548 , 566 , 568 on the second surface. The first microstrip line sections of each subassembly are respectively formed of track pairs 522 and 526 , 542 and 546 , 562 and 566 , and the second sections are formed of track pairs 524 and 528 , 544 and 548 , 564 and 568 . The two tracks of a same resonant subassembly and of a same surface are geometrically one after the other in the corresponding winding 42 or 44 .
[0083] Thus, a first terminal 41 of antenna 4 is connected to a first end 5222 of a track 522 (for example, arbitrarily forming a half-loop) having its second end 5224 facing, without being connected thereto, a second end 5244 of a track 524 of a first subassembly 52 . Track 524 continues winding 42 and is connected (connection 582 ), by its first end 5242 , to first end 5422 of a track 542 of second subassembly 54 . This structure is repeated all along first winding 42 . Thus, a first end 5622 of a track 562 of third subassembly 56 is electrically connected (connection 584 ) to end 5442 of track 544 of subassembly 54 . A second end 5624 of track 562 faces (without being connected thereto) second end 5644 of a track 564 of subassembly 56 . A first end 5642 of track 564 ends the winding by a connection to a second terminal 43 of the antenna.
[0084] On the second surface side, an identical pattern is repeated with second tracks 526 , 528 , 546 , 548 , 566 , and 568 of subassemblies 52 , 54 , and 56 . The first respective terminals 5262 , 5462 , 5662 , 5282 , 5482 , and 5682 of tracks 526 , 546 , 566 , 528 , 548 , and 568 are however left floating.
[0085] In the embodiment of FIG. 5 , second respective ends 5224 , 5424 , and 5624 of tracks 522 , 542 , and 562 of first winding 42 are connected (for example, by vias, respectively 523 , 543 , and 563 ) to second respective ends 5284 , 5484 , and 5684 of tracks 528 , 548 , and 568 of the corresponding subassembly, formed in second winding 44 . Second respective ends 5244 , 5444 , and 5644 of tracks 524 , 544 , and 564 of first winding 42 are connected to second respective ends 5264 , 5464 , and 5664 of tracks 526 , 546 , and 566 of the corresponding subassembly, formed in second winding 44 .
[0086] As a variation, connections 582 and 584 are on winding 44 (respectively connecting ends 5462 and 5282 and ends 5662 and 5482 ) and second ends 5422 , 5622 , 5242 , and 5442 of tracks 542 , 524 , 562 , and 544 are left floating. In this variation, the terminals of the antenna then correspond to ends 5262 and 5682 of tracks 526 and 568 .
[0087] Both surfaces are covered with an insulating varnish 482 , 484 ( FIG. 6 ), after an electronic circuit (chip 22 ) has been arranged thereon, possibly with an interposed matching circuit 5 . The assembly can then be arranged (for example glued) on the external surface of pipe 3 . Finally, an insulating film 49 is arranged on the assembly.
[0088] It can be considered that each resonant track subassembly 52 , 54 , 56 represents a Moebius-type connection between two line sections (see, for example, article “Analysis of the Moebius Loop Magnetic Field Sensor” by P. H. Duncan, published in IEEE Transaction on Electromagnetic Compatibility, May 1974 which describes a Moebius-type connection with two coaxial line sections). The different resonant subassemblies are then geometrically arranged end to end in an involute shape, the electric connection between two adjacent subassemblies being preferably performed in a single conductive level. There is no electric continuity via a same subassembly between the two electric connections which connect this subassembly to the adjacent subassemblies or to terminals 41 , 43 of antenna 4 .
[0089] FIG. 7 is a cross-section view of one of the subassemblies (for example, resonant subassembly 54 ) of FIG. 5 in an unwound representation.
[0090] FIG. 7A shows the equivalent electric diagram of subassembly 54 of FIG. 7 .
[0091] Each first track 542 or 544 formed in the first conductive level or winding is connected, by its second end and by connection 543 , respectively 545 , to second track 548 or 546 vertically above the other first track in the other level or winding (crossed connection). The first ends of tracks 542 and 544 define terminals of access to the subassembly, respectively connected to the access terminals of adjacent subassemblies 52 and 56 . The first ends of tracks 546 and 548 are left floating.
[0092] From an electric viewpoint and as illustrated in FIG. 7A , the equivalent electric diagram of such a subassembly amounts to electrically arranging, in series, an inductance of value L 54 and a capacitor of value C 54 . Inductance L 54 represents the inductance of a single conductive track equivalent to the association of the conductive tracks of subassembly 54 , plus the mutual inductances between this equivalent track and the equivalent tracks associated in the same way with the other subassemblies. Capacitor C 54 represents the capacitance formed by the tracks of subassembly 54 between tracks 542 and 544 of the first level and tracks 546 and 548 of the second level (taking into account the electric permittivity of insulating substrate 46 ). The different resonant circuits are electrically series-connected to form the antenna.
[0093] The impedance of resonant subassembly 54 is, in this embodiment (neglecting ohmic losses in the conductive tracks and dielectric losses), Z=jL 54 ω+1/jC 54 ω.
[0094] FIG. 8 is a cross-section view of a subassembly according to a second embodiment.
[0095] According to this second embodiment, the second respective ends of tracks 542 and 544 of the first winding are left floating (unconnected) and the second respective ends of tracks 546 and 548 of the second winding of a same subassembly are interconnected (connection 57 ). The rest is not modified with respect to the first embodiment.
[0096] From an electric viewpoint and as illustrated in FIG. 8A , assuming that the tracks are of same length in the two embodiments, the embodiment of FIGS. 8 and 8A amounts to a series connection of an inductive element of value L 54 with a capacitive element of value C 54 /4, where L 54 and C 54 represent the inductances and capacitances of subassembly 54 defined in relation with FIG. 7A .
[0097] The impedance of a pair of sections in this embodiment is (neglecting ohmic losses in the conductive tracks and dielectric losses), Z=jL 54 ω+1/j(C 54 /4)ω
[0098] This embodiment decreases the equivalent capacitance but avoids interconnection vias in each subassembly.
[0099] The two above embodiments may be combined.
[0100] The specific provided antenna structure enables, for a given tuning frequency, to form inductive subassemblies of small value, and thus associated with capacitances of high values (and thus insensitive to the variation of stray capacitances sensitive to the moist environment).
[0101] Advantage is thus taken of the dielectric thickness, which enables to form a non-negligible capacitance (greater than 150 pF).
[0102] The lengths will then be adapted to the operating frequency of the antenna so that each subassembly respects the tuning, that is, LCω 2 =1 (L 54 C 54 ω 2 for subassembly 54 according to the embodiment of FIG. 7A and L 54 C 54 /4ω 2 for subassembly 54 according to the embodiment of FIG. 8A ).
[0103] It is possible to use an approximate rule to size the antenna. To achieve this, unit inductance L 0 is considered to be equal to the inductance of a winding equivalent to the parallel association of two windings 42 and 44 divided by the squared number of turns (the number of turns common to windings 42 and 44 ). General capacitance C 0 is also considered to be equal to the total capacitance comprised between the tracks of the first level and the tracks of the second level, taking into account the electric permittivity of insulating substrate 46 . If n resonant subassemblies are regularly distributed per turn of the winding, the approximate rule to be respected is L 0 C 0 (ω/n) 2 =1 in the first embodiment ( FIG. 7 ) and L 0 (C 0 /4) (ω/n) 2 =1 in the second embodiment ( FIG. 8 ). In the case where the resonant subassemblies take up more than one turn, the number of turns is taken into account. For example, for more than two turns n=1/2 will be selected.
[0104] The equivalent impedance of antenna 4 can be deduced from a series connection of impedances Z of each subassembly. The voltage recovered by antenna 4 , when placed in a magnetic field, may be calculated according to the load connected to the antenna, considering that a voltage source is inserted in series with its equivalent impedance. The value of this voltage source corresponds to the electromotive force which would be induced by the radio frequency magnetic field in a winding equivalent to the parallel association of windings 42 and 44 .
[0105] It can be seen that the lengths of the conductive elements and the capacitive values can thus be varied according to the distribution of the subassemblies of one or the other of the embodiments. The values of the capacitive elements are now no longer negligible and the antenna is less sensitive to disturbances due to its environment.
[0106] This way of forming an antenna further enables to split the electric circuit and avoids inductive elements having too long a length where the current would not be able to circulate in homogeneous fashion (amplitude and phase). Indeed, the interconnection of the pairs amounts to series-connecting several resonant circuits of same resonance frequency. The lower the values of the circuit inductances, the lower current drifts by stray capacitance effects will be.
[0107] The different subassemblies do not necessarily have the same length, provided for each subassembly to respect the resonance relation, possibly with an interposed capacitor.
[0108] Capacitors may be interposed between different subassemblies. However, to avoid adversely affecting the thickness, it will be preferred to vary the thickness of substrate 46 .
[0109] In the embodiment illustrated in FIG. 5 , the used thicknesses preferably have the following orders of magnitude:
[0110] substrate 46 : less than 200 μm;
[0111] conductive layers for forming windings 42 and 44 : less than 50 μm, for example, 35 μm;
[0112] varnish 482 and 484 : on the order of a few tens of μm;
[0113] film 49 : at most a few hundreds of μm, preferably less than 100 μm.
[0114] Such thicknesses may vary, but it can be seen that the formed transponder is particularly thin (of a thickness smaller than 1 mm in the preferred embodiment) while being insensitive to variations of the stray capacitances due to the presence of the moist environment.
[0115] As a specific embodiment, an antenna such as illustrated in FIG. 5 and adapted to an operation at a 13.56-MHz frequency has been formed on a substrate having a 100-μm thickness with a 42.5-pF/cm 2 capacitance, in the form of five rectangular loops on each surface of the substrate with the following characteristics (neglecting length variations between subassemblies):
[0116] loop size: approximately 210 mm per 50 mm;
[0117] width of the copper tracks arranged on the substrate (1.82 mm);
[0118] inductance L 0 =300 nH;
[0119] capacitance C 0 =1,850 pF, that is C 54 =185 pF in the first embodiment and C 54 =370 pF (C 54 /4=93 pF) in the second embodiment.
[0120] The practical forming of the antenna, and thus of the transponder, is within the abilities of those skilled in the art based on the functional indications provided hereabove and by using manufacturing techniques current in the manufacturing of integrated circuits on a thin flexible support. In particular, the forming of the interconnects between levels in the embodiment of FIGS. 5 and 7 may require offsetting the respective ends of the tracks in each of the windings.
[0121] FIG. 9 illustrates another example of application of an antenna adapted to moist environments. According to this example, an electronic tag 2 ′ comprising such an antenna 4 is arranged on a fresh product packaging (packages may contain different fresh products having various water contents, they may or not be covered with frost, the products thus packaged may be stacked or not, in orderly manner or in bulk).
[0122] An advantage of the described structures is that they are compatible in terms of reception of a magnetic flow (and of emission of a magnetic field, considering the current circulating along the antenna) with windings having a large number of turns, preferably between 5 and 15 turns.
[0123] FIG. 10 is a simplified representation of an antenna according to another embodiment. As in the previous embodiments, the antenna comprises at least two subassemblies 50 , each formed of two pairs 500 of tracks coupled to each other by a connection 57 or by connections 543 and 545 . This structure is completed by a half-subassembly 500 formed of an additional pair of tracks. It is possible for the half-subassembly to be interposed between two subassemblies rather than being at the end of the antenna. The presence of the additional half-subassembly may be used to adjust the antenna length, to transfer the end terminals of the antenna onto a same surface of the substrate, etc.
[0124] As specific embodiments, inductive antennas respecting the described structure have been formed with the following dimensions.
Example 1
[0125] Substrate: material known under trade name Kapton with a 50-μm thickness (∈ r =3.3).
[0126] Winding: rectangular spiral of 5 rectangular loops, respectively of 47.5*212 mm, 50.5*215 mm, 53.5*218 mm, 56.5*221 mm, and 59.5*224 mm.
[0127] Width of the conductive tracks: 1.07 mm.
[0128] Track interruptions: two pairs of tracks per loop (interruptions in the middle of each small side of each loop and middles of the subassemblies in the middle of the large sides).
[0129] Type of subassemblies: cross-connection of the type of connections 543 and 545 , that is, one end of each first track is electrically connected to one end of a second track of the concerned subassembly. Ten subassemblies as a whole.
Example 2
[0130] Substrate: material known under trade name Kapton with a 50-μm thickness (∈ r =3.3).
[0131] Winding: rectangular spiral of 6 rectangular loops, respectively of 47*211.75 mm, 49.5*214.25 mm, 52*216.75 mm, 54.5*219.25 mm, 57*221.75 mm, and 59.5*224.25 mm.
[0132] Width of the conductive tracks: 0.89 mm.
[0133] Track interruptions: one pair of tracks per loop (interruptions in the middle of each small side of each loop and middles of the subassemblies in the middle of the other small side).
[0134] Type of subassemblies: straight connection on a surface of the type of connections 57 , that is, one end of each first track is unconnected, the second tracks of each subassembly being interconnected. Six subassemblies as a whole.
Example 3
[0135] Substrate: material known under trade name FR4 with a 100-μm thickness (∈ r =4.8).
[0136] Winding: rectangular spiral of 6 rectangular loops, respectively of 20*100 mm, 18*98 mm, 16*96 mm, 14*94 mm, 12*92 mm, and 10*90 mm.
[0137] Width of the conductive tracks: 0.66 mm.
[0138] Track interruptions: one pair of tracks per batch of two loops (interruptions and middles of the subassemblies in the middle of a same small side of each loop).
[0139] Type of subassemblies: cross-connection from one surface to the other.
[0140] Other applications of such an antenna and of such a transponder can be envisaged. For example, one or several sensors of physical variables, for example, pressure, temperature, hygrometry, etc. may be connected to the electronic circuit of the transponder, data representative of these variables being transmitted to a distant reader by means of the antenna.
[0141] The loop antenna described in document WO 2008/083719 may at most correspond to one of the subassemblies of the described inductive antenna.
[0142] Various embodiments have been described, and various alterations and modifications will occur to those skilled in the art. In particular, the dimensions to be given to the conductive tracks depend on the application and their calculation is within the abilities of those skilled in the art based on the functional indications given hereabove and on the resonance frequency and on the desired antenna size. | The invention relates to an inductive antenna, comprising: a first planar conductive winding ( 42 ) on a first surface of a substrate, said first winding being cut off at regular intervals so as to form a series of pairs of first conductors ( 522, 524; 542, 546; 562, 564 ); and a second planar conductive winding ( 44 ) on a second surface of the substrate, said second winding being provided opposite the first winding and cut off in a direction vertically perpendicular to that of the cutoffs of the first winding so as to form a series of pairs of second conductors ( 526, 528; 546, 548; 66, 568 ). Each pair of first conductors defines a resonant subassembly with the pair of second conductors opposite thereto, wherein each of the two first conductors of a single subassembly are electrically connected to another first conductor of another subassembly or to a terminal ( 41, 43 ) of the antenna, the second conductors of adjacent pairs are not electrically connected to each other, and one end ( 5224, 244, 5424, 5444, 5624, 5644 ) of each first conductor is either electrically connected ( 523, 543, 563, 525, 545, 565 ) to one end ( 5284, 5264, 5484, 5464, 5684, 5664 ) of a second conductor of the subassembly in question or is not connected thereto, in which case the second conductors of the subassembly in question are electrically connected to one another. | 7 |
BACKGROUND OF THE INVENTION
It is well known that there is a need for maintaining the purity of various of the nitrogen oxides for critical uses in many high technology industries. Nitrogen forms a multiple of oxides which readily attack the iron-containing metals of the apparatus typically used in their manufacture, transport and/or storage, thus creating significant problems when the maintainence of a desired level of purity is required. For example, it is well known that need exists for the supply of highly pure grades of nitrogen tetroxide propellants for use as oxidizers for rocket engines during system design and development tests, at the launching sites of vehicles to be projected into space and in orbit, such as satellites, space shuttles, or the like. Propellant supply/oxidizer flow rate decay problems associated with impure propellant such as are prone to interfere with design/testing programs and launch scheduling of the vehicle, as well as its space flight life duration prospects have plagued the industry. For example, the publication "Flow Decay", pages 101, 103, 104, 115, 117, 122, 124, 126, 132, 133, 135, 136, and 139 of Final Scientific Report, June 30, 1972, AFRPL-TR-72-84 reports on various problems within the current state of the art.
Such problems are now of major concern due to the recent emergence of nitrogen tetroxide propellants as major oxidizers for liquid propellant rocket engines and occur in connection with the storing, transferring, testing, launching and maneuvering operations of satellites, MX missiles, space shuttles and the like. These problems are caused by the tendency of such oxidizers to corrode their storage, transport and transfer containers, as well as other iron-containing metal parts of the engine oxidizer supply system. Commercially available nitrogen tetroxide propellants are supplied to the test site or launch pad mounted vehicle, either into the vehicle inboard supply tanks or into close-by "ready storage" ground-based intermediary relay tanks. The tanks, piping, valves, etc., components furnished by manufacturers are typically made of stainless steel alloys and are invariably surface-coated by potentially contaminating materials such as metallic oxides and salts, as well as manufacturing residues such as oils, greases, grime, bits of metal and shop dirt. Unless such contaminants are initially completely removed from such components of the system, upon introduction of nitrogen tetroxide therein, undesired chemical reactions are fostered and contaminants are loosened and freed to enter the nitrogen tetroxide supply in suspension. Such materials in suspension tend to plug the filters and other components by way of example in a rocket engine propulsion system, such as the valves and injection orifices; thereby seriously interfering with the propellant transfer operations as well as the test or vehicle launching operations. Furthermore, and perhaps more importantly, the incidence thereof seriously reduces the reliable duration prospect of the rocket engine performance. Typical pre-storage and transfer/operational ambient temperature conditions contribute to these problems. Regardless of how pure the furnished nitrogen tetroxide may be, its introduction into an improperly prepared system will limit its usefulness.
Previously, various steps were taken to "clean" the components of such systems subsequent to their manufacture, employing well-known agents for removing the residues recognized to be potential contaminants and/or reactants for the nitrogen tetroxides to be handled. However, that state of the art did not qualify to satisfy the needs of present day technologies requiring the use of higher purity nitrogen tetroxide. The present invention is the result of the discovery that a novel combination of chemical agents, applied in a specific sequence, will prepare iron-containing metal components to perform with improved efficacy.
As a result of a professional search conducted with respect to this invention, applicant is aware of U.S. Pat. Nos. 3,522,093; 3,598,741; 3,553,016; 2,992,945; 3,401,061; 3,880,681; and 3,510,432. Each of these references is considered relevant to the subject of cleaning and/or passivating apparatus, but none teach the specific procedures disclosed and claimed herein.
One object of the present invention is to provide new and improved methods for chemically cleaning iron-containing metal surfaces of apparatus which may contact a nitrogen oxide.
Another object of the present invention is to provide a method for chemically cleaning stainless steel surfaces of apparatus used in the manufacture, transportation, storage and/or use of high purity nitrogen oxides.
A further object of the present invention is to provide chemically cleaned stainless steel apparatus which will markedly increase the shelf life of nitrogen oxides manufactured, transported and/or stored therein over that of similar uncleaned apparatus.
A still further object of the present invention is to provide a process for chemically cleaning chromium containing stainless steel apparatus used in the manufacture, transport, and/or storage of nitrogen tetroxide.
These and other objects of the present invention will become apparent to those skilled in the art from a consideration of the following specification and claims.
SUMMARY OF THE INVENTION
Nitrogen combines with oxygen to form a variety of nitrogen oxides all of which generally act as oxidizers. As used within this application the term "nitrogen oxide" refers to Nitric Oxide (NO); Nitrogen Trioxide (N 2 O 3 ); Nitrogen Dioxide (NO 2 ); Nitrogen tetroxide (N 2 O 4 ); and mixtures thereof. Each of these oxides of nitrogen is generally well known and can be prepared by methods known in the prior art. Each of these oxides of nitrogen is generally used for its oxidizing capability and it is this capability which generally creates the problems associated with maintaining purity and shelf life of the oxide when exposed to iron-containing metal surfaces.
The method of the present invention is a process for cleaning and passivating stainless steel surfaces of apparatus used in the manufacture, transportation and/or storage of nitrogen oxides comprising the steps of:
1. Cleaning said surface by contacting with an alkaline cleaner containing solution to remove fouling deposits and thereafter rinsing with water;
2. Pickling said surface by contacting with an aqueous nitric acid/hydrofluoric acid solution to remove oxides, carbonates and mill scale, and thereafter rinsing with water;
3. Passivating said surface by contacting with nitric acid passivation solution and thereafter rinsing with water;
4. Pickling said surface by contacting with a nitrogen tetroxide solution and thereafter rinsing with water;
5. Cleaning said surface by contacting with a citric acid solution and thereafter rinsing with water;
6. Rinsing said surface with distilled or de-ionized water until said surface is chloride free; and
7. Purging said surface free of liquid with hot nitrogen.
The process of the invention also provides specifically for an alternate step 2a which comprises contacting said surface with an alkaline permanganate solution and thereafter rinsing with water between steps 2 and 3 to remove smut which may be detected at the completion of step 2; and for an alternate step 5a which comprises contacting said surface with a nitric acid solution and water rinse between steps 5 and 6 to remove smut which may be detected at the completion of step 5 or successive such treatments in the event smut continues to be detected.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a flow diagram illustrating the steps comprising the invention wherein an iron-containing metal surface is contacted with various solutions in accordance with the process of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Typically, the metal surfaces treated in accord with the process of the invention are the interior surfaces of tanks, reactors, tubing, piping valves and containers of the like through or in which a nitrogen oxide as afore described, is being manufactured, transported and/or stored. Typically such apparatus is made from chromium containing steel alloys particularly various alloys of iron such as stainless steels containing chromium, nickel and/or other components such as manganese and titanium. Typical stainless steels used for containing high purity nitrogen oxides contain from about 4% to about 20% chromium. Some typical stainless steels used . in nitrogen oxide apparatus include AISI type Nos. 304, 304L, 316, 316L, 321 and 347.
In accord with a preferred embodiment of the invention, as illustrated in the drawing, typical apparatus would first be cleaned by contacting with an alkaline cleaner to remove the more apparent deposits of oil, grease, dirt and grime. The alkaline cleaner can be any suitable alkaline cleaner and may contain chelating agents, surfactants or other additives which may serve to accelerate or otherwise improve the cleaning action thereof. The alkaline cleaner may be caustic soda based, caustic potash based or any of the alkaline phosphate salts such as trisodium or disodium phosphate salts or a combination thereof typically used for such purpose. The alkaline cleaner, in most applications, generally need only be circulated through the apparatus, however, it may also be agitated, heated, mechanically scrubbed or otherwise imposed upon the apparatus to foster the cleaning activity. Upon completion of such cleaning, the apparatus is rinsed with water to remove the alkaline cleaner and any loosened dirt, oils, grime or other contaminants.
It should be understood that the water used in the water rinse of step 1, as with all of the water rinses of the process of this invention with the exception of the distilled or de-ionized water rinse, need not be of critical quality and can generally be any reasonable quality water containing acceptable levels of normal contaminants or additives found in potable quality water. In all steps utilizing a water rinse, the rinse should be continued until the chemicals used in the step have been removed. I have found it convenient to continue rinsing until the quality of the water coming from the rinsing process is the same as the quality of the water being applied, to assure that the rinse is thorough. Such method of determining the adequacy of the water rinse is hereafter referred to as quality equilibrium. It should be understood, however, that quality equilibrium of the rinse water is not a limitation of my invention but merely a convenient means to determine the adequacy of the rinse.
Upon completion of the water rinse of step 1, the apparatus is subjected to pickling using an aqueous solution of nitric acid (HNO 3 ) and hydrofluoric acid (HF). Typically, such solution will vary in concentration dependant upon whether the acids are hot or cold, the condition of the apparatus as to rust and mill scale and the time allotted to the pickling process. Generally, however, lower ratios of HF and HNO 3 are used to avoid undesirable etching.
The aqueous concentration should be apparent to one of ordinary skill in the art upon inspection of the apparatus to be treated and the amount of rust and mill scale contained therein. The purpose of the mixture of the two acids is to provide different but complementary action to the pickling step. The hydrofluoric acid is added principally to obtain a cleaning and etching effect, while the nitric acid accelerates the solubility of oxides, particles of metal, carbonates, etc. After pickling the apparatus is water rinsed.
Upon completion of step 2, the apparatus and/or final volumes of waste rinse water should be carefully inspected for the presence of "smut". The presence of smut, a dark particulate which typically develops on the metal surface during the chemical reaction of the pickling acids on the mill scale, can be detected by visually inspecting the metal surface, for example by wiping or otherwise, and can also be detected by filtering the final volumes of rinse water. If smut persists on the apparatus surface or in the rinse water then the apparatus should be subjected to step 2a comprising alkaline permanganate treatment and rinse. In the event smut is not detected the alkaline permanganate step is not necessary and one can proceed directly to the nitric acid passivation step 3.
The alkaline permanganate solution of step 2a, can be any suitable alkaline permanganate solution. Typically, the sodium or potassium permanganates are utilized in aqueous solution for this step directly from their preparation in strongly alkaline solution. Typically such solution will contain at least about 12% alkaline hydroxide and at least about 3% permanganate by weight. When treating apparatus which will contain nitrogen tetroxide, the use of potassium permanganate is preferred. After treatment with the alkaline permanganate the apparatus is water rinsed. The purpose of this step 2a is to remove any smut and normally this is accomplished with a single treatment and rinse. The apparatus should be again inspected for smut and if detected this step 2a can be repeated until smut is no longer detected.
Upon completion of step 2, or step 2a if appropriate, the apparatus surface is subjected to HNO 3 passivation in accord with step 3. The pickling process acts in part to irregularly remove or destroy the passive protective film on the apparatus surfaces as a result of contact with the HNO 3 /HF environment, and passivation is affected by the treatment with HNO 3 (with or without wetting agents or other additives) which acts to form an adherent passive coating thereon. Passivation is achieved by contacting the apparatus surface with an aqueous solution of nitric acid. Typically such solution will contain from about 30% to about 50% by volume of nitric acid. Thereafter the apparatus surface is water rinsed. In instances where the apparatus has limited exposure to ambient atmosphere after completion of step 2, or step 2a as appropriate, step 3 may not be required and the process can move directly to step 4.
Upon completion of the HNO 3 passivation in step 3, the surface is again subjected to pickling, this time with nitrogen tetroxide solution in accord with step 4. I have found that pickling with the nitrogen oxide at this stage in the process, particularly with green nitrogen tetroxide, has the effect of loosening remaining oxides or scales without apparently destroying the effect of any prior steps. The inclusion of this step after HNO 3 /HF pickling and HNO 3 passivation appears to have a controlling influence on the quality of the cleaned and passivated apparatus rendering it particularly suitable for handling high purity nitrogen oxide compounds. Green nitrogen tetroxide is an equilibrium of nitrogen tetroxide, nitrogen dioxide and nitric oxide, the solution containing not less than about 1% of nitric oxide in nitrogen tetroxide. After pickling, the surface is water rinsed and subjected to a citric acid treatment in accord with step 5.
The citric acid treatment of step 5 appears to act in fostering the removal of contaminants which had been loosened in pickling step 4 but which had not been sufficiently loosened to be removed by the water rinse. While not wishing to be bound by any theory of action, the citric acid treatment appears to break or loosen the bond between the oxide and the base metal. I have found generally that application of steps 4 and 5 effect the removal of any pertinent contaminants left after the pickling of step 2, without necessitating the repassivation of the surface. However, in the event that smut is detected after the water rinse as previously described, it is necessary to again passivate, designated as step 5a in accord with the guidelines of step 3, ending with a water rinse.
At the completion of step 5 or 5a as may be appropriate, the cleaned and passivated apparatus surface is ready for the final steps of distilled or de-ionized water rinse (step 6) and nitrogen purge (step 7). The purpose of the distilled or de-ionized water rinse of step 6 is to remove any contaminants, especially chlorides, which may be contained in the less than ideal water utilized in the water rinse of steps 5 or 5a. As with the ordinary water rinse, one method of determining the adequacy of the distilled water rinse of step 6 is continuation through quality equilibrium.
The nitrogen purge of step 7, preferably conducted at elevated temperatures, acts in the removal of residual water from step 6 and places the apparatus in cleaned and passivated condition ready for use. It has been found effective to maintain the apparatus surface under a nitrogen blanket until time for its use.
The following examples will illustrate the process of the present invention and are not to be construed as a limitation thereof.
EXAMPLE 1
A one ton capacity, stainless steel (AISI No. 304), shipping cylinder was subjected to the following process steps:
(1) The cylinder was filled with an aqueous solution of commercially available Oakite® 24 alkaline cleaner (about 8 oz Oakite/gal water), which was maintained therein for about 15 minutes at about 180° F. The cylinder was then drained and rinsed with tap water until quality equilibrium was demonstrated.
(2) The cylinder was then refilled with an aqueous solution containing about 30 parts by volume of 70% by weight aqueous nitric acid, about 2 parts by volume of 50% by weight aqueous hydrofluoric acid and the remainder tap water. Both acids were commercial grade. The solution was maintained within the cylinder for about 15 minutes at about 150° F. The cylinder was thereafter drained and flushed with water until quality equilibrium was demonstrated. The interior surface of the cylinder was inspected for smut--none was found.
(3) The cylinder was refilled with an aqueous solution containing about 40 parts by volume of 70% by weight (commercial grade) aqueous nitric acid and about 60 parts by volume of tap water. The solution was maintained in the cylinder at about 80° F. for about 30 minutes and thereafter the cylinder was drained and rinsed with tap water to quality equilibrium. Because there was to be an indefinite delay before performing the next step, the cylinder was then purged with nitrogen gas at about 120° F. until dry.
(4) The cylinder was refilled with green nitrogen tetroxide containing about 0.5% by weight nitric oxide and maintained at about 75° F. for 30 months. The cylinder was thereafter drained, purged of fumes with gaseous nitrogen and rinsed with tap water at ambient temperature (about 75° F.) to quality equilibrium.
(5) The cylinder was refilled with an aqueous solution containing about 3% by weight citric acid at a temperature of about 160° F. The solution was agitated by means of a nitrogen stream and allowed to cool to ambient temperature (about 75° F.) over a period of approximately 24 hours. The cylinder was drained and flushed with tap water until quality equilibrium was demonstrated. The interior surface of the cylinder was inspected for smut--none was detected.
(6) The cylinder was flushed with de-ionized water at ambient temperature (about 75° F.) until quality equilibrium was demonstrated, particularly until the rinse water was chloride free.
(7) The cylinder was then purged with nitrogen gas at about 120° F. until dry. The cleaned and passivated cylinder was thereafter filled with pre-analyzed, nitrogen tetroxide. The contents were analyzed at the end of three weeks and no change in the analysis was detected.
EXAMPLE 2
A one pint capacity, stainless steel (AISI No. 304), sample container was subjected to the following process steps:
(1) The container was filled with an aqueous solution of commercially available Oakite® 24 alkaline cleaner (about 8 oz Oakite/gal water), which was maintained therein for about 15 minutes at about 180° F. The container was then drained and rinsed with tap water until quality equilibrium was demonstrated.
(2) The container was then refilled with an aqueous solution containing about 30 parts by volume of 70% by weight aqueous nitric acid, about 2 parts by volume of 50% by weight aqueous hydrofluoric acid and the remainder tap water. Both acids were commercial grade. The solution was maintained within the container for about 15 minutes at about 150° F. The container was thereafter drained and flushed with water until quality equilibrium was demonstrated. The interior surface of the container was inspected for smut--none was found.
(3) The container was refilled with an aqueous solution containing about 40 parts by volume of 70% by weight (commercial grade) aqueous nitric acid and about 60 parts by volume of tap water. The solution was maintained in the container at about 80° F. for about 30 minutes and thereafter the container was drained and rinsed with tap water to quality equilibrium. Because there was to be an indefinite delay before performing the next step, the container was then purged with nitrogen gas at about 120° F. until dry.
(4) The container was refilled with green nitrogen tetroxide containing about 0.5% by weight nitric oxide and maintained at about 75° F. for 60 months. The container was thereafter drained, purged of fumes with gaseous nitrogen and rinsed with tap water at ambient temperature (about 75° F.) to quality equilibrium.
(5) The container was refilled with an aqueous solution containing about 3% by weight citric acid at a temperature of about 160° F. The solution was agitated by means of a nitrogen stream and maintained at a temperature of about 160° F. over a period of approximately 24 hours. The container was drained and flushed with tap water until quality equilibrium was demonstrated. The interior surface of the container was inspected for smut--none was detected.
(6) The container was flushed with de-ionized water at ambient temperature (about 75° F.) until quality equilibrium was demonstrated, particularly until the rinse water was chloride free.
(7) The container was then purged with nitrogen gas at about 120° F. until dry. The cleaned and passivated container was thereafter filled with pre-analyzed nitrogen tetroxide. The contents were analyzed at the end of 3 weeks and no change in the analysis was detected.
EXAMPLE 3
Stainless steel tubing (0.218" I.D. AISI No. 304L) was treated in accord with Example 1. Smut was detected at the end of step 2 and the tubing was filled with an aqueous solution containing about 3% by weight potassium permanganate; about 12% by weight sodium hydroxide, and the remainder tap water. The solution was maintained in the tubing at about 200° F. for about 15 minutes. The tubing was then drained and flushed with tap water until quality equilibrium was reached. The process was thereafter continued in accord with Example 1 through step 3.
The tubing was then filled with pre-analyzed nitrogen tetroxide. When analyzed after being maintained for one month at about 120° F., it showed no significant change in analysis in comparison with a companion tube which was not treated with alkaline permanganate as set forth herein. | A process is disclosed for cleaning and passivating stainless steel apparatus used in the manufacture, transport, storage and/or use of nitrogen oxides. The process involves sequentially treating stainless steel surfaces of apparatus which contact a nitrogen oxide, with various solutions, in such manner as to enable the apparatus to substantially maintain the quality of the nitrogen oxide to be manufactured, transported, stored and/or used therein. Thus, for example, the purity of nitrogen tetroxide, used as a propellant for rocket engines and the like, may be maintained longer, the shelf life significantly increased and rocket engine flow decay problems markedly reduced through use of the disclosed cleaning and passivating process. | 1 |
This application is a continuation application of Ser. No. 418,925 filed Sept. 16, 1982, now abandoned, which is a continuation of Ser. No. 194,807 filed Oct. 7, 1980, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to implantable medical devices such as pacemakers, and more particularly, to a telemetry system for transmitting information from the pacemaker to a remote receiver for diagnostic purposes.
2. Description of the Prior Art
Pacemakers for providing stimulating pulses to the heart in the absence of natural cardiac activity are well-known. Originally, such pacemakers were fabricated from discrete analog components. More recently designed pacemakers employ digital circuitry realized in monolithic form. The additional complexity resulting from monolithic digital implementation has been used to provided desirable pacemaker features, including programmability. One example of such prior art is U.S. Pat. No. 4,276,883 granted July 7, 1981 to McDonald et al. This patent discloses a pacemaker having a number of programmable features including the pacing rate and pulse width. Information concerning these operating parameters is stored in digital form in the pacemaker's memory. After implantation it is desirable to read out these memory locations for diagnostic purposes. Additional information which is useful for diagnostic purposes, such a lead impedance, battery voltage, and the patient's intracardiac electrogram are inherently analog in nature and not directly compatible with the other digital information within the pacemaker. Consequently, conventional digital modems have not been applicable to pacemaker telemetry systems since their use would require the periodic conversion of the aforementioned analog data to a numerical value prior to transmission.
In contrast, the pulse interval telemetry system of the present invention is capable of transmitting analog data without conversion to a numerical value, and is capable of sequentially transmitting both digital and analog data. This data is individually and serially transmitted in either an analog or digital format to a remote receiver.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of the function elements of the system for encoding and transmitting information from the implanted medical device.
FIG. 2 is a truth table showing the relationship between the encoding scheme and the corresponding states of the various current sources of the system;
FIG. 3 is a waveform diagram showing the analog and digital data format; and
FIG. 4 is a schematic diagram showing the VFO, and current sources in a form suitable for implementation in a bipolar integrated circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
General
As previously described, the pulse interval modulation telemetry system is used to transmit analog and digital information from the implanted medical device to a remote receiver. In the context of a pacemaker application the analog information may include battery voltage, lead impedance, or the patient's intracardiac electrogram. Similarly, typical digital data may include programmed pulse width and rate settings as well as identification information. An example of a pacemaker suitable for use as a source of digital information is taught by the previously mentioned U.S. Pat. No. 4,276,883 granted July 7, 1981, to McDonald et al. This application discloses a digitally implemented pacemaker having memory for storing digitally programmed information shown in FIG. 6H of the referenced patent. This information is stored in a parallel format as a sequence of binary digits.
A suitable source for analog information such as the patient's intracardiac electrogram may be found in U.S. Pat. No. 4,266,551 granted May 12, 1981 to Stein et al. The circuitry disclosed in this patent may be used to provide a source of intracardiac analog information to the telemetry system of the present invention.
As shown schematically in FIG. 1 the heart 10 has an indwelling catheter 11 for sensing cardiac depolarizations and for stimulating cardiac tissue. Pacer logic receives signals via sense amplifier 34 and delivers stimulating pulses by way of output amplifier 33. The pacer logic 12 shown operates under the control of parameter data stored in memory 15. The memory 15 contains the parameter data in parallel form which is serialized for data transmission by shift register 16 which forms a portion of the telemetry system.
In operation, the transmission of data is remotely initiated by the closure of a magnetically actuated reed switch within the pacemaker in the well-known manner. Digital data is then transmitted twice to a remote receiver where it is decoded and checked for errors. The digital data transmission is followed by the transmission of analog data in an analog format. The telemetry system is disabled by removing the magnet from the pacemaker site which opens the reed switch and disables the telemetry circuitry.
Additionally, the telemetry circuitry of the present invention includes a receiver blanking circuit which permits the transmission of analog or digital data to be interrupted by the remote programmer thus truncating the transmission of telemetry information so that the pacemaker may receive higher priority programming information from the remote programmer. This function is achieved by digital circuitry which detects the presence of a long duration burst of RF energy from the remote programmer which is received by the pacemaker and which is decoded to turn off the telemetry transmission systems and to prepare the digital circuitry for the reception of programming information from the remote programmer.
Oscillators
Referring to FIG. 1 the radio frequency carrier signal is developed by a radio frequency oscillator tank in FIG. 1. The tank circuit 14 is energized at periodic intervals determined by a variable frequency oscillator (VFO) 12. Radio frequency energy from the reasonant tank circuit 14 is coupled to antenna 16 which radiates this energy to a remote receiver (not shown).
The repetition rate of the variable frequency oscillator is set by a number of cooperating current sources which establish a net charging rate at the input node 18 of the VFO 12. When operating in the digital mode for the transmission of digital information the current sources establish a first characteristic charging rate for encoding a logic one and a second characteristic charging rate for encoding a logic zero.
As shown in FIG. 1, three cooperating current sources 26, 28 and 30, are energized by control logic, operating switches 20, 22, 24. When each of these current sources is turned on, a characteristic current I, 0.5 I or 0.25 I is supplied to the capacitor 32 which establishes a voltage at node 18. When the voltage on capacitor 32 reaches a trip level, the VFO output will change state initiating a burst of RF energy from the tank circuit 14. Consequently, the time period between successive bursts of radio frequency energy will be determined by the number of current sources which are on. The truth table FIG. 2 indicates the relationship between the encoding scheme of the present invention and the states of the various current sources. As indicated in the diagram, the logic "one" signal is encoded by energizing current source 30 by closing switch 24, which provides a constant current charging rate to capacitor 32 of magnitude I. In the preferred embodiment this characteristic charging rate results in a pulse interval of 1,000 microseconds. Similarly, a logic "zero" is encoded by energizing the two current sources 28 and 30 resulting in a net charging current of 1.5 I which results in a shorter, 667 microsecond pulse interval. This is accomplished by closure of switches 22 and 24.
In the analog mode, an alternate pair of current sources 26 and 30 are energized to provide a nominal charging rate corresponding to an 800 microsecond pulse interval. A suitable analog such as the intracardiac electrogram derived from the pacemaker lead system is used to modulate one of the current sources 26 to vary the nominal charging rate in a positive or negative direction. This current modulation results in a varying pulse interval which corresponds to the amplitude variations of the intracardiac signal.
As shown in FIG. 3, digital data corresponding to a serial stream of logic one and logic zeroes is encoded by time periods between shorter and longer time period between bursts of radio frequency energy. It is important to note that the longer interval of 1,000 microseconds is not an even multiple of the shorter time period of 667 microseconds used to encode a logic zero. This scheme results in a lower error rate than systems wherein the logic zero and logic one are related as integer multiples. As shown in the lower analog traces of FIG. 3, a nominal time period of 800 microseconds corresponds to the zero level of the analog signal to be transmitted. Positive and negative excursions indicated by the phantom wave traces are used to encode the minimum and maximum excursions about the nominal value.
Although the telemetry system has been described with reference to only a single analog channel, it should be clear that a time division multiplexing scheme could be employed to simultaneously transmit more than one channel of analog data 36 as shown in FIG. 1. The sequential transfer of more than one analog channel is desirable for use with dual chamber pacemakers whose performance depends upon intrinsic atrial and ventricular electrograms. One possible scheme for achieving this time division multiplexing is using a multiplexer 35, shown in FIG. 2 wherein an additional analog channel, labeled "Analog B", is encoded by activating both current sources 28 and 26.
In a similar fashion, other analog signal sources 36 such as lead impedance or battery voltage could be suitably buffered and applied to variable current source 26 to establish a charging rate proportional to the analog signal.
Control Logic and Current Sources
The block diagram of FIG. 1 shows the two constant current sources 28 and 30 and one variable current sources 26 energized by suitable switching means interfaced to control logic 38. In practice, the switching and current sourcing function may be combined by the use of bipolar transistors which have a characteristic collector-emitter current which corresponds to the magnitude of injected base current. One suitable bipolar implementation for these current sources is shown in FIG. 4. Referring now to FIG. 4 the operation of this circuit is initiated by a reed switch closure connecting node 100 to the positive supply voltage. This connection supplies bias current to transistors 102, 104, 106, 108 which, in turn, supply bias current to transistors 110, 111, 112, 113, 114, 116, 118, 120 and to transistors 122, 124 and 126. Input node 99 interfaces the current source system with the sources of digital and analog data. This node 99 is connected to the positive supply voltage through a tri-state buffer when a logic "zero" is to be transmitted. The node 99 is connected to ground through the tri-state buffer for the transmission of "analog" information. The node 99 is disconnected and is floating when the tri-state buffer is in the high impedance configuration for the transmission of a logic "one".
For the transmission of a logic "one", transistor 118 is off and transistor 120 supplies approximately 225 nanoamps of current to the junction of the base of transistor 128 and the VFO capacitor 32. Assuming that capacitor 32 is near ground potential, then transistors 129, 130, 132, 134 and 136 are off. The voltage on capacitor 32 increases because of the charging current supplied by transistor 120 until the base of transistors 128 and 129 are equal. This allows current flow in transistors 129 and 138. When the collector-emitter current of transistor 129 exceeds the current flow through transistor 138, excess current flows into transistor 134, which turns it on. This, in turn, turns on transistor 136 which sinks current through the tank circuit 14 and causes the emission of a pulse of radio frequency. The circuit formed by transistors 130, and 134 form a latch arrangement which will not change state until the capacitor 32 discharges to approximately 0.5 volt whereupon these transistors shut off. The discharge of capacitor 32 takes approximately 2 microseconds and determines the time transistor 136 is on, which determines the width of the pulse applied to the tank circuit. When capacitor 32 is discharged, transistor 129 is off and transistor 128 is on which permits the cycle to begin again.
When a logic "one" is applied to input node 99, transistor 118 is activated which adds additional current to the VFO input node 18, shortening the time required to reach the trip level of the VFO circuit, thus shortening the pulse interval time to approximately 667 microseconds.
When input node 99 is grounded through the operation control logic, the analog transmission mode is enabled and an analog voltage signal applied to the base of transistor 142 is converted to a proportional charging current by transistors 142, 144, 146, 148, 140. As the analog voltage varies, the current of transistor 148 is modulated and the result of pulse interval is shifted with respect to the nominal 800 microsecond pulse interval.
Although the current sources and VFO have been shown implemented in bipolar technology, it should be appreciated tht equivalent structures exist in other technologies including metal oxide semiconductor technologies, and that other modifications may be made without departing from the scope of the invention. | A data telemetry system for use with implanted medical devices for transmitting digital and analog data to a remote receiver by enabling different combinations of fixed and variable value current sources according to a telemetry logic code to energize a tank coil and produce a ringing type of variable frequency RF signal. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority benefit of Taiwan application serial no. 89106159, filed Apr. 1, 2000. This application also provides prior art reference U.S. Pat. No. 5,923,654.
BACKGROUND OF THE INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to a network switch. More particularly, the present invention relates to a switch controller capable of easing flow congestion in a network.
[0004] 2. Description of Related Art
[0005] Ethernet is probably the most widely used local area network (LAN) in electronic communication. However, due to a data transmission rate of mere 10 Mbps, a conventional Ethernet can hardly transmit the vast quantity of data flow required in a multi-media system. Consequently, a faster Ethernet system having a data transmission rate of 100 Mbps called Fast Ethernet appears. In the Fast Ethernet design, a reconciliation sublayer is introduced between a medium access control (MAC) sublayer and a physical medium dependency (PMD) sublayer. To use the Fast Ethernet system, the network interface card in each network workstation has to be replaced by a 100 Mbps fast Ethernet interface card. The network interface card in each workstation can also be retained, however, a switch device must be employed. In fact, in order to retain the original network interface card in each workstation, the 10 Mbps Ethernet equipment formerly invested by a company can be incorporated into the Fast Ethernet network through the switch device.
[0006] A workstation with a conventional Ethernet utilizing a twisted pair, disregarding whether the data transmission rate is 10 Mbps or 100 Mbps, is connected to a server via an Ethernet hub. In general, the bandwidth of an Ethernet hub is normally shared by all the workstations connected to the network. For example, for a 16 port 100 Mbps Ethernet hub, if four workstations are connected to the network, the bandwidth is shared between four workstations. On the other hand, if each of the 16 ports is connected to a workstation, the bandwidth is shared between all sixteen workstations. As the number of network user increases, the number of collisions in the network increases proportionately. Hence, network bandwidth for each user decreases while users increase. In a multimedia-craved world, a conventional Ethernet hub can not meet the traffic demanded by booming users.
[0007] The switch device intends to improve data flow so that each of the workstations connected to the device is able to enjoy faster data transmission. To achieve correct data switching, the switch device must register various connections between each workstation and each port. In other words, the switch device must have a module for recording all the addresses in a way similar to a bridging device. When the switch device receives a frame, the device will consult a path lookup table to find the port of the target workstation. If the target workstation is found, a controller will send out a control signal to the switch element and redirecting the frame to the port. On the contrary, if the target workstation is not found, the frame is broadcast to all the ports just to ensure that the target workstation is able to receive this frame.
[0008] The institute of electrical & electronics engineering (IEEE) has recently provided a standard specification 802.3u for network management 802.3u capable of simplifying network management. The IEEE standard 802.3u introduces an ‘auto-negotiation’ function, also known as an N-way function. The ‘auto-negotiation’ function enables the switch device and the Ethernet interface card of a workstation to learn each others' state, which may have various combinations as shown in Table I. An N-way switch device can learn the data transmission rate (10 Mbps or 100 Mbps) and multiplexing mode (full duplex or half-duplex) for each Ethernet interface card to employ a proper congestion control mechanism.
[0009] Before ‘auto-negotiation’ strategy is incorporated into standard specification 802.3u of IEEE, a few manufacturers has already produced Ethernet card that has auto-sensing capability. A number of switch devices and Ethernet cards are shown in Table 1, some of the devices has auto-negotiation functions while some has not.
TABLE 1 various combinations of states between an Ethernet hub (switch device) and Ethernet card with or without ‘auto-negotiation’ like function and operation thereof. New generation New generation of auto- Support only 10/100TX co- negotiation 10 BASE-T Support only existent network 10/100TX co- hub (switch 100BASE-T hub and hub (switch existent hub device) (switch device) device) (switch device) Support only 10 Mbps Change to a 100 Manual switch of Automatic 10BASE-T Mbps network the hub (switch switching of network card card device) to 10 hub (switch Mbps device) to 10 Mbps Network Automatic Automatic switch Automatic switch Manual switch card with switch of of network card to of network card to of hub (switchi non-standard network card 100 Mbps 100 Mbps after device) and auto-sensing to 10 Mbps manual switch of network card to capability hub (switch 100 Mbps device) to 100 Mbps 10/100TX Automatic Automatic switch Manual switch of Automatic co-existent switch of of network card to hub (switch switch of hub network card network card 100 Mbps device) and (switch device) with new to 10 Mbps network card to and network generation half-duplex 100 Bbps card to 100 auto- Mbps negotiation capability
[0010] Due to the rapid progress in semiconductor technologies, the difference in the cost of producing a switch device and an Ethernet hub is getting smaller. Because of many advantages of a switch device, Ethernet hubs are gradually replaced by switch devices. Moreover, since a switch device can perform the functions provided by an Ethernet hub, combinations of devices detailed in Table 1 are all applicable to switch devices.
[0011] Furthermore, due to the multiplicity of transmission modes among different Ethernet devices, the automatic-negotiation relies on a set of priority sequence registered in a table to ensure the selection of an optimal transmission mode between two Ethernet devices. For example, a 10/100 Mbps dual speed network card is capable of operating at 10 Mbps or 100 Mbps. Under the priority algorithm, the priority sequence table preferably selects 100 Mbps. Table 2 is a priority setting for the different transmission modes for Ethernet devices having auto-negotiation capability.
TABLE 2 Priority setting of Ethernet devices with auto-negotiation capability Priority Explanations 1 100BASE-T2 full duplex 2 100BASE-T2 3 100BASE-TX full duplex 4 100BASE-T4 5 100BASE-TX 6 10BASE-T full duplex 7 10BASE-T
[0012] In Table 2, full duplex transmission mode has a higher priority than half-duplex mode because full duplex has a much higher data transmission rate than half-duplex. Transmission mode 10BASE-T has the least priority because it has the slowest data transmission rate. By consulting the priority table 2, the most suitable mode for transmitting data between the switch device (hub) and the network card can be selected.
[0013] To increase the overall throughput after the best transmission mode is chosen, the switch device usually provides a congestion control mechanism for transmitting information packets among the transmission ports. According to the resulting auto-negotiation between the target device (for example, an network card) and the switch device, one of the following three congestion control modes are adopted: (1) When the target device has full-duplex transmission capacity and flow control capability, the switch device will opt for a flow control mode; (2) when the target device has full-duplex transmission capacity but no flow control capability, the switch device will opt for a drop control mode; and (3) when the target device has neither half-duplex transmission capacity nor flow control capability, the switch device will opt for a back-pressure control mode. In the backpressure control mode, the switch controller issues a collision signal to destroy an incoming packet. On detecting the collision, the workstation will branch into a binary exponential backoff algorithm to compute a waiting time before the packet is submitted again. In the drop control mode, the packet is directly dropped at the source port instead of sending to the congested target port. This is because the target device uses full duplex transmission and different transmission lines are used respectively for sending and receiving data. Further, the source port enters a flow control mode whenever the target port is congested. In subsequent stage, flow control windows (XOFF windows) are triggered. Once XOFF windows are triggered, the switch controller will control the flow of packets according to the number of free buffers present.
[0014] The congestion control method in a conventional switch controller has the following two drawbacks:
[0015] (1) The ports of a switch controller have a plurality of input buffers. Furthermore, a plurality of private buffers are reserved by the input terminals of the ports for private use. However, when the number of free output buffers in the port of the switch controller is insufficient, the deployment of buffers by other ports is not permitted. Hence, the capacity of the switch device is limited.
[0016] (2) The XOFF threshold value of the flow control window is fixed. Hence, the switch device is unable to adjust the XOFF threshold value dynamically according to the number of free buffers. Therefore, the management of shared memory in the switch controller can not achieve the best performance.
[0017] [0017]FIG. 1 is a block diagram showing the electrical connections in a conventional switch device. The switch device 100 in FIG. 1 has a plurality of ports (eight ports are shown in FIG. 1). Each port is connected to a physical layer device 130 . A static random access memory (SRAM) 120 is provided in the Ethernet control device 110 serving as a shared memory or buffer. On receiving a network packet, the port transfers and stores the packet in the shared buffer until the packet is retrieved by a target port.
[0018] [0018]FIG. 2 is a diagram showing the congestion control mechanism for resolving congestion in a conventional switch controller. When both the switch device and the network card can operate in full duplex mode and have flow control capability, flow control mode is called upon to resolve network congestion problems. While testing the performance of switch controller, there is an item known as head of line blocking (HOL). As shown in FIG. 2, head of line blocking refers to the blocking of the output of a port in the switch controller due to occupation so that other ports is unable to function normally. For example, assume that all ports are capable of transmitting data at 100 Mbps. When port 2 transmits data at 100% bandwidth to the port 3 while port 0 also transmits data at 50% bandwidth to the port 3 , the total amount of data transmitted to port 3 is 150 Mbps. Hence, the amount of data going to the port 3 exceeds its admissible limit. Consequently, some packets may accumulate in the output queues of the port 3 . In the meantime, if the port 4 needs to transmit data at 100% bandwidth to port 5 , the transmission fails because all the free buffers are occupied due to the heavy congestion at port 3 . Therefore, head of line blocking is a major factor affecting the efficiency of the switch controller.
[0019] In this invention, a number of private buffers are reserved for each port. Thus, although the port 3 is heavily congested, data transmission between port 4 and port 5 can still carry on because the port 5 has private buffer space.
SUMMARY OF THE INVENTION
[0020] Accordingly, the object of the present invention is to provide a switch device and a method for easing congestion in a data transmission network by assigning a number of private buffers to the output terminals of ports of a switch controller. In other words, a number of private buffers (for example, four private buffers) are retained by each port while the rest of the buffers are shared by all the ports. The number of reserved buffers is related to the size of static random access memory used by the switch device so that the disadvantage of a conventional device is prevented.
[0021] A second object of this invention is to provide a switch device and a method for easing congestion in a data transmission network by making the triggered flow control window threshold (XOFF threshold) value of a switch controller adaptive to demand. The switch controller is capable of adjusting the value of the triggered XOFF threshold dynamically according to the number of free buffers present. Hence, the shared memory inside the switch controller can be utilized optimally and the drawbacks of a conventional device can be removed.
[0022] To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a switch controller inside a switch device capable of easing network congestion, the switch controller has a plurality of ports and the switch device further includes a shared buffer and a plurality of physical layer devices (PHY), the shared buffer can be divided into a plurality of buffering units. The switch controller comprises a buffer control device, a plurality of port control devices, a forwarding control device, and a queue control device. The buffer control device is coupled to the shared buffer for assigning and releasing the buffering units. The plurality of port control devices are coupled to the physical layer devices and the buffer control device, in which each port control device has a one-to-one correspondence with the ports, the port control device that corresponds to a source port receives a network packet and then sends the packet to at least one of the buffering unit(s) for storage. The forwarding control device is coupled to the port control devices, and a target port of the packet is determined according to a header of the network packet. The queue control device is coupled to the port control devices and the buffer control device, wherein the queue control device further includes a plurality of output queues, each output queue has a one-to-one correspondence with the port control devices, each output queue has a number of reserved buffering units, and the buffering units for storing the packets are linked to the output queue corresponding to the port control device at a target port. The source port triggers or terminates a congestion mode to control the number of free buffering units in response to the number of reserved buffering units in the output queue.
[0023] To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention further provides a method for easing data transmission congestion in a switch device having a plurality of ports. The switch device includes a shared buffer capable of dividing into a plurality of buffering units. The method comprises the steps as follows. A plurality of output queues are provided, in which the output queues have a one-to-one correspondence with the ports, and each output queue has a number of reserved buffering units. The buffering unit(s) are then assigned in the shared buffer. A packet is received from a source port and storing the packet in an assigned buffering unit. The target port of a packet is determined according to a header of the packet. Then, the buffering unit containing the packet is linked to the output queue that corresponds to the target port. The free buffering units are thus controlled according to a number of reserved buffering units in the output queue and a triggering or a terminating condition of the source port.
[0024] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
[0026] [0026]FIG. 1 is a block diagram showing the electrical connections in a conventional switch device;
[0027] [0027]FIG. 2 is a diagram showing the congestion control method for resolving terminal congestion in a conventional switch controller;
[0028] [0028]FIG. 3 is a diagram showing the connectivity of private output queues for controlling data congestion in an switch controller according to this invention;
[0029] [0029]FIG. 4 is a diagram showing the use of XON-XOFF window to control congestion in an switch controller;
[0030] [0030]FIG. 5 is graph showing the relationship between the number of free buffers and the triggering of the XON/XOFF windows in the congestion control method used in the switch controller according to this invention;
[0031] [0031]FIG. 6 is a diagram showing the relaxation of the conditions of other ports to trigger the XOFF window after one of the ports has already been triggered and the concurrent shutting of all the XOFF windows of ports in the end for the congestion control method used in the switch controller according to this invention;
[0032] [0032]FIG. 7 is a block diagram showing the connection of the switch controller of the switch device according to this invention;
[0033] [0033]FIG. 8 is a block diagram showing the electrical connection of the switch controller according to this invention; and
[0034] [0034]FIG. 9 is a block diagram showing the port control device of a switch controller according to this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0035] Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
[0036] switchFIG. 3 is a diagram showing the connectivity of private output queues for controlling data congestion in a switch controller according to this invention. Each port of the switch controller of this invention has a private output queue. When a packet is received from one of the ports, the packet is sent to the private output queue. As shown in FIG. 3, the largest packet Ethernet capable of receiving is usually 1518 bytes (not including preamble and SFD columns). Hence, each buffer must have a size of at least 1.5 KB. To request a buffer space, a signal is sent to a buffer control device so that a buffer is linked to the output queue. After the packet is forwarded and the storage space is emptied, linkage between the queue and the buffer is released and the associated buffer becomes free. For example, the queue in FIG. 3 is linked to four buffers.
[0037] [0037]FIG. 4 is a diagram showing the use of XON-XOFF window to control congestion in a switch controller. As shown in FIG. 4, in the absence of flow congestion in a switch controller, every ports can transmit packets normally. On the other hand, when a particular port experiences congestion, the switch controller will carry out congestion control according to the result of auto-negotiation. If backpressure control mode is employed, the switch controller will issue a jam signal to destroy the packet. On sensing the jam signal, the workstation will branch off into a binary exponential backoff algorithm to find out waiting period before re-transmission. If the drop control method is employed, since signal transmission and reception are respectively on different transmission lines, jam signals cannot be employed to remove the packet. The packet can only be dropped at the switch controller so that the packet will not be transferred to the target port. If both the switch controller and the network card of the workstation are full duplex and have flow control capability, then flow control mode is used. As shown in FIG. 4, when the target port of the packet is congested, the source port will step into a XOFF window. The source port is now under flow control. After stepping into the XOFF window, any incoming packets from the source port of the switch controller are managed according to the number of free buffers. In other words, the bulk of traffic is controlled by the source port. The control remains in the XOFF window until the number of free buffers is returned to a level suitable for executing normal data transmission to or from the target port. Under such circumstances, the XOFF window is released so that control is returned back to XON.
[0038] In this invention, flow control is based on the XON/XOFF windows. In the XON window, the source port is not in a congested state. Hence, any incoming packet can be transmitted normally. If an incoming packet exceeds the limit imposed by the congestion controll, congestion control will jump to the XOFF window after the packet is transferred from the source port to the output queue of the target port. In the XOFF window, the source port is in a congestion control state. Consequently, any incoming packet will trigger a congestion control operation according to the selected strategies. FIG. 8 is a block diagram showing the block diagram of the switch controller according to this invention. As shown in FIG. 8, the drop control mechanism under the condition of DROP_EN=1 used in the forwarding control device 111 is based on the congestion window of each port. The congestion window is defined under the following conditions: (1) any one of the port in the XOFF window, or (2) one target port steps into the XOFF window if the number of reserved buffer is zero. The decision to enable the XON/XOFF window and DROP terminal is provided by the transmission medium access control (TMAC) device of the switch controller 110 according to the state of the port and the plurality of management signals input from the queue control device 113 .
[0039] In the XOFF window, the related congestion control operations includes: (1) Flow control operation: A packet is output to the output queue by unicasting or broadcasting. If the limit imposed by the congestion control is exceeded, the queue control device 113 will generate a triggering signal to trigger the transmission medium access control (TMAC) device of the source port, so that a pause time (for example, FFFFH) flow control frame is transmitted. The following two conditions will lead to the congestion control: (i) φ<=max{Ψ, 28} and R[k]=0, where φ represents the number of free buffers, Ψ represents the total number of reserved buffers in all the ports,
Ψ = ∑ k = 0 9 R [ k ] .
[0040] R[k] represents the number of reserved buffers in the k th port. (ii) Any one of the ports is already in XOFF and R[k]=0. The theory is explained in detail using FIG. 5. As a particular source port is in the XOFF window, a XOFF triggering signal will still be emitted from the queue control device 113 so that the TMAC device 1144 will send out a pause time (for example, FFFFH) flow control frame. Although this may lead to using a wider bandwidth in executing flow control operation, repetitive transmission promises the successful reception of the XOFF flow control frame. (2) Back pressure control of half-duplex port: when a non-local packet is received, the input control device 1141 will generate a non-local signal to inform the TMAC device 1144 . If the TMAC device 1144 is in the XOFF window and the port is half-duplex, the TMAC device 1144 will destroy the packet. (3) Drop control of the reserved private buffers: when an incoming packet is coming from a source port already in DROP_ON window and the target port is already in the congestion control window, the packet can be detected by forwarding control device 111 during a lookup operation. The forwarding control device 111 then masks the port so that the input control device 1141 is able to drop the packet. Note that the DROP_ON window guides the specified port to enable the drop function within a given time period so that the DROP_ON window is determined by the TMAC device. When any one of the ports is already in the XOFF window and that R[k]=0, the queue control device 113 will decide to turn on the congestion control window of the k th port.
[0041] [0041]FIG. 5 shows the relationship between the number of free buffers and the triggering of the XON/XOFF windows in the congestion control mechanism used in the switch controller according to this invention. As shown in FIG. 5, the number of free buffers can vary, for example, between 64 to 661, which depends on the type of memory used. XON threshold value represents the point of decision by the switch controller whether to terminate the flow control or not. The threshold value can be programmed but is fixed once the programming is completed. In other words, the XON threshold value is an unchangeable constant after programming. The threshold value is about half of the free buffers minus ten. When the number of free buffers is smaller than the XOFF threshold value, the switch controller will step into the flow control window to execute flow control operation. Flow control operation will immediately start after going into the flow control window. Because the packets accumulated in the output queue need to send out, the number of free buffers will continue to decrease. Sometimes, all the virtual free buffers are used up. When the virtual free buffers are all used up, the number of reserved buffer in each port is zero. Although new packets are still accepted, flow control is triggered to limit the process. When the virtual free buffers are all used up, all incoming packets are dropped off. The purpose of establishing an XOFF threshold value is: (1) to prevent a few ports that demand large quantities of buffers from exhausting traffic resource . Hence, the XOFF threshold value must be greater than or equal to the total number of reserved buffers. (2) To prevent from dropping packets due to insufficient free buffers and a slow response. In this embodiment, the flow control response time of each port is two buffers. The XOFF threshold value is adaptive. That means, the XOFF threshold value can be adjusted according to the number of reserved buffers demanded so that the system is more flexible. The threshold value can be determined using the parameters including:
[0042] Q[k]: queue length of the k th output port;
[0043] R max : the greatest number of reserved buffers in each port;
[0044] R[k]: the number of reserved buffers in the k th port;
[0045] Ψ: the total number of reserved buffers,
Ψ = ∑ k = 0 9 R [ k ] ;
[0046] Φ: the number of free buffers;
[0047] C: the number of reserved buffers in the virtual free space, C=10 (preset value);
[0048] Ω: the number of virtual free buffers,
[0049] when Φ<=C, Ω=0, and when Φ>C, Ω=Φ−C;
[0050] Θ: XON threshold value
[0051] Step into the XOFF window if (Ω=0),
[0052] (Ω<=max {Ψ, 28} and R[k]=0),
[0053] or (any port already in the XOFF window and R[k]=0).
[0054] Any input port steps out of the XOFF window if (Ω>Θ).
[0055] Amongst the parameters listed, Q[k] represents queue length of the k th output port. R max represents the greatest number of reserved buffers in each port. Ψ represents the total number of reserved buffers from port 0 to port 9 ,
Ψ = ∑ k = 0 9 R [ k ] . R [ k ]
[0056] represents the number of reserved buffers in the k th port. Φ represents the number of free buffers. C represents the number of reserved buffers in the virtual free space, for example 10. Ω represents the number of virtual free buffers. When Φ<=C, Ω=0. When Φ>C, Ω=Φ−C. Θ represents XON threshold value. For example, Q[k=3]=3 indicates the length of the third port is 3. R max is 4. R[k]=4−3 =1 indicates that three of the four reserved buffers are used. If the number of reserved buffers in each port is 2, then
Ψ = ∑ k = 0 9 R [ k ] = 20.
[0057] Φ=22 indicates the number of free buffers is 22. C represents the number of reserved buffers in the virtual free space, i.e., a preset response time. C is set to a value of 10, and the value of XOFF threshold value must be greater than C. Ω represents the number of virtual free buffers and the value is Φ−C=22−10=12. In other words, the number of free buffers appears to be 12 but the number of free buffers is actually 22 so that the exhaustion of buffers is prevented.
[0058] In general, when the following three conditions are met, the switch controller will step into the XOFF window: (1) Ω=0 indicates no virtual free buffers is available, and hence the port must step into the XOFF window to execute flow control; or (2) Ω<=max {Ψ, 28} and R[k]=0, for example Ψ=20, indicates the number of virtual free buffer <=28 or Ψ, and the number of reserved buffers in the target port is zero; or (3) any port already in the XOFF window and R[k]=0, indicates at least one of the ports has stepped into the XOFF window, so the conditions for stepping into the XOFF window is relaxed. Furthermore, the number of reserved buffers in the target port is zero so that the source port will step into the XOFF window. As long as one of the three aforementioned conditions is met, the source port will step into the XOFF window. Hence, the source port is prevented from sending any more packets so that the target port is able to step out from the XOFF window earlier. As soon as the number of virtual free buffers is greater than the XON threshold value, all the port already in the XOFF window will simultaneously jump out from the XOFF window. Hence, the normal transmission is resumed.
[0059] [0059]FIG. 6 is a diagram showing the relaxation of the conditions of other ports to trigger the XOFF window after one of the ports has already been triggered and the concurrent shutting of all the XOFF windows of ports in the end for the congestion control mechanism used in the switch controller according to this invention. As shown in FIG. 6, flow control operation is being conducted as soon as the second port steps into the XOFF window. To prevent the continued deterioration of congestion, conditions for other ports to step into the XOFF window is relaxed, such as sending a packet from port 6 to port 7 . Since the number of reserved buffer for port 7 is zero and port 2 is already in the XOFF window, the port 7 also steps into XOFF window to carry out flow control. When the number of free buffers is greater than the XON threshold value, all the ports jump away from the XOFF window concurrently and releasing flow control at the same time.
[0060] [0060]FIG. 7 is a block diagram showing the connection of the switch controller of the Ethernet switching device according to this invention. As shown in FIG. 7, the Ethernet switching device 100 includes an switch controller 110 , a static random access memory unit 120 , a plurality of physical layer devices 130 , an electrical erasable programmable read only memory (EEPROM) 140 and a central processing unit (CPU 150 ). Size of the static random access memory unit 120 may be determined by the jumpers. The controller 110 is coupled to the CPU 150 port via a medium independent interface (MII). The controller 100 has a CPU port that couples with another CPU 150 port via an ISA/IDE interface line. In the meantime, the controller 110 is connected to a plurality of physical layer devices 130 through a reduced medium independent interface (RMII). RMII reduces pin out number so that the 14 pins of the MII can be reduced to just six.
[0061] [0061]FIG. 8 is a block diagram showing the electrical connection of the switch controller according to this invention. As shown in FIG. 8, the switch controller 110 includes a plurality of port control devices 114 , a queue control device 113 , a forwarding control device 111 and a buffer control device 112 . The plurality of port control device 114 are coupled to the plurality of physical layer devices (PHY) 130 and a plurality of external signals. Through these physical layer devices 130 , a plurality of state signals is received from the connection devices on the other end. These state signals include duplex mode and flow control capability signals. According to the flow control enable (Flow_Control_En) signal, the drop control enable (Drop_Control_En) signal and the backpressure enable (Backpressure_En) signal, the congestion control mechanism used by the switch controller 110 is selected. The flow control enable signal, the backpressure enable signal and the drop control enable signal can be determined by jumpers. The plurality of state signals generates a plurality of flow control window (XOFF_Window[9:0]) signals to the queue control device 113 . According to the flow control window (XOFF_Window[9:0]) signals and the external signals, the selection of drop control is decided whether the drop-triggering signal DROP_ON[9:0] should be enabled.
[0062] The forwarding control device 111 is coupled to the plurality of port control devices 114 . According to the heading of packet received by the plurality of port control devices 114 , a table lookup is carried out to determine the address of the target port for a packet. The buffer control device 112 is coupled to the plurality of port control devices 114 . Each port control device 114 has been assigned a number of private buffers in the shared buffer 120 . The number of private buffers can be assigned by the EEPROM 140 or the CPU 150 . According to the requests by the plurality of port control devices 114 , the buffer control device 112 assigns or releases the private buffers.
[0063] The queue control device 113 is coupled to the plurality of port control devices 114 , the buffer control device 112 and the forwarding control device 111 . Each port control device 114 has a corresponding output queue in the queue control device 113 . According to the requests from the various port control devices 114 , the queue control device 113 establishes links in the output queues. The congestion control mechanism selected by each of the port control device 114 is activated according to the plurality of window flow control signals and the lengths of the plurality of the output queue. For example, if the output queues in the queue control device 113 experience congestion, a congestion triggering (CONGEST_ON) signal is transmitted to the forwarding control device 111 and the flow control window [9:0] signal is also triggered to request flow control of the source port.
[0064] [0064]FIG. 9 is a block diagram showing the port control device of an switch controller according to this invention. Each port control device 114 includes a receive medium access control (RMAC) device 1142 , an input control device 1141 , an output control device 1143 , a transmission medium access control (TMAC) device 1144 and a physical layer control (PHY control) device 1145 . The RMAC device 1142 is coupled to one of the physical layer device 130 . On receiving a network packet, the RMAC device 1142 inspects the packet for any errors. If no errors are found, the packet is received, otherwise the packet is returned. The input control device 1141 is coupled to the RMAC device 1142 , the queue control device 113 and the buffer control device 112 . According to the network packet and the request for private buffer assignment to the buffer control device 112 , the input control device 1141 signals the queue control device 113 to request queuing to the output queues. The output control device 1143 is coupled to the queue control device 113 and the buffer control device 112 for outputting packets from the output queues and releasing the free buffers to the buffer control device 112 thereafter. The TMAC device 1144 is coupled to the output control device 1143 and one of the physical layer devices 130 . According to the plurality of window flow control (XOFF_Window[9:0]) signals and the plurality of external signals, a DROP_ON signal to the forwarding control device 111 can be asserted so as to drop the packet. The physical layer control device 1145 is coupled to the TMAC device 1144 and one of the physical layer devices 130 . According to the plurality of state signals, the physical layer control device 1145 is able to send out a flow control enable (FC_EN) signal to the TMAC device 1144 .
[0065] This invention also provides a method for resolving network congestion problems. The method relies on a plurality of external signals, a plurality of state signals and a plurality of congestion control mechanism.
[0066] A plurality of packets are received from network and then sent to the plurality of port control devices 114 . According to the plurality of external signals, the plurality of state signals, the port control devices 114 generate a plurality of flow control window signals. The plurality of packets are passed into the forwarding control device 111 where the target port of each packet can be found in a look-up table. If the target port is already in a congested state and the source port where the packet comes from has no flow control capability, the packet is dropped. On the other hand, if the target port has not yet stepped into the congested state, a request for assigning private buffers from the shared buffer 120 is issued to the output queue, corresponding to the target port in the queue control device 113 . Furthermore, according to the plurality of window control flow (XOFF_Window[9:0]) signals and lengths of the plurality of output queues, the congestion control mechanism in each port control device 114 is selected.
[0067] In this embodiment, each port has an output queue. According to the size of the packet, a signal requesting output buffers is sent by the input device. After the packet is transmitted, the buffers are is released back to the output queue. In addition, each port has private output buffers. These private output buffers are located at the output terminals of the port. The private output buffers are shared by each port so that the management of ports is more flexible. Furthermore, these output private buffers and the shared buffers 120 are size related. When the shared buffers 120 have a larger capacity (for example, 64 KB×64), the private output buffers can be set to a higher value. On the other hand, if the shared buffers 120 have a smaller capacity (for example, 64 KB×32) the private output buffers can be set to a smaller value.
[0068] The plurality of external signals include flow control enable signal, drop control enable signal and backpressure enable signal. The values of the flow control enable signal, the backpressure enable signal and the drop enable signal are determined by jumpers. The plurality of state signals includes full duplex mode signal and flow control capability signal. The flow control further includes a flow control frame. The frame includes a 16-bit pause time. When the flow control window is triggered, the 16-bit pause time has a value of FFFFH. Alternatively, when the flow control window is shut, the 16-bit pause time has a value 0000H. The flow control window can be triggered under the following conditions:
[0069] (1) if the number of virtual free buffer in the shared buffer 120 is zero; or
[0070] (2) if the number of virtual free buffer is smaller than or equal to the largest value between the total reserved value and 28, and the number of reserved buffers in the target port control device for a particular packet is also zero; or
[0071] (3) if one of the port control devices has already triggered the flow control window and the number of reserved buffer in the target port of a particular packet is zero.
[0072] Wherein the number of virtual free buffer is the number of free buffers in the shared buffer 120 minus the number of reserved buffers. For example, ten reserved buffers are pre-assigned.
[0073] The flow control window includes a shut flow control window threshold value, XON. When the number of free buffers is greater than the XON threshold value, the flow control window is shut. The value of the XON threshold can be set through the externally connected EEPROM 140 or the CPU 150 . The value is about half of the shared buffer 120 . Capacity of the shared buffer 120 is generally determined by the size of the static random access memory (SRAM) unit. Furthermore, capacity of the SRAM can be obtained through jumper setting. For example, capacity of the SRAM unit can be 32 KB×32 or 64 KB×32. The number of private buffers inside the shared buffer 120 can also be assigned by the externally connected EEPROM 140 or CPU 150 .
[0074] The flow control mode further includes a triggering flow control window threshold value, XOFF and XOFF thresholds are adjustable. The value of XOFF threshold is the larger value between the total reserved quantity and the value 28. The total reserved quantity is the sum of the reserved quantity in each port. Since the reserved quantity is a variable, the triggering flow control window threshold value (XOFF threshold) is 28 when the total reserved quantity is smaller than 28. On the other hand, if the total reserved quantity is greater than 28, the reserved quantity is retained to serve as a threshold value. Hence, flexibility is increased.
[0075] In summary, this invention provides a method for easing network congestion. The present invention provides at least the following advantages:
[0076] (1) By flexibly adjusting the number of reserved buffers, XOFF threshold value is variable. Hence, throughput of the transmission system can be optimized.
[0077] (2) By reserving a number of private buffers at the terminal of the port in a switch and allowing each port to share all the buffers, all the buffers are fully utilized.
[0078] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents. | A method for easing data transmission congestion in a switch device having a plurality of ports. The switch device includes a shared buffer capable of dividing into a plurality of buffering units. The method comprises the steps as follows. A plurality of output queues are provided, in which the output queues have a one-to-one correspondence with the ports, and each output queue has a number of reserved buffering units. The buffering unit(s) are then assigned in the shared buffer. A packet is received from a source port and storing the packet in an assigned buffering unit. The target port of a packet is determined according to a header of the packet. Then, the buffering unit containing the packet is linked to the output queue that corresponds to the target port. The free buffering units are thus controlled according to a number of reserved buffering units in the output queue and a triggering or a terminating condition of the source port. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to the problem of deploying network electronic products within an existing networked environment without requiring configuration input from the end user. Additionally, the present invention relates to the problem of deploying network electronic devices within an existing networked environment having a network access device that may limit or restrict the connection of a Local Area Network (LAN) to a Wide Area Network (WAN).
BACKGROUND TO THE INVENTION
[0002] In a basic home or business setup, an edge device on a LAN, that is a device at the edge of the LAN, for example a Personal Computer (PC), is connected to a WAN interface device. The WAN interface device may be in the form of a cable or Digital Subscriber Line (DSL) modem or router. The WAN interface device enables the connection of the LAN to a WAN such that the LAN edge device can communicate with devices on the WAN.
[0003] For the LAN edge device, or indeed any other intermediate or “embedded” LAN devices, to communicate with devices on the WAN, specifically the Internet, it must have the following information:
Its own Internet Protocol (IP) address The IP address of the WAN interface device to enable communication between the LAN device and the WAN interface device, termed gateway IP address The IP address of a Domain Name Server (DNS) to enable communication with “named” devices on the Internet
[0007] There are a number of protocols or mechanisms today that enable a LAN device to automatically acquire, or to be statically configured, with this information and also protocols or mechanisms that configure part of this information. Two mechanisms are commonly used today to determine the IP addresses. Dynamic Host Configuration Protocol (DHCP) is a client/server-based protocol for assigning IP addresses on an IP network automatically. Alternatively, the IP addresses can be manually or statically configured.
[0008] There are also a number of other mechanisms such as AutoIP that deal with the automatic assignment of IP addresses for the LAN device itself, but do not address the WAN interface device and Domain Name Server addressing.
[0009] Network Address Translation (NAT) is a mechanism that allows a single public IP address, i.e. an address unique within the Internet, to be shared by a plurality of LAN devices using private IP addresses, i.e. addresses not used to communicate directly with other devices on the Internet, in order for the LAN devices to communicate with devices on the Internet. With “full” NAT, a DSL modem, for example, will use a public IP address whilst a PC, for example, has a private IP address. No sharing of addresses occurs with full NAT. In simple deployment scenarios, and in particular Digital Subscriber Line deployments, it is common to use something termed “half-NAT”. Half-NAT enables a DSL modem, for example, and a single PC to share a common public IP address. This overcomes a problem in that NAT can cause problems since protocols that communicate over IP often embed logical IP address(es) of edge devices within the communication.
[0010] DSL deployments may use a variety of protocols to connect the WAN interface device to the WAN. A number of solutions exist to automatically determine which network protocol is used by the WAN. The WAN interface device, i.e. the gateway or router, is subsequently configured to use this protocol to automatically determine the network addressing required and to allow connection of the WAN interface device to the WAN.
[0011] Where a LAN device is an embedded/edge LAN device, such as an IP phone, it may function either as an edge LAN device or an embedded LAN device. As an embedded LAN device, it is connected between an edge LAN device and a WAN interface device, or directly to the Internet. Accordingly, the embedded/edge LAN device has both a WAN network port for connection to the WAN interface device, and a LAN network port for connection to the edge LAN device.
[0012] The DSL Forum (www.dslforum.org) provides protocols to configure the WAN and LAN network ports of embedded/edge LAN devices. This requires a specific protocol to be implemented by the device in order to be configured. However, such configuration does not take into account the existing network in which the device sits and will not work on networks other than those using DSL WAN interface devices. It is also a client-server based model and requires investment on the part of the service provider
[0013] It is common for many embedded/edge LAN devices that provide additional services to a LAN to have a plurality of LAN network ports to which a user can connect other LAN devices, such as networked PCs.
[0014] Some known WAN interface devices limit the number of LAN devices that can connect to a WAN via the WAN interface device. This is usually achieved by limiting the number of devices that can connect through the WAN interface device to services such as DHCP. This is often implemented by limiting access to the first Media Access Control (MAC) address seen on the LAN by the WAN interface device.
[0015] In these situations known embedded/edge LAN devices typically either ask the user what type of WAN interface device they are connected to and the MAC address of their PC, or require the user to purchase an additional “NAT-router” to connect the WAN and the LAN. The user will often have to configure this router with the MAC address of their PC or “power-cycle” the WAN interface device. In both cases the embedded/edge LAN devices will configure NAT. This could cause problems for the end user after the device is installed as some protocols may now cease to work.
[0016] A majority of end users are not familiar with terms such as “DHCP”, “IP address” and “MAC address” and hence many networked consumer electronic products are hard for users to “deploy” and start using. As mentioned above, known products require the end user to specifically configure certain modes of operation and typically only offer DHCP by default. Users often do not know details of particular WAN interface devices. Users also can become frustrated when networked devices, which were working perfectly well before, do not continue to work when they install new devices on the network, even more so when further hardware is necessary to correct such problems.
[0017] In addition end users are frequently confused by the installation of such devices and can inadvertently connect the WAN and LAN network ports to the incorrect networks, i.e. connecting the LAN port to the WAN, and the WAN port to the LAN. Currently available devices fail to operate in this circumstance. The known problems of communication over IP, such as voice-over IP (VoIP), and NAT, which many such devices default to, have yet to be adequately addressed.
[0018] This creates a significant support burden for operators deploying such devices and affects the take up of new technologies due to the complication and fear factor these devices create with end users.
SUMMARY OF THE INVENTION
[0019] According to a first aspect of the present invention, a method of self-configuration of a network device having at least one network connection port, comprises the steps of:
[0020] (i) after booting of the network device, actively probing a network in which the network device is located and analysing data packets received on the port(s);
[0021] (ii) attempting to determine a network configuration for all network connections the device can make according to information extracted from the received data packets; and
[0022] (iii) configuring device settings according to the network configuration determined.
[0023] The method in accordance with the first aspect of the present invention is advantageous in that it can eliminate end user configuration of the network device by automatically determining the setup of an existing, or new, networked environment in which the network device has been installed. Once sufficient information regarding the setup of the networked environment is known the network device can self-configure according to the network environment setup. In this manner a user need have no networking knowledge to properly install the network device, and may have the same experience before and after the device is connected to an existing networked environment.
[0024] In a preferred embodiment of the present invention, the network device is an edge device that does not perform the function of a router. The device settings to be self-configured include the local IP address to be assigned to the device from free IP addresses available on the local subnet at the device's location. In addition, the IP and MAC addresses of a gateway through which the device can connect to a WAN, and a DNS server address can be identified and self-configured so that the device can make connections to the Internet.
[0025] In the preferred embodiment the device further includes a storage device containing an executable code, wherein the device is adapted to execute the code to perform the method in accordance with the first aspect of the present invention. The storage device preferably contains a plurality of predetermined network setting types and by execution of the code one type of the network configuration may be selected from these predetermined types. Possible network configuration types include DHCP and DHCP where the number of physical devices on the LAN in which the device is located is limited by a network access device, so-called limited MAC DHCP. The self-configuration may alternatively include obtaining IP addresses based on the setup of local devices. In addition, the configuration may be semi-automatic, or even fully manual, where the information required for full self-configuration is not available to the device, or is not possible.
[0026] To enable self-configuration, the preferred device for implementing the method of the first aspect of the present invention should be resilient to such conditions as “incorrect” connection of network cables, the order in which other devices in the network environment are “powered-up”, and changes in the network environment. This resilience is provided in the form of a number of algorithms that may be included in the executable code such that the device can cope with many situations prior art devices cannot. For example, by identifying a gateway through which the device is connected to a WAN, the device port associated with the gateway can be determined. The device can therefore be configured according to the functionality of the port rather than the physical location of the port in the device.
[0027] The method may be adapted to execute a routine such that a case where a user incorrectly connects two ports of the device together in a “loop-back”, one or other or both of the ports so connected is automatically disabled.
[0028] The method may be further adapted to build up a database of information related to the network environment. In this way, the order in which the device and other devices in the network environment are “powered-up” becomes of little relevance in the method of the first aspect of the present invention. This database may be stored, for example in a storage device, for later interrogation in the self-configuration routine, or the information therein may be used in the device configuration “on-the-fly”.
[0029] As the network environment of the device changes, for example, as other devices are added or removed, network addresses become available or are taken up, and devices are powered on and off, one or more of the steps of the method of the first aspect of the present invention may be started, paused, stopped and/or restarted as necessary to ensure the device remains correctly configured, automatically where possible.
[0030] To build the database of information related to the network environment identified above, the method of the first aspect of the present invention could include steps of identifying and analysing packets received on the device ports. This packet analysis could retrieve information from packet headers relating to source and destination IP and MAC addresses, for example, to be used to determine the presence and status of particular devices in the network such as a DNS server, gateway, modem, router or PC.
[0031] Once a successful device configuration has been established; this configuration may be stored in the method of the first aspect of the present invention such that it is saved over a hard reset of the network device. This saved configuration may then be subsequently tested as a potential shortcut to full re-configuration of the device.
[0032] According to a second aspect of the present invention, a method of determining port connectivity for a network device having at least two network connection ports, wherein one of the ports is connected to a WAN, comprises the steps of:
[0033] identifying a gateway through which the device is connected to the WAN; and
[0034] determining through which of the ports information is conveyed to and from the gateway.
[0035] According to a third aspect of the present invention, a method of self-configuration of a network device, comprises the steps of:
[0036] obtaining, from a storage device, a previous network configuration for the device;
[0037] checking the previous network configuration to ascertain whether or not the configuration is still valid;
[0038] configuring device settings according to the network configuration if the validity check is positive; and
[0039] attempting to determine a new network configuration for the device and configuring device settings according to the new network configuration if the validity check is negative.
[0040] According to a fourth aspect of the present invention, a method of self-configuration of a network device connected between a first network device and a second network device, comprises the steps of:
[0041] attempting to determine a network configuration for the network device; and
[0042] configuring device settings of the network device such that the first network device appears, to the second network device, to be connected to the second network device, and the second network device appears, to the first network device, to be connected to the first network device.
[0043] According to a fifth aspect of the present invention, a method of self-configuration of a network device having at least two network connection ports, the method comprises the steps of:
[0044] passively snooping a network in which the network device is located and analysing data packets received on the ports;
[0045] determining information relating to a DNS server connected to the device according to information contained in data packets received on the ports; and
[0046] configuring device settings according to the DNS server information determined.
[0047] According to a sixth aspect of the present invention, a method of self-configuration of a network device having at least one network connection port comprises the steps of:
[0048] determining information relating to a gateway and a DNS server connected to the device according to information contained in data packets received on the port(s); and
[0049] configuring device settings according to the gateway and DNS server information determined to enable the device to connect to the Internet.
[0050] According to a seventh aspect of the present invention, a self-configuring network device has a storage device containing an executable code, wherein the device is adapted to execute the code to perform the method in accordance with any one or more of the first to sixth aspects of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0051] Examples of the present invention will now be described in more detail with reference to the accompanying drawings, in which:
[0052] FIG. 1 shows a schematic diagram of an exemplary embedded LAN device implementing the present invention;
[0053] FIG. 2 shows the connection terminals of the device of FIG. 1 ;
[0054] FIGS. 3 a and 3 b show an example of a network configuration before and after installation of the device of FIG. 1 , respectively;
[0055] FIG. 4 shows a flow diagram of a packet analysis routine performed by the device of FIG. 1 ;
[0056] FIG. 5 shows a flow diagram of a database structure stored in the device of FIG. 1 ;
[0057] FIGS. 6 a and 6 b show a flow diagram of a probing and interrogation routine performed by the device of FIG. 1 ;
[0058] FIG. 7 shows a flow diagram of a WAN port determination routine performed during the probing and interrogation routine;
[0059] FIG. 8 shows a flow diagram of a “Normal DHCP” device mode implementation;
[0060] FIG. 9 shows a schematic diagram of the device of FIG. 1 connected in a “Limited MAC DHCP” mode;
[0061] FIG. 10 shows detail of an ideal arrangement of a device connected in a “Limited MAC DHCP” mode;
[0062] FIG. 11 shows detail of an actual arrangement of the device of FIG. 1 connected in “Limited MAC DHCP” mode;
[0063] FIG. 12 shows a flow diagram of device operation in Limited MAC DHCP mode for a packet received on the LAN port;
[0064] FIG. 13 shows a flow diagram of device operation in Limited MAC DHCP mode for a packet to be sent from the LAN port;
[0065] FIG. 14 shows a flow diagram of device operation in Limited MAC DHCP mode for a packet to be sent from the WAN port;
[0066] FIG. 15 shows a flow diagram of device operation in Limited MAC DHCP mode for a packet received on the WAN port; and
[0067] FIG. 16 shows a flow diagram of routine interoperation for device configuration.
DETAILED DESCRIPTION
Exemplary Device
[0068] The exemplary device of FIG. 1 comprises a LAN port 1 , a WAN port 2 , a telephone port 3 and a telephone line port 4 . In the setup of FIGS. 2 and 3 b a first Ethernet cable 5 is connected between a PC 6 and the LAN port 1 , and a second Ethernet cable 7 is connected between a broadband modem/router 8 and the WAN port 2 . A first telephone cable 9 is connected between a telephone 10 and the telephone port 3 , and a second telephone cable 11 is connected between a telephone line 12 and the telephone line port 4 . The LAN and WAN ports 1 , 2 have RJ45 type connectors and the telephone and telephone line ports 3 , 4 have RJ11 type connectors.
[0069] The LAN and WAN ports 1 , 2 are connected via respective physical layers (PHYs) to a communications processor 13 . The communications processor 13 includes a Reduced Instruction Set Computer (RISC) processor, two Media Access Controllers (MACs), a Serial Peripheral Interface (SPI) and a Time Division Multiplexer (TDM). The communications processor 13 is connected to two storage devices 14 , 15 . The first storage device is a non-volatile “Flash” storage 14 , which is used to permanently hold software to be executed by the communications processor 13 and also to hold any configuration information relating to the device and its surroundings that is required by the software to be permanently stored. The Flash 14 interfaces with the communications processor 13 via a parallel interface. The second storage device is Synchronous Dynamic Random Access Memory (SDRAM) 15 . When the device is powered on, the communications processor 13 executes the software in the Flash 14 and copies the run time software into SDRAM 15 . SDRAM 15 is then used for program execution and volatile data storage at run time.
[0070] The telephone port 3 is connected via a Subscriber Line Interface Circuit (SLIC) 16 to a first line Coder-Decoder (CODEC) 17 . The line CODEC 17 provides an interface between the telephone 10 connected to the telephone port 3 and digital telephony. The telephone line port 4 is connected via a Data Access Arrangement (DAA) 18 to a second line CODEC 19 . The line CODEC 19 provides an interface between the telephone line 12 connected to the telephone line port 4 and digital telephony. The DAA 18 provides electrical isolation of the telephone line 12 from the device whilst enabling physical connection between these entities. The communications processor 13 configures and controls the line CODECs 17 , 19 via the SPI. The communications processor 13 also sends and receives voice samples using the TDM interface.
[0071] The communications processor 13 executes all software required to perform the operations of the device including drivers to control all of the external interfaces, including the ports 1 to 4 , drivers to control all internal peripherals, including the Flash 14 and SDRAM 15 , an Operating System (OS), IP communication, Voice-Over IP (VoIP) signalling software, and voice CODECs and algorithms.
[0072] In addition to the specific device components mentioned above, the device further includes a power supply connection, General Purpose Input Output (GPIO) pins including interrupts, LEDs, buttons and others as will be appreciated by those skilled in the art.
[0073] Upon installing the device, for example as shown in FIG. 3 b , and described above, and connecting a power cable to the power supply connection and switching on the device, the communications processor 13 executes software stored in the Flash 14 , as described previously. Next will be described details of device operation upon executing the parts of the software related to the present invention.
Packet Analysis
[0074] The first operation performed relates to the initialisation of an analysis routine for analysing packets of data received on the LAN and WAN ports 1 , 2 in order to initialise or update a database of information relating to the networks. The database is stored in the SDRAM 15 . The software code relating to packet analysis receives copies of all network packets received on LAN and WAN ports 1 , 2 . The code uses this information to initialise or update entries in the database.
[0075] The code uses the port information to determine what, if any, MAC addresses have been seen on each port 1 , 2 ; IP address(es) that are associated with each observed MAC address; and properties associated with the MAC addresses and IP addresses. The port information is entered into the database having the following entry fields: a list of the device ports; a list of MAC addresses per port; a list of IP addresses per MAC address; and a list of the properties associated with the ports, MAC addresses and IP addresses.
[0076] From time to time (described further in the following “Probing and Interrogation” section) the device issues “loopback” packets, which it sends out from each of the ports 1 , 2 . These loopback packets are identifier packets, which are unlike any other packets that will be received on the ports 1 , 2 . The purpose of the loopback packets is to enable the device to determine whether or not one of the ports 1 , 2 is connected to another of the ports 1 , 2 . If, for example, the device is installed such that an Ethernet cable has its one end connected to the LAN port 1 and its other end connected to the WAN port 2 then a loopback packet sent out from either port will be routed back and received on the other of the ports. The packet analysis routine is configured to handle such loopback packets as well as packets more typically received on the WAN and LAN.
[0077] A flow chart of the analysis process is shown in FIG. 4 . A packet received on one of the ports 1 , 2 is checked for its, so-called, Ether type. Four generic Ether types are discriminated. Type 1 is the loopback test packet described above. Type 2 is an Address Resolution Protocol (ARP) packet which allows a physical network address (such as a MAC address) to be determined if a logical network address (such as an IP address) is known. Type 3 is an IP packet and type 4 is all other packets.
[0078] The packet analysis routine runs continuously to ensure the network information database is up-to-date. FIG. 5 illustrates the database structure and together with FIG. 4 illustrates how the database entries are initialised or updated.
[0079] As shown in FIG. 4 , an incoming packet on a particular port is first checked for its Ether type. If the Ether type is type 1 , a loopback test packet, then the port properties list in the database is updated to reflect the loopback status for the port the packet was received upon. The device may use the loopback status entries in the database to disable a particular port, as will be described in the following section. No entries in the MAC or IP address lists will appear against the port having a positive loopback status and the routine immediately moves to detect any incoming packets on the next port, as shown in FIG. 5 .
[0080] If the Ether type is type 2 , an ARP packet, or type 3 , an IP packet, then the information in the packet is used to update MAC and IP entries in the database. First, as shown in FIG. 5 , the database MAC list for the port the packet was received upon is updated with the MAC address of the received packet. If this is the first MAC entry in the database for that port then this address in entered as MAC Entry 1 in the MAC list. The routine checks whether the MAC address was seen as a source or a destination MAC address and stores this information in the MAC properties list against MAC Entry 1 in the database. Furthermore, the routine checks whether the packet contains a DHCP response for this MAC address and sets a DHCP response flag accordingly in the MAC properties list. If a different MAC address has previously been stored as MAC Entry 1 then the above MAC address and associated MAC properties are stored in the next available MAC Entry location in the database. For the received MAC address the routine also checks for an associated IP address seen in the packet, as well as whether this was seen as a source or destination IP address. This information is stored in the IP address and IP address properties lists in the database under IP Entry 1 . If a different IP address has previously been stored as IP Entry 1 then the above IP address and associated IP properties are stored in the next available IP Entry location in the database.
[0081] If the Ether type is type 3 , the routine further checks whether or not the IP packet is a User Datagram Protocol (UDP) packet. This further check is shown schematically in the flow diagram of FIG. 4 . If it is not a UDP packet then no further information to that described above is stored in the database for that packet. If the packet is a UDP packet then a check is made as to whether the packet was a DHCP server (DHCPS), a DHCP client (DHCPC), or a DNS packet. The IP properties list in the database stores details of whether a MAC response has been seen for the particular MAC address, whether a DHCP request or response has gone to or from the particular IP address, or whether a DNS server request or response has gone to or from the IP address, and sets flags accordingly.
[0082] All other packets are considered as type 4 and are ignored by the routine for the purposes of initialising or updating the database.
[0083] The database information is used by a probing and interrogation software code held in the Flash 14 and executed by the communications processor 13 . Operations performed by execution of the probing and interrogation code are described below. The size of the database is limited to prevent memory usage problems on the device.
Probing and Interrogation
[0084] The probing and interrogation code carries out a series of tests, which result in packets being transmitted, and subsequently the database interrogated in order to determine the network setup. The probing and interrogation routine can be stopped, paused/restarted and started afresh under the control of an external agent. For example, starting afresh would happen if any significant change occurred to the network, for example disconnection of the broadband/modem router 8 , no further response from a DHCP server, or no response from a gateway for a prolonged period of time.
[0085] An object of the probing and interrogation routine to determine which of the ports 1 , 2 has been connected to the LAN and WAN, irrespective of any port designation on the device itself. For example, if the “LAN” port 1 as designated on the device is actually connected via Ethernet cable 7 to the broadband modem/router 8 , and the “WAN” port 2 as designated on the device is actually connected via Ethernet cable 5 to PC 6 , then the routine is operable to effectively redefine the ports such that during device configuration port 1 becomes the WAN port and port 2 becomes the LAN port. This is a particular, though not exclusive, problem where, as in the exemplary device embodiment of the implementation of the present invention, the same type of cable connectors may be fitted to ports 1 and 2 of the device.
[0086] The routine also has the object of determining whether or not DHCP is being used on the network, and if so which of the ports 1 , 2 the DHCP server is operating on. If DHCP is being used, the routine also detects whether or not the network places a limitation on the number of MAC addresses that can be supported on it with a view to device configuration, described in the following section.
[0087] Tests performed by the probing and interrogation routine will now be described with reference to FIGS. 6 a and 6 b.
[0088] As mentioned in the previous section, the device issues loopback test packets to see if the ports 1 , 2 are connected in any way. The probing and interrogation routine instigates the issuance of these packets, waits for a short period of time, and then interrogates the database to see if any port has seen this packet. If the packet is received on one of the ports 1 , 2 then it is disabled.
[0089] Assuming that a loopback packet has not been seen then the routine continues and sends a DHCP request to detect for a DHCP server on the network. After issuing the DHCP request, the routine waits for a predetermined period of time and then looks in the database for a response from a DHCP server to the request. Details of how the DHCP response is stored in the database appear in the previous section.
[0090] If a DHCP server is detected then two potential DHCP device configurations may be possible. A further test is therefore performed to ascertain which of these is suitable before proceeding to execute the device configuration routine. The device may be configurable in either a “Normal DHCP” mode or in a “Limited MAC DHCP” mode. In the first scenario, there is no limit on the number of MAC addresses available on the network. In the second scenario, there is a network limit on the number of MAC addresses but the MAC address of the device itself happens to be the first MAC address observed (for example if the PC 6 attached to the device is not powered on).
[0091] The further test consists of sending a DHCP request using a second device MAC address. If a response to the second DHCP request is seen then the device assumes there is no limit on the number of MAC addresses available, at least in so far as it is possible for the MAC address of the device itself to exist on the network. In this case, the routine elects “Normal DHCP” mode, which result is detected and used in the device configuration routine described in the following section.
[0092] If no response to the second DHCP request is seen then the routine performs further checks to see if the MAC address of an attached PC 6 can be detected. Irrespective of the outcome of these further checks, the routine elects “Limited MAC DHCP” mode, which result is detected and used in the device configuration routine described in the following section.
[0093] If no DHCP server is detected in response to the original DHCP server request, then there are two potential reasons for this. Either there is no DHCP server, or there is a DHCP server but there is a limit on the number of MAC addresses on the network and the MAC address of the attached PC 6 , for example, has already been noted by the broadband modem/router 8 , for example, hence it does not respond to the DHCP server request.
[0094] In order to determine whether or not there exists a DHCP server, the routine performs a further check to see if it can determine the MAC address of the attached PC 6 . If this further check is successful then the routine tests whether a DHCP server responds to the MAC address of the attached PC in a similar way to that described above. If a DHCP response to the PC MAC address is seen then the routine elects “Limited MAC DHCP” mode, which result is detected and used in the device configuration routine described in the following section.
[0095] If no PC MAC address can be found, or if no DHCP response is seen in response to the PC MAC address if found, then the routine determines whether the information obtained thus far is sufficient for either an alternative self-configuration mode using information from the database, or a manual configuration if there is insufficient information in the database, or whether the probing and interrogation routine is to restart. The self-configuration and manual configuration modes will be described in the following section. If a significant change, as described previously, is detected on the network then the probing and interrogation routine will be restarted.
[0096] The final step of the probing and interrogation routine is to determine which of the ports 1 , 2 is the WAN port. As mentioned previously, the exemplary device has one LAN port 1 and one WAN port 2 . However, the skilled person will appreciate that a plurality of LAN ports 1 may be provided. In either case a single WAN port 2 is provided and so it is necessary to determine which of the ports 1 , 2 has actually been connected to the WAN, irrespective of the port designation on the device.
[0097] FIG. 7 shows a flow diagram of the WAN port determination. The WAN port is determined by sending an Internet Control Message Protocol (ICMP) request with a predetermined time-to-live, for example, one, to the determined broadband modem/router 8 MAC address. The device then receives and identifies an ARP request from the gateway, responds to the ARP request to enable the gateway to send a response to the network device identifying that the time-to-live of the ping request has expired. Upon receipt of the time-to-live expired response from the gateway, the device can determine the gateway IP address from this received time-to-live expired response. Based on which of the device ports 1 , 2 this time-to-live expired response is received, the WAN port can also be determined.
[0098] The probing and interrogation routine is monitored by a probing control code, which monitors a physical connectivity status of the device interfaces, i.e. the LAN and WAN ports 1 , 2 . This monitoring is performed continuously to monitor when new devices are physically connected to, or disconnected from, the device interfaces. Any significant changes to the physical connectivity status of the device interfaces causes the probing control code to order a restart of the probing and interrogation routine to redefine the port status and the device configuration mode.
[0099] In case of transient problems detected during running of the probing and interrogation routine, the probing control code may pause the routine. If after successful device configuration, as will be described in the following section, the IP networking connectivity subsequently fails, the probing control code may also act to reset the probing and interrogation routine to its default state (i.e. an empty database) and restart the routine.
[0100] The probing and interrogation routine therefore attempts to determine the port status, the WAN port, and the device configuration mode.
Device Configuration
[0101] Similar to the software routines described above, a device configuration routine is stored in the Flash 14 . Once the probing and interrogation routine has completed for the first time, the device configuration routine is executed. The device configuration routine has as its object to configure the device's IP and physical interface settings.
[0102] If the packet analysis and probing and interrogation routines have been able to determine sufficient information, the device configuration routine configures the device IP settings to enable the device to connect to the Internet. The device configuration routine consists of configuring the device physical interfaces and IP settings, storing the current configuration settings in the database, and informing the probing and interrogation routine to determine the WAN interface. Once the WAN interface has been determined the device configuration routine continues and configures the physical interfaces, and configures Quality of Service settings on the WAN interface before finally storing the current configuration in the database.
[0103] If the probing and interrogation routine has not been able to determine sufficient information, an error message is generated and manual, conventional, user input is required to configure the device in a static configuration.
[0104] In the following, it is assumed that the routines have been able to determine sufficient information for one of the above described self-configuration modes to be implemented to configure the device. These configuration modes will now be described in detail.
Normal DHCP Mode
[0105] In unrestricted, normal DHCP mode, all device ports 1 , 2 are connected to a Layer 2 Bridge. The bridge is connected to a single IP interface on which there is a DHCP client to determine network configuration settings. This is summarised by FIG. 8 . Since there is no restriction on the number of MAC addresses available through the broadband modem/router 8 , the device configuration is straightforward and all information required may be readily obtained during running of the setup routines described above. The device may therefore be simply plugged in and the PC user experience will remain unchanged after device installation as before.
Limited MAC DHCP Mode
[0106] The object of this mode is to configure the device such that one half of the device acts as the PC 6 to the broadband modem/router 8 and the other half of the device acts as the broadband modem/router 8 to the PC 6 . The effect of this is that each half of the device mirrors the MAC and IP addresses of the device (i.e. PC 6 or broadband modem/router 8 ) that is connected to the other half.
[0107] A schematic of the implemented device arrangement is shown in FIG. 9 . The broadband modem/router 8 operating in Limited MAC DHCP mode is connected to the Internet and to one side of the device. The PC 6 is connected to the other side of the device. The device is configured such that the broadband modem/router 8 “sees” the PC 6 , and the PC 6 “sees” the broadband modem/router 8 as if the device wasn't there. By this setup, despite the limited number of MAC addresses available through the broadband modem/router 8 , the PC user experience remains unchanged after device installation as before.
[0108] A simple ideal implementation of this configuration mode is shown in detail in FIG. 10 . The mirroring effect achieved by this configuration mode is evident from the assignment of MAC and IP addresses to the PC, device and network access device. The device is configured with two IP stacks, with interfaces attached to the LAN and WAN ports. The WAN side IP stack is connected to a DHCP Client (to obtain network configuration) and also to a forwarder. The LAN side IP stack is connected to a DHCP Server, which is able to provide the PC or router on the LAN with the same network configuration that the WAN port received via its DHCP client. In the diagram DHCP Lease is a term used to describe the network configuration received from a server or passed to a client. The LAN side IP stack is also connected to the forwarder and management.
[0109] The PC “sees” the LAN side of the device as if it is the network access device since it appears having the IP address of the gateway and the MAC address of the modem. The network access device “sees” the WAN side of the device as if it is the PC since it appears having the shared IP address of the PC and the MAC address of the PC.
[0110] The forwarder merely passes packets from WAN interface to LAN interface and vice-versa. However, if the network access device sees the MAC address of the device first (i.e. Limited MAC DHCP mode is entered because no second DHCP response was received during the probing and interrogation routine) then it is also necessary to translate MAC addresses between the device MAC address and the PC MAC address when packets pass between the LAN and WAN via the forwarder. Whilst this ideal implementation is valid for a number of device applications, the exemplary device in accordance with the embodiment of the present invention requires a higher level of complexity due to some software constraints. Accordingly, the following description refers to an actual implementation of this configuration mode with reference to the ideal model described above.
[0111] Implementation of the Limited MAC DCHP configuration mode on the exemplary device in accordance with the embodiment of the present invention will now be described with reference to FIG. 11 . The requirement for this is that the device has a single IP stack to which both ports are connected. As can be seen from comparing FIGS. 10 and 11 , in the arrangement of FIG. 11 the LAN IP interface effectively sits between a NAT engine and the physical LAN port 1 . This allows the logical IP interface to use a different, pseudo IP address, rather than that used by the network access device on the WAN side. At the “MAC” level the forwarder is used to directly transfer information between the WAN and LAN interfaces. The single IP stack can communicate with both interfaces in a coherent manner and allows management of the device and DHCP configuration of the attached PC. The NAT engine translates between this pseudo IP address used by the LAN port 1 and the shared IP address that is required by the PC 6 to connect through to the network device 8 . The NAT translates addresses in the IP headers and also the contents of any DHCP packets. The pseudo IP address can also be used to manage the device from the LAN without conflicting with management of the network access device 8 on the WAN side. The NAT engine does not affect packets destined from the broadband access device to the PC and vice-versa. Processing by this arrangement will now be described.
[0112] In order to process packets received on the WAN and LAN ports 1 , 2 appropriately the following information is required and maintained by the configuration mode, and stored in the database: MAC addresses of the device WAN and LAN ports 1 , 2 , broadband gateway/router 8 , PC 6 (this may not be known at start of configuration process, for which see below); information on whether the broadband gateway/router 8 has stored the MAC addresses of the device or PC 6 ; and IP addresses of the broadband gateway/router 8 , and shared and pseudo IP addresses.
[0113] As discussed previously, it is possible that in executing the probing and interrogation routine, Limited MAC DHCP mode was correctly selected but the PC 6 connected to the LAN port 1 of the device is not powered on or connected. In this scenario the routine checking received packets on the LAN port 1 adopts the first MAC address seen on the LAN port 1 as the PC 6 MAC address (this has been omitted from diagrams and following description for clarity of the general case).
[0114] Operation of Limited MAC DHCP mode will now be described with reference to FIGS. 12 to 15 relating to 4 operational cases, namely: packet received on the LAN port 1 ; packet to be sent from the LAN port 1 as a result of transmission from the local IP stack; packet to be sent from the WAN port 2 as a result of transmission from the local IP stack; and packet received on WAN port 2 .
[0115] Packets send to the forwarder by the LAN port are immediately sent via the WAN port and vice-versa.
[0116] Turning first to FIG. 12 there is shown a flow diagram of processing performed for a packet received on LAN port 1 . Firstly, as in previous routines, it is judged what is the Ether type of the received packet, i.e. ARP or IP.
[0117] If the packet is an ARP packet and is an ARP request for the IP address of the broadband modem/router 8 , then an appropriate ARP response is to be sent with information to reply to the request.
[0118] If the packet is an ARP packet and is an ARP request for another device, then this request is sent to the forwarder. If the device MAC address is being used on the WAN interface, then the MAC address of the PC 6 from which the ARP packet was received is replaced with the device MAC address before sending to the forwarder.
[0119] If the packet is an ARP packet but is not an ARP request packet, then the packet is sent to the local IP stack.
[0120] If the packet is an IP packet and is destined for the pseudo IP address (and hence the local IP stack) and is from a, so-called, unicast IP source address, then NAT is applied to the packet headers to change the source (SRC) IP address to the pseudo gateway IP address. If the packet is a UDP DHCP client packet then NAT is applied to the packet to change the PC 6 IP address to the pseudo gateway IP address in the DHCP and IP packets. After application of any applicable NAT rules the packet is sent to the local IP stack.
[0121] If the packet is an IP packet but is not destined for the pseudo IP address (and hence not for the local IP stack) and it is not a packet from a DHCP client, then the packet is sent to the forwarder. If the device MAC address is being used on the WAN interface, then the MAC address of the PC 6 from which the IP packet was received is replaced with the device MAC address before sending to the forwarder.
[0122] Turning next to FIG. 13 there is shown a flow diagram of processing performed for a packet to be sent from LAN port 1 as a result of transmission by the local IP stack. Again, it is judged what is the Ether type of the packet to be sent, i.e. ARP or IP.
[0123] If the packet is an ARP packet and is an ARP request, then an ARP response is sent back to the LAN IP stack. If the packet is any other ARP packet, then this is transmitted out of the LAN port 1 .
[0124] If the packet is an IP packet, but does not have a broadcast destination address, then NAT is applied to the headers to change the SRC IP address to the PC 6 IP address. If the packet is from a DHCP server, then NAT is applied to the packet to change the pseudo gateway IP address to the PC 6 IP address. After application of any applicable NAT rules the packet is transmitted out of the LAN port 1 .
[0125] Turning next to FIG. 14 there is shown a flow diagram of processing performed for a packet to be sent from WAN port 2 as a result of transmission by the local IP stack. Again, it is judged what is the Ether type of the packet to be sent, i.e. ARP or IP.
[0126] All packets that are transmitted from the device are ‘cached’ by storing information about each session prior to transmission. Multiple IP sessions are recorded enabling multiple services from the device. Sessions are limited (in terms of total number) and also time-out after a set period of time. This limits any potential interactions with LAN side traffic. The information stored per session relates to the destination IP address (compared with source IP address on receive), the IP protocol, the source port (compared with destination port on receive), and the destination port (compared with source port on receive).
[0127] Finally, turning to FIG. 15 there is shown a flow diagram of processing performed for a packet received on WAN port 2 . On reception the packet is first matched against a cached session. If a match is found the packet is passed to the WAN IP stack. If the packet did not match and the packet was not an IP packet it is also passed to the WAN IP stack. All other packets are passed to the forwarder. Prior to doing so, if the MAC address of the device is being used on the WAN interface, then this MAC address is replaced with that of the PC 6 .
[0128] Packets sent to the forwarder by the LAN port are immediately sent via the WAN port and vice-versa.
Static Snooped Mode
[0129] The object of this mode is to statically configure the IP addresses based partially on information stored in the database and by trialling potential IP addresses for the device to complete the configuration.
[0130] From the packet analysis routine, a number of network settings of the broadband modem/router 8 (gateway), DNS server and local subnet and IP address will be stored in the database.
[0131] In order for the database to hold all the required information it is necessary to have seen/snooped packets containing particular information. This is enabled by the fact that the device has both WAN and LAN ports 1 , 2 and sees all packets forwarded between them by the forwarder.
[0132] The broadband modem/router 8 can be identified by looking through the database of network information for a MAC address having multiple destination IP addresses associated with it. The MAC address will be that of the broadband modem/router 8 . Once the broadband modem/router 8 has been identified, the local subnet can be determined.
[0133] Once the MAC address of the broadband modem/router 8 has been identified, its local IP address (which may not have been already snooped) can be determined. This is done by sending the broadband modem/router 8 a packet with a time-to-live (TTL) of 1, containing a destination IP addresses that is further upstream in the network. The broadband modem/router 8 will respond with an ICMP reply containing its IP address on the local subnet.
[0134] Once the local subnet is known, it is possible to ‘try’ potential IP addresses for the device using ARPs to see if the IP address is already used on the subnet. The device ARPs to find free IP addresses on the local subnet. It assumes a Class C subnet of the form A.B.C.X, and tries all valid values of X until no clash is found. If the entire subnet is allocated, then the device stops the configuration process. If a free address is found the device can be configured.
[0135] The DNS server can easily be identified by searching for DNS packets from clients wanting to resolve an address. The server address will be the destination IP address in the packet.
State Saving and Restoration
[0136] Once the device is configured, the configuration is stored in a database in Flash. On restart the device will read the saved configuration from Flash and configure the device accordingly. If this configuration is still satisfactory, then nothing more is done. If it is not then the probing control routine will start the probing and interrogation routine, which may subsequently lead to a new configuration.
Static IP Address Configuration—Safe Mode
[0137] If it is not possible to automatically configure the device, it is still desirable to be able to contact it over the network. The device therefore has provision for by-passing all of the above configuration routines, and instead configures the device with a fixed fail-safe IP address. Such an address could be a private IP address such as 192.168.1.1 or 10.0.0.1. This safe mode could be entered if, for example, the user held down a button on the device as it is turned on.
[0138] An overview of the device configuration routines is shown in the flow diagram of FIG. 16 . This diagram illustrates how the device interfaces and packets received or transmitted thereon are used to configure the device.
[0139] In addition to the purely exemplary embodiment of the present invention as described above, it will be appreciated by those skilled in the art that various modifications and alternatives are envisaged within the scope of the invention which is defined by the appended claims.
[0140] For example, the packet analysis and probing could be combined, eliminating the need for a database of results. Instead, the device configuration could be implemented or updated directly according to the device status. This option, though, would be less flexible than the embodiment described above.
[0141] Each possible configuration mode could be tested in parallel, to speed up configuration determination. This would only require a minor increase in processing power but the programmatic complexity would increase significantly and so this option was not chosen for the embodiment of the invention described above.
[0142] Rather than the half-NAT option chosen for the Limited MAC mode described above, full NAT could be employed. However, NAT would affect the end user experience as all inbound applications would stop working and some outbound applications may be affected.
[0143] As an alternative to using DHCP client and server in the Limited MAC mode, it would be possible to ‘snoop’ the DHCP information travelling between the broadband modem/router 8 and the PC 6 and use this as the addressing information for the device. This was rejected for the specific embodiment described above since this fails in the case where the broadband modem/router 8 learns the MAC address of the device.
[0144] Point to Point Protocol over Ethernet (PPPoE) is a protocol used by some cable operators to provide connectivity between a PC or home/business router and a network access device. In the case where the device of the exemplary embodiment described above is connected between the PC or router and the network access device, PPPoE may be detected in the same way that DHCP is detected in the above embodiment, by sending out a packet and analysing the result. Detection of this configuration scenario has not been implemented in the exemplary device but it is envisaged that this will be an add-on feature for future devices. In this situation there would be an additional mode PPPoE configuration mode.
[0145] In the particular embodiment described above, the ports 1 and 2 are Ethernet ports. However, the present invention has applicability to many other port types such as BlueTooth(®); ZigBee(®); Ethernet-like ports; 802.11; Powerline(®); HomePlug(®); and UWB.
[0146] Whilst the present invention has been described with reference to the exemplary device above it will be appreciated by those skilled in the art that the aspects of the invention may be applied to any embedded/edge device connected between a network access device and a router or PC, for example. | A method of self-configuration of a network device having at least one network connection port, comprising the steps of, after booting of the network device, actively probing a network in which the network device is located and analysing data packets received on the port(s), attempting to determine a network configuration for all network connections the device can make according to information extracted from the received data packets, and configuring device settings according to the network configuration determined. | 7 |
RELATED APPLICATIONS
This is a continuation-in-part application of my prior patent application, Ser. No. 943,068, filed Dec. 18, 1986 and entitled TIRE INFLATING AND DEFLATING SYSTEM AND APPARATUS which has now issued as U.S. Pat. No. 4,782,878.
INCORPORATION BY REFERENCE
Incorporated by reference herein and filed as a part hereof is my prior patent application, Ser. No. 943,068, filed Dec. 18, 1986 (hereinafter referred to as "parent patent") and U.S. Pat. No. 2,989,999 to E. L. Holbrook et al dated June 27, 1961.
This invention relates generally to a vehicle tire pressure control system and more particularly to a quick dump valve for use in and in combination with such system.
While the invention is particularly adaptable for use in a vehicle tire pressure control system of the type disclosed in the parent patent, the quick dump valve and system disclosed herein can be utilized in other types of vehicular tire pressure control systems, and may have application in other non-vehicular, fluid controlled systems such as may be encountered in the industrial sector.
BACKGROUND OF THE INVENTION
It is well known in the art to provide vehicles with on board systems for achieving inflating and/or deflating of vehicle tires and/or the checking of the pressure of air in the vehicle tires. The ability to selectively increase or decrease tire pressure is desirable in connection with optimizing operation of the vehicle under variable and changing conditions including, for example, weather, vehicle load, terrain and vehicle speed. Another advantage of such systems is their ability to isolate air under pressure in each vehicle tire from the remainder of the system so that any problem, such as a leak, encountered in connection with one tire does not affect the air pressure in the other vehicle tires. Generally, most of the tire pressure control systems use a tire isolating valve interposed between the tire and the tire pressure control system and the sealing arrangement effected by the isolating valve is not severely strained because the isolating valve is not subjected to system air pressure other than when the system is operated to achieve inflation, deflation or pressure checking.
In my parent patent, an electronic-pneumatic control system is disclosed in combination with a unique tire isolating valve of the poppet type which, when manually actuated, provides a fully automated, highly accurate system for controlling the inflating, deflating and pressure checking of the vehicle's tires. One of the features of my parent patent is to conceptually utilize system pressure to initialize whatever tire pressure function the system is being instructed to do and, once initialized, utilize an orificing arrangement to sense the tire pressure which in turn controls the system pressure and valving to achieve whatever tire pressure function the system is being asked to perform. For example, when the system in my parent patent is manually placed in a discharge or tire deflation mode, system pressure is initially used to open the isolating valve. The tire pressure is then essentially discharged to atmosphere through an orifice until a predetermined lower tire pressure is accurately sensed. At that point in time, the valving system is again actuated to instantaneously close the tire isolating valve by rapidly dumping the manifold pressure to atmosphere thus bypassing the orifice sensing arrangement.
In practice, the valving and the system disclosed in my parent patent rapidly deflates the system in the tire deflation mode and satisfies most vehicular applications requiring tire deflation. However, there are applications, for example in military transport vehicles, where it is desired to have almost instantaneous deflation. This can occur when the vehicle encounters mud, water or sand and must keep its speed as high as possible. In such instances, tire deflation systems which exhaust the tire air through the system manifold or the system manifold lines will inherently produce a delay in the tire deflation mode. One can appreciate the significance of the problem by visualizing a six-wheel vehicle deflating all of the air from its six tires through one manifold line. Further compounding the problem is a definite trend over the past several years to increase tire size on such vehicle. Obviously this requires that a larger fluid mass be discharged to achieve the same deflation pressure of older vehicles using smaller tires.
Quick dump valves are well known in the general art and the use of a quick dump valve to achieve rapid deflation of a tire in a vehicular tire pressure control system has been recognized in the prior art. A typical approach is disclosed in U.S. Pat. No. 2,989,999 to Holbrook, incorporated by reference herein. In Holbrook, a quick dump valve is used at each tire to directly discharge the fluid in the tire to atmosphere upon command by air (which is at a higher pressure than the system pressure) being ported to the dump valve. The quick dump valve is spring biased and whenever the tire pressure drops below the compressed force of the spring, the valve shuts off to stop further tire deflation. This is workable so long as only one lower, tire deflation value is required and so long as the spring rate can be accurately correlated to the pressure sensed in that particular tire to which the valve is attached. Today, several deflation pressures are typically required with little pressure variance permitted between the vehicle's tires.
SUMMARY OF THE INVENTION
Accordingly, it is a principal object of the invention to provide a tire pressure system and/or a quick discharge valve which quickly deflates the tires on a vehicle to a predetermined pressure which in turn is directly and accurately controlled by the pressure of the fluid in the tires.
This object along with other features of the invention is achieved in a system for controlling the inflation pressure of a pneumatic tire and the like which includes a source of fluid at a first system pressure and at a second higher biasing pressure. A manifold is in fluid communication with the source of fluid and an isolating valve is adapted to be in fluid communication with the tire and with the manifold. An electronic-pneumatic valving arrangement associated with the manifold controls the flow of fluid through the manifold to the isolating valve and is also capable of porting any fluid within the manifold to atmosphere whereby the pressure within the tire may be increased, decreased or maintained at predetermined levels. A quick dump valve arrangement is adapted to be in fluid communication with the fluid source through the manifold, with the fluid in the tire and with the atmosphere. The quick dump valve is actuable to a dump position by only source fluid at the high biasing pressure to provide fluid communication directly from the tire to the atmosphere whereby the tire can be quickly deflated upon command. Specifically, the electronic-pneumatic valving arrangement is effective to cause the isolating valve to also discharge fluid from the tire to the atmosphere through the manifold while the quick dump valve is simultaneously discharging fluid directly to the atmosphere. The tires are thus being deflated in the deflation mode at a very high rate by the exhaust from both valves.
In accordance with another feature of the invention, the exhausting of a portion of the fluid in the tire through the isolating valve occurs through a deflation valve in the manifold having an orifice arrangement associated therewith and a transducer in combination with the orifice. When the transducer senses a predetermined pressure in the tire, the fluid in the manifold leaving the tire is ported from the discharge valve to a quick exhaust valve which rapidly depressurizes the fluid in the manifold causing the quick dump valve and also the isolating valve to immediately cycle to its off position. In this manner, the fluid pressure sensed in the tire is used to control the stopping of the fluid exhaust from the tire at an accurate preset level. Systemically, any number of predetermined deflation values can be established within the system. That is, not only can the lowest pressure level at which the valves cycle off be varied, but any number of lower pressure levels can be preset. That is, the system operator control knob could be preset to any number of predetermined pressures, although only three are shown in the preferred embodiment, and when actuated, the system will rapidly exhaust to that level.
In accordance with another specific feature of the invention, a separate high pressure reservoir containing a discrete volume of fluid at the biasing pressure is provided. An electronic pulse valve arrangement within the manifold which is in fluid communication with the high pressure reservoir is provided. When the system requires a tire deflation, the pulse valves are actuated into an "on" position for a brief period of time to provide fluid communication from the high pressure reservoir to the quick dump and isolating valve arrangements through the existing system manifold lines. As indicated above, in this brief period of time, the quick dump valve arrangement is actuated to port the fluid in the tire to atmosphere and to open the isolating valve so as to provide fluid communication between the fluid in the tire and the manifold while simultaneously opening the manifold to atmosphere through the metered deflating valve. The timed opening of the pulsed valve arrangement is approximately 600 milliseconds which is sufficient to actuate the quick dump and isolating valve arrangements before the pulse is almost instantaneously dissipated by the opening of the deflating valve. Accordingly, retrofit applications are easily accomplished by simply adding the pulse valves, the quick discharge valve and the reservoir to the existing system manifold. In accordance with another aspect of the invention, that feature of the parent patent which provided a system which did not adversely affect the vehicle's air system brake pressure requirements is maintained in this invention by the use of a separate reservoir as the source of the fluid at biasing pressure, which reservoir is charged by the compressor normally supplied with the vehicle.
In accordance with another feature of the invention, the dump valve comprises a cylinder with a biasing inlet at one end in fluid communication with the source fluid and a tire inlet at the opposite end in fluid communication with the fluid in the vehicle's tire and an atmosphere outlet therebetween in fluid communication with the atmosphere. A sealed piston or spool is provided within the cylinder and positioned between the biasing inlet and the tire inlet and the piston is movable within the cylinder from a first position blocking fluid communication from the tire inlet to the atmosphere outlet and a second actuated position providing for fluid communication between the tire inlet and the atmosphere outlet. A spring biasing mechanism, in combination with the tire pressure acting on one end face of the piston, maintains the piston in its first or closed position even though fluid at system pressure may be present at the biasing inlet and acting on the opposite end face of the piston against the spring and tire pressure. When the fluid at the biasing inlet is at the higher biasing pressure, the spring biasing mechanism and tire pressure is overcome and the piston moves to its second, or open position to discharge fluid from the tire to the atmosphere. The dump valve is then maintained in its open position by a detent mechanism which exerts a mechanical force resisting movement of the piston to the closed position such that the detent mechanical force in combination with the pressure of the fluid at the biasing inlet is sufficient to overcome the biasing spring force tending to move the piston to its closed position. When the fluid pressure in the biasing inlet drops below a predetermined value (established by the transducer which actuates the quick dump valve to drop the pressure at the biasing inlet to zero) the biasing spring mechanism returns the piston to its first position to prevent further discharge of fluid from the tire to atmosphere. The detent mechanism is inoperative when the dump valve is in its closed position and the tire pressure force acting on the end face of the piston is inoperative when the dump valve is in its open position. Accordingly, a simple mechanical arrangement is utilized in a very simple valve structure which is controlled by the electronic-pneumatic mechanism of the system to accurately and quickly open and close the discharge of fluid in the tire to atmosphere. Importantly, the motion or balance of the valve is controlled by the fluid pressure at the valve's inlet.
In accordance with a more specific feature of the invention, within the housing of the quick dump valve, a second cylinder is formed having a second biasing inlet in fluid communication with the biasing inlet of the first cylinder and the second tire inlet in fluid communication with the tire inlet in the first cylinder. A poppet valve structure within the second cylinder permits fluid communication between the second biasing inlet and the second tire inlet when source fluid at system pressure or above is provided to the first biasing inlet. The poppet valve closes and prevents fluid communication when the pressure at the first biasing inlet drops below a predetermined value which is the same value established for return of the piston from the second to the first position in the quick dump valve. In this manner, both isolating and quick dump valves can be incorporated into a unitary structure using a common biasing inlet and a common tire inlet to insure instantaneous response of both valves to fluid at various predetermined pressure levels.
It is thus an object of the invention to provide a control system and valve which permits rapid discharge of the air from the vehicle's tire.
It is another object of the invention to provide a control system and valve which provides for rapid discharge of air from the vehicle's tires until a predetermined pressure level within the tire has been sensed.
It is another object of the invention to provide a quick dump valve arrangement for use in a vehicular tire pressure control system where manifold line size can be kept to a minimum.
It is yet another object of the subject invention to provide a tire pressure control system with a quick dump valve which, while requiring fluid at a high pressure to actuate, nevertheless is able to control the remaining parameters of the system at a lower system pressure, thus permitting all the valves and fluid flow components in the control system to be sized or designed only to withstand the lower system pressures.
It is another object of the invention to provide a tire pressure system where the exhausting of the tire fluid to atmosphere occurs at the individual wheels of the vehicle.
It is yet another object of the invention to provide a tire pressure control system where the tire can be rapidly exhausted to a plurality of several different, preset pressures.
Still a further object of the invention is the provision of a quick dump valve structure which is structurally compact, economical to produce, and efficient and accurate in operation.
Yet another object of the invention is to provide a quick dump valve which is actuated from off to on and on to off by fluid pressure.
DESCRIPTION OF THE DRAWINGS
These and other features and objects of the subject invention will become readily apparent to one skilled in the art upon a reading of the detailed specifications taken in conjunction with the following drawings which illustrate a preferred embodiment of the invention and which forms a part hereof and wherein:
FIG. 1 is a schematic representation of the component parts of a tire pressure system in accordance with the present invention and corresponds to FIG. 1 of the parent patent;
FIG. 2 and 2a are together a schematic representation of the component parts of the electronic and pneumatic control modules of the apparatus and correspond to FIGS. 2 and 2a of my prior patent;
FIG. 3 is schematic illustration of the pneumatic control module and a vehicle tire showing the position of the component parts thereof at the beginning of a tire deflating operation and corresponds generally to FIGS. 3 through 6 of my prior patent;
FIG. 4 is a plan view of a preferred tire quick dump valve in accordance with the present invention and corresponds to FIG. 7 of my prior patent;
FIG. 5 is a sectional elevation view of the quick dump valve taken along line 5--5 in FIG. 4 and corresponds to FIG. 8 of my prior patent; and
FIG. 5a is a detailed view of the detent mechanism shown in FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As noted in the "Description of Drawings", the drawings in this patent correspond to the drawings in my prior patent and, except where indicated below, the reference numerals shown in the drawings correspond to the reference numerals shown in the drawings of my prior patent. Accordingly, and except as otherwise indicated, the terminology of the components, the description of the components and the operation of the components as set forth in my prior patent applies to the system and components of this invention. The description of the preferred embodiment in this patent, will describe only the different components and functions of the tire pressure system and valves of this invention. The reader is referred to my prior patent for a detailed and complete explanation of the components and functioning of the tire pressure system shown in the attached drawings.
Referring now in greater detail to the drawings wherein the showings are for the purpose of illustrating the preferred embodiment of the invention only and not for the purpose of limiting the same, FIGS. 1 and 2 illustrate schematically the overall tire pressure system of the present invention. As noted, FIG. 1 is identical to FIG. 1 of my prior patent except that a high biasing pressure reservoir 39 is added to the air supply 16. This is accomplished by a charging conduit 300 in fluid communication with air supply conduit 15 at one end and in fluid communication with biasing pressure reservoir 39 at its other end through a one-way check valve 37. As described in my prior patent, it is contemplated that air supply 16 is generated from the compressor on the motor vehicle which supplies vehicular air pressure principally for operation of the vehicle's brakes. Normally, regulators are used in air supply 16 to maintain a vehicular system pressure of about 70-80 psi. The compressor, however, can and does develop a pressure of about 120-140 psi prior to entering the regulators and it is this pressure which is used to charge reservoir 39 through charging conduit 300. Thus, appropriate regulators, not show, within air supply 16, function to fully charge biasing pressure reservoir 39 to approximately 120 psi in a known manner. Fluid in high pressure reservoir 39 is then discharged through a discharging conduit 301 when a first pulse valve 41a is actuated. Discharge conduit 301 in turn is in fluid communication with air supply line 15 which in turn is in fluid communication with the manifold 14. Manifold 14 is identical to that disclosed in my parent patent with the exception of the addition of a second pulse valve 41b. Thus, FIG. 1 of the present invention differs from my prior patent in the addition of a discrete volume of high pressure fluid in biasing pressure reservoir 39 which is plumbed into the same manifold 14 as disclosed in my prior patent except for the addition in manifold 14 of a second pulse valve 41b. The dimensions and sizes of manifold 14 and the manifold conduits are the same as that used in my prior patent. Thus, the system has been modified to carry a highly pressurized source of fluid without dimensionally increasing the size of the standard components.
Referring next to FIG. 2, it will be noted that the drawing has been changed to include a timing circuit 35 which has been interposed between voltage comparator 58 and its driver 60. Timing circuit 35 could comprise any conventional timing circuit arrangement generating initially a first output 64b and then, after a short period of time in the neighborhood of about 600 milliseconds, generates a second output 64a while terminating first output 64b. A binary ripple counter CD4060 available from RCA Corporation could function for such a purpose. Driver 60 is unchanged from my prior patent and first output 64b is branched into two outputs 64b1 and 64b2 actuating, respectively, first pulse valve 41a and second pulse valve 41b. After the discrete time period of about 600 milliseconds, timing circuit 35 generates second output 64a while terminating first output 64b which is inputted into driver 60 and outputted therefrom to orificed standard deflation valve 34. Output 62 from comparator 58 is unchanged and actuates tire inflating valve 32 in the manner described in my parent patent. FIG. 2a shows the integration of pulse valves 41b, 41a and the high pressure biasing reservoir 39 into the electronic-pneumatic valving arrangement. Deleted from FIG. 2a for simplifying purposes is pressure responsive relief valve 44 which functions to open the system to atmosphere through vent 36 at a predetermined high pressure above which the tires are not to be inflated. The high pressure relief valve can be included in the system of the present invention by simply making the valve into a two position solenoid operated valve and integrating its operation into the electronic schematic shown so that the valve is cycled into its "off" position when pulse valves 41a, 41b are actuated and is in its "on" high pressure sensing position whenever the valves are not actuated. For drawing simplicity, high pressure relief valve 44 is not shown.
Referring now to FIGS. 4 and 5, FIG. 4 shows a plan view of a combination quick dump-isolating valve 309 similar to FIG. 7 of my parent patent. As best shown in FIG. 5, combination quick dump-isolating valve 309 has a valve housing 310 which incorporates tire isolating valve 18 and dump valve 312 of the present invention. More specifically, valve housing 310 has a first cylindrical chamber 314 containing the mechanism of dump valve 312 and a second cylindrical chamber 315 containing the poppet valve mechanism of tire isolation valve 18. The reader is referred to the parent patent for a detailed explanation of the operation of the poppet valve mechanism of isolating valve 18. Combination quick dump-isolating valve 309 has a biasing pressure inlet 317 adapted to be in communication with the fluid pressure source through the manifold 14 and a tire pressure inlet 318 adapted to be in fluid communication with the fluid in the tire T. Biasing pressure inlet 317 has a first biasing pressure inlet conduit 320 in fluid communication with one end of first cylindrical chamber 314 and a second biasing pressure inlet conduit 321 in fluid communication with one end of second cylindrical chamber 315. There is no pressure drop through the conduits 320, 321 and the pressure at first inlet conduit 320 is identical to the pressure at second inlet conduit 321. Similarly, tire pressure inlet 318 has a first tire pressure inlet conduit 323 in fluid communication with the opposite end of first cylindrical chamber 314 and a second tire pressure inlet conduit 324 in fluid communication with the opposite end of second cylindrical chamber 315. There is no pressure drop in either tire pressure conduit inlet 323, 324 and the pressure therein is identical to that existing in the tire T to which combination quick dump-isolating valve 309 is secured.
Axially spaced between first biasing pressure inlet conduit 320 and first tire pressure inlet conduit 323 is a large atmosphere outlet 326 in fluid communication with first cylindrical chamber 314. Disposed within first cylindrical chamber 314 is a quick dump piston or spool 328 having a first axial end face 330 in fluid communication with first biasing pressure inlet conduit 320 and, at its opposite end, a second axial end face 331 in fluid communication with first tire pressure inlet conduit 323. Piston 328 is axially movable in first cylindrical chamber 314, in part, by fluid under pressure acting on either first axial end face 330 from biasing pressure inlet 317 or tire fluid under pressure acting on second axial end face 331 through tire pressure inlet 318.
A biasing spring 333 engaging at one of its ends second axial end face 331 and at its other end, a shoulder 334 formed in first cylindrical chamber 314 provides a biasing force tending to move piston 328 towards the left as seen in FIG. 5 or in the "off" position of dump valve 312. As shown in FIG. 5, piston 328 is hollowed at its second axial end face 331 and has a plurality of circumferentially spaced, radially extending openings 336 drilled through piston 328. The interior of openings 336 are in fluid communication with tire fluid through tire pressure inlet 318 at all times. A pair of atmosphere O-ring seals 338, 339 straddle atmosphere outlet 326 to prevent the fluid from tire T communicating with atmosphere outlet 326 when dump valve 312 is at its "off" position. Piston 328 takes the shape of a solid cylindrical plug at its portion adjacent first axial end face 330 and an annular groove 340 is formed in piston 328 adjacent first axial end face 330.
As best shown in FIG. 5a, a detent mechanism 341 operates in conjunction with annular groove 340. Detent mechanism 341 includes a threaded hole 342 drilled into valve housing 310 which is in fluid communication with first cylindrical chamber 314 adjacent first biasing pressure inlet conduit 320. Inserted into threaded hole 342 is a ball detent 343 having a radius approximately equal to that of annular groove 340. Urging ball detent 343 into contact with piston 328 is detent spring 344, the compressive force of which is adjustable by slotted screw 345. Accordingly, dump valve 312 is adjusted by adjusting the position of slotted screw 345 in threaded hold 342 of detent mechanism 341. A pair of detent O-ring seals 350, 351 straddle detent mechanism 341 to prevent leakage of fluid to threaded hole 342. It is preferred that a pair of atmosphere O-ring seals 338, 339 and a pair of detent O-ring seals 350, 351 be used instead of a three O-ring seal arrangement. Using 4 O-ring seals as shown provide a better balanced or more responsive valve instead of a three O-ring seal arrangement by avoiding any possibility of a differential pressure acting on the intermediate seal.
In the unactuated or "off" position of dump valve 312 as shown in FIG. 5, detent mechanism 341 is not in contact with annular groove 340 and is thus disengaged. Further, openings 336 are not in fluid communication with atmosphere outlet 326. Thus, there is a system pressure force from biasing pressure inlet 317 acting on first axial end face 330 of piston 328 tending to move piston 328 towards it unactuated position or towards the right as viewed in FIG. 5. This force, whatever it might be, is resisted by the force of the fluid from tire T acting on second axial end face 331 which acts to move piston 328 towards the unactuated position or the left as viewed in FIG. 5. To this tire pressure force is added the mechanical force of biasing spring 333 which is always acting to shift piston 328 towards its unactuated position. When the fluid pressure at biasing pressure inlet 317 becomes great enough to overcome the force of biasing spring 333 and the force developed by fluid from tire T, piston 328 will shift towards the right as viewed in FIG. 5 to its actuated position. (As already indicated, fluid at system pressure, i.e. 70-80 psi, will not be sufficient to shift piston 328, but fluid at the biasing pressure, i.e. 110-120 psi, will move piston 328.) In the actuated position of dump valve 312, ball detent 343 engages annular groove 340 and openings 336 are in fluid communication with atmosphere outlet 326. Thus, in the open or actuated position of dump valve 312, the biasing force developed by the tire pressure fluid is no longer operative against second axial end face 331 to shift piston 328 towards its unactuated position. The only force acting to shift piston 328 towards its off position is biasing spring 333 and the force of biasing spring 333 is resisted by first, the mechanical force exerted by ball detent 343 engaged in annular groove 340 and which must be dislodged before piston 328 can return to its "off" position and secondly, the force developed by system pressure at biasing pressure inlet 317 acting on first axial end face 330. When the biasing pressure fluid force drops below a predetermined level, the mechanical force of biasing spring 333 will overcome the mechanical force exerted by detent mechanism 341 and shift piston 328 towards its unactuated position. As soon as openings 336 clear atmosphere outlet 326, the force from the fluid at tire pressure will add to the force of biasing spring 333 to insure quick closure of piston 328 to its actuated position. It should be noted then that detent mechanism 341 is providing an instantaneous "on/off" open/closure action to quick dump valve 312. That is, system pressure is used to actuate the valve from its "off" to its "on" position at which time detent mechanism 341 is instantaneously engaged to lock dump valve 312 into its "on" position. Simultaneously, when the biasing pressure fluid drops to a predetermined value (i.e. when manifold pressure drops to zero as it is ported through exhaust valve 38) detent mechanism 341 is instantaneously disengaged and quick dump valve 312 rapidly and firmly moves to its unactuated or "off" position. Thus, a "snap-action" operation is obtained. Additionally, a counterbalancing mechanical spring arrangement is utilized to permit quick dump valve 312 to be sensitive to operation only from the pressure of the fluid developed by the system.
OPERATION
The operation of the system will now be explained only with respect to its discharge mode. The reader is referred to the parent patent for operation of the system for pressure checking and inflation since the system has not been changed with respect to such functions. In the discharge mode, the tires are at some predetermined pressure, i.e. highway at 60 psi, cross country at 35 psi or mud/snow/sand at 25 psi and the vehicular operator actuates the system from electronic control module 10 by manually moving pressure selector component 20 to the desired deflation level and depressing start button 24. For definitional purposes, the numeral 14 means the manifold and includes all the valving and associated manifold conduits needed to operate the system. The electronic module 10 in combination with manifold 14 comprises the electronic-pneumatic valving arrangement necessary to operate the system from an external air supply source 16 which includes high pressure reservoir 39. Within manifold 14, there are a number of manifold lines but there is one principal manifold line designated by numerals 118, 116 and 117 which remains in fluid communication with combination quick dump-isolating valve 309.
As best shown in FIG. 3, when the operator actuates the deflation mode of the system, comparator 58 generates a signal 64 which is timed through timing circuit 35 to generate, for a discrete time of about 600 milliseconds, a signal 64b which is split into signals 64b1 and 64b2 to simultaneously actuate pulse valves 41a and 41b. At this time, fluid from high pressure reservoir 39 is discharged through first pulse valve 41a into air supply line 15 and thence through second pulse valve 41b into main conduit 117, 116 and 118 and shocks dump valve 312 isolating valve 309 into their open positions. At this time, exhaust valve 38, tire inflating valve 32 and preliminary control valve 28 are closed. Also shown closed is standard deflating valve 34. Thus, for a very short period of time, 600 milliseconds or so, the system is sealed from atmosphere and is shocked into an actuating position. At the end of the 600 millisecond time, timing circuit 35 generates signal 64a which actuates standard deflating valve 34 into its orificed "on" position which immediately and almost instantaneously in conjunction with the isolation valve 309 dissipates the shock the system received from high pressure biasing source reservoir 39 so that the other valves in the system and the manifold lines do not need to be increased in size or otherwise strengthened because of the high pressure from reservoir 39. At this point in time, fluid from each tire T is rapidly escaping to atmosphere through atmosphere outlet 326 of dump valve 312 and simultaneously, fluid is also escaping, at a controlled rate, from tire isolating valve 18 through the orifice of standard deflation valve 34 to atmosphere. Transducer 46 is now sensing tire pressure by pressure within manifold 14 to actuate the system in the same manner as described in my prior patent. Specifically, the flow of fluid from tire T through standard deflating valve 34 is creating a back pressure continuously monitored by transducer 46 and correlated through the electronic circuitry to the tire pressure. When the tire pressure drops to whatever pressure level is dictated by controller 20, the system will automatically switch tire deflating valve 34 to its "off" position and actuate exhaust valve 38 to quickly dump the fluid in the manifold to atmosphere through conduit 36. This will drop the pressure of the fluid in biasing pressure inlet 317 almost immediately to zero and force tire isolating valve 18 to its closed position and simultaneously therewith close dump valve 312 in the manner described above.
The valving of the present invention does not affect the operation of the tire pressure system during the inflation mode or the pressure checking mode because first and second pulse valves 41a, 41b are actuated only in the discharge mode. Thus, in all other instances, the pressure delivered to combination quick dump-isolating valve 309 does not exceed the normal system pressure of about 70-80 psi and this pressure, while sufficient to operate tire isolating valve 18 as described in my parent patent, is insufficient to actuate dump valve 312.
The invention has been described with reference to a preferred embodiment. Obviously, alterations and modifications will occur to others skilled in the art upon reading and understanding the specifications. For example, dump valve 312 has been shown to be always engaged whenever a discharge mode is required. The system can be easily modified so that pulse valves 41a, 41b will only be actuated when the operator places the tire pressure system into the emergency mode and the other modes could be utilized in the manner described in the parent patent which will permit a somewhat rapid but more slower deflation of the tires than that disclosed herein. Also, the term "fluid" has been used throughout with reference to a description of a pneumatic system because the concepts disclosed herein could be used in any gaseous system and, conceptually, in systems where the tires are filled with liquid under pressure, in which instance, the system would be modified to include reservoirs and return lines. It is my intention to include all such modifications and alterations insofar as they come within the scope of the present invention.
It is thus the essence of my invention to provide a vehicular tire pressure system which utilizes system and tire pressure to rapidly exhaust tire pressure in a very accurate and controllable manner. | A system for inflating and deflating pneumatic tires of a vehicle through pneumatically actuated tire isolating valves is disclosed which isolates air under pressure in the tires from the system and which utilizes electronically controlled valves for achieving opening of the tire isolating valves and inflating, deflating or eluding the pressure. The system is improved by incorporation of a dump valve at each tire which permits rapid deflation of the tire pressure upon demand. The dump valve is tire and system pressure responsive and is integrated into the system in a manner to be responsive to any number of deflated tire pressures. | 1 |
RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 11/717,651, filed on Mar. 14, 2007, claiming priority of Japanese Patent Application No. 2006-068479, filed Mar. 14, 2006, the entire contents of each of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to an inspection method and inspecting apparatus, particularly to a technology suitable for inspecting the generation state of a defect such as a particle etc. in a manufacturing process by inspecting a defect such as a particle etc. produced in the manufacturing process for forming a pattern on a substrate to manufacture an object, such as a semiconductor manufacturing process, a liquid display element manufacturing process, and a printed circuit board manufacturing process, analyzing and taking measures.
[0003] In a semiconductor manufacturing process, a particle on a semiconductor substrate (wafer) may cause a failure such as an insulation failure or shot-circuit. Further, as semiconductor elements become miniaturized, if a microscopic particle is present, the microscopic particle may cause an insulation failure of a capacitor or breakdown of a gate oxide film. Such a particle comes to be mixed in, with taking various forms such as a particle produced from a moving part of a carrier device or a human body, a matter created by reaction of a process gas in a processing device, and a matter which is a chemical or a material mixing in.
[0004] Similarly, also in a liquid display element manufacturing process, if adherence of a particle to a pattern formed on a substrate of a liquid display element or any defects on the pattern occur, the substrate can not be used as a display element. Also, the same goes for a printed circuit board manufacturing process, and adherence of a particle may cause a short-circuit and insufficient connection on a pattern.
[0005] Conventionally, there is one technology, as disclosed in JP-A-62-89336, for detecting a particle on a semiconductor substrate of this type in which a laser beam is projected onto a semiconductor substrate to detect scattered light generated from a particle when the particle adheres to the semiconductor substrate and the detected light is compared with the inspection result obtained the adjacent inspection of a semiconductor substrate of the same product class, which eliminates disinformation from patterns and enables highly-sensitive and highly-reliable inspection of a particle and defect. Further, as disclosed in JP-A-63-135848, there is a technology in that a laser beam is projected onto a semiconductor substrate to detect scattered light generated from a particle when the particle adheres to the semiconductor substrate and the detected particle is analyzed by an analyzing technology such as laser photoluminescence or two dimension X-ray and Magnetic Resonance imaging (XMR) analysis.
[0006] Further, for a technology of inspecting such a particle as the above, a method is disclosed that a wafer is irradiated with coherent light and diffracted light produced from a repeating pattern on the wafer is removed by a spatial filter, thus the particle or defect without repeatability is highlighted to be detected. Further, a particle inspecting device is disclosed in JP-A-1-117024 in which a circuit pattern formed on a wafer is irradiated from the direction tilted at 45° to a group of main straight lines on the same pattern to prevent zero-order diffracted light from the group of main straight lines from entering the opening of an objective lens. In JP-A-1-117024, it is also described that the other group of straight lines other than the main straight lines are light-shielded by a spatial filter. Further, a conventional technology concerning a defect inspecting apparatus of a defect such as a particle etc. and a method thereof is disclosed in JP-A-2000-105203 in that a detection pixel size is changed by switching a detection optical system. A technology for measuring the size of a particle is disclosed in JP-A-2001-60607 and No. 2001-264264. JP-A-2004-177284 discloses a technology for detecting a defect on a thin film in that a laser beam is narrowed down to form a beam spot which is elongated in the direction perpendicular to a stage moving direction, and detection is performed in the direction perpendicular to an illumination direction.
BRIEF SUMMARY OF THE INVENTION
[0007] In the cases of JP-A-63-135848, No. 1-117024 and No. 2000-105203, the defect detection sensitivity fluctuates owing to changes in temperature or barometric pressure at a location where the defect inspecting apparatus is installed and sensitivity calibration frequency tends to increase due to the following reasons, improving deterioration in an operating rate of the apparatus due to frequent calibration is a challenge.
[0008] To detect a microscopic defect in the process of a recent, miniaturized semiconductor, in a defect inspecting apparatus, the SN of a defect signal strength is enhanced by reduction in a detection pixel size. The reduction in the detection pixel size makes the focal depth of a detection optical system shallow, therefore the relative refractive index of a detection lens is changed and a body tube is expanded thermally owing to fine changes in temperature or barometric pressure, thus the height of imaging of a defect is displaced, accordingly the image defocuses to decrease detection sensitivity. A clean room in which a defect inspecting apparatus is installed often provides an insufficient distance from adjacent equipment or a wall, and a local temperature in the environment of installation may change in about an hour. Keeping the detection sensitivity needs sensitivity calibration, but more frequent calibration may lower the operating rate of the apparatus because one calibration requires several minutes. For measures against it, there is a method of installing an apparatus in a dedicated thermal chamber, but because of disadvantages that the apparatus may be expensive and a footprint may be enlarged, this method is not suitable for a defect inspecting apparatus. Further, on the one hand, because barometric pressure in a clean room is not controlled, the sensitivity may become unstable when a low or high atmospheric pressure passes.
[0009] An object of the present invention is, to solve the above problems, to provide a defect inspecting apparatus configured so that a height of imaging can be corrected in real time for changes in temperature and barometric pressure.
[0010] To achieve the above object, in the invention, a mechanism in which a change in temperature or barometric pressure decreases the sensitivity was studied and measures against it were devised. More specifically, the mechanism is such that temperature and barometric pressure at a location of installation of the defect inspecting apparatus may have deviation from temperature and barometric pressure under which the sensitivity was adjusted up to a maximum in the same conditions and accordingly a height of imaging of a defect varies, and therefore measures are that a defect inspecting apparatus is provided which includes a construction for correcting the height of an object surface or image surface in real time for a change in at least either temperature or barometric pressure so that the image of an inspected substrate formed on an image sensor by a detection lens does not defocus. That is, a temperature of an inspection lens and a barometric pressure near the inspection lens are measured and a height of imaging for correction, or a height of the inspected substrate for correction when a sensor height is fixed, is derived from their deviation values, then after correction, inspection is carried out. The correction value is read out from a data table before inspection, which is created in advance from relation between temperature and barometric pressure, and the height of imaging, which is obtained in adjustment of the defect inspecting apparatus.
[Mechanism of Sensitivity Decrease Due to Change in Barometric Pressure]
[0011] A mechanism of the sensitivity decrease when barometric pressure falls is as follows. When barometric pressure falls, air density becomes small (proportionality relation), and therefore a relative refractive index of a detection lens becomes large and a focal length of the detection lens becomes small. As the result, a height of imaging becomes small, resulting in defocus and decrease in sensitivity. When barometric pressure rises, a mechanism is opposite to the falling case, the height of imaging becomes large, resulting in defocus and decrease in sensitivity. The height of an inspected substrate in relation to change in barometric pressure will be described with reference to FIG. 3 . Plotted in the figure are heights of the inspected substrate at which the image of a defect does not defocus when an image sensor is fixed and barometric pressure in an apparatus changes. In the relation between the barometric pressure and the heights of the inspected substrate, the height of the inspected substrate changes linearly, because the relative refractive index between air and a lens is a linear function of barometric pressure. A shift ΔZ of a height of imaging when barometric pressure changes will be described with reference to FIG. 4 . In imaging relation, an object surface is comprised of the inspected substrate 1 , a lens is comprised of an upper detection optical system 200 and an imaging surface is comprised of an image sensor 205 , and when barometric pressure rises, a focal length of the lens becomes large. Therefore, when a height of the image sensor is fixed, the height of the inspected substrate 1 may be lowered by −ΔZ to bring focus on the image sensor. On the contrary, when the inspected substrate 1 is fixed, it is necessary to raise the height of the image sensor by a longitudinal magnification of the detection lens, i.e. ΔZ× the magnification 2 .
[Mechanism of Sensitivity Decrease Due to Change in Temperature]
[0012] A mechanism of sensitivity decrease when temperature falls is as follows. When temperature falls, air density becomes large (proportionality relation), and therefore a relative refractive index of a lens becomes small and a focal length becomes large. As the result, a height of imaging becomes large, resulting in defocus and decrease in sensitivity. When temperature rises, a mechanism is opposite to the falling case, and the height of imaging becomes small to cause defocus of the image of a defect, resulting in sensitivity decrease. In addition, change in temperature has influence on elongation of a detection lens body tube, and the height of imaging varies complicatedly. For example, when temperature falls, a length of the lens body tube becomes small due to thermal expansion, and as the result, unless a position of the object surface is raised, the height of imaging defocuses to decrease the sensitivity.
[0000] [Data about Relation Between Temperature and Barometric Pressure, and a Height of an Object Surface or an Image Surface]
[0013] Using as a reference point standard environment which is regulated to, for example, 23° C. and 1,013 hPa and the height of an object surface or an image surface at which an image does not defocus under the environment, that is, the height of the object surface or the image surface having the maximal sensitivity under certain optical conditions, there is determined relation between barometric pressure and temperature measurements with respect to the reference point and a deviation of the height of the object surface or image surface at which imaging does not defocus when an environmental temperature at a location of installation of a defect inspecting apparatus is changed in a positive manner in adjustment, or when the environment changes. A data table for it will be described with reference to FIG. 5 . Under the same optical conditions, i.e. the same detection magnification, the same illumination condition, the same substrate under test (a standard wafer for confirming sensitivity) and when a temperature at the location of installation of the defect inspecting apparatus is changed by ±2° C., a height of the inspected substrate Z at which the maximal sensitivity (maximal signal strength) may be obtained is found. The standard wafer for confirming sensitivity may be desirably, for example, a substrate formed by applying evenly particles of PSL uniform in size onto a silicon substrate. The height of the substrate Z is plotted by 1 μm in a graph in which the ordinate axis represents barometric pressure and the abscissa axis represents temperature. In this example, the height of the substrate Z is in the unit of 1 μm, but a focal depth of a detection optical system may be desirably used as a minimal unit.
[0014] Because barometric pressure is proportional to gas density owing to a state equation, the height of the substrate approximately conforms to simulated data obtained from tracking a beam of light with barometric pressure being varied in an optical imaging simulator. Therefore, the simulated data as shown in FIG. 3 may be desirably used as data to create the data shown in FIG. 5 .
[Correction Method]
[0015] Since temperature and barometric pressure are measured before inspection and a height of imaging or a position of an image sensor, i.e. a correction value for a height of an object surface or image surface corresponding to the temperature and barometric pressure is read from FIG. 5 to correct the height of the object surface or image surface to inspect, an operator can inspect not knowingly at a maximal sensitivity under selected optical conditions. Needless to say, without using the absolute data table in which the reference point is set as described above, it is also possible that a coefficient is derived in advance from relation between temperature and barometric pressure, and the height of the object surface or image surface, and then a correction value for the height of the object surface or image surface may be computed and obtained relatively by multiplying a deviation between two points of the temperature and barometric pressure with the coefficient.
[0016] More specifically, in a block diagram shown in FIG. 12 , a control CPU portion 401 stores a Z coordinate (Z reference value) at which the maximal sensitivity is provided, a barometric pressure at that time (barometric pressure reference value), a temperature (temperature reference value) at that time, a coefficient obtained in advance for converting a barometric pressure into the Z coordinate (barometric pressure coefficient) and a coefficient for converting a temperature into the Z coordinate (temperature coefficient).
[0017] For correction of change in barometric pressure, a Z correction value is derived by adding a Z conversion value of barometric pressure for the change to a variation to the Z reference value, which Z conversion value is obtained by computing a difference between a measurement value by a barometric pressure measure 504 at an arbitrary time and the barometric pressure reference value and by multiplying it by the barometric pressure coefficient.
[0018] For correction of change in temperature, the Z correction value is derived by adding a Z conversion value of temperature for the change to a variation to the Z reference value, which Z conversion value is obtained by computing a difference between a measurement value by a temperature measure at an arbitrary time and the temperature reference value and by multiplying it by the temperature coefficient. Because the correction of change in barometric pressure and the correction of change in temperature function independently from each other, the Z correction value may be obtained by adding both of the Z conversion value based on barometric pressure and the Z conversion value based on temperature to the Z reference value, and by this correction value, concurrent correction of barometric pressure and temperature can be performed. A Z stage control unit 305 can locate a height of the inspected substrate at which the maximal sensitivity is provided, by changing a height of the Z stage 303 by the Z correction value.
[0019] As described above, the invention enables highly-sensitive detection of a defect wherein focal depth becomes shallow while stabilizing the sensitivity without lowering of the operating rate by calibration.
[0020] The invention is effective for change in the environment, and because the inspection lens and the environment change near the lens are measured, further countermeasures can be made against change in a temperature of an inspection lens caused by a local heat produced in the apparatus, such as a driving system of an inspection XY stage, a light source, sensors, controllers etc.
[0021] When the invention is applied, a thermostatic chamber is not required as measures for change in temperature, and therefore a size, cost and requirement for environment of equipment can be reduced.
[0022] The above features and other features than the above of the invention will be now described hereinafter. Other objects, features and advantages of the invention will become apparent from the following description of embodiments of the invention in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0023] FIG. 1 is view illustrating system configuration of a defect inspecting apparatus.
[0024] FIG. 2 is a view illustrating the configuration of a system according to the invention.
[0025] FIG. 3 is a graph showing relation between barometric pressure and the height of an inspected substrate in focus.
[0026] FIG. 4 is a view explaining that the height of an inspected substrate is varied by change in barometric pressure.
[0027] FIG. 5 is a graph of relation between temperature and barometric pressure and a correction amount for the height of an inspected substrate.
[0028] FIG. 6 is a view for explanation of a spot formed by illuminating a projection plane of an image sensor on an inspected substrate from three directions.
[0029] FIG. 7 is a view illustrating an inspected substrate on which memory LSIs, i.e. samples to be inspected, are arranged.
[0030] FIG. 8 is a view illustrating an inspected substrate on which LSIs such as microcomputers etc., i.e. samples to be inspected, are arranged.
[0031] FIG. 9 is a view illustrating an optical system, including an illumination lens of an illumination optical system, of the defect inspecting apparatus according to the invention.
[0032] FIG. 10 is a view illustrating the function of the illumination lens of the illumination optical system in the defect inspecting apparatus according to the invention.
[0033] FIG. 11 is a view for explanation of an illumination optical system.
[0034] FIG. 12 is a schematic view illustrating the principle of the invention that the height of a Z stage is corrected by using a coefficient of a conversion formula.
DESCRIPTION OF REFERENCE CHARACTERS
[0000]
1 —Inspected Substrate (Wafer),
2 —Chip,
3 —Slit-Like Beam (Illumination Region),
4 —Detection Region of Image Sensor such as TDI Sensor,
100 —Illumination Optical System
101 —Laser Source,
102 —Concave Lens,
103 —Convex Lens,
104 —ND Filter,
110 —0-degree Illumination Beam Spot Imaging Portion
120 —45-degree Illumination Beam Spot Imaging Portion (direction 10 ),
130 —45-degree Illumination Beam Spot Imaging Portion (direction 11 ),
200 —Vertical Detection Optical System,
201 —Objective Lens (Detection Lens),
202 —Spatial Filter,
203 —Imaging Lens,
204 —Zoom Lens Group,
205 —One-Dimensional Detector such as TDI Sensor,
206 —Sensor Z Driving System,
300 —Stage System,
301 - 304 —XYZθ Stage,
305 —Stage Control,
400 —A Control System,
401 —Control CPU Portion,
402 —Signal Processing Portion,
403 —Display Portion,
404 —Input Portion,
500 —Oblique Detection System
501 —Automatic Focus Unit,
502 —Signal Processing Circuit,
503 —Temperature Measure,
504 —Barometric Pressure Measure.
DETAILED DESCRIPTION OF THE INVENTION
[0067] Embodiments of the invention will be described hereinafter with reference to the drawings. In the following drawings, similar functional portions are denoted by the same reference signs.
[0068] First, a substrate 1 to be inspected for a defect such as a particle etc. according to the invention will be described with reference to FIGS. 7 and 8 . Since the details are described in Japanese Patent No. 3566589, the summary will be provided.
[0069] The substrate 1 to be inspected for a defect such as a particle etc. may be, as shown in FIG. 7 , a semiconductor wafer 1 a on which chips 1 aa comprised of memory LSIs are arrayed two-dimensionally at predetermined intervals. The chip 1 aa comprised of the memory LSI is mainly formed with a memory cell region lab, a peripheral circuit region 1 ac comprised of a decoder, a control circuit and the like, and another region lad. The memory cell region lab is formed by arraying (repeatedly) a memory cell pattern two-dimensionally and regularly. However, the peripheral circuit region 1 ac is formed by arraying a pattern two-dimensionally, but not regularly and repeatedly.
[0070] The substrate 1 to be inspected for a defect such as a particle etc. may be, as shown in FIG. 8 , a semiconductor wafer 1 b on which chips 1 ba comprised of LSIs such as microcomputers etc. are arrayed two-dimensionally at predetermined intervals. The chip 1 ba comprised of the LSI such as a microcomputer etc. is mainly formed of a register group region 1 bb , a memory region 1 bc , a CPU core region 1 bd and an input/output region 1 be . Incidentally, FIG. 8 conceptually shows the array of the memory region 1 bc , the CPU core region 1 bd and the input/output region 1 be . The register group region 1 bb and the memory region 1 bc are formed by arranging patterns two-dimensionally and regularly (repeatedly). The CPU core region 1 bd and the input/output region 1 be are formed by arranging nonrepeating patterns. As described above, as for the inspected substrate 1 to be inspected for a defect such as a particle etc., even when a semiconductor wafer is addressed, although the chips are arranged regularly, in the chip, a minimal line width is different in each region, and further it is considered that there may be various arrangements such as a repeating pattern, nonrepeating pattern and the like.
[0071] The defect inspecting apparatus of a particle etc. and a method thereof according to the invention are based on an apparatus that in such an inspected substrate 1 as above, zero-order diffracted light produced from a pattern (linear pattern) comprised of a group of lines on a nonrepeating pattern region in the chip is blocked to enter an entrance pupil of an objective lens and scattered light produced by a defect such as a particle etc. present on the nonrepeating pattern region is received, thereby allowing a signal caused from the defect such as a particle etc. to be detected and a position coordinate of the defect to be computed. The details are described for instance in Japanese Patent No. 3566589 (particularly, see paragraphs 0033 to 0036), and here the explanation will be omitted.
[0072] Next, a first embodiment of the defect inspecting apparatus according to the invention will be described with reference to FIG. 1 .
[0073] The first embodiment of the defect inspecting apparatus includes: a stage portion 300 composed of an X stage 301 , Y stage 302 , Z stage 303 capable of focusing on a surface of an inspected substrate, theta (θ) stage 304 and stage controller 305 ; a laser source 101 ; a concave lens 102 ; and a convex lens 103 . The apparatus further includes: an illumination optical system 100 comprising a beam expander, a beam formation portion composed of an optical filter group 104 and a mirror 105 , and three sets of a beam spot imaging portion composed of a transparent glass plate and a switchable optical branching element (or a mirror) 106 , an illumination lens with a cylindrical curved surface 107 and mirrors 108 , 109 ; a detection optical system comprising a detection lens 201 , a spatial filter 202 , an imaging lens 203 , a zoom lens group 204 and a one-dimensional sensor (image sensor) 205 such as TDI etc.; an optical system 500 comprising a lens and a sensor for detection at a low elevation angle; a control system 400 comprising a signal processing system 402 composed of an A/D conversion portion, a data memory which may be delayed, a difference processing circuit for obtaining a difference between signals of chips, a memory for storing temporarily a difference signal between the signals of the chips, a threshold computation processing portion for setting a pattern threshold and a comparison circuit, an output means for storing a detection result of a defect such as a particle etc. and outputting the detection result of a defect, a computation processing system 401 for controlling driving of a motor etc., a coordinate and an image sensor, a display system 403 , and an input system 404 . The defect inspecting apparatus is on the system that a defect on the inspected substrate is illuminated at a slant, the inspected substrate which is mounted on the XY stage is scanned in a predetermined direction and light generated by the defect is received by the detection optical system disposed on the upper side, and the apparatus is characterized by including a mechanism which corrects a height of imaging in real time for change in temperature and barometric pressure so that an image does not defocus. The detection optical system 200 disposed on the upper side described above can detect a more microscopic defect and a defect equal to or smaller than a limit value of resolving power, by including a magnifying lens to receive scattered light from the defect with a high NA, and magnifying and projecting it with a high magnification on the image sensor to inspect in a small pixel size.
[0074] A unit according to the invention will be described using FIG. 2 . The unit includes: an automatic focus system 501 having a position sensor and an imaging light path of off-axis for projecting and receiving a light beam which dose not pass through a lens in the detection lens 201 ; a signal processing circuit 502 ; the X stage 301 , the Z stage 303 as a stage Z mechanism for controlling the height of the inspected substrate to correct the height of an object surface; the stage control system 305 ; the image sensor 205 ; the image sensor Z-direction driving system 206 as a Z mechanism for moving up and down the image sensor to correct the height of imaging; the control CPU portion 401 ; a barometric pressure measure 504 ; and a temperature measure 503 . The control CPU portion 401 , the stage control system 305 and the signal processing circuit 502 form a control system for converting a deviation of at least either temperature or barometric pressure into a correction value for the position of an object surface or image surface and for locating the object surface or image surface, and can drive the image sensor Z-direction driving system 206 or the Z stage 303 to correct the height of the object surface or image surface in real time for change in at least either temperature or barometric pressure so that an image of the inspected substrate formed on the image sensor by the detection lens does not defocus. As for measurement of temperature and barometric pressure, in order to reduce an error due to a gradient of temperature and barometric pressure, it is desirable to attach a sensor portion so that the inside or the surface of the detection lens 201 can be measured. A result measured by the barometric pressure measure 504 and the temperature measure 503 is sent to the control CPU portion 401 , a correction value ΔZ is read out based on a data table prepared from the graph of FIG. 5 described above, and then a command as an offset value is sent to the signal processing circuit 502 . The signal processing circuit 502 drives the stage Z in a closed loop until the offset value corresponding to the correction value ΔZ is provided by the automatic focus system 501 . When the height of the inspected substrate is corrected, a spot 3 of a separate illumination system is displaced separately, and therefore it becomes necessary to have a function for correcting automatically the position of the spot 3 to the center.
[0075] In this embodiment, also by using the image sensor Z-direction driving system 206 and by relatively moving a value of ΔZ× magnification 2 , a height of the image sensor 205 may be varied so that the image sensor can be located at a height of imaging displaced due to temperature or barometric pressure and imaging with no defocus can be obtained. Autofocusing illumination light is configured in a manner that it has an illumination path in a space which does not interfere with the detection lens, and illuminates the inspected substrate to provide dark-field illumination, and reflected light provides an image on an opposite position sensor. The autofocusing system uses desirably a light source having a wideband wavelength for preventing the light from interfering with a pattern of a particular film thickness on the inspected substrate to lower signal strength. On the one hand, the detection lens is designed to bring out an imaging performance to a diffraction limit at a single, inspection illumination wavelength, and therefore when the autofocusing light path is designed to be shared with the detection lens, the lens becomes expensive largely. Particularly, when a detection illumination wavelength is short and has a large difference from an autofocusing illumination wavelength, it is difficult to design the lens and an off-axis specification may be desirably applied.
[0076] The three illumination optical systems 100 are configured in a manner that a light beam emitted from the laser source 101 passes through the beam expander composed of the concave lens 102 and the convex lens 103 , and through the illumination lens 107 having a cylindrical curved surface so that a slit-like beam 3 irradiates the substrate (wafer) 1 to be inspected from three directions 10 , 11 and 12 in a plane as shown in FIG. 6 with the longitudinal direction of the slit-like beam 3 facing the array direction of the chips. The array direction of the chips corresponds to a detection region 4 of the sensor. Incidentally, the reason why the slit-like beam 3 is used as the illumination light is that a scan width large in the X direction is made large and inspection of a defect such as a particle etc. is sped up. Further, the slit-like beam 3 from the three directions 10 , 11 , 12 may irradiate the substrate selectively from one direction or two directions 10 , 12 concurrently by switching a beam splitter or the mirror 106 to a transparent glass plate of the same thickness. The longitudinal direction of the slit-like beam 3 is turned toward the array direction of the chips with respect to the inspected substrate 1 and perpendicular to a scan direction Y of the Y stage 302 . This allows simplifying comparison of a pixel signal between the chips and facilitating computation of a position coordinate of a defect, thereby speeding up inspection of a defect such as a particle etc.
[0077] FIGS. 9 , 10 show an illumination lens 104 having a circular cone shape and a cylindrical curved surface. A manufacturing method etc. of the illumination lens 104 having the cylindrical curved surface is described in detail, for example, in Japanese Patent No. 3566589 (particularly, see paragraphs 0027 and 0028) and it may be manufactured by the known method. The illumination lens 104 of a circular cone shape is a lens having different focal lengths at positions in the longitudinal direction of a cylindrical lens, which lengths are varied linearly. With this configuration, even when illumination is provided at a slant (having tilts φ 1 , α 1 ) as shown in FIG. 10 , the slit-like beam 3 narrowed down in the Y direction and collimated in the X direction can irradiate. That is, according to this illumination lens 104 , illumination having a collimated light beam in the X direction can be provided at near φ 1 =45°, as shown in FIG. 9( a ). Especially, as shown in FIG. 9( a ), the slit-like beam 3 is collimated in the X direction, and accordingly a diffracted light pattern can be obtained from a circuit pattern having a main group of lines facing the X or Y direction and be light-shielded by the spatial filter 202 .
[0078] The illumination lens 104 having the cylindrical curved surface can form the slit-like beam 3 shown in FIG. 10 .
[0079] FIG. 11 is a plan view illustrating the illumination optical system 100 having the three beam spot imaging portions in FIG. 1 . A laser beam emitted from the laser source 101 is branched into two light paths by a branching optical element 110 such as a half mirror etc., and one of the branched beams is reflected by mirrors 111 , 112 and turned downward by a mirror 113 to enter the concave lens 102 , thereby providing an illumination beam from the direction 11 , and the other beam progresses to a branching optical element 114 such as a half mirror etc. One branched by the branching optical element 114 is reflected by a mirror 115 and turned downward by a mirror 117 to enter the concave lens 102 , thereby providing an illumination beam from the direction 10 , and the other is turned downward by a mirror 116 to enter the concave lens 102 , providing an illumination beam from the direction 10 . By the way, illumination only from the direction 11 can be provided by switching the branching optical element 110 to a mirror element 118 . Also, illumination only from the directions 10 and 12 can be provided by removing the branching optical element 110 from the light path or by switching it to a transparent optical element. Further, illumination only from for example, the direction 12 selected from the two directions 10 and 12 can be provided by switching the branching optical element 114 to a mirror element 119 .
[0080] Besides, for the laser source 101 , the third higher harmonic wave THG of a high-power YAG laser with a wavelength of 355 nm may be used because of branching, but it is not necessarily limited to 355 nm. Also, the laser source 101 is not necessarily of YAG THG. That is, the laser source 101 may be another laser source such as an Ar laser, nitrogen laser, He—Cd laser, excimer laser and the like.
[0081] The detection optical system 200 is configured in a manner that light outgoing from the wafer 1 is detected by using the detection lens (objective lens) 201 , the spatial filter 202 for light-shielding a Fourier transform image out of reflected, diffracted light from a repeating pattern, the imaging lens 203 , and the one-dimensional sensor 205 such as TDI etc. The spatial filter 202 is disposed at a height of imaging in a spatial frequency region of the objective lens 201 , i.e. a Fourier transform (corresponding to a projecting pupil) in order to light-shield the Fourier transform image out of the reflected, diffracted light from the repeating pattern. Here, an image of an illumination area 3 on the wafer 1 shown in FIG. 7 is formed on the image sensor 205 by the object lens 201 and imaging lens 203 constituting a relay lens. A light-receiving area of the one-dimensional sensor 205 such as TDI etc. is denoted by 4 .
[0082] When the inspected substrate 1 having the circuit patterns of various forms formed thereon as described above is irradiated with the slit-like beam 3 , the reflected, diffracted light (or scattered light) is projected from the surface of the wafer, the circuit patterns, and a defect such as a particle. This projected light is received by the image sensor 205 through the detection lens 201 , spatial filter 202 and imaging lens 203 and is converted photoelectrically. In illuminance (power) of light beam flux emitted from the illumination optical system such as the laser source 101 etc., its dynamic range may be changed by controlling a ND filter 104 or laser power to change.
[0083] Further, the inspected substrate (wafer) 1 has to be inspected for a particle or a defect, the residue after etching and the like intruding in a concave portion between wires etc. However, because the nonrepeating pattern is present on the inspected substrate 1 , in order to prevent zero-order diffracted light from the nonrepeating pattern from entering the objective lens 201 , as described above, the substrate 1 is irradiated with the slit-like beam 3 arranging its longitudinal direction in the X direction from the directions 10 , 12 which forms an angle of about 45° to the Y axis. This makes it difficult to irradiate the concave portion sufficiently, because the wires etc. form convex portions and block the slit-like beam 3 .
[0084] Then, since a wiring pattern is often formed in the perpendicular and parallel direction, the substrate 1 may be irradiated with the slit-like beam 3 from the direction 11 parallel to the Y axis, which allows the concave portion between wires etc. to be sufficiently irradiated. Particularly, a wiring pattern of a memory LSI is often a linear pattern having a length of several mm, therefore illumination from this direction 11 may allow often inspection.
[0085] Also, depending on a pattern, when in the direction of 90°, rotating the wafer by 90°, or setting the illumination direction to the X direction allows inspection.
[0086] Next, the spatial filter 202 will be described. The chip 2 includes a repeating pattern such as the memory cell region lab in the memory LSI 1 aa , the register group region 1 bb in the LSI 1 ba such as a microcomputer etc., and the memory region 1 bc , and it is required to light-shield a diffracted light pattern (diffraction interference pattern) generated from this repeating pattern by the spatial filter 202 . In a word, a repeating pattern, nonrepeating pattern and absence of a pattern are mixed on the chip 2 and moreover a line width is different from each other. Therefore a light-shielding pattern of the spatial filter 202 is usually set so that diffracted light from, for example, a repeating pattern which frequently appears is eliminated. Further, when a spatial filter 202 with a variable light-shielding pattern as described in JP-A-5-218163 and No. 6-258239 is used, it may be changed depending on a circuit pattern in the chip 2 . Alternately, spatial filters of different light-shielding patterns may be provided as the spatial filter 202 , and they may be switched depending on a circuit pattern in the chip 2 . However, when the slit-like beam 3 is emitted from the direction 11 , it becomes necessary to light-shield zero order diffracted light by the spatial filter 202 to eliminate it. At this time, it is also obviously possible to light-shield high-order diffracted light to eliminate it by the spatial filter 202 . As above, the eliminating method of diffracted light has been described in the case of the repeating or nonrepeating pattern present in the chip 2 on the inspected substrate 1 .
[0087] Next, description will be made on detection sensitivity adjustment corresponding to the size of a defect such as a particle to be detected. When a detection pixel size of the one-dimensional sensor (image sensor) 205 such as TDI etc. above the inspected substrate 1 is made small, although the throughput drops, improvement of the detection sensitivity may be expected. Consequently, when a defect such as a particle smaller than about 0.1 μm is to be detected, the detection optical system 200 may be changed to a system in which a pixel size is made smaller. More specifically, three kinds of detection optical system 200 may be provided, in which concerning the pixel size of the image sensor etc., an image size on the wafer 1 is made variable. A realization method of this configuration is that the lens groups 204 are switched. At this time, a configuration of the lenses may be designed so that a light path length from the wafer 1 to the one-dimensional sensor 205 such as TDI etc. needs not to be changed. Also, when such a design is difficult, in addition to switching the lenses, a mechanism for changing a distance to the image sensor may be used. Further, image sensors having different pixel sizes in themselves may be switched.
[0088] It will be apparent to those skilled in the art that although the forgoing description has been made on the embodiments of the invention, the invention is not limited thereto, and various changes and modifications may be made within the spirit of the invention and the scope of the appended claims. | A defect inspecting apparatus of the invention solves a problem that in a defect inspecting apparatus, because of improving detection sensitivity of a microscopic defect by reducing a detection pixel size, a focal depth becomes shallow, a height of imaging is varied due to environmental change and the detection sensitivity of a defect becomes unstable. This apparatus comprises an XY stage, which carries a substrate to be inspected and scans in a predetermined direction, and a mechanism having a system of irradiating a defect on the inspected substrate at a slant and detecting the defect by a detection optical system disposed on the upper side, which corrects a height of imaging in real time for change in temperature and barometric pressure in order to keep the imaging in a best condition. | 6 |
This application is the national phase under 35 U.S.C. § 371 of PCT International Application No. PCT/FR00/02410 which has an International filing date of Aug. 31, 2000, which designated the United States of America.
The present invention relates to an alternating-current motor intended to drive a pump or a compressor.
It is particularly suitable for the production of pumping units which are immersed in a liquid.
It finds its application especially in the oil industry for pumping fluids at the bottom of production wells for hydrocarbons in liquid, gaseous or multi-phase form.
BACKGROUND OF THE INVENTION
The electric motors which are most widely used are single-phase or multi-phase asynchronous alternating-current motors. Their structure is described in TECHNIQUES DE L'INGENIEUR (ENGINEERING TECHNOLOGY), a treatise on electrical engineering, Volume D 3 II Chapter D 3 490 Asynchronous motors—choice and related problems.
According to this document, asynchronous alternating-current motors essentially include a stator and a rotor.
The stator consists of coiled windings of conducting wires distributed within a yoke ring forming a framework and housed within a magnetic circuit supported by this yoke ring. This magnetic circuit is formed by stacks of laminations in the form of circular crowns into which slots are cut parallel to the axis of the yoke ring and in which the conducting wires of the coiled windings are housed.
Within the crown-shaped magnetic circuit formed by the stack of laminations is placed the cylindrical-shaped rotor which includes a rotational shaft supported by a support bearing which is integral with the yoke ring of the stator.
The most widespread type of rotor is the squirrel cage rotor, the circuit of which consists of conducting bars regularly spaced between two metal crown rings forming the extremities.
This squirrel cage is inserted within a magnetic circuit consisting of disks stacked on the rotational shaft.
With this type of motor, since the distances between the windings of the stator are very short, they cannot be supplied with very high voltages and the installation of insulators is an intricate matter.
The same problem is posed for the insulation of the windings with respect to the laminations of the stator circuit.
For certain applications, for example for raising water from a water table or hydrocarbons laid down at the bottom of a well, the shaft of the motor is coupled to a pump and the motor-plus-pump assembly is immersed in the fluid to be pumped.
In this case, the space between the rotor and the stator is filled with liquid, which further accentuates the problems of electrical insulation set out above.
One known solution consists in separating the motor from the pump, but requires the use of a dynamic sealing device mounted on the shaft of the motor. Such sealing devices are delicate and unreliable. They are poorly adapted to the long-term service required for those installations to which access is difficult, expensive or even dangerous.
SUMMARY OF THE INVENTION
The precise object of the present invention is to remedy these drawbacks, and especially to provide an alternating-current electric motor the windings of which can withstand a high voltage and which are easy to produce by virtue of the large distances which separate the windings from each other and the windings from the stator magnetic circuit.
This electric motor is particularly suitable for forming a submerged electric-pump unit.
To this end, the present invention proposes an alternating-current electric motor including a stator magnetic circuit comprising a first part on which electrical windings are mounted and a second, hollow, part within which is mounted a cylindrical rotor equipped with a rotational shaft supported by at least two bearings, which motor is characterized in that it further includes a stator chamber with a leaktight wall, at least a part of which is produced from a non-magnetic insulating material, within which are mounted the first part of the stator magnetic circuit and the electrical windings, the second part of the stator magnetic circuit, the cylindrical rotor and the support bearings lying outside the said chamber and being arranged in such a way that the stator magnetic circuit passes through the wall of the said chamber in the part produced from non-magnetic insulating material.
According to another characteristic of the motor of the invention, with the shaft of the rotor of the said motor being linked mechanically to the shaft of the rotor of a pump, the second part of the stator magnetic circuit, the rotor of the said motor, the support bearings and the rotor of the pump are enclosed in a rotor chamber with a leaktight wall equipped with an inlet and with an outlet for a fluid to be pumped.
According to another characteristic of the motor of the invention, the leaktight wall of the stator chamber includes a device for compensating for the pressure difference between the inside and the outside of the said chamber.
According to another characteristic of the motor of the invention, the stator electrical windings include at least one connection for drawing electrical energy.
According to another characteristic of the motor of the invention, the stator magnetic circuit includes a supplementary electrical winding for drawing electrical energy.
According to another characteristic, the motor of the invention further includes an inlet tapping and an outlet tapping which are mounted on the wall of the stator chamber for connecting an external device for cooling a fluid filling the stator chamber.
According to a final characteristic, the motor of the invention further includes a jacket produced from a non-magnetic insulating material which encases the first part of the stator magnetic circuit, connected in leaktight fashion to the part produced from non-magnetic insulating material of the wall of the chamber in order to render the said chamber leaktight.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics and advantages of the invention will become apparent on reading the description which follows, given by way of example and by reference to the attached drawings, in which:
FIG. 1 is a view in longitudinal section of an electric motor according to a first embodiment of the invention,
FIG. 2 is a side view of a part of an electric motor according to the first embodiment of the invention,
FIG. 3 is a perspective view of a part of an electric motor according to the first embodiment of the invention,
FIG. 4 is a view in longitudinal section of an electric motor according to a second embodiment of the invention,
FIG. 5 is a view in longitudinal section of an electric motor according to a third embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 represents a view in longitudinal section of a first embodiment of the motor 1 of the invention which includes a laminated stator magnetic circuit which comprises:
a first part 2 consisting of three core segments 3 , 4 and 5 , of which only the segments 3 and 4 are visible in FIG. 1, spaced in this instance by 120° and forming a yoke 6 at one of their ends.
a second part 10 , consisting of three core segments 11 , 12 and 13 which extend the three segments 3 , 4 and 5 , of which only 11 and 12 are visible in FIG. 1 and the ends of which form a cylindrical. hollow.
On each of the core segments 3 , 4 and 5 are mounted electrical windings 7 , 8 and 9 of which only 7 and 8 are visible in FIG. 1 .
The three segments 3 , 4 and 5 of the stator magnetic circuit and the electrical windings which they support are placed in a fixed cylindrical casing 19 , closed in leaktight fashion at one end by a back plate 21 and, at the opposite end, by a closure plate 22 .
This plate 22 is produced from an insulating and non-magnetic material so as not to constitute a short-circuit turn around the stator magnetic circuit, nor a magnetic shunt of the same circuit.
The casing 19 and the plate 22 form a leaktight stator chamber 20 . The casing 19 includes a leaktight cable bush for a stator-winding power-supply cable to pass through. The plate 22 includes leaktight bushes 18 for the passage respectively of the three cores of the stator magnetic circuit consisting of the segments 3 , 4 , 5 , 11 , 12 and 13 .
The laminations which constitute the cores of the stator circuit are assembled in leaktight fashion in the region of their passage through the plate 22 , for example by means of a thin layer of flexible insulating material arranged between two adjacent laminations.
The yoke 6 of the stator magnetic circuit 2 is held by the support 26 .
The casing 19 is also equipped with an inlet tapping 23 and with an outlet tapping 24 for connecting an external device for cooling an insulating fluid filling the stator chamber 20 , not represented in FIG. 1 .
In the hollow situated at the end of the second part 10 of the stator magnetic circuit 2 is mounted a laminated rotor 14 which includes a rotational shaft 15 which rests on the fixed bearings 16 and 17 linked mechanically by fixing pieces 41 and 42 to the second part 10 of the stator circuit so as to ensure centering of the rotor and of the stator. The fixing pieces 41 and 42 are produced from insulating and non-magnetic material so as not to form a short-circuit turn around the segments of stator cores and not to magnetically short-circuit the stator magnetic circuit.
FIG. 2 represents a partial side view of the motor, which shows the relative positions of the stator magnetic circuit comprising the core segments 3 , 4 , 5 which are linked by the yoke 6 , the core segments 11 , 12 and 13 , the windings 7 , 8 , 9 mounted on the core segments 3 , 4 , 5 and the rotor 14 with its shaft 15 .
FIG. 3 represents a partial view in perspective of the motor, on which appear the stator magnetic circuit 2 comprising the core segments 3 , 4 , 5 linked by the yoke 6 , the core segments 11 , 12 and 13 , the rotor 14 with its shaft 15 , the electrical winding 7 mounted on the core segment 3 and the plate 22 equipped with a leaktight bush 18 for the passage of the segment 11 .
FIG. 3 further includes a supplementary electrical winding 50 mounted on core segment 3 next to electrical winding 7 . As is known to those skilled in the art, such a supplementary electrical winding forms an electrical transformer together with the stator magnetic circuit and electrical winding 7 . The supplementary winding acts as a secondary winding of the transformer and accordingly is capable of delivering an electrical voltage when winding 7 is supplied with an alternating electrical voltage.
According to a second embodiment represented diagrammatically in longitudinal section in FIG. 4, the motor 1 of the invention has its axis vertical and includes a stator magnetic circuit 2 , electrical windings 7 , 8 , a casing 19 , a plate 22 and a rotor 14 as described for the first embodiment and arranged in the same way.
According to this second embodiment, the motor 1 further includes:
a pump impeller 32 equipped with a shaft 27 linked to the end of the shaft 15 of the rotor 14 and equipped at its lower end with an axial abutment 33 ,
a bellows 40 for compensating for the pressure difference between the two faces of the plate 22 ,
an extension 28 of the casing 19 fitted with an end plate 36 , which forms a rotor chamber 30 which encloses the second part 10 of the stator magnetic circuit, the rotor 14 and the impeller 32 of the pump,
an electrical connection 38 for drawing electrical energy which passes through the casing 21 via a leaktight cable bush 37 .
The shafts 15 and 27 are supported by bearings 16 , 17 and 31 , the bearings 16 and 17 being linked mechanically to the stator magnetic circuit by means of fixing pieces 41 and 42 as in the first embodiment, the bearing 31 and the abutment 33 being integral with the extension 28 of the casing 19 .
The extension 28 of the casing 19 includes an inlet 34 and an outlet 35 for the liquid put into circulation by the impeller 32 driven by the rotor 14 of the motor.
In order to make the motor operate according to this second embodiment, immersed at the very great depth in a liquid, that is to say under very high static pressure, the stator chamber 20 is filled with a liquid.
By virtue of the bellows 40 , the pressures between the stator chamber 20 and the rotor chamber 30 balance out, and thus the problems relating to the pressure difference between these two chambers disappear.
According to a third embodiment represented diagrammatically in longitudinal section in FIG. 5, the motor 1 of the invention has its axis vertical and includes a stator magnetic circuit 2 , electrical windings 7 , 8 , a casing 19 , a plate 22 and a rotor 14 as described for the first embodiment and arranged in the same way.
According to this third embodiment, the leaktight bushes referenced 18 in FIG. 1 are replaced by a jacket referenced 43 in FIG. 5 .
This jacket 43 , produced from an insulating and non-magnetic material, encases the first part 2 of the stator magnetic circuit and is connected in leaktight fashion by a weld 44 to the part 22 of the wall of the stator chamber 20 .
By virtue of this jacket, the leaktightness of the stator chamber 20 is ensured and the stator magnetic circuit is under the pressure conditions of the rotor chamber 13 , which eliminates the problem of leaktightness of the passage through the part 22 of the wall of the rotor chamber 30 by the laminations of the stator magnetic circuit, and especially leaktightness between the laminations which may be difficult to achieve.
By virtue of the shape of the stator windings and of their mounting on the magnetic core segments, their electrical insulation is not limited by the size of the slots as in conventional motors, and, that being so, they can be supplied with voltages substantially higher than those of conventional motors, which avoids the use of a transformer in proximity to the motor when the latter is very far from its electrical power-supply source.
The electric motor of the invention also exhibits the advantage of including only static sealing devices which do not present the drawbacks of dynamic sealing devices, which confers on it great reliability, indispensable for numerous applications in which the motor is difficult of access, for example at the bottom of an offshore oil production well or in a dangerous area, as is the case in the nuclear industry and certain chemical industries where hazardous products are manufactured.
The electrical windings mounted in the leaktight chamber 20 are completely isolated from the surrounding medium and pumped fluid, which renders them insensitive to mechanical and chemical attack relating to the nature of the pumped fluids and of the surrounding medium.
The motor of the invention is particularly suitable for pumping hydrocarbons in multi-phase form at the bottom of offshore production wells at very great depth. | The invention concerns an AC electric motor ( 1 ) comprising a stator magnetic circuit including a first part ( 2 ) whereon are mounted electrical windings ( 7 and 8 ) and a second recessed part ( 10 ) wherein is mounted a rotor ( 14 ). The invention is characterized in that the first part ( 2 ) of the stator magnetic circuit and the electrical windings ( 7 and 8 ) are mounted inside a stator chamber ( 20 ) with sealed wall, the second part ( 10 ) of the stator magnetic circuit, the cylindrical rotor ( 14 ) being located outside said chamber. The invention is applicable in the oil industry for pumping fluids in bottom holes producing hydrocarbons in liquid, gas or polyphase form and in chemical and nuclear industries for pumping dangerous or chemically harmful fluids. | 5 |
RELATED APPLICATION
This application is a continuation-in-part of U.S. application Ser. No. 596,352, filed Apr. 3, 1984 now U.S. Pat. No. 4,535,947.
BACKGROUND OF THE INVENTION
This invention relates generally to a dispensing apparatus for rolled material, and more particularly to a paper towel dispenser and an insert assembly for securing a roll of paper towels to a paper towel holder so as to prevent unintended removal of the paper roll from the holder.
A common problem encountered with the dispensing of rolled articles is the unintended disconnection or removal of scrolled material such as a roll of paper towels, wax paper, or any other similar material from its support. For example, a roll of paper towels is normally supported between a pair of opposing support arms. The support arms are each typically provided with a cylindrical support in the form of a sleeve which is axially inserted within a hollow tubular core member about which the paper towels are scrolled. The cylindrical supports are usually biased inwardly toward the center of the rolled article by the inherent elastic properties of the support arm material. Accordingly, the support arms must be deformed outwardly and spread apart to permit the cylindrical supports to be inserted within the opposite ends of the core of the paper towel scroll.
Once the core has been mounted on a dispenser in the aforedescribed manner, it frequently occurs that the roll becomes dismounted intentionally during use. For example, while a supply of materials being unrolled from the dispenser, the force applied to the cylindrical supports will cause the support arms to deflect outwardly thereby permitting one or both ends of the roll of material to become disconnected from the support arms. Such an occurrence often results in a loss of the scrolled material and, of course, inconveniences the user by having to remount the roll on its support.
While many paper towel holders have been designed, none offers the simplicity and economy of the present invention while at the same time preventing unintended removal of the paper roll from the roll holder. For example, U.S. Pat. No. 2,917,249 to MacLelland discloses a paper roll support having plugs extending into opposing ends of a paper roll for solely supporting the roll thereon. For reloading, either plug must be turned to withdraw it completely outwardly of the roll.
Thus, there exists the need for a simple and economical device for securing and locking a roll of material such as paper towels between a pair of opposed support arms.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to overcome the problems and meet the needs described above by the provision of a device which permits a roll of material to be supported on a roll dispenser in a manner to avoid unintended removal of the roll during dispensing while at the same time permitting reloading of the roll in a simple yet highly effective manner.
The paper roll dispenser according to the invention is structured to prevent a paper roll from sliding off its support arms. A support plug is coaxially disposed within a support cylinder of a paper towel holder such as those currently commercially available. The support plug is inserted within either or both cylindrical support cylinders which are normally provided along the end portions of a pair of support arms. The support plug is adapted for axial displacement within the support cylinder and has a length substantially greater than the length of the cylinder into which it is inserted. Thus, in addition to the support cylinders, the plug or plugs project into the paper roll for further supporting the roll and for preventing unintended removal of the paper roll from the dispenser. Ribs or flanges on the plug, spaced apart a distance greater than the length of the support cylinder, limit movement of the plug in inwardly and outwardly extended positions thereof as these ribs function as limit stops in contact engagement with the support cylinder in such extended positions.
The outer rib on the plug may be designed to frictionally engage the support cylinder for retaining the plug in its inwardly projected position.
Otherwise, the plug may have a retention feature in the form of a detent or a lock bar, located between the spaced ribs, which engages a recess provided in the support cylinder for retaining the plug in its inwardly projected position.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of a typical prior part paper roll dispenser;
FIG. 2 is a front elevational view, partly in section, of the FIG. 1 paper roll dispenser incorporating the support plugs according to the invention;
FIG. 3 is a partial and slightly enlarged view, similar to that of FIG. 2, of the details of a support plug shown in its inwardly projected position during use;
FIG. 4 is a view similar to FIG. 3 showing the support plug positively retained in its inwardly projected position;
FIG. 5 is a view similar to FIG. 3 of another embodiment of the invention;
FIG. 6 is a view similar to FIG. 5 showing the plug in its outwardly extended position;
FIG. 7 is an end view taken substantially along the line 7--7 of FIG. 6;
FIG. 8 is a view similar to FIG. 5 of yet another embodiment according to the invention; and
FIG. 9 is a view taken substantially along the line 9--9 of FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the drawings wherein like reference characters refer to like and corresponding parts throughout the several views, a paper roll dispenser of known construction, generally designated 10 in FIG. 1, has a central body section 11 capable of being secured to a wall or similar support surface in any normal manner. A pair of support arms 12, 13 extend from body section 11 and are typically biased inwardly toward a paper roll 14 shown mounted on the dispenser. Each support arm has an inwardly projecting support cylinder 15, 16 each in the form of a short sleeve usually made integral with the associated wall 17, 18 of the support arms (see FIG. 2).
The paper roll has a tube 19 forming a core about which a roll of paper material of the paper roll is scrolled. The paper roll tube is typically mounted within dispenser 10 by fitting one end of tube 7 over one of the support cylinders 15, 16 and applying an axial force generally along the direction of the paper roll axis so as to deflect the other arm 12, 13 outwardly to allow the opposing end of tube 19 to be fitted over the opposing support cylinder.
Once a paper roll has been mounted in such manner, it is not uncommon for the roll to be unintentionally dismounted or disconnected from dispenser 10. This typically occurs when a user exerts a relatively large force on the paper roll when carrying a quantity of paper therefrom. A component of force is directed along the central axis of the paper roll so as to deflect one or both support arms outwardly thereby resulting in the paper roll tube 19 becoming disconnected from support cylinders 15, 16 such that the paper roll becomes unintentionally separated from the dispenser.
To prevent such unintentional removal of the paper roll from the dispenser, the axial penetration of support cylinders 15, 16 within tube 19 could be increased. However, by increasing such penetration the outward deflection of support arms 12, 13 must be accordingly increased when reloading a paper roll on the dispenser. Since a typical roll dispenser 10 is simply and economically constructed of plastic material, the outward deflection of support arms 12, 13 is effectively limited upon reaching the elastic limit of the material. The same consideration applies for a paper roll dispenser constructed of metal. It has been found that the elastic limit of such plastic or metallic material is reached before an adequate clearance can be provided between opposing support arms 12, 13 to permit paper roll 14 of standard commercially available dimensions to be mounted upon support cylinders 15, 16 having an axial penetration within paper roll tube 19 sufficiently deep to prevent any unintentional removal of the paper roll from the dispenser.
Due to the elastic limits and design considerations noted above, a support plug 21 and/or 22, as shown in FIG. 2, is provided in accordance with the invention to prevent the unintended removal of paper roll 14 from dispenser 10 without requiring undue deflection of support arms 12, 13 beyond their elastic limits. Either a single support plug or a pair of such plugs may be provided with each paper roll dispenser.
One of the support plugs 22 is shown in greater detail in FIGS. 3 and 4 according to one embodiment of the invention. Plug 22 may be in the form of a solid cylinder of plastic material such as polypropylene having a greater stiffness and hardness in comparison with the plastic material from which dispenser 10 is formed, such as high-density polyethylene. The plug has a length substantially greater than the length of support cylinder 16 through which it extends for axial movement between its fully inwardly projected position shown in solid outline in FIG. 3, and its fully outwardly projected position shown in phantom outline in FIG. 3. The plug has a thickened external portion at its inner end which may be in the form of a thin annular rib 23 for limiting axial movement of the plug in its outwardly extended position as rib 23 frictionally engages support cylinder 16 as shown in phantom outline in FIG. 3. And, the plug has a thickened external portion at its outer end which may be in the form of a thin rib 24 for limiting movement of the plug in the inwardly extended position thereof, as shown in FIG. 3. And, with rib 24 being of a harder material compared with support cylinder 16, the plug may be pushed further inwardly to its FIG. 4 position such that the rib 24 frictionally engages support cylinder 16 for retaining the plug in its inwardly projected position. Moreover, the plug may be retained in its outwardly projected position, during reloading, as rib 24 frictionally engages cylinder 16 as shown in phantom outline in FIG. 3.
A grasp bar 25 may be molded onto the outer end wall of the plug to facilitate axial movement of the plug by the user.
Plug 21 may be similarly constructed in a manner described with reference to FIGS. 3 and 4. And, thickened portions may be provided other than in the form of ribs 23 and 24, such as for example discontinuous detents or the like, without departing from the invention.
A support plug 22A is shown in FIGS. 5 to 7 in accordance with another embodiment of the invention. The plug has a rib 23 or the like for limiting plug movement in its outwardly extended position of FIG. 6 similarly as described with reference to FIG. 3. However, the plug has a thickened flange or rib 26, of greater diameter compared to rib 24, at its outer end for limiting the plug in its inwardly extended position of FIG. 5 as flange 26 seats within a recess 27 formed in support arm 13. And, for retaining plug 22A in its inwardly extended position of FIG. 5, a detent in the form of a bead 28 or the like is externally molded on the plug betweem rob 23 and flange 26 for engaging a recess in the form of a transverse groove 29 provided in the inner wall of support cylinder 16 at the inner end thereof, as more clearly shown in FIG. 7.
The inner surface of cylinder 16 is likewise provided with an axial groove 31 which terminates in groove 29 to permit axial movement of plug 22A from its outwardly extending position of FIG. 6 to its inwardly extended position of FIG. 5 as bead 28 slides along groove 31. Thus, during operation, the user simply aligns bead 28 with groove 31, as in FIG. 6, moves the plug to its FIG. 5 position, and thereafter rotates the plug about its central axis so as to move bead 28 into transverse groove 29, as shown in FIG. 7. The plug is thus securely retained in place during towel dispensing.
A further embodiment of the invention is shown in FIGS. 8 and 9 which is essentially the same as one of the embodiments disclosed in parent application Ser. No. 596,352. Here, a support plug in the form of a hollow tube 32 is shown in its inwardly extended and locked position of FIG. 8. A tranversely extending grasp bar 33 is secured to the tube in any normal manner, and a recess 34 is provided in the grasp bar for the reception of an elastic spring element 35. Such element may be in the form of a solid rubber material or foam rubber material secured to the grasp bar within its recess. A base portion 36 of a lock bar 37 is similarly secured to the upper surface of elastic element 35 and is dimensioned to be slidingly received within recess 34. In such manner, the base portion of the lock bar may be depressed within recess 34 by a manual pinching action such that the lock bar is displaced radially inwardly within support tube 32. This inward radial movement of the locking bar causes a locking projection 38 of the lock bar to move beneath the outer surface of support tube 32. It will be seen that such movement will permit the support tube to be axially moved within support cylinder 16 to its inwardly extended position of FIG. 5 and, upon release of the lock bar, be positively retained in place.
Also, support cylinder 16 has an annular groove 39 for receiving locking projection 38, although groove 31 may be omitted since locking projection 38 may be coated with a material having a high coefficient of friction, such as a rubber material, to effect a frictional contact with the inner surface of support cylinder 16.
The inner end of support tube 32 may be provided with a radially outwardly extending shoulder portion 41 having an outer diameter slightly greater than the inner diameter of support cylinder 16. This construction will permit support tube 32 to be inserted within cylinder 16 yet prevent the support tube from being withdrawn therefrom once inserted. And, an outer flange 42 may be provided on the outer end surface of plug 32 to both limit the inward extent of the support plug and to align the lock bar with groove 39 in the event support cylinder 16 is provided with such groove. Thus, with support plug 32 having both a shoulder 41 and flange 42, it will once inserted be permanently secured within cylinder 16 so as to prevent its subsequent misplacement or loss.
In lieu of a spring cushion 35, alternative locking bar biasing means may be provided in the form of coil or leaf springs, or the like, without departing from the invention. And, support plugs 22 and 22A may likewise be in the form of a hollow sleeve, rather than of solid material, within the scope of the invention.
Obviously, many other modifications and variations of the present invention are made possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described. | A dispenser for rolled material has a pair of opposed support arms each provided with a cylindrical support for insertion within a tube about which the rolled material is scrolled. A tubular support assembly is provided for insertion within one or both cylindrical supports for increasing the degree of axial support for more positively supporting and securing the roll on the dispenser. The support plug has limit stops on opposite ends for limiting plug movement in its inwardly and outwardly extended positions, and the plug is capable of being positively retained in its inwardly extended position. | 0 |
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