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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to electric motors and more particularly to the electric motors of an axial gap type which comprises a rotor shaft that is rotatable about its axis, at least one rotor that is fixed to the rotor shaft to rotate therewith and at least one stator that is disposed around the rotor shaft and axially spaced from the rotor.
2. Description of the Related Art
Hitherto, various radial gap electric motors have been proposed and put into practical use particularly in the field of power generators that need higher power density and lower heat generation. Some of them are disclosed in Japanese Laid-open Patent Applications, Tokkaihei 11-341758 and Tokkai 2000-224836.
The motor shown by 11-341758 comprises a cylindrical stator, an outer rotor rotatably disposed around the cylindrical stator and an inner rotor rotatably disposed in the cylindrical stator. While, the motor shown by 2000-224836 comprises a cylindrical stator, an outer rotor rotatably arranged in a diametrically outer side in the cylindrical stator and an inner rotor rotatably arrange in a diametrically inner side in the cylindrical stator.
In both of the motors mentioned hereinabove, by feeding the stator with a compound current, the outer and inner rotors are forced to rotate independently from each other.
In the motor of the latter reference, viz., 2000-224836, it is considerably difficult to provide the inner rotor with a sufficient size due to the inevitably limited space defined in the diametrically inner area of the cylindrical stator, and thus, it is difficult to expect a sufficient torque from such small sized inner rotor. In view of this drawback, electric motors of the type of the former reference, viz., 11-341758 have been widely used in these days.
SUMMARY OF THE INVENTION
Besides the above-mentioned radial gap electric motors, axial gap electric motors are also known, some of which are of a double rotor type having two rotors that are rotatable independently from each other. In this type electric motor, the two rotors are rotatably arranged relative to a fixed single stator. Two output shafts or the like are used for the respective two rotors, that are coaxially installed for receiving the respective torque of the two rotors.
When the axial gap electric motors of the above-mentioned two rotor type are constructed to be powered by a compound current, it is necessary to arrange the two rotors at axially opposed sides of the stator respectively. However, in this case, stable supporting or holding of the stator relative to a motor case is quite difficult because of a complicated arrangement that is inevitably needed by the two rotors, the two output shafts and the single stator on a common axis.
Accordingly, it is an object of the present invention to provide an axial gap electric motor of two rotor type, which is free of the above-mentioned drawbacks.
That is, in accordance with the present invention, there is provided an axial gap electric motor which comprises two stators that are axially arranged and two rotors that are axially arranged between the two stators.
In accordance with a first aspect of the present invention, there is provided an axial gap electric motor which comprises first and second stators that are arranged on mutually spaced positions of an imaginary common axis in a manner to face each other; and a plurality of rotors that are coaxially and rotatably arranged on mutually spaced positions of the imaginary common axis between the first and second stators.
In accordance with a second aspect of the present invention, there is provided an axial gap electric motor which comprises annular first and second stators that are coaxially arranged around an imaginary common axis; annular first and second rotors that are coaxially and rotatably arranged on the imaginary common axis between the first and second stators; a hollow first rotor shaft that is rotatable about the imaginary common axis and has one axial end secured to a center portion of the first rotor to rotate therewith; a second rotor shaft that is rotatably received in the hollow first rotor shaft and has one axial end secured to a center portion of the second rotor to rotate therewith; and a case that houses therein the first and second stators, the first and second rotors, and the first and second rotor shafts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematically illustrated sectional view of an axial gap electric motor of a first embodiment of the present invention;
FIG. 2A is a schematically illustrated plan view of a part of a first rotor employed in the electric motor of the first embodiment of FIG. 1 ;
FIG. 2B is a development provided by developing given portions of the first rotor of FIG. 2A in a circumferential direction;
FIG. 3A is a view similar to FIG. 2A , but showing a part of a second rotor employed in the electric motor of the first embodiment of FIG. 1 ;
FIG. 3B is a development provided by developing given portions of the second rotor of FIG. 3A in a circumferential direction;
FIG. 4A is a view similar to FIG. 2A , but showing a part of a first rotor employed in an axial gap electric motor of a second embodiment of the present invention;
FIG. 4B is a development provided by developing given portions of the first rotor of FIG. 4A in a circumferential direction;
FIG. 5A is a view similar to FIG. 4A , but showing a part of a second rotor employed in the electric motor of the second embodiment of the present invention;
FIG. 5B is a development provided by developing given portions of the second rotor of FIG. 5A in a circumferential direction;
FIG. 6 is a view similar to FIG. 1 , but showing an axial gap electric motor of a third embodiment of the present invention;
FIG. 7A is a schematically illustrated plan view of a part of a first or second rotor employed in the electric motor of the third embodiment;
FIG. 7B is a development provided by developing given portions of the rotor of FIG. 7A in a circumferential direction;
FIG. 8A is a schematically illustrated plan view of a part of another first or second rotor that is employable in the electric motor of the third embodiment; and
FIG. 8B is a development provided by developing given portions of the rotor of FIG. 8A in a circumferential direction.
DETAILED DESCRIPTION OF THE EMBODIMENTS
In the following, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.
For ease of understanding, the following description includes various directional terms, such as, right, left, upper, lower, rightward and the like. However, such terms are to be understood with respect to a drawing or drawings on which a corresponding part or portion is shown. Throughout the specification, substantially the same parts or portions are denoted by the same numerals.
Referring to FIG. 1 , there is shown in a sectioned manner an axial gap electric motor 100 which is a first embodiment of the present invention.
Motor 100 comprises a hollow first rotor shaft 21 and a second rotor shaft 22 that is concentrically and rotatably received in first rotor shaft 21 , as shown.
First and second circular rotors 31 A and 32 A are concentrically connected to right ends of first and second rotor shafts 21 and 22 respectively, so that first rotor 31 A and first rotor shaft 21 rotate like a single unit, and second rotor 32 A and second rotor shaft 22 rotate like another single unit.
An annular first stator 41 and an annular second stator 42 are coaxially arranged around a common axis of first and second rotor shafts 21 and 22 in such a manner as to put therebetween first and second circular rotors 31 A and 32 A. As will be described in detail hereinafter, first and second stators 41 and 42 are secured to axially opposed portions of a motor case 5 respectively.
Motor case 5 comprises generally a circular left wall portion 51 , a circular right wall portion 52 and a cylindrical intermediate wall portion 53 that extends between left and right wall portions 51 and 52 , as shown.
As shown in the drawing, first stator 41 is located at a left position of first circular rotor 31 A to face a left surface of rotor 31 A, and second stator 42 is located at a right position of second circular rotor 32 A to face a right surface of rotor 32 A.
As shown, first rotor shaft 21 is rotatably held by motor case 5 by means of two bearings 61 . While, second rotor shaft 22 is rotatably held by motor case 5 by means of three bearings 62 . Two of bearings 62 are used for a relative rotation between first and second rotor shafts 21 and 22 , as shown.
Each of first and second circular rotors 31 A and 32 A comprises a rotor back core 71 or 72 , a plurality of magnets 81 or 82 , a plurality of rotor cores 91 or 92 and an outer frame 101 or 102 , as will be described in detail hereinafter.
For tight connection between first rotor shaft 21 and first rotor 31 A, screw bolts 121 are used that extend between a raised annular portion 111 formed on first rotor shaft 21 and a base portion of rotor back core 71 . More specifically, after passing through a hole formed in the base portion of rotor back core 71 , each screw bolt 121 is screwed into a threaded bore formed in raised annular portion 111 .
For tight connection between second rotor shaft 22 and second core 32 , screw bolts 122 are used that extend between a raised annular portion 112 formed on the second rotor shaft 22 and a base portion of rotor back core 72 . More specifically, after passing through a hole formed in the base portion of rotor back core 72 , each screw bolt 122 is screwed into a threaded bore formed in raised annular portion 112 .
Each of first and second stators 41 and 42 comprises a stator back core 131 or 132 , a plurality of stator cores 141 or 142 and a plurality of stator coils 151 or 152 .
For tight connection between first stator 41 and motor case 5 , stator back core 131 is secured to the left wall surface of motor case 5 , and for tight connection between second stator 42 and motor case 5 , stator back core 132 is secured to the right wall surface of motor case 5 , as shown.
As shown, around a left end portion of first hollow rotor shaft 21 , there is arranged a first encoder device 161 that senses an angular position of first rotor shaft 21 . Around a right end portion of second rotor shaft 22 , there is arranged a second encoder device 162 that senses an angular position of second rotor shaft 22 .
Motor case 5 is formed with a water jacket 17 in and through which cooling water flows to cool the motor 100 .
Each of stator cores 141 and 142 is a member in and through which magnetic fluxes flow in a direction of the common axis of first and second rotor shafts 21 and 22 . For producing such magnetic fluxes, each stator coil 151 or 152 is put around the corresponding stator core 141 or 142 .
Stator back core 131 or 132 functions to orient the magnetic fluxes of stator cores 141 or 142 around the common axis and force the magnetic fluxes to shift toward another stator core 141 or 142 .
It is to be noted that the number of magnetic poles of magnets 81 that constitute first rotor 31 A differs from the number of magnetic poles of magnets 82 that constitute second rotor 32 . Thus, first rotor 31 A and second rotor 32 A can rotate at different rotation speeds independently when first and second stators 41 and 42 are fed with a compound current, like in the above-mentioned radial gap electric motor.
The detail of the compound current is described in U.S. Pat. No. 6,291,963 granted to Masaki Nakano on Sep. 18, 2001.
When, in operation, first and second stators 41 and 42 are fed with a compound current, first and second rotors 31 A and 32 A are forced to rotate independently. Rotation of first rotor 31 A is transmitted to an external element (not shown) through first rotor shaft 21 , and rotation of second rotor 32 A is transmitted to another external element (not shown) through second rotor shaft 22 .
In the following, the construction of first and second rotors 31 A and 32 A will be described in detail with reference to FIGS. 2A , 2 B, 3 A and 3 B.
Referring to FIGS. 2A and 2B , there is shown in detail first rotor 31 A.
FIG. 2A is a partial plan view of first rotor 31 A, and FIG. 2B is a development provided by developing, in a circumferential direction, portions that show a radius “r 1 ” from a center “C 1 ” of first rotor 31 A.
As is seen from these drawings, first rotor 31 A comprises a rotor back core 71 , a plurality of magnets 81 that are put on opposed surfaces of rotor back core 71 in a manner to have magnetic surfaces in an axial direction, rotor cores 91 each being arranged between adjacent two of magnets 81 while piercing rotor back core 71 , and an outer frame 101 that tightly holds magnets 81 and rotor cores 91 relative to rotor back core 71 .
As shown, magnets 81 are arranged in a manner to alternatively change the N and S poles in a circumferential direction.
Rotor cores 91 are constructed of a magnetic material.
In the illustrated first embodiment, magnets 81 are arranged to constitute six pairs of magnet groups.
Rotor back core 71 and each rotor core 91 are constructed of a plurality of flat magnetic steel sheets that are put on one another. However, if desired, such core 71 and rotor core 91 may be constructed of a pressed powder magnetic material.
As is seen from these drawings, particularly FIG. 2A , flat magnetic steel sheets of rotor core 91 are piled in a radial direction with respect to center “C 1 ” of first rotor 31 A.
Thus, as is understood from the arrows illustrated in FIG. 2B , under operation of motor 100 , there are produced loops of magnetic flux each flowing from a surface of stator 41 into rotor 31 A and flowing through rotor 31 A in an axial direction.
Due to the nature of the magnetic steel sheets piled in the above-mentioned manner, a tendency of shifting flowing of the magnetic flux toward a periphery of rotor 31 A is increased. Accordingly, penetration of the magnetic flux through rotor 31 A (or 32 A) is carried out under the magnetic resistance being reduced in magnitude. Furthermore, due to the same reason, loops of reluctance torque are obtained, which brings about increase in torque of the motor 100 by a degree corresponding to the reluctance torque.
Referring to FIGS. 3A and 3B , there is shown in detail second rotor 32 A.
FIG. 3A is a partial plan view of second rotor 32 A, and FIG. 3B is a development provided by developing, in a circumferential direction, portions that show a radius “r 1 ” from a center “C 2 ” of second rotor 32 A.
As is seen from the drawings, like in the above-mentioned first rotor 31 A, second rotor 32 A comprises rotor back core 72 , a plurality of magnets 82 that are put on opposed surfaces of rotor back core 72 in a manner to have magnetic surfaces in an axial direction, rotor cores 92 each being arranged between adjacent two magnets 82 while piercing rotor back core 72 , and outer frame 102 that tightly holds magnets 82 and rotor cores 92 relative to rotor back core 72 . Rotor cores 92 are constructed of a magnetic material.
In the illustrated first embodiment 100 , magnets 82 are arranged to constitute three pairs of magnet groups.
Other constructional features of this second rotor 32 A are substantially the same as those of the above-mentioned first rotor 31 A, and thus, explanation of such constructional features will be omitted.
As is seen from FIGS. 3A and 3B , particularly FIG. 3A , flat magnetic steel sheets of rotor core 92 are piled in a radial direction with respect to center “C 2 ” of second rotor 32 A. Thus, as is understood from the arrows illustrated in FIG. 3B , there are produced loops of magnetic flux each flowing from a surface of stator 42 into rotor 32 A and flowing through rotor 32 A in an axial direction. Due to nature of the magnetic steel sheets piled in the above-mentioned manner, a tendency of shifting flowing of the magnetic flux toward a periphery of rotor 32 A is increased, like in the above-mentioned first rotor 31 A. Thus, penetration of the magnetic flux through rotor 32 A is carried out under the magnetic resistance being reduced in magnitude. Furthermore, due to the same reason, loops of reluctance torque are obtained, which induces increase in torque of the motor 100 like in case of first rotor 31 .
Referring to FIGS. 4A and 4B , and 5 A and 5 B, there are shown first and second rotors 31 B and 32 B that are employed in a second embodiment 200 of the present invention.
For clarifying a positional relationship between first or second rotor 31 B or 32 B and corresponding first or second stator 41 or 42 , stator cores SC 1 , SC 2 , SC 3 , SC 4 , SC 5 and SC 6 of the stator 41 or 42 are illustrated in FIG. 4A or 5 A by broken lines.
Referring to FIGS. 4A and 4B , there is shown first rotor 31 B.
FIG. 4A is a partial plan view showing first rotor 31 B as viewed behind first stator 41 illustrated by broken lines, and FIG. 4B is a development provided by developing, in a circumferential direction, portions that show a radius “r 1 ” from a center “C 1 ” of first rotor 31 B.
As is seen from these drawings, first rotor 31 B comprises a rotor back core 71 , a plurality of magnets 81 that are put on opposed surfaces of rotor back core 71 in a manner to have magnetic surfaces in an axial direction and an outer frame 101 that tightly holds magnets 81 relative to rotor back core 71 .
Also, in this second embodiment, magnets 81 are arranged to constitute six pairs of magnet groups, like in the case of the first embodiment.
As is understood from the above, in this second embodiment 200 , means that corresponds to rotor cores 91 employed in the above-mentioned first embodiment 100 is not employed. Thus, as is seen from FIG. 4B , loops of reluctance torque are not produced and thus generation of reluctance torque is not expected from first rotor 31 B of this second embodiment 200 .
Referring to FIGS. 5A and 5B , there is shown second rotor 32 B.
FIG. 5A is a partial plan view of second rotor 32 B, and FIG. 5B is a development provided by developing, in a circumferential direction, portions that show a radius “r 1 ” from a center “C 2 ” of second rotor 32 B.
As is seen from the drawings, like in the above-mentioned first rotor 31 B, second rotor 32 B comprises a rotor back core 72 , a plurality of magnets 82 that are put on opposed surfaces of rotor back core 72 in a manner to have magnetic surfaces in an axial direction, and an outer frame 102 that tightly holds magnets 82 relative to rotor back core 72 .
In the illustrated second embodiment 200 , magnets 82 are arranged to constitute three pairs of magnet groups.
Other constructional features of this second rotor 32 B are substantially the same as those of the above-mentioned first rotor 31 B, and thus, explanation of such constructional features will be omitted. Because of lack of means that corresponds to rotor cores 91 , generation of reluctance torque is not expected from second rotor 32 B of this second embodiment 200 .
Referring to FIG. 6 , there is shown in a sectional manner an axial gap electric motor 300 which is a third embodiment of the present invention.
Since motor 300 of this third embodiment is similar in construction to the above-mentioned motor 100 of the first embodiment of FIG. 1 , only first and second rotors 31 C and 32 C that are different from those of the first embodiment 100 will be described in detail in the following.
Referring to FIGS. 7A and 7B , there is shown first rotor 31 C employed in motor 300 of the third embodiment.
As will be described hereinafter, the construction of first rotor 31 C may be used in second rotor 32 C.
FIG. 7A is a partial plan view of first rotor 31 C (or second rotor 32 C), and FIG. 7B is a development provided by developing, in a circumferential direction, portions that show a radius “r 1 ” from a center “C 1 ” of first rotor 31 C (or second rotor 32 C).
As is seen from the drawings, that is, from FIGS. 7A and 7B , first rotor 31 C comprises a rotor back core 71 , a plurality of magnets 81 that are put on one surface of rotor back core 71 in a manner to have magnetic surfaces in an axial direction, rotor cores 91 each being arranged between adjacent two magnets 81 while being embedded at one end in core back core 71 , and an outer frame 101 that tightly holds magnets 81 and rotor cores 91 relative to rotor back core 71 .
Rotor back core 71 and each of rotor cores 91 are constructed of a plurality of flat magnetic steel sheets that are put on one another. However, if desired, such core 71 and rotor core 91 may be constructed of a pressed powder of magnetic material. Furthermore, if desired, rotor cores 91 may be removed like in the above-mentioned second embodiment 200 .
It is to be noted that second rotor 32 C may employ the construction of the above-mentioned first rotor 31 C.
Under operation of motor 300 , there are produced loops of magnetic flux as is shown by arrows in FIG. 7B .
Referring to FIGS. 8A and 8B , there is shown first and second rotors 31 D employable in motor 300 of the third embodiment.
As will be described hereinafter, the construction of first rotor 31 D may be used in second rotor 32 D.
FIG. 8A is a partial plan view of first rotor 31 D (or second rotor 32 D), and FIG. 8B is a development provided by developing, in a circumferential direction, portions that show a radius “r 1 ” from a center “C 1 ” of first rotor 31 D (or second rotor 32 D).
As is seen from these drawings, that is, from FIGS. 8A and 8B , first rotor 31 D comprises a rotor back core 71 , a plurality magnets 81 that are put on one surface of rotor back core 71 in a manner to have magnetic surfaces in an axial direction, and a plurality of rotor cores 91 each being arranged between adjacent two magnets 81 while piercing rotor back bore 71 . It is to be noted that first rotor 31 D has no means corresponding the above-mentioned outer frame 101 ( FIG. 7A ).
As shown in FIGS. 8A and 8B , each rotor core 91 has at a radially outer end thereof an enlarged flange 91 a that is snugly received in a recess formed in an annular supporting member 21 that is attached to the other surface of core back core 71 .
Each rotor core 91 is welded to annular supporting member 21 . Preferably, annular supporting member 21 is constructed of a non-magnetic metal.
As is described hereinabove, the construction of first rotor 31 D may be applied to second rotor 32 D.
Due to provision of annular supporting member 21 , first rotor 31 D or second rotor 32 D has a much increased mechanical strength.
If both first and second rotors 31 D and 32 D have the above-mentioned construction with annular supporting member 21 , the flow of the magnetic flux between the two rotors 31 D and 32 D is much smoothed. If annular supporting member 21 is constructed of a non-magnetic metal, an eddy-current loss caused by permeation of magnetic flux can be reduced.
As will be understood from the foregoing description, in accordance with the present invention, there is provided an axial gap electric motor in which two rotors are independently arranged between two stators.
The number of the magnets held by one rotor may be different from that of the magnets held by the other rotor. With this type arrangement, the two rotors can be independently driven while producing substantially the same torque. Because of the two stators are arranged outside of the two rotors, fixing of the two stators to the motor case is easily made.
In the above-mentioned embodiments 100 , 200 and 300 , two rotors, that is, first and second rotors ( 31 A, 32 A), ( 31 B, 32 B), ( 31 C, 32 C) or ( 31 D, 32 D) are arranged between first and second stators 41 and 42 , more than two rotors may be arranged between the two stators 41 and 42 .
The entire contents of Japanese Patent Application 2004-230725 filed Aug. 6, 2004 are incorporated herein by reference.
Although the invention has been described above with reference to the embodiments of the invention, the invention is not limited to such embodiments as described above. Various modifications and variations of such embodiments may be carried out by those skilled in the art, in light of the above description. | First and second stators are arranged on mutually spaced positions of an imaginary common axis, and first and second rotors are coaxially and rotatably arranged on mutually spaced positions of the imaginary common axis between the first and second stators. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to a method and apparatus for varying the transmission of light through said apparatus, where the transmission is a controllable function of the angle of light incidence.
BACKGROUND OF THE INVENTION
[0002] LCD or liquid crystal displays have found widespread use in modern television and computer screens, wristwatches, calculators and the like. A large proportion of modern LCD displays are based on the twisted nematic liquid crystal due to Helfirch and Schadt (Swiss patent CH532261). The orientation of light entering the device is twisted by liquid crystals which are oriented in a spiral or corkscrew fashion. Due to polarizers at the entrance and exit of the device, only light that is thus twisted will exit the device. Upon application of an electric field normal to the liquid crystal plane ('up' or ‘down’ the stairs), the ability of the liquid crystal to twist light orientation is impaired, blocking light from passing through the device and causing the device to appear darker shades of grey for increasing fields, eventually reaching black for a high enough field. Many such individual devices can be fabricated in close proximity to form an LCD screen. Due to the directional nature of the twisted nematic liquid crystals, light incoming from directions off-normal will be less well modulated by the liquid crystal effect mentioned above. Therefore the viewing angle e.g. of laptop screens is reduced. Great effort has been expended to increase the viewing angle of such devices. However this effect can actually be used to advantage, by effectively blocking the light incident from certain angles and allowing the rest to pass. This use of the directional nature of light absorption by liquid crystals is novel and as will be shown below is of great utility in several applications. In brief, since the disclosed apparatus can block incoming light from a particular direction (such as that of the sun) while passing light from other directions, it is capable of reducing glare and increasing the dynamic range of a scene viewed by a camera, a driver, a pilot, a house occupant, etc. Since the system is electronically controlled, an open- or closed-loop feedback system can modify the direction of greatest light attenuation adaptively to track bright objects and keep them blocked.
[0003] U S patent application 20060209250 discloses a beam steering device using a liquid crystal with an array of back electrodes. Voltages are applied to the array to cause a desired phase distribution across the array, the distribution being selected to steer a beam incident upon the array into a desired direction. Reflective elements are disposed to reflect light incident in the spaces between the electrodes to reduce losses and to smooth the transitions in phase between adjacent electrodes. However the system is not adapted for the selective transmission or absorption of light based on angle of incidence, but rather to steer a beam incident from a known direction in a controlled fashion.
[0004] European patent EP0151703 discloses a directional filter for ambient light constructed from a thin base strip of indeterminate length and having an opaque surface. The strip is wound into a roll having a plurality of convolutions and sections are cut from the face of the roll. A pair of sections are disposed so that their convolutions are in an orthogonal configuration, and are sandwiched between a pair of glass plates having non-reflective outside surfaces. Channels are thereby provided, which impart directional characteristics to the ambient light. However the system is not adapted for the selective transmission or absorption of light based on angle of incidence, but rather to passively impart directional characteristics to the incoming light.
[0005] Similarly European patent EP0658780 discloses a directional filter, characterized by a plurality of lamellae which form mutually parallel beam wells, the interspaces being filled by transparent support bodies whose refractive index causes the incident light to be refracted towards the normal on the plane of incidence. Again the system is not adapted for the selective transmission or absorption of light based on angle of incidence, but rather to passively impart directional characteristics to the incoming light. Patents EP0122830 and U.S. Pat. No. 4,621,898 follow similar lines to EP0658780.
[0006] Hence, a system for a directional filter is still a long felt need.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] In order to understand the invention and to see how it may be implemented in practice, a plurality of embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which
[0008] FIG. 1 schematically presents a standard twisted nematic liquid crystal display (LCD);
[0009] FIGS. 2 a - 2 b schematically illustrate the operation of a standard LCD;
[0010] FIG. 3 schematically illustrates one embodiment of the present invention, with multiple front and back electrodes;
[0011] FIGS. 4 a - c schematically illustrate a sequence of applied voltages and the spatial pattern required to produce a LC orientation parallel to the faces of the LC layer;
[0012] FIG. 4 d . schematically illustrates the applied electric field of FIGS. 4 a - c;
[0013] FIGS. 5 a - 5 c illustrate an example for further manipulations of electric field;
[0014] FIG. 6 illustrates a two dimensional control of the LC directions by using a two-dimensional array of electrodes;
[0015] FIG. 7 illustrates fields with components in the direction parallel to the face of the LC layer are obtained by using resistive, current-carrying electrodes;
[0016] FIG. 8 illustrates another embodiment of the present invention in which directional filter using a PDLC is used;
[0017] FIG. 9 illustrates the transmission of light that is polarized at the xy plane as function of incidence angle in some of the PDLC based embodiments.
[0018] FIG. 10 illustrates an example of a privacy-maintaining window.
SUMMARY OF THE INVENTION
[0019] It is one object of the present invention to provide a multi layer directional filter comprising:
a. a front polarizer; b. a front glass plate provided with a plurality of transparent, individually addressable upper electrodes and addressing lines, said front glass plate being disposed behind said front polarizer; c. a front transparent insulating layer, said front transparent insulating layer being disposed behind said front glass plate; d. a middle liquid crystal layer containing liquid crystal molecules, said liquid crystal molecules having an electric dipole moment, said middle liquid crystal layer being disposed behind said front transparent insulating layer; e. a hind transparent insulating layer, said hind transparent insulating layer being disposed behind said middle liquid crystal layer; f. a hind glass plate provided with a plurality of transparent, individually addressable lower electrodes and addressing lines, said hind glass plate being disposed behind said transparent insulating layer; g. a hind polarizer, said hind polarizer being disposed behind said hind glass plate; and, h. control circuitry adapted to provide sequences of voltage patterns to said electrodes of said front glass plate and said hind glass plate, said control circuitry being adapted to create electric fields at controllable (i) positions, (ii) directions in space; and, (iii) magnitude; wherein said control circuitry is adapted to control the directions of stable equilibrium of said liquid crystals, hence controlling the directions of incidence of maximal light absorption for each pixel individually such that the light coming from said direction of incidence is substantially absorbed whilst light coming from all other directions is substantially transmitted.
[0029] It is another object of the present invention to provide the directional filter as defined above, wherein said front and back insulating layers are additionally provided with a series of grooves in the directions of said front and back polarizers, respectively.
[0030] It is another object of the present invention to provide the directional filter as defined above, wherein said electrodes are composed of indium tin oxide.
[0031] It is another object of the present invention to provide the directional filter as defined above, wherein said transparent insulating layers are comprised of polyimide material.
[0032] It is another object of the present invention to provide the directional filter as defined above, wherein said individually addressable upper and lower electrodes each assume two-dimensional configurations of rows and columns, and wherein said control circuit addresses electrodes belonging to a given row together and applies a single common voltage to all said electrodes of said row in a given phase, and in other temporal phases electrodes belonging to the same column are addressed together and supplied with a common voltage, allowing for two-dimensional control over said direction of incidence of maximal light absorption.
[0033] It is another object of the present invention to provide the directional filter as defined above, wherein the voltages applied to a subset of said individually addressable upper and lower electrodes is of a magnitude less than that required for complete alignment of liquid crystal molecules' orientations parallel to the applied field, thereby further modifying said direction of incidence of maximal light absorption.
[0034] It is another object of the present invention to provide the directional filter as defined above, wherein said electric field, magnitude and direction is independently controlled by said control circuitry.
[0035] It is another object of the present invention to provide the directional filter as defined above, wherein said electric field magnitude and direction is shared by groups of electrodes (pixels).
[0036] It is another object of the present invention to provide the directional filter as defined above, wherein said groups of electrodes are adjacent.
[0037] It is another object of the present invention to provide the directional filter as defined above, said groups of electrodes occupy arbitrary locations.
[0038] It is another object of the present invention to provide the directional filter as defined above, wherein the entire set of said upper electrodes are addressed together, and/or wherein the entire set of said lower electrodes are addressed together.
[0039] It is another object of the present invention to provide the directional filter as defined above, wherein said voltage pattern comprises a set of N distinct voltages applied to subsets of said individually addressable upper and lower electrodes, where N is an integer greater than zero.
[0040] It is another object of the present invention to provide the directional filter as defined above, wherein said voltage pattern additionally comprises a set of M distinct patterns applied over time, where M is an integer greater than zero.
[0041] It is another object of the present invention to provide the directional filter as defined above, wherein said front polarizer is oriented with a polarization direction perpendicular to that of said hind polarizer.
[0042] It is another object of the present invention to provide the directional filter as defined above, wherein said front polarizer is oriented with a polarization direction parallel to that of said hind polarizer.
[0043] It is another object of the present invention to provide the directional filter as defined above, wherein said front polarizer is oriented with a polarization direction aligned in an arbitrary direction with respect to said hind polarizer.
[0044] It is another object of the present invention to provide the directional filter as defined above, wherein said addressing lines on said upper electrodes are oriented perpendicular to the said addressing lines of said lower electrodes.
[0045] It is another object of the present invention to provide the directional filter as defined above, wherein said directional filter is additionally provided with a power source selected from a group consisting of: photovoltaic cells, primary voltaic cells, secondary voltaic cells, and one or more adapters facilitating connection to external power sources.
[0046] It is another object of the present invention to provide the directional filter as defined above, wherein said directional filter is additionally provided with a direction-sensitive light detector in communication with said control circuitry, said control circuitry being adapted to utilize the direction and intensity information obtained from said direction-sensitive light detector to change said direction of incidence of maximal light absorption.
[0047] It is another object of the present invention to provide the directional filter as defined above, wherein said control circuitry is adapted for minimizing flare effect.
[0048] It is another object of the present invention to provide the directional filter as defined above, wherein said control circuitry controls said direction of incidence of maximal light absorption by means of a closed loop algorithm adapted for minimizing error in said direction of incidence of maximal light absorption.
[0049] It is another object of the present invention to provide the directional filter as defined above, wherein the pixels are addressed by a pixel addressing mechanism selected from a group consisting of: passive, active, TFT, or combinations thereof.
[0050] It is another object of the present invention to provide the directional filter as defined above, wherein a first spatial axis of the electric field pattern and subsequent liquid crystal alignment is controlled by applying directional fields using a spatial pattern of voltages in the plane of said first axis, while a second spatial axis the electric field pattern and subsequent liquid crystal alignment is controlled by applying directional fields using a spatial pattern of voltages in the plane of said second axis.
[0051] It is another object of the present invention to provide the directional filter as defined above, wherein one spatial axis of the electric field pattern is controlled by applying a directional field using a spatial pattern of voltages, while the other (orthogonal) spatial axis is controlled by varying the magnitude of applied voltage, thereby achieving two-dimensional control without requiring individual addressing of each pixel in both dimensions.
[0052] It is another object of the present invention to provide the directional filter as defined above, wherein the sequence of voltages applied to said top and bottom electrodes occurs in several temporal phases and in repetitive patterns that induce at the liquid crystal layer electric fields that in a given temporal phase are oriented nearly in the same absolute direction, and wherein the polarity of said electric fields may be reversed without affecting the said absolute direction.
[0053] It is another object of the present invention to provide the directional filter as defined above, wherein two or more of said voltage patterns applied to said top and bottom electrodes induce at the liquid crystal layer electric fields that have nearly the same said absolute direction and induce temporal averages of the local absolute magnitudes of the electric fields along the liquid crystal layer that are relatively uniform.
[0054] It is another object of the present invention to provide the directional filter as defined above, wherein the sequences of voltages applied to the top and bottom electrodes is alternating in several temporal phases so as to induce at the liquid crystal molecules alternating rotational torques in a rate fast enough relative to the rotational response time of the liquid crystal molecules so that the said molecules will assume a desired spatial orientation of their long axes.
[0055] It is another object of the present invention to provide the directional filter as defined above, wherein said voltage patterns applied to the top and bottom electrodes alternate between several phases so as to induce at the liquid crystal molecules alternating rotational torques in a rate fast enough relative to the rotational response time of the liquid crystal molecules so that the spatial orientations of the long axes of said molecules will be stable in time.
[0056] It is another object of the present invention to provide the directional filter as defined above, wherein said voltage patterns applied to said top and bottom electrodes alternate in several temporal phases so as to induce on said liquid crystal molecules alternating rotational torques that orient the long axes of said molecules in a uniform desired spatial direction throughout the volume of the said liquid crystal layer.
[0057] It is another object of the present invention to provide the directional filter as defined above, wherein said directional filter has a shape selected from a group consisting of: planar, simple curve, compound curve.
[0058] It is another object of the present invention to provide the directional filter as defined above, wherein said upper and lower electrodes take the form of parallel, conductive stripes.
[0059] It is another object of the present invention to provide the directional filter as defined above, wherein said sequences of voltage patterns are applied in time periods less than the mechanical rotational time constant of said liquid crystal molecules.
[0060] It is another object of the present invention to provide a multi layer directional filter comprising:
a. a front glass plate provided with a plurality of transparent, individually addressable upper electrodes and addressing lines; b. a front transparent insulating layer, said front transparent insulating layer being disposed behind said front glass plate; c. a middle liquid crystal layer containing droplets of liquid crystal molecules dispersed in a polymer matrix, said middle polymer-dispersed liquid crystal layer being disposed behind said front transparent insulating layer; d. a hind transparent insulating layer, said hind transparent insulating layer being disposed behind said middle polymer-dispersed liquid crystal layer; e. a hind glass plate provided with a plurality of transparent, individually addressable lower electrodes and addressing lines, said hind glass plate being disposed behind said transparent insulating layer; f. control circuitry adapted to provide sequences of voltage patterns to said electrodes of said front glass plate and said hind glass plate, said control circuitry being adapted to create electric fields of controllable (i) positions, (ii) directions in space; and, (iii) magnitudes; wherein said control circuitry is adapted to control the direction of incidence of maximal light scattering for each pixel individually such that the light coming, from said direction of incidence is substantially scattered whilst light coming from all other directions is substantially transmitted.
[0067] It is another object of the present invention to provide the directional filter as defined above, wherein said upper and lower electrodes take the form of parallel, conductive stripes.
[0068] It is another object of the present invention to provide the directional filter as defined above, wherein said sequences of voltage patterns are applied in time periods less than the mechanical rotational time constant of the liquid crystal molecules.
[0069] It is another object of the present invention to provide the directional filter as defined above, wherein said polymer-dispersed liquid crystals' molecules are rotated in time by means of said voltage patterns applied by said control circuitry.
[0070] It is another object of the present invention to provide the directional filter as defined above, wherein said polymer-dispersed liquid crystals molecules' orientations are switched in time by means of said voltage patterns applied by said control circuitry.
[0071] It is another object of the present invention to provide the directional filter as defined above, wherein said polymer-dispersed liquid crystals are stationary and directionally controlled by means of said voltage patterns applied by said control circuitry.
[0072] It is another object of the present invention to provide the directional filter as defined above, additionally supplied with side electrodes in communication with said control circuitry, wherein said side electrodes can create electric fields parallel to the plane of the layers of the device.
[0073] It is another object of the present invention to provide the directional filter as defined above, wherein said transparent upper and lower electrodes are comprised of resistive material, thereby allowing currents to flow through said resistive material over which a voltage drop will occur, creating electric fields with a controllable degree of tilt.
[0074] It is another object of the present invention to provide the directional filter as defined above, wherein said directional filter is additionally provided:
a. zero or more additional glass layers, each said additional glass layer being provided with a plurality of transparent, individually addressable electrodes; b. zero or more additional transparent insulating layers, each said transparent insulating layer being disposed adjacent to said glass layer; c. zero or more additional liquid-crystal containing layers disposed between each of said additional transparent insulating layers; and d. zero or more additional polarizing layers, said additional polarizing layers being disposed in front of or behind said additional glass layers,
wherein said additional glass, transparent insulating, liquid crystal, and polarizing layers serve to increase and/or decrease the range of direction of incidence for which light intensity is attenuated, and can further serve to block more than one direction of incidence simultaneously, or can further serve to nullify redundant attenuated directions.
[0079] It is another object of the present invention to provide the directional filter as defined above, wherein the ratio between the size of said electrodes in their largest dimension to the distance between said upper and lower electrodes is adapted to control the nonlinearities of the electric fields produced by said electrodes.
[0080] It is another object of the present invention to provide the directional filter as defined above, wherein said direction-sensitive light detector is selected from a group consisting of: a four-quadrant light sensor, a light detector array of S sensors where S is an integer greater than 0; a low resolution imaging device; a CMOS imaging device; a CCD imaging device; a set of light sensors; an array of photovoltaic cells; and any device with directional and amplitude sensitivity to incident light.
[0081] It is another object of the present invention to provide the directional filter as defined above, wherein said control circuitry is adapted to track the light sources of greatest intensity and attenuate the light incident from said light sources by means of orienting the liquid crystals of said middle liquid crystal layer in such a direction as to maximally attenuate the light coming from said sources of greatest intensity, if the intensity of said light sources is above a given intensity threshold.
[0082] It is another object of the present invention to provide the directional filter as defined above, adapted to selectively block the light incident upon an optical instrument selected from a group consisting of: camera lens, sunglasses, car windshield visor, motorcycle helmet visor, welding helmet and smart window.
[0083] It is another object of the present invention to provide the directional filter as defined above, adapted to selectively block the light incident upon an optical instrument selected from a group consisting of: camera lens, still camera, video camera, sunglasses, vehicle windshield visor, vehicle visor, motorcyclist helmet visor, welding helmet, window, and smart window.
[0084] It is another object of the present invention to provide an apparatus for increasing optical dynamic range comprising:
a. a front polarizer; b. a front glass plate provided with a plurality of transparent, individually addressable upper electrodes and addressing lines, said front glass plate being disposed behind said front polarizer; c. a front transparent insulating layer, said front transparent insulating layer being disposed behind said front glass plate; d. a middle liquid crystal layer containing liquid crystal molecules, said middle liquid crystal layer being disposed behind said front transparent insulating layer; e. a hind transparent insulating layer, said hind transparent insulating layer being disposed behind said middle liquid crystal layer; f. a hind glass plate provided with a plurality of transparent, individually addressable lower electrodes and addressing lines, hind glass plate being disposed behind said transparent insulating layer; g. a hind polarizer, said hind polarizer being disposed behind said hind glass plate; and, h. control circuitry adapted to provide sequences of voltage patterns to said electrodes of said front glass plate and said hind glass plate, said control circuitry being, adapted to create electric fields at controllable (i) positions, (ii) directions in space; and, (iii) magnitude; wherein said control circuitry is adapted to substantially reduce the transmitted light amplitude coming from the direction of greatest incident radiation, thereby increasing the optical dynamic range of transmitted light.
[0094] It is another object of the present invention to provide the directional filter as defined above, wherein said front and back insulating layers are additionally provided with a series of grooves in the directions of said front and back polarizers, respectively.
[0095] It is another object of the present invention to provide the directional filter as defined above, wherein the refractive index of the PDLC matrix n p is similar to the ordinary refractive index of the liquid crystal material n o , and wherein both said n p and said n o differ from the extraordinary index of the liquid crystal material n e .
[0096] It is another object of the present invention to provide the directional filter as defined above, wherein said voltage sequences are supplied to said upper and lower electrodes so chosen to provide a sequence of electric fields such that the directions of stable equilibrium orientations of said liquid crystal molecules are maintained orthogonal to the direction of required maximal scattering.
[0097] It is another object of the present invention to provide the directional filter as defined above, wherein the orientation of said liquid crystal molecules is rotated in time while maintaining orthogonal orientation relative to the direction of required maximal scattering.
[0098] It is another object of the present invention to provide a privacy-maintaining window for buildings or other applications comprising:
a. a light source disposed outside a window of said building; b. a series of transparent and/or partially mirrored, reflecting surfaces, disposed outside said window of said building;
wherein said series of reflecting surfaces act to reflect the light from said light source towards the outside of said building, while allowing light from outside said building to enter said window, thus allowing occupant(s) of said building to see out of said building while preventing those outside from seeing inside said building.
[0101] It is another object of the present invention to provide a method for directional filtering of light. The method comprising steps selected inter alia from
a. obtaining a front polarizer; b. obtaining a front glass plate having a plurality of transparent, individually addressable upper electrodes and addressing lines; c. disposing said front glass plate behind said front polarizer; d. obtaining a front transparent insulating layer; e. disposing said front transparent insulating layer behind said front glass plate; f. obtaining a middle liquid crystal layer having liquid crystal molecules; g. disposing said middle liquid crystal layer behind said front transparent insulating layer; h. obtaining a hind transparent insulating layer; i. disposing said hind transparent insulating layer behind said middle liquid crystal layer; j. obtaining a hind glass plate provided with a plurality of transparent, individually addressable lower electrodes and addressing lines; k. disposing said hind glass plate behind said transparent insulating layer; l. obtaining a hind polarizer; m. disposing said hind polarizer behind said hind glass plate; and, n. obtaining control circuitry; o. providing sequences of voltage patterns by said control circuitry to said electrodes of said front glass plate and said hind glass plate; thereby creating electric, fields at controllable (i) positions, (ii) directions in space; and, (iii) magnitude;
wherein said control circuitry controls the direction of incidence of maximal light absorption for each pixel individually such that the light coming from said direction of incidence is substantially absorbed whilst light coming from other directions is substantially transmitted.
[0118] It is another object of the present invention to provide the method as defined above, wherein said front and back insulating layers are, additionally provided with a series of grooves in the directions of said front and back polarizers, respectively.
[0119] It is another object of the present invention to provide the method as defined above, wherein said electrodes are composed of indium tin oxide.
[0120] It is another object of the present invention to provide the method as defined above, wherein said transparent insulating layers are comprised of polyimide material.
[0121] It is another object of the present invention to provide the method as defined above, wherein said individually addressable upper and lower electrodes assume a two-dimensional configuration, allowing for two-dimensional control over said direction of incidence of maximal light absorption.
[0122] It is another object of the present invention to provide the method as defined above, wherein said individually addressable upper and lower electrodes are addressed in rows and columns, and wherein electrodes belonging to the same row or column are applied a common voltage, allowing for two-dimensional control over said direction of incidence of maximal light absorption.
[0123] It is another object of the present invention to provide the method as defined above, wherein the voltages applied to a subset of said individually addressable upper and lower electrodes is of a magnitude less than that required for complete alignment of liquid crystal molecules' orientations parallel to the applied field, thereby further modifying said direction of incidence of maximal light absorption.
[0124] It is another object of the present invention to provide the method as defined above, wherein said electric field magnitude and direction is independently controlled by said control circuitry.
[0125] It is another object of the present invention to provide the method as defined above, wherein said electric field magnitude and direction is shared by groups of pixels.
[0126] It is another object of the present invention to provide the method as defined above, wherein said groups of pixels are adjacent.
[0127] It is another object of the present invention to provide the method as defined above, wherein said groups of pixels occupy arbitrary locations.
[0128] It is another object of the present invention to provide the method as defined above, wherein the entire set of said upper electrodes are addressed together, and/or wherein the entire set of said lower electrodes are addressed together.
[0129] It is another object of the present invention to provide the method as defined above, wherein said voltage pattern comprises a set of N distinct voltages applied to subsets of said individually addressable upper and lower electrodes, where N is an integer greater than zero.
[0130] It is another object of the present invention to provide the method as defined above, wherein said voltage pattern additionally comprises a set of M distinct patterns applied over time, where M is an integer greater than zero.
[0131] It is another object of the present invention to provide the method as defined above, wherein said front polarizer is oriented with a polarization direction perpendicular to that of said hind polarizer.
[0132] It is another object of the present invention to provide the method as defined above, wherein said front polarizer is oriented with a polarization direction parallel to that of said hind polarizer.
[0133] It is another object of the present invention to provide the method as defined above, wherein said front polarizer is oriented with a polarization direction aligned in an arbitrary direction with respect to said hind polarizer.
[0134] It is another object of the present invention to provide the method as defined above, wherein said addressing lines on said upper electrodes are oriented perpendicular to the said addressing lines of said lower electrodes.
[0135] It is another object of the present invention to provide the method as defined above, wherein said directional filter is additionally provided with a power source selected from a group consisting of: photovoltaic cells, primary voltaic cells, secondary voltaic cells, and one or more adapters facilitating connection to external power sources.
[0136] It is another object of the present invention to provide the method as defined above, wherein said directional filter is additionally provided with a direction-sensitive light detector in communication with said control circuitry, said control circuitry being adapted to utilize the direction and intensity information obtained from said direction-sensitive light detector to change said direction of incidence of maximal light absorption.
[0137] It is another object of the present invention to provide the method as defined above, wherein the pixels are addressed by a pixel addressing mechanism selected from a group consisting of: passive, active, TFT, or combinations thereof.
[0138] It is another object of the present invention to provide the method as defined above, wherein one axis of the electric field pattern is controlled by applying a directional field using a spatial pattern of voltages, while the other axis is controlled by varying the magnitude of applied voltage, thereby achieving two-dimensional control without requiring individual addressing of each pixel in both dimensions.
[0139] It is another object of the present invention to provide a method for directional filtering of incoming light. The method comprising step selected inter alia from:
a. obtaining a front glass plate provided with a plurality of transparent, individually addressable upper electrodes and addressing lines; b. obtaining a front transparent insulating layer, c. disposing said front transparent insulating layer behind said front glass plate; d. obtaining a middle liquid crystal layer containing droplets of liquid crystal molecules dispersed in a polymer matrix, e. disposing said middle polymer-dispersed liquid crystal layer behind said front transparent insulating layer; f. obtaining a hind transparent insulating layer, g. disposing said hind transparent insulating layer behind said middle liquid crystal layer; h. obtaining a hind glass plate provided with a plurality of transparent, individually addressable lower electrodes and addressing lines, i. disposing said hind glass plate being behind said transparent insulating layer; j. obtaining control circuitry adapted to provide sequences of voltage patterns to said electrodes of said front glass plate and said hind glass plate, said control circuitry being adapted to create electric fields at controllable (i) positions, (ii) directions in space; and, (iii) magnitude; wherein said control circuitry controls the direction of incidence of maximal light scattering for each pixel individually such that the light coming from said direction of incidence is substantially scattered whilst light coming from all other directions is substantially transmitted. It is another object of the present invention to provide the method as defined above, wherein said upper and lower electrodes take the form of parallel, conductive stripes.
[0152] It is another object of the present invention to provide the method as defined above, wherein said individually addressable upper and lower electrodes in some of the temporal phases of addressing the electrodes, electrodes belonging to the same row are fed with the same voltage, and in other temporal phases of addressing the electrodes, electrodes belonging to the same column are fed with the same voltage, allowing for two-dimensional control over said direction of incidence of maximal light absorption.
[0153] It is another object of the present invention to provide the method as defined above, wherein said sequences of voltage patterns are applied in time periods less than the mechanical time constant of the liquid crystal molecules.
[0154] It is another object of the present invention to provide the method as defined above, wherein said polymer-dispersed liquid crystals are rotated in time by means of said voltage patterns applied by said control circuitry.
[0155] It is another object of the present invention to provide the method as defined above, wherein said polymer-dispersed liquid crystals are switched in time by means, of said voltage patterns applied by said control circuitry.
[0156] It is another object of the present invention to provide the method as defined above, wherein said polymer-dispersed liquid crystals are stationary and directionally controlled by means of said voltage patterns applied by said control circuitry.
[0157] It is another object of the present invention to provide the method as defined above, additionally supplied with side electrodes in communication with said control circuitry, wherein said side electrodes can create electric fields parallel to the plane of the layers of the device.
[0158] It is another object of the present invention to provide the method as defined above, wherein said transparent upper and lower electrodes are comprised of resistive material, thereby allowing currents to flow through said resistive material over which a voltage drop will occur, creating electric fields with a controllable degree of tilt.
[0159] It is another object of the present invention to provide the method as defined above, wherein said method comprising of additional steps of providing with zero or more additional glass layers, each said additional glass layer being provided with a plurality of transparent, individually addressable electrodes; zero or more additional transparent insulating layers, each said transparent insulating layer being disposed adjacent to said glass layer; zero or more additional liquid-crystal containing layers disposed between each of said additional transparent insulating layers; and zero or more additional polarizing layers, said additional polarizing layers being disposed in front of or behind said additional glass layers, wherein said additional glass, transparent insulating, liquid crystal, and polarizing layers serve to increase and/or decrease the range of direction of incidence for which light intensity is attenuated, and can further serve to block more than one direction of incidence simultaneously, or serve to nullify redundant attenuated directions.
[0160] It is another object of the present invention to provide the method as defined above, wherein said direction-sensitive light detector is selected from a group consisting of: a four-quadrant light sensor, a light detector array of S sensors where S is an integer greater than 0; a low resolution imaging device; a CMOS imaging device; a CCD imaging device; a set of light sensors; an array of photovoltaic cells; and any device with directional and amplitude sensitivity to incident light.
[0161] It is another object of the present invention to provide the method as defined above, wherein said control circuitry is adapted to track the light sources of greatest intensity and attenuate the light incident from said light sources by means of orienting the liquid crystals of said middle liquid crystal layer in such a direction as to maximally attenuate the light coming from said sources of greatest intensity, if the intensity of said light sources is above a given intensity threshold.
[0162] It is another object of the present invention to provide the method as defined above, adapted to selectively block the light incident upon an optical instrument selected from a group consisting of: camera lens, sunglasses, car windshield visor, motorcycle helmet visor, welding helmet and smart window.
[0163] It is another object of the present invention to provide the method as defined above, adapted to selectively block the light incident upon an optical instrument selected from a group consisting of: camera lens, still camera, video camera, sunglasses, vehicle windshield visor, vehicle visor, motorcyclist helmet visor, welding helmet, window and smart window.
[0164] It is another object of the present invention to provide a method for maintain privacy in buildings comprising:
a. a light source disposed outside a window of said building; b. a series of reflecting surfaces, transparent and/or partially mirrored, disposed outside said window of said building;
wherein said series of reflecting surfaces act to reflect the light from said light source towards the outside of said building, while allowing light from outside said building to enter said window, thus allowing occupant(s) of said building to see out of said building while preventing those outside from seeing inside said building.
[0167] It is another object of the present invention to provide a method for increasing optical dynamic range. The method comprising steps selected inter alia from:
a. providing a front polarizer; b. providing a front glass plate provided with a plurality of transparent, individually addressable upper electrodes and addressing lines, said front glass plate being disposed behind said front polarizer; c. providing a front transparent insulating layer, said front transparent insulating layer being disposed behind said front glass plate; d. providing a middle liquid crystal layer containing liquid crystal molecules, said middle liquid crystal layer being disposed behind said front transparent insulating layer; e. providing a hind transparent insulating layer, said hind transparent insulating layer being disposed behind said middle liquid crystal layer; f. providing a hind glass plate provided with a plurality of transparent, individually addressable lower, electrodes and addressing lines, said hind glass plate being disposed behind said transparent insulating layer; g. providing a hind polarizer, said hind polarizer being disposed behind said hind glass plate; and, h. providing control circuitry adapted to provide sequences of voltage patterns to said electrodes of said front glass plate and said hind glass plate, said control circuitry being adapted to create electric fields at controllable (i) positions, (ii) directions in space; and, (iii) magnitude;
wherein said control circuitry substantially reduces the transmitted light amplitude coming from the direction of greatest incident radiation, thereby increasing the optical dynamic range of transmitted light.
[0176] It is another object of the present invention to provide the method as defined above, wherein said light absorbing pigment(s) are dispersed within the volume of said polymer matrix, and/or are dispersed within any material of said directional filter, and/or are dispersed at any boundary between materials of said directional filter.
[0177] It is still an object of the present invention to provide the method as defined above, wherein a polarizing polymer (or other polarizing material) is included within said polymer matrix, said polarizing polymer being so oriented to absorb light that has an electric field component normal to the plane defined by said polymer dispersed liquid crystal layer.
[0178] It is lastly an object of the present invention to provide the method as defined above, wherein said polymer matrix is made from a polarizing polymer material or other light-polarizing material, and wherein said polarizing material is so oriented as to absorb light that has an electric field component normal to the plane defined by the said polymer dispersed liquid crystal layer.
[0179] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0180] The following description is provided, alongside all chapters of the present invention, so as to enable any person skilled in the art to make use of said invention and sets forth the best modes contemplated by the inventor of carrying out this invention. Various modifications, however, will remain apparent to those skilled in the art, since the generic principles of the present invention have been defined specifically to provide a directional filter.
[0181] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the present invention. However, those skilled in, the art will understand that such embodiments may be practiced without these specific details. Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment or invention. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Lastly, the terms “comprising”, “including”, “having”, and the like, as used in the present application, are intended to be synonymous.
[0182] The term ‘LC’ refers hereinafter to liquid crystal, including birefringent liquid crystals and twisted nematic liquid crystals.
[0183] The term ‘smart window’ refers hereinafter to a window or panel that highly absorbs or highly scatters light incident from a selected spatial direction.
[0184] The term ‘privacy maintaining window’ refers to a window that allows occupants inside a building to see out but prevents people on the outside from seeing in.
[0185] The term ‘LCD’ refers hereinafter to liquid crystal display or to any electro-optic panel based on liquid crystal material.
[0186] The term ‘plurality’ refers hereinafter to any integer number equal or higher 1, e.g, 2-10, especially 2-4.
[0187] The notation ‘n o ’—refers hereinafter to the ordinary refractive index of the liquid crystal.
[0188] The notation ‘n e ’ refers hereinafter to the extraordinary refractive index of the liquid crystal.
[0189] The notation ‘n o ’ refers hereinafter to the refractive index of the polymer that functions as the matrix. For this discussion n p is taken to be equal or similar to n o (n p ≈n o ).
[0190] The term ‘PDLC’ refers hereinafter to Polymer Dispersed Liquid Crystal.
[0191] The term ‘flare effect’ refers hereinafter to non-image forming light that enters an imaging system.
Motivation—Applications
[0192] The present invention discloses a set of apparatii and associated methods to control the direction from which incident light is maximally absorbed by an electrooptic device. We call this device a directional filter. Before going into the technical details of the invention, we first motivate the discussion by describing a series of uses for such a system of control over the direction of maximum absorption. In a camera, for instance, it is often the case that one particular object in the frame (such as the sun) has a much greater brightness than the surroundings. The brightness of this object will ‘steal’ dynamic range from the surroundings causing them to lose contrast they would have in the absence of the bright object. Thus if the bright object could be darkened without darkening the rest of the field of view, full dynamic range would be restored. It will be noticed that a directional filter as described above can achieve just such an effect. If a directional filter as described above is placed over the lens of an ordinary camera, the direction of maximal incident light absorption can be controlled to attenuate the light transmitted from the direction of the sun. Obviously for this implementation it would be advantageous to have a light sensor included in the device, for determining the direction(s) of maximum brightness. Then the direction of maximum attenuation can be dynamically controlled to follow the brightest object(s) in the field of view as it moves.
[0193] Similar applications will be obvious to those skilled in the art. Sunglasses that block the sun but keep the rest of the field of view bright are possible with the directional filter. Vehicle visors that attenuate the sun or the top half of the field of view but keep the rest of the field of view bright are likewise possible. Helmet visors as used in arc-welding are possible which will greatly darken the brightest region where a brilliant arc is present, but leave the rest of the field of view bright and clearly visible (unlike today's helmets, which either blacken most of the scene into obscurity, or else leave a blindingly brilliant region which must be avoided lest one suffer retinal damage). Helmet visors for aircraft or motorcycles can be similarly constructed. Smart windows that attenuate the sun but allow otherwise clear viewing may be constructed for use on houses, or in airplane cabins, or the like. Anti-flare or contrast-enhancing filters can be produced as well. (The ‘flare effect’ in cameras and other imaging system can be avoided. This effect, often appearing as a characteristic polygonal shape with sides dependent on the diaphragm shape, occurs usually near bright objects, when non-image forming light enters the imaging system and is recorded by the image sensor or film. This effect generally lowers overall contrast.)
[0194] All of the above devices may be planar or, curved, or may assume any other shape.
Method of Operation
[0195] Referring to the prior art of FIG. 1 , a twisted nematic LCD comprises six layers. The front polarizer 101 restricts the accepted light to be vertically polarized. Glass layer 102 is provided with transparent electrodes. The polyimide layer 103 underneath it has a ‘brushed’ surface that tends to align the adjacent nematic liquid crystal molecules (which are generally long and thin) of the liquid crystal layer 104 in a particular direction. This direction is chosen to be vertical for the front polyimide layer 103 and horizontal for the back polyimide layer 105 . The crystals in between will try to align themselves to their neighbors resulting in a corkscrew or spiral staircase orientation. The polarization direction of linearly polarized light traveling through such a twisted LC cell follows the rotation of the crystals. Thus in the absence of any further factors (such as an electric field), incoming light will be polarized vertically, travel through the LC cell and thereby become rotated to horizontal polarization, and exit the back polarizer 107 . Schadt and Helfrich discovered an electro-optical effect of a twisted LC layer consisting of positive dielectric nematic molecules under the application of electric fields. They found that the capability of the twisted liquid crystal configuration to rotate the polarization direction of light can be abolished by application of an electric field. Thus the two electrodes 102 , 106 create electric fields in the direction perpendicular to the flat surfaces of the device. These electric fields permeate the nematic liquid crystals in layer 104 . A back polarizer 107 restricts the light passing through this layer to those that are horizontally polarized. The back face 108 may be transparent to allow the light to continue through (in the case of a filter or backlit display) or may be reflective to send the incoming light back to the viewer. Thus in the ‘normal’ state light will pass through the device of FIG. 1 . When an electric field is applied between electrodes 102 , 106 however, light will be blocked causing those, areas under the electrodes of layer 102 to appear dark.
[0196] For a pixel that is under a certain magnitude of electric field there exists an angle of incident light which experiences maximal absorption, such that for light rays entering the device at said angle, the outgoing light rays due to these incoming rays have minimal intensity. This effect is modified by the magnitude of applied voltage. Thus for an LCD device, especially if it is supplied with less than the nominal voltage the pixel has maximal absorption and appears darkest for a certain angle of the incoming light. The applied voltage to the pixel can be utilized to assist in controlling this direction of maximal light attenuation.
[0197] The preferred embodiment of the present invention consists of controlling the direction of maximum absorption by controlling electric field (direction and magnitude) within the liquid crystal material, preferably in two directions (2 degrees of freedom in direction and one in magnitude). The light absorption will be highest at a direction which is a function of the field's direction, of the field's magnitude, and of parameters of the LCD device. This is in contrast to the operation of today's LC-based devices, which rely on fields perpendicular to the device faces, and which cannot selectively control the directions of light absorption and transmission.
[0198] In one embodiment of the invention control over the electric field amplitude and direction is provided independently for each pixel separately. In a second embodiment, control over electric field amplitude and direction is shared by groups of adjacent pixels. In a third embodiment of the invention, control over electric field amplitude and direction is shared by arbitrary groups of pixels. In a fourth embodiment of the invention, control over the electric field amplitude and direction is common to the entire liquid crystal sheet. For all of the above embodiments various spatial locations of the (transparent) electrodes are utilized, and various voltages are applied in a time sequence to said electrodes.
[0199] Referring to the prior art of FIG. 2 a a common implementation of LC control is illustrated. The front polarizer 201 is polarized in the upwards vertical direction as indicated by the arrow 212 . The back polarizer 207 is polarized in the direction coming out of the page, as indicated by arrowhead 213 . Liquid crystals are embedded within the liquid crystal chamber 202 , which is provided with front electrodes 203 , 204 for each pixel, and a back plane electrode 6 , common to all pixels. In the normal ‘off’ state of a twisted nematic LC, no voltage is applied between the electrodes 204 , 206 , and therefore no electric field is present in the LC chamber 202 . If no field was desired, the electrodes could both for instance be grounded as indicated by ground symbols 216 , 208 . In this case the LC molecules take the form of a ‘spiral staircase’, whose form is seen in cross section by the ellipses 214 . The ellipses represent the elongated LC molecules, which are oriented in the vertical direction on the side closest to the front vertical polarizer 212 and are oriented in the direction coming out of the page on the side closest to the back ‘out of page’ polarizer 213 . This alignment of the LC molecules is ensured by a series of grooves at the edges of the LC containing layer 202 . The incoming light beam 208 is rotated by the ‘staircase’ orientations of the LC molecules 214 . Therefore incoming light can exit the back polarizer 207 as a ray 209 that has been reduced by only 50% (due to the front polarizer 201 ).
[0200] When a ‘high enough’ voltage V 0 is applied to one of the front electrodes 203 by means of voltage V 0 217 an electric field results in the horizontal direction, pointing from the front to back electrode. This is the ‘regular’ direction of the electric field used in LCDs and other LC-based devices. As indicated by the ellipses 215 , the LC molecules (which are somewhat elongated structures) are rotated to align in the direction of the field due to torque arising from an internal dipole moment of the LC molecule being twisted by the external electric field. Because of this alignment, the incoming ray 210 is no longer rotated into the ‘out-of-page’ orientation that would enable it to pass through the back polarizer 207 . Instead, the ray is largely absorbed, and the transmitted beam 211 is relatively weak. Thus far, the operation of this apparatus is of the standard type used in most LCDs.
[0201] Next we illustrate the result of using a weakened electric field. A weaker electric field E 1 results from a decreased voltage V 1 that is less than the ‘nominal’ voltage V 0 . The situation is depicted in FIG. 2 b . In this case the LC molecules do not completely rotate into the direction of the field, but rather remain in intermediate orientations as shown by the LC molecules 214 , 215 . The voltages in both top and bottom front electrodes 203 , 204 are kept at V 1 216 , 217 . Now the dependence of transmission amplitude on incidence angle can be shown. For a steep angle of incidence θ 1 in the case of the top ray 208 , the transmission is greatly suppressed, as is shown by outgoing ray 209 . For an incoming ray 210 closer to normal, at angle θ 2 , the transmission is greater as indicated by ray 211 .
[0202] Although in general the front and back polarizers are at right angles, they can in principle be used in a parallel configuration. In that case for zero applied voltage the device will block light, while for a high enough applied voltage the device will largely pass light. For purposes of the present invention, in some embodiments the polarization directions of both polarizers may be parallel, perpendicular, or may have other relative angles.
[0203] Two of the key modifications of the current invention lie in the use of non-facing electrodes and voltage sequences to create fields at arbitrary angles, not just perpendicular to the device faces. As shown in FIG. 3 , in the main embodiment of the device, the single counter electrode of normal LC devices is replaced by a plurality of back electrodes 305 , 306 . A voltage V 0 316 may now (for example) be applied between top front electrode 304 and bottom back electrode 305 , while bottom front electrode 303 and top back electrodes 306 may be left floating 317 , 318 . If the field strength is large enough the LC molecules 314 will again tend to align in the direction of the applied field which now points from top front electrode 304 to bottom back electrode 305 . An incoming ray 308 at an angle θ 1 depending on that of the LC molecules 314 will be maximally attenuated, with small transmission magnitude 309 . An incoming ray at a different angle of incidence θ 2 however will be less attenuated, as seen by transmission magnitude 311 .
[0204] It will now be clear to one skilled in the art that a range of angles may be given to the LC molecules. Referring to FIG. 3 , it will be shown that the LC molecules 314 may be tilted into any angle even though the electrodes 303 - 306 of the example are at fixed positions and hence the angle defined by the lines connecting their midpoints are fixed. One way this may be achieved is by applying a voltage that varies in time. For example, if half the time voltage is applied from bottom front electrode 303 to bottom back electrode 305 (as in FIG. 2 a ), while the other half of the time a voltage is applied between top front electrode 304 and bottom back electrode 305 (as in FIG. 3 ), the direction of the LC molecules will reach an intermediate angle between the horizontal orientation 215 of FIG. 2 a and the large angle of the LC molecules 314 of FIG. 3 . The frequency with which the voltage is alternated may be advantageously chosen to be greater than the relaxation frequency of the LC molecules, such that said molecules do not have time to rotate into the direction of the applied field but are rather trapped in a specific intermediate direction.
[0205] To ensure that the entire LC layer 302 attains the same orientation, two-voltage or multi-voltage temporal sequences may be applied to each of the electrodes that results in a specific spatial pattern. Referring to FIG. 4 a - c , we see the sequence of applied voltages and the spatial pattern required to produce a LC orientation parallel to the faces of the LC layer. A series of individual electrodes is used on both top ( 401 - 405 ) and bottom ( 406 - 410 ) of the LC layer. A voltage pattern is applied that repeats after several electrodes. In the example given, there are transparent electrodes centered every 40 μm, specifically an electrode at θ 1 μm (labeled 401 ), an electrode centered at 40 μm (labeled 402 ), an electrode centered at 80 μm (labeled 403 ), an electrode centered at 120 μm (labeled 404 ), an electrode centered at 160 μm (labeled 405 ), etc. The LC layer 411 (the volume occupied by LC molecules) is in some of the embodiments spaced away from the electrodes by a polyimide layer (labeled 412 ) or by other material. All the specific locations, distances, voltages, electric fields, time interval and/or frequencies are given as examples and do not restrict the generality of the disclosed methods.
[0206] Referring to FIG. 4 a we see the first voltage pattern applied to the electrodes, called ‘phase A’. In phase A the voltage given to the electrode 401 is 0V, the voltage given to electrode 402 is −40V, the voltage given to electrode 403 is 0V, the voltage given to electrode 404 is +40V, and the pattern repeats with the voltage given to electrode 405 of 0V. The same voltages are applied to the bottom electrodes 406 - 410 .
[0207] Referring to FIG. 4 b we see the second voltage pattern applied to the electrodes, called ‘phase B’ which is shifted relative to phase A. In phase B the voltage given to electrode 401 is 40V, the voltage given to electrode 402 is 0V, the voltage given to electrode 403 is −40V, the voltage given to electrode 404 is 0V, and the pattern repeats with the voltage given to electrode 405 of 40V. The same voltages are applied to the bottom electrodes 406 - 410 .
[0208] FIGS. 4 a , 4 b show the electric field vectors 413 (small arrows) and equipotential contours 414 (curved lines) resulting from these voltage patterns. Positive equipotential contours are drawn as solid contours, and negative equipotential contours are drawn as dashed contours. It is evident from these electric field patterns that each LC molecule will experience either a field pointing horizontally (parallel to the plane of the panel), or no field. Furthermore any particular molecule will experience only one direction of field; for instance those centered at 0 μm (between electrodes 401 , 406 ) will experience a right-pointing field in phase A ( FIG. 4 a ) and no field in phase B ( FIG. 4 b ), returning to a right-pointing field in the next phase A. Those molecules centered at 40 μm (between electrodes 402 , 407 ) will experience no field in phase A ( FIG. 4 a ) and a right-pointing field (parallel to the plane of the panel) in phase B ( FIG. 4 b ), returning to no field in the next phase A. Similarly those molecules centered at 80 μm (between electrodes 403 , 407 ) will experience a left-pointing field (also parallel to the plane of the panel) in phase A ( FIG. 4 a ) and no field in phase B ( FIG. 4 b ), returning to a left-pointing field in the next phase A. Those molecules centered at 40 μm (between electrodes 402 , 407 ) will experience no field in phase A ( FIG. 4 a ) and a left-pointing field in phase B ( FIG. 4 b ), returning to no field in the next phase A.
[0209] Also, for most locations within the LC volume, the stronger the electric field in phase A, the weaker it is in phase B, resulting in relatively uniform time-averaged electric fields magnitudes and directions.
[0210] Since applied electric fields exert torques upon the LC molecules unless the molecules are oriented with their long axes parallel to the fields, and since the cycle times for the phase alternations are chosen to be short relative to the LC response time, the LC molecules will reach stable equilibrium orientations that are, for each location, the weighted time-averages of the local applied electric fields.
[0211] It should be noted that due to the symmetry of the LC molecule, reversing the electric field will have no effect on the equilibrium orientation of the molecule. Therefore the two phases A,B referred to above can be followed by further phases C,D of opposite polarity from phases A,B. The average value of the electric field at any point is now zero. A zero net field is known to be advantageous for LC applications since there may be ionic components to the LC suspension or the LC molecules themselves which would tend to drift from their original locations in a nonzero DC field.
[0212] In FIG. 4 c the stable equilibrium orientations of the LC molecules are illustrated by arrows 415 . The arrows' directions are parallel to the stable equilibrium orientations of the long axes, and the arrows' lengths are proportional to the stability of these orientations (the magnitudes of the returning forces). As one can see in the figure, the stable orientations always lie parallel to the panel's plane (in the horizontal plane).
[0213] This sequence of electric field directions is illustrated schematically in FIG. 4 d . In this figure the vertical axis (y-axis) represents the time axis and the x-axis represents the x-direction (horizontal direction) of FIGS. 4 a - c . At 10 ms phase A is applied to the electrodes, causing the LC centered at 0 μm to experience a right-pointing field, those at 40 μm to experience a zero field, those at 80 μm to experience a left-pointing field, etc. At time t=20 ms phase B is applied, with the results pictured. There will be a net average field experienced, and a net average torque tending to align the LC molecules in the direction shown in FIG. 4 c . The opposite voltages are applied in phase C (30 ms) and D (40 ms) with the resulting opposite fields, achieving a zero average field. All references to specific time instances are given as examples and do not restrict the generality of the method.
[0214] Further manipulations are now possible due to the independent control over front and back electrodes. An example is given in FIGS. 5 a - 5 c . Here in phase A ( FIG. 5 a ) one applies voltages −40V, 0V, 40V, 0V, −40V etc to top electrodes 501 - 505 . Bottom electrode voltages however are now shifted with respect to the top electrodes, with voltages 0V, −40V, 0V, 40V, 0V etc applied to bottom electrodes 506 - 510 . Phase B is described in FIG. 5 b . As seen in FIGS. 5 a , 5 b the absolute values of the applied electric fields in the LC volume now have a diagonal direction and their average values over the two temporal phases have a relatively uniform magnitude and direction. The weighted time averages of the applied electric fields result in equilibrium orientations of the LC molecules where zero average torques are exerted on them by the applied fields. These equilibrium orientations are plotted in FIG. 5 c where one sees that the resulting orientations have a 45 degree diagonal direction.
[0215] Intermediate directions can be obtained by use of more than two phases and/or by varying the amounts of time spent in a given phase relative to the other phases and/or by superposition of several sets of voltage sequences each of which results one predetermined equilibrium direction, and/or by pre-defining sets of voltage sequences each of which results a different LC equilibrium direction, and/or by using any method of interpolation or spanning a vector space using a given basis.
[0216] Obviously the ‘standard’ LC direction (normal to the face of the LC layer) can be obtained by applying the same voltage V 1 to all of the top electrodes while, applying a different voltage V 2 to all of the bottom electrodes.
[0217] Two dimensional control of the LC directions can be attained (amongst other methods) by using a two-dimensional array of electrodes. Such an array is illustrated in FIG. 6 , which is a top view of a layer of transparent electrodes for use in a LC control system. In analogy to FIGS. 4 and 5 wherein a linear array of electrodes is used, a planar array of electrodes is used in FIG. 6 . The dark (or grey) features outline the conductive features, and the white areas outline the rest of the panel (non-conductive areas). The relatively large rectangles (or pads of any form) make up the pixels, and the narrow paths make up the electric connections between the pixels. This figure shows only a fraction of the layout. The panel (usually) contains many more pixels, so the actual layout extends beyond this fraction of an area (but continues with the same pattern). The conductive pads and features at the edge (or edges) of the panel for making the external connections are not shown since this is known in the art. By varying the spatial pattern of voltages applied in a timed sequence, at a given temporal phase all pads arranged in a the same row can be held to the same voltage while at another temporal phase all pads arranged in a given column can be held to a given voltage. Therefore, the direction of the LC molecules can now be varied in two dimensions, with full control over the azimuthal and horizon angles of the LC molecules (the long axes of the LC molecules can be oriented toward any desired spatial direction). The traces 601 can be continued through the length of the pattern as it repeats multiple times to cover a large area. By means of the 16 independent traces, full two-dimensional control can be attained, as one-dimensional control was attained in FIGS. 4 and 5 with four independent electrodes. A similar pattern to that shown in FIG. 6 would be printed upon both top and bottom glass or polymer surfaces in order to implement the transparent electrodes. As an example, voltages that may be applied to the pads (electrodes) are written on the corners of each pad. The voltages at temporal phase 1 that define effective row-striped electrodes and thus tilts the LC molecules in the y direction are indicated at the upper-left corner of each pad (Ph 1 ,y). A second phase is required for this tilt and the voltages are indicated at the upper-right corner of each pad (Ph 2 ,y). The two phases that define effective column-striped electrodes and thus tilts the LC molecules in the x direction are indicated at the lower-left and lower-right corners of each pad (Ph 1 ,x and Ph 2 ,x). This example should not decrease the generality of our methods as other voltages, other number of phases, other sequences or other values of any parameter may be used.
[0218] It is within provision of the invention that the transparent electrode layer (such as the layout that is illustrated in FIG. 6 or other layouts that are herein described) may be separated from the liquid crystal layer by a transparent layer, such as a Polyimide layer or any other polymer layer, or any other transparent layer.
[0219] In the example of FIG. 6 the sets of interconnected pixels (pads) located are within a row, or within a column. In this illustration of an example of the layouts of the conductive features, each fourth pixel within a column is interconnected to each other. Therefore, only four edge external connecting pads are required for each column, even if the panel contains hundreds or thousands of pixels in a column. All the pixel's pads that are marked by the same designation (and are located on the same column) are interconnected: all 1A pixels (on the same column) are interconnected, all 2A pixels (on the same column) are interconnected, and so on.
[0220] Obviously a different number of traces could be used to provide finer or coarser control of the electric field direction, or alternatively to control smaller or larger sets of pixels at once, or alternatively to control entire areas of the LCD separately. Also, the interconnecting traces that cross from one side of a column of pixels to the other side of the same column of pixels (see FIG. 6 between row # 4 that contains pads 4 A, 4 B, 4 C etc, and the row above it that contains pads 1 A, 1 B, 1 C etc), may be implemented for each column between different rows, instead of all implemented between the same rows of pixels as appear in FIG. 6 .
[0221] In some embodiments of the invention, all of the pixel's pads that are marked by the same designation (no matter on which column they are located) are interconnected. In other embodiments of the invention, each column has independent four external (edge) connection pads. In some other implementations of this type, each group of more than one adjacent columns has all the pixel's pads that are marked by the same designation (and that are located within one of the columns in that group) are interconnected (and therefore join the same external edge connection pad). In some other implementations of this type, all the pixels that have the same designations from the entire panel are interconnected, but only for a subset of the designation types that are present on the panel. The interconnected pixels join the same external edge connection pad.
[0222] It is emphasized that interconnecting each fourth pixel in a column is only an example. Using the same method, every second pixel in a column or in a row can be interconnected, or every third pixel in a column or in a row can be interconnected, or every fourth pixel in a column, or in a row can be interconnected, or every fifth pixel in a column or in a row can be interconnected, or every sixth pixel in a column or in a row can be interconnected, or every N pixels in a column or in a row can be interconnected, or every other combination of non adjacent pixels in a column, or every other combination of non adjacent pixels in a row, can be interconnected, or every other combination of non adjacent pixels can be interconnected.
[0223] It will be clear to one skilled in the art that many different layouts that are topologically (or conceptually) similar to this layout are possible and these are thus claimed within provision of the invention. Generally speaking, the concept of the present invention consists of an array (or tilted array, or alternating array) of pixels (pads) wherein subsets of such pixels, that are not adjacent to each other, are connected within the panel so that a single (or few) external connecting pad can supply this set of pixels with a required voltage.
[0224] It is emphasized that the interconnections between the columns that are described here are only examples. Every other mean of interconnection between the columns that is based on layouts that are known in the art is also possible, whether it is based on a single layer of conductive material, on two layers of conductive material, or on any number of layers of conductive material.
[0225] Interconnecting similarly-designated columns, using two layers of conductive material (isolated from each other), is also possible.
[0226] The rear glass panel may be constructed similar to the first panel, using similar addressing mode of the pixels, or similar features of conductive material.
[0227] To attain full control over the LC directions, the addressing of the pixels at the bottom panel must be independent from the addressing of the pixels to the top panel, this being required for the generation of tilted electric fields with controllable direction.
[0228] For many of the implementations of panels that are passively addressed (such as the panel described in FIG. 6 , but also for other panels), the features at the opposite panel are placed in 90 degrees rotation relative to the features of the first panel. This will decrease the effect of the ‘dead space’ between electrodes, which will have fields that are generated between the interconnecting paths within the panels.
[0229] For minimizing the volume of the liquid crystal that experiences electric fields that emanate from the narrow conducting traces or paths, the traces on each panel should not lay parallel to the traces on the opposite panel. The features of both panels may, in some of the implementations, be rotated by 90 degrees relative to each other. Thereby much of the influence on the liquid crystal by the narrow conducting traces is eliminated.
[0230] It is within the core of the present invention that any pixel addressing mechanism known in the art, including passive, active, TFT, or any other pixel addressing method be used independently for front and back electrodes of an LC-containing layer. By this independent control of electric potentials for each individual pixel (or local individual pixel) on both sides of the LC layer, the directions and magnitudes of the applied fields for the individual pixels can be controlled, thus the direction of the LC molecules at each individual pixel and/or the whole panel can be controlled, which has the result that the directions and amplitudes of maximum attenuation or attenuations can be controlled individually for each pixel and/or for the entire panel. Another variation of implementing a pixel related 2D directional field control electrodes:
[0231] TFT transistors may be utilized with a sequence of at least 2 temporal phases in a cycle. For the two-phase cycle, in one phase all the pixels that share the same row will be interconnected by the TFT transistors. In the other phase all the pixels that share the same column will be interconnected by the TFT transistors. Thus the electrodes will function like striped-shaped electrodes, but will shift between striped-electrodes in rows and striped-electrodes in columns. In each set of temporal phases electric fields can be generated that can tilt the LC molecules in another plane (there are 2 orthogonal planes that are normal to the LC panel). Therefore the equilibrium orientations of the LC molecules can be controlled as required in all directions.
[0232] In another embodiment of the invention, pixels are grouped into sets, and each set of pixels is controlled independently of the other sets. For instance, relatively distant pixels may be connected. This system results in a reduction of the number of required edge connections to the LC layer from external control circuitry.
[0233] In a preferred embodiment of the invention, both the magnitude of applied voltage and direction thereof are controlled, thereby combining the effects depicted in FIG. 2 b and FIG. 3 . The magnitude of applied voltage changes the direction of maximum absorption. This effect is taken into account and combined with directional control of FIG. 3 , FIG. 4 and FIG. 5 to control both the direction and magnitude of maximal absorption, blocking angle width and/or absorption level at that angle. The control circuit providing the voltages 316 - 319 can thus control not only the darkness of a given pixel but also the direction from which that pixel appears darkest and range of directions affected.
[0234] In another embodiment of the invention, two different methods are used for each axis of a 2-axis control system for the LCD crystals (in e.g. the azimuthal and horizon directions). One axis of control is provided by changing the applied voltage as shown in FIG. 2 b , while the other angle is controlled by the directional field shown in FIG. 3 .
[0235] For additional efficiency, electric fields can be simultaneously established at micro-locations of the liquid crystal that are far enough from each other so as not to distort each other's local electric fields. Since the fields generated by each pad affects only LC molecules that are near this and neighboring pads, the voltage that is applied to a given pad can be applied to other, distant pads without generating electric-field interference. This allows pad addressing embodiments such as described in FIG. 6 , which uses a very small number of addressing lines.
[0236] The applied electric field that is generated by the electrodes is one of the factors that determine the spatial orientation of the LC molecules. The other factors are the directions of the micro-scratches that are implemented on the (Polyimide) transparent boundaries of the LC layer, inter-molecular forces, stray external electric fields, and other secondary effects. The electric field that is generated by the electrodes at each phase polarizes the Liquid Crystal molecules and effects a rotational moment on the molecules that is a function of the local field orientation, local field strength and the orientation of each Liquid Crystal molecule. In each phase (of the period), the voltages that are applied in that phase generate their own electric fields and rotational moments on the Liquid Crystal (LC) molecules. Since the response time of the LC molecules in terms of changing their orientation can be relatively long (and even longer than the time-period of the applied voltages on the electrodes), each LC molecule can integrate or average all the rotational moments that are executed on it during a period (or a cycle).
[0237] A given set of electric fields (one for each phase) that rapidly alternate during each (temporal) period, results in a stable equilibrium orientation for each LC molecule. This means that if the applied voltages on the electrodes were the only factors that generate forces on the LC molecules, and if the temporal period (or cycle) of the alternating phases of these applied voltages were short enough, then each LC molecule averages the rotational moments that affect it in the various phases, and for each LC molecule there is a mechanical equilibrium of its spatial orientation (relative to the electrodes).
[0238] The actual equilibrium spatial orientations of the LC molecules may differ from the equilibrium spatial orientations that are calculated only from the applied voltages on the electrodes, because of the other forces on the LC molecules, but nevertheless the actual equilibrium spatial orientations of the LC molecules are a function of the equilibrium spatial orientations that result only from the effect of the applied voltages on the electrodes.
[0239] If we designate the direction that is normal to the LC layer as the “normal direction” or the “y direction”, and the direction that is parallel to the LC layer as the “lateral direction” or the “x direction”, then in order to generate a homogeneous LC molecules orientation in the normal direction there is no need of two (or multiple) phases, or all the phases can be identical.
[0240] To generate a homogeneous LC molecules orientation in the lateral direction that is maintained in the lateral direction for long distances relative to the electrode widths using relatively low voltages, two or multiple phases of electrode voltage sets are implemented. Each phase creates zones in the LC volume of strong fields and of weak fields, but the phases complement each other so that the resulting equilibrium spatial orientations of the LC molecules due to the effect of the applied voltages on the electrodes is (relatively) homogeneous throughout the LC volume.
[0241] In order to implement any required spatial orientation of the LC molecules (within reasonable limits) at least two methods can be implemented:
a) For any required spatial orientation of the LC molecules, a unique set of voltages is applied to each electrode in each phase of the period (even the number of phases within a period can depend on the said required spatial orientation). b) A discrete set of predefined spatial orientations may be chosen (for example 0°, 45°, 90°, 135° relative to the lateral direction), for which the voltages on all the electrodes in all the phases of the period that are required to produce each orientation in the LC molecules are known (each set of voltages can be applied also after multiplying all the voltages by a factor).
[0244] For any required (arbitrary) spatial orientation of the LC molecules, the two adjoining predefined spatial orientations will be activated alternatively (or simultaneously), with the proper relative weights (by activating each adjoining predefined set for the proper percentage of the time, or by activating each adjoining predefined set with the proper factor to multiply its predefined voltages). For example, if an LC molecules orientation angle of 80° is required, and if the predefined orientations are {0°, 45°, 90°, 135°}, then the two adjoining orientations are 45° and 90°, and either the voltage sets of the 90° are activated for the majority of the time relative to the activation time of the sets of the 45°, or the voltage multiplier of the 90° is larger than the voltage multiplier of the 45°.
[0245] In most of the implementations, a 180° rotational symmetry exists in the LC molecules. Therefore equilibrium spatial orientations that differ by 180° are equivalent (for example 0° and 180° are equivalent; 45° and −135° are equivalent; −45° and 135° are equivalent; 90° and −90° are equivalent; etcetera . . . ).
Resistive Current-Carrying Electrodes
[0246] In another embodiment of the invention, fields with components in the direction parallel to the face of the LC layer are obtained by using resistive, current-carrying electrodes. Since the voltage in such an electrode will drop along its length, the electric fields generated between two such electrodes carefully arranged will have a component in said parallel direction. An example of this embodiment is shown in FIG. 7 . By applying different voltages to the to two ends of a top-side electrode V 1 ,V 2 , and by applying different voltages to the to two ends of a bottom-side electrode V 3 ,V 4 , the electric potentials at each location of each electrode can be controlled, as for each electrode the potential is a linear function or other function determined by the electrode's shape and resistance. The electric field between these electrodes will then take the form indicated by the arrows 703 or other forms that may be tilted relative to the normal to the panel. By varying the voltages involved one may achieve a variety of LC equilibrium angles and hence control the direction of greatest incident light absorption.
[0247] By implementing a pair of electrode layers having parallel stripe-shaped configurations on both sides of the LC layer, and by supplying different voltages to the striped-electrodes, in one or two, or several phases in a period, a controlled tilted electric field is produced within the volume of the LC layer. This field will occur in a plane that is normal to the stripes' direction. By connecting each (or a part of) of the striped-electrode to electrical power sources at each of the ends of the stripe, the current that runs through each striped-electrode can be controlled. Because of the finite electrical resistivity of each striped-electrode (that can also be made relatively high), the current through the stripe creates a gradient of electric potential throughout the stripe, and this produces a gradient of electric potentials also in the (nearby located) volume of the LC layer. Therefore, these currents produce an electric field in the volume of the LC beneath the striped-electrode that is directed parallel to the direction of the stripes, in a two-dimensional analog of the situation shown in FIG. 7 .
[0248] Another embodiment is as follows. Two electrode layers that contain stripe-shaped electrodes at both sides of the LC are used. All the electrodes (in both layers) are parallel to each other. By applying voltages to the electrodes, electric fields can be generated that can have a controllable direction within a plane that is normal to the direction of the stripes. By mechanically rotating the entire LC panel, including all its layers such as the electrode layers, the plane in which the direction of the electric field can span, can be turned, allowing the system to control the direction of the electric field with two degrees of freedom.
[0249] By controlling both the voltages that are supplied to each of the striped-electrodes and the electrical currents that are running through each of the striped-electrodes, electrical fields can be produced in the volume of the LC layer that produce controlled equilibrium directions.
[0250] According to a preferred embodiment of the invention, arrays of transparent electrodes are printed or otherwise deposited on glass panels by methods known in the art. In one embodiment of the invention these electrodes are composed of indium-tin-oxide (ITO). A transparent polyimide layer may be placed or printed between the glass/ITO layer and the LC layer. This polyimide layer is then grooved in a given direction to cause the LC molecules to align in the direction of the grooves. These grooves are often created by rubbing the polyimide layer in the desired groove direction. In some of the embodiments of the invention the grooves at the opposite sides may have a relative angle of 90 degrees; in other embodiments the grooves at the opposite sides may have a relative angle of zero degrees or any other number of degrees. In some of the embodiments of the invention there may be no grooves at a given side or at any side.
[0251] Practical aspects of the implementation of the invention are now discussed. For a finer control over the electric field direction in the LC layer, two methods may be used:
1. Use of smaller electrodes (where ‘small’ is as compared to e.g. the distance between top and bottom electrodes). 2. Use of a large distance from electrodes to LC layer (where ‘large’ is as compared to e.g. the distance between top and bottom electrodes). 3. Use of electrodes on the side of the glass layer opposite the LC layer.
[0255] This large distance may be achieved by use of further glass separation layers or thicker polyimide layers, as will be obvious to one skilled in the art. By way of non-limiting example, consider an LC layer having a thickness of 10 μm (10 micrometer), and transparent electrodes with a width of 30 μm. A reasonable spacing of 30 μm between the electrodes layer and the nearest Polyimide—LC boundary layer (or the nearest LC boundary) is required for achieving reasonable directional control of the electric fields in the LC volume (for the given widths of the electrodes). Such 30 μm spacing may be achieved using a 30 μm thick layer of Polyimide (on each side of the Liquid-Crystal layer). All reference to specific dimensions is only given as an example, and other dimensions may be implemented.
[0256] In one embodiment of the invention the ratio between the size of said electrodes in their largest dimension to the distance between said upper and lower electrodes is between about 10 and 0.01.
[0257] It is within the scope of the invention that any transparent spacer layer material can be used instead of or in addition to a Polyimide layer.
[0258] To block several directions at once, several directional filters as described above may be placed in series, each blocking a particular direction while passing the rest. Alternatively, a single directional filter may be used that simultaneously blocks several directions by dedicating e.g. half of its pixels to blocking a first direction, and using the other half of its pixels to block a second direction. Obviously this method has the drawback that the maximum blocking that can be provided is decreased since the 2 nd direction will be allowed by the 1st pixels and vice versa.
Light Detector
[0259] Most of the aforementioned devices are preferentially equipped with a direction-sensing light detector to allow automatic open- or closed-loop control over the direction of maximum incident light absorption. This may be accomplished by one of many means known in the art such as an array of light sensors, a four-quadrant light detector, a light detector array that has other number of adjacent sensors, a low resolution imaging device (CMOS imaging device or CCD), an imaging device (CMOS imaging device or CCD), a set of light sensors, an array of 2×2 photovoltaic cells, an array of any number of photovoltaic cells, or any other combination of devices that respond to light and that respond differently for light that is coming from different directions. For antiglare applications that protect cameras, surveillance cameras, still cameras, video cameras or similar devices, the imaging device can be the very imaging device of the camera, and/or a separate imaging device. The devices are further preferentially equipped with controlling circuitry of a suitable type that will be obvious to one skilled in the art (such as a microcontroller, an ASIC controller, FPLD, analog circuit, or any other type of controlling circuitry). The devices are preferentially further equipped with a power source (such as photovoltaic cells that may or may not function also as the light detector array, or primary cell(s), or secondary cell(s), or any other type of electric power), or provided with adaptors to facilitate connection to external power sources.
[0260] The direction-sensing light detector determines if a high-intensity light source that radiates light with high enough intensity and with a direction that penetrate the LC panel (and that may reach the protected zone such as the lens or the eyes), is present. The intensity and direction of such glaring light is determined in real-time. Such light may be the sun, or a projector, or headlights, or a welding-arc, or a LASER beam, or any other directional light source.
[0261] Control circuitry with input from the light sensor(s) and output to the directional filter determines the intensity and direction of the required electric field to apply to the liquid crystal material within the panels of the glasses, which will result in light absorption that is maximal in the direction of the high-intensity light source. The amount of said absorption is furthermore controlled such that the rays that arrive from the high-intensity light source and penetrate the directional filter are attenuated enough to prevent glare in the transmitted light (which eventually is used by e.g. a camera or a user). In many of the implementations, the operator, the system or the user has control over the magnitude of the maximal attenuation (in several of the implementations the operator, the system or the user may also have control over the direction of maximum absorption).
[0262] The preferred location and orientation of the light detector array should be such that it will face approximately in the direction of expected incoming light. For example this would be toward the same direction as the lens faces for camera protection applications, toward the front of the sunglasses (normal to the lenses) for sunglasses applications, or in general oriented such that the center of the filter's light sensing field of view will be similar to the center of the light sensing field of view of the protected camera, system or user. The light detector array can be located at any location that has field of view to the front of the camera, system or sunglasses, or can be the camera's own light detector array. There may be more than one light detector array. The determination of the direction and intensity of the high-intensity light source can be performed in several ways:
1) Imaging device with lens (or lenses, or a mirror, or mirrors, or with a pinhole). The imaging device can be implemented using CCD, CMOS imaging technology, photovoltaic array, or any other imaging technology known in the art. From the location of the focused image of the light source on the surface of the imaging device or the light detector array, the direction of the direct glaring light rays can be inferred. 2) Four-quadrant light detector (or a detector with any other number of light sensing regions), or an imaging device, or photovoltaic array, with a focusing device such as a lens (or lenses, or mirror, or mirrors) that is placed such that light that arrives from sufficiently large field of view at the front of the sunglasses will be converged but not necessarily focused at the light detector's plane. 3) Four-quadrant light detector (or any other number of light sensing regions), or an imaging device, or photovoltaic array, with a hole (or transparent opening) in front of the light detector array.
Directional Filter Utilizing Polymer Dispersed Liquid Crystal
[0266] Another embodiment of the directional filter involves panels where micro droplets of liquid crystal material(s) are dispersed within a polymer matrix also known as a Polymer Dispersed Liquid Crystal. Our novel approach involves using multiple electrodes at each face of the PDLC sheet (at each side of the plane that is defined by the PDLC), so that by supplying each electrode with voltages that change in time, electric fields are produced in the volume of the PDLC sheet, possibly in several temporal phases. The spatial orientations and magnitudes of the electric fields in each temporal phase are controlled by said applied voltages (which are used to control the orientation of the long axes of the LC molecules, by methods similar to those explained in the previous embodiments not using PDLC).
[0267] In each temporal phase the produced electric fields exert forces on the liquid crystal molecules that are in effect mechanical moments that tend to reorient the LC (liquid crystal) molecules along the local lines of electric field. By switching at a fast enough rate between several applied electric fields (with each field exerting a different set of moments on the LC molecules), each LC molecule will assume a spatial orientation in which the mean mechanical moment on itself will nullify. Each LC molecule will be in an equilibrium orientation (that can be described by two orthogonal angles).
[0268] All the concepts, methods and implementations that are discussed in this document regarding the generation of electric fields with controlled orientations (and magnitudes) within the volume of a regular liquid crystal sheet, apply also to the generation of electric fields with controlled orientations (and magnitudes) within the volume of a PDLC (Polymer Dispersed Liquid Crystal) sheet, and apply also to the generation of electric fields with controlled orientations (and magnitudes) within the volume of a PSLC (Polymer Stabilized Liquid Crystal) sheet.
[0269] The device has a set of transparent electrodes at each side of the PDLC panel that are addressed by various voltages that switch in time, all as described in this document so as to generate controllable electric fields within the volume of the PDLC panel (or sheet) that exert electrical forces on the liquid crystal molecules within the panel that let the orientation of the liquid crystal molecules be stable at a controllable direction (a direction that is defined by two independent spatial angles).
[0270] A directional filter using this embodiment, preferentially uses a refractive index of the (usually polymer) matrix n p similar to the ordinary refractive index of the LC material n o , both being different from the LC's extraordinary refractive index n e . When the long axes of the bulk or of all of its LC molecules are oriented toward a specific spatial direction (the “LC direction”), the difference between the refraction indices n p and n e , combined with the highly curved shapes of the LC droplets, will scatter light rays whose direction of incidence is approximately normal to the LC orientation and are polarized parallel to the LC direction. The result is a panel that is relatively transparent in most directions but has relatively hazy, or blurred stripe in the directions normal to the LC direction. We shall define the spatial direction from which direct glaring rays appear, or the spatial direction at which the view needs to be blocked, as the “particular direction”.
[0271] In one embodiment of the invention, a PDLC sheet as described in this document and/or as known in the art is provided with sets of transparent electrodes that function as described above. Said electrodes enable the production of electrical fields within the volume of the PDLC sheet with arbitrary controlled spatial orientations and further enable production of the required equilibrium orientations of the liquid crystal molecules within the liquid crystal droplets.
[0272] The applied voltages orient the liquid crystal molecules within the liquid crystal droplets; the orientation of the long axes of the LC molecules (the “LC direction”) always maintains 90 degrees angle relative to the “particular direction”. In several implementations the applied electric fields within the volume of the PDLC film are rotated in time so that the LC molecules' orientation also rotates. Each molecule rotates around an axis that passes through the molecule and is oriented parallel to said “particular direction”.
[0273] In FIG. 8 an embodiment of the directional filter using a PDLC is illustrated. Transparent electrodes 801 , 802 are used to induce electric fields in the LC layer as in the aforementioned LC embodiments.
[0274] See FIG. 9 for an illustration of an example of the normalized light transmission graph, showing transmission 904 as a function of the spatial direction of the incoming light. The graph illustrates the transmission for light rays which are polarized with electrical components that are in planes that contain lines that are parallel to the “LC direction”. In other words, the graph illustrates the transmission for light rays which are not polarized normal to the orientation of the long axes of the LC molecules 903 . The orientation of the long axes of the LC molecules 903 , the “LC direction”, is always maintained normal to the “particular direction” 905 , while said “LC direction” is also rotated in time around an axis parallel to the “particular direction”. Therefore, the panel will appear to a viewer that observes or to a camera that images a scene through the panel as hazy for a rotating stripe that rotates 902 around an axis 905 that connects the viewer with the object at the far side of the “particular direction”, and as progressively more transparent for view angles that are further from the hazy stripe.
[0275] Since the said hazy stripe rotates quickly in time (in comparison to the speed of the human visual system), only the “particular direction” will always be obstructed by haziness, but the other directions will be obstructed for only part of the time of the cycle of rotation, and therefore the view to the observer will be clearer and more transparent as the viewing angle is further away from the “particular direction”.
[0276] Generally one will employ two mutually orthogonal rotating (or not rotating, or switching) “hazy stripes”.
[0277] By implementing two cascading layers (one on top of the other) of PDLC with independent sets of controlling electrodes, so that the incoming light will have to pass both layers in order to pass the whole panel, and by feeding controlling voltages that generate the said hazy stripe in both PDLC layers where the two hazy stripes are mutually orthogonal (and both still rotating in time), all light arriving from the “particular direction” will be scattered (and virtually no light arriving from the “particular direction” will pass the device directly). The view to the observer will be clearer and more transparent as the viewing angle is further away from the “particular direction”.
[0278] In this set of implementations, the orientations of both “LC directions” (which are the orientations of the long axes of the LC molecules at the PDLC layer that is far from the viewer and the PDLC layers that is near the viewer), are orthogonal to the “particular direction”. Also, the orientation of the “LC direction” at the PDLC layer that is far from the viewer is orthogonal to the “LC direction” of the PDLC layer that is near the viewer.
[0279] In some embodiments of the invention the orientation of the LC molecules is rotated in time. In some implementations the orientation of the LC molecules is not rotated in time. In some implementations of the invention the orientation of the LC molecules is switched in time.
[0280] By generating electric fields at the side of the PDLC panel further from the viewer that establish equilibrium orientations of the LC molecules at the further side from the viewer that are orthogonal (normal) to the “particular direction” 905 , and at the same time generating electric fields at the side of the PDLC panel near to viewer that establish equilibrium orientations of the LC molecules at the near side relative to the viewer that are orthogonal (normal) to the “particular direction” but that are also orthogonal (normal) to the orientation of the LC molecules at the further side from the viewer, the view seen by the viewer will be of two orthogonal hazy stripes that cross each other at the “particular direction”. Virtually no light that arrives from the “particular direction”, of any polarity, will pass directly towards the viewer (nor pass in the opposite direction).
[0281] The generation of the required fields only at a particular side of the panel is performed using only (or using primarily) the electrodes at the same side. At the same time, the electrodes at the opposite side are used to generate orthogonal fields.
[0282] In some embodiments of the invention, the orientations of the LC molecules are also a function of the depth within the PDLC panel.
[0283] In some embodiments the invention a light absorbing pigment is dispersed within the volume of the PDLC panel, preferably within the volume of the polymer matrix. This pigment may also be dispersed within any material of the device or at any boundary between materials within the PDLC panel.
[0284] In some of the embodiments of this device a polarizer polymer (or other polarizer material) is included within the PDLC panel so that the polarizer absorbs, within the volume of the PDLC panel, light that has an electric field component that is oriented normal to the plane that is defined by the PDLC panel. Only light that travels in a direction tangent (or parallel) to the plane that is defined by the PDLC panel may have this electric field component, although light that travels in a direction tangent to the plane of the PDLC panel may also have an electric field that is oriented tangent to the plane of the PDLC panel. Therefore including such polarizer material within the volume of the PDLC panel will result the absorption one of the two components of the light that travels parallel to the PDLC plane (within the volume of the PDLC panel) but will not affect light that travels normal to the PDLC plane.
[0285] Any discussion, description, or drawing in this document regarding controlling the orientations of liquid crystal molecules using electric fields may also find application in implementations that incorporate liquid crystal droplets embedded within a transparent polymer matrix.
[0286] Any discussion, description, or drawing in this document regarding a single panel utilizing liquid crystal material(s), with or without it's controlling electrodes, with or without a single or dual polarizers at its faces, with a continuous (regular) or polymer dispersed LC construction, should be regarded also as dual or multi panel construction, in which light rays pass both or all of the panels in series. The LC panels for the dual or multi-panel constructions may be parallel or tilted relative to each other.
Privacy Maintaining Windows
[0287] Reference is now made to FIG. 10 which illustrates another embodiment of the present invention. In this embodiment of the invention a window is illustrated that allows an occupant of a room to observe the outside scene while blocking the inside scene from the outside world. This is in principle a form of one-way window. The operation is based upon reflection of incoming light from the transparent or partially mirrored surfaces shown in the figure.
[0288] The principle is to use reflection of light from transparent or slightly mirrored glass or plastic sheet or sheets 1004 , 1005 . The light source(s) 1001 , 1002 is placed outside the window in places that interfere little with the view through the window.
[0289] After being reflected and/or diffused by the fixture 1006 , and/or diffused by sheet 1003 , the light then reaches a clear or partially mirrored sheet or sheets of transparent glass or plastic 1004 , 1005 that are located outside the window (the “reflective sheets”). These are advantageously supplied with couplings 1008 for attachment to the wall 1007 . Some of the light is reflected from the surface (or surfaces) of these sheets in directions away from the house (and away from the window's frame).
[0290] The brightness of the reflected light from the “reflective” sheets is much higher than the brightness level of the view of the room from outside the house. This is achieved by using a high enough level of illumination of the external light source and by having enough mirror coating at the reflective sheets.
[0291] The reflective sheets produce glare that interferes with the view through the window 1009 , when observing the inside of the room from the outside. However an occupant of the room will be able to see outside easily. This is due to the fact that the light rays that originate from the external light source and that are reflected by the “reflective” sheets, advance only (or mostly) away from the house. The person(s) inside the house can watch the view through the window without being subjected to this glare.
[0292] The aforementioned lamp (the “external lamp”) contains some light diffusing element (diffused reflectors, and/or translucent—matt glass or plastic panel, and/or diffused primary light source such as an array of fluorescent tubes). The said external light therefore reaches the “reflective sheets” from many directions and thus reflects towards many external directions. | The present invention provides a multi layer directional filter comprising (a) a front polarizer, (b) a front glass plate provided with a plurality of transparent, individually addressable upper electrodes and addressing lines, said front glass plate being disposed behind said front polarizer, (c) a front transparent insulating layer, said front transparent insulating layer being disposed behind said front glass plate, (d) a middle liquid crystal layer containing liquid crystal molecules, (e) a hind transparent insulating layer, said hind transparent insulating layer being disposed behind said middle liquid crystal layer, (f) a hind glass plate provided with a plurality of transparent, individually addressable lower electrodes and addressing lines, (g) a hind polarizer, said hind polarizer being disposed behind said hind glass plate, and, (h) control circuitry adapted to provide sequences of voltage patterns to said electrodes of said front glass plate and said hind glass plate. | 4 |
PRIORITY CLAIM
[0001] This application claims the benefit of U.S. Provisional Application No. 60/236,211 filed Sep. 28, 2000 entitled “Flexible Sign Illumination Apparatus, System and Method.”
FIELD OF THE INVENTION
[0002] This invention relates generally to illuminating light strips and, more particularly, to flexible LED light strips that are readily customized to fit signs and other lighted installations, and a system and a method for doing the same.
BACKGROUND
[0003] Illuminated installations of various different shape, color and size are used to communicate with people. Their uses have an extremely wide range, from warning signs for motorists, to illuminated building facia, to a company's name on a skyscraper. The wide-spread use of these illuminations can be partially attributed to their visibility; in all weathers, day or night, illuminated signs, designs and indicia can be seen easily.
[0004] However, the advantages of illuminated signs and other installations come at a significant cost. To illuminate a sign from within, a transparent casing in the shape of the desired sign must be manufactured. Generally, incandescent or neon lights are permanently affixed inside the sign casing. In some cases, the light network must be customized to fit the unique dimensions of the sign. Therefore, installation of the lights into the signs can be time consuming and expensive.
[0005] Maintaining the signs is also costly. If one light burns out, an entire portion of the sign loses illumination. This is commonly seen when one or more letters of a sign are not visible at night due to a burnt out light. Furthermore, power consumption by incandescent and neon lighting is very high. This, in conjunction with the wide-spread use of these signs leads to mass consumption of electricity, placing a significant burden on the power plants and further polluting the environment. In sum, the installation of lights to fit the signs and maintenance of the sign are costly at many levels.
SUMMARY OF THE INVENTION
[0006] The preferred embodiments of the present invention provide energy-efficient and reliable light strip illumination apparatus that can easily be customized and installed for both new installations and retrofitting incandescent and neon installations. One preferred embodiment includes a narrow strip flexible printed circuit board, energy efficient LED lights, a Velcro fastener, and power connectors. The LEDs are mounted onto one side of the circuit board and the fastener is attached to the opposite side of the circuit board. The power connectors couple multiple circuit boards to form a continuous network of lights.
[0007] The strip of flexible printed circuit board provides a platform for positioning the LEDs along the strip. The flexibility of the circuit board allows the light strip to be readily shaped to conform to the housing of the light fixture thereby enabling easy, inexpensive, and quick customization of lights to illuminate a sign or other installation.
[0008] In the preferred embodiments of the invention, the energy efficient LED lights are positioned in an array and the lights are electrically coupled in series within the array. A plurality of arrays are grouped to form a section and the arrays within the section are electrically coupled in parallel. Multiple sections are electrically coupled in parallel positioned along the circuit board. A feature of this construction is the partial burnout of an array of lights isolates light failure to that array only, which allows the rest of the lights to continue to provide illumination.
[0009] In one embodiment of the illumination system, multiple light strips are attached to a transparent sign casing where the receiving portions of Velcro fastener are attached to the designated areas. These strips are electrically coupled by power connectors. A “step down” transformer converts the line voltage from an electrical outlet into 24 volt AC current and supplies it to the LEDs through the power connector.
[0010] A feature of one of the preferred embodiments is that the printed circuits are laid out so that one or more sections of the flexible strip can be cut to customize the light strips to fit signs or other lighted features of any size or shape. Advantageously, marks are placed between the sections where the light strips can be cut.
[0011] In one preferred embodiment of a method of customizing and installing the light strips, the receiving portions of Velcro fastener are attached to the inside of the transparent sign casing. Equivalent lengths of the flexible light strip are bent to fit the shapes of the sign, measured, cut, and fastened onto the receiving portions of the Velcro fastener. The power connectors are used to electrically couple the strips and negotiate sharp angles for a better fit.
[0012] The use of Velcro fasteners attached to the strips allows easy attachment of the strips to the sign. The strips can be cut on-site to fit the dimensions of the sign. Using energy efficient lights such LEDs can reduce power consumption by six to ten times that of incandescent or gas tube lights in similar applications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:
[0014] [0014]FIG. 1 shows a plurality of light strips connected by a power connector and powered by a common household AC source using a step down transformer;
[0015] [0015]FIG. 2 a shows sections of the light strip assembly powered by a battery;
[0016] [0016]FIG. 2 b shows the bottom of the light strip, one showing the bare circuit board and the other showing the circuit board with Velcro fastener attached;
[0017] [0017]FIG. 3 a shows a circuit diagram for one embodiment of the light strip powered by a battery;
[0018] [0018]FIG. 3 b shows a circuit diagram for one embodiment of the light strip powered by AC input;
[0019] [0019]FIG. 4 a shows coupling of multiple light strips by a power connector;
[0020] [0020]FIG. 4 b shows the placement of power connectors on the light strip;
[0021] [0021]FIG. 5 shows one embodiment of the light strip using a Velcro fastener;
[0022] [0022]FIG. 6 shows flexibility of the sign illumination apparatus by bending to fit the inside of a letter “C”; and
[0023] [0023]FIG. 7 shows custom-fitting of the sign illumination apparatus in a letter “T,” where the power connectors are used to negotiate a sharp angle.
DESCRIPTION
[0024] As shown in FIG. 1, an exemplary apparatus for sign illumination 1 comprises a flexible strip of printed circuit board 2 , energy efficient lights 3 , a fastener 19 / 20 , (shown in detail in FIG. 5) and a power connector 11 . The energy efficient LED lights 3 are mounted on the top of the circuit board strip 2 and the fastener 19 is attached to the bottom of the circuit board. The power connector 11 is coupled to the lights 3 as a conduit for electricity. In exemplary light strip systems, one or more of the strips 1 are electrically coupled end-to-end to each other by the power connectors 11 .
[0025] Many types of flexible material may be used as a platform for the lights 3 . A preferred choice is the Type FR4 inner core material that is approximately ten to twenty thousandth thickness. This type of material is readily available through vendors. In one embodiment, the circuit board 2 is in the shape of a strip that is flexible enough to bend to form a circle of approximately 2 inches in diameter. However, one skilled in the art will recognize that other suitable material with varying levels of flexibility can be cut in shapes other than a strip to provide a platform for the lights 3 . For example, thinner sheets of laminated circuit boards may be used. The material does not have to be a circuit board material as long as it is flexible and allows electrical coupling of the lights 3 .
[0026] The energy efficient lights 3 are positioned in sections 8 of arrays 5 . As shown in FIGS. 2 a and 2 b , twelve lights are grouped in arrays 5 and two arrays 5 are positioned next to each other to form a section 8 . One or more sections 8 are placed along the circuit board 2 , with severance areas 7 located between the sections 8 . Resistors 6 are positioned out of the way of the lights 3 . At least one set of terminals 4 are located on each section 8 for coupling with the power connector 11 . One portion of a fastener 19 is attached to the bottom of the circuit board 2 .
[0027] It will be obvious to one skilled in the art that the particular arrangement of the lights 3 and the location of the terminal 4 can be varied to suit the relevant application. For example, more than two arrays 5 can be positioned next to each other to form a wider section 8 . The lights 3 can also be positioned in clusters with severance areas between the clusters and the terminals on the side of the strip rather than at the ends.
[0028] [0028]FIGS. 3 a and 3 b shows an exemplary circuit diagram of the light 3 . The power source can be either DC current 17 or AC current 13 . One or more resistors 6 can be used depending on the type of LED 3 used to moderate the electrical current and to protect against accidental electrical overload in cases where the rate of current is not constant. Resistors 6 may not be necessary if the rate of current is relatively constant. The lights 3 within the array 5 are connected in series. The arrays 5 are coupled to each other in parallel. The sections 8 are also connected in parallel. The severance area 7 can be any junction where a parallel connection is made. Other variations of circuit layouts that provide more or less flexibility in customization and limiting scope of light burn out may be used.
[0029] Many types of energy efficient illumination means are available in the market. In a preferred embodiment, light emitting diodes (LED) are used. The type of LED or equivalents thereof will depend on the required level of luminescence. LEDs consume approximately six to ten times less electricity. With the combination of serial and parallel electrical connections, a burnt out LED will cause light failure of one array only.
[0030] [0030]FIG. 4 a shows the power connector 9 coupling multiple apparatus 1 and delivering electricity to the apparatus 1 . A pin 10 is attached to a terminal 4 . A power connector 11 having couplers 9 is coupled to the pins 10 to make an electrical connection. The same can be used for providing electricity to the apparatus 1 . As shown in FIG. 4 b , the power connectors 11 can be placed on any section 8 of the apparatus. It will be apparent to one skilled in the art that different electrical couplings can be used for coupling apparatus 1 to apparatus 1 , and apparatus 1 to power source.
[0031] Many types of fastener can be used to position the light strip apparatus 1 in place. In one preferred embodiment of the invention as shown in FIG. 5, one part of a Velcro fastener 19 is attached to the bottom of the circuit board 2 in a way that will not cause a short circuit of the lights 3 . The remaining part 20 of the Velcro is attached to any area where the light strips 1 may be placed. However, one skilled in the art will recognize that different types of fasteners—such as snaps, clips or suction cups—can be used.
[0032] As shown in the preferred embodiment of FIG. 6, the receiving portion of the Velcro fastener 20 is attached to the inner wall of the letter ‘C’ 25 . Once the proper length is determined, the light strip 1 is severed to the proper length near the severance line 7 and fastened by the fastener 19 to the attached receiving portion 20 of the Velcro fastener. A power connector 11 is coupled to the power connector pin 10 through which power is supplied.
[0033] [0033]FIG. 6 illustrates the substantial advantage provided by the preferred embodiments of this invention for fitting virtually any sign or lighting fixture. As shown in the preferred embodiment of FIG. 6, the receiving portion of the Velcro fastener 20 is attached to the inner wall of the letter ‘C’ 25 . Once the proper length is determined, the light strip 1 is severed to the proper length near the severance line 7 and fastened by the fastener 19 to the attached receiving portion 20 of the Velcro fastener. A power connector 11 is coupled to the power connector pin 10 through which power is supplied. The ability of the flexible circuit board to bend allows the light strip to precisely conform with the curve of the letter “C” sign. The ease by which the light strips of this invention can be shaped to fit virtually any sign configuration, building facia and the like enables the light strips of this invention to be used in both new signs and installations and for retrofitting to replace neon tubing and other high power usage lighting media. Thus, the preferred embodiments of the present invention have many advantages, including ease and speed of customization and installation.
[0034] [0034]FIG. 7 shows an embodiment of a method of illuminating a sign using the light strip system. The receiving portion 20 of the Velcro fastener is attached to the inner wall of the letter ‘T’ 30 . The light strip 1 is cut to three pieces to fit the sides of the letter ‘T’ 30 and attached to the receiving portion 20 of the Velcro fastener. Power connectors 11 are placed on the power connector pins 10 of each strip 1 . The power connectors 11 between the strips 1 negotiates the sharp angles of the letter ‘T’ 30 to achieve an improved customization of the dimensions of the sign.
[0035] By way of specific example, the LED light strip 1 of FIG. 1 includes a strip 2 of Type FR4 inner core printed circuit board material of approximately ten to twenty thousandth thickness, two arrays 5 of twelve serially connected LEDs placed next to each other width-wise and connected in parallel forming a section 8 . The sections are electrically connected in parallel along the strip 2 , and severance spaces 7 are positioned between the sections 8 . A first portion 19 of a Velcro fastener is cut to the shape of the strip 2 and attached to the bottom of the strip 2 . AC input is drawn from an electrical outlet 15 to a step down transformer 13 to supply 24 volt electrical current to the LED strip 1 . A set of resistors 6 are coupled between the transformer 13 and the LED strip 1 to prevent electrical overload. Electricity is delivered through a power connector 11 in cooperation with the coupler 9 and the pin 10 .
[0036] Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions. | An energy efficient light strip illumination apparatus that can be easily installed with Velcro fasteners for both new installations and retrofitting incandescent and neon installations. One of the preferred embodiments is a flexible strip in which LED array's are imprinted in sections so that the strip can be cut to customize the size of the light strips to fit signs or other lighted features of any size or shape. | 5 |
This application is a continuation of application Ser. No. 376,814, filed May 10, 1982.
BACKGROUND OF THE INVENTION
This invention relates, in general, to MOS transistors, and more particularly, to MOS transistors having a source characterized by low barrier height and low minority carrier injection.
A conventional MOS transistor includes spaced apart source and drain regions formed in a body of semiconductor material. The surface of the semiconductor body between the source and drain regions forms the channel of the transistor. The conductivity of the channel is modulated by the potential on a gate electrode which overlies but is insulated from the semiconductor body. In an N channel MOS transistor, for example, the body of semiconductor material is P type and the source and drain regions are N type regions formed in the body, typically by diffusion, ion implantation, or the like. So formed, the source and drain regions form rectifying PN junctions with the semiconductor body. The term "MOS transistor" is herein used to mean any of the insulated gate field effect transistors regardless of the material used for the gate electrode or gate insulator.
In addition to functioning as a normal MOS transistor, this structure also functions as a particular bippolar transistor with the source, body or channel, and drain functionimg as emittter, base, and collector, respectively. The parasitic bipolar transistor can have adverse effects on the operation of the MOS transistor. If the emitter-base junction of the parasitic bipolar transistor is forwad biased so that the parasiic transistor becomes operative, this can have two undesirable effects on the operation of the MOS transistor. First, the operation of the parasitic bipolar transistor results in the injection of minority carriers into the base of the parasitic device from the emitter. In order to turn off the combination of MOS transistor and parasitic bipolar transistor it is then necessary to sweep these minority carriers out of the base region before the combination of devices is effectively turned off. The time required for sweeping out these minority carriers adversely affects the switching speed of the MOS transistor. The MOS transistor, being a majority carrier device, is generally considered to have an inherently fast switching speed, but the presence of the parasitic bipolar transistor degrades the switching performance so that the inherent speed is not achieved.
Second, the presence of the parasitic bipolar transistor in parallel with the MOS transistor also adversely affects the breakdown performance of the device, especially when the device is used with an inductive load. If the bipolar transistor turns on, the breakdown of the two devices in parallel is dominated by the breakdown of the bipolar transistor in the BV CEO mode. This breakdown is normally much lower than the drain to source breakdown of the MOS transistor, BV DSS . The breakdown voltage problem is especially severe when switching inductive loads, and results in a degradation of safe operating area (SOA) of the device. BV CEO of the bipolar transistor is inversely proportional to the beta of the transistor. Unfortunately, the beta of the parasitic transistor is likely to be quite high, especially with short channel MOS transistors, because of the small amount of doping in the channel region or parasitic base region. Beta cannot easily be reduced to improve on the breakdown problem; beta is dependent upon doping, but the threshold voltage of the MOS transistor is also dependent on this doping and threshold voltage must be controlled to meet the operating requirements of the device. Beta, and thus the BV CEO of the parasitic transistor, therefore cannot be arbitrarily controlled by altering the doping characteristics of the device.
In an attempt to counter these adverse effects, in operating the MOS transistor the source-body potential is controlled and is typically maintained at zero volts. That is, the source and body are electrically shorted together in order to short the emitter and base thereby disabling the parasitic transistor. Because of current flowing through the body or channel of the MOS transistor, however, an internal bias is generated within the device which may be sufficient to forward bias the emitter-base junction of the parasitic transistor despite the intended short circuit.
In some MOS transistors the body of the device is contacted on the back surface of the semiconductor chip. In other devices, such as diffused channel MOS transistors, the body and channel regions are diffused into the top surface of the semiconductor wafer and the source region is then formed within the diffused region. An electrical short between source and channel or body must then be effected on the top surface of the device by metal overlapping the source and body. This usually requires an additional heavily doped contact diffusion to insure good ohmic contact between the metal and the diffused body. The use of a contact diffusion requires additional space and, therefore, decreases the density of MOS transistors that can be achieved. This loss in density is in addition to the above mentioned problems with a parasitic bipolar transistor formed in parallel with the intended MOS transistor.
In view of the foregoing, it is apparent that it would be desirable to provide an improved MOS transistor and method for making that transistor which would overcome the above related and other problems.
Accordingly, it is an object of the present invention to provide an improved MOS transistor having increased switching speeds.
It is another object of this invention to provide an improved MOS transistor having improved safe operating area.
It is yet another object of this invention to provide an improved and higher density MOS transistor.
It is still another object of this invention to provide an improved method for forming an MOS transistor.
BRIEF SUMMARY OF THE INVENTION
The foregoing and other objects are achieved in the present invention through the fabrication of an MOS transistor having a source region which provides majority carriers for device operation with little minority carrier injection and has a low barrier height with respect to the body material. In one embodiment of the invention, a metal silicide source provides both a source of majority carriers to the channel and at the same time provides an ohmic contact to the device body with little minority carrier injection.
BRIEF DESCRIPTION OF THE FIGURES
FIGS. 1 and 2 illustrate conventional MOS transistors;
FIG. 3 illustrates an MOS transistor in accordance with the invention; and
FIGS. 4-9 illustrate process steps for the fabrication of an MOS transistor in accordance with the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 and 2 illustrate, in cross section, the structure of a conventional MOS transistor and a diffused channel MOS transistor, respectively. The devices illustrated are N channel devices, but the following discussion applies equally to N or P channel devices. The devices include a source 20 and drain 22 spaced apart and separated by a channel region 24 of opposite conductivity type. Overlying the channel is a gate electrode 26 insulated from the channel by a gate insulator 28. Current flow between the source and drain is controlled by modulating the conductivity of the channel region by applying gate potentials to the gate electrode through a gate terminal 30.
In FIG. 1 electrical contact is made to source 20 and drain 22 through source and drain terminals 32 and 34, respectively. A body terminal 36 makes electrical contact to metallization 37 on one surface of semiconductor body 38 in which source and drain regions are formed and, through the resistance of body 38, to the channel 24. In normal operation, the potential of the semiconductor body is controlled through terminal 36. Especially in applications of discrete MOS transistors, the source and body are often shorted together as by the electrical interconnection 40 between terminals 32 and 36.
The diffused channel MOS transistor illustrated in FIG. 2 is of the type in which contact to the drain region 22 is made from the back side of the semiconductor device, but similar arguments apply to diffused channel transistors in which the drain contact is on the same side of the wafer as are the contacts to the source and gate. Channel regions 24 are formed by diffusing P type body regions 41 into selected portions of the surface of an N type wafer 42. Source regions 20 are then formed by diffusing a heavily doped N+ region into the P type body region to form a rectifying N+P junction. Channel region 24 is the surface portion of body region 41 located between source and drain and controlled by potential on gate electrode 26. In the embodiment illustrated, the total MOS transistor is formed from a plurality of diffused channels 24 and sources 20 operated in parallel with device current being collected through a single drain terminal 44 making electrical contact to the drain 22. To control the potential in the body, metallization 46 making contact to the source region is patterned to also make contact to the P type channel material. Placing the source metal 46 in such manner effectively shorts source 20 and body 41 together in a manner similar to that done by the innerconnection 40 in FIG. 1. The diffused channel region is lightly doped to provide a desirably low threshold voltage; because of the light surface doping it is difficult to make good ohmic contact to the P region. An additional heavily doped P+ region 48 is therefore required to insure that a low resistance ohmic contact is made to the P type body region.
In each of the devices illustrated in FIGS. 1 and 2 a parasitic bipolar transistor 50 exists in parallel with the intended MOS transistor. The emitter, base, and collector of transistor 50 are formed by the source, body, and drain, respectively, of the MOS transistor. The placing of an electrical short between the source and channel or source and body of the MOS transistor is an attempt to disable this parasitic bipolar transistor by shorting together the base and emitter of the device. Because of resistance internal to the devices, however, this shorting effort is not entirely satisfactory. In transistor 16, for example, a resistance exists through the bulk material 38 between contact 36 and the effective emitter base junction. Similarly, in transistor 18 a resistance exists through the diffused P region between the ohmic contact to P+ region 48 and the operative emitter base junction. Current flow through this resistor during normal operation of the MOS transistor can cause forward biasing of the emitter-base junction despite the intended short.
FIG. 3 illustrates an improved MOS transistor 55 in accordance with the invention which overcomes the above noted difficulties of conventional MOS transistors. In addition, the improved transistor allows the fabrication of higher density devices. Transistor 55 is an N channel MOS transistor of the diffused channel type, but the invention is equally applicable to N or P channel devices whether the channel is diffused or not.
In a structure similar to that of device 18, transistor 55 includes a plurality of diffused P type body regions 41 having channel regions 24 formed at the surface of the P type body regions adjacent an N type drain region 22. Overlying the channel is a gate insulator 28 and a gate electrode 26. Potential on the gate electrode is controlled through a gate terminal 30. Source-drain current flows through N type drain region 22 and is collected at drain contact 44.
In accordance with the invention, source regions 60 of the device are formed, not by diffused N type regions, but by a low minority carrier injecting metal having a low barrier height with respect to the P type channel region. In one embodiment of the invention, source region 60 is formed of a metal silicide wherein the silicide is selected to have a low barrier height with little minority carrier injection. Source region 60 can be formed on P type body 41, for example, by forming a region of platinum silicide, rubidium silicide, iridium silicide, or tungsten silicide. Such silicides have a low barrier height and thus form a good contact to the P doped body region, provide majority carriers for current conduction through the channel region, but are characterized by low minority carrier injection. Because the silicide makes good electrical contact to the diffused P region, an additional heavily doped P+ contact region is not required. Most importantly, however, the low minority carrier injection results in the region being a poor emitter of the parasitic bipolar transistor; the parasitic bipolar transistor, therefore, has low gain and can be neglected as a breakdown voltage determining element. Additionally, because of the low injection, there are few carriers to sweep out during a switching operation and the inherently high switching speeds of MOS transistors are achieved.
The total current injected by the source region into the body or channel region includes both minority and majority carriers. For a device in accordance with the invention having low minority carrier injection, the ratio of minority to majority carriers injected is limited to about 25% and preferably to about 10% or less of that characteristic of an N+P junction. The low ratio of minority to majority carriers is achieved by a metal-silicon contact having a low barrier height. The barrier height of a metal-silicon contact is determined by the work function difference between the metal and the silicon. For a given metal the sum of the barrier height for metal-N type silicon and metal-P type silicon is equal to the silicon energy gap, or about 1.1 ev. Most metals have a high barrier height (0.65 to 0.85 ev) on N type silicon and a correspondingly low barrier height (0.25-0.45 ev) on P type silicon. Preferrably, for devices in accordance with the invention, the barrier height is less than about 0.30 ev. The low barrier height insures good contact between the metal and the body and eliminates the need for a heavily diffused contact region.
FIGS. 4-9 illustrate one process for the fabrication of devices in accordance with the invention. In this illustrative embodiment an N channel device of the diffused channel type is depicted. Those skilled in the art will appreciate that the invention can also be applied, for example, to P channel devices and to devices having an undiffused channel region. It will further be appreciated that in certain process steps the processes of ion implantation and thermal diffusion are interchangeable and that insulating layers can be formed by thermal oxidation, chemical vapor deposition, and the like. With respect to these and other processing steps well known to be generally equivalent, it is intended that the invention not be limited to any one particular choice of such alternatives.
FIG. 4 illustrates a portion of a semiconductor wafer 65 in which a diffused channel MOS transistor in accordance with the invention is to be fabricated. Thick field oxide regions, well known in the art, have not been shown. Substrate 65 is an N type semiconductor wafer, for example, of silicon. The substrate includes a lightly doped N type region 67 having a doping concentration selected to support the desired breakdown voltage of the device. Substrate 65 may also include a heavily doped N+ region 69 to reduce series resistance through the device. Overlying the surface of N region 67 is a thin layer of gate insulator material 71 such as silicon dioxide or other suitable insulator. Overlying the gate insulator is a patterned gate electrode 73 formed of a material such as doped polycrystalline silicon.
FIG. 5 illustrates the formation of a body region 75. The channel is formed by implanting boron ions or other P type dopant into the surface of N type region 67 using gate electrode 73 as an implant mask. By using ion implantation, a carefully controlled amount of dopant can be implanted into the wafer surface. A subsequent heat treatment thermally redistributes the dopant material forming the body region 75 and the channel region 76 at the surface of the body region. The surface concentration of the channel region is a major determinant of the threshold voltage of the MOS transistor and this is determined in known manner by controlling the implant dose and thermal redistribution.
As illustrated in FIG. 6, a masking layer 77, for example silicon dioxide, is formed over the surface of the substrate. It is especially important that edges 79 of the gate electrode be protected by portions 81 of the masking film.
As illustrated in FIG. 7, portions of masking layer 77 and gate insulator 71 are removed to expose surface 83 of the P type body region 75. Patterning of masking layer 77 is done in a manner to insure that portion 81 of the masking layer remains intact covering edges 79 of the gate electrode. The patterning can be accomplished, for example, by reactive ion etching the masking layer. Reactive ion etching is a directionally dependent process in which reactive ions are directed perpendicular to the substrate surface and do not impinge upon or etch sidewall portion 81 positioned on the vertical side of gate electrode 73.
In FIG. 8 a layer of metal 85 having a low barrier height with respect to P type channel region 75 is formed over the surface of the substrate. Layer 85 can be formed, for example, by the sputter deposition of a layer of platinum. Other suitable metals for contacts to a P type region where the contacts are characterized by low barrier height and low minority carrier injection include, for example, rubidium, iridium, and tungsten.
Following the deposition of low barrier height metal 85, the substrate is heated to promote silicide formation between the metal 85 and the P type silicon at surface 83 of body region 75. In the case of platinum, platinum silicide is formed by heating the substrate to a temperature of about 700° C. in a reducing ambient for 15 minutes. Silicide is formed in those locations where the platinum contacts silicon. The silicide formation thus forms source regions 87 and also a low resistance platinum silicide layer 89 atop gate electrode 73 as illustrated in FIG. 9. No silicide forms where the platinum contacts silicon dioxide, for example, on the field oxide and on the mask at the edge of the gate electrode. The platinum can be rinsed off these regions in a suitable etchant without affecting the silicide on other portions of the substrate. Masking layer 81 at the edge of the gate electrode is necessary to prevent any shorting between platinum silicide source 87 and gate electrode 73, especially silicide portion 89 of the gate electrode. This is especially true since a volumetric swelling occurs upon the formation of the silicide and this swelling might otherwise cause shorting between the two transistor regions.
The transistor structure is completed in normal manner, for example, by depositing a layer of insulator over the surface of the device, opening contact windows through that insulator layer, applying electrode material such as aluminum, and patterning the aluminum to form the gate and source electrodes. An electrode material is also applied to the back of the substrate contacting N+ region 69 to serve as the drain contact for the device.
A device in accordance with the invention made as described above is compared to an otherwise similar device fabricated having a diffused source region. Devices are measured to have comparable transconductance, but the device having platinum silicide source regions exhibits greater stability in the breakdown mode without tendency to switch back in a BV CEO mode. A device having platinum silicide source regions is measured to have an improved switching speed when compared to the device having conventional diffused source region.
In this illustrative embodiment, the source regions are formed by depositing platinum and then heating to form platinum silicide. In further embodiments, other metals are deposited in place of the platinum and then heated to form a metal silicide. In yet another embodiment, a metal silicide material is deposited, for example by chemical vapor deposition, to form the source regions. And in yet another embodiment, a metal such as gold is deposited on the semiconductor substrate to form a low barrier height contact without forming a silicide.
Thus it is apparent that there has been provided, in accordance with the invention, an improved MOS transistor and method for making the transistor which fully meets the advantages and objects set forth above. While the invention has been described in relation to certain specific embodiments thereof, it is not intended that the invention be so limited. Other variations and modifications in the invention will be apparent to those skilled in the art after review of the foregoing description. Other low barrier height metals, for example, can be used for the formation of the source region, with or without forming a metal silicide, depending on the metal. Additionally, other processes will be effective in forming particular metal silicides. Accordingly, it is intended to include these and other variations and modifications within the scope of the appended claims. | An improved MOS transistor and method for making that transistor are provided. The improved transistor is characterized by decreased size, improved switching speed, and improved reliability in inductive load use. The improved structure is achieved through the use of a low minority carrier injecting source region formed, for example, by providing a low barrier height metal silicide. The metal silicide source provides a source of majority carriers but little minority carrier injection and hence little parasitic bipolar transistor action. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a wavelength conversion device composed of a semiconductor laser device and a nonlinear optical element having a planar optical waveguide, which are mounted on a substrate in an integrated manner.
2. Related Background Art
In order to realize a high-density optical disk and a high-definition display, small short-wavelength light sources generating a laser beam in a blue range through violet range are desired. Techniques for obtaining a laser beam in this wavelength range include a second harmonic-wave generation method (hereinafter referred to as “SHG”) that employs a wavelength conversion device using a planar optical waveguide according to a quasi-phase-matching method, by which a wavelength of a semiconductor laser can be converted from 850 nm into 425 nm.
To miniaturize a short-wavelength light source according to this method, it is effective to mount a wavelength conversion device and a semiconductor laser device on a substrate in an integrated manner.
FIG. 15 shows one example of these small short-wavelength light sources, which is a wavelength conversion device disclosed in JP 2000-284135 A.
A semiconductor laser device 306 and a planar optical waveguide device 305 are mounted on a silicon substrate 300 in an integrated manner. The planar optical waveguide device 305 functions as a wavelength conversion device structured by forming a proton exchange planar optical waveguide 304 and a diffraction grating (not illustrated) with periodic domain inverted regions formed therein on an Mg doped LiNbO 3 substrate 302 . In addition, on the silicon substrate 300 , electrodes 307 electrically connected to the semiconductor laser device 306 are formed, and alignment keys 301 are formed at positions 10 μm away from the planar optical waveguide 304 . On each side of the planar optical waveguide 304 , alignment keys 303 are formed using a film made of the same material (e.g., Ta) and having the same thickness as those of the alignment keys 301 . Further, alignment keys 308 are formed on the semiconductor laser device 306 as well.
Here, the semiconductor laser device 306 is a Distributed Bragg Reflector (hereinafter, referred to as “DBR”) type semiconductor laser device. As shown in FIG. 15, the electrodes 307 are connected to each of a gain region and a wavelength control region, i.e., a DBR region (not illustrated) of the semiconductor laser device 306 .
The semiconductor laser device 306 and the planar optical waveguide device 305 are mounted onto the silicon substrate 300 in such a manner that a laser beam emitted from the semiconductor laser device 306 is guided through the optical waveguide 304 in the planar optical waveguide device 305 , and the alignment keys 308 , 303 , and 301 are arranged at their predetermined positions. In this wavelength conversion device, a center line M 1 -M 2 of the silicon substrate 300 , a center line M 5 -M 6 of the semiconductor laser device 306 , and a center line M 3 -M 4 of the planar optical waveguide device 305 approximately coincide with one another.
In the future, to miniaturize an optical information processing system employing an optical disk and a display still more than present ones, an optical pick up unit included in an optical disk or the like needs to be made small. To this end, it becomes effective to make a wavelength conversion device smaller.
Meanwhile, when electrically driving such a wavelength conversion device, an oscillation wavelength of a laser beam emitted from the semiconductor laser device 306 needs to be controlled so as to maximize a conversion efficiency of the laser beam by the SHG.
In the wavelength conversion device shown in FIG. 15, by controlling a current applied to the electrode connected to the DBR region, among the electrodes 307 , a refractive index of the DBR region is varied so as to change a Bragg wavelength, whereby the oscillation wavelength is controlled. In this wavelength conversion device, however, a phase of the emitted laser beam cannot be controlled, because the semiconductor laser device 306 consists of only two regions, i.e., the gain region and the DBR region. Due to such a constraint, if a Bragg wavelength in the DBR region is varied by the passage of the electric current, then a so-called mode hoping would occur, where the oscillation wavelength changes discontinuously. In this case, it becomes difficult to control the oscillation wavelength, which might interfere with the operation of the device significantly.
SUMMARY OF THE INVENTION
Therefore, with the foregoing in mind, it is an object of the present invention to provide a small short-wavelength conversion device composed of a semiconductor laser device and an optical waveguide device, which are mounted on a substrate in an integrated manner.
To fulfill the above-stated object, a wavelength conversion device according to an embodiment of the present invention, which converts a wavelength by second harmonic-wave generation and generates a laser beam, includes: a substrate having a plurality of electrodes; a semiconductor laser device mounted on the substrate and electrically connected to the plurality of electrodes; and a nonlinear optical element having an optical waveguide for guiding a laser beam emitted from the semiconductor laser device and for converting a wavelength of the laser beam. Here, the nonlinear optical element is mounted on the substrate in such a manner that the optical waveguide in the nonlinear optical element is located away from the center line of the substrate.
To fulfill the above-stated object, a wavelength conversion device according to another embodiment of the present invention, which converts a wavelength by second harmonic-wave generation and generates a laser beam, includes: a substrate having a plurality of electrodes; a semiconductor laser device electrically connected to the plurality of electrodes; and a nonlinear optical element having an optical waveguide for guiding a laser beam emitted from the semiconductor laser device and for converting a wavelength of the laser beam. Here, the semiconductor laser device, the optical waveguide of the nonlinear optical element, and the plurality of electrodes are on approximately one line on the substrate.
It is another object of the present invention to provide a wavelength conversion device by which an oscillation wavelength of a laser beam emitted from a semiconductor laser device can be controlled with stability.
To fulfill the above-stated object, a wavelength conversion device according to an embodiment of the present invention, which converts a wavelength by second harmonic-wave generation and generates a laser beam, includes: a substrate having a plurality of electrodes; a semiconductor laser device mounted on the substrate and including three regions of a gain region, a phase control region, and a wavelength control region; and a nonlinear optical element mounted on the substrate and for converting a wavelength of a laser beam emitted from the semiconductor laser device. Here, the plurality of electrodes include a first electrode group formed corresponding to the three regions and a second electrode group for carrying out wire-bonding with an external power source, the three regions of the semiconductor laser device are connected electrically to the respective electrodes in the first electrode group, and the first electrode group further is connected to the respective electrodes in the second electrode group via wires, and a wire among the wires, which is connected between the phase control region and the wavelength control region of the semiconductor laser device, has a portion functioning as a resistor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a wavelength conversion device according to Embodiment 1;
FIG. 2 is a plan view of a wavelength conversion device according to Embodiment 2;
FIG. 3 is a plan view of a wavelength conversion device according to Embodiment 3;
FIG. 4 is a plan view of a wavelength conversion device according to Embodiment 4;
FIG. 5 is a plan view of a wavelength conversion device according to Embodiment 5;
FIG. 6 is a plan view of a wavelength conversion device according to Embodiment 6;
FIG. 7 is a plan view of a wavelength conversion device according to Embodiment 7;
FIG. 8 is a plan view of a wavelength conversion device according to Embodiment 8;
FIG. 9 is a plan view of a wavelength conversion device according to Embodiment 9;
FIG. 10 is a plan view of a wavelength conversion device according to Embodiment 10;
FIG. 11 is a plan view of a wavelength conversion device according to Embodiment 11;
FIG. 12 is a plan view of a wavelength conversion device according to Embodiment 12;
FIG. 13 is a graph showing the relationship among oscillation longitudinal mode orders, and amount of current fed into a phase control region and a DBR region;
FIG. 14 is a circuit diagram showing a state where the phase control region and the DBR region of the semiconductor laser device are driven at the same voltage; and
FIG. 15 is a plan view of a wavelength conversion device according to the prior art.
DETAILED DESCRIPTION OF THE INVENTION
The following describes embodiments of the present invention, with reference to the drawings.
[Embodiment 1]
FIG. 1 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate (3 mm in width, 15 mm in length), electrodes 1 , 2 , and 3 are formed by patterning, and a DBR laser element 4 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 7 (2.8 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 6 denotes an optical waveguide, and 8 denotes a diffraction grating formed in the optical waveguide 6 . Line 100 is a center line of the optical waveguide 6 . Line M 1 a -M 2 a is a center line of the width direction of the silicon substrate 5 , and line M 5 a -M 6 a is a center line of the width direction of the nonlinear optical element 7 . Hereinafter, in the wavelength conversion devices according to the present invention, the direction perpendicular to the optical waveguide is referred to as the width direction, while the direction parallel to the optical waveguide is referred to as the longitudinal direction.
The DBR laser element 4 is made up of three regions including a gain region that adjusts an output power of a laser beam emitted therefrom, a phase control region that changes a phase of the laser beam, and a DBR region that feeds back a laser beam with an oscillation wavelength into a cavity. Note here that these regions referred to in this embodiment or later in this specification have the functions as stated above.
With respect to these three regions, electrodes that are electrically isolated from one another are formed (not illustrated). The DBR laser element 4 is mounted on the silicon substrate 5 in a junction down manner where a surface with the p-n junction faces to the side of the silicon substrate 5 , and electrodes corresponding to the gain region, the phase control region, and the DBR region are bonded to the electrodes 1 , 2 , and 3 on the silicon substrate 5 , respectively. Also, wire-bonding regions are formed in each of the electrodes for carrying out wiring with an external power source so as to electrically drive the gain region, the phase control region, and the DBR region.
In this way, the gain region, the phase control region, and the DBR region of the DBR laser element 4 are connected electrically to the electrodes 1 , 2 , and 3 , respectively. In this state, by feeding an electrical signal to each of the electrodes, an oscillation wavelength of the laser beam emitted from the DBR laser element 4 can be varied. The oscillation wavelength of the laser beam emitted from the DBR laser element 4 is set at 820 nm, and the beam is oscillated in the single longitudinal mode.
The nonlinear optical element 7 is made of LiNbO 3 , and the optical waveguide 6 having the diffraction grating 8 is formed therein. The nonlinear optical element 7 is fixed onto the silicon substrate 5 at a predetermined position with an adhesive such as a UV curing agent.
The diffraction grating 8 is formed by inverting a polarization of LiNbO 3 crystals with the application of an external electric field. The optical waveguide 6 is positioned within 3 μm of the DBR laser element 4 so as to introduce the laser beam emitted from the DBR laser element 4 securely.
When guiding the laser beam through the optical waveguide 6 , a second harmonic-wave generated beam (hereinafter, referred to as “SHG beam”) with a wavelength of 410 nm generated in the nonlinear optical element 7 due to a diffraction by the diffraction grating 8 and the laser beam with an oscillation wavelength of 820 nm are quasi-phase matched. Thereby, an SHG beam having a high output power can be obtained. In addition, by controlling the oscillation wavelength of the laser beam emitted from the DBR laser element 4 , a conversion efficiency into the SHG beam can be improved.
In this embodiment, as shown in FIG. 1, the nonlinear optical element 7 is mounted on the silicon substrate 5 in such a manner that the center line 100 of its optical waveguide 6 is 1.0 mm away from the center line M 1 a -M 2 a of the silicon substrate 5 . In this way, in this embodiment, the optical waveguide 6 does not necessarily need to be formed on the center line M 5 a -M 6 a of the nonlinear optical element 7 .
In addition, the nonlinear optical element 7 is mounted so that the center line M 1 a -M 2 a of the silicon substrate 5 coincides with the center line M 5 a -M 6 a of the nonlinear optical element 7 in FIG. 1 . However, these center lines do not necessarily coincide with each other.
Furthermore, the end of the optical waveguide 6 at the side of the nonlinear optical element 7 where the SHG beam is emitted is located at least 5 μm beyond the edge of the silicon substrate 5 . This construction prevents the SHG beam from being reflected from the silicon substrate 5 and scattered, and therefore a favorable image can be obtained in the far field for the SHG beam emitted from the nonlinear optical element 7 .
According to this embodiment, since the nonlinear optical element 7 is mounted on the substrate in such a manner that its optical waveguide 6 is located away from the center line M 1 a -M 2 a of the silicon substrate 5 , the width of the wavelength conversion device can be narrowed to 5 μmm or less, and therefore a small wavelength conversion device having approximately the same size as the nonlinear optical element 7 can be realized.
[Embodiment 2]
FIG. 2 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 5 (2 mm in width, 6 mm in length), electrodes 1 , 2 , and 3 are formed by patterning, and a DBR laser element 4 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 7 (2.8 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 6 denotes an optical waveguide, and 8 denotes a diffraction grating formed in the optical waveguide 6 . Line 100 is a center line of the optical waveguide 6 . Line M 1 b -M 2 b is a center line of the width direction of the silicon substrate 5 , and line M 5 b -M 6 b is a center line of the width direction of the nonlinear optical element 7 . In this way, the construction of the wavelength conversion device in this embodiment is similar to that of the wavelength conversion device according to Embodiment 1, except that the silicon substrate 5 is miniaturized so that a length of a region where the DBR laser element 4 is mounted on the silicon substrate 5 is 3 mm along the longitudinal direction of the silicon substrate 5 , and the nonlinear optical element 7 is mounted on the substrate so that the center line 100 of its optical wavelength 6 is 0.7 mm away from the center line of the silicon substrate 5 . That is, in this embodiment also, the nonlinear optical element 7 is positioned within 3 μm of the DBR laser element 4 so as to introduce the laser beam emitted from the DBR laser element 4 securely, and the end of the optical waveguide 6 at the side where the SHG beam is emitted is located at least 5 μm beyond the edge of the silicon substrate 5 . Therefore, their explanations will be omitted.
According to this embodiment, the same effects as in Embodiment 1 can be obtained. In addition, by reducing the length of the silicon substrate 5 , the region where the nonlinear optical element 7 is mounted on the silicon substrate 5 is narrowed. Therefore, distortion generated due to the contact between the nonlinear optical element 7 and the silicon substrate 5 can be reduced, and a conversion efficiency from the laser beam emitted from the DBR laser element 4 into the SHG beam can be improved.
[Embodiment 3]
FIG. 3 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 5 (3.0 mm in width, 12 mm in length), electrodes 9 , 10 , and 11 are formed by patterning, and a DBR laser element 4 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 7 (2.8 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 6 denotes an optical waveguide, and 8 denotes a diffraction grating formed in the optical waveguide 6 . Line 100 is a center line of the optical waveguide 6 . Line M 1 c -M 2 c is a center line of the width direction of the silicon substrate 5 , and line M 5 c -M 6 c is a center line of the width direction of the nonlinear optical element 7 .
The DBR laser element 4 is made up of three regions including a gain region, a phase control region, and a DBR region.
With respect to these three regions, electrodes that are electrically isolated from one another are formed (not illustrated). The DBR laser element 4 is mounted on the silicon substrate 5 in a junction down manner where a surface with the p-n junction faces to the side of the silicon substrate 5 , and electrodes corresponding to the gain region, the phase control region, and the DBR region are bonded to regions 9 b, 10 b , and 11 b of the electrodes 9 , 10 , and 11 , respectively.
Also, wire-bonding regions 9 a , 10 a , and 11 a are formed in each of the electrodes 9 , 10 , and 11 for carrying out wiring with an external power source so as to electrically drive the gain region, the phase control region, and the DBR region of the DBR laser element 4 . Here, widths of portions formed between these wire-bonding regions and regions 9 b , 10 b , and 11 b (hereinafter, refered to as “connection regions”, which are connected to the respective electrodes formed in the three regions in the DBR laser element 4 ) are narrower than those of the wire-bonding regions and the connection regions. In this way, by partially narrowing the width of each of the electrodes formed on the silicon substrate 5 , the parasitic capacitance of these electrodes can be reduced.
As stated above, the construction of the wavelength conversion device according to this embodiment is similar to that of the wavelength conversion device according to Embodiment 1, except that the width of each electrode formed on the silicon substrate 5 is narrowed in part, and the nonlinear optical element 7 is mounted on the substrate so that the center line 100 of its optical wavelength 6 is 1.0 mm away from the center line of the silicon substrate 5 . That is, in this embodiment also, the nonlinear optical element 7 is positioned within 3 μm of the DBR laser element 4 , and the end of the optical waveguide 6 at the side where the SHG beam is emitted is located at least 5 μm beyond the edge of the silicon substrate 5 . Therefore, their explanations will be omitted.
According to this embodiment, the same effects as in Embodiment 1 can be obtained. In addition, by partially narrowing the width of each electrode formed on the silicon substrate 5 , the parasitic capacitance of these electrodes can be reduced, and therefore an electrical modulation frequency of the DBR laser element 4 can be increased.
[Embodiment 4]
FIG. 4 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 5 (2.0 mm in width, 6.0 mm in length), electrodes 9 , 10 , and 11 are formed by patterning, and a DBR laser element 4 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 7 (2.8 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 6 denotes an optical waveguide, and 8 denotes a diffraction grating formed in the optical waveguide 6 . Line 100 is a center line of the optical waveguide 6 . Line M 1 d -M 2 d is a center line of the width direction of the silicon substrate 5 , and line M 5 d -M 6 d is a center line of the width direction of the nonlinear optical element 7 .
The DBR laser element 4 is made up of three regions including a gain region, a phase control region, and a DBR region.
With respect to these three regions, electrodes that are electrically isolated from one another are formed (not illustrated). The DBR laser element 4 is mounted on the silicon substrate 5 in a junction down manner where a surface with the p-n junction faces to the side of the silicon substrate 5 , and electrodes corresponding to the gain region, the phase control region, and the DBR region are bonded to regions 9 b , 10 b , and 11 b of the electrodes 9 , 10 , and 11 , respectively.
Also, wire-bonding regions 9 a , 10 a , and 11 a are formed in each of the electrodes 9 , 10 , and 11 for carrying out wiring with an external power source so as to electrically drive the gain region, the phase control region, and the DBR region of the DBR laser element 4 . Here, widths of portions formed between these wire-bonding regions and regions 9 b , 10 b , and 11 b (hereinafter, referred to as “connection regions”, which are connected to the respective electrodes formed in the three regions n the DBR laser element 4 ) are narrower than those of the wire-bonding regions and the connection regions. In this way, by partially narrowing the width of each of the electrodes formed on the silicon substrate 5 , the parasitic capacitance of these electrodes can be reduced. As stated above, the construction of the wavelength conversion device according to this embodiment is similar to that of the wavelength conversion device according to Embodiment 1, except that the silicon substrate 5 is miniaturized so that a length of a region where the DBR laser element 4 is mounted on the silicon substrate 5 is 3 mm along the longitudinal direction of the silicon substrate 5 , the nonlinear optical element 7 is mounted on the substrate so that the center line 100 of its optical wavelength 6 is 0.7 mm away from the center line of the silicon substrate 5 , and the width of each electrode formed on the silicon substrate 5 is narrowed in part. That is, in this embodiment also, the nonlinear optical element 7 is positioned within 3 μm of the DBR laser element 4 , and the end of the optical waveguide 6 at the side where the SHG beam is emitted is located at least 5 μm beyond the edge of the silicon substrate 5 . Therefore, their explanations will be omitted.
According to this embodiment, the same effects as in Embodiment 1 can be obtained. In addition, by reducing the length of the silicon substrate 5 , the region where the optical element 7 is mounted on the silicon substrate 5 is narrowed. Therefore, distortion generated in the optical waveguide 6 due to the contact between the nonlinear optical element 7 and the silicon substrate 5 can be reduced, and a conversion efficiency from the laser beam emitted from the DBR laser element 4 into the SHG beam can be improved. Furthermore, by partially narrowing the width of each electrode formed on the silicon substrate 5 , the parasitic capacitance of these electrodes can be reduced, and therefore an electrical modulation frequency of the DBR laser element 4 can be increased.
[Embodiment 5]
FIG. 5 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 112 (3 mm in width, 15 mm in length), electrodes 101 , 102 , 103 , 104 , 105 , and 106 are formed by patterning, and a DBR laser element 107 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 115 (2.8 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 110 denotes an optical waveguide, and 111 denotes a diffraction grating formed in the optical waveguide 110 . Line 100 is a center line of the optical waveguide 110 .
The DBR laser element 107 is made up of three regions including a gain region, a phase control region, and a DBR region.
With respect to these three regions, electrodes that are electrically isolated from one another are formed (not illustrated). The DBR laser element 107 is mounted on the silicon substrate 112 in a junction down manner where a surface with the p-n junction faces to the side of the silicon substrate 112 , and electrodes corresponding to the gain region, the phase control region, and the DBR region are bonded to the electrodes 101 , 102 , and 103 (hereinafter called “connection electrodes”), respectively.
Electrodes 104 , 105 , and 106 are wire-bonding electrodes for carrying out wiring with an external power source so as to electrically drive the gain region, the phase control region, and the DBR region, respectively. Then, these wire-bonding electrodes and the connection electrodes formed corresponding to the respective regions in the DBR laser element 107 are connected with each other by wires 13 a , 13 b , and 13 c , respectively. In this state, by feeding an electrical signal to each of the connection electrodes, an oscillation wavelength of the laser beam emitted from the DBR laser element 107 can be varied. The oscillation wavelength of the laser beam emitted from the DBR laser element 107 is set at 820 nm, and the beam is oscillated in the single longitudinal mode.
The nonlinear optical element 115 is made of LiNbO 3 , and the optical waveguide 110 having the diffraction grating 111 is formed therein. The nonlinear optical element 115 is fixed onto the silicon substrate 112 at a predetermined position with an adhesive such as a UV curing agent.
The diffraction grating 111 is formed by inverting a polarization of LiNbO 3 crystals with the application of an external electric field. The optical waveguide 110 is positioned within 3 μm of the DBR laser element 107 so as to introduce the laser beam emitted from the DBR laser element 107 securely.
When guiding the laser beam through the optical waveguide 110 , an SHG beam with a wavelength of 410 nm generated due to a diffraction by the diffraction grating 111 and the laser beam with an oscillation wavelength of 820 nm are quasi-phase matched. Thereby, an SHG beam having a high output power can be obtained. In addition, by controlling the oscillation wavelength of the laser beam emitted from the DBR laser element 107 , a conversion efficiency from the laser beam into the SHG beam can be improved.
In this embodiment, the DBR laser element 107 , the optical waveguide 110 of the nonlinear optical element 115 , and the electrodes 101 through 106 are arranged on the line 100 on the silicon substrate 112 .
Furthermore, the end of the optical waveguide 110 in the nonlinear optical element 115 at the side where the SHG beam is emitted is located at least 5 μm beyond the edge of the silicon substrate 112 . This construction prevents the SHG beam from being reflected from the silicon substrate 112 and scattered, and therefore a favorable image can be obtained in the far field for the SHG beam emitted from the nonlinear optical element 115 .
According to this embodiment, since the DBR laser element 107 , the optical waveguide 110 of the nonlinear optical element 115 , and the electrodes 101 through 106 are arranged on the line 100 on the silicon substrate 112 , the width of the wavelength conversion device can be narrowed to 5 mm or less, and therefore a wavelength conversion device having a width approximately the same as the width of the nonlinear optical element 115 can be obtained.
[Embodiment 6]
FIG. 6 is a plan view of a wavelength conversion device according to this embodiment. The construction of the wavelength conversion device according to this embodiment is similar to that of the wavelength conversion device according to Embodiment 5, except that the length of the silicon substrate 112 is made 6 mm, which is less than half the length of the silicon substrate 112 in Embodiment 5 (15 mm), and that a length of a region where the DBR laser element 107 is mounted on the silicon substrate 112 is 3 mm along the longitudinal direction of the silicon substrate 112 . That is, in this embodiment also, the nonlinear optical element 115 is positioned within 3 μm of the DBR laser element 107 . Therefore, their explanations will be omitted.
According to this embodiment, the same effects as in Embodiment 5 can be obtained. In addition, by reducing the length of the silicon substrate 112 , the silicon substrate 112 can be miniaturized, and therefore the wavelength conversion device can be miniaturized and the cost can be reduced. Furthermore, by narrowing the region where the optical element 115 is mounted on the silicon substrate 112 , distortion of the optical waveguide 110 generated due to the contact between the nonlinear optical element 115 and the silicon substrate 112 can be reduced, and a conversion efficiency from the laser beam emitted from the DBR laser element 107 into the SHG beam can be improved.
[Embodiment 7]
FIG. 7 is a plan view of a wavelength conversion device according to this embodiment. The construction of the wavelength conversion device according to this embodiment is similar to that of the wavelength conversion device according to Embodiment 6, except that the width of the silicon substrate 112 is made to be 2.5 mm, which is narrowed by 0.5 mm versus that in Embodiment 6 (3 mm). That is, in this embodiment also, a length of a region where the DBR laser element 107 is mounted on the silicon substrate 112 is 3 mm along the longitudinal direction of the silicon substrate 112 , and the nonlinear optical element 115 is positioned within 3 μm of the DBR laser element 107 . Therefore, their explanations will be omitted.
According to this embodiment, the same effects as in Embodiment 6 can be obtained. In addition, the silicon substrate 112 further can be miniaturized, and therefore the wavelength conversion device can be miniaturized and the cost can be reduced.
[Embodiment 8]
FIG. 8 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 112 (3 mm in width, 15 mm in length), electrodes 101 , 102 , 103 , 104 , 105 , and 106 are formed by patterning, and a DBR laser element 107 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 115 (1.5 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 110 denotes an optical waveguide, and 111 denotes a diffraction grating formed in the optical waveguide 110 . Line 100 is a center line of the optical waveguide 110 . Line M 100 -M 200 is a center line of the width direction of the silicon substrate 112 and line M 500 -M 600 is a center line of the width direction of the nonlinear optical element 115 .
In this embodiment, the DBR laser element 107 , the optical waveguide 110 of the nonlinear optical element 115 , and the electrodes 101 through 106 are arranged on the line 100 on the silicon substrate 112 , and connection wires 13 a , 13 b , and 13 c are connected to the electrodes 101 through 103 at the same side thereof so as to extend in the longitudinal direction of the silicon substrate 112 . Also, the width of the silicon substrate 112 is made to be 2 mm, which is narrowed by 0.5 mm versus that in Embodiment 7 (2.5 mm).
In addition, the nonlinear optical element 115 is mounted on the silicon substrate 112 in such a manner that the center line 100 of its optical waveguide 110 is 0.5 mm away from the center line M 100 -M 200 of the silicon substrate 112 and 0.3 mm away from the center line M 500 -M 600 of the nonlinear optical element 115 . Thereby, the width of the nonlinear optical element 115 is narrowed further to 1.5 mm from 2.0 mm.
In the same manner as in Embodiment 7, a length of a region where the DBR laser element 107 is mounted on the silicon substrate 112 is 3 mm along the longitudinal direction of the silicon substrate 112 , and the nonlinear optical element 115 is positioned within 3 μm of the DBR laser element 107 .
According to this embodiment, the same effects as in Embodiment 7 can be obtained. In addition, with the construction where the connection wires 13 a , 13 b , and 13 c are connected to the electrodes 101 through 103 at the same side thereof on the silicon substrate 112 , and the nonlinear optical element 115 is mounted on the silicon substrate 112 in such a manner that the optical waveguide 110 is away from the center line M 100 -M 200 of the silicon substrate 112 and away from the center line of the nonlinear optical element 115 , regions where any components and wires are not formed on the silicon substrate 112 can be reduced, and the width of the silicon substrate 112 can be narrowed, and therefore a wavelength conversion device using the same can be miniaturized.
[Embodiment 9]
FIG. 9 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 212 (3 mm in width, 15 mm in length), electrodes 201 , 202 , 203 , 204 , and 205 are formed by patterning, and a DBR laser element 207 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 215 (2.8 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 210 denotes an optical waveguide, and 211 denotes a diffraction grating formed in the optical waveguide 210 . Line 100 is a center line of the optical waveguide 210 .
The DBR laser element 207 is made up of three regions including a gain region, a phase control region, and a DBR region.
With respect to these three regions of the DBR laser element 207 , electrodes that are electrically isolated from one another are formed (not illustrated). The DBR laser element 207 is mounted on the silicon substrate 212 in a junction down manner where a surface with the p-n junction faces to the side of the silicon substrate 212 , and electrodes corresponding to the gain region, the phase control region, and the DBR region are bonded to the electrodes 201 , 202 , and 203 (connection electrodes), respectively.
Electrodes 204 and 205 are wire-bonding electrodes for carrying out wiring with an external power source so as to electrically drive the gain region, the phase control region, and the DBR region, respectively. Then, these wire-bonding electrodes and the connection electrodes formed corresponding to the respective regions in the DBR laser element 207 are connected with each other by wires 214 and 213 . Here, the wire 214 is connected to the gain region, and the wire 213 is connected to the phase control region and the DBR region. The wire 214 is made of metal, and the wire 213 is made of p-type polysilicon with a resistor 213 a formed at a portion thereof.
In this state, by feeding an electrical signal to each of the connection electrodes, an oscillation wavelength of the laser beam emitted from the DBR laser element 207 can be varied. By varying a voltage applied across the electrode 205 , a current fed into the gain region in the DBR laser element 207 can be controlled, and thus an output power of the laser beam can be controlled. The oscillation wavelength of the laser beam emitted from the DBR laser element 207 is set at 820 nm, and the beam is oscillated in the single longitudinal mode.
The nonlinear optical element 215 is made of LiNbO 3 , and the optical waveguide 210 having the diffraction grating 211 is formed therein. The nonlinear optical element 215 is fixed onto the silicon substrate 212 at a predetermined position with an adhesive such as a UV curing agent.
The diffraction grating 211 is formed by inverting a polarization of LiNbO 3 crystals with the application of an external electric field. The optical waveguide 210 is positioned within 3 μm of the DBR laser element 207 so as to introduce the laser beam emitted from the DBR laser element 207 securely.
When guiding the laser beam through the optical waveguide 210 , an SHG beam with a wavelength of 410 nm generated due to a diffraction by the diffraction grating 211 and the laser beam with an oscillation wavelength of 820 nm are quasi-phase matched. Thereby, an SHG beam having a high output power can be obtained. In addition, by controlling the oscillation wavelength of the laser beam emitted from the DBR laser element 207 , a conversion efficiency from the laser beam into the SHG beam can be improved.
In this embodiment, the DBR laser element 207 , the optical waveguide 210 of the nonlinear optical element 215 , and the electrodes 201 through 205 are arranged on the line 100 on the silicon substrate 212 . With this construction, the width of the wavelength conversion device can be narrowed to 5 mm or less, and a small wavelength conversion device having approximately the same width as the nonlinear optical element 215 can be realized.
By providing the DBR laser element 207 with the phase control region, in addition to the gain region and the DBR region, so-called mode hopping can be prevented, and thus the oscillation wavelength can be controlled continuously. Unlike the gain region, the phase control region is a region from which gain is not obtained by the passage of electric current. In addition, the phase control region does not have a wavelength selectivity, because it is not provided with a diffraction grating as in the DBR region. When passing electric current through the phase control region, an effective refractive index in the optical waveguide within the region varies, and therefore a phase of the laser beam at a resonant state can be changed.
FIG. 13 is a graph showing a relationship among oscillation longitudinal mode orders, amount of current fed into the phase control region and the DBR region in an AlGaAs class laser element. When injecting an electric current into the DBR region, the effective refractive index is increased, and the Bragg wavelength is shifted to the long wavelength side. Therefore, the oscillation longitudinal mode order mode-hops from the N-th to N−1-th, i.e., to the lower order. Meanwhile, when injecting an electric current into the phase control region, the effective refractive index is increased, and the effective cavity length is increased. Therefore, the oscillation longitudinal mode order mode-hops from the N-th to N+1-th, i.e., to the higher order.
Consequently, as shown by the broken line in FIG. 13 where a ratio of the current injected into the DBR region to that into the phase control region is kept constant, when injecting an electrical current into the DBR region, the Bragg wavelength is shifted to the long wavelength side, and the oscillation wavelength whose mode gain is the highest is shifted to the long wavelength side. When injecting an electric current into the phase control region, the effective refractive index in this region is increased, and the effective resonator length is increased. Therefore, even when the oscillation wavelength shifts to the longer wavelength side, the oscillation at the same N-th longitudinal mode can be kept in the same phase state, and thus mode hopping can be prevented.
FIG. 14 is a circuit diagram showing a state where resistors are connected in series to each of the phase control region 401 a and the DBR region 401 b in the semiconductor laser device 401 and the respective regions are driven with the same bias voltage applied by the power source 404 . In such a state, current injected into the phase control region and the DBR region has the relationship as represented by the following formula (1).
I DBR =( R 2 +R DBR )/( R 1 +R PHASE )× I PHASE (1)
Here, I PHASE and I DBR are currents injected into the phase control region and the DBR region, respectively. R 1 and R PHASE are a value of differential resistance of the phase control region (constant value) and a value of resistance of the resistor 402 connected to the phase control region, respectively, while R 2 and R DBR are a value of differential resistance of the DBR region (constant value) and a value of resistance of the resistor 403 connected to the DBR region, respectively.
Therefore, as shown by Formula (1), by varying the values of R PHASE and R DBR connected to the phase control region and the DBR region, a ratio between the current I DBR and I PHASE (i.e., (R 2 +R DBR )/(R 1 +R PHASE ), hereinafter, referred to as a ratio between currents) can be controlled.
In this embodiment, as shown in FIG. 9, the resistor 213 a is formed at a portion of the wire connected between the phase control region and the DBR region in the semiconductor laser device. Assuming that the resistor 213 a has a value of resistance represented by R, the ratio between currents becomes I DBR /I PHASE =(R 2 +R)/(R 1 +R). Therefore, by adjusting the value R of the resistor 213 a so that the oscillation longitudinal mode orders does not generate mode-hopping, the oscillation wavelength of the laser beam emitted from the semiconductor laser device can be varied continuously. Note here that the value of R preferably is set within a range between 10 −3 Ω·cm and 10 6 Ω·cm.
According to this embodiment, by providing a portion of the wire connected between the phase control region and the DBR region with a function as a resistor and adjusting the value of the resistor, the oscillation wavelength of the laser beam emitted from the semiconductor laser device can be controlled with stability.
[Embodiment 10]
FIG. 10 is a plan view of a wavelength conversion device according to this embodiment. The construction of the wavelength conversion device is similar to that of the wavelength conversion device according to Embodiment 9, except that the length of the silicon substrate 212 in the longitudinal direction is made to be 6 mm, which is a half or less of the length in Embodiment 9 (15 mm), the length of a region where the DBR laser element 207 is mounted on the silicon substrate 212 in the longitudinal direction of the silicon substrate 212 is 3 mm, and the width of the silicon substrate 212 is made to be 2 mm, which is narrowed by 1 mm from the width of the silicon substrate 212 in Embodiment 9 (3 mm). That is, in this embodiment also, the nonlinear optical element 215 is positioned within 3 μm of the DBR laser element 207 . Therefore, their explanations will be omitted.
According to this embodiment, the same effects as in Embodiment 9 can be obtained. In addition, by reducing the length of the silicon substrate 212 , the silicon substrate 212 can be miniaturized, and therefore the wavelength conversion device can be miniaturized and the cost can be reduced. Furthermore, by narrowing the region where the optical element 215 is mounted on the silicon substrate 212 , distortion of the optical waveguide 210 generated due to the contact between the nonlinear optical element 215 and the silicon substrate 212 can be reduced, and a conversion efficiency from the laser beam emitted from the DBR laser element 207 into the SHG beam can be improved.
[Embodiment 11]
FIG. 11 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 212 (3.2 mm in width, 11.5 mm in length), electrodes 221 , 222 , 223 , 224 , and 225 are formed by patterning, and a DBR laser element 227 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 215 (3 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 210 denotes an optical waveguide, and 211 denotes a diffraction grating formed in the optical waveguide 210 . Line 100 is a center line of the optical waveguide 210 . Line M 10 a -M 20 a is a center line of the width direction of the silicon substrate 212 and line M 50 a -M 60 a is a center line of the width direction of the nonlinear optical element 215 .
The DBR laser element 227 is made up of three regions including a gain region, a phase control region, and a DBR region.
With respect to these three regions, electrodes that are electrically isolated from one another are formed (not illustrated). The DBR laser element 227 is mounted on the silicon substrate 212 in a junction down manner where a surface with the p-n junction faces to the side of the silicon substrate 212 , and electrodes corresponding to the gain region, the phase control region, and the DBR region are bonded to the electrodes 221 , 222 , and 223 (connection electrodes), respectively.
Electrodes 224 and 225 are wire-bonding electrodes for carrying out wiring with an external power source so as to electrically drive the gain region, the phase control region, and the DBR region, respectively. Then, a wire 214 is connected between the electrodes 221 and 224 , and a wire 213 is connected among the electrodes 222 and 223 , and 225 . The wire 214 is made of metal, and the wire 213 is made of p-type polysilicon with a resistor 213 a formed at a portion thereof.
In this state, by feeding an electrical signal to each of the connection electrodes, an oscillation wavelength of the laser beam emitted from the DBR laser element 227 can be varied. By varying a voltage applied across the electrode 224 , a current fed into the gain region in the DBR laser element 227 can be controlled, and thus an output power of the laser beam can be controlled. The oscillation wavelength of the laser beam emitted from the DBR laser element 227 is set at 820 nm, and the light is oscillated in the single longitudinal mode.
The nonlinear optical element 215 is made of LiNbO 3 , and the optical waveguide 210 having the diffraction grating 211 is formed therein. The nonlinear optical element 215 is fixed onto the silicon substrate 212 at a predetermined position with an adhesive such as a UV curing agent.
The diffraction grating 211 is formed by inverting a polarization of LiNbO 3 crystals with the application of an external electric field. The optical waveguide 210 is positioned within 3 μm of the DBR laser element 227 so as to introduce the laser beam emitted from the DBR laser element 227 securely.
When guiding the laser beam through the optical waveguide 210 , an SHG beam with a wavelength of 410 nm generated due to a diffraction by the diffraction grating 211 and the laser beam with an oscillation wavelength of 820 nm are quasi-phase matched. Thereby, an SHG beam having a high output power can be obtained. In addition, by controlling the oscillation wavelength of the laser beam emitted from the DBR laser element 227 , a conversion efficiency from the laser beam into the SHG beam can be improved.
In this embodiment, as shown in FIG. 11, the nonlinear optical element 215 is mounted on the substrate in such a manner that the center line 100 of its optical waveguide 210 is located 1.0 mm away from the center line M 10 a -M 20 a of the silicon substrate 212 . In this way, the optical waveguide 210 does not necessarily need to be formed on the center line M 50 a -M 60 a of the nonlinear optical element 215 .
In addition, although the nonlinear optical element is mounted on the substrate in such a manner that the center line M 10 a -M 20 a of the silicon substrate 212 coincides with the center line M 50 a -M 60 a of the nonlinear optical element 215 , these center lines do not necessarily need to be aligned.
Furthermore, the end of the optical waveguide 210 at the side of the optical waveguide 210 where the SHG beam is emitted is located at least 5 μm beyond the edge of the silicon substrate 212 . This construction prevents the SHG beam from being reflected from the silicon substrate 212 and scattered, and therefore a favorable image can be obtained in the far field for the SHG beam emitted from the nonlinear optical element 215 .
In this embodiment, a resistor 213 a is formed at a portion of the wire connected between the phase control region and the DBR region of the semiconductor laser device. Due to the same principle as in Embodiment 9, by controlling the value R of the resistor 213 a so that the oscillation longitudinal mode orders do not generate mode-hopping, the oscillation wavelength of the laser beam emitted from the semiconductor laser device can be varied continuously. Note here that the value of R preferably is set within a range between 10 −3 Ω·cm and 10 6 Ω·cm.
According to this embodiment, by providing a portion of the wire connected between the phase control region and the DBR region with a function as a resistor and controlling the value of the resistor, the oscillation wavelength of the laser beam emitted from the semiconductor laser device can be controlled with stability.
In addition, since the nonlinear optical element 215 is mounted on the substrate in such a manner that its optical waveguide 210 is located away from the center line M 10 a -M 20 a of the silicon substrate 212 , the width of the wavelength conversion device can be narrowed to 5 mm or less, and therefore a small wavelength conversion device having approximately the same size as the nonlinear optical element 215 can be realized. As a result, the silicon substrate 212 further can be miniaturized, and therefore the wavelength conversion device can be miniaturized and the cost can be reduced.
[Embodiment 12]
FIG. 12 is a plan view of a wavelength conversion device according to this embodiment. On a silicon substrate 212 (2.0 mm in width, 6 mm in length), electrodes 221 , 222 , 223 , 224 , and 225 are formed by patterning, and a DBR laser element 227 (0.3 mm in width, 1.2 mm in length) and a nonlinear optical element 215 (2.8 mm in width, 10 mm in length) are mounted in an integrated manner. Numeral 210 denotes an optical waveguide, and 211 denotes a diffraction grating formed in the optical waveguide 210 . Line 100 is a center line of the optical waveguide 210 . Line M 10 b -M 20 b is a center line of the width direction of the silicon substrate 212 and line M 50 b -M 60 b is a center line of the width direction of the nonlinear optical element 215 . In this way, the construction of the wavelength conversion device in this embodiment is similar to that of the wavelength conversion device according to Embodiment 11, except that the silicon substrate 212 is miniaturized so that a length of a region where the DBR laser element 227 is mounted on the silicon substrate 212 is 3 mm along the longitudinal direction of the silicon substrate 212 , and the nonlinear optical element 215 is mounted on the substrate so that the center line 100 of its optical wavelength 210 is 0.7 mm away from the center line of the silicon substrate 212 . That is, in this embodiment also, the nonlinear optical element 215 is arranged within 3 μm from the DBR laser element 227 so as to securely introduce the laser beam emitted from the DBR laser element 227 . Therefore, their explanations will be omitted.
According to this embodiment, the same effects as in Embodiment 11 can be obtained. In addition, by reducing the length of the silicon substrate 212 , the region where the nonlinear optical element is mounted on the silicon substrate 212 is narrowed. Therefore, distortion generated due to the contact between the nonlinear optical element 215 and the silicon substrate 212 can be reduced, and a conversion efficiency from the laser beam emitted from the DBR laser element 227 into the SHG beam can be improved.
In the above-stated embodiments, the substrate is made of silicon. However, instead of silicon, materials such as SiC or AlN may be used. With these materials, thermal dissipation of the device can be improved, the operational current of the semiconductor laser device can be decreased, and the operational temperature range of the semiconductor laser device can be broadened. Alternatively, resin such as plastic may be used. If using a resin substrate, an electrical wiring pattern can be integrated on the substrate. As a result, a more light-weight, miniaturized, and low-cost wavelength conversion device can be obtained.
In the above-stated embodiments, the nonlinear optical elements are made of LiNbO 3 . Instead, materials such as LiTaO 3 , KTiOPO 4 , and KNbO 3 may be used.
In the above-stated embodiments, DBR laser elements are used as the semiconductor laser device. Instead, multielectrode driven type laser elements such as a multielectrode semiconductor laser device capable of a Fabry-Perot mode oscillation, a multielectrode Distributed Feedback (abbreviated as “DFB”) type laser element, a multielectrode bistable semiconductor laser element, and a pulse laser may be used. With these elements, the time dependency of the output power of the SHG beam can be lessened. Alternatively, instead of the DBR laser element, laser elements whose wavelength can be controlled may be used.
In the above-stated embodiments, the semiconductor laser devices have three regions. However, insofar as the oscillation wavelength of the laser beam emitted therefrom can be controlled adequately, semiconductor laser devices having two regions or four or more regions may be used.
If optical components such as a lens, birefringence material, prism, mirror, and an optical modulator may be integrated as the integrated components, in addition to the semiconductor laser device and the nonlinear optical element, a small wavelength conversion device can be obtained.
Furthermore, the wires connecting components may be integrated on the silicon substrate directly. In the case of the substrate made of silicon, instead of metal, polycrystal silicon, p-type silicon, and n-type silicon can be used as a material of the wire.
The invention may be embodied in other forms without departing from the spirit or essential characteristics thereof. The embodiments disclosed in this application are to be considered in all respects as illustrative and not limiting. 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 wavelength conversion device that converts a wavelength by second harmonic-wave generation and generates a laser beam, includes: a substrate having a plurality of electrodes; a semiconductor laser device mounted on the substrate and electrically connected to the plurality of electrodes; and a nonlinear optical element having an optical waveguide for guiding a laser beam emitted from the semiconductor laser device and for converting a wavelength of the laser beam. Here, the nonlinear optical element is mounted on the substrate so that the optical waveguide in the nonlinear optical element is located away from the center line of the substrate. Thereby, a small wavelength conversion device provided with a semiconductor laser device and a nonlinear optical element, which are mounted on the substrate in an integrated manner, can be obtained, and therefore an optical pickup unit in the optical disk employing this wavelength conversion device can be miniaturized. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a system of building which groups elements of an assembly and reinforces them by means of a network of steel bands.
PRIOR ART
[0002] The present invention refers to a previous invention by the same author <<STRENGTHENING ASSEMBLY ENCLOSED IN CONSTRUCTION>> for a mechanical apparatus which maintains the structural integrity of an assembly even when undergoing changes in volumetry.
[0003] In that first invention flexible bands act perpendicularly, on an assembly of wooden beams, in order to keep the wooden elements tightly together, as the wood dries and diminishes in volume.
[0004] In the present invention, the inventor introduces the notion of a flexible band placed between and parallel to the wooden elements in order to reinforce the assembly.
[0005] In wood, for example, beams of rectangular section are subjected to an effort which creates a compression in the top fibers and tension in the bottom fibers. It is therefore desirable to introduce a flexible band and located it near the bottom fibers, in order to resist the tensile forces created by the bending of the beams through loading.
OBJECTIVES AND ADVANTAGES
[0006] There is always a need in the market and more precisely in the field of architecture and engineering for a system which provides an improved resistance to an assembly of elements.
[0007] A general objective of this invention is to create large construction assemblies from smaller elements by using, first, a network of flexible bands which maintain the elements together and second, a network of flexible bands which reinforce the group of elements at strategic points.
[0008] A more specific objective of this invention is the construction of structural elements by overlapping, regrouping or aligning elements such as wood or other materials resistant to compression, using a device including a pair of components which apply a force, in opposite directions. Between these two components, a steel band is put in tension by the action of two opposite forces applied by the pair of components.
[0009] The present invention will be further understood from the following description with reference to the drawings.
BRIEF DESCRIPTION OF DRAWING FIGURES
[0010] FIG. 1 is a front view of an armed wooden beam.
[0011] FIG. 2 is a front view of an armed concrete beam.
[0012] FIG. 3 is a perspective of a device placed within a wall.
[0013] FIG. 4 is a perspective of a rectangular armed column.
[0014] FIG. 5 is a perspective of an armed slab.
[0015] FIG. 6A is a perspective of an armed I-beam.
[0016] FIG. 6B is a section according to line 3 - 3 of FIG. 6A .
[0017] FIG. 7 is a perspective of an armed I-beam.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] In the following description and in the accompanying drawings, the numeral numbers refer to identical parts in the various Figures.
[0019] FIG. 1 shows a face view of a wooden armed beam 120 comprising seven slats among which bottom slats 124 and top slats 126 . The whole of superimposed slats form a beam 120 . The beam 120 has a top face 132 . The beam has a center 134 . A first end 128 of the beam is supported by a first post 130 , a second end 138 is also supported by a second post 140 . The application of a load in the center 134 would create bending and would create tensile forces in the bottom 136 . In order to prevent failure of the apparatus, a first steel band 142 is installed between a first bottom slat 124 ′ and a second bottom slat 124 ″. A second steel band 144 is positioned between the second bottom slat and a third bottom slat 124 ′″. The two steel bands are tensioned, one by a first winch 150 mounted on a first plate 156 located at the first end 128 pulling the band against the second plate 152 and by a second winch 154 mounted on the second plate 152 at the second end 138 and pulling the second steel band against the first plate 156 . Furthermore, vertical bands 164 are placed at different locations in order to press tightly together the superposed slats, making them act as a whole. A concentrated or uniformly distributed load applied at the center 134 creates bending and tensile forces at the bottom slats. By tightening winches 150 and 154 tension is applied on the two bands, 142 and 144 , along the bottom slats 124 ′, 124 ″, 124 ′″ putting the beams in compression.
[0020] FIG. 2 shows a concrete beam 158 of prior art, armed and supported at one end by a third post 160 and at the other end by a fourth post 170 . The steel rod 162 , incorporated in the concrete, reinforces the concrete where the tensile forces are the greatest when the structure is loaded.
[0021] FIG. 3 shows a group of superimposed beams 20 which include a vertical band 222 positioned within the beam and which includes a blocking at a bottom 224 to which can be added a compression spring; the vertical link includes a ratchet 226 on a higher beam 225 . The assembly includes a pair of flexible bands 228 passing on either side of the vertical band 222 . The pair of flexible bands 228 can be made out of metal, stainless steel, Kevlar or any material having the same characteristics. Seals 244 may be inserted between the beams.
[0022] FIG. 4 illustrates in perspective a column of rectangular section. Flexible bands are placed at strategic places to prevent buckling. A rectangular column 250 of section 252 with a short section 254 , and a long section 256 , formed by three vertical beams, a near beam 258 , a far beam 260 and a middle beam 262 . Between each beam there is a slot 264 where a column band 266 is inserted.
[0023] When a load is applied on a column, buckling can occur at its short section 254 . The installation, of a pair of slots 265 and 265 ′, and a pair of column bands 266 and 266 ′ will prevent the deflection of the column, on either side.
[0024] FIG. 5 shows a wooden armed slab 270 including aligned beams 272 defining a width 274 , a length 276 , a height 278 , a bottom of the slab 280 , a top of the slab 282 , a joint of assembly 286 and a series of slots 284 being used to place longitudinal flexible bands 288 inside the beams to which one adds a means of tension resulting in a compression of the bottom of the wooden slab 270 . The position of the slot 284 is close to the bottom of the wooden slab 270 because it is in this area that the beams are put in tension when loading occurs.
[0025] Transversal holes 290 permit the passage of flexible bands in order to keep the beams tightly together. Sealing joints of assembly 286 are found between the aligned beams.
[0026] FIG. 6A shows another method to arm an I-beam 271 including a top part 273 , a web 275 and a bottom part 277 called flange of the I-beam. At the bottom of the flange 277 an armed longitudinal band 289 with an array teeth or points pointing towards the top 287 and towards the bottom 287 ′ are intended to reinforce the bottom part of the I-beam. The band 289 is inserted between the upper surface of an additional flange 279 and the lower surface of the bottom of the flange 277 of the I-beam.
[0027] FIG. 6B shows the drawing of the section 3 - 3 of the FIG. 6A in which two flanges 277 and 279 are held together by the teeth 287 and 287 ′ which are encrusted in the two flanges. Means of screwing 291 or glue make it possible to fix together the flanges 277 and 279 .
[0028] FIG. 7 shows another method to reinforce an I-beam 271 including a top flange 273 , a web 275 and a bottom flange 277 . At the bottom of the flange 277 a longitudinal band 288 intended to reinforce the bottom of the I-beam is placed on the upper surface of an additional flange 279 intended to be affixed against the lower surface of the bottom of the flange 277 . One integrates to the band 288 a means of tension which will result in the compression of the bottom of the I-beam.
SUMMARY OF THE INVENTION
[0029] The armed structural components can be beams, columns, walls, slabs, made out of composite materials, plastic, wood, concrete and in general any material resistant to compression. The use of flexible bands is intended to reinforce structural elements at their weaker points. The present invention provides a simple and esthetic solution to a technical problem. It is safety oriented, because it is inserted inside the beams, columns and slabs or inside the whole of the assembly in order to be protected from fire, and the natural elements, such as in the case of an apparatus made of solid wood. For example, the device can contain a winch, at the top of a column applying tension to a flexible band and completed by a blocking plate at the bottom of the column. The winch provides a constant force on the band. Using the winch, one manually rolls up the flexible band until one obtains the needed tension.
[0030] A further objective is to provide a flexible structural solution to adapt to the requests of engineers in accordance to the efforts applied in an element of structure. Applications are infinite and inexpensive compared to current structural reinforcing solutions. The present invention maintains the integrity of the structural assembly by maintaining tightly together the beams, and more precisely by reinforcing the assembly in strategic points thus conferring a greater resistance to bending stresses.
In Brief:
[0031] An assembly of structural elements placed one next to the other, which are intended to be subject to efforts resulting in a deflection of the whole assembly. The introduction of bands resistant to traction between and through the structural elements, counterbalance stresses created by the deflection of the assembly.
[0032] The structural elements can be bottom slats 124 laid out under top slats 126 , the bottom slats being subjected to tension efforts, the introduction of a flexible band 142 among the bottom slats, the band including means of tension resulting in a compression of bottom slats thereby reducing the deflection.
[0033] The assembly comprising moreover means of maintaining together the structural elements.
[0034] It is to be clearly understood that the instant description with reference to the annexed drawing is made in an indicative manner and that the preferred embodiments described herein are meant in no way to limit further embodiments realizable within the scope of the invention.
[0035] The matter which is claimed as being inventive and new is limited only by the following claims.
PARTS
[0000]
120 Armed wooden beam
124 Bottom slat
126 Top slat
128 First end
130 First post
132 Top face
134 Center
136 Bottom
138 Second end
140 Second post
142 First band
144 Second band
150 First winch
152 First plate
154 Second winch
156 Second plate
158 Concrete beam
160 Third post
162 Steel rod
164 Vertical band
170 Fourth post
220 Superimposed beams
222 Flexible band
224 Blocking at the bottom
225 Top beam
226 Top ratchet
228 A pair of flexible bands
244 Sealing joint
250 Armed wooden column
252 Rectangular section
254 Small section
256 Long section
258 Near beam
260 Far beam
262 Middle beam
264 Junction
265 Column slot
266 Column band
270 Armed wooden slab
271 I-beam
272 Aligned beams
273 Top flange
274 Width
275 Web
276 Length
277 Bottom flange
278 Height
279 Additional flange
280 Bottom of slab
282 Top of slab
284 Slot in slab
286 Joint of assembly
287 Teeth or points
288 Longitudinal band
289 Armed band
290 Hole
291 Means of screwing
292 Transversal band | In an assembly of structural elements such as beams, columns, walls and floors, one selects materials such as wood which is resistant to compression. Beams placed side by side, or one on top of the other are retained by a network of steel bands installed between and through the beams. Bands with an array of teeth on both sides or winches applying tension to the steel bands, counterbalance the tensile and shear forces created in the assembly through loading and they behave in the same way as steel rods in reinforced concrete. The strategic positioning of the network of bands in the apparatus serves in grouping and reinforcing the structural elements. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to IC cards and, more particularly, to an IC card which stores both a test program for performing a test on the IC card itself (a product test) and an application program for performing various functions required for the use of the IC card.
2. Description of the Related Art
FIG. 6 is a block diagram showing the construction of a conventional type of IC card. As illustrated, a CPU 1 is connected to both a system ROM 3 and an application ROM 4 through a bus 2.
As shown in FIG. 7, the system ROM 3 stores a test program 31 for performing a test on the IC card itself, and the application ROM 4 stores an application program 41 for performing various functions which are required for the use of the IC card. The system ROM 3 further stores a branch routine 32 first for determining whether the test program 31 or the application program 41 should be executed and then for branching to the program to be executed.
Referring back to FIG. 6, an EEPROM 5 for storing variable data, a RAM 6 for temporarily storing data, and an input/output circuit 7 for effecting data communication with external equipment are connected to the bus 2.
As shown in FIG. 8, the system ROM 3, the application ROM 4, the EEPROM 5, the RAM 6 and the input/output circuit 7 are arranged in various address ranges of a memory space. It is therefore possible to easily access a desired area of the respective memories with the same type of instruction.
Also, the system ROM 3, the application ROM 4, the EEPROM 5, the RAM 6 and the input/output circuit 7 are respectively connected to selection circuits 13, 14, 15, 16 and 17 to select the corresponding ones of these memories and the input/output circuit 7 on the basis of the arrangement of the memory space shown in FIG. 8 in accordance with the state of the bus 2.
In FIG. 6, a terminal Pl is a positive power input terminal; P2 is a grounding terminal for a power source; P3 is a reset signal terminal for receiving as its input a reset signal that initializes the CPU 1; P4 is a clock terminal for receiving a clock signal as its input; and P5 is an I/O terminal.
Such an IC card operates in the following manner. When a reset signal is input to the IC card through the reset signal terminal P3, the CPU 1 reads out a routine starting address at which execution of the branch routine 32 is initiated, the routine starting address being stored in advance in the system ROM 3 at a predetermined address thereof. The CPU 1 initiates the execution of the branch routine 32 at this routine starting address. If an instruction for executing the test program 31 is input from external equipment (not shown) to the I/O terminal P5 during the execution of the branch routine 32, the CPU 1 causes the process to proceed from the branch routine 32 to the ensuing test program 31. The test program 31 accesses an arbitrary address to enable a satisfactory product test. The CPU 1 accesses individual addresses in accordance with the test program 31, thereby performing a product test.
On the other hand, if no instruction for executing the test program 31 is input, the CPU 1 reads out a program starting address at which execution of the application program 41 is initiated, the program starting address being stored in advance in the application ROM 4 at a predetermined address thereof. The CPU 1 initiates the execution of the application program 41 at this program starting address.
However, since the system ROM 3 and the application ROM 4 are arranged in a memory space as described previously, when the IC card is being used in its normal memory arrangement, that is, during the execution of the application program 41, the CPU 1 may read out the test program 31 to find a procedure for entering the test program 31. This results in the problem that the CPU 1 may access an arbitrary address by using a function provided in the test program 31, thus providing incorrect access.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide an IC card which can prevent the occurrence of incorrect access to achieve positive operation.
To achieve the above and other objects, in accordance with the present invention, there is provided an IC card comprising a CPU; a first memory for storing a test program; a second memory for storing an application program; a bus connecting the CPU and the first and second memories; detection means for detecting whether the CPU has begun executing the application program; and disconnection means for disconnecting the first memory from the bus when the detection means detects that the CPU has begun executing the application program.
In the present invention, when the detection means detects the fact that the CPU has executed the application program in the second memory, the disconnection means cuts off the connection between the bus and the first memory in which the test program is stored.
The above and other objects, features and advantages of the present invention will become apparent from the following description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing the construction of an IC card according to a first embodiment of the present invention;
FIG. 2A is a diagram showing a normal memory arrangement according to the first embodiment;
FIG. 2B is a diagram showing a memory arrangement for the execution of an application program according to the first embodiment;
FIG. 3 is a circuit diagram showing the essential portion of a second embodiment;
FIG. 4A is a diagram showing a normal memory arrangement according to the second embodiment;
FIG. 4B is a diagram showing a memory arrangement for the execution of an application program according to the second embodiment;
FIG. 5 is a timing chart showing the operation of the second embodiment;
FIG. 6 is a block diagram showing the construction of a conventional type of IC card;
FIG. 7 is a schematic block diagram which serves to illustrate the construction of the system ROM and of the application ROM; and
FIG. 8 is a diagram showing a memory arrangement in the conventional type of IC card.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiments of the present invention will be described below with reference to the accompanying drawings wherein the same constituent elements are indicated by like reference numerals.
FIG. 1 is a block diagram showing the construction of an IC card according to a first embodiment of the present invention. The illustrated IC card includes a CPU 1, and a system ROM 3 as a first memory and an application ROM 4 as a second memory are connected to the CPU 1 through a bus 2. Furthermore, an EEPROM 5 for storing variable data, a RAM 6 for temporarily storing data and an input/output circuit 7 for data communication with external equipment (not shown) are connected to the bus 2.
The system ROM 3 stores a test program for performing a test on the IC card itself, and the application ROM 4 stores an application program for performing various functions which are required for the use of the IC card. The system ROM 3 further stores a branch routine for first determining whether the test program or the application program should be executed and then branching to the program to be executed.
Selection circuits 14, 15, 16 and 17 are connected to the application ROM 4, the EEPROM 5, the RAM 6 and the input/output circuit 7, respectively. The selection circuits 14, 15, 16 and 17 select the corresponding memories 4, 5 and 6 or the input/output circuit 7 according to the state of the bus 2.
A selection circuit 8 as a disconnection means is connected to the system ROM 3, and a detection circuit 9 which serves as a detection means is connected to the selection circuit 8. When the detection circuit 9 detects through the bus 2 that the CPU 1 has read out the program starting address of the application program in the application ROM 4, the detection circuit 9 outputs a system ROM selection inhibit signal to the selection circuit 8. Like the other selection circuits 14 to 17, the selection circuit 8 selects the system ROM 3 on the basis of the state of bus 2 to enable data communication with the bus 2. When the system ROM selection inhibit signal is input from the detection circuit 9 to the selection circuit 8, the selection circuit 8 is inhibited from selecting the system ROM 3 irrespective of the state of the bus 2 and substantially cuts off the connection between the system ROM 3 and the bus 2.
Like the conventional example shown in FIG. 6, the present IC card is also provided with the positive power input terminal P1, the power source grounding terminal P2, the reset signal terminal P3, the clock terminal P4, and the I/0 terminal P5.
The operation of the first embodiment will be described below.
When a reset signal is applied to the input of the reset signal terminal P3, the CPU 1 reads out the routine starting address of the branch routine which is stored at a predetermined address in the system ROM 3, and initiates the execution of the branch routine at the routine starting address.
In the branch routine, the state of the I/O terminal P5 is first checked to determine the presence or absence of an instruction for executing a product test. If the instruction for executing the product test is detected, the test program is executed subsequently to the branch routine. This test program accesses an arbitrary address in order to perform a satisfactory product test. The CPU 1 accesses individual addresses in accordance with the test program and performs the product test.
During this time, the system ROM 3, the application ROM 4, the EEPROM 5, the RAM 6, and the input/output circuit 7 are connected to the bus 2 and are arranged in various address ranges of a memory space as shown in FIG. 2A. The memories 3, 4, 5, 6, and the input/output circuit 7 are selected by the corresponding selection circuits 8, 14, 15, 16, and 17 on the basis of the state of the bus 2.
On the other hand, if the instruction for executing the product test is not input, the CPU 1 reads out the program starting address of the application program which is stored at a predetermined address in the application ROM 4 in order to cause the process to proceed from the branch routine to the application program in the application ROM 4. At this time, the detection circuit 9 detects that CPU 1 has read out the program starting address of the application program, so that the system ROM selection inhibit signal is output from the detection circuit 9 to the selection circuit 8. Thus, the selection circuit 8 is inhibited from selecting the system ROM 3 irrespective of the state of the bus 2. In other words, the connection between the system ROM 3 and the bus 2 is disconnected, i.e., substantially cut off, and, as shown in FIG. 2B, the system ROM 3 is excluded from the memory space.
In such a state, the CPU 1 executes the application program. Accordingly, it becomes impossible to access the test program from the application program in the system ROM 3, whereby incorrect access is prevented.
FIG. 3 is a circuit diagram showing the concrete construction of the detection circuit 9 and the selection circuits 8 and 14 associated with the system ROM 3 and the application ROM 4, respectively. The illustrated circuit includes a flip-flop circuit 18, address code AND circuits 19 to 21, a NAND circuit 22, and inverter circuits 23 to 25. The circuit of FIG. 3 provides control over the selection between the system ROM 3 and the application ROM 4 according to a specified address in the memory space having addresses of four-digit hexidecimal numbers (of 16-bit construction).
FIG. 4A shows a memory arrangement which is normally selected. In the normal memory arrangement, the application ROM 4 is arranged in an area defined by addresses 4000 to 7FFF and the system ROM 3 is arranged in an area defined by addresses C000 to FFFF. The program starting address of the application program in the application ROM 4 is 5000, and an initial instruction A9 in the application program is stored at address 5000. Also, the program starting address 5000 is stored at addresses 7FFE and 7FFF in the application ROM 4. Of these addresses at which is stored the program starting address 5000 of the application program, the lower address 7FFE is stored at addresses E001 and E002 in the system ROM 3. A jump instruction 6C stored at address E000 which is contiguous to the address E001 in the downward direction enables the process to jump to the program stored in addresses 7FFE and 7FFF starting address 5000 of the application program.
The operation of the circuit shown in FIG. 3 will be described below with reference to the timing chart of FIG. 5.
When the power source is switched on and a reset signal is input to the terminal R D of the flip-flop circuit 18, the flip-flop circuit 18 is reset and the system ROM selection inhibit signal goes to a low level. Therefore, a high-level signal is output from the inverter circuit 25 to the AND circuit 20. Thus, the memory arrangement such as that shown in FIG. 4A is formed.
If an arbitrary address is specified from among addresses C000 to FFFF which define the area of the system ROM 3, a high-level system ROM select signal is input to the system ROM 3 through the AND circuits 19 and 20 since the two high-order bits AD14 and AD15 of each 16-bit address which contains AD0 (the lowest order bit) to AD15 (the highest order bit) are necessarily at the high levels. Thus, the system ROM 3 is selected.
On the other hand, if an arbitrary address from addresses 4000 to 7FFF which defines the area of the application ROM 4 is specified, a high-level application ROM select signal is input to the application ROM 4 through the AND circuits 19, 21 and the inverter circuit 24 since the two high order bits AD14 and AD15 of each address in this area are necessarily at the high level and the low level, respectively. Thus, the application ROM 4 is selected.
In the branch routine stored in the system ROM 3, branching to the application program in the application ROM 4 is effected as follows. First, the jump instruction 6C at address E000 is read, then address 7FFE stored at addresses E001 and E002 is read in accordance with the instruction 6C, and then program starting address 5000 of the application program which is stored at address 7FFE and the following address 7FFF is read out.
At time t 1 at which the program starting address 5000 of the application ROM 4 which is stored in the area of the application ROM 4 is read, a low-level signal is, as shown in FIG. 3, input from the NAND circuit 22 to the flip-flop circuit 18 since both the high-level application ROM select signal is input to the application ROM 4 and the lowest order bit AD0 that designates address 5000 is at the high level. Thus, the system ROM selection inhibit signal output from the flip-flop circuit 18 is inverted to a high level, and subsequently the system ROM selection inhibit signal is maintained at the high level until a reset signal is again input to the flip-flop circuit 18. Accordingly, the low-level signal is input through the inverter circuit 25 to the AND circuit 20 connected to the system ROM 3, and the system ROM select signal is maintained at the low level irrespective of the state of the bus 2, particularly the levels of the bits AD14 and AD15, whereby it becomes impossible to select the system ROM 3.
In other words, the connection between the system ROM 3 and the bus 2 is cut off so that the memory arrangement which excludes the system ROM 3 as shown in FIG. 4B is formed.
It is to be noted that the first and second embodiments shown in FIGS. 1 to 5 are intended for the purpose of illustration only, and the present invention is not limited to such embodiments. | An IC card has a CPU, a first memory for storing a test program, a second memory for storing an application progam, a bus connecting the CPU and the first and second memories. A detection circuit for detecting whether the CPU has began executing the application program stored in the second memory, and a disconnection circuit for disconnecting the first memory from the bus when the detection circuit detects that the CPU has begun executing the application program. The above-described arrangement makes it impossible to access the test program in the system ROM from the application program thereby preventing the occurrence of incorrect access. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to communication methods for networks utilizing relay nodes, and particularly to a bandwidth efficient cooperative two-way amplify-and-forward relaying method that allows users in a secondary network to utilize a relay node in the primary users' network while minimizing co-channel interference.
[0003] 2. Description of the Related Art
[0004] Bi-directional relay communications are considered as a promising transmission scheme to increase network throughput and to improve spectral efficiency, especially with half-duplex communication models. The operations in bi-directional relaying communications can be divided into two phases, namely, a transmission phase, in which the two sources transmit their data, and a relaying phase, in which the relay node relays the previously received data.
[0005] The two well-known relaying protocols, namely, amplify-and-forward (AF) and decode-and-forward (DF), are typically employed, resulting in two categories of bi-directional communications known as two-phase and three-phase two-way relaying schemes. In the two phase scheme, the AF relaying protocol is applied, where two symbols are transmitted in two phases (one transmission and one relaying), while the DF relaying protocol is applied in a three-phase scheme, where 2 symbols are transmitted in three phases (two transmission and one relaying). Although the two-phase scheme achieves a relatively better spectral efficiency than the three-phase scheme, the three-phase scheme outperforms the two-phase scheme.
[0006] The performance of the two-way relaying schemes with various transmission protocols and network coding schemes has been investigated. However, none of the proposed amplify-and-forward relaying protocols have proven entirely satisfactory so that it has not been possible to take maximum advantage of the bandwidth efficiency of the amplify-and-forward relay protocol.
[0007] Thus, a bandwidth efficient cooperative two-way amplify-and-forward relaying solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
[0008] The bandwidth efficient cooperative two-way amplify-and-forward relaying method allows users in a secondary network to utilize a relay node in the primary users' network while minimizing co-channel interference. In the method, two primary user network sources communicate through a primary user network relay node. A secondary user network source and a secondary user destination agree to act as relays for the primary network sources, all of the above using amplify-and-forward protocol. In return, the primary network relay node allows the secondary user source to communicate through the primary network relay node with the secondary user destination using decode-and-forward protocol. Five symbols, including four primary user symbols and one secondary user symbol, are transmitted in four time slots for a bandwidth efficiency of 1.25. The primary network relay and the secondary users relay transmissions have their power allocated to minimize symbol error rate and maximize sum rate.
[0009] These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1A is a block diagram showing the entity relations during the transmission phase in a first time slot in a bandwidth efficient cooperative two-way amplify-and-forward relaying method according to the present invention.
[0011] FIG. 1B is a block diagram showing the entity relations during the transmission phase in a second time slot in a bandwidth efficient cooperative two-way amplify-and-forward relaying method according to the present invention.
[0012] FIG. 2A is a block diagram showing the entity relations during the relaying phase in a third time slot in a bandwidth efficient cooperative two-way amplify-and-forward relaying method according to the present invention.
[0013] FIG. 2B is a block diagram showing the entity relations during the relaying phase in a fourth time slot in a bandwidth efficient cooperative two-way amplify-and-forward relaying method according to the present invention.
[0014] FIG. 3 is a plot comparing the bandwidth efficient cooperative two-way amplify-and-forward relaying method according to the present invention and conventional relaying schemes.
[0015] Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] The bandwidth efficient cooperative two-way amplify-and-forward relaying has a primary user (PU) network that includes two PU sources that are communicating with each other via a single relay. On the other end, a secondary user (SU) source transmits its data to a SU destination via the same PU relay node. The PU network considers the SU network pairs (i.e., source and destination) as two additional relay nodes which help the original PU relay node in improving the PU network performance. As a reward for its cooperation, the PU network allows the SU network to communicate simultaneously via the PU relay node by applying decode-and-forward (DF) protocol. The proposed system transmits four PU symbols and one SU symbol in four time slots, which achieves a bandwidth efficiency of 1:25. Two power allocation optimization problems were formulated; one to minimize the average symbol error rate of both primary and secondary systems, while the other problem is to maximize the total achievable sum rate. A Lagrangian multiplier method is used to find the optimal solutions for both problems under the constraint of maximum allowable power budget.
[0017] The proposed relaying scheme considers multiuser joint detection at relay node and is based on a cooperative cognitive system between a PU network and a SU network. Further, there are several assumptions, such as that there is no direct link between sources and destinations, multiuser maximum likelihood detection, and that the SU pairs source and destination via the PU relay node. The SU network serves as relay nodes the PU network to mitigate its interference and improve system performance. A complete cooperative PU network consists of one PU source, one PU relay and one PU destination. The proposed work consider the SU network pairs (i.e., source and destination) as two extra relay nodes to improve PU network performance. Finally, the SU source communicates with its destination via the cooperation of the PU relay node following the well-known DF protocol while the PU network deals with SU transmission as an interference signal.
[0018] The operation of the proposed scheme that enables the transmission of four PU symbols and one SU symbol in four time slots is presented in FIGS. 1A, 1B, 2A, and 2B respectively. The channel gain between X and R is denoted by h XR , and the channel gains between X and A and B are denoted by h XA and h XB , respectively, with an average of v X 2 . Similarly, the channel gains between Y and R, and A and B, are denoted by h YR , h YA and h YB , respectively with an average of v Y 2 . The channel gain between A and R, are h AR with average channel gain v A 2 . Finally, the channel gain between R and B is h RB with an average of v R 2 .
[0019] For notational simplicity, all the channels are assumed to be independent and identically distributed (i.i.d) flat Rayleigh fading channels. For PU transmission, AF protocol is applied by the three relays since it is relatively less complex and relatively more flexible in handling interference than DF protocol. The operation of the proposed scheme can be divided into two phases. Namely, the transmission phase and the relaying phase.
[0020] In the first time slot shown in FIG. 1A , the PU sources X and Y transmit their modulated symbols denoted by x 1 and y 1 with transmission powers of P X and P Y , respectively. At the same time, SU source A transmits its data a 1 with power P A which interferes with PU data at R. Since there is no direct link between the SU network pairs A and B, the SU receiver B receives the PU transmission with no interference. Then, the received signals at R and B during the first time slot are given by:
[0000] z R (1) =√{square root over ( P X )} h XR x 1 +√{square root over ( P Y )} h YR y 1 +√{square root over ( P A )} h AR a 1 +w R (1) (1)
[0000] z B (1) =√{square root over ( P X )} h XB x 1 +√{square root over ( P Y )} h YB y 1 +w B (1) , (2)
[0000] where w R and w B are AWGN samples with zero-mean and variance σ 2 .
[0021] In the second time slot shown in FIG. 1B , PU sources X and Y transmit their second PU symbols x 2 and y 2 with transmission powers of PX and PY, respectively to A and B. Simultaneously, the relay R jointly decodes the previous received SU data symbol â 1 and transmits it to the SU receiver B with a transmission power P R . The received signals at A and B during the second time slot are given by:
[0000] z A (2) =√{square root over ( P X )} h XA x 2 +√{square root over ( P Y )} h YA y 2 +√{square root over ( P R )} h RA â 1 +w A (2) (3)
[0000] z B (2) =√{square root over ( P X )} h XB x 2 +√{square root over ( P Y )} h YB y 2 +√{square root over ( P R )} h RB â 1 +w B (2) , (4)
[0000] where w A and w B are AWGN samples with zero-mean and variance σ 2 . By the end of transmission phase, the SU transmission is completed. The SU receiver B decodes the transmitted symbol â 1 from R, which is denoted by 1 .
[0022] During the third time slot shown in FIG. 2A , PU and SU sources are idle while R transmits the received signal after trying to remove the interfered SU data a 1 by subtracting the decoded SU symbol at R (i.e., â 1 ) from the received signal z R (1) . On the other hand, the SU receiver B decodes the interfered SU data during the second time slot and applies AF protocol to the remaining signal. Under the assumption of knowing CSI by all relay nodes and destinations, the received signals at X and Y during the third time slot are given by:
[0000] z X (3) =h RX β R ( z R (1) −√{square root over ( P A )} h AR â 1 )+ h BX β B 2 ( z B (2) −√{square root over ( P R )} h RB 1 .)+ w X (3) (5)
[0000] z Y (3) =h RY β R ( z R (1) −√{square root over ( P A )} h AR â 1 )+ h BY β B 2 ( z B (2) −√{square root over ( P R )} h RB 1 .)+ w Y (3) , (6)
[0000] where w X and w Y are AWGN samples with zero-mean and variance σ 2 . The normalized amplification coefficient at R is given by
[0000]
β
R
2
=
λ
R
z
R
(
1
)
.
Similarly,
[0023]
β
B
2
2
=
λ
B
2
z
B
(
2
)
.
[0024] During the fourth time slot shown in FIG. 2B , PU sources and relay nodes are idle while the SU nodes A and B relay the previously received PU data. The SU source A performs self-interference cancellation for its own data a 1 from its received signal during second time slot, i.e., Z A (2) , then applies AF protocol to the resultant signal before re-transmitting it to both PU destinations X and Y. On the other hand, the SU destination B applies AF protocol to the previously received signal during first time slot, i.e., Z B (2) , before re-transmitting to both PU destinations X and Y. The received signals at both PU destinations X and Y during the fourth time slot are given by:
[0000] z X (4) =h BX β B 1 z B (1) +h AX β A ( z A (2) −√{square root over ( P R )} h RA a 1 )+ w X (4) (7)
[0000] z Y (4) =h BY β B 1 z B (1) +h AY β A ( z A (2) −√{square root over ( P R )} h RA a 1 +w Y (4) , (8)
[0000] where w X and w Y are AWGN samples with zero-mean and variance σ 2 . The normalized amplification coefficient at A is given by
[0000]
β
A
2
=
λ
A
z
A
(
2
)
.
Similarly,
[0025]
β
B
1
2
=
λ
B
1
z
B
(
1
)
.
[0026] After the completion of the proposed system phases, the PU nodes apply self-interference cancellation on their received signals to remove their own data before the decoding process. Then, the received signals at both X and Y during the third time slot after self-interference cancellation are given by:
[0000] {tilde over (z)} X (3) =z X (3) −√{square root over ( P X )} h XR x 1 −√{square root over ( P X )} h XB x 2 (9)
[0000] {tilde over (z)} Y (3) =z Y (3) −√{square root over ( P Y )} h YR y 1 −√{square root over ( P Y )} h YB y 2 . (10)
[0027] Similarly, the received signals at both X and Y during the fourth time slot after self-interference cancellation are given by:
[0000] {tilde over (z)} X (4) =z X (4) −√{square root over ( P X )} h XB x 1 −√{square root over ( P X )} h XA x 2 (11)
[0000] {tilde over (z)} Y (4) =z Y (4) −√{square root over ( P Y )} h YB y 1 −√{square root over ( P Y )} h YA y 2 . (12)
[0028] From the previous equations and the presence of two PU destinations in this model, the matrix model for the proposed system at PU node X can be written as:
[0000] {tilde over (z)} X =H X y+{tilde over (w)} X , (13)
[0000] where {tilde over (z)} X =[{tilde over (z)} X (3) {tilde over (z)} X (4) ] T , y=[y 1 y 2 ] T , the channel matrix H X is given by:
[0000]
H
X
=
[
β
R
h
RX
h
RY
β
B
2
h
BX
h
YB
β
B
1
h
BX
h
YB
β
A
h
AX
h
YA
]
,
(
14
)
[0000] and the noise vector at X is given by:
[0000]
w
~
X
=
[
β
R
h
RX
(
P
A
h
AR
(
a
1
-
a
^
1
)
+
w
R
(
1
)
)
+
β
B
2
h
BX
(
P
R
h
RB
(
a
^
1
-
a
^
^
1
)
+
w
B
(
2
)
)
+
w
X
(
3
)
β
B
1
h
BX
w
B
(
1
)
+
β
A
h
AX
(
P
R
h
RA
(
a
^
1
-
a
1
)
+
w
A
(
2
)
)
+
w
X
(
4
)
]
.
(
15
)
[0029] Similarly, the matrix model for the proposed system at PU node Y can be written as:
[0000] {tilde over (z)} Y =H Y x+{tilde over (w)} Y , (16)
[0000] where {tilde over (z)} Y =[{tilde over (z)} Y (3) {tilde over (z)} Y (4) ] T , y=[x 1 x 2 ] T , the channel matrix H Y is given by:
[0000]
H
Y
=
[
β
R
h
RY
h
XR
β
B
2
h
BY
h
XB
β
B
1
h
BY
h
XB
β
A
h
AY
h
XA
]
,
(
17
)
[0000] and the noise vector at Y is given by:
[0000]
w
~
Y
=
[
β
R
h
RY
(
P
A
h
AR
(
a
1
-
a
^
1
)
+
w
R
(
1
)
)
+
β
B
2
h
BY
(
P
R
h
RB
(
a
^
1
-
a
^
^
1
)
+
w
B
(
2
)
)
+
w
Y
(
3
)
β
B
1
h
BY
w
B
(
1
)
+
β
A
h
AY
(
P
R
h
RA
(
a
^
1
-
a
1
)
+
w
A
(
2
)
)
+
w
Y
(
4
)
]
.
(
18
)
[0030] Note that, for a relay selection scheme, the best relay is selected with maximum channel gains for both PU sources (i.e., X and Y). Then, all the previous equations in relaying phase are valid with setting the unselected relay channel coefficients to zero.
[0031] A power allocation optimization problem was formulated to minimize the sum SER of both PU and SU networks of the proposed system by controlling the SU transmission power (i.e., P A and P R ) and the three relays amplifying factors (i.e., λ A , λ R , λ B 1 , and λ B 2 ). The goal is to find the values of those parameters that minimize the overall SER. Then, an optimization problem has been formulated in which the target function can be minimizing the total sum SER of the PU and SU networks. Such that:
[0000]
minimize
SER
PU
+
SER
SU
subject
to
∑
i
P
i
+
∑
j
λ
j
≤
P
_
total
,
(
19
)
[0000] where i=A and R, while j=A, R, B1 and B2. Lagrangian multipliers method with the power constraint in (19) is used. The Lagrangian function ∫(.) can be expressed as:
[0000] ∫( P i ,λ i )= SER PU +SER SU +Λ 1 (Σ i P i +Σ j λ j − P total ) (20)
[0000] where Λ 1 denotes the Lagrangian multipliers.
[0032] A power allocation optimization problem for maximizing the average achievable sum rate of the proposed system was also formulated. The average achievable sum rate is a function of SU transmission power (i.e., P A and P R ) and the three relays amplifying factors (i.e., λA, λR, λ B 1 , and λ B 2 ). The goal is to find the optimal values which maximize the average achievable sum rate. Then, an optimization problem has been formulated such that:
[0000]
maximize
PU
+
SU
subject
to
∑
i
P
i
+
∑
j
λ
j
≤
P
_
total
.
(
21
)
[0033] Following the same steps in solving equation (19), the optimal solution for rate maximization can be obtained.
[0034] Referring to FIG. 3 , numerical examples are presented to verify the performance of proposed scheme. Since the proposed scheme transmits 5 data symbols in 4 time slots with bandwidth efficiency equal to 1:25. The proposed system performance was compared with the conventional two-way AF relaying scheme. For a fair comparison, the total power budget is set to be the same. A SER performance comparison between the proposed system and the conventional TWR is presented in FIG. 3 . Results show that the conventional TWR model achieves better SER performance compared to the proposed work. As the SNR goes higher, the proposed system in both cases of spatial multiplexing and relay selection outperforms the conventional TWR scheme, which encourages the PU system to cooperate with the SU network.
[0035] It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | The bandwidth efficient cooperative two-way amplify-and-forward relaying method allows users in a secondary network to utilize a relay node in the primary users' network while minimizing co-channel interference. In the method, two primary user network sources communicate through a primary user network relay node. A secondary user network source and a secondary user destination agree to act as relays for the primary network sources, all of the above using amplify-and-forward protocol. In return, the primary network relay node allows the secondary user source to communicate through the primary network relay node with the secondary user destination using decode-and-forward protocol. Five symbols, including four primary user symbols and one secondary user symbol, are transmitted in four time slots for a bandwidth efficiency of 1.25. The primary network relay and the secondary users relay transmissions have their power allocated to minimize symbol error rate and maximize sum rate. | 7 |
DESCRIPTION
BACKGROUND OF THE INVENTION
This invention relates to the field of presser bars for sewing machines and, in particular, to a simplified presser bar guide structure that substantially eliminates the necessity of presser foot pressure adjustment by the sewing machine operator. The invention is especially related to a presser bar bushing that need not be rigidly attached to the head of the machine and is, therefore, easy to install. The presser bar bushing of this invention is also simple to manufacture.
Various arrangements have been proposed heretofore to use tension springs to furnish the force necessary for a sewing machine presser bar. One such arrangement is shown in the copending application of James A. Transue and William Weisz, Ser. No. 81,404, filed Oct. 3, 1979 and assigned to the assignee of the present case. In that application, a tension spring is screwed onto threaded, hollow sleeves extending from members spaced along the presser bar. The force of the spring is directed along the axis of the presser bar to avoid pulling the presser bar to one side, which would produce an effect known as stick slip. The member nearer the presser foot end of the presser bar is held down by an adjustment structure that includes a yoke that prevents the member from rotating. The yoke is attached to adjustment means to adjust the pressure applied from the tension spring via the presser bar and the presser foot to work being sewn. The member onto which the other end of the tension spring is screwed is rigidly attached to the opposite end of the presser bar from the presser foot and is connected to a presser foot lever pivotally mounted on a rigid part of the machine and having a cam through which pressure is applied to lift the pressure bar and the presser foot away from the material being sewn to allow that material to be moved freely.
The apparatus to which the tension spring is connected in the Transue et al application is relatively complex to manufacture, assemble and operate. The basic concept of applying pressure axially by way of a tension spring screwed onto a threaded sleeve attached to the presser bar and another threaded sleeve attached to the machine to avoid stick slip operates quite satisfactorily, but its specific embodiment in the Transue et al application involves complex machining and assembly operations. In addition, it makes available to the sewing machine operator a presser bar pressure adjustment that we have since determined to be unnecessary and even undesirable.
The use of an extension spring to apply downward force to a presser bar to bias it against the work in a sewing machine has been suggested by Rodman in U.S. Pat. No. 823,442, by Feigel in U.S. Pat. No. 1,749,529, by Niekrawietz in U.S. Pat. No. 3,282,237, by Herr in U.S. Pat. No. 3,611,963, by Giesselmann et al in U.S. Pat. No. 4,044,701, and by Takikawa in Japanese disclosed patent application 53-141755, published Dec. 9, 1978. However, in each of those documents, the force of the extension spring was not applied directly along the axis of the presser bar but was applied to one side of the axis. This not only produced a mechanical moment resulting in mechanical hysteresis, but also made it impossible to achieve the simplified arrangement of screwing the spring onto threaded members concentric with the presser bar. A further spring adjustment mechanism was proposed by Chawick in U.S. Pat. No. 1,221,138 in which a spring was screwed onto the threaded end of a bolt rotatably supported in a sewing machine head. The other end of the spring was attached to a feeding bar to apply pressure to it, entirely separate from the presser foot.
OBJECTS AND SUMMARY OF THE INVENTION
It is a main object of this invention to reduce the cost of sewing machine manufacture without reducing reliability of operation.
A related object is to provide a simplified presser bar support mechanism with a substantially reduced number of parts, each easy to manufacture and to assemble with the other parts, in particular by avoiding the necessity of attaching the presser bar guide bushing rigidly to the head of the machine.
Another object is to simplify operation of a sewing machine by permitting only limited adjustment of presser foot pressure to be made, normally only during manufacture of the machine, if at all.
Further objects will become apparent from the following specification, together with the drawings.
In accordance with the present invention, a cylindrical presser bar is guided for longitudinal movement in a hollow, cylindrical bushing having an external surface that is smooth and round along at least part of its cylindrical length. The cylindrical support member includes internal journal means near its opposite ends to guide the longitudinal movement of the presser bar. A smooth cylindrical part is held in a relatively close-fitting round channel in the head of a sewing machine and is prevented from being forced too far into the head by a shoulder that bears against the outer surface of the head surrounding the channel. At the end of the cylindrical part inside the head is a threaded tubular portion of suitable configuration onto which one end of a helical tension spring is screwed.
The tension spring pulls the shoulder against the head, which keeps the bushing from falling out but avoids the necessity of using a set screw or any other means to hold the bushing rigidly in place. This reduces the cost of the parts associated with applying pressure to the presser bar by 30 percent or even more. The spring coaxially surrounds the part of the presser bar within the head of the machine and is screwed onto a hollow, tubular, externally threaded portion of another member rigidly attached to the presser bar at or near the end of the presser bar within the sewing machine head. This latter member has a surface against which a presser bar lever cam surface can be forced to raise the presser bar against tensile force provided by the spring. The latter threaded member also has a shoulder at the end of its threaded portion, and one end of the spring is screwed against this shoulder to set the location of that end of the spring. The other end of the spring is screwed against the inner surface of the head immediately adjacent the threaded tubular portion of the presser bar bushing.
Rigid attachment of the bushing to the head of the machine is not only unnecessary but undesirable. The characteristics of the spring are calculated so that, normally, it is screwed against the shoulder on the member at one end and against the inner surface of the head at the other end. Screwing the spring against fixed stops at each end eliminates the necessity of accurately gaging the position of the spring during manufacture of the machine. If necessary, the tension can be adjusted, but only as a factory adjustment during assembly of the machine. At that time, limited adjustment can be made by rotating the end of the bushing that extends through the channel in the head to reduce the tension.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an end view of a sewing machine incorporating the presser bar arrangement of the present invention and with parts of the structure broken away to show some of the internal components;
FIG. 2 is an enlarged cross-sectional view of a fragment of the presser bar arrangement in FIG. 1 to illustrate the attachment of one end of the tension spring; and
FIG. 3 is an enlarged cross-sectional view of a fragment of a modified embodiment of the head of the sewing machine in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The machine in FIG. 1 includes a bed 11 with a standard 12 extending upwardly therefrom. At the upper end of the standard is an arm, the surfaces 13-15 of which appear only as edges in FIG. 1. At the end of the arm, and in front of the upper end of the standard 12, as depicted in FIG. 1, is a head 16 of the sewing machine. A needle bar 17 is mounted in the head 16 in the customary way and has a clamp 18 at its lower end to hold a needle 19.
This invention is particularly concerned with apparatus associated with a presser bar 21. Such apparatus includes a hollow cylinder, or bushing, 22 in which the cylindrical presser bar 21 is journalled for longitudinal movement. The lower end of the presser bar 21 is conventionally shaped so that a holder 23 of a presser foot 24 may be attached to it by means of a knurled screw 26. The bushing 22 has a shoulder 27 that abuts against the lower surface 28 of the head 16 when the bushing is properly in place. Above the shoulder 27 is a portion 29 of the cylinder 22 that has a smaller diameter than the portion 31 below the shoulder. The portion 29 is smoothly rounded and fits snugly into a round hole, or channel, 32 in the lower part of the head 16.
The tubular end of the portion 29 constitutes a hollow sleeve 30 that extends into the hollow space within the head 16 and is threaded to receive one end of a tension spring 33. The spring 33 is screwed onto the threaded end 30 until it engages an abutment surface portion 34 of the inner surface of the head 16 immediately adjacent the channel 32. The other end of the spring 33 is screwed onto another hollow, threaded sleeve 36 that can be identical to the sleeve 30 at the end of the portion 29 and is integral with an attachment member 37 rigidly attached to the upper end of the needle bar 21 by means of a set screw 38. In this embodiment, the member 37 has a downwardly facing abutment surface 40 against which the spring 33 is screwed, and a downwardly extending section 39 with a lowermost surface 41 located where it can be engaged by a cam surface 42 of a presser bar lifting lever 43. The lever 43 is pivotally mounted on a shoulder screw 44 in the head 16.
The sewing machine in FIG. 1 is shown with the presser foot 24 down against material 46 that is to be sewn. This material is engaged from below by a feed dog 47 that extends up through a throat plate 48 in the bed 11.
FIG. 2 shows the presser bar 21 and the presser foot 24 in their respective elevated positions to free the material 46 so that it can be moved easily. In order to raise the presser bar 21, the lever 43 is shown pivoted clockwise from the position it occupies in FIG. 1. The cam surface 42 has pushed the member 39 upwardly, and a flat surface 49 has come into position to receive the surface 41 of the member 39 substantially directly in line with the screw 44 so that the lever 43 is stable in this position and can hold the presser bar 21 and presser foot 24 elevated without the necessity of the operator's having to hold the lever 43 up.
Part of the bushing 22 is shown broken away in FIG. 2 to illustrate that, over most of its length, its inner surface 51 has a larger diameter than the external cylindrical surface of the presser bar 21. The bushing 22 is formed with short regions 52 and 53 of inner diameter just enough larger than the outer diameter of the presser bar 21 to allow a smooth sliding fit between the presser bar and these regions of reduced diameter, which serve as journals for the presser bar.
The spring 33 is shown extended in FIG. 2, as is required to provide the force that urges the presser bar 21 downwardly in opposition to the restraint provided by the presser bar lever 43.
In order to assemble the presser bar mechanism, the upper end of the spring 33 may be screwed onto the sleeve 36 until it comes into contact with the surface 40. Next, the member 37 is fitted onto the upper end of the presser bar 21, which extends loosely through the channel 32, and is attached to the presser bar by tightening the set screw 38. Thereafter, the bushing 22 is aligned with the channel 32 and the lower end of the presser bar 21 and is fed upwardly to engage the lower end of the spring 33. Then the bushing 22 is rotated to screw the threaded sleeve 30 into the spring 33 until the lowermost end of the spring abuts against the surface 34. Under normal circumstances, this is all that is necessary to assemble these parts, but if, in testing the machine following complete assembly, it appears that a modification in the presser foot pressure should be made, the bushing 22 may be backed off slightly from the position in which the ends of the spring 33 are in contact with the surfaces 34 and 40. The characteristics of the spring are so calculated that the only such adjustment likely to be required is one that would necessitate this backing off; the bushing 22 cannot be turned in the direction to cause the spring 33 to be more fully screwed onto the sleeve 30 or the sleeve 36 because such further engagement of the spring is prevented by contact with the surfaces 34 and 40.
FIG. 3 is an enlarged cross-sectional view of a small part of a modified presser bar support structure. The modified structure includes a bushing 54 that has a uniform diameter over most of its length, instead of having an upper portion of one diameter and a lower portion of a large diameter with a shoulder at the intersection of the two portions. In FIG. 3, the bushing 54 has a groove 56 into which a split ring 57 is fitted, and the upper surface 58 of the split ring is the equivalent of the shoulder 27 in FIG. 1. Above the level of the shoulder surface 58, the bushing 54 is virtually identical with the upper portion 29 in the embodiment of FIGS. 1 and 2 and the component parts of this upper portion are identified by the same reference numerals as are used in the embodiment in FIGS. 1 and 2.
The enlarged cross-sectional view in FIG. 3 permits the configuration of the thread 59 on the sleeve 30 to be shown. The thread has a semi-circular cross-section that substantially matches the shape of the wire of which the spring 33 is made. This is also the same thread configuration formed on the sleeve 36 in the embodiment of FIGS. 1 and 2. The root diameter of the thread 59 is such that there is a small interference between the spring 33 and the surface that defines the thread 59. This interference does not pose a problem when the sleeve 30 is being screwed into the spring, because any engagement between the spring and the thread 59 tends to unwind the spring, i.e., to enlarge its inner diameter, which makes it easier to screw the threaded sleeve into the spring. However, it is much more difficult to unscrew the sleeve, because any friction between the surface of the thread 59 and the surface of the spring 33 tends to wind the spring more tightly, i.e., to reduce its inner diameter, which causes the spring to grip the sleeve more firmly.
FIG. 3 shows more clearly than does FIGS. 1 or 2 the extent of which the spring 33 is screwed onto the sleeve 30. As may be seen in FIG. 3, the spring 33 is screwed far enough onto the sleeve 30 to cause the tip end of the spring to come into contact with the surface 34. This grips the portion of the head 16 immediately between the end of the spring 33 and the shoulder surface 58, which stabilizes the position of the bushing 54 in the channel 32. While the channel 32 fits snuggly around the portion 29, the two components are not bound together as they would be by an interference fit. There is still a minute amount of looseness that could show up as a minute pivoting about some undefined axis perpendicular to the coincident axes of the presser bar 21, the bushing 54, and the channel 32. By tightening the sleeve 30 into the spring 33, the end of the spring and the shoulder surface 58 are forced against opposite surfaces of the head 16, thereby stabilizing to an even greater degree the physical relationship between the portion 29 and the head 16. | A hollow bushing (22 or 54) that guides a presser bar (21) to move in a longitudinal direction is threaded at one end (29 and 30). The outer surface of that end is round and, below the thread (59), fits closely but rotatably in a channel (32) in the head (16) of a sewing machine. The bushing is not fixedly held in place in the channel (32). Instead, a tension spring (33) screwed onto the threaded end and onto a threaded member (37) attached to the end of the presser bar (21) within the head (16) pulls the presser bar downwardly so that its foot (24) normally presses against the work (46) and simultaneously pulls the bushing (22 or 54) toward the head (16). A shoulder surface (27 or 58) at a certain location on the bushing (22 or 54) acts as a stop to limit the extent that the cylinder can be drawn into the head. The spring (33) is fully screwed onto the threaded sleeves (30 and 36) until the ends of the spring butt against surfaces (34 and 40), eliminating operator-adjusted presser foot pressure and simiplying the presser foot pressure mechanism. | 3 |
RELATED APPLICATION
The present disclosure relates to subject matter contained in priority Korean Application No. 10-2008-0094958, filed on Sep. 26, 2008 and U.S. Patent Application No. 61/100,572, filed on Sep. 26, 2008, which are herein expressly incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid storage container and a clothes dryer having the same, and particularly, to a liquid storage container capable of storing liquid material such as fragrant material sprayed into a drum of a clothes dryer, and the clothes dryer having the same.
2. Background of the Invention
In general, a clothes dryer indicates an apparatus for drying laundry having completely undergone a dehydration process after a washing process, by introducing the laundry into a drum of the clothes dryer, and by evaporating moisture inside the laundry by supplying hot blast into the drum.
The clothes dryer comprises a drum disposed in the clothes dryer and into which laundry is introduced, a driving motor for driving the drum, a blow fan for blowing air into the drum, and a heating means for heating the air introduced into the drum.
The heating means may use high-temperature electric resistance heat generated by using an electric resistance, or combustion heat generated by combusting gas.
Air having been discharged from the drum contains moisture of the laundry inside the drum, thereby changing into high-temperature humid air. According to a method for processing the high-temperature humid air, the clothes drier may be classified. More concretely, the clothes drier is classified into a condensation type clothes dryer for condensing moisture inside high-temperature humid air by heat-exchanging the high-temperature humid air with external air through circulation in the clothes dryer without discharging the high-temperature humid air out of the clothes dryer, and an exhaustion type clothes dryer for directly discharging high-temperature humid air having passed through the drum to the outside.
When drawing the laundry having completely undergone a washing process out of a washing machine so as to introduce the laundry into the clothes dryer, a user may have discomfort in smelling odor of used washing water and detergent, or odor of the laundry prior to the washing process. Accordingly, it was required to supply fresh feeling of the laundry to the user by removing the odor of the laundry. For this end, there have been efforts to supply functional material such as fragrant material into the drum. The fragrant material to be stored in a storage container has to be supplied with an appropriate amount corresponding to a usage amount. Accordingly, there has been required a means to allow the user to conveniently check a remaining amount of the fragrant material inside the storage container.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide a liquid storage container capable of storing liquid material therein and easily checking a remaining amount of the liquid material.
Another object of the present invention is to provide a clothes dryer having a liquid storage container capable of easily checking a remaining amount of liquid material.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a liquid storage container, comprising: a reservoir installed at a clothes dryer, and configured to store liquid therein; a floating member floating on the liquid, and disposed on the reservoir with a rotation angle variable according to level change of the liquid inside the reservoir; and display means configured to display information corresponding to the rotation angle of the floating member.
That is, the rotation angle of the floating member floating on the surface of the liquid stored in the reservoir may vary according to level change of the liquid. And, information corresponding to the rotation angle of the floating member is provided to a user through the display means. Accordingly, the user may easily check a remaining amount of the liquid.
The floating member may comprise a coupling portion rotatably fixed to inside of the reservoir, and an arm extending from the coupling portion.
The reservoir may comprise a light transmitting portion, and the coupling portion may be positioned below the light transmitting portion. The light transmitting portion may be implemented as a transparent window formed at a part of the reservoir, or may be implemented by forming the reservoir with a transparent material.
A display portion configured to display a rotated degree of the coupling portion may be formed on an outer circumferential surface of the coupling portion. The display portion may be implemented as calibrations arranged on the outer circumferential surface of the coupling portion. The calibrations may be implemented in the form of bars disposed on the outer circumferential surface with a constant interval therebetween. Alternatively, the calibrations may be implemented as a plurality of regions divided from each other on the outer circumferential surface and displayed in different colors. And, a remaining amount of the liquid corresponding to the rotated degree of the coupling portion may be directly displayed in the form of a numeric value, and a remaining amount of the liquid compared to a storage capacity of the liquid storage container may be displayed.
Among the calibrations, only a calibration corresponding to the remaining amount of the liquid may be displayed through the light transmitting portion. This may allow the user to more easily check the remaining amount of the liquid.
The reservoir may comprise an introduction opening through which liquid is introduced, and the arm may comprise a through hole. Even if the arm is rotated to a maximum degree due to level increase of the liquid, at least a part of the through hole may overlap the introduction opening. The through hole may prevent the arm upwardly moved at the time of liquid injection, from blocking the introduction opening, or prevent the liquid being injected into the introduction opening from being dispersed out with colliding with the arm.
The liquid storage container may further comprise a cover configured to open or close the introduction opening.
The coupling portion may comprise a stopper configured to limit a rotation angle of the floating member. The stopper may prevent a mal-operation of the floating member due to excessive rotation by rotating the floating member within a normal range.
According to another aspect of the present invention, there is provided a liquid storage container, comprising: a reservoir installed at a clothes dryer, and having an introduction opening through which liquid is introduced; a floating member floating on the liquid, rotatably disposed in the reservoir with a rotation angle variable according to a level of the liquid; and display means configured to display information corresponding to the rotation angle of the floating member.
According to still another aspect of the present invention, there is provided a clothes dryer, comprising: a body; a drum rotatably installed in the body; a liquid supplying apparatus configured to supply liquid material into the drum; and a liquid storage container comprising: a reservoir installed at the body, and configured to store liquid therein; a floating member floating on the liquid, and disposed on the reservoir with a rotation angle variable according to level change of the liquid inside the reservoir; and display means configured to display information corresponding to the rotation angle of the floating member.
The liquid storage container may be one of the aforementioned liquid storage containers.
According to yet still another aspect of the present invention, there is provided a clothes dryer, comprising: a body; a drum rotatably installed in the body; a liquid supplying apparatus configured to supply liquid material into the drum; and a liquid storage container comprising: a reservoir installed at the body, and having an introduction opening through which liquid is introduced; a floating member floating on the liquid, rotatably disposed in the reservoir with a rotation angle variable according to a level of the liquid; and display means configured to display information corresponding to the rotation angle of the floating member.
In the present invention, the rotation angle of the floating member may vary according to a remaining amount of the liquid. And, the remaining amount of the liquid may be informed to the user through the display means. Accordingly, the user may easily check the remaining amount of the liquid without checking the inside of the liquid storage container.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
In the drawings:
FIG. 1 is a perspective view of a clothes dryer having a liquid storage container according to a first embodiment of the present invention;
FIG. 2 is a sectional view taken along line ‘A-A’ in FIG. 1 ;
FIG. 3 is an enlarged perspective view of a floating member of FIG. 2 ;
FIG. 4 is a perspective view of a clothes dryer having a liquid storage container according to a second embodiment of the present invention; and
FIG. 5 is a sectional view taken along line ‘B-B’ in FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
Description will now be given in detail of the present invention, with reference to the accompanying drawings.
Hereinafter, a liquid storage container and a clothes dryer having the same according to the present invention will be explained in more detail with reference to the attached drawings.
FIGS. 1 to 3 show an inner structure of a clothes dryer having a liquid storage container according to a first embodiment of the present invention. FIG. 1 shows only an inner structure of the clothes dryer except for an outer panel. In the preferred embodiment of FIGS. 1 to 3 , the liquid storage container has been applied to the clothes dryer. However, the liquid storage container may be also is applied to any apparatus for containing specific liquid to be supplemented. For instance, the liquid storage container of FIG. 1 . may be also applied to a washing machine having a drying function.
An upper side of the clothes dryer constitutes an upper plate 10 . The upper plate 10 forms the appearance of the clothes dryer together with a front plate, side plates, and a rear plate. A front supporter 20 is disposed at a front side of the clothes dryer. The front supporter 20 is disposed on a front surface of a drum 30 , and rotatably supports the drum 30 together with a rear supporter (not shown).
A reservoir 100 for storing fragrant material therein is installed on a bottom surface of the upper plate 10 . The reservoir 100 may serve to store therein not only fragrant material, but also any liquid material. A fragrant material supplying pipe 110 connected to a nozzle (not shown) through which fragrant material is sprayed into the drum 30 is connected to one side surface of the reservoir 100 . And, a fragrant material discharging pipe 112 is connected to a bottom surface of the reservoir 100 . The fragrant material discharging pipe 112 serves to discharge fragrant material remaining in the reservoir 100 when other type of fragrant material is to be sprayed into the drum 30 .
A cut-out portion 12 is disposed on the upper plate 10 at a position above the reservoir 100 . The reservoir 100 is arranged so that an upper surface 102 can be partially exposed out through the cut-out portion 12 . An introduction opening 104 is penetratingly formed at the upper surface 102 . An orifice portion 106 is concavely formed at the periphery of the introduction opening 104 , thereby preventing fragrant material being injected into the introduction opening 104 from flowing to the periphery of the introduction opening 104 .
A light transmitting portion 120 is disposed so as to be adjacent to the introduction opening 104 , and is fixedly-inserted into a slot formed on the upper surface 102 . The light transmitting portion 120 is formed of a transparent or a semi-transparent material so that calibrations that will be later explained can be checked from the outside through the light transmitting portion 120 . Alternatively, the light transmitting portion 120 may be implemented by forming only a part of the upper surface 102 of the reservoir 100 with a transparent or a semi-transparent material. The light transmitting portion 120 may be also implemented by cutting a part of the upper surface 102 of the reservoir 100 without implementing an additional member inserted into the upper surface 102 .
A cover 130 for covering the cut-out portion 12 is installed at one side of the upper plate 10 . The cover 130 is coupled to the upper plate through the cover coupling portion 140 , and has a seal 134 at a position corresponding to the introduction opening 104 . The seal 134 is attached to a protrusion 132 having a shape corresponding to the orifice portion 106 .
Referring to FIGS. 2 and 3 , one pair of fixed arms 150 are formed in the reservoir 100 , and a floating member 160 is hinge-coupled to the fixed arms 150 . The floating member 160 is formed to float on the surface of liquid to be stored in the reservoir 100 . And, the floating member 160 includes a coupling portion 162 having a cylindrical shape and hinge-coupled to the fixed arms 150 , and an arm 164 extending from the coupling portion 162 .
Calibrations are formed on an outer circumferential surface of the coupling portion 162 with a constant interval therebetween. The calibration displays a remaining amount of the liquid stored in the reservoir 100 . Alternatively, the outer circumferential surface of the coupling portion 162 may be divided into a plurality of regions having different colors from each other so that the different colors can be seen through the light transmitting portion according to a remaining amount of the liquid.
Under these configurations, a floating height of the end of the arm 164 is varied according to level change of the liquid stored in the reservoir 100 , and thereby the coupling portion 162 is rotated. Accordingly, different calibrations are exposed through the light transmitting portion, thereby allowing a user to precisely check the remaining amount of the liquid. Preferably, a width of the light transmitting portion is controlled, thereby exposing only one calibration through the light transmitting portion. In this case, the exposed calibration has to display the current remaining amount of the liquid, through which the user can more rapidly check the remaining amount of the liquid.
A through hole 166 is formed near the end of the arm 164 . The through hole 166 is formed at a position overlapping the introduction opening 104 when the arm 164 is upwardly moved to a maximum degree. That is, since the introduction opening 104 is not blocked by the arm 164 even when the arm 164 is upwardly moved to a maximum degree, the liquid being injected into the introduction opening 104 is prevented from being dispersed out with colliding with the arm 164 .
A stopper for limiting a rotation angle of the arm 164 may be formed at the fixed arms. That is, two protrusions serving as the stopper may be formed at the fixed arms so that the arm 164 being rotated can be locked by the protrusions. As a result, a rotation angle of the arm 164 may be limited to a predetermined range.
FIG. 4 is a perspective view of a clothes dryer having a liquid storage container according to a second embodiment of the present invention. FIG. 4 shows only a part of the upper plate 10 of the clothes dryer for convenience.
A cut-out portion 12 is formed at the upper plate 10 , and a reservoir 200 is installed below the upper plate 10 on which the cut-out portion 12 is disposed. The reservoir 200 has an opened upper side, and a cover plate 202 is fitted into the cut-out portion 12 . The cover plate 202 includes an introduction opening 204 through which liquid for supplementation is introduced, and an orifice portion 206 formed at the periphery of the introduction opening 204 . And, the cover plate 202 also includes a light transmitting slot 220 adjacent to the orifice portion 206 and corresponding to the light transmitting portion 120 of FIG. 1 .
A cover 230 is hinge-coupled to the cut-out portion 12 . And, a seal 234 is disposed on an inner surface of the cover 230 in correspondence to the introduction opening 204 . The seal 234 is attached to a protrusion 232 having a shape corresponding to the orifice portion 206 .
Referring to FIG. 5 , a floating member 260 is installed in the reservoir 200 . And, the floating member 260 includes a coupling portion 262 hinge-coupled to the floating member 260 at a lower side, and an arm 264 extending from the coupling portion 262 . An outer circumferential surface of the coupling portion 262 is partially exposed out through the light transmitting slot 220 . And, calibrations are formed on the outer circumferential surface of the coupling portion 262 with a constant interval therebetween. The calibrations are exposed out of the cover plate 202 through the light transmitting slot 220 , thereby allowing the user to check the remaining amount of the liquid. On the outer circumferential surface of the coupling portion 262 , not only the calibrations, but also substantial numeric values or a plurality of regions having different colors may be displayed so as to directly display the remaining amount of the liquid.
A through hole 266 is formed near the end of the arm 264 . Like the through hole 166 of FIG. 1 , the through hole 266 is formed at a position overlapping the introduction opening 204 when the arm 264 is rotated to a maximum degree. Accordingly, the liquid being injected into the introduction opening 204 is prevented from being dispersed out with colliding with the surface of the arm 264 .
In the preferred embodiment, the cover plate 202 and the upper plate 10 are separately formed from each other. However, the cover plate 202 and the upper plate 10 may be integrally formed with each other.
The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.
As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the to foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims. | Disclosed are a liquid storage container and a clothes dryer having the same. The liquid storage container comprises: a reservoir installed at a clothes dryer, and configured to store liquid therein; a floating member floating on the liquid, and disposed on the reservoir with a rotation angle variable according to level change of the liquid inside the reservoir; and display means configured to display information corresponding to the rotation angle of the floating member. The rotation angle of the floating member may vary according to a remaining amount of the liquid. And, the remaining amount of the liquid may be informed to a user through the display means. Accordingly, the user may easily check the remaining amount of the liquid without checking the inside of the liquid storage container. | 3 |
[0001] The present application is a continuation and claims priority under 35 §USC 120 to U.S. application Ser. No. 13/890,082 filed May 8, 2013, which in turn claims priority under 35 §USC 119(e) to U.S. Provisional Application 61/708,105 filed Oct. 1, 2012, the entire contents of which are hereby incorporated by reference in their entireties.
FIELD OF THE INVENTION
[0002] In embodiments, the present invention relates to improved solvent formulations for the urease inhibitor N-(n-butyl) thiophosphoric triamide, hereafter referred to by its acronym NBPT. NBPT is a solid chemical substance, which is dissolved in a suitable solvent to allow application at low levels in the field. Additionally, solutions of NBPT are desirable when it is to be incorporated as a component of a granular mixed fertilizer, such that it can be deposited as a coating in a controlled and homogenous layer. In one embodiment, this invention proposes formulations of mixtures containing aprotic and protic solvents which are more environmentally friendly and are safer for workers to handle than known NBPT solutions. Moreover, performance advantages relative to NBPT solution stability, solution handling, and loading levels are disclosed for these new formulations.
BACKGROUND OF THE INVENTION
Description of the Prior Art
[0003] Nitrogen is an essential plant nutrient and is thought to be important for the adequate and strong foliage. Urea provides a large nitrogen content and is one of the best of all nitrogenous fertilizer materials, which consequently makes it an efficient fertilizer compound. In the presence of soil moisture, natural or synthetic ureas are converted to ammonium ion, which is then available for plant uptake. When applied as a fertilizer material, native soil bacteria enzymatically convert urea to two molar equivalents of ammonium ion for each mole of urea as demonstrated by the following two reactions:
[0000] CO(NH 2 ) 2 +2H 2 O→(NH 4 ) 2 CO 3
[0000] (NH 4 ) 2 CO 3 +2H + →2NH 4 + +CO 2 +H 2 O
[0004] In the presence of water, the ammonium thus produced is in equilibrium with ammonia. The equilibrium between NH 4 + and NH 3 is pH dependent, in accordance with the following equilibrium:
[0000] NH 4 + +OH − NH 3(solution) +H 2 O
[0005] As such, gaseous ammonia losses are higher at higher pH values. The flux of NH 3 from soil is primarily dependent on the NH 3 concentration, pH, and temperature. In the presence of oxygen, ammonium can also be converted to nitrate (NO 3 − ). Nitrogen in both its ammonium and nitrate forms may then be taken up as nutrient substances by growing plants.
[0006] The ammonium ion can also ultimately be converted to ammonia gas, which escapes to the air. The concentrations of NH 3 in the air and in solution are governed by Henry's law constant (H), which is a function of temperature:
[0000] └NH 3(air) ┘=H└NH 3(solution) ┘
[0007] Urea fertilizer is often just applied once at the beginning of the growing season. A weakness in this nitrogen delivery system involves the different rates at which ammonium and nitrate are produced in the soil, and the rate at which ammonium and nitrate are required by the plant during its growing season. The generation of ammonium and nitrate is fast relative to its uptake by plants, allowing a considerable amount of the fertilizer nitrogen to go unutilized or to be lost to the atmosphere as ammonia gas, where it is no longer available to the plant. Thus, there is a desire to control the hydrolysis of urea to ammonium and ammonia gas, thereby making the urea fertilizer more effective for plant growth.
[0008] Numerous methods have been developed for making urea fertilizers more effective, and for controlling the volatilization of ammonia from urea. Weston et al. (U.S. Pat. No. 5,352,265) details a method for controlling urea fertilizer losses, including: (1) multiple fertilizer treatments in the field, staged across the growing season, (2) the development of ‘controlled release’ granular fertilizer products, using protective coatings which erode slowly to introduce the urea to the soil in a controlled fashion, and (3) the discovery of simple chemical compounds (urease inhibitors) which inhibit the rate at which urea is metabolized by soil bacteria and converted to the ammonium ion.
[0009] Use of various urea coatings to provide urea in a controlled fashion to the plant has been widely demonstrated. Phosphate coatings for urea have been described by Barry et al. (U.S. Pat. No. 3,425,819) wherein the coating is applied to urea as an aqueous phosphate mixture. Miller (U.S. Pat. No. 3,961,932) describes the use of chelated micronutrients to coat fertilizer materials. Polymer coatings have also been disclosed which control the delivery of fertilizer materials (see, for example, U.S. Pat. No. 6,262,183 and U.S. Pat. No. 5,435,821).
[0010] Whitehurst et al. (U.S. Pat. No. 6,830,603) teach the use of borate salts to produce coated urea fertilizer, as a means of controlling ammonia losses during the growth cycle. Whitehurst summarizes numerous examples of this coating strategy to inhibit the loss of ammonia nitrogen in the soil. Accordingly, the prior art considers the merits of coated fertilizer products as one means of inhibiting the loss of ammonia nitrogen in the soil. Urease inhibiting materials other than NBPT have been disclosed. Some examples include the use of polysulfide and thiosulfate salts as taught by Hojjatie et al (US 2006/0185411 A1) and the use of dicyandiamide (DCD) and nitrapyrin.
[0011] Kolc at al. (U.S. Pat. No. 4,530,714) teach the use of aliphatic phosphoric triamide urease inhibitors, including the use of NBPT for this purpose. Kolc mentions the use of aqueous and organic carrier media, but specifies volatile (and flammable) solvents from the group including acetone, diisobutylketone, methanol, ethanol, diethyl ether, toluene, methylene chloride, chlorobenzene, and petroleum distillates. The principle reason for the use of these solvents was to assure that negligible amounts of solvent residue be retained on the crop.
[0012] Improved carrier systems for NBPT have been described subsequent to the Kolc. NBPT is both a hydrolytically and thermally unstable substance and several solvent systems have been developed to overcome these and other weaknesses. Unfortunately, the existing formulations are problematic in their own right due to thermal stability concerns and the toxicity of key formulation components.
[0013] Generally, it is desirable that solvents being used in conjunction with fertilizers be water soluble in all proportions which allows for facile dispersion at the point of use as well as a relatively high flashpoint (so that it has a reduced chances of explosions and/or fires at elevated temperatures). Many of the formulation solvents disclosed in U.S. Pat. No. 4,530,714 do not possess these desirable properties. Examples of such problematic solvents from this patent include the use of toluene, a flammable and water immiscible solvent.
[0014] Weston et al. (U.S. Pat. No. 5,352,265) disclose the use of pyrrolidone solvents, such as N-Methyl pyrrolidone (NMP), as does Narayanan et al. (U.S. Pat. No. 5,160,528 and U.S. Pat. No. 5,071,463). It is shown that a solvents of this type can dissolve high levels of NBPT to produce product concentrates and that the resulting concentrates have good temperature stability. These features are useful in that they allow commercial products to be stored, pumped, and transported in conventional ways.
[0015] In U.S. Pat. No. 5,698,003, Omilinsky and coworkers also disclose the use of ‘liquid amides” such as NMP in NBPT formulations. Omilinsky further speaks to the importance of solution stability and develops glycol-type solvents as desirable base solvents for NBPT delivery mixtures. The dominant role played by a liquid amide co-solvent is to depress the pour point of the mixture, which is insufficiently high as a consequence of the natural viscosity of glycols at reduced temperatures. NMP plays several roles in NBPT-based agrichemical formulations. As taught in '265, '528, and '463, NMP is a useful solvent capable of producing concentrated NBPT product formulations which have good temperature stability. It may also be used as an additive to depress the pour point of viscous base solvents, such as propylene glycol. Omilinsky discloses the use of NMP as a co-solvent to depress the pour point of propylene glycol in '003.
[0016] In mixtures such as those described in U.S. Pat. No. 5,698,003, the requirement for an additive to depress the pour point of glycol-type NBPT solvent formulations is described. Solvents such as propylene glycol have the attractive feature of being essentially nontoxic and are thus an attractive mixture component in agrichemical and pharmaceutical products. One drawback of some glycols is a relatively high viscosity level, which can make these materials resistant to flow and difficult to pour. Indeed, the dynamic viscosity at 25° C. of propylene glycol is 48.8 centipoise, almost 50 times that of water at the same temperature. Viscosity data for propylene glycol can be found in Glycols (Curme and Johnston, Reinhold Publishing Corp., New York, 1952). Omilinsky '003 describes the use of NMP as an additive capable of depressing the pour point of NBPT mixtures.
[0017] Although NMP and other liquid amide solvents play useful roles in the described NBPT formulations, concerns about the safety of these solvents has increased greatly in recent years. In particular, European Directives 67/548/EEC and/or 99/45/EC have recently classified N-methylpyrrolidone (NMP) as a reproductive toxin (R61) in amounts exceeding 5% of the product formulation. It is scheduled for listing on the European Union's ‘Solvent of Very High Concern’ list, which would preclude its use in industrial and agrichemical formulations. In the US, NMP is subject to California Proposition 65 (The Safe Drinking Water and Toxic Enforcement Act of 1986) requirements, which regulate substances known by the US State of California to cause cancer or reproductive harm.
[0018] Nothing in the prior art addresses the suitability of NMP in these formulations from the standpoint of safety, or proposes appropriate alternatives from the perspectives of both safety and performance.
[0019] Indeed, guidelines for the use of reaction solvents in the pharmaceutical industry also speak to the relatively poor safety profile of NMP. As reaction solvents may be present at residual levels in finished drug products such considerations are warranted. The International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) classifies NMP as a ‘solvent to be limited (Class 2)’ in its document Impurities: Guideline for Residual Solvents Q 3 C ( R 3).
[0020] NMP is potentially toxic if it is given directly to humans and/or animals. Moreover, it is possible that NMP may be toxic when it is ingested by higher order animals after passage through the food chain. For example, often times, fertilizers are not completely absorbed/used by fields/crops/plants on which they are used and the fertilizers end up in water-ways (such as fresh water, brackish water or salt water bodies). In those situations where at least a part of the fertilizer ends up in these bodies of water, they may be absorbed, ingested or otherwise taken in by organisms that are either directly or indirectly consumed by higher animals (such as humans). In these instances, it is possible that the fertilizer and/or compounds that are associated with said fertilizer may be directly and/or indirectly ingested by humans or higher animals and lead to toxicity to said humans. It is also possible that the fertilizers that end up in water ways may be directly ingested by higher animals/humans that drink the water.
[0021] Moreover, when toxic compounds that are associated with various fertilizers are used, not only may they be toxic to the higher animals but they also may be toxic to the animals lower in the food chain. At higher doses, this may mean die-off of the animals lower in the food chain, which consequently means that there may be economic consequences such as crop and/or animal die-off, which means lower profit margins and less food available.
[0022] In light of the above, it is desirable to develop formulations/fertilizers that are less toxic to the environment and to animals and humans.
[0023] An important feature of NBPT-based agrichemical formulation is their chemical stability in solution. Although such products are diluted with water at the point of use, NBPT undergoes hydrolysis in the presence of water. Aqueous solutions or emulsions of NBPT are therefore not practical from a commercial perspective and organic solvents are preferred as vehicles to deliver concentrated NBPT products. But NBPT is not chemically inert to all solvents, and its stability must be assessed in order to develop a product suitable to the needs of agrichemical users.
[0024] The stability of NBPT to NMP has been previously established in U.S. Pat. No. 5,352,265 (Weston et al.) and by Narayanan et al. (U.S. Pat. No. 5,160,528 and U.S. Pat. No. 5,071,463).
[0025] Beyond the consideration of NBPT chemical stability in the presence of formulation solvents is the inherent stability of the solvents themselves to hydrolysis. As NBPT products are often ultimately dispersed into water, the hydrolytic stability of liquid amide solvents like NMP is a consideration.
[0026] At elevated temperatures and pH levels, NMP hydrolysis can be significant (“M-Pyrrol” product bulletin, International Specialty Products, p. 48).
SUMMARY OF THE INVENTION
[0027] In one embodiment, the present invention relates to liquid formulations containing N-(n-butyl) thiophosphoric triamide (NBPT). In an embodiment, the formulations can be made by dissolving the NBPT into an aprotic solvent consisting of a) dimethyl sulfoxide, b) dialkyl, diaryl, or alkylaryl sulfoxide having the formula R 1 —SO—R 2 , when R 1 is methyl, ethyl, n-propyl, phenyl or benzyl and R 2 is ethyl, n-propyl, phenyl or benzyl, c) sulfolane, d) ethylene carbonate, propylene carbonate, or mixtures thereof. In an embodiment, these formulations can be mixed with a protic component consisting of 1) an alcohol or polyol from the family of alkylene and poly(alkylene) glycols (PG), 2) an alkylene glycol from the group comprised of ethylene, propylene, or butylene glycol, 3) glycerin, 4) an alkanolamine from the group comprising ethanolamine, diethanolamine, dipropanolamine, methyl diethanolamine, monoisopropanolamine and triethanolamine, and/or 5) ethyl, propyl, or butyl lactate. In one embodiment, we propose the use of dimethyl sulfoxide (DMSO) as a replacement in NBPT-based agrichemical products for more toxic solvents such as, for N-methyl pyrrolidone.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0028] FIG. 1 shows accelerated chemical stability of NBPT solutions comparing the test product (50% PG, 25% DMSO, 25% NBPT) vs. the commercial product containing N-methyl pyrrolidone. The stability testing was conducted at 50° C., and concentrations were assayed by HPLC.
[0029] FIG. 2 shows accelerated chemical stability of NBPT solutions comparing the test product (35% PG, 40% DMSO, 25% NBPT) vs. the commercial product containing N-methyl pyrrolidone. The stability testing was conducted at 50° C., and concentrations were assayed by HPLC.
[0030] FIG. 3 shows accelerated chemical stability of NBPT solutions comparing the test product (20% PG, 40% DMSO, 40% NBPT) vs. the commercial product containing N-methyl pyrrolidone. The stability testing was conducted at 50° C., and concentrations were assayed by HPLC.
[0031] FIG. 4 shows accelerated chemical stability of NBPT solutions comparing the test product (48.5% glycerine, 1.5% methanol, 25% DMSO, 25% NBPT) vs. the commercial product containing N-methyl pyrrolidone. The stability testing was conducted at 50° C., and concentrations were assayed by
[0032] FIG. 5 shows accelerated chemical stability of NBPT solutions comparing the test product (48.5% glycerine, 1.5% methanol, 25% DMSO, 25% NBPT) vs. the commercial product containing N-methyl pyrrolidone. The stability testing was conducted at 50° C., and concentrations were assayed by HPLC.
[0033] FIG. 6 shows accelerated chemical stability of four NBPT solutions: Mix A; 75.0% N-methyl pyrrolidone, 25% NBPT. Mix B; 75 PG, 25% NBPT. Mix C; 75.0% Buffered mix, 25.0% NBPT. Mix D; 75% DMSO, 25.0% NBPT. The stability testing was conducted at 50° C., and concentrations were assayed by HPLC.
[0034] FIG. 7 shows viscosity testing results comparing mixtures of propylene glycol with varying percentages of co-solvents DMSO vs. NMP. Viscosities were measured using a Brookfield LVDV-E digital rotational viscometer with LVDV-E spindle set. Also shown is the viscosity of the commercial NBPT product, which contains NMP and PG, of example 2.
[0035] FIG. 8 shows viscosity testing results comparing mixtures of glycerol with varying percentages of co-solvents DMSO vs. NMP. Viscosities were measured using a Brookfield LVDV-E digital rotational viscometer with LVDV-E spindle set. Also shown is the viscosity of the commercial NBPT product, which contains NMP and PG, of example 2.
[0036] FIG. 9 shows viscosity testing results comparing mixtures of monoisopropanolamine (MIPA) with varying percentages of co-solvents DMSO vs. NMP. Viscosities were measured using a Brookfield LVDV-E digital rotational viscometer with LVDV-E spindle set. Also shown is the viscosity of the commercial NBPT product, which contains NMP and PG, of example 2.
[0037] FIG. 10 shows ammonia emissions testing results from soil which had been applied commercial urea fertilizer vs. commercial urea fertilizer coated with an NBPT solution containing 50.0% PG, 30.0% DMSO, and 20.0% NBPT by weight. The testing was conducted for 7 days at 22° C. using a commercially available potting soil blend, and was analyzed using a chemiluminescence ammonia analyzer.
DETAILED DESCRIPTION OF THE INVENTION
[0038] In an embodiment, the present invention relates to formulations containing N-(n-butyl) thiophosphoric triamide (NBPT). In an embodiment, these formulations are prepared by dissolving NBPT into an aprotic solvent consisting of a) dimethyl sulfoxide, b) dialkyl, diaryl, or alkylaryl sulfoxide having the formula R 1 —SO—R 2 , when R 1 is methyl, ethyl, n-propyl, phenyl or benzyl and R 2 is ethyl, n-propyl, phenyl or benzyl, c) sulfolane, d) ethylene carbonate, propylene carbonate, or mixtures thereof. In an embodiment, these formulations can be mixed with a protic component consisting of 1) an alcohol or polyol from the family of alkylene and poly(alkylene) glycols (PG), 2) an alkylene glycol from the group comprised of ethylene, propylene, or butylene glycol, 3) glycerin, 4) an alkanolamine from the group comprising ethanolamine, diethanolamine, dipropanolamine, methyl diethanolamine, monoisopropanolamine and triethanolamine, and/or 5) ethyl, propyl, or butyl lactate.
[0039] In one embodiment, dimethyl sulfoxide (DMSO) is used as a replacement in NBPT-based agrichemical products for more toxic solvents such as, for N-methyl pyrrolidone (NMP). In one embodiment, the solution is either combined with a dry granular or liquid urea fertilizer and applied to cropland to make the fertilizer more effective for plant growth, and/or applied directly to urea-containing lands, surfaces, or products to reduce ammonia emissions.
[0040] In one embodiment, coated granular urea products containing additional plant nutrients can be prepared from granular urea, a source or sources of the additional nutrients in powdered form and the diluted NBPT containing mixture described below. Granular urea can be first dampened with the diluted NBPT containing mixture followed by mixing to distribute the NBPT containing liquid mixture over the granular urea surface using any commonly used equipment to commingle a liquid with a granular solid. After distribution of the diluted NBPT containing mixture over the granular surface, the additional nutrients in powdered form can be added to the dampened mixture and the resulting combined ingredients can be further mixed to distribute the powdered materials. In an alternate embodiment, the powdered materials may be first mixed with the granular urea and then the NBPT containing diluted mixture can be sprayed onto a tumbling bed of the dry ingredients to agglomerate the dry materials. This latter method may be particularly suited to continuous processing.
[0041] The term “urea fertilizer” as used herein refers to both natural and synthetic ureas, either used alone or mixed with other macro- and/or micronutrients and/or organic matter. Dry granular urea fertilizer contains about 46% nitrogen by weight.
[0042] In one embodiment, the compounds listed in this invention as aprotic and protic solvents may be described generally as sulfoxides and alcohols, respectively.
[0043] In an embodiment, the present invention relates to the use of safer and more environmentally friendly solvents to overcome the limitations of specific existing urease inhibitor formations. In an embodiment, the solvents used in the present invention are less toxic than the solvents that have been used in the prior art, for example, NMP.
[0044] In an embodiment, the formulations use combinations of polar aprotic solvents (sulfoxides, sulfones, dialkyl carbonates) with protic solvents (glycols, triols, and alkanolamines) to produce NBPT formulations having acceptable viscosity levels and high NBPT loading while also being relatively non-toxic. Moreover, in an embodiment, the protic/aprotic solvent mixtures demonstrate excellent NBPT stability as demonstrated by accelerated stability testing.
[0045] One aspect of the invention involves the use of dimethyl sulfoxide as a replacement for the more hazardous liquid amide component in formulations requiring such a co-solvent to modify the formulation's flow properties. In this aspect, this is a considerable improvement in light of increased regulatory scrutiny of the liquid amide solvents.
[0046] In one embodiment, the present invention relates to the use of DMSO with NBPT instead of NMP. NMP has a recognized reproductive toxicity and an examination of acute toxicity data shows that NMP is considerably more hazardous than dimethyl sulfoxide, by any exposure route. A summary of basic toxicological indicators is given in Table 1.
[0000]
TABLE 1
Comparative acute/reproductive toxicity data for dimethyl
sulfoxide and N-methyl pyrrolidone.
Toxicological indicator
Dimethyl sulfoxide
N-methyl pyrrolidone
CAS
[67-58-4]
[872-50-4]
Oral LD-50
14,500-28,300
3,914
Dermal LD-50
40,000
8,000
Inhalation toxicity
None established
3200 μg/day
(MADL)
Reproductive toxin
no
yes
MADL = Maximum Allowable Dosage Level per day (California Proposition 65)
[0047] As shown in the table above, it should be clear to those of ordinary skill in the art that DMSO is significantly less toxic than NMP. Furthermore, DMSO is classified as ‘a solvent with low toxic potential (Class 3)’—the most favorable rating.
[0048] In one embodiment, the present invention addresses the shortcomings of solvents of the prior art by the use of specific mixtures of low toxicity polar aprotic solvents (most principally dimethyl sulfoxide) and various common protic solvents, that also tend to be relatively non-toxic.
[0049] In an embodiment, the present invention relates to formulations comprising aprotic/protic solvent mixtures that are used to fluidize the specific urease inhibitor N-(n-butyl) thiophosphoric triamide such that it might be used to coat fertilizer products.
[0050] In one embodiment, phosphate coatings for urea may be used wherein the coating is applied to urea as an aqueous phosphate mixture prior to adding the fertilizer additive of the present invention.
[0051] In an embodiment, chelated micronutrients may be used to coat fertilizer materials. Alternatively and/or additionally, polymer coatings may be used which control the delivery of fertilizer materials.
[0052] In one embodiment, the formulations of the present invention use DMSO as a solvent. DMSO has an advantage over prior art solvents such as NMP because DMSO does not undergo the hydrolysis that can be significant with NMP (see “M-Pyrrol” product bulletin, International Specialty Products, p. 48). Accordingly, when one uses DMSO, one has significantly more latitude in formulation development.
[0053] Further, the solvent properties of DMSO are useful in these formulations in that NBPT concentrations containing over 50 wt. % NBPT are attainable. Such high loading of an active substance by a solvent enables the manufacture of product concentrates, which can be less expensive to store, transport and use. When the fertilizer additive product arrives at the user, the user is able to dilute the concentrate with water and use the fertilizer additive (with fertilizer) for their crops/plants or the like.
[0054] In one embodiment, NBPT is dissolved into an aprotic solvent such as dimethyl sulfoxide. The NBPT-aprotic solvent solution may be used alone, or further mixed with a protic solvent to improve product handling, stability, and/or pourability of the solution.
[0055] The mixing of the materials may be accomplished in any commonly used method: for example; simply tank mixing materials prior to use, using a metering system to inject materials simultaneously, or mixing via a spray injection system.
[0056] In one embodiment, the NBPT/aprotic solvent/protic solvent mixture is mixed to produce a NBPT concentration of 5% to 75% by weight. Alternatively, a NBPT concentration of 5% to 60% by weight may be used. Alternatively, a NBPT concentration of 5% to 50% by weight may be used. Alternatively, a NBPT concentration of 5% to 40% by weight may be used. The initial solubilizing step in dimethyl sulfoxide can be accomplished between room temperature about 19° C. up to about 150° C. (the boiling point of DMSO at atmospheric pressure is ˜190° C.). Alternatively, the solubilizing step in dimethyl sulfoxide can be accomplished between about 22° C. and up to 60° C.
[0057] The mixture can be mixed in any common mixing tank. Although the metering of NBPT, aprotic solvent, and protic solvent can be based on a weight, it may also be based on a volumetric basis.
[0058] A dye or colorant can be added to the mixture to aid in visual assessment of uniform coating during the coating of granular urea. Alternatively, a dye or colorant can be added to the mixture to aid in visual assessment of uniform coating during the coating of urea in aqueous mixtures just prior to application. In one embodiment, the colorant can include any nontoxic common food dye.
EXAMPLES
[0059] The following examples are provided to illustrate the practice of the invention. The examples are not intended to illustrate the complete range of possible uses. All compositions are based on mass percentages unless expressly stated. Concentrations of individual components are presented before their name. For example, 20.0% NBPT refers to a mixture containing 20.0% NBPT by weight.
Example 1
[0060] An NBPT solution was prepared by thoroughly mixing NBPT, DMSO, and PG to obtain the following percentages by weight: 50.0% PG, 30.0% DMSO, 20.0% NBPT.
Example 2
[0061] To test for the toxicity of DMSO and compare it to the relative toxicity of NMP, a 96 hr. acute toxicity range-finding test was conducted on juvenile crayfish ( Procambarus clarkii ) to estimate the lethal concentration to half of the population (LC 50 ) for the solution as described in example 1. Simultaneously, the LC 50 was determined on a commercially available NBPT solution which contained 26.7% NBPT by weight (per product label), and approximately 10% N-methyl pyrrolidone (MSDS range 10-30%), and approximately 63% propylene glycol (MSDS range 40-70%). Crayfish were placed into static chambers and exposed to equal NBPT concentrations of 0, 72, 145, 290, 580, and 1160 mg/L in clean water. The LC 50 of the solution of example 1 was 145 mg NBPT (as active ingredient)/L, while the LC 50 of Agrotain® Ultra was 75 mg NBPT (as active ingredient)/L. Because a higher LC 50 value indicates lower toxicity, the solution of example 1 was approximately half as toxic as the commercial product which contained N-methyl pyrrolidone.
[0062] This test demonstrates that the formulations of the present invention are significantly less toxic than the formulations of the prior art.
Example 3
[0063] NBPT solutions were prepared in DMSO and equal amounts of DMSO/PG to determine the maximum solubility at room temperature of 22° C. Following mixing and sonification, the samples were visually inspected, then filtered through a 0.45 μm filter and analyzed by near infrared reflectance spectrometry. At 22° C., the solubility of NBPT in DMSO was at least 58.9% by weight. The solubility of NBPT in equal amounts of DMSO/PG was at least 55.0% by weight.
[0064] It would be expected that at increased temperatures beyond that disclosed above, one might be able to increase the solubility of NBPT above the amounts found in this example providing an avenue for concentrates. Even if the temperature is lowered during transport, instructions on the use of the fertilizer additive may instruct the user to raise the temperature of the formulation to assure complete solubilization of the product prior to use.
Example 4
[0065] An NBPT solution was prepared by thoroughly mixing NBPT, DMSO, and PG to obtain the following percentages by weight: 50% PG, 25% DMSO, and 25% NBPT. The commercially available NBPT solution of example 2 was also used for comparison.
Example 5
[0066] The NBPT solutions of example 4 were placed into individual vials and incubated for 45 days at 50±1° C. in a laboratory oven. Samples were periodically removed for analysis of NBPT in solution using a Waters model 1525 High Performance Liquid Chromatograph (HPLC) equipped with a Waters 2489 tunable UV/visible detector. Suitable analytical parameters (mobile phase composition, column selection, etc.) such as would occur to workers knowledgeable in the art were employed, and raw data from the HPLC analyses were calibrated against authentic standards of NBPT having a nominal purity of >99%. FIG. 1 shows the results of the accelerated stability testing.
[0067] This test shows that the NBPT did not have significant deterioration at elevated temperatures meaning that the formulations of the present invention can be transported without worrying about significant degradation of the product.
Example 6
[0068] An NBPT solution was prepared by thoroughly mixing NBPT, DMSO, and PG to obtain the following percentages by weight: 35% PG, 40% DMSO, and 25% NBPT. The commercially available NBPT solution of example 2 was also used for comparison.
Example 7
[0069] The NBPT solutions of example 6 were placed into individual vials and incubated for 45 days at 50±1 ° C. in a laboratory oven. Samples were periodically removed and analyzed using the procedures of example 5. FIG. 2 shows the results of the accelerated stability testing.
[0070] This test shows that the NBPT did not have significant deterioration at elevated temperatures when the relative amounts of DMSO are varied. Accordingly, the formulations of the present invention can be transported without worrying about significant degradation of the product at different DMSO levels.
Example 8
[0071] An NBPT solution was prepared by thoroughly mixing NBPT, DMSO, and PG to obtain the following percentages by weight: 20% PG, 40% DMSO, and 40% NBPT. The commercially available NBPT solution of example 2 was also used for comparison.
Example 9
[0072] The NBPT solutions of example 8 were placed into individual vials and incubated for 45 days at 50±1° C. in a laboratory oven. Samples were periodically removed and analyzed using the procedures of example 5. FIG. 3 shows the results of the accelerated stability testing.
[0073] This test shows that the NBPT did not have significant deterioration at elevated temperatures when the relative amount of NBPT is increased. Accordingly, the formulations of the present invention can be transported without worrying about significant degradation of the product even at a relatively high NBPT concentration.
Example 10
[0074] An NBPT solution was prepared by thoroughly mixing NBPT, DMSO, glycerine, and methanol to obtain the following percentages by weight: 48.5% glycerine, 1.5% methanol, 25% DMSO, and 25% NBPT. The commercially available NBPT solution of example 2 was also used for comparison.
Example 11
[0075] The NBPT solutions of example 10 were placed into individual vials and incubated for 45 days at 50±1° C. in a laboratory oven. Samples were periodically removed and analyzed using the procedures of example 5. FIG. 4 shows the results of the accelerated stability testing.
[0076] This test shows that the NBPT did not have significant deterioration at elevated temperatures with this formulation meaning that this formulation can be transported without worrying about significant degradation of the product.
Example 12
[0077] An NBPT solution was prepared by thoroughly mixing NBPT, DMSO, glycerine, and methanol to obtain the following percentages by weight: 33.5% glycerine, 1.5% methanol, 25% DMSO, and 40% NBPT. The commercially available NBPT solution of example 2 was also used for comparison.
Example 13
[0078] The NBPT solutions of example 12 were placed into individual vials and incubated for 45 days at 50±1° C. in a laboratory oven. Samples were periodically removed and analyzed using the procedures of example 5. FIG. 5 shows the results of the accelerated stability testing.
[0079] This test shows that the NBPT did not have significant deterioration at elevated temperatures with this formulation meaning that this formulation can be transported without worrying about significant degradation of the product.
Example 14
[0080] A buffer solution was prepared by carefully mixing monoisopropanolamine (MIPA) with glacial acetic acid (GAA) to obtain the following percentages by weight: 62.5% MIPA, 37.5% GAA. The mixing was conducted such that the temperature of the mixture remained below 50° C. Multiple NBPT solutions were prepared to obtain the following percentages by weight:
[0081] Mix A: 75% N-methyl pyrrolidone, 25% NBPT; Mix B: 75% PG, 25% NBPT; Mix C: 75% Buffer Solution, 25% NBPT; Mix D: 75% DMSO, 25% NBPT.
Example 15
[0082] The four NBPT solutions of example 14 were placed into individual vials and incubated for approximately 200 hrs. at 50±1° C. Samples were periodically removed and analyzed using the HPLC procedures of example 5. FIG. 6 shows the results of the accelerated stability testing.
[0083] This test shows that Mix C had more sample degradation at elevated temperatures than mixtures containing DMSO(Mix D), NMP (Mix A) or PG (Mix B). It should be noted that PG does not have the pourability of DMSO and NMP is more toxic than DMSO.
Example 16
[0084] Dynamic viscosity measurements were collected for propylene glycol, glycerin, and a representative alkanolamine (monoisopropanolamine, MIPA) with increasing levels of DMSO and NMP. A Brookfield LVDV-E digital rotational viscometer with LVDV-E spindle set (Brookfield Engineering Labs, Inc., Middleboro, Mass.) was employed for this work and was calibrated using Cannon N14 general purpose, synthetic base oil viscosity calibration standard solution (Cannon Instrument Company, State College, Pa.). The sampling was conducted at 21° C. FIGS. 7, 8, and 9 display the ability of DMSO to depress the viscosity of NBPT mixtures at 21° C. as a function of concentration, relative to similar NMP measurements.
[0085] This test shows that there is virtually no difference between DMSO and NMP in reducing the viscosity of various viscous formulations.
Example 17
[0086] A dye solution was added to the solution of example 1. 454 grams of granular urea was added to two clean, dry glass 2000 mL media bottles. Using a pipette, 1.87 mL, to represent application rate of 2 quarts product/ton urea of the dyed solution in example 1, was added to the urea in one of the bottles. Using a pipette, 1.87 mL, to represent application rate of 2 quarts product/ton urea of the commercial solution of example 2, was added to the urea in the other bottle. With the lid on, the media bottles were rotated hand over hand (1 rotation=360-degree hand over hand turn) until the urea was consistently coated. More complete coverage was observed after four turns in the dyed solution of example 1. The number of rotations required to obtain 100% visual coverage was recorded. The dyed solution of example 1 required 30 rotations for complete coverage, while the commercial product of example 2 required 35 rotations.
[0087] This test shows that formulations containing DMSO and a dye can more easily cover urea than a corresponding solution containing NMP and a dye.
Example 18
[0088] The NBPT solutions of examples 4, 6, 8, 10, and 12, together with the commercial NBPT solution of example 2, were placed in a −20° C. freezer for 48 hrs. The NBPT solutions of examples 4, 6, 8, and the commercial NBPT solution of example 2, were all freely flowable at −20° C. The NBPT solution of example 10 was very viscous but still flowable. The NBPT solution of example 12 was a solid at −20° C.
Example 19
[0089] Commercial granulated urea was treated with the NBPT solution of example 1. Both untreated and treated urea were applied to a commercially available potting soil blend at 22° C., and ammonia concentrations in the headspace were measured for a 7-day period using a chemiluminescence analyzer. Ammonia concentrations in the treated urea were considerably less than those in the untreated urea. FIG. 10 shows the results of the ammonia emissions testing.
[0090] This test shows that NBPT formulations containing DMSO are effective at reducing the hydrolysis of urea to ammonium, thereby reducing ammonia losses to the atmosphere and making the fertilizer more effective.
[0091] In certain embodiments, the present invention relates to formulations, fertilizer additives, methods and processes of making and using these formulations and/or fertilizer additives.
[0092] In an embodiment, the present invention relates to a formulation comprising N-(n-butyl) thiophosphoric triamide and one or more of an C 1-6 alkylene carbonate and R 1 S(O)xR 2 wherein R 1 and R 2 are each independently a C 1-6 alkylene group, an aryl group, or C 1-3 alkylenearyl group or R 1 and R 2 with the sulfur to which they are attached form a 4 to 8 membered ring wherein R 1 and R 2 together are a C 1-6 alkylene group which optionally contains one or more atoms selected from the group consisting of O, S, Se, Te, N, and P in the ring and x is 1 or 2. In a variation, the atoms in the ring may optionally include O, S, N and P or alternatively, O, S, and N.
[0093] In one embodiment, the formulation contains R 1 S(O)xR 2 , which is dimethyl sulfoxide. Alternatively, the formulation contains R 1 S(O)xR 2 , which is a dialkyl, diaryl, or alkylaryl sulfoxide. Alternatively, R 1 and R 2 may be the same or different and each of R 1 and R 2 may be C 1-6 alkylene group, an aryl group, or C 1-3 alkylenearyl group.
[0094] In an embodiment, R 1 is methyl, ethyl, n-propyl, phenyl or benzyl and R 2 is methyl, ethyl, n-propyl, phenyl or benzyl or mixtures thereof In another embodiment, R 1 S(O)xR 2 is sulfolane.
[0095] In an embodiment, the formulation may contain akylene carbonate, which is ethylene carbonate, propylene carbonate, butylene carbonate or mixtures thereof. In a variation, the formulation may contain akylene carbonate, which is ethylene carbonate, propylene carbonate, or mixtures thereof
[0096] In an embodiment, the formulation may further comprise an alcohol or polyol wherein the polyol is alkylene or poly(alkylene) glycols or mixtures thereof. In an embodiment, the polyol is an alkylene glycol selected from the group consisting of ethylene, propylene, and butylene glycol, or mixtures thereof. In an embodiment, the polyol is glycerin.
[0097] In an embodiment, the formulation may further comprise an alkanolamine selected from the group consisting of ethanolamine, diethanolamine, dipropanolamine, methyl diethanolamine, monoisopropanolamine and triethanolamine.
[0098] The formulation(s) may contain an aqueous ethanolamine borate such as ARBORITE Binder. In one embodiment, the concentration of the secondary or tertiary amino alcohol may be kept above about 12% and alternatively, above about 20%. When the concentration of aqueous ethanolamine borate is below about a 12% concentration, a suspension of NBPT in the aqueous mixture may form which can be solved by agitation to be used to prepare other products.
[0099] In an embodiment of the invention, NBPT may be dissolved by melting the compound with sufficient triethanolamine to provide a mixture with up to about 30% by weight of NBPT. The resulting NBPT mixture in triethanolamine can be used to treat urea as described herein.
[0100] In another embodiment of the invention, NBPT is dissolved in diethanolamine in an amount up to 40% by weight by melting the solid into diethanolamine until a solution is obtained. The NBPT diethanolamine mixture may be used to treat urea as described herein.
[0101] In another embodiment of the invention, a liquid mixture of diisopropanolamine may be prepared by gently warming the solid until it has liquefied and the mixing NBPT with the solid up to the solubility limit. The liquid NBPT containing mixture in disioproanolamine may be used to treat urea as described herein.
[0102] In a variation, the formulation may further comprise ethyl, propyl, or butyl lactate.
[0103] In an embodiment, the N-(n-butyl)-thiophosphoric triamide (NBPT) may be present in an amount that is between about 5-75 wt. % of the formulation. In a variation, the formulation may contain between about 10 and 75 wt. % NBPT, 10 and 50 wt. % DMSO, and 10 and 80 wt. % PG (poly glycol) or alkylene carbonate. In a variation, the formulation may contain between about 10 and 60 wt. % NBPT, 10 and 40 wt. % DMSO, and 10 and 60 wt. % PG or alkylene carbonate. In a variation, the formulation may contain between about 10 and 50 wt. % NBPT, 10 and 50 wt. % DMSO, and 10 and 50 wt. % PG or alkylene carbonate. In a variation, the formulation may contain between about 10 and 40 wt. % NBPT, 10 and 40 wt. % DMSO, and 10 and 50 wt. % PG or alkylene carbonate. In a variation, the formulation may contain between about 20 and 50 wt. % NBPT, 20 and 50 wt. % DMSO, and 10 and 50 wt. % PG or alkylene carbonate. In a variation, the formulation may be diluted with water.
[0104] In an embodiment, the present invention relates to a fertilizer additive comprising N-(n-butyl) thiophosphoric triamide and one or more of an C 1-6 alkylene carbonate and R 1 S(O)xR 2 wherein R 1 and R 2 are each independently a C 1-6 alkylene group, an aryl group, or C 1-3 alkylenearyl group or R 1 and R 2 with the sulfur to which they are attached form a 4 to 8 membered ring wherein R 1 and R 2 together are a C 1-6 alkylene group which optionally contains one or more atoms selected from the group consisting of O, S, Se, Te, N, and P in the ring and x is 1 or 2.
[0105] In an embodiment, the fertilizer additive may comprise N-(n-butyl)-thiophosphoric triamide and dimethyl sulfoxide. In a variation, the fertilizer may further comprise polyalkylene glycols. In a variation, the polyalkylene glycols are selected from the group consisting of polymethylene glycols, polyethylene glycols, polypropylene glycols, polybutylene glycols, and mixtures thereof.
[0106] In an embodiment, the fertilizer additive may be any of the embodiments discussed above as it relates to the formulation.
[0107] In an embodiment, the present invention relates to a method of reducing the volatility of urea fertilizers comprising adding a composition that comprises N-(n-butyl)-thiophosphoric triamide and one or more of an C 1-6 alkylene carbonate and R 1 S(O)xR 2 wherein R 1 and R 2 are each independently a C 1-6 alkylene group, an aryl group, or C 1-3 alkylenearyl group or R 1 and R 2 with the sulfur to which they are attached form a 4 to 8 membered ring wherein R 1 and R 2 together are a C 1-6 alkylene group which optionally contains one or more atoms selected from the group consisting of O, S, Se, Te, N, and P in the ring and x is 1 or 2.
[0108] In an embodiment, the present invention relates to a method of making a formulation and/or fertilizer additive, wherein to N-(n-butyl)-thiophosphoric triamide is added one or more of an C 1-6 alkylene carbonate and R 1 S(O)xR 2 wherein R 1 and R 2 are each independently a C 1-6 alkylene group, an aryl group, or C 1-3 alkylenearyl group or R 1 and R 2 with the sulfur to which they are attached form a 4 to 8 membered ring wherein R 1 and R 2 together are a C 1-6 alkylene group which optionally contains one or more atoms selected from the group consisting of O, S, Se, Te, N, and P in the ring and x is 1 or 2.
[0109] In an embodiment, the methods may comprise R 1 S(O)xR 2 , which is dimethyl sulfoxide.
[0110] In an embodiment, the methods may comprise C 1-6 alkylene carbonate, which is ethylene carbonate, propylene carbonate, butylene carbonate or mixtures thereof.
[0111] In an embodiment, the methods may comprise any of the formulations and/or fertilizer additives discussed above.
[0112] Every patent mentioned herein is incorporated by reference in its entirety.
[0113] It should be understood that the present invention is not to be limited by the above description. Modifications can be made to the above without departing from the spirit and scope of the invention. It is contemplated and therefore within the scope of the present invention that any feature that is described above can be combined with any other feature that is described above. Moreover, it should be understood that the present invention contemplates minor modifications that can be made to the formulations, compositions, fertilizer additives and methods of the present invention. When ranges are discussed, any number that may not be explicitly disclosed but fits within the range is contemplated as an endpoint for the range. The scope of protection to be afforded is to be determined by the claims which follow and the breadth of interpretation which the law allows. | An improved solvent system for the formulation and application of N-alkyl thiophosphoric triamide urease inhibitors. These formulations provide safety and performance benefits relative to existing alternatives and enable storage, transport and subsequent coating or blending with urea based or organic based fertilizers. These formulations are comprised primarily of environmentally friendly aprotic and protic solvents (particularly dimethyl sulfoxide and alcohols/polyols) to stabilize the urease inhibitor. | 2 |
REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 12/813,621 filed Jun. 11, 2010 which is incorporated by reference in its entirety. This application claims the right of priority based on TW application Serial No. 098119860 filed on Jun. 12, 2009, which is incorporated herein by reference and assigned to the assignee herein.
TECHNICAL FIELD
The application relates to an optoelectronic device, and more particularly to an optoelectronic device including a first transparent conductive oxide layer and a second transparent conductive oxide layer.
DESCRIPTION OF BACKGROUND ART
The lighting theory of light-emitting diode (LED), which is different from that of incandescent lamp, is to generate light by releasing the energy generated from the move of the electron between n type semiconductor and p type semiconductor. So the LED is called a cold lighting source. Furthermore, since LED has advantages as highly durable, long life-time, light weight, low power loss, nowadays LED is highly expected to be a new generation lighting device in the lighting market.
FIG. 1 is a diagram of a conventional optoelectronic element 100 including a substrate 10 , a semiconductor stacked layer 12 disposed on the substrate 10 , and at least an electrode 14 disposed on the semiconductor stacked layer 12 , wherein from top to bottom the semiconductor stacked layer 12 includes a first conductive type semiconductor layer 120 , an active layer 122 , and a second conductive type semiconductor layer 124 .
In the conventional optoelectronic element 100 , the surface of the semiconductor stacked layer 12 is flat, and the refractive index of the semiconductor stacked layer 12 is different from that of the external environment, so the light emitted from the active layer has total internal reflection (TIR) easily.
Moreover, when the conventional optoelectronic element 100 is in operation, the current flows into the semiconductor stacked layer 12 via the electrode 14 . Most of the current flows in the semiconductor stacked layer 12 by a shortest route, therefore the current distributes in the semiconductor stacked layer 12 unevenly, and the illumination efficiency of the optoelectronic element 100 is affected.
Besides, the optoelectronic element 100 can further connects to other elements to form an optoelectronic apparatus. FIG. 2 is a structure diagram of a conventional optoelectronic apparatus. As shown in FIG. 2 , an optoelectronic apparatus 200 includes: a sub-mount 20 at least having a circuit 202 ; at least a solder 22 disposed on the sub-mount 20 to attach the optoelectronic element 100 on the sub-mount 20 , and electrically connects the substrate 10 of the optoelectronic element 100 to the circuit 202 ; and an electrical connection structure 24 for electrically connecting the electrode 14 of the optoelectronic element 100 to the circuit 202 of the sub-mount 20 , wherein the sub-mount 20 can be a lead frame or a mounting structure for circuitry planning of the optoelectronic apparatus 200 and for enhancing the heat-dissipation.
SUMMARY OF THE DISCLOSURE
The present application discloses an optoelectronic element comprising a semiconductor stack layer; a first transparent conductive oxide layer located on the semiconductor stack layer, wherein the first transparent conductive oxide layer has at least an opening; and a second transparent conductive oxide layer covering the first transparent conductive oxide layer, wherein the second transparent conductive oxide layer is filled into the opening of the first transparent conductive oxide layer and contacted with the semiconductor stack layer, and any one of the first transparent conductive oxide layer and the second transparent conductive oxide layer forms an ohmic contact with the semiconductor stack layer.
The present application further discloses an optoelectronic element comprising a semiconductor stack layer; a first transparent conductive oxide layer located on the semiconductor stack layer, wherein the first transparent conductive oxide layer has at least an opening and is in ohmic contact with the semiconductor stack layer; and a second transparent conductive oxide layer covering the first transparent conductive oxide layer, wherein the second transparent conductive oxide layer is filled into the opening.
The present application further discloses an optoelectronic element comprising a semiconductor stack layer; a first transparent conductive oxide layer located on the semiconductor stack layer, wherein the first transparent conductive oxide layer has at least an opening; and a second transparent conductive oxide layer covering the first transparent conductive oxide layer, wherein the second transparent conductive oxide layer is filled into the opening and in ohmic contact with the semiconductor stack layer.
The present application further discloses an optoelectronic element comprising a semiconductor stack layer comprising a first surface and a second surface; a first transparent conductive oxide layer formed on the first surface of the semiconductor stack layer, wherein the first transparent conductive oxide layer comprises at least an opening exposing the first surface of the semiconductor stack layer; and a second transparent conductive oxide layer filled into the opening and covering the first transparent conductive oxide layer; wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer are comprised of a material selected from the group consisting of indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), aluminum tin oxide (ATO), aluminum zinc oxide (AZO), and zinc oxide (ZnO), and the first transparent conductive oxide layer and the second transparent conductive oxide layer have the same constituent material with different refractive indexes.
The present application further discloses an optoelectronic element comprising a semiconductor stack layer comprising a first surface and a second surface; a first transparent conductive oxide layer formed on the first surface and having at least one opening; and a second transparent conductive oxide layer covering on the first transparent conductive oxide layer and filled into the opening, wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer are composed of the same materials but in different composition ratios.
The present application further discloses an optoelectronic element, comprising a semiconductor stack layer comprising a first surface and a second surface; a first transparent conductive oxide layer formed on the first surface of the semiconductor stack layer, wherein the first transparent conductive oxide layer comprises at least an opening exposing the first surface of the semiconductor stack layer; and a second transparent conductive oxide layer filled into the opening and covering the first transparent conductive oxide layer; wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer are comprised of a material selected from the group consisting of indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), aluminum tin oxide (ATO), aluminum zinc oxide (AZO), and zinc oxide (ZnO), and the first transparent conductive oxide layer and the second transparent conductive oxide layer have the same constituent material with different grain sizes.
One objective of the present application is to provide an optoelectronic element comprising a first transparent conductive oxide layer having at least an opening to increase the lighting efficiency of the optoelectronic element. The first transparent conductive oxide layer can also form a structure having a plurality of openings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic structure diagram of a conventional optoelectronic element.
FIG. 2 is a schematic structure diagram of a conventional optoelectronic device.
FIG. 3 is a schematic structure diagram of an embodiment of the present application.
FIGS. 4A to 4D are fabrication flow diagrams of an embodiment of the present application.
FIG. 5 is a schematic structure diagram of another embodiment of the present application.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 3 is a schematic structure diagram of an embodiment of the present application. As shown in FIG. 3 , an optoelectronic element 300 includes a semiconductor stack layer 30 having a first principal surface 302 and a second principal surface 304 ; a first transparent conductive oxide layer 32 located on the first principal surface 302 or second principal surface 304 ; in the present embodiment, the first transparent conductive oxide layer 32 is located on the first principal surface 302 ; and a second transparent conductive oxide layer 34 covering the first transparent conductive oxide layer 32 to form a surface substantially parallel to the first principal surface 302 or the second principal surface 304 , wherein the first transparent conductive oxide layer 32 further includes a plurality of openings 320 thereon, and the second transparent conductive oxide layer 34 is filled into the openings 320 of the first transparent conductive oxide layer 32 and in contact with the semiconductor layer 30 , wherein the first transparent conductive oxide layer 32 or the second transparent conductive oxide layer 34 can form an ohmic contact with the semiconductor stack layer 30 . In the present embodiment, the first transparent conductive oxide layer 32 forms an ohmic contact with the semiconductor stack layer 30 for an electrical connection, and where the second transparent conductive oxide layer 34 in contact with the semiconductor layer 30 dose not form an ohmic contact but a schottky contact.
Additionally, the optoelectronic element 300 further includes a substrate 36 located under the second principal surface 304 , and an electrode 38 located on the second transparent conductive oxide layer 34 , wherein the electrode 38 is located directly above the opening 320 of the first transparent conductive oxide layer 32 .
The semiconductor stack layer 30 from top to bottom can include a first conductive type semiconductor layer 306 , an active layer 308 , and a second conductive type semiconductor layer 310 . The material of the semiconductor stack layer 30 is selected from the III-V group materials, for example, the semiconductor materials contain Al, Ga, In, N, P or As, such as GaN series, AlGaInP series or GaAs series; and the materials of the first transparent conductive oxide layer 32 and the second transparent conductive oxide layer 34 can be ITO, InO, SnO, CTO, ATO, AZO, or ZnO, wherein the grain size or the reflective index of the first transparent conductive oxide layer 32 differs from that of the second transparent conductive oxide layer 34 . The first transparent conductive oxide layer 32 and the second transparent conductive oxide layer 34 are composed of different materials, or are composed of the same materials but in different composition ratios. The first transparent conductive oxide layer 32 and the second transparent conductive oxide layer 34 can form an ohmic contact therebetween to promote current spreading effect.
Additionally, the first transparent conductive oxide layer 32 has a plurality of openings 320 , and the top surface of the second transparent conductive oxide layer 34 that fills into the opening 320 and covers the first transparent conductive oxide layer 32 can be a flat surface substantially parallel to the first principal surface 302 or the second principal surface 304 , or a roughing surface (not shown) to reduce the probability of total reflection for the light emitted from the optoelectronic element 300 , therefore raising the light extraction efficiency of the optoelectronic element 300 .
Moreover, in the present embodiment, the first transparent conductive oxide layer 32 forms an ohmic contact with the semiconductor stack layer 30 for forming an electrical connection, and the contact between the second transparent conductive oxide layer 34 and the semiconductor layer 30 is not ohmic but such as a schottky contact. When flowing into the optoelectronic element 300 , the current is conducted into the second transparent conductive oxide layer 34 via the electrode 38 . However, the contact between the second transparent conductive oxide layer 34 and the semiconductor stack layer 30 is not ohmic, and the contact between the first transparent conductive oxide layer 32 and the semiconductor stack layer 30 is ohmic, so the current flowing through the second transparent conductive oxide layer 34 can be conducted into the semiconductor stack layer 30 via the first transparent conductive oxide layer 32 . If the electrode 38 of the optoelectronic element 300 is located directly above the opening 320 of the first transparent conductive oxide layer 32 , the current spreading effect can be much improved, therefore the light-emitting efficiency of the optoelectronic element 300 in enhanced.
FIG. 4A to FIG. 4D are the fabrication flow diagram of the optoelectronic element 300 . As shown in FIG. 4A , a substrate 36 is firstly provided, and a semiconductor stack layer 30 is formed on the substrate 36 by Metal Organic Chemical Vapor Deposition (MOCVD) or Liquid Phase Epitaxy (LPE), wherein the semiconductor stack layer 30 includes a first conductive type semiconductor layer 306 , an active layer 308 , and a second conductive type semiconductor layer 310 . Then, as shown in FIG. 4B , a first transparent conductive oxide layer 32 formed on the semiconductor stack layer 30 by e-beam vapor deposition or sputtering deposition, and a plurality of openings 320 exposing the semiconductor stack layer 30 are formed on the first transparent conductive oxide layer 32 by photo-lithography etching technology, wherein the an ohmic contact is formed at the interface between the first transparent conductive oxide layer 32 and the semiconductor stack layer 30 . Then, as shown in FIG. 4C , a second transparent conductive oxide layer 34 is formed on the first transparent conductive oxide layer 32 by applying e-beam vapor deposition or sputtering deposition, wherein the second transparent conductive oxide layer 34 covers the first transparent conductive oxide layer 32 and fills into the pluralities openings 320 thereof and is in contact with the semiconductor stack layer 30 . Besides, by adjusting the forming method or fabrication process condition, such as controlling gas species or flow rate, reactor temperature or pressure, and/or annealing temperature or time, the second transparent conductive oxide layer 34 does not form an ohmic contact with the semiconductor stack layer 30 . In the present embodiment, the second transparent conductive oxide layer 34 is positioned in an environment having sufficient nitrogen and is partially processed by laser annealing, so the second transparent conductive oxide layer 34 does not form an ohmic contact with the semiconductor stack layer 30 . Finally, as shown in FIG. 4D , a roughing structure is formed on the top surface of the second transparent conductive oxide layer 34 by etching, and an electrode 38 is formed on the second transparent conductive oxide layer 34 , wherein the electrode 38 is located opposite to the opening 320 of the first transparent conductive oxide layer 32 , and the optoelectronic element 300 is formed accordingly.
FIG. 5 is a schematic structure diagram of another embodiment of the present application. As shown in FIG. 5 , an optoelectronic element 500 at least includes a semiconductor stack layer 50 , a first transparent conductive oxide layer 52 located on the bottom surface of the semiconductor stack layer 50 , and a second transparent conductive oxide layer 54 located under the first transparent conductive oxide layer 52 , wherein the semiconductor stack layer 50 at least includes a first conductive type semiconductor layer 502 , an active layer 504 , and a second conductive type semiconductor layer 506 . The first transparent conductive oxide layer 52 has a plurality of openings 520 , the second transparent conductive oxide layer 54 is filled into the openings 520 and is in contact with the semiconductor stack layer 50 , so there is no ohmic contact formed between the first transparent conductive oxide layer 52 and the semiconductor stack layer 50 but non-ohmic contact like schottky contact, and there is ohmic contact formed between the second transparent conductive oxide layer 54 and the semiconductor stack layer 50 .
The material of the semiconductor stack layer 50 can be III-V group semiconductor materials, containing Al, Ga, In, N, P or As, such as GaN series, AlGaInP series or GaAs series, and the materials of the first transparent conductive oxide layer 52 and the second transparent conductive oxide layer 54 can be ITO, InO, SnO, CTO, ATO, AZO, or ZnO, wherein the grain size or the reflective index of the first transparent conductive oxide layer 52 differs from that of the second transparent conductive oxide layer 54 . The first transparent conductive oxide layer 52 and the second transparent conductive oxide layer 54 have different composing materials, or have the same composing materials but different composing ratio. The first transparent conductive oxide layer 52 and the second transparent conductive oxide layer 54 can form an ohmic contact therebetween to promote current spreading effect.
Additionally, the optoelectronic element 500 further includes a conductive adhesion layer 56 located under the second transparent conductive oxide layer 54 , a substrate 58 located under the conductive adhesion layer 56 , and an electrode 60 located on the semiconductor stack layer 50 , wherein the electrode 60 is located directly above the first transparent conductive oxide layer 52 . The interface of the first transparent conductive oxide layer 52 and the semiconductor stack layer 50 dose not form an ohmic contact, so when the current flows into the semiconductor stack layer 50 from the electrode 60 , it flows to the conductive adhesion layer 56 and the substrate 58 via the second transparent conductive oxide layer 54 filled into the openings 520 . Because the electrode 60 is located directly above the first transparent conductive oxide layer 52 , most current does not directly flow through the active layer 504 under the electrode 60 , therefore the current spreads effectively. | An optoelectronic element comprises a semiconductor stack layer comprising a first surface and a second surface; a first transparent conductive oxide layer formed on the first surface of the semiconductor stack layer, wherein the first transparent conductive oxide layer comprises at least an opening exposing the first surface of the semiconductor stack layer; and a second transparent conductive oxide layer filled into the opening and covering the first transparent conductive oxide layer; wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer are comprised of a material selected from the group consisting of indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), aluminum tin oxide (ATO), aluminum zinc oxide (AZO), and zinc oxide (ZnO), and the first transparent conductive oxide layer and the second transparent conductive oxide layer have the same constituent material with different refractive indexes. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. No. 60/546,685, entitled “Oil Free Head Valve for Pneumatic Nailers and Staplers,” filed Feb. 20, 2004 which is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention generally relates to the field of power tools, and particularly to a head valve assembly for pneumatic fasteners, such as pneumatic nailers and staplers.
BACKGROUND OF THE INVENTION
[0003] Pneumatic power tools are commonly employed in a variety of work places in order to accomplish various tasks. Typical pneumatic power tools include pneumatic fasteners, such as pneumatic nailers and pneumatic staplers. A typical system within a pnemutic fastener generates the desired hammering force by employing compressed air (typically supplied by a separate air compressor), a valve assembly including a valve plunger, and a piston assembly including a sliding piston that drives a long blade. In such system, the piston is forced downward when the air pressure above the piston head is greater than below it. Moreover, the piston is forced into an “up” position when the air pressure below the piston is greater than above it. In addition, a trigger assembly is employed to allow a user to control the actuation of the pneumatic fastener.
[0004] In use, the pneumatic fastener is actuated by a user activating the trigger assembly. Upon actuation, the trigger assembly closes the trigger valve while opening a passageway to the atmosphere as such compressed air is prevented from flowing above the valve plunger whereby pressure beneath the plunger is greater than pressure above the plunger. This configuration causes the valve plunger to rise up and compressed air to travel to the piston head. The piston and the blade are then driven downward by the compressed air causing a fastener (e.g. a nail or staple) to be propelled from the chamber. The downward sliding of the piston, in turn, channels the air inside the cylinder through a series of holes into a return air chamber. When a user then releases the trigger assembly, the plunger is pushed back into place by the compressed air and air flow to the piston head is blocked. In the absence of downward pressure, the piston head is also pushed back up by the compressed air in the return air chamber. As a result, the air above the piston head is forced out of the gun and into the atmosphere.
[0005] Although the standard pneumatic fastener, such as a nailer, works well for driving even thick nails through hard material such fasteners are disadvantageous in many respects. First, the standard pneumatic fastener typically employs functional features for controlling and directing air flow which involve expensive and time consuming manufacturing processes and result in decreased performance characteristics. For example, many pneumatic fasteners require a cross hole to be drilled and plugged through an outer cap or an angled hole to be drilled through such cap in order to get supply air from the air source, through the outer cap and to the back side of the valve piston chamber. One disadvantage associated with this design is possible significant increases in manufacturing costs, which in turn may be passed onto the consumer. An additional disadvantage associated with such configuration is that employment of machined holes provide rough surfaces (e.g. edges) over which the air must travel. The rough surfaces may increase air flow turbulence/friction thereby reducing the efficiency of air flow travel and possibly decreasing the efficiency of the pneumatic fastener. Current solutions to overcome increased friction typically involve the application of a lubricant to the rough surfaces. Utilization of such lubricants may increase the cost of operating pneumatic fasteners while also possibly simultaneously resulting in decreased productivity as the pneumatic fasteners must halt operation in order to have the lubricant provided. In addition, the aforementioned disadvantage is continuous for the lubricant has a limited useful lifespan and must be continuously replaced to assist in smoothing the surfaces over which the air must travel.
[0006] Therefore, it would be desirable to provide a pneumatic fastener which requires neither the machining of the outer cap to establish air flow patterns nor application of a lubricant to prevent increases in air flow friction.
SUMMARY OF THE INVENTION
[0007] Accordingly, in a first aspect of the present invention a head valve assembly for a pneumatic fastener including a piston assembly reciprocated within a cylinder assembly for driving a fastener and a housing having an end cap for at least partially enclosing the head valve assembly is provided. In an exemplary embodiment, the head valve assembly includes a valve piston for causing supply pressure to be ported to the piston assembly for moving the piston assembly within the cylinder assembly from a non-actuated position to an actuated position for driving the fastener. Further, an inner cap is disposed within the end cap around the valve piston. The inner cap includes an inlet port for porting pressure to the valve piston. In addition, a main seal is coupled to the valve piston for sealing the cylinder assembly from supply pressure while pressure is ported to the valve piston by the inner cap for holding the piston assembly in the non-actuated position. The main seal seals pressure ported to the valve piston by the inner cap from supply pressure ported to the piston assembly.
[0008] In specific embodiments of the instant head valve assembly, the inner cap may further include an exhaust port for porting exhaust from the head valve assembly. Further, the inner cap may be formed of a lubricious plastic. In additional embodiments, the main seal includes a lip seal for forming a seal with the inner cap and may provide shock absorption to the piston assembly. In further embodiments, the main seal may be coupled to the valve piston by a snap-lock mechanism. In such embodiment, the main seal may include a plurality of legs while the valve piston may include a plurality of leg receivers for coupling the main seal to the valve piston. For example, the snap-lock assembly comprises a plurality of legs extending from the main seal and a plurality of leg receivers disposed in an inner surface of the valve piston, each of the plurality of legs being received in a corresponding one of the plurality of leg receivers for coupling the main seal to the valve piston. In such embodiment, the piston assembly may include a projection, the plurality of legs for receiving and retaining the projection upon return of the piston assembly from the actuated position to the non-actuated position. In further exemplary embodiments, a lip seal is disposed between the valve piston and the inner cap.
[0009] In additional specific embodiments of the head valve assembly, a compression spring may be employed for biasing the valve piston toward the piston assembly and causing the main seal to seal the cylinder assembly from supply pressure. For instance, the compression spring may trap the plurality of legs for preventing the main seal from separating from the piston valve by the piston assembly as the piston assembly moves from the non-actuated position to the actuated position. It is contemplated that the present head valve assembly may be coupled to various types of pneumatic fasteners including a pneumatic nailer and a pneumatic stapler.
[0010] In an additional exemplary aspect of the present invention, a fastener device including dual actuation mode capability is disclosed. The apparatus of the present invention permits a user to select between a contact actuation mode in-which a user pulls or draws a trigger and actuation of the fastener device is initiated by a contact safety assembly and a sequential actuation mode in-which the contact safety assembly is depressed first and the trigger initiates actuation of the fastening event. The fastener device includes a sliding contact safety assembly which is configured to reciprocate towards/away from a driver housing. The contact safety assembly includes a contact member for contacting a workpiece. A rotating rod is pivotally operable with respect to an intermediate linkage. A pivot pin may be attached to the intermediate linkage. The rotating rod may include a recess for receiving the pivot pin. The pivot pin is configured with a first shoulder or ledge and a second shoulder which is off-set from the first shoulder. The second shoulder is further away from an end of the rod, opposite the linkage, than the second shoulder. The rod may be rotated to orientate either the first or the second shoulders toward a trigger assembly. The trigger assembly is pivotally coupled, via a pivot pin, to the driver housing. Trigger assembly is constructed so that a portion of the trigger contacts with the selected shoulder on the rotating rod so that the rod acts a stop for the trigger. A trigger lever is preferably included for actuating a valve or the like for permitting compressed air (in the case of a pneumatic fastener) to enter a driver chamber for forcing a piston with a driver blade attached thereto to secure a fastener. A toggle switch may be included to engaged with the rod to allow for efficient rotation. Preferably, a toggle switch is configured to remain in a fixed position while the contact safety assembly slides.
[0011] In a further aspect, a depth adjustment system is included to permit varying the depth to which a fastener to be secured will be driven. In this aspect of the invention, a threaded thumb wheel is included to engage with a threaded portion of a pivot pin included on the intermediate linkage. A washer, biased into engagement with the thumb wheel, having a series of detents is included to secure the thumb wheel in the desired position along the pivot pin. The thumb wheel may be manipulated to increase or decrease the overall length of the contact safety system thereby varying the extent to which a fastener will be driven into a workpiece.
[0012] In a further exemplary aspect of the present invention, an adjustable handle exhaust assembly is provided. The adjustable handle exhaust assembly includes a base, which includes a base plate and a protrusion protruding from the base plate. The protrusion is centrally hollow and includes an inner surface and an outer surface. The base plate includes an inlet opening and an exhaust opening defined therethrough. The inlet opening is interconnected with a channel defined by the inner surface of the protrusion. A cap is coupled to and supported by the base and includes an exit opening. A quick connector coupler is positioned inside the channel defined by the inner surface of the protrusion. When coupled to a pneumatic fastener, the quick connector coupler is suitable for connecting to an air supply hose to input compressed air to the pneumatic fastener via the channel defined by the inner surface of the protrusion and the inlet opening, and exhaust from the pneumatic fastener may exit through the exhaust opening and the exit opening.
[0013] In a still further exemplary aspect of the present invention, a pneumatic fastener is provided. The pneumatic fastener includes a handle which includes an inlet channel and an outlet channel. An adjustable handle exhaust assembly is coupled to the handle for connecting to an air supply hose to input compressed air to the pneumatic fastener via the inlet channel and outputting exhaust of the pneumatic fastener via the outlet channel to outside. The adjustable handle exhaust assembly includes a base, a cap and a quick connector coupler. The base includes a base plate and a protrusion protruding from the base plate. The protrusion is centrally hollow and includes an inner surface and an outer surface. The base plate includes an inlet opening and an exhaust opening defined therethrough. The inlet opening is interconnected with a channel defined by the inner surface of the protrusion. The cap is coupled to and supported by the base and includes an exit opening. The quick connector coupler is positioned inside the channel defined by the inner surface of the protrusion. The quick connector coupler is suitable for connecting to the air supply hose to input the compressed air to the pneumatic fastener via the channel defined by the inner surface of the protrusion, the inlet opening, and the inlet channel, and the exhaust may exit through the outlet channel, the exhaust opening and the exit opening.
[0014] In another exemplary aspect of the present invention, a handle for a pneumatic fastener is provided. The handle includes an inlet channel for inputting compressed air into the pneumatic fastener, an outlet channel for outputting exhaust of the pneumatic fastener to outside, and an adjustable handle exhaust assembly coupled to the handle. The adjustable handle exhaust assembly includes a base, a cap, and a quick connector coupler. The base includes a base plate and a protrusion protruding from the base plate. The protrusion is centrally hollow and includes an inner surface and an outer surface. The base plate includes an inlet opening and an exhaust opening defined therethrough. The inlet opening is interconnected with a channel defined by the inner surface of the protrusion. The cap is coupled to and supported by the base and includes an exit opening. The quick connector coupler is positioned inside the channel defined by the inner surface of the protrusion. The quick connector coupler is suitable for connecting to an air supply hose to input the compressed air to the pneumatic fastener via the channel defined by the inner surface of the protrusion, the inlet opening, and the inlet channel, and the exhaust may exit through the outlet channel, the exhaust opening and the exit opening.
[0015] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures in which:
[0017] FIG. 1 is an illustration of a pneumatic fastener in accordance with an exemplary embodiment of the present invention;
[0018] FIG. 2 is an exploded view of the pneumatic fastener including a head valve assembly coupled with a piston assembly in accordance with an exemplary embodiment of the present invention;
[0019] FIG. 3 is a cut away view of a handle of the pneumatic fastener including a handle adapter coupled with an inlet channel and an exhaust channel coupled with a handle exhaust;
[0020] FIG. 4 is an illustration of the head valve assembly, the inner cap having an inner diameter coupled with a main seal and valve piston;
[0021] FIG. 5 is an illustration of the main seal connected with the valve piston through use of a snap lock mechanism;
[0022] FIG. 6 is an isometric illustration of the head valve assembly coupled with a housing and a cap of the pneumatic fastener, wherein the head valve assembly at least partially occupies a fully defined recessed area of the pneumatic fastener;
[0023] FIG. 7 is an isometric illustration of the housing including a housing inlet port and a housing outlet port;
[0024] FIG. 8 is a cross-sectional view of the pneumatic fastener including the head valve assembly coupled with the piston assembly and the housing, the main seal and valve piston shown in a down position relative to the inner cap of the head valve assembly, in accordance with an exemplary embodiment of the present invention;
[0025] FIG. 9 is an expanded cross-sectional view of the pneumatic fastener wherein the main seal and valve piston are shown in an up position relative to the inner cap of the head valve assembly;
[0026] FIG. 10 illustrates the head valve assembly of the present invention employing a diaphragm coupled with the inner diameter of the inner cap;
[0027] FIG. 11 is a partial side view illustration of a pneumatic fastener including a dual actuation mode assembly;
[0028] FIG. 12 is an exploded view of the contact safety illustrated in FIG. 11 ;
[0029] FIG. 13A is a cut-away side view of a dual actuation mode assembly;
[0030] FIG. 13B is a cut-away side view of the dual actuation mode assembly illustrating a rotating rod in contact actuation mode;
[0031] FIG. 13C is a cut-away side view of the dual actuation mode assembly illustrating a rotating rod in sequential actuation mode;
[0032] FIG. 14 is an illustration of an adjustable handle exhaust assembly for use with a pneumatic fastener; and
[0033] FIG. 15 is an exploded view of the adjustable handle exhaust assembly.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.
[0035] Referring now to FIG. 1 , an exemplary embodiment of a pneumatic fastener 100 in accordance with the present invention is provided. In the exemplary embodiment, the pneumatic fastener 100 includes a handle 102 having a first end 103 and a second end 105 . In the present embodiment, a housing 104 is coupled with the first end 103 of the handle 102 . The handle 102 further includes a handle adapter 156 , which enables the coupling of a compressed air supply to the pneumatic fastener 100 . In addition, a trigger assembly 108 for controlling the firing of the pneumatic fastener 100 may be coupled with the handle 102 , proximal to the first end 103 .
[0036] Referring now to FIG. 2 , in the exemplary embodiment the housing 104 defines a housing recessed area 125 within which a piston assembly including a cylinder 130 and a piston 134 may be mounted. The cylinder 130 is slidably coupled with the piston 134 which includes a piston projection 136 . It is understood that the piston 134 may operationally engage a driver blade for driving a fastener by providing force to the driver blade. The piston projection 136 , in the current embodiment, is enabled in a generally cylindrical shape. Alternatively, the piston projection 136 may be configured in various shapes, such as rectangular, spherical, and the like.
[0037] In an exemplary embodiment, the housing 104 includes a first end 107 and a second end 109 . The first end of the housing 107 may couple with various mechanical devices to enable the functionality of the nailer, such as a nose casting assembly, which may enable the operation of the driver blade. The second end 109 of the housing 104 includes a first housing fastening point 110 , a second housing fastening 111 , a third housing fastening point 112 , and a fourth housing fastening point 113 . In an advantageous embodiment, the fastening points allow the coupling of an outer cap 114 with the second end 109 of the housing 104 . It is understood that the outer cap 114 may be composed of various materials, such as aluminum, steel, plastic, and the like. The fastening points may enable the use of a variety of fasteners. Suitable fasteners may include a screw, bolt, clip, pin, and the like. In the current embodiment, the cap 114 includes a first cap fastening point 115 , a second cap fastening point 116 , a third cap fastening point 117 , and a fourth cap fastening point 118 . The cap fastening points align with the housing fastening points to enable the fasteners to engage with the housing 104 and the cap 114 thereby securely affixing their position relative to one another.
[0038] In the exemplary embodiment, the housing recessed area 125 is defined on one end by the first end 107 of the housing 104 and on the other end by the second end 109 of the housing 104 . The cap 114 further defines an outer cap recessed area 119 . When the cap 114 is coupled with the housing 104 , a fully defined recessed area 129 (as illustrated in FIG. 6 ), of the pneumatic fastener 100 is established. It is understood that various configurations of the housing 104 and the cap 114 may define variously configured recessed areas 129 . It is contemplated that the configurations of the housing 104 and the cap 114 may partially encompass the recessed area 129 . Further, the housing 104 and the cap 114 may be configured for aesthetic and/or functional purposes. For example, contouring may establish the housing 104 and the cap 114 with an advantageous appearance, which may also provide for increased functionality by providing a contoured grip region. Still further, grip regions may be established with material for grasping engagement by the hand of the user of the pneumatic fastener 100 , including soft grips and the like.
[0039] As illustrated in FIG. 2 , the housing 104 may further define an inlet (supply) port 121 and an outlet (exhaust) port 123 . The configuration of the housing inlet port 121 and the housing outlet port 123 may vary. In a preferred embodiment, the housing inlet port 121 is of a generally cylindrically shaped conduit extending through the housing 104 while the housing outlet port 123 is of a generally rectangularly shaped conduit extending through the housing 104 . It is understood that the shape and/or configuration of the housing inlet and outlet ports may be varied as contemplated by those of ordinary skill in the art. For instance, the diameter of the housing inlet port 121 may be increased or decreased to alter the characteristics of the supply pressure. As shown in FIG. 3 , the housing inlet port 121 acts as a conduit for the supply of compressed air coming through the inlet channel 126 via the handle adapter 156 connection. In addition, the housing outlet port 123 acts as a conduit for the air exhausted after the firing of the pneumatic fastener, directing the exhaust to the outlet channel 128 and then through a handle exhaust 158 of the handle 102 .
[0040] In further exemplary embodiments, as illustrated in FIG. 2 , the pneumatic fastener 100 includes a head valve assembly with an inner cap 150 for directing the flow of air to and from the piston 134 of the piston assembly of the fastener 100 . In an exemplary embodiment, a basket 132 is included within the inner cap 150 for stabilizing the piston 134 . In an alternative embodiment, the basket 132 is not included within the inner cap 150 , but directly seated upon the cylinder 130 .
[0041] In the present exemplary embodiment, the head valve assembly at least partially occupies the recessed area 129 . Further, a main seal 142 is adjustably coupled with an inner diameter 151 of the inner cap 150 . The main seal 142 is further coupled with the piston 134 and a valve piston 144 . In a preferred embodiment, the main seal 142 is seated upon the piston 134 . This coupling allows the main seal 142 to provide shock-absorption to the piston 134 of the pneumatic fastener 100 . The main seal 142 , in a preferred embodiment, may be composed of a urethane material. Alternative materials, such as other plastics, metals, and the like, may be employed as contemplated by those of skill in the art which include the desired durability. Additionally, in such advantageous embodiment, the valve piston 144 is composed of a plastic material. It is further preferred that the plastic be an acetal which includes compounds that are characterized by the groupig C(OR) 2 , such as Delrin®, a registered trademark owned by the E.I. du Pont de Nemours and Company. Such composition provides the valve piston 144 with a reduced frictional coefficient while still enabling a secure coupling with the main seal 142 .
[0042] As further illustrated in FIG. 2 , in an exemplary embodiment, an O-ring gasket 190 connects the top side 180 , of the inner cap 150 , with an inner wall 120 of the cap recessed area 119 of the aluminum cap 114 . The O-ring gasket 190 provides a seal between the aluminum cap 114 and the inner cap 150 . It is understood that the O-ring gasket 190 may enable various degrees of stretching and/or deflecting depending on the materials used to establish the O-ring gasket 190 . This seal assists in directing the air flow provided into and out of the head valve assembly 140 via the inner cap inlet conduit 182 and the inner cap outlet conduit 184 . In a preferred embodiment, the O-ring gasket 190 may nest in a groove established in the inner wall 120 of the aluminum cap 114 . In an alternative embodiment, the O-ring gasket 190 may nest in a groove established in the top side 180 of the inner cap 150 . It is further contemplated that the O-ring gasket 190 may be integrated with either the inner wall 120 of the aluminum cap 114 or the top side 180 of the inner cap 150 .
[0043] As illustrated in FIG.4 , the inner cap 150 is further comprised of an inner cap exhaust conduit 184 . The inner cap outlet conduit 184 directs the flow of exhausted air to the housing outlet port 123 , established in the second end 109 , of the housing 104 , which is connected to the exhaust channel 128 within the handle 102 . Thus, the exhausted air is removed from the head valve assembly 140 via the inner cap 150 .
[0044] It is contemplated that the coupling of the main seal 142 with the piston 134 may be accomplished in a variety of ways. For example, in an exemplary embodiment, the main seal 142 is coupled with the valve piston 144 via a snap lock mechanism. In an advantageous embodiment, as illustrated in FIGS. 4 and 5 , the snap lock mechanism is enabled by a first leg 160 , a second leg 162 , and a third leg 164 which are connected to the main seal 142 . In configuration, the legs 160 through 164 generally extend from the main seal 142 and include a tapered undercut on a flange included within each of the three legs. Further, on the end opposite the connection to the main seal 142 , each leg terminates in a tab, which generally extends from the leg. The legs are formed about a piston projection receiving point 166 . In the current embodiment, the piston projection receiving point 166 is an aperture, which extends through the main seal 142 .
[0045] As illustrated in FIG. 5 , in an exemplary embodiment, the legs 160 through 164 of the main seal 142 couple with a first leg receiver 172 , a second leg receiver 174 , and a third leg receiver 176 , respectively. In the present embodiment, the leg receivers are disposed within a valve piston inner diameter of the valve piston 144 . In a preferred embodiment, the three leg receivers are established by a ledge 171 . In such embodiment, the ledge 171 includes three grooves for receiving the three legs of the main seal 142 . In an alternative embodiment, the three leg receivers may be established as pockets disposed within the inner diameter of the valve piston 144 . The three leg receivers 172 through 176 are configured with a matching profile to that of the three legs 160 through 164 .
[0046] In operation, the three legs of the main seal 142 may be inserted within the three leg receivers of the valve piston 144 . Upon being fully inserted, the tabs formed at the terminus of each leg may snap into place with respect to the leg receivers. The snapping into place may be accomplished in a variety of manners. In the present example, the material composition and configuration of the legs provide the force which snaps the tabs into place. The tabs assist in securing the position of the main seal 142 relative to the valve piston 144 by coupling the tabs against the valve piston 144 . In alternative embodiments, the snap mechanism may be enabled as a spring loaded assembly and the like as contemplated by those of ordinary skill in the art. It is further contemplated that the main seal 142 and the valve piston 144 may be an integrated single unit.
[0047] In further exemplary embodiments, a secondary coupling of the valve piston 144 with the main seal 142 occurs via a tongue and groove assembly. The valve piston 144 includes a tongue member disposed about the circumference of a bottom edge of the valve piston 144 . In a corresponding circumferential position on the main seal 142 , a groove is established. Thus, when the main seal 142 is coupled with the valve piston 144 , via insertion of the plurality of legs into the plurality of leg receivers, the tongue is inserted within the groove to provide secondary coupling support. It is contemplated that the secondary coupling characteristics may be provided through various alternative mechanisms. For example, the secondary coupling may be established by employing a friction lock mechanism, a compression lock mechanism, a latch mechanism, and the like, without departing from the scope and spirit of the present invention.
[0048] As illustrated in FIG. 6 , in an exemplary embodiment, the piston projection receiving point 166 is configured to receive the piston projection 136 . Therefore, as the configuration of the piston projection 136 is altered so to may the piston projection receiving point 166 and the three legs 160 , 162 , and 164 be altered to accommodate this change. The three legs 160 through 164 , in a preferred embodiment, are enabled to trap and hold the piston projection 136 when extended through the piston projection receiving point 166 .
[0049] The securing of the piston projection 136 by the three legs may be accomplished using various mechanisms. In a preferred embodiment, the three legs serve as a piston catch by providing a friction fit for engaging against the piston projection 136 . Alternatively, the enabling of the piston catch may occur through the use of compression assemblies, ball joint assemblies, and the like. It is understood that the three legs trap and hold the piston projection 136 when the piston 134 is established in an “up” position (as illustrated in FIG. 9 ). It is further contemplated that the cylinder 130 may include a counter bore to further assist in maintaining the piston in the “up” position. The “up” position is the pre-fire position or the position the piston 134 returns to after the pneumatic fastener 100 has fired, using the compressed air to drive the piston 134 into a “down” position (as illustrated in FIG. 8 ). The “down” position provides the force for driving the driver blade through the nose casting, engaging with a nail located within the nose casting, and driving the nail into a surface against which the nose casting is set. The piston catch established by the present invention may provide increased efficiency by reducing any unwanted travel by the piston 134 towards the “down” position when the pneumatic fastener 100 is not being fired. For instance, when the pneumatic fastener 100 is set in a position to fire the user may tap the surface, inadvertently, being operated upon with the gun. This tap may result in the piston 134 traveling towards the “down” position. This travel may reduce the operational effectiveness of the pneumatic fastener 100 by limiting the range of travel of the piston 134 during firing of the gun 100 , thereby, limiting the force provided by the piston 134 in driving the fastener, such as the nail, by the pneumatic fastener 100 . This limited force may result in the fastener failing to reach the desired depth, such as by not recessing properly, which may have the effect of requiring additional time spent to accomplish a task. This may limit productivity and increase expenses associated with completing the task.
[0050] In an exemplary embodiment, as illustrated in FIGS. 8 and 9 , a compression spring 148 is coupled against a bumper seal 152 on one end and the three legs 160 , 162 , and 164 , snapped in position relative to the valve piston 144 , on the opposite end. In the exemplary embodiment, the compression spring 148 extends through a spring receiving point 181 (as shown in FIG. 4 ) of the inner cap 150 . In the current embodiment, as shown in FIG. 4 , the spring receiving point 181 is an aperture through a top side 180 of the inner cap 150 . The coupling against the three legs snapped into position relative to the valve piston 144 enables the compression spring 148 to “trap” the legs (as illustrated in FIG. 9 ), thereby, assisting in preventing the main seal 142 from being pulled away from the valve piston 144 by the piston 134 when fired.
[0051] The functionality of the compression spring 148 in combination with the snap fit of the main seal 142 with the valve piston 144 assists in enabling the main seal 142 to establish and maintain a seal between the supply pressure and the pressure behind the valve piston 144 . In the current embodiment, the main seal 142 includes a main lip seal 143 to further assist in providing the above mentioned functionality. The main lip seal 143 further enables the main seal 142 to slidably couple with the inner diameter 151 of the inner cap 150 . Thus, the main lip seal 143 enables the main seal 142 to travel within the inner cap 150 and maintain the seal between the supply pressure and the pressure behind the valve piston 144 . It is understood, that the travel of the main seal 142 translates into a travel of the valve piston 144 , within the inner cap 150 , and the compression or extension of the compression spring 148 . A secondary lip seal 146 is set upon the valve piston 144 . The secondary lip seal 146 is set on the side opposite the coupling of the main seal 142 against the valve piston 144 . The secondary lip seal 146 may assist in providing a seal between the valve piston 144 and the inner cap 150 .
[0052] It is contemplated that the inner cap 150 may be composed of various materials. For example, the inner cap 150 may be composed of Delrin®, a registered trademark owned by the E.I. du Pont de Nemours and Company. A composition including Delrin® is advantageous for Delrin® is an acetal which is a lubricious plastic providing a surface which may reduce the amount of turbulence/friction involved with the travel of the compressed air into or out of the head valve assembly 140 of the present invention. Further, the use of Delrin® for the valve piston 144 , as stated previously, may reduce the amount of turbulence/friction encountered by the valve piston 144 during travel of the valve piston 144 within the inner diameter 151 of the inner cap 150 . The materials used for the inner cap 150 may further comprise alternative plastics, Teflon® (a registered trademark of DuPont), silicone, and the like. While the present invention is enabled with the inner cap 150 , which directs the air flow into and out of the head valve assembly 140 without requiring lubricants to be added, it is contemplated that various lubricants may be used in conjunction with the present invention. Lubricants, such as Teflon® based lubricants, silicone based lubricants, and aluminum disulfide based lubricants may be employed without departing from the scope and spirit of the present invention.
[0053] In an alternative embodiment, the main seal 142 and valve piston 144 may be replaced by a diaphragm 198 , as illustrated in FIG. 10 . The diaphragm 198 provides the functionality of the main seal 142 coupled with the inner diameter 151 of the inner cap 150 , of the head valve assembly 140 . The diaphragm may also couple with the cylinder 130 , at least partially surrounding the cylinder 134 . The diaphragm may be composed of various materials, which provide various degrees of stretching and/or deflecting of the diaphragm. This stretching and/or deflecting may translate into movement by the diaphragm 198 within the inner diameter 151 . As previously stated, this may further translate into the extension and/or compression of the compression spring 148 . It is still further contemplated that the use of the diaphragm 198 may eliminate the need for the compression spring 148 . It is understood that the configuration of the diaphragm 198 may be altered to accommodate the needs of the manufacturer, consumer, or those of ordinary skill in the relevant art. It is further contemplated that the diaphragm 198 may be employed in conjunction with the main seal 142 and the valve piston 144 . The diaphragm 198 may couple with the main seal 142 and any stretching/deflecting of the diaphragm 198 within the inner diameter 151 of the inner cap 150 may translate into movement of the main seal 142 and valve piston 144 within the inner diameter 151 .
[0054] During use, compressed air travels through the inner cap 150 and into the head valve assembly 140 via an inner cap inlet conduit 182 . The inner cap inlet conduit 182 establishes an air flow pattern through the inner cap 150 from the inlet channel 126 of the handle 102 . The housing inlet port 121 , established on the second end 109 of the housing 104 , enables the compressed air being provided through the inlet channel 126 , to flow into the inner cap inlet conduit 182 . The compressed air supplied through the inner cap inlet conduit 182 enables the head valve assembly 140 to operate the pneumatic fastener 100 , i.e., the firing of the piston 134 to drive the fastener into a surface or work piece.
[0055] Referring to FIGS. 11-13C , a pneumatic fastener 1100 including a dual actuation mode assembly 1102 is discussed. Those of skill in the art will appreciate that while a pneumatic fastener is discussed, the principles of the present invention may equally apply to devices utilizing a combustion event or a detonation event to secure a fastener such as a nail, a staple, or the like. The dual actuation mode assembly 1102 permits user selection of the type of actuation the fastener device is to operate (e.g. in a contact fire mode or sequential actuation mode). In contact actuation mode, a user pulls (and holds) the trigger 1104 and subsequently the contact safety assembly 1106 is depressed or pushed inwardly toward a driver housing 1108 thereby activating a pneumatic valve 1109 for releasing compressed air to drive a piston and driver into contact with a nail or fastener disposed in the driver's path of travel. Subsequent fastening events, in contact actuation mode, may be initiated by movement of the contact safety towards the driver housing such as when the pneumatic fastener 1100 has been repositioned and pressed against a workpiece. In sequential fire mode, the contact safety assembly is depressed toward the driver housing and subsequently the trigger is pulled to initiate a fastening event (the driving of a nail, staple or the like).
[0056] With particular reference to FIGS. 11 and 12 , the pneumatic fastener 1100 includes the driver housing 1108 for housing a reciprocating piston including a driver blade attached thereto for driving a fastener disposed within the path of travel of the driver blade. A contact safety assembly 1106 is adjustably mounted to the driver housing 108 in order to permit the contact safety assembly to slide towards and away from to the driver housing/the nose 1110 of the driver housing. In various embodiments, the nose may be formed as a separate structure or may be integrally formed with the main portion of the driver housing 1108 . Preferably, the contact safety assembly 1106 is biased, such as by a main spring or the like, into a remote position or away from the nose 1110 of the driver housing. Biasing the contact safety assembly away from the main portion of the fastener permits the contact safety system to function as a lock-out mechanism so that the pneumatic fastener cannot actuate. Additionally, as described above, the contact safety assembly 1106 may be utilized to initiate a fastening event (in contact mode).
[0057] The contact safety assembly 1106 includes a contact pad 1114 or foot for contacting with a workpiece. Additionally, a no-mar tip may be releasably connected to the contact pad for preventing marring of the workpiece, if the contact pad is formed of metal or includes a serrated edge for engaging a workpiece (such as in a framing nailer). For example, the contact pad 1114 may be shaped so as to translate or slide along the nose 1110 of the driver housing 1108 . In the present embodiment, the contact pad 1114 is generally shaped as a hollow cylindrical structure for sliding along the generally cylindrical nose. An intermediate linkage 1116 is coupled to the contact pad 1114 to generally position a cylindrical rod 1118 along the driver housing 1108 . For example, the movement of the intermediate linkage may permit the cylindrical rod 1118 to be variously positioned with respect to the driver housing 1108 and thus, a trigger assembly which is 1104 pivotally mounted to the driver housing 1108 and/or a handle 1120 fixedly secured to the driver housing 1108 . In the current embodiment, the intermediate linkage 1116 is secured via a fastener to the contact pad 1114 . In further embodiments, the contact pad and linkage may be unitary. In the present example, the intermediate linkage is constructed in a general L-shape to position the rod 1118 adjacent the trigger (i.e., towards the handle 1120 ). Additionally, the intermediate linkage may be constructed so as to generally conform to the driver housing, to avoid other pneumatic fastener components, i.e, avoid fastener magazine components, for aesthetic purposes or the like. Moreover, in the present instance, the intermediate linkage 1116 includes a pivot pin 1122 coupled to an end of the linakge 1116 . The pivot pin 1122 may be secured via a fastener, a friction fit or unitarily formed with the intermediate linkage. In the present embodiment, the pivot pin 1122 is received in an aperture defined in a tab which extends generally perpendicular to a leg of the generally L-shaped linkage. A portion of the pivot pin 1122 may be received in a corresponding cylindrical recess formed in the rod 1118 for at least partially supporting/pivotally connecting the rod 1118 to the intermediate linkage via the pivot pin 1122 .
[0058] Referring to FIGS. 12 and 13 A, in an additional aspect of the present invention, the contact safety assembly 1106 includes an optional depth of drive or recess adjustment capability. A depth adjustment system permits a user to select to what extent the fastener is to be driven into the workpiece via selecting the extent to which the contact safety extends towards/away from the driver housing. Those of skill in the art will appreciate that a variety of factors will influence the depth to which a fastener will be driven. For example, a user may wish to leave the head of a nail above the surface of the workpiece (i.e. leave the nail proud) or may select to recess the nail head into the workpiece such that putty or filler may be filled into the recess thereby covering over the nail head (e.g., when building cabinetry or the like). In the present instance, the pivot pin 1122 includes a threaded portion 1124 or section for threading with a thumb wheel 1126 . A thumb wheel 1126 includes a corresponding aperture having a threaded portion 1130 such that the thumb wheel 1126 may travel along the threaded length of the pivot pin 1122 . The thumb wheel thereby may extend the overall length of the contact safety assembly and thus, vary the depth to which a fastener may be driven through interaction with the pneumatic valve 1109 for controlling the flow of compressed air into the driver cylinder. In the foregoing example, the thumb wheel 1126 may frictionally interconnect with a washer 1128 , disposed between the thumb wheel 1126 and a lip/flange 1134 included on the rod, via a series of rib/grooves, detents and protrusions or the like. It is to be appreciated that the rod 1118 is permitted to freely pivot (e.g., not in threaded engagement) about the pivot pin 1122 . For example, the rod 1118 and thus, the washer 1128 may be biased such as via a spring 1132 towards or into engagement with the thumb wheel 1126 . Preferably, the washer 1128 may be geometrically shaped or include protrusions such that the washer 1128 does not rotate with the thumb wheel 1126 , e.g., remains in a fixed orientation with respect to the driver housing and/or a secondary housing or contact safety housing 1136 coupled to the driver housing for at least partially encompassing at least a portion of the contact safety assembly. The series of protrusions/detents may act to retain the thumb wheel 1126 in a desired position along the pivot pin 1122 . Those of skill in the art will appreciate that the depth adjustment mechanism may be formed with a threaded projection in threaded connection with an end of a rod so as to effectively extend/retract the overall length of the rod. In the previous example, the projection is received in a recess formed in an intermediate linkage such as a tab included on an end of the linkage. For example, a rod may include a threaded portion along which a thumb wheel is in threaded engagement while the terminal portion of the rod is inserted in an aperture in an intermediate linkage.
[0059] In further embodiments, a depth of drive mechanism may be disposed between the contact pad 1114 and an intermediate linkage 1116 . Additionally, if a depth of drive or recess adjustment is not desired, the rod 1118 may extend into a recess or aperture included in a tab extending from an end of an intermediate linkage. In still further embodiments, a partially threaded pivot pin may be threaded into an aperture in the intermediate linkage and function as a pivot pin for the rod 1118 . Alternatively, a rod may include an extension which may be received in an aperture in the intermediate linkage for achieving substantially the same functionality.
[0060] With particular reference to FIGS. 12 and 13 A-C, the rod 1118 includes a first shoulder 1146 and a second shoulder 1148 . The first and the second shoulders are formed at offset distances along the length of the rod 1118 such that the orientation of a trigger 1152 and thus, a trigger lever 1142 pivotally coupled via a trigger lever pivot pin 1140 to the trigger may be varied. For example, the orientation/lateral position of the trigger lever 1142 permits selecting contact actuation mode (as illustrated in FIG. 13B ) when the first shoulder 1146 is orientated or rotated towards the trigger 1152 . While sequential actuation (as observed in FIG. 13C ) 1148 is achieved when a second shoulder which is further from the terminal end of the rod 1118 than the first shoulder 1146 is orientated or rotated towards the trigger 1152 . The particular actuation mode selected (i.e., contact actuation or sequential actuation) is determined by the change in orientation/lateral position of the trigger 1152 /trigger lever 1142 as the trigger assembly 1104 pivots about a trigger pivot pin 1156 and the selected shoulder contacts the trigger 1152 . For example, as the trigger 1152 pivots about the trigger pivot pin 1156 and contacts with the select shoulder, included on the rod, such that the shoulder acts as a stop against which the trigger 1152 is positioned. Those of skill in the art will appreciate that the interface of the rod/trigger is off-centered from the trigger pivot pin 1156 thereby varying the point (along the trigger lever 1142 ) at which the valve 1109 will contact the trigger lever 1142 due to the relative orientation/position of the trigger lever 1142 . In further embodiments, the trigger lever 1142 /trigger 1152 is biased away from the pneumatic valve 1109 by a spring 1154 or the like such that a user is required to overcome the biasing force to activate the valve 1109 . In the present embodiment, a central cylindrical projection extends beyond the first and the second shoulders 1146 and 1148 , respectively. In this instance, the trigger lever and trigger, such as the lipped portion of the trigger for engaging a shoulder, may include a curved recess to permit passage of the projection. The trigger lever 1142 may be configured to engage with the rod 1118 so as to prevent a repeated fastening event when sequential actuation or firing mode is selected. In further instances, the first and the second shoulders may be formed by milling flattened portions into a rod. Preferably, the shoulders are arranged at 180° (one hundred eighty degrees) from each other to permit sufficient engagement of the trigger and the selected shoulder.
[0061] With continued reference to FIGS. 11-13C , orientation of the rod 1118 may be achieved by rotating the rod 1118 such that a selected shoulder (the first shoulder 1146 or the second shoulder 1148 ) is aligned with a lip included on the trigger 1152 . A toggle lever or switch 1138 is coupled to the rod 1118 . In the present embodiment, the toggle switch 1138 is positioned below the trigger 1152 (with respect to the handle 1120 ) in order to permit a user to rotate the rod 1118 and thus, vary the pneumatic fastener's actuation mode by utilizing his/her forefinger and thumb. This positioning is additionally advantageous as a user may efficiently select between actuation modes without the complexity previously experienced. In the foregoing manner, a user may select between actuation modes more frequently thereby increasing efficiency over systems which require complex, time consuming manipulation. Preferably, the toggle switch defines an aperture through which the rod 1118 passes. In the present embodiment, a protrusion 1139 is formed by the toggle switch for extending into a keyway or channel extending longitudinally along at least a portion of the rod. In further embodiments, a setscrew may be utilized to accomplish this function. Those of skill in the art will appreciate a variety of mechanical interconnect systems may be implemented to achieve this function. For example, a portion of the rod may have a hexagonal cross section while a toggle switch includes a hexagonal aperture, a portion of the rod may be milled off or have a flattened portion or the like. Inclusion of a keyway or the like structure permits the toggle switch to remain in a fixed position (held in place via the contact safety housing 1136 ) with respect to the contact safety housing 1136 /the driver housing 1108 while the rod is permitted to variously position along the driver housing. Those of skill in the art will appreciate that the toggle may be fixedly secured to the rod as well so that the toggle switch travels with the rod 1118 as the contact safety assembly 1106 is manipulated generally along the driver housing.
[0062] In further examples, the toggle switch 1138 may include a detent for engaging with the contact safety cover in order to frictionally secure the toggle switch in a desired orientation (i.e. contact actuation or sequential fire). Moreover, the toggle switch may include a cam shaped outer surface for frictionally engaging the contact safety housing to retain the toggle in a desired orientation. For example, a detent and/or cam surface may be included to secure the toggle switch in sequential fire mode. Those of skill in the art will appreciate that the lever portion of the toggle may act as an indicator or indicia of the selected actuation mode to permit ready recognition. Additional symbols or markings may be included on the driver housing, the contact safety housing or provided as an adhered label to one of the housing to alert the user as to the mode selected. Preferably, the toggle switch is orientated at 90° (ninety degrees) or perpendicular to a main axis of the trigger so that the selected contact mode is readily observed. For example, the toggle lever may be orientated approximately 180° (one hundred eighty degrees) when disposed in contact actuation mode than when disposed in sequential actuation mode.
[0063] Referring now to FIGS. 14 and 15 , an additional embodiment of the present invention is illustrated wherein an adjustable handle exhaust assembly 1400 (see FIGS. 14 and 15 ) is provided. Such assembly 1400 may be coupled to a second end of a handle of a pneumatic fastener, such as a pneumatic nailer, to replace the handle exhaust 158 and handle adapter 156 as illustrated in FIG. 3 . The adjustable handle exhaust assembly 1400 may be used to input compressed air into the inlet channel 126 and may enable an operator to direct the flow of exhaust coming from the outlet channel 128 in a desired direction (e.g., away from the operator). The exhaust assembly 1400 includes a base 1402 , which includes a base plate 1404 and a cylindrical and centrally hollow protrusion 1406 protruding from and normal to the base plate 1404 . Preferably, the base plate 1404 includes an inlet opening defined therethrough and includes a first portion 1408 and a second portion 1410 . Both portions 1408 , 1410 have a circular shape and are attached to each other. The first portion 1408 is smaller than the second portion 1410 . That is, the diameter of the first portion 1408 is smaller than the diameter of the second portion 1410 so that a perimeter 1412 of the second portion 1410 is exposed for supporting a cap 1414 . The base plate 1404 includes a plurality of openings 1416 and an exhaust opening 1418 defined therethrough. A plurality of bolts 1420 may be inserted into the corresponding plurality of openings 1416 to securely couple the base 1402 to the second end 105 of the handle 102 of the pneumatic fastener 100 . The protrusion 1406 includes a threaded inner surface defining a channel for receiving a quick connector coupler 1422 and a partially threaded outer surface for receiving a compression ring 1426 . The channel defined by the threaded inner surface of the protrusion 1406 is interconnected with the inlet opening of the base plate 1404 . The cap 1414 may be made of metal, plastic, rubber, or the like. The cap 1414 includes an exit opening 1424 on its outer surface 1430 for letting the exhaust air exit the pneumatic fastener 100 . Preferably, the cap 1414 is donut-shaped with a central hole 1428 defined therein. The cap 1414 is placed on top of the base 1402 so that the protrusion 1406 protrudes from the central hole 1428 and the cap 1414 is supported by the perimeter 1412 of the second portion 1410 . Preferably, the cap 1414 is securely coupled to the base 1402 by the compression ring 1426 fastened on the partially threaded outer surface of the protrusion 1406 so that the exhaust inside the cap 1414 may exit to outside through the exit opening 1424 . The cap 1414 may be easily rotated to change the position of the exit opening 1424 whereby exhaust air exiting the exit opening 1424 can be directed in a desired direction (e.g., away from an operator).
[0064] The adjustable handle exhaust assembly 1400 may be securely coupled to the second end 105 of the handle 102 of the pneumatic fastener 100 by the bolts 1420 to replace the handle adapter 156 and the handle exhaust 158 . Preferably, the inlet opening of the base plate 1404 is interconnected with the inlet channel 126 , and the exhaust opening 1418 is interconnected with the outlet channel 102 . The quick connector coupler 1422 is connected to an air supply hose for supplying compressed air to the pneumatic fastener 100 . The compressed air flows from the air supply hose into the inlet channel 126 , via the quick connector coupler 1422 , the channel defined by the threaded inner surface of the protrusion 1406 , and the inlet opening of the base plate 1404 . The exhaust in the outlet channel 128 flows into the cap 1414 via the exhaust opening 1418 and exits the cap 1414 via the exit opening 1424 . An operator may rotate the cap 1414 easily to change the position of the exit opening 1424 so that the exhaust air exiting the exit opening 1424 is directed in a desired direction (e.g., away from the operator).
[0065] In a further exemplary embodiment directed to the present invention, a method of manufacturing a pneumatic fastener, such as the pneumatic fastener 100 , is provided. In a first step a housing including a piston assembly is provided. The housing may be of various configurations to support the functional operation of the pneumatic fastener and address aesthetic and/or ergonometric considerations. The housing is further provided with a housing inlet port and a housing exhaust port. The next step involves positioning a handle, including a handle adapter for receiving compressed air and a handle exhaust for exhausting the compressed air, to be coupled with the housing. The handle including an inlet channel coupled with the handle adapter and an outlet channel coupled with the handle exhaust. The inlet channel is further coupled with the housing inlet port and the outlet channel is further coupled with the housing exhaust port. Next, a head valve assembly including an inner cap of the present invention, is established in operational connection with the piston assembly. The inner cap further includes an inner cap inlet conduit which couples with the housing inlet port and an inner cap exhaust conduit which couples with the housing exhaust port. An outer cap is then fastened to the housing, the outer cap at least partially encompassing the head valve assembly and coupling with the inner cap.
[0066] It is contemplated that the method manufacturing may further include the establishment of a groove into the outer cap. The groove being enabled to receive an O-ring gasket and for providing a seal between the outer cap and the inner cap. In an alternative embodiment, the method of manufacturing may include the establishment of a groove in the inner cap for receiving an O-ring gasket and establishing a seal between the outer cap and the inner cap.
[0067] It is understood that the specific order or hierarchy of steps in the methods disclosed are examples of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the method can be rearranged while remaining within the scope and spirit of the present invention.
[0068] It is believed that the present invention and many of its attendant advantages will be understood by the forgoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof. Further, it is to be understood that the claims included below are merely exemplary of the present invention and are not intended to limit the scope of coverage which has been enabled by the written description. | The present invention provides a head valve assembly for a pneumatic fastener including a piston assembly reciprocated within a cylinder assembly for driving a fastener and a housing having an end cap for at least partially enclosing the head valve assembly. The head valve assembly includes a valve piston for causing supply pressure to be ported to the piston assembly for moving the piston assembly within the cylinder assembly from a non-actuated position to an actuated position for driving the fastener. Further, an inner cap is disposed within the end cap around the valve piston. The inner cap includes an inlet port for porting pressure to the valve piston. In addition, a main seal is coupled to the valve piston for sealing the cylinder assembly from supply pressure while pressure is ported to the valve piston by the inner cap for holding the piston assembly in the non-actuated position. The main seal seals pressure ported to the valve piston by the inner cap from supply pressure ported to the piston assembly. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a backflow valve and specifically to a backflow valve that can be used in a home sewer conduit for preventing backflow conditions.
Most homes and businesses include a sewer outlet that leads to a city sewer system. On occasion the sewer outlet will back up, and the sewage will back up into the basement or home of the individual owner. It is desirable to provide a backflow valve that prevents the backflow of sewage into the home.
Therefore a primary object of the present invention is the provision of a backflow valve that will prevent backflow of sewage into a home or office.
A further object of the present invention is the provision of a backflow valve that includes both first, second and third valve members capable of closing off both the entrance and the exit of sewage and bladder seal between entrance and exit flap valves assuring a drop tight seal when a backflow condition occurs.
A further object of the present invention is the provision of a backflow valve that is simple in operation and utilizes a minimum of moving parts.
A further object of the present invention is the provision of a backflow valve that can be easily installed into a conventional sewage system of a home, office or other facility.
A further object of the present invention is the provision of a backflow valve that is economical to use, durable in use, and efficient in operation.
SUMMARY OF THE INVENTION
The foregoing objects may be achieved by a backflow valve for detecting a backflow condition of liquid flowing through a conduit. The backflow valve comprises a valve housing including a valve cavity, an inlet to the valve cavity for receiving the liquid flowing through the conduit and an outlet to the valve cavity for permitting the liquid to exit from the cavity and return to the conduit. A switch is in liquid communication with the valve cavity. The switch is moveable from an off position to an on position in response to liquid filling the valve cavity from a normal liquid level to a backflow liquid level above the normal liquid level. A valve is moveable from an open position permitting liquid flow from the inlet through the valve cavity to the outlet to a close position shutting off liquid flow from the inlet into the valve cavity. A valve actuator is moveable from a first position permitting the valve to be in the open position to a second position moving the valve from the open position to the closed position. The valve actuator is responsive to the switch being in the on position to move the valve from the open to the closed position.
According to another feature of the present invention the valve actuator is a bladder that is inflatable to move from the first to the second position.
According to another feature of the present invention the valve comprises a moveable flap that is moveable in response to inflation of the bladder to move from the open to the closed position.
According to another feature of the present invention the valve comprises both a first flap and a second flap. The first flap is moveable from the open to the closed position to shut off liquid flow from the inlet to the valve cavity. The second flap is moveable from the open to the closed position to shut off liquid flow from the valve cavity to the outlet.
According to another feature of the present invention the first and second flaps are part of a flexible member that is biased towards the open position, but is moveable in response to being engaged by the bladder to the closed position.
According to another feature of the present invention the flexible member is elastic and returns automatically to the open position when the bladder is in the first position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a backflow valve of the present invention.
FIG. 2 is a perspective view of the backflow valve with the internal components removed for illustrative purposes.
FIG. 3 is a sectional view taken along line 3 - 3 of FIG. 2 but showing the internal components in place.
FIG. 4 is a sectional view similar to FIG. 3 , but showing the bladder in the inflated condition.
FIG. 5 is a sectional view taken along line 5 - 5 of FIG. 2 but showing the internal components in place.
FIG. 6 is a sectional view taken along line 6 - 6 of FIG. 3 .
FIG. 7 is a sectional view taken along line 7 - 7 of FIG. 3 .
FIG. 8 is a sectional view taken along line 8 - 8 of FIG. 3 .
FIG. 9 is a schematic view of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Below is a description of the preferred embodiment of the present invention. This description is of the preferred embodiment, and other embodiments may incorporate the same invention while at the same time producing the same result as the preferred embodiment.
Referring to FIG. 1 , a backflow valve 10 is shown in an exploded view. Backflow valve 10 includes a valve box 12 which discloses a valve cavity 14 . Valve cavity 14 is comprised of a bladder cavity 15 and an L-shaped float cavity 18 which includes a first L portion 21 and a second L portion 23 . All the cavities 15 , 18 , 21 and 23 are in fluid communication with one another. A separate air inlet cavity 16 is separate from and is not in communication with the valve cavity 14 , the bladder cavity 15 , the L-shaped float cavity 18 , the first L portion 21 and the second L portion 23 . Extending through the end wall of box 12 is an air tube inlet 17 , and extending between the air inlet cavity 16 and the bladder cavity 15 is an air tube notch 19 . As can be seen in FIG. 5 , an air tube or conduit 58 extends from the exterior of the box 12 through the air tube inlet 17 and the air tube notch 19 . Also, an electrical wire 60 extends through air tube inlet 17 and also through a sealed opening 61 into the second L portion 23 of L-shaped float cavity 18 .
Within the second L portion 23 is a float switch 20 which is comprised of an anchor 74 and a float 76 that pivots about pivot 78 of anchor 74 ( FIG. 5 ). The float switch 20 is electrically connected to the wire 60 . While a float switch may be used, other apparatus for detecting the level of fluid within L portion 23 of L-shaped cavity 18 may be used.
Within bladder cavity 15 is a valve member 22 which includes a first valve flap 24 and a second valve flap 26 . The valve member 22 may be comprised of a flexible material such as rubber or the like. The flaps 24 , 26 are capable of bending downwardly, but have sufficient resiliency to return to their original position shown in FIG. 1 .
Above the valve flap 22 is a bladder collar 28 having an oval shaped opening 30 therein.
Above the bladder collar 28 is a convoluted bladder member 32 which includes a bladder 34 which is oval in shape to conform to opening 30 and which includes accordion folds 36 therein.
The bladder member 32 is comprised of a flexible material such as rubber or the like and includes sufficient resiliency to permit the bladder 34 to move in response to air pressure from the position shown in FIG. 3 to the expanded position shown in FIG. 4 . The bladder member 32 however has sufficient resiliency to return to its original position shown in FIGS. 1 and 3 when air pressure is removed from the upper portion of the bladder 32 .
Above the bladder member 32 is a manifold 38 which is comprised of an upper manifold sheet 40 and a lower manifold sheet 42 . The air tube 58 extends through air tube notch 19 as shown in FIG. 5 and is in communication between the upper and lower manifold sheets 40 , 42 as illustrated schematically by the numeral 58 in FIGS. 3 and 4 . The manifold 38 , the bladder 32 , the bladder collar 28 , and the valve member 22 each include a plurality of screw holes 46 around their perimeters for receiving screws that extend into the valve box 12 .
A transparent lid 48 having a plurality of screw holes 50 therein is fitted and screwed within a recess 52 in the upper edges of the box 12 so as to create a fluid tight seal over box 12 .
A liquid or sewage entrance 56 is in a pipe shape and extends into communication with the valve cavity 14 . Similarly a liquid or sewage exit 54 leads from the valve cavity 14 to return the sewage or liquid to the conduit through which it flows. In operation, the liquid entrance 56 is placed in communication with the upstream end of the sewage conduit and the liquid exit 54 is placed in communication with the downstream portion of the sewage conduit.
Referring to FIG. 5 , the second L portion 23 includes a sloped floor 62 which slopes to a lower end in communication with the L-shaped portion 21 . As can be seen in FIG. 3 , the L-shaped portion 21 is in fluid communication with the liquid entrance 56 . Similarly, the bladder cavity 15 is in communication with the liquid exit 54 .
Referring to FIGS. 6 and 7 , an inlet opening 66 provides communication from the inlet opening 66 , and an outlet opening 64 is in communication with the liquid exit 54 .
FIGS. 3 , 4 and 5 show the operation of the backflow valve 10 . In normal operation, the sewage or liquid enters entrance 56 , then into L-shaped cavity 21 , then passes through inlet opening 66 into bladder cavity 15 , then passes through outlet opening 64 and then into liquid exit 54 . As long as there is no blockage, the valve 10 continues to function in this manner which is shown in FIG. 3 . Arrow 84 shows the direction of fluid flow.
However, if a backflow condition occurs or a blockage occurs, FIG. 5 shows the switch 20 which includes the float 76 that moves to the position shown in shadow lines in FIG. 5 . This movement is caused by the rise of fluid within L-shaped chamber 18 which includes cavities 21 and 23 . This causes the switch 20 to move from its closed position to its open position thereby actuating fluid or air pump 82 shown in FIG. 9 . A power source 80 is also shown in FIG. 9 . The air pump 82 pumps fluid or air through air tube 58 into the manifold 38 . From the manifold 38 the air pressure moves through an air opening 72 against the bladder 32 . The bladder 32 , because of its accordion folds 36 moves from the position shown in FIG. 3 to the position shown in FIG. 4 . In this inflated condition, the bladder 32 engages the first and second valve flaps 24 , 26 and urges them to the position shown in FIG. 4 which is in covering sealing relationship over the inlet opening 66 and the outlet opening 64 respectively. In this position, the valve flaps 24 , 26 prevent fluid from passing from the entrance 56 outwardly through the exit 54 . Thus the backflow valve 10 will remain in a closed condition so long as blockage occurs and a backflow condition is present. However, if for some reason the fluid level lowers in first L portion 21 and second L portion 23 , the switch 20 will again move to its closed position and the air will be permitted to exit from bladder 32 . This causes the bladder 32 to return to its position shown in FIG. 3 . Facilitating of the deflation of bladder 32 may be accomplished by actuating a release valve (not shown) in the air pump 82 or in the conduit 58 to permit the air to escape.
In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstance may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims. | The backflow valve of the present invention includes a valve housing having a cavity therein with an inlet and an outlet to the valve cavity. A switch is in communication with the valve cavity and is moveable from an off position to an on position in response to liquid filling the valve cavity. A valve is moveable in response to the movement of the switch to the on position. The valve moves to a closed position shutting off the fluid flow through the backflow valve. | 5 |
RELATED APPLICATION
This patent arises from a continuation of U.S. patent application Ser. No. 11/959,399, filed on Dec. 18, 2007, which is hereby incorporated by reference in its entirety.
BACKGROUND
Advertisers, media producers, educators and other relevant parties have long desired to understand the responses their targets—customers, clients and pupils—have to their particular stimulus in order to tailor their information or media instances to better suit the needs of these targets and/or to increase the effectiveness of the media instance created. A key to making a high performing media instance is to make sure that every event in the media instance elicits the desired responses from the viewers, not responses very different from what the creator of the media instance expected. The media instance herein can be but is not limited to, a video, an advertisement clip, a movie, a computer application, a printed media (e.g., a magazine), a video game, a website, an online advertisement, a recorded video, a live performance, a debate, and other types of media instance from which a viewer can learn information or be emotionally impacted.
It is well established that physiological response is a valid measurement for viewers' changes in emotions and an effective media instance that connects with its audience/viewers is able to elicit the desired physiological responses from the viewers. Every media instance may have its key events/moments—moments which, if they do not evoke the intended physiological responses from the viewers, the effectiveness of the media instance may suffer significantly. For a non-limiting example, if an ad is intended to engage the viewers by making them laugh, but the viewers do not find a 2-second-long punch-line funny, such negative responses to this small piece of the ad may drive the overall reaction to the ad. Although survey questions such as “do you like this ad or not” have long been used to gather viewers' subjective reactions to a media instance, they are unable to provide more insight into why and what have caused the viewers reacted in the way they did.
SUMMARY
An approach enables an event-based framework for evaluating a media instance based on key events of the media instance. First, physiological responses are derived and aggregated from the physiological data of viewers of the media instance. The key events in the media instance can then be identified, wherein such key events drive and determine the viewers' responses to the media instance. Causal relationship between the viewers' responses to the key events and their surveyed feelings about the media instance can further be established to identify why and what might have caused the viewers to feel the way they do.
Such an approach provides information that can be leveraged by a creator of the media instance to improve the media instance. For a non-limiting example, if a joke in an advertisement is found to drive purchase intent of the product advertised, but the advertisement's target demographic does not respond to the joke, the joke can be changed so that the advertisement achieves its goal: increasing product purchase intent in the target demographic.
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 features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. These and other advantages of the present disclosure will become apparent to those skilled in the art upon a reading of the following descriptions and a study of the several figures of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts an example of a system to support identification of key events in a media instance that drive physiological responses from viewers.
FIG. 2 depicts a flowchart of an exemplary process to support identification of key events in a media instance that drive physiological responses from viewers.
FIGS. 3( a )-( c ) depict exemplary traces of physiological responses measured and exemplary dividing lines of events in a media instance.
FIGS. 4( a )-( c ) depict exemplary event identification results based on different event defining approaches.
FIG. 5 depicts results from exemplary multivariate regression runs on events in an advertisement to determine which events drive the viewers' responses the most.
FIGS. 6( a )-( b ) depict exemplary correlations between physiological responses from viewers to key jokes in an ad and the surveyed intent of the viewers to tell others about the ad.
DETAILED DESCRIPTION
The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” or “some” example(s) in this disclosure are not necessarily to the same example, and such references mean at least one. Although the subject matter is described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.
Although the diagrams depict components as functionally separate, such depiction is merely for illustrative purposes. It will be apparent to those skilled in the art that the components portrayed in this figure can be arbitrarily combined or divided into separate software, firmware and/or hardware components. Furthermore, it will also be apparent to those skilled in the art that such components, regardless of how they are combined or divided, can execute on the same computing device or multiple computing devices, and wherein the multiple computing devices can be connected by one or more networks.
Physiological data, which includes but is not limited to heart rate, brain waves, electroencephalogram (EEG) signals, blink rate, breathing, motion, muscle movement, galvanic skin response and any other response correlated with changes in emotion of a viewer of a media instance, can give a trace (e.g., a line drawn by a recording instrument) of the viewer's responses while he/she is watching the media instance. The physiological data can be measure by one or more physiological sensors, each of which can be but is not limited to, an electroencephalogram, an accelerometer, a blood oxygen sensor, a galvanometer, an electromyograph, skin temperature sensor, breathing sensor, and any other physiological sensor.
The physiological data in the human body of a viewer has been shown to correlate with the viewer's change in emotions. Thus, from the measured “low level” physiological data, “high level” (i.e., easier to understand, intuitive to look at) physiological responses from the viewers of the media instance can be created. An effective media instance that connects with its audience/viewers is able to elicit the desired emotional response. Here, the high level physiological responses include, but are not limited to, liking (valence)—positive/negative responses to events in the media instance, intent to purchase or recall, emotional engagement in the media instance, thinking—amount of thoughts and/or immersion in the experience of the media instance, adrenaline—anger, distraction, frustration, and other emotional experiences to events in the media instance. In addition, the physiological responses may also include responses to other types of sensory stimulations, such as taste and/or smell, if the subject matter is food or a scented product instead of a media instance.
FIG. 1 depicts an example of a system 100 to support identification of key events in a media instance that drives physiological responses from viewers. In the example of FIG. 1 , the system 100 includes a response module 102 , an event defining module 104 , a key event module 106 , and a reaction database 108 .
The response module 102 is a software component which while in operation, first accepts and/or records physiological data from each of a plurality of viewers watching a media instance, then derives and aggregates physiological responses from the collected physiological data. Such derivation can be accomplished via a plurality of statistical measures, which include but are not limited to, average value, deviation from mean, 1st order derivative of the average value, 2nd order derivative of the average value, coherence, positive response, negative response, etc., using the physiological data of the viewers as inputs. Facial expression recognition, “knob” and other measures of emotion can also be used as inputs with comparable validity. Here, the physiological data may be either be retrieved from a storage device or measured via one or more physiological sensors, each of which can be but is not limited to, an electroencephalogram, an accelerometer, a blood oxygen sensor, a galvanometer, an electromyograph, and any other physiological sensor either in separate or integrated form. The derived physiological responses can then be aggregated over the plurality of viewers watching one or more media instances.
The event defining module 104 is a software component which while in operation, defines and marks occurrences and durations of a plurality of events happening in the media instance. The duration of each of event in the media instance can be constant, non-linear, or semi-linear in time. Such event definition may happen either before or after the physiological data of the plurality of viewers has been measured, where in the later case, the media instance can be defined into the plurality of events based on the physiological data measured from the plurality of viewers.
The key event module 106 is a software component which while in operation, identifies one or more key events in the media instance and reports the key events to an interested party of the media instance, wherein the key events drive and determine the viewers' physiological responses to the media instance. Key events in the media instance can be used to pinpoint whether and/or which part of the media instance need to be improved or changed, and which part of the media instance should be kept intact. For non-limiting examples, the key event module may identify which key event(s) in the media instance trigger the most positive or negative responses from the viewers, or alternatively, which key event(s) are polarizing events, e.g., they cause large discrepancies in the physiological responses from different demographic groups of viewers, such as between groups of men and women, when the groups are defined by demographic characteristics. In addition, the key event module is operable to establish a causal relationship between the viewers' responses to the events in the media instance and their surveyed feelings about the media instance so that creator of the media instance may gain insight into the reason why and what key events might have caused the viewers to feel the way they do.
The reaction database 108 stores pertinent data of the media instance the viewers are watching, wherein the pertinent data includes but is not limited to survey questions and results asked for each of the plurality of viewers before, during, and/or after their viewing of the media instance. In addition, the pertinent data may also include but is not limited to the following:
Events/moments break down of the media instance; Key events in the media instance; Metadata of the media instance, which can include but is not limited to, production company, brand, product name, category (for non-limiting examples, alcoholic beverages, automobiles, etc), year produced, target demographic (for non-limiting examples, age, gender, income, etc) of the media instance. If the subject matter is food or a scented product instead of a media instance, the surveyed reactions to the taste or smell of a key ingredient in the food or scented product. Here, the term database is used broadly to include any known or convenient means for storing data, whether centralized or distributed, relational or otherwise.
While the system 100 depicted in FIG. 1 is in operation, the response module 102 derives aggregated physiological responses from the physiological data of a plurality of viewers watching a media instance. The key event module 106 identifies, among the plurality of events in the media instance as defined by the event defining module 104 , one or more key events that drive and determine the viewers' physiological responses to the media instance based on the aggregated physiological responses from the viewers. In addition, the key event module 106 may retrieve outcomes to questions surveyed from the viewers of the media instance from the reaction database 108 , and correlates the viewers' responses to the key events and their surveyed feelings about the media instance to determine what might have caused the viewers to feel the way they do. The entire approach can also be automated as each step of the approach can be processed by a computing device, allowing for objective measure of a media without much human input or intervention.
FIG. 2 depicts a flowchart of an exemplary process to support identification of key events in a media instance that drive physiological responses from viewers. Although this figure depicts functional steps in a particular order for purposes of illustration, the process is not limited to any particular order or arrangement of steps. One skilled in the art will appreciate that the various steps portrayed in this figure could be omitted, rearranged, combined and/or adapted in various ways.
Referring to FIG. 2 , physiological responses can be derived and aggregated from the physiological data of a plurality of viewers watching a media instance at block 202 . At block 204 , the media instance can be defined into a plurality of events, and correlation between the physiological responses from the viewers to the key events in the media instance and a surveyed outcome of their feelings about the media instance can optionally be established at block 206 . At block 208 , key events in the media instance can be identified based on the aggregated physiological responses from the viewers and/or the correlation between the physiological responses and a surveyed outcome. Finally, the key events and/or their correlation with the surveyed outcome are reported to an interested party of the media instance at block 210 , wherein the interested party may then improve the media instance based on the key events and/or the correlations.
Events Definition
In some examples, the event defining module 104 is operable to define occurrence and duration of events in the media instance based on salient positions identified in the media instance. Once salient positions in the media instance are identified, the events corresponding to the salient positions can be extracted. For a non-limiting example, an event in a video game may be defined as a “battle tank” appearing in the player's screen and lasting as long as it remains on the screen. For another non-limiting example, an event in a movie may be defined as occurring every time a joke is made. While defining humor is difficult, punch line events that are unexpected, absurd, and comically exaggerated often qualify as joke events.
FIG. 3( a ) shows an exemplary trace of the physiological response—“Engagement” for a player playing Call of Duty 3 on the Xbox 360. The trace is a time series, with the beginning of the session on the left and the end on the right. Two event instances 301 and 302 are circled, where 301 on the left shows low “Engagement” during a game play that happens during a boring tutorial section. 302 shows a high “Engagement” section that has been recorded when the player experiences the first battle of the game. FIG. 3( b ) shows exemplary vertical lines that divide a piece of media instance into many events defining every important thing that a player of the video game or other media may encounter and/or interact with.
In some examples, the event defining module 104 is operable to define occurrence and duration of events in the media instance via at least the one or more of the following approaches. The events so identified by the event defining module 104 are then provided to the key event module 106 to test for “significance” as key events in the media instance as described below.
The hypothesis approach, which utilizes human hypothesis to identify events in the media instance, wherein such events shall be tested for significance as key events.
The small pieces or time shift approach, which breaks the media instance into small pieces in time, and scans each small piece for significant switch in the viewers' responses, wherein consecutive significant small pieces can be integrated as one key event. For the non-limiting example of FIG. 4( a ), the small pieces are each ⅕ second in length and consecutive small pieces that are found to be significant indicate an event, such as 401 and 402 . For the exemplary car ad shown in FIG. 4( b ), 403 represents the first 10 seconds of the car ad as a cross-component event, and 404 represents a cross-ad music event.
The turning point approach, which finds where the aggregated physiological responses (traces), first derivative, and second derivative of aggregated trace(s) have roots and uses them as possible event cut points (delimiters). Here, roots of the aggregate traces can be interpreted as points when the viewers' aggregated physiological responses transition from above average to below average, or from positive to negative. Roots in the first derivative of the aggregate traces can be interpreted as ‘turning points’, at which the physiological responses transition from a state of increasing positivity to increasing negativity, or vice versa. Roots in the second derivative of the aggregate traces can also be interpreted as ‘turning points’, points, at which the physiological responses begin to slow down the rate of increase in positivity. All such roots are then collected in a set s. For every pair i,j of roots in the set s for which j occurs after i in the media instance, the event which starts at i and ends at j is tested for significance as a key event. Note here that i and j do not have to be consecutive in time.
The multi-component event approach, which breaks the media instance down into components and then divides each component into events. A media instance typically has many components. For a non-limiting example, an advertisement can have one or more of: voiceover, music, branding, and visual components. All points in the media instance for which there is a significant change in one of the components, such as when the voiceover starts and ends, can be human marked. As with the turning point approach, all the marked points can be collected in the set s. For every pair i,j of roots in the set s for which j occurs after i in the media instance, the event which starts at i and ends at j is tested for significance as a key event. While this approach requires greater initial human input, it may provide more precise, more robust results based on automated higher-level analysis and the benefits would outweigh the costs. For a non-limiting example, a car ad can be broken down into visual, dialogue, music, text, and branding components, each with one or more events. For the exemplary car ad shown in FIG. 4( c ), 405 represents a visual event, 406 represents a dialogue event, and 407 represents a music event.
Key Events Identification
In some examples, the key event module 106 is operable to accept the events defined by the event defining module 104 and automatically spot statistically significant/important points in the aggregated physiological responses from the viewers relevant to identify the key moments/events in the media instance. More specifically, the key event module is operable to determine one or more of:
if an event polarizes the viewers, i.e., the physiological responses from the viewers are either strongly positive or strongly negative. if the physiological responses vary significantly by a demographic factor. if the physiological responses are significantly correlated with the survey results. if an event ranks outstandingly high or low compared to similar events in other media instances For a non-limiting example, FIG. 3( c ) shows two exemplary traces of the “Engagement” response of a video game player where the boxes 303 , 304 , and 305 in the pictures correspond to “weapon use” events. At each point where the events appear, “Engagement” rises sharply, indicating that the events are key events for the video game.
In some examples, the key events found can be used to improve the media instance. Here “improving the media instance” can be defined as, but is not limited to, changing the media instance so that it is more likely to achieve the goals of the interested party or creator of the media instance.
In some examples, the key event module 106 is further operable to establish a casual relationship between surveyed feelings about the media instance and the key events identified based on the physiological responses from the viewers. In other words, it establishes a correlation between the physiological responses from the viewers to key events in the media instance and a surveyed outcome, i.e., the viewers' reported feelings on a survey, and reports to the interested parties (e.g. creator of the event) which key events in the media instance actually caused the outcome. Here, the outcome can include but is not limited to, liking, effectiveness, purchase intent, post viewing product selection, etc. For a non-limiting example, if the viewers indicate on a survey that they did not like the media instance, something about the media instance might have caused them to feel this way. While the cause may be a reaction to the media instance in general, it can often be pinned down to a reaction to one or more key events in the media instance as discussed above. The established casual relationship explains why the viewers report on the survey their general feelings about the media instance the way they do without human input.
In some examples, the key event module 106 is operable to adopt multivariate regression analysis via a multivariate model that incorporates the physiological responses from the viewers as well as the surveyed feelings from the viewers to determine which events, on average, are key events in driving reported feelings (surveyed outcome) about the media instance. Here, the multivariate regression analysis examines the relationship among many factors (the independent variables) and a single, dependent variable, which variation is thought to be at least partially explained by the independent variables. For a non-limiting example, the amount of rain that falls on a given day varies, so there is variation in daily rainfall. Both the humidity in the air and the number of clouds in the sky on a given day can be hypothesized to explain this variation in daily rainfall. This hypothesis can be tested via multivariate regression, with daily rainfall as the dependent variable, and humidity and number of clouds as independent variables.
In some examples, the multivariate model may have each individual viewer's reactions to certain key events in the media instance as independent variables and their reported feeling about the media instance as the dependent variable. The coefficients from regressing the independent variables on the dependent variable would determine which key events are causing the reported feelings. Such a multivariate model could be adopted here to determine what set of key events most strongly affect reported feelings from the viewers about the media instance, such as a joke in an advertisement. One characterization of such event(s) is that the more positive (negative) the viewers respond to the event(s), the more likely the viewers were to express positive feelings about the media instance. For a non-limiting example, a multivariate regression can be run on multiples events (1, 2 . . . n) within an entire montage sequence of an advertisement to determine which events drive liking the most, using relationship between reported feelings about the ad and the emotional responses from the viewers to the events in the ad as input. The results of the multivariate regression runs shown in FIG. 5 indicate that 2 out of the 6 events tested in the ad drive the viewers' responses the most, while the other 4 events do not meet the threshold for explanatory power.
In an automated process, this multivariate regression may be run stepwise, which essentially tries various combinations of independent variables, determining which combination has the strongest explanatory power. This is a step toward creating the causal relationship between the viewers' responses to the events and their surveyed feelings about the media instance. For a non-limiting example, if response to joke #2 is correlated with indicated intent to purchase when holding genders and responses to jokes #1 and #3 constant, a causal conclusion can be made that joke #2 triggers the viewers' intent to purchase.
In some examples, the key event module 106 identifies the key polarizing event(s) that cause statistically significant difference in the surveyed outcome from different demographic groups of viewers and provides insight into, for non-limiting examples, why women do not like the show or which issue actually divides people in a political debate. The key event module 106 may collect demographic data from overall population of the viewers and categorize them into groups to differentiate the responses for the subset, wherein the viewers can be grouped one or more of: race, gender, age, education, demographics, income, buying habits, intent to purchase, and intent to tell. Such grouping information can be included in the regressions to determine how different groups report different reactions to the media instance in the survey. Furthermore, grouping/event response interaction variables can be included to determine how different groups respond differently to the key events in the media instance. For key events that are polarizing, demographic information and/or interaction variables of the viewers can also be included to the multivariate model capture the combined effect of the demographic factor and the reaction to the polarizing key events.
For a non-limiting example, the viewers of an ad can be first asked a survey question, “How likely are you to tell someone about this particular commercial—meaning tell a friend about this ad you've just seen” as shown in FIG. 6( a ). The viewers of the ad are broken into two groups based on indicated likelihood to tell someone about the commercial—the affirmative group and the negative group, and it is assumed that the viewers in both groups are normally distributed with the same variance. The emotional responses from the viewers in the groups to two key jokes 601 and 602 in the ad are then compared to their surveyed reactions to test the following hypothesis—“the group that indicated they were likely to tell someone will have a stronger positive physiological response to the two key jokes than the group that indicated they were unlikely to tell someone.” The affirmative group that indicated they were likely to tell a friend had, on average, a more positive reaction to both jokes than the negative group that indicated they were unlikely to tell a friend. In both cases, experiments using the change in individual liking as the metric to measure the physiological response rejects the null hypothesis—that there was no difference in emotional response to the jokes between the two groups—at above the 95% confidence level. Referring to graphs in FIG. 6( a ), the X axis displays the testers' likelihood to tell a friend as indicated on the post-exposure survey and the Y axis displays the testers' emotional response to the joke. The triangles represent the “Go” people—those who indicated they were likely (to varying degrees) to tell their friend about the spot. The circles represent those who indicated that they were unlikely to do so. Note the upward trends—the more positive the emotional reaction to the joke, the greater indicated likelihood to tell a friend about the spot. FIG. 6( b ) further summarizes the physiological responses to both jokes, where the reaction to the Crying Wife is on the X axis and the reaction to the Dead Husband is on the Y axis. An imaginary line around is drawn around the viewers who reacted relatively positively to both jokes. Note that this line corrals most of the black diamonds, which represent viewers who indicated they would tell a friend about the ad.
One example may be implemented using a conventional general purpose or a specialized digital computer or microprocessor(s) programmed according to the teachings of the present disclosure, as will be apparent to those skilled in the computer art. Appropriate software coding can readily be prepared by skilled programmers based on the teachings of the present disclosure, as will be apparent to those skilled in the software art. The disclosure may also be implemented by the preparation of integrated circuits or by interconnecting an appropriate network of conventional component circuits, as will be readily apparent to those skilled in the art.
One example includes a computer program product which is a machine readable medium (media) having instructions stored thereon/in which can be used to program one or more computing devices to perform any of the features presented herein. The machine readable medium can include, but is not limited to, one or more types of disks including floppy disks, optical discs, DVD, CD-ROMs, micro drive, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of media or device suitable for storing instructions and/or data. Stored on any one of the computer readable medium (media), the present disclosure includes software for controlling both the hardware of the general purpose/specialized computer or microprocessor, and for enabling the computer or microprocessor to interact with a human viewer or other mechanism utilizing the results of the present disclosure. Such software may include, but is not limited to, device drivers, operating systems, execution environments/containers, and applications.
The foregoing disclosed examples has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations will be apparent to the practitioner skilled in the art. Particularly, while the concept “module” is used in the examples of the systems and methods described above, it will be evident that such concept can be interchangeably used with equivalent concepts such as, class, method, type, interface, bean, component, object model, and other suitable concepts. Examples were chosen and described in order to best describe the principles of the disclosure and its practical application, thereby enabling others skilled in the art to understand the disclosure, the various examples and with various modifications that are suited to the particular use contemplated. It is intended that the scope of the disclosure be defined by the following claims and their equivalents. | Example methods, systems, apparatus and machine readable media are disclosed to identify candidate media events for modification. An example method includes dividing a media instance into components and correlating physiological response data from a subject exposed to the media with the components to form correlated data. The example method also includes processing the correlated data to identify transitions representative of changes in a subject response. The example method also includes parsing the components a plurality of events based on the transitions. In addition, the example method includes identifying events of the plurality of events as candidates for modification based on the changes in the subject response. | 7 |
BACKGROUND OF THE INVENTION
It is known that, to produce glass fiber insulating materials, glass or mineral wool felts may be sprayed with aqueous adhesives based on phenol-formaldehyde resins or urea-formaldehyde resins for the purposes of consolidation. Adhesives having very high water contents have to be used because the adhesive is applied to the still highly heated glass or mineral mass and thermal decomposition phenomena and observed with low water contents. The water applied is evaporated during subsequent hardening of the adhesives and is let off as waste air.
It is not possible to prevent parts of the adhesive components from being lost together with the waste air. This is an economic disadvantage because this part of the adhesive is lost during formation of the bond. Above all, however, this process is attended by significant disadvantages when physiologically harmful, readily volatile components are given off with the waste air, as in the case of formaldehyde-containing adhesives, for example.
Accordingly, it is extremely desirable both for economic and for ecological reasons to reduce the proportion of readily volatile adhesive components in the waste air without at the same time losing the desirable properties of the adhesives.
This problem is solved by the present invention.
SUMMARY OF THE INVENTION
Surprisingly, it has been found that emulsions of isocyanates and water glass represent extremely effective binders for the consolidation of mineral fibers for the production of mineral fiber mats which contain no volatile constituents apart from water.
Accordingly, the present invention relates to a process for the production of mineral fiber mats by bonding mineral fibers with binders, wherein an emulsion of water glass and isocyanate which has been prepared in a preceding mixing unit is used as binder.
DETAILED DESCRIPTION OF THE INVENTION
The combination of water glass and isocyanate as an adhesive is known, for example from French Patent Nos. 1,429,552 and 1,362,003 and from German Published Patent Specification No. 1,770,384. However, this simultaneous use of isocyanates with water glass is of no commercial value because although the products may be used alongside one another for bonding purposes, the quality of the bonds obtained is no better than in cases where the two components are used on their own.
By contrast, it has surprisingly been found that, by mechanically mixing the two components in standard mixing units, it is possible to obtain stable emulsions of isocyanate/water glass which are eminently suitable for bonding mineral fibers for the production of mineral fiber mats. Although these emulsions are highly viscous, they may still be satisfactorily pumped. Despite the relatively high viscosity thereof, these emulsions may still be dispersed extremely well with air. The degree of dispersion obtained may be considerably better than that obtained in cases where extremely low viscosity adhesive compositions are used.
It has been found that the emulsions used in accordance with the present invention show particularly good adhesion precisely to the surfaces of the mineral fibers.
The water glass used in accordance with the present invention may be any standard commercial-grade water glass, soda water glass and potash water glass being preferred, although it is also possible to use other alkali metal and/or ammonium silicate solutions or mixtures of these substances. It does not matter whether the silicate solutions are present in the form of true aqueous solutions or completely or partly in the form of colloidal solutions.
It is also possible without any disadvantages to use crude technical silicate solutions which contain additional impurities, such as calcium silicates, magnesium silicates, borates or aluminates.
It is preferred to use standard commercial-grade water glasses which have an alkali oxide to silicon dioxide ratio of between about 1:1.8 and 1:4.1 and total solids contents of, in general, from about 28 to 55%.
The concentration of the water glasses used may readily be varied in accordance with the viscosity requirements or in accordance with the necessary water content, although it is preferred to use water glasses having a solids content of from about 40 to 55%, by weight, or water glasses having a viscosity of at least about 100 cP at 25° C.
It is particularly preferred to use water glasses having a solids content of from about 44 to 45%, by weight, or water glasses having a viscosity of at least about 400 cP/25` C.
The nature of the isocyanates used for preparing the dispersions is not critical, although they should best have such a high boiling point that they do not evaporate to any significant extent at 100° C. This prevents significant quantities of the adhesive from volatilizing with the waste air during application or hardening of the adhesive, as may be the case with conventional adhesives.
Suitable isocyanates are monisocyanates, such as n-octyl isocyanate, cyclohexyl isocyanate and phenyl isocyanate, polyisocyanates, such as aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic polyisocyanates of the type described, for example, by W. Siefken in Justus Liebigs Annalen der Chemie, 562, pages 75 to 136, and in Polyurethanes: Chemistry and Technology, Volume I Chemistry by Saunders and Frisch l963 especially pages 17 to 48, for example 1,6-hexamethylene diisocyanate, 1,l2-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3- and 1,4-diisocyanate, also mixtures of these isomers, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl cyclohexane (DAS No. 1,202,785, U.S. Pat. No. 3,401,190 incorporated herein by reference), 2,4- and 2,6-hexahydro-tolylene diisocyanate, also mixtures of these isomers, hexahydro-1,3- and/or 1,4-phenylene diisocyanate, perhydro-2,4'- and/or -4,4'-diphenyl methane diisocyanate, 2,4- and 2,6-tolylene diisocyanate, also mixtures of these isomers, diphenyl methane-2,4' and/or -4,4'-diisocyanate, naphthylene-1,5-diisocyanate, triphenyl methane- 4,4', 4"-triisocyanate, polyphenyl polymethylene polyisocyanates, of the type which may be obtained by condensing aniline with formaldehyde, followed by phosgenation, and which are described, for example, in British Patent Nos. 874,430 and 848,671, m- and p-isocyanatophenyl sulphonyl isocyanates according to U.S. Pat. No. 3,454,606 incorporated herein by reference, perchlorinated aryl polyisocyanates of the type described, for example, in German Auslegeschrift No. 1,157,601 (U.S. Pat. No. 3,277,138 incorporated herein by reference), polyisocyanates containing carbodiimide groups of the type described in German Patent No. 1,092,007 (U.S. Pat. No. 3,152,162 incorporated herein by reference, diisocyanates of the type described in U.S. Pat. No. 3,492,162 incorporated herein by reference polyisocyanates containing allophanate groups of the type described, for example in British Patent No. 994,890, Belgian Patent No. 761,626 and published Dutch Patent Applicaton No. 7,102,524, polyisocyanates containing isocyanurate groups of the type described, for example, in U.S. Pat. No. 3,001,973 incorporated herein by reference, German Patent Nos. 1,022,789; 1,222,067 and 1,027,394 and in German Offenlegungsschrift Nos. 1,929,034 and 2,004,048, polyisocyanates containing urethane groups of the type described, for example, in Belgian Patent No. 752,261 or in U.S. Pat. No. 3,394,164 incorporated herein by reference, polyisocyanates containing acylated urea groups according to German Patent No. 1,230,778, polyisocyanates containing biuret groups of the type described, for example, in German Patent No. 1,101,394 (U.S. Pat. Nos. 3,124,605 and 3,201,372 incorporated herein by reference) and in British Patent No. 889,050, polyisocyanates obtained by telomerization reactions of the type described, for example, in U.S. Pat. No. 3,654,106 incorporated herein by reference, polyisocyanates containing ester groups of the type described, for example, in British Patent Nos. 965,474 and 1,072,956, in U.S. Pat. No. 3,567,763 incorporated herein by reference, and in German Patent No. 1,231,688, reaction products of the above-mentioned isocyanates with acetals according to German Patent No. 1,072,385 and polyisocyanates containing polymeric fatty acid radicals according to U.S. Pat. No. 3,455,883 incorporated herein by reference.
It is also possible to use the isocyanate group-containing distillation residues obtained in the production of isocyanates on a commercial scale, optionally in solution in one or more of the aforementioned polyisocyanates. It is also possible to use mixtures of the aforementioned polyisocyanates.
In general, it is particularly preferred to use the commercially readily available polyisocyanates, for example 2,4- and 2,6- tolylene diisocyanate, also mixtures of these isomers ("TDI"), polyphenyl polymethylene polyisocyanates of the type obtained by condensing aniline with formaldehyde, followed by phosgenation ("crude MDI") and polyisocyanates containing carbodiimide groups, urethane groups, allophanate groups, isocyanurate groups, urea groups or biuret groups ("modified polyisocyanates"). Crude MDI is most preferred.
Suitable mineral fibers are any known mineral fibers, such as glass, asbestos and mineral fibers, preferably glass fibers.
According to the present invention, it is also possible to add additives to one of the two components of the emulsion. These additives may be present in the form of a solution in one of the two components or even in the form of an emulsion or dispersion in one of the two components.
The nature and purpose of the additives are determined by the particular embodiment of the process according to the present invention. Thus, it is possible to use any conventional emulsification aids in order further to stabilize the emulsion formed. Very small quantities of from about 0.01 to 1.00%, by weight, based on the emulsion, will be sufficient because the emulsions produced are extremely stable even without an auxiliary emulsifier.
According to the present invention, catalysts are also frequently used. Examples of suitable known catalysts are, for example, tertiary amines, such as triethyl amine, tributyl amine, N-methyl morpholine, N-ethyl morpholine, N-cocomorpholine, N,N,N'N'-tetramethyl ethylene diamine, 1,4-diazabicyclo-(2,2,2)-octane, N-methyl-N'-dimethyl aminoethyl piperazine, N,N-dimethyl benzyl amine bis-(N,N-diethyl amino ethyl)-adipate, N,N-diethyl benzyl amine, pentamethyl diethylene triamine, N,N-dimethyl cyclohexyl amine, N,N,N',N'-tetramethyl-1,3-butane diamine, N,N-dimethyl-B-phenyl ethyl amine, 1,2-dimethyl imidazole and 2-methyl imidazole. Other suitable catalysts are known Mannich bases of secondary amines, such as dimethyl amine, and aldehydes, preferably formaldehyde, or ketones, such as acetone, methyl ethyl ketone or cyclohexanone, and phenols, such as phenol, nonyl phenol or bis-phenol.
Examples of tertiary amines containing isocyanate-reactive hydrogen atoms which may be used as catalysts are triethanolamine, triisopropanolamine, N-methyl diethanolamine, N-ethyl diethanolamine and N,N-dimethyl ethanolamine, also the reaction products thereof with alkylene oxides, such as propylene oxide and/or ethylene oxide.
Other suitable catalysts are silaamines having carbon-silicon bonds of the type described, for example, in German Patent No. 1,229,290 (corresponding to U.S. Pat. No. 3,620,984 incorporated herein by reference) for example 2,2,4-trimethyl-2-silamorpholine and 1,3-diethyl aminomethyl tetramethyl disiloxane.
Other suitable catalysts are nitrogen-containing bases, such as tetraalkyl ammonium hydroxides, also alkali metal hydroxides, such as sodium hydroxide, alkali metal phenolates, such as sodium phenolate, or alkali metal alcoholates, such as sodium methylate. Hexahydrotriazines may also be used as catalysts.
According to the present invention, organometallic compounds, especially organotin compounds, may also be used as catalysts.
Preferred organotin compounds are tin (II) salts of carboxylic acids, such as tin (II) acetate, tin (II) octoate, tin (II) ethyl hexoate and tin (II) laurate, and the tin (IV) compounds, for example dibutyl tin oxide, dibutyl tin dichloride, dibutyl tin diacetate, dibutyl tin dilaurate, dibutyl tin maleate or dioctyl tin diacetate. It is, of course, possible to use the above-mentioned catalysts in the form of mixtures.
Further representatives of catalysts suitable for use in accordance with the present invention and details on the way in which the catalysts work may be found in Kunststoff-Handbuch, Vol. VII, by Vieweg and Hochtlen, Carl-Hanser-Verlag, Munich, 1966, for example on pages 96 to 102 and Polyurethanes: Chemistry and Technology, Vol. I Chemistry by Saunders and Frisch, l963, especially pages 208 to 214.
The catalysts are generally used in quantities of from about 0.001 to 10%, by weight, based on the emulsion.
According to the present invention, surface-active additives, such as emulsifiers, may also be used. Examples of emulsifiers are the sodium salts of castor oil sulphonates or salts of fatty acids with amines, such as diethyl amine/oleic acid or diethanolamine/stearic acid. Alkali metal or ammonium salts of sulphonic acid, such as those of dodecyl benzene sulphonic acid dinaphthyl methane disulphonic acid, or of fatty acids, such as ricinoleic acid, or of polymeric fatty acids, may also be used as surface-active additives.
According to the present invention, it is also possible to use reaction retarders, for example substances which are acid in reaction, such as hydrochloric acid or organic acid halides.
Other examples of the additives optionally used in accordance with the present invention and also details on the way in which these additives are to be used and how they work, may be found in Kunststoff-Handbuch, Vol. VII, published by Vieweg and Hochtlen, Carl-Hanser-Verlag, Munich, 1966, for example on pages 103 to 113.
Additives which harden the water glass and additives which increase the tackiness of the emulsions formed, such as latices, fillers for extending or for binding the shrinkage level and, optionally, blowing or expanding agents, may also be incorporated into the emulsion.
EXAMPLE 1
100 parts, by weight, of water glass having a solids content of 45% (molar ratio of Na 2 O:SiO 2 =1:2) were intensively mixed for fifteen seconds with 100 parts, by weight, of polyphenyl polymethylene polyisocyanate (NCO content 31 % by weight) by means of a stirrer rotating at 2000 rpm. A light brown emulsion having a viscosity of approximately 40,000 cP is obtained, remaining processible for more than thirty minutes. Thereafter, its viscosity rises slowly to beyond 100 P/25° C.
EXAMPLE 2
100 parts, by weight, of water glass according to Example 1, pumped by means of a high pressure piston pump at 90 bars, are mixed with 25 parts, by weight, of polyisocyanate according to Example 1, which is also pumped by means of a high-pressure piston pump at 120 bars, by means of a toothed stirrer rotating at 2000 rpm. The following viscosities are measured as a function of time (at 25° C.):
Immediately--10 poises
1'--15 poises
2'--17 poises
4'--20 poises
8'--25 poises
60' approximately--100 poises
EXAMPLE 3
100 parts, by weight, of water glass having a solids content of 41% (molar ration of Na 2 O:SiO 2 1:3.1) are mixed with 50 parts, by weight, of polyisocyanate according to Example 1 by means of a toothed stirrer rotating at 1500 rpm, the two components being delivered by means of two low pressure gear pumps. A light brown emulsion is obtained.
EXAMPLE 4
A dispersion according to Example 2 is delivered to a standard spraying nozzle where it is atomized into fine particles by means of compressed air. The spraying nozzle is arranged at a distance of approximately 10 cm in front of the spinning wheels of a standard mineral-fiber spinning machine. The delivery pipe to the nozzle is cooled by an external air jacket through which the air required for spraying is delivered.
The mineral fiber is dried within 2-4 minutes in a stream of hot air (temperature about 200° C.) and pressed to form a mat. Thus, flat, odorless mats having good cohesion are obtained. In all the tests to which they are subjected in accordance with DIN 18 165, sheet 1 or sheet 2, the thus-obtained mats correspond to or exceed the values which are reached with the same quantity of phenol-formaldehyde resin as binder (based on the same quantities of organic material).
Although the invention has been described in detail for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims. | This disclosure teaches a method of forming mineral mates by using an emulsion of water glass and isocyanates as the binder. This binder composition may be readily dispersed with air and has superior adhesion to mineral fibers. | 3 |
This is a division of application Ser. No. 390,897, filed Aug. 23, 1973, now U.S. Pat. No. 3,930,063.
BACKGROUND OF THE INVENTION
This invention relates generally to coating of substrates with an antiskid material and more particularly concerns the coating of substrates with an antiskid material in the form of a silica aquasol, provision being made for observing the uniformity of the coating applied to the substrate.
It is quite common in coating applications to coat a substrate several times, often with a coating which is hard to see with human eye. While this is a common problem with a clear coating, it is also a problem when coatings of similar color to the substrate are made. Often in these coating operations the applicator becomes blocked causing a non-uniform coating to be applied and it is necessary to quickly discover that the application is not uniform so as to correct the applicator.
Some attempts to discover this have used an indicator spray which is sprayed on the coating and gives a characteristic color if the silica is present. However, these indicators have been confined to use on special test panels of the coated substrate which are run infrequently, usually at the start up of the coating application and at spaced intervals to recheck. These indicator sprays cannot be applied to a wet coating due to the solvent incompatability, so the coated substrate must be at least partially dried before the indicator spray is usable. These indicator sprays also form a permanent color change which renders any sprayed coated substrate unusable, so the test panels are usually discarded.
Accordingly it is an object of this invention to provide a composition and method for easily observing the uniformity of application of a silica sol coating. Another object is to provide a means for observing the uniformity of an aqueous silica sol coating application while the coating is still wet. An allied object is to provide a composition and method for observing the uniformity of a silica coating on a substrate without rendering the substrate unusable. A related object is to develop a composition which meets the above objects and one which does not have any adverse effects on the antiskid coating.
SUMMARY OF THE INVENTION
In accordance with the invention, a method for determining the uniformity of application of a silica aquasol coating on a substrate has been found which includes, preparing a liquid coating for application to the substrate and incorporating an indicator which becomes visible when irradiated with radiant energy of a predetermined wave length in the liquid coating. The coating and the indicator are then applied to the substrate and the applied coating is irradiated with the radiant energy of the predetermined wave length to render the indicator visible whereby any blotching or imperfections in application are readily apparent to a worker at an observation station. The applicator can be easily adjusted since the worker knows exactly where the problem occurs, and the imperfect coating on the substrate may be corrected by secondary applicators down the line from the observation station.
Other objects and advantages of the invention will become apparent upon reading and following detailed description. While the invention will be described in connection with a preferred embodiment, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
The preferred form of antiskid agent is that of an aqueous silica sol. Aqueous silica sols with particle diameters from 4 to 150 mu can be used; however, large particle size sols are preferred due to their excellent antiskid performance. The preferred range of particle diameters is from 50 to 150 mu. Of course, other antiskid compositions such as those based on aluminum oxide, other metal oxides or coated silica sols can also be used.
A preferred fluorescent dye is that of Calcofluor White ST, manufactured by American Cyanamid, but other fluorescent dyes can be used. The amount of dye added to the product should be low enough that the properties of the product and of the substrate are not adversely affected but large enough that the dye can be seen on a substrate with the irridiating radiation. This level depends upon the particular dye chosen, the amount of dilution of the antiskid product and the long term stability of the product.
An ultraviolet light is a convenient source of irradiation.
The fluorescent dye is usually applied as a solution rather than a dry powder. It was found that very low fluorescence was observable on the substrate at equivalent levels of fluorescent dye in the powder form being added to the antiskid mixture. A fluorescent brightener is optionally added to the fluorescent dye solution. A preferred mixture is a fluorescent dye dissolved in water containing small amounts of cellosolve and triethanolamine and a fluorescent brightener to give a solution which contains approximately 30% by weight fluorescent material. The cellosolve and triethanolamine are present to facilitate the initial dissolution of the fluorescent dye in water. A preferred brightener is a sulfonated triazinylstilbene known as fluorescent brightener 28, Color Index No. 40622. Some of these brighteners are available from E. I. Dupont and are known as Paper White BN, Paper White BP, Pontamine White BT and Pontamine White BTS.
A preferred antiskid and fluorescent dye coating was prepared consisting of approximately 40% silica concentration and a fluorescent dye concentration of 0.7%.
EXAMPLE 1
A silica sol solution containing 50% SiO 2 having a pH of 8.5, a viscosity of 10 cps and an average particle size of 70 to 120 mu was diluted with water to a 42% silica level, and a dye solution containing 30% Calcofluor White ST dissolved in water containing small amounts of cellosolve and triethanolamine was added with an appropriate amount of water to give a final 40% silica level to the application mixture, and mixed. The final concentration of Calcofluor White ST was 0.7% with approximately 0.2% by weight active fluorescent material. It is usually necessary to mix the fluorescent dye with the water prior to addition to the silica sol in order to prevent formation of gel particles, but accelerated aging tests showed a stability of the mixture of greater than one year.
The mixture of Example 1 was applied to a cellulosic substrate by application means such as a sponge, felt, roller, knife edge or sprayer. An operator can irradiate the coated substrate with ultraviolet light to determine if the applicator is working properly and applying a uniform coating to the entire substrate. Adjustments can be made on the applicator while the machine is running in order to correct any non-uniformity of application.
Antiskid tests were carried out on kraft wrapping paper coated with the above mixture containing a fluorescent dye and also the above mixture without a fluorescent dye. The slide angle was not adversely affected by the dye. Not only were completely uncoated areas easily observable, but also differences in thickness of the application were apparent from the intensity of the fluorescence.
When the prior art indicator sprays were used to check the coating levels, no difference was observed in the color and intensity of the separate indicator whether or not the coating contained a fluorescent dye. However, ultraviolet illumination of the substrate was capable of detecting the coating of antiskid agent at higher dilutions where the reaction of the indicator spray failed but the fluorescence was still present.
Thus, it is apparent that there has been provided, in accordance with the invention, a coating that fully satisfies the objects, aims, and advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the appended claims. | A large particle sized silica sol and a fluorescent dye are mixed together and applied as a coating to a substrate with the application monitored during coating by a light which renders the fluorescent dye visible; if the coating is blotched or uneven, corrections can be made during the run to provide a uniform coating. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to marine engineering structure including revetment, breakwater and quay walls having a wide base and constructed with trusses.
2. Description of the Prior Art
Conventionally, there have been proposed a number of methods for constructing marine engineering structures, which can be selected according to the purposes for which they are intended, soil conditions of the construction site, and other factors. In recent years, however, there has been increasing demand for shortening the period of construction work. For example, rapid construction methods, such as submerging and settling prefabricated concrete caissons at predetermined locations, are employed.
However, such conventional rapid construction methods as just mentioned have such common shortcomings that the sea bed on which caissons rest subsides under their load, etc., making the structures unstable. In many cases, therefore, preliminary works, such as foundation improvement, must be carried out before constructing revetments, breakwaters or other marine engineering structures. However, foundation improvement works can often give rise to secondary pollution problems as a result of diffusion of sea bed sludge and leakage of solidifying agent injected into the sea bed. Such a method is not recommendable for these and other reasons, such as higher costs and problems resulting from conventional rapid construction processes.
SUMMARY OF THE INVENTION
The present invention is to eliminate such shortcomings, providing a marine engineering structure especially suitable for rapid works for constructing a large-scale marine engineering structure (for example 15 meters in height). Thus the present invention provides a marine engineering structure comprising a truss structure which comprises a plurality of trusses spacedly erected vertically, a connecting member for interconnecting the trusses, and floor slab fixed to the lower end of the trusses, said truss structure providing a space into which the prefabricated main body of said marine engineering structure is inserted.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is to provide a marine engineering structure constructed in such manner that a plurality of trusses are spacedly erected vertically and are inter-connected by steel members, or other materials and floor slabs are laid over the entire bottom to form a truss structure having wide base, and that after sinking and settling said truss structure onto sea bed, the prefabricated main body of the marine engineering structure (for example, hollow square concrete column) is inserted into, and fixed in place among, said trusses in a row. Also, according to purposes, riprap, wave-breaking blocks, or other materials may be placed for protection of the sea bed in the front of or in the rear of the structure. The main body of the marine engineering structure does not necessarily have to be a single structure.
In such structure as mentioned above, by inserting and fixing in place the main body of a marine engineering structure into truss structures submerged and settled onto a predetermined position in the sea bed, said main bodies can be very rapidly constructed and at the same time, satisfactory stability of the main bodies can be achieved, facilitating various incidental works to be done subsequently. Furthermore, since the weight of the structure (chiefly the weight of the main bodies) is distributed to the side floor slab of the truss structure to reduce the pressure per unit area bearing on the base, and since said main bodies are supported by the truss structures, they can be appreciably simple in construction and yet provide sufficient structural stability, as compared with conventional types. This permits the total weight of the structure to be comparatively small. Therefore, its applicability to soft foundation will be greatly increased, without employing conventional foundation improvement processes.
DESCRIPTION OF PREFERRED EMBODIMENTS
Now the present invention will be explained referring to an example shown in the drawings.
Brief Explanation of the Drawings:
FIG. 1 and FIG. 2 show a marine engineering structure intended for use as a bulkhead or breakwater.
In the drawings, 1 is a vertically extending truss structure with a horizontally arranged base. As already mentioned, the truss structure 1 is constructed by spacedly erecting vertically a plurality of open-sided trusses 2, interconnecting them by steel members 3 or other materials, and by fixing floor slab 4 to the entire base.
Truss structure 1 thus built will be submerged and settled onto a predetermined sea bed position. The main bodies 5 prefabricated on shore (for example, hollow square concrete columns) will then be inserted through upper openings of the truss structure 1 and fixed in place to provide fills. By executing said work between trusses 2 in turns or simultaneously, the main bodies of the marine engineering structure will be formed in a row.
The truss structure 1 may not fit right into the uneven surface of the sea bed as it has a very wide floor slab 4. In such case, openings (not shown in the drawings) can be provided beforehand at the floor slab 4 to pump in sand or other material through such openings after said structure 1 has been submerged and settled onto the sea bed, with a view to adjusting the sea bed surface, so as to secure structural stability.
The main bodies of the marine engineering structure of the present invention can be completed in this manner. Depending on the purposes for which the marine engineering structure is intended, for example, in the case of a breakwater, riprap 6 will be provided on front offshore side of said structure and additionally wave-breaking blocks 7 laid, thus completing the entire construction works.
As explained above, the marine engineering structure to which the present invention relates can be almost completed by a rapid construction method whereby the prefabricated main bodies of concrete or other material are inserted and fixed in place into truss structure having a base. Since the main bodies of said marine engineering structure can be of simple and light construction as compared with those of similar dimensions built by conventional methods, they are easier to form and transport and as such are less costly. Further, the total weight of the marine engineering structure will be distributed all over the wide floor slab, reducing the pressure per unit area and possibility of a decrease in structural stability resulting from subsidence of the sea bed or other causes. All this adds greatly to the applicability of said marine engineering structure to soft foundation as well as its practical utility. | A marine engineering structure with a wide base comprising a truss structure constructed by interconnecting a plurality of long trusses spacedly erected vertically and by fixing a floor slab to thin lower end thereof, and prefabricated main body of said marine engineering structure inserted into a space provided by said truss structure. | 4 |
BACKGROUND OF THE INVENTION
[0001] The device as disclosed herein is a modular device for holding and cutting sheet goods, and more particularly is an inexpensive support rack that can be taken down for transport between job sites or storage and reassembled at a job site to support a standard sized sheet of sheet goods for accurate cutting to a desired size for use.
[0002] The classification of sheet goods generally includes manufactured wood products that are produced and sold in sheets such as plywood, particle board, chip board, oriented strand board, medium density fiberboard (MDF), and other forms of wood products preformed into sheets. Sheet goods, which may also include drywall, are generally sold in sheets that are four feet by eight feet and or a designated thickness, although the size can vary.
[0003] Regardless of the exact size of the sheet goods being used, problems persist. Full sheets regularly need to be cut for use. Typically, the goods are laid flat, e.g. horizontal, and the worker is required to stretch over the sheet. For instance, the cuts can be as long as the sheet, typically eight feet, requiring the worker to either stretch and have very long arms, make multiple cuts or somehow walk along the length of the goods while cutting. Workers often find it very difficult to cut at the exact place over an extended length of the cut. While electrically powered saws make the cutting relatively easy, they do little to help the accuracy and precision of the cut.
[0004] Various permanent jigs and appliances are available for use in established shops. Frequently, the sheet goods are cut using a table saw. However, the use of a table saw requires that the table saw have a large table to support the sheet, space around the table saw to move the sheet through, and that the operator lift the sheet onto the table and uniformly move the sheet through the saw blade. While this method of cutting sheet goods works quite well in an established shop, it cannot be done in the field or in a private home.
[0005] An alternative method of cutting sheets in a shop is the use of a special holding stand wherein the sheet is mounted on the stand and a track mounted saw is used to cut the sheet goods. Cutting stands of this class have been very good, but, very expensive and as such are ordinarily only used where numerous sheets must be cut on a daily basis, such as a shop manufacturing cabinets. Unless the cutting stand is being fully utilized, it is cost prohibitive to acquire.
[0006] In the prior art, when sheet goods must be cut in the field, they are cut by placing the sheet on some form of horizontal support, such as saw horses, and using a portable circular saw to cut the sheet goods. While this method does work, it is often difficult to accurately mark the cut line and even more difficult to follow the marked line. In some uses, the variance of a fraction of an inch in the cut doesn't matter or is hidden. Here the problem may not be not as great, although the stretching with power tools in operation raises safety concerns.
[0007] In other uses, it is necessary to have the cut made exactly and the cut to be straight. This creates the problem where the worker cutting the sheet of sheet goods must be very careful and particular when cutting or risk either wasting a sheet or having to spend additional time to correct the inconsistencies in the previously cut edge. This simply is not efficient.
[0008] One attempt to provide for accurate cutting of sheet goods in the field has been to use a straight piece of lumber as a straightedge to guide the cut. While this method does work, it still requires that the user place the sheet of sheet goods onto some sort of cutting stand for support and then secure the straight piece of lumber to the sheet to guide the saw for cutting. A user cannot simply hold the straightedge lumber when making a cut of four or eight feet to cut the sheet of sheet goods. The straightedge must be secured by either an assistant or being clamped. This takes time and is inefficient. Moreover, clamps tend to operate against a surface of the sheet and may cause damage thereto.
[0009] What is needed is a portable cutting stand, which is easy to assemble and disassemble, allowing easy transport. Preferably the design should have a minimum of parts and take advantage of materials already available on the job site. The clamp of the guide should further operate against an edge of the sheet goods to avoid damge to a surface, which may show in the finished product.
SUMMARY OF THE INVENTION
[0010] The invention as described herein is a portable stand that can be easily transported to a work site and assembled for use. The cutting stand provides a raised angled support table for holding the sheet of sheet goods and an alignable movable cutting guide for guiding a saw through a cut at a selected location. The cutting stand for sheet goods is provided with supports, a carriage, a guide and is used in conjunction with sheet goods.
[0011] The supports may include a foot, a lower upright and an angled upper upright portion. The lower upright is joined to the foot and the upper upright. Optionally, the upper upright may be rotationally joined to the lower upright. The support preferably includes connectors.
[0012] The carriage is joined to the supports and has horizontal members selectively received within the connectors of the supports. At least one horizontal member, desirably the lowest, can be selectively joined to sheet hooks having platforms. Sheet goods may be removably mounted on the carriage, resting on the platforms of the sheet hooks.
[0013] The guide can be movably removably joined to sheet goods. The guide, in the preferred embodiment includes a foot and a clamp joined to a straight edge. The foot has a bracket with a lip with the lip being adapted to engaged a lower edge of sheet goods. The clamp has a bracket selectively securable to a post such that the post extends through post apertures defined in the bracket. The post preferably has a hook adapted to engage an upper edge of sheet goods.
[0014] Advantageously, the present invention is a cutting stand that is simple in design, allowing lower cost and ease of storage.
[0015] Also advantageously, this cutting stand allows the user to arrange the angle at which the sheet goods are presented.
[0016] Another advantage is that the uprights join to horizontal members, minimizing the number of uprights needed to support even the longest of sheet goods.
[0017] Still another advantage is that the sheet hooks may be moved out of the way of the cutting blade and into the positions where support is most needed.
[0018] Also advantageously the sheet goods can be supported by relatively soft sacrificial wood supports that lessen the opportunity to mar the surface of the sheet of sheet goods.
[0019] Also advantageously the clamp associated with the guide operates against the edge of the sheet goods where it less likely to mar the surface of the sheet of sheet goods.
[0020] Other advantages will become clear from reading the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 is a hind prospective view showing the cutting stand with sheet goods mounted thereon;
[0022] [0022]FIG. 2 is a forward prospective view showing the carriage mounted to the uprights and the sheet hooks mounted to the lower horizontal member;
[0023] [0023]FIG. 3 is a partial view showing the guide mounted to the carriage;
[0024] [0024]FIG. 4 is a partial view showing the foot mounted to the straight edge of the guide; and
[0025] [0025]FIG. 5 is a partial view of the guide showing the clamp mounted to the straight edge.
[0026] [0026]FIG. 6 is an end view of a sheet hook shown installed over a carriage horizontal member
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] Cutting stand 10 supports sheet goods 70 for cutting. The stand 10 includes supports 12 , a carriage 30 , a guide 40 and is useable with sheet goods 70 . Each component will be described in serial fashion.
[0028] Each support 12 may include a foot 14 , a lower upright 18 and an upper upright 20 . In the preferred embodiment two supports 12 are present as additional supports 12 get in the way of the user and a single support 12 generally uses a larger than desired foot 14 and may require user interaction for stability, although such a design is plausable. The foot 14 may have any configuration. The shape shown is a cross shape with the longer portion extending rearward for support. The foot 14 may be design to disassemble for reducing package size. The upper upright 20 may be rotationally joined to the lower upright 18 with a connector 24 , allowing the user to orient the sheet goods 70 at the most desired angle for their work. Fasteners 22 , preferably C-shaped portions are joined to the support and are adapted to receive the carriage 30 .
[0029] The carriage 30 includes horizontal members 32 selectively preferably snugly received within the fasteners 22 of the supports. Suitable horizontal members 32 include any material not destructive to cutting blades such as wood or plastic. Most desirably, the horizontal members 32 are 2×4s or other 2×lumber which can be used as a sacrificial support. At least one horizontal member 32 , most desirably the lowest horizontal member 34 , may support the sheet hooks 36 . Sheet hooks 36 are adapted to support the sheet goods 70 when the stand 10 is in use. The sheet hooks 36 optionally include platforms 38 for engagement of a lower edge 74 of the sheet goods 70 .
[0030] Sheet goods 70 are used in conjunction with the stand 10 , via placement onto the carriage 30 , and upon the sheet hooks 36 where the sheet goods may be cut to a selected size. Sheet goods 70 have an upper edge 72 , a lower edge 74 and a front surface 76 . Sheet goods 70 are supported by the sheet hooks 36 and lean against the inclined carriage 30 where the sheet goods 70 are retained by gravity.
[0031] The guide 40 is an aid to cutting straight lines without the need for marking the sheet goods 70 , by resting against the front surface 76 of sheet goods 70 . Guide 40 movably mounts to sheet goods 70 and is removable therefrom. In a preferred embodiment, the guide 40 includes a foot 42 and a clamp 48 joined to a straight edge 60 . The foot 42 has a bracket 43 with a lip 44 , the lip 44 being adapted to engaged the lower edge 74 of the sheet goods 70 . Fasteners 46 such as screws or nails may be used to adhere the bracket 43 to the straight edge 60 . The straight edge 60 is preferably a straight length of 2×4 lumber selected for its straightness and cut to an appropriate length to span the chosen dimension of the sheet of sheet goods 70 to be cut.
[0032] Clamp 48 in the preferred mode has a bracket 50 selectively securable to a post 54 . The post 54 extends through post apertures 56 defined in the bracket 50 . The post 54 has a hook 58 adapted to engage the upper edge 72 of the sheet goods 70 . The post 54 selectively locks relative to the bracket 50 and the bracket 50 secures to the straight edge with fasteners 52 , such as screws or nails. The post 54 may be threaded to movably engage the post apertures 56 and similarly engage the hook 58 . The hook 58 is preferably an oval or egg shaped disk of metal or other suitable material having sufficient rigidity to selectively retain the guide 40 in a selected position. The hook 58 may also threadedly engage the post 54 .
[0033] While the previous description of the clamp 48 has described the mounting of the clamp in a vertical position to cut a sheet of sheet goods 70 to length, it is understood that by merely utilizing a longer straight edge 60 that the clamp may be clamped along the length of a sheet of sheet goods 70 and the sheet goods cut to width.
[0034] In the operation of cutting sheet goods, the user is provided at least one foot 14 joined with an upright 16 . Horizontal members 32 are selectively joined to the uprights 16 . The lower horizontal member 34 may be connected to sheet hooks 36 , which may be provided with a platform 38 . Sheet goods 70 may then be positioned on the sheet hooks 36 for cutting. In one embodiment, a guide 40 may be positioned on the sheet goods 70 , providing a straight edge to cut against, while avoiding the need to mark a cutting line thereon. Such guide can be clamped to the sheet goods 70 if desired. Such arrangement allows for easy access to large sheet goods 70 for cutting.
[0035] Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize changes may be made in form and detail without departing from the spirit and scope of the invention | A cutting stand for sheet goods including supports, each support including a foot, a lower upright joined to the foot and an angled upper support joined to the lower support; a carriage joined to the supports; sheet goods may be removably mounted on the carriage,; and a guide movably joined to sheet goods, the guide adapted to be removable from the sheet goods. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of Serial No. 645,216, filed Dec. 29, 1975 now abandoned.
BACKGROUND OF THE INVENTION
This invention is directed to a new coating composition and in particular to a new coating composition that forms a finish having an excellent appearance.
Acrylic lacquer and enamel coating compositions are well known and have been widely used to finish automobiles and trucks and also have been used to refinish and repair finishes on automobiles and trucks. One particular high quality acrylic polyurethane coating composition described in Vasta U.S. 3,558,564 issued Jan. 26, 1971 has been widely used for finishing, refinishing and repairing automobiles and trucks. However, this composition presently contains only solid colors pigments and not metallic flake pigments, such as aluminum flake pigments that provide metallic glamour to the resulting finish. When metallic flake pigments are incorporated into the above acrylic polyurethane coating composition, mottled finishes result having a low gloss and generally a poor appearance. There is a need for an acrylic polyurethane coating composition in which metallic flake pigments can be used and which gives a rapid curing high gloss non-mottling finish.
SUMMARY OF THE INVENTION
The coating composition of this invention has a solids content of 5-60% by weight and contains 95-40% by weight of an organic liquid; the solids consist essentially of
(1) 50-95% by weight of an acrylic polymer having a backbone of polymerized acrylic esters of the group of alkyl methacrylate, alkyl acrylate or mixtures thereof, each having 1-12 carbon atoms in the alkyl groups and having polymerized ethylenically unsaturated ester units that form ester groups pending from the carbon atoms of the backbone that comprise about 10 to 75% of the total weight of the polymer and are of ester group (A) ##STR1## and ester group (B) which is either ##STR2## or a mixture of these groups; wherein the molar ratio of ester group (A) to ester group (B) is from about 1:1.5 to 1:2.5; and wherein
R 1 is a saturated hydrocarbon radical having 2-4 carbon atoms
R 2 is an aromatic radical,
R 3 is a tertiary hydrocarbon group having 8-10 carbon atoms;
(2) 1-15% by weight of cellulose acetate butyrate having a butyryl content of about 50-60% by weight, a hydroxyl content of about 1.0-3.0% by weight and a viscosity of 0.02-0.5 seconds measured at 25° C. according to ASTM D-1343-56;
(3) 0.05-1.0% by weight of an alkyl acid phosphate having 1-12 carbon atoms in the alkyl group;
(4) 0.2-20.0% by weight of metallic flake pigment;
(5) 0.01-5.0% by weight of an ultraviolet light absorbing agent;
(6) 0.01-0.10% by weight of an organo metal catalyst; and
(7) 3.73-48.73% by weight of an organic polyisocyanate.
DESCRIPTION OF THE INVENTION
The coating composition of this invention contains metallic flake pigments and forms an acrylic polyurethane finish having excellent gloss, a good appearance and is not mottled. The composition has good shelf stability but cures rapidly after application.
The composition contains about 5-60% by weight of solids and about 95-40% by weight of an organic liquid. The solids of the composition are of about 50-95% by weight of an acrylic polymer, 1-15% by weight of cellulose acetate butyrate, 0.05-1.0% by weight of an alkyl acid phosphate, 0.2-20.0% by weight of a metallic flake pigment, 0.01-5.0% by weight of an ultraviolet light absorbing agent, 0.01-0.10% by weight of an organo metal catalyst, and 3.73-48.73% by weight of an organic polyisocyanate. In addition, the composition can contain 1-50% by weight of other pigments, plasticizers and other conventional additives.
The acrylic polymer and the preparation thereof is disclosed in aforementioned Vasta patent which is hereby incorporated by reference into this application. Styrene can be used in the backbone in addition to the alkyl acrylate and methacrylate constituents. One particularly useful acrylic polymer which forms a high quality finish is an acrylic polymer of styrene/methyl methacrylate/hydroxy ethyl acrylate/phthalic anhydride/a mixed glycidyl ester of synthetic tertiary carboxylic acids of the formula ##STR3## where R 3 is a tertiary aliphatic hydrocarbon of 8-10 carbon atoms; wherein the acrylic polymer has the aforementioned pendent ester groups (A) and (B) in the above molar ratio.
Any of the polyisocyanates disclosed in the above Vasta patent are useful in the composition. Generally, for exterior durability aliphatic polyisocyanates or cycloaliphatic polyisocyanates are preferred. One particularly useful polyisocyanate is the biuret of an alkylene diisocyanate having 1-6 carbon atoms in the alkylene group. One preferred polyisocyanate is the biuret of hexa(methylene)diisocyanate.
The cellulose acetate butyrate used in the composition has a butyryl content of about 50-60% by weight, a hydroxyl content of 1.0-3.0% by weight and has a viscosity of about 0.02-0.5 seconds measured at 25° C. according to ASTM D-1343-56. One preferred cellulose acetate butyrate that forms a high glamour finish has a butyryl content of 53-55% by weight and a viscosity of about 0.1-0.5 seconds and a hydroxyl content of 1.5-2.5% by weight.
The alkyl acid phosphate used in the composition has 1-12 carbon atoms in the alkyl group; preferably, the alkyl group has 2-6 carbon atoms. In prior art coating compositions the alkyl acid phosphate is used to reduce yellowing of a finish after application but in the present invention the alkyl acid phosphate is used to improve gloss of a resulting finish. Butyl acid phosphate is one preferred compound that provides a proper curing composition. One technique for preparing this preferred phosphate is to react phosphorus pentoxide with butanol giving a product that has an acid number of about 100-150. Other alkyl acid phosphates that are used are mono dialkyl acid phosphates or mixtures thereof and have an acid number of about 4-250; typical examples of these are:
methyl acid phosphate
ethyl acid phosphate
propyl acid phosphate
isopropyl acid phosphate
pentyl acid phosphate
hexyl acid phosphate
2-ethylhexyl acid phosphate
octyl acid phosphate
nonyl acid phosphate
decyl acid phosphate and
lauryl acid phosphate.
The metallic flake pigments used in the composition are any of those pigments that provide a finish with metallic glamour. These pigments include any of the conventional metallic flake pigments, such as aluminum flake, nickel flake, nickel-chrome flake, but also includes "Fire Frost" flake which is a polyester flake coated with a layer of vapor-deposited aluminum and "Afflair" pigments which are mica flakes coated with titanium dioxide. Generally, aluminum flake pigment is used. These flake pigments previously could not be used in the high quality coating compositions disclosed in the above Vasta patent without resulting in a poor appearance of the finish caused by low gloss and mottling of the finish. In the coating compositions of this invention, flake pigments are used and the resulting finishes have a good gloss and an excellent appearance.
The coating composition generally contains other conventional pigments such as metallic oxides, preferably titanium dioxide, zinc oxide, iron oxide, and the like, metallic powders, metallic hydroxides, phthalocyanine pigments such as copper phthalocyanine blue or green, quinacridones, sulfates, carbonates, carbon blacks, silica, and other pigments, organic dyes, lakes, and the like.
The coating composition contains ultraviolet light absorbing agents. Substituted benzotriazoles and benzophenones are typically useful ultraviolet light absorbing agents.
Typically useful substituted benzophenones have the structural formula ##STR4##
where X 1 , X 2 and X 3 are individually selected from the group of hydrogen, hydroxyl, alkyl, alkoxy and halogen. One particularly useful benzophenone is 4-dodecyloxy-2-hydroxy benzophenone.
Typical substituted benzotriazoles have the general formula ##STR5##
where Y, Y 1 , and Y 2 are individually selected from the group of hydrogen, hydroxyl, alkyl, and a halogen. One useful substituted benzotriazole is 2-(2'-hydroxy-5'-methyl phenyl) benzotriazole. Others are disclosed in U.S. 3,640,928, U.S. 3,004,896, and U.S. 3,189,615.
Typical organo metal catalysts used in the composition are stannous dioctoate and alkyl metal laurates, such as alkyl tin laurate, alkyl cobalt laurate, alkyl manganese laurate, alkyl zirconium laurate, alkyl nickel laurate. The alkyl group can have from 1-12 carbon atoms. Particularly useful catalysts are dibutyl tin dilaurate and stannous dioctoate.
Any of the conventional solvents can be used in the composition, such as toluene, xylene, butyl acetate, acetone, methyl isobutyl ketone, methyl ethyl ketone, and other aliphatic, cycloaliphatic and aromatic hydrocarbons, esters, ethers, ketones, and the like. These solvents also can be used to reduce the composition to an application viscosity.
The coating composition is applied by conventional techniques such as brushing, spraying, dipping, flow coating and the like, and either dried at ambient temperatures or at elevated temperatures of 50-100° C. for 2-30 minutes. The resulting acrylic coating layer is about 0.1-5 mils thick. Usually about a 1-3 mil thick layer is applied.
The composition can be applied over a wide variety of substrates such as metal, wood, glass, plastics, primed metals, or previous coated or painted metals. If used to repair an existing finish, the composition is usually applied over an acrylic primer surfacer. The composition can be applied directly to an acrylic lacquer or enamel finish that has been sanded and cleaned with an aliphatic hydrocarbon solvent. The composition can be applied as an original finish over an epoxy primer or other conventional primers or can be applied directly to bare metal. It is preferred to have the metal surface treated with a phosphate.
The following Examples illustrate the invention. The parts and percentages are by weight unless otherwise specified.
EXAMPLE 1
A coating composition is prepared as follows:
______________________________________ Parts by Weight______________________________________Portion 1Acrylic resin solution 356.15(55% solids in a solventblend of 89% ethylene glycolmonoethyl ether acetate, 11%VM and P naphtha of an acrylicpolymer of styrene/methylmethacrylate/hydroxyethylacrylate/"Cardura" E ester.sup.(1) /phthalic anhydride in a weightratio of 30/15/17/25/13 preparedaccording to Example 1 ofU.S. Pat. No. 3,558,564)Cellulose Acetate Butyrate Solution 37.01(30% solids in a solvent mixture ofethylene glycol monoethyl etheracetate ethyl acetate in a 1:7 ratioof cellulose acetate butyrate havinga butyryl content of 55% and a viscosityof 0.2 seconds measured at 25° C. accordingto ASTM D-1343-56 and a hydroxyl contentof about 1.5-2.5% by weight.)Aluminum Flake Dispersion 164.86(52% solids in a solvent blendof ethylene glycol monoethyl etheracetate/VM and P Naphtha/mineralspirits in a 77.8/10.1/12.1 ratioand aluminum flake pigment and abinder of the above acrylic resinin a pigment to binder ratio of21.2/100)Portion 2Dibutyl tin dilaurate solution 41.91(0.2% solids in ethyl acetate)U.V. Screener Solution (10%, solids 55.12in ethyl acetate of "Tinuvin" 328 U.V.absorber.sup.(2)Butyl Acid Phosphate Solution 2.50(30% solids in xylene of thereaction product of phosphorouspentoxide and butanol having anacid number of 118-143)Ethylene glycol monobutyl ether 10.90acetateEthyl acetate 77.30Portion 3VM and P naphtha 65.52Total 811.27______________________________________ .sup.(1) "Cardura" E ester (a mixed ester described in U.S. Pat. No. 3,275,583, issued Sept. 27, 1966, and is a glycidyl ester of a synthetic tertiary carboxylic acid of the formula ##STR6## where R.sup.3 is a tertiary aliphatic hydrocarbon group of 8-10 carbon atoms). .sup.(2) "Tinuvin" 328 U.V. absorber-benzotriazole of the formula ##STR7## where Y and Y.sup.1 are alkyl.
Portion 1 is charged into a mixing vessel thoroughly mixed. Portion 2 is added and mixed with portion 1 for about 1 hour. Portion 3 is added and mixed for 30 minutes.
An isocyanate solution is prepared by blending together the following constituents:
______________________________________ Parts by Weight______________________________________Ethyl acetate 451.17Solution of the biuret of hexa-methylene diisocyanate (75% 350.83solids in ethylene glycol mono-ethyl ether acetate/xylene)Total 802.00______________________________________
A sprayable coating composition is prepared by thoroughly blending 3 parts by volume of the above prepared coating composition with 1 part by volume of the isocyanate solution. The resulting composition is sprayed onto each of the following substrates:
a phosphatized steel substrate,
a steel substrate coated with an alkyd resin primer,
a steel substrate coated with an epoxy primer,
a primed steel substrate coated with an acrylic lacquer, and
a primed steel substrate coated with an acrylic enamel.
In each case the finish was dried at room temperature to provide a finish about 2-3 mils in thickness. In each case the finish has good adhesion to the substrate, good gloss and excellent metallic appearance and good chemical and water spot resistance.
EXAMPLE 2
A coating composition is prepared as follows:
______________________________________ Parts by Weight______________________________________Portion 1Ethylene glycol monobutyl 13.21ether acetateAcrylic resin solution 157.39(described in Example 1)Cellulose Acetate Butyrate 37.00solution (described in Example 1)Aluminum Flake Paste 23.08(70% solids aluminum flakepigment in mineral spirits)Portion 2Acrylic resin solution 372.42(described in Example 1)Dibutyl tin dilaurate 41.90solution (described inExample 1)U.V. Screener Solution 55.10(described in Example 1)Butyl Acid Phosphate 2.50solution (described inExample 1)Portion 3Ethylene glycol monobutyl 10.90ether acetateEthyl acetate 77.00VM and P Naphtha 65.50Total 856.00______________________________________
Portion 1 is charged into a mixing vessel thoroughly mixed for 2 hours. Portion 2 is added and mixed with portion 1 for about 1 hour. Portion 3 is slowly added and mixed for 30 minutes.
A sprayable coating composition is prepared by thoroughly blending 3 parts by volume of the above prepared coating composition with 1 part by volume of the isocyanate solution prepared in Example 1. The resulting composition is sprayed onto each of the following substrates:
a phosphatized steel substrate,
a steel substrate coated with an alkyd resin primer,
a steel substrate coated with an epoxy primer,
a primed steel substrate coated with an acrylic lacquer, and
a primed steel substrate coated with an acrylic enamel.
In each case the finish was dried at room temperature to provide a finish about 2-3 mils in thickness. In each case the finish has good adhesion to the substrate, good gloss and excellent metallic appearance and good chemical and water spot resistance. | A coating composition containing
(1) an acrylic polymer having pendent hydroxyl containing ester groups;
(2) cellulose acetate buryrate,
(3) an alkyl acid phosphate,
(4) a metallic flake pigment such as aluminum flake and, optionally other pigments,
(5) an ultraviolet light absorbing agent
(6) an organo metal catalyst, and
(7) an organic polyisocyanate;
The composition forms an excellent finish for the exterior of automobiles and trucks since the finish is glossy, durable and weatherable and has excellent metallic glamour. | 8 |
This is a continuation of application Ser. No. 539,474, filed Oct. 6, 1983, now abandoned which is a continuation-in-part of Ser. No. 516,861, filed July 25, 1983 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to staking grooves used to retain bearings and liner bushings within their receiving holes.
2. Description of the Prior Art
Staking grooves are a very common way of retaining a bearing or a bushing within a receiving hole. Commonly the bearing or bushing has formed within it adjacent its outer circumference a groove normally having an included angle of about 60°. Once the bearing or bushing is inserted into its receiving hole, some sort of tool such as a staking anvil or a center punch is forced into the staking groove to bend over at least one of the webs of metal adjacent the staking groove in order to fold this web of metal over onto a corresponding receiving beveled surface machined into an appropriate location of the receiving hole. When the staking process is done correctly, the staking serves to retain the bearing or bushing within the receiving hole by means of this crimping or folding over action of the web of metal adjacent the staking groove. Insofar as is known, however, the staking grooves utilized in the past have all been of the so-called "Grumman" type characterized by the groove having walls which are at 60° to one another. In installations of bushings or bearings which will encounter thrust loads parallel to the axis of rotation of the bearing, the Grumman groove is an inadequate retention means. This is because the relatively thick basal portion of the web of metal which is bent over does not bend as much as does the upper, thinner part of the web. This causes a radiused bend in the staked web which allows for a finite amount of creep or slippage between the outer surface of the bushing or bearing and the receiving hole. There is a clear need for an improved staking groove system in which this undesirable radiused staked web is eliminated.
The crimping or staking of the web in the staking groove can be accomplished by a number of different tools. For instance, center punches are commonly used for this purpose. More effective, however, is a specialized staking anvil which, in its normal configuration, comprises a hollow cylinder, one end of which is appropriately beveled such that when forced down into the receiving staking groove, the staking anvil will act to bend over and stake down the deformable web or webs of the staking groove in the bearing assembly or liner bushing. Unfortunately, unless the working end of the cylindrical staking anvil is exactly congruent to the configuration of the staking groove, the conventional staking anvil will work and chatter its way around, either resting predominately on the inside web of the staking groove or on the outside web of the staking groove and will not make complete contact with both web surfaces. This results in a less than desired staking action by the conventional staking anvil.
SUMMARY OF THE INVENTION
The improved staking groove of this invention is formed in a circular element such as a bearing or a bushing which is to be received within a hole, which in turn has a beveled receiving edge. The staking groove is a groove which is adjacent to the outer circumference of the circular element wherein at least the outer web, defined between the outer circumferential surface of the element and the outer surface of the groove, is formed such that its defining surfaces are parallel to each other over the majority of the web such that, when staked, the outer web conforms to the beveled receiving edge of the hole without a significant therebetween.
Additionally, the web of the staking groove may be effectively staked by use of a self-aligning staking anvil which comprises a hollow, cylindrical tool element having a working edge beveled appropriately to stake at least one web adjacent a circular staking groove to a receiving beveled surface wherein the tool element itself has a gap in its circumference perpendicular to its working edge. The gap is of sufficient width such that the working edge of the tool element may conform exactly to a variety of staking grooves requiring the same working edge bevel but different circumferences.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a typical staking groove installation, herein a liner bushing surrounding a bearing assembly;
FIG. 2 is a partial cross sectional view showing a prior art staking groove installation;
FIG. 3 is a partial cross sectional view showing the improved staking groove of the present invention;
FIG. 4 is a partial cross sectional view taken along sectional lines 1--1 of FIG. 1 showing a variation of the improved staking groove of the present invention;
FIG. 5 is a partial cross sectional view taken along sectional lines 1--1 of FIG. 1 showing another variation of the improved staking groove of the present invention;
FIG. 6 is an isometric view of the improved self aligning staking anvil useful in the practice of this invention; and
FlG. 7 is a cross sectional view showing the master matching gauge of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Turning to the drawings, FIG. 1 is an isometric view of a typical installation of a bearing assembly 14 contained within a hole in a load bearing element 10 by a bushing 12 which contains a staking groove 16, here shown as being staked down to the edge of the hole in the load receiving element 10. Section lines 1--1 are shown which will useful in succeeding drawing views.
FIG. 2 is a partial cross sectional view showing a typical prior art staking groove installation. The element 40 here inserted into the hole in the load receiving element 10 is shown with a typical prior art Grumman groove of 60°. The solid line outer web 30 formed between the outer circumferential edge of the inserted element 40 in the outer edge of the groove 26 is bent over or crimped or staked by the action of the staking anvil 24. The edge 28 of the hole has been beveled at an angle of 45°. This corresponds to the angle found on the bevel of the staking anvil 24 which is also 45°. When the staking anvil 24 is forced down into the staking groove 26, the outer web 30 is staked over as shown by the dotted line web 30. This staked web 30 then contacts the beveled edge 28 of the hole and serves to retain the inserted element 40 within the hole. However, it is important to note the dimension 32 which emphasizes the non contacted portion of the staked web 30. This dimension 32 represents the shortcomings in this prior art 60° Grumman groove in that the staked web 30 only touches the beveled edge 28 of the receiving hole in a small area. Fatigue in the staked web 30 resulting from thrust loads on the inserted element 40 will act to break loose the inserted element 40 from its receiving hole.
FIG. 3 is another partial sectional view showing the improved staking groove of the present invention. As before the inserted element 40 is received within a hole in the load receiving element 10. The edge 28 of the receiving hole is beveled as before. Also, the angle of the beveled edge 28 is here 45° corresponding to the beveled working edge of the staking anvil 24. The particular angle need not be 45° in all applications; however, this has evolved as standard practice in the industry. What is important is that the bevel angle on the staking anvil 24 corresponds to the bevel edge 28 of the receiving hole. The improved groove 42 has its outer web, defined as before between the outer circumferential edge of the inserted element 40 and the outer edge of the groove 42, shown in both solid and dotted lines as 44. The solid line web 44 corresponds to its position prior to staking and the dotted line web 44 corresponds to its position after staking. Notice that the inner and outer defining surfaces of the web 44 are parallel here. This is in marked contrast to the prior art staking groove shown in FIG. 2 is which there is a large gap in the contact between the staking web and the receiving hole edge. The inside edge of the groove 42 is inclined at an angle of about 30° relative to the circumferential edge of the inserted element 40 in applications where this inside web will not be staked. It should be noted that it is not absolutely mandatory that the inner and outer defining surfaces of the outer web 44 be exactly parallel to one another. It may be that the base of the web 44 is slightly thicker than the upper portion of the web 44. What is important is that when staked, the web 44 contacts the receiving portion of the hole along essentially all of its outer surface.
FIG. 4 is a partial cross sectional view taken along sectional lines 1--1 of FIG. 1 and shows a typical installation in which a roller bearing assembly 14 is surrounded by a liner bushing 52 which is received within a hole in a load receiving element 10. In this embodiment, the improved staking groove is slightly different than that shown in the preceding FIG. 3 in that both webs of the staking groove 51 and 53 have the substantially parallel defining surfaces since both are to be staked down onto receiving surfaces. Here the receiving surfaces are: first, on the beveled edge of the receiving hole and the load bearing element ten, and second, on the outer edge of the bearing assembly 14. Note also that the outer web 51 is shown as being slightly rolled inwardly towards the center of the groove 50. This is a common installation technique useful in all of the staking grooves discussed in this invention. Since the outer webs of the staking grooves are slightly rolled inwardly, it is much easier to insert the element which contains the staking groove into the hole in the load bearing element 10. Of course, once the various elements of the assembly 10, 52, and 14 are lined up properly, the webs 51 and 53 and their counterparts on the lower surface of the liner bushing 52 are staked down outwardly onto their respective receiving surfaces.
FIG. 5 shows another embodiment of the improved staking groove of the present invention shown here also as a partial cross sectional view taken along sectional lines 1--1 of FIG. 1. Here the bottom webs of the liner bushing 52 have been replaced with a flange 58. In this application, the liner bushing must be inserted from below. As before, the bearing assembly 14 is found inwardly of the liner bushing 56, both of which are enclosed in the hole in the load receiving element 10. The upper webs of the groove 54 are here labeled 55 and 57. Again, the webs 55 and 57 are shown as being slightly rolled inwardly to ease installation. As before, a staking anvil of some sort would be inserted into the groove after all of the elements are correctly lined up in order to stake down the webs 55 and 57 onto the respective receiving surfaces of the bearing assembly 14 and the load bearing element 10.
FIG. 6 is isometric view showing the improved self-aligning staking anvil of this invention. The improved self-aligning tool 24 is anotherwise ordinary staking anvil having a bottom working edge shown here with the beveled surfaces 62. The distinguishing characteristic of the self-aligning staking anvil 24 is that it has a gap 60 in its circumference perpendicular to the bottom working edge. The gap 60 allows the circumference of the working edge 62 of the tool 24 to conform exactly to the circumference of the staking groove upon which it will act. Variations in the circumference of the staking groove compared to the relaxed circumference of the staking anvil will be taken up by a relative opening or closing of the gap 60 to adjust the exact circumference of the tool 24 to the receiving staking groove. The prior art staking anvils are solid tools which do not include this gap. Hence, they are unable to adapt their circumferential dimension to staking grooves which have varying circumferences. Notice, however, that the beveled angle on the working edge 62 of the improved staking anvil 24 will be constant regardless of the change in circumference due to the opening or closing of the gap 60. The embodiment shown has only a single bevel to the working edge since, in the shown embodiment, only the outside web adjacent the staking groove is staked. In other applications such as those shown in FIGS. 4 and 5 wherein both webs adjacent the groove are staked, the working edge of the staking anvil will have a double bevel contour in order that both webs be staked, such that the thickness of the anvil is increased and the bevels will appear on both the inside and outside of the working edge.
In applications involving staking of liner bushings between a receiving hole and an interior bearing assembly, there is a common machining problem which results when the beveled surfaces of the receiving hole are formed. In order for the staking installation to be of optimum strength, it is necessary that the bevel on the outside edges of the bearing assembly received on the interior of the liner bushing be precisely the same as the bevels on the receiving hole to the outside of the liner bushing. If these bevels do not match reasonably precisely; that is, if the bevel on the hole is, for example, deeper than is the corresponding bevel on the bearing assembly, the staking tool will preferentially bend the web of the staking groove into good contact only with the receiving edge which has the shallower bevel. To this end, a master matching guage 64 has been developed as shown in FIG. 7. This master matching guage 64 is normally formed of thin sheet stock and is of sufficient length to completely penetrate the depth of the receiving hole. Formed into one of its longitudinal edges is a profile which matches precisely with the known profile of the bearing assembly 14 to be used in the installation. Shown in the figure are the beveled edges 65 and 69 of the bearing assembly 14 along with its own beveled circumferential outer surface 67. Matching precisely to this profile are the beveled edges 66 and 70 of the master matching guage 64 and the unbeveled edge 68. The master matching guage 64 would then be reversed by the machinist preparing the beveled surfaces on the receiving hole and used as a matching guage to precisely align the beveled surfaces between the receiving hole and the bearing assembly 14. | Liner bushings and bearing assemblies are securely captured within their receiving holes by a new staking system. The inner and outer surfaces of the webs of metal adjacent the actual staking groove which are to be bent over or staked are fabricated such that these surfaces are substantially parallel to each other over the majority of the surfaces. The staking process is advantageously accomplished by use of a self-aligning staking anvil which has a gap in its circumference in order that the tool may conform exactly to the staking groove. Additionally a master matching gauge ensures proper installation. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method of switching functions of a device, and more particularly, to a method of switching functions of a device without attaching and detaching the device.
[0003] 2. Description of the Prior Art
[0004] In Universal Serial Bus (USB) specifications, each peripheral device connected to the USB acquires an endpoint address, and communications between a mainframe and an endpoint are established through virtual pipes. Therefore, after a virtual pipe has been established, each endpoint returns a descriptor to both the USB and the mainframe (or an operating system of the mainframe) so that the mainframe perceives information related to each peripheral device. Information carried in the descriptor and related to a corresponding peripheral device includes class properties, a transmission category, a maximum package size, and a bandwidth.
[0005] For describing different types of data, different types of descriptors are required. Conventional USB descriptors include device descriptors, configuration descriptors, interface descriptors, and endpoint descriptors. Moreover, a device descriptor may be used for setting numbers of configuration descriptors, interface descriptors, and endpoint descriptors, and for setting other information. Therefore, each peripheral device has a unique device descriptor. When a specific peripheral device is required to be used, and when the peripheral device is attached to the USB, the operating system has to search for an appropriate driver for the peripheral device. At this time, a VID (Vendor Identification)/PID (Product Identification) field of the device descriptor of the peripheral device is utilized to determine an appropriate driver for the operating system, such as in a Microsoft operating system, which may include a library of installation information files having a filename extension “.inf”. While the peripheral device is attached to the USB, the Microsoft operating system has to search for an information file having a same VID/PID as the VID/PID of the descriptor of the peripheral device from among the library of installation information files, so as to find an appropriate driver for the peripheral device.
[0006] However, as variety of functions of the peripheral device grows, types of the peripheral device installed with a plurality of functions increase as well. The peripheral device having multiple functions and cooperating with the USB is conventionally called a “USB composite device.” Certain USB composite devices may not be supported by drivers provided by the Microsoft operating system, and therefore, installation of other appropriate drivers may be required to support such USB composite devices. Note that since available drivers of such USB composite devices are supplied by vendors other than the Microsoft, the available drivers may be called “vendor-supplied drivers,” whereas the drivers supplied by Microsoft are called “MS-supplied drivers.”
[0007] Please refer to FIG. 1 and FIG. 2 , both of which are schematic diagrams illustrating installation of original settings through a graphical user interface (GUI) corresponding to vendor-supplied drivers where settings of a peripheral device are conventionally required to be changed, i.e. schematic diagrams of layers between a mainframe and the peripheral device. As shown in FIG. 1 and FIG. 2 , a vendor-supplied graphical user interface (Vendor-supplied GUI) 102 is used for establishing communications between a user and an operating system 104 so that the user may manipulate operations of a USB composite device 110 . The operating system 104 is installed with MS-supplied drivers 106 and vendor-supplied drivers 108 so as to activate different functions of the USB composite device 110 . The USB composite device 110 includes a device descriptor region 112 , an additional descriptor region 114 , a reserved region 116 , a first function region 118 , and a second function region 120 . The device descriptor region 112 is installed with the device descriptor of the USB composite device 110 . The additional descriptor region 114 is installed with descriptors other than the device descriptor, such as the configuration descriptors, the interface descriptors, and the endpoint descriptors, where the descriptors installed in the additional descriptor region 114 are controlled by the device descriptor within the device descriptor region 112 . The reserved region 116 stores other information about the USB composite device 110 . Drivers currently used by the USB composite device 110 are mounted in both the first function region 118 and the second function region 120 . For example, as illustrated in FIG. 1 , a video recording driver mounted in the first function region 118 malfunctions, and an audio driver is mounted in the second function region 120 . At this time, a researcher or a user may have to remove the video recording function from the first function region 118 , and subsequently reload a video driver of an original version into the first function region 118 through either an MS-supplied driver 106 or a vendor-supplied driver 108 . However, the USB composite device 110 has to be detached and attached once from the USB at the same time. As shown in FIG. 2 , after the USB composite device 110 is re-attached to the USB, the researcher or the user may remount the original video driver by operating the vendor-supplied GUI 102 . As illustrated in FIG. 1 and FIG. 2 , though the user or the researcher may restore functions of the USB composite device 110 , i.e. the peripheral device, by removing and remounting drivers, at least one cycle of detaching and attaching the peripheral device for the USB is required, and inconveniences arise.
[0008] In certain conventional techniques, drivers may still be updated without attaching and detaching the peripheral device. In the certain conventional techniques, integrated circuits corresponding to different functions are integrated into one single integrated circuit, and the single integrated circuit is embedded into the mainframe so as to form a built-in hub. However, high fabrication costs are required in such conventional techniques, and under mass production, the conventional techniques are not attractive to common users as well.
SUMMARY OF THE INVENTION
[0009] The present invention discloses a method of switching functions of a device without attaching and detaching the device. The method is applied on a condition that the device has been attached on a universal serial bus (USB). The method comprises selecting a VID/PID according to a device selection command, a descriptor of the device, and a plurality of VID/PIDs, and selecting a driver corresponding to the selected VID/PID; determining whether the selected driver is a local driver or an external driver; activating or deactivating a function of the device through commands corresponding to the local driver while the selected driver is the local driver; determining a medium for reconfiguring the descriptor according to the device selection command; and reconfiguring the descriptor according to the activated or deactivated function. The activated or deactivated function is selected according to the device selection command.
[0010] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 and FIG. 2 are schematic diagrams of installing original settings through a graphical user interface corresponding to vendor-supplied drivers while settings of a peripheral device are conventionally required to be changed.
[0012] FIG. 3 is a flowchart of the disclosed method of switching functions of a device without attaching and detaching the device in the present invention, where the disclosed method is applied on a peripheral device attached to the USB.
[0013] FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 are diagrams illustrating a condition in which the vendor-supplied driver is determined to be the medium for switching functions of a device according to the disclosed method shown in FIG. 3 .
[0014] FIG. 8 is a diagram of a vendor-supplied GUI according to both the disclosed method shown in FIG. 3 and a preferred embodiment of the present invention.
DETAILED DESCRIPTION
[0015] For neutralizing defects including high fabrication costs and the at least one cycle of detaching and attaching the peripheral device, a method of switching functions of a device without attaching and detaching the device is disclosed in the present invention. Characteristics of the disclosed method include correlating different functions of the peripheral device (or switching different combinations of the functions) to at least one VID/PID in the device descriptor of the peripheral device, and switching the correlated functions (or switching correlated combinations of the functions) of the peripheral device by switching different VID/PIDs.
[0016] Please refer to FIG. 3 , which is a flowchart of the disclosed method of switching functions of a device without attaching and detaching the device in the present invention, where the disclosed method is applied in a peripheral device attached to the USB. As shown in FIG. 3 , the disclosed method of switching functions of the device includes steps as follows:
[0017] Step 202 : Select a VID/PID according to a device selection command, a descriptor of the device, and a plurality of VID/PIDs of the device, and select a driver corresponding to the selected VID/PID;
[0018] Step 204 : Determine whether the selected driver is a local driver or an external driver; when the driver is determined to be a local driver, go to Step 206 ; else, go to Step 214 ;
[0019] Step 206 : Activate or deactivate a function of the device through commands corresponding to the local driver when the driver is determined to be the local driver, where the activated or deactivated function is selected according to the device selection command;
[0020] Step 208 : Determine a medium for reconfiguring the descriptor according to the device selection command; when the medium is determined to be the local driver, go to Step 210 ; else, when the medium is determined to be an application program interface (API) of an operating system, go to Step 230 ;
[0021] Step 210 : Inform the device to reset through the local driver;
[0022] Step 212 : Reconfigure the descriptor according to the activated or deactivated function;
[0023] Step 214 : Activate or deactivate a function of the device through a command corresponding to the external driver while the driver is the external driver, where the activated or deactivated function is selected according to the device selection command;
[0024] Step 216 : Determine a medium for reconfiguring the descriptor according to the device selection command; when the medium is determined to be the command corresponding to the external driver, go to Step 218 ; else, when the medium is determined to be the application program interface of the operating system, go to Step 230 ;
[0025] Step 218 : Inform the device to reset through the command corresponding to the external driver;
[0026] Step 220 : Reconfigure the descriptor according to the activated or deactivated function;
[0027] Step 230 : Reconfigure the descriptor according to both the application program interface of the operating system and the activated or deactivated function; and
[0028] Step 232 : End.
[0029] Note that the device attached to the USB may be a peripheral device, which may be an image device, a mass storage device, an expansion device, or a composite device having at least two functions. When certain functions of the device malfunction, or when a user of the device tends to replace certain functions of the device, the user may initiate replacements of the certain functions of the device through a graphical user interface (GUI) provided by a vendor of the device, where the GUI is programmed according to the disclosed method of switching functions of the device in the present invention. In other words, the GUI may be regarded as a physical medium or tool for implementing a preferred embodiment of the present invention. The following descriptions are based on the above assumptions.
[0030] In Step 202 , when certain functions of the device malfunction, or when the user tends to replace certain functions of the device, the user may issue a device selection command through the GUI for making required selections while replacing functions of the device. The GUI shows a plurality of VID/PIDs of the device, enables the user to select one VID/PID from the shown plurality of VID/PIDs, and enables the user to select drivers and functions corresponding to the selected VID/PID within the device.
[0031] In Step 204 , a type of the selected driver has to be determined. Drivers related to the disclosed method of the present invention are classified into local drivers and external drivers. In a preferred embodiment of the present invention, the local driver is a driver installed on a mainframe using the Microsoft operating system, i.e. an MS-supplied driver, and the external driver is specifically provided and programmed by the vendor of the device for running the device, i.e. the vendor-supplied driver. In the following descriptions, the local driver is directly replaced by the MS-supplied driver, whereas the external driver is directly replaced by the vendor-supplied driver.
[0032] In Step 206 , when the selected driver corresponding to the selected VID/PID is determined to be an MS-supplied driver, any function of the device is activated or deactivated through a command corresponding to the MS-supplied driver, where the activated or deactivated function is also selected through the device selection command issued from the GUI and by the user. Step 208 , Step 210 , Step 212 , and Step 230 indicate a procedure of reconfiguring the descriptor of the device while the MS-supplied driver is used. In Step 208 , the device selection command is still required to determine a medium for reconfiguring the descriptor. In other words, the medium is also selected through the GUI and by the user. Step 210 indicates a condition that the user selects the MS-supplied driver as the medium for reconfiguring the descriptor so that the MS-supplied driver is used for informing the device to reset. Therefore, previous malfunctioning or unwanted settings of the device are deleted. In Step 212 , since previous settings of the device are deleted, the descriptor is reconfigured according to an activated or deactivated function selected by the user, so that settings formed from selections of the user and related to the activated or deactivated function may be applied. In Step 230 , when the user selects an API of the operating system as the medium for reconfiguring the descriptor, the API applies settings related to the activated or deactivated function on the device so as to switch required functions of the device.
[0033] In Step 214 , when the driver selected according to the selected VID/PID is a vendor-supplied driver, a command corresponding to the vendor-supplied driver is required for activating or deactivating any function of the device, where selections about activating or deactivating any function of the devices have been determined along with the device selection command. Step 216 , Step 218 , Step 220 , and Step 230 indicate the procedure of reconfiguring the descriptor of the device while the vendor-supplied driver is used. In Step 216 , the medium for reconfiguring the descriptor is also selected according to selections within the device selection command issued by the user. In Step 218 , when the command corresponding to the vendor-supplied driver is assigned as the medium for reconfiguring the descriptor, the command is used for informing the device to reset so that previous settings of the device may be completely deleted. And therefore, in Step 220 , settings related to activating or deactivating any function of the device may thus be applied on the device. Similarly, when the medium for reconfiguring the descriptor is determined to be the API of the operating system according to selections of the device selection command issued by the user, the API also applies settings related to activating or deactivating any function of the device on the device so as to switch functions of the device.
[0034] Please refer to FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 , all of which are diagrams illustrating a condition in which the vendor-supplied driver is determined to be the medium for switching functions of a device according to the disclosed method shown in FIG. 3 . Please also refer to FIG. 8 , which is a diagram of a vendor-supplied GUI according to both the disclosed method shown in FIG. 3 and a preferred embodiment of the present invention. Most elements illustrated in FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 are similar to those shown in FIG. 1 , so that repeated elements are not further described herein. Note that in the preferred embodiment of the present invention, the operating system 404 is installed with an MS-supplied audio driver 406 and a vendor-supplied image driver 408 . The following descriptions regarding FIG. 4 to FIG. 8 and the preferred embodiment of the present invention are used for more concretely explaining the disclosed method shown in FIG. 3 . Note that a vendor-supplied GUI 300 is also illustrated in the form of a block in FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 for achieving a better understanding of the preferred embodiment of the present invention.
[0035] As shown in FIG. 8 , the vendor-supplied GUI 300 includes a device selection region 302 , a driver selection region 304 , a first function setting region 306 , and a second function setting region 308 . The device selection region 302 provides functional options including “Image device”, “Mass storage device”, and “Other expansion devices”, where each of the functional options corresponds to a specific VID/PID perceived according to a device descriptor of a USB composite device 410 . The driver selection region 304 provides driver options including “Vendor A VID/PID image driver”, “Vendor B VID/PID image driver”, and “Microsoft image driver”. Note that the user is assumed to select the functional option “Image device” in the device selection region 302 , so that the driver selection region 304 merely illustrates image drivers related to the functional option “Image device”. Similarly, when the user selects a functional option “Audio device” in another embodiment of the present invention, the driver selection region 304 merely lists audio drivers related to the functional option “Audio device”. As an example, the first function setting region 306 is assumed to be used for setting a function mounted in a first function region 418 shown in FIG. 4 to FIG. 7 . Similarly, the second function setting region 308 is used for setting a function mounted in a second function region 420 shown in FIG. 4 to FIG. 7 . For example, the first function setting region 306 is assumed to turn on or turn off a video function, and the second function setting region 308 is assumed to turn on or turn off an audio function.
[0036] In FIG. 4 and Step 202 , the user performs selections on the device selection region 302 of the vendor-supplied GUI 300 shown in FIG. 8 to select a wanted type of peripheral device, and a device selection command 403 is thereby generated and issued. From FIG. 4 to FIG. 7 , options including the functional option “Image device” in the device selection region 302 , the driver option “Vendor A image driver” in the driver selection region 304 corresponding to the functional option “Image device”, the option “Turn on video function” in the first function setting region 306 , and the option “Turn off function” in the second function setting region 308 , are assumed to be selected by the user. The vendor-supplied GUI 300 also issues or generates the device selection command 403 according to the selections or settings made by the user. Note that since the device selection command 403 is issued through the vendor-supplied GUI 300 herein, the device selection command 403 at this time may be called a “vendor command.”
[0037] In FIG. 5 and Step 240 , after the operating system 404 receives the device selection command 403 , according to the selection of the functional option “Vendor A image driver”, the vendor A image driver transmits current related settings between the user and the operating system 404 to the USB composite device 410 .
[0038] In FIG. 6 and Step 214 , the USB composite device 410 replaces descriptors of both a device descriptor region 412 and an additional descriptor region 414 according to the activated or deactivated function selected in the received device selection command 403 . At this time, settings selected by the users are all completed. However, the selected settings are still required to be applied. Note that functions of the reserved region 416 are the same as those of the reserved region 116 shown in FIG. 1 , so that the functions of the reserved region 416 are not further described.
[0039] Finally, in FIG. 7 and Step 218 , since the user selects the driver option “Vendor A image driver”, the Vendor A image driver informs the USB composite device 410 to reconfigure its descriptors. Therefore, drivers other than the Vendor A image driver, i.e. the Microsoft audio driver, are removed from the operating system 404 , so that the USB composite device 410 is reset. According to the abovementioned replacements of the drivers, descriptors within both the device descriptor region 412 and the additional descriptor region 414 are reconfigured by the operating system 404 , so that functions settings related to the device selection command are applied to the USB composite device 410 . At this time, the audio function installed in the second function region 420 is also removed, so that the second function region 420 does not have any function installed.
[0040] In the preferred embodiment shown in FIG. 4 , FIG. 5 , FIG. 6 , and FIG. 7 , the updated descriptors may have the USB composite device 410 uniquely support the video function, and have the USB composite device 410 mount any vendor-supplied driver other than the MS-supplied drivers. In other words, with the aid of the vendor-supplied GUI 300 programmed according to the disclosed method of the present invention, while switching operating systems related to different platforms, an updated operating system may thus be fully supported by drivers. When an engineer needs to check or repair the vendor-supplied drivers and related functions, with the aid of the disclosed method of the present invention, required drivers and functions may be remounted or reloaded instantly. For various requirements for functions at any time, different functions of the USB composite device 410 may also be switched instantly. A most significant benefit of the disclosed method of the present invention lies in the fact that the USB composite device 410 is not required to be attached and detached to the USB entirely. Therefore, additional time-consumption is not required anymore for waiting for reconfiguration of the descriptors. Besides, expensive costs in embedding various integrated circuits related to different drivers into a built-in hub within a mainframe are also saved.
[0041] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. | According to different VID/PIDs stored in a device descriptor of a USB composite device, various functions and corresponding drivers are assigned and switched. Therefore, the switches of functions are achieved without detaching and attaching the USB composite device. Possible problems while switching operation systems of different platforms are overcome. And the high cost in embedding various drivers into a mainframe is reduced. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a system and apparatus for selecting needles for patterning, in a multifeed circular knitting machine.
Multifeed circular knitting machines are provided with a needle cylinder having a plurality of vertical parallel grooves in each of which is slidably located a needle which is adapted to move, according to a predetermined pattern, in cooperation with other needles or sinkers to form loops of yarn fed to them, from feeds spaced about the cylinder. The selection of the appropriate needle and the control of its movement is conventionally provided by locating one or more selectors and/or jacks within the groove which may be controlled to swing into and out of engagement with a cam system to effect transfer of the needle into operating position and which in cooperation with the cam system cause the needle to vertically reciprocate into either the closing or tucking position or not move at all. The primary movement of the needles is generally initiated by selection of an upper selector jack in abutment with the needle while the auxiliary selection is initiated by a lower selector jack. Patterning means are provided which are actuable in accord with the patterning system to independently control (i.e. select) the appropriate selector jacks and/or the sinker selecting system. The selectors are generally rockable within the groove, as well as slidable so that the patterning means is capable of swinging the selectors into and out of its respective cam system whereby vertical reciprocation is obtained. The selector jacks are normally pressed or swung back into their original positions (i.e. inoperative) after or behind the yarn feed in which they lifted the needles into knitting position.
Although this system is reliable in its operation, it requires considerable space about the circumference of the needle cylinder for each feed system. Thus if its is necessary, in each feed system to perform a new needle selection then it is impossible with the foregoing system to employ a plurality of feeds, particularly if the machine lies intermediate a large and small diameter.
An object of the present invention is to provide a selection system which overcomes and/or mitigates the aforementioned disadvantages and which provides a simple and reliable system for plural needle selection in multifeed circular knitting machines.
The foregoing objects as well as others together with the numerous advantages of the present invention will be found in and are set forth in the following disclosure.
SUMMARY OF THE INVENTION
According to the present invention a multifeed knitting machine is provided having a needle cylinder in which a plurality of needles are mounted in respective grooves and are each displaceable into knitting positions in cooperation with a sinker or opposed needle by a cooperating cam system, and a needle selecting system. The needle selecting system comprises a pair of rockable selector jacks mounted in tandem in each needle groove below the needle retained therein, the adjacent ends of which are formed with butts engageable selectively by projecting elements of a pattern wheel mounted adjacent the needle cylinder, which cause the selector jacks to engage appropriate paths in the cam system thus displacing the needle. The cam system is arranged with surfaces which push back the selector jacks into their original position, which surfaces are formed in front of the clearing point for each yarn feed.
Full details of the present invention are set forth in the following disclosure and are illustrated in accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a partial sectional view of the needle cylinder of a multifeed knitting machine and a planar development of the associated cam system;
FIG. 1a is an isometric view of the retracting cam employed in the system of FIG. 1;
FIG. 2 is a partial sectional view of the needle cylinder of FIG. 1 illustrating the position of the patterning wheel in position to select the lower selector jack; and
FIG. 3 is a view similar to FIG. 2 in position to select the upper selector jack.
DESCRIPTION OF THE INVENTION
In the drawing a multifeed circular knitting machine is depicted showing only those conventional portions necessary for an understanding of the present invention. Portions of conventional structure and function are not shown.
As seen in the figures, a needle cylinder 1, rotatable about its central axis in the direction indicated by the arrow S is provided with a plurality of longitudinally extending parallel grooves 2 in each of which a needle 3 is mounted so as to be reciprocably movable therein. Each needle is provided with a control butt 30. Mounted in each groove below the needle is a first rockable selecting jack 4 below which is mounted a second rockable selecting jack 5. The selecting jacks 4 and 5 are also reciprocably movable in the groove, and have an inner edge which is in at least two portions, set at angles to each other to define a pivot point about which the respective jack rocks.
The needles 3 cooperate to form loops with known, not shown, sinker elements 3a, arranged at the upper end of the needle cylinder. The yarn is laid in feeds by means of conventional yarn guides, of which the machine is provided with several. Surrounding the exterior of the needle cylinder is a control cam system provided with cam means by which the sinkers, needles and jacks are caused to reciprocate in the prescribed knitting pattern. At each of the yarn feeds the cam system is provided with a sinker cam 8 and a needle trough 9 which defines a cam path b in which the needle butt 30 rides when not selected and a path b' in which the needle moves, when it, ie: the needle, is selected. The clearing point or terminus of cam 8 is illustrated by the vertical lines.
The vertical movement of the selector jacks, controlling the selection of the needle is also effected by the cam system. Selector jack 4 provided with a control butt 4', which when the jack is selected is caused to engage on the upper edge of rising cams 10, each having an upwardly inclined edge 100, which is arranged in such a manner to have a path a which causes the jacks 4 to move upwardly in the space of each feed, between the clearing points with each of its adjacent feeds. At the end of each upwardly inclined edge 100 of each cam 10 is a laterally extending inclined retracting edge 101 which causes the jack 4 to be pushed back allowing it to descend into the next succeeding cam 10. The lower selector jacks 5 are moved in a path c, in the same manner, by engagement of its control butt 5' in a set of cams 11, each cam 11 having a rising edge 110 and an inclined surface 111, which extends laterally outward from the plane of the cam system. In order to retract the lifted selectors 5, sinker cams 12 having clearing edges 120 are arranged cooperatively above the cam 11. The cam 11 and 12 are distributed with respect to the feed systems in a similar manner and position as are cams 10.
The engagement of the selectors 4 and 5 with their respective cams is effected by a pattern selection system in which a rotating patterning wheel 6 (FIG. 2) is arranged adjacent the exterior of the needle in the section A of the cam system (FIG. 1) immediately after the clearing point of each of cams 8. The wheel 6 is mounted to rotate at a speed identical with that of the needle cylinder and is provided with one or more extending elements which selectively engage the butt formation 40 or 50 formed respectively on the adjacent ends of the selecting jacks 4 and 5. The selecting elements may be either cams, pins or comb. The patterning wheel 6 may be replaced with a drum, disk stack or similar selecting means such as a solenoid or press button system, which may be automatically controlled, as is known.
In operation, the selection of selectors 4 and 5 is carried out by the patterning wheel 6 located in the section A immediately behind the clearing point of cam 8 of the preceeding feed. If the selecting means 7 on the patterning wheel 6, is in the position as shown in FIG. 3, the lower butts 40 of selector jack 4 is pushed back into groove 2 of needle cylinder 1 forcing butt 4' into path a so that the recess 24 contacts rising cam 10. The selector jack 4 is thus lifted by lifting edge 100, as represented by path a. Simultaneously, selector jack 4 lifts needle 3 as far as its clearing position, as represented by path b' of butt 30, in which yarn is laid into needle 3, a plain loop being formed by clearing on cam 8. The selector jack 4, or its upper butt 4' respectively following in its uppermost position the path a, contacts the inclined surface 101 and is pushed back to its original position as shown in FIG. 1. Upon further rotation of needle cylinder 1, the selector jack 4 is cleared back into its lower position by needle 3 which engages the cam 8 and forces downwardly on the selector jack 4 preparing it for another feed. During the procedure as specified above, the lower selector 5 passes through the lower position as shown in FIG. 1, in inactive status.
When the selection element 7 on the patterning wheel 6 is in the position as shown in FIG. 2, the upper butt 50 of selector 5 is pushed into groove 2 of needle cylinder 1 and the recess 25 formed at the lower end of the selector jack 5 contacts the rising cam 11. Selector jack 5 is thus lifted by rising edge 110, as represented by path c. The selector 5 is in contact with selector 4 and lifts the latter, which in turn lifts needle 3 as far as its tucking position, in which butt 30 of needle 3 follows path d and yarn is laid into the needle, a tuck loop being formed by clearing on cam 8. During laying yarn into the needle, the lower end of selector jack 5 contacts the inclined surface 111 and is pressed into its original position, and upon further rotation, selector jack 5 is drawn by its butt 5' along path a by sinker edge 120 of cam 12. Upon the following clearing of the needle by cam 8, selector 4 is cleared by needle 3 into its original position.
When no selection takes place, needles 3 and selector jacks 4 and 5 pass through their lower positions and no loops are formed.
By the procedure as specified above, needles 3 are selected into two operative positions in all feeds with a single arranged patterning wheel 6. The advantage of the present invention consists in that, selection into operative positions as well as clearing of displaceable elements in the grooves of a needle cylinder in a narrow angular section thereof is performed by simple means, thus making possible to distribute about the circumference a plurality of feeds.
As will be seen from the foregoing, a simple, reliable system is provided which enables the transfer of the needles into more than one position for each yarn feed, and which provides that retraction of the needle and the selector jacks before clearing of the needle. The system and the apparatus therefore is small and free of complex mechanisms so that it may be incorporated in most circular knitting machines without extensive modification or rebuilding of the machines.
Various modifications and changes have been suggested in the foregoing description. Others will be obvious to those skilled in this art. Consequently, it is intended that the present disclosure be illustrative only and not limiting of the scope of the invention. | A needle selecting system having a pair of rockable selector jacks mounted in tandem in each needle groove below the needle retained therein. The adjacent ends of the jacks are formed with butts engageable selectively by projecting elements of a pattern wheel mounted adjacent the needle cylinder, which causes the selector jacks to engage in appropriate paths in the cam system, thus displacing the needle. The cam system is arranged with surfaces which push back the selector jacks into their original position, which surfaces are formed in front of the clearing point for each yarn feed. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is a National Phase patent application and claims priority to and the benefit of International Application Number PCT/CN2014/086538, filed on Sep. 15, 2014, which claims priority to and the benefit of Korean Patent Application Number 201310433018.6, filed Sep. 22, 2013, the entire contents of all of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to the field of medicine. Particularly, the present invention relates to a novel compound having an activity of S1P1 receptor agonists, a pharmaceutical composition comprising the compound, use of the compound and pharmaceutical composition for manufacturing a medicament for the treatment of disease mediated by S1P1 receptor and use of the compound and pharmaceutical composition for treating related disease mediated by S1P1 receptor.
BACKGROUND OF THE INVENTION
[0003] It is well known in the art that the presence of sphingosine-1-phosphate receptor-1 (S1P1) is required for the transport of lymphocytes from lymphatic tissues into the peripheral circulation. However, internalization of S1P1 may prevent lymphocytes from exiting lymphatic tissues, and thus those important immunocytes will be confined in lymphatic tissues.
[0004] Many studies suggested that there exist multiple S1P1 agonists which can bind to homologous receptors expressed on lymphocytes and result in the internalization of S1P1, thereby preventing the transport of lymphocytes. S1P1 receptor agonists can reduce the ability of human to initiate immune response by preventing the transport of lymphocytes, therefore they could serve as immunosuppressants for the treatment of various autoimmune diseases.
[0005] Many S1P1 agonists have been described and the most typical compound among them is FTY720 (also known as “Fingolimod”). Now, FTY720 is promoted and sold by Novartis under a trade name “Gilenya”, for the treatment of Multiple sclerosis. Although FTY720 has clinical efficacy, it is a non-selective S1P receptor agonist and may activate several S1P receptors, such as S1P1, S1P2, S1P3, S1P4, and S1P5. The binding of FTY720 to S1P3 may result in a series of side effects, for example, bradycardia and tissue fibrosis. Therefore, many pharmaceutical companies and biotechnology groups are searching for the second generation of S1P1 agonist which is more specific and safer, so as to overcome the side effects of FTY720.
[0006] In addition to improving target specificity, shortening the in vivo half-life of drug (i.e. S1P1 receptor agonist) is another important object of screening the second generation of S1P1 agonist (Pan et al., 2013, ACS Medicinal Chemistry Letters, 4, p333). Traditionally, small molecule drugs with longer half-life are considered to be desirable, since a long half-life can avoid frequent administration of the drug. However, a long half-life may become a severe disadvantage for immunosuppressant drugs because the immunosuppressant drug may persistently inhibit the transport of lymphocytes, and thus decrease the number of lymphocytes in the peripheral blood, resulting in a reduced immune functioning and an increased risk of viral infections for drug users. The disadvantage above exists with S1P1 receptor agonist, such as FTY720, clinically used at present. In case of infection, it is often required to discontinue administration, in order to get lymphocytes in the peripheral blood return to a normal level as soon as feasible and restore the immune function of human body rapidly. As the half-life of FTY720 in the body is 6 to 9 days, a long time is needed for lymphocytes to revert to normal even after patients stop taking the medicine (Budde et al., 2002, Journal of the American Society of Nephrology, 13:1073-83).
[0007] Therefore, there is still a need for a novel S1P1 receptor agonist with high selectivity for S1P1 and a shorter half-life, to overcome deficiencies of the existing therapies.
SUMMARY OF THE INVENTION
[0008] In order to solve the technical problems above, the inventors carried out pharmaceutical chemical synthesis, and screened a large number of synthesized compounds through pharmacokinetic studies in rats in combination with studies on immune cell regulation and the like. It was found during the studies that novel compounds can be obtained by addition of halogen or alkyl to position 2 in compound as shown in Formula IA, which has been described as 1-{4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Li et al., 2005, Journal of Medicinal Chemistry, 48 (20) 6169-6173; also known as “Compound 1” herein). Those compounds retained the potency of immune regulation in vitro and in vivo after intravenous and oral administration, and additionally the obtained compounds through substitution by halogen also have obviously reduced half-life after being administered in the two different ways.
[0000]
[0009] Therefore, one purpose of the present invention is to provide a novel compound, to solve the deficiency in selectivity and half-life of existing S1P1 receptor agonists. Another purpose of the present invention is to provide a use of the compound for manufacturing a medicament. Yet another purpose of the present invention is to provide a pharmaceutical composition comprising the compound as major active ingredient. Still another purpose of the present invention is to provide a method for treating disease using the compound or the pharmaceutical composition. Still yet another purpose of the present invention is to provide a synthesis method of the compound.
[0010] In order to realize the above purposes, technical solutions provided by the present invention are as follows:
[0011] In one aspect, the present invention provides a compound as shown in Formula I,
[0000]
[0000] wherein, R is halogen or C 1 -C 6 alkyl.
[0012] Preferably, R is F, Cl or Br; or R is C1-C3 alkyl, more preferably methyl.
[0013] The compound is, when R is F, 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (also known as “Compound 2” herein), which is represented by Formula IB:
[0000]
[0014] The compound is, when R is Cl, 1-{2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (also known as “Compound 3” herein), which is represented by Formula IC:
[0000]
[0015] The compound is, when R is Br, 1-{2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (also known as “Compound 4” herein), which is represented by Formula ID:
[0000]
[0016] The compound is, when R is methyl, 1-{2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (also known as “Compound 5” herein), which is represented by Formula IE:
[0000]
[0017] A large number of experiments showed that the compounds provided by the present invention had S1P1 agonistic activity, which was confirmed by the detected internalization of S1P1 and the reduced number of lymphocytes in the peripheral blood induced by the compounds. Meanwhile, the compounds provided by the present invention also had selective specificity for S1P1; especially the compounds did not induce cells expressing S1P3 subtype to internalize. Further, pharmacokinetic experiments of the compounds provided by the present invention showed that, the half-life of certain compounds was shortened significantly compared to that of compound represented by Formula IA, and was much shorter than that of FTY720.
[0018] Therefore, in another aspect, the present invention provides a use of above compounds for manufacturing a medicament for the treatment of disease or condition mediated by S1P1. Particularly, said disease or condition is selected from the group consisting of rheumatoid arthritis, multiple sclerosis, inflammatory enteritis, autoimmune disease, chronic inflammatory disease, asthma, inflammatory neuropathies, arthritis, transplantation, Crohn's disease, ulcerative colitis, lupus erythematosus, psoriasis, ischemia-reperfusion injury, solid tumor, disease associated with angiogenesis, disease of blood vessel, pain, acute viral disease, inflammatory bowel disease, insulin and non-insulin dependent diabetes mellitus, and other related immune diseases. Preferably, said disease or condition is selected from the group consisting of multiple sclerosis, rheumatoid arthritis, inflammatory enteritis and psoriasis.
[0019] As used herein, expression “treating” or “treatment” also refers to preventing above diseases or conditions or delaying symptoms and the like, apart from curing diseases or conditions mediated by S1P1.
[0020] In yet another aspect, the present invention provides a pharmaceutical composition comprising the compound provided by the present invention and optionally a pharmaceutically acceptable carrier. The pharmaceutical composition can be a medicinal formulation itself, or can be prepared as a medicinal formulation or a combined medicinal formulation with other excipient(s) or drug(s).
[0021] Specifically, the pharmaceutical composition provided by the present invention may be in a form of tablet, suppository, dispersible tablet, enteric-coated tablet, chewable tablet, orally disintegrating tablet, capsule, sugar-coated agent, granule, dry powder, oral solution, small needle for injection, lyophilized powder or large volume parenteral solution for injection; wherein, the pharmaceutically acceptable excipient may be selected from the group consisting of diluents, solubilizers, disintegrating agents, suspending agents, lubricants, binders, fillers, flavoring agents, sweeteners, antioxidants, surfactants, preservatives, wrapping agents and pigments, etc.
[0022] In still another aspect, the present invention provides a method for treating disease or condition mediated by S1P1, comprising administering to a subject a therapeutically effective amount of the compound or the pharmaceutical composition of the present invention. Preferably, said subject is a mammalian.
[0023] Wherein, said disease or condition is selected from the group consisting of rheumatoid arthritis, multiple sclerosis, inflammatory enteritis, autoimmune disease, chronic inflammatory disease, asthma, inflammatory neuropathies, arthritis, transplantation, Crohn's disease, ulcerativecolitis, lupus erythematosus, psoriasis, ischemia-reperfusion injury, solid tumor, disease associated with angiogenesis, disease of blood vessel, pain, acute viral disease, inflammatory bowel disease, insulin and non-insulin dependent diabetes mellitus, and other related immune diseases. Preferably, said disease or condition is selected from the group consisting of multiple sclerosis, rheumatoid arthritis, inflammatory enteritis and psoriasis.
[0024] The compound or pharmaceutical composition provided by the present invention can be co-administered with other therapies or therapeutic agents. What's more, doses of the compound or pharmaceutical composition needed for playing the role of treatment, prevention or delay depend on the particular compound to be administered, patient, specific disease or disorder and severity thereof, route and frequency of administration and so on, and need to be determined by the attending doctor in accordance with specific conditions.
[0025] In summary, the present invention provides a novel compound having an activity of S1P1 agonists, and the compound is obtained by substituting at position 2 in the compound represented by Formula IA with halogen, especially fluorine, chlorine or bromine or lower alkyl. It can be proven that the compounds of the present invention have the activity of S1P1 agonists by the experimentally detected internalization of S1P1 and the reduced number of lymphocytes in the peripheral blood. In addition, internalization induction experiments using cells expressing S1P3 subtype also prove that the compounds have a selective specificity for S1P1.
[0026] In particular, compared with known S1P1 agonists and the compound as shown in formula IA, the compounds of the present invention obtained through substitution with halogen have significantly shortened half-life. Pharmacokinetic experiments proven that the half-life of those compounds was shortened significantly from about 11 hours to less than 5.5 hours. Both intravenous and oral administration modes showed a significantly shortened half-life, which was consistent with the reduced parameter of mean residence time. What's more, it is inventive to substitute with specific substituents at specific positions. Moreover, although the half-life of the compound obtained by substituting at the same position with a lower alkyl, especially with methyl (Compound 5), is not shortened, the effects on lymphocytes in vivo are similar to those of compounds substituted with halogen. These results indicate that the compounds provided by the present invention are potential qualified second generation of S1P1 agonist.
[0027] In still yet another aspect, as for the compound represented by Formula IB (Compound 2), the present invention further provides a synthesis method which involves simple reaction conditions, and is convenient to post-treatment and suitable for industrialized manufacture with a high yield and stable process.
[0028] In short, the synthesis scheme of the present invention is as follows:
[0000]
[0029] Specifically, the present invention provides a synthesis method of 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (also known as “Compound 2”) as shown in Formula IB, comprising the following steps:
[0000] (1) reacting 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine as shown in formula 1-3 with 4-isobutylbenzoicacid as shown in formula 1-4 in the presence of condensation agents 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 1-hydroxybenzotrizole to generate the 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol as shown in formula 1-5:
[0000]
[0000] (2) reacting the 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol of formula 1-5 obtained in step (1) with manganese dioxide to generate 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde as shown in formula 1-6:
[0000]
[0000] (3) reacting the 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde as shown in formula 1-6 obtained in step (2) with azetidine-3-carboxylic acid as shown in formula 1-7 by using acetic acid as catalyst and sodium cyanoborohydride as reducing agent to generate the compound as shown in formula IB:
[0000]
[0030] According to preferred embodiments of the present invention, step (1) also comprises a step of purifying the obtained crude product after the generation of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol as shown in formula 1-5; preferably, the purification is conducted through column chromatography or crystallization.
[0031] When conducting purification through crystallization, the crystallization solvent utilized is one or more selected from methanol, ethanol, acetone, dichloromethane, ethyl acetate, and water; preferably, the crystallization solvent is a mixture of methanol and water; more preferably, the crystallization solvent is a mixture of methanol and water in a ratio of 3:1 by volume. Preferably, the ratio of the crude product (in g, by weight) to the crystallization solvent (in ml, by volume) is 1:3-20, more preferably 1:5. Preferably, the crystallization is carried out at 20° C.
[0032] According to preferred embodiments of the present invention, the reaction of step (1) is carried out in a reaction solvent which is one or more selected from acetonitrile, N-methylpyrrolidone and N,N-dimethylformamide; the reaction is conducted at a temperature of 80-140° C.; and the mole ratio of 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine as shown in formula 1-3 to 4-isobutyl benzoicacid as shown in formula 1-4 is 1:1-2.0.
[0033] Preferably, in step (1), the reaction solvent is N,N-dimethylformamide;
[0000] preferably, the reaction temperature is 130-140° C.; and
preferably, the mole ratio of 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine as shown in formula 1-3 to 4-isobutyl benzoicacid as shown in formula 1-4 is 1:1-1.5, more preferably 1:1-1.2.
[0034] According to preferred embodiments of the present invention, the reaction of step (2) is carried out in a reaction solvent which is one or more selected from toluene, tetrahydrofuran and ethyl acetate; the ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol as shown in formula 1-5 (in g, by weight) to the reaction solvent (in ml, by volume) is 1:10-30; the reaction is conducted at a temperature of 40-70° C.; and the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol as shown in formula 1-5 to manganese dioxide is 1:4-10.
[0035] Preferably, in step (2), the reaction solvent is ethyl acetate;
[0000] preferably, the ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol as shown in formula 1-5 (in g, by weight) to the reaction solvent (in ml, by volume) is 1:10;
preferably, the reaction temperature is 60-70° C.; and
preferably, the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol as shown in formula 1-5 to manganese dioxide is 1:5-6, more preferably 1:6.
[0036] According to preferred embodiments of the present invention, the reaction of step (3) is carried out in a reaction solvent which is selected from tetrahydrofuran and/or methanol; the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde as shown in formula 1-6 to azetidine-3-carboxylic acid as shown in formula 1-7 is 1:1-1.2; the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde as shown in formula 1-6 to sodium cyanoborohydride is 1:0.5-6; the reaction is conducted at a temperature of 0-30° C. for a reaction period of 1-16 hours.
[0037] Preferably, in step (3), the reaction solvent is methanol;
[0000] preferably, the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde as shown in formula 1-6 to azetidine-3-carboxylic acid as shown in formula 1-7 is 1:1-1.1, more preferably 1:1;
preferably, the sodium cyanoborohydride is dissolved in methanol and dropped into the reaction system at a temperature of 0-20° C., more preferably 15-20° C.;
preferably, the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde as shown in formula 1-6 to sodium cyanoborohydride is 1:1;
preferably, the reaction temperature is 10-20° C., more preferably 15-20° C.; and
preferably, the reaction period is 4-16 hours.
[0038] In step (1) of synthesis method of the compound represented by formula IB (compound 2) provided by the present invention, the purification of the intermediate crude product is preferably conducted with crystallization, rather than column chromatography. The purification operation will be simplified and the use of large amounts of solvents will be avoided by abandoning column chromatography which needs large amounts of solvents, is less friendly to the environment and has a higher cost. Meanwhile, the reactants, solvents and the amounts thereof used in each step of the method provided by present invention are also adjusted. For example, in step (2), a reduced amount of manganese dioxide can be used for decreasing the cost; and it is ethyl acetate, rather than tetrahydrofuran, used as the reaction solvent for avoiding safety risk that may arise. In step (3), methanol is used as the reaction solvent, which can reduce by-product generation during the reaction, increase the yield of the reaction and reduce the amount of the solvent used in the reaction. Generally speaking, cost is decreased and manufacture on a large scale with a low cost, and high efficiency and safety level is realized through those improvements.
[0039] All publications, including but not limited to patents and patent applications cited in this specification are herein incorporated by reference as if each individual publication were specifically and individually indicated to be incorporated by reference herein as though fully set forth.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings in detail, wherein,
[0041] FIGS. 1A and 1B show results from pharmacokinetic experiments of the compounds provided by present invention in Example 6, with FIG. 1A showing data on drug concentration in vivo varied over time in rats after compound 2, 3 and 4 were administrated orally, and FIG. 1B showing data on drug concentration in vivo varied over time in rats after compound 1 and 5 were administrated orally.
[0042] FIG. 2 shows experimental results of Example 8, which showed the number of lymphocytes in the peripheral blood was reduced by compound 2 of the present invention.
[0043] FIG. 3 shows experimental results of Example 8, which showed the number of lymphocytes in the peripheral blood was reduced by compounds 3 and 4 of the present invention, wherein compounds 3 and 4 were administered at 0.1 mg/kg body weight into rats.
[0044] FIG. 4 shows experimental results of Example 8, which showed the number of lymphocytes in the peripheral blood was reduced by compound 5 of the present invention, wherein compound 5 was administered at 0.1 mg/kg body weight into rats.
[0045] FIG. 5 shows experimental results of Example 9, which showed the development of arthroncus in arthritis was inhibited by compound 2 provided by present invention.
[0046] FIG. 6 shows experimental results of Example 9, which showed the damage of joint structure in arthritis was inhibited by compound 2 provided by present invention.
[0047] FIG. 7 shows experimental results of Example 10, which showed the development of EAE was inhibited by compound 2 provided by present invention.
[0048] FIGS. 8A to 8C show experimental results of Example 11, which showed the effect of compound 2 provided by present invention on electrocardiographic index.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0049] The present invention will be further described in detail in combination with the embodiments hereinafter. It will be appreciated by those skilled in the art that the embodiments provided are only used to illustrate the present invention, rather than limiting the scope of the present invention in any way.
[0050] Experimental methods in the following embodiments, if no any other special instruction is provided, are all conventional methods. Raw materials, reagents and other materials used in the following examples, if no any other special instruction is provided, can be commercially available.
Example 1
Synthesis of 1-{4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 1)
1.1 (Z)—N′-hydroxy-4-hydroxymethyl benzamidine (1-3)
[0051]
[0052] Hydroxylamine hydrochloride (1-2, 20.903 g, 300.76 mmol) and sodium bicarbonate (50.5 g, 601.5 mmol) were added successively to a solution of 4-hydroxymethyl benzonitrile (1-1, 20 g, 150.38 mmol) in methanol (250 mL) to obtain a suspension which was then heated to reflux for 5 hours. It was then cooled down to room temperature and filtered. The filter cake was washed with methanol (100 mL), and the obtained filtrate was concentrated to obtain (Z)—N′-hydroxy-4-hydroxymethyl benzamidine which was a white crude product (1-3, 24.8 g of the crude product, 99.3% yield), which was directly used in the next step. The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 167.3 [M+H] + . NMR: 1 HNMR (400 MHz, CD3OD) δ: 7.64 (d, J=8.0 Hz, 2H), 7.40 (d, J=8.0 Hz, 2H), 4.65 (s, 2H).
1.2 4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5)
[0053]
[0054] At room temperature, a solution of 4-isobutyl benzoic acid (1-4, 26.6 g, 149.4 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI, 28.685 g, 149.4 mmol) and 1-hydroxybenzotrizole (20.169 g, 149.4 mmol) in N,N-dimethylformamide (200 mL) was stirred for 30 min before the addition of (Z)—N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 24.8 g, 149.4 mmol). The obtained mixed system was heated in 140° C. oil bath for 2 hours. LC-MS indicated that the reaction was complete. It was then cooled down to room temperature and most of N,N-dimethylformamide was removed by distillation under reduced pressure. The reaction system was extracted with water and ethyl acetate, and the obtained organic phase was washed successively with 0.5N HCl solution, saturated NaHCO 3 solution and water, dried with anhydrous sodium sulfate and filtered, then the filtrate was concentrated to dryness. The residue was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=10/1−4/1) to obtain 4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was a white solid product (1-5, 34.5 g, 75% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 309.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.16 (d, J=8.4 Hz, 2H), 8.12 (d, J=8.4 Hz, 2H), 7.51 (d, J=8.4 Hz, 2H), 7.33 (d, J=8.4 Hz, 2H), 4.79 (d, J=5.2 Hz, 2H), 2.57 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 1.85 (t, 1H), 0.97 (d, J=7.2 Hz, 6H).
1.3 4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6)
[0055]
[0056] At 60° C., a suspension system of 4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 17.7 g, 57.5 mmol) and manganese dioxide (50 g, 575 mmol) in tetrahydrofuran (330 mL) was stirred for 2 hours. Then the suspension system was cooled to room temperature, filtered and concentrated to dryness. The residue was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=20/1) to obtain 4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 16.44 g, 93.5% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 307.2 [M+H] + .
2. 1-{4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid
[0057]
[0058] At room temperature, a solution of 4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 10 g, 32.7 mmol), azetidine-3-carboxylic acid (1-7, 3.63 g, 36 mmol) and acetic acid (15 mL) in methanol-tetrahydrofuran (200 mL/200 mL) was stirred for 2 hours. Then a solution of sodium cyanoborohydride (1.03 g, 16.35 mmol) in methanol (60 mL) was added to the reaction mixture and the resulting mixture was stirred at room temperature for additional 16 hours and filtered. The filter cake was washed with methanol (90 mL) and then dried to obtain 1-{4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (5.5 g; reduction product 1-5 from compound 1-6 was collected, and then oxidized and reductive aminated to obtain 5 g final product; 82% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 392.2 [M+H] + . NMR: 1 HNMR (400 MHz, CD3OD) δ: 8.23 (d, J=8.4 Hz, 2H), 8.15 (d, J=8.0 Hz, 2H), 7.64 (d, J=8.4 Hz, 2H), 7.44 (d, J=8.0 Hz, 2H), 4.34 (s, 2H), 4.12 (m, 4H), 3.42 (m, 1H), 2.63 (d, J=7.2 Hz, 2H), 1.97 (m, 1H) 0.97 (d, J=7.2 Hz, 6H).
Example 2
Synthesis of 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 2)
[0059]
1.1 4-bromo-2-fluorobenzyl alcohol (1-1)
[0060]
[0061] At 0° C., lithium aluminum hydride (1.14 g, 30 mmol) was dropped into a solution of Methyl 4-Bromo-2-fluorobenzoate (4.66 g, 20 mmol) in tetrahydrofuran (100 mL) slowly. The ice-salt bath used was removed after that dropping. The reaction was complete (detected by LCMS and TLC) after stirred for 1 hour at room temperature. The mixture was cooled to 0° C. again and the reaction was quenched with water (1.14 mL) and 10% NaOH solution (11.4 mL) respectively. After stirred for 15 min at room temperature, the mixture was filtered and then the filter cake was washed with tetrahydrofuran (50 mL×2) and ethyl acetate EA (50 mL×2). The filtrate was dried with anhydrous sodium sulfate, filtered, and then concentrated to obtain a colorless oil product (3.4 g, 83% yield).
1.2 3-fluoro-4-hydroxymethyl benzonitrile (1-2)
[0062]
[0063] Zinc cyanide (1.85 g, 15.85 mmol) and tetrakis(triphenylphosphine) palladium (Pd(PPh 3 ) 4 , 0.916 g, 0.79 mmol) were added into a solution of 4-bromo-2-fluorobenzyl alcohol (1-1, 3.25 g, 15.85 mmol) in DMF (35 mL). After deoxygenated via argon bubbling, the reaction mixture was heated at 100° C. and reacted for 16 hours, cooled down to room temperature, diluted with ethyl acetate (100 mL), washed successively with water (100 mL×3) and saturated brine (100 mL×3), dried with anhydrous sodium sulfate and filtered. The filtrate was concentrated to obtain a crude product. The crude product was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=15/1−4/1) to obtain a white solid product (0.72 g, 30% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 152.1 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 7.63 (t, J=7.6 Hz, 8.0 Hz, 1H), 7.48 (dd, J=1.2 Hz, 8.0 Hz, 1H), 7.48 (dd, J=1.2 Hz, 9.2 Hz, 1H), 4.83 (d, J=10 Hz, 2H), 2.00 (t, J=10 Hz, 1H).
1.3 (Z)-3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3)
[0064]
[0065] Hydroxylamine hydrochloride (0.645 g, 9.28 mmol) and sodium bicarbonate (1.56 g, 18.56 mmol) were added successively to a solution of 3-fluoro-4-hydroxymethyl benzonitrile (1-2, 0.70 g, 4.64 mmol) in methanol (150 mL) to obtain a suspension which was then heated to reflux for 5 hours. It was then cooled down to room temperature and filtered. The filter cake was washed with methanol (10 mL), and the obtained filtrate was concentrated to obtain 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine which was a white crude product (1-3, 0.846 g, 99% yield), which was directly used in the next step. The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 185.0 [M+H] + . NMR: 1 HNMR (400 MHz, CD3OD) δ: 7.51˜7.45 (m, 2H), 7.37˜7.34 (m, 1H), 4.67 (s, 2H).
1.4 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5)
[0066]
[0067] At room temperature, a solution of 4-isobutyl benzoicacid (1-4, 0.819 g, 4.60 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI, 0.882 g, 4.60 mmol) and 1-hydroxybenzotrizole (0.621 g, 4.60 mmol) in N,N-dimethylformamide (10 mL) was stirred for 30 min before the addition of (Z)-3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.846 g, 4.60 mmol). The mixed system was heated in 140° C. oil bath for 2 hours. LCMS indicated that starting materials reacted completely. It was then cooled down to room temperature and most of N,N-dimethylformamide was removed by distillation under reduced pressure. The mixture was extracted with water and ethyl acetate, and the obtained organic phase was washed successively with 0.5N HCl solution, saturated NaHCO 3 solution and water, dried with anhydrous sodium sulfate and filtered, then the filtrate was concentrated to dryness. The residue was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=10/1−4/1) to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was a white solid product (1-5, 0.92 g, 61% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H),
1.5 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6)
[0068]
[0069] At 60° C., a suspension system of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.91 g, 2.79 mmol) and manganese dioxide (2.43 g, 27.9 mmol) in tetrahydrofuran (30 mL) was stirred for 2 hours. Then the suspension system was cooled down to room temperature, filtered and concentrated to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 0.90 g, 99.6% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 325.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
1.6 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 2)
[0070]
[0071] At room temperature, a solution of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 0.90 g, 2.78 mmol), azetidine-3-carboxylic acid (1-7, 0.28 g, 2.78 mmol) and acetic acid (1 mL) in methanol-tetrahydrofuran (20 mL/20 mL) was stirred for 2 hours. Then a solution of sodium cyanoborohydride (1.03 g, 16.35 mmol) in methanol (60 mL) was added to the reaction mixture and the resulting mixture was stirred at room temperature for additional 16 hours and filtered. The filter cake was washed with methanol (10 mL) and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 2) which was a white solid product (0.20 g, 18% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 410.0 [M+H] + . NMR: 1 HNMR (400 MHz, CD3OD) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 3
Synthesis of 1-{2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 3)
1.1 Methyl 4-bromo-2-chlorobenzoate (185312-82-7)
[0072]
[0073] At 0° C., thionyl chloride (3.57 g, 30 mmol) was added dropwise into a solution of 4-bromo-2-chlorobenzoic acid (4.71 g, 20 mmol) in methanol (100 mL) slowly. The ice-salt bath used was removed after that dropping and then the reaction mixture was heated to reflux for 3 hours. TLC and LCMS indicated that starting materials reacted completely. The solvent and excess thionyl chloride were removed by rotary evaporation to give a crude product. Then the crude product was dissolved in dichloromethane (100 mL), washed successively with saturated sodium bicarbonate solution (100 mL×2) and saturated brine (100 mL), dried with anhydrous sodium sulfate and filtered. A yellow solid product (4.79 g, 96% yield) was obtained by rotary evaporation. The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 248.9.8/250.8/252.8 [M+H] + .
1.2 4-bromo-2-chlorobenzyl alcohol (1-1)
[0074]
[0075] At 0° C., lithium aluminum hydride (1.09 g, 30 mmol) was dropped into a solution of methyl 4-bromo-2-chlorobenzoate (4.78 g, 19.16 mmol) in tetrahydrofuran (100 mL) slowly. The ice-salt bath used was removed after that dropping. The reaction was complete (detected with LCMS and TLC) after stirred for 1 hour at room temperature. The mixture was cooled to 0° C. again and the reaction was quenched with water (1.09 mL) and 10% NaOH solution (10.9 mL) respectively. After stirred for 15 min at room temperature, the mixture was filtered and then the filter cake was washed with tetrahydrofuran (50 mL×2) and ethyl acetate EA (50 mL×2). The filtrate was dried with anhydrous sodium sulfate, filtered, and then concentrated to obtain a colorless oil product (3.4 g, 80% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 202.9/204.9 [M−OH] + .
1.3 3-chloro-4-hydroxymethyl benzonitrile (1-2)
[0076]
[0077] Zinc cyanide (0.67 g, 5.73 mmol) and tetrakis(triphenylphosphine) palladium (Pd(PPh 3 ) 4 , 0.33 g, 0.287 mmol) were added into a solution of 4-bromo-2-chlorobenzyl alcohol (1-1, 1.27 g, 5.73 mmol) in DMF (15 mL). After deoxygenated via argon bubbling, the reaction mixture was heated at 100° C. and reacted for 16 hours, cooled down to room temperature, diluted with ethyl acetate (50 mL), washed successively with water (50 mL×3) and saturated brine (50 mL×3), dried with anhydrous sodium sulfate and filtered. The filtrate was concentrated to obtain a crude product. The crude product was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=15/1−4/1) to obtain a white solid product (0.387 g, 40% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 168.0/170.1 [M+H] + .
1.4 (Z)-3-chloro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3)
[0078]
[0079] Hydroxylamine hydrochloride (0.321 g, 4.62 mmol) and sodium bicarbonate (0.776 g, 9.24 mmol) were added successively to a solution of 3-chloro-4-hydroxymethyl benzonitrile (1-2, 0.387 g, 2.31 mmol) in methanol (80 mL) to obtain a suspension which was then heated to reflux for 5 hours. It was then cooled down to room temperature and filtered. The filter cake was washed with methanol (10 mL), and the obtained filtrate was concentrated to obtain, as a white crude product, 3-chloro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.324 g, 70% yield), which was directly used in the next step. The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 201 [M+H] + . NMR: 1 HNMR (400 MHz, DMSO-d6) δ: 9.74 (br, 1H), 7.68 (s, 1H), 7.67 (d, J=8.4 Hz, 1H), 7.54 (d, J=8.4 Hz, 1H), 5.88 (br, 2H), 5.49 (br, 1H), 4.27 (s, 2H).
1.5 2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5)
[0080]
[0081] At room temperature, a solution of 4-isobutyl benzoicacid (1-4, 0.288 g, 1.62 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI, 0.31 g, 1.62 mmol) and 1-hydroxybenzotrizole (0.219 g, 1.62 mmol) in N,N-dimethylformamide (8 mL) was stirred for 30 min before the addition of (Z)-3-chloro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.324 g, 1.21 mmol). The obtained mixed system was heated in 140° C. oil bath for 2 hours. LCMS indicated that starting materials reacted completely. It was then cooled down to room temperature and most of N,N-dimethylformamide was removed by distillation under reduced pressure. The mixture was extracted with water and ethyl acetate, and the organic phase obtained was washed successively with 0.5N HCl solution, saturated NaHCO 3 solution and water, dried with anhydrous sodium sulfate and filtered, then the filtrate was concentrated to dryness. The residue was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=10/1−4/1) to obtain 2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was a white solid product (1-5, 0.36 g, 65% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 343.0/345.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.16 (d, J=1.2 Hz, 1H), 8.10 (d, J=8.4 Hz, 2H), 8.07 (dd, J=1.2 Hz, 8.0 Hz, 1H), 7.66 (d, J=8.0 Hz, 1H), 7.32 (d, J=8.4 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=7.2 Hz, 2H), 0.94 (d, J=7.2 Hz, 6H).
1.6 2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6)
[0082]
[0083] At 40° C., a suspension system of 2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.36 g, 1.05 mmol) and manganese dioxide (0.914 g, 10.5 mmol) in tetrahydrofuran (30 mL) was stirred for 2 hours. Then the suspension system was cooled down to room temperature, filtered and concentrated to obtain a crude product. The crude product was purified by column chromatography (elution system:petroleum ether:ethyl acetate=20/1−10/1) to obtain 2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 0.34 g, 95% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 341.1 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.52 (s, 1H), 8.28 (d, J=1.2 Hz, 1H), 8.16 (dd, J=1.2 Hz, 8.4 Hz, 1H), 8.10 (d, J=8.4 Hz, 2H), 8.04 (d, J=8.4 Hz, 1H), 7.33 (d, J=8.4 Hz, 2H), 2.58 (d, J=7.6 Hz, 2H), 0.94 (d, J=7.6 Hz, 6H).
1.7 1-{2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 3)
[0084]
[0085] At room temperature, a solution of 2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 0.34 g, 1.0 mmol), azetidine-3-carboxylic acid (1-7, 0.101 g, 1.0 mmol) and acetic acid (0.35 mL) in methanol-tetrahydrofuran (10 mL/10 mL) was stirred for 2 hours. Then a solution of sodium cyanoborohydride (0.378 g, 6.0 mmol) in methanol (20 mL) was added to the reaction mixture and the resulting mixture was stirred at room temperature for additional 16 hours and filtered. The filter cake was washed with methanol (10 mL) and then dried to obtain 1-{2-chloro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 3) which was a white solid product (0.109 g, 26% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 426.1/428.3 [M+H] + . NMR: 1 HNMR (400 MHz, CD3OD) δ: 8.33 (d, J=1.6 Hz, 1H), 8.22 (dd, J=1.6 Hz, 8.0 Hz, 1H), 8.16 (d, J=8.0 Hz, 2H), 7.76 (d, J=8.0 Hz, 1H), 7.45 (d, J=8.0 Hz, 2H), 4.72 (s, 2H), 4.46 (m, 4H), 3.74 (m, 1H), 2.63 (d, J=7.2 Hz, 2H), 1.97 (m, 1H), 0.96 (d, J=7.2 Hz, 6H).
Example 4
Synthesis of 1-{2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 4)
1.1 Methyl 2,4-dibromobenzoate (54335-33-0)
[0086]
[0087] At 0° C., thionyl chloride (3.57 g, 30 mmol) was added dropwise into a solution of 2,4-dibromobenzoicacid (5.60 g, 20 mmol) in methanol (100 mL) slowly. The ice-salt bath used was removed after that dropping and then the reaction mixture was heated to reflux for 3 hours. TLC and LCMS indicated that starting materials reacted completely. The solvent and excess thionyl chloride were removed by rotary evaporation to give a crude product. Then the crude product was dissolved in dichloromethane (100 mL), washed successively with saturated sodium bicarbonate solution (100 mL×2) and saturated brine (100 mL), dried with anhydrous sodium sulfate and filtered. A yellow solid product (5.92 g, 100% yield) was obtained by rotary evaporation. The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 292.8/294.7/269.9 [M+H] + .
1.2 2,4-dibromobenzyl alcohol (1-1)
[0088]
[0089] At 0° C., lithium aluminum hydride (1.14 g, 30 mmol) was dropped into a solution of methyl 2,4-dibromobenzoate (5.90 g, 20 mmol) in tetrahydrofuran (120 mL) slowly. The ice-salt bath used was removed after that dropping. The reaction was complete (detected with LCMS and TLC) after stirred for 1 hour at room temperature. The mixture was cooled to 0° C. again and the reaction was quenched with water (1.14 mL) and 10% NaOH solution (11.4 mL) respectively. After stirred for 15 min at room temperature, the mixture was filtered and then the filter cake was washed with tetrahydrofuran (60 mL×2) and ethyl acetate EA (60 mL×2). The filtrate was dried with anhydrous sodium sulfate, filtered, concentrated, and then purified by column chromatography (elution system:petroleum ether:ethyl acetate=10/1−4/1) to obtain a colorless oil product (2.3 g, 43% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 246.9/248.9/250.9 [M−OH] + .
1.3 3-bromo-4-hydroxymethyl benzonitrile (1-2)
[0090]
[0091] Zinc cyanide (1.01 g, 8.65 mmol) and tetrakis(triphenylphosphine) palladium (Pd(PPh 3 ) 4 , 0.50 g, 0.43 mmol) were added into a solution of 2,4-dibromobenzyl alcohol (1-1, 2.3 g, 8.65 mmol) in DMF (20 mL). After deoxygenated via argon bubbling, the reaction mixture was heated at 80° C. and reacted for 5 hours, cooled down to room temperature, diluted with ethyl acetate (80 mL), washed successively with water (80 mL×3) and saturated brine (80 mL×3), dried with anhydrous sodium sulfate and filtered. The filtrate was concentrated to obtain a crude product. The crude product was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=15/1−4/1) to obtain a white solid product (0.81 g, 44% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 211.9/213.9 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 7.82 (s, 1H), 7.69 (d, J=8.0 Hz, 1H), 7.65 (d, J=8.0 Hz, 1H), 4.80 (s, 2H).
1.4 (Z)-3-bromo-N′-hydroxy-4-hydroxymethyl benzamidine (1-3)
[0092]
[0093] Hydroxylamine hydrochloride (0.524 g, 7.54 mmol) and sodium bicarbonate (1.27 g, 15.08 mmol) were added successively to a solution of 3-bromo-4-hydroxymethyl benzonitrile (1-2, 0.80 g, 3.77 mmol) in methanol (120 mL) to obtain a suspension which was then heated to reflux for 5 hours. It was then cooled down to room temperature and filtered. The filter cake was washed with methanol (10 mL), and the filtrate was concentrated to obtain 3-bromo-N′-hydroxy-4-hydroxymethyl benzamidine which was a white crude product (1-3, 0.90 g, 97% yield), which was directly used in the next step. The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 245/247 [M+H] + .
1.5 2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5)
[0094]
[0095] At room temperature, a solution of 4-isobutyl benzoicacid (1-4, 0.653 g, 3.67 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI, 0.704 g, 3.67 mmol) and 1-hydroxybenzotrizole (0.495 g, 3.77 mmol) in N,N-dimethylformamide (10 mL) was stirred for 30 min before the addition of (Z)-3-bromo-N-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.90 g, 3.67 mmol). The mixed system was heated in 140° C. oil bath for 2 hours. LCMS indicated that starting materials reacted completely. It was then cooled down to room temperature and most of N,N-dimethylformamide was removed by distillation under reduced pressure. The mixture was extracted with water and ethyl acetate, and the obtained organic phase was washed successively with 0.5N HCl solution, saturated NaHCO 3 solution and water, dried with anhydrous sodium sulfate and filtered, then the filtrate was concentrated to dryness. The residue was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=10/1−4/1) to obtain 2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was a white solid product (1-5, 0.36 g, 36% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 387.1/389.1 [M+H] + .
1.6 2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6)
[0096]
[0097] At 50° C., a suspension system of 2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.51 g, 1.32 mmol) and manganese dioxide (1.15 g, 13.2 mmol) in tetrahydrofuran (30 mL) was stirred for 2 hours. Then the suspension system was cooled to room temperature, filtered and concentrated to obtain a crude product. The crude product was purified by column chromatography (elution system:petroleum ether:ethyl acetate=20/1−10/1) to obtain 2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 0.34 g, 67% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 385.0/387.0 [M+H] + .
1.7 1-{2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 4)
[0098]
[0099] At room temperature, a solution of 2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 0.34 g, 0.88 mmol), azetidine-3-carboxylic acid (1-7, 0.089 g, 0.88 mmol) and acetic acid (0.3 mL) in methanol-tetrahydrofuran (10 mL/10 mL) was stirred for 2 hours. Then a solution of sodium cyanoborohydride (0.333 g, 5.28 mmol) in methanol (20 mL) was added to the reaction mixture and the resulting mixture was stirred at room temperature for additional 16 hours and filtered. The filter cake was washed with methanol (10 mL) and then dried to obtain 1-{2-bromo-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 4) which was a white solid product (0.1112 g, 27% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 469.9/471.8 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.39 (d, J=1.2 Hz, 1H), 8.12 (dd, J=1.2 Hz, 8.4 Hz, 1H), 8.08 (d, J=8.4 Hz, 2H), 7.70 (d, J=8.4 Hz, 1H), 7.31 (d, J=8.4 Hz, 2H), 4.23 (s, 2H), 4.08 (m, 2H), 3.99 (m, 2H), 3.44 (m, 1H), 2.56 (d, J=6.8 Hz, 2H), 1.91 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
Example 5
Synthesis of 1-{2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 5)
1.1 4-bromo-2-methylbenzyl alcohol (1-1)
[0100]
[0101] At 0° C., lithium aluminum hydride (1.425 g, 37.5 mmol) was dropped into a solution of methyl 4-bromo-2-methylbenzoate (5.725 g, 25 mmol) in tetrahydrofuran (120 mL) slowly. The ice-salt bath used was removed after that dropping. The reaction was complete (detected by LCMS and TLC) after stirred for 1 hour at room temperature. The mixture was cooled to 0° C. again and the reaction was quenched with water (1.43 mL) and 10% NaOH solution (14.3 mL) respectively. After stirred for 15 min at room temperature, the mixture was filtered and then the filter cake was washed with tetrahydrofuran (80 mL×2) and ethyl acetate EA (80 mL×2). The filtrate was dried with anhydrous sodium sulfate, filtered, and then concentrated to obtain a colorless oil product (4.535 g, 90% yield).
1.2 3-methyl-4-hydroxymethyl benzonitrile (1-2)
[0102]
[0103] Zinc cyanide (2.63 g, 22.5 mmol) and tetrakis(triphenylphosphine) palladium (Pd(PPh 3 ) 4 , 1.31 g, 1.13 mmol) were added into a solution of 4-bromo-2-methylbenzyl alcohol (1-1, 4.53 g, 22.5 mmol) in DMF (50 mL). After deoxygenated via argon bubbling, the reaction mixture was heated at 100° C. and reacted for 16 hours, cooled down to room temperature, diluted with ethyl acetate (120 mL), washed successively with water (120 mL×3) and saturated brine (120 mL×3), dried with anhydrous sodium sulfate and filtered. The filtrate was concentrated to obtain a crude product. The crude product was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=15/1−4/1) to obtain a white solid product (2.8 g, 84% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 148.1 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 7.57 (d, J=7.6 Hz, 1H), 7.52 (d, 7.6 Hz, 1H), 7.44 (s, 1H), 4.76 (d, J=5.6 Hz, 2H), 2.34 (s, 3H).
1.3 (Z)-3-methly-N′-hydroxy-4-hydroxymethyl benzamidine (1-3)
[0104]
[0105] Hydroxylamine hydrochloride (2.64 g, 38 mmol) and sodium bicarbonate (6.38 g, 76 mmol) were added successively to a solution of 3-methyl-4-hydroxymethyl benzonitrile (1-2, 2.8 g, 19 mmol) in methanol (500 mL) to obtain a suspension which was then heated to reflux for 5 hours. It was then cooled to room temperature and filtered. The filter cake was washed with methanol (100 mL×2), and the obtained filtrate was concentrated to obtain 3-methyl-N′-hydroxy-4-hydroxymethyl benzamidine which was a white crude product (1-3, 3.425 g crude product, 100% yield), which was directly used in the next step. The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 181.0 [M+H] + .
1.4 2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5)
[0106]
[0107] At room temperature, a solution of 4-isobutyl benzoicacid (1-4, 3.382 g, 19 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI, 3.642 g, 19 mmol) and 1-hydroxybenzotrizole (2.565 g, 19 mmol) in N,N-dimethylformamide (60 mL) was stirred for 30 min before the addition of (Z)-3-methyl-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 3.42 g, 19 mmol). The mixed system was heated in 140° C. oil bath for 2 hours. LCMS indicated that starting materials reacted completely. It was then cooled to room temperature and most of N,N-dimethylformamide was removed by distillation under reduced pressure. The mixture was extracted with water and ethyl acetate, and the organic phase obtained was washed successively with 0.5N HCl solution, saturated NaHCO 3 solution and water, dried with anhydrous sodium sulfate and filtered, then the filtrate was concentrated to dryness. The residue was then purified by column chromatography (elution system:petroleum ether:ethyl acetate=10/1−4/1) to obtain 2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was a white solid product (1-5, 2.51 g, 41% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 323.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.12 (d, J=8.4 Hz, 2H), 7.98 (m, 2H), 7.59 (d, J=8.0 Hz, 1H), 7.32 (d, J=8.4 Hz, 2H), 4.77 (s, 2H), 2.57 (d, J=7.2 Hz, 2H), 2.42 (s, 3H), 1.93 (m, 1H), 0.92 (d, J=7.2 Hz, 6H).
1.5 2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6)
[0108]
[0109] At 60° C., a suspension system of 2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 2.5 g, 7.76 mmol) and manganese dioxide (6.75 g, 77.6 mmol) in tetrahydrofuran (100 mL) was stirred for 2 hours. Then the suspension system was cooled to room temperature, filtered and concentrated to obtain 2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 2.4 g, 97% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 321.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.38 (s, 1H), 8.20˜8.13 (m, 4H), 7.97 (d, J=8.4 Hz, 1H), 7.37 (d, J=8.0 Hz, 2H), 2.80 (s, 3H), 2.61 (d, J=7.6 Hz, 2H), 1.96 (m, 1H), 0.96 (d, J=7.6 Hz, 6H).
1.6 1-{2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 5)
[0110]
[0111] At room temperature, a solution of 2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 0.88 g, 2.75 mmol), azetidine-3-carboxylic acid (1-7, 0.278 g, 2.75 mmol) and acetic acid (1 mL) in methanol-tetrahydrofuran (20 mL/20 mL) was stirred for 2 hours. Then a solution of sodium cyanoborohydride (1.04 g, 16.5 mmol) in methanol (60 mL) was added to the reaction mixture and the resulting mixture was stirred at room temperature for additional 16 hours and filtered. The filter cake was washed with methanol (10 mL×2) and then dried to obtain 1-{2-methyl-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (0.23 g, 21% yield). The molecular ion peak shown by liquid chromatography-mass spectrometry was: MS (ESI): m/z 406.0 [M+H] + . NMR: 1 HNMR (400 MHz, CD3OD) δ: 8.12 (d, J=8.0 Hz, 2H), 8.08 (s, 1H), 8.04 (d, J=7.6 Hz, 1H), 7.53 (d, J=7.6 Hz, 1H), 7.42 (d, J=8.0 Hz, 2H), 4.47 (s, 2H), 4.23 (m, 4H), 3.44 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 2.52 (s, 3H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 6
In Vivo Pharmacokinetic Experiment of Compounds Provided by Present Invention
[0112] In this Example, the pharmacokinetic properties of compounds 1, 2, 3, 4 and 5 were evaluated via. i.v. and p.o. dosing to Sprague Dawley rats.
[0113] Experimental animals used in this Example and hereinafter were male SD rats of 7-9 weeks old, with body weight ranging from 186 to 231 g, which were purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd. The animals were quarantined by veterinarian for 5 days after purchase, then animals had passed quarantine inspection were selected to be tested under SPE conditions, wherein the tested animals are assigned into 3 rats per group as follows.
[0114] Oral administration group: 2.74 mg of each of compounds 1-5 was respectively prepared into a solution of 0.3 mg/mL by using 9.113 mL 0.5% CMC-Na as a diluent. Each solution was vortexed 1-2 mins after mixed fully, and then was ultrasonically treated for 20-30 mins until a uniform suspension was obtained. The uniform suspension was used as medicine administrated to oral administration group, and the administration was conducted with a dose of 10 mL/kg body weight of each rat.
[0115] Intravenous administration group: 1.61 mg of each of compounds 1-5 was respectively prepared into a solution of 1 mg/mL by using 1.610 mL 10% HP-β-CD as a diluent. Each solution was vortexed 1-2 mins after mixed fully, and then was ultrasonically treated for 28-30 mins. The obtained solution was used as medicine administrated to intravenous administration group, and the administration was conducted with a dose of 1 mL/kg body weight of each rat.
[0116] For both oral administration group and intravenous administration group, blood samples were collected at 0.0833 h (5 min), 0.25 h (15 min), 0.5 h, 1 h, 2 h, 4 h, 8 h, and 24 h after administration. After isoflurane anesthesia 0.3 mL whole blood was collected from orbital venous plexus of the animals at each time point. The animals would be euthanized after all samples were collected.
[0117] The collected blood samples were placed in EP tubes containing heparin sodium (about 10 μl, 1000 IU/mL), which were then placed in trash ice immediately, and centrifuged at 4,000 rpm and a low temperature (4° C.) for 5 minutes. The plasma was isolated rapidly and then stored at −20° C. until analysis.
[0118] The concentration of each compound in blood was measured by LC-MS/MS-001 (Q-trap-3200) with osalmide as internal standard material, as follows. 24 μL blank plasma was added into 6 μL plasma sample (5 times of dilution), and then a solution of acetonitrile containing 150 μL internal standard material (osalmide in 100 μg/mL) was added in. The mixture was shaken for 5 minutes, and then centrifuged at 4,000 rpm for 5 minutes. 2 μL of the obtained sample was implanted into LC-MS/MS for analysis. As for undiluted plasma sample, 30 μL of it was added into a solution of acetonitrile containing 150 μL internal standard material (osalmide in 100 μg/mL). The mixture was shaken for 5 minutes, and then centrifuged at 4,000 rpm for 5 minutes. 2 μL of the obtained sample was implanted into LC-MS/MS for analysis.
[0119] As for data analysis, WinNolin (V6.2) non-compartment model (NCA) was used for calculating main metabolic pharmacokinetic parameters including t1/2, AUC(0−t), AUCinf, V, Cl, MRT, etc., and Microsoft Office EXCEL was used for calculating mean values, standard deviations and coefficients of variation.
[0120] It is clearly indicated from the data shown in Table 1 that, compared with the terminal half-life of compound 1 which was about 11 hours, the terminal half-life of each of compounds 2, 3 and 4 were less than 5.5 hours after oral administration. Therefore, the half-lives of the three compounds with halogen substituents (compounds 2, 3 and 4) were almost 50% shorten than that of compound 1.
[0121] There is a similar half-life change in the study on pharmacokinetics of intravenous administration. It is clearly indicated from the data shown in Table 2 that, compared with the terminal half-life and mean residence time (MRT) of compound 1, the terminal half-life and mean residence time of each of compounds 2, 3 and 4 substituted with halogen were reduced significantly. These data show that halogen substitutions at position 2 in compound 1 can accelerate the elimination of the compounds from the blood. What's more, the results of study on clearance (Cl) showed that, the shortening of the terminal half-life and mean residence time was not caused by the increased clearance of the compounds.
[0122] The significant shorter in vivo half-lives of compounds 2, 3 and 4 cannot be expected with conventional theory, as no similar results are obtained by substituting with other substituents at the same position of compound 1. For example, the half-life was extended rather than shortened (see Tables 1 and 2) when the substituent is methyl (corresponding to compound 5). Moreover, it can be seen from the curve of compound concentration in blood vs. time after oral administration that, compared with compounds 1 and 5, the elimination speed of compounds 2, 3 and 4 was accelerated obviously when they got to the highest concentration ( FIGS. 1A and 1B ).
[0000]
TABLE 1
pharmacokinetics of oral administration (3 mg/kg)
T max
C max
AUC inf
T½
F
Compound
(hr)
(ng/mL)
(hr * ng/mL)
(hr)
(%)
Compound 1
2.00
365 ± 51.5
6197 ± 147
10.6 ± 1.07
82.5
Compound 2
2.00
341 ± 36.2
3829 ± 184
5.47 ± 0.63
63.4
Compound 3
3.33
681 ± 61.1
8107 ± 469
5.30 ± 0.51
96.1
Compound 4
1.15
346 ± 29.6
4419 ± 449
5.37 ± 0.15
52.9
Compound 5
3.33
249 ± 8.74
5460 ± 401
12.3 ± 2.09
74.0
[0000]
TABLE 2
pharmacokinetics of intravenous administration (1 mg/kg)
CL
Vss
AUC inf
T½
MRT inf
Compound
(L/hr/kg)
(L/kg)
(hr * ng/mL)
(hr)
(hr)
Compound 1
0.427 ± 0.063
4.65 ± 0.389
2376 ± 329
8.69 ± 0.80
11.0 ± 1.20
Compound 2
0.499 ± 0.039
3.12 ± 0.101
2012 ± 146
5.47 ± 0.42
6.28 ± 0.44
Compound 3
0.366 ± 0.050
2.65 ± 0.229
2767 ± 410
5.04 ± 0.37
5.11 ± 0.39
Compound 4
0.362 ± 0.026
2.75 ± 0.112
2768 ± 200
5.29 ± 0.60
5.23 ± 0.36
Compound 5
0.454 ± 0.018
5.87 ± 0.802
2203 ± 89.5
10.1 ± 1.02
12.9 ± 1.24
Example 7
Effect of Compounds Provided by the Present Invention on the Internalization of S1P1 and S1P3
1) Internalization Effect Experiment on S1P1
[0123] It is well known that S1P1 small molecule agonists can prevent lymphocytes from entering the peripheral circulation by inducing internalization of S1P1 on cell surface. In order to determine whether the compounds provided by present invention have an activity of inducing S1P1 internalization, CHO—S cells expressing human S1P1, to replace the lymphocytes, are used as detection system of S1P1 internalization. For ease of monitoring the S1P1 on cell surface, a Myc tag is fused to N-terminal of S1P1, thus the expression of S1P1 is analyzed by flow cytometry after incubating the cells with fluorescent-labeled antibody against the Myc tag.
[0124] A 10 mM stock solution was prepared by dissolving compound 2 provided by the present invention in dimethyl sulfoxide (DMSO), and then the stock solution was diluted to different concentrations as desired with DMEM. CHO—S cells bearing human S1P1 with Myc tag were harvested and then adjusted to a density of one million cells per mL by Dulbecco's modified Eagle's medium (DMEM). Different concentrations of Compound 2 diluted in an equal volume were mixed and the cell suspension and then incubated at 37° C. for 1 hour. After incubation, the mixture was centrifuged at 800 RPM for 5 minutes to obtain the cells. The cells were resuspended in FACS buffer (PBS containing 1% BSA), and Myc antibody labelled with fluorescein isothiocyanate (FITC) (from Californian Miltenyi Biotec GmbH, USA) was added in and incubated for 1 hour on ice. The cells were washed, resuspended in pre-cooled FACS buffer and analysed by FACS Calibur flow cytometry.
[0125] The experiment data showed that compound 2 exhibited an activity of inducing S1P1 internalization in a dose-dependent manner (Table 3). Activities of compounds 3 and 4 to induce S1P1 internalization were also detected by the same method, and the results obtained show no significant difference with that of compound 1. This indicates that all the compounds obtained through substitution with F, Cl and Br (compounds 2, 3 and 4) still possess the activity of activating S1P1 while having obviously shortened half-lives.
2) Internalization Effect Experiment of S1P3
[0126] CHO—S cells expressing human S1P3 were used to perform internalization detection test. Besides cells, experimental method was the same with the method of the internalized detection experiment of S1P1.
[0127] The experiment results showed that, similar to that of compound 1, effects of compounds 2, 3 and 4 on S1P were specific, namely that the compounds only had internalization activation effect on S1P1 and had no internalization activation effect on S1P3 subtype (Table 3). This indicates that, although compounds with F, Cl or Br substituent obviously have a shortened in vivo half-live as compared with compound 1, the selectivity of the compounds to target S1P1 does not changed. In this regard, the compounds of the present invention are different from FTY720 currently used in the clinic, which is a non-selective S1P agonist. FTY720 may activate several S1P receptors, such as S1P1, S1P2, S1P3, S1P4 and S1P5, thereby resulting in a series of severe side effects, for example, bradycardia.
[0000]
TABLE 3
Activity and selectivity of compounds 2, 3 and 4 to receptors
Receptor
Internalization
(EC50)
S1P1
S1P3
Compound 1
5.69 nM
>1000 nM
Compound 2
9.83 nM
>1000 nM
Compound 3
3.21 nM
>1000 nM
Compound 4
4.20 nM
>1000 nM
Example 8
Effect of Compounds Provided by Present Invention on the Number of Lymphocytes in the Peripheral Blood
[0128] S1P1, which is expressed on the surface of lymphocytes, is essential for lymphocytes to leave the secondary lymphoid tissue and then enter into the peripheral circulation. Small molecule agonists of S1P1 can activate the receptor and result in an internalization effect on the receptor. This mechanism is a currently known mechanism by which lymphocytes are prevented from leaving the secondary lymphoid tissue, then resulting in an decreased number of lymphocytes in the peripheral circulation. In order to determine whether the compounds provided by present invention can reduce the number of lymphocytes in the peripheral blood, an in vivo effect experiment on lymphocytes is performed.
[0129] An appropriate amount of compound 2 was prepared as a suspension with sodium carboxymethylcellulose (CMC-Na) and was given orally to three Sprague-Dawley (SD) rats. Blood samples (0.5 ml) were collected at 30 min before the administration and at different time points after the administration (the collected blood samples were placed in EP tubes containing an appropriate amount of EDTA-2K solution), and analyzed on ADVIA2120 blood cell analyzer directly.
[0130] The experiment results showed that compound 2 reduced the number of lymphocytes in the peripheral blood effectively. The number of lymphocytes in the peripheral blood was reduced obviously at 30 minutes after the administration, and further reduced at all sampling time points (30, 120, 240, 360 and 480 minutes). Compound 2, in all the three doses evaluated, had the activity, wherein more than 50% reduction of lymphocytes in the peripheral blood were observed only with a dose of 0.01 mg/kg, and the most reduction were observed with a dose of 1 mg/kg ( FIG. 2 ). What's more, the effect of compound 2 is specific to lymphocytes, and compound 2 changed the number of peripheral mononuclear cells and other leukocytes unobviously.
[0131] It was found that effect of compounds 3, 4 and 5 on lymphocytes was similar to that of compound 2 by testing compounds 3, 4 and 5 of the present invention with the same method ( FIG. 3 and FIG. 4 ).
Example 9
Effect of Compound 2 on the Development of Collagen Type II-Induced Arthritis in Lewis Rats
[0132] Rheumatoid arthritis in human is an autoimmune disease, in which the patient' own immune system attacks joint tissues. Lymphocytes including T and B cells play an important part in the pathogenesis of the disease. It is known that inhibition of T cell functions by blocking the activation of T cells is an effective treatment of rheumatoid arthritis. Since Compound 2 blocks egress of lymphocytes, it was of interest to determine if it would be efficacious in inhibiting the development of arthritis in the rat CIA mode. To perform the testing, Lewis rats were induced to develop the disease as follows. Rats were anesthetized with isoflurane and were injected intradermally with a total of 0.5 mL CII/CFA emulsion. The emulsion was injected at 3 sites, one site at the base of the tail (0.1 mL), and the other two sites (0.2 mL/site) on the back of the rat near to the base of the tail. An identical booster injection was given i.d. at 7 days after the primary immunization avoiding previous injection sites.
[0133] Compound 2 was prepared as a suspension in 0.5% CMC-Na and was given orally to the rats at the time of CII/CFA injection. The positive control group was given TOFACITINIB orally on day 12 after sensitization. The severity of arthritis in four paws was scored 2 times per week starting on day 7 after sensitization. The criteria was as follows: score 0: No evidence of erythema and swelling; score 1: Erythema and mild swelling confined to the mid-foot (tarsals) or ankle joint; score 2: Erythema and mild swelling extending from the ankle to the mid-foot; score 3: Erythema and moderate swelling extending from the ankle to the metatarsal joints; score 4: Erythema and severe swelling encompass the ankle, foot, and digits. Joint swelling, measured by the volume of hind paws using Plethysmometer, was determined on Day 0, and then 2 times per week from Day 7 to Day 28. Destruction of the joint was determined by X-Ray examination on Day 28. The results showed that at 1 mg/kg, Compound 2 was effective in inhibiting the development of arthritis based on joint swelling ( FIG. 5 ) and destruction of joint structure ( FIG. 6 ). It can be seen from FIG. 5 that Compound 2 had a similar function with TOFACITINIB, but the dosage of it was decreased significantly.
Example 10
Effect of Compound 2 on the Development of Experimental Autoimmune Encephalitis (EAE)
[0134] S1P1 agonists have been shown to be effective in human multiple sclerosis and in animal model of MS. Compound 2 was evaluated for its efficacy for experimental autoimmune encephalomyelitis (EAE), a mouse model of human multiple sclerosis. Eighty female C57BL/6 mice were randomly assigned into eight groups based on body weight and immunized in this study. Each group consisted of ten (10) mice. To induce the disease, MOG 35-55 (MOG, myelin oligo-dendrocyte glycoprotein) was dissolved in saline to a concentration of 2 mg/mL, and was emulsified in modified complete Freund's Adjuvant (CFA). Mice were anesthetized with isoflurane and were then injected with 100 μL of emulsion subcutaneously into the shaved backs of the mice at three sites, one along the midline of the back between the shoulders, and two on each side of the midline on the lower back. Pertuxus toxin (200 ng in 200 μL of PBS) was administered i.p. on the day of immunization and 48 hours after for all groups. EAE development was assessed by clinically scoring of the mice once daily from Day 0 to Day 30 post immunization.
[0135] Compound 2 prepared as a Na CMC suspension, was administered orally starting at the time of MOG immunization and continued for the entire duration of the study. The data showed that at all three dosages evaluated (0.03, 0.1 and 1 mg/kg), Compound 2 effectively inhibited development of EAE ( FIG. 7 ).
Example 11
Effect of Compound 2 on the Cardiovascular Function of Beagle Dogs
[0136] FTY720 is a non-selective S1P1 agonist that has been shown to have various cardiovascular effects including bradycardia in humans. To determine whether Compound 2 has an effect on heart rate and QT interval, the compound was evaluated in a telemetry assay in conscious beagle dog.
[0137] An appropriate amount of CMC-Na was prepared as a 0.5% CMC-Na (w/v) solution with sterilized water for injection. The solution was prepared one day before administration.
[0138] Solutions of Compound 2 (samples) with the concentration of 2, 6 and 20 mg/mL were prepared one day before administration as follows. An appropriate amount of Compound 2 was added into an appropriate amount of 0.5% CMC-Na solution. The obtained mixture was emulsified and homogenized on an emulsification isotropic machine. Theoretical concentrations of Compound 2 in the prepared sample solutions were 2, 6 and 20 mg/mL.
[0139] A total of 8 animals and a Double Latin squared experimental design were used in this experiment. Administration cycles were separated by 3-5 days. One day before each administration cycle, the animals were weighted and fasted overnight. On the day of administration, telemetry system (Implantable physiological signal telemetry system 1, Data Science International Inc., USA) was turned on, test parameters were set, implants were activated and physiological indexes of the animals were recorded. About two hours later after the turning on of the system, the animals were administered according to the cycles designed. Index data of blood pressure, electrocardiogram, body temperature and the like of the animals were collected within 24 hours after the administration. During the collection, the system was turned off properly and then turned on again in order to avoid possible data overflow. The switching process did not affect the value of the setting data points and times switching the system were recorded. On the next day when the recording was completed, the telemetry system was turned off. Time points of detection are: 1 hour before administration (−1 h), and 0.5 h (±5 min), 1 h (±10 min), 1.5 h (±10 min), 2 h (±15 min), 3 h (±15 min), 4 h (±15 min), 8 h (±45 min), 24 h (±1 h) after administration. All data was collected by PONEMAH Version 4.8 software automatically. Parameters would be analyzed using artificial set after the collection was completed. The data was, firstly, analyzed by PONEMAH Version 4.8 software automatically, and then checked point by point artificially for selected values. As for indexes of heart rate, blood pressure, respiration and body temperature, mean values of continuous waveform within 1 min were selected, and mean values of continuous waveform within 10 seconds were selected for other electro-cardio indexes. During the value selection, immediate data at the detection time points was preferred. However, if there were problems such as large noise disturbance, abnormalities in heart rate, or no clearly waveform could be identified at the detection time points, waveform with clear signal in the given range was selected. Furthermore, if there still no clear waveform at the given range was available for analysis, data which is available for analysis should be found around the value points, which should be explained specially in a value point table. Time at which values were selected were recorded.
[0140] Statistical software SPSS13.0 was used to process data in this experiment. Two-tailed analyses were performed whereby the level of significance was set at p<0.05. Indexes of blood pressure, electrocardiogram, respiration and body temperature were expressed as “mean±standard error”, and then analyzed according to following procedure: firstly, homogeneity test was performed on the data by use of Levene Test, and if the data was uniform (P≦0.05), single-factor variance analysis was performed; and if the result of variance analysis was significant (P≦0.05), Dunnett's multiple comparison was performed on difference between vehicle group and sample group. If the result of Levene Test was significant (P≦0.05), Kruskal-wallis non-parametric test was performed; and if the result of Kruskal-wallis non-parametric test was significant (P≦0.05), pairwise comparison was performed by use of Mann-Whitney U test.
[0141] The change range was calculated after the data collected at time points with significant difference or significant change trend are normalized. The formulae of normalization was Δ %=[(b1−b0)−(a1−a0)]/a1×100, wherein b1 represented value of time point after administrating the samples, b0 represented value of time point before administrating the samples, a1 represented corresponding value of time point after administrating the vehicle, a0 represented value of time point before administrating the vehicle, and Δ % represented the change range.
[0142] Comparing heart rate, QT interval and QTcF interval of animals administrated with doses of sample to indexes of electrocardiogram of animals administrated with vehicle, no significant difference (P>0.05) or change trend was found ( FIG. 8A to FIG. 8 C).
[0143] As for synthesis method of 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid (Compound 2), Examples of optimizing the method and the condition thereof are provided below.
[0144] The synthesis of compound 2 will be carried out according to the method including the following steps:
[0000]
Example 12
Screening for Step (1) in Synthesis Method of the Present Invention
[0145] Crude product of compound represented by formula 1-5 was prepared and characterized according to Example 2. The purity detected by LCMS was 77.25%. A screening for crystallization purification condition was conducted on the prepared crude product. Crystallization operation was as follows: the crude product was dissolved in a crystallization solvent, crystallized at 20° C., and dried by vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol represented by formula 1-5 which is an almost white solid product. The purity was detected by LCMS.
[0146] Firstly, the above crystallization operation was performed according to contents listed in Table 4 for screening the preferred crystallization solvent.
[0000]
TABLE 4
Screening of solvents and the amount thereof for
crystallization purification
Purity
Amount of the
Purity of
of
solvent (crude
crude
pure
Yield of
Solvent
product:solvent)
product
product
purification
Ethyl acetate
1 g:1 ml
77.25%
96.72%
A little of
precipitates
Acetone
1 g:1 ml
77.25%
95.22%
A little of
precipitates
Methanol
1 g:3 ml
77.25%
99.08%
55.4%
Ethanol
1 g:3 ml
77.25%
99.36%
37.4%
Tetrahydrofuran
1 g:1 ml
77.25%
Clear
solution
Dichloromethane
1 g:1 ml
77.25%
98.58%
A little of
precipitates
Water
1 g:1 ml
77.25%
95.34%
84%
[0147] It can be seen from Table 4 that, when single solvent was used for crystallization, the purity of the product was increased obviously by using methanol or ethanol as solvent. The yield was much higher when using methanol than using ethanol, but it was only 55.4%. The purity of the product was not increased substantially by using water as solvent, but the yield loss was minor. Therefore, it had been tried in the follow-up study to use a mixed solvent of methanol and water as crystallization solvent.
[0148] Secondly, the above crystallization operation was performed according to contents listed in Table 5 for screening the preferred ratio of methanol and water in the mixed solvent. The ratio of the crude product (in g, by weight) to the mixed solvent (in ml, by volume) for crystallization is 1:5.
[0000]
TABLE 5
Screening of the ratio of methanol and water in the mixed solvent
Purity
Solvent ratio
of crude
Purity of pure
Yield of
Solvent
(volume ratio)
product
product
purification
Methanol
1:1
77.25%
98.32%
75.2%
and water
Methanol
2:1
77.25%
99.13%
73.1%
and water
Methanol
3:1
77.25%
99.27%
72.7%
and water
Methanol
1:2
77.25%
97.20%
79.8%
and water
Methanol
1:3
77.25%
95.68%
83.2%
and water
[0149] It can be seen from Table 5 that the purity of the product was increased, but the yield was decreased by increasing the amount of methanol in the mixed solvent; and the yield of purification was increased, but the purity of the product was decreased by increasing the amount of water. Overally considered, a volume ratio of 3:1 was selected as the ratio of methanol and water in the mixed solvent.
[0150] Thirdly, the above crystallization operation was performed according to contents listed in Table 6 for screening the preferred amount of the mixed solvent. The volume ratio of methanol and water in the mixed solvent is 3:1.
[0000]
TABLE 6
Screening of the amount of the solvent
Amount of solvent
Purity
Purity
(crude product:
of crude
of pure
Yield of
Solvent
solvent)
product
product
purification
Methanol and
1 g:3 ml
77.25%
98.99%
69.9%
water
Methanol and
1 g:5 ml
77.25%
99.16%
72.2%
water
Methanol and
1 g:10 ml
77.25%
99.05%
68.9%
water
Methanol and
1 g:20 ml
77.25%
99.30%
67.2%
water
[0151] It can be seen from Table 6 that a high yield and purity were obtained when the ratio of weight of the crude product to volume of the solvent was 1 g:5 mL. However, although a higher purity was obtained when the ratio of weight of the crude product to volume of the solvent is 1 g:20 mL than the ratio is 1 g:5 mL, yield was less. Therefore, a ratio of 1 g:5 mL was selected as the ratio of weight of the crude product to volume of the solvent used as the solvent system for crystallization.
Example 13
Screening for Step (2) in Synthesis Method of the Present Invention
[0152] Step (2) of the present invention was conducted according to the following procedure: 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol represented by formula 1-5 purified from Example 1 was dissolved in reaction solvent, and then active manganese dioxide was added in. The reaction liquid was heated to reflux and continued to react. The reaction was cooled down to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde represented by formula 1-6 which was a white solid product. The conversion rate was detected by LCMS.
[0153] Firstly, the synthesis step above was carried out according to contents listed in Table 7 for screening the preferred reaction solvent. The mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol represented by formula 1-5 to manganese dioxide was 1:6. Expression “raw material” in Tables 7-9 refers to 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol represented by formula 1-5.
[0000]
TABLE 7
Screening of the reaction solvent
Amount of
solvent (raw
Reaction
Conversion
Solvent
material:solvent)
time
rate (LCMS)
Yield
Tetrahydrofuran
1 g:10 ml
1 h
96.26%
92.2%
Ethyl acetate
1 g:10 ml
1 h
93.3%
93.3%
Toluene
1 g:10 ml
1 h
91.7%
91.7%
[0154] It can be seen from Table 7 that there was a little effect on the conversion rate and the yield when tetrahydrofuran, ethyl acetate or toluene was used as the reaction solvent. However, a safety risk existed when tetrahydrofuran was used as the reaction solvent and a high toxicity when toluene was used as the reaction solvent, thus, ethyl acetate was selected as the reaction solvent.
[0155] Secondly, the synthesis step above was carried out according to contents listed in Table 8 for screening the preferred amount of the solvent. Ethyl acetate was used as the reaction solvent, and the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol represented by formula 1-5 to manganese dioxide is 1:6.
[0000]
TABLE 8
Screening of the amount of the reaction solvent
Amount of the solvent
Conversion rate
(raw material:solvent)
Reaction time
(LCMS)
Yield
1 g:10 ml
1 h
97.76%
93.3%
1 g:20 ml
1 h
98.93%
92.6%
1 g:30 ml
1 h
98.83%
93.1%
[0156] It can be seen from Table 8 that there was a little effect on the conversion rate and the yield when the ratio of weight of the raw material to the volume of the solvent was 1 g:10 ml, 1 g:20 ml and 1 g:30 ml. Considering cost, the ratio of 1 g:10 ml was selected as the amount of the reaction solvent.
[0157] Thirdly, the synthesis step above was carried out according to contents listed in Table 9 for screening the preferred amount of manganese dioxide. An amount of 1 g:10 ml of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol represented by formula 1-5 to ethyl acetate was used.
[0000]
TABLE 9
Screening of the amount of oxidant
Amount of oxidant
(the mole ratio of raw material to
Reaction
Conversion rate
manganese dioxide)
time
(LCMS)
Yield
1:4
3 h
96.91%
86.6%
1:5
3 h
97.06%
91.0%
1:6
3 h
97.03%
93.3%
1:10
3 h
97.12%
93.6%
[0158] It can be seen from Table 9 that a high conversion rate and yield were obtained when the mole ratio of raw material to manganese dioxide was 1:6. However, there was a little effect on conversion rate and yield when the mole ratio of raw material to manganese dioxide was increased to 1:10. Therefore, considering both cost and yield, a mole ratio of 1:6 was selected as the amount of raw material and manganese dioxide.
Example 14
Screening for Step (3) in Synthesis Methods of the Present Invention
[0159] The step (3) of the present invention was conducted according to the following procedure:
[0160] At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde of formula 1-6, azetidine-3-carboxylic acid of formula 1-7 and glacial acetic acid were added into the reaction solvent and stirred for 2 hours at 20° C. NaBH3CN was dissolved in methanol, and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The reaction liquid was stirred to react at 20° C. after dropping and filtered. The filter cake was washed with methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid represented by formula IB (compound 2) which was a white solid product. The conversion rate was detected by LCMS.
[0161] Firstly, the synthesis step above was carried out according to contents listed in Table 10 for screening the preferred reaction solvent. The mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde of formula 1-6 to azetidine-3-carboxylic acid of formula 1-7 was 1:1.05; the mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde of formula 1-6 to sodium cyanoborohydride is 1:1; the dropping temperature of the solution of NaBH3CN in methanol was 15-20° C.; and expression “raw material” in Tables 10-12 referred to 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde represented by formula 1-6.
[0000]
TABLE 10
Screening of the reaction solvent
Amount of
Conversion
solvent (raw
Reaction
rate
Solvent
material:solvent)
time
(LCMS)
Yield
Tetrahydrofuran
1 g:40 ml
6 h
1.64%
Methanol
1 g:40 ml
6 h
79.26%
69.10%
Ethanol
1 g:40 ml
6 h
66.20%
53.23%
[0162] It can be seen from Table 10 that the conversion rate was very low when tetrahydrofuran was used as the reaction solvent. Whereas both the conversion rate and the yield were higher when methanol or ethanol was used as the reaction solvent.
[0163] Secondly, the synthesis step above was carried out according to contents listed in Table 11 for screening the preferred amount of reducing agent. The mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde of formula 1-6 to azetidine-3-carboxylic acid of formula 1-7 was 1:1.05; the reaction solvent was methanol and the dropping temperature of the solution of NaBH3CN in methanol was 15-20° C.
[0000]
TABLE 11
Screening of the amount of reducing agent
Amount of reducing
agent (the mole ratio of
raw material to sodium
Reaction
Conversion
cyanoborohydride)
time
rate (LCMS)
Yield
Purity
1:0.5
15 h
66.42%
67.20%
94.58%
1:1
15 h
79.26%
69.10%
95.50%
1:2
15 h
73.77%
65.61%
94.24%
1:6
15 h
64.51%
53.27%
94.36%
[0164] It can be seen from Table 11 that the conversion rate, the yield and the purity of the product were all higher when the mole ratio of raw material to sodium cyanoborohydride was 1:1.
[0165] Thirdly, the synthesis step above was carried out according to contents listed in Table 12 for screening the preferred dropping temperature of the reducing agent. The mole ratio of 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde of formula 1-6 to azetidine-3-carboxylic acid of formula 1-7 was 1:1.05; and the reaction solvent was methanol.
[0000]
TABLE 12
Screening of dropping temperature of the reducing agent
Amount
of
reducing
agent
(raw
material
(1-6):
Amount of
Con-
Tempera-
reducing
solvent (raw
Dropping
version
ture
agent)
material:solvent)
time
rate
Purity
0-5° C.
1 Eq.
40 V
20 min
67.65%
95.61%
5-15° C.
1 Eq.
40 V
20 min
71.04%
96.91%
15-20° C.
1 Eq.
40 V
20 min
74.50%
97.91%
[0166] It can be seen from Table 12 that both the conversion rate and the purity of the product were higher when the dropping temperature of sodium cyanoborohydride was 15-20° C.
Example 15
Synthesis Method of the Present Invention
[0167] (1) At room temperature, 4-isobutyl benzoicacid (1-4, 0.148 Kg, 0.83 mol) was dissolved in N,N-dimethylformamide (1.7 L), and then 1-hydroxybenzotrizole (0.11 Kg, 0.83 mol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.16 Kg, 0.83 mol) were added in. The reaction liquid was heated to 30° C. and stirred for 30 min, then 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.153 Kg, 0.83 mol) was added to the reaction liquid. The reaction liquid was heated to 140° C. and reacted for 2 hours, cooled down to room temperature, and the N,N-dimethylformamide was removed by concentration under reduced pressure. The concentrate was dissolved in ethyl acetate (2.0 L), and washed successively with water (1.5 L×2) and saturated NaHCO3 solution (1.5 L). The organic phase was collected and dried with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 256 g crude product.
[0168] The crude product obtained from above was recrystallized by 1.28 L mixed solvent of methanol and water (a volume ratio of 3:1), crystallized at 20° C., filtered and dried in vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was an almost white solid product (1-5, 182 g, 71% yield). The purity detected by LCMS was 93.1%.
[0169] MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
[0000] (2) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.14 Kg, 0.43 mol) was dissolved in ethyl acetate (1.4 L), and then active manganese dioxide (0.21 Kg, 2.42 mol) was added in. The reaction liquid was heated to reflux and reacted for 3 hours, cooled to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 139 g, 99.0% yield). The purity detected by LCMS was 97.6%.
[0170] MS (ESI): m/z 325.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
[0000] (3) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 60 g, 0.185 mol), azetidine-3-carboxylic acid (1-7, 19.5 g, 0.193 mol) and glacial acetic acid (360 mL, 0.63 mol) were added into methanol (1.6 L) and stirred for 2 hours at 20° C. NaBH3CN (11.5 g, 0.185 mol) was dissolved in methanol (200 mL), and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The dropping temperature was controlled at 15-20° C. The reaction liquid was stirred for 16 hours at 20° C. after dropping and filtered. The filter cake was washed with 300 mL methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (compound 2, 67 g, 89.0% yield). The purity detected by LCMS was 98.8%.
[0171] MS (ESI): m/z 410.2 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 16
Synthesis Method of the Present Invention
[0172] (1) At room temperature, 4-isobutyl benzoicacid (1-4, 1.477 Kg, 8.30 mol) was dissolved in N,N-dimethylformamide (17 L), and then 1-hydroxybenzotrizole (1.12 Kg, 8.30 mol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.58 Kg, 8.30 mol) were added in. The reaction liquid was heated to 30° C. and stirred for 30 min, then 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 1.527 Kg, 8.30 mol) was added to the reaction liquid. The reaction liquid was heated to 140° C. and reacted for 2 hours, cooled down to room temperature, and the N,N-dimethylformamide was removed by concentration under reduced pressure. The concentrate was dissolved in ethyl acetate (20 L), and washed successively with water (15 L×2) and saturated NaHCO3 solution (15 L). The organic phase was collected and dried with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 2.6 Kg crude product.
[0173] The crude product obtained from above was recrystallized by 12.5 L mixed solvent of methanol and water (a volume ratio of 3:1), crystallized at 20° C., filtered and dried in vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was an almost white solid product (1-5, 1.9 Kg, 73% yield). The purity detected by LCMS was 93.89%.
[0174] MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
[0000] (2) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 1.4 Kg, 4.30 mol) was dissolved in ethyl acetate (14 L), and then active manganese dioxide (2.1 Kg, 24.15 mol) was added in. The reaction liquid was heated to reflux and reacted for 3 hours, cooled to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 1.38 kg, 99.0% yield). The purity detected by LCMS was 93.94%.
[0175] MS (ESI): m/z 325.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
[0000] (3) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 0.6 kg, 1.85 mol), azetidine-3-carboxylic acid (1-7, 0.195 kg, 1.93 mol) and glacial acetic acid (0.360 L, 6.3 mol) were added into methanol (16 L) and stirred for 2 hours at 20° C. NaBH3CN (0.115 kg, 1.85 mol) was dissolved in methanol (2 L), and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The dropping temperature was controlled at 15-20° C. The reaction liquid was stirred for 16 hours at 20° C. after dropping and filtered. The filter cake was washed with 3 L methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (compound 2, 0.7 kg, 92.6% yield). The purity detected by LCMS was 97.6%.
[0176] MS (ESI): m/z 410.2 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 17
Synthesis Method of the Present Invention
[0177] (1) At room temperature, 4-isobutyl benzoicacid (1-4, 0.148 Kg, 0.83 mol) was dissolved in N,N-dimethylformamide (1.7 L), and then 1-hydroxybenzotrizole (0.11 Kg, 0.83 mol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.16 Kg, 0.83 mol) were added in. The reaction liquid was heated to 30° C. and stirred for 30 min, then 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.153 Kg, 0.83 mol) was added to the reaction liquid. The reaction liquid was heated to 140° C. and reacted for 2 hours, cooled down to room temperature, and the N,N-dimethylformamide was removed by concentration under reduced pressure. The concentrate was dissolved in ethyl acetate (2.0 L), and washed successively with water (1.5 L×2) and saturated NaHCO3 solution (1.5 L). The organic phase was collected and dried with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 251 g crude product.
[0178] The crude product obtained from above was recrystallized by 1.28 L mixed solvent of methanol and water (a volume ratio of 1:1), crystallized at 20° C., filtered and dried in vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was an almost white solid product (1-5, 158 g, 63% yield). The purity detected by LCMS was 92.1%.
[0179] MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
[0000] (2) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.14 Kg, 0.43 mol) was dissolved in ethyl acetate (1.4 L), and then active manganese dioxide (0.19 Kg, 2.15 mol) was added in. The reaction liquid was heated to reflux and reacted for 3 hours, cooled to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 138 g, 99.0% yield). The purity detected by LCMS was 98.5%.
[0180] MS (ESI): m/z 325.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
[0000] (3) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 60 g, 0.185 mol), azetidine-3-carboxylic acid (1-7, 19.5 g, 0.193 mol) and glacial acetic acid (360 mL, 0.63 mol) were added into methanol (1.6 L) and stirred for 2 hours at 20° C. NaBH3CN (5.8 g, 0.09 mol) was dissolved in methanol (200 mL), and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The dropping temperature was controlled at 15-20° C. The reaction liquid was stirred for 16 hours at 20° C. after dropping and filtered. The filter cake was washed with 300 mL methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (compound 2, 62 g, 81.9% yield). The purity detected by LCMS was 94.6%.
[0181] MS (ESI): m/z 410.2 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 18
Synthesis Method of the Present Invention
[0182] (1) At room temperature, 4-isobutyl benzoicacid (1-4, 0.148 Kg, 0.83 mol) was dissolved in N,N-dimethylformamide (1.7 L), and then 1-hydroxybenzotrizole (0.11 Kg, 0.83 mol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.16 Kg, 0.83 mol) were added in. The reaction liquid was heated to 30° C. and stirred for 30 min, then 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.153 Kg, 0.83 mol) was added to the reaction liquid. The reaction liquid was heated to 140° C. and reacted for 2 hours, cooled down to room temperature, and the N,N-dimethylformamide was removed by concentration under reduced pressure. The concentrate was dissolved in ethyl acetate (2.0 L), and washed successively with water (1.5 L×2) and saturated NaHCO3 solution (1.5 L). The organic phase was collected and dried with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 260 g crude product.
[0183] The crude product obtained from above was recrystallized by 1.30 L mixed solvent of methanol and water (a volume ratio of 1:3), crystallized at 20° C., filtered and dried in vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was an almost white solid product (1-5, 196 g, 76% yield). The purity detected by LCMS was 88.7%.
[0184] MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
[0000] (2) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.14 Kg, 0.43 mol) was dissolved in ethyl acetate (1.4 L), and then active manganese dioxide (0.21 Kg, 2.42 mol) was added in. The reaction liquid was heated to reflux and reacted for 3 hours, cooled to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 139 g, 99.0% yield). The purity detected by LCMS was 97.7%.
[0185] MS (ESI): m/z 325.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
[0000] (3) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 60 g, 0.185 mol), azetidine-3-carboxylic acid (1-7, 19.5 g, 0.193 mol) and glacial acetic acid (360 mL, 0.63 mol) were added into methanol (1.6 L) and stirred for 2 hours at 20° C. NaBH3CN (23.0 g, 0.37 mol) was dissolved in methanol (200 mL), and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The dropping temperature was controlled at 15-20° C. The reaction liquid was stirred for 16 hours at 20° C. after dropping and filtered. The filter cake was washed with 300 mL methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (compound 2, 60 g, 79% yield). The purity detected by LCMS was 94.2%.
[0186] MS (ESI): m/z 410.2 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 19
Synthesis Method of the Present Invention
[0187] (1) At room temperature, 4-isobutyl benzoicacid (1-4, 0.148 Kg, 0.83 mol) was dissolved in N,N-dimethylformamide (1.7 L), and then 1-hydroxybenzotrizole (0.11 Kg, 0.83 mol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.16 Kg, 0.83 mol) were added in. The reaction liquid was heated to 30° C. and stirred for 30 min, then 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.153 Kg, 0.83 mol) was added to the reaction liquid. The reaction liquid was heated to 140° C. and reacted for 2 hours, cooled down to room temperature, and the N,N-dimethylformamide was removed by concentration under reduced pressure. The concentrate was dissolved in ethyl acetate (2.0 L), and washed successively with water (1.5 L×2) and saturated NaHCO3 solution (1.5 L). The organic phase was collected and dried with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 250 g crude product.
[0188] The crude product obtained from above was recrystallized by 1.25 L mixed solvent of methanol and water (a volume ratio of 2:1), crystallized at 20° C., filtered and dried in vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was an almost white solid product (1-5, 169 g, 68% yield). The purity detected by LCMS was 93.9%.
[0189] MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
[0000] (2) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.14 Kg, 0.43 mol) was dissolved in ethyl acetate (1.414, and then active manganese dioxide (0.37 Kg, 4.3 mol) was added in. The reaction liquid was heated to reflux and reacted for 3 hours, cooled to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 139 g, 99.0% yield). The purity detected by LCMS was 99.2%.
[0190] MS (ESI): m/z 325.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
[0000] (3) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 60 g, 0.185 mol), azetidine-3-carboxylic acid (1-7, 19.5 g, 0.193 mol) and glacial acetic acid (360 mL, 0.63 mol) were added into methanol (1.6 L) and stirred for 2 hours at 20° C. NaBH3CN (69.0 g, 1.11 mol) was dissolved in methanol (200 mL), and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The dropping temperature was controlled at 15-20° C. The reaction liquid was stirred for 16 hours at 20° C. after dropping and filtered. The filter cake was washed with 300 mL methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (compound 2, 2, 54 g, 71.2% yield). The purity detected by LCMS was 94.4%.
[0191] MS (ESI): m/z 410.2 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 20
Synthesis Method of the Present Invention
[0192] (1) At room temperature, 4-isobutyl benzoicacid (14, 0.148 Kg, 0.83 mol) was dissolved in N,N-dimethylformamide (1.7 L), and then 1-hydroxybenzotrizole (0.11 Kg, 0.83 mol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.16 Kg, 0.83 mol) were added in. The reaction liquid was heated to 30° C. and stirred for 30 min, then 3-fluoro-N′-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.153 Kg, 0.83 mol) was added to the reaction liquid. The reaction liquid was heated to 140° C. and reacted for 2 hours, cooled down to room temperature, and the N,N-dimethylformamide was removed by concentration under reduced pressure. The concentrate was dissolved in ethyl acetate (2.0 L), and washed successively with water (1.5 L×2) and saturated NaHCO3 solution (1.5 L). The organic phase was collected and dried with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 256 g crude product.
[0193] The crude product obtained from above was recrystallized by 1.28 L mixed solvent of methanol and water (a volume ratio of 1:2), crystallized at 20° C., filtered and dried in vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was an almost white solid product (1-5, 190 g, 74% yield). The purity detected by LCMS was 92.6%.
[0194] MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
[0000] (2) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.14 Kg, 0.43 mol) was dissolved in ethyl acetate (1.4 L), and then active manganese dioxide (0.15 Kg, 1.72 mol) was added in. The reaction liquid was heated to reflux and reacted for 3 hours, cooled to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 139 g, 99.0% yield). The purity detected by LCMS was 96.9%.
[0195] MS (ESI): m/z 325.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
[0000] (3) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 60 g, 0.185 mol), azetidine-3-carboxylic acid (1-7, 19.5 g, 0.193 mol) and glacial acetic acid (360 mL, 0.63 mol) were added into methanol (1.6 L) and stirred for 2 hours at 20° C. NaBH3CN (11.5 g, 0.185 mol) was dissolved in methanol (200 mL), and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The dropping temperature was controlled at 15-20° C. The reaction liquid was stirred for 16 hours at 20° C. after dropping and filtered. The filter cake was washed with 300 mL methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (compound 2, 64 g, 84.4% yield). The purity detected by LCMS was 95.5%.
[0196] MS (ESI): m/z 410.2 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
Example 21
Synthesis Method of the Present Invention
[0197] (1) At room temperature, 4-isobutyl benzoicacid (14 0.148 Kg, 0.83 mol) was dissolved in N,N-dimethylformamide (1.7 L), and then 1-hydroxybenzotrizole (0.11 Kg, 0.83 mol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.16 Kg, 0.83 mol) were added in. The reaction liquid was heated to 30° C. and stirred for 30 min, then 3-fluoro-N-hydroxy-4-hydroxymethyl benzamidine (1-3, 0.153 Kg, 0.83 mol) was added to the reaction liquid. The reaction liquid was heated to 140° C. and reacted for 2 hours, cooled down to room temperature, and the N,N-dimethylformamide was removed by concentration under reduced pressure. The concentrate was dissolved in ethyl acetate (2.0 L), and washed successively with water (1.5 L×2) and saturated NaHCO3 solution (1.5 L) The organic phase was collected and dried with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 258 g crude product.
[0198] The crude product obtained from above was recrystallized by 1.29 L mixed solvent of methanol and water (a volume ratio of 3:1), crystallized at 20° C., filtered and dried in vacuum to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol which was an almost white solid product (1-5, 186 g, 72% yield). The purity detected by LCMS was 93.8%.
[0199] MS (ESI): m/z 327.0 [M+H] + . NMR: 1 HNMR (400 MHz, CDCl3) δ: 8.11 (d, J=8.0 Hz, 2H), 7.98 (m, 1H), 7.86 (m, 1H), 7.59 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 4.85 (s, 2H), 2.57 (d, J=6.8 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.8 Hz, 6H).
[0000] (2) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl alcohol (1-5, 0.14 Kg, 0.43 mol) was dissolved in ethyl acetate (2.8 L), and then active manganese dioxide (0.21 Kg, 2.42 mol) was added in. The reaction liquid was heated to reflux and reacted for 3 hours, cooled to room temperature and filtered. A light yellow filtrate was collected, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde which was a white solid product (1-6, 138 g, 99% yield). The purity detected by LCMS was 98.8%.
[0200] MS (ESI): m/z 325.0 [M+H] + , NMR: 1 HNMR (400 MHz, CDCl3) δ: 10.42 (s, 1H), 8.12˜7.99 (m, 5H), 7.34 (d, J=7.2 Hz, 2H), 2.58 (d, J=6.4 Hz, 2H), 1.93 (m, 1H), 0.93 (d, J=6.4 Hz, 6H).
[0000] (3) At room temperature, 2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzaldehyde (1-6, 60 g, 0.185 mol), azetidine-3-carboxylic acid (1-7, 19.5 g, 0.193 mol) and glacial acetic acid (360 mL, 0.63 mol) were added into methanol (1.6 L) and stirred for 2 hours at 20° C. NaBH3CN (11.5 g, 0.185 mol) was dissolved in methanol (200 mL), and then the solution of NaBH3CN in methanol was added dropwise into the reaction system within 1 hour. The dropping temperature was controlled at 15-20° C. The reaction liquid was stirred for 16 hours at 20° C. after dropping and filtered. The filter cake was washed with 300 mL methanol and then dried to obtain 1-{2-fluoro-4-[5-(4-isobutylphenyl)-1,2,4-oxadiazol-3-yl]-benzyl}-3-azetidine carboxylic acid which was a white solid product (compound 2, 64 g, 84.5% yield). The purity detected by LCMS was 96.9%.
[0201] MS (ESI): m/z 410.2 [M+H] + . NMR: 1HNMR (400 MHz, CDCl3) δ: 8.13 (d, J=8.4 Hz, 2H), 8.05 (m, 1H), 7.97 (m, 1H), 7.68 (t, J=8.0 Hz, 7.6 Hz, 1H), 7.42 (d, J=8.4 Hz, 2H), 4.40 (s, 2H), 4.15 (m, 4H), 3.41 (m, 1H), 2.61 (d, J=7.2 Hz, 2H), 1.95 (m, 1H), 0.94 (d, J=7.2 Hz, 6H).
[0202] The above description for the embodiments of the present invention is not intended to limit the present invention, and those skilled in the art can make various changes and variations according to the present invention, which are within the protection scope of the present invention without departing from the spirit of the same. | The present invention provides a compound represented by formula I, wherein R is a halogen element or a C1-C6 alkyl group. The compound has S1P1 receptor agonist activity and selective specificity and has obviously-shortened half-life in-vivo, and therefore the compound is a high-quality second-generation S1P1 receptor agonist. The present invention also provides a use of the compound in preparing medicine for treating diseases or symptoms mediated by an S1P1 receptor, a pharmaceutical composition comprising the compound, and uses of the compound and the pharmaceutical composition in treating diseases or symptoms mediated by the S1P1 receptor. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to apparatus for the projection by means of a lance of refractory and other material, particularly in metallurgic plant and specifically, in converters. This process is generally called "gunning".
The known processes for the repair or internal relining of converters consist in the application by various methods of a refractory material to the refractory base of the lining which is part worn or has deteriorated.
This is usually carried out manually without precision which leads to an enormous loss of time and material and makes it at least necessary to incline the converter and then remove the slag.
In Patents BE 849524 (Kurosaki Refractories Ltd.) and U.S. Pat. No. 3,827,633 (H. Koundo and S. Kubo) there is described a mobile apparatus in which a lance is movable in an oscillating sleeve which itself can pivot ultimately on a supporting column. The state of the art can be further illustrated by Patent Nos. DE 2 200 667 ( Donezkig), FR 1,528,137 (Demag), U.S. 3,351,289 (Demaison) and AU 422,354.
It should be noted however that most of the modern processes for maintaining converters require the slag to be retained in the converter which makes it difficult to repair certain parts of the converter, particularly those located between the discharge opening and the slag bath. The apparatuses of the prior art include just this inconvenience of not permitting easy access to all these parts without inclining the converter to such an extent that it is impossible to maintain a substantial pocket for slag in the converter.
SUMMARY OF THE INVENTION
The present invention therefore aims at providing apparatus for the relining, repair, and preventive maintenance of metallurgical plant such as converters in a simple and speedy way and obviating the difficulties of access to certain parts of the plants.
This object is achieved according to the invention with the aid of a mobile apparatus carrying an articulated arm capable of rotating about its base and supporting a lance holder on which can slide at least one retractible lance and which is characterised in that the lance-holder is articulated to a scissor like arm of which the opening is adjustable by an actuator.
The said actuator for the opening may be formed by an hydraulic jack or a purely mechanical system.
The elements of the lance are preferably designed in such a way as to include a double jacket in which is circulated a cooling fluid which is preferably water so that one can operate in the conditions of high temperature present in a converter.
The apparatus preferably comprises a complete installation providing for the projection of a mixture of solid matter with the addition of any desired quantity of water etc. and the material necessary to ensure the complete independence of the apparatus.
The lance may be designed in such a way as to be formed by a primary element (primary lance) in which can slide telescopically a secondary element (secondary lance), the said primary element itself sliding on the lance holder.
The displacement of the different elements of the lance, that is to say the movement of the secondary lance relative to the primary lance, and the movement of that relative to the lance holder is conveniently affected by an actuator through a cable or chain. Actuation by an endless screw, rack, or other mechanism is also possible.
According to one particularly advantageous embodiment of the apparatus of the invention, a cabin for the single operator ensuring the positioning of the machine and the operation of gunning itself is rigid with the lance carrier and located at one side of it in such a way that the operator is practically always located in the line of action of the lance.
The last element of the lance, that is to say the extremity which penetrates into the metallurgical plant may be fitted as desired with different nozzles according to the nature of the work and of the material to be projected and is rotatable to provide a suitable distribution of the repairing material.
The invention equally applies to the use of the apparatus of which the main features have been described for the relining and repair of metallurgical plant and particularly the interior of a converter and the discharge opening thereof.
Other characteristics and specified advantages of the apparatus in accordance with the invention will appear in the description which follows with reference to the annexed drawings illustrating by way of non-limiting example one preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a side view (right side) arranged for travel on the working platform of converters.
FIG. 2 is a view in a position partially opened out in which the lance carrier is set at right angles to the longitudinal axis of the supporting vehicle which is seen from the back.
FIG. 3 is a view partially opened out and corresponding to FIG. 2, the vehicle being seen from the front.
FIG. 4 is a detail view of the front part and the rear part of a lance having two elements with the secondary lance retracted into the primary lance and the middle part omitted to limit the complication of the drawing.
FIG. 5 is an enlarged view of the front of the primary lance shown in FIG. 4.
FIGS. 6 and 7 are respectively sections on A-A and B-B of FIG. 4.
FIGS. 8 and 9 are respectively sections on the lines C-C and D-D of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawings the same reference marks are used for the same elements in the different views. The terms front, rear, left and right relate to the position of the operator in his cabin when the apparatus is in the folded position.
The apparatus is formed by a chassis 1 equipped with wheels 3 at the front and a double row of rollers 5 at the back, the assembly of wheels 3 being provided with a differential and driven by a motor while the rollers 5 are orientable to ensure complete mobility of the apparatus on the platform 7 surrounding the converters.
The chassis 1 carries one part of the means for relining and repairing the converter and also the refractory material used for that purpose and the control for the relining means as well as the different driven groups.
There is shown in FIG. 1 a hopper 41 holding dry, pre-wetted or pre-coated refractory material, which is transported by pneumatic mechanism 43 towards the projection lance.
The means for the relining or repairing comprises a secondary lance 4 designed for penetrating into the converter, sliding in a primary lance 12 which itself slides on a lance carrier 13 supported by an articulated scissor 15 formed by two elements 15a and 15b, this scissors 15 being itself supported by a pivoting column 17 (FIG. 2).
The normal working position of the apparatus is that shown in FIGS. 2 and 3, that is to say in which the lance carrier 13 finds itself approximately at right angles to the longitudinal axis of the supporting vehicle.
The pivoting column 17 allows the orientation of the lance carrier 13 to be varied between its operational position and the folded position permitting displacement of the vehicle on the working platform 7 and also permits direction of the lance when it is introduced into the converter.
The two parts 15a and 15b of the scissors comprise an articulation joint 21 permitting the angle of opening of the scissors under the influence of the jack 23 pivotally connected between the points 25 and 26 respectively provided on the parts 15a and 15b of the scissors.
A second jack 27 connected between the pivot points 29 and 30 respectively provided on the part 15a of the scissors and the lance carrier 13 permits the angular orientation of the lance carrier to be varied with respect to the said part 15a.
The lance is formed by at least two telescopic elements 11 and 12 in which circulates a cooling fluid which is preferably water.
The control of the different elements of the telescopic lance (elements 11 and 12) is obtained by a system of cable and chain (not shown) the outward movement of the primary lance automatically taking with it the outward movement or return of the secondary lance.
On the lance carrier 13 there is mounted a control cabin 39 which is located as near as possible to the longitudinal axis of the lance carrier 13 and of the lance 11 in such a way that the operator can follow the movement of this.
The movement of the lance carrier 13 and of the cabin 39 with which it is rigid is illustrated between raised position shown in full lines in FIG. 2 and a lowered positon shown in broken lines in the same figure.
The primary lance is formed by a tube with double walls 12a and 12b (FIGS. 4 to 9).
In the space between the walls 12a and 12b are received on the one hand a bush 53 for an operating axle for rotating the secondary lance 11 and a conduit 57 for leading the cooling fluid towards the end of the primary lance, the cooling fluid returning to the carrying apparatus in the space 55 formed by the double walls.
In the secondary lance 11 there is provided a conduit 61 for the passage of the refractory material, two conduits 63 and 64 of a circuit for the entry and discharge of a fluid for cooling the lance and a conduit 65 for feeding water or other additive to the projecting nozzle.
A housing 56 at the end of the primary lance 12 contains a shaft 54 located in the sheath 53 rigid with a pinion 80 which drives my means of a double chain 81 a pinion 82 keyed on the secondary lance 11 (FIG. 9). Thus, rotation of shaft 54 causes secondary lance 11 to be rotated relative to the primary lance 12. The secondary lance 11 may incorporate deflecting nozzles for directing the refractory material to any point of the converter into which the nozzle is introduced.
The secondary lance 11 may be extended outwardly from the primary lance 12 as stated previously. Rollers 51 (FIGS. 4 and 6) and 52 (FIGS. 5 and 8) act to guide and support the secondary lance 11 within the primary lance 12. The rollers 51, 52 are also formed in such a manner that the rotation of the secondary lance 11, mentioned previously, within the primary lance 12 by the action of the pinions 80, 81 and the chain 82 is facilitated.
The technical process obtained by the present invention lies in the possibility of reaching, by simple control of a scissors, parts of a converter which are difficult of access.
By combining this scissors arrangement with a transmission for rotating the lance equipped at its extremity with deflecting nozzles for the projected material it becomes possible in practice to reach any location whatever of the converter, angularly as well as vertically.
The advantage of the scissor arrangement with the joints described is to permit not only any angular disposition but equally a variation in height limited only by the total travel of the jacks, which has not been foreseen by the apparatus in the state of the art. For this reason the apparatus in accordance with the invention can be used for gunning any surfaces whatsoever and in particular special furnaces and elements in steelworks.
A complementary advantage follows from the particular disposition of the control cabin because it is located substantially on the longitudinal axis of the lance carrier and of the lance which allows the operater to see at all times the movement of the lance and to follow the projection of the refractory material. He can therefore by simple actions modify the angle of the lance and direct the projection as he wants it.
Another advantage of the arrangement is its autonomous character which groups together the functions of movement of the apparatus on the ground, the control of the positioning of the lance, and the projection of the refractory material. The power can be provided from any outside totally independent source for an autonomous motor on the apparatus and/or by a simple electric cable connected to the system.
The apparatus can be mounted equally well on rails as on roads. It can also be connected to an external source of compressed air or carry a self-contained compressor for pneumatic projection of the refractory material.
Although there has been described embodiments of the invention which are specially preferred it should be understood that variation and modification are available to one skilled in the art while remaining within the field of the invention. | Disclosed is an apparatus for the projection of refractory and other material for the relining and repair of a metallurgical plant, particularly converters. The apparatus comprises an articulated arm capable of pivoting on its base and supporting a lance carrier in which a telescopic, retractable lance is mounted. The lance carrier is articulated on an arm acting in the manner of a scissor, the movement of which is effected by two jacks. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation application of U.S. patent application Ser. No. 09/983,537 filed Oct. 24, 2001, which is based on, and claims domestic priority benefits under 35 USC §119(e) from U.S. Provisional Application Ser. No. 60/242,457 filed Oct. 24, 2000, each of which the entire content thereof is expressly incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to bioprosthetics. In especially preferred embodiments, the present invention is related to bioprosthetics formed in situ.
BACKGROUND AND SUMMARY OF THE INVENTION
The vertebral disc is a collagenous spacer positioned between the vertebral bones of the spinal column. The disc generically consists of a tough fibrillar outer annulus (annulus fibrosus) and a highly hydrated gelatinous core (nucleus pulposus). The vertebral disc serves as a shock absorber to dissipate the energy of impact loading on the back, as well as a joint, allowing flexion and extension of the human torso.
Degeneration of vertebral disc function in the lumbar portion of the spine is the leading cause of debilitating low back pain in adults over the age of 35. Degenerative disc disease (DDD) is characterized by a gradual collapse of the vertebral disc due to dehydration of the nucleus pulposus, or by a bulging of the annulus fibrosus. DDD may also precipitate the formation of fissures within the annulus that allows extrusion of the disc nucleus (disc herniation) resulting in a sudden collapse in the disc height and the potential for nerve root and/or spinal cord compression. Disc herniation may also result due to trauma related over compression of the spine, such as a heavy sitting fall.
Chronic diffuse low back pain results from irritation of pain receptors in the outer third of the disc annulus and surrounding soft tissues as the disc collapses. Radicular pain results from direct compression of the affected nerve root by extruded or bulging disc tissue. Aggressive and extensive physical therapy and drug treatments are the first line treatments for debilitating back pain. In the absence of acceptable pain resolution, surgical intervention is indicated.
The traditional surgical procedures for treatment of intractable low back pain due to DDD call for either fusion of the vertebral bodies above and below the affected disc, or removal of the nuclear material thorough open surgical, micro-surgical or endoscopic procedures. Recently, novel procedures involving thermal shrinkage of the collagenous lamina with an electrothermal catheter or laser device have been applied. The removal of the nucleus leaves a void within the disc, and eliminates the viscoelastic fluid that acts as a shock absorber. This void and absence of the viscoelastic fluid creates an opportunity for the lamina to collapse inward and allows the disc space to collapse further. The collapse of the disc space can lead to loss of motion and morbidity, as during the collapse of the disc space the nerves radiating from the spinal column may be pinched.
Many surgical techniques and specialized devices have been generated to combat the problem of progressive disc collapse resulting from disc denucleation. Harvested autologous bone has been placed within the denucleated disc space to afford a bony bridge or fusion between the two vertebral bodies. Pedicle screws and other spinal instruments, such as rods and plates, are mechanically affixed to the vertebral bodies, stabilizing the vertebra and preventing further collapse. The problem with these, and other fusion techniques, is the prevention of motion at the level of repair, and resultant transfer of stresses to the levels above and below. These additional loading stresses inevitably result in the degeneration of these disc levels as well.
The patent literature discloses several apparati for the replacement of an entire disc (i.e., prosthetic vertebral disc), whereby the damaged disc is removed and a device is anchored to the vertebral bone below and above the damaged disc. The ultimate goal of such a design concept is to maintain or regain the mobility of the native vertebra-disc-vertebra motion segment. Varying degrees of mobility have been claimed for different types of mechanical disc replacements. The following is a non-exhaustive list of such U.S. Patent disclosures: 1 U.S. Pat. No. 4,309,777 to Patil; U.S. Pat. No. 5,865,845 to Thalgott; U.S. Pat. No. 5,827,328 to Buttermann; U.S. Pat. No. 5,865,846 to Bryan et al; U.S. Pat. No. 4,759,766 to Buettner-Jantz et al.; U.S. Pat. No. 5,071,437 to Steffe; U.S. Pat. No. 4,911,718 to Lee et al.; and U.S. Pat. No. 4,714,469 to Kenna. The utility of these prior design proposals has been principally limited by an inability to adequately anchor the flexible prosthetic disc to the bony vertebra. 1 The entire disclosure of each U.S. Patent cited hereinafter is hereby expressly incorporated hereinto by reference.
An alternate approach to the repair of damaged or diseased vertebral discs is to physically prevent disc collapse through the insertion of a rigid body into the disc space. The insertion of tubular or other hollow devices, that may, in addition, contain openings through their walls to allow bone growth through the device, enable the motion segment to be fused with the vertebral spacing maintained. These open or tubular devices may be constructed of metallic alloys traditional to implantable medical devices (e.g., stainless steel, titanium and titanium alloys), carbon fiber reinforced engineering thermoplastics (e.g., polyetheretherketones), or machined human cortical bone. These devices have been disclosed, for example, in U.S. Pat. No. 4,961,740 to Ray et al; U.S. Pat. No. 5,015,247 to Michelson; U.S. Pat. No. 5,766,253 to Brosnahan; U.S. Pat. No. 5,425,772 to Brantigan; and U.S. Pat. No. 5,814,084 to Grivas et al. While these devices may retain the proper spacing between the vertebra (i.e., the disc height), they are disadvantageous since, as the two vertebrae are fused, motion across the vertebra-disc-vertebra element is eliminated.
Another general technique for the preservation of vertebral body separation is to replace the removed disc nuclear tissue with non-fusing, non-rigid materials. One prior proposal suggests using a bladder that can be filled with liquid to restore disc height (see, U.S. Pat. No. 3,875,595 to Froning). One other prior proposal is disclosed in U.S. Pat. No. 5,534,028 to Bao et al, where a pre-cast pre-shaped hydrogel in placed into the void. Variations on the type of device disclosed in Bao et al '028 are likewise disclosed in U.S. Pat. No. 5,976,186, U.S. Pat. No. 5,192,326, and U.S. Pat. No. 5,047,055. Preformed inserts made from a xerogel plastic as a nucleus pulposus replacement have also been disclosed in U.S. Pat. No. 6,264,695. A cylindrical hydrogel pillow that is contained within a non-expanding casing and assorted variations thereof are described in U.S. Pat. No. 4,772,287, U.S. Pat. No. 4,904,260, U.S. Pat. No. 5,674,295, U.S. Pat. No. 5,824,093, and U.S. Pat. No. 6,022,376. In this regard, the device shown in U.S. Pat. No. 6,022,376 is inserted into tunnels drilled into the disc as a dehydrated hydrogel resin, and is allowed to rehydrate and swell once it is inserted. The swelling holds the device in place while preventing the collapse of the denucleated disc. However, the device is neither chemically nor mechanically fixated in place.
It has also been disclosed in U.S. Pat. Nos. 6,183,581, 6,206,921 and 6,264,659, that molten gutta percha and its compounds may be used as possible replacements of nucleus pulposus.
Broadly, the present invention relates to bioprosthetic devices comprised of an exterior biological tissue member which at least partly defines a cavity, and a proteinaceous biopolymer which fills the cavity, and intercalates is chemically bound (linked) to the surrounding biological tissue member. In preferred forms, the bioprosthetic device is a bioprosthetic vertebral disc having a fibrillar outer annulus which surrounds and defines an interior cavity and is formed by removal of at least a substantial portion of the natural gelatinous core therefrom. The cavity defined by the fibrillar outer annulus may then be filled with a flowable biopolymeric material which is then allowed to at least partly solidify in situ (e.g., most preferably by in situ cross-linkage reaction) to form a proteinaceous biopolymer within the cavity.
The flowable biopolymeric material is most preferably a liquid mixture liquid mixture comprised of human or animal-derived protein material and a di- or polyaldehyde. When introduced into the cavity of the tissue member, therefore, the liquid mixture may then react to form a cross-linked biopolymer in situ within the cavity thereby forming a bioprosthetic device therein. The liquid mixture may be formed in advance of being introduced into the cavity, or may be formed simultaneously during introduction into the cavity.
These and other aspects and advantages will become more apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Reference will hereinafter be made to the accompanying drawing FIGURE which schematically depicts a portion of a patient's vertebral column showing a vertebral disc bioprosthetic in accordance with the present invention interposed between adjacent vertebrae.
DETAILED DESCRIPTION OF THE INVENTION
As used herein and in the accompanying claims, the term “bioprosthetic device” and like terms mean a combination comprised of a biological tissue member and a proteinaceous biopolymer which is chemically bound (linked) to the tissue of the tissue member.
The accompanying drawing FIGURE shows a segment of a patient's vertebral column VC wherein vertebral disc bioprosthetics 10 in accordance with the present invention are interposed between adjacent ones of the individual vertebrae V. The vertebral disc bioprosthetics 10 essentially include the fibrillar outer annulus 10 - 1 of the patient's natural vertebral disc following removal of the gelatinous core. The fibrillar outer annulus 10 - 1 thus bounds and defines an inner cavity into which a proteinaceous biopolymer 10 - 2 is injected in situ. The proteinaceous biopolymer (usually referred to hereinafter more simply as the “biopolymer”) 10 - 2 thus fills completely the void space left following removal of the natural gelatinous core of the patient's natural vertebral disc. The biopolymer 10 - 2 thus acts as a shock-absorber of sorts similar to the natural functions attributable to the removed gelatinous core.
Virtually any suitable proteinaceous biopolymer may be employed in the practice of the present invention. In this regard, the term “proteinaceous biopolymer” and like terms mean a polymeric or copolymeric material which contains one or more units in the polymer chain comprised of natural, synthetic or sequence-modified proteins or polypeptides, and mixtures and blends of such polymeric and/or copolymeric materials.
One especially preferred biopolymer 10 - 2 that may be employed in the practice of this invention is a cross-linked reaction product of a two part mixture initially comprised of:
Part A: a water-soluble proteinaceous material of about 27-53% by weight of the mixture, and Part B: di- or polyaldehydes present in a weight ratio of one part by weight to every 20-60 parts of protein present by weight in the mixture and water, optionally containing non-essential ingredients to make up the balance of the composition.
Part A of the mixture is most preferably substantially an aqueous solution of a proteinaceous material of human or animal origin. Albumins including ovalbumins are preferred proteins, and serum albumins of human or animal origin are particularly preferred. The proteinaceous material may be a purified protein or a mixture in which the proteins such as serum albumins are the predominant ingredients. For example, the solid mixtures obtained by dehydration of blood plasma or serum, or of commercial solutions of stabilized plasma proteins, can be used to prepare Part A. These mixtures, generally referred to as plasma solids or serum solids, are known to contain albumins as their major ingredients, of the order of 50-90%. As used herein, the term “plasma” refers to whole blood from which the corpuscles have been removed by centrifugation. The term “serum” refers to plasma which has additionally been treated to prevent agglutination by removal of its fibrinogen and/or fibrin, or by inhibiting the fibrin clot formation through addition of reagents, such as citrate or EDTA. The proteinaceous material may also contain an effective amount of hemoglobin.
Part B is substantially an aqueous solution of di- or polyaldehydes. A wide range of these substances exist, and their usefulness is restricted largely by availability and by their solubility in water. For example, aqueous glyoxal (ethandial) is useful, as is aqueous glutaraldehyde (pentandial). Water soluble mixtures of di- and polyaldehydes prepared by oxidative cleavage of appropriate carbohydrates with periodate, ozone or the like are also useful. Glutaraldehyde is the preferred dialdehyde ingredient of Part B. When Parts A and B are brought together, the resultant product rapidly hardens to a strong, flexible, leathery or rubbery material within a short time of mixing, generally on the order of 15-30 seconds. The most preferred material for use in the present invention is commercially available from CryoLife, Inc. of Kennesaw, Ga. under the registered trademark “BIOGLUE”. (See also, U.S. Pat. No. 5,385,606, the entire content of which is expressly incorporated hereinto by reference.)
The two components A and B noted above are either premixed and then applied, or simultaneously mixed and delivered through an in-line mixing/dispensing tip during the filling of the tissue-defined cavity. Upon reaction of the two components, the resulting biomaterial is a hydrogel that adheres to the surrounding tissue, intercalates into the voids of the surrounding tissues, is space filling, and is mechanically and biologically stable for some time. The material may be solid or sponge-like in appearance. Furthermore, it may contain organic or inorganic salts or other particulate matter to modify the physical properties of the resulting bioprosthetic device. Preferably, the biopolymer 10 - 2 will exhibit compressive strengths of at least 300 kPa (preferably between about 300 to about 600 kPa) and compressive moduli of 2.5 MPa, and creep moduli of 1.0 MPa. The ultimate compressive strength of the biopolymer 10 - 2 can be adjusted by altering the composition of the protein and cross-linker components and/or through the addition of various fillers.
As noted previously, the proteinaceous biopolymer that may be employed in the practice of the present invention may be include as on reactable component a natural, synthetic or sequence-modified (i.e., so-called “engineered”) polypeptides (e.g., as disclosed more fully in U.S. Pat. No. 6,018,030; U.S. Pat. No. 5,374,431; U.S. Pat. No. 5,606,019; or U.S. Pat. No. 5,817,303, incorporated fully by reference herein). Thus, although many of the following examples employ albumin, it will be understood by those in this art that other reactable components may be employed satisfactorily. Reactable synthetic polymeric components, namely, those which contain functional groups to cause cross-linking (e.g. polyethylene-glycol polymers derivatized with electrophilic and nucleophilic groups such as amine, succinimidyl, anhydride, thiol) may also be employed in the practice of the present invention. See in this regard, U.S. Pat. No. 6,166,130; U.S. Pat. No. 6,051,648; or U.S. Pat. No. 5,900,245, the entirety of each being expressly incorporated hereinto by reference.
Nominal compressive mechanical properties that are obtained are similar to those of vertebral discs and lumbar vertebra. The compressive properties of the described biomaterial 10 - 2 are very different from highly rigid materials traditionally used as implantable structural elements such as stainless steel, titanium, polyacrylate bone cements, ceramics or carbon fiber composites, and hence allow for better biomechanical compatibility in selected indications. For example, the bioprosthetic vertebral discs of the present invention exhibit flexibility comparable to the biologically natural vertebral disc. More specifically, the bioprosthetic vertebral discs of the present invention exhibit flexibility comparable to the biologically natural vertebral disc after being subjected to at least about 5 million cycles of a cyclic load of about 0.85 MPa
The particular properties of the biopolymer 10 - 2 can be “engineered” to suit specific end uses. For example, the biopolymer may include fibrous or particulate reinforcement (“filler”) material, provided it is biocompatible.
Thus, natural or synthetic fibers, such as polyesters, nylons, polyolefins, glass and the like of virtually any desired denier may be employed. Furthermore, the reinforcing fibers may be used in the form of a continuous length of single fibers (i.e., monofilaments) or a yarn, roving or rope of multiple filaments. Moreover, the reinforcing media may be in the form of staple fibers of predetermined lengths which are spun into yarns, rovings and/or ropes of desired denier and continuous length. The mono- or multifilamentary reinforcing materials may also be in the form of woven or non-woven fabric structures. Suffice it to say here, that virtually any physical form of fibrous reinforcing material may be satisfactorily employed in the practice of the present invention.
The reinforcing material may also be in the form of particulates, such as synthetic or natural organic and inorganic particulate reinforcement materials. Some representative examples of such particulates include calcium carbonate, calcium phosphate, hydroxyapatite bone chips, ceramic particles and the like.
The present invention will be further described with reference to the following non-limiting Examples.
EXAMPLES
Example 1
A formulation formed of a protein solution (serum albumin) and a cross linker (gluteraldehyde) was contained in the separate chambers of a delivery device. When the device is triggered, the two components are expelled from their respective chambers into a mixing tip that combines the two solutions and mixes them as they travel over the static mixing elements present in the tip. A medical needle was attached to the mixing tip and the formulation injected into the distal space between the vertebra of an explanted pig spine. The tip can be attached to a needle, catheter, or other hollow tubular device for delivery, for example. After 30 seconds, the needle was withdrawn from the injection site. The material that was injected had polymerized in place and did not exude out of the needle hole. After 2 minutes, the disc-vertebra plate was dissected and the presence of the biomaterial seen.
Example 2
Bovine calf spines were obtained from a commercial slaughterhouse and cleaned by blunt and sharp dissection to expose the vertebral bodies and the discs. A 4 mm hole was made into the anterior face of the disc and the drill bit allowed to enter to the center of the nucleus. The nuclear material was removed using surgical forceps and curettes. The hollow space was filled with the formulation described in Example 1. The material that was injected polymerized in place and did not exude out of the hole. After 2 minutes the disc-vertebra plate was dissected and the presence of the biomaterial seen.
Example 3
Bovine calf spines were obtained from a commercial slaughterhouse and cleaned by blunt and sharp dissection to expose the vertebral bodies and the discs. The top and bottom of the vertebral bodies were cut parallel to each other at mid-height using a miter box to yield a bone/disc/bone motion segment. A 4 mm hole was made into the anterior face of the disc and the drill bit allowed to enter into the center of the nucleus. The nuclear material was removed using surgical forceps and curettes. The hollow space was filled with the formulation described in Example 1. The material that was injected had polymerized in place and did not exude out of the hole.
Once polymerization had occurred, the construct could be compressed by hand in the front-back and left-right axes, indicating flexibility was retained after repair of this segment. Then, the construct was placed in a biomaterials testing device (Instron electromechanical test station) and compressed repeatedly to a load of 700 N to condition the construct. Thereafter, a constant load of 700 N was applied to measure compressive creep. The load was held for 10 min. During this time, the polymerized material did not exit from the distal space or the hole. A force of 700 N is the published literature value for the load a lumbar spinal disc experiences when a person of average built is standing upright. The experiment was repeated on 5 separate samples.
In this example, the motion segment height was measured before removal of the nucleus, after removal of the nucleus, after filling with the biomaterial, and after loading and releasing the load. It was found that (1) the removal of the nucleus reduced the overall height of the material, as well as the compressibility, (2) the filling with the biomaterial restored the disc height and the compressibility.
Example 4
A disc of biomaterial formed by injecting a volume of material with the formulation described in Example 1 into a cavity mold was compressed for 100 and 1000 cycles at a compression rate of 100 mm/min between a minimum stress of 200 kPa and a maximum stress of either 470 or 800 kPa (equivalent to a normal lumbar disc, cross sectional area of 1500 mm 2 , loaded between 300 N and 700 or 1200 N). The disc element did not exhibit fracture, permanent deformation, or demonstrate a loss of hydration (by mass loss analysis). A force of 1200 N is the published literature value for the compressive load a lumbar spinal disc experiences when a person of average built flexes forward.
Example 5
Bovine calf spines were obtained and prepared as described in Example 3. In this example, the nucleus pulposus was accessed either from an anterior or a posterolateral direction. The constructs were then placed under a cyclic load of 0.85 MPa at 5 Hz and the load applied for >5 million cycles. During this time, the constructs were kept in physiological saline solution containing a non-fixative biocidal agent. At the end of the test period, the constructs were removed and the disc sliced parallel to the end plates to observe the status of the implants. The implant present in the cavity created by the removal of the nucleus pulposus, was intact and flexible.
Example 6
Samples of the biomaterial were formed as described in Example 4. The biomaterial was then placed under a cyclic load of 0.5 MPa at approximately 2 Hz and the load applied for either >5 million cycles or >10 million cycles. During this time, the constructs were kept in physiological saline solution containing a non-fixative biocidal agent. The test samples remained intact throughout the duration of the test, and demonstrated <10% loss in original height.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | Bioprosthetic devices include an exterior biological tissue member which at least partly defines a cavity, and a proteinaceous biopolymer which fills the cavity, and intercalates and is chemically bound (fixed) to the tissue of the surrounding biological tissue member. In preferred forms, the bioprosthetic device is a bioprosthetic vertebral disc having a fibrillar outer annulus which surrounds and defines an interior cavity and is formed by removal of at least a substantial portion of the natural gelatinous core therefrom. The cavity defined by the fibrillar outer annulus may then be filled with a flowable proteinaceous biopolymer. Preferably, the proteinaceous biopolymer is a liquid mixture comprised of human or animal-derived protein material and a di- or polyaldehyde, which are allowed to react in situ to form a cross-linked biopolymer within the cavity. The liquid mixture may be formed in advance of being introduced into the cavity, or may be formed simultaneously during introduction into the cavity. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is a National Phase entry under 35 USC 371 and claims priority as provided in 35 USC 120 to PCT/EP2015/061543 having an International Filing Date of May 26, 2015 and a Priority Date Claimed of Jun. 2, 2014, incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates to a cartridge flange for fitting filter cartridges in filter systems, in particular industrial suction-extraction systems or air-filter systems.
BACKGROUND OF THE INVENTION
[0003] Cartridge flanges of this type are usually part of a filter cartridge, in particular for suction-extraction systems or filter systems, respectively, in the industrial or commercial sector. The cartridge flange herein serves for connecting a filter cartridge in an exchangeable manner to a master suction-extraction system or filter system. A filter fabric, for receiving dust or the like, which in many instances is cylindrically configured and optionally folded and which hereunder is referred to as the filter unit, is usually connected to the cartridge flange.
[0004] As per the prior art, there is a very wide variety of filter systems for each of which correspondingly matching filter cartridges and thus cartridge flanges have to be kept readily available. The procurement and stocking of corresponding filter cartridges thus cause a significant investment in terms of logistics.
SUMMARY OF THE INVENTION
[0005] It is an object of the invention to provide a cartridge flange which, on the one hand, may be used in a universal manner and, on the other hand, may be used especially for a specific type of filter systems, in particular industrial suction-extraction systems or air-filter systems.
[0006] This object is achieved by a cartridge flange having the features as claimed in the independent and dependent claims provided herein. The dependent claims relate to advantageous variants and embodiments of the invention.
[0007] It is a further object of the invention to achieve a filter system which is provided with a cartridge flange which, on the one hand, may be used in a universal manner and, on the other hand, may be used especially for a specific type of filter systems, in particular industrial suction-extraction systems or air-filter systems.
[0008] A cartridge flange according to the invention, in particular for fitting a filter cartridge for filter systems, in particular industrial suction-extraction systems or air-filter systems, has an annular basic shape and at least one lug which is configured on the external circumference and which has at least one opening for receiving a bolt for fastening the filter cartridge to the filter system. The lug herein is configured in such a manner that bolts having dissimilar radial spacings from an imaginary center of the annular shape of the cartridge flange may engage for final fastening of the cartridge flange.
[0009] It is thus ensured by the solution according to the invention that a single filter cartridge may be used for suction-extraction systems which have dissimilar spacings of receptacle bolts for receiving filter cartridges from an imaginary center of an annular cartridge flange, such that, if applicable, only one size of filter cartridges having the corresponding specification according to the invention has to be kept readily available within a plant in which various suction-extraction systems are employed.
[0010] Additionally, the lug of a cartridge flange according to the invention may be configured in such a manner that a bolt may engage depending on the rotational orientation of the cartridge flange.
[0011] A comparatively simple potential for fitting of a cartridge flange according to the invention in a master system results from this variant. According to the variant described, it may be achieved by simple twisting in a specific direction or by a specific angular range that the cartridge flange is reliably connected to the suction-extraction system or the filter system, respectively. That is to say that identical filter cartridges which from one system to the other differ only in terms of the radial orientation of said filter cartridges in relation to the overall system are installed in suction-extraction systems or filter systems, respectively, having dissimilar bolt spacings.
[0012] In one preferred embodiment of a cartridge flange according to the invention, the at least one opening may be configured as a double keyhole having bit sides which point in dissimilar directions.
[0013] A double keyhole herein is understood to be an opening which is formed by one bore and slotted holes which adjoin thereto and which point in dissimilar directions and may be configured so as to be mutually offset. Continuing the analogy with a keyhole, the slotted holes adjoining the bore herein may be referred to as bit sides.
[0014] By configuring the opening as a double keyhole, it is achieved that the cartridge flange according to the invention may be placed in a simple manner onto a bolt which optionally is already provided with a nut, and may subsequently be twisted such that a simple potential for fastening results.
[0015] It is of advantage herein for the bit sides of the double keyhole each to have central longitudinal axes which display dissimilar spacing radii in relation to an imaginary center of the annular cartridge flange. In this way, a cartridge flange according to the invention may be used for various filter units as well as a special cartridge flange which matches only specific filter units.
[0016] The spacing radius of the centrical longitudinal axis of a first bit side in relation to an imaginary center of the annular cartridge flange herein may be in the range from 189.5 to 192.5 mm. In one preferred embodiment, the spacing radius of the first bit side may be 191 mm.
[0017] Moreover, the centrical longitudinal axis of a second bit side may preferably have a spacing radius in relation to an imaginary center of the annular cartridge flange in the range from 194.5 to 197.5 mm, in particular of 196 mm.
[0018] In one further advantageous embodiment, the at least one opening may be configured in the shape of a drop.
[0019] In this embodiment, in a manner similar to the variant which has been referred to as a double keyhole, a bolt having a nut may be introduced into the further part of the drop-shaped opening, and subsequently may first be latched by twisting and then secured by tightening the nut.
[0020] In another alternative embodiment, the opening is configured as an obliquely running slotted hole, wherein the slotted hole toward the ends thereof has dissimilar spacing radii in relation to an imaginary center of the cartridge flange. By way of such a profile, bolts having the most varied radial spacings in relation to an imaginary center of the annular cartridge flange may engage.
[0021] Alternatively, the lug of a cartridge flange according to the invention may have two openings which may have dissimilar spacing radii in relation to an imaginary center of the cartridge flange.
[0022] Furthermore, a cartridge flange according to the invention preferably has three lugs which are disposed so as to be offset by 120° on the external circumference.
[0023] Additionally, the lugs on the edges thereof may advantageously have an attachment which serves for preventing canting or jamming when a nut associated with the bolt is being tightened.
[0024] It is likewise of advantage for the flange body of the cartridge flange to have an opening through which air which has been filtered by a filter unit may flow out.
[0025] Advantageously, the flange body or the annular cartridge flange, respectively, on the lower side thereof displays a groove which additionally has annular ribs. On account thereof, an adhesive is distributed in such a manner that a form-fitting connection between the cartridge flange and the filter unit can be established. Additionally, a sealing foam may be received on a further groove which runs on either side, such that a seal on either side may be configured, thus enabling fitting of both sides of the cartridge flange having the associated filter unit in a suction-extraction system or filter system, respectively.
[0026] The cartridge flange may preferably be formed from plastics material, in particular from PA6, from light metal such as aluminum, from stainless steel and/or from steel, for example by way of an injection-molding method. Self-evidently, other manufacturing methods, such as casting methods, aluminum die-casting methods, and/or turning/milling, are also conceivable.
[0027] It goes without saying that the parameters mentioned herein relate to particularly advantageous embodiments and that further parameters which deviate from those already mentioned are likewise conceivable.
[0028] The lugs are preferably configured so as to be integral with the cartridge flange.
[0029] The annular basic shape of the cartridge flange has an annular external circumference on which the lugs may be configured or to which the lugs may be attached, respectively. The cartridge flange according to the invention is particularly suitable for fitting filter cartridges in industrial suction-extraction systems or air-filter systems.
[0030] The invention furthermore relates to a filter system, in particular an industrial suction-extraction system or an air-filter system, having receptacle means for fastening a filter cartridge and having a cartridge flange having an annular basic shape and at least one lug which is configured on the external circumference or on the external side of the cartridge flange, respectively. The lug has at least one opening for receiving one of the receptacle means which is configured as a bolt, for example. The lug herein may be configured in such a manner that bolts which have dissimilar radial spacings from an imaginary center of the annular basic shape of the cartridge flange may engage in the opening for final fastening of the cartridge flange.
[0031] Advantageous embodiments and refinements of the filter system are derived from dependent claims 2 to 18 relating to the cartridge flange, and in an analogous manner from the preceding and following descriptions of the cartridge flange.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The invention will be explained in more detail by means of the following drawing.
[0033] In the drawings:
[0034] FIG. 1 shows a schematic illustration of a plan view of that side of a cartridge flange according to the invention that faces away from the filter unit (upper side);
[0035] FIG. 2 shows a schematic illustration of a plan view of that side of a cartridge flange according to the invention that faces toward the filter unit (lower side);
[0036] FIG. 3 shows a schematic illustration of a further embodiment of a cartridge flange according to the invention;
[0037] FIG. 4 shows a schematic illustration of an alternative embodiment of a cartridge flange according to the invention; and
[0038] FIG. 5 shows a schematic illustration of a fragment of a filter system.
DETAILED DESCRIPTION OF THE INVENTION
[0039] A plan view of that side of a cartridge flange according to the invention that faces away from the filter unit is schematically illustrated in FIG. 1 , that side henceforth being referred to as the front side. The cartridge flange according to the invention has an annular, preferably a toroidal, basic shape which henceforth will be referred to as the flange body 1 , at least one lug 2 being attached to the external circumference of the latter.
[0040] The cartridge flange according to the invention has a flange body 1 which is configured in a toroidal manner and has a diameter in the range from 359 to 369 mm, in particular of 364 mm. In the example shown, three lugs 2 which are offset by 120° are located on the external side or on the external circumference, respectively, of the flange body 1 . The three lugs 2 each have one double keyhole 100 having two bit sides 3 and 4 , the latter being mutually opposite and being disposed so as to be mutually offset. Furthermore, the bit sides 3 and 4 in the present example have a radius in the range from 1.5 to 11.5 mm, in particular of 6.5 mm. Self-evidently, further radii are also conceivable. The bore 5 of the double keyhole 100 serves for receiving bolts which serve for connecting a filter which is connected to the cartridge flange to a master suction-extraction system. The bore 5 in the present exemplary embodiment has a diameter in the range from 8.5 to 14.5 mm, in particular of 11.5 mm. Self-evidently, other diameters are also conceivable. Furthermore, the lugs 2 , on the corners thereof, each have attachments which serve as spaces and prevent canting and jamming during fitting.
[0041] One of the bit sides 3 or 4 is disposed on a first circumferential diameter, and the other bit side 4 or 3 is disposed on a second circumferential diameter. The bit side having the smaller circumferential diameter, presently the bit side 4 , lies on a circumferential diameter in the range from 379 to 385 mm, in particular of 382 mm. Self-evidently, other circumferential diameters, are also conceivable. The bit side having the larger circumferential diameter, presently the bit side 3 , which lies on a circumferential diameter in the range from 389 to 395 mm, in particular of 392 mm, corresponds to third-party filter units. The bit side 3 may also be considered to be the universal bit side of the double keyhole, meaning that this bit side may correspond to arbitrary filter units. In the example shown, the bit sides 3 and 4 are connected in a centric manner to a bore 5 , thus forming the double keyhole 100 . A receptacle bolt may first be introduced through the bore 5 during fitting, whereupon the cartridge flange may be fixed by way of a rotation about a specific angular range and by means of a nut associated with the bolt.
[0042] Furthermore, the cartridge flange according to the invention in the present example has an opening 6 by way of which air which passes through and is cleaned by a filter may be guided in the direction of an exhaust-air duct. The encircling groove 8 which serves for receiving a sealing foam, so as to establish a seal between the cartridge flange, having the associated filter unit, and the installation point in a suction-extraction system or filter system, respectively, is likewise readily identifiable in FIG. 1 . This groove is also configured on the lower side of a cartridge flange according to the invention, that is to say on that side that faces the filter unit, such that the latter may be fitted regardless of the orientation thereof.
[0043] In FIG. 2 , an embodiment of a cartridge flange according to the invention is schematically illustrated from that side that faces the filter unit (from below). The cartridge flange according to the invention, on the lower side thereof, in relation to the corresponding groove 8 on the upper side, has a groove 8 ′ in which a sealing foam may be incorporated. A further encircling groove 9 has encircling annular ribs 10 by way of which the flow behavior of the adhesive is improved and which thus serve for improving the adhesion of the non-woven filter fabric on the cartridge flange.
[0044] The attachment 7 on the lugs 2 can also be clearly identified on the lower side of the cartridge flange. The further reference numerals are analogous to the reference numerals used in FIG. 1 .
[0045] A further embodiment of the cartridge flange according to the invention is schematically illustrated in FIG. 3 . In the present embodiment, the opening 200 of the lug 2 is configured in the shape of a drop. In this way, a bolt may be introduced on that side on which the drop-shaped opening has a larger radius, and by twisting the cartridge flange in the direction of that side on which the drop-shaped opening has a smaller radius may be fixed by means of a nut associated with the bolt. The further reference numerals are analogous to the reference numerals used in FIG. 1 .
[0046] FIG. 4 illustrates a further design embodiment of the cartridge flange according to the invention. In this variant, the lug 2 has two openings 300 which have dissimilar radial spacings from an imaginary center (M) of the annular shape of the cartridge flange. The further reference numerals are analogous to the reference numerals used in FIG. 1 .
[0047] FIG. 5 schematically shows a fragment of a filter system 1000 , having receptacle means 11 and 11 ′ which in the present embodiment are configured as bolts 11 and 11 ′, respectively. The bolts 11 , 11 ′ herein serve for fastening a filter cartridge having a cartridge flange according to the invention, which has an annular basic shape and at least one lug 2 which is configured on the external circumference or on the external side, respectively, to the filter system 1000 . The at least one lug 2 has an opening for receiving a bolt 11 or 11 ′, respectively. In FIG. 5 , two alternative positionings of the bolts 11 , 11 ′ in relation to an imaginary center M are illustrated. The bolt 11 has a spacing r 2 from an imaginary center M. The bolt 11 ′ has a spacing r 1 from an imaginary center M. The potential positions of the bolts 11 and 11 ′, as shown in FIG. 5 , are merely exemplary, further positions being conceivable.
[0048] For receiving a filter cartridge, a specific filter system will typically only have receptacle means or bolts, respectively, for fitting a filter cartridge, of which the radial spacings from an imaginary center of the cartridge flange are identical. The illustration of the bolt 11 ′ in FIG. 5 by way of dashed lines is intended merely for indicating the potential positioning of bolts in the case of a further filter system, and thus for indicating the universal or general use, respectively, of the cartridge flange according to the invention.
[0049] A filter cartridge having a cartridge flange according to the invention may be positioned on or fastened to, respectively, the bolt 11 or alternatively also the bolt 11 ′, for example. Final fastening of the filter cartridge having a cartridge flange according to the invention to a filter system by way of bolts is subsequently preferably performed using fastening means (not illustrated here) which may be configured as nuts, for example. It is self-evident that alternative fastening means may also be used. | The invention relates to a cartridge flange for fitting filter cartridges in filter systems, in particular industrial suction-extraction systems or air-filter systems. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a Continuation of U.S. patent application Ser. No. 13/363,505, filed Feb. 1, 2012, which claims priority to European Patent Application No. 09173428, filed on Oct. 19, 2009, entitled “Dynamic Resource Allocation for Distributed Cluster Storage Network”.
TECHNICAL FIELD
The present invention relates to storage controller systems, and in particular those implemented as a distributed cluster involving multiple nodes, and embedding a caching function, such as, for example, the IBM® SAN Volume Controller (IBM is a Registered Trademark of IBM Corporation in the United States, other countries, or both).
BACKGROUND OF THE INVENTION
The present invention centres on the interaction of two functions in this system—the forwarding layer and the cache used to provide write buffer resource—and how those functions handle I/O requests. A description of these is needed for an understanding of the invention.
The forwarding layer allows an I/O request to be received on any node in the system, and for that request to be forwarded to another node that will actually be responsible for servicing that request. In systems which can scale to include many nodes, this technique is commonly used to allow the work of the whole system to be shared among the member nodes, and to allow each of the nodes to only be concerned about a subset of the work of the whole system. This technique allows simpler algorithms to be used, and these algorithms also tend to scale to be operable in bigger systems more readily. Contrast this with algorithms that allow any node in the system to process any request, particularly where those requests need to be processed coherently with respect to other requests received on other nodes of the system.
When handling a forwarded I/O request, the forwarding node generally still remains involved in the I/O process. In particular the forwarding node is still responsible for performing the data transfer to/from the host, and sending completion status to the host, even though the forwarded-to node is the source and/or sink of that data and status, according to its handling of the I/O request. It is sometimes possible to hand-off the request entirely, so that once the request is forwarded, the forwarding node has no further responsibility towards it, and the exchange becomes one purely between the request originator and the forwarded-to node. But this feature is not always possible, because of constraints imposed by the fabric infrastructure connecting the originator hosts and the forwarding/forwarded-to nodes, and/or constraints in the adapter technology that interfaces the forwarding node with that fabric.
The process for a write command in particular requires the forwarding node to request a transfer of the data from the host into a buffer within that node, and then transmit the contents of that buffer to a further buffer within the forwarded-to node. One scheme for achieving this transfer involves the following steps (with reference to FIG. 2 ):
200 . Host transmits I/O write request to first node 202 . First (forwarding) node forwards request to second (forwarded-to) node 204 . Second node decides to process, allocates buffer in which to receive data, and sends request for data to first node 206 . First node allocates buffer, and sends request for data to host 208 . Host transmits data, and data is received in first node in buffer defined at 206 210 . First node is notified of completion of data transfer, and starts data transfer to second node in buffer defined at 204 212 . Second node is notified of data transfer completion, and resumes processing of write I/O request using received data
Note that the pre-allocation of buffers into which to receive data is an important requirement of operation in a storage network, such as one based on FibreChannel. Note also that these buffers are relatively expensive, which means they need to be explicitly assigned to an I/O request as it is processed, rather than being presumed to be available. Hence, in the sequence above, the host does not transmit the write data with the request at 200 ; instead it waits until it is asked for the data at 206 . Similarly, the forwarding node does not send the data until the forwarded-to node asks for it. This behaviour helps to prevent congestion arising in the fabric, where data is transmitted but cannot be received because of a lack of buffering at the receiver, and is an important feature that tends to distinguish how data transfers are performed within storage networks from how they are performed in conventional ones.
One consequence of the scheme above though, is that the whole I/O process involves more steps, and takes longer from start to finish, as compared to the equivalent process where the I/O is handled entirely within the first node, comprising the following steps (with reference to FIG. 3 ):
300 . Host transmits I/O write request to first node 302 . First node decides to process, allocates buffer in which to receive data, and sends request for data to host 304 . Host transmits data, and data is received in first node in buffer defined at 302 . 306 . First node is notified of completion of data transfer, and resumes processing of write I/O request using received data
The extra ready for data exchange can have a significant impact on the total processing time experience by the host, possibly as much as trebling the time it has to wait for the I/O request (as compared with the local processing case), and this can have a significant cost in terms of overall system performance.
The following sequence of steps can be used to mitigate this extra processing time (with reference to FIG. 4 ):
400 . Host transmits I/O write request to first node 402 . First node allocates buffer, and sends request for data to host 404 . Host transmits data, and data is received in first node in buffer defined at 402 406 . First (forwarding) node forwards request with data to second (forwarded-to) node 408 . Second node processes I/O request using the received data
The above sequence avoids an extra exchange of messages between first and second nodes to effect the data transfer during the I/O process, which significantly improves the situation compared to the first sequence. This more streamlined process does need some extra work to be performed before the I/O is processed, so as to honour the requirement that there is buffer space to perform the data transfer at 306 . The forwarded-to node must transfer a permission, commonly termed a ‘credit’, to the forwarding node, which permits it to transmit a certain amount of write data in the future, and the forwarding node must be in receipt of such credit, before it performs that transmission. The transmission consumes the credit, and so as the forwarded-to node executes and completes an I/O process, and buffer space becomes free again, it must create further credit and transmit it to the forwarding node in anticipation of further I/O.
The cache function within caching controllers such as the IBM SAN Volume Controller (hereinafter “SVC”) implements a non-volatile write cache, whereby it will process a write I/O by placing the request's data in non-volatile memory (most often within two nodes), and immediately completes the host I/O. At some later time, it will ‘destage’ the data, which involves sending a write command for that data to the disk which is the normal location for that data. When acknowledgement for that write command is received, the data can be removed from the non-volatile memory contents. The host perceives a much smaller response time for its I/O request than it would see if the request were sent directly to the disk, improving system performance. Non-volatile cache is suitably adapted to the provision of write buffer resource in data storage systems.
It is very common though to avoid issuing this write straight away. A number of advantages can be achieved through this. For example, if the host subsequently sends a further write I/O request for the same location, then that new write I/O request can be processed by replacing the existing data with the data from the later write. At some future time, when a destage write is performed, only the most recent revision of data need to be sent to the disk, saving on the number of disk operations that are performed.
Another important benefit is that when a host application generates a large burst of write I/O, this can be accepted into the non-volatile write cache quickly, and the burst of I/O is forwarded to the disk which might take much longer to process the entire burst. Therefore the host's burst of work is completed much more quickly than would be the case if it were required to wait for the disk, again improving system performance.
However, this scheme can cause problems if the host workload exceeds the ability of the backing disk subsystem for a long period of time. This can happen for instance where a disk subsystem suffers a failure, and enters a degraded performance mode. In this case, the cache memory space within the controller can become exhausted, and in this case write I/O processing must wait for space to be made available from the completion of a destage write. Many of these writes will actually need to wait for the slow controller to process a write I/O (because it is the slow controller that is consuming the majority of the write cache), and so it is possible for all I/O being processed to become backlogged by slow I/O processing in just one backing disk.
The solution to this problem is to limit the amount of cache memory that can be consumed by any one backing disk subsystem. When this scheme operates, I/Os do not automatically get granted buffer space when they are received. In particular, if the write I/O is destined for a disk that is judged to have already consumed its fair share of system resources, then processing of that write I/O is suspended until the share of system resources consumed by that disk and/or its ability to process I/O changes, so it is judged that it is entitled to be granted further resource. In the meantime, other I/O requests that are being processed to disk subsystems which are processing I/O acceptably and are consuming less than the amount of resource than they are entitled to are allowed to continue.
The cache function implemented within SVC is typical of those of many caching controllers, in that for any given host volume (vdisk) it can support I/O on only one or two nodes of the system. The forwarding layer is used ‘above’ the cache layer, (so that the forwarding layer processes a given host I/O before the cache layer), and so this allows all nodes in the system to receive I/O for a vdisk, and that I/O is then forwarded to one of the up to two nodes that is able to process that I/O.
Observe now what can happen when the optimised forwarding scheme above interacts with the cache partitioning algorithm described. The optimised forwarding scheme allocates relatively scarce buffering resource ahead of time, before the cache algorithm is able to judge whether the disk subsystem has consumed more than its fair share of resource. If the cache algorithm acts to delay I/O processing, it stops the I/O from consuming more cache resource, but that I/O request has already consumed buffer space within the forwarding node. This can quickly lead to the forwarding node running out of buffer space to service any I/O request.
This means that the same problem has arisen as was attempted to be solved by the cache partitioning scheme, though the exhaustion here is suffered in the forwarding buffer resource of the forwarding node, rather than the cache buffer resource of the forwarded-to node.
The slower forwarding algorithm outlined above with reference to FIG. 2 does not exhibit this problem. It waits for the cache to decide to process the I/O before committing buffer resource to the request at step 204 , and so it only allocates buffer resource to I/Os whose disk subsystem is judged to deserve more resource. But this scheme greatly increases the processing time for the I/O.
What is needed is a technique by which forwarded write I/Os can be processed with minimum response time, but without leading to problems from resource exhaustion when a subset of those I/Os is running slowly.
SUMMARY OF INVENTION
The present invention accordingly provides, in a first aspect, an apparatus operable in a distributed cluster storage network having a host computer system and a storage subsystem, comprising: a plurality of storage control nodes each operable to write data to storage responsive to a request from said host computer system; a forwarding layer at a first of said plurality of storage control nodes operable to forward data to a second of said plurality of storage control nodes; a buffer control component at each of said plurality of storage control nodes operable to allocate buffer resource for data to be written to said storage; and a communication link between said buffer control component and said forwarding layer at each of said plurality of storage control nodes operable to communicate a constrained status indicator of said buffer resource to said forwarding layer.
The apparatus may further comprise a mode selector component responsive to receiving said constrained status indicator at said forwarding layer for selecting a constrained mode of operation of a write, said constrained mode of operation requiring allocation of buffer resource at said second storage control node and communication of said allocation before said first storage control node becomes operable to allocate buffer resource for said data and to forward said data. Preferably, said communication link between said buffer control component and said forwarding layer at each of said plurality of storage control nodes is further operable to communicate an unconstrained status indicator of said buffer resource to said forwarding layer. Preferably, said mode selector component is responsive to receiving said unconstrained status indicator at said forwarding layer for selecting an unconstrained mode of operation of a write, said unconstrained mode of operation granting use of a predetermined resource credit provided by said second to said first of said storage control nodes and permitting forwarding of a write request with said data from said first to said second of said storage control nodes. Preferably, said distributed cluster storage network comprises a storage virtualization controller.
In a second aspect, there is provided a method of operating a distributed cluster storage network having a host computer system and a storage subsystem, comprising the steps of: receiving at a first of said plurality of storage control nodes a request to write data to storage from said host computer system; forwarding said data by a forwarding layer at said first of said plurality of storage control nodes to a second of said plurality of storage control nodes; allocating buffer resource for data to be written to said storage by a buffer control component at each of said plurality of storage control nodes; and communicating a constrained status indicator of said buffer resource to said forwarding layer.
The method may further comprise, responsive to receiving said constrained status indicator at said forwarding layer, selecting a constrained mode of operation of a write, said constrained mode of operation requiring allocation of buffer resource at said second storage control node and communication of said allocation before said first storage control node becomes operable to allocate buffer resource for said data and to forward said data. The method may further comprise communicating an unconstrained status indicator of said buffer resource to said forwarding layer using a communication link between said buffer control component and said forwarding layer. The method may further comprise, responsive to receiving said unconstrained status indicator at said forwarding layer, selecting an unconstrained mode of operation of a write, said unconstrained mode of operation granting use of a predetermined resource credit provided by said second to said first of said storage control nodes and permitting forwarding of a write request with said data from said first to said second of said storage control nodes. Preferably, operating said distributed cluster storage network comprises operating a storage virtualization controller.
In a third aspect, there is provided a computer program comprising computer program code to, when loaded into a computer system and executed thereon, cause said computer system to perform all the steps of a method according to the second aspect.
A preferred embodiment of the present invention thus introduces a new communication between the buffer control and forwarding layers. In essence the cache function transmits a status which indicates whether a particular set of I/Os are being processed expeditiously, or whether they are being delayed because of a backlog in the underlying subsystem. This indication is transmitted to all nodes, and is used on those nodes to control how the forwarding layer processes write requests.
Where the forwarding layer is informed the I/Os are being processed without delays, then it will use the quicker scheme, immediately allocating a buffer and requesting the data from the host, and it will forward the data along with the I/O request to minimise the extra processing time.
Where the forwarding layer is informed that I/Os are being delayed in processing, then it will forward just the request message, and only allocate a buffer when it receives the explicit request for the data, which also acts as the indication that that particular I/O process has been granted resource and merits processing.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 shows an arrangement of apparatus in accordance with a preferred embodiment of the invention;
FIGS. 2 to 4 show the steps of a method of operation according to the prior art; and
FIGS. 5 and 6 show the steps of a method of operation according to a preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In a preferred SVC embodiment, the buffer control component responsible for providing buffer resource from non-volatile cache maintains status on a per-vdisk (host volume) level which indicates whether that vdisk is running in the ‘constrained resource’ mode—so that resources are known to be depleted, or whether the vdisk is permitted to run in an ‘unconstrained resource’ mode with respect to allocating resources for new host I/O.
The SVC clustering infrastructure is used to communicate this status to the forwarding layer, on all nodes. Within each node the forwarding layer uses this status to decide between two completely separate paths for handling write I/O, where forwarding is required. (Where the node that received the host I/O is also one of the nodes on which the cache function is able to operate, then the I/O is passed to cache without any buffers being allocated by the forwarding layer at all, and the algorithm here is not required).
Turning to FIG. 1 , there is shown a system 100 comprising a host 102 operable to communicate with a pair of storage control nodes (NODE 1 , NODE 2 ) 104 , 106 to write data from host 102 to storage held in storage subsystem 108 . Storage control nodes 104 , 106 are operable to make use of buffer resources 110 , 112 to hold write data prior to destaging to storage held by storage subsystem 108 . Storage control nodes 104 , 106 further comprise forwarding layers 118 , 120 , which are operable to forward write data. Storage control nodes 104 , 106 further comprise buffer control components 114 , 116 to control the buffer resources 110 , 112 . Buffer resources 110 , 112 are from time to time subject to resource constraint. Storage control nodes 104 , 106 are provided with communication links 122 , 124 between buffer control components 114 , 116 and forwarding layers 118 , 120 to communicate indicators indicating whether one or more of buffer resources 110 , 112 is currently subject to resource constraint, or in the alternative, indicating that one or more of buffer resources 110 , 112 is not currently suffering from such resource constraint. Forwarding layers 118 , 120 are further provided with mode selectors 126 , 128 to select a mode of operation responsive to the receipt of the indicators over communication links 122 , 124 to select between a ‘constrained resource’ mode of operation and an ‘unconstrained resource’ mode of operation.
In ‘constrained resource’ mode, the flow is (with reference to FIG. 5 ):
500 . Host transmits I/O write request to first node 502 . First (forwarding) node forwards request to second (forwarded-to) node which contains the cache function able to process I/O for that vdisk 504 . Second node's cache layer decides to process, allocates buffer in which to receive data, and sends request for data to first node 506 . First node allocates buffer, and sends request for data to host 508 . Host transmits data, and data is received in first node in buffer defined at 506 510 . First node is notified of completion of data transfer, and starts data transfer to second node in buffer defined at 504 512 . Second node is notified of data transfer completion, and the cache layer resumes processing of write I/O request using received data
In ‘unconstrained resource’ mode, there is an additional setup flow before I/O is processed (with reference to FIG. 6 ):
600 . Second (forwarded-to) node allocates some buffer resource 602 . Second node transmits credits to first (forwarding) node entitling that node to transmit a defined amount of write data
Then, the following write I/O flow is performed when the I/O is actually received:
604 . Host transmits I/O write request to first node 606 . First node allocates buffer, and sends request for data to host 608 . Host transmits data, and data is received in first node in buffer defined at 606 610 . First (forwarding) node forwards request with data to second (forwarded-to) node which contains the cache function able to process I/O for that vdisk 612 . Second node is notified of receipt of I/O request and data, and cache layer processes I/O request using the received data.
On completion of the I/O request, the freed buffer resource is used to repeat the setup cycle and provide new credit to the forwarding node for future I/O.
The credit messages can most optimally be piggy-backed on other messages that flow in the same direction to minimise overhead caused by these. The resources used by the flows need to be sufficiently separate, to avoid deadlock arising from different paths allocating the same resources in different orders, as would be clear to one of ordinary skill in the art of distributed I/O systems.
It will be clear to one of ordinary skill in the art that the preferred embodiment of the present invention is industrially applicable in providing advantageous efficiencies in the operation of distributed cluster storage networks.
It will be clear to one of ordinary skill in the art that all or part of the method of the preferred embodiments of the present invention may suitably and usefully be embodied in a logic apparatus, or a plurality of logic apparatus, comprising logic elements arranged to perform the steps of the method and that such logic elements may comprise hardware components, firmware components or a combination thereof
It will be equally clear to one of skill in the art that all or part of a logic arrangement according to the preferred embodiments of the present invention may suitably be embodied in a logic apparatus comprising logic elements to perform the steps of the method, and that such logic elements may comprise components such as logic gates in, for example a programmable logic array or application-specific integrated circuit. Such a logic arrangement may further be embodied in enabling elements for temporarily or permanently establishing logic structures in such an array or circuit using, for example, a virtual hardware descriptor language, which may be stored and transmitted using fixed or transmittable carrier media.
It will be appreciated that the method and arrangement described above may also suitably be carried out fully or partially in software running on one or more processors (not shown in the figures), and that the software may be provided in the form of one or more computer program elements carried on any suitable data-carrier (also not shown in the figures) such as a magnetic or optical disk or the like. Channels for the transmission of data may likewise comprise storage media of all descriptions as well as signal-carrying media, such as wired or wireless signal-carrying media.
A method is generally conceived to be a self-consistent sequence of steps leading to a desired result. These steps require physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It is convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, parameters, items, elements, objects, symbols, characters, terms, numbers, or the like. It should be noted, however, that all of these terms and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities.
The present invention may further suitably be embodied as a computer program product for use with a computer system. Such an implementation may comprise a series of computer-readable instructions either fixed on a tangible medium, such as a computer readable medium, for example, diskette, CD-ROM, ROM, or hard disk, or transmittable to a computer system, via a modem or other interface device, over either a tangible medium, including but not limited to optical or analogue communications lines, or intangibly using wireless techniques, including but not limited to microwave, infrared or other transmission techniques. The series of computer readable instructions embodies all or part of the functionality previously described herein.
Those skilled in the art will appreciate that such computer readable instructions can be written in a number of programming languages for use with many computer architectures or operating systems. Further, such instructions may be stored using any memory technology, present or future, including but not limited to, semiconductor, magnetic, or optical, or transmitted using any communications technology, present or future, including but not limited to optical, infrared, or microwave. It is contemplated that such a computer program product may be distributed as a removable medium with accompanying printed or electronic documentation, for example, shrink-wrapped software, pre-loaded with a computer system, for example, on a system ROM or fixed disk, or distributed from a server or electronic bulletin board over a network, for example, the Internet or World Wide Web.
In one alternative, the preferred embodiment of the present invention may be realized in the form of a computer implemented method of deploying a service comprising steps of deploying computer program code operable to, when deployed into a computer infrastructure and executed thereon, cause said computer system to perform all the steps of the method.
In a further alternative, the preferred embodiment of the present invention may be realized in the form of a data carrier having functional data thereon, said functional data comprising functional computer data structures to, when loaded into a computer system and operated upon thereby, enable said computer system to perform all the steps of the method.
It will be clear to one skilled in the art that many improvements and modifications can be made to the foregoing exemplary embodiment without departing from the scope of the present invention. | An apparatus, method and computer program in a distributed cluster storage network comprises storage control nodes to write data to storage on request from a host; a forwarding layer at a first node to forward data to a second node; a buffer controller at each node to allocate buffers for data to be written; and a communication link between the buffer controller and the forwarding layer at each node to communicate a constrained or unconstrained status indicator of the buffer resource to the forwarding layer. A mode selector selects a constrained mode of operation requiring allocation of buffer resource at the second node and communication of the allocation before the first node can allocate buffers and forward data, or an unconstrained mode of operation granting use of a predetermined resource credit provided by the second to the first node and permitting forwarding of a write request with data. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of the U.S. National Stage designation of International application no. PCT/EP01/03100 Filed Mar. 20, 2001, the entire content of which is expressly incorporated herein by reference thereto.
TECHNICAL FIELD
[0002] The present invention relates to a method of producing a beta-glucan; use of a non-pathogenic saprophytic filamentous fungus or composition comprising it for providing a beta-glucan and thereby improving food structure, texture, stability or a combination thereof; use of a non-pathogenic saprophytic filamentous fungus for providing a beta-glucan and thereby providing nutrition; and use of a fungus or composition comprising it in the manufacture of a medicament or nutritional composition for the prevention or treatment of an immune disorder, tumor or microbial infection.
BACKGROUND ART
[0003] Over the last decade there has been a great deal of interest in biopolymers from microbial origins in order to replace traditional plant—and animal derived gums in nutritional compositions. New biopolymers could lead to the development of materials with novel, desirable characteristics that could be more easily produced and purified. For this reason, the characterization of exopolysaccharide (“EPS”) production at a biochemical as well as at a genetic level has been studied. An advantage of EPS is that it can be secreted by food micro-organisms during fermentation, but using EPS produced by micro-organisms gives rise to the problem that the level of production is very low (50-500 mg/l) and that once the EPS is extracted it loses its texturing properties.
[0004] One example of an EPS is a beta-glucan. Beta-glucans are made of a β-glucose which are linked by 1-3 or 1-6 bonds and have the following characteristics that are attractive to processors in the food-industry: viscosifying, emulsifying, stabilising, cryoprotectant and immune-stimulating activities.
[0005] Remarkably, it has been found that fungi can produce high amounts of biopolymers (20 g/l) such as beta-glucans. One example is scleroglucan, a polysaccharide produced by certain filamentous fungi (e.g. Sclerotinia, Corticium, and Stromatina species) which, because of its physical characteristics, has been used as a lubricant and as a pressure-compensating material in oil drilling (Wang, Y., and B. Mc Neil. 1996. Scleroglucan. Critical Reviews in Biotechnology 16: 185-215).
[0006] Scleroglucan consists of a β(1-3) linked glucose backbone with different degrees of β(1-6) glucose side groups. The presence of these side groups increases the solubility and prevents triple helix formation that, by consequence, decreases its ability to form gels. The viscosity of scleroglucan solutions shows high tolerance to pH (pH 1-11), temperature (constant between 10-90° C.) and electrolyte change (e.g. 5% NaCl, 5% CaCl 2 ). Furthermore, its applications in the food industry for bodying, suspending, coating and gelling agents have been suggested and strong immune stimulatory, anti-tumor and anti-microbial activities have been reported (Kulicke, W. M., A. I. Lettau, and H. Thielking. 1997, Correlation between immunological activity, molar mass, and molecular structure of different (1→3)-β-D-glucans. Carbohydr. Res. 297: 135-143).
[0007] As there is a need for these type materials in the food industry, they have been further investigated by the present inventors, and this invention now has identified unexpected benefits in food processing operations due to the use of these materials.
SUMMARY LF THE INVENTION
[0008] Remarkably, a class of filamentous fungi has now been identified and isolated which has been found to produce a fungal exopolysaccharide that exhibits characteristics that are attractive to the food industry. Two aspects of the EPS of interest are (a) its good texturing properties and (b) its ability to promote an immuno-stimulatory effect in in vitro and in vivo immunological assays. The fungal EPS could be incorporated into a health food (e.g., EPS as texturing fat replacer for low-calorie products or new immuno-stimulatory products) or provided alone for example as a food supplement.
[0009] Surprisingly, it has also been found that these fungi are able to produce a remarkably high yield of a beta-glucan.
[0010] Accordingly, in a first aspect the present invention provides a method of producing a beta-glucan which comprises fermenting a suspension comprising a non-pathogenic saprophytic filamentous fungus under conditions sufficient to produce a beta-glucan and extracting a beta-glucan from the fermented suspension.
[0011] In a second aspect the present invention provides a method of enhancing one or more of structure, texture, or stability of a food product which comprises providing a beta-glucan by a non-pathogenic saprophytic filamentous fungus or composition containing same, and adding the beta-glucan to the food product in an amount effective to thereby enhance food structure, texture, stability or combinations thereof.
[0012] In another aspect, the invention relates to a method of providing nutrition in a food product which comprises providing a beta-glucan by a non-pathogenic saprophytic filamentous fungus or composition containing same, and adding the beta-glucan to the food product in an amount sufficient to increase its nutrition content.
[0013] Yet another aspect of the invention relates to a method for manufacturing a medicament or nutritional composition for the prevention or treatment of an immune disorder, tumor or microbial infection which comprises providing a beta-glucan by a non-pathogenic saprophytic filamentous fungus or composition containing same, and forming a medicament or nutritional composition from a therapeutically effective amount of the beta-glucan.
[0014] In these methods of use the beta-glucan can be provided by the production methods described herein
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] One or more of a non-pathogenic saprophytic filamentous fungus selected from the group consisting of Penicillium chermesinum, Penicillium ochrochloron, Rhizoctonia sp., Phorna sp., and combinations thereof is fermented to form the beta-glucan. Preferably, at least three of these fungi are fermented together. More preferably all of these fungi are fermented together.
[0016] The fermenting step is conducted for at least about 50 hours, preferably for about 80 hours to about 120 hours, and even more preferably for about 96 hours. These times are advantageous for obtaining high yields of beta-glucan.
[0017] The fermenting step is advantageously conducted in suspension in a medium comprising at least one component selected from the group consisting of NaNO 3 , KH 2 PO 4 , MgSO 4 , KCl and yeast extract. Preferably, at least two or three of these components are used and most preferably all these components are used together to provide the best yields of beta-glucan. Advantageously, the beta-glucan is added to a food product, a nutritional composition, or a medicament.
[0018] Preferably, the fungus is cultivated in a minimal medium. More preferably, the medium consists essentially of glucose and salts, and provides the advantage of enabling isolation of a highly pure polysaccharide at the expense of the production yield. This is because yeast extract contains polysaccharides that are difficult to separate from the EPS. Most preferably, the medium comprises NaNO 3 (10 mM), KH 2 PO 4 (1.5 g/l), MgSO 4 (0.5 g/l), KCl (0.5), C 4 H 12 N 2 O 6 (10 mM) glucos (60) and has a pH of 4.7.
[0019] The suitable fungus that can be used according to the invention includes those selected from the group consisting of Penicillium chermesinum, Penicillium ochrochloron, Rhizoctonia sp., Phoma sp., or a combination thereof.
[0020] Additional features and advantages of the present invention are described in, and will be apparent from the description of the most preferred embodiments which are set out below and in the examples.
[0021] In one preferred embodiment, beta-glucans are produced by fermenting a suspension which comprises a fungus in a medium of (g/l) NaNO 3 (3), KH 2 PO 4 (1), MgSO 4 (0.5), KCl (0.5), Yeast Extract (1.0), and glucose (30) with the pH of medium adjusted to 4.7. The fermentation is allowed to proceed for about 96 hours at about 28° C. with shaking at about 18 rpm. In an alternative embodiment, strains which initially do not appear to produce the polysaccharide are incubated for about 168 hours and then are added to the medium under the previously described conditions.
EXAMPLES
[0022] The following examples are given by way of illustration only and in no way should be construed as limiting the subject matter of the present application.
Example 1
Fungal Beta-Glucan Production
[0023] The following fungal isolates were isolated and classified:
Lab-isolate “Italian”, public name CBS identification P28 Penicillium chermesinum Penicillium glabrum (teleomorph*) P45 Penicillium ochrochloron Eupenicillium euglaucum (anamorph**) P82 Rhizoctonia sp. Botryosphaeria rhodina (teleomorph)/ Lasiodiplodia theobromae (anamorph) P98 Phoma sp. N/A VT13 Phoma sp. N/A VT14 Phoma sp. N/A
Example 2
Standard Polysaccharide Production
[0024] Media TB1 (g/l) was used as follows: NaNO 3 (3), KH 2 PO 4 (1), MgSO 4 (0.5), KCl (0.5), Yeast Extract (1.0), and glucose (30) with the pH adjusted to 4.7.
[0025] The fermentation time was 96 h at 28° C. with shaking at 180 rpm. For strains which initially did not seem to produce any polysaccharide the incubation was prolonged to 168 h.
[0026] Results of polysaccharide production were as follows:
Specific Biomass Polysaccharide production Fungal strain (g/l) (g/l) pH (g/g) Slerotium glucanicum NRRL 3006 9.06 ± 2.06 11.20 ± 0.71 3.79 1.24 Botritis cinerea P3 2.64 ± 0.10 5.90 ± 0.57 4.35 2.23 Sclerotinia sclerotiorum P4 1.16 ± 0.16 1.61 ± 0.13 2.50 1.38 Fusarium culmorum P8 6.51 ± 1.05 0.82 ± 0.13 7.70 0.13 Not identified P9 5.43 ± 0.53 1.32 ± 0.02 4.00 0.24 Penicillium chermesinum P28 4.08 ± 1.17 0.68 ± 0.11 3.30 0.17 Penicillium ochrochloron P45 10.53 ± 2.87 0.45 ± 0.07 3.50 0.04 Fusarium sp. P58 8.60 ± 2.12 1.25 ± 0.35 7.44 0.15 Sclerotinia sclerotiorum P62 2.10 ± 0.00 0.86 ± 0.00 3.80 0.41 Sclerotinia sclerotiorum P63 4.08 ± 0.54 1.33 ± 0.04 3.30 0.33 Botritis fabae P65 19.70 ± 0.00 0.50 ± 0.00 4.94 0.03 Rhizoctonia fragariae P70 12.52 ± 0.40 1.55 ± 0.07 8.60 0.12 Colletotrichum acutatum P72 6.01 ± 0.89 1.05 ± 0.07 7.00 0.17 Pestalotia sp. P75 8.70 ± 0.28 1.90 ± 0.28 6.30 0.22 Colletotrichum sp. P80 12.00 ± 1.95 0.65 ± 0.07 6.50 0.05 Colletotrichum sp. P81 5.10 ± 0.71 0.80 ± 0.00 5.70 0.16 Rhizoctonia sp. P82 5.70 ± 0.28 8.90 ± 1.56 6.50 1.56 Acremonium sp. P83 4.69 ± 0.62 1.45 ± 0.07 7.20 0.31 Acremonium sp. P84 5.50 ± 0.00 1.30 ± 0.00 7.20 0.24 Acremonium sp. P86 3.90 ± 0.71 1.00 ± 0.14 5.85 0.26 Acremonium sp. P90 8.08 ± 0.01 0.73 ± 0.18 4.40 0.09 Not identified P91 10.50 ± 0.14 1.28 ± 0.31 6.83 0.12 Chaetomium sp. P94 8.30 ± 1.43 1.00 ± 0.28 7.40 0.12 Phoma herbarum P97 13.61 ± 2.34 0.98 ± 0.22 7.50 0.07 Phoma sp. P98 11.01 ± 1.07 2.89 ± 0.01 8.00 0.26 Phoma sp. P99 11.76 ± 1.66 0.66 ± 0.04 6.45 0.06
Example 3
Optimized Polysaccharde Production
[0027] Polysaccharide production by Rhizoctonia sp. P82, Phoma sp. P98 and Penicillium chermesinum P28 were studied. The results were as follows:
[0028] A. Effect of carbon source cultivated on TB1:
I. EPS production by Rhizoctonia sp. P82 Carbon Biomass Polysaccharide Specific production source** (g/l) (g/l) pH (g/g) Glucose 3.74 ± 0.80 18.55 ± 0.57 5.48 4.96 Fructose 4.20 ± 0.58 21.10 ± 0.89 5.60 5.02 Galactose 4.21 ± 0.19 16.67 ± 1.20 6.52 3.96 Xylose 3.45 ± 0.53 15.94 ± 2.42 6.07 4.63 Sorbitol 5.19 ± 0.80 4.70 ± 0.21 6.16 0.91 Glycerol 5.25 ± 0.60 1.54 ± 0.42 6.15 0.29 Sucrose 4.03 ± 0.59 14.07 ± 0.64 5.61 3.49 Maltose 4.07 ± 0.32 12.22 ± 0.34 5.28 3.00 Lactose 4.63 ± 0.47 8.78 ± 0.59 6.34 1.90 Starch 5.77 ± 0.95 17.36 ± 0.69 6.26 3.01
[0029] [0029] II. EPS production by Phoma sp. P98. Carbon Biomass Polysaccharide Specific production source** (g/l) (g/l) PH (g/g) Glucose 11.99 ± 0.64 1.97 ± 1.22 7.31 0.16 Fructose 11.11 ± 0.76 1.22 ± 0.45 7.35 0.11 Galactose 10.35 ± 0.78 4.12 ± 0.03 7.44 0.40 Xylose 11.47 ± 1.40 2.57 ± 0.27 7.35 0.22 Sorbitol 11.17 ± 0.69 7.54 ± 1.10 7.10 0.68 Glycerol 11.00 ± 0.37 0.63 ± 0.05 7.29 0.06 Sucrose 12.93 ± 0.44 2.91 ± 0.55 7.36 0.23 Maltose 12.50 ± 0.18 2.65 ± 0.98 6.92 0.21 Lactose 9.77 ± 0.01 1.06 ± 0.14 7.05 0.11 Starch 13.51 ± 1.65 2.28 ± 0.11 7.43 0.17
[0030] [0030] III. EPS production by Penicillium chermesinum P28*. Carbon Biomass Polysaccharide Specific production source** (g/l) (g/l) PH (g/g) Glucose 11.69 ± 0.04 0.59 ± 0.13 3.51 0.05 Fructose 12.91 ± 1.20 0.46 ± 0.06 3:64 0.04 Galactose 8.64 ± 2.09 0.00 ± 0.00 5.23 0.00 Xylose 10.68 ± 0.06 0.41 ± 0.13 3.57 0.04 Sorbitol 8.58 ± 1.67 1.09 ± 0.01 5.07 0.13 Glycerol 13.06 ± 1.05 0.18 ± 0.04 3.57 0.01 Sucrose 13.11 ± 0.80 0.59 ± 0.11 3.44 0.05 Maltose 10.90 ± 1.11 0.61 ± 0.16 3.53 0.06 Lactose 9.38 ± 0.34 0.00 ± 0.00 4.69 0.00 Starch 9.92 ± 2.04 0.50 ± 0.05 3.58 0.05
[0031] B. Effect of glucose concentration cultivated on TB 1:
I. EPS production by Rhizoctonia sp. P82*. Glucose Biomass Polysaccharide Specific production (g/l) (g/l) (g/l) pH (g/g) 30 3.74 ± 0.80 18.55 ± 0.57 5.85 4.96 40 7.29 ± 0.42 21.40 ± 0.89 6.03 2.94 50 8.30 ± 0.74 30.20 ± 1.47 5.67 3.64 60 8.17 ± 1.34 35.26 ± 1.64 6.13 4.32
[0032] [0032] II. EPS production by Phoma sp. P98*. Sorbitol Biomass Polysaccharide Specific production (g/l) (g/l) (g/l) pH (g/g) 30 8.60 ± 0.88 5.78 ± 0.61 7.22 0.67 40 12.08 ± 0.71 8.76 ± 0.40 7.12 0.73 50 13.22 ± 1.43 10.70 ± 0.48 7.13 0.81 60 16.47 ± 0.21 13.11 ± 0.33 7.56 0.80
[0033] Surprisingly, it can be seen from the results that increasing the concentration of the carbon source (glucose and sorbitol for Rhizoctonia sp. P82 and Phonza sp. P98, respectively), EPS production by both strains increased markedly (approx. 100% increase) reaching a maximum of 35.2 and 13.1 g/l, respectively.
[0034] C. Effect of nitrogen source cultivated on TB 1:
I. EPS production by Rhizoctonia sp. P82.* Nitrogen Biomass Polysaccharide Specific production source (g/l) (g/l) PH (g/g) NaNO 3 3.74 ± 0.80 18.55 ± 0.57 5.53 4.96 NH 4 NO 3 4.05 ± 0.29 13.07 ± 1.87 2.58 3.23 Urea 5.54 ± 0.35 21.20 ± 0.14 5.43 3.82 (NH 4 ) 2 HPO 4 3.09 ± 0.81 14.26 ± 0.52 2.44 4.61 (NH 4 ) 2 SO 4 2.39 ± 0.49 8.91 ± 0.58 2.23 3.73
[0035] [0035] II. EPS production by Phoma sp. P98* Nitrogen Biomass Polysaccharide Specific production source (g/l) (g/l) PH (g/g) NaNO 3 11.46 ± 0.85 3.24 ± 0.63 7.22 0.28 NH 4 NO 3 6.12 ± 0.33 1.17 ± 0.43 2.33 0.19 Urea 8.09 ± 1.01 3.57 ± 0.97 6.18 0.44 (NH 4 ) 2 HPO 4 6.53 ± 0.44 0.00 ± 0.00 2.43 0.00
[0036] Besides sodium nitrate, other nitrogen sources such as urea, ammonium nitrate, ammonium phosphate and ammonium sulphate were used. Remarkably, on urea, EPS production by Rhizoctonia sp. P82 and Phoma sp. P98 reached the same levels obtained on sodium nitrate.
Example 4
EPS Purification and Characterization
[0037] The EPSs produced by Rhizoctonia sp. P82, Phoma sp. P98 and Penicillium chermesinum P28 were purified. The polysaccharides were exclusively constituted of sugars, thus indicating suprisingly high levels of purity. Both thin layer chromatography (TLC) and gas chromatography (GC) analysis showed that the EPSs from Rhizoctonia sp. P82 and Phoma sp. P98 were constituted of glucose only. In contrast, that from P. chermesinum P28 was constituted of galactose with traces of glucose.
[0038] The molecular weights (MW) of the EPSs from Rhizoctonia sp. and Phoma sp., estimated by gel permeation chromatography using a 100×1 cm Sepharose CL4B gel (Sigma) column, were both approximately 2·10 6 Da.
[0039] Determination of the position of the glucosidic linkages in the EPSs from Rhizoctonia sp. P82 and Phoma sp. P98 was carried out by GCms and GC after methylation, total hydrolysis, reduction and acetylation. The main products were identified by GCms analysis as glucitol 2,4-di-O-methyl-tetracetylated, glucitol 2,4,6-tri-O-methyl-triacetylated and glucitol 2,3,4,6-tetra-O-methyl-diacetylated indicating that both EPSs were characterised by monosaccharides linked with β-1,3 and β-1,6 linkages. In the case of the EPS from Phoma sp., the GC analyses showed three peaks in a quantitative ratio typical of a glucan with many branches; besides the above reaction products, the same type of analysis showed that the EPS from Rhizoctonia sp. gave rise to other reaction products such as penta- and esa-O-methyl-acetylated compounds which clearly indicated an uncompleted methylation.
[0040] Surprisingly, NMR analysis confirmed that both polysaccharides were pure, constituted of glucose only and characterized by β-1,3 and β-1,6 linkages.
Example 5
EPS Immuno-Stimulatory Effects
[0041] The EPSs from Rhizoctonia sp. P82 and Phoma sp. P98 were subjected to in vitro and in vivo experiments. A purified scleroglucan, obtained from S. glucanicum NRRL 3006, was used as a control. The purified EPSs were randomly broken in fragments of different molecular weights (from 1·10 6 to 1·10 4 Da) by sonication. The free glucose concentrations of the sonicated samples did not increase, thus indicating that no branches were broken. The experiments were carried out with EPSs at high MW (HMW, the native EPSs), medium MW (MMW, around 5·10 5 Da) and low MW (LMW, around 5·10 4 Da).
[0042] Immuno-stimulatory action was evaluated in vitro by determining effect on TNF-α production, phagocytosis induction, lymphocytes proliferation and IL-2 production.
[0043] All the EPSs stimulated monocytes to produce TNF-a factor; its content increased with increased polysaccharide concentration and was maximum when medium and low MWs were used.
[0044] In order to assess the effect of the EPSs on phagocytosis, two methods (Phagotest and Microfluoimetric Phagocytosis Assay) were used. The results gave a good indication that a high concentration of EPS improves phagocytosis.
[0045] In contrast, no significant effects were observed on lymphocyte proliferation and IL-2 production when the EPSs were added either alone or in combination with phytohemagglutinin (PHA). In addition, no cytotoxic effects were observed.
[0046] An in vivo study was carried out to assess immuno-stimulatory activity of the EPS using MMW (around 5·10 5 Da) glucan from Rhizoctonia sp. P82.
[0047] Female mice were inoculated three times subcutaneously (SC) and/or orally (OR) with MMW EPS (2 mg/100 g weight) and Lactobacillus acidophilus (1·10 8 cells/100 g weight) after 1, 8 and 28 days. Bleedings were carried out after 13 and 33 days. In vivo immuno-stimulation was evaluated by comparing antibody production by an ELISA test.
[0048] All the mice that received OR bacteria (groups 3, 4 and 5) showed no increase in their antibody content, regardless of their glucan inoculation. However, differences in antibody production were observed among mice inoculated SC with bacteria. Furthermore, antibody levels of mice that received SC only bacteria were significantly higher (P<0.01, by Tukey Test) than those that had received glucan and bacteria both SC and glucan OR and bacteria SC.
[0049] Interestingly, the results indicate that the EPS from Rhizoctonia sp. Gives rise to a decrease in antibody concentration. Remarkably, it can be concluded from this that the glucan from Rhizoctonia sp. causes activation of an antimicrobial activity of monocytes (see the effects described above relating to TNF-α production and phagocytosis induction) with a consequent reduction in the bacterial number leading, in turn, to a consistent reduction in antibody production.
[0050] In conclusion, the three filamentous fungi Rhizoctonia sp. P82, Phoma sp. P98 and Penicillium chermesinum P28 have a surprisingly good ability to produce extracellular polysaccharides of potential interest. In particular, Rhizoctonia sp. P82 is interesting in view of its short time required for fermentation, its high level of EPS production and its absence of β-glucanase activity during the EPS production phase. Furthermore, its EPS, as well as that from Phoma sp. P98, is a glucan characterised by β-1,3 and β-1,6 linkages. In addition, results relating to immuno-stimulatory effects of the glucan produced by Rhizoctonia sp. P82 indicate the possibility of a good stimulatory activity.
[0051] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be covered by the appended claims. | A method for producing a beta-glucan from a non-pathogenic saprophytic filamentous fungus or composition that contains it. Also, methods for providing this beta-glucan in a food product to improve structure, texture, stability or combinations thereof, in a food product to provide nutrition or in the manufacture of a medicament or nutritional composition for the prevention or treatment of an immune disorder, tumor or microbial infection. | 2 |
OF INVENTION
(a) Field of the Invention
The present invention concerns a process and an apparatus for the liquefaction of a flow of gaseous oxygen under pressure. It is more particularly adapted to the storage in liquid form of an excess of gaseous oxygen from a network for the distribution of oxygen under pressure with variable load or for the production of a liquefaction unit adjacent an existing unit for air distillation initially designed to produce oxygen only under gaseous form.
(b) Description of Prior Art
There are a certain number of situations where a distribution network or an air distillation unit happens to produce oxygen in excess and it is not possible or desirable to correspondingly reduce the flow of gaseous oxygen produced. This is particularly the case of an oxygen distribution network in which the load varies so fast that it is not of interest to adapt the flow of air treated by the distillation apparatus since the frequency of change in the operating conditions would lead to losses of argon and/or energy.
SUMMARY OF INVENTION
The present invention aims at providing a process and an apparatus for the liquefaction of an excess of available gaseous oxygen which requires only a reduced quantity of liquid nitrogen to carry out this liquefaction.
According to the process of the invention, gaseous oxygen is passed through a first line which extends across a heat exchanger, liquid nitrogen is pumped into a container and liquid nitrogen is passed under pressure through a second line which extends across the exchanger, at least a portion of the nitrogen which has been vaporized and warmed up at a first temperature is withdrawn from the first line of the exchanger, the nitrogen thus withdrawn is expanded in a first turbine, the nitrogen expanded in the first turbine is recirculated through a third line extending across the exchanger and liquid oxygen which exits from the first line is stored in a container.
The apparatus for liquefaction according to the invention comprises an exchanger having a hot end and a cold end and including a first and a second crossing lines, means to connect the hot end of the first line to the oxygen distribution network, means to connect the cold line to a liquid oxygen storage container, a container for liquid nitrogen, a circuit portion including a pump and connecting the liquid nitrogen container to the cold end of the second line, a first nitrogen circuit, including a first turbine, starting from an intermediate point of the second line and reaching, at one point near the cold end of the exchanger, a third line extending across the exchanger to the hot end.
BRIEF DESCRIPTION OF DRAWINGS
Some embodiments of the invention will now be described with respect to the annexed drawings, in which:
FIG. 1 is a schematic representation of a first embodiment of an apparatus according to the invention;
FIG. 2 is a heat exchange diagram concerning this apparatus; and
FIGS. 3, 4 and 5 are views similar to FIG. 1 corresponding to three other embodiments of an apparatus according to the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
The apparatus illustrated in FIG. 1 is intended to liquefy a flow of gaseous oxygen under pressure which is conveyed by a duct 1 and originates from a source S of gaseous oxygen, for example, an air distillation unit. The apparatus essentially comprises a heat exchanger 2 of the counter-current type, an expansion turbine 3, a liquid nitrogen storage container 4 and a liquid oxygen storage container 5, these two containers being substantially at atmospheric pressure.
The exchanger 2 includes a hot end 6, substantially at room temperature and a cold end 7. The exchanger comprises a first line 8 for cooling oxygen which extends from the hot end to the cold end, a second line 9 for warming up high pressure nitrogen, extending from the cold end to the hot end, and a third line 10 for warming up low pressure nitrogen extending from an intermediate point of the exchanger near the cold end, corresponding to temperature T 1 , to the hot end.
The inlet of line 8 is connected to duct 1 and its outlet is connected to container 5 by means of a duct 13 provided with an expansion valve 14. The bottom of the container 4 is connected to the cold end of line 9 by means of a duct 15 provided with a pump 16, the outlet, at the hot end of line 9 being connected to a duct 7 for withdrawing or utilizing gaseous nitrogen, which is provided with valve 18.
The inlet of turbine 3 is connected by means of a duct 19 to line 9, at an intermediate point of the latter corresponding to an intermediate temperature T 2 higher than T 1 , and its outlet is connected to the input of line 10 by means of a duct 21.
The oxygen from duct 1, presumed at room temperature and a pressure substantially constant of about 12 bar, is cooled, liquefied then sub-cooled in line 8, the liquid which is conveyed by the recovering duct 13, after expansion in a valve 14 at a pressure slightly higher than 1 bar, is collected in container 5.
To ensure the cooling of oxygen, liquid nitrogen is pumped at about 11 bar by means of pump 16, the flow of liquid nitrogen being adjusted as a function of the flow of oxygen to be liquified. Liquid nitrogen is vaporized and warmed up in line 9. At temperature T 2 , of the order of -135° C., at least a portion of the high pressure nitrogen is bypassed in duct 19, expanded at a pressure of the order of 1 bar in turbine 3, reintroduced into line 10 at temperature T 1 , of the order of -195° C., and warmed up again up to room temperature in line 10 to be withdrawn via duct 21.
There is thus produced an additional cold input in a range of temperatures higher than T 1 . If the entire high pressure nitrogen is turbined in turbine 3, the heat exchange diagram represented in FIG. 2 is obtained where temperature T is shown in abscissae and the quantities of heat Q effectively exchanged by the fluid being warmed up (nitrogen) and by the fluid being cooled (oxygen) is shown in oridnates. Thus, curve C 1 corresponds to the cooling of oxygen and curve C 2 which should always remain above the previous one, corresponds to the warming up of high pressure and low pressure nitrogen.
As shown in FIG. 2, the warming curve for nitrogen, from T 1 to T 2 , before and after the liquefaction plateau, shows an increasing slope, and this appears in a temperature zone which borders the liquefaction temperature TL of oxygen. It will be seen that because of the turbine 3, and in view of the expansion rate of the latter, nitrogen can be vaporized at a temperature higher than the -170° C., corresponding to the above pressure of about 11 bar, to thereafter give a much closer heat exchange diagram in its cold portion than in the case where no turbine would be used. As a matter of fact, in this case, in order that curve C' 2 be located above curve C 1 , nitrogen should be vaporized under a much lower pressure, as indicated in mixed line in FIG. 2.
For example it will be observed that if a portion of the vaporized nitrogen is not treated in a turbine, the apparatus enables to produce, in duct 7, gaseous nitrogen under pressure without using compression energy.
In the embodiment of FIG. 3, turbine 3 expands nitrogen only at a mean pressure, and the mean pressure nitrogen is, at least partially, expanded in a second turbine 24 to about atmospheric pressure, then warmed up in line 25 extending from an intermediate point of the exchanger to the cold end of the latter which is connected to an exhaust duct 26.
While in the embodiment of FIG. 3, the inlet temperature of the high pressure turbine 3 is lower than that of the low pressure turbine 24, the reverse is obtained in the embodiment of FIG. 4. This variant brings about certain advantages on a thermodynamic aspect, as described in French Patent application FR 89.12517 in the name of the Applicant, the content of which is incorporated herein by reference.
In the embodiment of FIG. 5, the two turbines are not in series but in parallel: with respect to the embodiment of FIG. 1, a second turbine 24A has been added here, which is connected between line 9 and line 10 at intermediate points of the latter corresponding to temperature ranges higher than temperature T 1 and T 2 , respectively.
For a given pressure used for pumping liquid nitrogen, the process according to the invention enables to produce some variation of the pressure of oxygen that is liquefied. This pressure is limited in the lower range by the necessity to always maintain curve C 1 (FIG. 2) below curve C 2 and, toward the upper range, by economical considerations, for example, because of the differentiation of the heat exchange diagram in the cold portion thereof. By way of numerical example, with a substantially constant pressure of liquid nitrogen of 11 bar, it is possible to accept in line 8 a pressure of oxygen which varies between about 12 and 30 bar.
As a variant, if the pressure of oxygen varies beyond the above mentioned range, it is also possible to ensure that the pumping pressure for liquid nitrogen be adjusted as a function of the pressure of oxygen, at least outside this range, so as to maintain a heat exchange diagram similar to that represented in FIG. 2.
When the pressure of oxygen in duct 1 varies substantially, it may be advantageous, as represented in mixed line of FIG. 1, to ensure a slight overpressure in storage container 5, to provide a bypass 22 connecting a point of the cold part of line 8 to duct 13, upstream of the valve 14, which bypass is provided with a valve 23 governed by the temperature of oxygen at the inlet of valve 14.
According to another variation, the pressure of oxygen which is introduced into line 8 may be made constant by providing the connecting duct of this line 8 to duct 1 with an expansion valve (not illustrated).
In all cases, if the pumping pressure of nitrogen should exceed the permissible rate of expansion for a turbine, an apparatus provided with two turbines mounted in series can be used, such as those represented in FIGS. 3 or 4. | Gaseous oxygen to be cooled passes through an exchanger which is cooled with compressed liquid nitrogen, at least a portion of the vaporized nitrogen which is warmed up in the exchanger being treated in a turbine and thereafter reintroduced into the exchanger. Application for example to the storage in liquid form of excess oxygen under pressure conveyed by a distribution network with variable load. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a National Phase Application (35 USC 371) of PCT/EP2003/012409 and claims priority of German Application No. 102 57 532.0 filed Dec. 10, 2002.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a marking device for encoding metallic workpieces with two-dimensional matrix codes in which the information is present in the form of recessed embossed dots in a square or rectangular arrangement. The presence or lack of these embossed dots at the respective grid points represents the binary encoded information.
2. The Prior Art
To read back the information without error, the precision in placing the embossed dots is of high importance. The precise shape, size and depth of the dots are critical quality features. This is directly connected to the type of reading technology for such embossed or punched encodings, respectively, by means of CCD cameras. Illumination from the top or the side must create a contrast between light and dark from the respective recess by means of corresponding reflections, which is much more difficult than with printed black and white surfaces located on one level, for which the code was originally developed. A deviating shape or size of the individual recesses can easily cause (or undesirably not cause) a reflection which can lead to an undesired distortion of information. In the aerospace industry, requirements are even stricter for critical components under high load; these requirements aim at avoiding the reduction of mechanical stability due to the “notch effect”.
In order to achieve the required precision, the striking tool, normally embodied as a hard metal needle, must strike the metallic workpiece, on the one hand, very rapidly, but on the other hand, with precisely defined and reproducible energy. Many conditions must be taken into account as counteracting the desired precision. In case of an electric drive, for instance, the temperature of the copper coil of the electromagnet can increase during operation, reducing current flow and thus the power consumption of the electromagnet. During longer standstill periods of the marking device, the striking tool which is formed as a magnet keeper, or connected to or operatively connected with a magnet keeper, sticks so that the impact energy at the first dot is reduced. In principle, a striking movement which is too slow causes an oval distortion of the recess when the impact unit moves on during encoding. On the other hand, an impact speed which is too fast leads to a great variation in impact depth, since even minimum differences, e.g. due to overlaid mechanical oscillations in the striking mechanism, lead to slightly different energy outputs of the impact system during the formation of the recess. Furthermore, the material properties of the workpiece also influence the formation of the recess. Finally, mechanical tolerances also lead to errors, if they cause the movement of the magnet keeper to exceed the magnetically substantially linear range.
In known arrangements, the current is only intended to be switched on and off for the electromagnet. Clamping diodes or other overvoltage protection equipment are used for protection against overvoltage, when the electromagnet is switched off, as an inductive load. Bias resistors before the electromagnet for inducing a faster rise or drop of current in the magnet coil by increasing the time constant are also known. In these simple systems, in addition to one-time dimensioning, only the time of disconnecting can be varied after the current is switched on, whereas the entire time course of the working movement results exclusively from dimensioning and the prevailing boundary conditions. With such systems, the required precision cannot be attained.
In controlling solenoid valves, on the one hand, it is well-known to switch back to a lower holding current after the high turn-on current, which is first required for a fast movement. This switchover, however, does not take place until after switching of the valve, i.e. after the movement of the valve member, and is intended first to save energy and secondly to reduce heating of the solenoid valve.
SUMMARY OF THE INVENTION
The invention has as an object the improving of the movement of a striking tool driven by an electromagnet arrangement such that markings in the form of recesses can be formed with substantially higher precision.
Accordingly, the present invention provides a marking device for encoding a metallic workpiece with a two-dimensional matrix code which includes a striking tool; an electromagnetic device for driving the striking tool, with a working movement, to form the two-dimensional matrix code, as plural indentations, in the metallic workpiece; a return device for generating a force in opposition to the working movement; and a positioning device, displaceable in two dimensions within a plane perpendicular to the direction of the working movement, for positioning the striking tool in a desired encoding position. The marking device of the present invention further includes an electronic control unit for controlling the working movement of the striking tool, said electronic control unit setting a first current I 1 for the electromagnetic device during a first, acceleration phase of the working movement and setting a second current I 2 , lower than the first current, during a second, moving phase of the working movement, the second, moving phase extending from the first, acceleration phase until impingement of the striking tool on the metallic workpiece.
Advantageously, according to the invention, the current flow through the electromagnet can be set differently for the acceleration phase and the subsequent moving phase of the striking tool. On the one hand, this results in a fast acceleration, with the striking tool being moved against the workpiece in a defined manner after switchover to the lower current. This results in high regularity and reproducibility of the recess formed. Due to the substantially uniform movement because of the fact that the current is lower during the moving phase, a larger tolerance for the marking device's distance to the workpiece is permissible. With the known devices, a distance which becomes larger causes a deeper recess due to the longer acceleration phase. Also, because the current is lower during the moving phase, an uncontrollable, merely ballistic phase of “free flight” of the striking tool until it impinges on the workpiece surface is avoided, which would otherwise occur if the current were switched off before the tool impinges the workpiece; which, in turn, would be associated with larger tolerances of the markings.
In a simple embodiment, current switchover from the higher to the lower value in one or more steps, or continuously, takes place by means of a time control. Alternatively, this switchover can also take place in dependence on the position, with a position measuring device for controlling switchover being provided in at least one preset position. In the simplest case, this position measuring device can be a simple position sensor in a specific position or an end position sensor which responds after a certain distance traveled during the striking movement.
Advantageously, position measurement can also be employed to measure the length of the entire moving distance of the striking tool, i.e. for measuring the distance to the workpiece. The corresponding measured value can then also be used as a working parameter for defining the current intensities and times or positions, respectively.
For switching off the current exactly after the striking tool has impinged on the workpiece, preferably means for switching off the current when the impinging position is reached can be provided. In a particularly simple manner, the current increase of the supply current for the electromagnet arrangement can be detected with a current sensor, with this current increase taking place when the movement of the magnet keeper, i.e. the striking tool, has been stopped and there is no longer any change in inductivity in the coil of the electromagnet.
After the striking tool has impinged on the workpiece, the current is switched off so that the striking tool is returned to the rest position by the force of the reset device, such as e.g. a spring. Now, for avoiding rebound or need for absorption of the kinetic energy of the striking tool upon return to the rest position by absorption and/or rebounding, advantageously braking means for creating a brake current before the rest position is reached during the return motion of the striking tool can be provided. These means can be controlled in dependence on the time and/or the position, and the current value is selected such that the striking tool is braked, preferably, to a zero speed when the rest position is reached. In this manner, a very fast working cycle can be ensured.
The control equipment advantageously contains a microcomputer with a storage unit in which the working parameters are stored, especially current intensities, times, distance parameters, workpiece properties, temperatures, and the like. The working parameters are suitably contained in the form of tables and can be selected and/or altered in dependence on the respective marking process. Whereas some parameters have to be entered which take into account, e.g., the workpiece properties of the workpiece to be marked, other parameters, such as the temperature, can be detected by sensors, and again others are measured in the manner already indicated, e.g. the position of the striking tool along the entire distance of movement.
Advantageously, the control equipment in the form of a separate module is interposed between a main controller for the marking device and the electromagnet and can be retrofitted.
The various current values can be controlled in open-loop or closed-loop control, dependent on position or time, over the entire moving distance.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention are shown in the figures and explained in detail in the subsequent description.
FIG. 1 is a schematic view of the marking device for encoding metallic workpieces with two-dimensional matrix codes,
FIG. 2 is a schematic view of a first embodiment with a position-dependent control for the driving movement of the striking tool, and
FIG. 3 is a schematic diagram of a second embodiment with time-dependent control for the driving movement of the striking tool.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The marking head 10 which is schematically shown in a pictorial schematic in FIG. 1 is equipped with an electromagnet coil 11 adapted for generating the striking movement of a striking tool 12 which, in this embodiment, is exemplified by a hard metal needle. The striking tool 12 is connected to a magnet keeper 9 which can be moved towards a workpiece 14 against the force of a return spring. Of course, a different well-known return device can also be envisaged, e.g. a return device with pneumatic, hydraulic or electromagnetic action.
The marking head 10 is adjustable, by means of a positioning device (not shown), in the x- and y-directions of a plane arranged in parallel with the plane of the workpiece 14 . In this manner, the marking head 10 can reach any position of the workpiece 14 . The marking head 10 is used to emboss coding dots in the form of recesses (indentations) in the metallic workpiece 14 . These coding dots form a two-dimensional matrix code representing binary encoded information. After the desired grid point has been reached, the striking tool 12 is moved against the workpiece 14 to create the desired code indentation.
Basic control of the marking head 10 is performed by a main controller 15 which controls the position of the marking head 10 , by means of the positioning device (not shown), and the triggering of the movement of the striking tool 12 .
Between the main controller 15 and the electromagnet coil 11 , a control unit 16 is interposed by means of which the exact movement of the striking tool 12 is controlled. A first embodiment of this control unit 16 is shown in FIG. 2 and a second embodiment in FIG. 3 . In the embodiment shown in FIG. 2 , a current control stage 17 , which can be triggered from the main controller 15 , controls the electromagnet coil 11 of the marking head 10 via an amplifier unit 18 . The position signal S of a position detecting device 20 is fed into a position presetting stage 19 for detecting the current position of the striking tool 12 . This position detecting device is e.g. an inductive path-measuring system which is arranged outside the electromagnet coil 11 in FIG. 1 but which can also be integral with the magnet drive. In the position presetting stage 19 , this position signal S is compared during the striking movement with a stored switchover value S 0 , and if the same is reached, a switchover is made from an initially high current value I 1 to a lower current value I 2 . The initially high current value I 1 is used for fast acceleration of the striking tool 12 during an acceleration phase, wherein the lower current value I 2 is selected such that after this acceleration phase, the striking tool can be guided to the workpiece with as uniform a speed as possible. Naturally, the return to the lower current value I 2 can also take place in several steps. When the striking tool 12 impinges on the workpiece 14 , the supply current for the electromagnet coil 11 rises, since when the movement of the magnet keeper 9 is finished, no change in inductivity in the electromagnet coil 11 any longer takes place. This rise in current is detected by a current sensor 21 and fed into an evaluation stage 22 for the rise in current, which evaluation stage 22 can contain e.g. a differentiation stage. When this rise in current is detected, the current for the electromagnet coil 11 is switched off by means of a reset signal R.
After the current has been switched off, the striking tool 12 and the magnet keeper 9 , are moved back into the rest position shown in FIG. 1 by the force of the return spring 13 . If during the return motion, a position S 1 is detected before the rest position is reached, the current is switched on again by means of the current control stage 17 and then serves as a braking current. During this process, the position S 1 and the current intensity are selected such that the striking tool 12 is braked to a speed which is as close to zero as possible when the rest position is reached. For this purpose, either one of the currents I 1 or I 2 or a different current value can be set.
In a storage unit 23 , the working parameters for setting the positions and currents are stored. Such working parameters are e.g. current intensities, times, distance parameters, workpiece properties, temperatures and the like are stored in the form of tables. By means of these tables, the current intensities I 1 and I 2 as well as the positions S 0 and S 1 are then preset, e.g. calculated. These are parameters influencing the movement of the striking tool 12 . For instance, the temperature of the marking head 10 or the electromagnet coil 11 , respectively, can be measured in a manner which is not described in detail. Other working parameters, such as the material properties of the workpiece 14 , can be stored by means of an input device which is not shown. Another important parameter is the working stroke, i.e. the distance of the working movement until the tool impinges the workpiece 14 . By means of a measuring movement of the striking tool 12 , which takes place before the actual marking process, the distance can be measured by the position detecting device 20 . The measurement takes place until the tool impinges on the workpiece 14 which is signaled by the evaluation stage 22 .
Based on this measured value, the control parameters to be currently used for the respective workpieces 14 are then respectively altered, individually, in such a way that the striking energy effective for marking again corresponds to the desired value.
In another embodiment, this distance measurement can be applied to the position of the workpiece surface to be marked in relation to the assembly height of the marking head 10 . To this purpose, the height of the marking head 10 is set adjustably on a third NC axis. Now the striking tool 12 is completely extended with a current set by the current control stage 17 , sufficient to overcome the restoring force, and then the marking head 10 is driven against the workpiece surface from a known higher position. As soon as the striking tool 12 strikes the surface, it is retracted until the proximity sensor 20 in the marking head 10 emits a signal. Since the distance from the completely extended striking tool 12 to the switchpoint of the sensor is known, the position of the workpiece surface can be precisely determined from the entire traveling distance and used for precisely setting the desired distance of the striking tool 12 from the workpiece 14 . This procedure as well helps to eliminate the negative effects of workpiece tolerances.
After a certain standstill period, the magnet keeper 9 sticks more firmly (adheres) in its rest position than during the stroke movements of the marking process. For this reason, the control unit can increase the acceleration current I 1 for the first stroke movement. This increase can be set by reference to stored tables as well.
The current control stage 17 can control the current values I 1 and I 2 or other current values simply by open-loop control, or it can be adapted as a stage for closed-loop current control.
As a variation of the embodiment explained above, a simple position sensor can also be provided instead of the position measuring device 20 ; this sensor would only emit a switchover signal in case a fixed predetermined position S 0 or S 1 , respectively, is reached. It can be e.g. an end position sensor which emits a signal when the rest position has been distanced by a certain distance S 0 or when the magnet keeper 9 has come closer by a certain distance S 1 during the return motion.
The control unit 16 shown in FIG. 2 is, for example, a microcomputer or microcontroller. The storage unit 23 will then be a non-volatile working memory of the microcontroller.
In FIG. 3 , a modified control unit 16 a is shown. Same or similarly working modules or elements are labeled with identical reference numbers and not again described in detail.
In the second embodiment, a time presetting stage 24 replaces the position presetting stage 19 . The time presetting stage 24 is triggered by a signal of the main controller 15 . After a certain time t 0 , switchover from the higher current value I 1 for the acceleration phase to the lower current value I 2 for the movement phase takes place. Correspondingly, the braking current is switched on during the return motion of the striking tool 12 after a time t 1 . The storage unit 23 contains the stored values t 0 and t 1 which are preset in the working parameter tables according to the first embodiment.
For open-loop and/or closed-loop control of the current, combinations of the two embodiments can also be implemented, i.e. the setting or control of the currents, respectively, take place partly depending on time and partly depending on the position. | A marking device for encoding metallic workpieces with two-dimensional matrix codes includes a striking tool for forming the code recesses, driven by an electromagnetic device. The driving movement is performed against the force of a return device. A positioning device displaceable on two axes (x, y) of a plane perpendicular to the striking direction (z) is used for positioning the striking tool in the desired code positions. An electronic control device for controlling movement of the striking tool includes means for presetting a higher current for the electromagnet device during a first acceleration phase of the striking tool and a lower current during a subsequent moving phase until the workpiece is impinged. In this manner, the precision of the code recesses in the workpiece can be exactly set or maintained, so that readability of the coding is substantially improved. | 1 |
BACKGROUND OF THE INVENTION
[0001] Strength and softness are important attributes in consumer products such as bathroom tissue, towels, and napkins. Strength and softness are strongly influenced by the sheet structure of a paper product. The mechanical treatment of fibers employed in the manufacture of paper products is an important factor in determining the strength and softness of products made from such fibers.
[0002] Strength and softness usually are inversely related. That is, the stronger a given sheet, the less softness that sheet is likely to provide. Likewise, a softer sheet is usually not as strong. Thus, this inverse relationship between strength and softness results in a constant endeavor in the industry to produce a sheet having a strength, which is at least as great as conventional sheets, but with improved softness. Also, a sheet that is at least as soft as known sheets, but with improved strength, also is desirable.
[0003] It is common in the manufacture of paper products to “crepe” the paper web by scraping the paper web from the surface of a heated dryer. Wet paper is applied to the dryer (sometimes called a Yankee dryer) with adhesive. A blade, sometimes known as a doctor blade, then may be used to remove the dried paper from the dryer surface. The blade usually is held against the surface of the rotating dryer at an angle.
[0004] The creping pocket, or pocket angle, is formed by the contact angle between the dryer and the surface of the doctor blade against which the paper web impacts. In general, using a lower angle causes more energy to be transferred to the tissue as it leaves the dryer surface. However, the increased energy will sometimes cause a failure at the web/adhesive interface resulting in folding of the sheet (as demonstrated by a coarse crepe) rather than compressive debonding which would yield a less dense and softer sheet.
[0005] As a general rule fibers having better softness are provided in outer layers of paper products—which routinely contact the skin of consumers. The inner layers of such paper products often comprise coarse fibers which are less desirable in their properties of softness, absorbency, or strength.
[0006] Sloughing of paper products, such as bath tissue, may be an important factor in tissue manufacture. Sloughing may be described generally as the loss of paper particles from the surface of the paper due to surface abrasion. Sloughing is undesirable. Unfortunately, sloughing sometimes is increased by the use of debonding agents. Debonding agents are used to soften paper products. Many consumers react negatively to paper that exhibits a high degree of sloughing. Therefore, efforts are made to provide a paper product that exhibits a minimal amount of sloughing.
[0007] It would be desirable to provide a process, system and resulting product showing capable of providing a high degree of softness and strength, with reduced amounts of sloughing.
SUMMARY OF THE INVENTION
[0008] In the invention, a method and system for manufacturing tissue products is provided. In the method, at least one papermaking furnish containing fibers is employed. Furthermore, a furnish is deposited upon a drying surface to form a paper web. Then, the drying surface is contacted with a creping blade, which is held against the drying surface at an angle of less than about 82%. In some applications, the paper web is combined with another paper web to form a multi-layered paper product, or tissue.
[0009] In some applications of the invention, it is desirable to use refined fibers. In other applications of the invention, the creping blade angle may be less than about 80%, or sometimes even less than about 78%.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] A full and enabling disclosure of this invention, including the best mode shown to one of ordinary skill in the art, is set forth in this specification.
[0011] [0011]FIG. 1 is a schematic flow diagram of one embodiment of a papermaking process that can be used in the present invention; and
[0012] [0012]FIG. 2 is a schematic flow diagram of another embodiment of a papermaking process that can be used in the present invention; and
[0013] [0013]FIG. 3 is a schematic representation of the creping pocket, illustrating the creping geometry; and
[0014] [0014]FIG. 4 is a perspective view of a machine used to measure slough of a paper sample; and
[0015] [0015]FIG. 5 comprises data generated in Examples 1-6, described below.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Reference now will be made to the embodiments of the invention, one or more examples of which are set forth below. Each example is provided by way of explanation of the invention, not as a limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in this invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present invention are disclosed in or are obvious from the following detailed description. It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary constructions.
[0017] Surprisingly, it has been discovered that a closed pocket creping angle affects the characteristics of tissue in a positive way. This affect may be even more pronounced when refined fibers are employed. Now, it has been discovered that using refined fibers also may produce a superior paper product. A wide variety of cellulosic fibers may be employed in the process of the present invention. In many embodiments of the invention, a first furnish comprising a strength layer is employed. This first furnish may be a softwood, for example. The average fiber length of a softwood fiber typically is about two to four times longer than a hardwood fiber. Softwood sources include trees sources, such as pines, spruces, and firs and the like.
[0018] Hardwood sources such as oaks, eucalyptuses, poplars, beeches, and aspens, may be used, but this list is by no means exhaustive of all the hardwood sources that may be employed in the practice of the invention. Fibers from different sources of wood exhibit different properties. Hardwood fibers, for example, tend to show high degrees of “fuzziness” or softness when placed on the exterior surface of a paper product, such as a bathroom tissue.
[0019] Illustrative cellulosic fibers that may be employed in the practice of the invention include, but are not limited to, wood and wood products, such as wood pulp fibers; non-woody paper-making fibers from cotton, from straws and grasses, such as rice and esparto, from canes and reeds, such as bagasse, from bamboos, form stalks with bast fibers, such as jute, flax, kenaf, cannabis, linen and ramie, and from leaf fibers, such as abaca and sisal. It is also possible to use mixtures of one or more cellulosic fibers.
[0020] As used herein, the term “fiber” or “fibrous” is meant to refer to a particulate material wherein the length to diameter ratio (aspect ratio) of such particulate material is greater than about 10. Conversely, a “nonfiber” or “nonfibrous” material is meant to refer to a particulate material wherein the length to diameter ratio of such particulate material is about 10 or less. It is generally desired that the cellulosic fibers used herein be wettable. Suitable cellulosic fibers include those which are naturally wettable. However, naturally non-wettable fibers can also be used.
[0021] In the practice of the present invention, it is desired that the cellulosic fibers be used in a form wherein the cellulosic fibers have already been prepared into a pulp. As such, the cellulosic fibers will be presented substantially in the form of individual cellulosic fibers, although such individual cellulosic fibers may be in an aggregate form such as a pulp sheet. This is in contrast with untreated cellulosic forms such as wood chips or the like. Thus, the current process is generally a post-pulping, cellulosic fiber separation process as compared to other processes that may be used for high-yield pulp manufacturing processes.
[0022] The preparation of cellulosic fibers from most cellulosic sources results in a heterogeneous mixture of cellulosic fibers. The individual cellulosic fibers in the mixture exhibit a broad spectrum of values for a variety of properties such as length, coarseness, diameter, curl, color, chemical modification, cell wall thickness, fiber flexibility, and hemicellulose and/or lignin content. As such, seemingly similar mixtures of cellulosic fibers prepared from the same cellulosic source may exhibit different mixture properties, such as freeness, water retention, and fines content because of the difference in actual cellulosic fiber make-up of each mixture or slurry.
[0023] In general, the cellulosic fibers may be used in the process of the present invention in either a dry or a wet state. However, it may be desirable to prepare an aqueous mixture comprising the cellulosic fibers wherein the aqueous mixture is agitated, stirred, or blended to effectively disperse the cellulosic fibers throughout the water.
[0024] The cellulosic fibers are typically mixed with an aqueous solution wherein the aqueous solution beneficially comprises at least about 30 weight percent water, suitably about 50 weight percent water, more suitably about 75 weight percent water, and most suitably about 100 weight percent water. When another liquid is employed with the water, such other suitable liquids include methanol, ethanol, isopropanol, and acetone. However, the use or presence of such other non-aqueous liquids may impede the formation of an essentially homogeneous mixture such that the cellulosic fibers do not effectively disperse into the aqueous solution and effectively or uniformly mix with the water. Such a mixture should generally be prepared under conditions that are sufficient for the cellulosic fibers and water to be effectively mixed together. Generally, such conditions will include using a temperature that is between about 10 degrees C. and about 100 degrees C.
[0025] In general, cellulosic fibers are prepared by pulping or other preparation processes in which the cellulosic fibers are present in an aqueous solution. The cellulosic fibers treated according to the process of the present invention are suited for use in disposable paper products such as facial or bathroom tissue, paper towels, wipes, napkins, and disposable paper products. Furthermore, other applications of the invention may be directed to products including: diapers, adult incontinent products, bed pads, sanitary napkins, tampons, other wipes, bibs, wound dressings, surgical capes or drapes.
Papermaking Processes
[0026] A papermaking process can be utilized to form a multi-layered paper web, such as described and disclosed in U.S. Pat. No. 5,129,988 to Farrinqton, Jr.; U.S. Pat. No. 5,494,554 to Edwards, et al.; and U.S. Pat. No. 5,529,665 to Kaun, which are incorporated herein in their entirety by reference thereto for all purposes.
[0027] In this regard, various embodiments of a method for forming a multi-layered paper web will now be described in more detail. Referring to FIG. 1, a method of making a wet-pressed tissue in accordance with one embodiment of the present invention is shown, commonly referred to as couch forming, wherein two wet web layers are independently formed and thereafter combined into a unitary web. To form the first web layer, a specified fiber (either hardwood or softwood) is prepared in a manner well known in the papermaking arts and delivered to the first stock chest 1 , in which the fiber is kept in an aqueous suspension. A stock pump 2 supplies the required amount of suspension to the suction side of the fan pump 4 . If desired, a metering pump 5 can supply an additive (e.g., latex, reactive composition, etc.) into the fiber suspension. Additional dilution water also is mixed with the fiber suspension.
[0028] The entire mixture of fibers is then pressurized and delivered to the headbox 6 . The aqueous suspension leaves the headbox 6 and is deposited on an endless papermaking fabric 7 over the suction box 8 . The suction box is under vacuum that draws water out of the suspension, thus forming the first layer. In this example, the stock issuing from the headbox 6 would be referred to as the “air side” layer, that layer eventually being positioned away from the dryer surface during drying.
[0029] The forming fabric can be any forming fabric, such as fabrics having a fiber support index of about 150 or greater. Some suitable forming fabrics include, but are not limited to, single layer fabrics, such as the Appleton Wire 94M available from Albany International Corporation, Appleton Wire Division, Menasha, Wis.; double layer fabrics, such as the Asten 866 available from Asten Group, Appleton, Wis.; and triple layer fabrics, such as the Lindsay 3080, available from Lindsay Wire, Florence, Miss.
[0030] The consistency of the aqueous suspension of papermaking fibers leaving the headbox can be from about 0.05 to about 2%, and in one embodiment, about 0.2%. The first headbox 6 can be a layered headbox with two or more layering chambers which delivers a stratified first wet web layer, or it can be a monolayered headbox which delivers a blended or homogeneous first wet web layer.
[0031] To form the second web layer, a specified fiber (either hardwood or softwood) is prepared in a manner well known in the papermaking arts and delivered to the second stock chest 11 , in which the fiber is kept in an aqueous suspension. A stock pump 12 supplies the required amount of suspension to the suction side of the fan pump 14 . A metering pump 5 can supply additives (e.g., latex, reactive composition, etc.) into the fiber suspension as described above. Additional dilution water 13 is also mixed with the fiber suspension. The entire mixture is then pressurized and delivered to the headbox 16 . The aqueous suspension leaves the headbox 16 and is deposited onto an endless papermaking fabric 17 over the suction box 18 . The suction box is under vacuum which draws water out of the suspension, thus forming the second wet web. In this example, the stock issuing from the headbox 16 is referred to as the “dryer side” layer as that layer will be in eventual contact with the dryer surface. Suitable forming fabrics for the forming fabric 17 of the second headbox include those forming fabrics previously mentioned with respect to the first headbox forming fabric.
[0032] After initial formation of the first and second wet web layers, the two web layers are brought together in contacting relationship (couched) while at a consistency of from about 10 to about 30%. Whatever consistency is selected, it is typically desired that the consistencies of the two wet webs be substantially the same. Couching is achieved by bringing the first wet web layer into contact with the second wet web layer at roll 19 .
[0033] After the consolidated web has been transferred to the felt 22 at vacuum box 20 , dewatering, drying and creping of the consolidated web is achieved in the conventional manner. More specifically, the couched web is further dewatered and transferred to a dryer 30 (e.g., Yankee dryer) using a pressure roll 31 , which serves to express water from the web, which is absorbed by the felt, and causes the web to adhere to the surface of the dryer. The web is then dried, optionally creped and wound into a roll 32 for subsequent converting into the final creped product.
[0034] [0034]FIG. 2 is a schematic flow diagram of another embodiment of a papermaking process that can be used in the present invention. For instance, a layered headbox 41 , a forming fabric 42 , a forming roll 43 , a papermaking felt 44 , a press roll 45 , a Yankee dryer 46 , and a creping blade 47 are shown. Also shown, but not numbered, are various idler or tension rolls used for defining the fabric runs in the schematic diagram, which may differ in practice. In operation, a layered headbox 41 continuously deposits a layered stock jet between the forming fabric 42 and the felt 44 , which is partially wrapped around the forming roll 43 . Water is removed from the aqueous stock suspension through the forming fabric 42 by centrifugal force as the newly-formed web traverses the arc of the forming roll. As the forming fabric 42 and felt 44 separate, the wet web stays with the felt 44 and is transported to the Yankee dryer 46 .
[0035] At the Yankee dryer 46 , the creping chemicals are continuously applied on top of the existing adhesive in the form of an aqueous solution. The solution is applied by any convenient means, such as using a spray boom that evenly sprays the surface of the dryer with the creping adhesive solution. The point of application on the surface of the dryer 46 is immediately following the creping doctor blade 47 , permitting sufficient time for the spreading and drying of the film of fresh adhesive.
[0036] [0036]FIG. 3 is a schematic view illustrating a typical creping operation, showing the creping geometry 121 . The creping pocket 122 forms a creping pocket angle 123 . This creping pocket angle 123 is formed by the angle between a tangent line 125 to the Yankee dryer 124 at the point of contact with the creping blade 126 , and the surface 128 of the creping blade 126 against which the sheet impacts.
[0037] The creping pocket angle 123 is schematically indicated by the double arrow in FIG. 3. The angle varies depending upon the particular paper product being formed, and may be adjusted to achieve certain desired results.
[0038] In general, lower angles cause more energy to be transferred to the paper web (not shown). However, the increased energy of a lowered creping pocket angle 123 sometimes causes a failure at the web/adhesive interface resulting in folding of the sheet (as demonstrated for example by a coarse crepe) rather than compressive debonding which would yield a less dense, softer product.
[0039] Unexpectedly, the adhesion derived from this invention allows the increased energy derived from closed pocket creping to result in a failure in the adhesive layer itself. This facilitates compressive debonding of the sheet, yielding a less dense and softer sheet.
[0040] The crepe that results from the application of the invention may provide a combination of both coarse and fine structures. The invention may employ a fine crepe structure superimposed upon an underlying coarse crepe structure. Thus, the fine structure confirms the effective break-up of the sheet while the underlying coarse structure enhances the perception of substance.
Stiffness
[0041] Stiffness (or softness) was ranked on a scale from 0 (described as pliable/flexible) to 16 (described as stiff/rigid). Twelve (12) panelists were asked to consider the amount of pointed, rippled or cracked edges or peaks felt from the sample while turning in your hand. The panelists were instructed to place two tissue samples flat on a smooth tabletop. The tissue samples overlapped one another by 0.5 inches (1.27 centimeters) and were flipped so that opposite sides of the tissue samples were represented during testing. With forearms/elbows of each panelist resting on the table, they placed their open hand, palm down, on the samples. Each was instructed to position their hand so their fingers were pointing toward the top of the samples, approximately 1.5 inches (approximately 3.81 centimeters) from the edge. Each panelist moved their fingers toward their palm with little or no downward pressure to gather the tissue samples. They gently moved the gathered samples around in the palm of their hand approximately 2 to 3 turns. The rank assigned by each panelist for a given tissue sample was then averaged and recorded.
Tensile (GMT) Strength Test Method
[0042] Tensile strength was reported as “GMT” (grams per 3 inches of a sample), which is the geometric mean tensile strength and is calculated as the square root of the product of MD tensile strength and CD tensile strength. MD and CD tensile strengths were determined using a MTS/Sintech tensile tester (available from the MTS Systems Corp., Eden Prairie, Minn.). Tissue samples measuring 3 inch wide were cut in both the machine and cross-machine directions. For each test, a sample strip was placed in the jaws of the tester, set at a 4 inch gauge length for facial tissue and 2 inch gauge length for bath tissue. The crosshead speed during the test was 10 in./minute. The tester was connected with a computer loaded with data acquisition system; e.g., MTS TestWork for windows software. Readings were taken directly from a computer screen readout at the point of rupture to obtain the tensile strength of an individual sample.
Refining of Fiber
[0043] Refining or beating of chemical pulps is the mechanical treatment and modification of fibers so that they can be formed into paper or board having desirable properties. It is used when preparing papermaking fibers for high-quality papers or paperboards, and in the past has not been widely employed for bathroom tissue or similar soft paper products.
[0044] Refining improves the bonding ability of fibers so that they form a strong and smooth paper sheet with good printing properties. Sometimes refining shortens fibers that are too long for a good sheet formation, or to develop other pulp properties such as absorbency, porosity, or optical properties specifically for a given paper grade.
[0045] A common refining or beating method is to treat fibers in the presence of water with metallic bars. The plates or fillings are grooved so that the bars that treat fibers and the grooves between bars allow fiber transportation through the refining machine. Such machines are known in the papermaking art.
[0046] Most refining is performed during a stage when bar edges give mechanical treatment and friction between fibers gives fiber-to-fiber treatment inside the floc. This stage continues until the leading edges reach the tailing edges of the opposite bars. After the edge-to-surface stage, the fiber bundle (floc) is still pressed between the flat bar surfaces until the tailing edge of the rotor bar has passed the tailing edge of the stator bar.
[0047] The refining results to a great extent depends on the stapling of fibers on the bar edges and on the behavior of the fibers in the floc during refining impacts. Long-fibered softwood pulps easily get stapled on the bar edges and build strong flocs that do not easily break in refining. Decreased gap clearance hastens refining degree change and increases fiber cutting. On the contrary, it is usually more difficult to get short-fibered hardwood pulps stapled on the bar edges, and such hardwood fibers may build weak flocs that easily break in refining. Decreased gap clearance means slower refining, in general.
[0048] The common feature of low-consistency refining theories is that the total or gross applied refiner power is divided into two components. The net refining power, which is the fiber-treating component, is the total absorbed refiner power minus no load power or idling power. The no load power is measured with water flowing through the running refiner, and the gap clearance is as narrow as possible without fillings or plates touching each other or any substantial increase in power. Total power, of course, depends on the actual running situation. Often the refining resistance of fibers determines the maximum loadability, but the ultimate limit is set by the torque moment of the refiner. This torque-based maximum total power increases linearly as the rotation speed of the refiner increases.
[0049] The amount of refining is described by means of the net energy input or the amount of net energy transferred to fibers. It is a practical way to evaluating the conditions inside the refiner. Fibers employed in this invention were refined, as measured in terms of HPD/T (horsepower days per metric ton of dry fiber) as reported in Table 1, for example.
Slough Measurement Methods and Apparatus
[0050] To determine the abrasion resistance or tendency of fibers to be rubbed from the web, samples were measured by abrading the tissue specimens by way of the following method. This test measures the resistance of tissue material to abrasive action when the material is subjected to a horizontally reciprocating surface abrader. All samples were conditioned at about 23° C. and about 50% relative humidity for a minimum of 4 hours.
[0051] [0051]FIG. 4 shows a diagram of the test equipment that may be employed to abrade a sheet. In FIG. 3, a machine 141 having a mandrel 143 receives a tissue sample 142 . A sliding magnetic clamp 148 with guide pins (not shown) is positioned opposite a stationary magnetic clamp 149 , also having guide pins ( 150 - 151 ). A cycle speed control 147 is provided, with start/stop controls 145 located on the upper panel, near the upper left portion of FIG. 4. A counter 146 is shown on the left side of machine 141 , which displays counts or cycles.
[0052] In FIG. 4, the mandrel 143 used for abrasion may consist of a stainless steel rod, about 0.5″ in diameter with the abrasive portion consisting of a 0.005″ deep diamond pattern extending 4.25″ in length around the entire circumference of the rod. The mandrel 143 is mounted perpendicular to the face of the machine 141 such that the abrasive portion of the mandrel 143 extends out from the front face of the machine 141 . On each side of the mandrel 143 are located guide pins 150 - 151 for interaction with sliding magnetic clamp 148 and stationary magnetic clamp 149 , respectively. These sliding magnetic clamp 148 and stationary magnetic clamp 149 are spaced about 4″ apart and centered about the mandrel 143 . The sliding magnetic clamp 148 and stationary magnetic clamp 149 are configured to slide freely in the vertical direction.
[0053] Using a die press with a die cutter, specimens are cut into 3″ wide×8″ long strips with two holes at each end of the sample. For tissue samples, the Machine Direction (MD) corresponds to the longer dimension. Each test strip is weighed to the nearest 0.1 mg. Each end of the sample 142 is applied upon the guide pins 150 - 151 and sliding magnetic clamp 148 and stationary magnetic clamp 149 to hold the sample 142 in place.
[0054] The mandrel 143 is then moved back and forth at an approximate 15 degree angle from the centered vertical centerline in a reciprocal horizontal motion against the test strip for 20 cycles (each cycle is a back and forth stroke), at a speed of about 80 cycles per minute, removing loose fibers from the web surface. Additionally the spindle 143 rotates counter clockwise (when looking at the front of the instrument) at an approximate speed of 5 revolutions per minute (rpm). The sliding magnetic clamp 148 and stationary magnetic clamp 149 then are removed from the sample 142 . Sample 142 is removed by blowing compressed air (approximately 5-10 psi) upon the sample 142 .
[0055] The sample 142 is weighed to the nearest 0.1 mg and the weight loss calculated. Ten test samples per tissue sample may be tested and the average weight loss value in milligrams is recorded. The result for each example was compared with a control sample containing no hairspray. Results are shown in FIG. 5, for control samples and for samples that have been treated according to the teachings of this invention.
[0056] Data from the following Examples 1-6 is shown in Table 1, and in graphic form in FIG. 6.
EXAMPLE 1
Control Sample Unrefined Fibers: Creping Pocket Angle of 82 Degrees
[0057] A soft tissue product to be used as control was made using a creping pocket angle of about 82 degrees, using unrefined fibers, as further described below. A layered headbox was employed. The first stock layer contained eucalyptus hardwood fiber which made up about 65% of the sheet by weight. This layer is the first layer to contact the forming fabric. Because it is transferred to a carrier felt, the hardwood layer also is the layer that contacts the drying surface. The second stock layer contained northern softwood fiber (designated LL-19). It comprised about 35% of the sheet by weight.
[0058] Permanent wet strength agent (Kymene, available from Hercules, Inc) was added in an amount equivalent to about 4 lbs/(about 0.2%) to the eucalyptus fiber and LL-19. The LL-19 fiber was not subjected to refining. A dry strength agent (Parez from Cytec) was added to the softwood side stock pump to adjust tensile strength. The machine speed of the 24-inch wide sheet was about 3000 feet per minute. The creping pocket angle was about 82 degrees. This tissue was piled together and calendered with two steel rolls at 30 pounds per lineal inch. This 2-ply product employed the dryer/softer eucalyptus layer plied to the outside of the product. The tissue was subjected to tensile test, slough test and panel softness evaluations.
EXAMPLE 2
Slightly Refined Fibers Creping Pocket Angle of 82 Degrees
[0059] Tissue sample was prepared as in Example 1 except that the LL-19 fiber fraction was subjected to refining with about 1.5 horsepower days per metric ton of dry fiber (HPD/T) energy input employed.
EXAMPLE 3
Moderately Refined Fibers Creping Pocket Angle of 82 Degrees
[0060] Tissue sample was prepared as the Example 1 except that the LL-19 was subjected to refining with about 3.0 HPD/T energy input.
EXAMPLE 4
Highly Refined Fibers Creping Pocket Angle of 82 Degrees
[0061] Tissue sample was prepared as the Example 1 except that the LL-19 was subjected to refining with 6.0 HPD/T energy input.
EXAMPLE 5
Moderately Refined Fibers Creping Pocket Angle of 75 Degrees
[0062] Tissue sample was prepared as the Example 1 except that the LL-19 was subjected to refining with about 3.0 HPD/T energy input and pocket creping angle of about 75 degrees.
EXAMPLE 6
Highly Refined Fibers Creping Pocket Angle of 75 Degrees
[0063] Tissue sample was prepared as in Example 1 except that the LL-19 was subjected to refining with 6.0 HPD/T energy input and pocket creping angle is 75 degrees.
TABLE 1 Horsepower Days Per Metric Ton Geometric of Dry Fiber Mean (HPD/T) on Tensile LL-19 Creping Strength product Angle (GMT) Slough Softness Example 1 0 82 660 12.5 8.26 Unrefined Example 2 1.5 82 629 13.2 8.31 Refined Example 3 3 82 639 12.4 8.21 Refined Example 4 6 82 708 9.7 8.08 Refined Example 5 3 75 658 11.23 8.33 Refined Example 6 6 75 669 10.27 8.22 Refined
[0064] No data has been accumulated for the following Examples 7-12.
EXAMPLE 7
Slightly Refined Fibers Creping Pocket Angle of 80 Degrees
[0065] Tissue sample was prepared as in Example 1 except that the creping pocket angle is 80 degrees, and the LL-19 fiber fraction was subjected to refining with about 1.5 horsepower days per metric ton of dry fiber (HPD/T) energy input employed.
EXAMPLE 8
Moderately Refined Fibers Creping Pocket Angle of 80 Degrees
[0066] Tissue sample was prepared as the Example 7 (angle of 80 degrees) except that the LL-19 was subjected to refining with about 3.0 HPD/T energy input.
EXAMPLE 9
Highly Refined Fibers Creping Pocket Angle of 80 Degrees
[0067] Tissue sample was prepared as the Example 7 (angle of 80 degrees) except that the LL-19 was subjected to refining with 6.0 HPD/T energy input.
EXAMPLE 10
Slightly Refined Fibers Creping Pocket Angle of 78 Degrees
[0068] Tissue sample was prepared as the Example 1 except that the creping pocket angle was 78 degrees, and the LL-19 was subjected to refining with about 1.5 HPD/T energy.
EXAMPLE 11
Moderately Refined Fibers Creping Pocket Angle of 78 Degrees
[0069] Tissue sample was prepared as in Example 10 except that the LL-19 was subjected to refining with about 3.0 HPD/T energy.
EXAMPLE 12
Highly Refined Fibers Creping Pocket Angle of 78 Degrees
[0070] Tissue sample was prepared as in Example 10 except that the LL-19 was subjected to refining with about 6.0 HPD/T energy.
[0071] When comparing Example 1 with Examples 2-4 it can be seen that employing refined fibers having an increasing amount of refinement, at a given creping angle, tends to decrease the amount of tissue slough that is observed. This decreased slough coincides with only a relatively minor loss in softness.
[0072] Furthermore, comparing Examples 5 and 6 with Examples 3 and 4, respectively, shows that using refined fibers in combination with a 75 degree closed pocket creping angle produces a paper product having, in general, better slough and softness properties.
[0073] Refining may reduce slough from paper products, even though softness also may be adversely affected. Closed pocket creping at less than about 82 degrees combined with refined softwood tends to produce a softer tissue with less slough.
[0074] It is understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary constructions. The invention is shown by example in the appended claims. | A process and product of making an absorbent paper article such as paper products, towels, and napkins from a paper web is disclosed. A process for making a product having superior properties of softness, handfeel, and strength is shown. The product may exhibit reduced sloughing, that is, a reduction in the amount of paper particles or flakes generated from the product upon abrasion of the product. A furnish that uses refined fibers may be employed. Furthermore, it is sometimes advantageous to use a closed pocket creping angle when creping the paper web from the surface of a rotating dryer. | 3 |
CROSS REFERENCES TO RELATED APPLICATIONS
U.S. patent application Ser. No. 13/305,849 entitled “Air Extraction Momentum Method,” filed concurrently herewith (now U.S. Pat. No. 8,449,092), and U.S. patent application Ser. No. 13/305,828 entitled “Air Extraction Momentum Pump for Inkjet Printhead,” filed concurrently herewith (now U.S. Pat. No. 8,454,145) are assigned to the same assignee hereof, Eastman Kodak Company of Rochester, N.Y., and contain subject matter related, in certain respect, to the subject matter of the present application. The above-identified patent applications are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
This invention relates generally to the field of inkjet printing, and in particular to an air extraction device for removing air from the printhead while in the printer.
BACKGROUND OF THE INVENTION
An inkjet printing system typically includes one or more printheads and their corresponding ink supplies. A printhead includes an ink inlet that is connected to its ink supply and an array of drop ejectors, each ejector including an ink pressurization chamber, an ejecting actuator and a nozzle through which droplets of ink are ejected. The ejecting actuator may be one of various types, including a heater that vaporizes some of the ink in the chamber in order to propel a droplet out of the nozzle, or a piezoelectric device that changes the wall geometry of the ink pressurization chamber in order to generate a pressure wave that ejects a droplet. The droplets are typically directed toward paper or other print medium (sometimes generically referred to as recording medium or paper herein) in order to produce an image according to image data that is converted into electronic firing pulses for the drop ejectors as the print medium is moved relative to the printhead.
Motion of the print medium relative to the printhead can include keeping the printhead stationary and advancing the print medium past the printhead while the drops are ejected. This architecture is appropriate if the nozzle array on the printhead can address the entire region of interest across the width of the print medium. Such printheads are sometimes called pagewidth printheads. A second type of printer architecture is the carriage printer, where the printhead nozzle array is somewhat smaller than the extent of the region of interest for printing on the print medium and the printhead is mounted on a carriage. In a carriage printer, the print medium is advanced a given distance along a print medium advance direction and then stopped. While the print medium is stopped, the printhead carriage is moved in a carriage scan direction that is substantially perpendicular to the print medium advance direction as the drops are ejected from the nozzles. After the carriage has printed a swath of the image while traversing the print medium, the print medium is advanced, the carriage direction of motion is reversed, and the image is formed swath by swath.
Inkjet ink includes a variety of volatile and nonvolatile components including pigments or dyes, humectants, image durability enhancers, and carriers or solvents. A key consideration in ink formulation and ink delivery is the ability to produce high quality images on the print medium. Image quality can be degraded if air bubbles block the small ink passageways from the ink supply to the array of drop ejectors. Such air bubbles can cause ejected drops to be misdirected from their intended flight paths, or to have a smaller drop volume than intended, or to fail to eject. Air bubbles can arise from a variety of sources. Air that enters the ink supply through a non-airtight enclosure can be dissolved in the ink, and subsequently be exsolved (i.e. come out of solution) from the ink in the printhead at an elevated operating temperature, for example. Air can also be ingested through the printhead nozzles. For a printhead having replaceable ink supplies, such as ink tanks, air can also enter the printhead when an ink tank is changed.
In a conventional inkjet printer, a part of the printhead maintenance station is a cap that is connected to a suction pump, such as a peristaltic or tube pump. The cap surrounds the printhead nozzle face during periods of nonprinting in order to inhibit evaporation of the volatile components of the ink. Periodically, the suction pump is activated to remove ink and unwanted air bubbles from the nozzles. This pumping of ink through the nozzles is not a very efficient process and wastes a significant amount of ink over the life of the printer. Not only is ink wasted, but in addition, a waste pad must be provided in the printer to absorb the ink removed by suction. The waste ink and the waste pad are undesirable expenses. In addition, the waste pad takes up space in the printer, requiring a larger printer volume. Furthermore the waste ink and the waste pad must be subsequently disposed. Also, the suction operation can delay the printing operation
Co-pending U.S. Patent Application Publication No. 2011/0209706 entitled “Air Extraction Device for Inkjet Printhead” discloses an inkjet printhead including an air extraction chamber having a compressible member for forcing air to be vented from an air chamber through a one-way relief valve in its open position, and for applying a reduced air pressure to a membrane while the one-way relief valve is in its closed position. The compressible member, for example a bellows, is compressed by a projection from a wall of the printer when the carriage moves to an end of travel. Co-pending U.S. patent application Ser. No. 13/095,998 filed on Apr. 28, 2011, is a related design that uses a piston assembly rather than a compressible member, the piston being moved to a first position by a projection from a wall of the printer when the carriage moves to an end of travel. Both of these air extraction devices are actuated by moving the carriage to an end of travel. Both of these copending patent applications are incorporated by reference herein in their entireties.
U.S. Pat. No. 6,116,726, entitled “Ink Jet Printer Cartridge with Inertially-Driven Air Evacuation Apparatus and Method”, discloses an inkjet printhead (or pen) including a movable inertia element connected to the body of the printhead. The body defines an ink chamber and an air outlet. A compressor element is connected to the inertia element and the air outlet. When the printhead is accelerated along the carriage path during printing, the resulting motion of the inertia element operates the compressor to pump a small amount of air from the chamber. Such a pump is actuated as the carriage moves back and forth during the normal printing process and does not require the carriage to move to an end of travel in order to encounter a projection from a carriage wall. However, the design of the compressor element is somewhat complex.
What is needed is an air extraction device for an inkjet printhead that is actuated as the carriage moves back and forth during the normal printing process, but has a simpler design.
SUMMARY OF THE INVENTION
A preferred embodiment of the present invention comprises a method of making an ink cartridge by forming the ink cartridge with an ink chamber and an air accumulation chamber, forming a vent hole at a first end of the air accumulation chamber, and disposing a one way valve at the vent hole for preventing gas from entering the air accumulation chamber through the vent hole. A narrower a neck region fluidically connects the ink chamber and the air accumulation chamber within the ink cartridge. A mass is placed within the air accumulation chamber, the mass having a dimension smaller than an interior dimension of the air accumulation chamber such that the mass is movable between the first end and a second end of the air accumulation chamber. The mass has a dimension greater than the neck region for preventing the mass from entering the ink chamber. The mass comprises an average density of less than two grams per cubic centimeter and has a through-hole such that a first end of the through-hole faces the first end of the air accumulation chamber and a second end of the through-hole faces the second end of the air accumulation chamber. A one way valve at the first end of the through-hole prevents gas from entering the through-hole through the first end of the through hole.
Another preferred embodiment of the present invention comprises a method of making an ink cartridge by forming an ink cartridge having a first chamber for holding ink and a second chamber smaller than the first chamber for holding a smaller portion of the ink and for holding air, including forming a neck region for fluidically connecting the first chamber and the second chamber. A vent hole is formed at a first end of the first chamber for evacuating a portion of the air.
A mass is disposed within the first chamber and has a dimension smaller than an interior dimension of the first chamber such that the mass is movable between the first end and a second end of the first chamber. It is also large enough such that air is forced out of the vent hole when the mass moves in a direction toward the first end of the first chamber. The neck region is formed proximate the second end of the first chamber so that there is enough air space in the first chamber between the first end of the mass and the vent hole to capture air to be forced out of the vent hole when the mass moves toward the vent hole. The mass has a through hole and a one way valve at a first end of the through-hole for preventing gas from entering the through-hole through the first end of the through hole. The vent hole also has a one way valve for preventing air from entering the first chamber through the vent hole. A density of the ink and the mass has the following relationship: if the ink comprises a density d i grams/cm 3 , then the mass is formed such that the mass has an effective density d m grams/cm 3 , wherein 0.8d i <d m <1.2d i .
These, and other, aspects and objects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating preferred embodiments of the present invention and numerous specific details thereof, is given by way of illustration and not of limitation. For example, the summary descriptions above are not meant to describe individual separate embodiments whose elements are not interchangeable. In fact, many of the elements described as related to a particular embodiment can be used together with, and possibly interchanged with, elements of other described embodiments. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. It is to be understood that the attached drawings are for purposes of illustrating the concepts of the invention. The figures below are intended to be drawn neither to any precise scale with respect to relative size, angular relationship, or relative position nor to any combinational relationship with respect to interchangeability, substitution, or representation of an actual implementation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of an inkjet printer system;
FIG. 2 is a schematic perspective of a portion of a carriage printer according to an embodiment of the invention;
FIG. 3 shows a cross-section of a printhead according to an embodiment of the invention;
FIG. 4 shows a cross-section of the printhead of FIG. 3 with the one-way valve open over the air vent opening;
FIG. 5 shows a cross-section of a printhead according to another embodiment of the invention;
FIG. 6 shows a cross-section of a printhead according to yet another embodiment of the invention;
FIG. 7 shows a bottom view of a printhead die;
FIG. 8 shows a schematic top view of a configuration of ink tanks and a printhead having chambers having noncollinear chamber axes; and
FIG. 9 shows a schematic top view of a configuration of ink tanks and a printhead having chambers having collinear chamber axes.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 , a schematic representation of an inkjet printer system 10 is shown, for its usefulness with the present invention and is fully described in U.S. Pat. No. 7,350,902, which is incorporated by reference herein in its entirety. Inkjet printer system 10 includes an image data source 12 , which provides data signals that are interpreted by a controller 14 as being commands to eject drops. Controller 14 includes an image processing unit 15 for rendering images for printing, and outputs signals to an electrical pulse source 16 of electrical energy pulses that are inputted to an inkjet printhead 100 , which includes at least one inkjet printhead die 110 . Inkjet printhead die 110 are sometimes interchangeably called ejector die herein.
In the example shown in FIG. 1 , there are two nozzle arrays. Nozzles 121 in the first nozzle array 120 have a larger opening area than nozzles 131 in the second nozzle array 130 . In this example, each of the two nozzle arrays has two staggered rows of nozzles, each row having a nozzle density of 600 per inch. The effective nozzle density then in each array is 1200 per inch (i.e. d= 1/1200 inch in FIG. 1 ). If pixels on the recording medium 20 were sequentially numbered along the paper advance direction, the nozzles from one row of an array would print the odd numbered pixels, while the nozzles from the other row of the array would print the even numbered pixels.
In fluid communication with each nozzle array is a corresponding ink delivery pathway. Ink delivery pathway 122 is in fluid communication with the first nozzle array 120 , and ink delivery pathway 132 is in fluid communication with the second nozzle array 130 . Portions of ink delivery pathways 122 and 132 are shown in FIG. 1 as openings through printhead die substrate 111 . One or more inkjet printhead die 110 will be included in inkjet printhead 100 , but for greater clarity only one inkjet printhead die 110 is shown in FIG. 1 . In FIG. 1 , first fluid source 18 supplies ink to first nozzle array 120 via ink delivery pathway 122 , and second fluid source 19 supplies ink to second nozzle array 130 via ink delivery pathway 132 . Although distinct fluid sources 18 and 19 are shown, in some applications it may be beneficial to have a single fluid source supplying ink to both the first nozzle array 120 and the second nozzle array 130 via ink delivery pathways 122 and 132 respectively. Also, in some embodiments, fewer than two or more than two nozzle arrays can be included on printhead die 110 . In some embodiments, all nozzles on inkjet printhead die 110 can be the same size, rather than having multiple sized nozzles on inkjet printhead die 110 .
Not shown in FIG. 1 , are the drop forming mechanisms associated with the nozzles. Drop forming mechanisms can be of a variety of types, some of which include a heating element to vaporize a portion of ink and thereby cause ejection of a droplet, or a piezoelectric transducer to constrict the volume of a fluid chamber and thereby cause ejection, or an actuator which is made to move (for example, by heating a bi-layer element) and thereby cause ejection. In any case, electrical pulses from electrical pulse source 16 are sent to the various drop ejectors according to the desired deposition pattern. In the example of FIG. 1 , droplets 181 ejected from the first nozzle array 120 are larger than droplets 182 ejected from the second nozzle array 130 , due to the larger nozzle opening area. Typically other aspects of the drop forming mechanisms (not shown) associated respectively with nozzle arrays 120 and 130 are also sized differently in order to optimize the drop ejection process for the different sized drops. During operation, droplets of ink are deposited on a recording medium 20 . As the nozzles are the most visible part of the drop ejector, the terms drop ejector array and nozzle array will sometimes be used interchangeably herein.
FIG. 2 shows a schematic perspective of a portion of a desktop carriage printer according to an embodiment of the invention. Some of the parts of the printer have been hidden in the view shown in FIG. 2 so that other parts can be more clearly seen. Printer chassis 300 has a print region 303 across which carriage 200 is moved back and forth in reciprocative fashion along carriage scan direction 305 , while drops of ink are ejected from printhead 250 that is mounted on carriage 200 . Near the end of each printing swath, carriage 220 is decelerated, stopped, and accelerated in the opposite direction to reach a printing velocity in the opposite direction. The magnitude of the carriage acceleration is typically between 1 g and 3 g, where g is the acceleration due to gravity. The letters ABCD indicate a portion of an image that has been printed in print region 303 on a piece 371 of paper or other recording medium. Carriage motor 380 moves belt 384 to move carriage 200 along carriage guide rod 382 . An encoder sensor (not shown) is mounted on carriage 200 and indicates carriage location relative to an encoder 383 .
Printhead 250 is mounted on carriage 200 , and ink tanks 262 are mounted to supply ink to printhead 250 , and contain inks such as cyan, magenta, yellow and black, or other recording fluids. Optionally, several ink tanks can be bundled together as one multi-chamber ink supply, for example, cyan, magenta and yellow. Inks from the different ink tanks 262 are provided to different nozzle arrays, as described in more detail below.
A variety of rollers are used to advance the recording medium through the printer. In the view of FIG. 2 , feed roller 312 and passive roller(s) 323 advance piece 371 of recording medium along media advance direction 304 , which is substantially perpendicular to carriage scan direction 305 across print region 303 in order to position the recording medium for the next swath of the image to be printed. Discharge roller 324 continues to advance piece 371 of recording medium toward an output region where the printed medium can be retrieved. Star wheels (not shown) hold piece 371 of recording medium against discharge roller 324 .
Typical lengths of recording media are 6 inches for photographic prints (4 inches by 6 inches) or 11 inches for paper (8.5 by 11 inches). Thus, in order to print a full image, a number of swaths are successively printed while moving printhead chassis 250 across the piece 371 of recording medium. Following the printing of a swath, the recording medium 20 is advanced along media advance direction 304 . Feed roller 312 can include a separate roller mounted on the feed roller shaft, or can include a thin high friction coating on the feed roller shaft. A rotary encoder (not shown) can be coaxially mounted on the feed roller shaft in order to monitor the angular rotation of the feed roller 312 . The motor that powers the paper advance rollers, including feed roller 312 and discharge roller 324 , is not shown in FIG. 2 . For normal paper feeding feed roller 312 and discharge roller 324 are driven in forward rotation direction 313 .
Toward the rear of the printer chassis 300 , in this example, is located the electronics board 390 , which includes cable connectors for communicating via cables (not shown) to the printhead carriage 200 and from there to the printhead 250 . Also on the electronics board are typically mounted motor controllers for the carriage motor 380 and for the paper advance motor, a processor and/or other control electronics (shown schematically as controller 14 and image processing unit 15 in FIG. 1 ) for controlling the printing process, and an optional connector for a cable to a host computer.
Toward the right side of the printer chassis 300 , in the example of FIG. 2 , is the maintenance station 330 . Maintenance station 330 can include a wiper (not shown) to clean the nozzle face of printhead 250 , as well as a cap 332 to seal against the nozzle face in order to slow the evaporation of volatile components of the ink. Many conventional printers include a vacuum pump attached to the cap in order to suck ink and air out of the nozzles of printhead when they are malfunctioning.
A different way to remove air from the printhead 250 is shown in FIG. 2 and discussed in more detail below relative to embodiments of the present invention. Printhead 250 includes one or more air accumulation chambers 220 in which is disposed a movable mass 222 . An ink chamber 242 is connected to each air accumulation chamber 220 . Internal walls 241 (represented by dashed lines) provide separation between adjacent ink chambers 242 . Four ink chambers 242 are shown in the example of FIG. 2 , corresponding to cyan, magenta, yellow and black inks. Similarly, four ink tanks 262 are shown. However, in other examples, there can be more than four ink chambers 242 or fewer than four ink chambers 242 .
FIG. 3 shows a cross-section of a printhead 250 similar to the printhead 250 shown in FIG. 2 , where the cross-section is through a plane parallel to an internal wall 241 . Inkjet printhead 250 includes a printhead body 240 and a printhead die 251 (that is, an ejector die). Printhead body includes an ink chamber 242 containing an ink 243 . Ink chamber 242 includes an ink inlet port 245 and an ink outlet 248 that is fluidically connected to printhead die 251 . Printhead body also includes an air accumulation chamber 220 having a chamber axis 221 . Preferably, chamber axis 221 is parallel to carriage scan direction 305 when printhead 250 is mounted on carriage 200 (see FIG. 2 ). Near one end 227 of air accumulation chamber 220 is an air vent opening 228 . Inside air accumulation chamber is a mass 222 that is movable along chamber axis 221 toward and away from the end 227 that is near air vent opening 228 . A neck region 239 connects ink chamber 242 and air accumulation chamber 220 , so that ink 243 is typically in the ink chamber, the neck region 239 and the air accumulation chamber 220 . An air space 217 is located above the level of the ink 243 in the air accumulation chamber 220 .
An ink source such as ink tank 262 is fluidically connected to printhead body 240 at ink inlet port 245 in order to replenish ink 243 in ink chamber 242 to replace ink that is used during printing. The ink source typically includes a pressure regulation mechanism (not shown) in order to keep ink 243 at a sufficiently negative pressure that it does not drool out the nozzles (not shown) in nozzle face 252 . As ink 243 exits ink chamber 243 through ink outlet 248 , the volume of air space 217 increases, thereby reducing the air pressure in air space 217 . This reduced air pressure draws ink 243 from the ink source (such as replaceable ink tank 262 that is mountable on printhead 250 ) through ink outlet port 263 that mates with ink inlet port 245 in order to replenish the ink 243 in ink chamber 242 and air accumulation chamber 220 . Typically a porous filter 247 is disposed at the entry to ink inlet port 245 .
Although a replaceable ink tank 262 is one type of ink source, alternatively an off-axis ink source (not shown) that is stationarily mounted on the printer chassis 300 ( FIG. 2 ) can be fluidically connected to ink chamber 243 via flexible tubing (not shown). Also, although ink inlet port 245 is shown in FIG. 3 as extending outwardly from printhead body 240 along carriage scan direction 305 near a lower region of printhead body 240 close to ink outlet 248 , in other examples, ink inlet port 245 can extend outwardly from printhead body 240 out of the plane of FIG. 3 , or in other directions. In other examples, ink inlet port 245 can be located closer to air accumulation chamber 220 than to ink outlet 248 . In some examples, ink tank 262 can be mounted on top of air accumulation chamber 220 .
In FIG. 3 , air bubbles 244 are shown as rising both from ink outlet 248 and from ink inlet port 245 of printhead 250 . Air bubbles 244 originating at ink outlet 248 can come, for example, from printhead die 251 due to air ingested through the nozzles or to air coming out of solution from the ink 243 at elevated temperatures. Air bubbles 244 originating at inlet ports 245 can enter, for example, during the changing of ink tanks 262 . As discussed below, the movable mass 222 in air accumulation chamber 220 is effective in removing air due to various sources in printhead 250 . The open vertical geometry of ink chamber 242 , leading to an air space 217 above ink 243 in air accumulation chamber 220 , facilitates the free rising of air bubbles 244 through ink 243 , due to their buoyancy, toward the air space 217 . With a porous filter 247 disposed at the ink inlet port 245 , no additional filter is typically required along an ink path between the air accumulation chamber 220 and the ink outlet 248 of the ink chamber 248 . Thus, the rising of air bubbles is not hindered as it would be by the fine mesh screen (42) in FIG. 2 of U.S. Pat. No. 6,116,726, described in the Background section herein.
Further details will now be provided in order to explain how excess air (from air bubbles 244 ) in air space 217 is removed from air accumulation chamber 220 . Air accumulation chamber 220 includes a first wall 225 located near neck region 239 and a second wall 226 located opposite first wall 225 . Air vent opening 228 is located in or near second wall 226 . A one-way valve 229 covers air vent opening 228 . In the example shown in FIGS. 3 and 4 , one way valve 229 includes a flapper valve having a free end 230 that is located near the second wall 226 of the air accumulation chamber 220 , and is outside the air accumulation chamber 220 . Under normal conditions ( FIG. 3 ), elastomeric restoring forces keep the free end 230 sealed against air vent opening 228 , so that air does not enter or exit air vent opening 228 . As mass 222 moves in a direction from first wall 225 toward second wall 226 , the air pressure in the region between mass 222 and second wall 226 increases as the volume therein decreases. When the air pressure exceeds a cracking pressure of the one-way valve 229 , the free end 230 is forced away from air vent opening 228 as in FIG. 4 and letting some air escape from air accumulation chamber 220 . Then elastomeric restoring forces close the one-way valve 229 again ( FIG. 3 ), so that air can no longer enter or exit air vent opening 228 .
Mass 222 is moved back and forth along chamber axis 221 due to forces (inertia, momentum) arising from carriage acceleration and deceleration at least at both ends of carriage travel. The force on mass 222 will exceed the force on the ink 243 in air accumulation chamber 220 , if the density of mass 222 is greater than the average density of the ink 243 and the air in air space 217 . If the density of mass 222 is the same as the average density of ink 243 and air in air space 217 , there will be no differential force to move mass 222 along chamber axis 221 . Typically the density of mass 222 is on the order of the density of ink 243 that is on the order of 1 gram /cm 3 . To keep the mass 222 from moving too quickly in air accumulation chamber 220 (tending to force ink out of air vent opening 228 ), the density or average density of mass 222 is typically less than 2 grams/cm 3 .
A dimension of mass 222 is preferably greater than a dimension of neck region 239 , thereby constraining the mass 222 from passing through neck region 239 and entering ink chamber 243 . In the example of FIG. 3 , length dimensions are indicated as being parallel to chamber axis 221 and width dimensions are indicated as being perpendicular to chamber axis 221 . Length L N of neck region 239 is less than length L C of air accumulation chamber 220 . Length L M of mass 222 is greater than length L N of neck region 239 , but is less than length L C of air accumulation chamber 220 . Width W M of mass 222 is less than width W C of air accumulation chamber 220 , thereby providing a gap. It is not required that the seals between mass 222 and the walls of air accumulation chamber 220 be airtight. An air gap between mass 222 and the walls of air accumulation chamber 220 allows free movement of mass 222 without excessive pressure build-up.
Mass 222 can have a variety of shapes, but it is typically advantageous for low friction travel along chamber axis 221 if mass 222 includes a circular cross-section in a plane perpendicular to chamber axis 221 . In the example of FIGS. 3 and 4 , it is advantageous if mass 222 has the shape of a right circular cylinder. In the example of printhead 250 in FIG. 5 , mass 222 has the shape of a sphere.
As described above relative to FIGS. 3 and 4 , it is desirable to build up pressure in the region of air accumulation chamber 220 that is near air vent opening 228 in order to expel air through one way valve 229 as mass 222 moves toward the air vent opening 228 . However, in some embodiments it is not desirable to build up pressure on the other side of mass 222 , as mass 222 moves away from air vent opening 228 . Such a buildup of pressure can cause an undesirable pressure surge toward ink outlet 248 and ink inlet port 245 . FIG. 6 shows a cross-sectional view in which mass 222 includes a through hole 223 extending from a first face 218 , which can be considered as a front face, that is proximate to air vent opening 228 (and distal to neck region 239 ) to a second face 219 , which can be considered as a rear face, that is distal to air vent opening 228 . Included on first face 218 is a one-way valve 224 , such as a flapper valve. As mass 222 moves along chamber axis 221 toward air vent opening 228 , one-way valve 224 is held in the closed position (e.g. by elastomeric forces) so that it seals against through hole 223 . As a result, air and ink cannot flow through the through hole 223 when mass 222 moves toward air vent opening 228 , so pressure can build up to open one-way valve 229 as in FIG. 4 . However, as mass 222 moves along chamber axis 221 away from air vent opening 228 , pressure that is built up in the region of air accumulation chamber 220 between second face 219 and wall 225 is relieved when the increased pressure causes one-way valve 224 on first face 218 of mass 222 to open, as shown in FIG. 6 . Although the through hole 223 is shown as parallel to air chamber axis 221 in FIG. 6 , and front face 218 and rear face 219 is shown as perpendicular to air chamber axis 221 therein, the air gap between mass 222 and the walls of air accumulation chamber 220 allows a slight tilting of mass 222 with respect thereto, and so these parallel and perpendicular relationships remain “substantially parallel” and “substantially perpendicular”.
A mass 222 having a through hole 223 has an effective density that is an average of the density of solid material that mass 222 is made of and the density of the air or ink in through hole 223 . If the ink has a density d i grams/cm 3 , then for effective pumping, without over-pumping, it is desirable for the mass 222 to have an effective density of d m grams/cm 3 , where 0.8d i <d m <1.2d i .
In the examples shown in FIG. 3 , near the air vent opening 228 is a cap assembly 237 . An inner cap 231 includes air vent opening 228 and one-way valve 229 covering the air vent opening 228 . Inner cap 231 is affixed to air accumulation chamber 220 at interface 234 . A second cap 232 is affixed over inner cap 231 and includes a breather membrane 233 through which air can readily pass, but through which ink cannot readily pass. Breather membrane 233 is outside air accumulation chamber 220 . If some ink 243 is inadvertently forced through air vent opening 228 , it can collect in the region between inner cap 231 and second cap 232 . Breather membrane 233 is in a vertical orientation, so that ink tends to run off it and not degrade its permeability to air. One way valve 229 is disposed between breather membrane 233 and the interface 234 between inner cap 231 and air accumulation chamber 220 . Outer cap 235 includes a tortuous vent path 236 that allows air to pass through to outside printhead 250 , but would inhibit accumulated ink from dripping out if the printhead 250 were removed from carriage 200 ( FIG. 2 ) and turned upside down.
FIG. 7 shows a bottom view of printhead die 251 (i.e. ejector die). Nozzle arrays 257 , included in nozzle face 252 , are disposed along nozzle array direction 254 that is substantially parallel to media advance direction 304 (see FIG. 2 ) when printhead 250 is installed in carriage 200 . Chamber axis 221 (see FIG. 3 ) is substantially parallel to nozzle face 252 and substantially perpendicular to array direction 254 . Ink feed(s) 255 bring ink from mounting substrate ink passageway(s) 259 (see FIG. 3 ) to nozzle arrays 257 .
In FIG. 2 , the ink connections between ink tanks 262 and ink chambers 242 are not visible. FIGS. 8 and 9 schematically show top views of two different configurations of ink connections. Ink chambers (not shown) and air accumulation chambers 220 , are similar to those described above relative to FIG. 3 , for example. FIG. 8 shows a configuration similar to that of FIG. 2 where there are a plurality of ink tanks 262 (designated K, C, M and Y for black, cyan, magenta and yellow inks) including air accumulation chambers 220 , such that the different air accumulation chambers 220 have chamber axes 221 that are not collinear. Ink connection lines 265 bring ink from ink tanks 262 to corresponding chambers in printhead 250 . By contrast, in the configuration shown in FIG. 9 the chamber axes 221 of different air accumulation chambers 220 are collinear.
Because embodiments of this invention extract air without extracting ink, less ink is wasted than in conventional printers. The waste ink pad used in conventional printers can be eliminated, or at least reduced in size to accommodate maintenance operations such as spitting from the jets. This allows the printer to be more economical to operate, more environmentally friendly and more compact. Furthermore, since the air extraction method of the present invention is done during printing, it is not necessary to delay printing operations to extract air from the printhead.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
PARTS LIST
10 Inkjet printer system
12 Image data source
14 Controller
15 Image processing unit
16 Electrical pulse source
18 First fluid source
19 Second fluid source
20 Recording medium
100 Inkjet printhead
110 Inkjet printhead die
111 Substrate
120 First nozzle array
121 Nozzle(s)
122 Ink delivery pathway (for first nozzle array)
130 Second nozzle array
131 Nozzle(s)
132 Ink delivery pathway (for second nozzle array)
181 Droplet(s) (ejected from first nozzle array)
182 Droplet(s) (ejected from second nozzle array)
200 Carriage
217 Air space
218 First face (of mass)
219 Second face (of mass)
220 Air accumulation chamber
221 Chamber axis
222 Mass
223 Through hole
224 One-way valve (on first face of mass)
225 First wall
226 Second wall
227 End (of air accumulation chamber)
228 Air vent opening
229 One-way valve
230 Free end
231 Inner cap
232 Second cap
233 Breather membrane
234 Interface
235 Outer cap
236 Tortuous vent path
237 Cap assembly
239 Neck region
240 Printhead body
241 Internal wall
242 Ink chamber
243 Ink
244 Air bubble(s)
245 Ink inlet port
246 Ink outlet
247 Porous filter
248 Ink outlet
250 Printhead
251 Printhead die
252 Nozzle face
253 Nozzle array
254 Nozzle array direction
255 Ink feed
257 Nozzle array(s)
258 Mounting substrate
259 Mounting substrate passageway
262 Ink tank
263 Ink outlet port
265 Ink connection lines
300 Printer chassis
303 Print region
304 Media advance direction
305 Carriage scan direction
306 Wall
312 Feed roller
313 Forward rotation direction (of feed roller)
323 Passive roller(s)
324 Discharge roller
330 Maintenance station
332 Cap
371 Piece of recording medium
380 Carriage motor
382 Carriage guide rod
383 Encoder
384 Belt
390 Electronics board | A method of making an ink cartridge by forming an ink chamber, an air accumulation chamber, and a cap including a vent hole is disclosed. The cap is affixed at a first end of the air accumulation chamber and a one way valve is disposed at the vent hole for preventing gas from entering the air accumulation chamber through the vent hole when a pressure in the air accumulation chamber is less than a cracking pressure of the one-way valve. A neck region narrower than the ink chamber and the air accumulation chamber is formed for fluidically connecting the ink chamber and the air accumulation chamber. A mass is placed within the air accumulation chamber, the mass having a dimension smaller than an interior dimension of the air accumulation chamber such that the mass is movable between the first end and a second end of the air accumulation chamber. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority and benefit of U.S. Provisional Patent Application No. 60/622,693 filed Oct. 28, 2004 in the names of the same inventors, Michael J. Nigro and Karl A. Frederick, and entitled MOBILE AIR DUCT AND DRYER VENT CLEANING SYSTEM.
FIELD OF THE INVENTION
[0002] This invention relates generally to duct cleaning devices, and specifically to pneumatic duct cleaning devices.
STATEMENT REGARDING FEDERALLY FUNDED RESEARCH
[0003] This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government.
BACKGROUND OF THE INVENTION
[0004] In structures having ducts for ventilation systems, normal use causes dust and debris to accumulated within the ducts: dust, debris, skin flakes, skin and dust mites, hair, left over construction fibers, decaying matter, pollen, bacteria, dead insects, mold and many other types of foreign matter occur in the typical ventilation system, air duct, HVAC ducting, dryer vents and so on. Obviously, individuals exposed to air which passes through the ducts may well experience health issues as a result. In addition, a sufficient accumulation of such dust and debris may actually measurably degrade the efficiency of the airflow of the system and thus the energy efficiency of the furnace, dryer, air conditioner, evaporative (“swamp”) cooler, fans, etc which use the system. These various types of ducts may have differing sizes and geometries, but they share the problem of dust and debris accumulation.
[0005] Periodic cleaning of such systems is thus a necessity.
[0006] There are a variety of methods for the cleaning of such systems. One example is a system which utilizes a hose through which a flexible rotating cable is run with a brush coupled to the flexible rotating cable. A vacuum intake closely disposed to the brush entrains and carries off dust and debris dislodged by the action of the brush. Examples of such equipment include U.S. Pat. No. 4,792,363 issued Dec. 20, 1988 and U.S. Pat. No. 5,802,667 issued Sep. 8, 1998, the latter of which also has through holes in the length of the conduit, allowing additional entrainment of air sucked in along the length of the conduit, creating additional vacuum cleaning of the duct.
[0007] However, such systems have various disadvantages. In particular, the rotating cable (or drive shaft) may rub against the interior of the vacuum hose and possibly even break it. In addition, the mechanical rotation of flexible cables in a necessarily “lossy” process having high losses of mechanical energy to flexion, to torque being channeled into angles around which the cable passes and so on. The net result is a reduced mechanical efficiency as well as a reduced vacuuming efficiency of the vacuum hose, the latter caused by the rotating and twisting cable within.
[0008] Other devices known are quite complex or use multiple machines for carrying out the brushing/agitation and the vacuum processing. Such machines tend to be less portable, require routing cables, may restrict airflow, may be costly to manufacture or use, may require special training and so on.
[0009] It would be advantageous to provide a machine which is simple to manufacture, easy to use, portable, self contained and yet carried out the functions of operator controlled brushing and vacuuming.
[0010] It would further be advantageous to provide a machine which may be easily adapted to various different types of duct work.
SUMMARY OF THE INVENTION
[0011] General Summary
[0012] The present invention provides a mobile, self contained system and process for removing debris and dust from the interior of duct work without use of rotating shafts or cables.
[0013] Two major portions of the invention, a mobile housing and a vacuum head are connected by a flexible hose.
[0014] The mobile housing and equipment unit may have a plurality of wheels which can be easily removed. The housing and equipment unit may be light enough to be carried or rolled by hand grip on a handle. Within the housing a vacuum source, debris collection plenum, air compressor and associated structures are disposed. On the exterior of the housing, controls and an air hose attachment point may be located.
[0015] The vacuum head has an air hose attachment point, a turbine or other pneumatic drive, a vacuum intake, and a rotating brush powered by the turbine/pneumatic drive.
[0016] The flexible air hose connecting the housing and head is a “two way” hose having a first compressed air feed hose supplying compressed air from the compressor to the turbine, thus providing power to agitate or rotate the brush. A vacuum hose withdraws air from the vacuum head, thus entraining and removing debris and dust. A second compressed air feed line may supply compressed air to the turbine to drive the (reversible) turbine in the opposite direction. In alternative embodiments, reciprocating, radial or other types of pneumatic drives may be used to provide the mechanical motion of the brush, and the brush may be moved or agitated in more than one degree/dimension of motion.
[0017] Hoses, of course, are notably less expensive to manufacture than flexible drive cables or drive shafts, last longer, have no moving parts, do not rub, do not lose mechanical efficiency when they press up against a corner, and may easily be made to a length greater than the maximum length at which most drive cables can function.
SUMMARY IN REFERENCE TO CLAIMS
[0018] It is therefore a first aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus comprising:
a portable housing; a vacuum motor disposed within the portable housing, the vacuum motor providing vacuum to a vacuum hose coupling located on the portable housing; a flexible vacuum hose; the vacuum hose having a first end operatively connected to the vacuum hose coupling; the vacuum hose having a second end having a physical attachment to a pneumatic drive; a compressor motor disposed within the portable housing, the compressor motor operatively connected to a first compressed air feed line, the first compressed air feed line operatively connected to the pneumatic drive; the pneumatic drive operated by compressed air from the first compressed air feed line to produce a first degree of mechanical motion; and a brush physically connected to the pneumatic drive and mechanically moved such first degree of mechanical motion.
[0025] It is therefore a second aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus wherein the pneumatic drive further comprises:
a turbine operated by compressed air from the first compressed air feed line.
[0027] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus wherein the turbine further comprises:
a turbine shaft rotated by operation of the turbine, the brush attached to such turbine shaft whereby the first degree of mechanical motion of the brush is rotation in a first direction.
[0029] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus further comprising:
a second compressed air feed line operatively connected at a first end to the compressor motor and at a second end to the pneumatic drive.
[0031] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus wherein the pneumatic drive comprises a multiple motion drive capable of producing a second degree of mechanical motion when driven by the second compressed air line.
[0032] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus wherein the second degree of mechanical motion further comprises: rotation in a second direction different from the first direction.
[0033] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus wherein the first compressed air feed line is disposed within the vacuum hose.
[0034] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus further comprising: a vacuum nozzle physically attached to the second end of the vacuum hose.
[0035] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus wherein the nozzle further comprises the physical attachment of the second end of the vacuum hose to the pneumatic drive.
[0036] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus further comprising:
a debris collection plenum having a first operative vacuum connection to the vacuum supplied by the vacuum motor and having a second operative vacuum connection to the vacuum hose coupling, whereby air from the vacuum hose passes through the debris collection plenum before passing through the vacuum motor.
[0038] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a duct cleaning apparatus further comprising:
a HEPA rated filter disposed so that air exiting the debris collection plenum passes through the HEPA filter.
[0040] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a method of duct cleaning comprising the steps of:
a) physically attaching a brush to a pneumatic drive and operatively connecting a first end of a compressed air line to the pneumatic drive; b) inserting a first end of a vacuum hose into such duct; c) inserting the brush, pneumatic drive and first end of the compressed air line into such duct; d) providing vacuum to such vacuum hose; and e) providing compressed air to such compressed air feed line, whereby such pneumatic drive moves such brush.
[0046] It is therefore yet another aspect, advantage, objective and embodiment of the invention to provide a method of duct cleaning further comprising:
a1) physically attaching the vacuum hose to the pneumatic drive.
[0048] It is therefore yet another aspect, advantage, objective and embodiment of the invention to provide a method of duct cleaning further comprising:
a2) disposing the compressed air feed line within the vacuum hose.
[0050] It is therefore yet another aspect, advantage, objective and embodiment of the invention to provide a method of duct cleaning further comprising:
a3) providing a HEPA rated filter; and d1) filtering vacuumed air through the HEPA rated filter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] FIG. 1 is a partially cross-sectional diagram of a first vacuum head embodiment of the device, a presently preferred embodiment and best mode now contemplated for carrying out the invention.
[0054] FIG. 2 is a partially cross-sectional diagram of a second vacuum head embodiment of the device having only one compressed air feed line.
[0055] FIG. 3 is a side view of a third vacuum head embodiment of the device in which the compressed air feed line(s) are external to the vacuum hose.
[0056] FIG. 4 is a side view of a fourth equipment housing embodiment of the invention.
[0057] FIG. 5 is a partially cross sectional side view of a fifth equipment housing embodiment of the invention.
INDEX TO REFERENCE NUMERALS
[0000]
Brush 1
Turbine/pneumatic drive 2
Nozzle/turbine support 3
Brackets 4
First electrical cable 5
Second electrical cable 6
Hinged lid 7
First handle 8
Vacuum motor 9
Access lid 10
Filter 11
First wheel 12
First switch 13
Second switch 14
Air compressor 15
Output connector 16
Third compressed air feed line 17
Input valve connector 18
Output valve connector 19
Second compressed air feed line 20
First compressed air feed line 22
Forward output connector 23
Air valve 24
Air valve switch 25
Air seal 26
Vacuum inlet opening 27
Hose intake 28
Hose coupler 29
Vacuum hose 30
Second wheel 31
Debris collection plenum 32
Compressor plenum 33
Vacuum motor plenum 34
Housing 35
Vacuum chamber wall 36
DETAILED DESCRIPTION
[0093] FIG. 1 is a partially cross-sectional diagram of a first vacuum head embodiment of the device, a presently preferred embodiment and best mode now contemplated for carrying out the invention. Brush 1 may be of any suitable configuration for duct cleaning: round, elongated, etc, and may be a bristle brush or other stiff brush or may in embodiments be a softer brush or buffer, depending upon the nature of the duct interior and the debris and dust to be found in the duct.
[0094] Turbine/pneumatic drive 2 may advantageously be a turbine, however, the invention is not so limited. The pneumatic drive 2 may be a rotary device, a reciprocating device and so on. The pneumatic drive 2 may be operated by application of compressed air to produce mechanical motion of a shaft, chain or similar structure which may in turn power brush 1 to move. The range of degrees of motion is not limited: the brush may be moved in embodiments in three dimensions, two directions each, and in three axes of rotation, both forward and backward, and may also move in a combination of such degrees of motion. The pneumatic drive 2 may be reversible so that application of compressed air in one direction produces a first degree direction of motion while application of compressed air in another direction produces a second degree of motion in the opposite direction. In one preferred embodiment, pneumatic drive 2 may cause brush 1 to rotate, and by reversing the pneumatic drive 2 , the brush 1 may rotate in the opposite direction. In other embodiments, brush 1 may automatically agitate in different types of motion, for example, rotating while moving back and forth, based upon the design of pneumatic drive 2 .
[0095] Application of compressed air in different ways to pneumatic drive 2 may be produced by multiple compressed air feed lines 22 , 20 . First and second compressed air feed lines 22 , 20 may be controlled by valves located at the main equipment housing unit, allowing an operator or an automatic control device to easily change the motion of the brush 1 .
[0096] Vacuum hose 30 may be a standard hose of types commonly used in the industry or may be of a customized type. In the best modes now contemplated, the vacuum hose 30 may serve as the support and motive force for the entire vacuum head assembly: when the operator pushes vacuum hose 30 further into the duct, the entire head moves, drive, brush and all.
[0097] Nozzle/turbine support 3 may be either a vacuum nozzle or a support for the pneumatic drive or may serve both functions as in the preferred embodiment. Thus when vacuum hose 30 is urged deeper into the ductwork, pneumatic drive 2 and brush 1 will also be forced further into the ductwork. Brush 1 further serves the beneficial purpose of tending to keep vacuum hose 30 aligned near the centerline of the duct. Various geometries of nozzles and supports may be used.
[0098] Compressed air lines 22 , 20 may in the presently preferred embodiment be disposed within vacuum hose 30 , thus greatly reducing drag on the head as it is pushed into the duct and serving to protect the compressed air lines 22 , 20 and help prevent kinks in either the compressed air lines 22 , 20 or the vacuum hose 30 .
[0099] FIG. 2 is a partially cross-sectional diagram of a second vacuum head embodiment of the device having only one compressed air feed line. In this embodiment, the pneumatic drive 2 may be of a type which responds to fluctuations in pressure when altering the type of motion generated. For example, pneumatic drives are made which may sense a short cessation of compressed air and respond by automatically changing direction when the single air line resumes feeding air in the original direction. In alternative embodiments of reduced cost, the pneumatic drive 2 may simply always produce the same degree of motion (rotation in the clock-wise direction, for example, or back and forth agitation) and yet produce satisfactory cleaning of duct interiors. Thus reciprocating drives may be used.
[0100] FIG. 3 is a side view of a third vacuum head embodiment of the device in which the compressed air feed line(s) are external to the vacuum hose. This embodiment may provide for simpler manufacturing as it allows simpler construction of the housing, hose and air lines, however, the preferred embodiment is as discussed in reference to FIG. 1 .
[0101] As shown in FIG. 3 , turbine drives may be advantageously employed. The pneumatic drive, regardless of type, may be located in a variety of locations relative to the vacuum hose 30 : inside, outside, at the nozzle, projecting beyond the nozzle, or separated. The vent from the drive to the exterior may be disposed within the vacuum tube or without.
[0102] FIG. 4 is a side view of a fourth equipment housing embodiment of the invention. The exterior of the equipment housing has first and second electrical cables 5 , 6 . In practice, the device may be expected to be used in residential settings in which large amounts of drawn current may be unavailable. As both the vacuum and the air compressor draw large amounts of current, two cables may be preferable, allowing dispersion of the load over different circuits of a home, office, or small business. In addition, many air compressors and vacuums as used within the housing may have their own cords adapted for their own use (for example a 240 VAC cord for one item but a 120 VAC cord for the other) and so different cords may be more easily implemented or simply required.
[0103] Hinged lid 7 allows access to the interior of the housing 35 in one location while access lid 10 may allow access in another location. Access to the interior may be necessary to allow removal of debris collected, to change HEPA filters, for repairs and so on.
[0104] First handle 8 may be mounted so as to allow the device to be easily rolled (off center and elongated) or it may be mounted so as to allow for carrying in lighter versions of the device (above the center of gravity). In testing, the size of the unit has been found to be such that rolling in a manner analogous to a furniture dolly is usually preferable to hand carrying. Thus first wheel 12 may be large, making it easier to wheel the device over carpet, lintels, steps, stairs, lawn and the like. Second wheel 31 may be smaller. Any wheels of the device may be removable to allow easier hand carrying.
[0105] First switch 13 may control electrical supply from the cord 5 or 6 to vacuum, while second switch 14 may control electrical supply to the air compressor. One switch may be used for both functions, however, for flexibility of use two switches are desirable. In addition, the switches may be variable, allowing different degrees of vacuum or air compression as desirable.
[0106] Air valve switch 25 is not an electrical switch but a control valve determining which of the two compressed air feed lines receives compressed air. This valve and switch allow the operator to change from one type of brush motion to another type at the flip of a switch conveniently located on the equipment housing, right to hand for the operator. This may have an externally protruding portion allowing easy access for control, but the main valve body of the switch may be inside the housing 35 .
[0107] Housing 35 may be metal, wood, high strength polymer, composite or the like. It is structurally sound enough to withstand the weight of the compressor and vacuum inside it and the abuse of continuous relocation to new locations for duct cleaning. It is also air tight in portions, allowing the vacuum generated by the vacuum motor to suck debris into an internal plenum. It may have circulation vents to allow free air flow to other locations however, in particular, the vacuum motor and air compressor should have free air flow to them.
[0108] In alternative embodiments, housing 35 may in fact be eliminated. The air compressor and vacuum motor may be attached to a wheeled framework or the like instead.
[0109] FIG. 5 is a partially cross sectional side view of a fifth equipment housing embodiment of the invention.
[0110] Brackets 4 hold vacuum motor 9 onto vacuum chamber/debris collection plenum wall 36 . First electrical cable 5 and second electrical cable 6 provide electrical power as noted, penetrating through the housing 35 to the interior equipment.
[0111] Vacuum motor 9 may be a standard commercial vacuum motor or may be a custom design for the application. Filter 11 may serve several purposes: it may prevent damage to the vacuum motor from grit or objects entrained and brought into the debris collection plenum/vacuum chamber 32 . However, by providing a HEPA rated filter, the air exhausted from the device may be made cleaner than the air coming in, a sanitary measure and a safety measure.
[0112] Air compressor 15 may also be a standard air compressor as known in the art, or may be customized for the application. In practice, smaller air compressors are desirable for weight reasons, however, the air compressor 15 should be of a capacity to properly serve pneumatic drive 2 . Sound baffling of compressor plenum 33 may in embodiments be provided to help deal with the substantial noise of the air compressor, or a relatively quiet type of air compressor may be used. Such sound insulation should not interfere with the inflow of air to the compressor 15 .
[0113] Output connector 16 allows compressed air from compressor 15 to pass to third compressed air feed line 17 , which in turn is connected to input valve connector 18 of air valve 24 , the valve allowing compressed air feed to multiple different lines to the pneumatic drive via output valve connector 19 to second compressed air feed line 20 to first compressed air feed line 22 via forward output connector 23 . As commented, air valve switch 25 may be located on the outside of the equipment housing 35 for convenient use.
[0114] Air seal 26 allows the compressed air lines 22 , 20 to pass through into the debris collection plenum 32 without allowing air to pass into the chamber/plenum itself.
[0115] Vacuum inlet opening 27 provides access to the plenum 32 for air and entrained waste coming down vacuum hose 30 . The size of the chamber/plenum in comparison to the cross sectional area of the vacuum hose 30 means that air entering the plenum 32 immediately slows and reduces pressure. This has the desirable effect of cooling the air but the primary purpose is to cause the slower, thinner air to “drop” entrained particles and debris.
[0116] Hose intake 28 is the internal end of the conduit or flow path created by the vacuum hose 30 , it may be the same size as vacuum hose 30 in cross sectional area or it may be smaller or larger.
[0117] Hose coupler 29 allows easy attachment and removal of vacuum hose 30 along with associated compressed air lines 22 , 20 , thus greatly aiding portability and allowing interchange of different vacuum heads, hose lengths, hose diameters, hose materials, types of compressed air feed lines and the like.
[0118] Vacuum motor plenum 34 allows vacuum motor 9 to sit in a separate chamber from air compressor 15 , aiding the use of clean air for the compressor and cooled air for the vacuum motor 9 , and preventing potentially undesirable recirculation.
[0119] The disclosure is provided to allow practice of the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the appended claims. | A mobile, self contained system and process for removing debris and dust from the interior of ductwork without use of rotating shafts or cables. A mobile housing and equipment unit may have a plurality of wheels which can be easily removed. Within the housing a vacuum source, debris collection plenum, air compressor and associated structures are disposed. The vacuum head has an air hose attachment point, a turbine or other pneumatic drive, a vacuum intake, and a rotating brush powered by the turbine/pneumatic drive. A first compressed air feed hose supplies compressed air from the compressor to the turbine, thus providing power to agitate or rotate the brush. A vacuum hose withdraws air from the vacuum head, thus entraining and removing debris and dust. A second compressed air feed line may supply compressed air to the turbine to drive the (reversible) turbine in the opposite direction. | 5 |
FIELD OF THE INVENTION
This invention relates to urea-surfactant clathrates and their use in enhancing the microbial degradation of hydrocarbon contaminated soils and water.
BACKGROUND OF THE INVENTION
As is well known there are several microbial species found in soil and water that are capable of assimilating petroleum hydrocarbons. Unfortunately, the rate of microbial assimilation of petroleum hydrocarbons is relatively slow. It is necessary, therefore, to stimulate the microbial assimilation of petroleum hydrocarbons if bioremediation is to be utilized in removing such pollutants from soils and water.
In general, the rate and extent of microbial utilization of petroleum hydrocarbons is limited by the concentration of microbial nutrients and microflora available at the hydrocarbon water interface. Therefore, microbial nutrients, especially nitrogen containing nutrients like urea, have been added to contaminated soil or water as a method for enhancing the biodegradation of the petroleum contaminants. Because these nitrogen containing microbial nutrients are generally water soluble, and because the petroleum hydrocarbons are hydrophobic several different techniques have been used for delivering the nutrients to the hydrocarbon-water interface. For example, one technique employed is to coat the nutrients with a material such as petrolatum in an attempt to keep the nutrient at the hydrocarbon water interface. Another technique that has been employed is to deliver the nutrients in an aqueous solution along with a surfactant which aids in delivering the microbial nutrients to the hydrocarbon-water interface.
There are, of course, many other facets to the treatment of contaminated soils and water and many researchers have worked toward discovering more successful processes for improving biodegradation of contaminated soils and water.
It is the object of the present invention to provide novel compounds that have particular utility in enhancing microbial degradation of hydrocarbon contaminated soils and water.
It is another object of the present invention to provide compositions containing such novel compounds suitable for use in stimulating the propagation of naturally occurring, hydrocarbon assimilating, microflora to enhance the bioremedation of hydrocarbon contaminated soils and water.
SUMMARY OF THE INVENTION
Simply stated, one embodiment of the present invention provides novel compounds comprising an adduct of urea with a non-ionic surfactant.
In another embodiment of the present invention, there is provided a composition suitable for enhancing the biodegradation of contaminated soils, water and sludge which comprises at least one adduct of urea with a non-ionic surfactant, preferrably in combination with a phosphorous source.
These and other embodiments of the present invention will become more apparent upon reading the detailed description which follows.
DETAILED DESCRIPTION OF THE INVENTION
Novel compounds of the present invention are adducts or inclusion complexes of urea with a non-ionic surfactant, in which urea is the "host" and the surfactant is the "guest". In general, the weight ratio of urea to surfactant in the adduct will be in the range from about 98:2 to about 75:25, and preferably in the range from about 80:20 to about 76:14.
The non-ionic surfactant suitable in forming the novel compounds of the present invention are those surfactants which are capable of forming clathrates with urea. Non-limiting examples of such non-ionic surfactants are alkyl ethoxylated phosphates, alkyl ethyoxylated-amines, alkyl ethoxylated ammonium salts, alkyl ethyoxylated sugars and alkyl ethoxylated polyhydric alcohols and their cyclic ethers, such as sorbitol and sorbitan, in which the alkyl groups will have from about 8 to about 22 carbon atoms and in which the ethylene oxide groups will range from about 2 to 50 and may be monodispersed or polydispersed.
The adducts of the present invention can be readily synthesized by co-crystallizing urea and the surfactant from an appropriate solvent. Typical solvents used in the preparing the urea-surfactant adducts include alcohols such as methanol and mixed solvents such as methanol/isopropyl alcohol in volume ratios of about 80 to 20. Typically, the urea and surfactant are dissolved in the solvent at elevated temperatures, e.g., at about 50° C., and thereafter the solvent is allowed to evaporate slowly with the concommittant formation of crystals of the adduct.
Not wishing to be bound by any theory or mechanism it is believed that the novel surfactant-urea adducts of the present invention when contacted with water disassociate in such a fashion that at least some of the urea molecules stay associated with the head group of the surfactant thereby enhancing the delivery of the urea to the hydrocarbon-water interface where it is most needed for stimulating microbial growth and assimilation of hydrocarbon contaminants.
In any event, compositions for enhancing the biodegradation of hydrocarbon contaminated soils and water comprise at least one adduct of urea and a non-ionic surfactant. Preferably, the surfactant will be selected from those surfactants described above. Preferably the urea-surfactant adduct is combined with a phosphorous source. It is particularly preferred, however, that the urea surfactant clathrate be combined with the phosphorus source or other microbial nutrients to obtain a composition having a N:P ratio in the range of about 10:2 to about 10:0.5 and preferably about in the range 10:1. Such other microbial nutrients that can be added to the clathrate include ammonium hydrogen phosphate, sodium phosphate, and the like. In some instances, more than one adduct of urea and non-ionic surfactant can be successfully combined, for example, in equal amounts.
In addition to the urea-surfactant adduct and phosphorous source, optionally, the compositions may include other components such a salicylates to stimulate aromatic degradation and micro nutrients typically used in bioremediation processes.
Non-limiting examples of various compositions are given in Table 1 which follows.
TABLE 1______________________________________ Urea PhosphorousFormulation Surfactant/Wt. % Source/Wt. %______________________________________1 Urea-Oleyl-2-etboxylate/44% NH.sub.4 H.sub.2 PO.sub.4 /12% Urea-trilaurethphosphate/44%2 Urea-tetradecylammonium NH.sub.4 H.sub.2 PO.sub.4 /12% Urea-trilauretbphosphate/44%3 Urea-trilaurethphosphate/83.4% NH.sub.4 H.sub.2 PO.sub.4 /10.6% Sodium Salicylate/6%______________________________________
In treating contaminated soil and water in accordance with the present invention, the urea-surfactant composition is applied to the soil or water by broadcasting in an amount sufficient to enhance the rate of biodegradation of the contaminated soil and water. The amount applied can vary broadly and typically will depend upon the weight percent of hydrocarbon contaminant on the soil or water. Preferrably, the amount of the urea-surfactant formulation will be applied in an amount sufficient to provide a C:N:P ratio of from about 100:10:1 to about 100:1:0.1.
When treating contaminated soil with compositions of the present invention, it is generally preferred to maintain the moisture content of the hydrocarbon contaminated soil at from about 10 wt. % to 35 wt. %.
The following examples will more fully illustrate the invention.
EXAMPLES 1-10
These examples demonstrate the preparation of the novel urea non-ionic surfactant adducts of the present invention.
To 20 gm. of methanol was added 5 gm. of urea and 1 gm. of the surfactant shown in Table 2. The mixture was heated until the urea and surfactant both dissolved. After cooling to room temperature, the solvent was allowed to evaporate very slowly and the urea-surfactant clathrate crystals formed were separated by filtration, washed with cold methanol and dried. The weight ratio of urea to surfactant for each composition prepared is given in Table 2.
TABLE 2__________________________________________________________________________Surfactant Wt. %Commercial Urea/ExampleName Nominal Formula Surfactant__________________________________________________________________________1 Neodol 91-8.sup.1 C.sub.10 H.sub.21 (OCH.sub.2 CH.sub.2).sub.8 OH 83/172 Neodol 91-8.sup.1 C.sub.10 H.sub.21 (OCH.sub.2 CH.sub.2).sub.8 OH 90/103 Neodol 91-8.sup.1 C.sub.10 H.sub.21 (OCH.sub.2 CH.sub.2).sub.8 OH 95/54 Brij-92.sup.2 C.sub.18 H.sub.35 (OCH.sub.2 CH.sub.2).sub.2 OH 83/175 Trilaureth (C.sub.12 H25(OCH.sub.2 CH.sub.2).sub.4 O).sub.3 PO 83/17Phosphate6 Tween-80.sup.3 C.sub.18 H.sub.35 CO.sub.2 -Sorbitan-(OCH.sub.2 CH.sub.2).sub. 10 OH 83/177 Span-80.sup.4 C.sub.18 H.sub.35 CO.sub.2 -Sorbitan 83/178 Span-20.sup.4 C.sub.12 H.sub.25 CO.sub.2 -Sorbitan 83/179 E-14-5 Ethoxylated Amine.sup.5 ##STR1## 83/1710 E-14-5 Ethoxylated Ammonium Salicylate ##STR2## 83/17__________________________________________________________________________ .sup.1 Neodol 918 is the tradename for an ethoxylated alcohol sold by Shell Chemical Company, Houston, TX. .sup.2 Brij92 is the tradename for an ethoxylated alcohol sold by ICI America's, Inc., Wilmington, DE. .sup.3 Tween80 is the tradename of an ethoxylated Sorbitan ester sold by ICI American's Inc., Wilmington, DE. .sup.4 Span 80 and Span 20 are tradenames of Sorbitan esters sold by ICI Americas Inc., Wilmington, DE. .sup.5 E14-5 ethoxylated amine is the tradename of an ethoxylated amine sold by Exxon Chemical Company, Houston, TX.
EXAMPLES 11-12
In these two examples, Formulations 1 and 2 of Table 1 were prepared and tested in the biodegradation of refinery soil. The N:P ratio of the formulations were 10:1.
The tests were conducted as follows. A refinery soil having weathered hydrocarbon contaminants was used which had approximately one weight percent contaminant as determined by EPA Method 418.1. To three separate polypropylene pans, 12 inches long, by 8 inches wide and 3 inches deep, 2,000 gms of the hydrocarbon contained contaminated soil were added. Two of the pans were treated by uniformly broadcasting the urea-surfactant formulation onto the soil surface to provide a C:N:P of 100:10:1. The soil in the pans were watered and hand-tilled weekly. The amount of water applied was sufficient to provide a moisture content of about 17 wt. %. After 8 weeks, the percent petroleum hydrocarbon biodegraded was determined for each of the samples using the EPA Method 418.1 with the following modifications.
1) The soil sample size was increased to 30 grams.
2) The acidification step specified in the test was eliminated.
3) The drying agent used was magnesium sulfate.
4) The amount of drying agent required by the test was increased to assure effective drying.
5) A four hour time period for soxhlet extraction was employed.
6) The amount of silica gel used in the final filtration step was increased.
The microbial population was determined on the soil samples 2 weeks after treatment. The standard most probable number (MPN) microbioloy method was employed and a two week incubation period was allowed. The results of these tests are shown in Table 3.
Additionally, one pan, a control pan, containing untreated soil was watered, hand tilled and subjected to the same tests outlined above. In this instance the control is labeled Comparative Example 1 and the results for it are also given in Table 3.
TABLE 3______________________________________ % Hydrocarbon Microbial Biodegraded PopulationExample Formulation In 8 Weeks MPN Heterotrophs______________________________________11 1 22 7.5 E + 6412 2 20 8.6 E + 04Comparative 1 -- 2 1.7 E + 02______________________________________
The formulations 1-3 listed in Table 1 were also tested using a refinery landfarm soil sludge. In these tests, three kilograms of a refinery landfarm sludge sieved to contain soil particles less than 2 mm in size was added to an oily refinery sludge so that the effective hydrocarbon contaminate on the soil was 2.5 wt. %.
Five polypropylene pans with the same dimensions as outlined in Examples 11 to 12, each containing 3 kilograms of soil were set up and treated with the formulations as shown in the Table 4. To three of the pans the solid formulations were broadcast onto the surface with periodic tilling and mixing of the soil sludge.
The fourth pan was treated with granular urea and sodium phosphate (combined to provide a C:N:P ratio of 100:10:1.) This is labeled Comparative Example 2. In Table 4, the fifth pan was untreated but otherwise watered, hand tilled and tested. The result of the control pan labeled Comparative Example 3 in Table 4.
As indicated, all the pans were watered and tilled three times per week. The percent hydrocarbon that biodegraded was determined by the modified by the EPA 418.1 Test Method outlined above for each pan every two weeks for 9 weeks. From the time versus percent biodegraded data pseudo first order rate constants were determined for each treatment. These results are presented in Table 4.
TABLE 4______________________________________ % Hydrocarbon Pseudo First Degraded in Order RateExample Formulation 9 Weeks Constant (1/days)______________________________________13 1 18 1.14 E - 0314 2 17 2.33 E - 0315 3 31 4.21 E - 03Comparative 2 -- 7 4.21 E - 05Comparative 3 -- 0 --______________________________________
It should be readily appreciated that the foregoing Examples are not intended to be limiting but merely intended to be illustrative of the mechanisms and materials pertaining to the invention. | One embodiment of the present invention provides compounds comprising an adduct of urea with a non-ionic surfactant. Another embodiment of the present invention, there is provided a composition suitable for enhancing the bioremediation of contaminated soils and water which comprises at least one adduct of urea with a non-ionic surfactant, preferably in combination with a phosphorous source. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a suspension apparatus to be used for suspending a truck-type circuit breaker or the like when the circuit breaker is put on or taken off of the truck of a switchboard frame.
2. Description of the Prior Art
A conventional suspension apparatus, which is to be used for suspending a truck-type circuit breaker or the like, is described referring to FIGS. 6 and 7. FIG. 6 is a perspective view for showing the truck-type circuit breaker or the like which is suspended by a conventional suspension apparatus. FIG. 7 is a partial sectional side view showing the constitution of a hook part taken along line VII--VII in FIG. 6.
As is obvious from the figures, a pair of hollows 2 are provided on both side faces of a truck-type circuit breaker 1. As shown in FIG. 7, each hollow 2 is overhanged toward the bottom of the circuit breaker. A pair of suspension adapters 3, which have a substantially J-shaped section, are respectively engaged with the hollows 2 from below. Each suspension adapter 3 has a hole 4, so that a rope or wire 5 is tied to the adapter 3 through the hole 4.
For suspending the circuit breaker 1 by the conventional suspension apparatus, once the circuit breaker 1 is put on a truck of a switchboard frame or a floor, the rope or wire 5 is loosened, and thereby, the suspension adapters 3 are disengaged from the hollows 2 of the circuit breaker 1. Therefore, disengaged suspension adapters 3 have to be re-engaged with the hollows 2 for re-suspending the circuit breaker 1.
SUMMARY OF THE INVENTION
The purpose of the present invention is to solve the above-mentioned problems and to provide an improved suspension apparatus wherein the suspension adapters may not be disengaged from the hollows of the object to be suspended even when the rope or wire which is tied to the suspension adapters is loosened.
A suspension apparatus in accordance with the present invention comprises:
a pair of first hollows respectively provided on both side faces of an object to be suspended;
a pair of second hollows respectively provided on an upper face of the object in the vicinity of both boundaries between a top face and the side faces of the object;
a pair of suspension adapters each having a hook to be engaged with the first hollow provided at an end thereof and means for trying a rope or wire being tied in the vicinity of the end; and
a pair of stoppers respectively provided on the suspension adapter for engaging with the second hollow.
When the suspension adapters are engaged with the first hollows of the object to be suspended, the stopper means such as hooks or plate springs are respectively engaged with the second hollows. Therefore, even when the rope or wire is loosened, the suspension adapters are firmly coupled to the object.
While the novel features of the invention are set forth particularly in the appended claims, the invention, both as to organization and content, will be better understood and appreciated, along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a suspension of an object by using a first embodiment of a suspension apparatus in accordance with the present invention.
FIG. 2 is a partial sectional side view showing a constitution of the first embodiment of the suspension apparatus.
FIG. 3 is a front view of the first embodiment of the suspension apparatus.
FIG. 4 is a perspective view showing a suspension of an object by using a second embodiment of a suspension apparatus in accordance with the present invention.
FIG. 5 is a partial sectional side view showing a constitution of the second embodiment of the suspension apparatus.
FIG. 6 is a perspective view showing the suspension of the object by the conventional suspension apparatus.
FIG. 7 is a partial sectional side view showing the constitution of the conventional suspension apparatus.
It will be recognized that some or all of the Figures are schematic representations for purposes of illustration and do not necessarily depict the actual relative sizes or locations of the elements shown.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first preferred embodiment of a suspension apparatus in accordance with the present invention is described referring to FIGS. 1, 2 and 3. FIG. 1 is a perspective view showing a suspension of an object by using the first embodiment of the suspension apparatus in accordance with the present invention. FIG. 2 is a partial sectional side view taken along line II--II of FIG. 1. FIG. 3 is a front view of the first embodiment of the suspension apparatus which is seen from a direction shown by arrow III in FIG. 1. Elements designated by the same numerals as those of the conventional suspension apparatus are substantially the same.
As is obvious from FIG. 1, a pair of first hollows 2 are provided on both side faces 1a of a truck-type circuit breaker 1. As shown in FIG. 2, each first hollow 2 is formed by an overhang from a side face over the bottom of the circuit breaker. A pair of suspension adapters 3, which have a substantially J-shaped cross-section, are respectively engaged with the hollows 2 from below. As shown in FIG. 3, each suspension adapter 3 has a hole 4, so that a rope or wire 5 is tied to the adapter 3 through the hole 4. As is also obvious from FIG. 1, a pair of second hollows 6 are provided on the upper face in the vicinity of the boundaries between the side faces 1a and a top face 1b of the circuit breaker 1. A stopper 7, which is substantially a hook lever, is rotatably held so as to cradle around a pivot 8 on each suspension adapter 3. The stopper 7 has a hook 7a which is to be engaged with the second hollow 6 of the circuit breaker 1. Furthermore, the stopper 7 has another hook 7c which is to be engaged with the suspension adapter 3 and a flat part 7b.
As shown in FIGS. 1, 2 and 3, when the suspension adapter 3 is engaged with the first hollow 2 and the hook 7a of the stopper 7 is also engaged with the second hollow 6 of the circuit breaker 1, the suspension adapter 3 is firmly coupled with the circuit breaker 1. Therefore, even when the rope or wire 5 is loosened, the suspension adapter 3 is not detachable from the circuit breaker 1.
For detaching the suspension adapter 3 from the circuit breaker 1, the stopper 7 is manually rotated, for example, in a counterclockwise direction in FIG. 3, and thereby, the hook 7a is disengaged from the hollow 6 of the circuit breaker. The suspension adapter 3 falls by gravity when the rope or wire 5 is loosened, similarly to the conventional suspension apparatus.
A second preferred embodiment of a suspension apparatus in accordance with the present invention is described referring to FIGS. 4 and 5. FIG. 4 is a perspective view showing suspension of an object by using the second embodiment of the suspension apparatus in accordance with the present invention. FIG. 5 is a partial sectional side view showing a constitution of the second embodiment. Elements designated by the same numerals as that of the above-mentioned first embodiment of the suspension apparatus are substantially the same, so that further explanation of them is omitted.
As shown in FIGS. 4 and 5, a stopper 9, which is made of a resilient material and has a substantially L-shaped cross-section, is fixedly mounted on the suspension adapter 3 in a manner that a protrusion 9a of the stopper 9 is to be engaged with the second hollow 6 of the circuit breaker 1.
As shown in FIG. 5, when the suspension adapter 3 is engaged with the first hollow 2 and the protrusion 9a of the stopper 9 is also engaged with the second hollow 6 of the circuit breaker 1, the suspension adapter 3 is firmly coupled with the circuit breaker 1. Therefore, even when the rope or wire 5 is loosened, the suspension adapter 3 is not detachable from the circuit breaker 1. For detaching the suspension adapter 3 from the circuit breaker 1, the suspension adapter 3 with stopper 9 is forcibly rotated, for example, in a clockwise direction in FIG. 5, and thereby, the protrusion 9a of the stopper 9 is disengaged from the hollow 6 of the circuit breaker. The suspension adapter 3 then falls by gravity when the rope or wire 5 is loosened, similarly to the above-mentioned first embodiment.
Although the present invention has been described in terms of the presently preferred embodiments, it is to be understood that such disclosure is not to be interpreted as limiting. Various alterations and modifications will no doubt become apparent to those skilled in the art after having read the above disclosure. Accordingly, it is intended that the appended claims be interpreted as covering all alterations and modifications as fall within the true spirit and scope of the invention. | A suspension apparatus for suspending a truck-type circuit breaker or the like when the circuit breaker is put on or taken off a truck of a switchboard frame comprises a suspension adapter to be engaged with a first hollow provided on a side face of the circuit breaker and a stopper provided on the suspension adapter to be engaged with a second hollow provided on a top face of the circuit breaker. | 1 |
This is a continuation of application No. 08/314,439, filed Sept. 28, 1994 now U.S. Pat. No. 5,502,273, which is a File Wrapper Continuation of Application No. 08/171,370 filed Jan. 14, 1994, abandoned, which is a File Wrapper Continuation of application No. 07/873,429, filed Apr. 24, 1992, abandoned.
This invention relates to the production of polyhydroxyalkanoate in plants.
Poly-3-hydroxybutyrate (PHAS) is a linear polyester of D(-)-3-hydroxybutyrate. It was first discovered in Bacillus natarium in 1925. Polyhydroxybutyrate accumulates in intracellular granules of a wide variety of bacteria. The granules appear to be membrane bound and can be stained with Sudan Black dye. The polymer is produced under conditions of nutrient limitation and acts as a reserve of carbon and energy. The molecular weight of the polyhydroxybutyrate varies from around 50,000 to greater than 1,000,000, depending on the micro-organisms involved, the conditions of growth, and the method employed for extraction of the polyhydroxybutyrate. Polyhydroxybutyrate is an ideal carbon reserve as it exists in the cell in a highly reduced state, (it is virtually insoluble), and exerts negligible osmotic pressure.
Polyhydroxybutyrate and related polyhydroxy-alkanoates, such as poly-3-hydroxyvalerate and poly-3-hydroxyoctanoate, are biodegradable thermoplastics of considerable commercial importance.
The terms “polyhydroxyalkanoate” and “PHA” as used hereinafter include polymers of 3-hydroxybutyrate, polymers of related hydroxyalkanoates such as3-hydroxyvalerate, 3-hydroxyhexanoate, 3-hydroxyoctanoate, 3-hydroxydecanoate, and also copolymers and mixtures of more than one of these hydroxy-alkanoates.
Polyhydroxyalkanoate is biodegradable and Is broken down rapidly by soil micro-organisms. It is thermoplastic (it melts at 180° C.) and can readily be moulded into diverse forms using technology well-established for the other thermoplastics materials such as high-density polyethylene which melts at around the same temperature (190° C.). The material is ideal for the production of biodegradable packaging which will degrade in landfill sites and sewage farms. The polymer is biocompatible, as well as biodegradable, and is well tolerated by the mammalian, including human, body; its degradation product, 3-hydrcxybutyrate, is a normal mammalian metabolite. Polyhydroxy-butyrate degrades only slowly in the body making it suitable for medical applications where long term degradation is required.
Polyhydroxyalkanoate, produced by the micro-organism Alcaligenes eutrophus , is manufactured, as a copolymer of polyhydroxy-butyrate and polyhydroxyvalerate, by Imperial Chemical Industries PLC and sold under the Trade Mark BIOPOL. The nature of the polymer, for example the proportions of PHB and PHV is determined by the substrate supplied in the fermentation. It is normally supplied in the form of pellets for thermoprocessing. However, polyhydroxyalkanoate is more expensive to manufacture by existing methods than, say, polyethylene. It is, therefore, desirable that new, more economic production of polyhydroxy-alkanoate be provided.
SUMMARY OF THE INVENTION
An object of the present invention is to provide materials and a method for the efficient production of polyhydroxyalkanoate.
According to the present invention there is provided a plant adapted for the production of polyhydroxyalkanoate comprising a recombinant genome of an oil-producing plant, which genome contains genes encoding enzymes necessary for catalyzing the production of polyhydroxy-alkanoate together with gene regulatory sequences directing expression of the said genes to target plant call components.
These regulatory sequences include promoter sequences directing expression of the biosynthetic pathway specifically to the developing seed, and transit peptide sequences targeting the enzymes to appropriate subcellular compartments.
The genes encoding the enzyme or enzymes necessary for the catalysis of polyhydroxyalkanoate production may be isolated from a micro-organism, such as Alcaligenes eutrophus , which is known to produce polyhydroxybutyrate and other polyhydroxy-alkanoates.
It is preferable, for reasons which will later be explained, that the plant be of a species which produces substantial quantities of oil, rather than starch. such plant species are well known and are simply referred to as “oil-seed” crops and include, oilseed rape, canola, soya and sunflower. Methods for the genetic transformation of many oil crops are known; for example, transformation by Agrobacterium tumefaciens methods are suitable for most. Such methods are well-described in the literature and well-known and extensively practised in the art.
The biosynthesis of polyhydroxybutyrate from the substrate, acetyl-CoA involves three enzyme-catalysed steps, illustrated in FIG. 1 herewith.
The three enzymes involved are β-ketothiolase, NADP linked acetoacetyl-CoA reductase, and polyhydroxybutyrate synthase, the genes for which have been cloned from Alcaligenes eutrophus (Schubert et al, 1988, J Bacteriol, 170). When cloned into Escherichia coli the three genes are known to facilitate production of polyhydroxyalkanoate up to 30% of the cell weight.
Genes specifying the production of alkanoates higher than the butyrate are known to exist in bacteria. Isolation of the appropriate genes allows expression of these higher polyhydroxy-alkanoates. For example, genes specifying production of the polyhydroxy-octanoate and the —decanoate exist in the bacterial species Pseudomonas oleovorans and Pseudomonas eruginosa . Howeverr genes for analogous polymers are widespread in bacterial species.
All the microorganisms required for performance of this invention are publicly available from public culture collections.
An important preferred feature of this invention is the use of an oilseed plant for expression of the polyhydroxyalkanoate. The reason behind our selection of oil-producing crops is that such plants naturally produce large amounts of acetyl-CoA substrate (under aerobic conditions) in the developing seed, which is normally used in fatty acid synthesis. Diversion of this substrate into polyhydroxyalkanoate production will reduce the amount of oil stored by the seed but will have minimal influence on other aspects of the cell's metabolism. It is therefore possible to produce commercial viable quantities of polyhydroxy-alkanoate such as polyhydroxybutyrate in an oilseed.
It has been previously suggested that Alcaligenes eutrophus genes could be expressed in a starch crop but this has certain problems. In order to optimise polyhydroxyalkanoate production in such a crop, it would probably be necessary to down-regulate starch synthesis. However, even if this down-regulation were to be effected it would not guarantee an increased rate of acetyl-CoA production. Moreover, even if this increased production were actually achieved, it is possible that the acetyl-COA would be rapidly utilised by respiration in the starch crop.
For expression in higher plants the bacterial (for example Alcaligene eutrophus ) genes require suitable promoter and terminator sequences. various promoters/torminators are available for use. For constitutive expression the cauliflower mosaic virus CaMV35S promoter and nos terminator may be used. It is however preferred to target synthesis of polyhydroxyalkanoate only to the developing oil storage organ of the oilseed such as the embryo of oilseed rape. The promoter of the rape seed storage protein, napin, could be used to obtain embryo specific expression of polyhydroxyalkanoate genes. Expression of the polyhydroxyalkanoate genes during the precise period when lipid is being made will ensure effective omrpetition by the polyhydroxyalkanoate enzymes for available acetyl-CoA. The promoters of fatty acid synthesis genes whose expressions are switched on at this time are thus most appropriate candidates to be used as polyhydroxyalkanoate gene promoters. Examples of such promoters are those of seed specific isoforms of rape acyl carrier protein (ACP) or β-ketoacyl ACP reductase.
In inserting the polyhydroxyalkanoate genes into eukaryotic cells, consideration has to be given to the most appropriate subcellular compartment in which to locate the enzymes. Two factors are important: the site of production of the acetyl-CoA substrate, and the available space for storage of the polyhydroxyalkanoate polymer.
The acetyl-CoA required for fatty acid synthesis in, for example, developing rapeseed embryo is produced by two routes. The first, direct, route involves the activity of a pyruvate dehydrogenase enzyme located in the plastid. The second route involves the initial production of acetyl-CoA by mitochondrial pyruvate dehydrogenase, lysis to free acetate, and diffusion of the acetate into the plastid where it is re-esterified to CoA by acetyl-CoA synthase. Rapeseed also produces acetyl-CoA in the cytosol, though at a lower rate than in the plastid, via the activity of a cytosolic citrate lyase enzyme.
Considering substrate supply, the bacterial (for example, Alcaligenes ) β-ketothiolase enzyme may function in the mitochondrion, using acetyl-CoA produced in excess of the requirements of respiration, or in the cytosol. The regulatory sequences of the invention may thus direct expression of the β-ketothiolase gene to the mitochondrion or to the cytosol. It is however preferred to target this enzyme to the plastids, where highest rates of acetyl-CoA generation occur.
The mitochandrion lacks sufficient space for storage of the polyhydroxyalkanoate polymer. Significant storage space exists in the plaitids, at least in rape embryo. Highest storage space exists in the cytosol, the compartment normally occupied by the oil bodies.
It is not known whether the acetcacetyl-CoA or hydroxybutyryl-CoA pathway intermediates can be transported from plastid to cytosol. Certainly they would not be able to traverse the plastid envelope membrane as CoA esters. Export would require that the acetoacetate or hydroxybutyrate groups are recognised by the transport systems involved in export of fatty acids from plastids. These have been suggested to involve: lysis of the CoA ester, export of the free acid, and resynthesis of the CoA ester in the cytosol; or transfer of the acyl groups to carnitine, and export of acyl carnitine. if acetoacetyl groups may be exported from the plastid by one of these mechanisms then it would be possible to target β-ketothiolase to the plastid, to utilise acetyl-CoA destined for lipid synthesis, and target acetoacetyl-CoA reductase and polyhydroxybutyrate synthase to the cytosol to achieve polymer synthesis in thie more spacious compartment. If neither acetoacetate nor hydroxybutyrate groups may be exported from the plastid, polyhydroxyalkanoate synthesis will require that all three pathway enzymes are targeted to this organelle so that they are expressed in the same cell compartment.
To target the three bacterial (such as Alcaligenes eutrophus ) enzymes for polyhydroxyalkanoate synthesis to the plant plastid requires the use of specific targeting regulatory elements called transit peptides. Possible sources of plastid stroma targeting sequences are the genes for:
(a) ribulose bisphosphate carboxylase/oxygenase small subunit (RUBISCO ssu);
(b) acyl carrier protein (ACP);
(c) β-ketoacyl ACP reductase;
(d) enolpyruvylshikimate-3-phosphate synthase (EPSPS);
(e) fructose 1,6-bisphosphatase.
Of these the RUBISCO small subunit transit peptide has been shown to direct polypeptides to plastids in both photosynthetic and non-photosynthetic tissues. ACP and β-ketoacyl ACP reductase transit peptides would also operate effectively in plants such as rape embryo. The advantage of using the same plastid transit peptide for all three polyhydroxyalkanoate genes is to ensure that any variability in the uptake of the genes is not due to the transit peptide which is used.
Although some proteins appear to be efficiently targeted to the plastid stroma by the transit peptide alone, other proteins also require the presence of up to twenty amino acids of the amino terminus of the mature protein. The requirement for the presence of mature sequences appears to depend on the size and charge of the protein to be transported.
To obtain synthesis of polyhydroxyalkanoate polymer in plant tissues it is necessary to obtain plants expressing all three genes for the enzymes β-ketothiolass, acetoacetyl-CoA reductase and polyhydroxybutyrate synthase. This may be achieved by using one of the following strategies:
i) Plants may be individually transformed with the three polyhydroxyalkanoate pathway genes. Plants containing individual genes are grown up in the glass-house and cross-pollinated to obtain hybrid plants containing two pathway genes. This procedure is then repeated to produce hybrid plants containing all three genes.
ii) Plants may be sequentially transformed with plasmids containing the individual pathway genes.
iii) Two or three pathway genes may be cotransformed into the same plant by simultaneous infection with Agrob.cteria containing the individual genes.
iv) Plants may be transformed with plasmids containing two or three pathway genes.
A combination of these techniques may be used to obtain expression of all three genes in a single plant. successive round of cross-pollination are carried out until the progeny are homozygous for all three genes. For methods (ii) and (iii) above, it is advantageous to insert each gene into vectors containing different selectable marker genes to facilitate selection of plants containing two or three polyhydroxyalkanoate pathway genes. Examples of selectable markers are genes conferring resistances to kanamycin, hygromycin, sulphonamides and bialaphos or phosphinothricin.
The invention will now be described by way of example only with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the pathway for polyhydroxybutyrate production in Alcaligenes eutrophus;
FIGS. 2A and 2B are a physical map of the 5.2 kb SmaIEcoRI fragment of Alcaligenes eutrophus DNA;
FIG. 3 is a map of the plant expression vector pJR1i;
FIG. 4 is a graph of β-ketothiolase enzyme activities in tobacco leaves;
FIG. 5 is a graph of NADP acetoacetyl CoA reductase enzyme activities in tobacco leaves.
DETAILED DESCRIPTION OF THE INVENTION
A 5.2 kb SmaI-EcoRI fragment which codes for all three polyhydroxyalkanoate (PHA) biosynthetic genes had previously been isolated from Alcaligenes eutrephus (Schubert et al, 1988 , J Bacteriol, 170). This fragment cloned into the vector pUC9 (New England Biolabs) together with a 2.3 kb PstI sub fragment cloned into Bluescript KS- (Stratagene) were provided by Dr Steinbuchel of the University of Gottingen, Germany. A restriction map of the fragment is shown in FIG. 2 . The positions of the restriction sites and the positions of the genes for β-katothiolase, acetoacetyl CoA reductase, and polyhydroxybutyrate (PHB) synthase are shown.
The expression vector chosen to gain constitutive expression of PHA biosynthetic genes in tobacco and oilseed rape plants was pJR1i. This vector contains the cauliflower mosaic virus CaMV35AB promoter and the nos terminator, separated by a multiple cloning site to allow the insertion of the PHA genes. The vector also contains the kanamiycin resistance npt II gene as a selectable marker. FIG. 3 is a map of the plant expression vector pJR1i. Vector pJR1Ri was also utilised; this vector contains the expression cassette in the opposite orientation.
All routine molecular biological techniques were those of Sambrook et al (1989, A laboratory manual, Second edition). Oligonucleotides were all synthesised on an Applied Biosystems 380B DNA Synthesiser. PCR machines used were Techne PHC-1 Programmable Dri-Blocks. Taq polymerase was obtained from Perkin-Elmer/Cetus. Restriction enzymes and other modifying enzymes were obtained from New England Biolabs, Gibco/BRL, Northumbria Biologicals Limited and Pharmacia. Sequencing kits were obtained from Cambridge Biosciences (Sequenase) and Promega (Taqtrack). All radio-isotopes were supplied by Amersham International.
1. Construction of vectors to gain constitutive cytosolic eAxpression of PHA pathway genes.
1.1. β-ketothiolase
The β-ketothiolase gene was isolated as a 1.3 kb PstI-PleI fragment from the 2.3 kb Psti fragment of pKS-::2.3P7. This fragment was blunt-ended with Klenow and was inserted into the dephosphorylated SmaI site of pJRIi. The resulting plasmid was denoted pJR1iT. Recombinant plasmids were identified by colony hybridisation using the 1.3 kb insert fragment as a probe. Restriction mapping of recombinants revealed those containing a single β-ketothiolase insert in the sense orientation. The orientation of the insert was confirmed by sequencing using a primer that hybridised to the 3′ end of the CaAMV35S promoter.
1.2. AAcotyoacetyl-CoAA reductase
The acetoacetyl-CoA reductase gene was isolated as a 0.9 kb AvaII-XmnII fragment from pKS ::2.3P7. This fragment was inserted into pJRIi as described for pRJIiT. However, the orientation of the insert fragment in recombinant plasaids could not be confirmed by restriction mapping due to the unavailability of suitable restriction enzyme sites. Therefore four recombinants were sequenced using the CaMV35S 3′ primer and, of these, one was found to contain a sense insert. This plasmid was denoted pJPi1iR.
1.3. PHB synthase
The PHB synthase gene was isolated from pKS::2.3P7 as a BstBI-StuI fragment. This fragment was blunt-ended and inserted into pJRIi as described for pJRIiT and pJRIiR. The identity of recombinant (pJRIiS) plasmids containing a single insert in the sense orientation was confirmed by restriction mapping and by sequencing with the CaMV35S 3′ primer.
2. Construction of vectors for constitutive plastid targeted expression of PHA pathway enzymes
Transport into plastids of the component polypeptides for each of the PHB pathway enzymes can be achieved by addition of a transit peptide sequence to the 5′ end of the gene sequence.
The first gene to be tailored was ketothiolase. A technique involving polymerase chain reaction (PCR) was employed in order to join the pea RUBISCO small subunit transit peptide sequence in frame with the ketothiolase gene.
Linking the transit peptide to the ketothiolase gene involved three experiments. The first experiment added a small portion of the 5′ end of the ketothiolase gene onto the 3′ end of the transit peptide sequence. The second experiment added a small portion of the 3′ end of the transit peptide onto the 5′ end of ketothiolase gene. The third experiment utilised the overhangs produced in the preceding experiments to extend across the junction and produce full length transit peptide linked in frame with the ketothiolase gene. Four PCR priuers were designed:
1. 5′ end of the transit peptide allowing extension toward its 3′ end (SEQ ID NO: 1):
AAA TGG CTT CTA TGA TAT CCT CTT CAG CT
TPI
2. 3′ end of transit peptlde linked to 5′ end of ketothiolase gene allowing extension toward 5′ end of transit peptide (SEQ ID NO: 2):
ACG ATG ACA ACG TCA GTC ATG CAC TTT ACT CTT CCA CCA TTG CTAT GT
TPKB
3. 3′ end of transit peptide linked to 5′ end of ketothiolase gene allowing extension toward the 3′ end of the ketothiolase gene (SEQ ID NO: 3):
ATT ACA AGC AAT GGT GGA AGA GTA AAG TGC ATG ACT GAC GTT ATC GT
TAPKT
4. 3′ end of ketothiolase gene (SEQ ID NO: 4):
ACC CCT TCC TTA TTT GCG CTC GAC T
K1
For the first experiment template DNA was pSM64 (transit peptide sequence) and the primers were TP1 and TPKB with an annealing temperature of 65° C. The derived PCR products were run out on an agarose gel and the band corresponding to 199 bp cut out and electroeluted from the gel.
In the second experiment template DNA was pKS::2.3P7, the primers involved were TPKT and K1 and the annealing temperature 68° C. The products of the PCR reaction were again run out on a gel and the required 1.207 kb band isolated and electroeluted from the gel slice.
The third experiment utilised the DNA isolated from the previous experiment as template and the primers TP1 and K1. The annealing temperature was 65° C. and although this PCR experiment was very inefficient some full length product (1.352 kb) was formed.
A small portion of each of the three PCR products was run out on an agarose gel. Southern blot analysis using three of the oligos as probes (TP1, K1 and TPKT) was carried out. Results are given in FIG. 4 and show that the product of the third reaction contained the 5′ end of the transit peptide, the overlap of 3′ transit peptide and 5′ ketothiolase gene, and the 3′ end of the ketothiolase gene.
It was necessary to check the sequence of this product as it is known that PCR can incorporate base mismatches. The PCR product was blunt-ended and cloned into SmaI cut and phosphatased pUC18. Six clones were identified which contained the PCR product. The clones were sequenced using the universal and reverse primers (Sequenase kit and Taqtrack kit). Clones with completely correct sequence through the transit peptide and the 5′ end of the ketothiolase gene up to a TthIII1 restriction site within the gene were identified. From one of these clones a TthIII-Kpn1 fragment was excised. The Kpn1 site was cut back to give a blunt end, and a TthIII1-Sma1 fragment of Alcaligenes eutrophus DNA from pKS-::2.3P7 corresponding to the major portion of the ketothiolase gone was inserted. Positive clones were sequenced across the joins. The transit peptide-ketothiolase fragment was excised and inserted into pJR1Ri.
For the transit peptide-reductase construct PCR was also utilised. This required only one PCR experiment as a Dde I site (unique in the transit peptide and reductase sequences) was present close to the 5′ end of the gene. The PCR experiment required two primers:
1. Sequence homologous to the 5′ end of the transit peptide which would allow extension toward the 3′ end. A Cla I site was incorporated into the sequence 5′ to the transit peptide sequence.
ACC ATC GAT GGA TGG CTT CTA TGA TAT CCT CTT CAG CT (SEQ ID NO: 6)
CLATP
2. Sequence homologous to just past the Dde I site in the reductase gene, linked in frame with 3′ transit peptide sequence to allow extension toward the 5 transit peptide.
ATG CGC TGA ATG CAC TTT ACT CTT CCA CCA TTG CTT GTA AT
TPDDER
After PCR with these two primers and transit peptide DNA as template the 195 bp product was identified on agarose gels and isolated by electroelution. DdeI XmnI reductese gene was isolated and ligated to DdeI cut PCR product. After agarose gel electrophoresis the 1.063 kb band was isolated, cut with ClaI and ligated into ClaI EcoRV Bluescript SK(-). Positives are being characterised.
3. Trans formation of plants with the PHB genes
3.1. Agrobacterium transformations Cesium-pure pJRIiT, pJRIiR, pJRIiS and pJRIi were individually transformed into Agrobacterium tumefaciens strain LBA4404 by direct uptake as is follows. LB (10 mls) was inoculated with A tumefaciens strain LBA4404. The culture was shake-incubated at 28° C. for approximately 16 hours until the optical density (OD) at 660 nm was 0.5. The cells were recovered by centrifugation (3000 rpm Sorvall RT6000B, 6 mins, 4° C.). They were resuspended in 250 μof ice-cold 20 mM CaC1 2 . The cell suspension was then dispensed into pre-chilled Eppendorf tubes in 0.1 ml aliquots. Approximately 1 μg of cassium-pure plasmid DNA was added to each tube. The cells were then heat-shocked by freezing in liquid nitrogen followed by incubation at 37° C. for 5 minutes. LB medium (1 ml) was added and the cells were allowed to recover by incubation (shaken) at 28° C. for 3-4 hours. The cell pellets were obtained by centrifugation (11,500 g, 30 seconds, 20° C.) and resuspended in 01. ml LB. Recombinant cells were selected on LB (agarsolidified) containing kanamycin (50 μg/ml), streptomycin (500 μg/ml) and rifampicin (100 μg/ml) following incubation at 28° C. Mini-prep DNA of the resultant Agrobacteriumu strains was then isolated and analysed by restriction enzyme digestion to ensure that no re-arrangements had occurred.
5 3.2. Plant Transformations
Tobacco leaf pieces and oilseed rape petioles were inoculated individually with strains LBA4404/JRIi LBA4404/pJRIiT, LBA4404/pJRIiR and LBA4404/pJRIiS. Plants were cultured in a growth room with a temperature of 25° C. and a photoperiod of 16 hours.
Brassica napus cv. Westar seedlings were sterilised in 10% sodium hypochlorite and washed in sterile water before germination on MS medium is (Imperial)(containing 3% sucrose and 0.7% phytagar (Gibco). The cotyledons were excised from 5 day old seedlings and the petioles of which were placed in MS medium as above but supplemented with 4.5 μg/ml benzylaminopurine (BAP). The cotyledons were cultured in this medium for 24 hours after which their petioles were dipped in an Agrobacterium solution. The Agrobacterium culture had been grown overnight in LB medium containing kanamycin (50 μg/ml) following which the Agrobacterium cells had been pelleted and washed in liquid MS medium and diluted to OD 660 0.1. The inoculated petioles were returned to the MS medium containing 4.5 μg/ml BAP and incubated in the culture room for 2 days. The cotyledons were then transferred to MS medium supplemented with BAP (4.5 μg/ml), carbenicillin (Duchefa) (500 μg/ml) and kanamycin (15 μg/ml). The cotyledons were subcultured on this medium every 2 weeks until the production of green callus and eventually shoots. Shoots were excised and cultured on MS containing carbenicillin (500 μg/ml) and kanamycin (15 μg/ml) until they were transferred to the glasshouse.
Nicotiana tabacum cv SRI seeds were sterilized as described above and germinated on MS medium (containing 3% sucrose and 0.8% bactoagar). The shoot tips from these seedlings were then micropropagated on this media to provide plants for transformation studies. Leaf pieces from these plants were dipped in an Agrobacterium solution (prepared as described above) and were then cultured on MS medium containing 3% sucrose, 0.8% bactoagar, 1 μg/ml BAP and 0.1 g/ml NAA, for 2 days. The leaf pieces were then cultured on the same media supplemented with carbenicillin (500 μg/ml) and kanamycin (100 μg/ml) for 5 weeks. Regenerated shoots were excised and cultured on MS containing 3% sucrose, 0.8% bactoagar, 200 μg/ml carbenicillin and 100 μg/ml kanamycin for 2 passages of 5 weeks before transfer to the glasshouse.
Kanamycin-resistant tobacco and rape plants were obtained for those transformed individually with JRIi, JRIiT, JRIiR and JRIiS.
3.3. Cotransforuations
Rape cotyledons and tobacco leaf pieces were also inoculated with mixtures of Agrobacterium strains. These inoculations were performed as described previously except that 1:1 mixtures of diluted Agrobacterium cultures, of the same optical density, were prepared immediately prior to inoculation.
4. Biochemical assessment of plants
Expression of Alcaligenes eutrophus PHA pathway enzymes in plant tissues was detected by enzyme activity assays. The presence of the enzyme polypeptides was also detected by Western blot analysis.
For the latter analyses rabbit polyclonal antibodies were raised to the purified β-ketothiolase and NADP acetoacetyl CoA reductase enzymes from Alcaligenes eutrophus . Bacteria were pelleted, washed, and crude extracts prepared as described by Haywood and Large (1981, Biochem J, 199, 187-201). β-ketothiolase A was purified by chromatography on hydroxylapatite followed by anion exchange chromatography on FPLC mono Q, followed by gel filtration on Superdex S-200 (Pharmacia), using modifications of methods described by AHaywood et al (1988, FEMS Microbiology Letters, 52, 91-96). NADP acetoacetyl-CoA reductase was purified using the same techniques, with an additional affinity chromatography step on 2′, 5′ ADP sepharose (Pharmacia). Purified proteins were subjected to sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) according to the method of Laemmli (1970, Nature, 222, 680-685). The final β-ketothiolase preparation showed a single coomassie blue stained band at 41 kd. The final reductase preparation showed a major band at 26 kd. 3 mg of purified ketothiolase and 2 mg of purified reductase were subjected to preparative SDS PAGE. The bands corresponding to the two enzymes were electroeluted from the gels and injected into rabbits to raise polyclonal antibodies. Sera from primary and secondary bleeds following injection were shown to contain antibodies specific for their target enzymes via Western blot analyses of crude Alcalienes extracts.
Crude extracts of tobacco leaves were prepared by grinding leaf tissue in 50 mM potassium phosphate buffer pH7.0 containing 1 mM dithiothreitol. After centrifugation at 30,000 g, enzyme assays for ketothiolase and acetoacetyl CoA reductase were conducted on aliquots of the supernatants by the methods described by Raywood et al (1988, TEMS Microbiology Letters, 52, 91-96; 52, 259-264). PHB synthase assays were conducted on aliquots of the 30,000 g supernatants and aliquots of the pellets, resuspended in extraction buffer, by the method of Haywood et al (1989, FREMS Microbiology Letters, 57, 1-6).
For Western blot analysis, aliquots of the 30,000 g supernatants were subjected to SDS PAGE and electrophoretically transferred to nitrocellulose filters. Filters were then rinsed in TBS (50 mm Tris-RCl pH7.9, 150 mM NaCl) and incubated in TBS plus 5% bovine serum albumin. Proteins reacting with anti-ketothiolase or anti-reductase serum were detected by incubating the filters in 100 ml TBS containing 2 ml of the relevant serum for 1-2 h. Bound first antibody was subsequently detected using goat anti-rabbit IgG alkaline phosphatase conjugate and nitroblue tetrazolium alkaline phosphatase colour development reagent (BioRad Laboratories).
Initial biochemical analyses were carried out on subcultured tobacco plants growing in tissue culture. Eighteen kanamycin resistant plants transformed with JR1i ketothiolase were subjected to enzyme analysis and results compared with untransformed control plants. Leaves of the same size were extracted.
FIG. 4 shows the β-ketothiolase enzyme activities in the tobacco leaves, The identification numbers of individual plants are shown on the x axis. Plants to the left of the dotted line are untransformad control plants. Plants to the right of the line are transformed with JR1i ketothiolase.
A low level of ketothiolase activity was detected in untransformed control plants. Nearly all of the JR1i ketothiolase transformed plants had ketothiolase activity higher than control. The highest activity was 34 nmol/min/mg protein, 2.8 times higher than the highest control plant. In is Western blots the anti-ketothiolase antibody detected a polypeptide at 41 kd in untransformed control tobacco plants—possibly corresponding to the endogenous ketothiolase enzyme activity. While a 41 kd polypeptide was also detected in extracts of JR1i ketothiolase transformed plants, the Western blots could not quantitatively distinguish transformed from untransformed plants.
FIG. 6 shows the NADP acetoacetyl CoA reductase enzyme activities in leaves of the tissue culture grown tobacco plants. The identification numbers of individual plants are shown on the x axis. Plants to the left of the dotted line are untransformed control plants. Plants to the right of the line are transformed with pJR1i reductase.
A low level of acetoacetyl CoA reductase activity was detected in untransformed control plants. Nearly all the 21 Jr1i reductase transformed plants had reductase activity higher than control. The highest activity was 30 nmaol/min/mg protein, 4 fold higher than the highest control plant. In Western blots the anti-roductase antibody did not detect any polypeptide with a m.w. of 26 kd in extracts of untransformed control plants. A 26 kd Polypeptide was however detected in extracts of the JR1i reductase transformed plants. Expression of the bacterial reductase gene in tobacco leaves was therefore demonstrated.
6
29 base pairs
nucleic acid
single
linear
DNA (genomic)
unknown
1
AAATGGCTTC TATGATATCC TCTTCAGCT 29
47 base pairs
nucleic acid
single
linear
DNA (genomic)
unknown
2
ACGATGACAA CGTCAGTCAT GCACTTTACT CTTCCACCAT TGCTTGT 47
50 base pairs
nucleic acid
single
linear
DNA (genomic)
unknown
3
ATTACAAGCA ATGGTGGAAG AGTAAAGTGC ATGACTGACG TTGTCATCGT 50
25 base pairs
nucleic acid
single
linear
DNA (genomic)
unknown
4
ACCCCTTCCT TATTTGCGCT CGACT 25
38 base pairs
nucleic acid
single
linear
DNA (genomic)
unknown
5
ACCATCGATG GATGGCTTCT ATGATATCCT CTTCAGCT 38
44 base pairs
nucleic acid
single
linear
DNA (genomic)
unknown
6
ATGCGCTGAG TCATGCACTT TACTCTTCCA CCATTGCTTG TAAT 44 | A plant which produces polyhydroxy-alkanoate polymer has a recombinant genome which contains one or more than one of the genes specifying enzymes critical to the polyhydroxyalkanoate biosynthetic pathway which occurs in certain micro-organistas such as Alcaligenes eutrophus which naturally produce same. The plant species is preferably an oil-producing plant. | 2 |
FIELD OF INVENTION
This invention relates generally to a binder and, more particularly, to a versatile binder having a partition for defining a ring binder space and a storage space.
BACKGROUND OF THE INVENTION
Loose-leaf documents and other sheet-like elements are often bound in a supporting binder. The loose-leaf documents are easily removed, and the binder is readily reused if the contents are no longer needed. Most commonly, three ring binders are used. These binders have a spine or base hingedly connected to a front and back cover. The spine or base may be a solid backing member to which a ring assembly is secured. Alternatively, the ring assembly may be secured to one of the covers immediately adjacent to a spine. The front and back covers may be formed of a relatively flexible material, or a relatively stiff material interconnected to the spine or base through a suitable flexible connection therebetween.
Other than having interior and exterior pockets for carrying loose sheets of paper, these types of binders are not designed to carry items often carried in a briefcase or backpack such as a book, notebook, calculator, cellular phone, notebook computer, palm top computer, key chain, and office supply items such as a pen, tape, marker, ruler, and etc. To accommodate these items, students usually carry their books and other school related items to/away from campus in a backpack. While on campus, the student has no need for the backpack because most of the items are left in a campus locker during the school day. Usually, only a binder and several additional items are needed for a particular class, and accordingly the student must either take the bulky backpack to class, or cram the needed extra items into his/her pockets or in the three ring binder. In another example, professionals generally carry a briefcase to/away from the office but would prefer to attend meetings with only a binder and a few additional items such as a cellular phone, small calculator, and a few key papers.
BRIEF SUMMARY OF THE INVENTION
Thus, there remains a long felt need for a relatively compact binder assembly capable of carrying loose-leaf documents and other items commonly carried in a briefcase or backpack. There also remains a need to provide a binder assembly which is aesthetically pleasing and yet rugged and mass producible at a reasonable price.
In accordance with the present invention, a partitioned binder assembly is provided which is substantially smaller than a briefcase or backpack but is capable of storing a three ring binder and other items commonly carried in a briefcase or backpack. The partitioned binder assembly includes a partition separating a ring binder compartment from a storage compartment. The binder assembly includes a spine, a rear cover, and a front cover (partition). The rear and front cover are pivotally mounted to the spine and define a ring binder space for holding pages. The ring binder space is closed on one side where the rear and front cover are secured to the spine and selectively open on the other three sides. A ring binder is mounted in the ring binder space near the spine.
A storage cover is pivotally mounted to the front cover. The storage cover and the front cover define a storage space for holding a book, notebook, calculator and other items. The storage space is closed on one side where the storage cover is secured to the front cover and is selectively open on the other three sides. First and second zippers extend around the three open sides of the binder and storage space, respectively, to fully enclose the contents of the binder assembly.
In accordance with a preferred embodiment of the invention, the binder assembly may include some or all of the following features: 1) the ring binder compartment and storage compartment may be open at the same three sides, with parallel zippers extending around the three sides; 2) the storage compartment may include a file folder, a floppy disk storage arrangement, a calculator storage arrangement, writing utensil loops, and additional pocket(s); and 3) a removable ring binder member may be sized to fit into an inner pocket of the ring binder compartment.
Other objects, features, and advantages of the present invention will become apparent from a consideration of the following detailed description and from the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a perspective view of an exemplary binder of the present invention in a closed configuration;
FIG. 2 is a top view of the exemplary binder shown in FIG. 1;
FIG. 3 is a rear view illustrating a spine of the exemplary binder shown in FIG. 1;
FIG. 4 is a side view illustrating the front of the exemplary binder with two parallel zippers, as shown in FIG. 1;
FIG. 5 is a side view illustrating the top of the exemplary binder shown in FIG. 1;
FIG. 6 is a side view illustrating the bottom of the exemplary binder shown in FIG. 1;
FIG. 7 is a plan view of the exemplary binder shown in FIG. 1 in an open configuration illustrating a ring binder compartment; and
FIG. 8 is a perspective view of the exemplary binder shown in FIG. 1 in an open configuration illustrating a storage compartment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention relates to a binder assembly having a ring binder compartment and a storage compartment separated by an intermediate panel. The ring binder compartment is suited to store any type of loose-leaf material. The storage compartment is suited for storing items generally carried in a briefcase or backpack such a book, notebook, calculator, and cellular phone. In the particular embodiment shown in the drawings and herein described, the binder is a three ring binder for the releasable binding of reports, records, and like assemblies of papers, films and the like. However, it should be understood that the principles of the invention are equally applicable to virtually any form of binder. Therefore, it is not intended to limit the principles of the present invention to the specific embodiments shown and such principles should be broadly construed.
Referring to FIGS. 1-6, a binder assembly 10 of a standard size for sheets is illustrated. Typical sheet size is A-4 size paper or paper having dimensions of 81/2 inches by 11 inches. The binder assembly 10 includes a spine 12, a rear cover 14, an intermediate panel 16 and a front cover 18. The rear cover 14 is pivotally mounted to a rear edge 20 of the spine 12 by a first hinge 22, and the intermediate panel 16 and front cover 18 are pivotally mounted to a front edge 24 of the spine 12 by a second 26 and third hinge 28, respectively. Each of the covers 14, 18 and panel 16 has a width of about 11 inches and a length of about 121/2 inches, and the spine 12 may have a width of about 21/2 inches. The binder assembly 10 includes a three ring binder member 30 having rings 32 adapted to be opened for receiving 81/2 inches by 11 inches sheet-like material having spaced holes along the inner edge for alignment with the rings 32.
Many other types of binders exist such as binders having more or less than three rings. The rings may be formed of a metal such as steel or a lightweight and inexpensive material such as a plastic. The binder assembly may also be sized to accommodate sheets larger or smaller than 81/2 inches by 11 inches. For example, a typical carry-type organizer and calendar are usually about 5 inches by 7 inches. The present invention is intended to work equally well with these and other types of binders.
In the particular embodiment shown in the drawings and herein described, the spine 12, rear cover 14, intermediate panel 16, and front cover 18 are each formed of a relatively stiff and continuous construction. The covers 14, 18 and panel 16 each include an inner base plate (not shown) of paperboard or other suitable material. The base plates provide structural support and are relatively flexible. Each base plate extends substantially throughout the complete width and length of each of the covers 14, 18 and panel 16. A decorative and utilitarian enclosure or shell 34 is fabricated enclosing the base plates. Preferably, the shell 34 is formed from a woven fabric material which is treated with an UV resistant and water repellent coating. The fabric material may be formed from nylon, polyester, or polyvinyl chloride. An outer surface 36 of the spine 12 may further include a reflective strip 38 for safety purposes, wherein the strip 38 reflects light from a vehicle. In addition, a thin foam layer (not shown) may be provided between the inner base plates and the shell 34 to give the binder assembly 10 a softer feel and to protect the contents of the binder assembly 10.
Referring to FIG. 7, the binder assembly 10 is in an open configuration to illustrate a ring binder compartment 40. In a closed configuration, the ring binder compartment 40 occupies the space between the rear cover 14 and intermediate panel 16 and extends outwardly to the outer edges of the rear cover 14 and intermediate panel 16. In an open configuration, the intermediate panel 16, spine 12, and rear cover 14 define the outer edges of the ring binder compartment 40, i.e., a front edge 42, rear edge 44, top edge 46, and bottom edge 48. The ring binder compartment 40 is selectively opened and closed by a zipper 50 connecting a first flexible sidewall 52 to a second flexible sidewall 54, wherein the zipper 50 includes a first 56 and second row 58 of interlocking tabs. One edge of the first sidewall 52 is attached to the rear cover 14, and the opposite edge of the first sidewall 52 is attached to the first row 56 of interlocking tabs. One edge of the second sidewall 54 is attached to the intermediate panel 16, and the opposite edge of the second sidewall 54 is attached to the second row 58 of interlocking tabs. The depth of the ring binder compartment 40 is about 21/2 inches, which is the combined width of the first sidewall 52, zipper 50, and second sidewall 54.
With further reference to FIG. 7, the ring binder compartment 40 further includes a ring binder pocket 60 which extends from the bottom edge 48 to the top edge 46 of the rear cover 14 and from the rear edge 44 to a region near the spine 12 such that the dimensions of the ring binder pocket 60 are substantially the same as the outer dimensions of the rear cover 14. The ring binder pocket 60 comprises a pocket layer 62 with a top 64, bottom 66 and rear side 68 respectively attached to the top 46, bottom 48, and rear edge 44 of an inner surface of the rear cover 14. The side near the spine 12 is left unsecured to define a side insert opening 70. The three ring binder may be inserted into the pocket 60 through the side insert opening.
The rings 32 of the three ring binder member 30 are coupled to a base member 72 having dimensions similar to the dimensions of the ring binder pocket 40. The base member 72 may be coupled to the pocket 60 by slidingly inserting the base member 72 into the pocket 60, and the three ring binder member 30 may be decoupled from the pocket 60 by slidingly pulling the base member 72 out of the pocket 60. One of the advantages of such a configuration is that a user may easily replace one ring binder member with a set of papers to another ring binder member with another set of papers.
The ring binder compartment 40 further includes a plurality of pockets 74, 76, 78 on a surface of the intermediate panel 16. Each of the plurality of pockets comprises a pocket layer with three sides secured to the surface of the intermediate panel and a fourth side left unsecured to define an insert opening. In one of the pockets 78, the unsecured side includes a zipper 80 such that the pocket 78 may be selectively opened and closed.
Referring to FIG. 8, the binder assembly 10 is in an open configuration to illustrate a storage compartment 82. In a closed configuration, the storage compartment 82 occupies the space between the intermediate panel 16 and front cover 18 and extends outwardly to the outer edges of the intermediate panel 16 and front cover 18. In an open configuration, the front cover 18 and intermediate panel 16 define the outer edges of the storage compartment 82, i.e., a front edge 84, rear edge 86, top edge 88, and bottom edge 90. The storage compartment 82 is selectively opened and closed by a zipper 92 connecting a third sidewall 94 to a fourth sidewall 96, wherein the zipper 92 includes a third 98 and fourth row 100 of interlocking tabs. One edge of the third sidewall 94 is attached to the intermediate panel 16, and the opposite edge of the third sidewall 94 is attached to the third row 98 of interlocking tabs. One edge of the fourth sidewall 96 is attached to the front cover 18, and the opposite edge of the fourth sidewall 96 is attached to the fourth row of interlocking tabs 100. The depth of the storage compartment 82 is about 2 inches, which is the combined width of the third sidewall 94, zipper 92, and fourth sidewall 96. As discussed previously, the storage compartment 82 may be used to store a book, a notebook or palm top computer, a day planner, or any other relatively large item. That is, items which would normally be carried in a briefcase or backpack may be carried in the storage compartment 82.
With further reference to FIG. 8, the storage compartment 82 includes a pocket 102 which extends from the bottom edge 90 to the top 88 edge of the intermediate panel 16 and from the rear edge 86 to a region near the third hinge 28 such that the dimensions of the pocket 102 are substantially the same as the outer dimensions of the intermediate panel 16. The pocket 102 comprises a pocket layer 104 with a top 106, bottom 108, and rear side 110 respectively attached to the top 88, bottom 90, and rear edge 86 of the intermediate panel 16. The side near the third hinge 28 is left unsecured to define a side insert opening 112. Sheets of paper as large as 81/2 inches by 11 inches may be inserted into the pocket 102 through the side insert opening 112.
The storage compartment 82 includes a file folder 114 attached to an inner surface of the front cover 18 and has dimensions slightly smaller than the outer dimensions of the front cover 18. The file folder 114 includes a file folder panel 116 pivotally mounted by a fourth hinge 118 which is adjacent to the third hinge 28. A top 120 and bottom side 12 of the file folder panel 116 are attached to the inner surface of the front cover 18 by flexible side extensions 124, and the side opposite the fourth hinge 118 is left unsecured to define an insert opening 126. The file folder 114 may be use to carry loose sheets of paper, spiral-bound notebook, book, or other items.
With further reference to FIG. 8, a plurality of separate storage arrangements is mounted to the file folder panel 116 such as a floppy disk storage arrangement 128, a calculator storage arrangement 130, and a writing utensil storage arrangement 132. The floppy disk storage arrangement 128 includes a meshed cover 134 closed on three sides and open on the remaining side. The three sides, which are closed, are attached to the file folder panel, and a zipper 136 is coupled to the other side to allow the arrangement to be selectively opened or closed. The calculator storage arrangement 130 includes a wall 131 having four sides. One side is pivotally mounted to the file folder panel by a hinge, while the side opposite the hinge is selectively opened and closed by a flap 138 which may be secured/unsecured to the wall by VELCRO® hook and loop material (not shown). The remaining two sides are attached to the file folder panel 116 with flexible extensions 140 which have a width of about 2 inches. It is noted that the flap 138 may be secured by other means such as a zipper, clip, or any other means known to one skilled in the art. The calculator storage arrangement 130 may be used to carry items other than a calculator such as a cellular phone, tape recorder, etc. The writing utensil storage arrangement 132 includes a plurality of loops 142 for holding writing utensils such as pencils, pens, and markers.
Although the present invention has been described in detail with regarding the exemplary embodiment and drawing thereof, it should be apparent to those skilled in the art that various adaptations may be accomplished without departing from the spirit and scope of the invention. For instance, the binder assembly may further include a second or more storage compartments. Further, the storage compartment may be selectively opened and closed by other means such as a strap and clip arrangement. It is also noted that the three open sides of the ring binder compartment and/or the storage compartment may be held closed by strips of hook and loop material in whole or in part or by any other suitable closures instead of by zippers. Still further, the storage compartment may have outer dimension substantially smaller than the outer dimensions of the ring binder compartment, wherein a hinge for the front cover is located on the central portion of the intermediate panel. The hinge for the storage compartment may be located on a side opposite the hinge for the ring binder compartment. Accordingly, the invention is not limited to the precise embodiment shown in the drawings and described in detail hereinabove. | A binder assembly having a partition separating a ring binder compartment from a storage compartment. The binder assembly includes a spine, a rear cover, and a front cover. The rear cover and front cover are pivotally mounted to the spine. The rear and front cover define a ring binder space for holding pages, closed on one side where the rear and front cover are secured to the spine, and being selectively open on the other three sides. A ring binder is mounted in the ring binder space near the spine. A storage cover is pivotally mounted to the front cover. The storage cover and the front cover define a storage space closed on one side where the storage cover is secured to the front cover, and being selectively open on the other three sides. First and second zippers extend around the three open sides of the binder and storage space, respectively, to fully enclose contents of the binder assembly. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to biodegradable non-ionic surfactants.
2. Description of the Prior Art
A wide variety of non-ionic surface-active agents are known in the art. Because of their non-ionic nature, these surface-active agents are usually stable in acid, basic and neutral media. Recently, biodegradable polyoxyalkylene copolymer surfactants have been disclosed in U.S. Pat. Nos. 3,931,337 and 4,189,609. These are prepared from individual blocks of polymers and copolymers of alkylene oxides by reaction with formaldehyde or a dialkyl carbonate. The surfactant molecules fragment into individual polyoxyalkylene glycols under the influence of biologic agents or by hydrolysis or when exposed to slightly acidic or basic conditions. Surface-active acetals and formals are disclosed in U.S. Pat. No. 2,905,719. These are ethylene oxide derivatives coupled to the residue of an alkyl alcohol having 8 to 18 carbon atoms utilizing formaldehyde or acetaldehyde. Acid-sensitive non-ionic surface-active compositions are thereby produced which are stable in basic or neutral media. Surface-activity is lost upon treating these non-ionic acetals with an acid.
In U.S. Pat. No. 2,796,401, complex formal lubricating compositions are disclosed which are the reaction product of monohydric aliphatic or aromatic alcohol, or a glycol with formaldehyde as a coupling agent. The product is made in two stages in which, in the first stage, the hemiformal of the alcohol is made by heating equal moles of the alcohol and formaldehyde. Subsequently, in the second stage, the desired molar proportion of glycol and formaldehyde is added to the hemiformal and reacted to make the desired product.
In U.S. Pat. No. 2,786,081, acetal condensation products are disclosed which are the reaction products of diethylene glycol and formaldehyde. These are useful as plasticizers for polymers including film-forming materials.
SUMMARY OF THE INVENTION
Biodegradable and acid degradable non-ionic surface-active compositions are disclosed containing the residue of a secondary carboxamide, hereafter referred to as a monofunctional amide or a sulfonamide compound coupled to a hydrophilic polyoxyalkylene glycol derived from at least one alkylene oxide having 2 to 4 carbon atoms. The compositions contain at least one terminal hydrophobic group derived from the monofunctional amides or sulfonamides. The aldehyde coupling agent can be any aliphatic aldehyde having up to 4 aliphatic carbon atoms such as formaldehyde, acetaldehyde, propionaldehyde, and butyraldehyde. Preferably the aldehyde is formaldehyde or acetaldehyde and most preferably the aldehyde is formaldehyde.
The acid sensitive nature of the compositions of the invention permits the biodegradation into relatively environmentally inoccuous fragments upon exposure of the surface-active agents of the invention to water and atmospheric oxygen. The surface-active agents of the invention can also be split into relatively non-surface-active fragments upon reducing the pH of the media below 7. Therefore, the surface-active agents of the invention are particularly useful where it is desired to form an emulsion and then coagulate the emulsion simply by lowing the pH below 7. Unexpectedly, the surface-active agents of the invention have unusually low viscosity. The surface-active agents of the invention are unexpectedly formed by a sequential coupling mechanism in which a monofunctional hydrophobic amide or sulfonamide is coupled with a hydrophilic polyoxyalkylene glycol, as indicated by the water-soluble product obtained. Sequential coupling rather than the expected random coupling of each of the reactants occurs since water-insoluble species are not formed.
DETAILED DESCRIPTION OF THE INVENTION
The surface-active agents of the invention have the formulas: ##STR1## wherein R 1 is the residue of a hydrophobic monofunctional organic compound selected from the group consisting of at least one of an alkyl, alkylaryl, arylalkyl, and alkylarylalkyl group; wherein each alkyl group has about 6 to about 30 carbon atoms; B is C═O, O═S═O or mixtures thereof; and wherein R 2 is hydrogen or alkyl of 1 to about 4 carbon atoms; R 3 is alkyl or hydroxyl substituted alkyl of 1 to about 4 carbon atoms; A is the residue of a hydrophilic oxyalkylene polymer derived from the same or different alkylene oxides wherein said polymer is selected from at least one of the group consisting of polyalkylene glycols derived respectively from the reaction of ethylene oxide or ethylene oxide and alkylene oxides having 3 to 4 carbon atoms with an active hydrogen compound having at least 2 active hydrogen atoms; x is an integer of 1 to 20, preferably 1 to 10, and n is individually selected from integers such that the molecular weight is about 104 to about 1000.
The hydrophilic polyoxyalkylenes utilized in the preparation of the surface-active agents of the invention are prepared in a conventional manner by reacting an alkylene oxide or mixture thereof with an initiator compound containing at least one active hydrogen atom. Preferably, the initiator compounds have molecular weights of less than 100. Like most surface-active agents, the surface-active agents of the invention are composed of hydrophilic and hydrophobic portions in the same molecule. As is well known in this art, ethylene oxide or mixtures thereof with other lower alkylene oxides can be employed to provide the hydrophilic portion of the molecule. The surface-active compounds of the invention preferably contain the residue of a monofunctional, aliphatic amide or sulfonamide; such as an alkyl amide or an alkyl sulfonamide having about 6 to about 30 carbon atoms in the alkyl group to provide the hydrophobic portion of the molecule.
The alkylene oxides which can be employed as reactants in the formation of the hydrophilic polyoxyalkylenes are the lower alkylene oxides having 2 to 4 carbon atoms. Examples of such alkylene oxides are ethylene oxide, propylene oxide, the various butylene oxides, and tetrahydrofuran. Mixtures of ethylene oxide with other lower alkylene oxides can be employed to obtain varying degrees of hydrophilicity. The hydrophilic polyoxyalkylene polymers utilized as reactants can have a molecular weight of about 104 to about 1000. Preferably, the molecular weight is about 200 to about 1000. The preferred use of relatively low molecular weight alkylene oxide polymers provides economies in the preparation of surface-active agents in that the reaction time to produce conventional surface-active agents based upon polyoxyalkylenes can be considerably reduced. The use of relatively low molecular weight polyoxyalkylene polymers, coupled in accordance with the process of the invention, also provides readily biodegradable surfactants. Upon degradation, not only do these split off low molecular weight polyoxyalkylene polymers exhibit relatively little surface-active effects but these polymers are, in turn, more readily oxidized than similar high molecular wight species when exposed to water and atmospheric oxygen. Thus, the surface-active agents of the invention can provide all the advantageous surface-active properties of high molecular weight polyoxyalkylene polymer prior art non-ionic surfactants. When such surfactants are fragmented such as by reducing the pH of the media in which the surfactant is present to below 7, the individual polyoxyalkylene polymer fragments readily oxidize and can be biodegraded.
The low molecular weight hydrophilic polyoxyalkylene copolymers employed in this invention are generally prepared by carrying out the condensation reaction of the alkylene oxides with an active hydrogen-containing initiator in the presence of an alkaline catalyst in a manner well known to those skilled in the art. Any of the types of catalysts commonly used for alkylene oxide condensation reactions may be employed. Catalysts which may be employed include sodium hydroxide, potassium hydroxide, sodium methylate, sodium ethylate, potassium acetate, sodium acetate, tributylamine and triethylamine. After the condensation reaction is completed, the catalyst may be removed from the reaction mixture by any known procedure such as neutralization, filtration or ion exchange. The condensation is preferably carried out at elevated temperatures and pressures.
The term "active hydrogen atom" is well known to those skilled in the art. It is sufficiently labile to react with ethylene, propylene or butylene oxide and it reacts with methyl magnesium iodide, liberating methane according to the classical Zerewitinoff reaction. The hydrogen atoms are members of a functional group such as a hydroxyl group, a phenol group, a carboxylic acid group, or an amide group. Hydrogen atoms may be activated by proximity to carbonyl groups such as acetoacetic ester. Examples of active hydrogen initiator compounds, which can be used include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, amylene glycol, hexylene glycol, heptylene glycol and octylene glycol.
Together with the use as reactants of hydrophilic polyoxyalkylene polymers, the surface-active compositions of the invention employ monofunctional amides, monofunctional sulfonamides, or mixtures thereof as reactants so as to provide at least one terminal hydrophobic group on each molecule of the surface-active compounds of the invention. These can be aliphatic or aliphatic-aromatic such as alkyl, alkylaryl, arylalkyl, and alkylarylalkyl amides and sulfonamides. The preferred monofunctional amides and sulfonamides have aliphatic groups containing about 6 to about 30 carbon atoms, most preferably about 8 to about 20 aliphatic carbon atoms. The aliphatic groups can be substituted or unsubstituted.
Examples of useful secondary alkyl amides are n-ethyloleylolamide, N-(2-hydroxy)ethyl-lauramide, N-methylpalmitamide, N-butyl-stearamide, etc.
Useful secondary amides include arylalkyl amides having about 6 to about 30 carbon atoms in the alkyl chain such as 8-phenyl-N-ethyl-caprylamide. Useful alkylaryl amides include dodecyl-N(2-hydroxyethyl)benzamide. Useful alkyl amides include N-dodecyl-N-butyl-acetamide. Useful monofunctional alkyl sulfonamides include N-dodecyl-N-butyl-sulfonamide. Useful alkylaryl sulfonamides include 4-dodecyl-phenyl-N-methyl-sulfonamide. Useful arylalkyl sulfonamides include 4-octyl-N-propyl-benzene sulfonamide. Useful alkylarylalkyl sulfonamides include 2-(4-dodecylphenyl)-N-methyl-sulfonamide.
Any of the monofunctional amides and sulfonamides set forth above can have substituents which do not contain active hydrogen such as halogen, for example, chlorine, bromine, and iodine, nitrate groups, or alkoxy radicals.
The aldehydes utilized to couple the hydrophilic polyoxyalkylene glycols and hydrophobic monofunctional amides or sulfonamides are aliphatic aldehydes generally having 1 to about 4 carbon atoms in the alkyl group. Preferably, the aldehydes contain an alkyl chain which most preferably has 1 to about 2 carbon atoms. Examples of useful aldehydes are formaldehyde, acetaldehyde, propionaldehyde, and butyraldehyde.
In the preparation of the surface-active compounds of the invention, at least one each of the hydrophilic and hydrophobic compound reactants are admitted to a reaction zone and coupled with an aldehyde in a single stage reaction at reflux temperature in the presence of an acid catalyst and a reaction solvent. Generally, the reaction is carried out at a temperature of about 25° C. to 150° C. Examples of useful acid catalysts for the coupling reaction are sulfuric acid, hydrochloric acid, hydrobromic acid, para-toluene sulfonic acid, phosphoric acid, trifluoroacetic acid, methane sulfonic acid, and trichloroacetic acid. Preferably sulfuric acid is utilized as the catalyst. The amount of acid catalyst employed can vary from about 0.01 percent by weight to about 3 percent by weight based upon the total weight of the reactants present. Usually, the reaction is carried out in the presence of an organic reaction solvent which is immiscible with water. The solvent is employed so as to allow removal of the water of reaction by azeotropic distillation. Examples of useful solvents are benzene, toluene, xylene, hexane, and cyclohexane. The time required for the completion of the coupling reaction is generally from about 15 minutes to 10 hours. Preferably, the reaction is completed within 5 hours.
The following examples will further illustrate the method of preparation of the non-ionic, surface-active agents containing acetal groups and their use as surface-active agents. These examples, however, are not to be considered as limiting the scope of the invention. In the specification, claims and examples which follow, all parts, percentages, and proportions are by weight and all temperatures are in degrees centigrade unless otherwise noted.
EXAMPLE 1
Into a one-liter capacity flask equipped with a thermometer, stirrer, and Dean Stark type moisture trap and condenser, there were added 128 grams of the monoethanolamide of cocoanut oil fatty acids, 300 grams of a polyethylene glycol having a molecular weight of 300, 34 grams of paraformaldehyde and 1.5 grams of concentrated sulfuric acid together with 100 milliliters of cyclohexane. After starting agitation, the mixture was heated to reflux temperature and water was removed azeotropically over a period of about 145 minutes. The residual cyclohexane was then removed by distillation. Five grams of sodium bicarbonate were added to neutralize the catalyst and 3 grams of an oxyalkylene polyol sold under the trademark QUADROL® were added as a stabilizer. The amount of product obtained was 434 grams. The appearance of the product was a clear yellow liquid. The product was further characterized as having a pH (1 percent by weight aqueous solution) of 8.0, a cloud point (1 percent by weight aqueous solution) of greater than 75° C., a surface tension of 26 dynes per centimeter at 0.1 percent by weight concentration in water, and a Draves sink time of 68 seconds at 0.1 percent by weight concentration in water.
EXAMPLE 2
Example 1 is repeated substituting a polyoxyalkylene block copolymer derived from the reaction of ethylene oxide and propylene oxide for the polyethylene glycol of Example 1.
EXAMPLE 3
Example 1 is repeated substituting a heteric polyoxyalkylene glycol for the polyethylene glycol of Example 1.
EXAMPLE 4
Example 1 is repeated sustituting a mixture of the polyethylene glycol of Example 1 and an oxyalkylene block copolymer derived from the reaction of ethylene oxide and propylene oxide for the polyethylene glycol of Example 1.
EXAMPLE 5
Example 1 is repeated sustituting a mixture of the polyethylene glycol of Example 1 and a heteric copolymer derived from the reaction of ethylene oxide and propylene oxide for the polyethylene glycol of Example 1.
EXAMPLE 6
Example 1 is repeated sustituting a heteric-block copolymer of polyethylene glycol and an oxyalkylene block copolymer derived from the reaction of ethylene oxide and propylene oxide for the polyethylene glycol of Example 1.
EXAMPLE 7
Example 1 is repeated substituting 143 grams of N-methyl stearamide for the monoethanolamide of the cocoanut fatty acids used in Example 1.
EXAMPLE 8
Example 1 is repeated substituting 86 grams of the N-2-hydroxypropylamide of oleic acid for the amide of Example 1.
While this invention has been described with reference to certain specific embodiments, it will be recognized by those skilled in the art that many variations are possible without departing from the scope and spirit of the invention. | Acetal-coupled non-ionic surfactants are easily degraded into relatively environmentally inoccuous fragments having little or no surface activity. The fragments are sufficiently low in molecular weight to be oxidized when exposed to water and atmospheric oxygen. Surface activity can also be destroyed by lowering the alkalinity of the medium in which the non-ionic surfactant is utilized to below pH 7. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates generally to resilient pads which are placed under sports floor systems such as gymnasiums, exercise floors, and the like. More particularly, the invention relates to such a pad which is designed to provide desirable response and shock absorption characteristics under a wide variety of floor loads.
It is generally known to provide cushioning pads under a sports flooring system in order to provide resiliency to the floor. In such known systems, the amount of cushioning provided by the pads is generally controlled by the durometer, i.e., the hardness, of the pads. There are both advantages and disadvantages to using either hard or soft pads.
Specifically, in sports such as basketball and racquetball, it is important that the floor be relatively stiff, so that the ball bounces back easily and uniformly throughout the floor. High durometer (hard) resilient pads produce a floor having preferred ball response characteristics. However, such hard pads do not deform easily when the floor is placed over an uneven base substrate. If there is a loss of contact between a particular pad and the base substrate, a "dead spot" will be created, causing very poor ball response at that point. Furthermore, hard pads provide little shock absorption, and have a greater potential to cause harm to the athlete. This problem is especially severe when heavy loading occurs from a number of athletes performing in close proximity to each other.
Low durometer (soft) resilient pads provide greater shock absorption and hence provide a higher level of safety to the athlete. These resilient pads also provide for high deflection under light loads, and hence can conform to uneven base substrates, reducing the problem of "dead spots." However, floors employing such soft pads do not produce desirable ball response characteristics under normal loading conditions, and thus are not highly suitable for sports such as basketball and racquetball. Furthermore, soft pads are prone to "compression set" which is a permanent change in profile after the pad has been subjected to high loads for a long period of time. Such compression set can occur in areas where bleachers, basketball standards, or other gymnasium equipment are likely to be placed for periods of time.
Numerous attempts have been made to design a resilient pad which will produce a flooring system having the desirable characteristics of both hard and soft resilient pads, without the disadvantages of each. One such example is U.S. Pat. No. 4,890,434 to Niese. Niese discloses a pad having a frusto-conical shape with an interior relieved area which increases deflectability.
The resilient pad of Niese, however, has several disadvantages. First, the pad provides only a limited change in the response characteristics as compared to a standard pad. Second, the resiliency of the pad cannot easily be changed, for example, in order to customize the pad to a particular floor system. Third, the pad is relatively expensive to produce, as the pad is complex in shape and must be produced in a mold.
SUMMARY OF THE INVENTION
The present invention includes a resilient pad for placement under a floor system. The pad is made up of a plurality of pad elements spaced longitudinally apart. At least one of the pad elements has a thickness which is greater than another of the pad elements.
Preferably, the pad elements are cylindrical in shape, and are aligned with their longitudinal axes extending generally parallel to each other and to the plane of the floor. The thickness of the pad elements is varied by varying the diameter of the cylinders. The resilient pad also preferably includes a base layer to which the pad elements are attached. In such a case, the resilient pad can be attached to the flooring system via the base layer, for example by stapling.
In the most preferred arrangement, the resilient pad has a first pad element having the greatest diameter centrally disposed on the base layer, two second pad elements of lesser diameter, one located on either side of the first pad element, and two third pad elements of lesser diameter still, one being located on either side of the second pad elements.
The resilient pad of the present invention provides desirable response and shock-absorption characteristics over a wide range of applied loads. The larger-diameter pad element deforms relatively easily under light loads, so that the floor conforms to uneven substrates, preventing dead spots. As the loading is increased, the adjacent pad elements of lesser thickness respond. Hence, if a large load is applied to a small area, such as by a number of athletes concentrated in one place, the other pad elements of lesser thickness provide increased resistance to deformation. Also, with the pad of the present invention, there is no need for an increased number of pads under heavy load areas such as bleachers, basketball goals, etc.
The resilient pads of the present invention are also cheaper and easier to manufacture than previous pads. The pads are preferably made out of natural rubber, PVC, neoprene, polyurethane, nylon, or other resilient material. The material for the resilient pads can be formed in long lengths by extrusion. The resilient pads can then simply be cut to the desired length.
Through performance testing commonly used to evaluate sports flooring systems, the length of the pad elements can also be easily adjusted to conform to the particular floor system involved. For example, the length of the largest pad element is generally preferably such that this pad element alone bears the lightest load on the system, i.e., the weight of the system itself. The next-smaller pad elements are then adjusted to help bear the increased loads from athletes performing on the floor, while the smallest pad elements would help bear the largest loads, such as from a large number of athletes or from heavy equipment.
The invention also includes a flooring system employing the resilient pads described above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the resilient pad of the present invention;
FIG. 2 is a sectional view of a portion of a floor system employing resilient pads of the present invention;
FIG. 3 is a side view of the resilient pad of FIG. 1, shown under light load conditions;
FIG. 4 is a side view of the resilient pad of FIG. 1, shown under moderate load conditions; and
FIG. 5 is a side view of the resilient pad of FIG. 1, shown under heavy load conditions.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The resilient pad 2 of the preferred embodiment is shown in FIG. 1. As shown therein, the pad is made up of a plurality of pad elements 11-13 connected together by a base 10. The pad elements 11-13 are cylindrical in shape, and are each connected along a narrow strip 15 to the base 10. The pad elements are preferably attached to the base during extrusion of the resilient pad. The strip 15 is preferably kept as narrow as possible so as to allow for deformation of the pad elements around the area of the base 10, as will be hereinafter described.
The pad elements are preferably attached such that their longitudinal axes are generally parallel to each other, and are also generally parallel to the floor (see FIG. 2). As shown in FIG. 1, pad element 11 is preferably located generally in the center of the base 10, and has a greater diameter than the other pad elements. Two pad elements 12 are located one on either side of pad element 11, and are of lesser diameter than pad element 11. Two pad elements 13 are located one on either side of pad element 12, and are of lesser diameter than both pad elements 11 and 12.
The pad elements can be made out of a variety of resilient materials, such as natural rubber, PVC, neoprene, nylon, or polyurethane. The pad elements preferably all have the same durometer generally in the range of 40-70, with values of 50 to 60 being most preferred. Base 10 is preferably made out of the same material as the pad elements.
A typical floor system with which the resilient pad of the present invention can be used is shown in FIG. 2. This floor system is made up of flooring 18 attached to a subfloor 19. Flooring 18 is generally made up of hardwood floor strips which are connected together by a tongue and groove arrangement. Subfloor 19 is commonly made up of two layers of plywood 22 connected together by staples 23. Flooring 18 is preferably attached to the subfloor by way of staples or nails 20 driven in above the tongue of the floor strips.
Also shown in FIG. 2 is the substrate 17 over which the flooring system is laid. Substrate 17 is typically a concrete layer or the like.
Two resilient pads 2 made according to the present invention are shown in FIG. 2. The pads are disposed between the subfloor 19 and the substrate 17. The base 10 of the resilient pad is preferably thick enough to provide sufficient durability that the pads can be attached to the underside of subfloor 19 by way of staples 25. The preferred thickness of the base is approximately 1/8 of an inch. Alternatively, the resilient pads may be attached by other means, such as by gluing.
FIG. 3 shows the effect of light loads, such as the weight of the floor system itself, on the resilient pads. As seen in FIG. 3, only the largest pad element 11 compresses under such loading. The compression occurs primarily along the top 28 and bottom 29 of the pad element. The adjacent pad elements 12 and 13 are preferably not compressed at all under such light load conditions.
FIG. 4 shows the effects of increased loading on the resilient pads. The largest pad element 11 continues to compress, while the next-largest pad elements 12 also begin to bear some of the load and compress. Again, the compression occurs primarily along the top 28 and bottom 29 of the pad elements. The outer pad elements 13 are not yet compressed.
FIG. 5 shows the resilient pad under full loading. Such loading would occur when a number of athletes converge on one area of the floor, or when heavy objects, such as bleachers, are placed on the floor. Each of the pad elements is compressed under the heavy load.
The amount of resiliency provided by the pad is directly related to the length of the pad elements 11-13. The optimum length for the pad elements used in a particular flooring system can be determined by performance testing. Because the resilient pad of the present invention has a uniform longitudinal cross-section, the material for the reslient pads can be formed in long lengths by extrusion. The individual resilient pads are then simply cut to the desired length. In a standard system such as the one shown in FIG. 2, the preferred length for the resilient pads is around two inches.
Alternatively, the individual pad elements 11-13 can be extruded separately and then attached to the base 10. As a second alternative, although not preferred because of increased production costs, the resilient pads of the present invention can be formed in a mold. These alternative embodiments allow for variations in the construction of the resilient pad. For example, by these alternative embodiments, the various pad elements can be made of materials having different hardness, if desired.
The number and spacing of the resilient pads in the floor system can also affect the characteristics of the floor system. Again, optimum results can be achieved through performance testing with the particular floor system.
The foregoing constitutes a description of the preferred embodiment of the invention. Numerous modifications are possible without departing from the spirit and scope of the invention. For example, the pad elements need not be circular in cross-section, but can have different cross-sectional shapes. All of the pad elements need not be of the same hardness, nor need they be made of the same material. More or less pad elements than the number shown in the preferred embodiment may be provided, and the pad elements can be provided in more or less than the three different thicknesses as shown. The size and relative dimensions of the various elements can be varied where appropriate. The invention need not be used with the floor system shown in FIG. 2, but can be used with floor systems of various types.
Hence, the scope of the invention should be determined with reference, not to the preferred embodiment, but to the appended claims. | The invention is a resilient pad for placement under a floor system. The pad is made up of a base and a plurality of pad elements spaced longitudinally apart and attached to the base. At least one of the pad elements has a thickness which is greater than another of the pad elements. Because the pad elements have different thicknesses, the resilient pad provides desirable response and shock-absorption characteristics over a wide range of applied loads. Hence, the resilient pad is especially suitable for use with sports floors and the like. | 4 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is in the field of prostaglandin and analog drugs. More particularly the present invention is in the field of prostaglandin analog drugs which are used for treatment of ocular hypertension, glaucoma or have other useful pharmacological properties. Still more particularly, the present invention is directed to pro-drugs of prostaglandin analogs which are used for treatment of ocular hypertension, glaucoma, have beneficial effects on platelet congregation, gastric ulceration, blood pressure regulation and inflammation.
[0003] 2. Background Art
[0004] Several prostaglandin analogs are presently known for their ability to reduce intraocular pressure and can be used for treatment of glaucoma and related diseases of the eye. Among these the drugs known by the names Bimatoprost (U.S. Pat. No. 5,688,819) Latanoprost (U.S. Pat. Nos. 4,599,353, 5,296,504, 5,422,368), Unoprostone (U.S. Pat. No. 6,329,426) and Travoprost (U.S. Pat. Nos. 5,631,287, 5,849,792, 5,889,052, 6,011,062) are mentioned as important ones in current use, and are shown by chemical structure below. The conventional numbering of prostaglandins and like structures is indicated in connection with the formula of Bimatoprost.
SUMMARY OF THE INVENTION
[0005] In accordance with the present invention 9,11 cycloendoperoxide derivatives of biologically active prostaglandin analogs comprise pro-drugs which hydrolyze under physiological conditions to provide prostaglandin analogues that are capable of providing sustained ocular and other in vivo concentrations of biologically active prostaglandin analogues. See Fredholm et al., Prostaglandins 1976, 11, 507-518 and Stringfellow et al., Prostaglandins 1978, 16, 901-910).
[0006] The 9,11-cycloendoperoxide analogs of biologically active prostaglandins are, generally speaking, chemically stable and are converted to the active drugs Bimatoprost, Latanaprost, Unoprostone, Travoprost, and H 2 1-ethanolamide or to structurally closely related analogs, as well as into other biologically active prostglandins, such as prostaglandins D 2 , E 2 , and F 2alpha , thromboxane and prostacyclin analogs, with ocular hypotensive and other biological activity. The thromboxane and prostacyclin analogues effect platelet aggregation and are expected to play a crucial role in preventing gastric ulceration by inhibiting gastric acid secretion, in blood pressure regulation by control of vascular tone, and in inflammation by inhibiting protease secretion of polymorphonuclear leucocytes.
[0007] In addition to being useful as pro-drugs which hydrolyze under physiologic condition to the corresponding drugs, the 9,11-cycloendoperoxides of the invention may per se have the biological activity of the corresponding drug into which they hydrolyze, and as such are expected to provide still better sustained physiological concentration of the therapeutic agent which they represent.
[0008] The 9,11-cycloendoperoxide pro-drugs of the present invention, in addition to undergoing hydrolysis to provide the corresponding biologically active prostaglandin analogs, also act as substrates to several naturally occurring enzymes which convert the 9,11-cycloendoperoxide pro-drugs into other biologically active analogs wherein the molecular structure is modified. These enzymatic reactions which occur in vivo can also be performed in vitro by utilizing the corresponding enzymes isolated from human or other mammalian organisms, and are illustrated below in Reaction Schemes 10 through 20.
[0009] The compounds of the invention are generally disclosed by Formula 1,
[0010] wherein the dashed lines represent the presence of a bond, or absence of a bond, wavy lines represent either alpha or beta configuration, solid triangles represent beta configuration and hatched lines represent alpha configuration;
[0011] n is an integer having the values of 1 to 6;
[0012] m is an integer having the values of 1 to 8;
[0013] X is NH 2 , N(R) 2 , NHR, or OR where R is hydrogen, R 4 or a (CO)R 4 group;
[0014] Y is ═O, ═S or OH, OR 5 or —O(CO)R 5 groups, said OH, OR 5 or O(CO)R 5 groups being attached to the adjacent carbon in alpha or beta configuration;
[0015] R 1 is H, CH 3 , R 7 , OR 7 or SR 7 where R 7 is an aliphatic, aromatic or heteroaromatic ring, said heteroaromatic ring having 1 to 3 heteroatoms selected from O, S, and N, said aliphatic, aromatic or heteroaromatic ring being optionally substituted with 1 to 3 R 8 groups where R 8 is F, Cl, Br, I, NO 2 , C 1-6 alky, C 1-6 fluoro substituted alkyl, COOH, or COOR 9 where R 9 is alkyl of 1 to 6 carbons or CH 2 OCH 3 ;
[0016] R 2 and R 3 together represent ═O, ═S, or independently are hydrogen or alkyl of 1 to 6 carbon atoms;
[0017] R 4 represents (CH 2 ) r OH, (CH 2 ) r OCOR 9 or (CH 2 ) r OR 9 where r is an integer having the values 1 to 6, or R 4 represents saturated or unsaturated acyclic hydrocarbons having from 1 to 20 carbon atoms, or —(CH 2 ) q R 6 where q is 0-10 and R 6 is an aliphatic, aromatic or heteroaromatic ring, said heteroaromatic ring having 1 to 3 heteroatoms selected from O, S, and N, said aliphatic, aromatic or heteroaromatic ring being optionally substituted with 1 to R 8 groups where R 8 is F, Cl, Br, I, NO 2 , C 1-6 alky, C 1-6 fluoro substituted alkyl, COOH, COOR 9 where R 9 is alkyl of 1 to 6 carbons or CH 2 OCH 3 ;
[0018] R 5 represents saturated or unsaturated acyclic hydrocarbons having from 1 to 20 carbon atoms, or —(CH 2 ) q R 6 , or a pharmaceutically acceptable salt of said compound.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Definitions:
[0020] As used herein the term alkyl refers to and covers any and all groups which are known as normal alkyl, branched-chain alkyl, cycloalkyl and also cycloalkyl-alkyl. The term alkenyl refers to and covers normal alkenyl, branch-chained alkenyl and cycloalkenyl groups having one or more sites of unsaturation. When referring to saturated or unsaturated acyclic hydrocarbons, the term covers normal alkyl, normal alkenyl and normal alkynyl groups as well as branch-chained alkyl, branch-chained alkenyl and branch-chained alkynyl groups, the normal and branch-chained alkenyl and alkynyl groups having one or more sites of unsaturation.
[0021] A pharmaceutically acceptable salt may be prepared for any compound in this invention having a functionality capable of forming a salt, for example an acid or amine functionality. A pharmaceutically acceptable salt is any salt which retains the activity of the parent compound and does not impart any deleterious or untoward effect on the subject to which it is administered and in the context in which it is administered.
[0022] Pharmaceutically acceptable salts may be derived from organic or inorganic bases. The salt may be a mono or polyvalent ion. Of particular interest are the inorganic ions, sodium, potassium, calcium, and magnesium. Organic salts may be made with amines, particularly ammonium salts such as mono-, di- and trialkyl amines or ethanol amines. Salts may also be formed with caffeine, tromethamine and similar molecules. Where there is a nitrogen sufficiently basic as to be capable of forming acid addition salts, such may be formed with any inorganic or organic acids or alkylating agent such as methyl iodide. Preferred salts are those formed with inorganic acids such as hydrochloric acid, sulfuric acid or phosphoric acid. Any of a number of simple organic acids such as mono-, di- or tri-acid may also be used.
[0023] The compounds of the present invention are capable of existing as trans and cis (E and Z) isomers relative to the five-membered ring shown in the respective formulas, and relative to olefinic double bonds. Unless specific orientation of substituents relative to a double bond or the ring is indicated in the name of the respective compound, and/or by specific showing in the structural formula of the orientation of the substituents relative to the double bond or ring, the invention covers trans as well as cis isomers relative to each center that gives rise to such isomerism, as well as mixtures of trans and cis isomers.
[0024] The compounds of the present invention also contain one or more chiral centers and therefore may exist in enantiomeric and diastereomeric forms. Again, unless the name of a compound or its formula specifically describes or shows a specific enantiomer or diastereomer, the scope of the present invention is intended to cover all isomers per se, as well as mixtures of cis and trans isomers, mixtures of diastereomers and racemic mixtures of enantiomers (optical isomers) as well.
[0025] In the presently preferred compounds of the invention the variable n is 3, and the variable m is in the range or 1 to 6. The dotted line between carbons 5 and 6 as the numbering is shown on the structure depicting Bimatoprost, preferably represents a bond.
[0026] The variable Y preferably represents ═O or OH, or O(CO)R 5 , where R 5 is preferably alkyl of 1 to 6 carbons. Even more preferably Y is OH attached to the adjacent carbon with a bond of alpha orientation.
[0027] In the presently preferred compounds of the invention R 1 is methyl, phenyl, phenyl substituted in the phenyl group in the manner described in connection with Formula 1, or R 1 is O-phenyl, or O-phenyl substituted in the phenyl group in the manner described in connection with Formula 1. When R 1 is O-phenyl substituted in the phenyl group then the presently most preferred substituent is trifluoromethyl.
[0028] With respect to the group shown as C(X)(R 2 )(R 3 ) in Formula 1 the R 2 and R 3 groups preferably jointly form an oxo (═O) function, and the variable X is preferably OH, OR 4 or NHR 4 . R 4 is preferably alkyl of 1 to 6 carbons, or (CH 2 ) r OH where most preferably r is an integer having the value 2.
[0029] The presently most preferred compounds of the invention are the 9,11-cycloendoperoxide pro-drugs structurally closely related to Bimatoprost, Latanapost, Unoprostone, Travoprost, Bimatoprost acid and of Prostaglandin H 2 1-ethanolamide, the chemical structures of which are provided below. Although these structures show specific examples, they nevertheless generally show the 9,11-cycloendoperoxide moiety which can be introduced into the biologically active prostaglandin analogs by the enzymatic synthetic methods described below in detail. Numbers in parentheses next to the 9,11-cycloendoperoxides illustrated below refer to the specific compound numbers which are utilized in the specific description of examples and corresponding reaction schemes.
[0030] The enzymatic methods utilize the enzyme human COX-2 which can be obtained commercially from Cayman Chemical (Ann Arbor, Mich.). It was cloned in as described by Hla et al. in Proc. Natl. Acad. Sci. USA 1992, 89: 7384-7388, incorporated herein by reference. The enzyme was prepared by expression of a DNA clone encoding this enzyme in Baculovirus overexpression system in insect host cells (Sf21 cells).
[0031] The compounds on which the enzymatic syntheses utilizing the enzyme human COX-2 are performed can be prepared by chemical reactions and/or a combination of chemical and enzymatic reactions which are illustrated below, and by such modifications and adaptation of the chemical and/or enzymatic reactions which are within the skill of the practicing synthetic chemist in light of the present disclosure combined with general knowledge and available scientific and patent literature.
Biological Activity, Modes of Administration
[0032] The compounds of the invention are primarily active as pro-drugs of biologically active prostaglandins or prostaglandin analogs. Because the compounds act primarily as pro-drugs their ultimate biological effect is substantially the same as that of the corresponding drug. However, because the compounds of the invention act as pro-drugs, they tend to release the corresponding drug over a period of time, and therefore are expected to act as a sustained release drug, capable of maintaining a therapeutically effective concentration of the corresponding drug for a longer period of time than the corresponding drug. Still speaking generally, pro-drugs of the present invention are likely to be administered in the same manner as the corresponding drug, and in doses comparable to the administration of the corresponding drug. For specific description of modes of administration and dosages of the known prostaglandin drugs for which the 9,11-cycloendoperoxide compounds of the invention serve as pro-drugs, reference is made to the state of the art and to U.S. Pat. Nos. 5,688,819; 5,296,504; 4,599,353; 5,422,368; 6,329,426, 5,631,287, 5,849,792, 5,889,052 and 6,011,062 the specification of all which is incorporated herein by reference.
[0033] The pro-drugs of the present invention may also be administered in combination with the corresponding drug.
[0034] An important application of several pro-drugs in accordance with the present invention is treatment of ocular hypertension or glaucoma. For this purpose, similarly to the corresponding drug, such as Bimatoprost, Latanaprost, Unoprostone, Travoprost and prostaglandin H 2 1-ethanolamide, the pro-drug is preferably administered as a topical ophthalmic solution.
[0035] Still speaking generally, pharmaceutical compositions may be prepared by combining a therapeutically effective amount of at least one compound according to the present invention, or a pharmaceutically acceptable salt thereof, as an active ingredient, with conventional pharmaceutical excipients, and in some cases by preparation of unit dosage forms suitable for specific use, such as topical ocular use. The therapeutically efficient amount typically is between about 0.0001 and about 5% (w/v), preferably about 0.001 to about 1.0% (w/v) in liquid formulations.
[0036] For ophthalmic application, preferably solutions are prepared using a physiological saline solution as a major vehicle. The pH of such ophthalmic solutions should preferably be maintained between 6.5 and 7.2 with an appropriate buffer system. The formulations may also contain conventional, pharmaceutically acceptable preservatives, stabilizers and surfactants.
[0037] Preferred preservatives that may be used in the pharmaceutical compositions of the present invention include, but are not limited to, benzalkonium chloride, chlorobutanol, thimerosal, phenylmercuric acetate and phenylmercuric nitrate. A preferred surfactant is, for example, Tween 80. Likewise, various preferred vehicles may be used in the ophthalmic preparations of the present invention. These vehicles include, but are not limited to, polyvinyl alcohol, povidone, hydroxypropyl methyl cellulose, poloxamers, carboxymethyl cellulose, hydroxyethyl cellulose and purified water.
[0038] Tonicity adjustors may be added as needed or convenient. They include, but are not limited to, salts, particularly sodium chloride, potassium chloride, mannitol and glycerin, or any other suitable ophthalmically acceptable tonicity adjustor.
[0039] For ophthalmic use various buffers and means for adjusting pH may be used so long as the resulting preparation is ophthahnically acceptable. Accordingly, buffers include acetate buffers, citrate buffers, phosphate buffers and borate buffers. Acids or bases may be used to adjust the pH of these formulations as needed.
[0040] In a similar vein, an ophthalmically acceptable antioxidant for use in the present invention includes, but is not limited to, sodium metabisulfite, sodium thiosulfate, acetylcysteine, butylated hydroxyanisole and butylated hydroxytoluene.
[0041] Other excipient components which may be included in the ophthalmic preparations are chelating agents. The preferred chelating agent is edetate disodium, although other chelating agents may also be used in place or in conjunction with it.
[0042] The ingredients are usually used in the following amounts:
Ingredient Amount (% w/v) active ingredient about 0.001-5 preservative 0-0.10 vehicle 0-40 tonicity adjustor 1-10 buffer 0.01-10 pH adjustor q.s. pH 4.5-7.5 antioxidant as needed surfactant as needed purified water as needed to make 100%
[0043] The actual dose of the active compounds of the present invention depends on the specific compound, and on the condition to be treated; the selection of the appropriate dose is well within the knowledge of the skilled artisan.
[0044] The ophthalmic formulations of the present invention may be conveniently packaged in forms suitable for metered application, such as in containers equipped with a dropper, to facilitate the application to the eye. Containers suitable for drop-wise application are usually made of suitable inert, non-toxic plastic material, and generally contain between about 0.5 and about 15 ml solution.
DESCRIPTION OF SPECIFIC EMBODIMENTS AND EXAMPLES
[0045] General Procedure A
[0046] Chemical Synthesis of Arachidonyl Ethanolamide (Compound 2)
[0047] The chemical synthesis of arachidonyl ethanolamide from arachidonic acid (Compound 1) is illustrated in Reaction Scheme 1. Arachidonyl ethanolamide (Compound 2) is synthesized following a literature procedure of Abadji et al., J. Med. Chem. 1994, 37, 1889-1893, incorporated herein by reference. To a 0.1 M solution of arachidonic acid (Compound 1, available from Cayman Chemical) in anhydrous benzene at 0° C. is added one equivalent of anhydrous dimethyl formamide and two equivalents of oxalyl chloride. The reaction is stirred at room temperature for 1 h and an equal volume of anhydrous tetrahydrofuran (THF) is added. The mixture is then cooled to 0° C. and a 1 M solution of 10 equivalents 2-amino-ethanol in anhydrous THF is added. The reaction is stirred at room temperature until completion. The reaction mixture is then diluted with chloroform, washed successively with 1 M HCl, 1 M NaOH, brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product is purified by chromatography on silica gel. Arachidonyl ethanolamide (Compound 2) is enzymatically converted into the corresponding 9,11-cycloendoperoxide derivative as shown in Reaction Scheme 3 and is described below.
[0048] Chemical Synthesis of Compound 3
[0049] The chemical synthesis of Compound 3 from arachidonic acid (Compound 1) is also illustrated in Reaction Scheme 1. Compound 3 is synthesized by modification of procedures reported by Ryan et al. J. Med. Chem. 1997, 40, 3617-3625, based on previous work by Corey et al. Tetrahedron Lett. 1983, 24, 37-40 and Manna et al. Tetrahedron Lett. 1983, 24, 33-36. The Ryan et al., Corey et al., and Manna et al. publications are hereby expressly incorporated by reference. To a 0.4 M solution of arachidonic acid (Compound 1) in anhydrous benzene at 0° C. are added two equivalents of oxalyl chloride. The mixture is stirred for overnight while allowed to warm to room temperature. The solvent and excess oxalyl chloride is removed in vacuo. The resulting crude acid chloride is dissolved in anhydrous THF to make a ˜2 M solution. Half an equivalent of pyridine is added to the above solution and the mixture is stirred for 10 min at 0° C. 0.7 M solution of LiOH.H 2 O in 50% H 2 O 2 containing one equivalent of LiOH.H 2 O is added and the mixture is stirred for 20 min. The reaction is quenched with pH 7 buffer and brine and extracted with CH 2 Cl 2 (×3). The combined organic layer is washed with brine and dried over Na 2 SO 4 . During this time the epoxy acid is formed and its formation can be monitored by TLC analysis. Upon completion, the drying agent is removed by filtration and the solvent is removed in vacuo. The residue is dissolved in anhydrous Et 2 O and treated with excess diazomethane. After stirring for 15 min, excess diazomethane is evaporated in a fume hood at room temperature and the solvent is removed in vacuo. The crude product is purified by chromatography on silica gel.
[0050] Chemical Synthesis of Compound 4
[0051] The chemical synthesis of Compound 4 from Compound 3 is also illustrated in Reaction Scheme 1. Compound 4 is synthesized following procedures reported by Ryan et al. J. Med. Chem. 1997, 40, 3617-3625. A 0.05 M solution of Compound 3 in TIHF—H 2 O (2:1) is treated with five equivalents of 1.2 M HClO 4 at room temperature for overnight. The reaction mixture is then quenched with pH 7 buffer and extracted with EtOAc (×3). The combined organic layer is washed with brine, dried over Na 2 SO 4 , and concentrated in vacuo. The residue is purified by chromatography on silica gel.
[0052] Chemical Synthesis of Compound 5
[0053] The chemical synthesis of Compound 5 from Compound 4 is also illustrated in Reaction Scheme 1. Compound 5 is synthesized following procedures reported by Ryan et al. J. Med. Chem. 1997, 40, 3617-3625. A 0.2 M solution of Compound 4 in CH 2 Cl 2 at −20° C. is treated with one equivalent of lead (IV) tetraacetate (0.2 M solution in CH 2 Cl 2 ) for 0.5 h. The reaction mixture is filtered through a pad of celite-silica gel and washed with hexane. The solvent is removed in vacuo to afford Compound 5 which is unstable and is used immediately in the next reaction.
[0054] General Procedure B
[0055] Chemical Synthesis of Compound 6
[0056] The chemical synthesis of Compound 6 from Compound 5 is also illustrated in Reaction Scheme 1. Compound 6 is synthesized by Wittig olefination of Compound 5 with the ylide triphenyl-(3-phenylpropylidene)-δ 5 -phosphane. The ylide is generated by adding one equivalent of n-butyllithium to a 0.3M solution of triphenyl-(3-phenyl-propyl)phosphonium bromide (available from Lancaster) in THF at −78° C. After stirring for 30 min, 0.7 equivalent of Compound 5 in THF is added and the reaction is warmed to room temperature and stirred for 1 h. After completion, the reaction is diluted with hexane, washed successively with pH 7 buffer, brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product is purified by chromatography on silica gel.
[0057] General Procedure C
[0058] Chemical Synthesis of Compound 7
[0059] The chemical synthesis of Compound 7 from Compound 6 is also illustrated in Reaction Scheme 1. A mixture of Compound 6 and 7 equivalents of lithium hydroxide monohydrate in methanol-water (3:1) is heated to 50° C. until the reaction is complete by TLC analysis. The reaction mixture is cooled to room temperature, quenched with aqueous NH 4 Cl and extracted with ethyl acetate (x3). The combined organic layer is washed with H 2 O, brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product is purified by chromatography on silica gel. Compound 7 is enzymatically converted into the corresponding 9,11-cycloendoperoxide derivative as shown in Reaction Scheme 4 and is described below.
[0060] Chemical Synthesis of Compound 8
[0061] Compound 8 is synthesized following General Procedure A, using ethyl amine instead of 2-amino-ethanol, as illustrated in Reaction Scheme 1. Compound 8 is enzymatically converted into the corresponding 9,11-cycloendoperoxide derivative as shown in Reaction Scheme 5 and is described below.
[0062] Chemical Synthesis of Compound 9
[0063] Compound 9 is synthesized following General Procedure A, using isopropyl alcohol instead of 2-amino-ethanol, as illustrated in Reaction Scheme 1. Compound 9 is enzymatically converted into the corresponding 9,11-cycloendoperoxide derivative as shown in Reaction Scheme 6 and is described below.
[0064] Chemical Synthesis of Compound 10
[0065] Compound 10 is synthesized by Wittig olefination following General Procedure B, using Compound 5 and (n-octyl)triphenylphosphonium bromide (available from Lancaster) instead of triphenyl-(3-phenyl-propyl)phosphonium bromide, as illustrated in Reaction Scheme 2.
[0066] Chemical Synthesis of Compound 11
[0067] Compound 11 is synthesized in a three step sequence following General Procedure C and General Procedure A, using isopropyl alcohol instead of 2-amino-ethanol as illustrated in Reaction Scheme 2. Compound 11 is enzymatically converted into the corresponding 9,11-cycloendoperoxide derivative as shown in Reaction Scheme 7 and is described below.
[0068] Chemical Synthesis of Compound 12
[0069] Compound 12 is synthesized from Compound 5 following procedures reported by Seltzman (Seltzman et al. J. Med. Chem. 1997, 40, 3626-3634) and Razdan (Dasse et al. Tetrahedron 2000, 56, 9195-9202), as illustrated in Reaction Scheme 2. To a 0.25 M solution of Compound 5 in methanol at 0° C. is added 2 equivalents of NaBH 4 . The reaction is warmed to room temperature and is monitored by TLC analysis. After completion, the reaction is quenched with aqueous NH 4 Cl and is extracted with EtOAc (×3). The combined organic layer is washed with H 2 O, brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product alcohol is purified by chromatography on silica gel. This intermediate alcohol is then converted to Compound 12 following Razdan's procedures (Dasse et al. Tetrahedron 2000, 56, 9195-9202.) 1.1 equivalent of 12 is added portion-wise to a solution of 1.1 equivalent of triphenylphosphine and 1.1 equivalent of imidazole in Et 2 O—CH 3 CN (3:1) at 0° C. The mixture is stirred at room temperature for 20 min, cooled to 0° C. To this mixture is added the intermediate alcohol and the reaction is stirred at room temperature for 1 h. The reaction is then diluted with pentane-Et 2 O (4:1), filtered through a pad of silica gel to afford Compound 12.
[0070] Chemical Synthesis of Compound 13
[0071] Compound 13 is synthesized from Compound 12 following procedures reported by Razdan (Ryan et al. J. Med. Chem. 1997, 40, 3617-3625; and Dasse et al. Tetrahedron 2000, 56, 9195-9202), as illustrated in Reaction Scheme 2. A 0.2 M solution of Compound 12 and 1.1 equivalent of triphenylphosphine in CH 3 CN is heated to reflux until completion of the reaction. The solvent is removed in vacuo and the residue is purified by washing with hexane-benzene (1:1). The product is dried in a vacum oven and used directly in the next Wittig reaction.
[0072] Chemical Synthesis of Compound 14
[0073] The chemical synthesis of Compound 14 is illustrated in Reaction Scheme 2. To a 0.3 M solution of Compound 13 in THF at −78° C. is added 1 equivalent of potassium bis(trimethylsilyl)amide (available from Aldrich). The mixture is stirred at −78° C. for 30 min. A solution of 1.5 equivalent of (3-trifluoromethyl-phenoxy)-acetaldehyde (prepared by reducing 3-(trifluoromethyl)phenoxyacetonitrile (available from Lancaster) with diisobutylaluminum hydride) in THF is added dropwise to the above mixture and the reaction is gradually warmed to room temperature. Upon completion, the reaction is diluted with heaxans, washed with pH 7 buffer, brine, dried over Na 2 SO 4 , and concentrated in vacuo. The crude product is purified by chromatography on silica gel.
[0074] Chemical Synthesis of Compound 15
[0075] Compound 15 is synthesized from Compound 14 following General Procedure C as illustrated in Reaction Scheme 2. Compound 15 is enzymatically converted into the corresponding 9,11-cycloendoperoxide derivative as shown in Reaction Scheme 8 and is described below.
[0076] Chemical Synthesis of Compound 16
[0077] Compound 16 is synthesized from Compound 14 following General Procedure A, using isopropyl alcohol instead of 2-aminoethanol, as illustrated in Reaction Scheme 2. Compound 16 is enzymatically converted into the corresponding 9,11-cycloendoperoxide derivative as shown in Reaction Scheme 9 and is described below.
[0078] General Procedure D
[0079] Enzymatic Synthesis of 9,11-cycloendoperoxide of Prostaglandin H 2 1-ethanolamide (Compound 17)
[0080] The human COX-2 catalyzed biosynthesis of Prostaglandin H 2 1-ethanolamide 9,11-cycloendoperoxide (Compound 17) from its arachidonyl ethanolamide (Compound 2) is illustrated in Reaction Scheme 3. The enzyme human COX-2 was obtained commercially from Cayman Chemical (Ann Arbor, Mich.). It was cloned in 1992 (see the publication by Hla et al. supra). The enzyme was prepared by expression of a DNA clone encoding this enzyme in Baculovirus overexpression system in insect host cells (Sf1 cells). Ten μM [ 3 H]arachidonyl ethanolamide (Compound 2) with a specific activity of 860 μCi/7 mg in 20 μl of ethanolic solution was diluted with 960 μl of the COX-2 (hCOX-2) reaction buffer (100 mM Tris-HCl, pH 8.0, containing 2 mM phenol, 5 μM hematin and 1 mM EDTA). One hundred units of hCOX-2 enzyme preparation in 20 μl of hCOX-2 buffer were added to start enzyme reaction. The total incubation volume was 1 ml. The enzyme reaction was stopped by adding 1 ml dry ice-cooled stop solution (ether: methanol: 1 M acetic acid, 30:4:1, v/v) immediately after incubation at 37° C. for 2 minutes. The synthesized products were extracted two times with 3 ml of ethyl acetate each. The organic phase was collected and dried at room temperature under nitrogen. The resulting residue was reconstituted in 150 μl of acetonitrile/water (1:1, v/v) for HPLC-Radiometric analysis and LC/MS/MS analysis. The LC/MS/MS analysis of the synthesized 9,11-cycloendoperoxide of prostaglandin H 2 1-ethanolamide eluting at 31.6 minutes indicated that its molecular weight was 395 daltons. The yield of the synthesis as determined by HPLC-Radiometric analysis was 30%.
[0081] Enzymatic Synthesis of Bimatoprost Acid 9,11-cycloendoperoxide (Compound 18)
[0082] Bimatoprost acid 9,11-cycloendoperoxide (Compound 18) is synthesized following General Procedure D using Compound 7, instead of arachidonyl ethanolamide (Compound 2), as illustrated in Reaction Scheme 4.
[0083] Enzymatic Synthesis of Bimatoprost 9,11-cycloendoperoxide (Compound 19)
[0084] Bimatoprost 9,11-cycloendoperoxide (Compound 19) is synthesized following General Procedure D using Compound 8 instead of arachidonyl ethanolamide (Compound 2) as illustrated in Reaction Scheme 5.
[0085] Enzymatic Synthesis of Latanoprost 13,14-dehydro-9,11-cycloendoperoxide (Compound 20)
[0086] Latanoprost 13,14-dehydro-9,11-cycloendoperoxide (Compound 20) is synthesized following General Procedure D using Compound 9 instead of arachidonyl ethanolamide (Compound 2), as illustrated in Reaction Scheme 6.
[0087] Enzymatic Synthesis of Unoprostone 15-hydroxy-9,11-cycloendoperoxide (Compound 21)
[0088] Unoprostone 15-hydroxy-9,1-cycloendoperoxide (Compound 21) is synthesized following General Procedure D using Compound 11 instead of arachidonyl ethanolamide (Compound 2) as illustrated in Reaction Scheme 7.
[0089] Enzymatic Synthesis of Travoprost 9,11-cycloendoperoxide (Compound 22)
[0090] Travoprost 9,11-cycloendoperoxide (Compound 22) is synthesized following General Procedure D using Compound 15 instead of arachidonyl ethanolamide (Compound 2) as illustrated in Reaction Scheme 8.
[0091] Enzymatic Synthesis of Travoprost acid 9,11-cycloendoperoxide (Compound 23)
[0092] Travoprost acid 9,11-cycloendoperoxide (Compound 23) is synthesized following General Procedure D using Compound 16 instead of arachidonyl ethanolamide (Compound 2) as illustrated in Reaction Scheme 9.
[0093] As noted above in the Summary section of the present application for patent, the 9,11-cyclopendoperoxide pro-drugs of the present invention, in addition to undergoing hydrolysis to provide the corresponding biologically active prostaglandin analogs, also act as substrates to several naturally occurring enzymes which convert the 9,11-cyclopendoperoxide pro-drugs into other biologically active analogs. Several of these enzymatic reactions which are expected to occur in vivo can be performed in vitro in accordance with the present invention resulting in the enzymatic synthesis from the 9,11-cycloendoperoxides of the invention of several biologically active prostaglandin analogs. These enzymatic reactions are illustrated below in Reaction Schemes 10 through 20.
[0094] General Procedure E
[0095] Enzymatic Synthesis of Prostaglandin F 2α 1-ethanolamide (Compound 24)
[0096] The human recombinant PGF synthase catalyzed biosynthesis of Prostaglandin F 2α 1-ethanolamide from prostaglandin H 2 1-ethanolamide 9,11-cycloendoperoxide (Compound 17) is illustrated above in Reaction Scheme 10. 4.5 μM [ 3 H]Prostaglandin H 2 1-ethanolamide with a specific activity of 860 mCi/7 mg reconstituted in 0.6 ml of PGF synthase reaction buffer was incubated with 100 μl of the human recombinant PGF synthase solution (1.5 mg/ml) at 37° C. for 10 minutes. The cDNA clone of human PGF synthase was isolated from human lung and its enzyme was prepared by expression of cDNA clones in E. coli as described in the publication by Suzuki-Yamamoto et al., FEBS lett, 1999,462: 335-340, incorporated herein by reference. The plasmid was transformed into DH5 α E. coli strain and grown in LB/ampicillin medium. The expressed enzyme in E. coli was partially purified to yield a protein concentration of 15 mg per ml. The pUC8 vectors carrying no PGF synthase DNA insert were also transformed and prepared with protein concentration of 5 mg per ml as a negative control. The enzyme reaction was stopped by adding 1 ml dry ice-cooled stop solution (ether: methanol: 1 M acetic acid, 30:4:1, v/v) immediately after incubation at 37° C. for 10 minutes. The synthesized products were extracted with 3 ml of ethyl acetate. The organic phase was collected and dried at room temperature under nitrogen. The resulting residue was reconstituted in 150 μl of acetonitrile/water (1:1, v/v) for IHPLC-Radiometric analysis and LC/MS/MS analysis. The prostaglandin H 2 1-ethanolamide 9,11-cycloendoperoxide was completely converted to prostaglandin F 2α 1-ethanolamide in 10 minutes. The product ion spectrum of m/z 398.4 of the biosynthetic product was identical to the standard prostaglandin F 2α 1-ethanolamide. They both had the major characteristic fragment ion at m/z 62, which represents protonated 2-amino ethanol group. There was no conversion by the enzyme preparation from same DH5 α cells carrying pUC8 vector without PGF synthase DNA insert. The yield of the synthesis, as determined by HPLC-Radiometric analysis, was 94%.
[0097] General Procedure F
[0098] Enzymatic Synthesis of Prostaglandin E 2 1-ethanolamide (Compound 25)
[0099] Prostaglandin E 2 1-ethanolamide is synthesized from prostaglandin H 2 1-ethanolamide 9,11-cycloendoperoxide (Compound 17) following General Procedure E using the human recombinant PGE synthase obtained in accordance with the publication of Jakobsson et al. Proc. Natl. Acad. Sci. USA, 1999, 96: 7220-7225, incorporated herein by reference, instead of the human recombinant PGF synthase, as illustrated in Reaction Scheme 11.
[0100] General Procedure G
[0101] Enzymatic Synthesis of Prostaglandin D 2 1-ethanolamide (Compound 26)
[0102] Prostaglandin D 2 1-ethanolamide is synthesized from its prostaglandin H 2 1-ethanolamide 9,11-cycloendoperoxide (Compound 17) following General Procedure E using the human recombinant PGD synthase obtained in accordance with the publication of Nagata et al. Proc. Natl. Acad. Sci. USA, 1991, 88: 4020-4024, incorporated herein by reference, instead of the human recombinant PGF synthase, as illustrated in Reaction Scheme 12.
[0103] General Procedure H
[0104] Enzymatic Synthesis of Thromboxane A) 1-ethanolamide (Compound 27)
[0105] Thromboxane A 2 1-ethanolamide is synthesized from prostaglandin H 2 1-ethanolamide 9,11-cycloendoperoxide (Compound 17) following General Procedure E using the human recombinant thromboxane synthase obtained in accordance with the publication of Miyata et al., Eur. J. Biochem, 1994, 224: 273-279, incorporated herein by reference, instead of the human recombinant PGF synthase, as illustrated in Reaction Scheme 13.
[0106] General Procedure I
[0107] Enzymatic Synthesis of Prostacyclin 1-ethanolamide (Compound 28)
[0108] Prostacyclin 1-ethanolamide is synthesized from prostaglandin H 2 1-ethanolamide 9,11-cycloendoperoxide (Compound 17) following General Procedure E using the human recombinant prostacyclin synthase obtained in accordance with the publication of Miyata et al., Biochem. Biophys. Res. Commun. 1994, 200: 1728-1734, instead of the human recombinant PGF synthase, as illustrated in Reaction Scheme 14. Enzymatic synthesis of Bimatoprost acid (Compound 29), its prostaglandin analogues E 2 and D 2 (Compounds 30-31), thromboxane analogue A 2 (Compound 32) and prostacyclin analogue (Compound 33)
[0109] Compounds 29-33 are synthesized starting with Bimatoprost acid 9,11-cycloendoperoxide (Compound 18), instead of prostaglandin H 2 1-ethanolamide (Compound 17), following General Procedures E, F, G, H and I, respectively, as illustrated in Reaction Scheme 15 below.
[0110] Enzymatic Synthesis of Bimatoprost (Compound 34), its prostaglandin analogues E 2 and D 2 (Compounds 35-36), Thromboxane Analogue A 2 (Compound 37) and Prostacyclin Analogue (Compound 38)
[0111] Compounds 34-38 are synthesized from Bimatoprost 9,11-cycloendoperoxide (Compound 19), instead of prostaglandin H 2 1-ethanolamide (Compound 17), following General Procedures E, F, G, H and I, respectively, as illustrated in Reaction Scheme 16 below.
[0112] Enzymatic Synthesis of 13,14-dehydro-Latanoprost (Compound 39), its Prostaglandin Analogues E 2 and D 2 (Compounds 40-41), Thromboxane Analogue A 2 (Compound 42) and Prostacyclin Analogue (Compounds 43)
[0113] Compounds 39-43 are synthesized from Latanoprost 13,14-dehydro-9,11-cycloendoperoxide (Compound 20), instead of prostaglandin H 2 1-ethanolamide, (Compound 17) following General Procedures E, F, G, H and I, respectively, as illustrated in Reaction Scheme 17 below.
[0114] Enzymatic Synthesis of 13,14-dehydro-15-hydro-Unoprostone (Compound 44), its Prostaglandin Analogues E 2 and D 2 (Compounds 45-46), Thromboxane Analogue A 2 (Compound 47) and Prostacyclin Analogue (Compound 48)
[0115] Compounds 44-48 are synthesized from Unoprostone 13,14-dehydro-15-hydroxy-9,11-cycloendoperoxide (Compound 21), instead of prostaglandin H 2 1-ethanolamide (Compound 17), following General Procedures E, F, G, H and I, respectively, as illustrated in Reaction Scheme 18 below.
[0116] Enzymatic Synthesis of Travoprost (Compound 49), its Prostaglandin Analogues E 2 and D 2 (Compounds 50-51), thromboxane analogue A 2 (Compound 52) and Prostacyclin Analogue (Compound 53)
[0117] Compounds 49-53 are Synthesized from Travoprost 9,11-cycloendoperoxide (Compound 22), instead of Prostaglandin H 2 1-ethanolamide (Compound 17), following General Procedures E, F, G, H and I, respectively, as illustrated in Reaction Scheme 19 below.
[0118] Enzymatic Synthesis of Travoprost acid (Compound 54), its Prostaglandin Analogues E 2 and D 2 (Compounds 55-56), Thromboxane Analogue A 2 (Compound 57) and Prostacyclin Analogue (Compounds 58)
[0119] Compounds 54-58 are synthesized from Travoprost acid 9,11-cycloendoperoxide (Compound 23), instead of prostaglandin H 2 1-ethanolamide (Compound 17), following General Procedures E, F, G, H and I, respectively, as illustrated in Reaction Scheme 20 below. | 9,11-Cycloendoperoxide derivatives of biologically active prostaglandin analogs, and particularly of the ocular hypotensive drugs Bimatoprost, Latanaprost, Unoprostone, Travoprost and prostaglandin H 2 1-ethanolamide or of structurally closely related analogs, are pro-drugs which hydrolyze under physiological conditions to provide prostaglandin analogues that are capable of providing sustained ocular and other in vivo concentrations of the respective drugs. The compounds of the invention have the formula shown below where the variables have the meaning defined in the specification. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is based on, and claims priority from Taiwan Application Serial Number 102125685, filed on Jul. 18, 2013, and claims the benefit of U.S. Provisional Application No. 61/813,445, filed on Apr. 18, 2013, the entirety of which are incorporated by reference herein.
TECHNICAL FIELD
The technical field relates to nano metal wire, and in particular, relates to a method for manufacturing the same.
BACKGROUND
Recently, nano technology is widely used in information technology, material technology, biotechnology, and the likes. When the size of a material is scaled down to nano scale, its properties will change according to its shape and size. For example, a silver nanorod or nanowire may have absorption peaks of longitudinal mode and traverse mode under surface plasmon resonance. The nanorod or nanowire with a larger aspect (length-diameter) ratio has a red-shifted absorption peak of longitudinal mode.
A silver nanowire or silver wire with a high aspect ratio has been disclosed by some research teams. However, the conventional silver nanowires have a length of several nanometers (nm) to several micrometers (μm), an aspect ratio of less than 1000 (or even less than 100), and low conductivity.
Accordingly, a novel method for preparing silver nanowires with high conductivity and a high aspect ratio is called-for.
SUMMARY
One embodiment of the disclosure provides a method of manufacturing a nano metal wire, comprising: putting a metal precursor solution in a core pipe of a needle; putting a polymer solution in a shell pipe of the needle, wherein the shell pipe surrounds the core pipe; applying a voltage to the needle while simultaneously jetting the metal precursor solution and the polymer solution to form a nano line on a collector, wherein the nano line includes a metal precursor wire surrounded by a polymer tube; chemically reducing the metal precursor wire of the nano line to form a nano line of a nano metal wire surrounded by the polymer tube; and washing out the polymer tube by a solvent.
One embodiment of the disclosure provides a nano line, comprising: a metal precursor wire; and a polymer tube surrounding the metal precursor wire, wherein the metal precursor wire comprises a metal compound and a chemically reducing agent.
One embodiment of the disclosure provides a nano metal wire, having an aspect ratio of greater than 1000, and a conductivity of between 10 4 S/m to 10 7 S/m.
A detailed description is given in the following embodiments with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The disclosure can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
FIG. 1 shows an electrostatic spinning apparatus for manufacturing nano metal wires in one embodiment of the disclosure;
FIG. 2 illustrates a cross-sectional view of a shell pipe and a core pipe of a needle in one embodiment of the disclosure;
FIG. 3 shows a nano line in one embodiment of the disclosure;
FIG. 4 shows a nano metal wire in one embodiment of the disclosure;
FIG. 5 shows absorption spectra of nano silver wires without annealing or after annealing for different periods of time in some embodiments of the disclosure;
FIG. 6 shows absorption spectra of nano silver wires left to stand at room temperature for different periods of time or annealing for different periods of time in some embodiments of the disclosure; and
FIG. 7 shows an XRD spectrum of nano silver wires in one embodiment of the disclosure.
DETAILED DESCRIPTION
In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.
In the disclosure, a nano metal wire having a high aspect ratio (e.g. greater than 1000) is formed by an electrostatic spinning apparatus. As shown in FIG. 1 , a polymer solution is put into a syringe 11 , and a metal precursor solution is put into a syringe 13 . The syringe 11 connects to a shell pipe 15 O of a needle 15 , and the syringe 13 connects to a core pipe 15 I of the needle 15 , respectively. As shown in FIG. 2 , the shell pipe 15 O and the core pipe 15 I are concentric cylinders. A voltage is then applied to the needle 15 while simultaneously jetting the metal precursor solution and the polymer solution from the needle 15 , thereby forming a nano line 17 on a collector 19 . As shown in FIG. 3 , the nano line 17 includes a metal precursor wire 17 A surrounded by a polymer tube 17 B. The described process of forming the nano line 17 is the so-called electrostatic spinning method.
In one embodiment, a solvent of the polymer solution is an organic solvent with high-polarity such as methanol or acetone, and the corresponding polymer is polyvinylpyrrolidone (PVP). In addition, a salt such as tetrabutyl ammonium phosphate (TBAP) or cetyltrimethylammonium bromide (CTAB) can be optionally added into the polymer solution. The salt may enhance the polarization degree of the electrostatic spinning, thereby reducing the polymer amount.
In one embodiment, the additive amount of the salt is of about 1 mg/mL to 100 mg/mL. Alternatively, a solvent of the polymer solution can be an organic solvent with low-polarity such as tetrahydrofuran (THF), toluene, or chloroform. In this case, the corresponding polymer can be polyacrylonitrile (PAN), polyvinyl alcohol (PVA), or ethylene vinyl alcohol (EVA). If the solvent of the polymer solution is an organic solvent with high-polarity, it can be washed out by water to meet environmentally friendly requirements after the forming of a nano metal wire. If the solvent of the polymer solution is an organic solvent with low-polarity, the polymer solution and the metal precursor solution will be immiscible when forming the nano metal wire having a high quality. In one embodiment, the polymer in the polymer solution has a concentration of about 100 mg/mL to 200 mg/mL.
In one embodiment, the metal precursor solution includes a metal compound and chemically reducing agent. The metal compound can be a silver compound (e.g. silver nitrate or silver oxide), platinum compound (e.g. platinum chloride or platinous oxide), gold compound (e.g. gold chloride or auric acid), or combinations thereof. The selection of the chemically reducing agent depends on the metal compound type. For example, when the metal compound is silver nitrate, the chemically reducing agent can be ethylene glycol. When the metal compound is silver oxide, the chemically reducing agent can be ammonium hydroxide. When the metal compound is platinum chloride, the chemically reducing agent can be hydrazine, sodium hydroborate, hydrogen, or alcohol. When the metal compound is gold chloride, the chemically reducing agent can be an aqueous solution of sodium citrate or Vitamin C. The metal compound concentration depends on the metal compound type. For example, the silver nitrate has a concentration of about 1 mg/mL to 100 mg/mL, and the silver oxide has a concentration of about 1 mg/mL to 100 mg/mL. The chemically reducing agent concentration depends on the chemically reducing agent type. For example, the ethylene glycol may directly serve as an organic solvent with high-polarity, and the ammonium hydroxide may have a concentration of about 1 wt % to 50 wt %.
In one embodiment, the core pipe 15 I of the needle 15 has a diameter of about 0.5 m to 2 mm, which is determined by the desired diameter of the nano metal wire. In one embodiment, the shell pipe 15 O and the core pipe 15 I of the needle 15 have a difference of about 0.01 mm to 5 mm.
In one embodiment, the voltage applied to the needle 15 is about 10 kV to 12 kV. In one embodiment, a tip of the needle 15 and the collector 19 have a distance therebetween of about 5 cm to 50 cm. If the collector 19 is a common plate, random arranged nano lines 17 will be easily formed. If the collector 19 is parallel electrode plate, parallel arranged nano lines 17 will be formed.
In one embodiment, the syringes 11 and 13 are controlled by syringe pumps 12 and 14 , respectively, to tune flow rates of the polymer solution and the metal precursor solution. For example, the polymer solution is jetted out of the needle 15 with a flow rate of about 0.1 mL/hr to 5 mL/hr, and the metal precursor solution is jetted out of the needle 15 with a flow rate of about 0.01 mL/hr to 1 mL/hr.
After the described steps, the nano lines 17 can be left at room temperature under the regular atmosphere, such that the metal compound is slowly chemically reduced by the chemically reducing agent in the metal precursor wires 17 A. As a result, nano metal wires 21 are obtained. In one embodiment, the nano lines 17 can be annealed under the atmosphere to accelerate chemical reduction. For example, the anneal step can be performed at a temperature of about 100° C. to 200° C. A suitable solvent can be adopted to wash out the polymer tube 17 B surrounding around the nano metal wire 21 . For example, when the polymer tube 17 B is PVP, it can be washed out by water, and the nano metal wires 21 in FIG. 4 are left. When the polymer tube 17 B is PAN, it can be washed out by THF. The nano metal wire 21 prepared by the described steps has a diameter of 50 nm to 500 nm, an aspect ratio of greater than 1000, and a conductivity of about 10 4 S/m to 10 7 S/m. Note that the nano metal wire 21 has an unlimited maximum length. In other words, the nano metal wire has an unlimited maximum aspect ratio. In one embodiment, the nano metal wire 21 may have a centimeter-scaled length, e.g. at least 1 cm or even at least 10 cm. The nano metal wire 21 can be applied to an anti-EMI paint, an RFID device, a solar cell conductive paste, a long-lasting and anti-bacterial peelable spray, and a transparent conductive film, and the likes.
Below, exemplary embodiments will be described in detail with reference to the accompanying drawings so as to be easily realized by a person having ordinary knowledge in the art. The inventive concept may be embodied in various forms without being limited to the exemplary embodiments set forth herein. Descriptions of well-known parts are omitted for clarity, and like reference numerals refer to like elements throughout.
EXAMPLES
In following examples, the needle had a shell pipe with a diameter of 1.25 mm and a core pipe with a diameter of 0.95 mm. The needle and the parallel electrode collector plate had a distance of 13 cm therebetween. The voltage applied to the needle was 10 kV. One electrode plate of the parallel electrode collector plate was electrically connected to ground, and another electrode plate was electrically connected to a voltage of 1 kV. Diameters of the nano lines and the nano metal wires were all measured by transmission electron microscopy (TEM, JEOL JEM-2100F).
Example 1
An ethylene glycol solution of silver nitrate (30 mg/mL) was put into a syringe connected to a core pipe of a needle. A methanol solution of PVP (200 mg/mL) was put into another syringe connected to a shell pipe of the needle. The silver precursor solution in the core pipe was controlled by a syringe pump to have a flow rate of 0.1 mL/hr, and the polymer solution in the shell pipe was controlled by another syringe pump to have a flow rate of 1 mL/hr. A nano line having a diameter of about 2.2 μm was electrostatically spun.
The nano line was annealed at 150° C. under the atmosphere for about 8 minutes, and then washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 500 nm, a length of about 10 cm, and an aspect ratio of 200000 was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 5 .
Example 2
Similar to Example 1, the difference in Example 2 was the annealing period being changed to about 20 minutes. After annealing, the nano line was washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 500 nm, a length of about 10 cm, and an aspect ratio of 200000 was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 5 .
Example 3
Similar to Example 1, the difference in Example 3 was the annealing period being changed to about 10 hours. After annealing, the nano line was washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 500 nm, a length of about 10 cm, and an aspect ratio of 200000 was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 5 .
Comparative Example 1
Similar to Example 1, the difference in Comparative Example 1 was the nano line having a diameter of 2.2 μm being directly washed by water to remove the polymer tube (without any annealing). The silver precursor wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 5 .
TABLE 1
Annealing
Nano silver
Nano silver
period at
wire
Nano silver
wire aspect
150° C.
diameter
wire length
ratio
Example 1
8 minutes
~500 nm
10 cm
2 × 10 5
Example 2
20 minutes
~500 nm
10 cm
2 × 10 5
Example 3
10 hours
~500 nm
10 cm
2 × 10 5
Comparative
Without
none
none
none
Example 1
annealing
As shown in FIG. 5 and Table 1, the absorption peaks at about 420 nm of the nano silver wires were higher and red-shifted as the length of the annealing periods were increased. Accordingly, the annealing step was beneficial for chemically reducing the silver nitrate to silver.
Example 4
An ammonium hydroxide solution of silver oxide (with a silver oxide concentration of 5 mg/mL and an ammonium hydroxide concentration of 33%) was put into a syringe connected to a core pipe of a needle. A methanol solution of PVP (200 mg/mL) was put into another syringe connected to a shell pipe of the needle. The silver precursor solution in the core pipe was controlled by a syringe pump to have a flow rate of 0.01 mL/hr, and the polymer solution in the shell pipe was controlled by another syringe pump to have a flow rate of 1 mL/hr. A nano line having a diameter of about 1 μm was electrostatically spun. The nano line was left to stand at room temperature under the atmosphere for 4 hours, and then washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 300 nm and a length of 10 cm was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 6 .
Example 5
Similar to Example 4, the difference in Example 5 was the nano line being left to stand at room temperature under the atmosphere for 4 days. Thereafter, the nano line was washed by water to remove the polymer tube. As such, the nano silver wire with a diameter of about 300 nm and a length of 10 cm was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 6 .
Example 6
Similar to Example 4, the difference in Example 6 was the nano line having a diameter of about 1 μm being annealed at 200° C. under the atmosphere for 10 minutes. Thereafter, the nano line was washed by water to remove the polymer tube. As such, the nano silver wire with a diameter of about 300 nm and a length of 10 cm was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 6 .
Example 7
Similar to Example 6, the difference in Example 7 was the nano line being annealed at 200° C. for 20 minutes. Thereafter, the nano line was washed by water to remove the polymer tube. As such, the nano silver wire with a diameter of about 300 nm and a length of 10 cm was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 6 .
Example 8
Similar to Example 6, the difference in Example 8 was the nano line being annealed at 200° C. for 30 minutes. Thereafter, the nano line was washed by water to remove the polymer tube. As such, the nano silver wire with a diameter of about 300 nm and a length of 10 cm was obtained. The nano silver wire was measured by a spectrometer to obtain its absorption spectrum as shown in FIG. 6 .
TABLE 2
Nano
Nano
silver
silver
Nano silver
Anneal
wire
wire
wire aspect
temperature/period
diameter
length
ratio
Example 4
Room temperature/
~300 nm
10 cm
3.3 × 10 5
4 hours
Example 5
Room temperature/
~300 nm
10 cm
3.3 × 10 5
4 days
Example 6
200° C./10 minutes
~300 nm
10 cm
3.3 × 10 5
Example 7
200° C./20 minutes
~300 nm
10 cm
3.3 × 10 5
Example 8
200° C./30 minutes
~300 nm
10 cm
3.3 × 10 5
As shown in FIG. 6 and Table 2, the nano silver wires were formed by only being left to stand at room temperature for a long period without annealing. However, the anneal step may accelerate the forming of the nano silver wires. The nano silver wire having a diameter of 300 nm and a length of 10 cm was formed by annealing at a temperature of 200° C. for a period of 10 minutes (longer annealing period was not needed). The nano silver wire had a conductivity of 6.9×10 4 S/m.
Example 9
An ammonium hydroxide solution of silver oxide (with a silver oxide concentration of 1 mg/mL and an ammonium hydroxide concentration of 33%) was put into a syringe connected to a core pipe of a needle. A methanol solution of PVP and TBAP (with a PVP concentration of 100 mg/mL and a TBAP concentration of 10 mg/mL) was put into another syringe connected to a shell pipe of the needle. The silver precursor solution in the core pipe was controlled by a syringe pump to have a flow rate of 0.01 mL/hr, and the polymer solution in the shell pipe was controlled by another syringe pump to have a flow rate of 1 mL/hr. A nano line having a diameter of about 0.6 μm and a length of 10 cm was electrostatically spun. The nano line was annealed at 200° C. under the atmosphere for 20 minutes, and then washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 357 nm was obtained.
Example 10
An ammonium hydroxide solution of silver oxide (with a silver oxide concentration of 5 mg/mL and an ammonium hydroxide concentration of 33%) was put into a syringe connected to a core pipe of a needle. A methanol solution of PVP and TBAP (with a PVP concentration of 100 mg/mL and a TBAP concentration of 10 mg/mL) was put into another syringe connected to a shell pipe of the needle. The silver precursor solution in the core pipe was controlled by a syringe pump to have a flow rate of 0.01 mL/hr, and the polymer solution in the shell pipe was controlled by another syringe pump to have a flow rate of 1 mL/hr. A nano line having a diameter of about 0.7 μm and a length of 10 cm was electrostatically spun. The nano line was annealed at 200° C. under the atmosphere for 20 minutes, and then washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 464 nm was obtained. As known by comparison with Example 9, a nano silver wire having a larger diameter can be obtained through a higher silver oxide concentration.
Example 11
An ammonium hydroxide solution of silver oxide (with a silver oxide concentration of 1 mg/mL and an ammonium hydroxide concentration of 33%) was put into a syringe connected to a core pipe of a needle. A methanol solution of PVP and TBAP (with a PVP concentration of 100 mg/mL and a TBAP concentration of 30 mg/mL) was put into another syringe connected to a shell pipe of the needle. The silver precursor solution in the core pipe was controlled by a syringe pump to have a flow rate of 0.01 mL/hr, and the polymer solution in the shell pipe was controlled by another syringe pump to have a flow rate of 1 mL/hr. A nano line having a diameter of about 0.4 μm and a length of 10 cm was electrostatically spun. The nano line was annealed at 200° C. under the atmosphere for 20 minutes, and then washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 285 nm was obtained. As known by comparison with Example 9, a nano silver wire having a smaller diameter can be obtained through a higher TBAP concentration.
The nano silver wire in Example 11 had a resistivity of 4.3×10 −4 Ω·cm. A bulk silver had a resistivity of 1.6×10 −6 Ω·cm (See Applied Physics Letters 95, 103112, 2009). A single crystalline nano silver wire had a resistivity of 2.19×10 −4 Ω·cm (See Applied Physics Letters 95, 103112, 2009). A poly crystalline nano silver wire had a resistivity of 8.29×10 −4 Ω·cm (See Nano letter, Vol. 2, No. 2, 2002). Accordingly, the nano silver wire prepared in Example 11 of the disclosure should be a single crystalline nano silver wire. An XRD spectrum of the nano silver wire is shown in FIG. 7 . The nano silver wire had a single crystalline face-centered cubic structure, as determined by TEM and XRD. Also, the nano silver wire had high uniformity and a high conductivity.
Example 12
An ammonium hydroxide solution of silver oxide (with a silver oxide concentration of 5 mg/mL and an ammonium hydroxide concentration of 33%) was put into a syringe connected to a core pipe of a needle. A methanol solution of PVP and TBAP (with a PVP concentration of 100 mg/mL and a TBAP concentration of 30 mg/mL) was put into another syringe connected to a shell pipe of the needle. The silver precursor solution in the core pipe was controlled by a syringe pump to have a flow rate of 0.01 mL/hr, and the polymer solution in the shell pipe was controlled by another syringe pump to have a flow rate of 1 mL/hr. A nano line having a diameter of about 0.6 μm and a length of 10 cm was electrostatically spun. The nano line was annealed at 200° C. under the atmosphere for 20 minutes, and then washed by water to remove the polymer tube. As such, a nano silver wire with a diameter of about 375 nm was obtained. As known by comparison with Example 11, a nano silver wire having a larger diameter can be obtained through a higher silver oxide concentration. As known by comparison with Example 10, a nano silver wire having a smaller diameter can be obtained through a higher TBAP concentration.
TABLE 3
Nano
Nano
Nano
silver
Silver oxide
TBAP
silver
silver
wire
con-
con-
wire
wire
aspect
centration
centration
diameter
length
ratio
Example 9
1 mg/mL
10 mg/mL
~357 nm
10 cm
2.8 × 10 5
Example 10
5 mg/mL
10 mg/mL
~464 nm
10 cm
2.2 × 10 5
Example 11
1 mg/mL
30 mg/mL
~285 nm
10 cm
3.5 × 10 5
Example 12
5 mg/mL
30 mg/mL
~375 nm
10 cm
2.7 × 10 5
It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed methods and materials. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalents. | Disclosed is a method of manufacturing a nano metal wire, including: putting a metal precursor solution in a core pipe of a needle; putting a polymer solution in a shell pipe of the needle, wherein the shell pipe surrounds the core pipe; applying a voltage to the needle while simultaneously jetting the metal precursor solution and the polymer solution to form a nano line on a collector, wherein the nano line includes a metal precursor wire surrounded by a polymer tube; chemically reducing the metal precursor wire of the nano line to form a nano line of metal wire surrounded by the polymer tube; and washing out the polymer tube by a solvent. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to dysfunctional energy metabolism of both glucose and lipids in animals and humans. More particularly, a novel combination of metabolic cofactors, L-carnitine combined with acetyl-L-carnitine, restores normal mental and physical activity to aged patients with dysfunctional energy metabolism and, when employed prophylactically, prevents development of related syndromes.
In the normal course of aging an organism's ability to synthesize, conserve, and absorb crucial metabolic cofactors declines. Conversion of nutrients to useful energy within cells involves highly specific enzymatic processes which are sensitive to presence or absence of these cofactors. In the higher order of animals, especially with respect to humans, as well as laboratory rodents, enzyme pathways of energy metabolism are known with relative precision. Despite extensive research efforts, however, interrelationship of many metabolic processes and enzymatic cofactors remain imprecisely known. Indeed, metabolic interrelationships of enzymatic cofactors L-carnitine and acetyl-L-carnitine in cardiac and skeletal muscle have not been completely defined. The same is true in nervous tissue, especially the brain, where available research data concerning function of these cofactors are often contradictory and inconclusive owing to the inordinate difficulty in establishing truly controlled experimental formats. Much of what is known has been gained from the organ's response to traumatic, toxic, and ischemic insults as well as investigations of these cofactors' effects in chronically diseased brains. Such information provides little or no guidance to those concerned with psychophysiologic and psychomotor disturbances or confronting syndromes affecting multiple tissues. The following brief notations are believed to illustrate the complexity of the state of the art knowledge of diseases of energy metabolism.
The study of disease of energy metabolism commonly referred to as mitochondrial diseases is an emerging specialty in human medicine. Most of these diseases arise from mutation of the mitochondrial genomes and, to a lesser extent, nuclear genes. Such mutations result in specific dysfunctional enzymes in metabolic pathways and in structural changes of mitochondria which disrupt enzyme orientation in metabolic pathways thereby impairing their efficiency. Mitochondrial genome mutations may exist at birth but typically occur over time as base dilutions, substitutions, and insertions during the course of replication; or in response to environmental factors, disease, and accumulation of toxic metabolites. Clinical syndromes presented depend upon the metabolic pathway affected and the proportion of dysfunctional mitochondria that has been attained. Organs normally effected by disease of energy metabolism are highly differentiated, nonregenerating tissues requiring high levels of oxygen and energy, such as brain and skeletal and heart muscle. Treatment of these diseases is directed to sustaining life by supplementing high levels of metabolic cofactors in an effort to skew metabolism along specific pathways and to providing substrates for the pathways. Rarely, in human medicine, do deficiencies of cofactors or substrates cause diseases of energy metabolism. In veterinary medicine only a few genetically based diseases of energy metabolism are recognized. Among them are dilated cardiomyopathy in dogs and stress syndrome in swine. However, deficiencies of metabolic cofactors in dogs have been investigated. A study of commonly encountered age-related syndromes in old dogs, examples of which are included in this application, revealed them to be due to dysfunctional energy metabolism. More specially, syndromes involving heart and skeletal muscle were relieved by L-carnitine supplemention while a syndrome affecting the brain was relieved by increased acetyl-L-carnitine intake. However, complex interrelationships exist. For example, a treatment for a psychotic syndrome with acetyl-L-carnitine was successful but resulted in emergence of a heart failure syndrome and both cofactors were required to normalize the dog. In another case, synergistic effects were realized with the two cofactors combined as opposed to their individual use in treating a syndrome involving skeletal muscle. And, in yet another case, a dog that heretofore had required heavy sedation to control an epileptic syndrome, experienced unexpected improvement in after it had been treated with combined L-carnitine and acetyl-L-carnitine for several weeks.
L-carnitine as well as acetyl-L-carnitine are natural constituents of higher organisms, particularly animal heart and muscle tissue and can be synthesized by the body or obtained from red meat, poultry, fish, and dietary products. L-carnitine is absorbed from the small intestine into systemic circulation at a rate of about 2 to 5 mg per pound body weight which is compatible with normal physiologic function and the basis for dosages in the accompanying studies. In standard medical treatment of syndromes related to deficiency of L-carnitine or L-carnitine-dependent enzymes dosage of L-carnitine employed may be 10 to 50 times higher than rate of physiologic intestinal absorption. This affords passive diffusion of carnitine into systemic circulation but such high dosages have the risk of causing diarrhea.
L-carnitine (3-hypodroxy-4-N-trimethylaminobutyric acid) has two main functions, both critical to energy metabolism. The first is translocation of long-chain fatty acids from the cytosol across the outer and inner mitochondrial membranes and intervening space into the mitochondrial matrix. The second function is to modulate intracellular CoA homeostasis within the mitochondrial matrix by transesterifation of acyl-CoA esters produced in B-oxidation which regenerates CoA and acylcarnitine. Accumulation of long chain acyl-CoA esters is a consequence of enzyme disfunction and metabolic impairment or stasis in the B-oxidation system. Resulting shortage of available CoA then limits transfer of acetyl groups to the Krebs cycle for energy production. Acylcarnitine, produced during homeostasis, can be exchanged across the mitochondrial membrane for free carnitine and eventually transported out of the cell to be excreted in urine. Canids are unique in the fact that their liver and kidneys synthesize carnitine but they lack an enzyme in skeletal and cardiac muscle which is crucial to the last stage of L-carnitine synthesis. In dogs L-carnitine is synthesized in the liver and transported to muscle tissue.
Acetyl-L-carnitine (-trimethyl-B-acetylbutyrobetaine) shares intracellular CoA homeostatic function with carnitine. It is the prevalent ester of carnitine in tissue, freely exchangeable across subcellular membranes, and can serve as a pool of acetyl groups to regenerate acetyl-CoA. This property comes into play in instances of excessive exercise where glycolysis has resulted in accumulation of lactic acid in muscle cells. Studies with rat brain tissue show acetyl-L-carnitine to be associated with increased glycolysis and oxygen metabolism. Other studies indicate acetyl-L-carnitine enhances ketone-body metabolism in rat brains. In experimentation with rats acetyl-L-carnitine has been shown to maximize energy production, promote membrane stability, restore membrane changes that are age-related, and serve as precursor to acetylcholine. Cholinergic effects enhance nerve impulse transmission and have been demonstrated to counter or delay age-changes and dementia in brains of rodents and humans.
In addition to depleted available energy and concomitant depression of cell and organ function another consequence of impaired energy metabolism is formation of free oxygen radicals and their destructive effects on proteins and other large molecules, mitochondrial membranes, and especially mitochondrial DNA. Environmental sources of free radicals are infection, drugs, hypoxia, chemicals, and food. These destructive effects are cumulative leading to development of physiologic dysfunctions with increasing age, and along with mitochondrial genome mutation from other causes, must be considered as contributors to the etiology of syndromes seen with the dogs in this report. Normally, cell and organ function deteriorates with age resulting in reduced biosynthesis of metabolites and cofactors, reduced digestive function and enteral absorption, and impaired renal tubule resorption from glomerular filtrate. In elderly dogs any or all of the above can lead to depletion of tissue reserves of L-carnitine and acetyl-L-carnitine to the extent that energy metabolism is impaired.
Four syndromes, psychosis, skeletal muscle weakness and atrophy, epileptiform convulsions, and cardiomyopathy were observed in dogs in this study. Syndromes presented as singular entities as in the skeletal muscle syndrome or as complex of syndromes. Psychosis, in the form of extreme anxiety with trembling, hiding and panicky flight are common in old dogs exposed to sharp noises such as fireworks discharges. Even a mild stimulant such as the sound of cellophane being crumbed into a ball will illicit a panic response in some dogs. Management of most such cases is with tranquilizers during periods when stimuli are most prevalent (e.g. New Years Eve and The Fourth of July). Tranquilizers do nothing to cure the patient, their effect is psychological depression. When patients become extremely debilitated by the psychosis mood altering drugs such as doxepin and fluoxetine can be employed. Here again a cure will not be forth coming. At best the animal will be so heavily sedated as to not pose a threat to itself, property, or the public. Pharmacologically-active mind-depressions do not correct any metabolic imbalances in the brain, hence do not effect a cure. In some cases psychotic episodes progress to grand mal seizures. Depressant drugs are the common means employed for their control. Phenobarbital, primidone, and/or KBr are consumed once to several times a day. The drugs do not correct the underlying metabolic dysfunction in the brain but they do stop the seizures at the expense of greatly depressing the patient. Psychotic and seizuring dogs are not demented in the sense that there is large-seal neuronal dysfunction with loss of inelegance, memory, or awareness of surroundings. Psychoses are almost the opposite, with heightened awareness of sounds and events in the environment. They may precipitate seizures.
Among the causes of skeletal muscle weakness and reduction of mass are nutritional deficiency, in particular deficiency of SE and vitamin E. In cases of nutritional myopathy, refined to as white muscle disease, the vitamin E interrelates metabolically with SE and can be a valuable adjust to therapy. This condition is common to herbivorous and omnivorous but not carnivorous. A myopathy common in dogs is denervation myopathy, a condition that develops secondary to herniation of intervertebral dises and ankylosing spondyloarthropathy. Where spinal nerves are damaged reduced impulse stimulation to the innervated muscle leads to weakness, degeneration, and atrophy. This form of muscle disease is managed by attempting to reduce trauma to the spinal nerve by controlling chronic inflammation and bone formation along the nerve's course from the spine with drugs classified as non-steroidal anti-inflammatory agents. If skeletal muscle is not exercised it will become weak and degenerate and eventually atrophy. This condition, common to traumatic injuries, precludes normal function after extended periods of time. There are auto-immune myopathies where the body produces an immune reaction, usually to some infectious agent, that cross reacts with skeletal muscle. Management of these conditions is based upon suppression of the immune reaction for an undetermined period of time. Eventually, the reaction subsides and the immune depressant drugs can be with drawn. There are other causes of skeletal muscle weakness and atrophy. Clinically they are morphologically similar to one and other and require biopsy for definitive diagnosis.
Heart failure secondary to dilated cardiomyopathy has been treated with high dosages of L-carnitine, 100 mg per pound body weight. Such massive therapy is only moderately successful, at best. In most cases prognosis is very guarded. One reason for the poor response may be that diagnosis is not forthcoming until pathology is so advanced it cannot be reversed. Another consideration is that L-carnitine therapy only addresses lipid metabolism in the heart ignoring the part glycolysis may contribute. Cardiac arrhythmias are part of heart failure and evidence of pathology of heart muscle. Arrhythmias are treated with pharmachologically active drugs which may stabilize the heart. Drugs such as lidocaine, propanalol, digoxin, and procainamide all are useful in stabilizing the heart beat which may be critical at times but such drugs do not address the metabolic disturbance that caused the pathology. It is common for dogs with cardiac arrhythmias to die suddenly or, at best, be forced to remain on medication for extended periods, even for life.
As a consequence of above-noted complexities in identifying and treating syndromes related to dysfunctional energy metabolism as well as understanding their interrelationships little progress has been achieved in prevention and therapy. The following examples of U.S. Patents relating to carnitine and acetyl-L-carnitine are illustrative of the existing state of the art.
U.S. Pat. No. 4,346,107 relates specifically to the use of acylcarnitine in treating dementia of human patients particularly when mental dysfunction is related to impaired cerebral blood flow. Typifying numerous approaches to management of dementias, is does not investigate psychoses and epileptiform seizures as being associated with deficits of energy metabolism, their connection with deficiencies of L-carnitine and acetyl-1-carnitine, the possibility of precipitating other energy deficit syndromes as a consequence of therapy with a single metabolic cofactor, and the need for therapy that modulates both glycolyses and lipid metabolism.
U.S. Pat. No. 4,599,232 relates to combination of carnitine or acetylcarnitine and coenzye Q10 for tissue metabolic disorders involving circulatory function. The patent's use of coenzymes Q10 directs its effects towards control of free radical excess and facilitation of oxidative phosphorylation, the final stage of energy metabolism. It does not address the observed synergistic effects of combined L-carnitine and acetyl-L-carnitine on glycolysis and lipid metabolism nor does it recognize the need of both metabolic cofactors when treating dysfunctional energy metabolism related to deficit of L-carnitine or acetyl-L-carnitine as discovered in the present patent.
U.S. Pat. No. 5,576,384 relates to the general use of acylcarnitine for therapy of patients with Acylcarnitine Metabolic Dysfunction Syndrome. It excludes consideration of carnitine metabolism disorders and the combined therapy for disorders where both deficiencies may exist.
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BRIEF SUMMARY OF THE INVENTION
The present invention, A novel combination of L-carnitine and acetyl-L-carnitine, has been discovered to relieve syndromes related to mutations of mitochondrial genomes and age-related impairment of energy metabolism due deficiencies of L-carnitine and acetyl-L-carnitine in domesticated animals.
The invention in its various forms are easy to prepare. Liquids for oral use are prepared at room temperature by dissolving prescribed quantities of crystalline forms of the cofactors in water, adding preservative and coloring and/or flavoring, filter sterilizing, and bottling. Liquid for injection is prepared at room temperature by dissolving prescribed amounts of each cofactor in water. If the material is to be dispensed in a multi-dose vial, preservative is added before the pH is adjusted with NaOH to neutrality and the solution is filter sterilized and bottled. Dry forms of the invention are prepared by mixing prescribed amounts of the two desiccated cofactors. If the invention is to be encapsulated, an anticaking agent to facilitate production may be added prior to encapsulation. If the dry preparation is to be dissolved for intravenous injection the desecrated powder or crystalline mixture is measured into glass vials, sealed and sterilized.
Specific quantities of L-carnitine and acetyl-L-carnitine provided in the aqueous solutions of the invention may be varied depending upon projected use. As an example, it is within the comprehension of the invention that solutions may be prepared to allow each milliliter thereof to contain: from about 0.1 to 400 milligrams L-carnitine and 0.1 to 400 milligrams acetyl-L-carnitine. Similarly, ratios of carnitine to Alcar in powdered forms can be varied from 1 to 100 depending upon intended usages.
All preparations of the invention are easy, safe and convenient to use. The liquid for oral consumption can be taken directly into the mouth and swallowed or measured into it with a spoon, dropper, syringe, or like device. Similarly, the liquid preparation can be measured into food or drink for consumption. The usual, standardized techniques for parenteral injection of drug with hypodermic needle and syringe is to be employed for administering the injectable format of the invention subcutaneously, intramuscularly, intravenously, or as an additive to compatible liquid medicaments designed for intravenous injection.
Among the preferred forms of the invention is a solution formulated to contain 45mg L-carnitine and 45 mg acetyl-L-carnitine per milliliter. Such a preferred solution is particularly useful for oral administration at a dosage level to provide from about 2 to 4 milligrams of each cofactor per pound of body weight. The invention is beneficial in aleaveating symptoms when added to the food of psychotic domesticated animals, those with cardiomyopathy or skeletal muscle weakness or atrophy, those with tendency to have epileptiform seizures or in aged obese or debilitated animals when these conditions are due to inadequacy of available L-carnitine and/or acetyl-L-carnitine. This preferred form of the invention is particularly useful for supplementing the diet at a rate of about 5 milligram per pound of body weight on a daily basis to prevent development of such as cardiomyopathy, skeletal muscle weakness or atrophy, psychosis, some forms of epilepsy, and to generally improve mental and physical activity and well-being.
The purpose of the invention is to treat or prevent from developing disease syndromes related to inadequate tissue levels of L-carnitine and/or acetyl-L-carnitine and to treat or prevent disease syndromes related to mutations of mitochondrial DNA, changes in mitochondrial structure, and deterioration of the body's ability to synthesize, conserve, and absorb L-carnitine and acetyl-L-carnitine. One severely psychotic dog had been unsuccessfully treated for about one year with two different mood-altering drugs commonly used for treatment of such mental derangements. The owner, committed to euthanasia, agreed to a final effort to save the animal; the novel and untested use of acetyl-L-carnitine to treat psychosis. Response was prompt, recovery began in two days. The effects of acetyl-carnitine on brain function appeared to correct the dog's psychosis. But when the dog became normal mentally, acute circulatory failure developed. L-carnitine was substituted for acetyl-L-carnitine and the circulatory failure was resolved. Shortly, however, the psychosis resumed. L-carnitine and acetyl-L-carnitine were not metabolically interchangeable in this case. A novel, treatment was initiated. L-carnitine and acetyl-L-carnitine were combined and administered in the dog's food, 5 mg per pound body weight. He promptly became normal and remained, so receiving daily supplementation with the invention. This case demonstrated that, with diseases of energy metabolism, some syndromes may be subclinical only to be expressed in time or when a more prominent syndrome is relieved, increased activity may bring an underlying syndrome to light. Or, when treating a syndrome with one cofactor, in this case acetyl-L-carnitine, a disturbance in metabolism may develop in another organ necessitating the other cofactor, L-carnitine. It is clear that when treating diseases of energy metabolism in old dogs combined L-carnitine and acetyl-L-carnitine are in order.
This principle was underscored by a dog treated with L-carnitine for skeletal muscle atrophy, weakness and pain. It responded, functioning normally in three weeks. Then acetyl-L-carnitine was substituted for L-carnitine to observe any cross-effectiveness. No cross-effect was observed. Shortly, symptoms of muscle weakness and pain resumed. The cofactors were mixed, as in the powdered preparation of the invention, and added to the dog's food, 5 mg per pound body weight. Within one week she was normal. This accelerated response compared with the time of response when treatment was with L-carnitine alone would suggest metabolic synergism exists between L-carnitine and acetyl-L-carnitine.
A third case demonstrated effectiveness of combined L-carnitine and acetyl-1-carnitine for treating skeletal muscle weakness and neurologic symptoms. Both syndromes had been long standing in an old dog that was presented with acute circulatory failure. The dog's heart disease was diagnosed as being early cardiomyopathy without marked enlargement. When treated with procainamide and the invention at a rate of 5 mg of combined 1-carnitine and acetyl-L-carnitine per pound of body weight the initial arrhythmia was converted over night. After one week the procainamide therapy was stopped the heart continued to improve as the dog received the invention on a daily basis and within a month the electrocardiogram was normal. This was an unprecedented response, for most such cases die within a few days. It is assumed the invention was instrumental in correcting the metabolic imbalance causing the cardiomyopathy.
L-carnitine and acetyl-L-carnitine are biochemically interchangeable in mitochondria through action of the enzyme carnitine acetyl-transferase. However, evidence in the studies reported herein indicate distinct differences in metabolic function of the two cofactors with no apparent cross reaction or substitution between them. It is well accepted that L-carnitine effects are primarily on energy metabolism of lipids. However, metabolic pathways involving acetyl-L-carnitine are not well defined. The following may explain how the psychotic dog was benefitted: Research indicates acetyl-L-carnitine enhances glycolysis, oxygen metabolism and energy production in the brain. Which may partially explain beneficial effects observed. Studies of humans with a mitochondrial disease, MELAS, suggest symptoms and lesions are the result of lactic acid accumulation in the brain with concomitant brain edema. Stressful events lead to increase demand for energy in the brain but with limited reserves of acetyl-L-carnitine glycolysis is impeded and lactic acid accumulates. To measurably increase glycolysis, acetyl-L-carnitine facilitate metabolism of pyruvate, making more energy available for cell function and limiting accumulation of lactic acid with its detrimental effects. This same mechanism, acetyl-L-carnitine facilitated pyruvate metabolism, explains the synergism elicited by L-carnitine and acetyl-L-carnitine, the invention was used to treat dogs with skeletal muscle weakness and pathology. Treatment of cardiomyopathy with the invention at physiological levels, mg per pound body weight, more successful than when L-carnitine alone is given even at dosages 20 times higher. Although L-carnitine dependant lipid metabolism is the major energy source in muscle, acetyl-L-carnitine dependant glycolysis is essential to normal muscle cell function.
The invention was superior to conventional therapy for treating the following syndromes that arose from disturbances of energy metabolism:
Psychotic behavior was eliminated and the affected dog regained demeanor and activity level similar to three years previously while its diet was supplemented daily with mg of the invention per pound body weight. It showed no evidence of depression or sedation associated with conventional therapy.
Similarly, a dog with long standing epileptiform seizures, controlled by heavy dosages of KBr had only one mild seizure a month during diet supplementing with the invention at mg per pound of body weight daily. Without KBr therapy.
Two dogs with profound skeletal muscle weakness became fully active while receiving diet supplemention with mg of the invention per pound of body weight each day. One dog regained the ability to jump into a pickup truck. This patient had a previously-undescribed myopathy diagnosed from a biopsy as a degenerative condition probably related to dysfunctional energy metabolism. Other more traditional therapies for treating the myopathy were ineffective. The other dog was able to run freely and chase cats, previous to treatment it had to be supported with a sling under its belly when walking more than a few feet.
Two dogs with circulatory failure recovered completely during the course of daily diet supplementation with mg of the invention per pound of body weight. The dogs had a brief course of oral treatment with procianamide. The superiority of invention was manifested in the completeness of recovery without prolonged anti-arrhythmia therapy.
Other aspects and advantages of the present invention will be apparent upon consideration of the following detailed description thereof.
DETAILED DESCRIPTION OF THE INVENTION
The term "cofactor" in general refers to carnitine, Alcar, other vitamins, and trace minerals that facilitate chemical reactions with specific enzymes in cells. "Parenteral" shall mean any administrative mode other than oral and shall include subcutaneous, intramuscular and intravenous injection. "Syndrome" is a set of symptoms, or complex of symptoms occurring together which may or may not characterize a specific disease entity. "Carnitine and Alcar responsive syndrome" shall represent a symptom complex which is benefited by amelioration of symptoms toward the normal through treatment of the patient with carnitine and acetyl-L-carnitine.
The purpose of the invention is to treat, or prevent from developing, disease syndromes related to inadequate tissue levels of one or both metabolic cofactors, and to treat or prevent disease syndromes related inadequate intake of L-carnitine or acetyl-L-carnitine, or to mutations of mitochondrial DNA, changes in mitochondrial structure, and deterioration of the body's ability to synthesize, conserve and absorb L-carnitine and acetyl-L-carnitine.
EXAMPLE 1
This example relates to the preparation of one liter of a stable acqueous solution containing, per milliliter, 45 mg L-carnitine and 45 mg acetyl-L-carnitine. All procedures are carried out at room temperature unless otherwise indicated.
A solution is prepared by dissolving 45 grams of 1-carnitine in 500 ml water. To this solution 45 grams of acetyl-1-carnitine are added and dissolved.
A second solution is made by dissolving 1 gram of methyl paraben in 400 milliliters water. Dissolution can be hastened by warming the water to 40 degrees centigrade and stirring constantly. The solutions are cooled to room temperature and water is added sufficient to bring the final quantity to 1000 milliliters. The final solution is filtered to remover any and all bacteria, and like-sized microbes. This sterile solution is dispensed in sterile bottles.
This solution has a mildly acidic taste that enhances many food flavors it is intended for oral administration or to be added to the diet or drinking water of an individual animal at the rate of one milliliter per fifteen pounds body weight.
EXAMPLE 2
This example relates to preparation of one liter of sterile, neutral, stable aqueous solution containing, per milliliter, 16.7 mg carnitine and 16.7 mg acetyl-L-carnitine. All procedures are carried out at room temperature.
A solution is prepared by dissolving 16.7 grams of L-carnitine in 400 milliliters of distilled, pyrogen free water. When it is dissolved 16.7 grams acetyl-L-carnitine is added to the solution and is dissolved.
A second solution is made by dissolving 1 gram of methyl paraben in 400 milliliters water. Dissolution can be hastened by warming the water to 40 degrees centigrade and stirring constantly. The second solution is mixed with the first solution.
The pH of the mixed solutions is adjusted to neutrality with approximately 2.95 grams NaOH. Sufficient quantity water is added to bring the final volume to 1000 milliliters and the solution is filtered through sterile equipment to remove bacteria and like-sized microbes. It is then bottled in sterile rubber-stopped glass vials.
This solution is intended for subcutaneous, intramuscular or intravenous injection at the rate of 1 ml per 15 pounds body weight. To provide the added quality of being useful in animals unable to consume or retain injested materials and in instances where rapidity of response to therapy may be critical for the life or well being of the patient.
EXAMPLE 3
This example relates to preparation of desiccated powder containing equal amounts of the L-carnitine and acetyl-L-carnitine.
The mixture is prepared by combining and uniformly mixing 50 mg of both desiccated L-carnitine and acetyl-L-carnitine in a low moisture atmosphere. An anticking agent may be blended into the mixture to facilitate processing through a capsule filling machine. The choice of anticaking agent must be compatible with state and federal pure food and drug regulations. The powdered preparation is placed in gelatin capsules of a size sufficient to contain 45 mg L-carnitine and 45 mg acetyl-L-carnitine to be swallowed by a 15 pound dog or the capsule may be opened and the contents sprinkled onto or mixed with the patient's food.
EXAMPLE 4
This example relates to preparation of sterile desiccated powder containing equal amounts L-carnitine and acetyl-L-carnitine. The mixture is prepared by combining and uniformly mixing, in a dry atmosphere, 50 grams amounts of desiccated L-carnitine and acetyl-L-carnitine. The mixture is measured in 200 mg amounts into sterile, dry glass ampules which are then sealed. Powder in vials is to be dissolved with sterile water for intravenous use in cases of acute circulatory failure related to L-carnitine and acetyl-L-carnitine responsive cardiopathy or mitochondrial genome mutations where energy metabolism is compromised.
Consistent with the above, oral administration of preparations defined in Examples 1 and 3 were found to be useful in treating pet dogs with cardiomyopathy, skeletal muscle weakness, psychosis and epilepsy. Where these syndromes were actively manifested the preparation eliminated or markedly ameliorated symptoms. When the preparations were discontinued or reduced in amount consumed syndromes recurred. Continued supplementation prevented syndrome development. The following examples relate to the effectiveness of the preparations of the invention.
EXAMPLE 5
A twelve year old male Weimaraner was treated for almost one year for anxiety and trembling. It all began when a minor earthquake one week previous to initial admittance to the hospital resulted in a fearful change in the dog's behavior. Normally placid, following the quake he had trembled uncontrollably when put in his owner's backyard. He was reluctant to enter the hospital and tried to avoid being handled. However, he was not aggressive nor did he show any tendency to bite from fear. Cranial nerve function was normal and clinical examination revealed no physical ailments. It was assumed the dog had a form of anxiety and he was treated with 25 mg of the mood-altering antipsychosis drug doxepin HCl orally once daily. This satisfactorily diminished symptoms for several weeks after which anxiety gradually returned. Six months after starting treatment he was as troubled as when first presented. Medication was changed to 20 mg of another antipsychosis drug fluoxetine HCl orally once daily. Again, anxiety subsided for a few weeks but in time returned and steadily increased in severity. In spite of daily behavior-modifying therapy his mental condition deteriorated to the extent that he voluntarily confined himself and hid behind a couch in one room of the house. Trembling had become violent when he was taken out of doors and he was unable to go on short walks. His food bowl frightened him and he refused to eat unless fed from the owner's hand.
When again brought to the hospital after almost eleven months of therapy with antipsychosis drugs he was very psychotic. His owner had to drag the panicking dog into the waiting room where he trembled and coward under the owner's chair. Clinical examination was much as it was initially. Euthanasia was considered but the owners opted for increasing fluoxetine HCI dosage to 40 mg daily. This gave little relief After two days it was decided to discontinue treatment of the dog with antipsychosis drugs and to investigate a novel therapy. The decision was predicated upon the inventor's personal experience. Having endured depression nightly for more than two decades. The first time he consumed one 500 mg capsules of acetyl-L-carnitine in a "pop culture" effort to improve his memory. Depression ceased| And remained so as long as Alcar was consumed daily. It was thought, there may be a physiologic similarity between depression in humans and psychosis in dogs, the dog's owners agreed to add mg per pound body weight acetyl-L-carnitine orally morning and night to his treatment regimen for one week. The dog's psychosis began to diminish within two days. By the end of the week he no longer hid in the house, would eat from his food bowl, and trembling when he went outside was much less severe. Acetyl-L-carnitine therapy was continued but fluoxetine HCI dosage was reduced to 20 mg orally once daily. His fearfulness continued to diminish and he began to go on short walks. Twenty-one days later symptoms were so minimal that fluoxetine HCI was discontinued. Within a week his behavior and activity level were as normal as they had been three years previously. However, that day, while on a moderately long walk he suddenly collapsed, temporarily became unconscious and, unable to rise or walk, was carried home. The owner commented that on the previous day's walk a similar but less severe episode had taken place.
When examined at the hospital he was conscious but very depressed with no sign of anxiety. His pulse was weak, 200 beats per minute, and capillary refill time was four seconds. An electrocardiogram (ECG) tracing showed no arrhythmia but the T-wave was augmented with negative polarity. Because of symptoms: syncope, exercise intolerance, weak pulse, tachycardia, and prolonged capillary refill time the dog was diagnosed as suffering from cardiac failure. Sustained-release 500 mg procainamide orally morning and night was added to the acetyl-L-carnitine regimen. The following day, an ECG showed improvement. Amplitude of the T-wave was less but polarity was still negative. His demeanor was brighter and he was responsive to owner and surroundings. Within three days he could again walk for short distances without signs of distress. However, his exercise tolerance was sub-normal. It was decided to continue giving him the procainamide, for it seemed to have helped cardiac function, but replace acetyl-L-carnitine with L-carnitine, 5 mg per pound body weight orally morning and night, to see if it might further improve his level of physical activity. Following seven days of L-carnitine supplement, his level of physical activity was again normal and he was going for two-mile long walks. In an attempt to clarify whether the dog's activity level had returned to normal because of carnitine and its metabolic effects on heart muscle or the procainamide and its effect on cardiac impulse conduction, the latter was phased out through the ensuing week. During that time he continued to walk and run normally with no evidence of cardiac insufficiency. This indicated disturbed metabolism of myocardial cells must have caused the circulatory failure for the dog's level of activity improved most when he was given L-carnitine and it remained normal with deletion of procainamide. Daily treatment only with L-carnitine was continued. Then after 17 days without acetyl-L-carnitine, the owner called to report the dog's physical activity was normal but psychosis had returned. It appeared, on one hand, that acetyl-L-carnitine had improved the dog's psychic state but cardiac malfunction developed once his activity level increased. On the other hand, L-carnitine had corrected the circulatory failure without benefiting the psychosis. In an effort to correct the resurging psychotic state while preventing recurrence of heart failure acetyl-L-carnitine and L-carnitine were given to the dog. To evaluate their compatibility the two nutrients were mixed together as powders in equal parts as a dietary supplement to be added as a powder to the dog's food. Dosage was mg per pound body weight daily. While on the combination anxiety symptoms disappeared within five days and no further heart failure signs developed. The nutrient combination was continued and the dog behaved normally, running and playing, with no signs of fear or anxiety for two months after which time he was boarded at the hospital. While at the hospital he was closely observed, and judged to behave and function as normally as when he was three years younger.
EXAMPLE 6
The second case, an eight year old spayed mixed-breed shepherd, was presented with history of weakness of rear legs and back of several months duration. She spent most of her time lying down, even when eating. After lying she was slow to stand and moved stiffly as if weak or in pain, she could not jump as she had in the past, and after brief exercise she would be reluctant to move and panted excessively. She winced in pain from pressure on the gluteal region. Spinal radiographs showed moderate lesions of spondyloarthopathy only at the lumbo-sacral junction. There appeared to be atrophy of masticatory and longissimus muscles, for bones of head and spinal processes were prominent. Blood count and serum chemistries were all within normal parameters. Indirect fluorescent-antibody tests with the dog's serum obtained on day one reacted against rat sciatic nerve tissue were negative, for antibodies against nerve tissue skeletal muscle tests showed a weak nonspecific response to muscle fibers but there was no reaction to connective tissue or vascular elements. A Hep-2 test for serum antinuclear antibodies was negative. Biopsy of longissimus muscle on day two at the level of lumbar vertebrae L2 and 3 revealed about half of muscle mass atrophied or replaced by fat. The possibility of immune-mediated myositis prompted therapeutic testing with prednisone and azathioprine for ten days, beginning on day seven. During the course of treatment there was a slight improvement in the dog's ability to move about but the response was considered inconclusive. Based on poor clinical response to immune suppression and negative indirect fluorescent antibody tests for antibodies to skeletal muscle it was concluded her malady probably was other than immune-mediated myositis. Longissimus muscle biopsy specimens became available on day thirteen. They substantiated the conclusion that the dog's muscle weakness was not an immune mediated myopathy for there was no inflammatory reaction in the muscle. Instead, there was both muscle fiber atrophy and metaplasia of satellite cells to lipocytes. There was no evidence of ragged red fibers as seen in humans with MELAS.
On day twenty-four, L-carnitine mg, per pound body weight orally twice daily in her food was prescribed. After three weeks of this treatment, the owner reported the dog was much stronger, now being able to jump into a pickup truck. She could walk and run about normally without apparent pain or panting and she could get to her feet quickly after lying down and no longer lay down to eat. The dog's condition continued to be satisfactory while receiving L-carnitine daily. To compare effectiveness and possible biochemical interchange of two nutrients, acetyl-L-carnitine was substituted for L-carnitine on day one-hundred. Sixteen days later the owner reported the dog's weakness, panting, and pain on palpation of gluteal region had returned. It was concluded L-carnitine but not acetyl-L-carnitine effectively relieved the dog's symptoms. To investigate compatibility and effectiveness of the combined nutrients L-carnitine and acetyl-L-carnitine were mixed in equal amounts and dispensed to be added to the dog's food, mg per pound body weight once daily. Following seven days of this therapy the owner telephoned to say the dog's activity and demeanor were again normal, the same as they had been when the dog was receiving L-carnitine and before acetyl-L-carnitine alone was given.
This example demonstrates beneficial effects of the invention when used to treat a dog with a previously undescribed skeletal myopathy. L-carnitine alone produced progressive improvement over a three week period before reaching a stable plateau. When acetyl-L-carnitine was substituted for carnitine the dog's previous clinical condition was reinstated in less than three weeks indicating Alcar was ineffective. However, the fact the invention elevated symptoms of muscle weakness and pain after one week of therapy indicates synergism between the two metabolic cofactors.
EXAMPLE 7
The third dog, a cardiac case when presented was clinically typical of other large dogs seen in practice that have a cardiac arrhythmia, usually ventricular tachycardia, often with unsatisfactory response, to medical management. This case illustrates, that in addition to cardiac disease, skeletal muscle weakness and epileptiform seizures can be manifest simultaneous in one dog and all respond to an oral supplement of combined L-carnitine and acetyl-L-carnitine.
The eight year old spayed Siberian Husky, when presented had a history of episodes of grand mall seizures, muscle weakness, and hypothyroidism, she was receiving levothyroxin Na daily. Initially, seizures occurred every few months when they began five years previously. No medical basis was found for the convulsions and there was no evidence of other central nervous dysfunction. When seizure frequency became more than one a month the owner sought medical assistance and the dog was treated with 25% KBr solution, 1 ml per 15 pounds body weight, orally once daily which controlled seizures.
Muscle weakness had been a progressive condition for three years. Other than an inconclusive superficial clinical examination for lameness no effort had been made to ascertain cause of the weakness. In her daily life prior to admittance she had become so weak she had to be supported with a sling under her belly whenever she walked more than twenty yards.
The day before admittance to the hospital the dog seemed to the owner to have a seizure. He considered the episode to be an atypical convulsion. Symptoms were described as disorientation, weakness, and collapse. When presented at the hospital the dog was unable to stand and walk. She had to be carried from the car into the hospital. On examination her pulse was weak and irregular. Her creatinine phosphokinase was four times higher than normal indicating probable heart muscle injury. An ECG showed long periods of ventricular tachycardia, a severe often fatal form of heart arrhythmia, with intermittent periods in which rhythm was normal but R wave magnitude was diminished. The dog's immediate problem was diagnosed as cardiac failure and the previous day's episode, which the owner witnessed, was considered to be syncope caused by an episode of ventricular tachycardia. The dog was treated with lidocaine and propanalol intravenously, with this standard treatment it was impossible to convert the arrhythmia. As a last resort she was treated orally with 500 mg sustained release procainamide and, because of beneficial cardiac response to combined L-carnitine and acetyl-L-carnitine with a previous case the combination was administered orally mg per pound body weight. The same treatment was administered that evening and the following morning. The ECG after twenty-four hours of treatment no longer showed evidence of ventricular tachycardia but was in other respects similar to the previous day. She was alert and responsive, still weak but as functional as she had been before the syncope episode. She was eating well so the L-carnitine, acetyl-L-carnitine combination was mixed in her food and continued morning and night for one week at which time her ECG was nearly normal and the procainamide was stopped and the L-carnitine and acetyl-L-carnitine combination was supplemented once daily. She showed no further heart related symptoms.
Just as the dog's cardiac function responded to the supplement her muscle weakness also improved. Four weeks after commencing treatment with L-carnitine and acetyl-L-carnitine the owner reported the dog was more active than she had been in several years, now free of all support she was able to run rapidly and happily about the house and go for long walks. The ECG, at that time, day twenty-eight was normal. In addition to heart and muscle function improvement, her nervous system had improved. Because of her good spirits it was decided to phase out seizure controlling medications. Three months after stopping all seizure control medication, her health continued to be good. She was very active, her haircoat, which had been rough and ragged, had become luxurious and she had one mild seizure once each month since treatment with L-carnitine and acetyl-L-carnitine began.
Numerous modifactions on variations in practice of the invention in its several aspects as above described are expected to occur such limitations as are set out in appended claims should be placed there on. | A combination can be of L-carnitine and acetyl-L-carnitine administered orally or as parenteral injection in domesticated animals, especially pet animals, and humans for prevention or treatment of syndromes or diseases arising from dysfunctional energy metabolism. Syndromes involving skeletal and cardiac muscle benefited from L-carnitine, syndromes related to the central nervous system improved with acetyl-L-carnitine. Although the two cofactors do not substitute metabolically for each other effects of the combination are found to be synergistic. | 0 |
BACKGROUND OF THE INVENTION
Diesel fuel for use with internal combustion engines is popular for reasons of availability, price and efficiency. Diesel engines are well known for durability and longevity. However, the use of such fuel is not problem free, particularly in colder climates. This is due at least in part to the presence of paraffin, wax and water in the fuel in varying degrees depending on the geographical source of the fuel and the amount of refinement. At approximately 20° F., the paraffin can congeal and block the fuel filter with resultant engine starvation even after a period of engine operation. Water condensation can also cause engine problems.
In attempts to solve this problem, various devices have been used to heat the fuel prior to entry into or upon entry into the fuel filter to avoid congealing and permit the passage of the fuel to the fuel injectors. For example, some heaters are provided to preheat the fuel even while the engine is at rest in order to facilitate starting. Another device is interposed between the fuel filter mount and the fuel filter to heat the fuel as it passes into and out of the fuel filter. Many other devices have been proposed and are available for heating the fuel.
SUMMARY OF THE INVENTION
The invention relates to a device for heating or maintaining the temperature of diesel-type fuel as it passes through the fuel filter in order to avoid problems associated with congealing and condensation. A sheath or jacket has a sleeve to closely cover the fluid filter housing when installed on the fluid filter mount. The sleeve is formed of a thermal insulative material. A mounting ring is partially embedded in the sleeve and has fingers extending outwardly of the sleeve in an axial direction. The fingers are bendable about a portion of the filter housing in order to maintain the sleeve in place. A heating element can also be embedded in the side walls of the sleeve in order to selectively apply heat to the sleeve to be transmitted through the inner wall of the sleeve to the filter housing to supply heat to passing fuel. The heating element can be thermostatically operated or it can be manually switched on and off.
IN THE DRAWINGS
FIG. 1 is a diagrammatic view of an internal combustion diesel engine equipped with a fuel filter jacket and heater according to the invention;
FIG. 2 is an enlarged side elevational view of the fuel filter and jacket of FIG. 1 with portions broken away for purposes of illustration;
FIG. 3 is a reduced bottom plan view of the fuel filter and jacket of FIG. 2;
FIG. 4 is a sectional view of the fuel filter and jacket of FIG. 3 taken along the line 4--4 thereof;
FIG. 5 is a reduced sectional view of the fuel filter and jacket of FIG. 2 taken along the line 2--2 thereof;
FIG. 6 is a perspective view of a modification of a fuel filter jacket of the invention;
FIG. 7 is a side elevational view of the fuel filter jacket of FIG. 6;
FIG. 8 is an enlarged bottom view of the fuel jacket of FIG. 6;
FIG. 9 is a sectional view of the fuel filter and jacket of FIG. 7 taken along the line 9--9 thereof; and
FIG. 10 is another sectional view of the fuel filter and jacket of FIG. 7 taken along the line 10--10 thereof.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, there is shown in FIG. 1 a fuel filter jacket 10 installed on a fuel filter 11 connected in operative relationship to a diesel internal combustion engine 12 of the type having a cylinder block 13, a cooling radiator 14 and a fuel pump 15 mounted on the block 13. A fuel filter inlet line 17 delivers fuel from the fuel pump 15 to fuel filter 11 where it is filtered preparatory to passing through fuel outlet line 18 to fuel injectors (not shown) mounted on engine block 13 for discharging fuel into combustion chambers. Engine 12 can be of the type that burns hydrocarbon fuel, such as diesel fuel, whereby at times it is important that the fuel be maintained at a certain minimum temperature prior to introduction into the fuel filter 11 or fuel injectors.
As shown in FIGS. 2 and 4, fuel filter assembly 11 includes a fuel filter mount 19 and a removable, replaceable fuel filter element 21 carrying filtering media 22. Filter element 21 has a top wall 24 and a cylindrical cup-shaped housing 25 containing filter element or media 22 (see FIG. 4). Top wall 24 has a central threaded opening which receives an exteriorly threaded tubular fitting 26 connected to the bottom of filter mount 19. A pair of inlet tubes 28 extend downwardly from the top wall 24 and register with suitable openings in the bottom of filter mount 19 when top wall 24 is fully secured on fitting 26. Fuel traveling through the inlet 17 passes through the fuel filter mount 19 down through the inlet tubes 28. The fuel passes through the filtering media 22 then back through the central opening of fitting 26, which is connected to the fuel outlet line 18.
Fuel filter sheath or jacket 10 closely surrounds housing 25 of filter element 21. Jacket 10 includes a side wall forming a cylindrical sleeve 29 connected to a bottom wall 30. Sleeve 29 has an inside diameter to closely correspond to the outside diameter of the housing 25 of filter element 21 in order to fit over the housing 25 in snug relationship. The inside height of sleeve 29 or the distance between the inside surface of bottom wall 30 and the upper edge 31 of sleeve 29 generally corresponds to the side wall length of housing 25 of filter element 21. Sleeve 29 and bottom wall 30 are formed of a one piece, resilient, and heat insulative material, such as foam rubber, foam plastic and the like. A drain opening 32 is provided in bottom wall 30 to permit passage of condensate or other fluid products to the atmosphere. The inside and outside of sleeve 29 can be coated with flexible rubber to seal the surfaces of the foamed sleeve.
A mounting ring 34 is integral with sleeve 29 near the upper edge 31 to secure jacket 10 to filter element 21. Mounting ring 34 includes a base comprised as a cylindrical rim or band 35 embedded in sleeve 29 just beneath the upper edge 31 and preferably having a diameter just slightly larger than the diameter of the top wall 24 of filter element 21. Band 35 is split to allow the sleeve 29 to expand when it is forced on filter housing 25. Band 35 has a number of holes to allow the material of the sleeve to fix the band in the end of the sleeve. A plurality of vertical fingers 36 extend upward from band 35 and outwardly of the top edge 31 of sleeve 29. Fingers 36 can be integrally formed with the band 35 and are of a bendable metal. Fingers are generally flat tabs circumferentially spaced from each other. The space between adjacent tabs is generally equal. Fingers 36 are adapted to be bent around the upper edge of top wall 24 of filter element 21. In the configuration with jacket 10 installed on filter element 21, fingers 36 extend upward from band 25 beyond upper edge 31 of jacket 29 and are bent inwardly over the top edge of top wall 24 to secure jacket 10 on filter housing 25.
Jacket 10 has heating means to supply heat to filter element 21 to prevent coagulating of passing fuel which might otherwise block passage through filtering media 22. A heating element or wire 39 is embedded in sleeve 29 and forms a closed loop circumferentially around the side wall. Wire 39 is located adjacent the inner surface of sleeve 29. Element 39 is arranged in a series of side-by-side open or sinuate loops around sleeve 29. Element 39 is arranged is such a loop pattern in order to evenly distribute heat about the side wall 29. A thermal couple 40 disposed in element 39 regulates the maximum temperature achievable by the heating element. An electrical fitting 41 leads element 39 into and out of sleeve 29. A lead 43 extends to exterior controls 44 including thermostatic control 46, on-off switch 47 and power supply 49 which can be the usual vehicle battery.
In use of jacket 10, sleeve 29 is slipped over the housing 25 of the fuel filter element installed on fuel filter mount 19 with the fingers 36 initially in a straight or unbent condition. When the sleeve 29 and bottom wall 30 are properly positioned, the fingers 36 are bent over the top wall 24 of the fuel filter element. This serves to securely hold the jacket 10 in place. The heating element is energized to provide heat according to ambient conditions such that passing fuel will not congeal in the fuel filter element.
According to the form of the invention shown in FIGS. 7-10, there is provided a fuel filter jacket 50 for purposes of insulating a fuel filter element and conserving the heat retained in passing fuel in order to prevent congealing thereof and blockage of the fuel filter. Jacket 50 has a side wall forming a cylindrical sleeve 51 with an inside diameter sufficient to snugly accommodate the outside diameter of the housing of a fuel filter element. The lower portion of sleeve 51 is closed by a bottom wall 52 which can have a central opening 53 for discharge of condensate or other fluids. Sleeve 51 and bottom 52 are formed of a thermally insulative material, such as foam rubber, foam plastic, and the like. The inside height of sleeve 51 between the upper surface of bottom wall 52 and the upper edge 55 generally corresponds to the height of the side wall of the housing of a fuel filter element. The inside and outside surfaces of sleeve 51 can be coated with flexible rubber to seal the surfaces of the foamed sleeve.
A mounting split ring or base 57 associated with the upper portion of sleeve 51 includes a circular rim or band 58 embedded in the sleeve 51 just beneath the upper edge 54. The band 58 is split to allow sleeve 51 to expand and fit over the filter housing. A plurality of upstanding bendable fingers 59 extend upwardly from band 58 and outwardly of the top edge 54. Fingers 59 are adapted to be bended over the end wall of a fuel filter element.
In use, sleeve 51 is slipped over the outer wall or housing of a fuel filter element to the extent where the bottom of the element is proximate bottom wall 52 and the top of the element more or less aligns the upper edge 54 of sleeve 51. At that point, fingers 59 are bent over the top of the element as previously described to secure the jacket 50 in place. When so in place, the jacket 50 is operative to prevent heat loss from the fuel filter element to the surrounding atmosphere to assist in maintaining the heat in the passing fuel and prevent congealing of it. | A jacket for maintaining or adding heat to a diesel fuel-type fuel filter as fuel passes through the filter in order to decrease the incidence of congealing and avoid problems associated with condensation. The jacket includes a sleeve of thermally insulative material closely surrounding the fuel filter housing. A mounting ring has a base embedded in the jacket and mounting fingers extended axially from the upper edge of the sleeve. The mounting fingers are bendable over the top wall of the fuel filter element housing. Heating means embedded in the sleeve selectively provide heat to the fuel filter housing for transfer to passing diesel-type fuel. | 5 |
BACKGROUND OF THE INVENTION
A process for the catalytic oxidation of HCl gas is described in European Patent No. EP 233 773 B1, in which a HCl gas contaminated with organic impurities such as benzene, chlorobenzene and the like is prepurified for use in a Deacon process (catalytic HCl oxidation by means of oxygen). In the prepurification described therein, activated carbon is used as the adsorber and is regenerated after use. It is further proposed to regenerate the adsorber at elevated temperatures or under reduced pressure and optionally using an inert gas.
One disadvantage of such a process is that the production process and the HCl purification process must be interrupted for regeneration of the activated carbon bed. A further disadvantage of such a process is that the regeneration is conducted thermally or at reduced pressure, which is disadvantageous in terms of energy, or is carried out using an inert gas, which is expensive.
Adsorptive separation to remove contaminants from gas streams, particularly organic contaminants, is frequently used in chemical processing.
As adsorbents are used, they periodically require regeneration. During regeneration of an adsorbent, the adsorbent is conventionally heated and brought into contact with a regenerating gas stream. The adsorbed components thereby dissolve in the regenerating gas stream and the adsorbent is unloaded.
The achievable pity of the gas stream from which the contaminants are to be removed can depend greatly on the regeneration of the loaded adsorbent.
Conventional regeneration processes generally use heated inert gas or steam in order to introduce the required heat energy and the required regenerating gas stream into the system simultaneously. Steam can only be used in cases where moisture can be tolerated within the process. In the case of the working up of crude hydrogen chloride gas, attempts are made to avoid introducing water in order to prevent corrosion of apparatus that comes into contact with the product.
When inert gases (e.g. nitrogen, etc.) are used in regeneration, however, the amounts of gas that must be used to provide a continuous stream of fresh regenerative gas give rise to high costs. If, on the other hand, a circulatory regeneration system with inert gases is used, then components dissolved in the inert gases during regeneration of the adsorber must be depleted before recycling the inert gases to the circulatory system. Otherwise, the regeneration achieved would not be sufficient to provide the required process gas purities during the adsorption operation.
BRIEF SUMMARY OF THE INVENTION
The present invention relates, in general, to processes for working up gas streams, which are contaminated with one or more organic compounds, through adsorption, with regeneration of the adsorption medium. Various preferred embodiments of processes according to the present invention relate to the purification of process gases containing hydrogen chloride.
Various embodiments of the present invention can provide processes which are more advantageous in terms of energy and which, in particular, reduce the use of expensive inert gases during the regeneration of the adsorbers and permit a continuous process.
Various embodiments of the processes according to the present invention can provide reduced inert gas consumption in regenerative adsorption processes for process gas purification of gas streams contaminated with organic compounds.
One embodiment of the present invention includes processes which comprise:
providing a crude gas stream having a temperature not exceeding 40° C., the crude gas stream comprising at least one organic impurity; condensing at least a portion of the at least one organic impurity from the crude gas stream at a temperature not exceeding 0° C. to form a prepurified gas stream; and subjecting at least a portion, preferably substantially all, and more preferably the entirety, of the prepurified gas stream to adsorption on a first adsorption medium to provide a purified gas stream;
wherein the first adsorption medium is subjected to a regeneration comprising: (i) providing a circulating inert gas stream having a temperature of at least 100° C.; (ii) passing the circulating inert gas stream over the first adsorption medium to form an organic impurity-loaded inert gas stream; (iii) cooling the loaded inert gas stream to a temperature not exceeding 40° C.; (iv) condensing at least a portion of the organic impurity from the cooled, loaded inert gas stream to provide a prepurified circulating inert gas stream; subjecting at least a portion, preferably substantially all, and more preferably the entirety, of the prepurified circulating inert gas stream to adsorption on a second adsorption medium to provide a purified circulating inert gas stream; and recycling the purified circulating inert gas stream to the circulating inert gas stream. In various preferred embodiments, a portion of the purified circulating inert gas stream can be purged and a remainder of the purified circulating inert gas stream is then recycled to form the circulating inert gas stream.
Another embodiment of the present invention includes processes for removing organic components from a crude gas stream, which may optionally be hot, comprising:
A) adjustment of the crude gas stream that is to be purified to a temperature not exceeding 40° C.;
B) condensation of at least some of the organic components of the crude gas stream at a temperature not exceeding 0° C.;
C) subsequent, at least partial adsorption of the residual organic components that remain in the prepurified gas stream after the condensation, on a first adsorption medium;
D) subsequent heat exchange between the purified gas stream leaving the adsorption C) and the crude gas stream entering the process;
E) provision of the purified gas stream; characterized in that the adsorption medium mentioned under C) is subjected to a regeneration comprising the following steps:
F) connection of the adsorption medium to an inert gas circuit;
G) mixing a fresh inert gas stream and a purified recycled inert gas stream to provide a circulating inert gas stream and heating it to a temperature of at least 100° C., in particular in a heater;
H) subsequent passing of the heated circulating inert gas stream over the adsorption medium that is to be regenerated;
I) subsequent cooling of the circulating inert gas stream loaded with the organic components to a temperature not exceeding 40° C.;
J) subsequent condensation of at least some of the organic components of the circulating inert gas stream at a temperature not exceeding 0° C.;
K) subsequent adsorption of the residual organic components that remain in the circulating inert gas stream after the condensation J), in a second adsorption medium;
L) optional subsequent heat exchange between the thus purified circulating inert gas stream leaving the adsorption K) and the circulating inert gas stream entering the condensation J);
M) optional subsequent increase of the pressure of the purified circulating inert gas stream, in particular with the aid of a circulating gas compressor, in order to overcome any circulating gas pressure losses;
N) purge of a portion of the purified circulating inert gas stream and recycling a remainder of the purified circulating inert gas stream to the heater stage G).
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The foregoing summary, as well as the following detailed description of the invention, may be better understood when read in conjunction with the appended drawings. For the purpose of assisting in the explanation of the invention, there are shown in the drawings representative embodiments which are considered illustrative. It should be understood, however, that the invention is not limited in any manner to the precise arrangements and instrumentalities shown.
In the drawings:
FIG. 1 is a flow diagram of a process in accordance with one embodiment of the present invention; and
FIG. 2 is a flow diagram of a process in accordance with another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, the singular terms “a” and “the” are synonymous and used interchangeably with “one or more” and “at least one,” unless the language and/or context clearly indicates otherwise. Accordingly, for example, reference to “a gas stream” herein or in the appended claims can refer to a single gas stream or more than one gas stream. Additionally, all numerical values, unless otherwise specifically noted, are understood to be modified by the word “about.”
Suitable adsorption agents which can be used in an adsorption in accordance with the various embodiments of processes according to the present invention include, but are not limited to, activated carbon, zeolites, aluminum oxide, bentonite, silica gel and/or organometallic complexes. Activated carbon is preferred. Suitable types of apparatus for the production of an intensive gas-adsorbent contact are simple fixed beds, fluid beds, fluidized beds, or fixed beds movable as a whole.
Advantages of the adsorptive removal of components from gas streams include very high purities of the purified gas stream that can be achieved, and that, in the case of regenerative adsorption processes, it is possible to recover the organic components for targeted disposal or for returning to preceding preparation processes.
Various embodiments of processes according to the present invention can include providing an initial crude gas stream having a temperature exceeding 40° C. and cooling the initial crude gas stream to provide the crude gas stream having a temperature not exceeding 40° C. The temperature of an initial crude gas stream can be, in particular, up to 400° C., preferably up to 250° C., particularly preferably up to 150° C.
Preference is given to various processes which are characterized by the cooling of an initial crude gas stream, first in a cooler to a temperature not exceeding 45° C. Also preferably, cooling of an initial crude gas stream can take place in a second step, in particular in a recuperator, to a temperature not exceeding 40° C. In various particularly preferred embodiments of the processes according to the invention, heat exchange between the gas stream leaving the adsorption and the crude gas stream entering the process can take place in a recuperator. Cooling preferably takes place in a first step in a cooler to a temperature not exceeding 45° C. and in a second step in a recuperator to a temperature not exceeding 40° C.
In various preferred embodiments of the processes according to the invention, the second adsorption medium can be regenerated with the aid of another heated inert gas stream.
The process is particularly preferably used when the crude gas stream that is to be purified consists essentially of hydrogen chloride and/or the inert gas for the circulating inert gas stream consists essentially of nitrogen. As used herein, “Consists essentially of” with respect to hydrogen chloride content in the crude gas stream refers to a hydrogen chloride content of at least 80% by weight, more preferably at least 90% by weight, and most preferably at least 95% by weight. As used herein, “consists essentially of” with respect to nitrogen content in the circulating inert gas stream refers to a nitrogen content of at least 70% by weight, more preferably at least 80% by weight, and most preferably at least 90% by weight.
Organic components that can be separated from a crude gas stream in accordance with the various embodiments of the processes according to the present invention preferably include hydrocarbons and/or halogenated hydrocarbons, particularly preferably aromatic hydrocarbons such as benzene, toluene, xylenes and C 6 -C 12 -aliphatic compounds, and/or chlorinated hydrocarbons such as carbon tetrachloride, vinyl chloride and dichloroethane, and/or chlorinated aromatic hydrocarbons such as hexachlorobenzene, chlorobenzene and/or orthodichlorobenzene.
In various particularly preferred embodiments of the processes according to the invention, the adsorption can take place in at least two adsorption stages. Particularly preferably, the first adsorption medium of the first stage is regenerated with the aid of a partial stream of the crude gas stream, and the loaded crude gas partial stream is optionally combined with the crude gas stream entering the condensation.
A preferred modification of the processes according to various embodiments of the invention can include regeneration of the adsorption medium of the first stage from time to time by means of an inert gas, optionally in a single pass, alternately with regeneration by means of the crude gas partial stream. In the case of adsorption in two or more stages, inert gas is particularly preferably passed for regeneration starting from the last adsorption stage via the series of adsorbers to the first adsorber.
The processes according to the invention are particularly preferably used when the hydrogen-chloride-containing purified gas stream is used further in a production process for the preparation of chlorine from hydrogen chloride and oxygen, in particular in a catalyzed gas-phase oxidation of hydrogen chloride with oxygen or in a non-thermal reaction of hydrogen chloride and oxygen. Coupling with the catalyzed gas-phase oxidation of hydrogen chloride with oxygen Deacon process) is particularly preferred.
As already described above, the catalytic process known as the Deacon process is preferably used in combination with the processes according to the invention. In a Deacon process, hydrogen chloride is oxidized to chlorine with oxygen in an exothermic equilibrium reaction, with the formation of steam. The reaction temperature is conventionally from 150 to 500° C. and the conventional reaction pressure is from 1 to 25 bar. Because the reaction is an equilibrium reaction, it is advantageous to work at the lowest possible temperatures at which the catalyst still has sufficient activity. It is also advantageous to use oxygen in over-stoichiometric amounts relative to the hydrogen chloride. A two- to four-fold oxygen excess, for example, is conventional. Because there is no risk of losses of selectivity, it can be economically advantageous to work at a relatively high pressure and accordingly with a longer residence time as compared with normal pressure.
Suitable preferred catalysts for the Deacon process comprise ruthenium oxide, ruthenium chloride or other ruthenium compounds on silicon dioxide, aluminum oxide, titanium dioxide or zirconium dioxide as support. Suitable catalysts can be obtained, for example, by applying ruthenium chloride to the support and then drying or drying and calcining. In addition to or instead of a ruthenium compound, suitable catalysts can also comprise compounds of other noble metals, for example gold, palladium, platinum, osmium, iridium, silver, copper or rhenium. Suitable catalysts can farther comprise chromium(III) oxide.
The catalytic hydrogen chloride oxidation can be carried out adiabatically or, preferably, isothermally or approximately isothermally, discontinuously, but preferably continuously as a fluid or fixed bed process, preferably as a fixed bed process, particularly preferably in tubular reactors on heterogeneous catalysts at a reactor temperature of from 180 to 500° C., preferably from 200 to 400° C., particularly preferably from 220 to 350° C., and a pressure of from 1 to 25 bar (from 1000 to 25,000 hPa), preferably from 1.2 to 20 bar, particularly preferably from 1.5 to 17 bar and especially from 2.0 to 15 bar.
Conventional reaction apparatuses in which the catalytic hydrogen chloride oxidation is carried out are fixed bed or fluidized bed reactors. The catalytic hydrogen chloride oxidation can preferably also be carried out in a plurality of stages.
In the case of the adiabatic, isothermal or approximately isothermal procedure, it is also possible to use a plurality of reactors, that is to say from 2 to 10, preferably from 2 to 6, particularly preferably from 2 to 5, especially 2 or 3 reactors, connected in series with intermediate cooling. The hydrogen chloride can either be added in its entirety, together with the oxygen, upstream of the first reactor, or distributed over the various reactors. This series connection of individual reactors can also be combined in one apparatus.
In a further preferred form of a device suitable for the process there is used a structured bulk catalyst in which the catalytic activity increases in the direction of flow. Such structuring of the bulk catalyst can be effected by variable impregnation of the catalyst support with active substance or by variable dilution of the catalyst with an inert material. As the inert material there can be used, for example, rings, cylinders or spheres of titanium dioxide, zirconium dioxide or mixtures thereof aluminum oxide, steatite, ceramics, glass, graphite, stainless steel or nickel alloys. When catalyst shaped bodies are used, as is preferred, the inert material should preferably have similar outside dimensions.
Suitable catalyst shaped bodies are shaped bodies of any shape, preferred shapes being lozenges, rings, cylinders, stars, cart wheels or spheres and particularly preferred shapes being rings, cylinders or star-shaped extrudates.
Suitable heterogeneous catalysts are in particular ruthenium compounds or copper compounds on support materials, which can also be doped, with preference being given to optionally doped ruthenium catalysts. Examples of suitable support materials are silicon dioxide, graphite, titanium dioxide of rutile or anatase structure, zirconium dioxide, aluminum oxide or mixtures thereof, preferably titanium dioxide, zirconium dioxide, aluminum oxide or mixtures thereof, particularly preferably γ- or δ-aluminum oxide or mixtures thereof.
The copper or ruthenium supported catalysts can be obtained, for example, by impregnating the support material with aqueous solutions of CuCl 2 or RuCl 3 and optionally of a promoter for doping, preferably in the form of their chlorides. Shaping of the catalyst can take place after or, preferably, before the impregnation of the support material.
Suitable promoters for the doping of the catalysts are alkali metals such as lithium, sodium, potassium, rubidium and cesium, preferably lithium, sodium and potassium, particularly preferably potassium, alkaline earth metals such as magnesium, calcium, strontium and barium, preferably magnesium and calcium, particularly preferably magnesium, rare earth metals such as scandium, yttrium, lanthanum, cerium, praseodymium and neodymium, preferably scandium, yttrium, lanthanum and cerium, particularly preferably lanthanum and cerium, or mixtures thereof.
The shaped bodies can then be dried and optionally calcined at a temperature of from 100 to 400° C., preferably from 100 to 300° C., for example, under a nitrogen, argon or air atmosphere. The shaped bodies are preferably first dried at from 100 to 150° C. and then calcined at from 200 to 400° C.
The hydrogen chloride conversion in a single pass can preferably be limited to from 15 to 90%, preferably from 40 to 85%, particularly preferably from 50 to 70%. After separation, some or all of the unreacted hydrogen chloride can be fed back into the catalytic hydrogen chloride oxidation. The volume ratio of hydrogen chloride to oxygen at the entrance to the reactor is preferably from 1:1 to 20:1, preferably from 1:1 to 8:1, particularly preferably from 1:1 to 5:1.
The heat of reaction of the catalytic hydrogen chloride oxidation can advantageously be used to produce high-pressure steam. This can be used to operate a phosgenation reactor and/or distillation columns, in particular isocyanate distillation columns.
In a further step, the chlorine that has formed is separated off. The separation step conventionally comprises a plurality of stages, namely the separation and optional recycling of unreacted hydrogen chloride from the product gas stream of the hydrogen chloride oxidation, drying of the resulting stream containing substantially chlorine and oxygen, and the separation of chlorine from the dried stream.
The separation of unreacted hydrogen chloride and of steam that has formed can be carried out by removing aqueous hydrochloric acid from the product gas stream of the hydrogen chloride oxidation by cooling. Hydrogen chloride can also be absorbed in dilute hydrochloric acid or water.
The invention will now be described in further detail with reference to the following non-limiting examples.
EXAMPLES
Example 1
Referring to FIG. 1 , a process in accordance with an embodiment of the present invention is depicted, which provides high purity of the regenerating gas, and hence a high degree of regeneration of the adsorber, while at the same time, the amount of inert gas consumed is minimal.
As is shown in FIG. 1 , the regenerating gas stream is guided in a circuit in the process according to the invention, and the amount of inert gas consumed is thus minimized.
An initial crude gas stream 1 is precooled in a cooler 21 and passed through the recuperator 22 to provide a crude gas stream. In this example, the initial crude gas stream comprised a hydrogen chloride gas from a TDI production. Organic impurities such as chlorobenzene, hexachlorobenzene, and/or orthodichlorobenzene are condensed in the condenser 23 and discharged as stream 8 .
The prepurified crude gas 2 is passed over an adsorber bed 24 of activated carbon, and the purified gas stream 3 of hydrogen chloride is passed via the recuperator 22 to undergo heat exchange with incoming initial crude gas 1 and is discharged as product stream 4 which may then be oxidized to chlorine in a Deacon process (not shown).
The loaded adsorber bed 24 ′, which is operated alternately with adsorber bed 24 , is purified with an inert gas 6 which is composed of fresh inert gas 5 and a return stream 10 and is heated in the heat exchanger 25 .
After passing through the adsorber 24 ′, the loaded regenerating gas stream is cooled down in a precooler 27 . Further cooling then takes place in a recuperator 28 . The regenerating gas stream is subsequently cooled further in a low-temperature condenser 29 . During this cooling, a substantial part of the organic components contained in the circulating regenerating gas is conveyed away and combined with the stream 8 . In accordance with the thermodynamic equilibrium, however, a proportion of organic components corresponding to the vapor pressure of the organic components in question will still remain in the gas phase. This proportion can be reduced somewhat by the choice of appropriately low temperatures or high process pressures.
The residual amounts of organic components that remain in the gas stream after the low-temperature condensation 29 are separated off in a subsequent adsorber bed 30 . Heat exchange of the purified inert gas 15 with the loaded inert gas leaving the precooler 27 then takes place in the recuperator 28 , The purified inert gas stream 9 present downstream of the recuperator 28 is then fed to a circulating gas compressor 33 , with the aid of which the pressure losses in the regeneration circuit are overcome.
If the circulating gas adsorber 30 is loaded, it is replaced by the adsorber 31 and switched to regeneration operation. To this end, fresh inert gas 13 is heated in heat exchanger 32 and passed over the adsorber 31 in the opposite direction to the direction of flow during the loading phase. The loaded regenerating gas stream 12 is discharged from the system.
The regenerative adsorption process according to this embodiment of the invention for removing organic components from gas streams accordingly permits reduced inert gas consumption for the regeneration by the provision of a circulating gas procedure for the regenerating gas with at the same time high degrees of regeneration owing to the use of a circulating gas adsorber and the high circulating gas purities achieved thereby. Furthermore, the use of a circulating gas adsorber allows components that are not condensable in the low-temperature condensation to be discharged, and the accumulation thereof in the process is thus reduced or prevented.
The inert gas feed 5 into the regeneration circuit shown in FIG. 1 can serve to maintain the pressure, to flush the system or alternatively to discharge components which otherwise accumulate. Discharge can take place via stream 11 . Feed and discharge can, however, optionally also take place at any other positions in the regenerating gas circuit.
Example 2
Referring to FIG. 2 , an additional embodiment of a process according to the present invention for making a saving in terms of the inert gas used for the regeneration is depicted and includes using heated process gas for the partial regeneration of the adsorbers. This embodiment employs a two-stage, redundant adsorber unit 24 , 26 or 24 ′, 26 ′.
In adsorption mode, the crude gas 1 here too passes through the cooling and condensation stages 21 , 22 and 23 which have already been described above with reference to FIG. 1 , and in which some of the organic components contained in the gas stream are removed. The prepurified crude gas 2 from stage 23 is fed to a two-stage adsorption 24 , 26 , where some or all of the remaining organic components are separated off.
The embodiment depicted in FIG. 2 employs a two-stage adsorption because in regeneration operation the first adsorption stage 24 ′ is only partially regenerated with the heated partial stream 7 of the crude gas, and the required purities in the process gas can only be achieved by a second adsorption stage 26 ′ with an increased degree of regeneration.
The purified gas 3 from adsorber 26 is subjected to heat exchange with the crude gas 1 in recuperator 22 . After that it is provided as stream 4 to a Deacon-process (not shown in FIG. 2 ) where it is oxidized to chlorine.
As is shown in FIG. 2 , for regeneration of the first adsorption stage, some of the still untreated crude gas is heated and applied to the first stage 24 ′ of the adsorption. Depending on the temperature and the organic load of the process gas, the first adsorption stage 24 ′ is partially regenerated thereby. Complete regeneration is not achieved because of the preloading of the process gas stream.
The loaded partial stream 14 of process gas used for partial regeneration is then mixed with the crude gas stream 1 again.
Regeneration of the second adsorption stage takes place with inert gas either in a single pass (not shown in FIG. 2 ) or by recycling (shown in FIG. 2 ). As already described in example 1, the loaded adsorber 26 ′ (that is operated alternately with adsorber 26 ) is regenerated with an inert gas 6 that is composed of a fresh inert gas 5 and a recycled stream 10 . Streams 5 and 10 are beforehand heated in a heat exchanger 25 . After passing adsorber 26 ′ the loaded regenerating gas stream flows through the apparatuses 27 , 28 and 29 as already described in example 1. There, a considerable amount of the organic load is separated off, conveyed away and combined with stream 8 . In accordance with the thermodynamic equilibrium, however, a proportion of organic components corresponding to the vapor pressure of the organic components in question will still remain in the gas phase. This proportion can be reduced somewhat by the choice of appropriately low temperatures or high process pressures.
The residual amounts of organic components that remain in the gas stream after the low-temperature condensation 29 are separated off in a subsequent adsorber bed 30 . Heat exchange of the purified inert gas 15 with the loaded inert gas leaving the precooler 27 then takes place in the recuperator 28 . The purified inert gas stream 9 present downstream of the recuperator 28 is then fed to a circulating gas compressor 33 to overcome pressure losses in the regeneration circuit.
If the circulating gas adsorber 30 is loaded, it is replaced by the adsorber 31 and switched to regeneration operation. To this end, fresh inert gas 13 is heated in heat exchanger 32 and passed over the adsorber 31 in the opposite direction to the direction of flow during the loading phase. The loaded regenerating gas stream 12 is discharged from the system.
The inert gas feed 5 into the regeneration circuit shown in FIG. 2 can serve to maintain the pressure, to flush the system or alternatively to discharge components which otherwise accumulate. Discharge can take place via stream 11 . Feed and discharge can, however, optionally also take place at any other positions in the regenerating gas circuit
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. | Process for providing a purified gas stream, comprising: providing a crude gas stream comprising an organic impurity; condensing at least a portion of the impurity from the gas stream to form a prepurified gas stream; and subjecting the prepurified stream to adsorption on a first adsorption medium; wherein the first medium is subjected to a regeneration comprising: providing a circulating inert gas stream having a temperature of at least 100° C.; passing the circulating inert gas stream over the first medium to form an organic impurity-loaded inert gas stream; cooling the loaded stream; condensing at least a portion of the organic impurity from the cooled stream to provide a prepurified circulating inert gas stream; subjecting the prepurified gas stream to adsorption on a second adsorption medium to provide a purified circulating inert gas stream; and recycling the purified gas stream to the circulating inert gas stream. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] The invention relates to holding devices and more particularly to a holder for securely holding one or two portable electronic devices with improved characteristics.
[0003] 2. Description of Related Art
[0004] A wide variety of electronic products are commercially available due to the advancement of science and technology. One important feature of these products is that they are portable. Such portable electronic devices include, but not limited to, cellular phones, PDAs (personal digital assistants), palm type game machines, and tablet computers. Moreover, for laptops its keyboard is thin and may incorporate a touch pad or a trackball. These portable electronic devices may be actuated by wire (e.g., USB (universal serial bus)) or wireless (e.g., RF (radio frequency) or Bluetooth) technology.
[0005] These portable electronic devices are relatively expensive and advanced products. Thus, how to protect them in transport or use is an important issue. There are many different types of product for protecting portable electronic devices are available in the market. However, such products are disadvantageous because they are inferior in quality, not durable, awkward to carry, inconvenience in use, etc. Thus, the need for improvement still exists.
SUMMARY OF THE INVENTION
[0006] It is therefore one object of the invention to provide a holder for holding portable electronic devices comprising a main support body being a rectangular rigid plate and comprising an upwardly extending closed, rectangular, flexible flange on a top surface; a main support member being hingedly secured to a rear end of the main support body, the main support member being a rectangular rigid plate and comprising an extending closed, rectangular, flexible flange on a front surface; a support leg being hingedly secured to a transverse part of a back of the main support member, the support leg being a rectangular rigid plate; and at least one connecting strap each extending from a bottom edge of the support leg to be releasably secured to a back of the main support body, thereby adjusting a tilt angle of the support leg with respect to the main support member.
[0007] The above and other objects, features and advantages of the invention will become apparent from the following detailed description taken with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a holder according to a first preferred embodiment of the invention, two portable electronic devices to be held thereon;
[0009] FIG. 2 is another perspective view of the holder but viewing from an opposite angle;
[0010] FIG. 3 is a longitudinal sectional view of the holder with both the portable electronic devices being held thereon in an open position;
[0011] FIGS. 4 and 5 are views similar to FIG. 3 showing the holder being collapsed for saving storage space;
[0012] FIG. 6 is a longitudinal sectional view of a holder according to a second preferred embodiment of the invention in an open position;
[0013] FIG. 7 is a perspective view of the support leg and the connecting member of FIG. 6 ;
[0014] FIG. 8 is a perspective view of the holder of FIG. 6 viewing from a rear, bottom direction;
[0015] FIG. 9 is a view similar to FIG. 6 showing the holder being collapsed for saving storage space;
[0016] FIG. 10 is a longitudinal sectional view of a holder according to a third preferred embodiment of the invention in an open position;
[0017] FIG. 11 is a rear view of the holder of FIG. 10 ;
[0018] FIG. 12 is a longitudinal sectional view of a holder according to a fourth preferred embodiment of the invention in an open position;
[0019] FIG. 13 is a rear view of the holder of FIG. 12 ;
[0020] FIG. 14 is a sectional view taken along line X-X of FIG. 13 ; and
[0021] FIG. 15 is a perspective view of the holder of FIG. 1 with one portable electronic device being rested upon the tilted main support member and the other portable electronic device being retained in the recess of the main support body.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Referring to FIGS. 1 to 5 , a holder 10 for holding portable electronic devices in accordance with a first preferred embodiment of the invention comprises a main support body 11 , a main support member 16 , and a support leg 19 as discussed in detail below.
[0023] The main support body 11 is a rectangular rigid plate. The main support body 11 has an upwardly extending closed, rectangular, flexible flange 12 . A rectangular recess 121 is defined by the flange 12 . The flange 12 is made of elastomeric material so that an electronic input device 50 may be retained in the recess 121 . The electronic input device 50 can be a thin keyboard incorporating a touch pad or a trackball. A back 13 of the main support body 11 is provided with a plurality of disc magnetic members 131 . A flexible hinge 15 is provided on a rear edge of the main support body 11 . The main support member 16 extends outward from the hinge 15 so that the main support member 16 may be closed onto the main support body 11 or open with respect to the main support body 11 by pivoting about the hinge 15 .
[0024] The main support member 16 is a rectangular rigid plate. The main support member 16 has an extending closed, rectangular, flexible flange 17 . A rectangular recess 171 is defined by the flange 17 . The flange 17 is made of elastomeric material so that an electronic processing device 60 may be retained in the recess 171 . The electronic processing device 60 can be a cellular phone, a PDA, or a tablet computer. The support leg 19 is provided on a transverse central portion of a back 18 of the main support member 16 .
[0025] The support leg 19 is a rectangular rigid plate. The support leg 19 comprises a top edge 192 hingedly secured to the transverse central portion of the back 18 of the main support member 16 by stitching. A bottom edge 191 of the support leg 19 is adapted to rest upon a planar surface (e.g., desk top). A straight connecting strap 14 extends from a central portion of the bottom edge 191 . The other open end portion of the connecting strap 14 is provided with a plurality of spaced disc magnetic members 141 so that the connecting strap 14 may be secured to the back 13 of the main support body 11 by magnetically adhering to the disc magnetic member 131 . Positions of the disc magnetic members 141 secured to the back 13 can be adjusted as desired. Thus, a tilt angle of the support leg 19 with respect to the main support member 16 can be adjusted. This arrangement enables a user to comfortably view the electronic processing device 60 in an optimum tilt angle. Alternatively, the connecting strap 14 and the back 13 of the main support body 11 may be implemented as a hook and hoop fastener for saving cost and other beneficial purposes.
[0026] In the invention, the electronic input device 50 and the electronic processing device 60 can be communicated by wire (e.g., USB) or wireless (e.g., RF or Bluetooth) technology.
[0027] For closing the holder 10 , a user may unfasten the connecting strap 14 and then clockwise pivot same to engage the support leg 19 with the back 18 of the main support member 16 . Also, engage the main support member 16 with the main support body 11 (see FIGS. 3 and 4 ). Next, continuously clockwise pivot the connecting strap 14 and bent same until one of the disc magnetic members 141 is secured to one of the disc magnetic members 131 with the connecting strap 14 being tightly stretched (see FIGS. 4 and 5 ). Both the electronic processing device 60 and the electronic input device 50 are protected by the holder 10 in a storage position.
[0028] Referring to FIGS. 6 to 9 , a holder 20 for holding portable electronic devices in accordance with a second preferred embodiment of the invention is shown. The characteristics of the second preferred embodiment are substantially the same as that of the first preferred embodiment except the following:
[0029] The holder 20 comprises a main support body 21 , a main support member 26 , and a support leg 29 as discussed in detail below. The support leg 29 is a rectangular rigid plate. The support leg 29 comprises a bottom edge 293 adapted to rest upon a planar surface (e.g., desk top). A rectangular connecting plate 25 has one end hingedly secured to the bottom edge 293 . The other end of the connecting plate 25 is connected to the back of the main support body 21 . The support leg 29 further comprises a curved member 292 on a center of a top edge, and a transverse ridge 291 on one end of the curved member 292 . The curved member 292 is shaped to complimentarily engage with an extending closed, rectangular, flexible flange 27 of the main support member 26 when the holder 20 is closed in a storage position (see FIG. 9 ). The ridge 291 is adapted to insert in one of a plurality of parallel grooves 261 on the back of the main support member 26 . The ridge 291 can be retained by any one of the grooves 261 means that the electronic processing device 60 on the main support member 26 can be disposed in different angles with respect to the main support body 21 (i.e., different tilt angles). This arrangement enables a user to comfortably view the electronic processing device 60 in an optimum tilt angle.
[0030] A rectangular rigid plate 28 is fixedly provided on a lower portion of the main support member 26 just between the grooves 261 and the bottom edge of the main support member 26 . The connecting plate 25 is adapted to rest upon the rigid plate 28 when the holder 20 is closed. Moreover, a closed elastic strap 23 may be used to wrap around the front portions of the main support body 21 and the main support member 26 in the closed position of the holder 20 (see FIGS. 8 and 9 ). The provision of the elastic strap 23 can ensure the holder 20 and the device(s) (e.g., electronic input device 50 and/or electronic processing device 60 ) being retained in a protected state.
[0031] Referring to FIGS. 10 and 11 , a holder 30 for holding portable electronic devices in accordance with a third preferred embodiment of the invention is shown. The characteristics of the third preferred embodiment are substantially the same as that of the first preferred embodiment except the following:
[0032] The holder 30 comprises a main support body 31 , a main support member 36 , and two spaced, parallel support legs 39 as discussed in detail below. The support leg 39 is a rectangular plate. The support leg 39 comprises a pivot 392 on a top edge adapted to hingedly secure to a back of the main support member 36 . A bottom end of the support leg 39 is adapted to rest upon a planar surface (e.g., desk top). This means that tilt angle of the electronic processing device 60 on the main support member 36 with respect to the main support body 31 can be adjusted (i.e., different tilt angles). This arrangement enables a user to comfortably view the electronic processing device 60 in an optimum tilt angle. Moreover, an intermediate disc magnetic member 393 is provided on the support leg 39 . The disc magnetic member 393 is adapted to adhere to one of two transversely spaced disc magnetic members 361 when the support leg 39 is engaged with a back of the main support member 36 in a storage position of the holder 30 .
[0033] Referring to FIGS. 12 to 14 , a holder 40 for holding portable electronic devices in accordance with a fourth preferred embodiment of the invention is shown. The characteristics of the fourth preferred embodiment are substantially the same as that of the third preferred embodiment except the following:
[0034] The holder 40 comprises a main support body 41 , a main support member 46 , and a support leg 49 as discussed in detail below. The support leg 49 is a rod-like member. A pivot pin 47 is provided on a back of the main support member 46 . A gear 471 , as one portion of a ratchet, is provided on the periphery of the pivot pin 47 . the support leg 49 comprises an annular hole 491 at a top end, the hole 491 being put on the gear 471 , a pawl 492 provided on the inner surface of the hole 491 , a lever 494 distal the pawl 492 , and an elastic member (e.g., helical spring) 493 biased between the lever 494 and the back of the pawl 492 . The front of the pawl 942 is formed with a plurality of teeth which are adapted to engage with the teeth of the gear 471 . A pivoting operation (as indicated by the upper arrow) of the lever 494 may compress the elastic member 493 to push the pawl 492 to pivotably move the gear 471 . As such, an angle of the support leg 49 with respect to the main support member 46 is changed. A reverse pivoting operation (as indicated by the lower arrow) will return the lever 494 to its original position with the engagement of the pawl 492 and the gear 471 remained unchanged. The above two steps can be performed repeatedly until a desire tilt angle of the support leg 49 with respect to the main support member 46 is obtained. Further, the bottom end of the support leg 49 is rested upon a planar surface (e.g., desk top). This arrangement enables a user to comfortably view the electronic processing device 60 in an optimum tilt angle.
[0035] Referring to FIG. 15 , the electronic processing device 60 may be alternatively rested upon the tilted flange 17 and the electronic input device 50 may be retained by the flange 12 in another configuration of use.
[0036] While the invention has been described in terms of preferred embodiments, those skilled in the art will recognize that the invention can be practiced with modifications within the spirit and scope of the appended claims. | A holder for holding portable electronic devices includes a main support body being a rectangular rigid plate and comprising an upwardly extending closed, rectangular, flexible flange on a top surface; a main support member being hingedly secured to a rear end of the main support body, the main support member being a rectangular rigid plate and comprising an extending closed, rectangular, flexible flange on a front surface; a support leg being hingedly secured to a transverse part of a back of the main support member, the support leg being a rectangular rigid plate; and at least one connecting strap each extending from a bottom edge of the support leg to be releasably secured to a back of the main support body, thereby adjusting a tilt angle of the support leg with respect to the main support member. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional application 60/405,494 filed Aug. 23, 2002; and U.S. application Ser. No. 10/419,462, filed Apr. 21, 2003.
FIELD OF THE INVENTION
[0002] The present invention relates to assays for blood levels of one or more thrombospondin fragments as a diagnostic test for cancers and other diseases, the use of such fragments and/or derivatives thereof to generate specific antibodies and other binding agents and/or to use as calibrators, competitors, and/or indicators in an assay, and to the fragments themselves.
BACKGROUND OF THE INVENTION
[0003] Thrombospondin (TSP), also known as TSP-1, is a multimeric glycoprotein comprised of identical monomers. The monomers migrate at an apparent molecular weight of approximately 185 kDa in SDS-polyacrylamide electrophoretic gels under reducing conditions. The predominant multimer is a trimer, which migrates at an apparent molecular weight of approximately 450 kDa on non-reducing gels. The molecular weights by sedimentation equilibrium are similar, at 135 kDa for monomers and 420 kDa for trimers. The predicted molecular weight from just the sequence of amino acyl residues in the monomer is 127,524 Da, which does not include contributions from glycosylation and β-hydroxylation. The thrombospondin glycoprotein is produced by platelets and is released upon platelet activation from platelet α-granules, along with many other proteins, such as platelet-derived growth factor, β-thromboglobulin, fibronectin, fibrinogen, and platelet factor-4 (see Chapter 1, “An introduction to the thrombospondins” in The Thrombospondin Gene Family by J C Adams, R P Tucker, & J Lawler, Springer-Verlag: New York, 1995, pp. 1-9, but especially p. 2; and Chapter 3, “The secondary and tertiary structure of the thrombospondins,” ibidem pp. 43-56, especially Table 3.1). Thrombospondin is known to be involved in biological processes such as cell adhesion, proliferation and chemotaxis. It has also been reported that thrombospondin may be involved in the progression of malignant tumors. Furthermore, thrombospondin has been reported to be highly expressed in many human malignant tissues and in surrounding stroma and/or endothelium and has been reported to be present in higher than normal levels in the plasma of cancer patients. (e.g., Qian and Tuszynski, Proc. Soc. Exp. Biol. Med., 212:199-207, 1996; de Fraipont F et al. Trends Mol. Med., 7:401-407, 2001).
[0004] Despite the foregoing, as for any potential diagnostic test, it would be desirable to increase the specificity and sensitivity of such tests. To that end, the present inventor has discovered that thrombospondin is present in the blood and blood plasma in relatively small amounts compared to fragments of thrombospondin, and this finding is true in the blood and blood plasma of cancer patients as well. This discovery provided a basis for the present inventions related to novel diagnostic assays that are more specific, more sensitive, more easily calibrated, and in some cases distinguish these thrombospondin fragments from each other and from thrombospondin itself
BRIEF SUMMARY OF THE INVENTION
[0005] Important aspects of the invention are diagnostic methods and related kits that are based on the detection and quantification of thrombospondin fragments and/or thrombospondin in bodily fluids, especially plasma. Foremost among those diagnostic methods are those that detect or monitor the status of a cancer.
[0006] Aspects of the invention closely related to the diagnostic methods are thrombospondin fragments that are detected in the plasma, thrombospondin fragments that can be used to induce an antibody of interest for use in a diagnostic method or can be used in a competition-type or non-competitive diagnostic assay.
Thrombospondin Fragments of the Invention
[0007] In one aspect, the invention is a purified thrombospondin fragment that has been extracted from a bodily fluid, especially plasma, said fragment being one within a molecular weight range selected from the group consisting of 80 to 110 kDa, 40 to 60 kDa, and 20 to 35 kDa, wherein the size in kDa is that determined by gel electrophoresis after disulfide bond reduction. Their uses include, but are not limited to, a) the induction of an antibody of interest, b) induction of an antibody for a diagnostic method, c) use in a competition-type diagnostic assay, d) as a reference molecule in an assay for a thrombospondin fragment or fragments or thrombospondin of human subjects, and e) the immunization of an animal. In a closely related aspect, the invention is a polypeptide or modified polypeptide, made by recombinant and/or chemical techniques, that has the identical primary structure as one of said purified thrombospondin fragments or a portion thereof. Such chemical techniques include, but are not limited to, glycosylation, β-hydroxylation, alkylation and reduction.
[0008] In particular embodiments, the fragment's molecular weight is one within a molecular weight range selected from the group consisting of 80 to 95 kDa, 47 to 53 kDa, and 27 to 33 kDa. Specific examples of fragment molecule weights are 85, 90, 50, and 30 kDa. Preferably, the fragment is one found in human plasma.
[0009] In a related aspect, the invention is a purified and/or synthetic thrombospondin fragment or portion thereof, said fragment being one that starts between amino acid I-165 (just after the N12/I peptide) and V-263 (the start of the procollagen homology domain), inclusive (i.e., inclusive of I-165 and V-263), and ends between amino acid K-412 (the end of the reported collagen type V-binding region) and I-530 (the end of the domain of type 1 repeats), inclusive. Preferred are such fragments that start at between N-230 and G-253, inclusive (at or near the start of the domain of interchain disulfide bonds, I-241, which is the first residue downstream [meaning towards the C-terminus of the full protein] of a predicted cleavage site for chymotrypsin and/or a chymotrypsin-like protease), and end at between V-400 and S-428, inclusive (at or near a predicted chymotrypsin cleavage site, F-414, that falls two residues after the end of the collagen type V-binding region), said portion being at least 3 amino acyl acids in length (preferably at least 4 amino acyl residues in length, more preferably at least 6 amino acyl residues).
[0010] In a further related aspect, the invention is a purified and/or synthetic thrombospondin fragment or portion thereof, said fragment being one that starts between amino acid I-165 (just after the N12/I peptide) and V-263 (the start of the procollagen homology domain), inclusive, and ends between amino acid I-530 (the end of the type 1 repeats) and R-733 (the end of the first type 3 repeat), inclusive. Preferably such a fragment starts between N-230 and G-253, inclusive, and ends between D-527 and S-551, inclusive, which is at or near a predicted chymotrypsin cleavage site, F-539, in the first type 2 repeat; said portion being at least 3 amino acyl acids in length (preferably at least 4 amino acyl residues in length, more preferably at least 6 amino acyl residues).
[0011] In a still further related aspect, the invention is a purified and/or synthetic thrombospondin fragment or portion thereof, said fragment being one that starts between amino acid I-165 (just after the N12/I peptide) and V-263 (the start of the procollagen homology domain), inclusive, and ends between amino acid R-792 (the end of the third type 3 repeat) and Y-982 (the third of the predicted chymotrypsin cleavage sites in the C-terminal domain), inclusive. Preferably such a fragment starts between N-230 and G-253, inclusive, and ends between G-787 and V-811, inclusive, which is at or near a predicted chymotrypsin cleavage site, Y-799, in the fourth type 3 repeat; said portion being at least 3 amino acyl acids in length (preferably at least 4 amino acyl residues in length, more preferably at least 6 amino acyl residues). Protein molecular weights here were computed using standard computational aids (such aids are available, for example, at the web site of the Bioinformatics Organization, Inc., http://bioinformatics.org/sms/prot_mw.html; see Stothard, P. 2000. The sequence manipulation suite: JavaScript programs for analyzing and formatting protein and DNA sequences. BioTechniques 28: 1102-1104) and adjusted upwards to account for post-translational modifications. Predicted cleavage sites for chymotrypsin (and any closely related protease) were identified using tools available from the ExPASy (Expert Protein Analysis System) proteomics server of the Swiss Institute of Bioinformatics (SIB) (See http://us.expasy.org/cgi-bin/peptidecutter/peptidecutter.p1) and were limited to predicted sites of at least 80% probability. The uses of said fragments and portions include, but are not limited to, the induction and/or screening of an antibody and/or another binding agent of interest in a diagnostic method and use in a diagnostic assay. In particular embodiments, the invention is one of the specified fragments, rather than a portion thereof. In additional embodiments, a fragment and/or a portion can incorporate or be linked to a label and/or a carrier.
[0012] Throughout, wherever reference is made to a fragment or a portion thereof (or an immunoreactive portion thereof), it is understood that the fragment is a preferred embodiment of the invention. It is also understood throughout this Application that immunogenic portions, immunoreactive portions, and/or epitopes are generally six amino acyl residues long or longer, but an occasional portion or epitope can be shorter. Such shorter portions or epitopes are also contemplated.
[0013] Five additional aspects are:
[0014] 1) A purified and/or synthetic thrombospondin fragment, said fragment being at least 6 contiguous amino acyl residues in length, and wherein the fragment comprises a protease-resistant core domain or a part thereof, said domain or part thereof being selected from the group consisting of a domain of inter-chain disulfide bonds, an oligomerization domain, a procollagen-like domain, a type 1 repeat, a type 2 repeat, and a type 3 repeat, said part being at least 6 amino acyl residues in length.
[0015] 2) A purified and/or synthetic thrombospondin fragment, said fragment being at least 6 contiguous amino acyl residues in length, and wherein the fragment comprises an amino acid sequence selected from the group consisting of TEENKE (SEQ ID NO:1), CLQDSIRKVTEENKE (which includes an N-terminal Cys added to aid conjugation) (SEQ ID NO:2), LQDSIRKVTEENKE (SEQ ID NO:3), EGEARE (SEQ ID NO:4), PQMNGKPCEGEARE (SEQ ID NO:5), EDTDLD (SEQ ID NO:6), YAGNGIICGEDTDLD (SEQ ID NO:7), CNSPSPQMNGKPCEGEAR (SEQ ID NO:8), RKVTEENKELANELRRP (SEQ ID NO:9), CRKVTEENKELANELRRP (which includes an N-terminal Cys added to aid conjugation) (SEQ ID NO:10), PQMNGKPCEGEAR (SEQ ID NO:11), CEGEAR (SEQ ID NO:12), and RKVTEENKE (SEQ ID NO:13). (In particular embodiments the fragment comprises two, or even all of the foregoing sequences).
[0016] 3) a purified and/or synthetic thrombospondin fragment, said fragment being at least 6 contiguous amino acyl residues in length, and wherein the fragment comprises a collagen type V binding domain or a portion thereof.
[0017] 4) A purified and/or synthetic thrombospondin fragment, said fragment being at least 6 contiguous amino acyl residues in length, and wherein the fragment comprises an epitope for binding at least one of the following commercially available antibodies, each of which recognizes a ˜450 kDa (non-reduced) protein that is specifically identified as thrombospondin (the TSP Ab numbering, e.g., “TSP Ab-2”, comes from Lab Vision Corporation, Fremont, Calif., which currently has a web site at http://www.labvision.com/; clone designations refer to the hybridoma clone that produces a particular monoclonal antibody) It is also understood that said fragment includes a fragment that can be designed to bind a pre-existing monoclonal antibody, through the use of peptide scanning analysis, competition experiments, and other methods known in the art (for an example of such methods, see Corada M et al. Monoclonal antibodies directed to different regions of vascular endothelial cadherin extracellular domain affect adhesion and clustering of the protein and modulate endothelial permeability. Blood. 2001 Mar. 15; 97(6):1679-84). It is also understood that the current invention includes, but is not limited to, uses of pre-existing antibodies independent of a purified and/or synthetic fragment, some of which uses are also listed below.
TSP Ab-2 (Clone D4.6): This antibody is stated to react against reduced and non-reduced protein, and its epitope is in the calcium-binding domain of TSP (C-terminal 50-kDa piece of the 120-kDa fragment from protease digestion of Ca-replete TSP). The calcium-binding region is generally considered to be in the type 3 repeats (TSP residues 698-925). For example, it is expected that TSP Ab-2 will bind thrombospondin but not the 30-kDa circulating fragment. This antibody can be used to detect and/or quantify TSP and/or a circulating fragment; distinguish thrombospondin from a circulating fragment; and/or distinguish one or more fragments from each other. It shows no cross-reaction with fibronectin, fibrinogen, and von Willebrand factor. Its binding to thrombospondin is enhanced by EDTA i.e. at low [Ca2+].
[0019] TSP Ab-4 (Clone A6.1): This antibody is stated to react against reduced and non-reduced protein, and its epitope is in the collagen type V-binding domain. This antibody binds thrombospondin, and the applicant has discovered that it binds the three major TSP fragments in human plasma. Thus, this antibody can be used to detect and/or quantify TSP and/or a circulating fragment or fragments. In combination with another antibody or binding agent, it can be used in an assay to distinguish thrombospondin from a circulating fragment; and/or to distinguish one or more fragments from each other. As an example meant to be illustrative and not restrictive, TSP Ab-4 is used to capture TSP and circulating fragments, and then the other antibody or binding agent is used for detection, but is able to distinguish TSP from a fragment or fragments, or one fragment from another. It is understood that TSP Ab-4 also binds thrombospondin and thrombospondin fragments from important non-human sources as well, including but not limited to the dog. Thus, the use of this antibody and/or a similar binding agent in an assay for a thrombospondin fragment or fragments in a sample from a non-human source, such as dog, is contemplated. This antibody shows no cross-reaction with fibronectin, fibrinogen, and von Willebrand factor. This antibody inhibits thrombospondin-collagen interaction, and its binding to thrombospondin is unaffected by glycosaminoglycans (e.g. hyaluronic acid, chondroitin sulfate, and heparin). Also, its binding is enhanced by EDTA i.e. at low conc. of Ca2+.
TSP Ab-5 (Clone B5.2): This antibody is stated to react against reduced and non-reduced protein, and its epitope is in a 10-kDa fragment present at the junction of type 2 and type 3 repeats. The junctional region is listed elsewhere as residues 674-697, but this is only 24 residues and less than 10-kDa, so the epitope is less precisely mapped. It is expected that this antibody will bind TSP but not the 30-kDa circulating fragment. Thus, this antibody can be used to detect and/or quantify TSP and/or a circulating fragment or fragments; distinguish thrombospondin from a circulating fragment; and/or distinguish one or more fragments from each other. It shows no cross-reaction with fibronectin, fibrinogen, and von Willebrand factor. TSP Ab-9 (Clone MBC 200.1): This antibody is stated to react against reduced and non-reduced protein, and its epitope is in the N-terminal heparin-binding domain of thrombospondin. Thus, it should bind to thrombospondin but not to major circulating fragments. In Western blotting, Ab-9 reacts with a 25 kDa peptide (heparin-binding domain) from thermolysin digests of thrombospondin that is not disulfide bonded to any other region of the thrombospondin molecule. Heparin efficiently inhibits the binding of Ab-9 to thrombospondin. Thus, this antibody can be used to detect and/or quantify TSP; and/or distinguish thrombospondin from a circulating fragment or fragments. This antibody is not suitable for detecting all major fragments in the circulation. TSP Ab-8 (rabbit polyclonal antibody): Recognizes a ˜450 kDa (non-reduced) or 180 kDa (reduced) protein, identified as TSP. This antibody, which is a rabbit polyclonal, can be used in sandwich ELISAs for capture or detection and in competitive ELISAs. The applicant has discovered that it binds the three major TSP fragments in human plasma. Thus, this antibody can be used to detect and/or quantify TSP and/or a circulating fragment or fragments. In combination with another antibody or binding agent, it can be used in an assay to distinguish thrombospondin from a circulating fragment; and/or to distinguish one or more fragments from each other.
[0023] As an example meant to be illustrative and not restrictive, one takes the difference between (a) the result of an assay using an antibody or binding agent that binds TSP and the major circulating fragments in plasma, versus (b) the result of an assay using an antibody or binding agent that binds TSP but not major fragments. The antibody or binding agent in (a) is selected from the group consisting of TSP Ab-4, TSP Ab-8, TSP Ab-11, and an antibody or binding agent that binds TSP and the major circulating fragments in plasma. The antibody or binding agent in (b) is selected from the group consisting of TSP Ab-3, TSP Ab-6, TSP Ab-9, and an antibody or binding agent that binds TSP but none of the major circulating fragments. Said assay in (a) detects TSP plus fragments; said assay in (b) detects TSP; said difference, (a) minus (b), thereby gives a quantification of fragments without TSP. Likewise, differences can be taken between (c) the result of an assay using an antibody or binding agent that binds TSP and a subset of the major circulating fragments in plasma, versus the result of (a), above, to obtain a quantification of the fragment or fragments not detected in (c). Differences can also be taken of the result of (c) versus (b), above, to obtain a quantification of the fragment or fragments detected in (c) but without the signal from TSP. The antibody or binding agent in (c) is selected from the group consisting of TSP Ab-2, TSP Ab-5, TSP Ab-1, TSP Ab-7, and an antibody or binding agent that binds TSP and only a subset of the major circulating fragments.
TSP Ab-11 (Clones D4.6+A6.1+MBC 200.1): The Ab-11 cocktail is designed for sensitive detection of thrombospondin by Western blotting. This antibody cocktail shows no cross-reaction with fibronectin, fibrinogen, and von Willebrand factor. Because it is a mixture of TSP Ab-2, TSP Ab-4, and TSP Ab-9, it detects TSP and the three major TSP fragments in human plasma. Thus, this antibody can be used to detect and/or quantify TSP and/or a circulating fragment or fragments. In combination with another antibody or binding agent, it can be used in an assay to distinguish thrombospondin from a circulating fragment; and/or to distinguish one or more fragments from each other. It can also be used in an assay for TSP and/or a TSP fragment or fragments in a sample from a non-human source, such as a dog.
[0025] Other antibodies that are useful, even though they have been disclosed only as binding non-reduced protein include, but are not limited to TSP Ab-1, TSP Ab-3, TSP Ab-6, and TSP Ab-7, which are described in more detail immediately below:
TSP Ab-1 (Clone A4.1): This antibody is stated to bind the N-terminal half of the central stalk-like region of thrombospondin. This region is recovered as a 50 kDa fragment after chymotryptic digestion of thrombospondin. Thus, Ab-1 may be used to detect and/or quantify TSP and/or a circulating fragment or fragments; distinguish thrombospondin from a circulating fragment or fragments; and/or distinguish one or more fragments from each other. TSP Ab-1 shows no cross-reaction with fibronectin, fibrinogen, and von Willebrand factor. It inhibits the adhesion of human melanoma G361 cells, keratinocytes, squamous carcinoma cells, and rat smooth muscle cells to thrombospondin. It does not inhibit aggregation of thrombin-induced platelets. This antibody is stated to block the anti-angiogenic activity of thrombospondin by inhibiting its binding to TSP-Receptor/CD36. TSP Ab-3 (Clone C6.7): This antibody is stated to bind the platelet or cell-binding domain at the extreme C-terminus of TSP and should therefore distinguish TSP from fragments. Thus, this antibody can be used to detect and/or quantify TSP; and/or distinguish thrombospondin from a circulating fragment or fragments. This antibody is not suitable for detecting the three major fragments in the circulation. Heparin or EDTA may marginally affect binding of Ab-3 to thrombospondin. Ab-3 blocks thrombospondin-mediated agglutination of fixed red blood cells. It shows no effect on thrombospondin-mediated agglutination of fixed, activated platelets. It inhibits both thrombin- and A23187-induced aggregation of washed, live (not fixed) platelets without affecting the secretion of serotonin. Ab-3 inhibits adhesion of melanoma G361 cells to thrombospondin, and blocks the binding of C-terminal domain to Integrin-Associated Protein (IAP)/CD47. TSP Ab-6 (Clone A2.5): This antibody has been shown to immunoprecipitate thrombospondin. This antibody shows no cross-reaction with fibronectin, fibrinogen, and von Willebrand factor. Its epitope localizes in the heparin-binding domain of thrombospondin, and therefore, heparin efficiently inhibits the binding of Ab-6 to thrombospondin. Thus, this antibody can be used to detect and/or quantify TSP; and/or distinguish thrombospondin from a circulating fragment or fragments. This antibody is not suitable for detecting the three major fragments in the circulation. Hyaluronic acid and chondroitin sulfate show no inhibition at low concentration and only partially inhibit over the concentration range at which heparin abolishes the binding. Thrombospondin binds with high affinity to a sulfated glycolipid or sulfatide found on red cell and platelet membranes. Ab-6 blocks the binding of thrombospondin to sulfatides at low concentrations. Ab-6 immunoprecipitates a 25 kDa peptide (heparin-binding domain) from chymotryptic digests of thrombospondin that is not disulfide bonded to any other region of the thrombospondin molecule. This antibody inhibits the hemagglutination of trypsinized, glutaraldehyde-fixed human erythrocytes by purified thrombospondin. It also inhibits the agglutination of fixed, activated platelets by thrombospondin. It does not inhibit either thrombin- or A23187-induced aggregation of washed, live platelets. Ab-6 does not bind to reduced and alkylated thrombospondin or thrombospondin transferred to nitrocellulose membrane after SDS-PAGE. TSP Ab-7 (Clone HB8432): This antibody is stated to bind type 2 repeats. Thus, Ab-7 may be used to detect and/or quantify TSP and/or a circulating fragment or fragments; distinguish thrombospondin from a circulating fragment or fragments; and/or distinguish one or more fragments from each other. It shows no cross-reaction with fibronectin or any other serum or platelet proteins except thrombospondin. Its epitope localizes in the EGF-like repeats (type 2) in the stalk region of human thrombospondin (disulfide-bonded core remaining after trypsin digestion).
[0030] All of the antibodies listed above can be purchased from Lab Vision Corporation, Fremont, Calif. currently with a web site at http://www.labvision.com/. See also the published literature such as, for TSP Ab-4, Galvin N.J. et al. Interaction of human thrombospondin with types I-V collagen: direct binding and electron microscopy. J Cell Biol. 1987 May; 104(5):1413-22). It is also understood that alternative antibodies may also be generated against any of the abovementioned epitopes.
[0031] 5) A purified and/or synthetic thrombospondin fragment, said fragment being at least 6 contiguous amino acyl residues in length, and wherein the fragment does not comprise at least one fibrinogen-binding region selected from the group consisting of (1) a fibrinogen-binding domain within a 210-kDa fragment of TSP, where said 210-kDa fragment is composed of three 70-kDa fragments that contain the region of interchain disulfide bonds, the procollagen homology region, and the type 1 and type 2 repeats, (2) a fibrinogen-binding region in the amino-terminal domain of thrombospondin, (3) a fibrinogen-binding region in an 18-kDa amino-terminal heparin-binding domain of thrombospondin, and (4) a region corresponding to synthetic peptide N12/I encompassing amino acid residues 151-164 (I-151 to P-164) of the N-terminal domain of thrombospondin-1. In a particular embodiment, the fragment does not comprise any of the fibrinogen-binding regions in the group.
[0032] For each of the 5 additional aspects, the molecular weight of the thrombospondin fragment does not exceed 110 kDa; alternatively does not exceed 55 kDa; or alternatively does not exceed 35 kDa, wherein the size in kDa is that determined by gel electrophoresis after disulfide bond reduction. The fragments of the 5 additional aspects of the invention can be used to induce antibodies (and/or other binding molecules) of interest in the diagnostic methods or can be used in diagnostic assays, for example, as calibrators, indicators, and/or competitors. It is understood that a fragment can be derivatized, for example, to incorporate and/or be coupled to a label and/or a carrier.
[0033] A fragment that can be as little as 6 amino acyl residues in length is preferably immunoreactive. A typical method for immunizations comprises coupling the peptide to a carrier, such as keyhole limpet hemocyanin or ovalbumin. Said couplings to a carrier are also contemplated in the current invention.
[0034] The inclusion of the central protease-resistant core domain in the definition of the fragments follows from considerations discussed elsewhere herein. This domain is considered to comprise locations in the mature thrombospondin protein selected from the group consisting of: a domain of interchain disulfide bonds (around Cys-252 and Cys-256, preferably residues 241-262); the procollagen homology domain (residues 263-360); the type 1 repeats (residues 361-530); the type 2 repeats (residues 531-673); there is a short segment (residues 674-697) between the type 2 repeat doman and the type 3 repeat domain; and then the type 3 repeats (residues 698-925); see FIG. 1 of this Application for examples of protease-resistant fragments that have been reported after artificial digestions in vitro; Chapter 2, “The primary structure of the thrombospondins” in in The Thrombospondin Gene Family by J C Adams, R P Tucker, & J Lawler, Springer-Verlag: New York, 1995, pp. 11-42, particularly p. 12; and Chapter 6, “Mechanistic and functional aspects of the interactions of thrombospondins with cell surfaces,” ibidem, pp. 105-157, particularly p. 115. Interchain disulfide bonds (in the region of residues 241-262) are often preserved in protease-resistant fragments. The term “mature”, as used here to refer to the mature thrombospondin protein sequence, means without the 18- to 22-residue signal peptide sequence, here assumed to be 18 residues, following The Thrombospondin Gene Family by J C Adams et al. 1995; see the full human thrombospondin sequence given below in this text; see also FIG. 1 of this application, and the discussions thereof. Nevertheless, it is understood that GenBank file NM — 003246.1, also listed as GI:4507484, currently identifies nucleotide residues “112 . . . 204” as encoding the signal peptide, which implies a signal peptide of 31 amino acyl residues).
[0035] The identification of these peptides, TEENKE (SEQ ID NO:1), LQDSIRKVTEENKE (SEQ ID NO:3), EGEARE (SEQ ID NO:4), PQMNGKPCEGEARE (SEQ ID NO:5), EDTDLD (SEQ ID NO:6), YAGNGIICGEDTDLD (SEQ ID NO:7), CNSPSPQMNGKPCEGEAR (SEQ ID NO:8), RKVTEENKELANELRRP (SEQ ID NO:9), PQMNGKPCEGEAR (SEQ ID NO:11), CEGEAR (SEQ ID NO:12), and RKVTEENKE (SEQ ID NO:13) was achieved by computerized surveys of thrombospondin, the surveys done by request at commercial sources to identify immunogenic regions (epitopes), but these surveys identified many peptides with immunogenic regions, and so the surveys were followed by selection of relevant peptides and/or epitopes based on knowledge of circulating thrombospondin fragments. Other peptides and/or epitopes listed in this application were similarly identified.
[0036] A criterion that a fragment comprises an immunogenic and/or immunoreactive portion from a collagen type V binding domain follows from the published properties (e.g., Galvin N.J. et al. Interaction of human thrombospondin with types I-V collagen: direct binding and electron microscopy. J Cell Biol. 1987 May; 104(5):1413-22) of the commercially available TSP Ab-4 antibody used below to detect thrombospondin fragments of interest in the plasma.
[0037] The collagen V-binding domain of thrombospondin has been mapped to the amino acid sequence corresponding to the region between valine(333) and lysine(412) (V-333 to K-412, using the single-letter symbols V and K for their respective amino acids), inclusive, of human thrombospondin-1 (Takagi T et al. A single chain 19-kDa fragment from bovine thrombospondin binds to type V collagen and heparin. J Biol Chem 268:15544-15549, 1993; as mentioned above, numbers here refer to the mature thrombospondin protein, that is, without the 18- to 22-residue signal peptide sequence, here assumed to be 18 residues). This region would include a portion of the procollagen homology region of thrombospondin and all or nearly all of the first type 1 repeat of thrombospondin (see Chapter 2, “The primary structure of the thrombospondins” in The Thrombospondin Gene Family by J C Adams, R P Tucker, & J Lawler, Springer-Verlag: New York, 1995, pp. 11-42, but especially p. 24).
[0038] The criterion that the fragment comprise an epitope for binding the commercially available TSP Ab-4 antibody follows from the fact that the TSP Ab-4 antibody was used below to successfully detect thrombospondin fragments of interest in the plasma, including the plasma of cancer patients. Significantly, this TSP Ab-4 antibody is described as binding the collagen type V binding domain of thrombospondin.
[0039] For references regarding a fibrinogen-binding region within a 210-kDa fragment of TSP composed of three 70-kDa fragments that contain the region of interchain disulfide bonds, the procollagen homology region, and the type 1 and type 2 repeats, see p. 24 of Adams et al. The Thrombospondin Gene Family; citation 53 therein, which is Lawler J et al. Thrombin and chymotrypsin interactions with thrombospondin. Ann NY Acad Sci. 1986; 485:273-87; and citations immediately below. Additional references for the fibrinogen-binding regions to be excluded include: for a region in an 18-kDa amino-terminal heparin-binding domain of thrombospondin (so-called TSP 18), see Bonnefoy A et al.: A model of platelet aggregation involving multiple interactions of thrombospondin-1, fibrinogen, and GPIIbIIIa receptor. J Biol Chem. 2001 Feb. 23; 276(8):5605-12. For a region corresponding to synthetic peptide N12/I encompassing amino acid residues 151-164 of the N-terminal domain of thrombospondin-1, see Voland C et al.: Platelet-osteosarcoma cell interaction is mediated through a specific fibrinogen-binding sequence located within the N-terminal domain of thrombospondin 1. J Bone Miner Res. 2000 February; 15(2):361-368. Citations for two fibrinogen-binding domains include p. 24 of Adams et al. The Thrombospondin Gene Family (and citations 51-54 therein), and for the role of the type 1 repeats include Panetti T S et al.: Interaction of recombinant procollagen and properdin modules of thrombospondin-1 with heparin and fibrinogen/fibrin. J Biol Chem. 1999 Jan. 1; 274(1):430-7.
[0040] Thrombospondin is a glycosylated protein. Therefore, depending on which portion of thrombospondin is considered, the thrombospondin fragments of the invention may be glycosylated or non-glycosylated. Potential sites for N-linked carbohydrate chains include N-230 (in the N-terminal domain), N-342 (in the procollagen homology domain), N-503 (in the type 1 repeat domain), N-690 (in the region between the type 2 and type 3 repeat domains), N-1033 (in the C-terminal domain), and N-1049 (in the C-terminal domain). It is also understood that specific C- and O-linked saccharide attachments occur, particularly in the type 1 repeat domain (see Hofsteenge J, Huwiler K G, Macek B, Hess D, Lawler J, Mosher D F, Peter-Katalinic J: C-mannosylation and O-fucosylation of the thrombospondin type 1 module. J Biol Chem. 2001 Mar. 2; 276(9):6485-6498). It is also understood that β-hydroxylation of thrombospondin can occur (such as at N-592, which is in the type 2 repeat domain; see FIG. 2.2a in Adams J C et al. The Thrombospondin Gene Family, 1995, p. 16), and that any of these modifications can be incorporated, or not, into thrombospondin fragments and/or peptides of the current invention.
[0041] Nonglycosylated entities of particular interest are synthetic peptides.
[0042] In particular embodiments, the thrombospondin fragments of the invention are derivatized so that they comprise and/or are linked to a detectable label and/or a carrier. In particular embodiments, the label is selected from the group consisting of a radioactive label, a fluorescent label, a chemical label, a colorometric label, an enzymatic label, a non-fluorescent label, a non-radioactive label, a biotin moiety, and an avidin moiety. In particular embodiments, the carrier is selected from the group consisting of a bead, a microsphere, a coded microsphere, a solid matrix, a keyhole limpet hemocyanin, an albumin, linkage to a cross-linking agent, an epitope tag, and an epitope.
[0043] It is understood that a synthetic or purified thrombospondin fragment of the invention retains its identity as a fragment of the invention even if it has been derivatized by the addition of additional material, such as detectable label, or through conjugation to another molecule, or by synthesizing it as part of a chimeric protein, to name just three of many possible examples.
Binding Agents
[0044] The detection of either thrombospondin fragments or thrombospondin usually requires the use of agents that will bind to them. Such agents may be multi-chain antibodies, single-chain antibodies, proteins that are not antibodies, non-protein molecules, or derivatives or combinations thereof. Polyclonal and monoclonal antibodies are normally immunoglobulins, i.e., multi-chain antibodies. In the case of immunoglobulin-G (IgG), each antibody molecule consists of a pair of heavy chains and a pair of light chains. The multichain antibodies are typically from mammalian or avian sources. Single-chain antibodies and non-antbodies are discussed below.
[0045] The term “antibodies” by itself, when not specified as being a single-chain antibodies, refers to 4-chain antibodies, those with two heavy and two light polypeptide chains. By way of example, this includes but is not limited to the IgG classes of antibodies, but also other classes, such as ones that occur in higher multimers, such as IgM. IgA and IgY are also contemplated.
[0046] The term “protein” is intended to include not only molecules normally referred to as proteins but also those that may be referred to as polypeptides.
[0000] Methods of Detecting the Thrombospondin Fragments while Distinguishing, or not Distinguishing, from Thrombospondin Itself
[0047] In one such an aspect, the invention includes an assay to detect a thrombospondin fragment of the invention wherein the assay distinguishes the thrombospondin fragment from thrombospondin itself. The thrombospondin fragments of particular interest are ones found in humans and are within a range selected from the group consisting of 80 to 100 kDa, 40 to 55 kDa and 20 to 30 kDa, wherein the size in kDa is that determined by gel electrophoresis after disulfide bond reduction Most preferably they are selected from the group consisting of an ˜85 kDa to 90 kDa fragment, an ˜50 kDa fragment, and an ˜30 kDa fragment. The assay may detect just one such fragment, or a combination of 2 or more.
[0048] In cases where the concentration of higher molecular weight forms, including thrombospondin itself, is low in a sample (such as in the samples shown in FIGS. 3 and 4 , Results of Western Blot analysis using TSP Ab-4 antibody), detection of fragments without necessarily excluding thrombospondin is an approach also contemplated by the current invention. Low concentrations of thrombospondin can be achieved in many cases by preventing or reducing platelet activation during sample collection and/or storage (see below for contemplated methods). This aspect of the current invention comprises several advantages over conventional detection methods that have used binding agents against the entire thrombospondin molecule (and these binding agents have been limited to antibodies). Said advantages include but are not limited to the use of binding agents that are directed specifically against the fragments of interest and not portions of the thrombospondin molecule outside of these fragments, the use of relevant peptides and/or thrombospondin fragments to generate said binding agents (such as antibodies), the use of relevant peptides and/or thrombospondin fragments as assay calibrators, and the use of relevant peptides and/or thrombospondin fragments as assay indicators.
[0049] Any of several acceptable approaches can be used for the assay of a thrombospondin fragment (or fragments) wherein the assay distinguishes it from thrombospondin, and more than one of these can be used in a given assay. In one approach, the assay comprises a step wherein the fragment is physically separated from the thrombospondin. Generally that approach is combined with a step in which the presence of the fragment or thrombospondin is shown by their reaction with a specific binding agent. In particular embodiments, the physical separation technique is selected from the group consisting of gel electrophoresis, dialysis, chromatography, size chromatography, affinity chromatography, immunoaffinity chromatography, adsorption, immunoadsorption, isoelectric focusing, mass spectrometry, centrifugation, sedimentation, floatation, precipitation, immunoprecipitation, and gel filtration.
[0050] In a second approach, the assay distinguishes the fragment (or fragments) based on one or more epitopes (here “epitope” meaning a target to which a binding agent, i.e., an antibody or a non-antibody, binds) in the fragment that are not present in thrombospondin, including but not limited to an epitope at an end of a fragment and an epitope that is displayed by a fragment but is shielded in thrombospondin.
[0051] In a third approach, the assay distinguishes the fragment (or fragments) based on one or more epitopes in thrombospondin that are not present in the fragment. As an illustrative but not restrictive example, an epitope shared by thrombospondin and a thrombospondin fragment is used to obtain a quantitation of a total, thrombospondin plus thrombospondin fragment(s), from which is then subtracted a quantitation of thrombospondin obtained using an epitope present in thrombospondin but not present in a fragment. The difference between the two quantitations is a quantitation of the amount of fragment As an example, epitopes in thrombospondin but not in at least one fragment from the group of an 80 to 100 kDa, a 40 to 55 kDa, or a 20 to 35 kDa fragment present in plasma can be selected from the group consisting of an epitope from outside the protease-resistant central core domain, an epitope in the N-terminal domain, an epitope in the N-terminal heparin-binding domain, a heparin-binding sequence in the N-terminal domain, a heparin-binding sequence in the N-terminal domain selected from the group consisting of residues 23-32 (RKGSGRRLVK), residues 23-29 (RKGSGRR), and residues 77-83 (RQMKKTR) of the mature protein (see Chapter 2, “The primary structure of the thrombospondins” in The Thrombospondin Gene Family by J C Adams, R P Tucker, & J Lawler, Springer-Verlag: New York, 1995, pp. 11-42, but especially p. 13 & Table 2.1; Chapter 6, “Mechanistic and functional aspects of the interactions of thrombospondins with cell surfaces,” ibidem pp. 105-157, but especially pp. 108 & 114; Lawler J et al. Expression and mutagenesis of thrombospondin. Biochemistry. 1992 Feb. 4; 31(4):1173-80; and Cardin A D & Weintraub H J. Molecular modeling of protein-glycosaminoglycan interactions. Arteriosclerosis. 1989 January-February; 9(1):21-32), a heparin-binding sequence in the N-terminal domain selected from the group consisting of residues 22-29 (ARKGSGRR), residues 79-84 (MKKTRG), and residues 178-189 (RLRIAKGGVNDN) of the mature protein (reviewed in the Discussion section of Voland C et al.: Platelet-osteosarcoma cell interaction is mediated through a specific fibrinogen-binding sequence located within the N-terminal domain of thrombospondin 1. J Bone Miner Res. 2000 February; 15(2):361-368), an epitope in the C-terminal domain, an epitope in the C-terminal cell-binding domain, a thrombospondin epitope not found in a plasma fragment, a thrombospondin epitope not found in a plasma fragment of 80 to 100 kDa, a thrombospondin epitope not found in a plasma fragment of 40 to 55 kDa, and a thrombospondin epitope not found in a plasma fragment of 20 to 35 kDa, where all kDa molecular weights are those after reduction. It is understood that the absence of a strong, functional heparin-binding domain from a thrombospondin fragment in plasma will be a factor allowing its accumulation in plasma (many heparin- or heparan-binding proteins are cleared from plasma very quickly; see for example, Wallinder L et al. Rapid removal to the liver of intravenously injected lipoprotein lipase. Biochim Biophys Acta. 1979 Oct. 26; 575(1):166-73).
[0052] The epitopes may be divided into three Groups. Group 1: An epitope shared by thrombospondin and a thrombospondin fragment present in plasma is preferably one that is contained within an amino acid sequence selected from the group consisting of TEENKE (SEQ ID NO:1), CLQDSIRKVTEENKE (which includes an N-terminal Cys added to aid conjugation) (SEQ ID NO:2), LQDSIRKVTEENKE (SEQ ID NO:3), EGEARE (SEQ ID NO:4), PQMNGKPCEGEARE (SEQ ID NO:5), EDTDLD (SEQ ID NO:6), YAGNGIICGEDTDLD (SEQ ID NO:7), CNSPSPQMNGKPCEGEAR (SEQ ID NO:8), RKVTEENKELANELRRP (SEQ ID NO:9), CRKVTEENKELANELRRP (SEQ ID NO: 10), PQMNGKPCEGEAR (SEQ ID NO:11), CEGEAR (SEQ ID NO:12), RKVTEENKE (SEQ ID NO:13), or a portion at least 3 amino acyl residues in length (preferably at least 4 amino acyl residues in length, more preferably at least 6 amino acyl residues) of such an amino acid sequence.
[0053] Group 2: An epitope in thrombospondin but not in an 80 to 100 kDa, 40 to 55 kDa, and/or 20 to 35 kDa fragment present in plasma is preferably one contained within an amino acid sequence selected from the group consisting of TERDDD (SEQ ID NO: 24), DFSGTFFINTERDDD (SEQ ID NO: 25), ERKDHS (SEQ ID NO: 26), TRGTLLALERKDHS (SEQ ID NO: 27), CTRGTLLALERKDHS (SEQ ID NO: 28) (which includes an N-terminal Cys added to aid conjugation), DDKFQD (SEQ ID NO: 29), ANLIPPVPDDKFQD (SEQ ID NO: 30), CANLIPPVPDDKFQD (SEQ ID NO: 31) (which includes an N-terminal Cys added to aid conjugation), DCEKME (SEQ ID NO: 32), EDRAQLYIDCEKMEN (SEQ ID NO: 33) (although it is understood that this sequence and its fragments impinge on the sequence of the fibrinogen-binding N12/I peptide), CGTNRIPESGGDNSVFD (SEQ ID NO: 34), NRIPESGGDNSVFD (SEQ ID NO: 35), GWKDFTAYRWRLSHRPKTG (SEQ ID NO: 36), CGWKDFTAYRWRLSHRPKTG (SEQ ID NO: 37) (which includes an N-terminal Cys added to aid conjugation), or a portion at least 3 amino acyl residues in length (preferably at least 4 amino acyl residues in length, more preferably at least 6 amino acyl residues) of such an amino acid sequence.
[0054] Various modifications, such as a C-terminal Cys, can be added to a peptide of interest to allow easier conjugation to a carrier protein such as KLH, ovalbumin, and others. This is particularly true for the following peptides: RKVTEENKELANELRRP (SEQ ID NO: 9), LQDSIRKVTEENKE (SEQ ID NO: 3); TRGTLLALERKDHS (SEQ ID NO: 27), and ANLIPPVPDDKFQD (SEQ ID NO: 30), and these modifications provide alternative conjugation strategies for NRIPESGGDNSVFD (SEQ ID NO: 35) and others.
[0055] In approaches related to the above, the assay can distinguish fragments from each other, based on physical separation methods and/or on shared and/or non-shared binding agent targets. Thus, for example, size-exclusion chromatography and/or SDS-polyacrylamide gel electrophoresis can be used to separate the ˜85 to 90, ˜50-, and ˜30-kDa fragments from each other, for separate quantitation (an example of this is shown in FIG. 3 , with the quantitation presented in Table 2). Also, for example, an epitope (meaning a binding agent target) in the ˜85 to 90-kDa fragment that is not contained in the ˜50- and/or the ˜30-kDa fragments can be used to assay it separately, and/or can be used to subtract its contribution from a total to obtain results reflective of the smaller fragments.
[0056] Group 3: An additional epitope, useful as a binding agent target for distinguishing a fragment from full-length TSP, and/or distinguishing two fragments of different sizes is preferably one contained within an amino acid sequence selected from the group consisting of DDDDNDKIPDDRDNC (SEQ ID NO: 14), DDDDNDKIPDDRDNC[NH2] (SEQ ID NO: 15), DDDDNDK (SEQ ID NO: 16), NLPNSGQEDYDKDG (SEQ ID NO: 17), CNLPNSGQEDYDKDG (SEQ ID NO: 18), EDYDKD (SEQ ID NO: 19), CPYNHNPDQADTDNNGEGD (SEQ ID NO: 20), CRLVPNPDQKDSDGD (SEQ ID NO: 21), DQKDSDGD (SEQ ID NO: 22), CPYVPNANQADHDKDGKGDA (SEQ ID NO: 23), or a portion at least 3 amino acyl residues in length (preferably at least 4 amino acyl residues in length, more preferably at least 6 amino acyl residues) of such an amino acid sequence.
[0057] It is also understood that some peptides that contain an epitope shared by thrombospondin and a first thrombospondin fragment present in plasma may contain an epitope that is not shared by a second thrombospondin fragment present in plasma. Said peptides are useful in many applications described herein, including but not limited to distinguishing thrombospondin from said second thrombospondin fragment, distinguishing said first from said second thrombospondin fragment, detecting and/or quantitating thrombospondin, detecting and/or quantitating said first thrombospondin fragment, detecting and/or quantitating said second thrombospondin fragment (in a combination assay described elsewhere herein), and producing a binding agent. Said peptides, which form a subset of Group 1, can be selected from the group consisting of EGEARE (SEQ ID NO: 4), PQMNGKPCEGEARE (SEQ ID NO: 5), EDTDLD (SEQ ID NO: 6), YAGNGIICGEDTDLD (SEQ ID NO: 7), CNSPSPQMNGKPCEGEAR (SEQ ID NO: 8), PQMNGKPCEGEAR (SEQ ID NO: 11), CEGEAR (SEQ ID NO: 12), or a portion at least 3 amino acyl residues in length (preferably at least 4 amino acyl residues in length, more preferably at least 6 amino acyl residues) of such an amino acid sequence.
[0058] It is also understood that the current invention also includes antibody and non-antibody molecules that bind these peptides, other peptides of thrombospondin specified herein, fragments thereof, and peptides that contain fragments thereof; as well as assays using a reagent from this list. It is understood that an antibody or a non-antibody that distinguishes thrombospondin from a fragment, or one fragment from another, can be employed to affinity-purify thrombospondin or a fragment.
[0059] In embodiments of particular interest, a sample of material (liquid tissue, solid tissue, urine, perspiration, cerebrospinal fluid, a body fluid, blood or a blood component, or stool; most preferably blood plasma) is taken or gathered from an organism (either a human or a non-human, preferably a mammal or a bird in the case of non-humans) and is subject to the assay. The inventions disclosed herein not only apply to fragments of human thrombospondin, but also to fragments of non-human thrombospondin. For example, there is a need to detect the presence of or monitor the status of disease, such as a cancer, in livestock, racehorses, pets, and other economically and/or emotionally important animals. The current inventions meet these needs.
[0060] In one set of embodiments, the assay detects the presence of, or monitors the course of, diseases and conditions that can affect plasma levels of thrombospondin fragments. Such diseases include, but are not limited to, many that in the prior art were assumed to affect plasma levels of thrombospondin: a cancer, renal failure, renal disease, atopic dermatitis, vasculitis, acute vasculitis, renal allograft, allergic asthma, diabetes mellitus, myocardial infarction, liver disease, splenectomy, dermatomyositis, polyarteritis nodosa, systemic lupus erythematosus, lupus erythematosus, Kawasaki syndrome, non-specific vasculitis, juvenile rheumatoid arthritis, rheumatoid arthritis, vasculitis syndrome, Henoch-Schönlein purpura, thrombocytopenic purpura, purpura, an inflammatory condition, a condition associated with clotting, a condition associated with platelet activation, a condition associated with intravascular platelet activation, a condition associated with consumption of platelets, heparin-induced thrombocytopenia, disseminated intravascular coagulation, intravascular coagulation, extravascular coagulation, a condition associated with endothelial activation, a condition associated with production and/or release of thrombospondin and/or a thrombospondin fragment, urticaria, hives, angioedema, a drug reaction, an antibiotic reaction, an aspartame reaction, atopic dermatitis, eczema, hypersensitivity, scleroderma, conditions associated with plugging of vessels, a condition associated with a cryofibrinogen, a condition associated with a cryoglobulin, and a condition associated with an anti-cardiolipin antibody.
[0061] In embodiments of particular interest, the assay for thrombospondin fragments is done to detect the presence of, or monitor the status of, a cancer in a human and/or in a non-human animal. In additional embodiments of interest, the assay is done to measure the degree of platelet activation.
[0062] In measurements of plasma levels of the fragments, it is preferred that the plasma is obtained by a method that prevents or reduces platelet activation and/or activation of a component of the clotting cascade during sample collection and/or storage; and/or by a method that prevents or reduces cleavage of thrombospondin into fragments (or fragments into smaller fragments) during sample collection and/or storage. Platelet activation and/or activation of a component of the clotting cascade during sample collection and/or storage can result in the release of thrombospondin, but also activation of proteases (including but not limited to a protease of the clotting cascade) that can cleave thrombospondin and some thrombospondin fragments, thereby complicating the assay. To prevent or reduce platelet activation during sample collection and/or storage, the method may be one that does not comprise the use of a tournequet. Also to prevent or reduce platelet activation and/or activation of clotting during sample collection and/or storage, the method may, for example, comprise a step selected from the group consisting of: (1) use of a large-bore needle, (2) discarding of the initial portion of the collected blood, (3) use of a coated needle, (4) use of a coated tubing, (5) storage of sample between −1° C. and 5° C., and (6) separation of plasma within 30 minutes of sample collection. Also to prevent or reduce platelet activation and/or protease activity during sample collection and/or storage, the method may comprise the use of an agent the use of an agent selected from the group consisting of a platelet inhibitor, a protease inhibitor, a serine protease inhibitor, an enzyme inhibitor, an inhibitor of an enzyme that is divalent cation dependent, a heparin, a heparin fragment, a heparan, an anticoagulant, a COX inhibitor, an inhibitor of a cell-adhesion molecule, an inhibitor of a surface receptor, a glycoprotein inhibitor, an inhibitor of a glycoprotein IIb/IIIa receptor, a thrombin inhibitor, an inhibitor of degranulation, a chelator, a citrate compound, theophylline, adenosine, and dipyridamole (Diatube H vacutainers containing citrate, theophylline, adenosine, and dipyridamole are commercially available from Becton Dickinson; see Bergseth G et al. A novel enzyme immunoassay for plasma thrombospondin: comparison with beta-thromboglobulin as platelet activation marker in vitro and in vivo. Thromb. Res. 99:41-50, 2000). Devices that minimize platelet activation and/or protease activity in a sample are also contemplated and include, but are not limited to, a collection tube containing a cocktail of platelet and/or clotting inhibitors, a collection tube containing a protease inhibitor, a collection tube containing an inhibitor of a protease that is or is derived from a blood component, and a device that discards or allows the easy discarding of the initial portion of collected blood. These methods can also be applied to samples of other body fluids.
[0063] A related aspect of the invention is a combination diagnostic test (especially for cancer) comprising at least two types of diagnostic tests, one of said tests being the assay for a thrombospondin fragment (or fragments) or a portion (or portions) thereof in plasma, the other assay not being based on a thrombospondin fragment or portion. In one set of embodiments, the test not based on a thrombospondin fragment or portion thereof is selected from the group consisting of an imaging test, a radiographic test, a nuclear medicine test, a magnetic resonance imaging test, a blood test, a biopsy, a genetic test, a guaiac test, a test for fecal occult blood, and a test for fecal blood, a cancer test not based on a thrombospondin fragment or portion thereof, a disease test not based on a thrombospondin fragment or portion thereof, and an endoscopy. In particular embodiments of the foregoing methods, a thrombospondin fragment comprises a detectable label (at least during some part of the method).
[0064] Detection can, for example, be part of a screening process. Such a screening could include a comparison against a reference value, involve a comparison against a previous value from the same individual; and/or be done repeatedly and/or periodically (e.g., once a year, once every six months, or once every 2, 3, 4, 5 or 10 years.). It is understood that screening can be performed on humans and/or on non-human animals
[0065] The foregoing methods are assays to detect a thrombospondin fragment of the invention wherein the assay distinguishes, or does not distinguish, a thrombospondin fragment from thrombospondin, or one thrombospondin fragment from another thrombospondin fragment. In any case, such fragments can be referred to as “target” fragments for purposes of the assay. In many instances it is desirable to have the method also comprise a calibration step or procedure, in which known amounts of a thrombospondin fragment (such as a peptide) are subjected to the method. Such “calibration” fragments are optionally detectably labeled. It is possible to perform the assays in which the target and calibration fragments comprise different detectable labels (or where one is detectably labeled and the other is not).
[0066] It is understood that interference resulting from fibrinogen binding to an N-terminal domain of thrombospondin is unlikely to affect the detection of thrombospondin fragments related to the protease-resistant core domain (which lack the N-terminal domain). Nevertheless, assays of thrombospondin could be affected (thus, avoiding that region of the N-terminus when assaying thrombospondin and/or diluting, removing, inhibiting, and/or otherwise compensating for interfering molecules is contemplated).
[0067] Additional potentially interfering substances, inferred from reports that these molecules are present in plasma and that they bind TSP, are plasminogen, histidine rich proteins including histidine-rich glycoprotein, and fibronectin (See, for example, Walz D A et al., Semin Thromb Hemost. 13(3):317-025 (1987); Vanguri V K et al., Biochem J. 2000 Apr. 15; 347(Pt 2):469-73). For binding of histidine-rich glycoprotein, two regions of thrombospondin have been implicated: type 1 repeats (Simantov et al. J Clin Invest. 2001 Jan, 107(1):45-52) and a TSP heparin binding domain (Vanguri VK et al., 2000). The heparin-binding domain of thrombospondin is expected to be absent from the circulating fragments.
[0068] To compensate for interfering substances in assays for thrombospondin fragments, diluting, removing, inhibiting, and/or otherwise compensating for interfering molecules is contemplated. As an illustrative, but not limiting, example, the inclusion of an inhibitor of thrombospondin-fibrinogen interactions is contemplated. Such an inhibitor is selected from the group consisting of synthetic peptide N12/I encompassing amino acid residues 151-164 of the N-terminal domain of thrombospondin-1 (see Voland C et al.: Platelet-osteosarcoma cell interaction is mediated through a specific fibrinogen-binding sequence located within the N-terminal domain of thrombospondin 1. J Bone Miner Res. 2000 February; 15(2):361-8), and an antibody to the cyanogen bromide cleavage fragment composed of residues 241-476 of the carboxyl-terminal end of the alpha chain of fibrinogen (see Tuszynski G P et al.: The interaction of human platelet thrombospondin with fibrinogen. Thrombospondin purification and specificity of interaction. J Biol Chem. 1985 Oct. 5; 260(22):12240-5).
Single Chain Antibodies and Non-Antibodies
[0069] Raising conventional antibodies (also referred to herein simply as “antibodies” as opposed to “single chain antibodies”; and an example of a conventional antibody is IgG, which is composed of two heavy chains and two light chains) is merely one of a number of methods that are generally based on the approach of random, semi-random, directed, combinatorial, and/or other means for the generation of large numbers of diverse peptides and/or non-peptides, that is then followed by a selection procedure to identify within this large number those peptides and/or non-peptides that bind to a target and/or an epitope within a target. Selection can then be followed by methods for improving the peptides and/or non-peptides to achieve better affinity and/or specificity. These diverse peptides and/or non-peptides may be conventional multi-chain antibodies (polyclonal or monoclonal), single-chain antibodies, or non-antibodies, including but not limited to peptides, products of phage display, aptamers, DNA, RNA, or modified DNA or RNA. Also contemplated are thrombospondin receptors and/or binding proteins (such as a CSVTCG receptor, a CSVTCG binding molecule, CD36, angiocidin, 26S proteasome non-ATPase regulatory subunit 4, and/or anti-secretory factor).
[0070] A well-known procedure for generation of large numbers of diverse peptides is through phage display, which is then followed by selection and can be further refined through other techniques such as molecular evolution (see, for example, Flores-Flores, C. et al, Development of human antibody fragments directed towards synaptic acetylcholinesterase using a semi-synthetic phage display library. J Neural Transm Suppl. 2002; (62):165-179; Qian, M.D, et al, Anti GPVI human antibodies neutralizing collagen-induced platelet aggregation isolated from a recombinant phage. Human. Antibodies. 2002; 11(3):97-105). scFv constructs can be made by linking variable domains of heavy (VH) and light (VL) chains together via a polypeptide linker (for example, see Asvadi P et al. Expression and functional analysis of recombinant scFv and diabody fragments with specificity for human RhD. J Mol Recognit 15:321-330, 2002). Peptides generated then selected (and then possibly improved) via this approach have been used in ELISAs and ELISA-like assays of their targets (e.g., see Schlattner U et al. Isoenzyme-directed selection and characterization of anti-creatine kinase single chain Fv antibodies from a human phage display library. Biochim Biophys Acta. 2002 Dec. 12; 1579(2-3):124-32; Oelschlaeger P et al. Fluorophor-linked immunosorbent assay: a time- and cost-saving method for the characterization of antibody fragments using a fusion protein of a single-chain antibody fragment and enhanced green fluorescent protein. Anal Biochem. 2002 Oct. 1; 309(1):27; Nathan S et al. Phage display of recombinant antibodies toward Burkholderia pseudomallei exotoxin. J Biochem Mol Biol Biophys. 2002 February; 6(1):45-53; Lu D et al. Fab-scFv fusion protein: an efficient approach to production of bispecific antibody fragments. J Immunol Methods. 2002 Sep. 15; 267(2):213-26; Zhang W et al. Production and characterization of human monoclonal anti-idiotype antibodies to anti-dsDNA antibodies. Lupus. 2002; 11(6):362-9; Reiche N et al. Generation and characterization of human monoclonal scFv antibodies against Helicobacter pylori antigens. Infect Immun. 2002 August; 70(8):4158-64; Rau D et al, Single-chain Fv antibody-alkaline phosphatase fusion proteins produced by one-step cloning as rapid detection tools for ELISA. J Immunoassay Immunochem. 2002; 23(2):129-43; and Zhou B et al. Human antibodies against spores of the genus Bacillus: a model study for detection of and protection against anthrax and the bioterrorist threat. Proc Natl Acad Sci USA. 2002 Apr. 16; 99(8):5241-6; Baek H et al., An improved helper phage system for efficient isolation of specific antibody molecules in phage display. Nucleic Acids Res. 2002 Mar. 1; 30(5):e18).
[0071] scFv constructs can be based on antibodies, as in most of the references above, on T-cell receptors (e.g., Epel M et al. A functional recombinant single-chain T cell receptor fragment capable of selectively targeting antigen-presenting cells. Cancer Immunol Immunother. 2002 December; 51(10):565-573), or on other sequences. Different phage coat proteins have been used to display the diverse peptides (see Gao C et al. A method for the generation of combinatorial antibody libraries using pIX phage display. Proc Natl Acad Sci USA. 2002 Oct. 1; 99(20):12612-6). For an example of fusion constructs, see Lu D et al. Fab-scFv fusion protein: an efficient approach to production of bispecific antibody fragments. J Immunol Methods. 2002 Sep. 15; 267(2):213-26.
[0072] For an example of molecular evolution to improve binding affinity, see Rau D et al. Cloning, functional expression and kinetic characterization of pesticide-selective Fab fragment variants derived by molecular evolution of variable antibody genes, Anal Bioanal Chem. 2002 January; 372(2):261-7. Examples of other modifications “to improve affinity or avidity, respectively [include] by mutating crucial residues of complementarity determining regions or by increasing the number of binding sites making dimeric, trimeric or multimeric molecules.” (the quote is from a review article, Pini A & Bracci L, Phage display of antibody fragments. Curr Protein Pept Sci. 2000 September; 1(2):155-169). The initial set of diverse molecules can be enriched by using sequences from animals or humans exposed to or expressing antibodies against the target (see again Zhang W et al. Lupus 2002; and Reiche N et al. Infect Immun 2002).
[0073] Single chain antibodies can also be generated by using Escherichia coli (see Sinacola J R & Robinson A S, Rapid folding and polishing of single-chain antibodies from Escherichia coli inclusion bodies, Protein Expr Purif. 2002 November; 26(2):301-308.)
[0074] Non-antibodies also include aptamers and non-antibodies that comprise aptamers. Aptamers are DNA or RNA molecules that have been selected (e.g., from random pools) on the basis of their ability to bind to another molecule (discussed for example at the web site of the Ellington lab, in the Institute of Cellular and Molecular Biology, at the University of Texas at Austin, http://aptamer.icmb.utexas.edu/), wherein said molecule can be a nucleic acid, a small organic compound, or a protein, peptide, or modified peptide (such as thrombospondin or a portion thereof.). An aptamer beacon is an example of a non-antibody that comprises an aptamer (See Hamaguchi N et al., Aptamer beacons for the direct detection of proteins. Anal. Biochem. 2001 Jul. 15; 294(2):126-131.)
[0075] Angiocidin is a CSVTCG-specific tumor cell adhesion receptor, see patent application WO 0105968, also NCBI protein accession number CAC32386.1 and/or CAC32387.1 (corresponding to nucleotide accession numbers AX077201 and AX077202), the amino acid sequences specified by those two protein accession numbers as of the date of filing of this application being incorporated herein by reference. It is understood that anti-secretory factor cDNA contains essentially identical nucleotide sequence (e.g., accession #U24704, 99% match by BLAST alignment) to that of angiocidin, as does the nucleotide sequence for the proteasome (prosome, macropain) 26S subunit, non-ATPase, 4 (PSMD4; e.g., accession #NM — 002810, also 99% match by BLAST). Anti-secretory factor has the same amino acid sequence as angiocidin, except that AX077201 has a 9-bp insert compared to AX077202, which would mean an additional three amino acyl residues in the encoded protein. Thus, the terms herein are used interchangeably. The NCBI summary for NM — 002810 is as follows: “The 26S proteasome is a multicatalytic proteinase complex with a highly ordered structure composed of 2 complexes, a 20S core and a 19S regulator. The 20S core is composed of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. The 19S regulator is composed of a base, which contains 6 ATPase subunits and 2 non-ATPase subunits, and a lid, which contains up to 10 non-ATPase subunits. Proteasomes are distributed throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. This gene encodes one of the non-ATPase subunits of the 19S regulator lid. Two alternate transcripts encoding two different isoforms have been described. Pseudogenes have been identified on chromosomes 10 and 21. Transcript Variant: This variant (1) encodes the longer protein (isoform 1).” Other names for the protein from the protein accession file (NP — 002801.1) include “proteasome 26S non-ATPase subunit 4 isoform 1; antisecretory factor 1; 26S protease subunit S5a; S5a/antisecretory factor protein; multiubiquitin chain binding protein; 26S proteasome non-ATPase regulatory subunit 4”.
Methods of Producing Antibodies Against the Fragments of the Invention
[0076] In another general aspect, the invention is a method of producing antibodies against an above-noted thrombospondin fragment and/or portion thereof, the method comprising administering such a fragment or portion to an organism (especially a mammal or a bird) capable of producing antibodies. It is understood that said antibodies may comprise monoclonal antibodies and/or polyclonal antibodies. For monoclonal antibodies it is understood that cells from the organism are typically used in the production of hybridomas. For production of antibodies, including monoclonal antibodies, it is understood that any of the thrombospondin fragments and/or portions can be conjugated to a carrier molecule, including but not limited to keyhole limpet hemocyanin and bovine serum albumin, to facilitate the antibody response.
[0077] A cell and a cell line for producing the aforementioned monoclonal antibodies are aspects of the invention. Examples of such cells include, but are not limited to, hybridomas, transfected cell lines, and infected cells.
Kits of the Invention
[0078] Kits related to the above inventions are themselves aspects of the invention. Such kits are, for example, those that facilitate the determination of the presence of and/or the amount of, and/or the concentration of, a thrombospondin fragment or fragments in a material taken or gathered from an organism. Such kits optionally comprise a thrombospondin fragment or fragments, or a portion or portions thereof, of the invention. Such kits can comprise a binding agent or agents specific for a thrombospondin fragment, or portion thereof, of interest. They optionally comprise binding agents that will react with thrombospondin but not a fragment or fragments, and/or a portion or portions thereof, of interest. They optionally comprise binding agents that distinguish between thrombospondin and a fragment, and/or between one fragment and another. If intended for solid tissue, the kits may comprise a homogenizing means for extracting a fragment into a solution, which optionally may also be provided. Binding agents of the current invention can also be used for other well-known detection methods, including but not limited to immunohistochemistry.
[0079] Preferred binding agents are proteins, although non-proteins are also contemplated. Such proteins include both antibodies and nonantibodies.
[0080] Optionally, the kits comprise a means for separating or distinguishing a fragment or fragments (or portions thereof) from thrombospondin. The kits can also include a thrombospondin fragment, a peptide derived from such fragment, or a derivatized fragment or peptide, to facilitate detection and calibration.
[0081] In one set of embodiments, the kits are adapted for use in an automated assay, such as one using a clinical autoanalyzer.
[0082] Particular kit aspects of the invention can also be summarized as follows:
[0083] A kit for the determination of the presence of, and/or the amount of, and/or the concentration of, a thrombospondin fragment or fragments in a material taken or gathered from an organism, said kit comprising a thrombospondin fragment or portion thereof.
[0084] A kit for the determination of the presence of, and/or the amount of, and/or the concentration of, one or more thrombospondin fragments in a material taken or gathered from an organism, said kit comprising a binding agent capable of binding said one or more fragments.
[0085] Particular embodiments are:
[0086] Such kits wherein the binding agent comprises a protein.
[0087] Such kits wherein said protein comprises an antibody.
[0088] Such kits wherein the antibody is a monoclonal antibody or a polyclonal antibody.
[0089] Such kits wherein said protein comprises a fragment of an antibody.
[0090] Such kits wherein said protein comprises a single-chain antibody.
[0091] Such kits wherein said single chain antibody is derived from a phage display library.
[0092] Such kits wherein said protein is a non-antibody, the non-antibody being a protein that is neither a multi-chain antibody nor a single-chain antibody.
[0093] Such kits wherein said protein non-antibody is selected from the group consisting of a thrombospondin receptor, a thrombospondin receptor that binds within a protease-resistant core region, a thrombospondin receptor that binds a TSP fragment present in the plasma of a cancer patient, a CSVTCG receptor, a CSVTCG binding molecule, a CD36 (which reportedly binds CSVTCG; see Carron J A et al., A CD36-binding peptide from thrombospondin-1 can stimulate resorption by osteoclasts in vitro. Biochem Biophys Res Commun. 2000 Apr. 21; 270(3):1124-7), angiocidin, anti-secretory factor, 26S proteasome non-ATPase regulatory subunit 4, fragments thereof that bind to their respective targets, and combinations, chimeras, and recombinant versions of said receptors and fragments.
[0094] Such kits wherein said binding agent comprises a non-protein.
[0095] Such kits wherein said binding agent comprises an aptamer.
[0096] Such kits wherein said binding agent comprises angiocidin, anti-secretory factor, and/or 26S proteasome non-ATPase regulatory subunit 4.
[0097] Other particular kit aspects of the invention can be summarized as follows:
[0098] A kit for the determination of the presence of, and/or the amount of, and/or the concentration of, one or more thrombospondin fragments in a material taken or gathered from an organism, said kit comprising a binding agent that will react with thrombospondin but not with a fragment of interest. Particular embodiments are:
[0099] Such kits wherein said binding agent comprises a protein;
[0100] Such kits wherein said protein comprises an antibody;
[0101] Such kits wherein said antibody is a monoclonal antibody or a polyclonal antibody;
[0102] Such kits wherein said protein comprises a fragment of an antibody;
[0103] Such kits wherein said protein comprises a single-chain antibody;
[0104] Such kits wherein said single chain antibody is derived from a phage display library;
[0105] Such kits wherein the protein is a non-antibody, the non-antibody being a protein that is neither an antibody nor a single-chain antibody;
[0106] Such kits wherein said non-antibody is selected from the group consisting a an integrin, an RGD receptor, an RFYVVMWK receptor, an RFYVVM receptor, an FYVVMWK receptor, an IRVVM receptor, fragments thereof that bind to their respective targets, and combinations, chimeras, and recombinant versions of said receptors, integrins, and fragments; and
[0107] Such kits wherein said binding agent comprises an aptamer, meaning a DNA or RNA or related compound, that binds thrombospondin or a thrombospondin fragment.
[0108] Such kits wherein said binding agent comprises angiocidin, anti-secretory factor, and/or 26S proteasome non-ATPase regulatory subunit 4.
[0109] Several motifs within thrombospondin for binding to many of the receptors referred to above are shown in in FIG. 2.2a of Adams, J. C., et al., The thrombospondin Gene Family, Springer Verlag, New York, 1995, p. 16. A CSVTCG receptor, a CSVTCG binding molecule, an angiocidin, an anti-secretory factor, a CD36, and/or fragments and derivatives thereof will be useful for assaying a thrombospondin fragment in a cancer patient.
Focus on Neoplastic Disease
[0110] The invention as it pertains to the detection or monitoring of neoplastic disease can also be summarized as the following:
[0111] A method to detect the presence of neoplastic disease in an individual, wherein the method comprises the steps of:
[0112] (1) measuring the individual's plasma level of a thrombospondin fragment;
[0113] (2) utilizing the result of step (1) in a diagnosis as to whether the individual has a neoplastic disease; said fragment being at least 6 contiguous amino acyl residues in length but less than 110 kDa (preferably less than 100 kDa).
[0114] Related is such a method, where the individual referred to therein is a first individual and wherein the method further comprises the steps of:
[0115] (3) measuring a second individual's plasma level of the thrombospondin fragment, said second individual considered to not have neoplastic disease;
[0116] (4) utilizing the result of step (3) is the diagnosis of whether the first individual has a neoplastic disease. For example, such a method wherein the greater the extent to which the first individual's plasma thrombospondin fragment level exceeds the plasma thrombospondin level of the second individual, the more likely that the diagnosis will be that the first individual has a neoplastic disease and/or a neoplastic disease more advanced than that of the second person. It is also understood that values from the first individual taken over time can be compared with one another, to assess the likelihood of the appearance of disease and/or progression and/or regression of disease. Particular embodiments are:
[0117] Such methods wherein the fragment is selected from the group consisting of an ˜85 to 90 kDa fragment, and ˜50 kDa fragment, and an ˜30kDa fragment, wherein the size in kDa is that determined by gel electrophoresis after disulfide bond reduction;
[0118] Such methods wherein the neoplastic disease is selected from the group consisting of an adenoma, adenocarcinoma, carcinoma, lymphoma, leukemia, and sarcoma;
[0119] Such methods wherein the neoplastic disease is an internal cancer;
[0120] Such methods wherein the neoplastic disease is selected from the group consisting of a cancer of the respiratory system, a cancer of the circulatory system, a cancer of the musculoskeletal system, a cancer of a muscle, a cancer of a bone, a cancer of a joint, a cancer of a tendor or ligament, a cancer of the digestive system, a cancer of the liver or biliary system, a cancer of the pancreas, a cancer of the head, a cancer of the neck, a cancer of the endocrine system, a cancer of the reproductive system, a cancer of the male reproductive system, a cancer of the female reproductive system, a cancer of the genitourinary system, a cancer of a kidney, a cancer of the urinary tract, a skin cancer, a cancer of other sensory organs (such as eye, ear, nose, tongue), a cancer of the nervous system, a cancer of a lymphoid organ, a blood cancer, a cancer of a gland, a cancer of a mammary gland, a cancer of a prostate gland, a cancer of endometrial tissue, a cancer of mesodermal tissue, a cancer of ectodermal tissue, and a teratoma;
[0121] Such methods wherein the neoplastic disease is selected from the group consisting of a cancer of solid tissue, a cancer of the blood or the lymphatic system, a non-metastatic cancer, a premetastic cancer, a metastatic cancer, a poorly differentiated cancer, a well-differentiated cancer, and a moderately differentiated cancer.
[0122] Such methods wherein the measurement of a plasma thrombospondin fragment level comprises the use of a binding agent, said binding agent being capable of binding said thrombospondin fragment (Such binding agents are discussed above in the context of the kits of the invention); and
[0123] In particular embodiments, the thrombospondin fragment is separated from thrombospondin before said fragment is bound to the binding agent.
[0124] Such methods wherein said method comprises the use of a binding agent, comprising a binding agent capable of binding thrombospondin but not the thrombospondin fragment. Possible binding agents are discussed above in the context of kits of the invention.
[0125] In particular embodiments, the thrombospondin fragment is separated from thrombospondin before said fragment is bound to the binding agent.
[0126] Related inventions are:
[0127] A method of producing antibodies against a thrombospondin fragment, said method comprising administering said fragment to an organism capable of producing antibodies;
[0128] Said method of producing antibodies wherein said fragment is at least 6 amino acyl residues in length but less than 110 kDa (preferably less than 95 kDA). A polyclonal antibody preparation produced by said method;
[0129] A monoclonal antibody produced by said method;
[0130] A cell line producing said monoclonal antibody; and
[0131] A method of producing a binding agent against a thrombospondin fragment, said method comprising the use of phage display.
[0132] Said method of producing a binding agent, wherein said method comprises the selection of a thrombospondin-binding or thrombospondin fragment-binding phage from a phage display.
[0133] Said method of producing a binding agent, wherein said fragment at least 6 amino acyl residues in length.
Cancer Detection Method Comprising Measuring Platelet Activation
[0134] An additional general aspect of the invention is an assay for the presence of cancer in an organism, said method comprising measuring the extent of platelet activation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0135] FIG. 1 . Schematic drawing of thrombospondin.
[0136] FIG. 2 . Results of staining a gel with Coomasie Blue. Lanes, left to right are in the sequence: a lane with the molecular weight standards (Stds), followed by samples A to G.
[0137] FIG. 3 . Results of Western Blot analysis using TSP Ab-4 antibody and fluorescence detection. Lanes, left to right are in the sequence: a lane with the molecular weight standards (Stds), followed by samples A to G, which correspond to aliquots of the same samples as in FIG. 2 .
[0138] FIG. 4 . Analysis of the same samples as for FIG. 3 , using urea denaturation before electrophoresis, followed by electrophoresis through a 12% acrylamide gel and enzymatic colorometric detection after blotting.
DETAILED DESCRIPTION OF THE INVENTION
[0139] The terms “thrombospondin” and “thrombospondin-1” are used interchangeably herein. It is understood that a single “band” on an electrophoresis gel may in fact reflect the presence of a collection of fragments that together form a population that, during gel electrophoresis under reducing conditions, electrophorese at similar rates.
[0140] The terms “test” and “assay” are also used interchangeably.
[0141] A “purified” fragment is for example (1) one that is found in human plasma and that has been purified (for example has been isolated from gels on which the plasma has been electrophoresed). A purified fragment is not one that is in human plasma, or other part of a human, and that has not undergone at least some degree of purification.
[0142] A “synthesized fragment” is, for example, one that has been synthesized in a laboratory (e.g., by recombinant DNA technology or by chemical synthesis) so as to have the primary structure of such a fragment or a portion thereof.
[0143] The amino acid sequence of human thrombospondin-1 from GenBank is:
ACCESSION NM — 003246 (protein_id=NP — 003237.1) VERSION NM 003246.1 GI:4507484
[0000]
(SEQ ID NO: 38)
MGLAWGLGVLFLMHVCGT N RIPESGGDNSVEDIFELTGAARKGSGRRLVK
GPDPSSPAFRIEDANLIPPVPDDKFQDLVDAVRAEKGFLLLASLRQMKKT
RGTLLALERKDHSGQVFSVVSNGKAGTLDLSLTVQGKQHVVSVEEALLAT
GQWKSITLFVQEDRAQLYIDCEKMENAELDVPIQSVFTRDLASIARLRIA
KGGVNDNFQGVLQNVRFVFGTTPEDILRNKGCSSSTSVLLTLDNNVVNGS
SPAIRTNYIGHKTKDLQAICGISCDELSSMVLELRGLRTIVTTLQDSIRK
VTEENKELANELRRPPLCYHNGVQYRNNEEWTVDSCTECHCQNSVTICKK
VSCPIMPCSNATVPDGECCPRCWPSDSADDGWSPWSEWTSCSTSCGNGIQ
QRGRSCDSLNNRCEGSSVQTRTCHIQECDKRFKQDGGWSHWSPWSSCSVT
CGDGVITRIRLCNSPSPQMNGKPCEGEARETKACKKDACPINGGWGPWSP
WDICSVTCGGGVQKRSRLCNNPAPQFGGKDCVGDVTENQICNKQDCPIDG
CLSNPCFAGVKCTSYPDGSWKCGACPPGYSGNGIQCTDVDECKEVPDACF
NHNGEHRCENTDPGYNCLPCPPRFTGSQPFGQGVEHATANKQVCKPRNPC
TDGTHDCNKNAKCNYLGHYSDPMYRCECKPGYAGNGIICGEDTDLDGWPN
ENLVCVANATYHCKKDNCPNLPNSGQEDYDKDGIGDACDDDDDNDKIPDD
RDNCPFHYNPAQYDYDRDDVGDRCDNCPYNHNPDQADTDNNGEGDACAAD
IDGDGILNERDNCQYVYNVDQRDTDMDGVGDQCDNCPLEHNPDQLDSDSD
RIGDTCDNNQDIDEDGHQNNLDNCPYVPNANQADHDKDGKGDACDHDDDN
DGIPDDKDNCRLVPNPDQKDSDGDGRGDACKDDFDHDSVPDIDDICPENV
DISETDFRRFQMIPLDPKGTSQNDPNWVVRHQGKELVQTVNCDPGLAVGY
DEFNAVDFSGTFFINTERDDDYAGFVFGYQSSSRFYVVMWKQVTQSYWDT
NPTRAQGYSGLSVKVVNSTTGPGEHLRNALWHTGNTPGQVRTLWHDPRHI
GWKDFTAYRWRLSHRPKTGFIRVVMYEGKKIMADSGPIYDKTYAGGRLGL
FVFSQEMVFFSDLKYECRDP
[0146] The underlined N in the first line of the sequence above refers to amino acid number 1 of the mature protein (i.e., without the 18- to 22-residue signal peptide sequence, here assumed to be 18 residues; see p. 13 and FIG. 1 in Adams J C et al. The Thrombospondin Gene Family, 1995).
[0147] Here is a partially annotated version of the human TSP-1 sequence from GenBank, broken into domains, and including indications of some of the functional regions that have been identified in the literature.
MGLAWGLGVLFLMHVCGT (SEQ ID NO: 39) [The signal peptide is considered to be 18-22 residues long (18 residues assumed here, following The Thrombospondin Gene Family by J C Adams et al. 1995)] N RIPESGGDNSVFDIFELTGAA RKGSGRRLVK GPDPSSPAFRIEDANLIPPVPDDKFQDLVD AVRAEKGFLLLASL RQMKKTR GTLLALERKDHSGQVFSVVSNGKAGTLDLSLTVQGKQHVVS VEEALLATGQWKSITLFVQEDRAQLY IDCEKMENAELDVP IQSVFTRDLASIARLRIAKGGV NDNFQGVLQNVRFVFGTTPEDILRNKGCSSSTSVLLTLDNNVVNGSSPAIRTNY(SEQ ID NO: 40) [N-terminal domain (1-240). The underlined N at the beginning of this domain refers to amino acid number 1 of the mature protein (i.e., without the 18- to 22-residue signal peptide sequence, here assumed to be 18 residues; see p. 13 and FIG. 1 in Adams J C et al. The Thrombospondin Gene Family, 1995). Two apparent heparin-binding regions are double-underlined. Finally, the last underlined region in this domain corresponds to “synthetic peptide N12/I encompassing amino acid residues 151-164 of the N-terminal domain of TSP-1”, which was reported to bind fibrinogen.] IGHKTKDLQAI C GIS C DELSSM (SEQ ID NO: 41) [Domain of inter-chain disulfide bonds (241-262)] VLELRGLRTIVTTLQDSIRKVTEENKELANELRRPPLCYHNGVQYRNNEEWTVDSCTECHC QNSVTICKK VSCPIMPCSNATVPDGECCPRCWPSDSA [(SEQ ID NO: 42) [Procollagen homology domain (263-360). Notice that the collagen V-binding region (valine[333] to lysine[412]), which is double underlined here, is partly in this domain and partly in the first type 1 repeat, which immediately follows this domain.] DDGWSPWSEWTSCSTSCGNGIOQRGRSCDSLNNRCEGSSVQTRTCHIQECDK RFKQ DGGWSHWSPWSSCSVTCGDGVITRIRLCNSPSPQMNGKPCEGEARETKACKKDACPI NGGWGPWSPWDICSVTCGGGVQKRSRLCNNPAPQFGGKDCVGDVTENQICNKQDCPI (SEQ ID NO: 43) [Domain of type 1 repeats (361-530). This domain consists of three type 1 repeats. The double-underlined segment at the beginning of this domain is the continuation of the collagen V-binding region (valine[333] to lysine[412]).] DGCLSNPCFAGVKCTSYPDGSWKCGACPPGYSGNGIQCTDV DECKEVPDACFNHNGEHRCENTDPGYNCLPCPPRFTGSQPFGQGVEHATANKQVCKPR NPCTDGTHDCNKNAKCNYLGHYSDPMYRCECKPGYAGNGIICGE (SEQ ID NO: 44) [Domain of type 2 repeats (531-673). This domain consists of three type 2 repeats.] DTDLDGWPNENLVCVANATYHCKK (SEQ ID NO: 45) [Region between the type 2 and the type 3 repeat (674-697)] DNCPNLPNSGQEDYDKDGIGDACDDDDDNDKIPDDR (SEQ ID NO: 46) DNCPFHYNPAQYDYDRDDVGDRC (SEQ ID NO: 47) DNCPYNHNPDQADTDNNGEGDACAADIDGDGILNER (SEQ ID NO: 48) DNCQYVYNVDQRDTDMDGVGDQC (SEQ ID NO: 49) DNCPLEHNPDQLDSDSDRIGDTCDNNQDIDEDGHQNNL (SEQ ID NO: 50) DNCPYVPNANQADHDKDGKGDACDHDDDNDGIPDDK (SEQ ID NO: 51) DNCRLVPNPDQKDSDGDGRGDACKDDFDHDSVPDID (SEQ ID NO: 52) [Domain of type 3 repeats (698-925). This domain consists of seven type 3 repeats.] DICPENVDISETDFRRFQMIPLDPKGTSQNDPNWVVRHQGKELVQTVNCDPGLAVGYDEFN AVDFSGTFFINTERDDDYAGFVFGYQSSSRFYVVMWKQVTQSYWDTNPTRAQGYSGLSVKV VNSTTGPGEHLRNALWHTGNTPGQVRTLWHDPRHIGWKDFTAYRWRLSHRPKTGFIRVVMY EGKKIMADSGPIYDKTYAGGRLGLFVFSQEMVFFSDLKYECRDP (SEQ ID NO: 53)
[0163] [C-terminal domain (926-1152)]
[0164] It is understood that genetic variants of thrombospondin exist, including but not limited to human polymorphisms (e.g., see dbSNP:2229364, dbSNP:2228261, dbSNP:2292305, dbSNP:2228262, and dbSNP:2228263 for variants in the coding region; and dbSNP:1051442, dbSNP:3743125, dbSNP:3743124, dbSNP:1051514, dbSNP:1131745, and dbSNP:11282 for 3′ UTR variants). The current invention contemplates assays that detect polymorphic variants as well as common types involving the coding region, either through the use of an antibody or antibodies or other binding molecule or molecules that recognize variant and common peptide sequences, and/or through the use of sequences that are not polymorphic. It is understood that A-505 [alanine(505)] in the GenBank sequence NM — 003246 is instead given as a T [threonine(505)] in FIG. 2.2a of Chapter 2, “The primary structure of the thrombospondins” in The Thrombospondin Gene Family by J C Adams, R P Tucker, & J Lawler, Springer-Verlag: New York, 1995, p. 16.
[0165] It is believed that the collagen type V binding domain corresponds to the region extending from valine(333) and lysine(412) of thrombospondin-1 (Takagi T et al. J Biol Chem 268:15544-15549, 1993; here, the residue numbers refer to the mature protein). Thus, the collagen type V-binding region would include a portion of the procollagen homology region of thrombospondin and all or nearly all of the first type 1 repeat of thrombospondin (see Chapter 2, “The primary structure of the thrombospondins” in The Thrombospondin Gene Family by J C Adams, R P Tucker, & J Lawler, Springer-Verlag: New York, 1995, pp. 11-42, but especially p. 24). See FIG. 1 of this application, as well as the annotated TSP sequence, above. As indicated on the FIG. 1 of this application, the leftmost rectangle represents the N-terminal domain (mature residues 1 to ˜240), which contains heparin-binding sequence; the short vertical lines represent Cys(252) and Cys(256) of human thrombospondin-1, which are involved in inter-chain disulfide bonds, to form trimers; the first oval represents the procollagen homology domain (residues 263-360); the three slanted ovals represent the three type 1 repeats (residues 361-530), which resemble properidin and a malarial protein; the three tall ovals represent the three type 2 repeats (residues 531-673), which show similarities to the epidermal growth factor (EGF) repeat; there is a short sequence (residues 674-697) separating type 2 and type 3 repeats; the seven ovals represent the seven type 3 repeats (residues 698-925), which are rich in aspartic acid and resemble the calcium-binding pocket of parvalbumin or calmodulin; and right-hand square represents the C-terminal cell-binding domain (residues 926 to the end, that is, Proline-1152; see FIG. 2.2a in Adams J C et al. The Thrombospondin Gene Family, 1995, p. 16). The two chymotryptic fragments (70- and 50-kDa), and to some extent the 120-kDa tryptic fragment, indicated schematically on FIG. 1 , correspond to the protease-resistant central core domain of thrombospondin.
[0166] Examples of cancers that can be detected using assays for the thrombospondin fragments include but are not limited to: adenoma, adenocarcinoma, carcinoma, lymphoma, leukemia, sacrcoma, solid cancer, liquid cancer, metastatic cancer, pre-metastatic cancer, non-metastatic cancer, a cancer with vascular invasion, internal cancer, skin cancer, cancer of the respiratory system, cancer of the circulatory system, cancer of the musculoskeletal system, cancer of a muscle, cancer of a bone, cancer of a joint, cancer of a tendor or ligament, cancer of the digestive system, cancer of the liver or biliary system, cancer of the pancreas, cancer of the head, cancer of the neck, cancer of the endocrine system, cancer of the reproductive system, cancer of the male reproductive system, cancer of the female reproductive system, cancer of the genitourinary system, cancer of a kidney, cancer of the urinary tract, cancer of a sensory system, cancer of the nervous system, cancer of a lymphoid organ, a blood cancer, cancer of a gland (for example but not limited to cancer of a mammary or a prostate gland), cancer of an endometrial tissue, cancer of a mesodermal tissue, cancer of an ectodermal tissue, cancer of an endodermal tissue, a teratoma, a poorly-differentiated cancer, a well-differentiated cancer, and a moderately differentiated cancer.
[0167] One of the options for tests for the presence of thrombospondin fragments is to fractionate the material (e.g., plasma) into fractions (e.g., positions on an electrophoresis gel, or chromatographic elution samples) collected by a technique capable of separating the fragments from thrombospondin (e.g., by electrophoresis, size-dependent chromatography, and/or affinity chromatography) and to detect the fragments in the fractions where such fragments would be expected to appear. Another of the various additional known options for assays is to test the ability of plasma to inhibit the binding of thrombospondin fragments or portions thereof to compounds (e.g., antibodies) that specifically bind to them.
[0168] The thrombospondin fragments of primary interest in the diagnostic tests are ones that have apparent molecular weights of ˜85 kDa (or ˜90 kDA), ˜50 kDa, and ˜30 kDa as determined by SDS-PAGE electrophoresis after reduction (see FIGS. 3 and 4 ). Preferred conditions for determining the molecular weights are those referred to below as “Standard Gel Electrophoresis Protocol.” The assignment of a number such as 50 kDa to the size of a fragment reflects its approximate molecular weight as determined using the Standard Gel Electrophoresis Protocol.
[0169] It is believed that the ˜85 kDa, ˜50 kDa, and ˜30 kDa fragments all contain an immunogenic portion of “collagen type V-binding domain” of thrombospondin. In a preferred aspect of the invention, the fragments are detected by antibody that binds to such a domain, as is believed to be the case for the TSP Ab-4 monoclonal antibody referred to below. Because the collagen V-binding domain is relatively small (˜19 kDa; see Takagi et al. J B C 1993), it is concluded from the apparent molecular weights of these fragments, which are substantially greater than 19 kDa, that additional portions of the thrombospondin molecule must also be present in these fragments (multimers of the 19-kDa region are not a plausible explanation for the higher molecular weights, because the 19-kDa region does not comprise the region of inter-chain disulfide bonds, plus the fact that the gels in FIGS. 3 and 4 were run under reducing conditions). It is believed that additional portions come from the protease-resistant central core domain of thrombospondin, which can be selected from the group of thrombospondin domains consisting of the region of inter-chain disulfide bonds, the procollagen-like domain, a type 1 repeat, and to some extent a type 2 repeat and a type 3 repeat (see Prater C A et al. The properdin-like type 1 repeats of human thrombospondin contain a cell attachment site. J Cell Biol. 1991 March; 112(5):1031-40; Schultz-Cherry Set al. The type 1 repeats of thrombospondin 1 activate latent transforming growth factor-beta. J Biol Chem. 1994 Oct. 28; 269(43):26783-8; FIG. 6.2 in Adams J C et al. The Thrombospondin Gene Family, 1995, p. 107; and chymotryptic and tryptic fragments of thrombospondin indicated schematically in FIG. 1 of this application). See also the sequence ranges given earlier in this Application. Note that several aforementioned peptides, such as, CNSPSPQMNGKPCEGEAR (residues 444-461), RKVTEENKELANELRPP residues 281-297); PQMNGKPCEGEAR (residues 449-461); CEGEAR (residues 456-461; and RKVTEENKE (residues 281-289) are within the protease-resistant central core domain. An antibody against a region outside of a collagen V-binding domain, but present in a thrombospondin fragment present in a cancer patient, is also preferred.
[0170] In competition assays, a sample of material (e.g., plasma) that contains thrombospondin fragment(s) and/or thrombospondin is tested for its ability to interfere with the binding of one (or more) of the fragments to a fragment-specific binding agent, preferably an antibody, such as a monoclonal antibody. Under optimal conditions, the ability of the sample to interfere with the binding of the fragment increases monotonically in relation to the amount of similarly binding fragments in the sample. Thrombospondin will also interfere with the binding, but the present inventor has discovered that thrombospondin is present in plasma in significantly smaller amounts than the fragments. In addition, competition assays are easily standardized through the use of known quantities of fragments, synthetic or otherwise, and/or through the use of molecules, such as peptides, that contain an epitope recognized by the binding agent. In one scenario, assay detection is accomplished through the use of labeled fragments and/or peptides, and addition of a sample that contains a thrombospondin fragment or addition of known quantities of an unlabeled thrombospondin fragment (as a standard) results in competition with the binding of the labeled fragments and/or peptide to the binding agent. Loss of signal upon addition of known quantities of unlabeled or differently labeled thrombospondin fragments is used to standardize the assay.
[0171] In addition to an assay of thrombospondin fragments, other examples of platelet activation assays include but are not limited to: a thromboxane assay, a B2 assay, a beta-thromboglobulin (BTG) assay, a platelet-derived growth factor assay, a fibronectin assay, a fibrinogen assay, and a platelet factor 4 assay. Each of these can be assayed by antibody-based assays, such as an ELISA or a competive ELISA, as is well-known in the art. Platelet activation, including the formation of platelet thrombi, is also indicated by markers that include membrane constituents, such as P selectin (which can be assayed, for example, as soluble P-selectin, which is generated as an alternatively spliced form or is proteolytically released from membrane-bound P-selectin), gpV, and glycocalicin (see Gurney D et al.: A reliable plasma marker of platelet activation: Does it exist? Am J Hematol. 2002 June; 70(2):139-44; glycocalicin is the extracellular domain of GP Ibalpha, which can be released from Gp Ib/V/IX complexes on platelets, see Baglia F A et al.: Factor XI binding to the platelet glycoprotein Ib-IX-V complex promotes factor XI activation by thrombin. J Biol Chem. 2002 Jan. 18; 277(3):1662-8), as well as platelet microparticles (see Michelson A D & Furman M I: Laboratory markers of platelet activation and their clinical significance. Curr Opin Hematol. 1999 September; 6(5):342-8; Nomura S et al.: Relationship between platelet activation and cytokines in systemic inflammatory response syndrome patients with hematological malignancies. Thromb Res. 1999 Sep. 1; 95(5):205-13; Nomura S et al.: Function and clinical significance of platelet-derived microparticles. Int J Hematol. 2001 December; 74(4):397-404) and certain prostanoids. Assays of these are also well-known in the art.
Detection of Thrombospondin Fragments by Western Blot Analysis
[0172] The following protocol (Sections I, II, and III) is referred to herein as the “Standard Gel Electrophoresis Protocol” and is preferred for determining whether the size of a fragment is ˜85 kDa, ˜50 kDa, ˜30 kDa or another size. Nevertheless, suitable alternatives for fractionating and detecting molecules and molecular fragments are well-known in the art (see numerous methods articles and texts, as well as protocols from commercial sources) and are readily applied to the current situation with appropriate modifications.
I. Sample Preparation
[0000]
Protease inhibitors added:
1 μl of leupeptin solution (1 mg/ml in sterile water) is added per ml plasma
10 μl of PMSF solution (1.74 mg /ml in isopropanol) is added per ml plasma
4× sample buffer:
dH 2 O 4.0 ml/0.5M tris-HCl 1.0 ml/glycerol 0.8 ml/10% SDS 1.6 ml/2-mercaptoethanol
0.4 ml/0.05% bromophenol blue 0.2 ml
5 μl plasma samples are diluted with 20 μl distilled water, and 25 μl 2× sample buffer is added, followed by heating (to aid disulfide bond reduction).
10 μl of each sample mixture is then run on the gel.
[0181] In an example of an alternative to the Standard Gel Electrophoresis Procedure, to aid reduction and denaturation, blood plasma is mixed with 5% fresh mercaptoethanol and 4-6 M fresh urea and boiled for at least 5 minutes in a fume hood.
II. Electrophoresis
[0182] Gel electrophoresis is done on SDS-polyacrylamide gels (4% stacking, 10% running gel) in tris/glycine/SDS buffer (see running buffer below, pH 8.3) at 200 V/7-8 cm at 25° C. for 34 minutes. Alternative electrophoretic set-ups and procedures are well-known in the art and can be used (e.g., using gels of about 8%-12% acrylamide; omission of the stacking gel), but should reliably separate 185 kDa, 85 kDa, 50 kDa, and 30 kDa (these are the approximate apparent weights on a reducing gel of thrombospondin and of the three major thrombospondin fragments in plasma). Molecular weight standards were: 184 kDa, 121 kDa, 86 kDa, 67 kDa, 52 kDa, 40 kDa, 28 kDa, and 22 kDa ( FIG. 3 ). Other molecular weight markers are suitable as well, but should include markers near to 185 kDa (the approximate weight of thrombospondin on reducing gels) and near to 85, 50, and 30 kDa (the approximate weights on reducing gel of the major thrombospondin fragments present in plasma). Suitable molecular weight standards are purchasable from a variety of commercial sources, such as Invitrogen Life Technologies (http://www.invitrogen.com/).
[0183] 5× running buffer pH 8.3: Tris Base 15 g/Glycine 72 g/SDS 5 g/distilled water to 1 liter
[0184] The ˜85-kDa thrombospondin fragment electrophoreses close to the 86 kD standard.
[0185] The ˜50-kDa thrombospondin fragment electrophoreses close to the 52 kD standard.
[0186] The ˜30-kDa thrombospondin fragment electrophoreses close to the 28-kDa standard.
III. Detection of the Fragments on the Gels
[0187] The fragments may be detected by the Western Blot procedure using antibodies that react with the 85 kDa, 50 kDa, and 30 kDa fragments. TSP Ab-4 antibodies from Lab Vision Corporation (Fremont, Calif.; http://www.labvision.com/) can be used for this purpose (as primary antibody), as can polyclonal anti-TSP antibodies (such as Ab-8, a rabbit polyclonal antibody from Lab Vision). Following standard protocols, proteins from the polyacrylamide gel are transferred to a suitable membrane, unoccupied protein-binding sites of the membrane are then blocked (e.g., by incubation with skim milk), and the membrane is exposed to primary antibody. The presence of TSP Ab-4 antibodies that have bound to thrombospondin or thrombospondin fragments on the membrane can be detected by reacting those antibodies with fluorophore-labeled antibodies against mouse IgG (secondary antibody, i.e., that themselves react with the TSP Ab-4 antibodies), followed by subsequent fluorescence-based scanning of the membrane. Detection of polyclonal anti-TSP antibodies is performed similarly, using appropriate secondary antibodies. Other systems for detection of primary antibody are well-known in the art, including but not limited to other systems for labeling a secondary antibody, such as conjugation to an enzyme, such as horseradish peroxidase. Biotin-avidin systems are also well-known in the art, as are radioactive labeling methods.
Determination of Albumin Concentration in Plasma Samples for Purposes of Normalizing the Western Blot Results.
[0188] Gels are run under the same conditions as for the Western Blot, but then stained with Coomasie Blue. The major band (which is near the 67-kDa standard) is albumin, which is quantified by densitometric scanning.
Illustrative, but Not Restrictive, Examples of Quantitative Assays for TSf (i.e., a Thrombospondin Fragment or Fragments):
[0189] Enzyme-linked immunoabsorbant assays (ELISA) and related approaches are well-known in the art (for an example of an ELISA of thrombospondin, but not directed towards thrombospondin fragments, see Tuszynski, G. P., Switalska, H. I., and Knudsen, K.: Modern Methods in Pharmacology in “Methods of Studying Platelet-Secreted Proteins and the Platelet Cytoskeleton,” Vol. 4, Alan R. Liss, Inc., New York, p. 267-286, 1987). Two types of ELISAs are competitive ELISAs, which require only one anti-TSf antibody, and sandwich ELISAs, which can require two anti-TSf antibodies. Essentially identical assays are also contemplated, in which a binding agent other than an antibody is used.
[0190] For a competitive ELISA or ELISA-like assay, two sets of wells can be used, one a set of reaction wells and the other a set of pre-mix wells. In the reaction wells, antigen is bound to a surface, such as a plate or a bead (for simplicity, the rest of this description refers to such a surface as a plate or a well, but it is understood that other surfaces can also be used). Here, the antigen would be based on a thrombospondin fragment present in a cancer patient. Said antigen could take a form selected from the group consisting of thrombospondin (TSP) itself, a TSP fragment found in a cancer patient, a TSP fragment that contains a TSP fragment found in a cancer patient, a TSP fragment that is contained within a TSP fragment found in a cancer patient, a peptide that contains an epitope from a TSP fragment in a cancer patient (where said peptide can be synthetic), and a derivatized peptide and/or fragment. The essential requirement for the fragment, protein or peptide coated on the walls is that it can compete with the TSP fragment of interest (for example a fragment in a patient's plasma) for binding to a binding agent, such as an antibody, used in the ELISA. As an illustration, TSP itself can be used, as stated above. TSP can be prepared by activating platelets in vitro (which then release TSP-1), followed by purification of this TSP from the platelet-conditioned medium; if standard 96-well microtiter plates are used, 75 ng of TSP-1 in 200 μL of phosphate-buffered saline can be added per well. Corresponding amounts (molar or mass) of TSP fragments and/or peptides can be used instead, and are preferable, based on ease of preparation and standardization. After binding the antigen to the immobilized surface, additional binding sites on the surface are blocked by standard protocols (for example, incubation with bovine serum albumin then Tween, both in phosphate-buffered saline).
[0191] The premix wells are prepared with no antigen, but then blocked (e.g., with BSA then Tween). These premix wells can be used as convenient reaction vessels for the initial binding of anti-TSf antibody with either known amounts of antigen in solution (for a standard curve) or unknown amounts of antigens in a sample to be tested (see the next two paragraphs).
[0192] In order to generate a standard curve, to the pre-mix wells are added different concentrations of a standard antigen in solution. The standard antigen might (as described elsewhere herein) be selected so as to quantify the amount of thrombosopondin fragments of the invention, the amount of a subset of thrombospondin fragment or fragments, the amount of thrombsopondin, or their combined total. The antigen may be synthetic, isolated from a cancer patient, isolated from an individual without cancer, or isolated from any other appropriate source, including but not limited to recombinant material. As indicated above, the immobilized antigen in the reaction wells and the antigen in solution in the pre-mix wells do not have to be the same, but they should both react with—and thereby eventually compete for—the binding agent (such as a primary antibody) used in the assay. As an illustrative example, if TSP-1 itself is the standard antigen in solution in the premix wells, 0, 2, 5, 10, 20, 40, 60, and 80 ng can be added per well, in PBS-Tween, in volume of 110 uL per microtiter well. Corresponding amounts (molar or mass) of TSP fragments or peptides can be used instead, and are preferable, based on their ease of preparation and standardization. These wells will be used to generate a standard curve.
[0193] Unknowns (i.e., samples in which it is desired to quantify the concentration of a TSP fragment) are also added, to separate pre-mix wells. For plasma samples, it is typical to dilute them beforehand, say, with PBS-Tween. This can be important, to bring the amount of TSf down into the range of the standard curve, and also to dilute potentially interfering substances in plasma (one such interfering substance may be fibrinogen, which can bind TSP and some TSP fragments). Total volume should be the same as for the soluble antigen standards. Diluted binding agent, such as an antibody (e.g., in 110 uL), that reacts against a TSP fragment found in a cancer patient is then added. Note that the antigen immobilized in the reaction wells and the antigen in solution in the pre-mix wells must be chosen to also react against this binding agent. An incubation is performed, to allow antigen-antibody binding (or target-binding agent binding) to occur in the pre-mix wells.
[0194] An aliquot (e.g., 200 uL) of liquid from each premix well (standards and unknowns) is then transferred to an antigen-coated reaction well, followed by an incubation (as a blank, some wells can receive buffer only, such as PBS-Tween). After this incubation, liquid is removed from the antigen-coated reaction wells, and the wells are washed. If a primary antibody is used as the binding agent, enzyme-conjugated secondary antibody (specific against the primary antibody) is then added to the wells, followed by an incubation to allow it to bind to whatever primary antibody has bound to the immobilized TSf on the plate. This step is followed by detection (for example, if the secondary antibody is conjugated to alkaline phosphatase, detection can be accomplished with Sigma phosphatase substrate followed by absorbance readings at 405 nm). A standard curve is plotted, and quantities of a TSf in the unknown samples are calculated based on the standard curve. Note that higher amounts of TSf in the sample will result in less primary antibody bound to the immobilized antigen on the well, and hence less signal from the secondary antibody. Similar detection methods are used if the binding agent is a non-antibody.
[0195] Sandwich ELISAs and ELISA-like assays are also contemplated. In this case, a first anti-TSf antibody (or a first non-antibody binding agent that binds TSf) is immobilized on a plate, a bead, or another surface, and it is used to capture the TSf in a standard or unknown sample. The first antibody is often polyclonal, but this is not a requirement. Detection of captured material is then accomplished with a second anti-TSf antibody. The second antibody is often monoclonal, but this is not a requirement. As is well-known in the art, the first and second antibodies should not substantially interfere with each other's access to the captured material. Detection can be accomplished with an enzyme-linked antibody specific to the second anti-TSf antibody. Again, if the first (capturing) binding agent and/or the second (detecting) binding agent is a non-antibody, similar methods are used.
[0196] Many variants well-known in the art are contemplated for these competitive and sandwich ELISAs and ELISA-like assays. For example, non-enzymatic methods, such as radioactive, fluorescent, biotin-avidin-based methods, and other methods to detect the anti-TSf antibody are contemplated. Also, automated assays, such as ones performed on a clinical autoanalyzer, are contemplated. Also, various anti-TSf antibodies are contemplated, including but not limited to polyclonal antibodies, monoclonal antibodies, anti-peptide antibodies, antibodies against a TSP fragment present in a cancer patient, antibodies against a TSP fragment generated in vitro, and antibodies against a TSP fragment generated in vitro by proteolysis. Single-chain antibodies are also contemplated, as are non-antibodies.
[0197] For the sandwich ELISA, one option is the use of color-coded microbeads (microspheres) with immobilized anti-TSf antibody to capture, then a fluorescent second anti-TSf antibody to detect. The detection apparatus reads each bead, one at a time, assaying for bead color as well as the signal from the second anti-TSf antibody. The advantage here is that several different analytes can be assayed at once, such as one group of beads for full-length TSP (or an epitope outside of what circulates in substantial concentration in a cancer patient) and another group of beads, of a different color, for a TSP fragment. Or, one group of beads to assay an epitope present in the ˜85-kDa TSP fragment that is not present in the ˜50- or ˜30-kDa fragments, and another group of beads to assay an epitope present in the ˜50-kDa fragment but not the ˜30-kDa fragment (this is followed by a numerical calculation to yield the amounts of ˜85-kDa fragment and of ˜50-kDa fragment separately). An example of this use of color-coded beads can be found at http://www.lincoresearch.com/lincoplex/technology.htm, the web site for Linco Research, Inc.
[0198] Another option for analyzing multiple analytes is SearchLight™ Proteome Arrays, which are multiplexed sandwich ELISAs, currently adapted for the quantitative measurement of two to 16 proteins per well. It is understood herein that the method can also be used for protein fragments, such as one or more thrombospondin fragments. Using a spotting technique, 2 to 16 target-specific antibodies are bound to each well of a microplate, although it is understood that this number can be expanded with improved spotting techniques and/or larger wells. Following a standard sandwich ELISA procedure, luminescent signals are imaged with a cooled CCD (charged coupled device) camera. The image is then analyzed using Array Vision™ software. The amount of signal generated at each spot is related to the amount of target protein in the original standard or sample. Values for specific proteins and/or protein fragments can be calculated based on the position of the spots and comparison of density values for unknowns to density values for known standards (and TSP fragments or peptides can be used as standards). The SearchLight™ technology is available through Pierce Boston Technology Center (http://www.searchlightonline.com/), including customized arrays using proprietary reagents from outside Pierce or assay targets not currently available at Pierce (see http://www.searchlightonline.com/custom_array.cfm).
[0199] Other assay methods are also contemplated. They include but are not limited to immunoblotting, dot-blotting and inmiunoturbidimetric assays (for a detailed example of this last approach with another plasma protein, see Levine, D. M. and Williams, K. J.: Automated measurement of mouse apolipoprotein B: convenient screening tool for mouse models of atherosclerosis. Clin. Chem. 43:669-674, 1997), as well as blotting and/or turbidimetric assays that use binding agents in general. Other competitive assays are also contemplated, such as ones in which material in a standard and an unknown competes with one or more labeled peptides, one or more labeled TSP fragments, and/or labeled TSP for binding to an agent that binds TSf, such as an anti-TSf antibody (the label is then used for detection and hence quantification). One example of this approach is to immobilize an anti-TSf antibody, and then add sample mixed with labeled peptide, labeled TSP fragments, or labeled TSP, so that sample and labeled material compete for binding to the immobilized antibody (note that this approach requires only one anti-TSf antibody). Binding of labeled material is then quantified. It is understood that any of these assays, including immune-based and non-immune-based assays, can be automated. It is also understood that potentially interfering substances in unknown samples can be diluted, removed, inhibited, avoided (for example, in the case of fibrinogen, by using epitopes away from a fibrinogen-binding region of TSP), and/or compensated for.
Use of Thrombospondin Fragments as Immunogens to Generate Fragment-Specific Antibodies:
[0200] A purified preparation of fragments (e.g., by elution of fragments from the gel, by immunoprecipitation or antibody column or other immune-based purification methods, by recombinant DNA techniques, by chemical synthesis, or by a combination of synthesis and/or purification methods) is injected into a rabbit or rabbits with any of the standard adjuvants used with peptide immunogens and antibodies are collected using protocols well known in the art. For small peptides, linkage to a carrier, such as keyhole limpet hemocyanin or bovine serum albumin, is well-known in the art. Injection into other animals is also well-known, including but not limited to a goat, sheep, chicken, turkey, donkey, dog, cat, rat, and mouse. Monoclonal antibodies can be prepared using antibody-producing cells obtained from any immunized animal, but the technology is most easily available for the mouse (for example, antibody-producing cells from an immunized animal are fused with an immortal cell, then clones of fused cells are screened for their production of antibody against one or more thrombospondin fragments of interest).
[0201] It is understood that the methods disclosed herein are readily applied to other members of the thrombospondin gene family, including but not limited to TSP-2 (for a description of the thrombospondin gene family, see The Thrombospondin Gene Family by J C Adams, R P Tucker, & J Lawler, Springer-Verlag: New York, 1995; de Fraipont F et al. Trends Mol. Med., 7:401-407, 2001; and elsewhere). It is also understood that the methods disclosed herein are readily applied to other animal species of economic and/or emotional importance, including but not limited to pets, animals used in breeding, racehorses, and racing dogs.
Examples
Western Blot Analysis of Plasma Samples from Cancer Patients
[0202] Electrophoresis was done according to the Standard Gel Electrophoresis Protocol described above.
[0203] Table I shows plasma and serum samples obtained for analysis.
[0000]
TABLE 1
Sample
Plasma/Serum
Cancer
Stage/Grade
Age/Sex
Comment
A
plasma
colon T2
I/G2
57/F
Ascending
B
plasma
colon T3
II/G2
71/M
Ascending
C
plasma
prostate
II/Gleason 6
71/M
DRE-abnormal
D
plasma
prostate
II/Gleason 5
63/M
DRE-abnormal
E
plasma
lung T2
IB/G2
67/M
Squamous
F
serum
TSP is released from
platelets during clotting,
and proteases are
activated during clotting.
G
plasma
no cancer
N/A
F
lichen planus, a non-
cancerous inflammatory
disorder
[0204] The results are shown in FIGS. 2 and 3 , and the quantitative data are summarized in Table 2.
[0000]
TABLE 2
Quantitation of thrombospondin fragments, normalized for sample
loading Numbers refer to the strengths of TSf signal from the
Western blot (FIG. 3), normalized to the albumin signal from
Coomassie staining (FIG. 2 and final row of numbers in this
Table). Percentages indicate the ratio to the no-cancer sample
(sample G).
Approx MW
A
B
C
D
E
F
G
(kDa)
Colon-1
Colon-2
Prostate-1
Prostate-2
Lung
Serum
No cancer
85
0.572
0.847
1.175
1.292
1.142
1.434
0.526
108.8%
161.1%
223.6%
245.7%
217.4%
272.9%
100.0%
50
0.534
0.666
1.037
1.416
1.809
2.722
0.596
89.7%
111.8%
174.0%
237.7%
303.6%
456.9%
100.0%
30
1.210
1.401
1.687
1.593
1.988
7.351
1.424
85.0%
98.4%
118.5%
111.9%
139.6%
516.3%
100.0%
Total Ab4
2.316
2.914
3.898
4.301
4.939
11.507
2.545
signal
91.0%
114.5%
153.2%
169.0%
194.1%
452.1%
100.0%
Albumin signal
24020
26723
25187
27073
23888
4359
26110
above bkg
[0205] The results summarized in Table 2 represent data generated by densitometric scanning of the photographic film generated by fluorescent staining of the TSP Ab-4 Western Blot (See FIG. 3 ). Thus, for very dark signals, such as the band or group of bands around 30 kDa, the fact that the signals on film saturate when very strong means that increases compared to the no-cancer control sample are seriously under-estimated. This is not particularly evident in the serum sample, which served as the positive control for increased signal, owing to platelet activation (much less serum was loaded, as is evident from the albumin signal; so even though it generated a strong normalized signal, it did not saturate the film nearly as much).
[0206] To obtain the data for Table 2, the signal (above background) for the Western Blot was determined and that signal was normalized to the albumin signal (above background) for the gel shown in FIG. 2 . Table 2 shows the normalized signal (e.g., 0.572) with the percentage (e.g., 108.8%) underneath the normalized signal being the percentage of the “no-cancer” signal.
[0207] The molecular weight standards used were 184 kDa, 121 kDa, 86 kDa, 67 kDa, 52 kDa, 40 kDa, 28 kDa, and 22 kDa. Based on the given molecular weights and the relative positions of the standard bands versus the TSP Ab-4 bands and groups of bands, it was concluded that the TSP Ab-4 signals were in three general bands or groups of bands, at approximately 85, 50, and 30 kDa (see FIG. 3 ). Notice, for example, the relative strength of signals at around 185 kDa (thrombospondin) versus around 85, 50, and 30 kDa (fragments). It is clear that there is overwhelmingly more signal from the fragments than from thrombospondin itself. Thus, detection of specific fragments, as disclosed in the current inventions, is preferred over detection of the TSP molecule itself, or general detection of epitopes that occur throughout the whole TSP molecule, or detection of epitopes outside of those contained within the specific fragments demonstrated herein.
[0208] The plasma samples from cancer patients (lanes A-E) came from Golden West Biologicals, Inc. of Temecula, Calif. The serum sample (lane F) was from a non-cancerous individual. The no-cancer control plasma (lane G) came from an individual with lichen planus, a non-cancerous but inflammatory skin condition.
[0209] The serum sample (Lane F) was prepared by deliberately clotting the blood. Protease inhibitors were not added to sample F until after clotting had been completed and the serum had been harvested. Ideally for the current invention, however, blood is not allowed to clot during sample collection (activation of platelets during clotting causes release of thrombospondin, which was used here on purpose to increase the signal from sample F), and protease inhibitors are added promptly during sample collection (not done for sample F because the clotting cascade involves activation of proteases).
[0210] The predominance of thrombospondin fragments, as opposed to thrombospondin itself, in sample F is consistent with a) platelet activation and release of thrombospondin, plus b) activation of proteases of the clotting cascade, which evidently cleaved the newly released thrombospondin.
[0211] Plasma samples from Golden West Biologicals were samples from individuals with relatively early disease. The first colon cancer sample (lane A) was from an individual with stage I, grade G2 disease. All other cancer samples (lanes B-E) came from individuals with stage II disease (except for lane E, which was stage IB). Plasma from patients with such relatively early stage cancers would be expected to have a lower concentration of thrombospondin fragments than plasma from patients with more advanced cancers. Nevertheless, the robustness of the technique is demonstrated by the fact that (1) increased levels were found with the earlier stage cancers, and (2) gel scanning was done under conditions in which portions of the detecting film were saturated or nearly saturated.
[0212] All cancer samples show an increased signal from the 85-kDa band (or group of similarly electrophoresing bands). All but the stage I sample show increased signal from the 50-kDa band (or group of bands), as well as increased total Ab-4 signal. All but the two early colon cancer samples show increased signal from the 30-kDa band (or group of bands). Thus, the detection and quantitation of specific thrombospondin fragments works to distinguish even relatively early cancer patients from a no-cancer control who has a non-cancerous disease. These thrombospondin fragments are well-suited for diagnostic assays because (a) they have specific molecular weights (or molecular weight ranges); and (b) they contain specific epitopes. The present results provide validation for other fragment-based approaches, including (but not limited to) non-competitive ELISA and ELISA-like assays, and competition assays.
[0213] FIG. 4 shows the results of an independent gel analysis of the samples. The samples were denatured then run on a 12% gel, transblotted, and then stained with the same TSP Ab-4 that we used before. Unlike the blot shown in FIG. 3 , the denaturation step here included urea, and detection used an enzymatic colorometric method that is based on horseradish peroxidase conjugates and the BioRad Opti-4CN substrate kit (see http://www.discover.bio-rad.com/), not fluorescence as before. Along the left edge of lane 1, there are from top to bottom, the following handwritten numbers evident: 1, 97, 66, 45, 30, 20, and 14, respectively. With the exception of 1, the numbers correspond to the positions where standard proteins of corresponding molecular weights (in kDa) had electrophoresed.
[0214] In FIG. 4 , Lanes 2 through 6 correspond to patients A though E, respectively, in Table 1. Lanes 1 and 7 through 9 show the electrophoresis patterns of thrombospondin. The results confirm that:
[0215] a) there is virtually no TSP in the plasma samples (the first plasma lane shows some TSP at its appropriate monomer molecular weight, but this is certainly spill-over from the vastly overloaded first sample lane);
[0216] b) there are indeed TSP fragments in the plasma samples; and
[0217] c) the fragments have molecular weights of about 28, 50, and a faint band around 90 kDa. In this blot, the TSf bands are very sharp, implying well-defined molecular weight fragments (presumably a purely technical improvement, owing to better denaturation in the presence of urea). As in FIG. 3 , there are a number of less prominent fragment bands at other molecular weights. It is understood that a thrombospondin fragment in any of these bands can also be assayed and used in diagnosis and screening and in kits. | The invention relates to thrombospondin fragments found in plasma, their use or use of portions thereof in diagnostic methods, as method calibrators, method indicators, and as immunogens, and as analytes for methods with substantial clinical utility; and their detection in plasma or other bodily fluids for purpose of diagnostic methods, especially for cancer. | 8 |
FIELD
[0001] The present method was developed to service high temperature wells without requiring them to be cooled prior to servicing.
BACKGROUND
[0002] There are currently a number of energy companies producing oil in Northern Alberta regions using steam-assisted gravity drainage (SAGD) recovery methods. As its name implies, SAGD production uses steam to elevate the temperature of the bitumen or heavy crude in the formation. Once the viscosity is reduced to a sufficient level, the fluids will freely flow, by gravity, to the well where they can be pumped to the surface. Temperatures typically encountered in SAGD operations are generally between 200° C. and 300° C. and pressures are generally between 2000 kPa 5500 kPa. Other wells aside from SAGD wells may also operate under similar high temperature and high pressure conditions. For example, with the toe heel air injection method (THAI) of producing bitumen, the temperature may be in excess of 600° C.
[0003] Conventional well servicing operations require that both the well temperature and the well bore pressure are reduced before work can proceed. In SAGD wells, the temperature of a particular well is reduced by shutting down the steam injection in the vicinity of the well to be worked over. Of course, once the steam is shut down, production in all of the neighbouring wells ceases until the reservoir temperature gets back up to producible levels. This is a lengthy process and it may end up being several months until the well is back in production. There are, therefore, considerable costs incurred with a well servicing operation; the cost of reheating the formation to producible levels as well as the loss of production during this period. In some cases, a number of wells are positioned in close vicinity to one another so as to support each other in heating the formation. In the event that one of these wells require servicing a number of wells could be affected by the prerequisite to cool one of the group's members. Again, several months of seriously impacted production could result; not to just one well, but to numerous wells.
[0004] What is required is a method to safely perform servicing operations on high temperature wells while they are operating within their normal temperatures and pressure ranges.
SUMMARY
[0005] There is provided a method of servicing high temperature wells, comprising the steps of securing a cooling chamber onto a wellhead of a high temperature well; raising a tubular member from the high temperature well into the cooling chamber; and injecting the cooling chamber with a cooling fluid to cool the hot tubing string prior to handling.
[0006] According to different aspects, the cooling chamber is defined by a stack of spools attached in end to end relation onto the wellhead. The tubular member may have a temperature of at least 100° C. or 200° C. prior to entering the cooling chamber. The tubular member may be cooled to a temperature of less than 50 ° C. in the cooling chamber. The tubular member may be continuously raised through the cooling chamber. The tubular member may be raised during a snubbing operation. The cooling chamber may have a cooling fluid input and a cooling fluid output for circulating cooling fluid through the cooling chamber. Injecting the cooling fluid may comprise maintaining the pressure of the cooling fluid in the cooling chamber at a pressure that avoids overbalancing the well. The cooling fluid may be in direct contact with the tubular member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] These and other features will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to be in any way limiting, wherein:
[0008] FIG. 1 is a side elevation view of a wellhead with a stack of spools forming a cooling chamber.
[0009] FIG. 2 is a top plan view in section of the cooling chamber.
DETAILED DESCRIPTION
[0010] The method will now be described with reference to FIGS. 1 and 2 .
[0011] It is possible to maintain pressure and work on the well by cooling the tubular member, such as a tubing string or coiled tubing string, and pulling the tubular member through a closed BOP. The tubular member is cooled by a cool fluid or gas being pumped through a cooling chamber situated between the wellhead and the snubbing unit. For the purposes of this application, it will be understood that “fluid” means any substance, such as a liquid or gas, that can flow. For the purposes of this application, a high temperature well is considered anything with a temperature above that which can be safely handled by workers, such as 50° C. However, the method is designed primarily for use with high temperature wells that have a temperature of at least 200° C.
[0012] Referring to the embodiment depicted in FIG. 1 , a SAGD well 10 is shown with a number of spools 12 bolted onto the wellhead 14 . Referring to FIG. 2 , spools 12 have an internal diameter that forms a cooling chamber 15 . The cooling chamber 15 is large enough to receive the tubular body 16 as it is pulled through. While spools 12 are shown, it will be understood that other bodies could be used to form the cooling chamber, such as a large pipe, or other body that is large enough and has a cavity. Referring again to FIG. 1 , the spools 12 are stacked end to end and allow the tubing string to pass through their centers. The height of the spool stack is determined by the amount of cooling required to bring the tubing string down to a temperature that can be handled safely. For example, temperatures above 50° C. are likely too hot to safely handle by workers. If more cooling is required to reach a safe operating temperature, more spools 12 may be stacked together give a larger area of tubing exposed to the cooling fluid or gas.
[0013] Above the stack of spools 12 is a snubbing unit 18 . The snubbing unit blow out preventer stack 20 is bolted to the top most spool and keeps the pressure in the well from escaping to the atmosphere. The snubbing unit 18 provides a means of raising or lowering the tubing string in and out of the well while it is under pressure.
[0014] On each of the lowermost and uppermost spools 12 , there is a port 22 so that a suitable gas or liquid can be pumped into the cooling chamber. The fluid is pumped into one port 22 , flows up or down the stack of spools and out of the other port 22 . The pressure is maintained on the outgoing line so that the fluid pressure in the spool stack is equal to or higher than the well pressure. This prevents the fluid from escaping down the well. The fluid enters into the spool system at a lower temperature than the tubing string and serves to cool it as it passes through the stack of spools. A number of variables can be adjusted to change the amount of cooling—the fluid used, the temperature of the fluid, the height of the spool stack, the speed at which the tubing string is pulled through the spool stack 12 , and the flow rate of the fluid. By this means, tubing can be cooled as it is removed from the well by the snubbing unit 18 . The pressure is maintained by the BOP system 20 and the well can be serviced without having to cool the well down. As the hot tubing string is extracted through the wellhead 14 , it is exposed to the flow of cooling gas in the spool stack. The extraction rate of the tubing as well as other variables can be adjusted so that the tubing string comes out of the BOP 20 at a temperature that can be safely handled by the personnel on the snubbing unit.
[0015] In a preferred embodiment, the removal of production tubing results in intermittent movement of the tubing string as the various lengths are removed. Preferably, the cooling occurs quickly enough that the tubing string is cooled as it is pulled up through spools 12 . This is particularly important if used with coiled tubing string, as it is pulled continuously.
[0016] In the depicted embodiment, the cooling chamber is open to the annulus of the well. In a preferred embodiment, a gas, such as nitrogen gas, may be pumped into the cooling chamber at the bottom port 22 , and extracted at the top port. The nitrogen gas is pumped in at a pressure that is slightly higher than the wellbore pressure, and is allowed to escape through the top port 22 . This creates a nitrogen gas buffer at the top of the wellbore. While there will generally be some gas that escapes downhole because of the higher pressure and the mixing of fluids, the rate of flow in and out of the cooling chamber may be monitored to ensure that this is minimized to an acceptable level. If it is found that an unacceptable gas is being diverted downhole, the pressure may be adjusted to reduce this. Other gases may be used, such as carbon dioxide, although nitrogen is preferred for economic reasons. For safety reasons, the gas should be an inert gas. While the fluid may be at any temperature below the target temperature, a colder fluid will accelerate the cooling process. However, excessively cold temperatures may cause certain components to freeze. To balance these concerns, a suitable temperature for the cooling fluid has been found to be within 3 or 4 degrees of 5° C.
[0017] In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.
[0018] The following claims are to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, and what can be obviously substituted. Those skilled in the art will appreciate that various adaptations and modifications of the described embodiments can be configured without departing from the scope of the claims. The illustrated embodiments have been set forth only as examples and should not be taken as limiting the invention. It is to be understood that, within the scope of the following claims, the invention may be practiced other than as specifically illustrated and described. | A method of servicing high temperature wells. A cooling chamber is secured in end to onto a wellhead of a high temperature well. A hot tubing string is raised from the high temperature well into the cooling chamber. A cooling fluid is injected into the cooling chamber to cool the hot tubing string prior to handling. | 4 |
PRIORITY
This application is a continuation of U.S. patent application Ser. No. 14/285,786, filed May 23, 2014 (now U.S. Pat. No. 9,038,334), which in turn is a continuation of U.S. patent application Ser. No. 13/653,007, filed Oct. 16, 2012 (the '007 application, and now U.S. Pat. No. 8,745,939). The '007 application is a divisional application of U.S. patent application Ser. No. 11/584,328, filed on Oct. 18, 2006 (now U.S. Pat. No. 8,302,353), which in turn is a continuation-in-part of U.S. patent application Ser. No. 11/251,221, filed on Oct. 14, 2005, which in turn claimed the benefit of U.S. Provisional Application No. 60/619,343, filed on Oct. 15, 2004.
FIELD OF THE INVENTION
The present invention relates to the field of building construction. More particularly, the present invention provides a method and apparatus that prevents water intrusion into the walls of the building around a window, door, or other framed object.
BACKGROUND OF THE INVENTION
A typical window 100 of the prior art is shown in FIG. 1 . The window 100 may include one or more panes of glass 110 , which may be embedded in a single sash, or in an upper and lower sash such as in a double-hung window. The sash is secured in a frame 120 , which consists of two side jambs 130 , a top jamb 140 , and a sill 150 . The window frame 120 is typically made from wood, vinyl, aluminum, or fiberglass, but may be made from any durable, rigid material.
Typically, a window is installed into a rough opening 200 in a house or building, as shown in FIG. 2 . The rough opening 200 forms a window cavity 202 surrounded by a header 210 , two sides 220 , and a sill 230 . The header 210 must be constructed sufficiently sturdy to support the necessary roof loads, since these loads cannot be supported by the window unit 100 . This is especially important with large window units 100 , or when a “window wall” is created with multiple windows side-by-side. The rough opening 200 has an interior side 240 and an exterior side 250 relative to the building itself. The sill 230 is sloped toward the exterior side 250 to allow water that makes its way to the sill 230 to drain out the exterior of the building. The height and width of the window cavity 202 is constructed larger than the height and width of the window frame 120 ; typically about three-quarters of an inch (approximately two centimeters) larger in each direction. This leaves an approximately three-eighth inch space (about one centimeter) between the window 100 and the rough opening 200 on each of the four exterior faces 160 (the top 120 , sill 150 , and both sides 130 ) of the window 100 .
To hold the window unit 100 in place, the unit 100 is generally constructed with a nailing or installation flange 170 near the exterior edge on each of the four faces 160 of the window frame 120 . FIG. 3 shows the window 100 of FIG. 1 sectioned along line 3 - 3 , and shows the relationship of the nailing flange 170 versus the rest of the window frame 120 and the glass 110 . FIG. 4 shows the same section of window 100 , this time with the nailing flange 170 being used to secure the window frame 120 to one of the sides 220 of the rough opening 200 . The window 100 is installed so that the nailing flange 170 is on the building exterior 250 . Nails 300 are then placed through both the flange 170 and the side 220 of the rough opening 200 . These nails 300 are used around the circumference of the window 100 , preferably centering the window 100 in the opening 200 .
Because the opening 200 is deliberately sized larger than the window 100 , a space 310 is created between the opening 200 and the window. Modern construction techniques involve creating a vapor barrier between warm moist air inside a house and the outside, cooler air. To complete the vapor barrier, it is necessary to extend the vapor barrier from the rough opening 200 of the house framing to the window 100 itself. To accomplish this, foam 320 is inserted into space 310 around all four faces 160 of window 100 . This foam 320 also serves to insulate this gap 310 . Most window manufacturers carefully advise the window installers to take steps to prevent the expanding foam 320 from warping the window frame 120 . In most cases, installers are instructed to use low expanding foam 320 . In addition, installers are instructed to begin inserting the foam 320 at the nailing flange 170 , but to avoid filling the entire space 310 all the way to the interior 240 of the rough opening 200 and window frame 120 . This should allow the expansion of the foam 320 within space 310 without warping the window frame 120 .
To prevent water leakage under the nailing flange 170 , installers will generally place a sealant between the flange 170 and the exterior surface 250 of the rough opening 200 . Sill flashing is used on the sill 230 to provide a moisture barrier to prevent water that enters the window cavity 202 after installation of the window 100 from entering the wall under the sill 230 . Moisture in the window opening 202 will ideally pool on the sill flashing, where it will generally drain down the non-wood side of the exterior building paper. Any moisture that does not drain off the sill will remain on the sill flashing until it evaporates. Because of this, it is generally encouraged that sealant not be used on the bottom or sill nailing flange 170 , in order to allow for drainage and evaporation from outside.
Unfortunately, this prior art technique of window construction and installation has caused various moisture and mold problems in today's buildings. What is needed is an improved construction and installation method for windows the does not cause these problems.
SUMMARY OF THE INVENTION
The present invention prevents moisture that enters the window opening from entering the interior of the building by creating a channel behind the nailing flange of the window. Prior art windows and techniques encouraged foam insulation to be inserted between the window and the rough opening all the way to the nailing flange that is used to secure the window. This insulation prevented moisture from reaching the sill, from which it could drain or evaporate. Instead, the foam directed the water into the interior of the building. Alternatively, water that did reach the sill could become trapped behind the insulation and be prevented from draining or evaporating. In this case, the water may cause rotting inside the framing.
The present invention creates a barrier in the space between the window and the rough opening that prevents the foam from reaching the nailing flange. On the interior side of this barrier, the foam is installed normally. On the exterior side of this barrier a channel is created. This channel preferably runs around the circumference of the window. The channel allows water that enters behind the nailing flange the ability to drain down to the window sill where it can drain or evaporate.
To form the barrier, a gasket can be constructed around the perimeter of the window. This gasket is sized to engage the rough opening, such that it forms a barrier running from the window to the rough opening. Alternatively, the gasket can be sized to extend at least half way into the space between the window and the opening.
The gasket can be attached to the window during window manufacture. Alternatively, the gasket can be sold separately and attached to the window at the installation site. The gasket may also be directly attached to the rough opening itself, where it will then engage the window frame when the window is installed. The gasket can be relatively straight, extending perpendicularly from the window or rough opening and then bending during window installation. Alternatively, the gasket can be curved. The curved gasket can be sized large enough to span a large space between the window and the rough opening, and can be compressed easily to span a much smaller space. If designed to engage the rough opening, the gasket should be flexible so as to bend during the insertion of the window. If actual engagement is not anticipated, the gasket can be rigid. Finally, the barrier can be formed with a disintegrating object that disintegrates once the insulation has be installed, or a wicking object that remains in the channel to block the foam insulation while still allowing water to reach the sill.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a prior art window.
FIG. 2 is a perspective view of a rough opening for a window.
FIG. 3 is a sectional view of a portion of the window of FIG. 1 along line 3 - 3 .
FIG. 4 is a sectional view of the portion of the window shown in FIG. 3 attached to the rough opening of FIG. 2 .
FIG. 5 is a perspective view of a window of the present invention.
FIG. 6 is a sectional view of a portion of the present invention window of FIG. 5 taken along line 6 - 6 .
FIG. 7 is a sectional view of the portion of the present invention window shown in FIG. 6 attached to the rough opening of FIG. 2 .
FIG. 8 is a perspective view of a second embodiment of the present invention detached from a window.
FIG. 9 is a sectional view of the second embodiment being used on a window in a rough opening.
FIG. 10 is a sectional view of a third embodiment of the present invention being used in connection with a window in a rough opening.
FIG. 11 is a sectional view of a fourth embodiment of the present invention in which the gasket has a rounded shape that is easily compressed.
FIG. 12 is a sectional view of a fourth embodiment of the present invention showing a decomposing article being used in connection with a window in a rough opening.
FIG. 13 is a sectional view of the fourth embodiment after the decomposing article has decomposed.
FIG. 14 is a sectional view of a fifth embodiment of the present invention showing the use of a wicking article.
FIG. 15 is a sectional view of a sixth embodiment of the present invention showing the use of a wicking element attached to the nailing flange of the window.
FIG. 16 is a sectional view of the sixth embodiment of FIG. 15 being used in connection with a window in a rough opening.
FIG. 17 is a perspective view of a door frame of the present invention.
FIG. 18 is a sectional view of a seventh embodiment of the present invention being used on a window in a rough opening.
FIG. 19 is a section view showing the length of the seventh embodiment from FIG. 18 .
DETAILED DESCRIPTION OF THE INVENTION
Recognition of the Problem
The inventor of the present invention has discovered a significant problem with prior art windows and installation techniques as illustrated in FIGS. 1, 2, 3 and 4 and described above. As explained above, the current thinking in window and building construction allows moisture that enters the window cavity to drain and evaporate at the sill. For this approach to function adequately, three requirements must be met. The moisture that enters the window cavity 202 must be able to flow down to the sill 230 . The sill 230 must be properly constructed to ensure a waterproof surface. And, the sill must be able to either drain the moisture to the outside 250 of the building, or must have enough ventilation to allow evaporation.
Unfortunately, the construction technique described above does not allow the first requirement to be met. Moisture will often enter into the window cavity 202 at the top 120 and sides 130 of the window 100 . Assuming that there is no failure in the window itself, the moisture enters at these locations under the nailing flange 170 . While the sealant applied under the flange 170 should help prevent this, gaps or cracks in the sealant are inevitable. The moisture that seeps under the nailing flange 170 will enter the space 310 between the window 100 and the rough opening 200 . At this point, the foam 320 that was installed all the way to the nailing flange 170 will interfere with the ability of the moisture to find its way down to the sill 230 . The problem is that the foam material 320 is permitted to fill the space 310 all the way to the nailing flange 170 . At some point, the foam 320 will form a blockage against the nailing flange 170 , and prevent any further downward movement of the moisture toward the sill 230 . In addition, since the foam insulation 320 is never perfectly formed, cracks and gaps in the foam 320 form passageways that permit the water to move toward the interior 240 of the rough opening 200 . In fact, once the foam insulation 320 has formed a blockage with the nailing flange 170 , the only place for the water to go is toward the interior of the building. There the water remains, leading to water damage and molding issues.
First Embodiment of the Solution
The present invention involves a plurality of techniques to ensure that the foam material 320 that is applied from the interior 240 of a building in the space 310 between the window 100 and the rough opening 200 is not allowed to reach the nailing flange 170 . By doing so, a channel or gap is created between the insulation 320 and the flange 170 that allows all moisture that enters anywhere around the edge of the window 100 to drain properly to the sill 230 .
The first such technique is shown in FIG. 5 . There a standard window 100 with a nailing flange 170 has been fitted with a gasket 400 around its circumference. This gasket 400 can be placed on each of the four peripheral faces 160 of the window frame 120 , and is positioned between the nailing flange 170 and the interior surface of the window 100 . While installing the gasket 400 around all four faces 160 of the window 100 is preferred, it is well within the scope of the present invention to install the gasket 400 on less than all of the circumference of the window. For instance, an installer or window manufacturer may refrain from installing the gasket 400 along the sill edge 150 of the window 100 to allow easier drainage at the sill 230 of the opening 200 . However, this is generally not preferred as foam material 320 that reaches the nailing flange 120 at the sill 230 can also prevent proper drainage of moisture. Modern building codes require the foam material 320 to complete the vapor barrier on all sides of a window 100 , and therefore the gasket 400 is preferably used on all sides as well.
As shown in the cross-sectional view in FIG. 6 , gasket 400 projects away from the window frame 120 , but does not extend as far as the nailing flange 170 . The purpose of the gasket 400 is to approach or engage the rough opening 200 when the window 100 is installed. The flexible gasket 400 can be formed and attached to the window frame in a variety of ways. In FIG. 6 , it is shown that the gasket 400 is formed with a tongue 410 that fits into a groove in the window frame 120 . This tongue-and-groove connection is designed to prevent the gasket 400 from moving or otherwise disengaging with the window frame 120 during the installation of the window 100 . Of course, other protrusion and channel combinations could be used equally as well as the tongue and groove shown in FIG. 6 , including protrusions on the window frame 120 that extend into channels or grooves on the gasket 400 .
In a first embodiment, the gasket 400 engages and flexes against the opening 200 when the window 100 is inserted into the window. To help assist the tongue-and-groove fitting in securing the gasket 400 , the gasket 400 is also formed with a base section 420 that abuts the window frame 200 . This base section helps keep the gasket 400 relatively perpendicular vis a vis the exterior surface of the window frame 200 . When designed to engage the opening 200 , it is important to manufacture the gasket 400 out of a significantly flexible material to allow the gasket 400 to bend during insertion.
One advantage of permanently attaching the gasket 400 on the peripheral faces 160 of the window 100 is that the gasket 400 can be added during the construction of the window 100 itself. In this way, the window manufacturer can be responsible for securely attaching the gasket 400 . The window 100 is then delivered to the construction site with the gasket attached, where the window installer can install the window 100 and gasket 400 combination in much the same as any ordinary window 100 . Window manufacturers may use any known technique to attach the gasket 400 to the window 100 , including protrusions and channels, or by nailing or stapling the gasket 400 directly to the window frame 120 . Alternatively, the gasket can be formed as an integral part of the window frame 120 itself.
As shown in FIG. 7 , the gasket 400 of this first embodiment will preferably contact the framing of the rough opening 200 , such as side 220 , thereby dividing the space 310 between the window 100 and the opening 200 in two. The portion of the space 310 closest the interior 240 of the building can be used for the foam material 320 . As the foam 320 is installed, it can be installed all the way up to the gasket 400 . This is similar enough to the prior art technique of installing the foam 320 all the way up to the nailing flange 170 so as to not require any significant change in foam installation techniques.
The other portion of the space 310 divided by the gasket 400 is the gap or channel 500 formed adjacent the nailing flange 170 . Because the gasket 400 is formed on at least the top 140 and sides 130 of the window frame 120 , the formed channel 500 is ensured of existing at these locations as well. In this way, the gasket 400 will allow for any moisture that penetrates the opening around a window 100 to have the proper channel 500 to continue its movement down toward the sill 150 and ultimately out to the exterior 250 of the building. In addition, the gasket 400 itself serves as a barrier to any water or moisture that enters the channel 500 , and helps to prevent that water from entering into the interior or framing of the building.
In this embodiment an entire width of the gasket structure 400 from one side 130 to the other side 130 of the window 100 is slightly larger than that of the largest recommended rough opening 200 , as defined by the window manufacturer. The gasket 400 should also be large enough to account for a non-centered window 100 , so that the gasket 400 will still engage the opening 200 . The gasket 400 should be rigid enough to hold its position in space 310 against insulation 320 , yet be flexible enough to handle a small space 310 that might be created in a non-centered window 100 . The flexibility should also be great enough so as not to hinder the simple installation of a window. In the preferred embodiment, the gasket 400 can be constructed of almost any material that can meet these basic properties, including open or closed cell foam plastics, natural or synthetic rubber, or the like. If a rigid gasket 400 is to be used, the choice of materials would be even broader, including wood, metal, and hard plastics.
FIG. 8 shows a second embodiment of the present invention gasket 410 . This gasket 410 can be manufactured in one piece and sized for a particular window 100 . The gasket 410 can then be applied to the window 100 at the installation site. Preferably, the gasket 400 is applied over the window frame 120 from the interior side. As shown in the cross-sectional view in FIG. 9 , the window 100 can be formed with a groove 412 for receiving the gasket 410 . Once the gasket 410 is installed in the groove 412 , it can either be nailed or stapled in place by the installer, or the elasticity of the gasket 410 can be relied to keep it in place. When installed, this second embodiment of the gasket 410 functions similar to gasket 400 , as can be seen by comparing FIG. 9 with FIG. 7 .
Alternatively, a gasket 420 can be created that is designed to be installed directly onto the rough opening 200 , as shown in FIG. 10 . In this Figure, the gasket 420 has been nailed to the opening 200 with a plurality of nails 422 , only one of which is shown in FIG. 10 . Alternatively, gasket 420 can be attached with staples or adhesive to the opening 200 . This gasket 420 can be provided to window installers in strips, which can then be cut to the size of the opening 200 . Once the gasket 420 has been attached to the opening, the window 100 can be inserted. The frame 120 of the window 100 will then engage the gasket 420 , much like how the rough opening 200 engaged gaskets 410 and 400 during the window insertion process described above. Like the other embodiments 410 , 400 , gasket 420 functions by forming a gap or channel 500 for the drainage of moisture and water. The gasket 420 further functions to prevent water from entering the interior of the house, and serves to prevent the insulation 320 from impeding the flow of moisture in the channel 500 .
FIG. 11 shows another embodiment of a gasket 430 that can be used to create channel 500 . In this case, the gasket 430 has a rounded shape that is easily compressed. This allows the gasket to fill a relatively large space 310 between the window and the rough opening 200 , while still being able to easily be compressed for a smaller space 310 . This shape is called rounded in this invention description, and is defined by having a gasket that forms at least 270 degrees of a complete circle.
FIG. 12 shows a fifth embodiment, in which a decomposing object 440 is placed adjacent to the nailing flange 170 after the window 100 is installed in the rough opening 200 . This object 440 has an interior face 442 , which servers to block the foam 320 from abutting the nailing flange 170 when the foam material 320 is injected into the space 310 between the window 100 and the rough opening 200 . To form channel 500 , the object 440 will then disintegrate, leaving only the channel 500 , as is shown in FIG. 13 . Such an object 440 can be created using an inflatable balloon. The balloon can be inserted into the space 310 either already inflated or deflated (which is then inflated in place). The size of the balloon will easily conform to the shape of the space 310 , and can be pressed to abut the nailing flange 170 . When the insulation 320 is injected into space 310 , the interior face 442 of the balloon 440 will prevent the foam 320 from reaching the nailing flange 170 . When the foam insulation 320 has firmed up, the balloon can be deflated using a long thin pin inserted through the insulation 320 . Alternatively, the balloon 440 can be design to deflate over time. Furthermore, a portion of the balloon 440 can be secured to the header 210 to prevent the deflated balloon from interfering with water flow in the channel 500 . Other disintegrating objects 440 can be used, either now known or hereinafter developed. Ideally, the disintegrating object 440 will have an interior face 442 that can impede the flow of injected insulation 320 , and will disintegrate completely soon after the insulation 320 has firmed or solidified.
Another embodiment of the present invention is to replace the disintegrating object 440 with a wicking object 450 , as shown in FIG. 14 . The wicking object would be placed in space 310 , and would impede the flow of the insulation 320 at face 452 , just like the disintegrating object 440 shown in FIG. 12 . However, the wicking object would not disintegrate after the foam 320 is installed, but would be designed to wick moisture around the window frame 120 toward the sill 230 of the rough opening 200 . In effect, the entire channel 500 would remain, but would stay filled with the wicking object 450 . The wicking object 450 would not impede the flow of moisture to the sill 230 , but would help wick the moisture to the sill 230 . The wicking object 450 could be made of a material that conveys the moisture via capillary action. Alternatively, the wicking object 450 could be formed of any material that would allow the flow of water while impeding the flow of foam 320 . For instance, the wicking object 450 could be formed of a porous, fibrous material that does not use capillary action but does allow water flow. One example of such a material is the Home Slicker® product sold by Benjamin Obdyke Incorporated, Horsham, Pa. Alternatively, traditional fiberglass insulation can be used since water is not absorbed by the glass fibers found in fiberglass insulation. Water that enters channel 500 would flow through the fiberglass fibers 450 down to the sill 230 .
FIG. 15 shows a sixth embodiment of the present invention in which a wicking strip 460 is attached directly to the window frame 120 . In the preferred embodiment, the wicking strip 460 abuts against both the nailing flange 170 and the main portion of the window frame 120 . Alternatively, the wicking strip 460 could be attached to only one of these portions 120 , 170 of the window 100 , so long as the strip 460 is positioned near both the nailing flange 170 and the window frame 120 . This wicking strip 460 will allow moisture to pass through it while impeding the progress of foam 320 , as shown in FIG. 16 . Notice that the strip 460 in FIG. 16 is not attached directly to the nailing flange 170 . The wicking strip 460 acts to stop the foam 320 at face 462 while partially filling gap 500 . As with the wicking object 450 that is positioned in the gap 500 , the wicking strip 460 that is pre-attached to the window 100 can move water through capillary action or by being a porous material that allows water to pass through. The moisture that enters gap 500 can flow down through the unfilled portion of the gap 500 or through the wicking strip 460 of the window frame 120 . The wicking strip 460 should be sized so as to position the barrier face 462 at a sufficient distance from the nailing flange so as to prevent the foam 320 from reaching the nailing flange 170 even when a portion of the gap 500 is not filled by the wicking strip 460 .
The present invention is not limited to window frames 120 , but would be equally applicable to any framed item that is inserted into an opening of a building. For instance, FIG. 17 shows a door 600 having a door frame 602 . This door 600 is also fitted with a nailing flange 604 , although such a flange would not be necessary for this invention. The gasket 470 of the present invention is attached to the periphery of the door frame 602 , preferably at least on the top and side of the door frame. This gasket 470 would function similar to the barriers 400 - 460 described above.
FIG. 18 shows yet another embodiment of the present invention in gasket 480 . As shown in this figure, gasket 480 does not completely extend from window 100 to frame 200 . Nonetheless, the gasket 480 serves as a sufficient barrier to foam material 320 so as to create the same gap 500 as was created in the other embodiments. In this case, the foam material 320 extends somewhat into the gap, but not significantly. The foam material 320 would be considered to extend significantly into the gap if the foam 320 came into contact with the nailing flange 170 . When the gasket 480 does not engage another surface, it is possible for the gasket 480 to be constructed of a rigid material. Preferably, this gasket 480 will extend at least half way across the space between the window 100 and the frame 200 .
Window frames 120 may be completely smooth on their exterior jamb surfaces, or they may have minor bumps and ridges 122 as shown in FIG. 19 . These irregularities 122 on the relatively planar 124 face of the window frame 120 do not significantly impede the flow of foam 320 that is inserted into gap 310 between the roughed opening 200 and the window frame 120 . To impede the foam 320 and serve as a barrier as described above, the barrier 480 should extend significantly into the gap 310 , which is not the case with irregularities 122 . Typically, window manufacturers require a minimum one-quarter to three-eighth of an inch between the window frame 120 and the roughed opening 200 . Because this distance might be greater, it is preferred that the barrier 480 extend away from the generally planar face 124 of the window frame by a distance 482 approximately equal to this minimum distance. Consequently, one way of measuring the size of the barrier 480 of the present invention is by this distance 482 , which ideally is at least 0.20 inches.
The many features and advantages of the invention are apparent from the above description. Numerous modifications and variations will readily occur to those skilled in the art. Since such modifications are possible, the invention is not to be limited to the exact construction and operation illustrated and described. Rather, the present invention should be limited only by the following claims. | A method and device are presented that creates a channel adjacent a nailing flange of a window in between the window and the rough opening that receives the window. The channel is created by establishing a barrier that prevents foam insulation inserted into the space between the window and the rough opening from reaching the nailing flange. The channel then ensures proper drainage of water that enters the window cavity down to the window sill. A gasket is presented that can be attached to the window or the rough opening to create the barrier. Alternatively, a disintegrating object or a wicking object can be used to impede the flow of insulation foam and to create the appropriate channel. The present invention is equally applicable to doors or other framed objects received into the exterior shell of a building. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority from Provisional U.S. Patent Application Ser. No. 60/068850, filed Dec. 29, 1997 and incorporated herein by reference.
STATEMENT OF GOVERNMENT INTEREST
The subject matter of the present application was developed using government funds. The U.S. Government, if not owner of the present invention, has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms.
FIELD OF THE INVENTION
The present invention relates to a computer system and network and radar system for autonomously and continuously generating cloud radar data, storing such radar data, and distributing the radar data over a network. The system of the present invention also autonomously controls, calibrates, and monitors the radar system during operation.
BACKGROUND OF THE INVENTION
As part of an effort to study global warming and the effect of greenhouse gases, scientists have undertaken a program of atmospheric radiation measurement (ARM). Part of this study requires measurement of cloud data for a number of locations around the planet. In the prior art, it would be necessary to have a technician or technicians on duty at remote locations to take such data at particular given times, and store such data for further analysis. Such techniques are cumbersome and expensive, as they require a large number of man-hours to operate such equipment at remote locations. Moreover, a scientist or researcher may be interested in cloud data for a particular given time period for which data was not manually taken.
Cloud monitoring may also be of use in airport operations to enhance safety and efficiency in cloudy conditions. Again, however, manpower may not be available to maintain and operate such a radar system and generate cloud radar data upon demand.
SUMMARY OF THE INVENTION
In the present invention, a cloud radar apparatus is mounted on a portable containerized unit, a number of which may be located at various positions throughout the planet.
Cloud radar data from each unit are periodically measured and stored and made available to researchers, upon request, through the Internet or other network. A high water mark program monitors the storage capacity of the system's hard drive and periodically deletes older files. An archive program archives older data files to a digital audio tape (DAT) or the like.
The system comprises two computers operating on different operating systems. Characteristics of each operating system allow each computer to optimally perform its functions. A first computer uses a first operating system which allows it to readily interface with various radar equipment using an IEEE 488 interface or the like, to monitor the health of the equipment and operate the equipment. A second computer system uses a second operating system in a multi-user mode which allows it to readily access and manipulate data files and transfer data over the network.
Communication between the two computers is achieved by allowing the first computer to log into the second computer as one of the multiple users. The first computer may upload data to the second computer using a FTP protocol or the like. A second user in the second computer may generate cloud radar images and apply calibration data to received data to produce calibrated data.
A third user may be logged onto the second computer to handle data transfers to and from the network. By using two computers with operating systems selected for optimum performance with their respective tasks, the system of the present invention allows for completely autonomous operation of a remote radar site with automated collection and distribution of cloud radar data.
BRIEF DESCRIPTIONS OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the major hardware components of the present invention.
FIG. 2 is a block diagram illustrating the communication paths between different RP processes within Radar Processor (RP) 118.
FIG. 3 is a block diagram illustrating the sequence of steps in the file transfer.
FIG. 4 is a block diagram illustrating the relationship between multi-users on Data Management Processor (DMP) 126 and locations of various data and program files.
FIG. 5 is a block diagram illustrating the relationship between program s and files in Data Management Processor (DMP) 126 calibration extraction sequence.
FIG. 6 is a block diagram illustrating the relationship between programs and files in the calibration routine of Data Management Processor (DMP) 126.
FIG. 7 is a block diagram illustrating the steps performed by Radar Processor (RP) 118 in calibrating the radar system and generating radar calibration files.
FIG. 8 represents an image for cloud radar data generated at the Department of Energy's Southern Great Plains (SGP) site for Feb. 17, 1998, representing reflectivity for a predetermined sequence of radar pulses.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram illustrating the major hardware components of the present invention. The hardware comprises a radar wind profiler (RWP) system comprising commercial off the shelf (COTS) components. High gain antenna 102 may comprise, for example, antenna Model No. 63208300 manufactured by Alpha Industries Inc. of Woburn, Mass. Antenna 102 may be mounted on the roof of a weatherproof climate controlled enclosure similar to a cargo container. Containerizing the hardware allows multiple systems to be rapidly and readily deployed at different points throughout the planet.
Circulator 104 receives signals from and outputs signals to high gain antenna 102. Circulator 104 may comprise, for example, a Model No. WJR-NC circulator manufactured by Microwave Resources Inc. of Chino, Calif. Traveling Wave Tube Amplifier (TWTA) 110 amplifies the output signal for output to high gain antenna 102 through circulator 104. Traveling Wave Tube Amplifier (TWTA) 110 may comprise, for example, a Model No. 187Ka amplifier manufactured by Applied System Engineering of Fort Worth, Tex.
Receiver protection switch 105 protects the receiver portion of the system from input spikes and the like while filtering out spurious noise. Receiver protection switch 105 may comprise, for example, a Model No. 570A-SY T/R switch manufactured by EMS Technologies of Atlanta, Ga. Receiver protection switch 105 may be supplied power through switch 134 through calibration noise diode 132 and RF variable attenuator 130. RF attenuator 130 may comprise, for example, a Model No. FVA-25 RF Attenuator manufactured by Microwave Resources Inc. of Chino, Calif. Calibration Noise Diode 132 may comprise a Model No. NC 53281 34.86 manufactured by Noise Comm, Inc. of Paramus, N.J.
The output of receiver protection switch 105 passes through low noise amplifier (LNA) 106 which may comprise, for example, a Model No. DB94-0880 manufactured by DBS Microwave Inc. of El Dorado Hills, Calif. The output of LNA 106 passes to RF Coherent Up/Down Converter 108 which may comprise, for example, a model R.06-35-.06 converter manufactured by Spacek Labs Inc. of Santa Barbara, Calif. RF coherent up/down converter converts output signals from an intermediate frequency (IF) to a 34.86 GHz RF signal and received signals from high gain antenna 102 back to IF.
IF modulator/receiver chassis 112 may comprise, for example, a model 60001046 receiver/modulator manufactured by Radian International, LLC of Boulder, Colo. IF modulator/receiver 112 modulates an IF signal for output to RF coherent up/down converter 108 and receives an IF return signal from RF coherent up/down converter 108. Interface chassis 114 may comprise, for example, a Model No. 60001047 manufactured by Radian International, LLC of Boulder, Colo. Interface chassis 114 interfaces IF modulator/receiver chassis 112 with pulse control circuits 116 and Radar Processor (RP) 118.
Pulse control circuits 116 may comprise pulse control circuitry known in the art for generating pulses of controllable width and timing. Pulse control circuits 116 generate output pulses which may be converted into a Doppler radar output signal through interface chassis 114, IF modulator/receiver chassis 112, RF coherent up/down converter 108, Traveling Wave Tube Amplifier (TWTA) 110, circulator 104 to antenna 102.
Reflected signals from clouds are received by Antenna 102 and pass back through circulator 104, receiver protection switch 105, LNA 106, RF coherent up/down converter 108, IF modulator/receiver chassis 112, and through interface chassis 114 to Radar Processor (RP) 118. Interface chassis 114 may convert received signals into digital form for analysis by Radar Processor (RP) 118.
Radar Processor (RP) 118 may comprise a Pentium™ based computer running IBM™ OS/2™ was chosen as the operating system for Radar Processor (RP) 118 as it may more readily interface with various instruments and devices of the radar system. In alternative embodiments of the present invention, other operating systems (e.g., Windows™ or the like) may be used in place of the OS/2™ operating system without departing from the spirit and scope of the present invention. The various instruments and devices 110, 108, 112, 114, 116, 105, 120, and 140 may be provided with an IEEE 488 interface (not shown), sometimes referred to as a general purpose interface bus (GPIB), or in a proprietary variant as the Hewlett-Packard™ interface bus (HPIB). Radar Processor (RP) 118 may be provided with an IEEE 488 interface to control the hardware devices, and monitor the radar's internal environment (temperatures, voltages, and switch faults) and external environment (temperature, relative humidity, and external electrical power), and other interfaces to collect radar data.
Radar Processor (RP) 118 comprises control processes to operate radio frequency (RF) hardware, collect analog/digital samples (A/D) of the IEEE 488 devices for health monitoring and remedial action, and transfer files to and retrieve files from Data Management Processor (DMP) 126.
System monitor and control block 120 may monitor temperature and humidity within the cargo container housing the equipment of FIG. 1, as well as power supply conditions. Through an IEEE 488 interface, system monitor and control block 120 may output data to Radar Processor (RP) 118.
Data Management Processor (DMP) 126 may also comprise a Pentium™ based computer running the Solaris™ operating system of Sun Microsystems, Inc. of Palo Alto, Calif. The Solaris™ operating system is a multi-user environment UNIX operating system. In alternative embodiments of the present invention, other operating systems (e.g., UNIX, LINUX, or the like) may be used in place of the Solaris™ operating system without departing from the spirit and scope of the present invention.
Data Management Processor (DMP) 126 handles raw data files from Radar Processor (RP) 118, calibrates the radar data, generates an RP health message, performs local data file backups, generates color-graphic displays, and places data files where a site data system may retrieve them.
Local access to either of Radar Processor (RP) 118 and Data Management Processor (DMP) 126 may be achieved through monitor 122 and keyboard 124 which may be coupled to either of Radar Processor (RP) 118 or Data Management Processor (DMP) 126 via switch 123. Alternately, separate monitors and keyboards may be provided for each of Radar Processor (RP) 118 and Data Management Processor (DMP) 126.
Radar Processor
Radar Processor (RP) 118 comprises the radar processor (RP), responsible for operating, collecting data from, and monitoring the health of, the various instruments and radar apparatus illustrated in FIG. 1.
FIG. 2 is a block diagram illustrating the communication paths between different RP processes within Radar Processor (RP) 118. After Radar Processor (RP) 118 is initialized, the OS/2™ operating system first sets up a file which allows Radar Processor (RP) 118 to log into and transfer files to and from Data Management Processor (DMP) 126. Then, all background processes needed to make Radar Processor (RP) 118 autonomous are started.
First, master error logger process 212 is started. Master error logger process 212 logs messages from all other processes which connect to it. Watchdog timer process 206, a multithreaded process, is used to insure that other processes do not lock up Radar Processor (RP) 118 and interfere with radar operations. IEEE 488 driver 216, a multithreaded processes, controls each device connected to the IEEE 488 bus used by Radar Processor (RP) 118. For example, IEEE 488 driver 216 receives requests from the controller process 202 to set bit(s) on digital input/output (DIO) devices or read A/D channels.
As each request to report A/D channel values is a different thread, each request may be reported asynchronously. Uninterruptable power supply (UPS) 140 protects Radar Processor (RP) 118 and Data Management Processor (DMP) 126 from power fluctuations. UPS driver 210, a multithreaded process, receives instructions from monitor process 222 and reports back requested UPS data.
Two multithreaded processes, monitor logger 224 and power logger 226 are started to record the monitor process data. Controller logger 204, a multithreaded process, records functioning of controller process 202.
Monitor process 222 is started next. Monitor process 222 is multithreaded and requests of IEEE 488 driver 216 and UPS driver 210 that they asynchronously report back information as requested at a specified interval. The data are formatted for output to monitor logger 224 or power logger process 226.
Controller process 202 is started next. Controller process 202 is multithreaded and requests IEEE 488 driver 216 to put devices into their startup state. Next, Traveling Wave Tube Amplifier (TWTA) 110 is brought from its "STANDBY" to its "ON" state.
Time synchronizer process 218 is then started. Time synchronizer process 218 queries the clock of Data Management Processor (DMP) 126 and synchronizes the clock of Radar Processor (RP) 118. Data Management Processor (DMP) 126 has a similar process which queries a time host used as a reference clock. Time synchronizer process 218 maintains the clock of Radar Processor (RP) 118 within one second of the clock of Data Management Processor (DMP) 126.
Finally, a master command, master.cmd, is called to pass the command stream control from the startup folder of Radar Processor (RP) 118 to a user command process. Pseudo code for master command master.cmd may be written as follows:
______________________________________Master.cmdRepeatDelete old processing semaphore filesBegin control sequence to collect and transferradar dataMove files retrieved from data managementprocessor to proper directoriesUntil popstop file exists______________________________________
As illustrated by the pseudo-code for master.cmd, master command master.cmd runs in an infinite loop. First, old files are deleted using command deflags.cmd. Old files are deleted in case Radar Processor (RP) 118 was not shut down properly. Master command master.cmd then calls control command control.cmd to acquire and transfer the next cycle of cloud radar data.
Next, master command master.cmd moves any new command, batch, or radar parameter files retrieved from Radar Processor (RP) 118 to their proper directories using move command movecmds.cmd. Finally, master command master.cmd loops back to the top and repeats these steps. The infinite cycle of master command master.cmd continues until the "popstop" file is found or Radar Processor (RP) 118 is told to shutdown via shutdown command 220.
Pseudo code for control command control.cmd may be written as follows:
______________________________________Control.cmdSet up paths for sequencing and moving dataCollect radar dataSequence and move collected dataTransfer collected data to Data Management ProcessorSet paths for high water programExecute high water program______________________________________
Control command, control.cmd, is the top level command which acquires and moves cloud radar data. First, the cloud radar data and log paths are set (setmover.cmd) for the mover process. Next, the cloud radar data are acquired (do -- pop.cmd).
FIG. 3 is a block diagram illustrating the sequence of steps in the file transfer. In step 310, controller log data, error log data, monitor log data, radar log data, radar header data and radar data are acquired by Radar Processor (RP) 118. In step 320, Radar Processor (RP) 118 sequences the data and moves the data to a holding area in the hard drive of Radar Processor (RP) 118. In step 330, the data are transferred from Radar Processor (RP) 118 to Data Management Processor (DMP) 126 in a File Transfer Protocol (FTP) command. In step 340, the data from step 310 are removed from Radar Processor (RP) 118.
Acquired cloud radar data and logger files are sequenced and moved by the mover process from their acquisition directories to the transfer directory (holding area). Files in the transfer directory are then transferred to Data Management Processor (DMP) 126 using command do -- netio.cmd. New command, batch or radar parameter files are transferred from Data Management Processor (DMP) 126 to Radar Processor (RP) 118 using a reverse path.
Finally, the high watermark program (highwater) 214 is run. If data transfer from Radar Processor (RP) 118 to Data Management Processor (DMP) 126 fails for any reason, there is sufficient storage space within Radar Processor (RP) 118 to hold data and log files. The number of files which may be stored within Radar Processor (RP) 118 depends upon the size and type of the files. For example, fewer spectra data files may be held than moment data files because of their relative sizes. High watermark program 214 allows the file system to grow a certain percentage of total disk capacity. When this capacity is surpassed, the oldest data and log files in the transfer directory are deleted until the file system is within bounds, or there are no further candidate files to delete.
Pseudo code for cloud data radar acquisition command do -- pop.cmd may be written as follows:
______________________________________do.sub.-- pop.cmdPut the TWTA into "operate" modeWait until TWTA is in "operate" modeRun the radar processor to collect data______________________________________
Radar acquisition command do -- pop.cmd is the command file which controls the cloud radar sub-system and collects cloud radar data. Command do -- pop.cmd first calls setmode process 200 to request that controller process 202 put Traveling Wave Tube Amplifier (TWTA) 110 into is "operate" mode. Next, a TWTA monitoring program popsched 215 is called which opens a path to IEEE 488 driver 216 and requests the operating status of Traveling Wave Tube Amplifier (TWTA) 110.
Popsched 215 program will exit only when Traveling Wave Tube Amplifier (TWTA) 110 indicates that it has placed itself into "operate" mode. Finally, the profiler online program (POP) is run to collect cloud radar data. The profiler online program (POP) is copyrighted software of Radian International, LLC, of Austin, Tex.
The mover process uses a file (c:\mover.dat) of directory path names and file name extensions set up by the setmover.cmd to move and sequence the log and data files as discussed above in connection with control command control.cmd. For each directory path name, the mover process looks for files of the extension(s) requested. For each unique file type/extension pair, a four digit sequence number is appended to the file name. The sequence is reset to zero each day at 0000 UTC.
This sequencing feature may be required as the POP generates only daily file names. The four digit sequence number allows for 10,000 intervals during each 24 hour period, for a minimum interval size of two minutes. The files are then moved to a transfer directory and are ready to be transferred to Data Management Processor (DMP) 126.
Pseudo code for file transfer command do -- netio.cmd may be written as follows:
______________________________________do.sub.-- netio.cmdLog onto DMP and create the os2.sub.-- lock semaphore fileWhile there are files to be transferredTransfer data files into DMPIf the transfer was successfulRemove the files from the transferdirectoryend ifend WhileGet command files from DMPClean up command files on DMPRemove the os2.sub.-- lock semaphore file on DMP______________________________________
Do -- netio.cmd is the command file which transfers files to and from Data Management Processor (DMP) 126. First, the command logs into Data Management Processor (DMP) 126 as user mwcr (microwave cloud radar) 410 and executes a script which creates a lock file (os2 -- lock) in the home directory of user mwcr 410. The lock file tells the processing script (operating as user pds 430) in Data Management Processor (DMP) 126 not to execute because Radar Processor (RP) 118 is transferring files. Radar Processor (RP) 118 transfers files from the transfer directory in batches of ten, using File Transport Protocol (FTP).
After files have been successfully FTP'ed to the Data Management Processor (DMP) 126, they are removed from the transfer directory of Radar Processor (RP) 118. After all of the files are transferred from Radar Processor (RP) 118 to Data Management Processor (DMP) 126, Radar Processor (RP) 118 tries to retrieve new command, batch, or radar parameter files from Data Management Processor (DMP) 126. The, Radar Processor (RP) 118 logs into Data Management Processor (DMP) 126 and removes the command, batch, or radar parameter files that it just transferred. Finally, Radar Processor (RP) 118 logs into Data Management Processor (DMP) 126 as user mwcr 10 and removes the lock file.
Several ancillary programs are used to automate processes within Radar Processor (RP) 118. A watchdog killer program 208 is used to tell the watch dog timer 206 to exit after stopping the timer so that it cannot reset Radar Processor (RP) 118. Shutdown command 220 is used to kill well known OS/2™ processes and performs an OS/2™ shutdown system call (DosShutdown). The shutdown system call flushes the system buffers and the file system goes quiescent. In other words, the file system is safe from corruption when power is removed.
After a shutdown system call, it is safe to turn off power or press CTRL-ALT-DEL to reboot. In order to perform an unattended system reboot, shutdown command 220 accepts the command line argument "-R" for reboot. The "-R" argument causes shutdown command 220 to do all of the above as well as send a message to the watchdog timer to tell it to allow the timer to expire, thus causing a system reset.
An execute with time out program xwto, was developed as a generalized executor process which wraps any command script or program in a timeout structure. In other words, xwto will run a command script or program, at the same time keep track of the time the script or program has been running, kill the process if its allotted run time has expired before completion, and create a flag file so that other command scripts or programs know that the command timed out instead of running to completion. Command xwto is used to wrap all network command scripts so that they cannot, even in the case of a network failure while active, hang the POP radar data collection cycle.
In addition to collecting data from the radar system, Radar Processor (RP) 118 may also perform calibration functions on various equipment within the autonomous cloud radar system. FIG. 7 is a block diagram illustrating the steps performed by Radar Processor (RP) 118 in calibrating the radar system and generating radar calibration files. When prompted to perform a calibration, either at a predetermined time interval, or by command, Radar Processor (RP) 118 retrieves par file 702 containing calibration parameters.
Calibration parameters within par file 702 contain instructions as to which settings each piece of equipment within the autonomous cloud radar data system should have during different calibration tasks. In addition, par file 702 may contain data representing acceptable calibration ranges for different equipment. If one or more pieces of equipment generates calibration data which fall outside of a predetermined calibration range, the system may be shutdown and maintenance personnel notified via e-mail.
Shutdowns may be generated from either Data Management Processor (DMP) 126 or from Radar Processor (RP) 118. Radar Processor 118 may transmit a file shutdown.now to Data Management Processor (DMP) 126 indicating that a shutdown is to occur. From an external network, a shutdown.now file may be FTP'ed to Data Management Processor (DMP) 126, then may in turn transfer such a file to Radar Processor (RP) 118.
Radar Processor (RP) 118 may call AutoPar program 704 which may in turn switch calibration noise diode 132 into the radar circuit using T/R protection switch 105. A radar pulse or ping may be transmitted at a given frequency and time duration, and the resulting feedback signal measured. Separate calibration routines may be performed for different portions of the radar apparatus. MasterSkyCal routine 710 may generate calibration data representing "clear sky" background noise (as generated by calibration noise diode 132). Master RfCal routine 706 may be used to generate calibration data for RF components such as RF Coherent Up/Down Converter 108 and Traveling Wave Tube Amplifier (TWTA) 110.
MasterIfCal routine 712 may be used to generate calibration data for intermediate frequency components (e.g., IF Modulator/Receiver Chassis 112). All three calibration routines 710, 706, 712 generate calibration moment files Skycal.mom 714, Rfcal.mom 708, Ifcal.mom 716, respectively. Calibration moment files may then be transferred to Data Management Processor (DMP) 126 using the file transfer techniques discussed above.
Data Management Processor
Data Management Processor (DMP) 126 gathers data transferred from Radar Processor (RP) 118, processes such data, and transfers the data over a Local Area Network (LAN) 127 to a site data system. From the site data system, data may be made available to researchers throughout the world, either over the Internet, or a private or dedicated data network.
Data Management Processor (DMP) 126 performs a number of different functions by operating in a multi-user mode. FIG. 4 is a block diagram illustrating the relationship between multiple users on Data Management Processor (DMP) 126 and locations of various data and program files. Note that in the context of the present invention, the term "user" does not necessarily imply a physical human being, but rather may represent another computer system, network, program or suite of programs autonomously operating as a separate user in a multi-user mode of the computer system.
As discussed above, Radar Processor (RP) 118 may log onto Data Management Processor (DMP) 126 as user mwcr 410. Radar Processor (RP) 118, as user mcwr 410, may retrieve commands from directory 412 in Data Management Processor (DMP) 126 and upload data in the form of calibration data in directory 416, cloud data in directory 418, and system health information in directory 420 in directory tree 414 of user mwcr 410.
When Data Management Processor (DMP) 126 boots, a script file is executed (S98DeleteLockfiles) to remove any lock files which may not have been removed if the system was not properly shutdown. This script file is located in the /etc/rc2.d directory and is executed whenever the Solaris™ operating system goes into multi-user mode. The lock files removed are the ProcessLock and MSD -- Lock, in the home directory of user pds 430, and the os2 -- lock in the home directory of user mwcr 410.
Within Data Management Processor (DMP) 126, the UNIX cron process is used to schedule when user processes are executed. The Korn shell script name and its associated log file may be illustrated as follows:
______________________________________Process.script Process.YYYYJJJ.logHealth.script Health.YYYYJJJHH.LOGHighwater.script Highwater.YYYYJJJ.logArchive.script Archive.YYYYJJJ.logMoveLogFiles.script MoveLogfiles.YYYYJJJ.logCleanupFiles.script CleanupFiles.YYYYJJJ.logShutDown.script msd.YYYYJJJ.logTimeSynch.script______________________________________
Where YYYY is the four digit year, JJJ is the three digit Julian day of the year, and HH is the two digit hour. All script log file names are in the form NAME.YYYJJJ.log, except for the health message file, which has the form Health.YYYJJJHH.log, where NAME is the name of the script. Each log file is a daily log file except for the Health log file, which is hourly.
The user scripts process the data that Radar Processor (RP) 118 transfers to Data Management Processor (DMP) 126. Root scripts may have to be executed by the super user to shutdown the system or to set the system clock.
Pseudo code for the process Korn shell script may be written as follows:
______________________________________Process.scriptIf the Radar Processor is not transferring filesSet the Process.sub.-- LockIf new calibration data files exist thenExtract the calibration data from thecalibration moment filesend ifConvert the binary moment and spectra files tonetwork Common Data Format (netCDF)Convert the Monitor log files to netCDFConvert the Forward power log files to netCDFCalibrate the radar reflectivityMove required files to the Site Data System(SDS) outgoing directoryMove files from the SDS incoming directoryMove files to the circular directory treeRemove the Process.sub.-- Lockend if______________________________________
Process.script is the main processing script and is executed on a schedule which is consistent with the schedule of Radar Processor (RP) 118 sending data to Data Management Processor (DMP) 126. For example, if Radar Processor (RP) 118 is sending data to Data Management Processor (DMP) 126 every thirty minutes on the halfhour, Process.script may be run each half hour at five and thirty-five minutes after the hour. Such a schedule insures that all files are transferred from Radar Processor (RP) 118 before processing of data occurs.
Process.script first writes an entry to the process log file in directory 434 indicating that the script has begun. It then determines whether another Process.script is running by checking for the existence of the ProcessLock file in the home directory of user pds 430. If the ProcessLock file exists, then the script posts a message to the process log file in directory 434 and exits.
If the ProcessLock file does not exist, the script then determines if the Radar Processor (RP) 118 is transferring files to Data Management Processor (DMP) 126 (MwcrUser.script) by checking the Radar Processing (RP) 118 lock file (os2 -- lock in the home directory of user mwcr 410). If the os2 -- lock file is found, the script tries to determine if the Radar Processor (RP) 118 user mwcr 410 is logged in (UserLoggedIn.script). The UserLoggedIn.script checks the process status (ps) and looks for user mwcr 410. If user mwcr 410 is found, MwcrUser.script exits with a -1 status, which causes Process.script to exit without processing any files.
If user mwcr 410 is not found, then the script sleeps for ten seconds and tries again. MwcrUser.script may loop for a maximum of six times (i.e., 60 seconds). If, after 60 seconds, user mwcr 410 is determined not to be logged in, it is assumed that Radar Processor (RP) 118 did not clean up the os2 -- lock file and the MwcrUser.script will remove the os2 -- lock file and return the status of 0 to Process.script, which will continue processing.
Process.script then creates a ProcessLock file in the home directory of user pds 430 such that only one Process.script executes at a time. Data files in directories 416, 418, and 420 that Radar Processor (RP) 118 has placed in directory tree 414 of user mwcr 410 are moved to corresponding data directories 440, 442, 444 in directory tree 436 of user pds 430 by MwcrMover.script.
FIG. 5 is a block diagram illustrating the relationship between programs and files in Data Management Processor (DMP) 126 calibration extraction sequence. The CalMomExtract.script is executed to determine if there are any calibration moment files 502, 504, and 506, in calibration directory 440. If calibration moment files are present, then calibration data are extracted. Files 510, 512, and 514 in netCDF format are created for the Sky, RF, and IF POP calibration moment data 502, 504, and 506, respectively, using PopToNetCDF routine 508.
To generate a calibration curve, AutoCal program 516 is executed using Sky, RF, and IF netCDF files, 510, 512, and 514, respectively. Calibration curves 518 generated by AutoCal program 516 are written to CalibrationTable.nc file 520 in calibrate files 440 for use in calibrating cloud radar data.
FIG. 6 is a block diagram illustrating the relationship between programs and files in the calibration routine of Data Management Processor (DMP) 126. Cloud radar data files 602 are converted from binary POP format to netCDF format files 606 by the program PopToNetCDF 604 called by PopConvert.script and stored in directory 442.
Next, the forward power log files 622 are converted to netCDF by the program PowToNetCDF 624 called by ForwardPowerConvert.script. Then, cloud radar data netCDF files 606 are calibrated using the calibration data in the CalibrationTable.nc file 520 by the program Calibrate 608 called by CalibratePower.script to produce calibrated data 610 and 614. Calibrated data 610 appends to the raw moments file kept on Data Management Processor (DMP) 126. Calibrated data 614 is only the calibrated data and is placed in the outgoing directory 464 of user sds 460.
The next three Korn shell scripts move files which have been processed. First, data files wanted by the Site Data System are moved to the outgoing directory 464 of user sds 460 by MoveToSds.script. Then, any new command, batch, or radar parameter files in the incoming directory 462 of user sds 460 are moved to the commands directory 412 of user mwcr 410 using MoveFromSds.script.
Circular buffer directory 438 stores data for later retrieval by user sds 460 which may output such data, for example, over an internet, intranet, or other type of network. Files in directories 440, 442, and 444 of the data directory tree 436 to be stored in circular directory tree 438 of user pds 430 are moved to directories 448, 450, and 452, respectively, and files that are not needed are deleted by MoveToCircular.script. Finally, the Process Lock file is removed and an entry is written to the Process log file in directory 434 indicating that the script has finished.
Pseudo code for the health message Korn shell script may be written as follows:
______________________________________Health.scriptLog the network connection to the Radar ProcessorLog the latest moment data file name, size, andcreation timeRun the MonStats program on the monitor filesRun the MonStats program on the forward power files______________________________________
Health.script generates the CloudRadar health message and writes the health log file in health directory 452. The Health.script is executed each hour. The script first attempts a network "ping" of Radar Processor (RP) 118 and logs the results to the health message log file in directory 452. Next, Health.script logs the latest radar moment netCDF file including the file creation time and size to the health message log file in directory 452.
The MonStats program is then run on the monitor netCDF file(s) of the previous hour and the output logged to the health message log file in directory 452. Finally, health.script runs the MonStats program on the forward power netCDF file(s) of the previous hour and logs the output to the health message log file in directory 452.
HighWater.script executes the HighWater program and writes to the HighWater logfiles in directory 434. The directory trees monitored are the circular directory 438 of user pds 430 and the outgoing directory 464 of user sds 460. HighWater.script is executed each hour.
The number of files (and therefore how far back in time) which may be held depends upon the size of the files. For example, fewer spectra data files may be held than moment data files because of their relative sizes. The HighWater program allows the file system to grow to a certain percentage of the total disk capacity. When this capacity is surpassed, the oldest data and log files are deleted until the size of the file system is within bounds or there are no further candidate files to delete.
Archive.script executes the archive program and writes to the archive log file in directory 434. Archive.script executes once a day to perform a tar (tape archive) of the data and log files in directories 448, 450, 452, and 454 of the previous day. The output of tar is written to tars directory 456 and compressed. Archive determines if tar file(s)in tars directory 456 can be written onto tape 128 by checking the Archive history log file in directory 433 to calculate how full the tape is.
If Archive determines that there is enough room, then the tar file is written to a 4 mm DAT (Digital Audio Tape) drive 128. If there is not enough room on the DAT, an e-mail message may be sent to the operator of the Site Data System telling him/her to change the tape in tape drive 128. Each tape used by Archive.script is labeled with the tape name when the tape is first loaded.
Archive writes in its history file log in directory 433 the tape name, the file name, the data archived, and the file size. The file name may be in a format site.YYYYJJJ.TTTTTT.tar.Z, where site is a three character site name, YYYY is the four digit year, JJJ is the Julian day of the year, TTTTTT is a six digit tape sequence number, tar is an extension to indicate a tar file, and Z to indicate this is a UNIX compressed file.
Archive may also restore data from tape. A user indicates the date of the tar file to restore, and Archive prompts the user to place the proper tape into the tape drive by using information in the Archive history log in directory 433. Archive checks that the proper tape has been inserted, advances the proper number of files, and extracts the data file.
The MoveLogFiles.script is executed once per day to move all log files of the previous day from the data logfiles directory 434 into the circular buffer logfiles directory 454 of user pds 430. The MoveLogFiles.script writes to the MoveLogFiles log file in directory 434 to record its actions.
The CleanupFiles.script is executed once per day to remove temporary netCDF files used for plotting data from the data netCDF directory 446 of user pds 430, if the user that created such netCDF files is not presently logged into Data Management Processor (DMP) 126. Such superfluous netCDF files may be created if a user logs off Data Management Processor (DMP) 126 before exiting Condor, the Graphical User Interface (GUI) front end program which generates temporary netCDF plot files and creates color graphic displays. CleanupFiles writes to the CleanupFiles log file in directory 434 to record its actions.
The ShutDown.script is executed each minute (the time resolution of the UNIX cron process). It will cleanly shut down the operating system of Data Management Processor (DMP) 126 when a file named shutdown.now is found. ShutDown.script writes messages to the mds (monitor shutdown) log file in directory 434. ShutDown.script is run as the root user as only the root user can shutdown a UNIX operating system. When started, ShutDown.script checks to see if another ShutDown.script is running by checking for the MSD -- Lock file in the home directory of user pds 430.
If the lock file exists, then the script logs that fact and exits. If not, then the script goes into an infinite loop checking for the file shutdown.now in the home directory of user mwcr 410 or the incoming directory 462 of user sds 460. The script cycles between the two directories with a five-second delay before the next one is checked.
If the shutdown.now file is found in the mwcr user 410 home directory, Radar Processor (RP) 118 already knows to shut itself down, and Data Management Processor (DMP) 126 can cleanly shut itself down, ready for power to be cycled. If the shutdown.now file is found in the incoming directory 462 of sds user 460 directory, then Data Management Processor (DMP) 126 is being told to shutdown from outside the cloud radar system. Data Management Processor (DMP) 126 will first create a shutdown.now file in the root directory of Radar Processor (RP) 118 and then cleanly shut itself down, ready for power to be cycled.
TimeSynch.script executes the timesynch program to synchronize the internal system clock of Data Management Processor (DMP) 126 with the time of a time host with a resolution of one second. This script is run as the root user so that the system clock can be set. Radar Processor (RP) 118 also runs the timesynch program to synchronize its clock to Data Management Processor (DMP) 126.
Data Management Processor (DMP) 126 may be used as a color-graphics engine to display cloud radar data. Because the Condor program's Graphical User Interface (GUI) is written using the Motif look-and-feel and the color graphics using the X-Window system (e.g., Direct-X or the like), an X-capable system may be used for color-graphics display.
The Condor program has two functions; first, to gather the data that the user wants to display, and second, to create color-graphic displays of the data. To gather data, a user enters the date and time of the beginning and ending period of interest and whether moment or spectral data are desired. Condor performs a system call to makeBigMom or makeBigSpec to gather moment or spectral data, respectively. Either makeBigMom or makeBigSpec can be executed at the system prompt, but each has many command line arguments that Condor hides from the user.
If the data exist on Data Management Processor (DMP) 126, a netCDF file of the requested data are generated. Otherwise, an error message is displayed to the user. The user has the option of saving any netCDF file created by Condor which would be otherwise removed when the Condor program exits normally.
Gathered data may be displayed from within Condor, which performs a system call to the ncbrowser program, or by executing the ncbrowser program from the system prompt. Ncbrowser has its own GUI that allows a user to select a file to be used, the plot type, beginning and ending time, maximum and minimum heights, which variable(s) to plot, the variable(s) minimum and maximum, and, if appropriate, which of the unique radar parameter sets to use. If ncbrowser is called by Condor, the latest netCDF file created is used.
When all the information is entered, the color graphic is generated and displayed on the screen. Ncbrowser also has the ability to generate color PostScript or GIF output which may be transferred to the user's computer. FIG. 8 represents one such image for cloud radar data generated at the Department of Energy's Southern Great Plains (SGP) site for Feb. 17, 1998, representing reflectivity for a predetermined sequence of radar pulses. Examples of such data may be retrieved from the National Oceanic and Atmospheric Administration web site at http://www4.etl.noaa.gov/cloudrdr.html.
Note that although the image appears cloud-like, the image actually represents reflectivity data for different altitudes within the atmosphere at different times of day. Note also that every half-hour a blank band appears when data are transferred from Radar Processor (RP) 118 to Data Management Processor (DMP) 126. Other bands may appear when data are not available or if Radar Processor (RP) 118 has not completed its tasks from a previous scan. In general, dividing up radar processing tasks and data management processing tasks between the two computers allows for continuous data retrieval at increments of as little as 10 seconds per scan.
While the preferred embodiment and various alternative embodiments of the invention have been disclosed and described in detail herein, it may be apparent to those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope thereof. | A cloud radar apparatus is mounted on a portable containerized unit, a number of which may be located at various positions throughout the planet. Cloud radar data from each unit are periodically measured and stored and made available to researchers, upon request, through the Internet or other network. The system comprises two computers operating on different operating systems. A first computer uses a first operating system which allows it to readily interface with various radar equipment using an IEEE 488 interface or the like, to monitor the health of the equipment and operate the equipment. A second computer system uses a second operating system in a multi-user mode which allows it to readily access and manipulate data files and transfer data over the network. Communication between the two computers is achieved by allowing the first computer to log into the second computer as one of the multiple users. The first computer may upload data to the second computer using a FTP protocol or the like. A second user in the second computer may generate cloud radar images and apply calibration data to received data to produce calibrated data. A third user may be logged onto the second computer to handle data transfers to and from the network. By using two computers with operating systems selected for optimum performance with their respective tasks, the system of the present invention allows for completely autonomous operation of a remote radar site with automated collection and distribution of cloud radar data. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This non-provisional application claims the benefit of provisional application No. 61/807,191, filed Apr. 1, 2013, which application is incorporated herein in its entirety by this reference.
TECHNICAL FIELD
[0002] One embodiment of the present invention is a water kiosk that solves the problem of water being sold in non-compostable bottles. The kiosk enables the provision to consumers of bottled water or beverage in an easily biodegradable—“compostable”—beverage container for use in the sale of bottled water and other beverages. The beverage kiosk fills the container onsite at the time of purchase. The kiosk filters municipal water to a high level of purity, provides additives if desired by the consumer, fills a compostable beverage container, seals the cap, and delivers the sealed bottled water to the consumer.
BACKGROUND
[0003] Water and other beverages are sold to consumer either in bottles or other containers that are not “compostable” or at dispensers that fill a container brought by the purchaser. Such containers create many environmental problems, including adding mass to landfills, ending up as litter in the environment that does not degrade under natural conditions, and creation of significant carbon emissions through the transport of pre-filled bottles from bottling sites to points of sale. Most such containers are composed of aluminum or polyethylene plastic (PET).
[0004] To date, no company has been able to develop and put into commercial production a beverage container that degrades easily in the natural environment—meeting various state, national, and international standards for “compostability.” The reason for this failure is that a beverage container that degrades easily must be sold immediately, because degradation begins immediately upon filling. Thus, beverages cannot be bottled, shipped, and stored at points of sale without degrading to the point where they are unacceptable to consumers.
SUMMARY OF THE INVENTION
[0005] The solution, the way to provide a “compostable” container, is to fill the bottle only when the consumer buys the product. Then, the consumer has sufficient time to consume the beverage before significant degradation occurs. Providing such a solution requires a container designed for efficient delivery to points of sale, efficient storage at the point of sale, and filling processes that guarantee sterility and quality via a sealed cap.
[0006] One embodiment of the invention is directed to an eco-friendly beverage dispensing kiosk that takes in water from a standard local water supply facility and that dispenses bottled beverage to consumers, comprising at least one filter that filters water from the standard local water supply facility to remove impurities and to obtain filtered water, and a housing that contains empty beverage containers, each of the containers comprising a compostable material. The kiosk further includes a mechanism that fills at least one of the empty beverage containers with a beverage that contains the filtered water, seals the at least one container with a cap, and delivers the filled at least one container to a beverage recipient.
[0007] Another embodiment is directed to an eco-friendly beverage dispensing method comprising receiving water from a standard local water supply facility; and filtering water from the standard local water supply facility to remove impurities and to obtain filtered water. The method further includes filling at least one empty beverage container with a beverage that contains the filtered water, the at least one empty beverage container comprising a compostable material; sealing the at least one container with a cap, and delivering the filled at least one container to a beverage recipient.
[0008] All patents, patent applications, articles, books, specifications, standards, other publications, documents and things referenced herein are hereby incorporated herein by this reference in their entirety for all purposes. To the extent of any inconsistency or conflict in the definition or use of a term between any of the incorporated publications, documents or things and the text of the present document, the definition or use of the term in the present document shall prevail.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a diagram of a water kiosk with stored bottles, a filling mechanism, a delivery mechanism, and filters to illustrate one embodiment of the invention.
[0010] FIG. 2 is a diagram showing details of bottle storage and the filling mechanism of FIG. 1 .
[0011] FIG. 3A is a cross-sectional view diagram showing a sealing plug and cap body, where the sealing plug is inserted partially into the cap body through a hole.
[0012] FIG. 3B is a perspective view of the sealing plug and cap body of FIG. 3A .
[0013] FIG. 3C is a cross-sectional view diagram showing a sealing plug and cap body, where the sealing plug is inserted completely into the cap body through the hole to form a permanently sealed combined cap assembly.
[0014] FIG. 3D is a perspective view of the permanently sealed combined cap assembly of FIG. 3C sealing plug and cap body.
[0015] FIG. 3E is a top view of the main cap body with the sealing plug removed where a hole at the center of the main cap body is for receiving the sealing plug that is to be inserted into the hole of the main cap body first partially and then completely after filling the bottle. FIG. 3 is useful for illustrating another embodiment of the invention.
[0016] FIG. 4A is a diagram showing the bottle and cap assembly in a filled and permanently sealed condition.
[0017] FIG. 4B is a diagram showing a bottle with the cap plug inserted partially and ready for filling.
[0018] FIG. 5 shows a network of kiosks connected by a communication network to a central computer that contains a database of information about the kiosks and the customers buying beverages from the kiosks.
[0019] For simplicity in description, identical components are labelled with the same numerals in this document.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0020] In one embodiment, the above described problems with producing compostable bottled water or beverage can be alleviated by having a kiosk that uses the municipal water supply, filters the water, provides additives in accordance with consumer preferences, fills compostable bottles stored in the kiosk, and delivers a sealed, filled bottle to the consumer. In its preferred embodiment, which is but one of many alternatives, the beverage container consists of an external shell, internal pouch, and cap. Its shape is that of a typical beverage bottle. The shell may be of an easily degradable material such as wood or bamboo pulp. To keep the beverage from leaking through the shell, the beverage is contained within a waterproof pouch inside the shell. The pouch may consist of poly-lactic acid (PLA) in such thickness and of such type that it meets regulatory requirements to be certified as “compostable.” The cap may be a typical cap with threads to screw onto the top of the container or an alternative. The cap may be made of wood, PLA, or another material. See figures below for illustration. To meet regulatory requirements, the entire container, or just the shell and pouch, may be certified as “compostable” by certification organization Vincotte (Brussels, Belgium) or a similar entity.
[0021] In another embodiment, the shell consists of a cylindrical tube with a narrower opening on top and a bottom that is hinged and not attached when the containers are shipped to the point of sale. The point of sale may be a beverage kiosk or other point of retail sale. The pouch may be attached at the top of the shell and to the hinged bottom so that the pouch does not collapse when the beverage is consumed. Because the hinged bottom is not attached at the time of shipping, the containers may be stacked efficiently, with several hundred containers able to be stacked and stored within a space within a kiosk housing that is smaller than the size of a typical vending machine (1×4×6 feet), and allowing for other equipment inside the housing.
[0022] In still another embodiment of the invention, the container is folded and shipped to the point of sale. As with stacking, having folded containers allows storage of several hundred containers within a kiosk housing space the size of a typical vending machine.
[0023] In yet another embodiment of the invention, a data collection interface is employed to interface with the meter data collection system. A number of software applications for cleaning, validating and estimating data are employed. A message bus transfers data or information derived from the data between the data collection system, the data collection interface and the software applications. By employing a number of different software applications to perform the functions of cleaning, validating and estimating data, where the software applications communicate with one another and with the data collection interface through the message bus, efficiency and flexibility of the cleaning, validating and estimating functions performed by the software applications are improved.
[0024] In any embodiment, when a consumer purchases the beverage, the container is filled and delivered to the consumer or beverage recipient. In this document, the terms “purchaser,” “consumer” and “beverage recipient” are used interchangeably. In one embodiment, the container is delivered to the point of sale with a cap and seal attached to the top. The container is filled through the bottom, and the bottom is then attached to the rest of the shell, completing the final container. In another embodiment, the container is filled through the top, after which the cap is added. Following consumption, the consumer may discard the container in a bin labeled for compost.
[0025] In one embodiment, the above described problems of producing compostable bottled water or beverage can be alleviated by having a kiosk that uses the municipal water supply, filters the water, provides additives in accordance with consumer preferences, fills compostable bottles stored in the kiosk, and delivers a sealed, filled bottle to the consumer. In its preferred embodiment, which is but one of many alternatives, the beverage container consists of an external shell, internal pouch, and cap. Its shape is that of a typical beverage bottle. The shell may be of an easily degradable material such as wood or bamboo pulp. To keep the beverage from leaking through the shell, the beverage is contained within a waterproof pouch inside the shell. The pouch may consist of poly-lactic acid (PLA) in such thickness and of such type that it meets regulatory requirements to be certified as “compostable.” The cap may be a typical cap with threads to screw onto the top of the container or an alternative. The cap may be made of wood, PLA, or another material. See figures below for illustration. To meet regulatory requirements, the entire container, or just the shell and pouch, may be certified as “compostable” by Vincotte (Brussels, Belgium) or a similar entity.
[0026] FIG. 1 is a block diagram illustrating one embodiment of the invention. As shown in FIG. 1 , the kiosk 1 contains the elements necessary to produce and deliver bottled water or other beverages to the purchaser. Water from a municipal water supply facility enters the kiosk via manifold 33 and is connected to filters 5 that remove impurities, including both inorganic chemicals and undesirable microbes. Bottles are stored in cartridge 3 prior to filling in stacks as shown in FIG. 2 . The bottles are retrieved by a robot arm and placed in a carousel to be filled by filler 4 in FIG. 1 . The water is delivered through tubes to filler 4 , and then injected into the bottle. The filled bottle is sealed and delivered to the consumer through the delivery mechanism 2 , as shown in FIG. 1 .
[0027] FIG. 2 illustrates the storage and handling of bottles in this embodiment. The bottles are stored in stacks 41 in a partially-completed state in the kiosk, with their bottoms only partially attached. During the filling and sealing process, the bottoms are attached. Filling collar 42 of filler 4 injects water through a hole in a pre-installed cap to fill the bottles. The use of a carousel allows one bottle to be filled while another is taken by the robot arm from storage and added to the carousel. Another bottle can then be filled immediately with a short rotation of the carousel without waiting for the robot arm to retrieve a bottle from the stack.
[0028] FIGS. 3A-3E illustrate the cap system in a second embodiment to deliver the sealed bottle of an embodiment. In this embodiment, the cap has two parts: sealing plug 21 and cap body 22 . Following manufacture of the sealing plug and cap body, the sealing plug is inserted partially into the cap body through hole 26 as illustrated in the cross-sectional view of FIG. 3A to form the partially sealed plug and cap body assembly 24 also shown in FIG. 3B in perspective. Four holes 27 are defined in the cap body as shown in FIGS. 3A and 3E . FIG. 3E is a top view of the main cap body with the sealing plug removed where a hole 26 at the center of the main cap body is for receiving the sealing plug that is to be inserted into the hole of the main cap body first partially and then completely after filling the bottle. This partially sealed plug and cap body assembly 24 is screwed onto the bottle at a centralized facility and the breakable paper or plastic seal 35 in FIG. 4B is attached via adhesive or as shrink-wrap commonly used in the industry. The partially sealed plug and cap body assembly 24 is delivered to the kiosk already screwed onto the bottle as shown in FIG. 4B . The beverage is injected through the four holes 27 in partially sealed plug and cap body assembly 24 . After filling, a solenoid (not shown) plunges the plug 21 completely into the cap body 22 to create the sealed plug and cap body assembly 25 shown in FIG. 3C . The assembly 25 is then a permanently sealed combined cap assembly having an appearance attractive to the consumer and similar to typical plastic bottle caps. The permanently sealed combined cap assembly 25 is shown in the perspective view in FIG. 3D , and in cross-section in FIG. 3C . In other words, the holes 27 through which water is injected are permanently sealed following the filling of the bottle. The Kiosk 1 also preferably includes a refrigeration unit in manifold 33 that chills the water before it is injected into the bottle. The filler 4 , the refrigeration unit, the solenoid unit that seals the holes 27 , and the robot arm that delivers the filled bottle to the recipient are collectively referred to herein as the “mechanism.” To consume the beverage, the consumer will first need to break the seal 35 by unscrewing the cap and removing it from bottle 34 . The bottle and cap assembly in a filled and permanently sealed condition is shown in FIG. 4A .
[0029] FIG. 1 illustrates a further embodiment, in which the kiosk has a QR reader or camera 8 to read a QR code displayed by the purchaser's smart phone 6 in another embodiment. The QR code communicates the purchaser's identity and other information such as payment preferences. The QR code may also be displayed on the tablet computer 10 or on the laptop computer 9 instead of smart phone 6 . A smart phone, a tablet computer and a laptop computer are referred to herein collectively as a handheld computer.
[0030] In a still further embodiment shown in FIG. 1 , the purchaser may select additives for the water to be added following filtration and prior to filling the bottle. The selected additives are combined with the water in filler 4 and injected into the bottle. Additives selected by the end consumer are communicated from the handheld computer such as smart phone 6 via wireless communications to receiver 7 . The handheld computer may also be tablet computer 10 or laptop computer 9 . A wireless receiver similar to receiver 7 may be used to establish two way communication between the kiosk and a centralized computer linked to or with a database providing information to the kiosk as illustrated in FIG. 5 .
[0031] In a yet further embodiment illustrated in FIG. 1 , the purchaser may communicate payment information such as identification and account number to the kiosk as well as authorization for payment for the filled container beverage by the purchaser's financial institution on behalf of the purchaser. Payment information for the end consumer or purchaser is communicated from the handheld computer such as smart phone 6 via wireless communications to receiver 7 . The handheld computer may also be tablet 10 or laptop computer 9 .
[0032] In another further embodiment illustrated in FIG. 1 , the kiosk has a computer processor 11 that can communicate with a payment processing computer (not shown) at a payment facility (not shown) via wireless link 7 to enable automatic deduction from a pre-paid account that was funded by the beverage recipient in advance of the purchase.
[0033] In a further embodiment illustrated in FIG. 1 , the kiosk 1 has computer processor 11 that contains or is linked to a database 12 of information about persons previously utilizing the kiosk. This database may be linked, to centralized database 13 illustrated in FIG. 5 . In the embodiment illustrated in FIG. 5 , the kiosk of FIG. 1 may be one of the kiosks 14 , 15 , 16 in and forms part of a network of kiosks 14 , 15 , and 16 that are connected via communications network 17 to a central database 13 connected to computer processor 28 and housed at centralized facility 31 . The central database 13 contains in one embodiment information about persons previously utilizing any one of the kiosks that is part of the network of kiosks. Alternatively, the central database 13 may also be stored in the computer processor 28 .
[0034] In yet another further embodiment illustrated in FIG. 1 , the kiosk produces bottled beverages without creating wastewater. Water is received through intake manifold 33 and passed through filters 5 before bottling. Only sufficient water is processed in order to fill a bottle. Any excess water is stored in filler 4 and utilized in filling a subsequent bottle. Filters 5 may include the use of ultraviolet light, or may include a reverse osmosis filter, or a charcoal filter, or any combination or subset of the three. In one embodiment, the charcoal filter requires no flushing, because it is replaced via maintenance activities before reaching full utilization.
[0035] In one more embodiment illustrated in FIG. 1 , tubing carries water from manifold 33 to filler 4 . The kiosk utilizes only tubing that allows no detectable leaching of impurities in the liquid as the liquid flows through the tubing. Such tubing may include some stainless steel tubing.
[0036] In yet another embodiment shown in FIG. 1 , filler 4 includes tubes connected to additive containers stored in filler 4 . The kiosk adds additives to the water via filler 4 during the filling process. The additives are selected by the recipient of the beverage. In one embodiment, the additive is one or more flavors. In other embodiments, the additive is carbonation, caffeine, or an additive that increases or decreases the pH of the beverage.
[0037] In an embodiment shown in FIG. 5 , kiosk 14 has a wireless communications component (not shown but similar to wireless link 7 of FIG. 1 ) to communicate via communications network 17 to retrieve the beverage recipient's preferred set of additives from database 13 housed at centralized facility 31 remote from the kiosk. This may be performed by means of the wireless communications component or receiver of kiosk 14 receiving wireless signals from a handheld computer of the recipient. The wireless signals carry information about the purchaser's preferred additives, and the mechanism adds the preferred additives to the water filtered from the standard local water supply facility before filling the at least one container.
[0038] FIG. 5 illustrates a further embodiment of the invention in which the kiosk is part of a network of kiosks and where a closed-loop maintenance system is used to maintain the kiosk. Such kiosks are connected to computer processor 28 at central facility 31 via communications network 17 . The centralized database 13 is connected to computer processor 28 . The database may contain information about the kiosks and number of beverage containers filled at each kiosk in the network. The database may contain information about all the service calls to each kiosk and information about the history of the filters and pumps in each kiosk in the network.
[0039] FIG. 1 illustrates one further embodiment, in which bottles are stored in cartridge 3 prior to filling. The use of cartridges allows for efficient maintenance, because bottles can be pre-loaded into the cartridges at a central maintenance facility. The loaded cartridges can then be quickly exchanged in the kiosk, allowing for addition of hundreds of empty bottles with a minimum of manual labor and in a short time period.
[0040] While the invention has been described above by reference to various embodiments, it will be understood that changes and modifications may be made without departing from the scope of the invention, which is to be defined only by the appended claims and their equivalents. | A beverage dispensing kiosk that contains empty beverage containers and fills them with water and other beverages. The beverage containers comply with applicable regulations and standards to be designated “compostable.” The kiosk uses municipal water as the base, purifies the water, and adds constituents to meet the taste of the ultimate consumer. The delivered beverage may be commonly known as bottled water or as a soft drink, such as a cola beverage. | 2 |
BACKGROUND
[0001] This relates generally to active management technology.
[0002] Active management technology, available from Intel Corporation, Santa Clara, Calif., allows network administrators to discover, heal, and protect their networked computing assets. See Intel® Active Management Technology Deployment and Reference Guide, Version 1.0, October 2006, available from Intel Corporation, Santa Clara, Calif. It uses transport layer security (TLS), Hypertext Transfer Protocol (HTTP) Digest Authentication, Kerberos Authentication, access-controlled storage, session keys, and a random number generator to deploy these capabilities in a secure way.
[0003] The active management technology is set up and configured in a relatively careful way. Conventional setup generally requires an information technology technician to input several pieces of information manually, including the HTTP digest password and the provisioning pass phrase (PPS)/provisioning identifier (PID) pair.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a system architecture in accordance with one embodiment of the present invention; and
[0005] FIG. 2 is a flow chart for the embodiment shown in FIG. 1 .
DETAILED DESCRIPTION
[0006] In accordance with one embodiment of the present invention, an active management technology device may be set up and configured by creating a live operating system (OS) compact disk. A live OS is a complete solution, on a disk, for using a computer without operating a hard drive. It may contain a customized, full fledged operating system, such as, for example, the Linux LiveDistro, such as Ubuntu which has the ability to boot itself from a compact disk. The compact disk may also include the Host Embedded Controller Interface (HECI) device driver for the operating system. In the example just described, the device driver might be the Linux HECI driver. In addition, the disk includes a set up and configuration client (SCC) application that communicates with an active management technology set up and configuration application (SCA) to retrieve the needed parameters and to provision the active management technology device locally through the HECI driver. Finally, the compact disk may include a script to automate the provisioning process after the live operating system boot up.
[0007] Referring to FIG. 1 , the active management technology device 10 communicates through a network connection 42 with a set up and configuration application server 12 . The active management device 10 includes a host operating system 14 and an active management technology management engine 16 . The engine 16 includes the server application 30 and the simple object access protocol (SOAP), HTTP and transport layer security (TLS) module 32 . Connected to the module 32 is the HECI driver 34 and TCP/IP module 36 . A LAN (local area network) driver 38 couples by a communication interface 40 to the local area network hardware 26 of the host operating system 14 .
[0008] The host operating system 14 includes a set up and configuration client 18 , its SOAP, HTTP, and TLS module 20 , and its own Transmission Control Protocol (TCP)/Internet Protocol (IP) module 22 , as well as its own LAN driver 24 . The host also includes an HECI driver 38 , coupled by an HECI interface to the HECI driver 34 of the management engine (ME) 16 .
[0009] The LAN hardware 26 is coupled by the network connection 42 to the server 12 . In order to provision and configure the set up and configuration application, the application is configured with the predefined parameters using the live operating system compact disk. Those predefined parameters include a certificate, a random number generator seed, and access control lists (ACLs) for the active management technology management security, as indicated in block 62 ( FIG. 2 ). The active management technology device is powered on and connected to the network, as indicated in block 64 . A technician then inserts the live operating system compact disk into a compact disk player. The operating system from the disk is automatically booted and gets an Internet Protocol address from a Dynamic Host Configuration Protocol (DHCP) server and an SCA server Internet Protocol address from a domain name system (DNS). Then, the set up and configuration client application is started by the script, as indicated in block 68 .
[0010] Next, as indicated in block 70 , the set up and configuration client application 44 communicates with the set up and configuration application 18 by a TLS connection and gets the predefined management security parameters. The set up and configuration client application 44 then sets the parameters into the active management technology hardware through the host embedded control interface driver 28 , as indicated in block 72 .
[0011] After successful provisioning, the active management technology device 10 is rebooted and the live operating system compact disk may be removed. Then, the active management technology device 10 can be connected by an appropriate third party active management technology management console remotely and securely.
[0012] In accordance with some embodiments of the present invention, the support and provisioning of the active management technology engine firmware may be offloaded to the host software. The operating system from the live operating system disk and the system central processing unit can use more secure TLS protocols instead of TLS-pre-shared key (PSK) protocols during the provisioning phase. They can also use the more secure Kerberos authentication instead of the weaker HTTP digest authentication during provisioning. Some embodiments may more easily add, modify, enhance, and extend features and functionalities on the set up and configuration client program than on the management engine firmware, making it easier to achieve zero touch active management technology set up and configuration.
[0013] An embodiment may be implemented by hardware, software, firmware, microcode, or any combination thereof. When implemented in software, firmware, or microcode, the elements of an embodiment are the program code or code segments to perform the necessary tasks. The code may be the actual code that carries out the operations, or code that emulates or simulates the operations. A code segment may represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a class, or any combination of instructions, data structures, or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc. The program or code segments may be stored in a processor readable medium or transmitted by a computer data signal embodied in a carrier wave, or a signal modulated by a carrier, over a transmission medium. The “processor readable or accessible medium” or “machine readable or accessible medium” may include any medium that can store, transmit, or transfer information. Examples of the processor/machine readable/accessible medium include an electronic circuit, a semiconductor memory device, a read only memory (ROM), a flash memory, an erasable ROM (EROM), a floppy diskette, a compact disk (CD-ROM), an optical disk, a hard disk, a fiber optic medium, a radio frequency (RF) link, etc. The computer data signal may include any signal that can propagate over a transmission medium such as electronic network channels, optical fibers, air electromagnetic, RF links, etc. The code segments may be downloaded via computer networks such as the Internet, Intranet, etc. The machine accessible medium may be embodied in an article of manufacture. The machine accessible medium may include data that, when accessed by a machine, cause the machine to perform the operations described in the following. The term “data” here refers to any type of information that is encoded for machine-readable purposes. Therefore, it may include program, code, data, file, etc.
[0014] References throughout this specification to “one embodiment” or “an embodiment” mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation encompassed within the present invention. Thus, appearances of the phrase “one embodiment” or “in an embodiment” are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be instituted in other suitable forms other than the particular embodiment illustrated and all such forms may be encompassed within the claims of the present application.
[0015] While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention. | An active management technology device may be provisioned using a live operating system stored on a disk, in one embodiment. After disk insertion, no further operator involvement may be needed in some cases. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates in general to a surgical accessory, and more particularly, to a two-piece retrievable catheter for replacement of a dislodged T-tube previously surgically implanted in the internal ducts or vessels of a patient as a conduit to stent and/or provide drainage after a surgical procedure, for example, the common bile duct following surgery to remove gallstones or the gallbladder itself.
The surgical implantation of a T-tube following surgery, in particular, open cholecystectomy, is well-known in the medical field as well as the patent literature. Typically, these T-tubes are made from a highly flexible material so that when their function is no longer needed, they may be removed by simply pulling them out of the patient. For example, Goldberg et al., U.S. Pat. No. 3,835,863, discloses a flexible T-tube which is surgically implanted in an internal duct or vessel of a patient in order to facilitate the removal of the T-tube when it is no longer needed. The T-tube includes a continuous slit extending longitudinally across the top of the cross tube. As the T-tube is pulled out from the patient for removal, the longitudinal slit causes the arms of the cross tube to telescope within each other to form a smaller cross-section which minimizes the amount of trauma and stress in the duct. T-tubes without a slit are known from Morales-George, U.S. Pat. No. 4,654,032 and Whelan, Jr., U.S. Pat. No. 4,142,528.
Hartenbach, U.S. Pat. No. 3,833,940 discloses a metal or plastic cannula which is surgically implanted in the bile duct of the patient. A radially extending nipple in communication with the interior of the cannula protects against the longitudinal displacement of the cannula and permits a drainage hose to be connected thereto. Optionally, one or both of the end sections of the cannula may be detachable from the nipple portion, thereby making the implantation of the cannula within a bile duct easier.
Swartz, U.S. Pat. No. 4,072,153, discloses a flexible T-tube for use as a fluid drainage tube following a hysterectomy. A large central drain port formed at the intersection of the cross tube and drain tube causes the arms of the cross tube to fold up on one another as the drain tube is pulled, thereby facilitating the withdrawal of the tube from the patient.
Jones, U.S. Pat. No. 4,248,224, discloses a double lumen flexible catheter having a generally Y or T shape formed at a distal end. A substantially stiff sleeve is slidably fitted over the cannula. As the sleeve is slid over the lower branch portions at the distal end of the catheter, it urges the branch members into alignment with the upper fluid conveying tube so the entire structure can be passed through a relatively small single surgical opening. Once properly positioned, the sleeve can be retracted so that the two branch members return to their Y or T configuration within the duct.
Grunwald, U.S. Pat. No. 4,309,994, discloses a flexible Y or T shaped cannula which is similar to that of Jones. The divergent ends of the cannula are straightened for insertion into the vena cavae of a patient by an elongated obturator slidably inserted therein. The obturator includes a straight body having two straight branches extending from one end thereof. As the obturator is slid into the cannula, the branches engage and straighten the branches of the cannula to facilitate the insertion of same into the vena cavae through a single surgical opening. Upon withdrawal of the obturator, the branches of the cannula will return to their normal Y or T configuration.
Patel, U.S. Pat. No. 4,748,984 discloses a catheter assembly for use in performing coronary angiography and angioplasty. The catheter consists of an elongate guiding portion having a tip portion pivotally connected thereto. A guide wire inserted into the guiding catheter and tip portion maintains these elements in alignment as the assembly is inserted into the patient's aorta. The guide wire is then removed and the guiding catheter maneuvered until the tip portion pivots to a position adjacent the tip of the guiding catheter. In addition, the tip portion of the catheter may be curved to form a loop.
In addition to the T-tube, it is also known that catheters having a straight configuration may be inserted into a patient over a guide wire. Once inserted, the guide wire is removed, and by pulling on a suture or series of sutures threaded therethrough, the tip of the catheter may be curled to form a loop or S-shape. When the catheter is no longer needed, the tension on the suture is relieved and the guide wire reinserted, thereby straightening the catheter for removal.
Despite these known medical devices and surgical procedures, replacement of a dislodged T-tube may be impossible or difficult, at best. Reinsertion of a soft surgical T-tube requires folding of the trailing limb and this doubled tubing may not pass through the undilated or tortuous T-tube tract. If the T-tube is dislodged early in the post-operative period, replacement may result in tract perforation and peritonitis. When retained common bile duct stones or obstructions from sticture or neoplasm are present, T-tube replacement is mandatory. If a T-tube cannot be replaced, biliary drainage catheters can be used, but these may leak, drain poorly or become malpositioned. Accordingly, there is an unsolved need for a T-tube catheter which can easily be placed percutaneously within a patient for replacement of a dislodged T-tube, particularly during the post-operative period.
SUMMARY OF THE INVENTION
A retrievable T-tube catheter has been developed in accordance with the present invention for easy insertion into the common bile duct. The T-tube catheter has a two piece design, but is introduced as a single unit over an introducer cannula and guide wire. The T-tube catheter is then formed upon removal of the guide wire and cannula in-situ within the common bile duct. A suture-locking device affords self-retaining characteristics and the T-tube catheter can be easily retrieved, repositioned or exchanged. The T-tube catheter can be modified within a long distal limb to stent the Ampulla of Vater after balloon sphincteroplasty. Alternatively, a second type of catheter with a self-retaining loop can be used as an internal biliary drainage catheter when treating distal common bile duct obstruction. This T-loop catheter is inserted through the T-tube tract and avoids placement of a transhepatic catheter.
In the present invention, an elongated main catheter and a separate and distinct auxiliary catheter are assembled in axial alignment over a cannula for insertion into the common bile duct or similar vessel or canal within the patient. Two sutures threaded through the main catheter are attached to the auxiliary catheter, one in the center of the auxiliary catheter and one at an end thereof. After the two piece catheter has been inserted to the desired location and the cannula removed, the sutures are manipulated to maneuver the auxiliary catheter until it lies perpendicularly to the elongated main catheter to thereby form a T-tube.
For removal of the catheter from the patient through the T-tube track, the sutures are once again manipulated to align the auxiliary catheter with the elongated main catheter. The cannula is then inserted through both the elongated main and auxiliary catheters and the entire assembly is removed together. Both the insertion and removal procedures are performed with the aid of an X-ray television to assure that the elongated main and auxiliary catheters are properly aligned. Not only may the present invention be used for the in-situ formation of T-tubes but, with the proper arrangement of sutures, T-loops may be formed in-situ as well.
In accordance with one embodiment of the present invention, there is disclosed a two piece retrievable catheter for insertion into the duct of a patient to provide a conduit from inside the duct to outside the body wall of the patient. The catheter is constructed of a first catheter portion a second catheter portion, and connecting means for connecting the first catheter portion to the second catheter portion in two different configurations upon manipulation of the connecting means while the second catheter portion is positioned within the duct, the second catheter portion providing fluid communication between the duct and the first catheter portion when arranged in at least one of the two different configurations.
In accordance with another embodiment of the present invention, there is disclosed a two piece retrievable catheter for insertion into the common bile duct of a patient to provide a conduit from inside the duct to outside the body wall of the patient. The catheter is constructed of a main catheter, an auxiliary catheter, and connecting means for connecting the main catheter to the auxiliary catheter upon manipulation of the connecting means. The manipulation of the connecting means arranges the auxiliary catheter between a first position in longitudinal alignment with the main catheter for insertion of the catheter into the common bile duct and a second position in angular relationship with the main catheter for fluid communication with the common bile duct.
BRIEF DESCRIPTION OF THE DRAWINGS
The above description, as well as further objects, features and advantages of the present invention will be more fully understood with reference to the following detailed description of a two-piece retrievable catheter, when taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view of a two-piece retrievable catheter constructed in accordance with one embodiment of the present invention;
FIG. 2 is a side elevational view of the distal portion of the two-piece retrievable catheter shown in arrangement for insertion into the patient such as the common bile duct;
FIG. 3 is a side elevational view of the distal portion of the two-piece retrievable catheter which has been manipulated in-situ after insertion into the patient to form a T-limb;
FIGS. 4A-4D are side elevational views showing alternative construction features for uniting the two-piece retrievable catheter to form the T-limb as shown in FIG. 3;
FIG. 5 is a side elevational view of the auxiliary catheter of the two-piece retrievable catheter in accordance with another embodiment of the present invention;
FIG. 6 is a side elevational view of the auxiliary catheter of the two-piece retrievable catheter forming a T-loop in accordance with another embodiment of the present invention;
FIG. 7 is a side elevational view of the proximal portion of the two-piece retrievable catheter in accordance with another embodiment of the present invention including a detachable suture storage device;
FIGS. 8(a)-(d) is a diagrammatic illustration showing replacement of a dislodged previously surgically inserted T-tube with the two-piece retrievable catheter of the present invention into the common bile duct of a patient;
FIG. 9 is a side elevational view of another embodiment of attaching the auxiliary catheter to a suture for manipulation to form the T-limb; and
FIG. 10 is a side elevational view of another embodiment of attaching the auxiliary catheter to a suture for manipulation to form the T-limb.
DETAILED DESCRIPTION
Referring now to the drawings, wherein like reference numerals represent like elements, there is shown in FIG. 1 a two-piece retrievable catheter constructed in accordance with the present invention and generally designated by reference numeral 100. The catheter 100 includes a single lumen flexible main catheter 102 and a flexible single lumen or T-limb auxiliary catheter 104 operatively connected by sutures 106, 108. The proximal portion of the main catheter 102 includes a conventional locking valve 110 and an enlargement 112 in the nature of a female valve which may also function as a handle for manipulation of the catheter 100. The locking valve is one obtainable from Medi-tech of Watertown, Mass. The sutures 106, 108 extend from the auxiliary catheter 104, through the single lumen of the main catheter 102, through the locking valve 110 and enlargement 112, and are secured at their free end to a respective flat paddle 114, 116. To facilitate insertion of the catheter 100, there is provided a stiffer, yet flexible hollow cannula 118 dimensioned to receive a guide wire and to be slidingly received through the interior of the main catheter 102 and auxiliary catheter 104.
The main catheter 102 generally has a uniform cylindrical cross-section along its length. On the other hand, the auxiliary catheter 104 includes a center portion 120 of generally uniform cylindrical cross-section extending between a pair of gradually tapered ends 122, 124. However, the auxiliary catheter 104 may also be of uniform cross-section along its length. The auxiliary catheter 104 is provided with a plurality of openings 126 and a centrally arranged T-hole 28. The tapered ends 122, 124 may be of different length, in particular, whereby the T-hole is not centered within the auxiliary catheter 104. Suture 106 is attached to the side wall of the auxiliary catheter 104 by passing through the T-hole 128 and looping through a pair of spaced apart pin holes (not shown) in the auxiliary catheter side wall to form a taunt loop 130. The pin holes are spaced apart slightly wider than the diameter of the T-hole 128. Suture 108 is attached to the tapered end 124 of the auxiliary catheter 104 by passing from the interior thereof through opening 126 and back to the interior through a pinhole (not shown) in the side wall of the tapered end to form a taunt loop 132.
The percutaneous introduction of the two-piece retrievable catheter 100 for the replacement of a dislodged surgically implanted T-tube will now be described with respect to FIGS. 2, 3 and 8. The catheter 100 is initially assembled for placement into the previously prepared T-tube track 134 by pulling suture 108 taunt by means of paddle 116. As shown in FIG. 2, the auxiliary catheter 104 is arranged in longitudinal alignment with the main catheter 102 with the tapered end 124 engaged with the mouth 136 of the main catheter. This arrangement of the main catheter 102 and auxiliary catheter 104 is maintained by securing the sutures 106, 108 by rotating the locking valve 110 180° using one of the paddles 114, 116 which are sized to engage the notch 138 provided on the internal hub (not shown) of the locking device. Upon rotation of the hub, the sutures 106, 108 are wrapped thereabout to secure same in a taunt condition while maintaining fluid communication between the main catheter 102 and the enlargement 112.
The main catheter 102 and auxiliary catheter 104 are stiffened to facilitate introduction by insertion of the cannula 118 through their respective hollow interiors as shown in FIG. 2. The catheter 100 is gently advanced and manipulated through the T-tube track 134 over a guide wire (not shown) until the auxiliary catheter 104 is positioned within the common bile duct as shown in FIG. 8A. The guide wire and cannula 118 are removed and the locking valve 110 rotated to release sutures 106, 108 allowing separation of the auxiliary catheter 104 from the main catheter 102 as shown in FIG. 8B. The T-hole paddle 114 is pulled causing the auxiliary catheter 104 to orient itself with its longitudinal axis approximately perpendicular to the longitudinal axis of the main catheter 102 as shown in FIG. 8C, although outer angular relationships are possible. The pulling of the T-hole suture 106 to a taunt condition will secure the auxiliary catheter in angular relationship to the main catheter 102 with the mouth 136 of the main catheter being received within or engaging the T-hole 128 of the auxiliary catheter as best shown in FIG. 3, as well as FIG. 8D. The main catheter 102 is now in fluid communication with the common bile duct through the auxiliary catheter 104. This arrangement of the main catheter 102 and auxiliary catheter 104 is maintained by placing the T-hole suture 106 in a taunt condition by securing same by means of the locking valve 110 as previously described.
One application of the catheter 100 in accordance with the present invention is for drainage of the common bile duct following surgery performed on the gallbladder such as its removal. The catheter 100 can also be utilized to flush the common bile duct or for other purposes while still inserted therein, such as the non-surgical removal of retained stones and the like from the duct to a location outside the body wall of the patient. The catheter 100 may also be used to infuse medication to dissolve the stones, as well as providing access to other internal blockages such as at the Ampulla of Vater, to stent intra hepatic obstructions, to drain bile externally and to stent or protect a duct that had been opened or dilated. In this regard, the auxiliary catheter 104 may be modified to have one tapered end 122, 124 of sufficient length to stent the Ampulla of Vater after balloon sphincteroplasty. In addition, upon laproscopic gallbladder removal or open cholecystectomy, the catheter 100 may be placed within the cystic duct and the auxiliary catheter 104 arranged bridging the common hepatic duct and common bile duct to withdraw bile fluid, remove stones and to dilate narrow passages while keeping the ducts patent. The catheter 100 may be removed from the body of the patient by reversing the above-described procedure.
Referring now to FIGS. 4A-4D, there is disclosed various embodiments of the joining of the mouth 136 of the main catheter 102 to the T-hole 128 of the auxiliary catheter 104. In FIG. 4A, the main catheter 102 is provided with a blunt mouth 136 to engage a circular T-hole 128 within the auxiliary catheter 104. In FIG. 4B, the mouth 136 of the main catheter 102 has been rounded to provide a better conforming fit with the T-hole 128 which has been formed with tapered side walls as indicated by the dashed lines. In FIG. 4C, the T-hole 128 has a square shape to engage in a more conforming fit with the blunt mouth 136 of the main catheter 102. In FIG. 4D, the mouth 136 of the main catheter 102 has been tapered to engage the T-hole 128 which has been formed by tapered side walls of the auxiliary catheter 104 as indicated by the dashed lines. It is to be understood that it is not a requirement that a fluid tight seal be created between the mouth 136 of the main catheter 102 and the T-hole 128 of the auxiliary catheter 104. In this regard, bile from the common bile duct will take the path of least resistance. In the event of blockage of the common bile duct below the position of the auxiliary catheter 104, the bile will back up and flow outside the patient's body through the catheter 100 irrespective of providing a fluid tight seal between the mouth 136 of the main catheter and T-hole 128 of the auxiliary catheter.
The auxiliary catheter 104 can also be constructed in accordance with the embodiment disclosed in FIG. 5. As shown, the auxiliary catheter 104 is provided with a longitudinal slit 140 within its side wall extending from the T-hole 128 to the edge of the tapered end 124. The slit 140 enables the T-hole suture 106 to be received within the hollow interior of the auxiliary catheter 104 as opposed to being exposed as shown in FIG. 1. As the auxiliary catheter 104 is being manipulated from its position shown in FIG. 8A to its position shown in FIG. 8D, the T-hole suture 106 slides through the slit 140 from the tapered end 124 until it reaches the T-hole 128. One advantage of the auxiliary catheter 104 in accordance with the FIG. 5 embodiment, is the maintaining of the T-hole suture 106 inside the auxiliary catheter 104 during placement. This arrangement may facilitate placement of the auxiliary catheter 104 under certain conditions where obstructions or narrow passages are encountered. However, the auxiliary catheter 104 constructed in accordance with the FIG. 1 embodiment is preferred as it possess greater mechanical strength as a result of the absence of the slit 140.
Referring to FIG. 6, another embodiment of an auxiliary catheter 142 is shown in the nature of a T-loop. The auxiliary catheter 142 is provided with a short catheter segment 144 and a lengthened catheter segment 146. A loop suture 148 extends from T-hole 128, through lengthened catheter segment 146, out on opening 150 at the end of the lengthened catheter segment and through a pinhole (not shown) remote therefrom formed in the side wall of the lengthened catheter segment. The loop suture 148 returns through the T-hole 128 and through the main catheter 102 to an additional paddle (not shown). The lengthened catheter segment 146 is initially arranged in longitudinal alignment with the short catheter segment 144 for placement within the common bile duct. After arrangement of the auxiliary catheter 142 in its generally perpendicular or other angular relationship with the main catheter 102 as previously described, the loop suture 148 is brought into a taunt condition by pulling the additional paddle to form a substantially closed loop. The resulting loop provides the catheter 100 with greater retentive ability within the common bile duct which is particularly useful in obese patients.
The paddles 114, 116 as shown in FIG. 1 extend hanging exterior to the catheter 100 and outside the body of the patient which might be considered an inconvenience. Referring to FIG. 7, there is shown a suture storage device 152 which also functions as a flush extension tube. The suture storage device 152 is constructed from a cylindrical hollow tube 154 having a male luer connection 156 at one end and a female luer connection 158 at the other. The sutures 106, 108 extend into the interior of the hollow tube 154 for storage and are terminated by metal elongated handles 160 as opposed to the previously described paddles 114, 116. The handles 160 are sized to pass through the male or female luer connections 156, 158 for use. The suture storage device 152 is connectable to the proximal portion of the catheter 100 by means of a female luer connection 162 attached to the locking valve 110. It should be appreciated that other forms of connection between the suture storage device 152 and the catheter 100 may be used.
In addition to the suture storage device 152 functioning to store the sutures 106, 108, the device may function as a flush extension tube. In this regard, a syringe 164 having a male luer connection 166 may be used for injecting medicine, flushing fluids and the like through the suture storage device 152 upon connection to the female luer connection 158. In addition, a stop cock 168 having a male luer connection 170 may be attached to the female luer connector 158 of the suture storage device 152.
Referring to FIGS. 9 and 10, two additional embodiments for attaching the T-hole suture 106 to the auxiliary catheter 104 are disclosed. As shown in FIG. 9, the T-hole suture 106 passes through the T-hole 128 and through a plurality of pinholes (not shown) within the side wall of the auxiliary catheter 104 in the manner shown. In particular, the T-hole suture 106 forms an outer loop 172 on either side of the T-hole 128 as the suture passes through the sidewall of the auxiliary catheter 104. The T-hole suture 106 continues through the interior of the auxiliary catheter 104 and outwardly through a pair of spaced-apart pinholes (not shown) to form an outer loop 174 opposite the T-hole 128.
In the embodiment shown in FIG. 10, the T-hole suture 106 also forms an outer loop 176 on either side of the T-hole 128. As shown, the outer loop 176 has a greater length than the outer loop 172 shown in FIG. 9. The greater length of the outer loop 176 is achieved by passing the T-hole suture 106 through the sidewall of the auxiliary catheter 104 at a location further removed from the initial exit pinhole than that as previously described with respect to FIG. 9. The T-hole suture 106 forms an inner loop 178 opposite the T-hole 128 within the interior of the auxiliary catheter 104 as indicated by the dashed lines. These latter two embodiments for attaching the T-hole suture 106 to the auxiliary catheter 104 are contemplated as providing a more stable and secure attachment of the auxiliary catheter to the main catheter 102 at the desired angular relationship over the previously described embodiment with respect to FIG. 1.
Although the invention herein has been described with references to particular embodiments, it is to be understood that the embodiments are merely illustrative of the principles and application of the present invention. It is therefore to be understood that numerous modifications may be made to the embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the claims. | A retrievable two piece catheter for percutaneous insertion into the common bile duct or similar vessel or canal of a patient is disclosed. The catheter is introduced as a single unit over a cannula and then formed in-situ within the duct into a T-tube configuration. Two sutures threaded through a main catheter are attached to a shorter distal auxiliary catheter, one in the center of the auxiliary catheter and one at an end thereof. After the two piece catheter has been inserted to the desired location and the cannula removed, the sutures are manipulated to maneuver the auxiliary catheter until it lies generally perpendicular to the elongated main catheter to thereby form the T-tube in fluid communication with each other. A suture-locking device provides self-retaining characteristics and the T-tube catheter can be easily retrieved, repositioned or exchanged. The T-tube catheter can be modified within a long distal limb to stent the Ampulla of Vater after balloon sphincteroplasty. A second type of two piece catheter with a self-retaining loop can be used as an internal biliary drainage catheter when treating distal common bile duct obstructions. | 0 |
This is a division of application Ser. No. 07/941,884, filed on Sep. 8, 1992, now U.S. Pat. No. 5,208,339.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to novel nitrogen-containing perfluoroalkanoyl peroxides and a method for the production thereof. More particularly, this invention relates to nitrogen-containing perfluoroalkanoyl peroxides suitable for use as a polymerization initiator for fluorine-containing monomers, as a reagent for introducing nitrogen-containing perfluoroalkyl groups, and as a raw material for perfluoro-tertiary diamines which are useful as heat transfer media or solvents and to a method for highly efficient production of the nitrogen-containing perfluoroalkanoyl peroxides from perfluoro(dialkylamino group-substituted carboxylic acid fluorides).
2. Prior Art Statement
It is known that perfluoroalkanoyl peroxides are useful as polymerization initiators for the production of fluorine-containing polymers (Japanese Patent Public Disclosure SHO 49(1974)-10290). It is also known that many perfluoroalkyl group-containing compounds exhibit useful qualities such as surface activity, lubricity, and physiological activity. As methods for producing perfluoroalkyl group-containing compounds, those using perfluoroalkyl iodides ["Journal of Fluorine Chemistry", Vol. 22, page 541 (1983)] and FITS reagents ["Journal of Synthetic Organic Chemistry, Japan", Vol. 41, page 251 (1983)] and those by perfluoroalkylation using fluorine-containing alkanoyl peroxides ["Journal of Synthetic Organic Chemistry, Japan", Vol. 46, page 1205 (1988)] have been proposed to date.
However, the only perfluoroalkanoyl peroxides available up to now have been: (1) perfluoroalkanoyl peroxides produced from a perfluorocarboxylic acid chloride as a raw material and (2) perfluoroalkanoyl peroxides produced from a perfluorocarboxylic acid fluoride containing an oxygen atom in the perfluoroalkyl group thereof by oligomerizing reaction of hexafluoropropene oxide, this latter group of perfluoroalkanoyl peroxides consisting of (a) bis(perfluoro-2-methyl-3-oxahexanoyl) peroxides [referred to in the Journal of Organic Chemistry, Vol. 47, page 2009 (1982)] and (b) bis(perfluoro-2,5-dimethyl-3,6-dioxanonanoyl) peroxide, bis(perfluoro-2,5,8-trimethyl-3,6,9-trioxadecanoyl) peroxide and bis(perfluoro-2,5,8,11,14-pentamethyl-3,6,9,12,15-pentaoxaoctadecanoyl) peroxides [all three of which are referred to in the proceeding of the 15th Symposium on Flourine Chemistry, 0-29 held on Oct. 22 and 23, 1990 in Tokyo]. In the circumstances, a need has arisen for perfluoroalkanoyl peroxides suitable for use in various industrial applications.
SUMMARY OF THE INVENTION
This invention was accomplished in response to this need and has as its object to provide novel nitrogen-containing perfluoroalkanoyl peroxides which are useful in a wide range of applications requiring, for example, a polymerization initiator for fluorine-containing monomers or a reagent for the introduction of nitrogen-containing perfluoroalkyl groups into compounds, and also as a heat transfer medium and a solvent.
The inventors conducted a study for achieving this object. As a result, they have found that novel nitrogen-containing perfluoroalkanoyl peroxides are obtained in a relatively high yield by using as a raw material a nitrogen-containing perfluorocarboxylic acid fluoride and oxidizing this raw material to form a peroxide bond therein and that these nitrogen-containing perfluoralkanoyl peroxides can be utilized in the same applications as the conventional perfluoroalkanoyl peroxides. This invention has been completed on the basis of this finding.
To be specific, this invention relates to a nitrogen-containing perfluoralkyanoyl peroxide represented by the formula (I): ##STR3## wherein Rf 1 and Rf 2 independently stand for a perfluoroalkyl group of 1 to 5 carbon atoms, provided that Rf 1 and Rf 2 are joined to each other in one of the three patterns, 1) direct union, 2) union through the medium of a an oxygen atom or 3) union through the medium of a nitrogen atom, to form one of three rings, i.e. five-membered ring, six-membered ring or seven-membered ring, and Rf 3 stand for a perfluoroalkyl group of 1 to 3 carbon atoms.
The nitrogen-containing perfluoroalkanoyl peroxide of this invention is provided by a method which comprises oxidizing a perfluoro(dialkylamino group-substituted carboxylic acid fluoride) represented by the formula (II): ##STR4## wherein Rf 1 , Rf 2 , and Rf 3 have the same meanings as defined above.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The nitrogen-containing perfluoroalkanoyl peroxides of this invention which are represented by the aforementioned general formula are novel compounds which have not been reported in the literature. Concrete examples of the perfluorodialkylamino group, ##STR5## in the general formula are shown below.
In the following formulas, each of n and m stands for an integer in the range between 1 and 5. ##STR6##
The nitrogen-containing perfluoroalkanoyl peroxide of this invention which is represented by the general formula (I) is produced by the method of this invention described below. As the raw material, a perfluoro(dialkylamino group-substituted carboxylic acid fluoride) represented by the general formula (II) is used. This is easily produced by subjecting an ester or a halogenide of a corresponding dialkylamino group-substituted carboxylic acid to electrolytic fluorination in hydrogen fluoride.
The nitrogen-containing perfluoralkanoyl peroxide which is represented by the formula (I) is produced by oxidizing the perfluoro(dialkylamino group-substituted carboxylic acid fluoride). Two methods are available for effecting the oxidation. In the first method the oxidation is effected with hydrogen peroxide in the presence of at least one alkali selected from among sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, and potassium hydrogen carbonate and in the second method it is effected by the use of at least on alkali metal peroxide or alkaline earth metal peroxide selected from among potassium peroxide, sodium peroxide, lithium peroxide and barium peroxide.
In the first method, the molar ratio of an acid fluoride, hydrogen peroxide, and an alkaline metal salt to be used for the reaction is generally in the range of 1:0.3-20:0.3-10, preferably 1:0.5-10:0.5-7. In the second method, the molar ratio of an acid fluoride and an alkali metal peroxide or alkaline earth metal peroxide is generally in the range of 1:0.3-20, preferably 1:0.5-15. The yield in which the nitrogen-containing perfluoroalkanoyl peroxide aimed at is produced is unduly low if the molar ratio of hydrogen peroxide or that of the alkali metal salt used in the first method or the molar ratio of the alkali metal peroxide or that of the alkaline earth metal peroxide used in the second method relative to the acid fluoride as the raw material is unduly high. If this molar ratio is unduly low, the reaction time is elongated and the yield of the nitrogen-containing perfluoroalkanoyl peroxide is also lowered. The reaction temperature and the reaction time are generally selected in the ranges between -20° C. and +40° C. and between 0.5 and 8 hours. Since these reaction conditions are variable with the kinds of raw material and reagent for reaction, the molar ratio of the raw material to the reagent for reaction, and the method for synthesis of the peroxide bond, they are desired to be suitably selected in consideration of the yield of the product aimed at.
In the method of this invention, the reaction is preferably carried out in a fluorinated hydrocarbon type solvent such as 1,1,2-trichloro-1,2,2-trifluoroethane or perfluorooctane because this enables the produced nitrogen-containing perfluoroalkanoyl peroxide to be handled safely and also enables the peroxide to be handled easily in the synthesis reaction in which it is used.
The nitrogen-containing perfluoroalkanoyl peroxide produced as described above are novel compounds which have not been reported in the literature. The nitrogen-containing perfluorodialkyl chain of these compounds exhibits strong hydrophobicity and lipophobicity. The nitrogen-containing perfluoroalkanoyl peroxides are therefore useful as polymerization initiators for such electron attractive monomers as tetrafluoroethylene, vinyl chloride and hexafluoropropane. They can also be used advantageously as fluoroalkylating agents of electron excessive aromatic compounds such as benzene and pyrrole necessary for the production of useful compounds which take advantage of the characteristic properties of the nitrogen-containing perfluoroalkyl group.
They can also advantageously by used as a polymerization initiator for fluorine-containing monomers as a reagent for introduction of a nitrogen-containing perfluoroalkyl group in compounds, and as a raw material for perfluoro-tertiary diamines which are useful as heat transfer media or solvents.
This invention will now be described more specifically below with reference to working examples. It should be noted, however, that this invention is not limited in any sense by these examples.
EXAMPLE 1
First, perfluoro(3-morpholinopropionic acid fluoride) was synthesized by subjecting methyl 3-morpholinopropionate to electrolytic fluorination and then purified by distillation.
In a three-neck flask, 50 ml of 1,1,2-trichloro-2,2,1-trifluoroethane (CF 2 ClCClF 2 ) and 10 ml of an aqueous 3M sodium hydroxide solution (containing about 15 mmols of NaOH) and 2 ml of an aqueous 30 wt % hydrogen peroxide solution (containing about 20 mmols of H 2 O 2 ) added thereto were cooled to -15° C. To the resultant cooled mixture, 15.0 mmols of perfluoro(3-morpholinopropionic acid fluoride) 60.0% in purity was added piecemeal under stirring. The reaction mixture consequently obtained was further stirred at 0° C. for 25 minutes to complete the reaction. After the reaction was completed, the produced solution was washed three times with a saturated aqueous solution of sodium hydrogen carbonate, further washed several times with ice water, and dried with anhydrous sodium sulfate.
The amount of the produced peroxide was found by iodometric analysis to be 4.2 mmols and the yield thereof to be 56% (mol yield based on perfluoro acid fluoride). By chemical analysis, the produced compound was identified to be bis(perfluoro-3-morpholinopropionyl) peroxide having a 10-hour half period temperature of 24.1° C. and an active oxygen content of 2.1%.
The bis(perfluoro-3-morpholinopropionyl) peroxide was a novel peroxide which was colorless and transparent in CF 2 ClCFCl 2 and was stable at low temperatures (at -20° C.) for more than one month.
The 19 F-NMR data (chemical shift; 19 F-NMR based on CFCl 3 in a CDCl 3 solvent) of this compound are shown below. ##STR7##
The kinetic constants of thermal decomposition at varying temperatures and the activation energy in CF 2 ClCFCl 2 are shown in Table 1.
TABLE 1______________________________________Temperature Activation energy(°C.) k × 10.sup.5 (s.sup.-1) (kcal/mol)______________________________________30 3.82 ± 0.0535 10.6 ± 0.0540 16.3 ± 0.05 25.7 ± 1.244 25.9 ± 0.05______________________________________
The identify of this compound was confirmed by the reaction of the following Referential Example 1.
REFERENTIAL EXAMPLE 1
When 69.9 g of a CF 2 ClCFCl 2 solution containing 4.20 mmols of the bis(perfluoro-3-morpholinopropionyl) peroxide obtained in Example 1 was heated and refluxed overnight, then distilled in a rotary evaporator to expel the solvent and purified by the process of sublimination, 1.42 g of a white solid substance was obtained which exhibited a melting point of 51.0°-52.5° C. and a boiling point of 190.0°-191.0° C. This substance, on analysis by 19 NMR, IR, and MS, was identified to be perfluoro(1,4-dimorpholinobutane) (yield 51%) obtained in the form of a coupling product via the process of decomposition of the peroxide mentioned above.
EXAMPLE 2
The procedure of Example 1 was faithfully repeated, except that perfluoro(3-dimethylaminopropionic acid fluoride) was used in the place of the perfluoro(3-morpholinopropionic acid fluoride. The perfluoro(3-dimethylaminopropionic acid fluoride) (purity 81.7% and content 30.4 mmols) was synthesized by subjected methyl 3-dimethylamino-propionate to electrolytic fluorination and then purified before use.
The compound, consequently obtained when analyzed in the same manner as in Example 1, was found to be bis(perfluoro-3-dimethylaminopropionyl) peroxide having a 10-hour half period temperature of 21.3° C. and an active oxygen content of 2.7%. The amount of this compound produced was found to be 12.2 mmols and the yield thereof to be 80%.
The 19 F-NMR data of this compound are shown below. ##STR8##
The kinetic constants of thermal decomposition at different temperatures and the activation energy in CF 2 ClCFCl 2 are shown in Table 2.
TABLE 2______________________________________Temperature Activation energy(°C.) k × 10.sup.5 (s.sup.-1) (kcal/mol)______________________________________30 5.36 + 0.1435 9.33 ± 0.0640 17.2 ± 0.02 20.7 ± 0.248 34.4 ± 0.61______________________________________
EXAMPLE 3
The procedure of Example 1 was faithfully repeated, except that perfluoro(3-pyrrolidinopropionic acid fluoride) was used in the place of the perfluoro(3-morpholinopropionic acid fluoride). The perfluoro(3-pyrrolidinopropionic acid fluoride) (purity 81.6% and content 16.2 mmols) was synthesized by subjecting methyl 3-pyrrolidinopropionate to electrolytic fluorination and was purified before use.
The compound consequently obtained, when analyzed in the same manner as in Example 1, was identified to be bis(perfluoro-3-pyrrolidinopropionyl) peroxide having a kinetic constant, k, of 6.15×10 -4 (s -1 ) at 48° C. and an active oxygen content of 2.2%. The amount of the product was found to be 5.42 mmols and the yield thereof to be 67%.
The identity of this compound was confirmed by the reaction shown in the following Referential Example 2.
REFERENTIAL EXAMPLE 2
When 59.9 g of a CF 2 ClCFCl 2 solution containing 2.64 mmols of the peroxide obtained in the Example 3 was refluxed overnight, distilled to expel the solvent in the same manner as in Referential Example 1, and then purified with GC, 1.06 g of a colorless transparent solution was obtained which exhibited a melting point of 29.5-31.0° C. and a boiling point of 187.5°-188.5° C. The solution, on analysis by 19 F-NMR, IR, and MS, was identified to be a perfluoro(1,4-dipyrrolidinobutane) (yield 64%) obtained in the form of a coupling product through the process of decomposition of the peroxide.
EXAMPLE 4
The procedure of Example 1 was faithfully repeated, except that perfluoro(3-piperidinopropionic acid fluoride) was used in the place of the perfluoro(3-morpholinopropionic acid fluoride). The perfluoro(3-piperidinopropionic acid fluoride) (purity 81.7% and content 34.2 mmols) was synthesized by subsjecting methyl 3-piperidinopropionate to electrolytic fluorination and purified before use.
The compound, when analyzed in the same manner as in Example 1, was found to be bis(perfluoro-3-piperidinopropionyl) peroxide having a 10-hour half period temperature of 22.2° C. and an active oxygen content of 2.0%. The amount of this compound produced was found to be 34.2 mmols and the yield thereof to be 60%.
The kinetic constants of thermal decomposition at different temperatures and the activation energy in CF 2 ClCFCl 2 are shown in Table 3.
TABLE 3______________________________________Temperature Activation energy(°C.) k × 10.sup.5 (s.sup.-1) (kcal/mol)______________________________________30 5.69 ± 0.0735 6.91 ± 0.1740 15.9 ± 0.19 23.4 ± 0.248 25.4 ± 0.49______________________________________
EXAMPLE 5
The procedure of Example 1 was faithfully repeated, except that perfluoro(morpholinoacetyl fluoride) was used in place of the perfluoro(3-morpholinopropionic acid fluoride). The perfluoro(morpholinoacetyl fluoride) (purity 91.8% and content 15.1 mmols) was synthesized by subjecting methyl morpholinoacetic acid to electrolytic fluorination and purified before use.
The compound consequently obtained, when analyzed in the same manner as in Example 1, was identified to be bis(perfluoro-morpholinoacetyl) peroxide having an active oxygen content of 2.5%. The amount of the product was found to be 3.6 mmols and the yield thereof to be 48%.
EXAMPLE 6
The procedure of Example 1 was faithfully repeated, except that perfluoro(3-dimethylaminoisobutyric acid fluoride) was used in place of the perfluoro(3-morpholinopropionic acid fluoride). The perfluoro(3-dimethylaminoisobutyric acid fluoride) (purity 79.7% and content 15.3 mmols) was synthesized by subjecting methyl 3-dimethylaminoisobutyrate to electrolytic fluorination and purified before use.
The compound consequently obtained, when analyzed in the same manner as in Example 1, was identified to be bis(perfluoro-3-dimethylaminoisobutyryl) peroxide having an active oxygen content of 2.3%. The amount of the compound obtained was found to be 3.6 mmols and the yield thereof to be 48%. | A nitrogen-containing perfluoroalkanoyl peroxide is provided which is represented by the formula: ##STR1## wherein Rf 1 and Rf 2 independently stand for an alkyl group of 1 to 5 carbon atoms, provided that Rf 1 and Rf 2 are joined to each other in one of the three patterns of union, 1) direct union, 2) union through the medium of an oxygen atom or 3) union through the medium of a nitrogen atom to form one of the three rings, i.e. five membered ring, six-membered ring or seven-membered ring. The nitrogen-containing perfluoroalkanoyl peroxide is produced by a method which comprises oxidizing a compound represented by the following formula: ##STR2## | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The field of art to which the invention pertains includes the field of spool holder apparatus for sewing machines, particularly, a spool holder apparatus for securing a spool of thread in a horizontal plane on a sewing machine head.
2. Description of the Prior Art
Conventional thread spool holder spindles are positioned so that the spool of thread can be mounted on the sewing machine head in a vertical position and is freely moveable along the vertical axis of the spindle. In such arrangements the thread is normally wound on the spool in continuous planes perpendicular to the axis of the spool. As the thread is unwound from the spool, the proper tension is provided by the tension unit of the machine. However, when the thread is wound on a light weight spool, such as styrofoam, it is found that the spool and the thread move along the vertical axis of the spindle causing tension changes in the thread which cannot be compensated for in the sewing machine tension unit. Thus, it has been found that the thread will continuously break causing large amounts of down time for the sewing machine operator. Additionally, where the thread is wound on a spool in planes which intersect the axis of the spool at varying angles, there is a continuous tension change on the thread which cannot be compensated for by the sewing machine tension unit. These tension changes also result in thread breakage and the resultant down time of the machine.
The present invention provides apparatus for mounting a spool of thread in a horizontal plane minimizing tension changes as the thread is fed from the spool to the tension unit of the sewing machine. The present invention enables all types of thread and spools to continuously flow to the tension unit of the sewing machine without restriction. Thread tension changes are minimized and the apparatus can be used in combination with all types of sewing machines.
SUMMARY OF THE INVENTION
Apparatus for positioning a spool of thread in a generally horizontal plane on a sewing machine head. A base has a pair of vertically extending arms extending therefrom. A spool holder is formed of an elongated member secured at its ends to said arms, respectively, and has an axis perpendicular to the plane of the arms. Securing means are provided for attaching the base to the machine head.
The advantages of this invention, both as to its construction and mode of operation, will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating the spool holder apparatus mounted on a sewing machine;
FIG. 2 is an exploded perspective view of the spool holder apparatus of the invention; and
FIGS. 3(a) and 3(b) schematically illustrated alternative mounting positions on various types of sewing machines.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, there is shown in FIG. 1 a sewing machine head 12 of conventional design. Mounted on the sewing machine head top surface 14 is a spool holder apparatus 16 constructed in accordance with the principles of the invention. The spool holder apparatus 16 is mounted on the head top surface 14 intermediate the balance wheel end 18 and the thread take up end 22 of the machine. The spool holder apparatus 16 is normally mounted adjacent the vertical spindle 24 which can be retained on the sewing machine head for future use if desired.
Referring now to FIG. 2 the spool holder apparatus 16 is shown in greater detail and comprises a horizontal base plate 26 formed in a horizontal plane and having a pair of vertically extending arms 28 and 32 extending upwardly from either end of the base plate. A pair of angled slots 34 and 36 are formed in the vertically extending arms and extend from the top surface of the arms at an angle in a direction toward the rear edge 38 of the base plate 26 and the arms 32 and 34.
A mounting plate 40 is normally secured to the top surface 14 of the sewing machine head in a manner which will be described in greater detail hereinafter. A spring member 42 is integrally formed at one end with the front edge 44 of the horizontal base plate 26 and at its other end to the rear edge of the mounting plate 40. The spring member 42 extends downwardly to form an acute angle with the horizontal base plate 26 and the mounting plate 40 and is joined thereto at spring member 42 curved surfaces 46 and 48, respectively.
While the mounting plate 40 could be fastened by means of screws to the machine head top surface 14, it has been found that a preferable technique is to permanently affix a velcro pad 52 to the machine head top surface 14 by means of an adhesive layer 54. Normally the velcro pad 52 has the same dimensions as the bottom surface of the mounting plate 40. Then the spool holder apparatus can be attached to or removed from the sewing machine head 12 at will, as the bottom surface of the mounting plate 40 adheres to the velcro pad 52.
A spool holder 56 is removably mounted in the slots 34 and 36 of the vertically extending arms 28 and 32, respectively. The spool holder is formed of an enlarged central rod 58 whose length is normally greater than the length of a spool which is positioned thereon. In addition, the diameter of the rod 58 is normally less than the opening in the spool enabling the spool to freely rotate thereon. Extending along the axis of the rod 58 from opposite ends thereof are a pair of reduced diameter tips 62 and 64, respectively. A pair of enlarged collars 66 and 68 are attached to the free ends of each of the tips 62 and 64, respectively. The dimension of the spool holder 56 is such that the tips 62 and 64 will be positioned in the slots 34 and 36, respectively, when the spool holder is positioned between the vertically extending arms 28 and 32. Simultaneously, the collars 66 and 68 will be on the exterior side surface of the vertically extending arms 28 and 32, respectively.
The spool of thread 72 having a central spool cylinder 74 is normally positioned on the cylindrical rod 58 prior to mounting the spool on the spool holder 56. Referring again to FIG. 1, once the spool 72 is positioned on the spool holder 56, the thread then can be fed to a thread guide 76 positioned on the sewing machine head adjacent the thread take up end 22. Then, as is conventional, the thread is fed through an upper tension unit 78 to the thread take up 82. The thread 84 wound on the spool cylinder 74 intersects the axis of the spool 74 at continuously varying angles. As can be seen in FIG. 3(a), the spool holder apparatus 16 is positioned so that the axis of the spool 74 is substantially perpendicular to the thread feed axis as the thread 84 is unwound from the spool 74 and is fed to the thread guide. This positioning of the thread spool 74 minimizes tension changes in the thread as it feeds off the spool 74 in various changing directions due to the angular winding of the thread on the spool. FIG. 3(b) illustrates a different mounting position of the spool holder apparatus where a thread guide 88 is positioned in the top center of the machine head.
It should be noted that the spring member 42 connecting the mounting plate 40 and the horizontal base plate 26 enables the spool holder to flex sufficiently as the thread is fed off the spool minimizing thread breakage.
While the spool holder 56 has been shown as being removable from the vertically extending arms 28 and 32, it should be understood that one end of the spool holder 56 could be pivotably attached to one of the vertically extending arms and the other end of the spool holder could be made removable for changing spools of thread. | Spool holder apparatus for positioning a spool of thread in a generally horizontal plane on a sewing machine head. The spool holder apparatus base has a pair of vertically extending arms extending therefrom. A spool holder is formed of an elongated member secured at its ends to said vertically extending arms, respectively, and has an axis perpendicular to said arms. Securing means are provided for attaching the base to the machine. | 3 |
BACKGROUND TO THE INVENTION
[0001] The invention relates to protective covers and more particularly but not exclusively to protective covers for protecting moving parts in a mechanism of motor vehicles.
SUMMARY OF THE INVENTION
[0002] According to the invention, there is provided a protective cover for a motor vehicle joint, the cover having a deformable structure defining an interior space closed at both ends and including vent means coupled to the interior space, the vent means including a vent element adapted to allow fluid flow thereacross whilst stopping contaminant and/ or water entering into the interior space whereby excess fluid pressure within the interior can be reduced by fluid evacuation and aspiration through the vent means.
[0003] Typically, the fluid will be air.
[0004] Protective covers embodying the invention will now be described, by way of example with reference to the accompanying diagrammatic drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] [0005]FIG. 1 is a schematic front elevation of a steering arrangement with protective covers;
[0006] [0006]FIG. 2 is a schematic front elevation of the steering arrangement depicted in FIG. 1 turned to the right;
[0007] [0007]FIG. 3 is a schematic front elevation of the steering arrangement depicted in FIGS. 1 and 2 turned to the right and subject to suspension articulation;
[0008] [0008]FIG. 4 is a schematic front elevation of a transmission arrangement with protective covers;
[0009] [0009]FIG. 5 is a cross-section through one of the protective covers embodying the invention;
[0010] [0010]FIG. 6 is an enlarged view of the portion of FIG. 5 shown at II; and,
[0011] [0011]FIG. 7 is an end view of part of a connector shown in FIG. 6, looking in the direction of the arrow III;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The protective cover arrangement 10 shown in FIGS. 5 and 6 comprises a small diameter sealing collar 12 at one end and a larger diameter sealing collar 14 at the opposite end, with a plurality of bellows turns 16 integrally extending between the two ends. In use, the two sealing collars are attached to two relatively movable parts of a mechanism (not shown) which is to be protected in a motor vehicle. The cover 10 protects the mechanism from ingress of water, dirt and other contamination.
[0013] In one particular application of the protective cover shown in FIGS. 1 to 3 , two of them are respectively mounted to protect the ends of a steering rack of a steering arrangement 100 in a vehicle. Thus, the steering arrangement 100 may comprise a steering box 104 operated directly by the driver's steering wheel 105 or through the intermediary of a power steering arrangement. A steering rack extends outwardly in opposite directions from each side of the steering box 104 and is moved axially in one or the other direction by the steering box in response to steering action by the driver. The opposite ends of the rack are connected to turn the steerable wheels 103 of the vehicle. In use, a cover 110 extends from one side of the steering box 104 , with its larger diameter fixing collar 114 being secured to the steering box 104 where the steering rack extends outwardly therefrom. The smaller diameter collar 112 of the cover 110 is secured to the distal end of the rack.
[0014] At the opposite side of the steering box 104 , from which the second end of the rack protrudes, a second cover 110 is secured, with its smaller diameter collar 112 fixed to that distal end of the steering rack.
[0015] The two protective covers 110 thus protect the two end portions of the rack and the bellows flexibly accommodate axial movement.
[0016] As the steering rack moves to and fro, in order to carry out desired steering action, the two protective covers 110 will be alternately compressed and expanded as will now be explained in more detail.
[0017] It will be noted from FIG. 1 that the steering arrangement depicted has wheels 103 in a straight-ahead configuration. Thus, the steering box 104 is not displacing the steering rack either to the right or the left. In such circumstances, the protective covers 110 are not generally deformed (that is, not compressed or stretched), and so the interior volumes of these covers 110 will be substantially at their designed pressure, normally atmospheric. Thus, these covers 110 should not rupture, create noise problems or alter the function of the underlying steering mechanism.
[0018] In FIG. 2, the steering arrangement of FIG. 1 has been turned to the right. Thus, cover 110 a is compressed whilst cover 110 b is expanded. The covers 110 are sealed by collars 112 , 114 at each end. Therefore, the compressed cover 110 a would normally be at an elevated pressure whilst the expanded cover 110 b would be at a reduced pressure.
[0019] Similarly, in FIG. 3, the covers 110 are respectively further expanded ( 110 b ) and compressed ( 110 a ) by suspension 111 movement to accommodate bumps as the vehicle including the steering arrangement moves.
[0020] [0020]FIG. 4 shows how a similar problem can arise with a drive shaft or transmission arrangement. A drive shaft 201 extends between an outboard joint 230 and an inboard joint 231 . The outboard joint 230 is supported by a suspension 233 and the wheel 234 . In such circumstances, the protective covers 232 can be angled and the protective cover 236 can be compressed or expanded. The pressure variation appears only in the inboard joint 231 .
[0021] It is necessary to accommodate the resultant changes in pressure in the protective covers. If this is not done, excessive pressure may rupture the protective covers. One known way of dealing with this problem, is to interconnect the interiors of the two covers used at respective ends of a steering rack. In this way, when one cover is contracted by movement of the steering rack, the increased pressure within the now deformed cover is transmitted to the interior of the other cover which will at the same time be expanded.
[0022] In accordance with a feature of the covers being described, this interconnection between the two bellows at opposite ends of the steering rack is removed in order to allow easier assembly and to reduce costs.
[0023] Referring to FIG. 5, the bellows 10 there shown has a vent arrangement 20 at one end. The vent 20 is L-shaped in form, comprising a relatively long hollow tubular part 22 and a relatively short hollow tubular part 24 . Each part 22 , 24 has an open end 22 A, 24 A. As shown in FIGS. 5 and 6, the vent 20 is secured in position on the cover 10 so that the end 24 A is attached to the wall of the bellows adjacent the larger diameter collar 14 and with the hollow interior of the part 24 thus open to the interior 25 of the cover 10 . The part 24 of the vent 20 thus extends radially of the major axis of the cover 10 and the part 22 of the connector extends in an axial direction.
[0024] Such a bellows 10 can therefore be mounted at one end of a steering rack (for example, as shown in FIGS. 1 to 3 ) or at one end of a drive shaft (for example, as shown in FIG. 4). A similar bellows would then be mounted at the other end of the steering rack or drive shaft.
[0025] The vent 20 of the bellows 10 at the other end of the rack or drive shaft would be mounted on the bellows in the same way.
[0026] Each vent 20 is very firmly secured to the bellows 10 . A welding operation can be used to form a very strong welded bond between the material of the vent 20 and the material of the bellows 10 . In addition, a mechanical bond is formed between the vent 20 and the material of the bellows 10 where it enters the end 24 A of the vent 20 . However, the vent 20 could be mounted on the bellows 10 by a glueing operation.
[0027] It will be appreciated that the vent 20 can be situated at any desired position on the external wall of the bellows.
[0028] At the open end of 22 a of each vent 20 , a vent element 21 is located. The purpose of this element 21 is to allow air to pass into and out of the bellows 10 whilst preventing ingress of contaminants and water to the interior volume 25 .
[0029] In effect, the vent 20 and the vent element 21 adjust the volume of air within the interior so that it is consistent with air pressure. In such circumstances, the vent element 21 acts as a filter to prevent transfer of contaminants, such as grit, grease, etc. and water, into the interior, allowing relatively free movement of air to adjust the volume of the interior 25 as the cover 10 is deformed in extension or compression. In such circumstances, the vent 20 prevents excessive fluid (air) pressure build-up in the interior 25 and will normally maintain that interior at about atmospheric pressure. Furthermore, with a lubricant inside the protective cover 10 it will be understood this lubricant is prevented from escaping and so facilitating continued lubrication of a protected mechanism.
[0030] The vent element 21 can be formed of a Teflon (Trade Mark) material of calibrated porosity to allow air movement but to prevent contaminants or water entering the interior 25 . Clearly, the specific material used is dependent upon the installation requirements; suitable other materials may be used.
[0031] The vent 20 and vent element 21 remove the necessity of a connecting tube between the pair of protective covers 10 . Thus, installation and maintenance of the cover 10 is made less difficult and costly.
[0032] In order to extend the operational life of vent element 21 , it will be understood that at least a proportion of any contaminants and/or water will be removed from the element 21 as air or fluids flow out of the interior 25 .
[0033] This vent works also to avoid any variation of pressure due to external temperature or atmospheric pressure variation. | A protective cover which is generally in the form of a flexible bellows construction secured at each end by collars in order to define an interior space includes vent means. Thus, when the cover is deformed, the volume within the interior is altered by aspiration or evacuation through the vent means. The vent means includes a vent element in order to allow air or fluid transfer into and out of the interior but prevent ingress of contaminants such as grit and water to the interior. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to cardiac pacers and, more particularly, to improvements in oscillator circuits used in cardiac pacers. While the invention will be described in most detail in association with demand type pacers, the invention is applicable to all kinds of pacers having an oscillator circuit therein which establishes the normal operating rate of the pacer.
2. Description of the Prior Art
In electrical heart pacers and in particular demand type pacers, electrical stimulating pulses are delivered to the patient's heart only in the absence of natural heartbeats. Generally, the demand pacer is designed to deliver an electrical stimulating pulse to the heart at a predetermined time interval after the last natural heartbeat, and to continue to deliver stimulus pulses at a fixed rate as long as no natural heartbeats are sensed by the pacer. If a heartbeat is sensed by the pacer during the timing interval of the oscillator of the pacing device, the pacer oscillator is reset so that it starts its timing cycle over again and the pacer output is inhibited so that no stimulus pulse is delivered to the heart. The time interval between the moment when the pacer oscillator is reset and the time when it completes a timing cycle is sometimes referred to as the escape interval.
Such demand type pacers are well-known, have been miniaturized, are usually self-contained and powered by battery and are now wholly implanted within the body. It will therefore be appreciated that the packing density of circuit components in such a pacer is very high resulting in conditions which could lead to circuit malfunctions as, for example, malfunctions caused by current leakage between adjacent components or leads interconnecting components. In the past, such circuit malfunctions have caused pacers to fail in a manner resulting in a rate runaway condition which is clearly undesirable for the patient. In fact, it could be lethal.
Accordingly, a primary object of the present invention is to provide in a cardiac pacer a means for limiting the pacer operating rate to a predetermined rate which, while above the normal pacer operating rate, is still considered to be a safe pacer operating rate.
SUMMARY OF THE INVENTION
In accordance with the invention, an oscillator circuit is provided capable of use with a cardiac pacer. The oscillator includes a pulse generating network, a pulse rate network and a strobe network. The pulse generating network generates pulses at a first rate or at a second rate, the second rate being higher than the first rate. The pulse rate network, including pulse rate control means, establishes the rate at which the pulse generating network generates pulses with the pulse rate control means being normally operative to cause the pulse generating network to generate pulses at the first rate but, when the first rate exceeds the second rate, to cause the pulse generating network to generate pulses at the second rate. The strobe network establishes the beginning of each cycle of the pulse rate network.
A more complete understanding of the invention will be had from the following detailed description taken in connection with the accompanying drawings which form a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block circuit diagram of a demand cardiac pacer embodying the invention;
FIG. 1a illustrates in block form the battery power source for the pacer of FIG. 1;
FIG. 2 is a schematic circuit diagram of an oscillator circuit in accordance with the invention; and
FIGS. 3a, 3b, 4a, 4b and 5 show timing diagrams useful to explain the operation of the circuit of FIG. 2. FIGS. 3a and 3b for ease of illustration have been presented as two separate sheets of drawings which can be interconnected along a break line for viewing as a single drawing, the same being true for FIGS. 4a and 4b.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In order to lay a foundation for the detailed description, which follows hereinafter, of the operation of the oscillator of the invention shown in FIG. 2, a brief description of the demand pacer illustrated in FIG. 1 will first be given. This will be followed by a general description of the component functions and circuit operation of FIG. 2 with the specific functions of the components and circuit operation of FIG. 2 becoming more evident in the detailed description of the operation of the oscillator circuit of FIG. 2.
Brief Description of Demand Pacer of FIG. 1
As stated above, a demand pacer supplies a stimulating pulse to the heart whenever the time interval from the last heartbeat exceeds a predetermined interval, i.e., the escape interval. Otherwise, the heartbeat signal sensed by the pacer inhibits the generation of an output stimulating pulse and recycles the timing or rate network of the oscillator contained in the pacer that determines the time interval between stimulating pulses, i.e., resets the oscillator to begin a new cycle. Actually, the largest magnitude electrical signal generated by the heart activity is the QRS complex of the electrogram which corresponds to ventricular contraction, and it is the R-wave portion of this complex that is normally sensed by the demand pacer. The predetermined time or escape interval referred to is chosen to be slightly longer than the time interval naturally occurring between R-waves.
The block diagram of FIG. 1 shows the basic features of such a demand pacer. For ease of illustration, the power source V DD for the pacer shown in FIG. 1 is illustrated in FIG. 1a. The oscillator 110 and voltage converter 112 in the absence of the other blocks shown in FIG. 1 comprise a basic fixed rate or asynchronous pacer. The oscillator 110 provides a sequence of pulses on the order of 1ms in width at a nominal rate of 72 beats per minute corresponding to a time interval of 833 ms between pulses. Actually, pulse widths and rate are selected by design according to medical requirements and the numbers given are only by way of example. This is also true throughout this specification wherein typical or nominal values are indicated. It being understood that such typical or nominal values are given only by way of example.
The voltage converter 112 amplifies the voltage of the pulses to that required to properly stimulate the heart. The stimulating output pulses from the pacer are transmitted to the heart via a catheter (not shown), a flexible conductor insulated along its entire length except for a small portion at the end thereof which is lodged in the ventricle of the heart.
The addition of the amplifier 114, monostable multivibrator 116, and refractory delay network 118 converts the fixed rate pacer comprised of oscillator 110 and voltage converter 112 to a demand type pacer. In operation, the amplifier 114 senses the R-wave via the catheter and feedback path F and amplifies the signal to a level sufficient to trip the monostable multivibrator 116. The latter, in turn, activates the refractory delay network 118 and also resets the oscillator 110 to begin a new timing cycle. The refractory delay network 118, during its operative period, which is typically on the order of 250ms, blocks any other sensed signals such as those originating from electrical noise external to the body or from the T-wave in the electrogram complex from resetting the oscillator 110. Note that the amplifier 114 also senses the delivered stimulating pulse via the feedback path F. In providing a pulse, the oscillator 110 resets itself, so that the recycling action of the amplifier 114 and the refractory network 118 is redundant in this case. However, the refractory delay network 118 is activated and as before, prevents a second resetting of the oscillator 110 timing for 250 ms following an output pulse from the voltage converter 112. A demand pacer of this type is disclosed in U.S. Pat. No. 3,759,266 issued on Sept. 18, 1973.
General Description of Oscillator 110
In the following description, various logic circuit elements are referred to and prior to describing the general operation of oscillator 110, the characteristics of such logic elements will be briefly set forth. Generally, ground states represent logical zeroes and voltage levels represent logical ones on the various terminals of logic circuit elements. Logic CMOS NAND gates are well known in the art. A truth table for a CMOS NAND gate is:
______________________________________ Inputs Output A B C______________________________________ 0 0 1 0 1 1 1 0 1 1 1 0______________________________________
It is seen that if either or both input terminals is at logic 0 (low), the output terminal signal is a logic 1 (high). Only when both input terminals are high does the output terminal go low. The concept of threshold is also used in describing the action of CMOS NAND gates. A given input terminal has a negative threshold and a positive threshold. For the CMOS NAND gates they are generally nearly equal in magnitude. Accordingly, when a signal of increasing voltage (such as may appear across a charging capacitor), is applied to an input terminal of a CMOS NAND gate and crosses the positive threshold of this input, the signal is then assumed to have undergone a transition from a logic 0 to a logic 1 insofar as the effects on the gate operation are concerned. When a signal of decreasing amplitude is applied to an input terminal of a CMOS NAND gate and crosses the negative threshold of this input terminal, the signal is assumed to have undergone a transition from a logic 1 to a logic 0.
CMOS semiconductor switches (analog gates) (illustrated in FIG. 2) S1, S2, and S3 are used to discharge the oscillator 110 timing capacitors C2 and C3. A low logic level at their input terminals, S1-4, S2-7, or S3-12 turns them off. That is the resistance of the path S1-5 to S1-6, or S2-8 to S2-9, or S3-13 to S3-14 is on the order of at least 100 megohms. A high logic level at their input terminals turns them on. Then each path resistance becomes about 1000 ohms.
Referring now to FIG. 2, oscillator 110 is that portion of the pacer shown in FIG. 1 which is the concern of the present invention. The oscillator 110 comprises a strobe network shown generally at 120, a pulse rate network shown generally at 122 and a monostable multivibrator or pulse generating network shown generally at 124.
The strobe network 120 comprises a means for establishing the beginning of each cycle of the pulse rate network 122. The strobe network 120 resets the timing cycle of the oscillator 110 by causing the simultaneous discharge of timing capacitors C2 and C3 in the pulse rate network 122. The pulse rate network 122 comprises means for establishing the time interval between or the rate of generation of output pulses from the pulse generating network 124. The pulse generating network 124 comprises means for generating pulses of predetermined width which are to be subsequently voltage amplified by the voltage converter 112, the width of the pulses remaining the same, and means for activating the strobe network for resetting the timing cycle of the oscillator 110.
The basic or normal pacer operating rate is set by the charging of capacitor C2 through resistor R2 until the voltage across the capacitor C2 reaches the threshold of logic gate G3 at its input terminal 18. Rate runaway protection, which is the concern of the present invention, is provided by the charging of capacitor C3 through resistor R3 until the voltage across capacitor C3 reaches the threshold of logic gate G2 at its input terminal 16; the gate G2 then activates and the output thereof, appearing on output terminal 23, is applied to the input terminal 17 of gate G3 to enable gate G3. Both input terminals 17 and 18 must have applied thereto the same high logic level signals in order to activate gate G3 and when this occurs, the signal on output terminal 24 of gate G3 activates the pulse generating network 124 comprising gates G4 and G5 via input terminal 19 of gate G4. An output of the pulse generating network 124, which is fed to the voltage converter 112, appears on the output terminal 25 of gate G4. The output pulse appearing on output terminal 25 (normally at ground level) is typically a 1ms wide positive pulse. Another output of the pulse generating network 124 appears simultaneously with the one appearing on terminal 25 at output terminal 26 of gate G5. This latter output is also typically a 1ms wide pulse, however, it is a negative pulse (normally at V DD level) and is applied via the feedback path K-L and diode D1 to activate the strobe network 120.
The strobe network 120 in turn, via the signal appearing on output terminal 3 of gate G1, turns on switches S1, S2 and S3, via input terminals 4, 7 and 12, respectively, for a sufficient length of time, nominally 3.5 ms, to essentially completely discharge capacitors C2 and C3. When the strobe network 120 deactivates, switches S1, S2 and S3 are turned off, thereby permitting capacitors C2 and C3 to begin charging again to start a new timing cycle, i.e., the oscillator 110 is reset.
Thus, the signal at input terminal 17 of gate G3 appears before that at input terminal 18. Since input terminals 17 and 18 must act together to activate gate G3 and subsequently the pulse generating network 124, the rate at which the pulse generating network 124 causes the delivery of an output pulse is thereby determined by the action of resistor R2 and capacitor C2.
From the foregoing it will be understood that the normal pacer operating rate, in the range of 60 to 100 beats per minute, is predetermined by the magnitude of capacitor C2 and resistor R2 which together establish the interval of time required for the voltage across capacitor C2 to reach the threshold of input terminal 18 of gate G3. Since time interval is the inverse of rate, a faster rate implies a shorter interval. In accordance with the invention, the magnitudes of capacitor C3 and resistor R3 are chosen such that the charging of capacitor C3 via resistor R3 is set for a faster rate (shorter interval), in the range of 110 to 150 beats per minute, nominally 120 beats per minute, than that set for capacitor C2 and resistor R2. The maximum safe pacer operating rate is considered by the medical profession to be 150 beats per minute with 180 beats per minute being considered possibly lethal. Therefore, while the pacer operating rate set for capacitor C3 and resistor R3 is above the normal pacer operating rate, it is still considered to be a safe pacer operating rate. It can thus be seen that resistor R2, capacitor C2 and resistor R3, capacitor C3 comprise pulse rate control means for pulse rate network 122.
At this point it should be explained that the packing density of circuit components in an implantable cardiac pacer is very high resulting in the possibility for a circuit malfunction to occur such that the rate of charging of capacitor C2 is increased and the interval of time required to reach the threshold of input terminal 18 is decreased. This would correspond to an increase in the normal pacer operating rate. In this circumstance, the signal at input terminal 18 can reach the threshold thereof before the signal at input terminal 17 appears, and thus, the rate of generation of output pulses by the pulse generating network 124 is limited to 120 beats per minute by the timing action of resistor R3 and capacitor C3.
A circuit malfunction that increases the charging rate of capacitor C2 can be caused by current leakage from an adjacent conductor run on a printed circuit board that would have the affect of reducing the value of resistor R2 which would tend to increase the charging rate of capacitor C2 and therefore increase the normal rate of oscillations of oscillator 110. A leakage path from a faulty gate, as for example gate G3 via input terminal 18, would cause terminal 18 to act as an output terminal feeding capacitor C2, or a leakage path from output terminals 5 and 8 of switches S1 and S2 would also cause them to act as output terminals feeding capacitor C2; the resulting affect would be for capacitor C2 to charge through a smaller value of resistance than resistor R2 causing an increase in the rate of oscillations of oscillator 110.
Alternatively, a malfunction in the timing circuit comprised of capacitor C3 and resistor R3 that would cause the signal to appear at input terminal 17 of gate G3 after a shorter interval of time than that corresponding to 120 beats per minute is of little consequence since the normal pacer operating rate of 72 beats per minute would still be set by the timing circuit comprised of resistor R2 and capacitor C2. Assuming independent events and a very low probability of failure for either of the timing circuits, the probability of both timing circuits failing at the same time is the product of the two probabilities. Thus, the likelihood of both timing circuits failing together is extremely remote.
Detailed Description of Oscillator 110
Considering the operation of oscillator 110 of FIG. 2 in greater detail, the sequence of circuit operations is shown in the timing diagrams illustrated in FIGS. 3a, 3b, 4a, 4b and 5. Referring now to FIGS. 3a and 3b, and starting first with a description of the pulse generating network 124 at time t o , we assume input terminals 17 (line 302) and 18 (line 300) of gate G3 have gone high with a resultant low output on terminal 24 (line 303) of gate G3. The latter low signal level is coupled via conductor A to input terminal 19 (line 303) of gate G4. In its normal or quiescent state, the input terminal 20 (line 304) of gate G4, which is tied to output terminal 26 (line 304) of gate G5 via conductor K, is high as is input terminal 19 of gate G4. Therefore, output terminal 25 (line 305) of gate G4 is normally low. When input terminal 19 of gate G4 goes low, output terminal 25 of gate G4 goes high. Prior to time t o , we assume the voltage across capacitor C4 is zero and since output terminal 25 of gate G4 is also zero, the voltage at input terminals 21 and 22 (line 306) of gate G5 is also zero or a logic zero. At time t o , when output terminal 25 of gate G4 goes high, input terminals 21 and 22 of gate G5 instantaneously go high because the voltage across capacitor C4 remains zero at the initial instant. After the natural delay through the gate (about 0.5 microseconds) output terminal 26 of gate G4 goes low as does input terminal 20 of gate G4. Now capacitor C4 begins to charge from power source V DD the output resistance of gate G4 and resistor R4. When output terminal 25 of gate G4 went high, the current in resistor R4 jumped instantaneously to a high value determined essentially by power source V DD and resistor R4. As capacitor C4 charges, the voltage drop across capacitor C4 increases exponentially; the current through resistor R4 and the voltage across it diminish correspondingly. When the diminishing voltage across resistor R4 reaches the negative threshold of input terminals 21 and 22 of gate G5, output terminal 26 of gate G5 switches from low to high at time t 3 . The time during which output terminal 26 of gate G5 remained low or the time during which output terminal 25 of gate G4 remained high is the width of the delivered output pulse fed to the voltage converter 112; this time is on the order of 1 millisecond. By circuit operation to be described below, the input terminal 19 of gate G4 remains low for a few brief microseconds before going high again at time t 2 . Yet it remained low long enough for the low signal at input terminal 20 of gate G4 to become established. At time t 3 , when input terminal 20 of gate G4 goes high, and since input terminal 19 of gate G4 is high, output terminal 25 of gate G4 returns to its normally low state.
Considering now the action of the strobe network 120, the input terminal 2 thereof is normally kept high by the operation of the refractory delay network 118. Input terminal 2 is caused to go low whenever an R-wave or an output pulse from the voltage converter 112 is sensed and fed back to the refractory delay network 118 via path F, amplifier 114 and monostable multivibrator 116. The sensing of either an R-wave or an output pulse from voltage converter 112 causes the refractory delay network 118 to drive input terminal 2 low resulting in a high signal on normally low output terminal 3 of gate G3. The significance of the action of the refractory delay network 118 on strobe network 120 will appear more fully hereinafter in the explanation of inhibited or demand pacer operation of the oscillator 110.
The negative going signal at time t o at output terminal 26 of gate G5 and terminal 20 of gate G4 is coupled via conductor L to diode D1. Prior to time t o , capacitor C1 had been charged fully to the voltage of the power source V DD via resistor R1. With output terminal 26 of gate G5 low, capacitor C1 now begins to discharge toward ground through diode D1 and the output resistance of gate G5. When the diminishing voltage on capacitor C1 crosses the negative threshold of input terminal 1 (line 307) of gate G1, output terminal 3 (line 308) of gate G1 which had been prior to t o normally low, goes high at time t 1 . This logic one level signal turns on switches S1, S2 and S3 via input terminals 4, 7, and 12 of switches S1, S2 and S3, respectively. Capacitor C2 (line 300) begins to discharge through the parallel combination of switches S1 and S2 and capacitor C3 through switch S3. Output terminal 3 of gate G1 has been designed to remain high long enough for capacitors C2 and C3 to become, for all practical purposes, completely discharged in time t 4 -t 1 , about 3.5 ms. This is insured by the recharging of capacitor C1 via resistor R1 after output terminal 26 of gate G5 and input terminal 20 of gate G4 return to logic one at time t 3 . Diode D1 blocks current flow into the capacitor C1 through the output resistance of gate G5. When capacitor C1 voltage reaches the positive threshold of input terminal 1 of gate G1, output terminal 3 of gate G1 returns to logic 0 thereby turning off switches S1, S2 and S3 at time t 4 .
As capacitor C3 discharges through switch S3, the increasing voltage across resistor R3 passes the positive threshold of input terminal 16 of gate G2 (line 301) resulting in a logic 0 at output terminal 23 of gate G2 and input terminal 17 of gate G3. As capacitor C2 discharges, the diminshing voltage across it passes the negative threshold of input terminal 18 of gate G3. Either of the foregoing events is sufficient to cause output terminal 24 of gate G3 to return to its normal logic 1 state at time t 2 .
Considering now the normal oscillator 110 timing operation, at time t 4 capacitor C2 begins to charge towards source voltage V DD via resistor R2 and capacitor C3 charges toward ground via resistor R3. When the diminishing voltage across resistor R3 reaches the negative threshold of input terminal 16 of gate G2, output terminal 23 of gate G2 and hence input terminal 17 of gate G3 switches from a normally low state to a logic 1 at time t 5 since input terminal 15 of gate G2 is tied permanently high. When the voltage across capacitor C2 reaches the positive threshold at input terminal 18 of gate G3, gate G3 now has two input terminals, at time t 6 , at logic 1 and therefore, output terminal 24 of gate G3 switches low. Thus a new timing cycle begins with time t 6 considered to be a new time t o . Note that input terminal 17 of gate G3 reaches a logic 1 level before input terminal 18 of G3 because the timing action of capacitor C3 and resistor R3 has been designed for a period of 500 ms (120 beats per minute) as compared to the timing action of capacitor C2 and resistor R2 which is normally designed for periods ranging from 1000 ms to 600 ms depending upon the normal pacer operating rate desired. Since the input terminal 17 of gate G3 waits for input terminal 18 of gate G3 to reach a logic 1, normal pacer operating rate is controlled by the timing action of capacitor C2 and resistor R2.
While the operation of the oscillator 110 will not be described with respect to the remainder of the timing diagrams shown in FIGS. 3a and 3b, the operating steps are shown in the timing diagram and may be readily understood with reference to the detailed explanation just given noting that time t 6 is to be considered a new time t o and that the time interval between time t 6 and time t 13 are equal.
Referring now to FIGS. 4a and 4b wherein except for line 402, lines 400-408 correspond to lines 300-308 of FIGS. 3a and 3b, a condition will now be described wherein a circuit malfunction has occurred resulting in a speed up of the timing action of capacitor C2 and resistor R2. Under such circumstances, input terminal 18 of gate G3 can reach a logic 1 level before that of input terminal 17 of gate G3 as is shown at time t 5a in FIG. 4a. However, after output terminal 23 of gate G2 becomes high, both inputs of gate G3 are now high and the same sequence of events as described above with reference to FIGS. 3a and 3b beginning a time t o takes place. Note that output terminal 23 of gate G2 remains high for only a short interval as contrasted with the situation in FIGS. 3a and 3b where it remained high for the length of time required for the timing action of capacitor C2 and resistor R2 to catch up. In this situation, the pacer timing rate is controlled by the timing action of capacitor C3 and resistor R3, the rate runaway protection network of the invention, and thus the pacer operating rate is limited to a safe 120 beats per minute.
The operation of the oscillator 110 just given essentially covered the situation of fixed rate operation. Referring now to the timing diagram shown in FIG. 5, which only illustrates the conditions of terminals 2 and 3 of gate G1 of the strobe network 120; line 500 also indicates the rate of occurrence of an R-wave in rate (not shape). During demand pacer operation, the strobe network 120 operates in a similar manner via input terminals 1 and 2 of gate G1 to cause capacitors C2 and C3 to discharge prior to their charging to voltages which would otherwise pass the thresholds at input terminal 18 of gate G3 and input terminal 16 of gate G2 thereby initiating a new rate timing cycle and preventing the generation of an output pulse from pulse generating network 124.
Stated another way, each time an R-wave is sensed and processed through the refractory delay network 118, input terminal 2 (line 500) of gate G1 goes low resulting in a high level signal on output terminal 3 (line 501) of gate G1 which in turn effects operation of switches S1, S2 and S3 which cause capacitors C2 and C3 to discharge before their respective voltages can reach the threshold level of the levels on input terminal 18 of gate G3 and input terminal 16 of gate G2. Thus, the high level signals at output terminal 23 of gate G2 and input terminal 17 of gate G3 would be terminated at time t 6a (prior to the time t 6 of FIGS. 3a and 3b). The waveforms on lines 303, 304, 305, 306 and 307, of FIG. 3 therefore never develop. Accordingly, in demand pacer operation, the rate of occurrence of the high level signal on terminal 3 (line 501) of gate G3 and its effects depends on the rate of occurrence of the sensed R-wave, causing, through the operation of the refractory delay network 118, input terminal 2 (line 500) of gate G1 to go low.
Examples of components illustrated in FIG. 2 are set forth in the table below:
__________________________________________________________________________Component Commercial Type__________________________________________________________________________Gates: G1, G2, G3, G4 and G5 Schmitt Trigger, or 1/4 RCA CD4011 Quad NAND gateSwitches: S1, S2, S3 Each, 1/4 RCA CD4066A Quad Bilateral SwitchDiode: D1 IN914Resistor: R1 About 3.0 meg. ohmsResistor: R2 About 600 K ohmsResistor: R3 About 6.0 meg. ohmsResistor: R4 About 420 K ohmsCapacitor: C1 and C4 1500 pico faradsCapacitor: C2 1.0 micro faradsCapacitor: C3 0.12 micro farads__________________________________________________________________________ | A cardiac pacer having an improved oscillator circuit therein which provides rate runaway protection in the event of circuit malfunction. The oscillator establishes the normal operating rate of the pacer and limits the pacer operating rate to a predetermined rate which, while above the normal pacer operating rate, is still considered to be a safe pacer operating rate. | 0 |
[0001] The present invention relates to an interactive multimedia apparatus usable in combination with a software suite of authoring programs installed in a computing means of a mobile data processing apparatus of the type having a display means and one or more input means.
[0002] The present invention is an improvement to the apparatus disclosed by the applicants in International Patent Publication No. WO2003/046913, the contents of which specification are incorporated herein by direct reference.
[0003] Electronic mixing software for PC and computer based products is known and there are packages available both commercially and as freeware over the internet. These packages allow users create tracks which contain loops, riffs, beats, one shots or the contents of a CD, track, microphone inputs, video files etc and to mix them together to produce their desired sound output compilation. The user places each selected loop, riff, one shot, video clip, CD output, microphone input etc. in a selected track position along the time axis ruler bar so that they are mixed at that time in the play cycle. The content, which can be WAV, MP3, WMA or any other digital media format being mixed, has been prepared at a recorded tempo and is of a fixed length of time. The desired mix will usually contain multiple tracks of differing beats, loops, riffs, one shots, voices, video etc.
[0004] Most digital mixing software packages allow the user to set up a series of controls and effects for each channel in advance of the mixing process occurring and will also allow some limited global control of the composite mix output. The control and effects are usually applied in advance of the mixing process occurring, but some limited control is allowed during the mixing cycle. Some of the individual track parameters, which are allowed to be altered during the mixing process, would include volume, mute, tempo and tone. Special effects are not normally allowed during the mixing process.
[0005] There are many digital software music-editing packages available on the market both commercially and as freeware over the internet. These packages allow the user to edit riffs, loops, beats, one shots, CD outputs and other media context by cut, paste, copy and other known techniques for editing digital content. The editing process requires the user to select a portion of the waveform and reposition or alter the characteristics and parameters of the waveform. The user can change the characteristics of the waveform, add effects, move it or reposition it with the same track, cut and paste it or copy it to a newly created track. The editing process is accomplished by using either a mouse or a keyboard or a combination of both. If the user wishes to use only a segment of a loop, beat, riff, one shot, video clip, microphone input etc they must first pre-edit it and then insert it in a track in its play position along the time axis ruler to be mixed at that predefined time in the mix cycle.
[0006] A problem with these known applications is that they are not able to be deployed to devices with limited processing power, and in particular, mobile data processing apparatuses, such as mobile telephones. Further problems arise in the use of mobile phones for such applications due to size restrictions on telephone displays and difficulties in presenting and navigating display information.
[0007] It is therefore an object of the present invention to provide an interactive multimedia apparatus for use in a mobile data processing environment which goes some way toward overcoming the above problems, and/or which may provide the public or industry with a useful alternative.
STATEMENTS OF INVENTION
[0008] According to the invention, there is provided an interactive multimedia apparatus usable in combination with a software suite of authoring programs installed in a computing means of a mobile data processing apparatus of the type having a display means and one or more input means characterised in that the apparatus comprises user control means operable to allow a user to transmit one or more of an audio file and a video file and a still image file and a text file, including a combination thereof, to a plurality of channels on the mobile data processing apparatus, and then to activate a selection of the channels to enable the files in the selected channels to be combined in a mixing cycle to generate a multimedia composition having one or more of audio content and video content and still image content and text content, and whereby the user control means is further operable to enable the user to set composition authoring parameters assigned to each channel, the parameters then being applied to the files in the channels by the authoring programs to generate the multimedia composition.
[0009] The present invention provides users with a collection of functions for processing multimedia files which together provide users with efficient tool for manipulating multimedia content into composition using a mobile device. The provision of the control means and channels for receiving media files provides users with a technical tool for the retrieval, selection and modification of the stored media files on the device. The arrangement of the channels and authoring tools in such a way as to be manipulated via the mobile device provides an arrangement enabling users to manage the technical tasks involved in composing a multimedia composition.
[0010] In another embodiment of the invention, the composition authoring parameters will modify, refine, adjust, vary and/or change performance characteristics of the files transmitted to the channels.
[0011] The ability for users to set composition authoring parameters will enable those users to be able to efficiently and directly manipulate characteristics of the input multimedia files to, for example, apply special effects, to the file content.
[0012] In a further embodiment of the invention, further comprising means for enabling the composition authoring parameters to be settable and adjustable during combining of the channels during the mixing cycle to form the multimedia composition.
[0013] This provides users with full control over the composition process by enabling users to be able specify, and where necessary, re-specify performance characteristics during the entire composition generation process.
[0014] In another embodiment of the invention, the mobile communications apparatus further comprises an accessible data store having one or more audio files, video files, still image files and/or text files stored thereon.
[0015] In a further embodiment of the invention, the multimedia composition is generated in real time.
[0016] The ability of the present invention to combine all the channels of media content to generate a composition in real time is particularly advantageous as it enables users to produce the multimedia compositions quickly and without any delay. With the limited processing capacity available to such devices this is a significant advance in the area of multimedia data processing.
[0017] In another embodiment of the invention, the user control means is further operable to enable users to specify the sequence of individual frames in a multimedia composition having video content.
[0018] This feature provides users with tool to efficiently specify changes to a composition having video content.
[0019] In a further embodiment of the invention, the interactive multimedia apparatus further comprises scanning means for searching the data store, and files stored on the mobile communications apparatus, for all files having predefined file formats.
[0020] In another embodiment of the invention, the files having different file formats are able to be combined into a single or multiple multimedia compositions.
[0021] In a further embodiment of the invention, the apparatus further comprises means for storing a record of the composition authoring parameters set for each composition.
[0022] In another embodiment of the invention, the apparatus further comprises means for presenting an indicator of each file which is suitable for use in a composition is presented for selection to the user on the display means of the mobile communications apparatus.
[0023] In another embodiment of the invention, the apparatus further comprises means for presenting an indicator of each channel is shown on the display means of the mobile communications apparatus.
[0024] In another embodiment of the invention, the file indicators are shown adjacent the channel indicators on the display means of the mobile communications apparatus.
[0025] In a further embodiment of the invention, an indicator of each composition authoring parameter is shown adjacent to the indicator of the channel to which it is assigned.
[0026] In another embodiment of the invention, means are provided for presenting an indicator of a file transmitted to a channel at a specific time is shown on the display means of the mobile communications apparatus
[0027] In a further embodiment of the invention, means are provided for presenting an indicator of the file format of a file transmitted to a channel at a specific time is shown on the display means of the mobile communications apparatus
[0028] In another embodiment of the invention, it is ascertainable from the indictors whether or not a composition authoring parameter has been set by a user and/or a file has been transmitted to a channel.
[0029] The indicators are arranged relative to one another in order to convey information to users concerning files and the progress of a composition. The ability for each file and the file format of a file to be represented visually on the mobile device enables a fast and efficient means for presenting files for selection by the user on the display means of the mobile device, which it will be appreciated, is of limited size.
[0030] In another embodiment of the invention, when a further file is transmitted to a channel already having a file transmitted thereto the further file replaces the file presently in the channel.
[0031] In a further embodiment of the invention, when a further file is transmitted to a channel already having a file transmitted thereto the further file is incorporated into the channel with the previously transmitted file.
[0032] In another embodiment of the invention, the apparatus further comprises means for enabling each composition generated to be transmitted as a multimedia message or e-mail, posted to a web-site, saved as a ring-tone, video-tune, caller identification and/or wallpaper and is also able to be saved for transmission to a further device.
[0033] Preferably, the mobile data processing apparatus is a mobile telephone.
[0034] It will be appreciated that the mobile data processing apparatus can alternatively be a portable digital assistant (PDA), MP 3 player, gaming device or other portable device.
[0035] Preferably, means are provided for enabling a multimedia composition generated to uniquely identify a telecommunications device which is calling the mobile data processing apparatus.
[0036] In another embodiment of the invention, the input means comprises one or more of a video camera and a video recorder and an audio microphone and a keyboard and a mouse and a touch screen and a 3D input device and a tactile sensor and a voice recognition device and digitising hardware.
[0037] In another embodiment of the invention, means are provided for a user to record their own voice and/or other sounds originating outside the mobile communications device and use those recordings to form part of a composition by transmitting to a channel.
[0038] In another embodiment of the invention, each composition has a start and a finish point which are shown on the display as spaced apart indicators, and means are provided for a user to edit sections of the composition with reference to the start and finish indicators.
[0039] In another embodiment of the invention, means are provided for users to create slideshows using multiple compositions and to assign text to be displayed on the display means to each slide in the slide show.
[0040] In another embodiment of the invention, the user control means is further operable to enable users to specify the sequence of slides in a slide show.
[0041] In another embodiment of the invention, means are provided for users to assign specific text and text effects to each channel for application to a composition.
[0042] In another embodiment of the invention, means are provided for a user to access further composition authoring parameters, including advanced editing features, for each channel once a file has been transmitted to a channel.
[0043] In another embodiment of the invention, the control means is further operable to enable users or mobile phone operators to set upper threshold size limits for compositions and/or individual files in a composition.
[0044] Preferably, means are provided for transmitting an alert is notified to a user via the mobile device when the upper threshold size limit is about to be reached or when it has been reached.
[0045] In another embodiment of the invention, means are provided for displaying the indicators for each file in a channel to users at a first resolution during the mixing cycle, and then on generation of the composition displaying the indicators for each file at a second resolution which differs from the first resolution.
[0046] In another embodiment of the invention, the first resolution is lower or higher than the second resolution.
[0047] In another embodiment of the invention, the apparatus further comprises means for enabling users to set the first and/or second resolutions.
[0048] In another embodiment of the invention, each file has a file extension which comprises tempo and beat map information for the file.
[0049] In another embodiment of the invention, the apparatus further comprises means for ensuring that the use of the present invention does not interfere with the normal operation of the mobile communications apparatus or prevent the execution of other applications on the mobile communications apparatus.
[0050] For the purposes of the following specification the term ‘authoring programs’ will be understood to include software programs being used for designing, creating, collecting, formatting, and/or encoding data for use in a multimedia composition.
[0051] For the purposes of the following specification the term ‘control means’ will be understood to include features of the mobile communications device enabling user interaction or input to initiate an action, display information, or set values and transfer data from or within the mobile communications device.
[0052] For the purposes of the following specification the term ‘performance characteristics’ will be understood to mean features affecting the way in which a file will be rendered, such as resolution, tempo or beat map.
[0053] For the purposes of the following specification the term ‘composition’ will be understood to include a multimedia mix of at least one file.
[0054] The present invention thus provides an interactive multimedia apparatus, usable in combination with a software suite of programs suitable for mobile communications apparatus installed in a computing means of a mobile communications apparatus with a display component and one or more input components. The apparatus includes control means which may be operated by users to effectively modify, refine, adjust, vary and/or change characteristics, parameters and special effects of individual audio or video tracks and/or characteristics and parameters and special effects of a composite audio mix during the mixing cycle in real time.
[0055] The mobile communications apparatus is a mobile telephone. Ideally the mobile telephone is a 2.5 G, 3 G or of higher specification and supports an operating system such as Windows Mobile 2003SE, however any suitable operating system known to a person skilled in the art can be used. Typically the application is implemented using C++ and Embedded Visual Tools 4, again any suitable implementing system known to a person skilled in the art can be used. Conveniently the mobile telephone of the invention has a input means forming a user interface driven by a touch screen and/or front panel keys on the phone. In such an embodiment, the left, right, up down, enter which may correspond to numerical keys 4\6\2\8\enter respectively).
[0056] The authoring programs and other executable files associated with the present invention are provided by a series of dynamic link libraries. Conveniently the files are packaged up into a cabinet file (.cab file) which may be executed on a mobile telephone to thereby install the mobile telephone. Methods such ActiveSync would be suitable to achieve this.
[0057] The present invention also allows users to record any dynamically applied parameters, such as any special effects initiated by the user control means, which have been applied during the mixing cycle and/or generation of the multimedia composition. The user is also provided with a visual representation in the form of a pictograms, icons or other representation or indicator of each track or file in the mix.
[0058] The position in time that the user initiated or set various composition authoring parameters during in the mix cycle is also shown, with highlighted blocks or indicators showing which of the various performance characteristics of the files which have been changed, as well as where additions, deletions or modifications, control changes, parameter changes and/or special effects have been applied.
[0059] User can record their own voice and/or other external sounds and use those recordings to form part of a composition.
DETAILED DESCRIPTION OF THE INVENTION
[0060] The invention will hereinafter be more particularly described with reference to the accompanying drawings which show, by way of example only, one embodiment of the system of the invention. In the drawings:
[0061] FIG. 1 shows the main menu screen with Music Mix icon selected;
[0062] FIG. 2 shows the file explorer and channel assignment screen indicating sample directories and with ‘my music’ directory selected;
[0063] FIG. 3 shows the file explorer and channel assignment screen with the ‘My Music’ directory opened and sample files contained therein;
[0064] FIG. 4 shows the file explorer and channel assignment screen with the ‘Assign to Channel’ menu opened;
[0065] FIG. 5 shows the template view screen with a sample template file selected;
[0066] FIG. 6 shows the Music Mix screen with channel 1 selected;
[0067] FIG. 7 shows the Preview Mix & Save and Send screen with ‘Set as ring tone’ selected;
[0068] FIG. 8 shows the Windows Mobile Save As screen with sample information indicated;
[0069] FIG. 9 shows the Voice Record screen with sample files indicated;
[0070] FIG. 10 shows the Help screen;
[0071] FIG. 11 is schematic illustration of the components of the StikAx TM Mobile Application software;
[0072] FIG. 12 is a block diagram illustrating the audio mixing engine;
[0073] FIG. 13 is a table showing the registry entries for the user interface layer;
[0074] FIG. 14 shows a channel assignment screen where the user will be able to find all supported media files on the device and assign media to each of the channels;
[0075] FIG. 15 shows an Advanced Audio screen where the user can edit sections of the audio;
[0076] FIG. 16 shows an Advanced Video screen where the user can edit sections of the video;
[0077] FIG. 17 shows an Advanced Image Screen where the user can create slideshows using multiple image files and assign transition and text effects;
[0078] FIG. 18 shows an Text Effects Screen where the user can assign start and end credits to their mix as well as assigning text and text effects to individual channels;
[0079] FIG. 19 shows an Mixer Screen where the user can create live mixes using any combination of audio, video or images;
[0080] FIG. 20 shows an ‘Save’ screen where the user can save their mix to the format and location of their choice;
[0081] FIG. 21 is a block diagram of a system incorporating the interactive multimedia apparatus according to the present invention.
[0082] Referring to the drawings, and initially to FIG. 21 thereof, there is shown an interactive multimedia apparatus, indicated generally by the reference numeral 1 usable in combination with a software suite of authoring programs 2 installed in a computing means of a mobile communications apparatus, which in the instance shown is a mobile telephone 3 having a display means 4 and one or more input means formed as an alphanumeric keypad 5 . It will be appreciated however that, depending on the specific mobile communications device being used the input means may also comprise one or more of a video camera and a video recorder and an audio microphone and a keyboard and a mouse and a touch screen and a 3D input device and a tactile sensor and a voice recognition device and digitising hardware.
[0083] With reference now to FIGS. 1 to 6 , the apparatus 1 comprises user control means operable to allow a user to transmit files, indicated generally by the reference numeral 10 , which files may be an audio file, a video file, a still image file and a text file, including a combination thereof, to a plurality of channels, indicated generally by the reference numeral 11 on the mobile telephone 1 . In the instance shown, four channels 11 a - 11 d are provided although it will be appreciated that any number of channels can be provided.
[0084] It will be appreciated that the mobile telephone 3 further comprises an accessible data store 6 (see FIG. 21 ) having one or more of the files 10 , namely audio files, video files, still image files and/or text files stored thereon. The mobile telephone 3 also comprises scanning means for searching the data store 6 , and files 10 stored on the mobile telephone, for all files having predefined file formats. Such predetermined formats will generally include all of those file formats which are able to supported and included into a multimedia composition as it will be understood that files 10 having different file formats are able to be combined into a single or multiple multimedia compositions. An indicator 12 for each file 10 which is suitable for use in a composition is presented for selection to the user on the display means 4 of the mobile telephone 3 . An indicator 13 for each individual channel 11 a - 11 d is also shown on the display means 3 , as is an indicator of each file 10 transmitted to a channel at a specific time. In the instance shown, the file indicators 12 are shown adjacent the channel indicators 13 .
[0085] During the mixing cycle the indicators 12 for each file in a channel are displayed to users at a first resolution, and then on generation of the composition the indicators 12 for each file are displayed at a second resolution which differs from the first resolution. Generally, the first resolution is lower than the second resolution and users are able to set the first and/or second resolutions.
[0086] The user control means is operable to activate a selection of the individual channels 11 a - 11 d to enable the files 10 in the selected channels to be combined in a mixing cycle to generate a multimedia composition having one or more of audio content and video content and still image content and text content. The multimedia composition is generated in real time. The control means also enables users to transmit a further file 10 to a channel 11 already having a file transmitted thereto and users can specify whether the further file is to replace the file presently in the channel or whether it is to be incorporated into the channel with the previously transmitted file.
[0087] The user control means is further operable to enable the user to set composition authoring parameters, indicated generally by the reference numeral 14 , which are assigned to each channel 11 a - 11 d . Such composition authoring parameters 14 may relate to volume settings for each channel 11 a - 11 d or the application of various templates to the file content to, for example, modify the speed or tempo of an audio file, apply special effects to the file. It will therefore be understood that the composition authoring parameters will modify, refine, adjust, vary and/or change performance characteristics of the files 10 transmitted to the channels 11 . The composition authoring parameters 14 once set are then applied to the files 10 in the channels 11 a - 11 d by the authoring programs 2 in the mobile telephone 3 to generate the multimedia composition. The composition authoring parameters 14 are also settable and adjustable during combining of the channels to form the multimedia composition. In this way users may adjust previous settings for the composition authoring parameters 14 during the mixing cycle.
[0088] The control means is further operable to enable users or mobile phone operators to set upper threshold size limits for compositions and/or individual files in a composition. An alert is notified to a user via the mobile device when the upper threshold size limit is about to be reached or when it has been reached.
[0089] Also provided are indicators 15 for each settable composition authoring parameter 14 . In the instance shown the indicators 15 a - 15 d are shown adjacent to the channel indicators 11 a - 11 d to which it is assigned. It is ascertainable from the indictors 15 a - 15 d whether or not a composition authoring parameter 14 has been set by a user and/or and the specific files 10 a - 10 d which have been transmitted a channel 11 a - 11 d . For each composition generated a record of the composition authoring parameters 14 set is also stored for future access by users. Users may also specify the sequence of individual frames in a generated multimedia composition.
[0090] Each composition generated is able to be transmitted via a telecommunications network as a multimedia message or e-mail, posted to a web-site, saved as a ring-tone, video-tune, caller identification and/or wallpaper and is also able to be saved for transmission to a further device.
[0091] A composition may also be used to uniquely identify a telecommunications device which is calling the mobile telephone.
[0092] Referring now to FIG. 14 , a specific embodiment of the present invention will be described. In this embodiment, users are able to view thumbnail images of all supported media files on the display and assign files to each of the six channels 40 a - 40 f.
[0093] With reference to FIG. 14.1 , shown are file thumbnail views by file type (audio, video, image and project). These icons or indicators may be selecting using drop-down menu 41 or deselected as required. The bottom of the screen provides indicators 42 for the selected filter types. The user can therefore filter the thumbnail views by location by selecting the ‘filter by location’ option in the drop down menu (not shown in this figure). Once the user enters the desired location the media browser will only display supported files stored in that location.
[0094] Referring FIG. 14.2 , the user can preview an audio file by highlighting an audio file in the media browser and selecting the “preview” option on the soft key options. The preview playback options are: play, pause and stop. When the user selects to preview an audio file a “file explorer” style media pop-up player control will be displayed. No further activity on the application is possible during audio file preview play. The user can also create an ‘audio note’ file by selecting the microphone option on the Menu drop-down menu (not referenced in this figure). The user can also transmit a media file to a channel 40 a - 40 f by either highlighting a file and then moving the cursor to the desired channel number then pressing the ‘assign’ icon, or alternatively by pressing the ‘assign’ option in the drop-down menu 43 .
[0095] An audio, video still image and/or text file can be assigned to any channel in any combination.
[0096] The user can remove the file from a channel by pressing the ‘clear’ option in the drop-down menu 43 . If more than one transmission is made to a channel the latest assignment will override the existing assignment with the exception that the user may add an image file to a channel where an image file is already assigned.
[0097] Referring now to FIG. 14.3 , the status of each channel is shown by background and foreground colour coding—the channel will remain grey until a file is transmitted to a channel and when it is it will change to a highlighted colour. The current position in the list of available media files will be shown with background colour coding—the currently selected file will have a blue background.
[0098] The type of file assigned to a channel shall be shown with a pictogram button showing an icon of the file type (audio, video, image and text), which becomes highlighted and active once the file transmission is made.
[0099] The ‘Progress to Mixer/Start Mix’ option in the drop-down menu will remain disabled until the user transmits a file to a channel 40 a - 40 f. The user can progress to the mixer screen by selecting the ‘Start Mix’ button 44 at the bottom right of the screen, which becomes active once any channel 40 a - 40 f has received a file.
[0100] The user can also access further composition authoring parameters, including advanced editing features for each channel 40 a - 40 f (dependant on file type) by selecting the ‘Advanced’ option in the drop-down menu once a file has been transmitted to a channel.
[0101] FIGS. 15 and 16 show further composition authoring parameters available for use by users and include an option enabling users to define new start points and end points for files being mixed in each channel. The user can preview the file, apply start and end cut points and preview the resultant edited file. The user selects the new start and end points of the file by selecting the ‘Start Cut’ 50 or ‘End Cut’ 51 either during playback or when paused. The new start/end points will be shown on both the progress and preview screen at all times. The default playback value for video and image files in a mix is set to loop once, whilst the default audio files is loop continuously. These default values can be toggled by the user with the “loop” button 52 . The application will highlight the selected start and end points of the file using colour effects and markers.
[0102] FIG. 17 illustrates a tool enabling a user to create a slideshow from a selection of images previously selected when the files were transmitted to a channel. With reference to FIG. 17.1 , the user can change the order in which the images will appear in the slideshow using the Playlist ‘Move Up’ button 53 and ‘Move Down’ button 54 on the drop down-menu list. A user can also remove an image from a play-list using the ‘Remove’ button 55 on the Menu drop-down menu list. The user can change a transition effect between the images in the slideshow using the Effect button 56 in the drop-down menu list. The user can thus select the transition effect direction in the slideshow and the time that each image is displayed in the slideshow by using the scroll list boxes and highlighting the desired direction (if applicable) and time. The user can also preview and control playback of the slideshow.
[0103] For applying text effects a pop-up window will be shown displaying a text entry dialogue box 57 , font selection 59 , font colour selection 58 , where this effect is to be applied in a channel and a channel number selection tick box.
[0104] FIG. 18 shows the provision of utility enabling users to define text effects for start and end credits for all channels. The user selects to either add start or end titles by selecting one of the two text effect buttons. The user can define Start Credit text (which becomes enabled once the mix is started and will be displayed prior to any other channel), change the font, font size, font colour, transition effect, direction and enter the text from this screen. The playback of the Start Credit text effect will occur at the start of the mix The user can define End Credit text (which becomes enabled once the mix is stopped), change the font, font size, font colour, transition effect, direction and enter the text from this screen. The user can preview and control playback of the text effect by selecting the following buttons: Play/Pause.
[0105] It will be understood that compositions can contain any combination of audio, video, text or images and is not restricted or limited in the number of mixing channels that can be accommodated. Channels can be enabled/disabled without a mix running. The audio channels can be simultaneously mixed.
[0106] The user can navigate the channels using either the navigation pad or the corresponding key numbers on the keypad. Once in control of a channel, the volume of each channel can be independently controlled using the volume slider controls 60 which can be moved up and down using the navigation pad. The volume of each channel can be changed when the channel is enabled or disabled. The master volume for the mix can be changed using the master volume slider control 61 . Once in control of the master volume channel, the volume can be brought up, down or muted using the navigation pad. The master volume can be adjusted whilst a mix is running. An effect can be applied to a channel when the channel is enabled or disabled. An effect is stopped being applied to a channel by selecting and activating the effect enable/disable button at any point during a live mix. When a channel with audio media is enabled it will start playback from the start of the file and loop continuously (default setting that can be changed in the Advanced Audio screen). When a channel with video media is enabled it will start playback from the point at which the file was last enabled and play once through only (default setting that can be changed in the Advanced Audio screen). A mix is finished when the ‘Stop Record’ button 62 is selected and activated ( 19 . 2 (A)).
[0107] The save screen is accessible once a composition is created. Changing the media selection erases any current mix.
[0108] From selection list 63 as users may wish to send their mix as a MMS (Multimedia Messaging Service) or email from their mobile telephone, or post the composition to a web-site, save it as a ring-tone, video-tune, caller identification and/or wallpaper or save it for transmission to a further device they may want to set the complete file size of the mix to, for example, the optimum settings for MMS and email formats. With reference to FIG. 19.3 , the size of the mix can be pre-determined by a Wizard function; once that size has been reached, the application will automatically stop the current mix at that point.
[0109] FIG. 20 shows the ‘Save’ screen and with this screen the user send their mix as a MMS (Multimedia Messaging Service) or email from their mobile telephone, or post the composition to a web-site, save it as a ring-tone, video-tune, caller identification and/or wallpaper or save it for transmission to a further device. The user can control playback of the last saved mix file by selecting and activating the buttons: Play/Pause/Stop button 64 . The user can save a composition by selecting and activating the “save mix as” button 67 . The user can then enter the desired filename, location and file type. The user can also save their mix as a project by selecting and activating the “save project” button 65 , which saves the time-stamped file of the mix and the media clips used to a default location.
[0110] The user can also ‘Render the Mix to the Device’ and decide on the type of file they wish to create, i.e. unlimited mix, ring-tone, video-tune, wallpaper or caller ID.
[0111] A further embodiment of the present invention shall now be described, again with reference to FIGS. 1 to 13 , in which the present invention has been deployed on a mobile telephone or other mobile communications device. In this embodiment reference will be made to the use of audio files having the .WAV file format, however it is to be understood that present invention can be implemented for use with a wide variety of file types, including audio files, video files, still image files and a text files and is this suitable for use with formats including JPEG, TIFF, MPEG, AVI and so forth.
[0112] FIG. 1 shows the execution of the present invention on the display means of the mobile telephone, and in particular shows the what is displayed when the interactive multimedia apparatus is first started. The display means 3 shows two selectable indicators or icons, namely a ‘Music Mix’ icon 20 , which if selected brings the user to a file explorer and assignment screen, and a ‘Help’ icon 21 which can be selected to start up a ‘Windows Mobile Help’ application (see also FIG. 10 ). It is possible to include further icons to enable users to select, for example, an image and video mix if so desired. The icons are selectable by for example, double tapping the icon using a touch screen, using the front panel keys on the mobile telephone (left, right, up and down which may correspond to numerical keys 4, 6, 2 and 8 respectively) to select the icon and pressing the enter key (also on the front panel) or a single tap on the icon followed by pressing the front panel enter button.
[0113] On starting the application by selecting the ‘Music Mix’ icon, audio file scanning of all files accessible by the mobile telephone commences. Thus if a hard disc or memory card, such as, for example an SD memory card, has been inserted into mobile telephone it to is also scanned.
[0114] As shown in FIGS. 2 and 3 , a list of all waveform audio files (*.WAV) located during the search is generated and presented to users in a folder entitled ‘My Music’. A template folder within the operating system of the mobile telephone is also scanned for template files. Each template consists of four .WAV channels beat-matched ready for mixing. During the scanning period the message ‘Scanning, please wait’ is displayed on the display means and whilst this message is being displayed the music mix icon is disabled and may be ‘greyed’ out so as to indicate to users that it is presently unavailable for selection.
[0115] It will be appreciated that the present invention provides a ‘Windows Explorer’ like interface and shows a list of folders indicating the location of the files found during file scanning. This includes the ‘My Music’ folder icon 22 and the ‘templates’ folder icon 23 . The right side of the screen shows the four beat-matched .WAV channels 11 a - 11 d and the currently assigned files 10 a - 10 d for each of the beat-matched .WAV channel.
[0116] Navigation between the display icons is controlled using the left and right arrow keys of the alphanumeric keypad of the mobile telephone. Each feature on the display is highlighted in turn by manipulation of the left and right arrow keys. If an icon is highlighted and the enter key is then selected pressed then the icon is selected.
[0117] The icons on the left hand side of the display may be navigated and selected by, for example, double tapping on a folder to change the explorer view to list the files or directories in the current folder, and to list the files name and extension, as well as by using the up and down arrow keys to move between icons and then selecting or pressing the enter key to expand or collapse a drop down directory.
[0118] With reference now to FIG. 4 , the transmission of a file to a channel is shown and involves either dragging and then dropping a selected file onto a channel icon or selecting a desired file by reference to a file indicator and then using up/down arrow keys and then pressing enter to display the channels, in this case four channels, to which the files may be transmitted. The user selects the desired channel or alternatively can cancel the operation.
[0119] When a file is transmitted to a channel it starts playing automatically. Stop icons or buttons are displayed next to each channel to allow the user to stop a channel at any time. If a second or subsequent channel is played while a first channel is actually playing then the first channel is automatically stopped prior to the second or subsequent channel being played.
[0120] With reference to FIG. 5 , template selection is achieved using either dragging and dropping of one or more template, wherein dropping a template onto any channel loads the selected template thereby assigning the component files to the channels one to four automatically. Alternatively, the arrow keys on alphanumeric keypad of the mobile telephone may be used to select one or more desired templates and subsequently pressing the enter key to load the selected template(s) to the required channels.
[0121] A play button is additionally displayed for each channel to allow playing of each template channel component.
[0122] FIG. 6 shows a volume control for each channel, a master volume control and five icons comprising a stop button which stops the mix session, a save button which moves the user to the save and send screen, a back button which moves to the channel assignment screen, a help button which launches the mobile help application (see FIG. 10 ) and a record button which starts the recording session.
[0123] A preview play icon is provided which if selected plays the file in each channel continuously in a loop until the user clicks the stop icon.
[0124] Also shown are volume levels icons, support for playback of four channels in real time as opposed to static intervention after the composition has been generated. The user is also able to hear the resulting mix of the four channels in real time. Furthermore the user can toggle between each channel during a mixing session and use the volume slider on each channel during a mix, as well as setting various composition authoring parameters.
[0125] With reference to FIG. 7 , the display shown indicates various options available to user with regard to the multimedia composition. For example, users may wish to listen to the mix and then use the resultant composition, which it will be appreciated is also stored as a file. A preview control panel is provided which allows the user to preview a composition prior to saving, or indeed assigning as a file for a new composition. The preview control panel includes a play button to start playing the mix and a stop button to stop playing the mix. The preview control panel also has a slider bar 16 to indicate the position of the track in time during play of the mix. This indicator in the slider bar moves along while the mix is playing to indicate the current position in the mix track.
[0126] Located directly below the preview control panel is a menu 17 providing various user options including saving the composition to a file. This option, if selected, will bring the user to the Windows Mobile standard ‘save file as’ screen (see FIG. 8 ). Also included are options to set the composition as a ring tone, set composition as a caller ID, send the composition as an email, send the composition as a text message (MMS), and delete the composition.
[0127] Located at the bottom of the screen are back button which provides a cancel option an Options button and a help button which launches the Windows ‘TM Mobile’ help application loaded with html for this application (see FIG. 10 ).
[0128] Referring now to FIGS. 8 , 9 , and 10 , the format of the standard Windows TM Mobile ‘Save As’ screen 18 , standard Windows ‘TM mobile’ voice recorder application and standard Windows ‘Mobile help’ application loaded with html help pages for this application are shown therein. The display of these elements can be supported in landscape or portrait mode.
[0129] In this present instance, the composition created from the four channels is saved in .WAV format. The file size is limited to 95% of the available space left in the mobile teleohones accessible data store. The mix recording session is stopped if the file gets too large and the user is notified by an alert in a ‘pop-up’ screen. Furthermore the user is notified if a record session is started and there is not enough space left to continue.
[0130] Referring now specifically to FIG. 11 , the present invention has a system structure comprising a user interface layer 70 , an audio mixing engine layer 71 and a phone audio driver layer 72 (entitled ‘WAV1’). The audio mixing engine layer is implemented as a flat dynamic link library (DLL) and comprising a number of application programming interfaces (APIs) which are able to be deployed to the mobile telephone. There shall also be a library file for the user interface executables to link to and a header file for function prototypes.
[0131] Referring now to FIG. 12 , the engine supports four players 33 a - 33 d in which one player is assigned to each channel. This allows the control means of the present invention to play each file selected for a specified channel. The actual combining or mixing of the four channels is performed using the auxiliary audio driver 34 . The output from this driver is relayed to the phone audio driver 35 to play the composition in real time. The output from the auxiliary driver 34 also writes the mixed samples to a temporary file located in the data store accessible by the mobile telephone.
[0132] It is preferable for there to be sufficient CPU resources to render and play the composition in real time. In the event that there is insufficient CPU resources a two stage process implemented. The phone audio driver 35 is used to play and mix the file content in real time and to log the mixing volume changes, as well as channel toggles then renders the mix to a file as a separate stage using the auxiliary audio driver 34 . Each player 33 a - 33 d is capable of playing the content of a specified file. There is an API to assign a file to one of the four channels. Each player then has an API to start a channel playing and to stop it for the purpose of previewing a selected file. Each player shall use the waveform audio API set to write audio samples to the phone audio driver 35 when playing a single channel and the auxiliary audio driver 34 when in mixing mode. There are also APIs to start and stop the mixing process.
[0133] The auxiliary audio driver 34 is responsible for performing the audio mixing. It will be appreciated that in the event that different file types, such as video, image and/or text are being mixed then these components may be adjusted as required to take account of the different file types. The auxiliary audio driver 34 is based on a Unified Audio Model (UAM) driver that has support for multiple streams and built in mixing. The output from the players 33 a - 33 d is input to this auxiliary audio driver 34 . The resultant mixed stream is available for live play by transmitting it to the phone audio driver 35 using the waveform audio API set and is available for writing to a temporary file to store the mix as a file. Ideally the mixed stream is 44.1 kHz audio. The driver is called auxwav.dll and is loaded when the mixer application is run for the first time using the “RegisterDevice” API.
[0134] The following is an example of the registry keys which are required for the drivers.
[HKEY_LOCAL_MACHINE\\Drivers\\Drivers\\Custom\\auxwav “Prefix”=“WAV” “Dll”=“auxwav.dll”
[0138] These keys are written by the installation program. A reboot is required after installation.
[0139] The data store accessible to the mobile telephone also uses a file system which is responsible for saving the raw samples output from the auxiliary wave driver 34 . This may be a temporary file and would optimally be located in “\My Music\tempmix.WAV” and is a stereo 16 bit, sampling frequency 44.1 kHz. All APIs return a HRESULT. S_OK output for success and E_INVALIDARG for illegal input parameters.
[0140] Some of the APIs available to the User Interface Layer are listed below;
(1) Init HRESULT Init( )
[0143] This API performs initialisation for the control means and must It needs to be called each time the multimedia application is launched.
(2) Channel Player Controls APIs
(a) SelectWavFile HRESULT SelectWavFile(BYTE byChannel, LPCTSTR pzFilename)
[0147] This API assigns a wav audio file to a channel.
[0148] Inputs:
byChannel, Channel 1 to 4 pzFilename, full path to specified audio file.
(b) Play HRESULT Play(BYTE byChannel)
[0153] Start playing the specified channel. If another channel is playing then it shall be stopped.
(c) Stop HRESULT Stop(BYTE byChannel)
[0156] Stop playing the specified channel.
(3) Mixing APIs
(a) StartMix HRESULT StartMix( )
[0160] This starts the mixing session. All four channels are played live at the same time. The mixed file is recorded to the temporary file “\My Music\tempmix.WAV”. If there is not enough space to continue then ERROR_DISK_FULL is returned. If space runs out during a mix session a windows message is broadcast as described later.
(b) StopMix HRESULT StopMix( )
[0163] This stops the mixing session. The audio play back is stopped. The temporary mix file is closed.
(c) SetMixVolume HRESULT SetMixVolume(BYTE byChannel, BYTE byVolume)
[0166] This sets the volume on the mixer screen.
[0167] Inputs:
byChannel, the channel to change the volume (1-4).
[0169] To change the master volume, specify the channel as 0.
byVolume, the volume level to set (0-100).
[0171] This allows the user interface to obtain the current volume settings.
(d) GetMixVolume HRESULT GetMixVolume(BYTE byChannel, BYTE *pbyVolume)
[0174] Inputs:
byChannel, Channel 1-4 or 0 for master volume
[0176] Outputs:
pbyVolume, the returned volume level (0-100)
(e) PlayMix HRESULT PlayMix( )
[0180] Plays the mix as stored in the temporary mix file.
(f) StopPlayingMix HRESULT StopPlayingMix( )
[0183] This stops the mix playing.
[0184] Returns the current play position as expressed as a value 0 to 100.
(g) GetMixPlayPosition HRESULT GetMixPlayPosition(WORD *pwPosition) (h) GetVersions
[0188] The following API is used to retrieve the versions of the auxwav driver dll and the StikAx_Mixer dll.
HRESULT GetVersions(STIKAXDLL_VERSION* pVersion) Where STIKAXDLL_VERSION is defined as a structure
Int iAuxwavMajor; Int iAuxwavMinor; Int iStikAxMajor; Int iStikAxMinor;
[0196] When there is insufficient memory space left on the filing system during saving of a mixed file a message stating DISK FULL is displayed.
[0197] The CAB file referred to above in respect of FIG. 11 is produced to install the software on the phone using, for example, ActiveSync. This CAB file shall perform tasks including copying the executables and dynamic link libraries to the device, installing program icon in program menu, making the necessary registry changes, registering aux wav driver and/or re-starting the device.
The Registry
[0198] The user interface layer shown in FIG. 11 uses registry entries to store information. These entries can be found under HKEY_LOCAL_MACHINE\Software\Intrinsyc in the device registry, and are described in the table shown in FIG. 13 .
[0199] Template files contain track file names and directory information. This information is stored in the following format Directory,filename.
[0200] For example:
\My Documents\My Music\, Test4.WAV; \My Documents\My Music\, Test1.WAV; \My Documents\My Music\, Test2.WAV; or \My Documents\My Music\, Test3.WAV.
[0205] Each audio mixing engine API is called using the following methods.
(a) Init Calls the Init( ) API method. Initialises the mixing engine; (b) SendWavFileToEng Calls the SelectWavFile(byChannel, pzFilename) method; (c) PlayChannel Call the API method Play(byChannel); (d) StopChannel Calls the API method Stop(byChannel); (e) StartAudioMix Calls the API method StartMix( ); (f) Stop AudioMix Calls the API method StopMix( ); (g) SetAudioMixVolume Calls the API methos SetMixVolume(byChannel, byVolume); (h) GetAudioMixVolume Calls the API mmethod GetMixVolume(byChannel, byVolume); (i) PlayAudioMix Calls the API method PlayMix( ); (j) StopPlayingAudioMix Calls the API method StopPlayingmix( ); (k) DeleteAudioMix Calls the API method DeleteMix( ); and (l) GetAudioPlayMixPosition Calls the API method GetMixPlayPosition(*pwPosition).
[0230] The method arguments byChannel, byVolume, pzFilename and pwPosition are declared as BYTE, BYTE, LPCTSTR and WORD* respectively.
[0231] It will of course be understood that the invention is not limited to the specific details described herein, which are given by way of example only, and that various modifications and alterations are possible within the scope of the invention. | An interactive multimedia apparatus ( 1 ) usable in combination with a software suite of authoring programs ( 2 ) installed in a computing means of a mobile data processing apparatus ( 3 ) of the type having a display means ( 4 ) and one or more input means ( 4 ) is disclosed. The interactive multimedia apparatus ( 1 ) provides a bundle of tools which together enable a multimedia composition to be generated in real time on the mobile data processing apparatus ( 3 ). The present invention utilizes individual channels ( 11, 40 ) to ensure users can interact directly with individual files ( 10 ) and set various composition authoring parameters ( 14 ) both before and during a mixing cycle to dynamically create a multimedia composition. | 6 |
TECHNICAL FIELD
[0001] This invention relates to a culvert end. In particular, the invention relates to a culvert end that decreases the severity of motor vehicle accidents wherein the culvert has an end that is deformable under impact to create a transitioning surface to reduce the likelihood of the vehicle arresting, catching or snagging itself in the entrance to the culvert.
BACKGROUND
[0002] A safe road system is one where drivers rarely leave the road; but when they do, the vehicle and roadside are both designed to help protect vehicle occupants from death or serious harm, or at least minimize the harm. There are limits to the kinetic energy exchange that humans can tolerate, during rapid deceleration associated with a crash, before serious injury or death occurs.
[0003] A key contribution to improved road safety outcomes requires that road infrastructure and hardware be designed to take into account these errors and vulnerabilities. In the event of a crash it is desirable that the crash energy is managed to tolerable levels through either cushioning the impact or redirecting the vehicle around or over the obstruction.
[0004] In the United States for 2006, there were 17,241 single vehicle run off the road (SVROR) fatalities, representing 48 percent of the total of 42,769 fatalities (1). A review of the SVROR data shows that over 90 percent of the fatalities were a consequence of inadequate roadside treatments (1). In 73 percent of the SVROR crashes, a collision with a fixed object was the first harmful event (1). The first harmful event for a further 19 percent was an overturned vehicle (1). The data from France for 2003, shows that a similar proportion of crash deaths (21 percent) were due to collisions with ditches or embankments (2).
[0005] A review of New Zealand crash data, between 2003 and 2008 inclusive, indicates that over 90 percent of all crashes involved objects being struck on the roadside (3). Sixty percent of all objects struck were ditches (3). The higher NZ statistics for ditch impacts may be attributable to the generally narrower roads, and more abrupt, deeper ditch cross sections.
[0006] Ideally, if a vehicle inadvertently crosses the shoulder the driver should be able to recover safely. If the driver travels onto the roadside, the probability of a crash occurring depends upon the roadside features, such as the presence and location of fixed objects, shoulder drop-off, side slopes, ditches, and trees. If the roadside is fairly flat without objects and the soil can support the vehicle weight, then the probability of a serious crash is minimal (and indeed, in many cases the driver can fully recover and there will be no SVROR crash).
[0007] Addressing SVROR crashes presents significant challenges because of the extent of road networks, variations in traffic volumes and speed, and the random occurrence of these types of crashes. Identifying and implementing cost-effective countermeasures on road networks will continue to be an ongoing challenge.
[0008] Solutions to addressing SVROR crashes are generally directed at reducing the number and density of roadside features, their proximity to the traveled way, and relative obstructiveness will contribute to both a reduction in SVROR crashes and their severity. Crash severity can be reduced through changes in the design of roadside features, for example, making roadside hardware more forgiving, or modifying side slopes to prevent rollovers.
[0009] Roadside culverts present a significant danger in the event of an accident. Roads, particularly in the countryside are often bordered by a ditch. Such ditches are to designed to help drain water away from the roads and other structures, preventing water damage to the road foundation as well as preventing surface flooding. In order to maintain the integrity of the drain, intersecting roads or entrance ways and the like, have a culvert, or tube, running under and across it to allow water to continue flowing along the drain. Culverts such as this generally run parallel to the main road.
[0010] In a loss of control event where the vehicle leaves the road and enters the ditch there is a high likelihood of a head on crash into an intersecting embankment and culvert end. In such situations, the vehicles kinetic energy will generally be maintained in the direction of travel. A culvert presents a significant danger as it has been established the end will often “catch” or snag a part of the vehicle, generally the bumper, wheel or part of the under carriage, causing the vehicle to arrest or roll and increasing the chances of occupant injury or death (5).
[0011] To make such culverts safer the drainage culvert ends have been made traversable; achieved through eliminating snagging hazards. Such safety ends are especially important at road locations with a high possibility of head on crashes with parallel drainage structures that are under intersecting driveways and roads.
[0012] An intersecting road embankment can also be made safer by grading the side slope to improve traversability and safety. It is desirable to achieve a slope of about 1:4 to 1:6 (i.e. vertical to horizontal dimension ratio) or flatter (4, 5).
[0013] Untreated culvert ends under driveways or median crossings are hazardous to vehicles that have left the roadway (5). AASHTO (American Association of State Highway and Transportation Officials) and Austroads recommend the use of grated culvert safety end treatments for parallel drainage culverts with diameters greater than 900 mm (4,5). At traffic volumes above 13,000 vehicles per day a grated treatment becomes a cost effective safety treatment for culvert diameters greater than 600 mm (4, 5). It is further recommended that multiple adjacent parallel drainage culverts of any diameter have the grated safety end treatments (4). Grates are recommended for cross drainage slopes when the gap exceeds one meter. Multiple cross drainage culverts perpendicular to the road with gaps greater than 750 mm require grating (4). The slope of tube inlet and outlet structures should match the adjacent side slope (4).
[0014] It is recommended that single culverts with diameters of 600 mm or less be chamfered to match the graded side slope of the intersecting road embankment (4,5).
[0015] The problem is that it is unlikely that a small to medium size vehicle with 15 inch wheel rims or less will be able to mount a 600 mm diameter or larger culvert, given that typically the outside diameter of their wheels (i.e. rim and tire) have heights in the range of 600 mm to 660 mm. The additional obstruction of a larger unprotected culvert end or a culvert headwall will make the problem increasingly insurmountable. If a vehicle at speed were to enter and track down the ditch to the culvert it is likely that the vehicle bumper, suspension, or wheel would snag on the culvert end and the vehicle would either arrest or be launched out of control.
[0016] Vehicles with smaller wheels will have an even greater risk as the culvert end hazard is a proportionally greater obstacle. The majority of the light vehicle fleet has 15 inch or smaller wheel rims, with outside wheel diameter heights of less than 600 mm. The culvert end snagging hazard is a growing problem as the proportion of small to medium size vehicles is increasing due to economic and environmental reasons. These vehicles generally have 13 or 14 inch wheels rims, with an outside diameter wheel height of less then 600 mm. The effect of this trend is that increasingly smaller diameter culverts are becoming dangerous snagging hazards.
[0017] The general effect following a culvert end snag at speed will be the further loss of control due to damage to the vehicle's steering and suspension. Often this results in a severe impact on the culvert end or headwall, and/or the catastrophic flipping of the vehicle.
[0018] Current practice uses pre-cast concrete end sections with grates to reduce wheel snagging on the drainage opening. The maximum spacing of grate pipes or bars are set on 600 mm centers.
[0019] These examples are exemplified by the prior art. U.S. Pat. No. 3,587,239 illustrates a culvert construction that is beveled downwardly and outwardly and includes a grate structure of heavy construction overlying and extending the beveled area which, in the event of a vehicle impact allows the vehicle to traverse the culvert upwards, over the inclined grate.
[0020] French application number 2793820 is another example of the use of a protective grate in which the grate is produced at a sloping angle to transition the vehicle over the opening of the culvert.
[0021] A further example of an attempt to solve the problem is U.S. Pat. No. 6,769,662. This example provides a pre-cast safety end for culverts. This culvert end also has a concrete transition that guides the vehicle over the top of the culvert drain entrance to avoid the wheel engaging with the drain entrance.
[0022] All of the known culvert safety ends utilize a rigid system that is designed to withstand the impact of a vehicle and direct the vehicle over the culvert. However, they all suffer from several problems inherent to their design. In particular is the large cost and engineering difficulties associated with making and installing such a system. These structures may require heavy machinery to place the structures in place, or alternatively, large amounts of concrete and/or steel to create the appropriate deflection system. It is also a common problem for culverts and ditches to accumulate debris such as branches, dirt, gravel and other roadside detritus. This accumulation, in conjunction with a sieve like grate as given in U.S. Pat. No. 3,587,239 can cause drain blockages which require extensive and tedious maintenance. Either of these considerations may be impractical for the location for the culvert to be installed.
[0023] What is needed is a safety culvert end that assists vehicles that enter a ditch and are confronted with a culvert, a method to safely transition out of the ditch and culvert without the vehicle becoming snagged on the culvert end.
[0024] It is an object of the invention to provide a culvert safety end that deforms to create a surface that transitions an errant vehicle over the culvert end or to at least provide the public with a useful alternative.
STATEMENTS OF INVENTION
[0025] In a first aspect, the invention provides a culvert end, wherein the culvert end is structurally weakened to allow partial collapse of the upper section of the end on impact loading.
[0026] Preferably the culvert end allows the culvert end to partially collapse under impact loading creating a transitioning surface over the culvert. The impact loading may be by way of a sudden force resulting from an impact by a vehicle. The structural weakening may be by way of one or more failure planes in the culvert end.
[0027] The invention also provides for a culvert end comprising one or more failure planes comprising a slit, perforation, a thinned section, a section of material that is weaker than the culvert or a section of deformable or weakened material.
[0028] The culvert end may comprise one or more side failure planes located on one or both outer sides of the culvert end at a height of a half diameter of the culvert, extending from the end, parallel to the central axis of the culvert.
[0029] In one embodiment the culvert end may also comprise one side failure plane on each side of the culvert end extending from the end parallel to the central axis of the culvert.
[0030] The side failure planes may have a length that is substantially equal to half to four times the diameter of the culvert.
[0031] A further embodiment of the culvert end comprises a top failure plane on the top of the culvert end extending from the end, parallel to the central axis of the culvert.
[0032] The top failure plane may also have a length substantially equal to one quarter to two times the diameter of the culvert.
[0033] The structural weakening of the culvert end may be by way of one or more deformable materials, for example the culvert end may be made from a deformable material. The deformable material may be plastic, ceramic, fiberglass, metal or concrete.
[0034] Examples of suitable deformable plastic materials include Acrylonitrile butadiene styrene, Polyethylene, Polyvinylchloride, Polypropylene, Polyvinylidene fluoride or Polybutylene.
[0035] Examples of suitable deformable metal materials include corrugated aluminum or corrugated steel.
[0036] Examples of suitable deformable concrete materials include Bar-Wrapped or reinforced concrete.
[0037] A particular example of the deformable material is medium or high density polyethylene.
[0038] A further embodiment of the invention provides side failure planes which comprise an angled interface.
[0039] In another embodiment the culvert end according to the present invention provides drainage continuity.
[0040] The present invention also provides for a culvert end capable of being retrofitted to a preexisting culvert.
[0041] Further, the invention also embodies a culvert comprising a culvert end as previously described.
[0042] The culvert or culvert end may also comprise a brow that is thickened.
BRIEF DESCRIPTION OF FIGURES
[0043] The invention will now be described by example only with reference to the figures:
[0044] FIG. 1 shows a side view of an embodiment of a smooth walled culvert end according to the present invention;
[0045] FIG. 2 shows a top view of the culvert end of FIG. 1 ;
[0046] FIG. 3 a shows an end view of the culvert end of FIGS. 1 and 2 ;
[0047] FIG. 3 b shows an end view of the culvert end of FIGS. 1 and 2 when it incorporates an optional thickening or a brow;
[0048] FIG. 4 shows a detail view of an intersecting road cross section showing a typical installation of the culvert safety end of FIGS. 1 to 3 ;
[0049] FIG. 5 shows a perspective view of the culvert end of FIGS. 1 to 4 .
[0050] FIG. 6 a shows a side view of an embodiment of a culvert end incorporating a brow;
[0051] FIG. 6 b shows a top view of an embodiment of a culvert end of FIG. 6 a incorporating a brow;
[0052] FIG. 6 c shows an end view of the culvert end of FIGS. 6 a and 6 b incorporating a brow;
[0053] FIG. 6 d shows a perspective view of an embodiment of a culvert end of FIG. 6 a or 6 b incorporating a brow;
[0054] FIG. 6 e shows a detail view of an intersecting road cross section showing a typical installation of the culvert safety end of FIGS. 6 a to 6 d;
[0055] FIG. 7 a shows a side view of a corrugated culvert end incorporating a brow;
[0056] FIG. 7 b shows a top view of the culvert end of FIG. 7 a;
[0057] FIG. 7 c shows an perspective view of the culvert end of FIGS. 7 a to 7 b;
[0058] FIG. 7 d shows a detail view of an intersection road cross section showing a typical installation of a culvert safety end of FIGS. 7 a to 7 c;
[0059] FIG. 8 a shows an end view of the culvert end having angular slits;
[0060] FIG. 8 b shows a detailed enlargement of the end view FIG. 8 a;
[0061] FIG. 9 a shows a side view of the culvert end incorporating perforations;
[0062] FIG. 9 b shows a top view of the culvert end of FIG. 9 a;
[0063] FIG. 9 c shows a perspective view of the culvert end of FIGS. 9 a to 9 b;
[0000] wherein;
D is the nominal outside diameter;
Ds is the vertical distance from the bottom to the side failure planes;
Dt is the horizontal distance from side to top failure planes;
L is the length of the culvert or culvert extension;
Ls is the length of the side failure planes;
Lt is the length of the top failure planes;
T is the brow thickness; and
W is the tube wall thickness.
DETAILED DESCRIPTION
[0064] The present inventor has found that instead of utilizing a solid rigid structure to transition a vehicle in the event of a crash, this effect can also be achieved by incorporating a weaker structural element into the culvert end. On impact loading by a vehicle in the event of an accident, the upper section culvert end will partially collapse creating a transitioning surface, and enable the vehicle to override and traverse the culvert safety end and transition onto an appropriately graded intersecting road embankment side slope. The transition will facilitate the retention of vehicle control, and avoid the bumper, undercarriage or wheel snagging on the culvert end. This will minimize damage to the vehicle suspension and steering and further loss of control. The smaller the culvert on which the culvert safety end is used, the smoother will be the override transition.
[0065] The term culvert includes, but is not limited to any channel, drain, conduit, tunnel or the like, designed for the purpose of carrying water under a carriageway, for example a road, walkway or railway. In this situation it is also used to refer to a tube used in a road-like environment with at least one exposed end.
[0066] The weaker structural element forming the safety end may be achieved through either a weakening of the structural integrity of the end of the culvert or culvert extension through the manufacturing of predictable collapse mechanisms into it, and/or through being manufactured of a deformable material and/or structure that is adequately weaker than the balance of the main load bearing length of the culvert or extension. The collapsing of the upper weaker structural element forming the end of the culvert or extension creates a transitioning surface that enables the impacting vehicle bumper, under carriage or wheel to be supported and direct the travel of the vehicle upwards to override and traverse it, but not to the extent that the controlled collapse impedes drainage or water flow through the culvert.
[0067] It will be appreciated that any suitable material used in culvert construction, including deformable material, could be used in the present invention. Such a material has to be sufficiently rigid to the normal forces of a culvert, but will deform under sudden impact loading, for example with a vehicle, and provide a transition surface capable of supporting a vehicle's passage. Examples of suitable deformable material may include, but are not limited to, plastic, fiberglass, ceramic, metal or concrete. In particular, plastics, such as Acrylonitrile butadiene styrene, Polyethylene, Polyvinylchloride, Polypropylene, Polyvinylidene fluoride or Polybutylene, metal, such as corrugated aluminum or corrugated steel, concrete, such as Bar-Wrapped or reinforced concrete may be used in the present invention.
[0068] Those skilled in the art will appreciate that some materials are elastically deformable and others are destructively deformable. The present invention is intended to encompass embodiments that encompass both types of deformation. It is further possible to have a culvert end that is partially elastically deformable. This will particularly be the case when certain types of polyethelene pipes are used. The advantage of an elastically deformable, or partially elastically deformable, culvert end is that it allows the pipe to maintain flow of water through the pipe after an impact incident, while maintaining its safety characteristics. Also, the culvert end may be returned to substantially or approximately its original shape following an accident, thereby not requiring a new culvert or end to be installed.
[0069] In addition to the use of a deformable material to create the structural weakening is to include one more failure planes, for example slits, in the culvert end. Such failure planes can be used to ensure that the culvert end deforms in a predicted manner under impact loading, for example, impact with a vehicle; such that the upper section at the end of the culvert will collapse downwards creating a transitional surface that will direct a vehicle upwards and over the culvert end.
[0070] Examples of how the weakening of the upper section of the culvert end can be achieved are shown FIGS. 1 to 9 . The culvert end 1 comprises a tube section 2 having diameter D and length L. As shown in FIGS. 1 , 6 a , 7 a , and 9 a the tube section 2 has side failure planes 3 , comprising a slit, at each side, starting at the end of the tube 2 and extending parallel to the central axis of the tube 2 for a distance Ls. The side failure planes 3 are located at Ds in the horizontal plane at a height of half the diameter D of the tube 2 from the bottom and extend parallel to the central axis of the culvert end. The tube 2 also has a top failure plane 4 ( FIGS. 2 , 6 b , 7 b and 9 b ), starting at the end of the tube 2 and extending parallel to the central axis of the tube 2 for a distance Lt. The top failure plane 4 is located Dt on the upper part of the tube at the top most part of the tube 2 (at a height equal to the diameter of the tube), and extends parallel to the central axis of the tube and with the failure plane substantially equidistant between the side failure planes 3 .
[0071] Under impact with a vehicle, it has been found that the inclusion of the side failure planes 3 and top failure plane 4 in the culvert end 1 causes the front of the upper section of the tube 2 to deform downwards, thereby creating a transitioning surface that deflects the vehicle upwards and away from the culvert. In doing so the collapsing upper section of the tube 2 decreases the likelihood of the vehicle catching or snagging itself the culvert opening, and therefore reducing the likelihood of catastrophic vehicle impact or rolling.
[0072] In one embodiment it has been found that having a Ls substantially equal to the diameter D of the tube 2 and a Lt substantially equal to half the diameter D of the tube 2 provides for the correct collapsing of the upper portion of the culvert end 1 under impact loading.
[0073] For example, in a further embodiment of the invention it has been found that having a Ls substantially equal to two times the diameter D of the tube 2 and an Lt substantially equal to half the diameter of D of the tube provides for the correct collapsing of the upper portion of the culvert end 1 under impact loading.
[0074] However, it will be appreciated that the lengths of Lt and Ls may be varied and still achieve the desired result. It will also be appreciated that the lengths of Lt and Ls can vary depending on the material the culvert end is created from, the diameter of the culvert end, the angle desired for the transition surface and other characteristics that can be determined by one skilled in the art.
[0075] It will also be understood by the skilled person that once the use of a structural weakness to create a transitional plane under impact has been appreciated, the use of other forms to create structural weaknesses, for example the use of slits, perforations, cuts, gaps, or the like, deformable material, localized use of weaker or deformable material, thinner sections in the tube 2 , as well as other arrangements of using one or more failure planes will be possible, that will allow the desired collapsing of the upper section to create a transitional surface under impact. The use of all other structural weakness which allow the upper section of the culvert end to collapse under impact loading fall with in the scope of the present invention.
[0076] FIGS. 6 a to 6 c , 7 a to 7 c and 9 a to 9 c all show different embodiments of the invention with different examples of side failure planes. FIGS. 6 a to 6 c show a straight edged failure plane utilizing a slit, FIGS. 7 a to 7 c show a straight edged failure plane incorporating an angled failure plane and FIGS. 9 a to 9 c show failure planes utilizing perforations. Examples 1 to 6 show a smooth walled embodiment of the invention, the smooth wall can be created utilising any material known to one skilled in the art that can be formed into a pipe. For example, concrete, metal or plastic. FIGS. 7 to 9 show an embodiment of the invention wherein the walls of the culvert end are corrugated. This is particularly embodies by corrugated plastic or corrugated metal. In particular, corrugated polyethylene.
[0077] In a further embodiment, the side failure planes 3 can comprise an angled interface 9 at the side failure planes 3 as shown in FIGS. 8 a and 8 b . This provides a mechanism to allow the upper part of the side failure plane 3 of the culvert end to more easily slide past the lower part of the side failure plane 3 on impact loading. The side failure planes 3 may lie with an interface parallel to each other, however, the angle of the side failure plane may range between 0° from horizontal and 90° from horizontal. In a particular embodiment the upper part of the side failure plane may be cut X between 0° and 90°, more preferably between 20 and 80°, more preferably 40° and 70°, more preferably between 50° and 70°, and most preferably 60° below the plane of horizontal and the lower part of the side failure plane may be cut Y at between 0° and 90°, more preferably between 20 and 85°, more preferably 40° and 82°, more preferably between 60° and 82°, and most preferably 80° below the plane of horizontal.
[0078] As shown in FIGS. 3 b , 6 a to 6 c , 7 a to 7 c , 8 a and 9 a to 9 c , the culvert end 1 can incorporate thickening, or brow 5 , of the tube 2 in the upper portion of the culvert end 1 . This brow increases the contact area for the impacting vehicle to engage and facilitate the safety end collapse mechanism, on culverts or extensions of larger diameters. The brow 5 can also provide strength to the upper portion and ensures the integrity of the transition plane created by the collapse of the upper portion of the tube 2 under impact. On larger diameter tubes, a thickened brow can also assist in the vehicle gaining sufficient traction on the brow to facilitate the desired collapse.
[0079] It will be appreciated that the present invention can be constructed as a continuous length of tubing, which incorporates the structural weakening at either one end or both ends, and constitutes the entire culvert. This provides for a much easier product that can be built as a single unit that can easily be installed when the drain is being constructed. Alternatively, the present invention can be constructed as a shorter end section that can be attached to a culvert, either during construction, or retrofitted to an already existing culvert.
[0080] A culvert end is the end element of a culvert or culvert extension of a similar shape and size to the culvert, so that drainage flow capacity is not unduly compromised. An extension of the same diameter as the culvert could be transitioned to it. An extension with a larger diameter than the culvert could be sleeved over, or transitioned to the culvert. An extension made of a suitable material to provide the necessary safety end performance, and minimize the effects on flow capacity through having thinner walls, could either be sleeved into, or transitioned to the culvert.
[0081] FIGS. 4 , 6 e and 7 d show a cross section of a culvert tube in situ in an embankment of an intersecting road. The embankment 6 has a graded side 7 . In the figures, a culvert end 1 according to the present invention has been retrofitted to a previously exposed end 8 of an existing culvert tube 2 .
[0082] The presently claimed culvert end provides for the benefit that under impact with a vehicle, the vehicle is able to pass safely over the culvert end. This significantly reduces the crash impact forces of striking an unprotected culvert end.
[0083] It also has the benefit that it can be produced easily as a culvert extension, that can be quickly and easily (i.e. less expensive) retrofitted to unprotected culvert end. Furthermore, the culvert extension could be readily replaced if vehicle override impact damage was excessive, with little effect to the main culvert crossing.
[0084] The claimed culvert end also has the advantage that, because the end extends from the bank, it shields the culvert inlets from falling loose material and debris that would impede roadside drainage, as happens with chamfered or grated culvert ends. The absence of a bolted down grated end treatment on a culvert with a safety end will make routine removal of any debris faster and easier (i.e. less expensive). Therefore the present culvert end does not require the same level of maintenance.
[0085] Although the invention has been described by way of example, it should be appreciated that variations and modifications may be made without departing from the scope of the invention. Furthermore, where known equivalents exist to specific features, such equivalents are incorporated as if specifically referred in this specification.
[0086] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of “including, but not limited to.
REFERENCES
[0000]
(1) Bahar G. B, Roadway Departure Crashes: How Can They Be Reduced, ITE Journal, December 2008
(2) France a star in road safety, Road Marking News, April 2008
(3) Crash Analysis System, New Zealand Ministry of Transport, February 2009
(4) Roadside Design Guide, American Association of State Highway and Transportation Officials, 2002
(5) Guide To Road Design Part 6, Austroads, 2009. | The present invention provides for a culvert end, wherein the culvert end is structurally weakened to allow partial collapse of an upper section of the end on impact loading. The culvert end aims to decrease the severity of motor vehicle accidents wherein the culvert has an end that is deformable under impact to create a transitioning surface to reduce the likelihood of the vehicle arresting, catching or snagging itself in the entrance to the culvert. | 4 |
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 invention relates generally to the field of instruments conveyed into subsurface wellbores by armored electrical cable. More specifically, the invention relates to devices for moving such instruments to a selected rotary orientation within a wellbore.
2. Background Art
Many types of instruments are used in wellbores drilled through subsurface rock formations. Such instruments can include, among other devices, sensors for measuring properties of the rock formations outside the wellbore, energy sources for various types of surveying or evaluation, mechanical wellbore intervention tools and directional survey instruments, as non limiting examples. Such instruments may be conveyed along the inside of the wellbore by a technique generally known as “wireline” in which an armored cable having one or more insulated electrical conductors therein is extended into and withdrawn from the wellbore using a winch, and in which the instruments are disposed at the end of the cable.
In some cases, it may be desirable to move the instrument to a selected rotary orientation within the wellbore. Such orientations may include having sensors on the instrument directed toward, for example, the gravitationally upwardmost direction (“high side”) for purposes of surveying the trajectory of the wellbore. Other examples may include having a seismic energy source oriented in the direction of an adjacent wellbore.
Irrespective of the reason for requiring rotary orientation capability, it has proven impractical to provide such capability when instruments are conveyed into a wellbore by wireline.
SUMMARY OF THE INVENTION
A method for rotating a wellbore instrument in a wellbore according to one aspect of the invention includes causing parts of an instrument housing to be sequentially rotationally magnetically attracted to a casing disposed in the wellbore. The housing has a smaller external diameter than an internal diameter of the casing. The sequential rotational magnetic attraction is continued until the instrument housing is oriented in a selected rotational direction.
An apparatus for rotating an instrument in a wellbore according to another aspect of the invention includes a non magnetic housing configured to traverse the interior of the wellbore. The housing has an external diameter smaller than an internal diameter of a casing disposed in the wellbore. A plurality of electromagnets is arranged circumferentially about the interior of the housing and is configured to induce magnetic flux through a wall of the housing when actuated. A controller configured to sequentially rotationally actuate the electromagnets.
Other aspects and advantages of the invention will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an instrument conveyed into a wellbore as it may be used with an example rotator according to the invention.
FIG. 2 shows the instrument, the example rotator and associated devices of FIG. 1 in more detail.
FIG. 3 shows a cross section of one example of a rotator.
DETAILED DESCRIPTION
FIG. 1 shows an instrument 14 conveyed into a wellbore 18 drilled through subsurface rock formations. The wellbore 18 in FIG. 1 includes a steel pipe or casing 16 installed therein. It is only necessary for purposes of using the invention that the casing 16 is ferromagnetic. Other properties of the casing 16 are not intended to limit the scope of the invention. The instrument 14 in the present example can be conveyed through the interior of the casing using armored cable 22 deployed by a winch 20 . Such conveyance is known as “wireline” as explained in the Background section herein. The cable 22 may include one or more insulated electrical conductors for transmitting power to the instrument 14 and communicating signals from the instrument 14 to a recording and control unit 24 disposed at the surface. For purposes of defining the scope of the invention, other conveyance known in the art called “slickline” in which the cable has a cylindrical, smooth exterior surface and may or may not include electrical conductors therein is intended to be within the definition of “wireline.” An example of slickline having electrical conductors therein is described in U.S. Pat. No. 5,122,209 issued to Moore.
The instrument 14 is coupled to the cable 22 using a cable head 26 . The cable head 26 may be coupled to a swivel 28 that enables relative rotation between the cable 22 and the instrument 14 while maintaining electrical communication between the instrument 14 and the cable 22 . The swivel 28 may be coupled to one end of a rotator 10 . The other end of the rotator 10 may be coupled to the instrument 14 , in some examples using a flexible coupling 12 . The flexible coupling 12 may be used to enable the instrument 14 to be moved with respect to the rotator 10 by deflection and/or displacement of the axis of the instrument 14 with respect to the axis of the rotator 10 , while maintaining rotational coupling between the instrument 14 and the rotator 10 . See U.S. Pat. No. 5,808,191 issued to Alexy, Jr. et al. for a description of one example of a flexible coupling, although the type of flexible coupling and whether it is used in any example is not intended to limit the scope of the present invention.
It is also to be understood that the instrument 14 and the rotator 10 may be disposed within the same instrument housing or as part of the same instrument. The description with reference to and the illustration in FIG. 1 are meant only to provide one non limiting example of how to make and use the present invention. Accordingly, the use of a separate rotator and instrument as shown is not a limit on the scope of the present invention.
One example of a type of instrument that may be used with a rotator according to the invention is a directional seismic energy source. Such sources may direct a substantial portion of the seismic energy generated in a single lateral direction, or within a limited range of angle with respect to the source longitudinal axis of the source. In the example shown in FIG. 1 , a seismic receiver 50 may be disposed in another wellbore 18 A, and may be conveyed therein using a second wireline 22 A. One example of such a seismic receiver is described in U.S. Pat. No. 4,715,469 issued to Yasuda et al. In such examples, the seismic energy source if disposed in the wellbore 18 may be rotationally oriented using the rotator 10 so that its signal output is directed toward the other wellbore 18 A.
The instrument 14 , flexible coupling 12 , rotator 10 swivel 28 and cable head 26 are shown in more detail in FIG. 2 . In particular, the rotator 10 may include a substantially cylindrical housing 10 B formed from a non-magnetic material, for example, monel, stainless steel, titanium or an alloy sold under the trademark INCONEL, which is a registered trademark of Huntington Alloys Corporation, Huntington, W. Va. The housing 10 B may include through the wall thereof a plurality of longitudinally extending, circumferentially spaced apart magnet pole shoes 10 A. In other examples, depending on the material from which the housing 10 B is made, its thickness and the amount of torque needed to be generated by the rotator 10 to rotate the instrument, the pole shoes 10 A may not protrude through the wall of the housing 10 B. As will be explained with reference to FIG. 3 , each pole shoe may be associated with one or more electromagnets that may be actuated to cause the rotator 10 to be magnetically attracted to the casing ( 16 in FIG. 1 ). Sequential actuation of the electromagnets ( FIG. 3 ) will cause rotation of the rotator 10 inside the casing ( 16 in FIG. 1 ). The rotator housing 10 B may have an external diameter that is smaller than the internal diameter of the casing ( 16 in FIG. 1 ). Because of the diameter difference between the housing 10 B and the casing, the magnetic rotation of the housing 10 B in the casing will cause the housing 10 B orientation to precess within the casing. That is, the rotational orientation of the housing 10 B will move with respect to the casing as the housing rotates inside the casing in contact therewith. By continuing rotation, the housing 10 B may eventually be oriented in a selected rotational orientation.
An example structure for causing magnetic rotation of the rotator 10 within the casing ( 16 in FIG. 1 ) is shown in cross section in FIG. 3 . The housing 10 B may include a plurality of circumferentially spaced apart pole shoes 10 A as explained above. The pole shoes 10 A may be made from ferromagnetic material such as steel. Each pole shoe 10 A may be associated with one pole of two adjacent ferromagnetic electromagnet cores 30 . The cores 30 may extend longitudinally about the same distance as the pole shoes 10 A and may have end section in approximately the shape of the letter “C” as shown in FIG. 3 . An electromagnet wire coil 32 may be wound longitudinally around the center of each core 30 as shown in FIG. 3 such that the magnetic dipole of each coil 32 is substantially perpendicular to the plane of symmetry (not shown) of each core 30 . The configuration shown in FIG. 3 may have the advantages of generating high magnetic attraction between the pole shoes 10 A associated with the activated electromagnets (each electromagnet consisting of a coil 32 and a core 30 ), while minimizing magnetization of the other pole shoes 10 A, because the C-shape of the core causes magnetic flux to flow in a closed magnetic circuit including the adjacent pole shoes 10 A and the casing ( 16 in FIG. 1 ) in contact with the pole shoes 10 A. Other configurations may include a separate pole shoe for each open end of each core. In principle, the structure of the cores, coils and pole shoes is intended to induce magnetic flux through the wall of the housing 10 B when each coil is energized.
The coils 32 are each connected to a electromagnet switching controller 40 which may be any microprocessor based controller associated with suitable power switching circuitry (not shown separately) to apply electrical current to the coils 32 rotationally sequentially, thus causing rotation of the ones of the pole shoes 10 A that are magnetically attracted to the casing ( 16 in FIG. 1 ). In the example of FIG. 3 , the controller 40 may be in signal communication with a directional sensor 44 so that the rotational orientation of the rotator 10 (and the instrument connected thereto) with respect to a geodetic reference may be determined. It will be appreciated by those skilled in the art that because the rotator 10 is used in ferromagnetic casing, the directional sensor 44 must be of a type that is not dependent on the Earth's magnetic field to establish a geodetic reference. One non limiting example of such a directional sensor is described in U.S. Pat. No. 4,611,405 issued to Van Steenwyk, in which geodetic reference is established using an Earth rate gyroscope. In examples using cable having electrical conductors therein, electrical power and signals between the instrument ( 14 in FIG. 1 ) and the recording unit ( 24 in FIG. 1 ) may be transferred between the cable ( 22 in FIG. 1 ), the controller 40 and other devices by a power conditioner/telemetry device 42 of types well known in the art. The example shown in FIG. 3 in which the controller is disposed inside the rotator is only one example of a device for selectively applying current to the coils to cause the sequential actuation of the electromagnets. In other examples, an individual electrical conductor could be provided in the cable ( 22 in FIG. 2 ) for each coil 32 . Any other configuration that enables selective actuation of the coils may be used consistent with the scope of this invention.
In using the rotator made as explained above, the coils 32 are rotationally sequentially energized, causing the pole shoes 10 A to be rotationally sequentially attracted to the casing ( 16 in FIG. 1 ). Such rotational magnetic attraction causes the rotator 10 to precessionally rotate inside and to contact the interior of the casing. The difference between the internal diameter of the casing and the external diameter of the housing (or the pole shoes 10 A if they are made to extend laterally outwardly from the housing) will determine the amount of precession of the rotational orientation of the rotator 10 with respect to the casing each time the rotator 10 completes a full rotation within the casing. Thus, it may be necessary to rotate the rotator through a number of full rotations inside the casing to provide a selected rotary orientation. In the example shown in FIG. 1 and FIG. 2 , the swivel ( 28 in FIG. 1 ) may be used advantageously to enable the rotator to rotate as much as is required without twisting the cable ( 22 in FIG. 1 ). In some examples, rotation of the rotator 10 may be made smoother by controlling the current in each of the coils 32 so that magnetization is gradually reduced, while magnetization in the adjacent coil is gradually increased. In such examples, there may be current flowing in two or more adjacent coils at any time to optimize the rotation.
In other examples, the rotator may be used for substantially continuous rotation for a selected period of time, for example, to operate a drill, mill or grinding device for wellbore repair or intervention operations. It will be appreciated by those skilled in the art that by selection of a suitable rotator outer diameter for a particular casing internal diameter, the rotator may be provided with selected rotation speed and torque for the particular use intended. Larger rotator diameter will result in lower rotation speed and higher torque, and vice versa for smaller diameters.
A wellbore instrument rotator according to the invention may provide the capability of moving an instrument conveyed along a wellbore by a cable to any selected rotary orientation without the need to rotationally fix any part of the instrument within the wellbore.
While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. | An apparatus for rotating an instrument in a wellbore includes a non magnetic housing configured to traverse the interior of the wellbore. The housing has an external diameter smaller than an internal diameter of a casing disposed in the wellbore. A plurality of electromagnets is arranged circumferentially about the interior of the housing and is configured to induce magnetic flux through a wall of the housing when actuated. A controller configured to sequentially rotationally actuate the electromagnets. A method for rotating a wellbore instrument in a wellbore includes causing parts of an instrument housing to be sequentially rotationally magnetically attracted to a casing disposed in the wellbore. The housing has a smaller external diameter than an internal diameter of the casing. The sequential rotational magnetic attraction is continued as needed. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from previously filed U.S. Provisional Patent Application Ser. No. 61/089,751 filed on Aug. 18, 2008 hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] External beam radiation therapy systems provide beams of high-energy directed into a patient to treat tumors or the like. The size, location, angle and intensity of the beams are determined by a treatment plan based upon the precise measurement of the dose to be delivered to the patient to provide for precise control of the dose to the patient.
[0003] Quantitative accuracy is ensured by periodic calibration of the machine using radiation detectors and phantoms to determine the relationship between the control settings of the machine and actual dose. One type of radiation detector is an ionization chamber in which electrodes are placed on opposite sides of a volume of gas. The gas is ionized by the radiation passing through the chamber volume and the ions are collected on one collector electrode under the influence of a voltage applied across the electrodes.
[0004] Ideally the ionization chamber volume is small compared to the beam size to limit “partial volume” errors that affect the ionization chamber measurement when the volume is not fully irradiated by the measured radiation beam.
[0005] Certain radiation therapy systems, for example, the Gamma Knife® or a linear accelerator configured for stereotactic radiotherapy or radiosurgery, provide extremely small radiation beams, for example, as small as 4 mm. It is difficult to construct ionization detectors that are small enough to avoid partial volume effects while providing desired sensitivity.
SUMMARY OF THE INVENTION
[0006] The present invention provides an ionization chamber having two measurement volumes, one substantially surrounding the other, either or both of which may be larger than the desired measured radiation field. By using the readings from the two chambers of different sizes, it is possible to detect and or correct for the partial volume effects.
[0007] Specifically then, the present invention provides a nested radiation detector system having a first radiation detector being an ionization detector defining a first volume and providing for the detection of ionized gas in the first volume at a first collection electrode and a second radiation detector positioned within the first volume and defining a second volume within the first volume and providing for the detection of radiation in the second volume to produce a signal at a second collection electrode, the first volume being electrically separated from the second volume. Radiation passing through the second volume also passes through the first volume providing current at the first and second collection electrodes from the ionization of gas in the first and second volumes. The second radiation detector may be an ionization detector or a diode detector, a diamond detector, a scintillation detector or the like.
[0008] It is thus a feature of at least one embodiment of the invention to provide a radiation detector system that may be used to detect and correct for partial volume effects where the radiation beam is smaller than one of the ionization chambers or beam misalignment. It is further a feature of at least one embodiment of the invention to provide for the measurement of dose from narrow radiation beams where partial volume effects for reasonably sized ionization detectors will be present.
[0009] At least one of the first and second radiation detectors may provide an outer chamber wall constructed of an air equivalent material.
[0010] It is thus a feature of at least one embodiment of the invention to permit the construction of nested ionization detectors without adversely changing the energy spectrum of the radiation beam such as may unacceptably change the calibration of either detector.
[0011] The outer chamber wall of the first and/or second chamber may be a conductive polymer material or a non-conductive material having an internally applied conductive coating.
[0012] It is thus a feature of at least one embodiment of the invention to provide for simple fabrication of the outer chamber such as from easily machined or molded polymer materials.
[0013] The second volume may be substantially centered within the first volume.
[0014] It is thus a feature of at least one embodiment of the invention to minimize the effects of the angle of the measured beam on the relationship between the measurements of the ionization chambers used for the partial volume correction.
[0015] The first radiation detector may provide an outer chamber wall that is substantially spherical.
[0016] It is thus a feature of at least one embodiment of the invention to minimize the effect of the angle of the radiation beam on the measurements.
[0017] Each of the first and second ionization chambers includes two electrically independent electrodes forming the outer surfaces of the first and second volumes respectively.
[0018] It is thus a feature of at least one embodiment of the invention to permit fabrication of the device using a pre-existing ionization chamber.
[0019] The first radiation detector may provide a hollow shaft leading to the first volume and the second ionization chamber may be removable and slidably received within the hollow shaft against a stop locating the second volume in a predetermined position within the first volume.
[0020] It is thus a feature of at least one embodiment of the invention to permit removal and independent use of the first or second ionization detector when partial volume effects are not at issue.
[0021] The ionization chamber system may further include an electrometer receiving ionization signals from the first and second ionization chambers to provide a correction for at least one of the ionization chambers to accommodate partial volume effects caused by radiation beams having an axial cross-section smaller than a corresponding cross-section of the second volume along the axis.
[0022] It is thus a feature of at least one embodiment of the invention to provide automatic correction of partial volume effects.
[0023] The nested ionization chamber system may further include a third ionization chamber surrounded by the first volume and providing for the detection of ionized gas in a third volume at a third collection electrode, the third volume being isolated from the second volume wherein radiation passing through the first volume also passes through the third volume providing current at the first and third collection electrodes from the ionization of gas in the first and third volumes.
[0024] It is thus a feature of at least one embodiment of the invention to provide for improved correction for partial volume effects through the use of an additional chamber.
[0025] Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a simplified perspective view of an embodiment of an ion chamber system according to the present invention as positioned within a radiation beam;
[0027] FIG. 2 is a schematic representation of one embodiment of the ion chamber system of FIG. 1 showing nested radiation detectors;
[0028] FIG. 3 is a fragmentary, detailed cross-sectional view of the ion chamber system of FIG. 2 ;
[0029] FIG. 4 is a block diagram of an electrometer suitable for use in the present invention;
[0030] FIG. 5 is a plot showing example functional relationships between the calibrated outputs of the nested radiation detectors for different beam widths as may be used to correct for partial volume effects; and
[0031] FIG. 6 is a simplied diagram of an alternative embodiment of the present invention using three radiation detectors.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0032] Referring now to FIG. 1 , the present invention provides an ion chamber system 10 including a detector assembly 12 connected by electrical cables 14 to an electrometer unit 16 . In use, a detector head 18 of the detector assembly 12 may be positioned within a radiation beam 20 to be exposed to the beam 20 . As will be described below, the detector head 18 contains two independent ionization detectors one within the other and each attached to a separate cable 14 . In one embodiment, the electrometer unit 16 may provide for two displays 15 each outputting a dose measurement received from one of the ionization detectors.
[0033] Generally, the radiation beam 20 will have a cross-sectional area 22 taken perpendicular to an axis 25 of the beam 20 along which the radiation propagates. For beams 20 with cross-sectional areas 22 , a beam width 24 may be defined related to the cross-sectional area 22 .
[0034] Referring now to FIG. 2 , the detector head 18 of the detector assembly 12 may provide a substantially spherical outer electrode 26 , for example, enclosing an approximately 100 cm 3 volume. The outer electrode 26 may be constructed of an air equivalent conductive plastic providing radiation absorption characteristics approximating that of air. Such plastic material is commercially available, for example, under the trade name Shonka C552. Alternatively, the outer electrode 26 may be constructed of an air equivalent polymer or a non-air equivalent material having an internal conductive coating. This outer electrode 26 may be connected to ground potential at an internal power supply to the electrometer unit 16 .
[0035] The outer electrode 26 may fit around a second electrode 28 providing a cylindrical tube 30 terminating with a hemispherical portion 32 . The hemispherical portion 32 preferably describes a portion of a sphere where the sphere has a common center with a sphere describing the outer electrode 26 . The second electrode 28 may be a conductive material or conductive layer on the outer surface of an insulating support. The conductive element of this second electrode 28 will be connected through a current sensor 40 to a power source 42 of high voltage electricity, for example, at 300 volts. Together the outer electrode 26 and second electrode 28 provide a first ionization detector 53 sensitive to the volume 52 between the outer electrode 26 and second electrode 28 .
[0036] The second electrode 28 may in turn fit around a third electrode 44 conforming in profile to the second electrode 28 but with smaller dimensions to fit therein. The third electrode 44 may thus also provide a tubular portion 46 capped by a hemispherical portion 48 also describing a portion of a sphere centered on the center of the sphere describing the outer electrode 26 . The third electrode 44 encloses, for example, a volume of approximately 0.007 cm 3 . The third electrode 44 may also be a conductive material or a conductive layer on an insulating support, and in either case is connected to ground.
[0037] Coaxially centered within the tubular portion 46 of the third electrode 44 is a conductive wire electrode 49 terminating substantially at a center of the sphere describing the outer electrode 26 . This wire electrode 49 is connected through a second current sensor 50 to a source of high voltage from power source 42 . Together the third electrode 44 and wire electrode 49 provide a second ionization detector 55 sensitive to the volume 54 between the third electrode and wire electrode 49 and within the volume 52 but isolated therefrom to prevent exchange of electrons therebetween.
[0038] It will be understood that electrons formed in a gaseous volume 52 inside the outer electrode 26 and outside the second electrode 28 will migrate to be collected by the second electrode 28 to be measured by current sensor 40 . Similarly, electrons formed in a volume 54 within the third electrode 44 will be collected by the wire electrode 49 and measured by current sensor 50 .
[0039] The current readings by current sensors 40 and 50 provide an indication of the dose of radiation passing through the respective volumes 52 and 54 according to principles well understood in the art.
[0040] Referring now to FIG. 3 , in construction, the outer electrode 26 may be formed from two interfacing hemispherical half shells 51 and 56 may be adhered together with conductive adhesive, or mechanically and conductively joined. Shell 51 may be threadably attached to a stem 57 extending radially therefrom and providing support for the detector assembly 12 , as shown in FIG. 1 , by means of a stand 58 or the like. Attached to the stem is an interdetector wall 60 having an outer dimension conforming generally to that of second electrode 28 and in the preferred embodiment being an insulating material with an outer conductive coating or conductive material 62 .
[0041] A triaxial cable 64 , forming one of the cables 14 , may be received through an offset bore in the stem 57 with its innermost conductor 66 electrically attached to the conductive coating or conductive material 62 and its outer shield braid 68 attached to a conductive portion of shell 51 and its inner shield braid (not shown) attached to a conductive inner electrode 27 .
[0042] A separate ionization probe 70 may have its stem 72 inserted in a central bore in stem 57 to slide therein to stop against the inner surface of the interdetector wall 60 to be properly positioned within the volume described by outer electrode 26 . This probe 70 , for example, may be a standard ionization probe such as the model A16 Exradin Microchamber ionization chamber manufactured by Standard Imaging, Inc. of Middleton, Wis. or its equivalent.
[0043] The probe 70 provides the wire electrode 49 centered within a housing 74 nesting within the interdetector wall 60 . The housing 74 have a conductive inner surface forming the third electrode 44 and attached to an outer shield braid 76 of a triaxial cable 78 forming a second of the cables 14 . The center conductor of the triaxial cable 78 may provide for the wire electrode 49 and an inner shield braid 77 may attached to an electrode 79 similar in function to electrode 27 described above.
[0044] Referring now to FIG. 5 , the detector assembly 12 may provide for accurate dose measurements of radiation beams 20 of various beam widths 24 a - 24 c including those (beam width 24 b and 24 c ) that do not fully irradiate the volumes 52 and/or 54 . Such beams would be expected to cause partial volume effects that occur when the volume of an ionization detector is not fully irradiated by the radiation beam. Partial volume effects are caused by either or both of a tailing off of the intensity 21 of the beam 20 at the edges of the beam 20 and a decrease in the volume of gas within the detector that may interact with radiation so as to generate ionized current. These partial volume effects may be compensated for mathematically through the measurements made by the detector assembly 12 .
[0045] The process of correction for partial volume effects may begin with an empirical or theoretical modeling of the operation of the detector assembly 12 with a range of widths 24 of beams 20 including, for example, beam width 24 a that fully irradiates the entire volumes 52 and 54 of the ionization detectors 53 and 55 of detector assembly 12 , a beam width 24 b that fully irradiates all of volume 54 but only partially irradiates volume 52 , and beam width 24 c that partially eliminates both volumes 52 and 54 . In each of these situations, two readings may be collected from the detector assembly 12 using electrometer unit 16 .
[0046] These readings are then corrected or calibrated for temperature, pressure, a geometric calibration factor, and other factors known in the art, excluding partial volume effects. The calibrated readings may produce reading D 1 from the ionization detector 53 associated with volume 52 and reading D 2 from the ionization detector 55 associated with volume 54 . These readings may be displayed on displays 15 of electrometer unit 16 .
[0047] For large beam widths 24 a, shown in FIG. 5 as those greater than 60 mm, a ratio of the two dose readings (i.e., D 1 /D 2 ) as a function 80 of beam width 24 will be constant and have a value of unity reflecting the fact that neither ionization detectors 53 and 55 are subject to partial volume effects and are fully and correctly calibrated.
[0048] This ratio will start to drop as the beam width narrows to width 24 b and thus fails to fully irradiate volume 52 causing a partial volume decrease in the value of D 1 with respect to dose D 2 as a function 82 of beam size. This region may, for example, extend between 8 mm and 60 mm of beam width 24 b. The function 82 is related to the characterization of detector 53 .
[0049] For small beam widths 24 c, the ratio D 1 /D 2 will be a different function 84 of beam width 24 driven by partial volume decreases in the values of both D 1 and D 2 . The function 84 is related to the characterizations of detectors 53 and 55 .
[0050] This collected data of functions 80 , 82 and 84 may then be used to detect and/or correct for partial volume effects during calibration of the radiation therapy machine. In this process, the detector assembly 12 may be used to collect data of D 1 and D 2 for a known beam size W. In a first step, the ratio of the measured readings D 1 and D 2 may be taken and compared to the ratio indicated by the previously determined functions 80 , 82 and 84 (depending on the beam size) using a preprepared chart or table similar to that described with respect to FIG. 5 . If the indicated ratio for the beam size does not match, an alignment problem may exist in which the beam 20 is not centered on the volume 54 . In such cases the ratio will be smaller than suggested by FIG. 5 . The process may end at this point if alignment is the only issue.
[0051] If the alignment is correct, the values of D 1 and D 2 may be corrected. In a simple example of this correction process, the ratio of D 1 /D 2 taken from a chart similar to FIG. 5 (based on known beam width) is simply multiplied by the reading of D 2 to obtain a corrected value of D 2 without or with reduced partial volume effects.
[0052] Referring now to FIG. 4 , the above calculations (and the data of a table per FIG. 5 providing functions 80 , 82 and 84 ) may be incorporated into a computerized electrometer unit 16 . Such an electrometer unit 16 receives signals over cable 14 from each of the ionization detectors 53 and 55 at the current sensors 40 and 50 as described before as powered by power source 42 . The measured currents may be provided to analog to digital converters 90 which provide data through a common bus 92 to a processor 94 . The processor 94 may communicate with a memory 96 holding a stored program 98 incorporating the calculations described above. Information about the measurement (beam width W) may be entered through a keyboard 104 , touchscreen or other method and the calculated actual dose corrected according to the equations described above may be presented on graphic display terminal 102 . Both the graphic display terminal 102 and the keyboard 104 may connect to the bus 92 via interface 100 .
[0053] Referring now to FIG. 6 , improved accuracy may be obtained by the use of more than one concentric ionization chamber, for example, by adding a third ionization detector 106 within ionization detector 53 and the addition of an additional current sensor 108 to the electrometer unit 16 this arrangement allows data from this detector 106 to be used to augment that collected by the other detectors 53 and 55 .
[0054] It should be understood that the invention is not limited in its application to the details of construction and arrangements of the components set forth herein. The invention is capable of other embodiments and of being practiced or carried out in various ways. Variations and modifications of the foregoing are within the scope of the present invention. It also being understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. | Nested ionization chambers provide independent measurements of a radiation beam that does not fully irradiate the volume of one or both chambers. By mathematically combining these independent measurements, partial volume effects caused by a change in ionization detector calibrations when the full detector volume is not irradiated by the radiation beam, may be decreased, providing more accurate measurement of extremely small radiation beams. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 14/209,618 filed Mar. 13, 2014, which claims priority benefit of U.S. Provisional Application No. 61/788,733 filed Mar. 15, 2013, reference of which is hereby made in their entirety.
FIELD OF THE INVENTION
[0002] The present invention generally relates to flush valve actuators.
BACKGROUND OF THE INVENTION
[0003] Flush valves are well known in the art. Although many different types of flush valves are known, two types of flush valves that are commonly used rely upon an auxiliary valve to relieve a pressure chamber to allow the main valve to open for a flush. For example, see U.S. Pat. Nos. 5,881,993, 6,913,239 and 7,980,528 incorporated herein by reference. In order to initiate a flush cycle, that is, to flush the fixture, the auxiliary valve must be unseated. Typically this is accomplished by the use of a gland that extends from an auxiliary valve member. Engaging the gland, such as by striking the side of the gland, will tilt the auxiliary valve member off of the valve seat. As the flush cycle proceeds, the auxiliary valve member reseats allowing the pressure chamber to repressurize causing the main valve to close. Although typical flush valves have been designed to provide a single flush volume, dual mode flush valves have become increasingly important as a way to conserve water. Dual mode flush valves provide the user the ability to select between a higher volume flush and a lower volume flush.
[0004] In general, two types of actuation mechanisms are known in the art: manual and automatic. Manual actuation is accomplished through a user initiated process, traditionally by interaction with a mechanical handle. Automatic actuation is accomplished through the use of sensors to determine when a user is present and to actuate the flush valve without the need for direct user initiation, for example when the user has completed usage of the fixture.
[0005] There is a need to combine the water conservation of a dual mode flush valve with the reliability of a manual actuation and the ease of use and hygiene of automatic actuation.
SUMMARY OF THE INVENTION
[0006] One implementation of the invention relates to an automatic actuation assembly for a flush valve. An actuator assembly housing is provided with a mechanism assembly disposed therein. The actuator assembly housing has a receptacle for engaging with a flush valve, the receptacle comprising an outer ring disposed about a receptacle plunger passage. A retention flange is engageable with the receptacle. The flush valve further includes a plunger having a plunger head at an outer end and a shank extending there from to an inner end, the plunger head disposed within the housing and the plunger shank axially slidable in the receptacle plunger passage.
[0007] Another implementation of the invention relates to an automatic actuation assembly for a flush valve. An actuator assembly housing includes a sensor aperture. A sensor assembly is positioned adjacent the sensor aperture and has a first angled emitter and a second angled emitter and an angled receiver sensor. The first angled emitter and the second angled emitter are non-parallel and non-perpendicular to a vertical longitudinal plane of the actuator assembly housing. The sensor and at least one emitter are at an angle with respect to each other, the sensor receiver is positioned to not receive rays emitted by the at least one emitter that are specularly reflected.
[0008] Another implementation of the invention relates to an automatic flush actuation assembly comprising an actuator assembly housing and a mechanism assembly disposable therein. The housing has a housing plunger passage. The actuation assembly further comprises a plunger having a plunger head at an outer end and a shank extending there from to an inner end, the plunger head disposed within the housing and the plunger shank axially slidable disposed in the housing plunger passage. The mechanism assembly includes a mechanism frame supporting a gear train assembly. The gear train assembly includes a motor coupled to at least one gear and a roller system. The roller system includes a support gear and one or more rollers positioned a distance from the center of the support gear rotatable cam. The roller system is positioned adjacent the plunger for engagement of the plunger head. The actuation assembly further comprises a manual actuation assembly at least partially disposed within the actuator assembly housing, the manual actuation assembly including a face plate having a button coupled to a manual actuation arm, the manual actuation arm positioned adjacent the plunger and engageable with the plunger when the button is depressed.
[0009] Another implementation of the invention relates to a flush valve assembly comprising a valve body having a diaphragm assembly disposed therein with a stem extended therefrom. An actuator assembly housing is provided with a mechanism assembly disposable therein. The actuator assembly housing has a receptacle for engaging with the valve body, the receptacle comprising an outer ring disposed about a receptacle plunger passage. A retention flange engageable with the receptacle and a nut retained between the retention flange and the actuator assembly housing, the nut engageable with a handle boss of the valve body. A plunger is included having a plunger head at an outer end and a shank extending there from to an inner end, the plunger head disposed within the housing and the plunger shank axially slidable in the receptacle plunger passage. A bushing is at least partially disposed in the handle boss, the bushing having a bushing plunger passage for slidably receiving the plunger. The mechanism assembly includes a mechanism frame supporting a gear train assembly and a roller system including one or more rollers adjacent the plunger head. A manual actuation assembly is at least partially disposed within the actuator assembly housing, the manual actuation assembly including a face plate having a button coupled to a manual actuation arm, the manual actuation arm positioned adjacent the plunger and engageable with the plunger when the button is depressed. The plunger is engageable with the valve gland by rotation of the rollers to engage the plunger head for lateral movement of the plunger or actuation of the manual actuation arm to engage the plunger head for lateral movement.
[0010] Additional features, advantages, and embodiments of the present disclosure may be set forth from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the present disclosure and the following detailed description are exemplary and intended to provide further explanation without further limiting the scope of the present disclosure claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The foregoing and other objects, aspects, features, and advantages of the disclosure will become more apparent and better understood by referring to the following description taken in conjunction with the accompanying drawings, in which:
[0012] FIG. 1A is a partial section through a diaphragm valve body; FIG. 1B is a section through a piston valve body.
[0013] FIG. 2 is an exploded perspective view of a side mount actuator assembly, a dual mode bushing, and the valve body.
[0014] FIG. 3A is a left side (proximate the valve body) perspective view of a side mount actuator assembly with the retention flange and nut shown in exploded perspective;
[0015] FIG. 3B is a right side (distal the valve body) perspective view of a side mount actuator assembly with the actuating assembly housing, plunger, mechanism assembly, and battery assembly shown in exploded perspective.
[0016] FIG. 4A is a top view of a mechanism assembly; FIG. 4B is a proximate perspective view of a mechanism assembly; FIG. 4C is a side view of a mechanism assembly; FIG. 4D is an exploded distal perspective view of a mechanism assembly; FIG. 4E illustrates an implementation of an second arm of the mechanism assembly.
[0017] FIG. 5A is an exploded view of the motor gear train assembly, the mechanism assembly frame, and the support plate; FIG. 5B is an exploded view of the roller system.
[0018] FIG. 6A is an exploded view of a manual actuation assembly faceplate having one button; FIG. 6B is an exploded view of a multibutton manual actuation assembly faceplate.
[0019] FIG. 7 is an exploded view of a battery assembly.
[0020] FIG. 8A is a perspective view of a plunger in accordance with one embodiment; FIG. 8B is a cross-section view of the plunger of FIG. 8A along line 8 B- 8 B.
[0021] FIG. 9A is a schematic sectional representation of one embodiment of a bushing of the present invention, showing the plunger travel for a full flush; FIG. 9B is a schematic sectional representation of one embodiment of a bushing of the present invention, showing the handle and plunger travel for a partial or reduced volume flush with the angled illustrated as exaggerated for clarity regarding the relative movement.
[0022] FIG. 10A is a proximate end view of a side mount actuator assembly;
[0023] FIG. 10B is a horizontal cross-sectional along line 10 B- 10 B of FIG. 10A ; FIG. 10C is a vertical cross-sectional along line 10 C- 10 C of FIG. 10A .
[0024] FIG. 11 is a vertical cross-section of a side mount actuator assembly affixed to a valve body with a bushing disposed there between.
[0025] FIG. 12A is a side-view of a down-looking emitter for higher mounting installations; FIG. 12B is a side-view of an up-looking emitter for lower mounting installations;
[0026] FIG. 12C is a top-view of the sensor unit for a right hand (facing the fixture) mounting; FIG. 12D is a top-view of the sensor unit for a left hand (facing the fixture) mounting; FIG. 12E illustrates a top-view of a typical perpendicular emitted beam from a sensor unit.
[0027] FIG. 13 illustrates a typical perpendicular emitted beam from a sensor unit to a highly reflective surface, such as a shiny door.
[0028] FIG. 14A illustrates an angled emitted beam from the sensor unit to a highly reflective surface, such as a shiny door and the reflection of same; FIG. 14B illustrates an angled emitted beam from the sensor unit to a typical restroom fixture user wearing typical fabrics and the diffuse reflection of the same.
[0029] FIG. 15A illustrates an embodiment utilizing a transreflective filter; FIG. 15A illustrates an exploded view of the sensor unit; FIG. 15B illustrates a cross-section along the longitudinal axis of the sensor unit; FIG. 15C illustrates a cross-section along the lateral axis of the sensor unit, with an inset close-up of the circled region.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and made part of this disclosure.
[0031] A flush valve of, or for use with certain embodiments of the present invention may be of a known type, such as, but not limited to a diaphragm valve as generally described in U.S. Pat. No. 7,980,528 incorporated herein by reference, or a piston valve as generally described in U.S. Pat. No. 5,881,993 or U.S. Pat. No. 6,913,239 incorporated herein by reference. With reference to FIGS. 1A and 1B , the flush valve 1 includes a valve body 10 having an inlet 12 and an outlet 14 and a main valve 16 a ( FIG. 1A ), 16 b ( FIG. 1B ) disposed there between for controlling the flow of water through the flushometer. When installed the inlet 12 is connected to a water supply [not shown] and the outlet 14 is connected to a fixture 5 ( FIG. 12A ) such as a toilet. The valve body 10 also typically includes a handle opening 15 .
[0032] The main valve 16 (typically a diaphragm assembly 16 a ( FIG. 1A ) or a piston assembly 16 b ( FIG. 1B )) comprises a valve seat 26 formed at an upper end of a barrel 28 and a valve member 18 (e.g., diaphragm 18 a or piston 18 b ). With continued reference to FIG. 1A , the barrel 28 forms a fluid conduit connecting the valve seat 26 with outlet 14 . A pressure chamber 50 is provided within the valve body 10 , above the main valve seat 26 . The pressure chamber 50 is pressurized by the line pressure from the inlet 12 and retains the valve member 18 , such as a diaphragm 18 a or piston 18 b , against the main valve seat 26 . An auxiliary or relief valve 30 , having an auxiliary valve head 31 and auxiliary valve seat 40 , is provided between the pressure chamber 50 and the outlet 14 to controllably seal the pressure chamber 50 . Opening of the auxiliary valve 30 vents the pressure chamber 50 due to the relatively higher pressure in the pressure chamber 50 compared to the outlet 14 . A bottom surface of the valve member 18 is exposed to the inlet 12 , which is pressurized, and, when the pressure chamber 50 is vented, the pressurized inlet water causes the main valve 16 to open, allowing flow of water from the inlet 12 to the outlet 14 over the main valve seat 26 . By-pass valves 54 place the pressure chamber 50 in communication with the inlet 12 , allowing repressurization of the pressure chamber 50 when the auxiliary valve 30 closes. The repressurization of the pressure chamber 50 reseats the main valve 16 , ending the flush cycle.
[0033] With reference to FIG. 1A , the auxiliary valve 30 typically includes a valve stem 32 that extends below the main valve seat 26 and is adjacent the handle opening 15 in the valve body 10 . The valve stem 32 may include a telescopically carrying movable gland 34 . It should be appreciated that the gland 34 allows the auxiliary valve 30 to close even where the flush valve is still being actuated (for example, a manual handle 17 being depressed). The valve stem 32 , or specifically, gland 34 , is positioned for contact by a plunger 36 . The plunger 36 (see FIG. 1B ) includes a plunger head 37 and a plunger shank 38 extending there from. The plunger head 37 generally has a larger perimeter than the plunger shank 38 . The plunger shank 38 opposite the plunger head 37 is configured to engage the valve stem 32 . The plunger 36 is slidably positioned in a bushing 65 , which is typically disposed within the handle opening 15 of the valve body 10 . Actuation of the plunger 36 imparts lateral movement to the plunger 36 to slide in the bushing 65 and engage the valve stem 32 . The auxiliary valve 30 is opened by engaging the valve stem 32 to tilt an auxiliary valve member 31 , typically a disk, off the auxiliary valve seat, 40 .
[0034] A typical mechanism for actuating the plunger 36 is the manual handle 17 , shown in FIGS. 1A and 1B . The handle 17 may be retained on the valve body 10 by a nut 39 , such as the embodiment illustrated in FIG. 1A wherein the nut 39 captures a handle socket 60 that retains a portion of the handle 17 and the plunger 36 . Alternatively, the socket 60 and nut 39 may be a single component as illustrated in FIG. 1B .
[0035] For diaphragm assembly valves, an embodiment of which is shown in FIG. 1A , the valve member 18 includes a diaphragm 18 a peripherally held to the valve body 10 by an inner cover 20 . The diaphragm 18 a is seated upon a shoulder 22 at the upper end of valve body 10 . The inner cover 20 may secure a peripheral edge 52 of the diaphragm 18 a in this position. An outer cover 24 is affixable to the body, such as by threading, to hold the inner cover 20 in position. The diaphragm assembly 16 a , in addition to diaphragm 18 a and the auxiliary valve 30 , may include a retaining disk 40 , a refill ring 42 and a flow control ring 44 . The underside of the retaining disk 40 is attached to a collar 46 , which in turn is attached at its exterior to a guide 48 which carries the refill ring 42 . The above described assembly of elements firmly holds the diaphragm 18 a between the upper face of the refill ring 42 and a lower facing surface of the collar 46 . Above the diaphragm assembly 16 a is a pressure chamber 50 which maintains the diaphragm assembly 16 a in a closed position when the flush valve 1 is not in use.
[0036] As is known in the art, when the handle 17 is operated, the plunger 36 will contact gland 34 , tilting the auxiliary valve 30 off its seat on the retaining disk 40 . This will permit the discharge of water within the pressure chamber 50 down through the guide 48 . Inlet pressure will then cause the diaphragm 18 a to move upwardly off the main valve seat 26 , permitting direct communication between the inlet 12 and the outlet 14 through the space between the bottom of the diaphragm assembly 16 a and the main valve seat 26 . The raising of the diaphragm 18 a also lifts the auxiliary valve gland 34 , allowing it to clear the plunger 36 even if the user has held the handle 17 in an actuated position. Once the gland 34 clears the plunger 36 the auxiliary valve 30 reseats on the auxiliary valve seat 40 , such as the diaphragm 18 a seating on the retaining disk 40 a . As soon as this operation has taken place, the pressure chamber 50 will begin to fill through the by-pass valves 54 in the diaphragm assembly 16 a . As flow continues into the pressure chamber 50 , the diaphragm 18 a will move back down toward the main valve seat 26 and when it has reached that position, the flush valve 1 will be closed.
[0037] Piston assemblies work in a generally similar manner but having a piston rather than a diaphragm for sealing the main valve 16 . One embodiment of a piston assembly is illustrated in FIG. 1B . The main valve 16 is a piston assembly 16 b and the main valve member 18 is a piston 18 b . The actuation mechanism engages the plunger 36 , which contacts the valve stem 32 of the auxiliary valve 30 . This allows the pressure chamber 50 to evacuate and the piston 18 b to unseat from the main valve seat 26 , opening the flush valve 1 .
Side Mount Actuator Assembly
[0038] In one embodiment, a side mount actuator assembly 100 is provided for removable connection to the valve body 10 . FIGS. 2, 3A, and 3B illustrate an embodiment wherein the side mount actuator assembly 100 includes an actuator assembly housing 110 configured to removably connect to the valve body 10 and having disposed therein a mechanism assembly 200 . In one embodiment, the actuator assembly housing 110 serves to support and contain one or more of an automated actuation assembly 220 ( FIG. 4C ) and a manual actuation assembly 400 ( FIG. 4D ). In one embodiment, the actuator assembly housing 110 engages directly with the valve body 10 of a flush valve mounting to the side of the valve body 10 at the handle opening 15 .
[0039] The actuator assembly 100 includes a proximate portion 111 that is generally proximate the flush valve 1 when the actuator assembly 100 is attached to a valve body 10 . The actuator assembly 100 further includes a distal portion 112 general opposite the proximate portion 111 . It should be appreciated that the proximate portion 111 and the distal portion 112 may be understood to refer to general areas of the actuator assembly 100 . In one embodiment, the structures described in greater detail herein are positioned on or within the actuator assembly housing 110 such that the actuator assembly 100 is ambidextrous with regard to the mounting side of the valve body 10 , allowing for “left hand” or “right hand” installations.
[0040] In one implementation, the bushing 65 and/or the receptacle 120 may include a bushing alignment feature 173 , such as corresponding features, to allow for alignment of the bushing 65 , for example a dual flush bushing 66 as described herein, within the receptacle 120 . That is, the dual mode bushing 66 and the receptacle 120 are “keyed” to ensure proper alignment of the dual mode feature of the bushing 66 . One embodiment includes an alignment groove 174 on an interior portion of the outer ring 121 for engaging a protrusion 173 of the dual mode bushing 66 . It should be appreciated that the protrusion 173 may be utilized with a dual mode bushing 66 as described further herein to allow orientation of the bushing 72 in relation to the actuator assembly 100 and valve body 10 to effectuation the desired dual mode flush volumes. The corresponding features may include a protrusion [not shown] on the receptacle 120 and a groove [not shown] on the bushing; 66 or such similar arrangements.
Connection Mechanism
[0041] The actuator assembly 100 is removably connectable with the valve body 10 . In one embodiment, best shown in FIGS. 2, 3A, 10A -C, and 11 , a receptacle 120 extends from the proximate portion 111 of the housing 110 for engaging with the valve body 10 . The receptacle 120 includes an outer ring 121 ( FIG. 3A ) that extends from the housing 110 . The receptacle 120 has a receptacle plunger passage 124 ( FIG. 3A ) that is configured to allow a portion of the plunger 36 to pass through the housing 110 .
[0042] In one implementation, the outer ring 121 further includes a receptacle 120 retention flange 130 , which may be a raised portion, for example having a larger outer diameter than the adjacent outer ring 121 . The retention flange 130 may be a separate component removable, preferably selectively removable via a tool, from the receptacle 120 such as a retaining ring. The retention flange 130 may serve to secure the nut 39 to the outer ring 121 , and thus to the actuator assembly 100 . In one embodiment, the outer ring 121 includes an outer ring groove 132 circumscribing the outer ring 121 . The retention flange 130 may be a component removable from the outer ring 121 and that is engageable with the outer ring 121 by being partially seated within the outer ring groove 132 . The retention flange 130 may be, but is not limited to, a rigid, such as metal, ring or clip, or a elastic gasket or such, for example having a barbed shape for allowing passage of the nut 39 in one direction but retaining the nut 39 against removal in the other direction.
[0043] In one embodiment, the nut 39 is disposable on the receptacle 120 , captured between the housing 110 and the retention flange 130 to retain the nut 39 on the actuator assembly 100 . In one embodiment, the nut 39 includes a threaded interior surface 41 that is engageable with a threaded handle boss 19 on the outer surface of the handle opening 15 . Engaging the nut 39 to the handle boss 19 secures the actuator assembly 100 to the valve body 10 . In one embodiment best illustrated in FIG. 11 , when assembled, as the nut 39 is threaded onto the handle boss 19 , the nut 39 moves toward the retention flange 130 , on the receptacle 120 , as the receptacle 120 engages the dual mode bushing 66 and secures the dual mode bushing 66 between the end of the receptacle 120 (and the entire actuator assembly 100 ) and the edge of the handle boss 19 .
[0044] In certain embodiments, the receptacle 120 is configured to engage with the dual mode bushing 66 and the valve body 10 . FIG. 11 illustrates a cross-section view of one embodiment of a valve body 10 , dual mode bushing 66 , and actuator assembly 100 assembled with the actuator assembly 100 retained on the valve body 10 and the plunger shank 38 extending from the actuator assembly 100 through the dual mode bushing 66 to adjacent the gland 34 . Specifically, in one embodiment, the dual mode bushing 66 is at least partially disposed within the handle opening 15 of the valve body 10 and the receptacle 120 engages one or more of the dual mode bushing 66 or the valve body 10 . In the embodiment illustrated in FIG. 3A , the receptacle 120 comprises an outer ring 121 and an inner ring 122 circumscribed by the outer ring 121 with a receptacle annular gap 123 there between for receiving the skirt 70 of the dual mode bushing 66 . The receptacle plunger passage 124 is provided in the inner ring 122 . The bushing 65 , such as illustrated with respect to a dual mode bushing 66 in FIGS. 9A-9B , may include an outer skirt 70 having an annular flange 71 and a bushing central sleeve 68 defining a bushing plunger passage 67 , with a bushing annular gap 69 there between. In such embodiments, the bushing 65 and receptacle 120 form a “nesting” arrangement. It should be appreciated that this arrangement aids in stabilizing and securing the connection of the actuator assembly 100 to the valve body 10 . The actuator assembly 100 and the dual mode bushing 66 /valve body 10 , in one embodiment, engage in more than a single plane.
[0045] In one implementation, when the actuator assembly 100 is affixed to a valve body 10 with dual mode bushing 66 , the bushing outer skirt 70 is partially disposed within the receptacle annular gap 123 between the outer ring 121 and inner ring 122 . The receptacle inner ring 122 is partially disposed within the bushing annular gap 69 between the bushing outer skirt 70 and the bushing central sleeve 68 . The bushing plunger passage 67 and the receptacle plunger passage 124 substantially align such that the plunger is slidably and tiltably disposed within the dual mode bushing 66 and actuator assembly 100 . The receptacle plunger passage 124 and the dual mode bushing 66 align to allow the plunger shank 38 to pass there through. In one embodiment, the plunger 36 has a longer shank 38 than typical prior art manual actuation devices to accommodate the distance from the valve stem 32 to the interior of the actuator assembly housing 110 where the plunger head 37 must be disposed.
Mechanism Assembly
[0046] The mechanism assembly 200 is disposable within the housing 110 . The mechanism assembly 200 includes the mechanism for actuating the plunger 36 . In one embodiment illustrated in FIG. 3B , the mechanism assembly 200 is removable from the distal portion 112 of the housing 110 , such as where the housing 110 includes an open side for accommodating the mechanism assembly 200 . The mechanism assembly may be fixed to the housing 110 via fasteners 190 , such as screws or bolts. A portion of the mechanism assembly 200 may form an exterior surface 447 of the actuator assembly 100 as illustrated in FIG. 2 .
Automated Actuation Assembly
[0047] One embodiment of the mechanism assembly 200 includes an automated actuation assembly 220 . FIGS. 4A-D illustrate an embodiment of the mechanism assembly 200 . An automated actuation assembly 220 includes a mechanism assembly frame 221 for supporting the structures of the automated actuation assembly 220 . The automated actuation assembly 220 further includes a printed circuit board (PCB) 230 for interconnecting various electronic components. The electronic components may include a sensor unit 300 and a motor and gear train assembly 240 . The PCB 230 may be supported by PCB supports 231 elevating the PCB 230 above the motor and gear train assembly 240 . The sensor unit 300 may be placed on the PCB 230 such that the sensor unit 300 is positioned to correspond with a sensor aperture 360 in the housing 110 .
[0048] In one embodiment, the motive force for the automated actuation assembly 220 is provided by a motor 241 as part of the motor and gear train assembly 240 , which is shown in FIGS. 4A, 4C and 4D and in greater detail in FIG. 5A . In one implementation, the motor 241 converts electrical energy to rotational energy. The motor 241 is coupled to a gear train 242 comprising of one or more gears 243 for translating the rotational energy of the motor 241 to one or more rollers 510 . The one or more gears 243 may be secured by a corresponding pin 244 , which itself may be secured to the frame 221 or the support plate 280 . Rotation of the motor 241 , such as a traditional small electric motor spinning a drive shaft, rotates a gear 243 in the gear train 242 . The gear train 242 interacts with the plunger 36 to convert the rotation motion of the motor 241 into linear motion of the plunger 36 to engage the valve stem 32 .
Sensor Unit
[0049] The sensor unit 300 may be included for embodiments utilizing an automatic actuation feature. The sensor unit 300 is configured to controllably engage the motor 241 to actuate the plunger. Because automatic flush valves are frequently placed in water closets, or the like, opposite a door, it has been observed that certain features of the door may cause poor performance of the sensor unit 300 . FIG. 13 illustrates a typical sensor unit 57 that provides a perpendicular infrared (IR) beam 58 from the sensor unit 57 to a highly reflective surface, such as a highly reflective door 56 . As can be seen, the door 56 tends to specularly reflect the IR beam 58 back. Because of the proximity of the emitter and the sensor within the sensor unit 57 , the reflected IR (in particular, the major rays) that is sensed by the sensor unit 57 travels through nearly the same space as the emitted beam.
[0050] FIG. 13 illustrates a problem with prior art sensor unit 57 , a false detection due to the presence of the door 56 and the position of the sensor unit 57 . The emitted beam 58 is reflected by the door 56 and can cause the sensor unit 57 to provide a false indication of a user being presence or, if calibrated to account for the strong reflection from the door 56 , can be too insensitive to detect the relatively weaker reflection from a user.
[0051] In one embodiment, the actuator assembly 100 includes the sensor unit 300 . The sensor unit 300 may be in communication with other components of the actuator assembly 100 so as to enable automatic actuation of the flush valve upon the detection of a certain state, such as the presence and then absence of a user. One implementation of the sensor unit 300 , an embodiment of which is illustrated in FIG. 4A , comprises an active sensor having an emitter 310 and a sensor receiver 320 . The emitter 310 of the embodiment in FIG. 4A includes a first emitter 311 and a second emitter 312 .
[0052] One embodiment, examples of which are illustrated in FIGS. 12A-D , the emitters 311 , 312 are positioned at an angle with respect to the actuator assembly 100 and valve body 10 , in one implementation at a compound angle of 2-15 degrees, preferably 5-11 degrees and more preferably 5-7 degrees in an alternative embodiment, most preferably 10 degrees from perpendicular to the normal line of the sensor unit 300 in the horizontal and 6-30 degrees, preferably 12-20 degrees, more preferably 12-15 degrees, and most preferably 15 degrees from perpendicular in the vertical. It should be understood that the position of the emitters 311 , 312 is described with respect to their emitted beams rather than the physical emitter. The two emitters 311 , 312 may be positioned such that their beams are angled in the opposite direction in the horizontal, the vertical, or both. The sensor receiver 320 is angled, 5-11 degrees from perpendicular in the horizontal. Thus, each of the emitters 311 , 312 is at a non-transverse angle with respect to the handle axis. FIGS. 12A-D illustrate various views of the field of emission for one embodiment of the sensor unit 300 . As can be seen in FIGS. 12A-D , the position of the emitters 311 , 312 results in the sensor unit's output being nontransverse with respect to the handle 17 . In one embodiment, the sensor unit 300 is positioned such that the emitters 311 , 312 are angled, in the horizontal, towards a center line of the associated fixture, such as a toilet, to provide an emitter field roughly corresponding to where a user would be positioned at the center of the fixture. In one embodiment, the emitters 311 , 312 beams are non-parallel and non-perpendicular to a vertical longitudinal plane. In one implementation, the emitters 311 , 312 beams are also non-parallel and non-perpendicular with respect to each other, preferably such that they extend at opposite angles from the actuator assembly 100 . In one implementation, the sensor receiver 320 and the at least one emitter 310 are at an angle respect to each other.
[0053] The position of the emitters 311 and 312 being angled with respect to the sensor unit 300 , such as being mounted on angled spacers, and side mount actuator assembly 100 result in the specularly reflected rays from an object such as a door 56 being reflected away from the sensor receiver 320 . FIG. 14A illustrates an embodiment of the sensor unit 300 having an angled emitter with an emitted beam 301 that is angled in the vertical with respect to the valve body 10 . The major reflected rays 370 do not reflect back to the sensor receiver 320 and, thus, significantly reduce the chances of a false indication of a user. FIG. 14B illustrates the sensor unit 300 of FIG. 14A with a user present. The emitted beam 301 is reflected by the user in a much wider field due to the typically non-planar surface of the user and the specular reflecting materials worn by most users. At least a portion of the reflected rays 380 return to the sensor receiver 320 , allowing for a detection of the user's presence.
[0054] FIG. 12E illustrates the non-angled emitted beam in the horizontal that is reflected to the sensor by a top of a lifted toilet seat and causes a false indication of a user. FIGS. 12C and 12D illustrate an embodiment of the sensor unit 300 having an angled emitter with an emitted beam 301 that is angled in the horizontal with respect to the valve body 10 . In the horizontal, the emitters 311 , 312 are angled, towards a center line of the associated fixture 5 , such as a toilet, not only to provide an emitter field roughly corresponding to where a user would be positioned at the center of the fixture, but also significantly to reduce the chances of a false indication of a user by the reflection from the lifted toilet seat because the angled beam passes through the top gap of toilet seat.
[0055] FIG. 12A is a down-looking emitter for higher mounting installations and for short users; FIG. 12B is a side-view of an up-looking emitter for lower mounting installations to avoid the reflection from the toilet bowl and seat.
[0056] FIGS. 3A and 3B illustrate a sensor aperture 360 in the housing 110 . The sensor aperture 360 allows the emitters 311 , 312 to be in communication with the environment outside of the housing 110 , i.e. for the emitted beam 301 to exit the side mount actuator assembly 100 . A sensor aperture cover 361 may be removably positioned in the sensor aperture 360 of the housing 110 to allow the emitted beam to 301 but to prevent tampering and protection from external liquids with the sensor 300 and to provide an aesthetically pleasing look. For example, the aperture cover 361 may be transparent to infrared energy but less transmitting with respect to visible light for red and green indicators. In one embodiment, the PCB support 231 positions the sensor adjacent the sensor aperture 360 . The sensor aperture 360 may be on a forward-facing portion of the housing 110 . The sensor aperture cover 361 may be parallel with the PCB 230 and the portion of the housing 110 in which the sensor aperture cover 361 is positioned, but at an angle with respect to the emitter 310 .
[0057] The sensor unit 300 may also include one or more visual indicators, such as LEDs 320 ( FIG. 15A ). For example, the LEDs 320 may provide a visual indication, through the sensor aperture, of the status or state of the side mount actuator assembly 100 .
[0058] In one embodiment, the a photocell 318 is provided. The photocell 318 is used upon manufacturing shipment, ex-factory, to extend battery life of on board installed batteries. When in packaging and at the initial power up stages of the side mount actuator assembly 100 , the photocell 318 detects darkness and causes the unit to power down and conserve battery power. When the side mount actuator assembly 100 is installed and exposed to visible light, the logic causes the photocell 318 to become nonfunctional and the unit operates as intended throughout its remaining life; even if dark bathrooms are encountered.
[0059] In certain environments, too much ambient light mixing with the I.R. signal causes interference with an I.R. receiver. Interference with the sensor receiver 320 causes to high a noise level for logic to process, causing malfunction and unanticipated detection. The malfunction can manifest itself in not properly detecting valid targets. Much of this interference comes from the lighting fixtures in a restroom. There are two mechanisms in the lighting which causes receiver interference: 1) the ballast frequency which the particular ballast operates at, 2) the ballast intensity, along with the manufacturer of the light tube and the internal coating on the inside of the bulb. Electronic ballasts determine how much energy gets input into the fluorescent light tube. Interferences can also come from light and other sources such as T.V.
[0060] In one embodiment, illustrated in FIGS. 15A-C , a transreflective filter 363 is utilized. This transreflective filter 363 decreases the background noise caused by lighting fixtures, limiting the amount of spectral interference that the sensor receiver 320 detects. In the embodiment of FIGS. 15A-C , the transreflective filter 363 is provided as a layer between the sensor 300 and the aperture cover 361 . The transreflective filter 363 acts as a light filter using graduated lensing, to become sensitive only to certain incident angles. When the transreflective filter is oriented in the proper plane relative to the sensor receiver 320 ; it is a spatial filter fitted over the sensor 300 , for example fitted over only the sensor receiver 320 not the emitters 310 , optimized to maximize the signal detection of the active I.R. emitted by the sensor 300 . The material causes the multiple interfering light sources to be cancelled out while being able to focus on the active I.R. beam reflection angle which is detecting to determine a valid target. More extreme angles of incident confusing light sources (sources that confuse the sensor unit 300 ) are filtered out causing a dramatic increase in system gain which blocks out noise sources as described above.
[0061] In an embodiment illustrated in FIG. 15A , a shroud 365 is provided that receives the emitters 311 , 312 and the shroud 365 gives a partial direction block to the emitter signals. In one implementation, the shroud 365 receives the transreflective filter 336 , which may be keyed to fit within the shroud and be secured by a small frame 364 . The incident light goes through the receiver 320 after passing through the filter 363 . Shroud 365 has blocking passages 366 , 367 for upper and lower target zone detection.
Manual Actuation Assembly
[0062] Although many flush devices are designed with an automatic actuation ability, such as certain embodiments described herein, it is beneficial to provide the ability to manually flush a fixture as well. The handle 17 , such as illustrated in FIG. 1A , cannot be mounted to the valve body 10 if an actuator assembly 100 is attached to the valve body 10 . A manual flush may be accomplished by initiation of the motor 241 without input from the sensor unit or by physical interaction with the plunger, bypassing the motor and gear train assembly 240 . One embodiment of the present invention relates to a manual actuation assembly 400 for manually actuating a flush for a flush valve having an actuator assembly 100 . FIG. 3B , FIGS. 4A-D , FIG. 6A-B , and FIG. 10B best illustrate the manual actuation assembly 400 .
[0063] One embodiment of a manual actuation assembly 400 includes a face plate 428 which serves as a portion of the exterior surface of the mechanism assembly 200 . The manual actuation assembly 400 further includes a mechanical manual actuation assembly 401 . An embodiment of the mechanical manual actuation assembly 400 includes a manual actuation arm 440 that is in communication with a button 411 disposed on the face plate 428 .
[0064] In one embodiment shown in FIG. 4B the arm 440 comprises a first arm 441 and a second arm 442 . The first arm 441 is connected with the button 411 and moves laterally when the button 411 is depressed inward, i.e. it moves in the same general direction as the button 411 . The first arm 441 may be secured to a post 412 attached to the button 411 , such as at a first end 445 of the first arm 441 . The first arm 441 is connected to the second arm 442 , such as pivotally connected at a second end 453 , opposite the first end 445 . In one embodiment, the first arm 441 serves as a linkage between the button 411 and a second arm 442 . The second arm 442 is pivotally connected to the mechanism assembly frame 221 , such as at the two brackets 448 . In one embodiment, the second arm 442 has a generally “H” shape, with two vertical members 443 a , 443 b connecting to the first arm 441 at each of the vertical member first ends 454 a , 454 b and a bracket 448 at the vertical member second ends 446 a , 446 b . The second arm 442 also includes a central stabilizing member 444 connecting the vertical members 443 . In one implementation, the second arm 442 is connected to the mechanism assembly frame 221 at a location below the plane of the first arm 441 , for example at bracket 448 of FIG. 4D , such that movement of the first arm 441 toward the second arm 442 (and, thus, the plunger 800 ) results in the second arm 442 pivoting and arm 440 engaging the plunger 800 to move the plunger 800 to engage the valve stem 32 , initiating a manual flush cycle. In one embodiment, a biasing mechanism 449 , such as a torsion spring, may be used to bias the arm 440 away from the plunger 36 , such that engagement of the button 411 is necessary to move the arm 440 to engage the plunger and release of the button 411 results in the biasing mechanism 449 returning the arm 440 to a resting state not so as not to engage the plunger 800 .
[0065] In one embodiment, the central member 444 of the second arm 442 engages secondary plunger head, such as a protrusion 819 extending from the plunger head 810 . One illustration of a plunger 800 in accordance with this embodiment is shown in FIGS. 8A-B . The protrusion 819 extends from the plunger head 810 and provides a surface for the arm 440 to engage. In one implementation, the central member 444 includes a protrusion or cam 439 for engaging the plunger head protrusion 819 . For embodiments utilizing an automated actuation assembly 220 such as having rollers 510 for engaging the lower portion 811 or the upper portion 812 of the plunger head 810 , the protrusion is positioned apart from but adjacent the portion of the plunger 800 that rollers 510 engage, allowing both the rollers 510 and the arm 440 to be capable of engaging the plunger 800 to effectuate an appropriate flush cycle.
[0066] Where the actuator assembly 100 is a dual flush actuator using a bushing such as illustrated in FIGS. 9A and 9B , the protrusion 819 extends to the side of the plunger head 810 . A plunger head 810 as described above and shown in FIGS. 8A and 8B may be utilized with the dual mode bushing 66 shown in FIGS. 9A and 9B . When the arm 440 engages the plunger head 810 , the plunger 800 travels along the lateral travel path, i.e. the plunger is not titled, resulting in the higher volume flush. It should be appreciated that where the dual mode bushing 66 is such that a lateral travel path is a reduced flush (i.e. it causes the plunger 800 to strike the valve stem 32 at a lower point than a tilted travel path), the engagement of the protrusion 819 will result in a reduced flush.
[0067] In one embodiment, such as illustrated in FIGS. 4D and 10B , a user presses the button 411 , which moves the first arm 441 substantially laterally, engaging the second arm at a first end and pivoting the second arm about a pivot point at the bracket connecting a second end of the arm to the frame 221 , such that the central stabilizing member 444 of the second arm 442 engages the protrusion 819 of the plunger 800 .
[0068] FIG. 6A illustrates an embodiment of the face plate 428 having an outer cover 450 and an inner face plate frame 460 . The outer cover 450 includes a button opening 452 and a outer cover battery opening 451 . The inner face plate frame 460 includes a inner face plate frame battery opening 461 and a button frame 462 which supports a button 411 that extends through the button opening 452 . The button 411 may include a peripheral portion 419 secured between the outer cover 450 and inner face plate frame 460 . Outer cover openings 457 correspond to inner face plate frame openings 467 to receive the fastener 190 (illustrated as an embodiment having two fasteners and corresponding openings 457 , 467 ) to secure the mechanism assembly 200 the housing 110 . In one embodiment, battery fastener outer cover openings 456 correspond to battery fastener inner face plate frame openings 466 to receive the fastener 195 to secure the battery assembly 700 to the mechanism assembly 200 , with the battery assembly 700 being inserted through the battery openings 451 , 461 . The button 411 may include a post 412 for engaging the plunger 800 via mechanical interaction, such as through the use of arm 440 .
[0069] In one embodiment, the manual actuation assembly 400 includes, either alone or in combination with the mechanical manual actuation assembly 401 , a manually initiated motorized actuation assembly 402 , such as the embodiment illustrated in FIG. 6B . Thus, manual actuation can be accomplished, in various embodiments, through a mechanical actuation of the plunger, i.e. bypassing the motor 241 , or through a manual actuation of the motor 241 , i.e. without use of the sensor unit 300 . In addition to a button 411 for engaging the plunger 36 through mechanical interaction, a second button 430 may be provided to manually initiate the motor and gear train assembly 240 to start a flush cycle (a reduced or full flush, depending on the structure). The second button 430 may be similarly disposed in the button opening 452 of the outer cover 450 and have a corresponding second button post 431 and supported by a portion of the frame 462 and peripheral portion 419 . The buttons 411 , 430 may utilize a return spring 433 ( FIG. 6B ).
[0070] In one implementation, the second button 430 includes a magnet 432 ( FIG. 6B ) at an end of the second button post 431 . The magnet is positioned to interact with a Hall Effect sensor 235 (shown in FIG. 4A ) positioned on the PCB 230 when the second button 430 is depressed. The electronic components can be programmed in various ways to respond to the Hall Effect sensor 235 , for example it may actuate the motor in one direction so the rollers rotate in a first rotation corresponding with a reduced flush or a second motor direction causing the rollers to rotate in a second rotation corresponding to a full flush. Thus, the second button 430 provides a mechanism, other than the sensor unit 300 , for initiating the motor 241 and the rollers 510 , including the possibility of a reduced flush, while the first button 411 provides a mechanical linkage mechanism for by-passing the motor and gear train assembly 240 to directly interact with the plunger 800 via the arm 440 to initiate a flush, such as a full flush. In one embodiment, the button 411 effectuates a flush for one flush volume of a dual mode flush valve and the second button 430 effectuates a flush for a second flush volume, such as a reduced flush volume, of a dual mode flush valve. It should be appreciated that the mechanical manual actuation assembly 401 and the manually initiated motorized actuation assembly 402 may both initiate the same flush volume, whether a regular flush or a reduced flush, or one may initiate a reduced flush and the other a standard volume flush.
Dual Mode Flush Valves
[0071] One group of flush valves are dual mode flush valves, i.e. flush valves that provide the ability to deliver two discrete flush volumes, typically one sufficient for solid waste evacuation and a lesser flush volume still sufficient for liquid and light paper waste evacuation. One mechanism for providing different flush volumes is to alter the height at which the plunger 36 / 800 contacts the gland 34 . A higher point of contact will result in a longer time for the auxiliary valve 30 to clear the plunger 36 / 800 . The auxiliary valve 30 will remain open until it has cleared the plunger 36 / 800 . In particular, one type of dual mode flush valve is taught by U.S. Pat. No. 7,607,635, which utilizes a dual mode bushing 66 providing two different plunger travel axes that each contact the valve stem 32 at a different vertical location.
[0072] As illustrated in FIGS. 9A and 9B , the bushing 65 may be a dual mode bushing 66 , such as that of the '635 patent, may be utilized for enabling dual flush modes. As previously described, the dual mode bushing 66 is typically disposed or partially disposed within the handle opening 15 . Certain implementations may utilize a general bushing 65 , while dual flush embodiments described herein may utilize a dual mode bushing 66 . The dual mode bushing 66 includes a bushing plunger passage 67 adapted to receive the plunger 36 and for guiding the plunger to the gland 34 . The dual mode bushing 66 also serves to prevent water from exiting the valve body 10 though the handle opening 15 . FIG. 2 illustrates a gasket 80 that may be used to provide a water-tight seal between the dual mode bushing 66 and the valve body 10 . A plunger gasket 81 provides a water-tight seal at the end of the bushing passage adjacent the valve stem 32 ( FIG. 1B ).
[0073] The dual mode bushing 66 allows the plunger to tilt within the dual mode bushing 66 such that the plunger 36 will strike the gland 34 at different vertical heights. In one embodiment, the dual mode bushing 66 has an enlarged opening adjacent the valve stem and includes two paths “A” and “B” of plunger travel, which allow the plunger 36 to strike the valve stem 32 at two different vertical locations depending on the path of travel. As explained in the '635 patent, the vertical location on the gland 34 that the plunger 36 strikes impacts the flush volume, with a high strike point being correlated with larger flush volumes. As set forth in the '635 patent, the tilting of the handle 17 allows for engagement of a peripheral portion of the plunger head resulting in a moment. In the dual mode bushing 66 , an enlarged portion of the bushing plunger passage 67 allows the plunger 36 to tilt, when aligned vertically to lay in the vertical plane, depending where the peripheral portion of the plunger head 37 is engaged. It will be understood that the bushing plunger passage 67 will not allow the plunger to tilt in any direction, but only when actuated in line with the enlarged portion to allow tilting. In one embodiment, the dual mode bushing 66 includes an outer skirt 70 and a bushing central sleeve 68 , connected via a wall 72 . The central sleeve 68 further defines the bushing plunger passage 67 of the dual mode bushing 66 for receiving the plunger 36 . The plunger 36 described above moves laterally through the dual mode bushing 66 to contact the valve stem 32 . The mechanism of actuating the flush valve 1 must provide a motive force to move the plunger 36 .
[0074] In one embodiment, the present invention relates to a side mount actuator assembly 100 for selectively engaging a plunger 36 guided by the dual mode bushing 66 to effectuate one of two flush modes: a high volume sufficient for solid waste or a lower volume for conserving water, but sufficient for liquid and light paper waste, such as a 30% reduction from a “standard” flush (higher relative volume). The actuator assembly 100 engages the plunger 800 to move along either the first plunger travel path “A” or the second plunger travel path “B” to effectuate the desired flush volume. The actuator assembly 100 may be utilized in place of a manual handle 17 .
[0075] With respect to FIGS. 8A and 8B , one implementation of a plunger 800 is illustrated for use with a manual actuation assembly 400 . It should be appreciated that a plunger 36 may be used with various implementations and that plunger 800 may be used with, for example, the described embodiments having the manual actuation assembly 400 . The plunger 800 comprises a plunger head 810 and a plunger shank 820 connected thereto. The plunger head 810 is positioned at a first (outer, with respect to the valve body 10 ) end 802 of the plunger 800 . The plunger shank 820 extends from the plunger head 810 to the second (inner, with respect to the valve body 10 ) end 803 of the plunger 800 , adjacent the valve stem 32 . At a first side opposite the plunger shank 820 , the plunger head 810 tapers from a center to the perimeter. The plunger head 810 includes a lower portion 811 and an upper portion 812 In one embodiment, the plunger head 810 at least two angled surfaces, corresponding to lower portion 811 and upper portion 812 , respectfully, that provide a follower surface for interaction with the automated actuation assembly 220 as further described below. In one embodiment, the lower portion and upper portion are not in the same plane, with the lower portion 811 and upper portion 812 each comprising one or more faces of a polyhedron. In an alternative implementation, the plunger head comprises a curved surface, such as forming a frustum, semi-ellipsoid, semi-paraboloid, semi-spheroid or semisphere, with the lower portion 811 and the upper portion 812 each corresponding to an opposite portion of the curved surface.
[0076] The automated actuation assembly 220 for use with a dual flush mode flush device is best illustrated in FIGS. 4A-D . In addition to the components described above, one embodiment of the automated actuation assembly 220 includes as part of the gear train 242 a roller system 500 . Rotation of the motor 241 , such as a traditional small electric motor spinning a drive shaft, rotates a gear 243 in the gear train 242 . Rotation of the gear train 242 engages the plunger 800 .
[0077] In one embodiment, illustrated in FIG. 5B , one or more rollers 510 are positioned on a rotating platform, such as a roller support gear 501 . One or more rollers 510 are connected to the roller support gear 501 , wherein the one or more rollers 510 are spaced from the center of the roller support gear 501 such that the one or more rollers 510 travel a path about the center when the roller support gear 501 is rotated. The one or more rollers 510 are configured to engage the plunger head 810 as a cam. For example, as illustrated in FIG. 11 , the rollers 510 may be positioned to rotate generally in the vertical plane such the that plunger is engaged with an upward curving rotation or a downward curving rotation of the rollers 510 . In one implementation, the one or more rollers 510 are rotatable in a clockwise or counterclockwise direction. For example, when the motor 241 is run “forward” the one or more rollers 510 rotate in one direction and when the motor 241 is run in “reverse” the one or more rollers 510 rotate in the opposite direction. In one implementation, rotation in a clockwise direction results in at least one of the rollers 510 engaging the lower portion 811 of the plunger 800 and rotation in a counterclockwise direction results in at least one of the rollers 510 engaging the upper portion 812 of the plunger 800 . FIG. 11 and FIG. 10C best illustrate the spatial arrangement of the components, including the positioning of the rollers 510 relative to the plunger head 810 .
[0078] In one embodiment program logic is utilized to control the motor. For side mount actuator assemblies having dual mode flush capabilities, such as utilizing a dual mode bushing 66 , the program logic, in one embodiment, utilizes input from the sensor unit 300 and applies logical instructions, such as computer program code, to determine if a reduced flush or a normal volume flush should be utilized. For example, where rotation of the motor in a clockwise direction achieves a reduced flush, the program logic will initiate a clockwise rotation of the motor when the sensor unit indicates only a short direction presence indicative of a liquid waste event. In contrast, upon detection of a longer presence, the program logic initiates rotation of the motor in a counter clockwise direction to effectuate a normal flush as the sensor unit's input is indicative of a solid waste event.
[0079] It should be appreciated that the actuator assembly 100 may be mounted in a “left hand” or “right hand” position with respect to the valve body 10 . A single actuator assembly 100 may be useable in either position by allowing an installer to select the orientation of installation. The actuator assembly 100 is right-side up in one orientation and upside down, respectively, in the other. Therefore, in one implementation, the direction of rotation of the motor 241 , and thus the one or more rollers 510 , associated with a particular flush volume is reversed between the left-handed installation and the right-handed installation. A switch (not shown) may be provided on the PCB 230 to accomplish the change in relationship between the motor rotation and the flush volume. A tilt sensor (not shown) may be provided on the PCB 230 to provide an indication of orientation of the actuator assembly 100 , and thus the type of installation, i.e. left hand or right hand, where the actuator assembly 100 is right-side up for one of a left hand or right hand installation and upside down in the other installation. In one embodiment, the dual mode bushing 66 is keyed to match the receptacle 120 as described previously and the keying is such to accommodate either a left-hand or right-hand position. In one embodiment, the bushing 65 (including if a dual mode bushing 66 is utilized) is a separate and distinct component from the side mount actuator assembly 100 . Thus, the bushing 65 may be rotated separately for a left-hand or right-hand installation as necessary, particularly if a dual mode bushing 66 is utilized to ensure proper location of the dual mode bushing 66 for achieving a reduced flush.
[0080] In one embodiment illustrated in FIGS. 5A and 5B , the one or more rollers 510 are connected to the roller support gear 501 by pins 511 that engage gear pin holes 521 and pin holes 513 in a top plate 512 that is secured to the roller support gear 501 such as by protrusion 522 that mates with an opening 514 in the top plate 512 . A support shaft 530 may pass through the top plate opening 514 and an protrusion opening 523 to support the roller system 500 .
[0081] The use of the dual mode bushing 66 allows the plunger 800 to tilt where the action of the rollers 510 or manual action (discussed below) creates a sufficient moment with a specific vector to tilt the plunger 800 in the dual mode bushing 66 . The plunger 36 is aligned within the dual mode bushing 66 such that the upper portion 812 corresponds with the top of the dual mode bushing 66 , which has an angled portion to allow the plunger 800 to tilt the end adjacent the valve stem 32 downward. This downward tilt of the plunger end results in a lower flush volume as described in U.S. Pat. No. 7,607,635. Rotation of the rollers 510 in a first direction, engaging the upper portion 812 , results in lateral movement of the plunger to engage the flush valve stem at a first location and a “normal” flush volume sufficient for solid waste. Rotation of the rollers 510 in a second direction, engaging the lower portion 811 , results in a tilting of the plunger 800 and lateral movement of the plunger 800 to engage the flush valve stem 32 at a location below the first location effectuating a “reduced” flush volume that remains sufficient for liquid—but not intended for solid waste. The reduction may be from a normal flush volume of about 1.6 gpf to a reduced 1.3 gbf. In one embodiment, the reduction may be 30% from a “normal” flush.
Battery Tray
[0082] In one embodiment portable energy sources are utilized, such as batteries 701 . A battery assembly 700 may be provided. The battery assembly 700 may be as shown in FIG. 7 . The battery assembly 700 is configured to be disposed within the housing 110 .
[0083] In one embodiment, the battery assembly 700 includes batteries 701 insertable into a tray 710 having at one end a first linked pair of electrodes 704 wherein one of the pair is a positive electrode (e.g., 704 a ) and the other a negative (e.g., negative electrode 704 b ) and at a second, opposite, end a set of unlinked electrodes 705 , 706 (such as a positive electrode 705 opposite negative electrode 704 b and a negative electrode 706 opposite positive electrode 704 a ). Each electrode 704 a , 704 b , 705 , 706 is conductively connected to the support plate 280 . The blade electrodes 781 , 782 are configured to receive a corresponding blade 281 , 282 , respectively. The blades 281 , 282 are connected to the mechanism assembly frame 221 . The assembly frame 221 is in conductive communication with the PCB 230 to provide electricity to the electrical components.
[0084] A spring contact 740 may be provided in one embodiment within the housing 110 to assist in removal of the battery assembly 700 . In one embodiment, the battery assembly 700 includes a battery assembly cover 720 covering outer cover openings 456 and fasteners 195 to provide a more aesthetic look and to hinder tampering with the actuator assembly 100 . The battery assembly 700 may be affixed to the mechanism assembly 200 by a battery assembly fastener 195 , such as a screw, that engages a battery assembly hole 795 in the cover 720 and the battery fastener outer cover opening 456 in the face plate 428 .
[0085] One embodiment of the invention relates to a complete flushometer valve assembly, such as either a diaphragm valve or a piston valve, with the bushing being a dual flush mode bushing and the actuator assembly being a side mount automatic actuator, such as for new construction installation. An alternative embodiment comprises only the actuator assembly, such as for converting existing installed dual mode valve bodies to automatic flush systems. Alternatively, one embodiment relates to the actuator assembly and a dual flush mode bushing, such as for converting existing single mode flush valves to automatic dual mode flush valves.
[0086] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any inventions or of what may be claimed, but rather as descriptions of features specific to particular implementations of particular inventions. Certain features described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable sub combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub combination or variation of a sub combination. Furthermore, headings are provided as a visual aid and should not be construed to limit the scope of the invention.
[0087] It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated”, “coupled” or “connected” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components.
[0088] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
[0089] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least”). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include, but not be limited to, systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
[0090] Thus, particular implementations of the invention have been described. Other implementations are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. | A flush actuator for engaging a flush valve. The flush actuator provides a mechanism assembly for automatically flushing the flush valve. A sensor provides a presence detection to trigger the automatic flushing. Redundant manual activation is provided. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to a system and method for delivering and regulating process gas streams to fuel cell stacks.
BACKGROUND OF THE INVENTION
[0002] A fuel cell is an electrochemical device that produces an electromotive force by bringing the fuel (typically hydrogen) and an oxidant (typically air) into contact with two suitable electrodes and an electrolyte. A fuel, such as hydrogen gas, for example, is introduced at a first electrode where it reacts electrochemically in the presence of the electrolyte to produce electrons and cations in the first electrode. The electrons are circulated from the first electrode to a second electrode through an electrical circuit connected between the electrodes. Cations pass through the electrolyte to the second electrode. Simultaneously, an oxidant, such as oxygen or air is introduced to the second electrode where the oxidant reacts electrochemically in presence of the electrolyte and catalyst, producing anions and consuming the electrons circulated through the electrical circuit; the cations are consumed at the second electrode. The anions formed at the second electrode or cathode react with the cations to form a reaction product. The first electrode or anode may alternatively be referred to as a fuel or oxidizing electrode, and the second electrode may alternatively be referred to as an oxidant or reducing electrode. The half-cell reactions at the two electrodes are, respectively, as follows:
H2→2H++2 e− ½O 2 +2H++2 e−→H 2 O
[0003] The external electrical circuit withdraws electrical current and thus receives electrical power from the cell. The overall fuel cell reaction produces electrical energy as shown by the sum of the separate half-cell reactions written above. Water and heat are typical by-products of the reaction.
[0004] In practice, fuel cells are not operated as single units. Rather, fuel cells are connected in series, stacked one on top of the other, or placed side by side. A series of fuel cells, referred to as fuel cell stack, is normally enclosed in a housing. The fuel and oxidant are directed through manifolds to the electrodes, while cooling is provided either by the reactants or by a cooling medium. Also within the stack are current collectors, cell-to-cell seals and insulation, with required piping and instrumentation provided externally of the fuel cell stack. The stack, housing, and associated hardware make up the fuel cell module.
[0005] The optimal operating level of components of the fuel cell system will depend upon the particular system operating level of the entire fuel cell system. Thus, for example, the optimal operating level of a blower for providing a process fluid to the fuel cell system will depend upon the particular system operating level of the fuel cell system. As the operating level of the fuel cell system increases, the optimal operating level of the blower will also increase. Analogously, as the operating level of the fuel cell decreases, the optimal operating level of the blower will decrease. In prior art systems, feedback from process parameters, such as cathode airflow, various temperatures and fuel cell voltages, are monitored and are used to either increase or decrease the operating level of individual components of the fuel cell system based upon the needs of the fuel cell system.
SUMMARY OF THE INVENTION
[0006] In accordance with an aspect of the present invention, there is provided a method of operating a fuel cell system. The method comprises (a) operating a component of the fuel cell system at a component operating rate; (b) driving a load using the fuel cell; (c) measuring an operating rate of the fuel cell; (d) normally adjusting the component operating rate in dependence upon the operating rate of the fuel cell; and, (e) in response to selected changes in the operating rate of the fuel cell, indicative of corresponding changes in the demand from the load, delaying adjustment of the component operating rate.
[0007] In accordance with a second aspect of the present invention, there is provided a fuel cell system comprising (a) a fuel cell for driving a load; (b) at least one measuring device for monitoring an operating rate of the fuel cell; (c) a controller for controlling an operation rate of a component of the fuel cell system based on the operating rate of the fuel cell; and, (d) means for detecting selected changes in the operating rate of the fuel cell, indicative of corresponding changes in the demand from the load, and in response thereto, delaying adjustment of the operation rate of the component.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] For a better understanding of the present invention and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings which show an embodiment of the present invention and in which;
[0009] [0009]FIG. 1 is a schematic flow diagram of a first embodiment of a fuel cell gas and water management system in accordance with an aspect of the present invention; and,
[0010] [0010]FIG. 2 is a block diagram of a controller for use in connection with the fuel cell gas and water management system of FIG. 1 in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0011] For delivering and regulating process fluids, for example air and hydrogen gas streams, to a fuel cell stack, it is important to provide the process fluids in a required amount at a precise time. The following description will use as an example the delivery and regulation of air to a cathode portion of a fuel cell stack 12 . The same general principles can also be applied to other fluid deliveries, for example the hydrogen gas stream to the fuel cell stack.
[0012] Referring to FIG. 1, this shows a schematic flow diagram of a fuel cell gas management system 10 in accordance with an aspect of the present invention. The fuel cell gas management system comprises a fuel supply line 20 , an oxidant supply line 30 , a cathode exhaust recirculation line 40 and an anode exhaust recirculation line 60 , all connected to the fuel cell 12 . It is to be understood that the fuel cell may comprise a plurality of fuel cells (a fuel cell stack) or just a single fuel cell. For simplicity, the fuel cell 12 described herein operates on hydrogen as fuel and air as oxidant and can be a Proton Exchange Membrane (PEM) fuel cell. However, the present invention is not limited to this type of fuel cells and is applicable to other types of fuel cells that rely on other fuels and oxidants.
[0013] The fuel supply line 20 is connected to a fuel source 21 for supplying hydrogen to the anode of the fuel cell 12 . A hydrogen humidifier 90 is disposed in the fuel supply line 20 upstream from the fuel cell 12 and an anode water separator 95 is disposed between the hydrogen humidifier 90 and the fuel cell 12 . The oxidant supply line 30 is connected to an oxidant source 31 , e.g. ambient air, for supplying air to the cathode of the fuel cell 12 . An enthalpy wheel 80 is disposed in the oxidant supply line 30 upstream of the fuel cell 12 and also in the cathode recirculation line 40 . A cathode water separator 85 is disposed between the enthalpy wheel 80 and the fuel cell 12 . The enthalpy wheel 80 comprises porous material with a desiccant. In known manner, a motor 81 drives either the porous materials or a gas diverting element to rotate around the axis of the enthalpy wheel so that gases from the oxidant supply line 30 and the oxidant recirculation line 40 alternately pass through the porous materials of the enthalpy wheel. Dry ambient air enters the oxidant supply line 30 and first passes through an air filter 32 that filters out the impurity particles. A blower 35 is disposed upstream of the enthalpy wheel 80 , to draw air from the air filter 32 and to pass the air through a first region of the enthalpy wheel 80 . The enthalpy wheel 80 may be any commercially available enthalpy wheel suitable for fuel cell system, such as the one described in the applicant's co-pending U.S. patent application Ser. No. 09/941,934.
[0014] A fuel cell cathode exhaust stream contains excess air, product water and water transported from the anode side, the air being nitrogen rich due to consumption of at least part of the oxygen in the fuel cell 12 . The cathode exhaust stream is recirculated through the cathode exhaust recirculation line 40 connected to the cathode outlet of the fuel cell 12 . The humid cathode exhaust stream first passes through the hydrogen humidifier 90 in which the heat and humidity is transferred to incoming dry hydrogen in the fuel supply line 20 . The humidifier 90 can be any suitable humidifier, such as that commercially available from Perma Pure Inc, Toms River, N.J. It may also be a membrane humidifier and other types of humidifier with either high or low saturation efficiency. In view of the gases in the anode and cathode streams, an enthalpy wheel or other device permitting significant heat and humidity interchange between the two streams cannot be used.
[0015] From the hydrogen humidifier 90 , the fuel cell cathode exhaust stream continues to flow along the recirculation line 40 and passes through a second region of the enthalpy wheel 80 , as mentioned above. As the humid cathode exhaust passes through the second region of the enthalpy wheel 80 , the heat and moisture is retained in the porous paper or fiber material of the enthalpy wheel 80 and transferred to the incoming dry air stream passing through the first region of the enthalpy wheel 80 in the oxidant supply line 30 , as the porous materials or the gas diverting element of the enthalpy wheel 80 rotate around its axis. Then the cathode exhaust stream continues to flow along the recirculation line 40 to an exhaust oxidant water separator 100 in which the excess water, again in liquid form, that has not been transferred to the incoming hydrogen and air streams is separated from the exhaust stream. Then the exhaust stream is discharged to the environment along a discharge line 50 .
[0016] A drain line 42 may optionally be provided in the recirculation line 40 adjacent the cathode outlet of the fuel cell to drain out any liquid water remaining or condensed out. The drain line 42 may be suitably sized so that gas bubbles in the drain line actually retain the water in the drain line and automatically drain water on a substantially regular basis, thereby avoiding the need of a drain valve that is commonly used in the field to drain water out of gas stream. Such a drain line can be used anywhere in the system where liquid water needs to be drained out from gas streams. Pressure typically increases with gas flow rate and water regularly produced or condensed, and a small flow rate of gas is not detrimental such as cathode exhaust water knockout separator and drain line 42 .
[0017] The humidified hydrogen from the hydrogen humidifier 90 flows along the fuel supply line 20 to the anode water separator 95 in which excess water is separated before the hydrogen enters the fuel cell 12 . Likewise, the humidified air from the enthalpy wheel 80 flows along the oxidant supply line 30 to the cathode water separator in which excess liquid water is separated before the air enters the fuel cell 12 .
[0018] Fuel cell anode exhaust comprising excess hydrogen and water is recirculated by a pump 64 along an anode recirculation line 60 connected to the anode outlet of the fuel cell 12 . The anode recirculation line 60 connects to the fuel supply line 20 at a joint 62 upstream from the anode water separator 95 . The recirculation of the excess hydrogen together with water vapor not only permits utilization of hydrogen to the greatest possible extent and prevents liquid water from blocking hydrogen reactant delivery to the reactant sites, but also achieves self-humidification of the fuel stream since the water vapor from the recirculated hydrogen humidifies the incoming hydrogen from the hydrogen humidifier 90 . This is highly desirable since this arrangement offers more flexibility in the choice of hydrogen humidifier 90 as the humidifier 90 does not then need to be a highly efficient one in the present system. By appropriately selecting the hydrogen recirculation flow rate, the required efficiency of the hydrogen humidifier 90 can be minimized. For example, supposing the fuel cell 12 needs 1 unit of hydrogen, hydrogen can be supplied from the hydrogen source in the amount of 3 units with 2 units of excess hydrogen recirculated together with water vapor. The speed of pump 64 may be varied to adjust the portion of recirculated hydrogen in the mixture of hydrogen downstream from joint 62 . The selection of stoichiometry and pump 64 speed may eventually lead to the omission of the hydrogen humidifier 90 .
[0019] In practice, since air is used as oxidant, it has been found that nitrogen crossover from the cathode side of the fuel cell to the anode side can occur, e.g. through the membrane of a PEM fuel cell. Therefore, the anode exhaust actually may contain some nitrogen and possibly other impurities. Recirculation of anode exhaust may result in the build-up of nitrogen and poison the full cell. Preferably, a hydrogen purge line 70 branches out from the fuel recirculation line 60 from a joint or connection 74 adjacent the fuel cell cathode outlet. A purge control device 72 is disposed in the hydrogen purge line 70 to purge a portion of the anode exhaust out of the recirculation line 60 . The frequency and flow rate of the purge operation is dependent on the power at which the fuel cell 12 is running. When the fuel cell 12 is running at high power, it is desirable to purge a higher portion of anode exhaust. The purge control device 72 may be a solenoid valve or other suitable device.
[0020] The hydrogen purge line 70 runs from the position 74 to a joint or connection 92 at which it joins the cathode exhaust recirculation line 40 . Then the mixture of purged hydrogen and the cathode exhaust from the enthalpy wheel 80 passes through the exhaust water separator 100 . Water is condensed in the water separator 100 and the remaining gas mixture is discharged to the environment along the discharge line 50 . Alternatively, either the cathode exhaust recirculation line 40 or the purge line 70 can be connected directly into the water separator 100 .
[0021] Preferably, water separated by the anode water separator 95 , the cathode water separator 85 , and the exhaust water separator 100 is not discharged, but rather the water is recovered, from these separators respectively, along a line 96 , a line 84 and a line 94 to a product water tank (not shown).
[0022] As is known to those skilled in the art, a coolant loop 14 runs through the fuel cell 12 . A pump 13 is disposed in the cooling loop 14 for circulating the coolant. The coolant may be any coolant commonly used in the field, such as any non-conductive water, glycol, etc. An expansion tank 11 can be provided in known manner. A heat exchanger 15 is provided in the cooling loop 14 for cooling the coolant flowing through the fuel cell 12 to maintain the coolant within an appropriate temperature range. FIG. 1 shows one variant, in which a secondary loop 16 includes a pump 17 , to circulate a secondary coolant. A heat exchanger 18 , e.g. a radiator, is provided to maintain the temperature of the coolant in the secondary loop and again, where required, an expansion tank 19 is provided. The coolant in the cooling loop 16 may be any type of coolant as the coolants in cooling loop 14 and 16 do not mix. However, it is to be understood that the second cooling loop is not essential.
[0023] In the invention, as exemplified for the cathode air delivery, a time delay is introduced when a demand for spooling down blower 35 is generated during operation of the fuel cell system. When demand from a load 200 connected to the fuel cell 12 drops off, i.e. the current draw requirements, measured by amperemeter 250 (FIG. 2) go down, the flow of air is held high for a certain pre-set time (for example 10 seconds) at the earlier higher load conditions. This is done so that the fuel cell system 10 can quickly be responsive to any immediate load increase demand shortly after the load demand has decreased. A situation like this might arise when the fuel cell system is powering a moving vehicle and the driver has ceased accelerating, but immediately after slowing down again presses an accelerator pedal, or uses some other means, to increase speed again.
[0024] A controller 300 of the system 10 of FIG. 1 is shown in FIG. 2, and compares the previous load level with the current load level, and holds the system air throughput at this level (corresponding to the previous load and operating level of the fuel cell system). The load changes that fall into this category of “abrupt” load changes are changes that occur at at least a pre-determined rate: thus “substantial” changes over “short” periods of time. The actual definition of change rate, “substantial” and “short” will depend on the application the fuel cell system is used in.
[0025] By using a system according to the invention near instantaneous transient power output back to a previous load level is possible. In practical use, one transient in power demand (load current draw) may often be followed by another transient in power demand in the opposite direction. Transient power demand is typical for city driving conditions for a vehicle as mentioned earlier, for instance in stop-and-go traffic. In such a situation, a transient reduction in a power demand, resulting from a vehicle stopping or slowing down at a stoplight or due to traffic, may be followed very shortly by a transient increase in power as the way ahead clears for the vehicle and the driver applies more pressure to the accelerator. If the blower is operating at a low rate due to the prior reduction in load, the fuel cell system will be less able to quickly increase power output to meet increased demand. Thus, the controller controls the operation of the fuel cell system in a way that anticipates flow demands that may arise from probable fuel cell system user behavior.
[0026] Referring to FIG. 2, the controller 300 is illustrated in a block diagram. The controller 300 includes a storage module 302 for storing a selected time lag and a selected rate of decrease in the load. Both the selected time lag and the selected rate of decrease in the load are selected based on the particular application of the fuel cell system, and may be subsequently modified to improve performance. A linkage module 306 of controller 300 is linked to amperemeter 250 , thereby enabling the controller 300 to monitor the load 200 placed on the fuel cell system 10 . As demand from the load 200 diminishes, the rate of decrease in the demand is communicated from the amperemeter 250 to the linkage module 306 , and from the linkage module 306 to a processor or logic module 308 . The processor or logic module 308 then determines whether the actual rate of decrease in the load 200 exceeds the threshold rate of decrease stored in the storage module 302 . If the rate of decrease in the load 200 does not exceed the threshold rate of decrease stored in the storage module 302 then the logic module 308 via linkage 306 will reduce the operating level of the blower 35 to correspond to the lower operating level of the fuel cell system 10 needed for load 200 . If, however, the rate of decrease in the load 200 exceeds the threshold rate of decrease stored in the storage module 302 , then the logic module 308 will delay reducing the operating level of the blower 35 by a period of time equal to the time lag stored in the storage module 302 . After this time lag, the logic module 308 will lower the operating level of the blower 35 to correspond to the lower operating level of the fuel cell system 10 needed for load 200 .
[0027] Other variations and modifications of the invention are possible. For example, instead of, or in addition to, the operating rate of the blower 35 being regulated, the operating rate of the hydrogen recirculation pump 64 , and/or the operating rate of the coolant pump 13 as well as other components may be regulated. All such modifications are variations are believed to be within the sphere and scope of the invention as defined by the claims appended hereto. | A method and apparatus are provided for delivery and regulation of a process fluid to a multi-cell electrochemical device. A controller regulates the process fluid flow, after at least one of the process parameters indicates a drop in load current draw, based on the operating rate of the fuel cell and the rate of decrease in the load. | 7 |
PRIORITY INFORMATION
[0001] This application claims priority from U.S. Provisional Patent Application No. 61/087,269, filed on Aug. 8, 2008.
FIELD OF THE INVENTION
[0002] The field of the invention relates to techniques for tubular expansion and sealing in open hole with attachment techniques to an existing tubular.
BACKGROUND OF THE INVENTION
[0003] Various techniques have been developed to expand liners and attach them to existing casing already in the wellbore. Some of these techniques involve running a liner with a wide bell at the bottom where the expansion equipment is located and then driving the swage up the liner and out the top and along the way setting external seals to the surrounding casing as the swage makes an exit. One such process is shown in U.S. Pat. No. 6,470,966. The extensive list of prior art included in that patent is representative of the state of the art in downhole tubular expansion techniques that include attachment to an existing tubular. Other patents show the use of swages that include a series of retractable rollers that can be radially extended downhole to initiate a tubular expansion such as of a casing patch as for example is illustrated in U.S. Pat. No. 6,668,930. Some devices swage in a top to bottom direction as illustrated in U.S. Pat. No. 6,705,395.
[0004] What is needed and addressed by the present invention are refinements to the previous techniques that improve performance, mitigate risk and save time to reduce the cost to the operator. Techniques involving expansion in stages coupled with cementing in between are envisioned. An adjustable swage to expand on location removes the need for oversized bells to house the expansion equipment as done in some techniques. Techniques using cement or just sealing externally in open hole are envisioned. Composite materials facilitate subsequent drill out while improved shoe configuration improves circulation when tripping into the hole. The shoe and/or liner can be rotationally locked to work the string for delivery downhole. These and other advantages will become more apparent to one skilled in the art from a review of the description of the preferred embodiments and the associated drawings, while recognizing that the full scope of the invention is given by the claims.
SUMMARY OF THE INVENTION
[0005] An expansion and cementing assembly is run into the well as the expandable liner is made up. A work string is tagged into the expansion assembly and run to depth. Pressure drives the swage to initially expand and move uphole with the attached work string until the liner is expanded above the location of the subsequent cement placement. The assembly is then lowered to engage the guide/float shoe to perform the cementing step. The swage assembly is then released from the guide/float shoe and the balance of the expansion is performed without further expansion against the recently placed cement. The expansion assembly can start at the guide/float shoe or higher, in which case expansion can occur initially in a downhole direction and later be completed in an uphole direction. Variations without cementing are also contemplated.
BREIF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a view of a wellbore that has been cased with an open hole segment below;
[0007] FIG. 2 is the view of FIG. 1 showing a liner with a float shoe inserted into the open hole segment through the casing;
[0008] FIG. 3 is the view of FIG. 2 with the swage assembly being run in;
[0009] FIG. 4 is the view of FIG. 3 with the circulation established through the swage assembly and the float shoe as the liner is run in;
[0010] FIG. 5 is the view of FIG. 4 with the swage assembly expanded but not yet driven;
[0011] FIG. 6 is the view of FIG. 5 with the swage assembly released from the supporting string and being driven down to the float shoe;
[0012] FIG. 7 is the view of FIG. 6 with the circulation re-established after the swage assembly engages the float shoe;
[0013] FIG. 8 is the view of FIG. 7 with the support string releasing the liner and being advanced further into the liner using additional stands added above;
[0014] FIG. 9 is the view of FIG. 8 with the swage assembly again latched to the supporting string and cement pumped through the float shoe to fill the annulus around the already expanded liner;
[0015] FIG. 10 is the view of FIG. 9 with the swage assembly now driven up to complete the expansion of the liner top into the casing;
[0016] FIG. 11 is the view of FIG. 10 with the swage assembly out of the fully expanded liner and the liner hanger to the surrounding casing engaged;
[0017] FIG. 12 is a view similar to FIG. 1 to illustrate an alternative method;
[0018] FIG. 13 is the view of FIG. 12 with the liner in the well showing a swage assembly connected to the float shoe;
[0019] FIG. 14 is the view of FIG. 13 with the work string run in to engage the swage assembly;
[0020] FIG. 15 is the view of FIG. 14 with the circulation established as the liner is run into the open hole;
[0021] FIG. 16 is the view of FIG. 15 with the swage assembly extended in the liner;
[0022] FIG. 17 is the view of FIG. 16 with the swage assembly pressure released from the float shoe and ready to move uphole;
[0023] FIG. 18 is the view of FIG. 17 with the swage assembly driven uphole;
[0024] FIG. 19 is the view of FIG. 18 with the swage assembly again engaged to the float show after initial expansion;
[0025] FIG. 20 is the view of FIG. 19 with the annulus around the expanded portion of the liner being cemented;
[0026] FIG. 21 is the view of FIG. 20 with the swage assembly driven up to complete the expansion above the cemented zone and engage the hanger on the liner to the casing;
[0027] FIG. 22 is the view of FIG. 21 with the swage assembly removed from the liner;
[0028] FIG. 23 is another view of FIG. 1 for an alternative embodiment without cementing the liner;
[0029] FIG. 24 is the view of FIG. 23 with the liner in the hole and suspended from the surface with an open hole packer outside the liner;
[0030] FIG. 25 is the view of FIG. 24 with the string latched into the swage assembly that is supported at the float shoe;
[0031] FIG. 26 is the view of FIG. 25 with the circulation established for running in the liner;
[0032] FIG. 27 is the view of FIG. 26 with the swage assembly expanded;
[0033] FIG. 28 is the view of FIG. 27 with the swage assembly released to move uphole from the float shoe;
[0034] FIG. 29 is the view of FIG. 28 with the liner expanded and the open hole packer set;
[0035] FIG. 30 is the view of FIG. 29 with the swage expanding the hanger on the liner into contact with the casing; and
[0036] FIG. 31 is the view of FIG. 30 with the swage assembly out of the liner and the float shoe ready to be drilled out or retrieved to the surface.
[0037] FIG. 32 shows an open hole that can be under reamed with respect to the cased hole above;
[0038] FIG. 33 shows a liner inserted and expanded to hang off the casing above with options to seal it with cement or external packers or both or neither;
[0039] FIG. 34 shows an under reamed open hole below the already expanded and hung off liner;
[0040] FIG. 35 shows a production string through the expanded liner and hung off the casing where the production string can be cemented or not as needed;
[0041] FIG. 36 shows a casing patch application using expansion;
[0042] FIG. 37 shows an open hole patch using expansion;
[0043] FIG. 38 shows an open hole patch in an under reamed hole;
[0044] FIG. 39 shows an under reamed open hole below a cased hole;
[0045] FIG. 40 is the view of FIG. 39 with a liner inserted and expanded to create a lower bell in the under reamed portion of the well;
[0046] FIG. 41 is the view of FIG. 40 with the shoe drilled out of the bottom of the expanded liner and further showing a variety of sizes of new hole to be drilled deeper;
[0047] FIG. 42 is the view of FIG. 41 with a production string run in and hung off the casing and optionally cemented;
[0048] FIG. 43 is the view of FIG. 41 with a second liner hung off from the bell of the liner above and optionally externally sealed with cement or/and one or more packers pr neither;
[0049] FIG. 44 is the view of FIG. 43 with the lower liner expanded in two dimensions to create a lower bell;
[0050] FIG. 45 is the view of FIG. 44 with the length of the liner below the liner lap expanded to allow for high setting a subsequent liner in the event of a hole collapse;
[0051] FIG. 46 shows a sequence of liners allowing the sidetrack exit while maintaining bore size;
[0052] FIG. 47 shows a cased hole with a bell on the lower end of the casing that can be there for run in or created with expansion of a subsequent liner and an under reamed open hole below;
[0053] FIG. 48 is the view of FIG. 45 with a liner run in and hung off in the casing bell and optionally sealed with cement or/and one or more external packers or neither;
[0054] FIG. 49 shows a casing with a lower bell and an upper liner hung from the bell with an open hole below the size of the expanded liner or under reamed; and
[0055] FIG. 50 is the view of FIG. 47 with a production liner inserted through the expanded liner above it and the production liner hung from above the bell in the casing;
[0056] FIG. 51 shows a cased hole with a bell on the lower end of the casing that can be there for run in or created with expansion of a subsequent liner and an under reamed open hole below.
[0057] FIG. 52 is the view of FIG. 51 with a liner run in and hung off in the casing bell with a second casing bell positioned at the bottom that can be created upon expansion of the liner or created with expansion of a subsequent liner and is optionally sealed with cement and/or one or more external packers or neither.
[0058] FIG. 53 is the view of FIG. 52 with the shoe drilled out and the open hole below under reamed to accommodate a subsequent liner.
[0059] FIG. 54 is the view of FIG. 53 with an additional liner shown run in and hung off as the one above it and as subsequent liners can also be installed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0060] FIG. 1 shows casing 10 in a wellbore 12 that extends from the surface 14 . The open hole portion 16 has a pilot hole 18 at the lower end. A rig 19 is illustrated schematically at the surface 14 . In FIG. 2 a liner 20 is supported from the rig 19 and extends into the open hole 16 . Liner 20 has a hanger/packer 22 on the outside that will eventually support the liner 20 and seal it to the casing 10 . A sealed latch assembly 24 is located inside the float shoe 26 . Float shoe 26 has a spring loaded one way valve 28 as well as a bottom exit 30 as well as side exits 32 . The side exits promote well conditioning during circulation when running in the liner 20 . The float shoe 26 allows flow in the liner 20 to exit but prevents reverse flow such as cement later pumped through the liner 20 and into the surrounding annulus 34 . The float shoe 26 can also be made of a soft composite material or other similar materials that promote rapid drill out after the cementing is completed.
[0061] FIG. 3 shows the insertion of an assembly 36 that comprises from the bottom up a latch component 38 designed to seal and latch to component 24 when brought into contact with it. Further uphole is a piston assembly 40 designed to selectively change the size of the adjustable swage 42 such as is illustrated in U.S. Pat. No. 7,128,146, for example. Further up is an uphole oriented swab cup 44 and a disconnect 46 . A section of pipe 50 spaces the lower swab cup 44 from an oppositely oriented upper swab cup 48 . Further up is a running tool 52 shown gripping the interior of the liner 20 and finally an annular debris barrier 54 is designed to keep debris from getting into the liner 20 as it is circulated when being run into the well 12 .
[0062] FIG. 4 shows a run in string 56 starting to be assembled above the debris barrier 54 and the liner 20 now supported through the string 56 off of rig 19 as it is delivered deeper into the wellbore with circulation through the assembly 36 represented by arrow 58 and return flow represented by arrow 60 . In this view it is easy to see the function of the debris barrier 54 . The valve 28 responds to delivered pressure from the surface 14 to open and let the flow out through the lateral shoe passages 32 to allow for a secondary flow path in case the bottom is plugged when resting on bottom.
[0063] In FIG. 5 a plug or dart or some other obstructing device 62 is dropped or pumped until landed to seal off passage 64 . Then with passage 64 closed at its lower end and pressurized the pressure 66 acts on piston assembly 40 as indicated by arrows 66 . The swage assembly 42 grows in radial dimension to create an initial bump out 68 in the liner 20 .
[0064] In FIG. 6 the pressure in passage 64 has been further increased to cause a separation between components 46 so that the applied pressure in passage 64 now can enter space 70 as indicated by arrows 72 . That pressure acts on lower swab cup 44 that looks uphole while the liner 20 which is gripped by running tool 52 and is supported off of string 56 from rig 19 remains immobile despite uphole pressure on upper swab cup 48 which is downhole oriented. Arrows 66 indicate that pressure on the piston assembly 40 continues to keep the swage assembly 42 at an enlarged dimension as it travels toward the float shoe 26 until components 38 and 24 re-latch and seal as shown in FIG. 7 .
[0065] In FIG. 7 components 38 and 24 have latched and a pressure buildup has popped a disc internal to dart 62 so that circulation can be established with the bulk of the liner 20 below the casing 10 already expanded. Arrows 72 and 74 represent circulation flow through passages 32 and 36 in the float shoe 26 .
[0066] FIG. 8 shows that circulation has stopped and the float shoe 28 is resting on bottom in the pilot hole 18 . The string 56 is being added to at the surface 14 to again bring together the connection 46 so that cementing around the already expanded portion of the liner 20 can take place.
[0067] In FIG. 9 the connection 46 is brought together in a sealing relationship and cement 76 is delivered into annulus 34 to the top 77 of the expanded portion of liner 20 . The cement 76 goes down passage 64 and through the one way valve 28 in the float shoe 26 to the annulus 34 . A wiper plug or dart 78 wipes passage 64 clear of the cement 76 . Optionally some cement 76 can be pumped above plug 78 to ease subsequent drill out as shown in FIG. 10 .
[0068] In FIG. 10 with wiper plug 78 remaining landed a buildup of pressure in passage 64 builds an uphole pressure on sealed latch 24 which has a downhole oriented swab cup 80 whose presence results in an uphole force represented by arrow 82 to drive the assembly 36 uphole to finish the expansion of the liner 20 into a sealed relationship with the casing 10 . The swage assembly 42 remains at maximum dimension because the piston assembly 40 is pressurized at this time as the movement uphole of the 36 continues.
[0069] FIG, 11 shows the expansion of the liner 20 to be complete and the hanger/packer 24 set to the casing 10 as a result of the conclusion of the expansion. It should be noted that the uphole oriented expansion of FIG. 10 does not occur against cement 76 already in annulus 34 . Rather, expansion continues once the extended swage assembly 42 reaches the location 77 which marked the end of expansion. The assembly 36 can now come all the way out of the liner 20 . The shoe 26 can now be drilled out and more hole can be drilled.
[0070] FIG. 12 begins another embodiment for a well with casing 100 and an open hole portion 102 terminating in a pilot hole 104 . In FIG. 13 a liner string 106 is supported from a rig 108 . At the bottom of the liner 106 is a float shoe 110 with a one way valve 112 and lateral exits 114 . The float shoe 110 has a seat 116 for landing a plug as will be later described. A latch assembly 118 releasably holds the swage assembly 120 and the piston assembly 122 that controls the dimension of the swage assembly 120 to the float shoe 110 . Above the piston assembly 122 is one portion 124 of a latch assembly. Outside the liner 106 is a hanger/packer 126 .
[0071] FIG. 14 shows a string 128 with another portion 130 of a connection that will seal and connect to portion 124 . Alternatively, the running string 128 could deliver the piston assembly 122 and the swage assembly 120 with a latch below that engages the float shoe 110 . This engagement can be with a type HRD running tool sold by Baker Oil Tools or an equivalent.
[0072] FIG. 15 shows the liner 106 lowered to the pilot hole 104 and circulation through string 128 out ports 112 and 114 and up through the annulus 133 as represented by arrows 132 and 134 as such lowering is taking place. A debris barrier 136 is at the top of liner 106 for the reason explained before. String 128 supports the liner 106 near its lower end using latch assembly 118 .
[0073] FIG. 16 shows that circulation has stopped and a plug 138 has been landed on seat 116 to allow pressure built up in string 128 to reach the piston assembly 122 so that its movement causes the swage assembly 120 move out to a larger dimension putting a bump out 142 in liner 106 . Further pressure buildup as shown in FIG. 17 releases the latch connection 118 to the float shoe 110 .
[0074] FIG. 18 shows pressure buildup against the plug 138 increasing the volume of chamber 144 as the swage assembly 120 continues to hold its enlarged dimension by virtue of continuous pressure on the piston assembly 122 schematically represented by arrow 140 . The uphole expansion is allowed to continue to a point below the bottom of the casing 100 but leaves the liner 106 expanded over substantially its entire length.
[0075] FIG. 19 shows the string 128 lowered so that latch 118 is back inside float shoe 110 and secured and a follow on pressure buildup blows a passage through the plug 138 so that the assembly is ready for cementing as shown in FIG. 20 . In FIG. 20 cement 145 is delivered through passages 112 and 114 at a pressure that keeps the piston assembly 122 ports closed. After cement 145 is delivered to annulus 133 up to location 146 on the liner 106 representing where expansion stopped, a wiper plug 148 is landed on the now opened plug 138 . Optionally some cement 145 can be pumped above plug 148 to ease subsequent drill out as shown in FIG. 20 .
[0076] Once again pressure is built up from the FIG. 20 position to cause latch 118 to release and to allow the swage assembly 120 held extended by piston assembly 122 that is now under pressure to be driven up through the already expanded portion to location 146 and then further up to the top of the liner 106 . The swage assembly 120 can optionally have a backup seal like a swab cup 150 shown in FIG. 20 so that it can keep a seal while driven up to the location 146 where expansion will continue until the hanger/packer 126 is against the casing 100 , as shown in FIG. 21 , and for continued movement until the entire liner 106 is expanded and all the expansion equipment is removed as shown in FIG. 22 . At that point the float shoe 110 can be milled out.
[0077] FIG. 23 starts an embodiment that tracks the previous embodiment only without cementing and instead using an open hole packer to seal the annulus around the expanded liner. As before a casing 200 is above an open hole 202 that is drilled or 204 if it is under-reamed. A rig 206 is at the surface 208 . As shown in FIG. 24 , the liner string 210 has a hanger/packer 212 for eventual support and sealing contact with the casing 200 and one or more external open hole packers 214 such as for example FORMpac® or REPacker® sold by Baker Oil Tools. At the lower end of the liner 210 is a float shoe 216 with a one way valve 218 and side outlets 220 and a lower port 220 A. A latch assembly 222 is latched into the float shoe 216 for ultimate support of the liner 210 as will be explained below. Going uphole there is an adjustable swage assembly 224 with a piston operating assembly 226 and a connector profile 228 . FIG. 25 illustrates a running string 230 with a connector 232 at its lower end adapted to contact connector profile 228 for a supporting and sealed connection to allow running in the liner 210 to the pilot hole 234 as shown in FIG. 26 . As stated before for an alternative, the assembly that is above the float shoe 216 can be run into the liner 210 after the liner is assembled in the wellbore 202 or 204 . In FIG. 26 , string 230 is used to lower liner 210 while circulation represented by arrows 236 and 238 flowing through lateral outlets 220 and lower port 220 A facilitate the advancement of the liner 210 . A debris barrier 240 prevents debris from entering the liner 210 during circulation as it is advanced into the wellbore.
[0078] In FIG. 27 a plug 242 is landed to allow pressure buildup in the string that is represented by arrow 244 , This pressure actuates the piston assembly 226 to increase the size of the swage assembly 224 and to create a bump out 246 in the liner 210 . As shown in FIG. 28 further pressure increase and set down weight releases the latch assembly 222 so that the swage assembly 224 start being powered uphole with pressure and/or overpull. An optional seal such as a swab cup 248 could be used with the swage assembly 224 in the event that the swage assembly itself will not sufficiently seal against the liner it is trying to expand as better illustrated in FIG. 29 . Also in FIG. 29 the swage assembly is moved up the substantial length of the liner 210 with the result being that the open hole packer 214 is sealed against the open hole 202 . Multiple open hole packers can be run. Because there is no cementing in this embodiment, the swage assembly can be driven continuously until the hanger/packer is set against the casing 200 as shown in FIG. 30 . The expansion equipment is removed as shown in FIG. 31 out the top of the liner 210 and the float shoe 216 can be milled out.
[0079] The remaining FIGS. focus on some applications of the techniques described above. FIG. 32 shows a parent casing 300 and more hole drilled that can include under reaming as represented by 301 or simply an extension of the hole that is the size of the parent casing 300 as represented by the dashed line in FIG. 32 . This view was previously illustrated in other FIGS. discussed earlier.
[0080] FIG. 33 is a split view indication that liner 302 is hung off the casing 300 using a hanger/packer 320 . At the lower end is a shoe 303 . The view is split showing that liner 302 is sealed with cement 304 on the left or with an external packer or seal 305 on the right as an alternative. As another alternative the cement 304 and seal 305 can be used together. There can be one or more seals 305 employed. The packer 305 can seal either to the smaller or larger bore such as 301 depending on how the hole is drilled and which sealing device is used.
[0081] FIG. 34 shows the liner 302 expanded and hung off the parent casing 300 and the shoe 303 drilled out with the annulus around the liner 302 isolated. More hole 310 is drilled which could be a straight bore or an under reamed bore as actually shown.
[0082] FIG. 35 shows a second liner 311 through the expanded liner 302 and hung off the parent casing 300 . Although the liner 311 is shown cemented, it could also be in open hole without cement and it could be slotted. Alternatively it could be hung off liner 302 but hanging off the casing 300 allows a larger inside diameter for liner 311 . Additionally, the hanging of liner 311 from casing 300 allows for subsequent flow to be isolated from the expanded liner 302 which might have not have the required pressure capacity or corrosion resistance. The extension bore if under reamed allows lower circulation pressure when cementing the production liner 311 . The staging of the liners 302 and 311 allows different mud weights to be used to account for differing formation properties so as to avoid mud loss or formation damage during drilling and subsequent running of the string 311 .
[0083] FIG. 36 shows a casing patch application where the casing 400 has a break or a crack or is otherwise damaged 401 and a section of tubular 402 can be inserted into position and expanded by the techniques described above so that pair of straddling seals 403 are disposed on opposed sides of the break 401 . Alternatively, longer continuous seals can be expanded to cover the damaged sections in place of straddling. Alternatively, the tubular 402 can be expanded into the inside wall of the casing 400 without seals such as 403 and simple expansion results in a tight seal that can be metal to metal.
[0084] FIG. 37 illustrates an open hole patch application where additional hole 411 has been drilled past the casing 410 and in the open hole region there is a fluid loss zone, water or other undesirable fluid is being produced into the wellbore, and/or sloughing formation. The tubular patch 412 can be run in and expanded in the manner shown before with the use of external packers 413 to straddle the zone where the losses or unwanted inflow or sloughing is occurring. Alternatively, longer continuous seals can be expanded to cover the damaged sections in place of straddling. It should be noted that there may be a reduction in the drift diameter in the patch 412 as compared to the drift diameter of the casing 420 which will restrict the passage of bit and drill string assemblies, possibly leading to a smaller open hold being drilled below the open hole patch. However, FIG. 38 is the same view as FIG. 37 with the drilled hole 411 having been under reamed in the troublesome zone so that after expansion of the patch 412 to engage the seals 413 the drift diameter of the patch is at least as large as the drift diameter in the casing 420 and maintains the bit passage diameter for continuous drilling of the hole further.
[0085] FIG. 39 starts another sequence of views with a cased hole 430 and an under reamed open hole 431 below it. In FIG. 40 a liner 432 has been inserted and expanded to two diameters or possibly more diameters depending on the cone capabilities. The smaller diameter is in casing 433 and the larger diameter is in the under reamed open hole 431 below. As covered before, a shoe 434 can be run if cement 435 is the option selected or if the alternative of external packers 436 is used. In either even the shoe provides a seat as a part of the expansion process previously discussed. The inside dimension of the liner 437 in the open hole is at least as large as its inside diameter inside the casing 433 . In FIG. 41 the shoe 434 is drilled out and additional hole 438 is drilled with a possible variation of the degree of under reaming which accounts for the dashed and solid line in the FIG. The innermost dashed line 439 represents the hole that would be made with the largest bit to fit through the top of the liner 432 while the next series of dashed lines represent under reaming to get the inside dimension of the lower end 437 of the same liner that had previously been expanded into an under reamed portion of the well above. The solid line represents a continuation of the bore size above. FIG. 42 shows another tubular 440 which can be the production string inserted and optionally cemented with cement 441 although it could be left in open hole without cement. Essentially what will pass through the top 432 of the liner above can be used. Again the lower bore size depends on formation conditions and whether cementing is to be done. In FIG. 42 the hole is under reamed to be about the size of the expanded portion 437 of the liner above. The string 440 is hung and/or sealed off inside the casing 442 but could optionally be hung off the bell portion 437 of the upper liner. The latter is illustrated in FIG. 43 where the second liner 446 is expanded and hung and/or sealed off at 445 to the already expanded liner above and in the enlarged bell portion. The string 446 can be cemented 448 or sealed with external packers 447 . At the top, it can be hung from the bell of the previously expanded liner above using a hanger/packer 445 . Note that there is no reduction in drift size as between the smallest dimension of the liner above 432 and the expanded dimension of the string 446 . This is due to the lower string 446 being hung off in the bell of the liner above at hanger/packer 445 .
[0086] In FIG. 44 the upper and lower liners are expanded to two or more different dimensions. The lower liner is hung with hanger packer 452 in the bell of the liner above it. The lower portion 453 of the lower liner is flared out so that the choke points for flow are at the hanging areas of both liners and in each case there is no reduction of drift regardless how many strings are run and sequentially hung from the string above. Here again the option of cementing 455 or using an external packer or packers 454 is also illustrated. The process can be repeated to add additional expandable liners until depth is reached. Open hole production can be another option.
[0087] FIG. 45 shows a progression of FIG. 44 where the second liner 456 has been drilled out and the open hole 457 has been under reamed to accommodate another expandable liner. The third liner 458 is shown off bottom due to a collapse of the open hole 459 . Alternatively, the liner could become stuck in the open hole for a variety of reasons including differential sticking and fill. Although the third liner 458 did not reach its targeted depth, it is still able to be expanded in two or more dimensions, maintaining flexibility for further wellbore construction. The extended recess section length of the previous liner 456 accommodates the length that the third liner 458 is set high by means of a longer liner lap. It can therefore be seen that the extended recess diameter section of the previous liner increases the flexibility of operations and mitigates risk beyond that of a shorter recess length. If a shorter recess length were present in the second liner 456 , then the third liner 458 would not have been able to be expanded without restricting the pass through diameter.
[0088] FIG. 46 is a further embodiment of the operational flexibility and risk mitigation provided by the extended recess diameter length. A third liner 460 has been installed into the wellbore below a second expandable liner 461 . The third liner 460 is shown in a no longer useable form as collapsed. Alternatively, the third liner could be leaking, not fully expanded, or otherwise damaged. Alternatively, the open hole below an undamaged third liner 460 could render the third liner unusable if for example the open hole stopped producing hydrocarbons, started producing water, or opened up for fluid losses. The sidetrack technique is then employed above the third liner 460 milling a window out of the side of the second liner 461 in a section that has been expanded to the recess diameter. After the window is milled the open hole section is further drilled and under reamed as required to accommodate running in a fourth liner 463 out of the window. The fourth liner is expanded in two or more dimensions and a hanger packer 462 is hung and/or sealed off in the recess diameter section of the second liner 461 . The section of the fourth liner 463 outside of the milled window in the second liner 461 is able to be expanded to the recess diameter. Open hole isolation for the fourth liner 463 is accomplished with cement 464 and/or the use of open hole packer or packers 465 . The bottom of the fourth liner 463 has been drilled out for further wellbore construction. All of the operational flexibility and risk mitigation provided by the two or more dimension expansion of the fourth liner and the recess resulting can be utilized in further wellbore construction such as: several additional Monobore liners are able to be run, ability to perform additional sidetracks, ability to set subsequent liners off of bottom, and running production strings of pipe to produce reservoirs without reducing the size of these production strings due to restricted pass through.
[0089] FIG. 47 shows and upper casing 470 that has a bell at the lower end either in the condition installed or due to expansion into it of the first liner to be hung. In FIG. 45 there is no liner in the hole but the FIG. is intended to be schematic of both ways a bell can be formed. FIG. 48 shows a liner 473 hung with hanger/packer 472 in the bell of casing 470 . Again the shoe is used to expand the string 473 and to facilitate cementing 476 or use of an external packer or packers 475 or both or neither if production will occur from open hole. FIG. 49 shows the shoe 474 drilled out and the hole 477 extended to the diameter of the expanded liner above. It can be under reamed to make it even larger should the formation characteristics and the cement delivery pressure be an issue. Running clearance could also be an issue that would warrant under reaming for running in of the liner 478 shown in FIG. 50 . The production liner 478 can be cemented 479 or it can be in open hole without cement or sealed with external packers. The string 478 is hung off the smaller dimension of the casing above the bell where the upper liner is supported. As a result of two dimension expansion of the upper liner with the upper end in the bell of the casing and the upper wellbore under reamed, the resulting internal dimension to depth is not reduced and the use of the upper liner for staged completion of the well does not narrow the size of the production liner 478 which is dictated by the casing size where the production liner 478 is shown to be supported in FIG. 50 .
[0090] FIGS. 51-54 show a progression of the wellbore construction concepts shown in FIGS. 47-50 in which the subsequent liner also contains a bell for the sake of being able to repeat the process multiple times without restriction of pass through. FIG. 51 shows and upper casing 480 that has a bell 481 at the lower end either in the condition installed or due to expansion into it of the first liner to be hung. In FIG. 51 there is no liner in the hole but the FIG. is intended to be schematic of both ways a bell can be formed. FIG. 52 shows a liner 483 hung with hanger/packer 482 in the bell 481 of casing 480 . Again the shoe 484 is used to expand the string 483 and to facilitate cementing 486 or use of an external packer or packers 485 or both or neither. FIG. 52 shows a bell section at the bottom of the liner 483 that is created either as a part of the process of expansion of this string or upon the installation of subsequent liner. FIG. 53 shows the shoe 484 drilled out and the hole 487 drilled out and under reamed as above. FIG. 54 shows the installation of a second liner 489 hung with a hanger/packer 488 in the bell of the previous liner. Zonal isolation is shown to be performed either with cement 492 , one or more open hole packers 490 , or both or neither. The second liner 489 contains a bell section 491 as the previous liner that can be used to hang off subsequent liners without restricting the wellbore.
[0091] Those skilled in the art will appreciate that the various embodiments offer many advantages that include improved circulation from the lateral ports in the float shoe and a fast drill out from using soft materials for the float shoe. There is an ability to transmit torque through the liner string as it is being advanced right down to the float shoe. Using an adjustable swage removes the need for a bell portion in the liner assembly reducing surge/swab effects. The liner is substantially expanded prior to cementing making for a smaller volume to cement with shorter pump times and earlier compressive strength. The balance of the expansion to tie the liner to the casing is not done against cement. The adjustable swage also allows removal through the liner at any time should the full expansion of the liner become impossible for some reason.
[0092] The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below. | An expansion and cementing assembly is run into the well as the expandable liner is made up. A work string is tagged into the expansion assembly and run to depth. Pressure drives the swage to initially expand and move uphole with the attached work string until the liner is expanded above the location of the subsequent cement placement. The assembly is then lowered to engage the guide/float shoe to perform the cementing step. The swage assembly is then released from the guide/float shoe and the balance of the expansion is performed without further expansion against the recently placed cement. The expansion assembly can start at the guide/float shoe or higher, in which case expansion can occur initially in a downhole direction and later be completed in an uphole direction. Variations without cementing are also contemplated. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method for processing a stamp material, and more particularly, to a hot-pressing method for processing a stamp material.
[0002] In conventional processes for processing a photosensitive stamp material, an article is formed out of a mixture including evenly mixed resin, photosensitive additive and filler by coaction of heat and pressure. The formed article is then disposed in a solvent to dissolve the filler out of the formed article, such that a sheet of porous stamp material is formed. After ink is injected into the stamp material on which a print surface has been formed, the ink may automatically seep toward the imprinting surface via micropores in the stamp material. In use, a seal can be formed on paper by simply pressing the stamp onto the paper. As to this type of stamp material, it is well known that high density stamp material can achieve a high clearness of seals, but can cause a low ink injection (i.e., seepage) speed and hence a prolonged length of time for the ink to be seeped to the print surface, i.e., a low ink injection efficiency; on the other hand, low density stamp material can achieve a high ink seepage speed and hence a high ink injection efficiency, but can cause a low clearness of the seals. In order to improve the clearness of the seal and the ink injection speed, a stamp combining stamp materials of different density has been proposed. In the proposed stamp, a layer of high density stamp material is disposed on one side of a low density stamp material and serves as a print surface of the stamp to achieve increased clearness of the seal. However, although the proposed stamp can improve the clearness of seal, the production of the stamp is complex and results in a high cost and therefore needs to be further improved. Moreover, in use of the conventional stamps, if too much ink is seeped over the print surface, the ink may soak into the paper at edges of seal characters, causing the seal to be blurred. What is needed, therefore, is an improved method for processing a stamp material which can overcome at least some of the drawbacks in the conventional technology.
BRIEF SUMMARY OF THE INVENTION
[0003] Embodiments of the present invention provides a hot-pressing method for processing a stamp material which can achieve a high clearness of the seal.
[0004] The method for processing the stamp material may generally include: heating one of a pressing member and a surface layer of the stamp material; pressing the surface layer of the stamp material using the pressing member; and cooling the stamp material to normal temperature.
[0005] In one embodiment, the pressing member or the surface layer of the stamp material may be heated to a temperature of 70° C. to 100° C. The pressing member may be heated to a temperature of about 100° C. to ensure that the surface layer of the stamp material can reach a temperature of 80° C. to 90° C. by heat conduction and radiation. Alternatively, the surface layer of the stamp material may be heated to a temperature of 80° C. to 90° C. The selected stamp material may be a dry and porous stamp material with a relatively low density. The pressing member may be a metal plate, a roller, or a metal screen. Alternatively, the pressing member may be a metal plate or roller having an accidented surface as fine as the metal screen.
[0006] One of a wide variety of processes can be used in carrying out the method described above. These processes may include, but not limited to, a pressing process, a pressing process in conjunction with a screen, a rolling process, a rolling process in conjunction with a screen, a high temperature vapour heating process and an infrared heating process.
[0007] In the pressing process, a stamp material is first placed on a planar table. A planar metal plate having a temperature of 80° C. to 90° C. is used to press a surface layer of the stamp material. The compression of the stamp material being compressed by the metal plate may be about 0.05 to 0.5 cm, and the pressing time may be controlled to be within 1 to 5 seconds. Then, the planar plate is removed, and the stamp material is cooled to achieve the processed stamp material.
[0008] In the pressing process in conjunction with a screen, a stamp material is first placed on a planar table. A 200 to 600-mesh screen is placed over the stamp material. A planar metal plate having a temperature of 80° C. to 90° C. is used to press the screen and a surface layer of the stamp material. The compression of the stamp material being compressed by the metal plate may be about 0.05 to 0.5 cm, and the pressing time may be controlled to be within 1 to 5 seconds. Then, the planar plate and the screen are removed, and the stamp material is cooled to achieve the processed stamp material.
[0009] In the rolling process, a stamp material is placed on a planar table. A roller having a temperature of 80° C. to 90° C. is used to roll a surface layer of the stamp material. The compression of the stamp material being compressed by the roller may be about 0.05 to 0.5 cm, and the rolling speed may be controlled to be 5 cm/second. Then, the stamp material is cooled to achieve the processed stamp material.
[0010] In the rolling process in conjunction with a screen, the stamp material is placed on a planar table. A 200 to 600-mesh screen is placed over the stamp material. A roller having a temperature of 80° C. to 90° C. is used to roll a surface layer of the stamp material. The compression of the stamp material being compressed by the roller may be about 0.05 to 0.5 cm, and the rolling speed may be controlled to be 5 cm/second. Then, the stamp material is cooled to achieve the processed stamp material.
[0011] In the high temperature vapour heating process, a stamp material is placed on a planar table. A surface layer of the stamp material is heated by spraying a high temperature vapour onto the surface layer. The vapour spray amount and spray time may be controlled such that the surface layer of the stamp material is heated to a temperature of 80° C. to 90° C. A planar plate at a normal temperature is used to press the surface layer of the stamp material. The compression of the stamp material being compressed by the planar plate may be about 0.05 to 0.5 cm, and the pressing time may be controlled to be within 1 to 5 seconds. Then, the stamp material is cooled and dried to achieve the processed stamp material.
[0012] In the infrared heating process, a stamp material is placed on a planar table. An infrared heater is used to heat a surface layer of the stamp material. The power of the infrared heater and heating time may be controlled such that the surface layer of the stamp material is heated to a temperature of 80° C. to 90° C. A planar plate at a normal temperature is used to press the surface layer of the stamp material. The compression of the stamp material being compressed by the planar plate may be about 0.05 to 0.5 cm, and the pressing time may be controlled to be within 1 to 5 seconds. Then, the stamp material is cooled to achieve the processed stamp material.
[0013] As described above, the pressing member may be a metal plate, a roller, or a metal screen. The surface layer of the stamp material may be heated by the heat transferred from the pressing member by heat-conduction and heat-radiation, or may alternatively be heated by high temperature vapour or an infrared heater. Since the stamp material at 80° C. to 90° C. is in a soften state but remains unmolten, by the coaction of the pressure and heat, the micropores in the surface layer of the stamp material are deformed to decrease the size of the micropores, which results in the density of the surface of the stamp material being increased. The increased density of the surface material allows for clearer seals to be formed, while maintaining the high ink injection speed because the density of the material under the surface is not changed. The compressed stamp material may have an about 0.1 to 5 mm reduction in thickness.
[0014] The method of the embodiments may have the following independent advantages. Due to the use of simple processing method, only very simple processing tools are required to form a high density layer, which serves as an engraving print surface of a stamp, on a surface layer of a sheet of stamp material. Because a high density printing surface can achieve clearer seals, the present invention can achieve stamp materials having an excellent seal-making result through a simple processing method. Moreover, with the present method, the surface layer of the stamp material can be formed with a regularly accidented surface having bumps and recesses. In use, ink is seeped out from print surface at the bumps while no ink or less ink is seeped out from the print surface at the recesses, thereby better controlling the amount of the ink seepage. As such, the ink soakage into the paper can be greatly diminished, and clearer seals can be formed as a result.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 illustrates a pressing process according to a first embodiment of the present invention in which reference numeral 1 denotes a planar table, reference numeral 2 denotes a stamp material, reference numeral 3 denotes a heated planar metal plate, and the arrow denotes a downward pressing direction of the planar metal plate.
[0016] FIG. 2 illustrates a pressing process in conjunction with a screen according to a second embodiment of the present invention in which reference numeral 1 denotes a planar table, reference numeral 2 denotes a stamp material, reference numeral 3 denotes a heated planar metal plate, reference numeral 4 denotes a metal screen, and the arrow denotes a downward pressing direction of the planar metal plate.
[0017] FIG. 3 illustrates a pressing process according to a third embodiment of the present invention in which reference numeral 1 denotes a planar table, reference numeral 2 denotes a stamp material, reference numeral 5 denotes a roller, and the arrow denotes a rolling direction of the roller 5 .
[0018] FIG. 4 illustrates a rolling process in conjunction with a screen according to a fourth embodiment of the present invention in which reference numeral 1 denotes a planar table, reference numeral 2 denotes a stamp material, reference numeral 4 denotes a metal screen, reference numeral 5 denotes a roller, and the arrow denotes a rolling direction of the roller 5 .
DETAILED DESCRIPTION OF THE INVENTION
[0019] Embodiments of the present invention generally employ a pressing member to press a stamp material. The pressing member or a surface layer of the stamp material may be heated to a temperature within 70° C. to 100° C., and preferably, within 80° C. to 90° C. The temperature of the pressing member may also be approximately 100° C. to ensure that the surface of the stamp material can reach a temperature of 80° C. to 90° C. by heat conduction and radiation. The selected stamp material may be a dry and porous stamp material. The pressing member may be a metal plate, a roller, or a metal screen. The surface of the stamp material may be heated by the heat transferred from the pressing member by heat-conduction and heat-radiation, or may alternatively be heated by high temperature vapour or an infrared heater. The stamp material at 80° C. to 90° C. is in a soften state but remains unmolten, and the operating temperature of the present invention may vary with the plastic temperature of different porous stamp materials. By the coaction of the pressure and heat, the micropores in the surface of the stamp material are deformed to decrease the size of the micropores, which results in the density of the surface of the stamp material being increased. The increased density of the surface material allows for clearer seals to be formed, while maintaining the high ink injection speed because the density of the material under the surface layer remains unchanged.
First Embodiment
[0020] Referring to FIG. 1 , a pressing process is illustrated in carrying out the present method for processing a stamp material. A stamp material 2 is placed on a planar table 1 . A planar metal plate 3 having a temperature of 80° C. to 90° C. is used to press a surface layer of the stamp material 2 . In particular, the compression of the stamp material 2 being compressed by the metal plate 3 is about 0.05 to 0.5 cm, and the pressing time is controlled to be within 1 to 5 seconds. The heat of the metal plate 3 is transferred to the surface layer of the stamp material 2 by heat-conduction and heat-radiation, causing the surface layer of the stamp material 2 to reach a temperature of 80° C. to 90° C. At the temperature of 80° C. to 90° C., the surface layer of the stamp material 2 is in a soften state but remains unmolten. By the coaction of the heat and pressure, the surface layer of the stamp material 2 is compressed such that the micropores in the surface layer of the stamp material 2 are deformed to decrease the size of the micropores, which, accordingly, results in the density of the surface layer of the stamp material being increased. Thereafter, the metal plate 3 is removed, and the stamp material is cooled to a normal temperature. The cooled stamp material may have a 0.1 to 5 mm reduction in thickness. Preferably, in this illustrated embodiment, the stamp material has a 0.2 mm reduction in thickness. The surface layer with increased density serves as the print surface, which allows for clearer seals to be formed.
Second Embodiment
[0021] Referring to FIG. 2 , a pressing process in conjunction with a screen is illustrated in carrying out the present method for processing a stamp material. A stamp material 2 is placed on a planar table 1 . A screen 4 is placed over the stamp material 2 . The screen 4 is of 200 to 600-mesh, and preferably, in this illustrated embodiment, of 400-mesh. A planar metal plate 3 having a temperature of 80° C. to 90° C. is used to press the screen and a surface layer of the stamp material 2 . In particular, the compression of the stamp material 2 being compressed by the metal plate 3 is about 0.05 to 0.5 cm, and the pressing time is controlled to be within 1 to 5 seconds. The heat of the metal plate 3 is transferred to the surface layer of the stamp material 2 by heat-conduction and heat-radiation, causing the surface layer of the stamp material 2 to reach a temperature of 80° C. to 90° C. At the temperature of 80° C. to 90° C., the surface layer of the stamp material 2 is in a soften state but remains unmolten. By the coaction of the heat and pressure, the surface layer of the stamp material 2 is compressed such that the micropores in the surface layer of the stamp material 2 are deformed to decrease the size of the micropores, which, accordingly, results in the density of the surface layer of the stamp material being increased. Thereafter, the metal plate 3 and the screen 4 are removed, and the stamp material is cooled to a normal temperature. The cooled stamp material may have a 0.1 to 5 mm reduction in thickness. Preferably, in this illustrated embodiment, the stamp material has a 0.2 mm reduction in thickness. The surface layer with increased density serves as the print surface, which allows for clearer seals to be formed. In use of stamps, if too much ink is seeped over the print surface, the ink may soak into the paper at edges of the stamp and blur the seal formed on the paper. In this illustrated embodiment, with the use of the 400 -mesh screen and by the coaction of the heat and pressure, the surface layer of the stamp material is formed with a regularly accidented surface having bumps and recesses. In use, ink is seeped out from print surface at the bumps while no ink or less ink is seeped out from the print surface at the recesses, thereby controlling the amount of the ink seepage. As such, the ink soakage into the paper can be diminished, and clearer seals can be formed as a result.
Third Embodiment
[0022] Referring to FIG. 3 , a rolling process is illustrated in carrying out the present method for processing a stamp material. A stamp material 2 is placed on a planar table 1 . A roller 5 having a temperature of 80° C. to 90° C. is used to roll a surface layer of the stamp material 2 . In particular, the compression of the stamp material 2 being compressed by the roller 5 is about 0.05 to 0.5 cm, and the rolling speed is controlled to be 5 cm/second. The heat of the roller 5 is transferred to the surface layer of the stamp material 2 by heat-conduction and heat-radiation, causing the surface layer of the stamp material 2 to reach a temperature of 80° C. to 90° C. At the temperature of 80° C. to 90° C., the surface layer of the stamp material 2 is in a soften state but remains unmolten. Under the coaction of the heat and pressure, the surface layer of the stamp material 2 is compressed such that the micropores in the surface layer of the stamp material 2 are deformed to decrease the size of the micropores, which, accordingly, results in the density of the surface layer of the stamp material being increased. Thereafter, the roller 5 is removed, and the stamp material is cooled to a normal temperature. The cooled stamp material may have a 0.1 to 5 mm reduction in thickness. Preferably, in this illustrated embodiment, the stamp material has a 0 . 2 mm reduction in thickness. The surface layer with increased density serves as the print surface, which allows for clearer seals to be formed.
Fourth Embodiment
[0023] Referring to FIG. 4 , a rolling process in conjunction with a screen is illustrated in carrying out the present method for processing a stamp material. A stamp material 2 is placed on a planar table 1 . A screen 4 is placed over the stamp material 2 . The screen 4 is of 200 to 600-mesh, and preferably, in this illustrated embodiment, of 400-mesh. A roller 5 having a temperature of 80° C. to 90° C. is used to roll a surface layer of the stamp material 2 . In particular, the compression of the stamp material 2 being compressed by the roller 5 is about 0.05 to 0.5 cm, and the rolling speed is controlled to be 5 cm/second. The heat of the roller 5 is transferred to the surface layer of the stamp material 2 by heat-conduction and heat-radiation, causing the surface layer of the stamp material 2 to reach a temperature of 80° C. to 90° C. At the temperature of 80° C. to 90° C., the surface layer of the stamp material 2 is in a soften state but remains unmolten. By the coaction of the heat and pressure, the surface layer of the stamp material 2 is compressed such that the micropores in the surface layer of the stamp material 2 are deformed to decrease the size of the micropores, which, accordingly, results in the density of the surface layer of the stamp material being increased. Thereafter, the roller 5 and the screen 4 are removed, and the stamp material is cooled to a normal temperature. The surface layer with increased density serves as the print surface, which allows for clearer seals to be formed. In use of stamps, if too much ink is seeped over the print surface, the ink may soak into the paper at edges of the seal characters and blur the seal formed on the paper. In this illustrated embodiment, with the use of the 400-mesh screen and by the coaction of the heat and pressure, the surface layer of the stamp material is formed with a regularly accidented surface having bumps and recesses. In use, ink is seeped out from print surface at the bumps while no ink or less ink is seeped out from the print surface at the recesses, thereby controlling the amount of the ink seepage. As such, the ink soakage into the paper can be greatly diminished, and clearer seals can be formed as a result.
Fifth Embodiment
[0024] In this embodiment, a high temperature vapour heating process is used in carrying out the present method for processing a stamp material. A stamp material is placed on a planar table. A surface layer of the stamp material is heated by spraying a high temperature vapour onto the surface layer. The vapour spray amount and spray time are controlled such that the surface layer of the stamp material is heated to a temperature of 80° C. to 90° C. A planar plate at a normal temperature is used to press the surface layer of the stamp material. In particular, the compression of the stamp material being compressed by the planar plate is about 0.05 to 0.5 cm, and the pressing time is controlled to be within 1 to 5 seconds. At the temperature of 80° C. to 90° C., the surface layer of the stamp material is in a soften state but remains unmolten. By the coaction of the heat and pressure, the surface layer of the stamp material is compressed such that the micropores in the surface layer of the stamp material are deformed to decrease the size of the micropores, which, accordingly, results in the density of the surface layer of the stamp material being increased. Thereafter, the planar plate is removed, and the stamp material is cooled and dried. The cooled stamp material may have a 0.1 to 5 mm reduction in thickness. Preferably, in this illustrated embodiment, the stamp material has a 0.2 mm reduction in thickness. The surface layer with increased density serves as the print surface, which allows for clearer seals to be formed.
Sixth Embodiment
[0025] In this embodiment, an infrared heating process is used in carrying out the present method for processing a stamp material. A stamp material is placed on a planar table. An infrared heater is used to heat a surface layer of the stamp material. The power of the infrared heater and heating time are controlled such that the surface layer of the stamp material is heated to a temperature of 80° C. to 90° C. A planar plate at a normal temperature is used to press the surface layer of the stamp material. In particular, the compression of the stamp material being compressed by the planar plate is about 0.05 to 0.5 cm, and the pressing time is controlled to be within 1 to 5 seconds. At the temperature of 80° C. to 90° C., the surface layer of the stamp material is in a soften state but remains unmolten. By the coaction of the heat and pressure, the surface layer of the stamp material is compressed such that the micropores in the surface layer of the stamp material are deformed to decrease the size of the micropores, which, accordingly, results in the density of the surface layer of the stamp material being increased. Thereafter, the planar plate is removed, and the stamp material is cooled and dried, and the cooled stamp material may have a 0.1 to 5 mm reduction in thickness. Preferably, the stamp material has a 0.2 mm reduction in thickness. The surface layer with increased density serves as the print surface, which allows for clearer seals to be formed.
[0026] It is to be understood that the embodiments illustrated above are only preferable embodiments in carrying out the present method. In practicing the present method, the pressing member for pressing the stamp material may be a planar plate with a screen mounted thereon, or alternatively may be a planar metal plate having an accidented pressing surface (e.g., grit surface) as fine as the screen. Likewise, the roller for pressing the stamp material may be wrapped with a layer of metal screen. Alternatively, the surface of the roller for pressing the stamp material may be formed with an accidented surface (e.g., grit surface) as fine as the screen. All of the above variations should be considered to be within the scope of the present invention. Therefore, in summary, the present invention provides a simple hot-pressing method which can change the structure of a print surface of a stamp material such that the density of the print surface is increased or the print surface is made to be accidented. By the present method, the ink injection amount over the print surface can be better controlled, such that ink soakage can be greatly diminished, and clearer seals can be formed.
[0027] 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 processing a stamp material generally includes: heating one of a pressing member and a surface layer of the stamp material; pressing the surface layer of the stamp material using the pressing member; and cooling the stamp material to normal temperature. | 1 |
FIELD
The present disclosure relates generally to a flue gas sensor for a gas-fired appliance and, more specifically, to an apparatus that measures exhaust gas parameter concentrations while maintaining a low ambient apparatus temperature during regular appliance operation.
BACKGROUND
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. Monitoring of flue gas parameters, such as carbon monoxide (“CO”), Nitrogen Oxides (“NOx”), and Oxygen (“O 2 ”) in a fuel fired appliance, such as a gas fired water heater, is desirable to alert surrounding inhabitants of specific levels of such exhaust gas parameters. Traditionally, such gas parameter monitoring was accomplished with a device located some distance away from the actual flow of hot, combusted flue gases. Such known devices, however, may not satisfactorily measure such gas parameters because they must be located away from the actual flow of the hot, post-combustion flue gases. This is because locating such a detection device in the actual flow of the combustion gases may subject the device to temperatures above 200 degrees Celsius, which may potentially damage the sensing instrument or its exterior casing. Locating a sensor away from the actual flow of combusted gases may delay detection, and locating a device in such a flow within a flue, may cause a sensor to become damaged and inoperable.
Additionally, when an exhaust gas parameter measuring device, such as a CO sensor, is located outside of the exhaust flow, in a reduced temperature zone, the device may only detect emission parameters when the combustion exhaust is blocked downstream of the detecting device, that is, blocked above the detecting device in a chimney. In such an instance, the exhaust flue gases are normally caused to “back up” and overflow outside of a draft hood until the combustion gases reach the detecting device located outside of the proximity of the exhaust flow. This may delay detection.
In the alternative, if the air intake, that is, the air upstream of a CO detecting device is restricted or blocked, but the exhaust flue downstream of a CO detecting device is not blocked, a CO gas detecting device located outside of the combustion exhaust flow is not capable of detecting exhaust gas CO levels that may result from improper combustion. This is because the exhaust flue is free from blockage and the flue gas parameter detecting device is located outside of the exhaust flow. The exhaust gas will not “back up” and alternatively flow toward such a device when only the airflow upstream of the sensor is compromised.
What is needed then is a device that does not suffer from the above limitations. This will result in an exhaust gas parameter detection device that detects gas parameters under all operating conditions, even when an exhaust flue is restricted downstream or upstream of the device.
SUMMARY
In accordance with the teachings of the present disclosure, an exhaust gas parameter sensor for a flue of a fuel fired appliance is disclosed. More specifically, an apparatus for detecting specific combustion gas parameter emissions, such as CO, NOx, and O 2 , from a gas fired appliance exhaust is disclosed. The combustion gas parameter sensor may be positioned under a draft hood, just below a chimney for the combustion exhaust gas of the fuel fired appliance, making the sensor susceptible to specific gas parameters in the exhaust gas.
Just above the top surface of the appliance of which a combustion gas parameter sensor is associated, an exhaust outlet is located, above which, a draft hood is located. The draft hood permits fresh air to be drawn into the exhaust stream within the draft hood and subsequently, the exhaust chimney. The combustion gas parameter sensor may be located under the draft hood where the sensor is subject to cooling by fresh air drawn into the draft hood, before the fresh air, mixed with combustion gas, passes into the chimney.
A bracket may be utilized to position the combustion gas parameter sensor under the draft hood. By using a bracket, the sensor may be positioned within the geometric confines of the draft hood, to make the sensor more susceptible to exhaust gas parameters. Furthermore, the bracket may position the sensor such that air is permitted to flow over all sides of the sensor, between the draft hood and the sensor, and between the sensor and the appliance top surface, so that cooling of the sensor is possible in its location proximate the exhaust stream.
Alternatively, the combustion gas parameter sensor may be located on an exhaust sampling tube, through a wall of which exhaust gas parameters may be sensed by the sensor. One end of the sampling tube may be positioned in the exhaust port, where exhaust gases are drawn in, while the other end may be positioned in the exhaust chimney, where sample exhaust gases are expelled. Sampled exhaust gases are cooled as they pass through the tube, which may coil around the top surface of the appliance.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
FIG. 1 is a partial cross-sectional side view of a water heater;
FIG. 2 is a side view of a water heater depicting a draft hood and example position of a combustion gas parameter sensor;
FIG. 3 is a perspective view of a water heater depicting a draft hood, flue pipe, exhaust chimney, and example location of a combustion gas parameter sensor; and
FIG. 4 is a perspective view of another embodiment depicting placement of a draft hood, exhaust flue, chimney and example placement of a combustion gas parameter sensor.
DETAILED DESCRIPTION
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
Referring now to FIGS. 1-4 and more specifically to FIG. 1 , the operative workings of the present disclosure will be depicted and explained. FIG. 1 depicts a conventional fuel fired water heater 10 , such as a gas fired water heater. Water heater 10 includes an outer housing 12 within which resides a water storage tank 14 , around which is a layer of insulation 16 . A gas fired burner assembly 18 resides at the bottom area of the water heater 10 that, when ignited, heats the water within water area 20 . The water storage tank 14 has a generally elongated cylindrical shape, the majority of which is positioned above burner assembly 18 . A generally conically shaped hood portion 22 is sealingly secured to a lower portion of tank 14 and lies around and generally above the burner assembly 18 . A lower end of an axially elongated flue pipe 24 is sealingly secured to hood portion 22 . The flue pipe 24 projects outwardly through outer housing 12 at the outer housing upper end 26 . Such projecting end of the flue pipe 24 serves as an exhaust outlet 24 . The flue pipe 24 directs smoke and combustion gases into a chimney 60 via a draft hood 27 .
In operation, combustion gases generated by the firing of burner assembly 18 are directed upwardly through flue pipe 24 via hood 22 and serve to transfer heat to the water contained in water area 20 within storage tank 14 . In many cases, a spirally shaped or zig zag baffle member 28 is supported within flue pipe 24 and serves to create a mixing of the combustion gases as they flow upwardly through flue pipe 24 . The baffle member 28 , by contributing to the mixing of combustion gases, improves heat transfer to the water by reducing any thermal boundary layer that may form along the internal surface 30 of flue pipe 24 .
The water heater 10 also includes suitable fittings 32 and 34 for facilitating the flow of water into and out of the water heater 10 . Specifically, fitting 32 is for connection of a cold water supply pipe to supply cold, unheated water to the tank 14 . Fitting 34 is for connection of a pipe to supply heated water to a home or facility after being heated in the water heater 10 . The water inlet 32 is provided with a dip tube 36 that directs the inflow of cold water to the bottom of the storage tank 14 .
Additionally, water heater 10 includes a control assembly 38 for controlling the supply of gas to burner assembly 18 in response to the sensed temperature of the water within storage tank 14 . A drain spigot and valve assembly 40 is also provided for enabling the user of the water heater 10 to periodically flush debris from the bottom of tank 14 as well as to drain the tank 14 in the event of any necessary maintenance. To actually heat water in the storage tank 14 , the burner assembly 18 is utilized in conjunction with control assembly 38 .
The burner assembly 18 heats the water in the storage tank 14 by utilizing a pilot light 42 , which produces a flame 44 , an igniter 46 , which is used to light the pilot light 42 , a gas line 48 that directs the flow of gas to the burner assembly 18 , and a flame sensor 50 . The flame sensor 50 is normally a device that sends a signal to the control assembly 38 upon sensing the presence of a flame 44 . The control assembly 38 is used by a user to govern the temperature of the water within the storage tank 14 and thus the amount and duration of natural gas supplied to the burner assembly 18 . Upon utilization of the burner assembly and the subsequent heating of water within water area 20 of the storage tank 14 , combustion gases from the flame 44 pass upward through the flue pipe 24 to the upper end 26 of the water heater 10 .
Once at the upper end 26 of the water heater 10 , the combustion gases exit the upper end 26 via the exhaust outlet 24 and pass into and through the draft hood 27 . The draft hood 27 is secured in place by a number of hood legs 52 . Each hood leg 52 has a hood foot 54 and a hood riser 56 that together serve to create an air gap 58 . The air gap 58 permits air to pass into the draft hood 27 to facilitate and hasten the passage of combustion gases into the chimney 60 . The warmed combustion gases exiting through the chimney 60 facilitate the drawing of air through the air gap 58 due to convection currents caused by the phenomenon of heat rising. As thus far described, water heater 10 is of a construction typical for gas water heaters currently in use. FIGS. 2-4 will now be more specifically referred to, in conjunction with FIG. 1 , to better depict the operative workings of the present invention.
FIGS. 2 and 3 depict an upper end 26 of a water heater 10 depicting a location of a combustion gas sensor 62 . As depicted, the combustion gas sensor 62 is located under the draft hood 27 , and more specifically, in FIG. 2 , the combustion gas sensor 62 is located under the slanted or angular portion of the draft hood 27 , relative to the upper end 26 , which is horizontal, of the water heater 10 . The combustion gas sensor 62 is positioned under the draft hood 27 by using a sensor bracket 63 . The sensor bracket 63 has a sensor bracket foot 64 and a sensor bracket riser 66 . The sensor bracket foot 64 is secured to the upper end 26 by using a suitable fastener, such as a screw, rivet or bolt. By utilizing a sensor bracket 63 , the combustion gas sensor 62 can be manipulated under the draft hood 27 for easy installation. Additionally, by making the combustion gas sensor 62 a separately positioned piece, advantages of the sensor 62 relative to the combustion gases are realized.
An advantage of the combustion gas sensor 62 and the sensor bracket 63 is that it can be added to any existing gas fired appliance where monitoring of specific gas parameters such as, but not limited to, CO, NOx and O 2 are desired to be monitored. Another advantage of the combustion gas sensor 62 is that its placement permits ambient air to be drawn over its entire surface to cool the sensor 62 , due to its placement in a position of elevated temperatures. More specifically, generally horizontal currents 68 are drawn around the combustion gas sensor 62 when the gas fired burner assembly 18 is fired and supplying heat to the water in the storage tank 14 . The generally horizontal air currents 68 are generated by the combustion gas vertical currents 70 , which result from the general burning of gas by the gas fired burner assembly 18 . When the heated combustion gasses rise through the flue pipe 24 and exit the flue pipe 24 , the gases continue upward, past the upper end 26 , into the draft hood 27 , and into the chimney 60 . The heated combustion gases are represented by the vertical currents 70 . The heat of the vertical currents causes generation of convection currents which results in the horizontal currents 68 being drawn from outside the draft hood 27 , into the draft hood 27 and subsequently up the chimney 60 to join and mix with the vertical currents 70 .
Because gas fired appliance combustion gases typically can reach 300 degrees C., placement of a combustion gas sensor near the combustion gases, or directly in the flow of the combustion gases, may result in malfunctioning of a combustion gas sensor or a shortened life span of such a sensor. However, with the arrangement depicted in FIGS. 2 and 3 , because the combustion gas sensor 62 is located away from the vertical currents 70 of the combustion gases but in the flow of horizontal currents 68 , the sensor 62 does not suffer from the disadvantages of being proximate to, or in, 300 degree C. combustion gases. By placing the combustion gas sensor 62 under the draft hood 27 as depicted in FIGS. 2 and 3 , horizontal currents are permitted to flow around all sides of the combustion gas sensor 62 . The currents can flow between the wall of the draft hood 27 and the sensor 62 , and between the sensor 62 and the upper end 26 . In this fashion, the life of the combustion gas sensor 62 can be prolonged, and combustion gases can be detected long before such gas might “back up” and spill out of the draft hood 27 .
Another advantage of the placement of the combustion gas sensor 62 as depicted in FIGS. 2 and 3 is that it can detect combustion gases at all times, that is, continually. More specifically, combustion gases are detectible when the gas fired appliance is normally operating or combusting, when the flue pipe is blocked downstream of the sensor 62 , and when there is blockage upstream of the sensor 62 .
Contrary to that depicted in FIGS. 1-4 , if a gas sensor, such as a CO detector, is located away from the draft hood, then CO is typically not detected until such CO gases “back up” and spill outside of the draft hood and reach a remote CO detector. This scenario normally would occur when, for instance, the appliance chimney is blocked. In another scenario, when there is blockage of the intake air around the burner assembly at the bottom of a water heater, then CO may not be detected at all since there is simply a blockage of air intake, even though combustion is not proper, which may result in combustion gas imbalances. In such a scenario, the combusted gases would pass through the appliance undetected, or back up at the bottom of the appliance, causing a delayed detection of elevated CO in the exiting combustion gases.
By placing the combustion gas sensor 62 as depicted in FIGS. 2 and 3 the forgoing scenarios are avoided, and flue gases can be detected before they spill out of the draft hood 27 or other possible appliance outlet. Although not shown, a wire or control cord connects the combustion gas sensor 62 to the control assembly 38 . In the event of unfavorable combustion flue gas detection, the combustion gas sensor 62 causes the control assembly 38 to shut off the gas fired appliance so that combustion is halted. FIG. 4 is another arrangement of a flue gas sensor that also permits flue gas detection, and will now be explained.
FIG. 4 depicts another arrangement of a flue gas sensor 72 . In such an arrangement, the flue gas sensor 72 fluidly communicates through a wall of a flue gas sampling tube 76 that is secured to the upper end 26 by a bracket 80 . A communication wire 74 effectively communicates the gas sampling findings to the control assembly 38 . In the event the gas sampling findings warrant shutting off of the appliance 10 , such as in the detection of an unsafe level of CO, the control assembly 38 will communicate with the burner assembly 18 to do such. The sensor 72 is located on the sampling tube 76 to permit the sensor 72 to be located away from the elevated temperatures of combusted flue gas, which may contribute to a shortened sensor life. A shortened sensor life is avoided, and in fact, sensor life is optimized by locating the sensor 72 on the gas sampling tube 76 . Not only is the sensor 72 located away from the heated combustion gas flow 82 of the combustion gases 82 exiting from the flue pipe 24 , but the sample gas 78 , or gas within the sampling tube 76 , is permitted to cool as the gas progresses through the sampling tube 76 . Heat is transferred from the sample gas 78 to the tube 76 and then into the air surrounding the tube 76 . To facilitate heat transfer, a material such as copper or aluminum may be used for the tube 76 , although other materials may be used. Furthermore, longer tube 76 lengths can be used when increased heat transfer is desired.
An advantage of the sampling tube 76 is that as the gas is permitted to pass through the sampling tube 76 , which coils around the upper end 26 of the heater 10 , the gas cools, which prolongs sensor 72 life. In the event of the necessity of a sampling tube 76 longer than that depicted in FIG. 4 , the sampling tube 76 may be coiled around the flue pipe 24 , outside the perimeter of the draft hood 27 , in multiple coils. By causing the sample gas 78 to travel farther through the sampling tube 76 , the heat transfer out of the sample gas 78 will continue before the gas reaches the sensor 72 .
In order for the combustion gas sensor 72 to be supplied with a steady flow of combustion gas, a first sample tube end 84 is inserted down into the flue pipe 24 while a second sample tube end 86 is inserted up into the chimney 60 . By arranging the tube in such a manner, the heated combustion gas 82 rising into the chimney 60 , draws sampling gas 78 through the sampling tube 76 , that is, in the first end 84 and out the second end 86 . The sampling gas 78 is forced into the sampling tube by the heated, rising gas 82 and further fostered by the drawing action at the second end 86 , which is caused by convection currents of the heated gas passing the second end 86 .
Another advantage of using the sampling tube 76 is that the combustion gas sensor 72 and sampling tube 76 may be installed as an add-on option to existing water heaters or other gas fired appliances not so equipped. The flue gas sensor depicted in the figures and described above may be any kind of combustion gas sensor. For instance, the sensors may sense CO, NOx, or O 2 parameters; however, other gas components may be sensed as such need becomes evident.
The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. | A fuel fired appliance exhaust gas parameter sensor for continually detecting gas parameter emissions, such as CO, NOx and O 2 , may be located above the appliance near the appliance exhaust outlet. The sensor may be located near or under a draft hood located near the exhaust outlet. The sensor remains relatively cool by draft air moving from outside the draft hood and into a chimney, the draft being hastened by the heated, rising chimney gases. A sensor bracket may be attached to the appliance and the sensor to appropriately position the sensor under the draft hood. Alternatively, the sensor may be located on a tube that continually samples combustion exhaust. The tube may be located outside of the draft hood perimeter to maintain a low sensor temperature, while multiple tube coils around the exhaust outlet may be used to further cool the sampled gas. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Divisional of U.S. application Ser. No. 10/719,461, filed Nov. 21, 2003, now U.S. Pat. No. 7,444,643, entitled “ACCESSING A ERP APPLICATION OVER THE INTERNET USING STRONGLY TYPED DECLARATIVE LANGUAGE FILES,” which is a Divisional of U.S. application Ser. No. 09/483,069, filed Jan. 14, 2000, now U.S. Pat. No. 6,854,120, entitled “ACCESSING A ERP APPLICATION OVER THE INTERNET USING STRONGLY TYPED DECLARATIVE LANGUAGE FILES,” both of which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to enterprise resource planning systems performed by computers, and in particular, to a method and apparatus for accessing an enterprise resource planning application over the Internet using Java.
2. Description of Related Art
With the fast growing popularity of the Internet and the World Wide Web (also known as “WWW” or the “Web”), there is also a fast growing demand for Web access to Enterprise Resource Planning (ERP). However, it is especially difficult to use ERP software with the Web. One of the problems with using ERP software on the Web is the lack of correspondence between the protocols used to communicate in the Web with the protocols used to communicate with ERP software.
For example, the Web operates using the HyperText Transfer Protocol (HTTP), the eXtensible Markup Language (XML), the eXtensible Style Language (XSL) and the HyperText Markup Language (HTML). The use of this protocol and languages result in the communication and display of graphical information that incorporates hyperlinks. Hyperlinks are network addresses that are embedded in a word, phrase, icon or picture that are activated when the user selects a highlighted item displayed in the graphical information.
HTTP is the protocol used by Web clients and Web servers to communicate between themselves using these hyperlinks. HTML is the language used by Web servers to create and connect together documents that contain these hyperlinks. The HTML syntax and commands are specified by the web browsers, and cannot be extended by users.
XML and XSL are anticipated to be the next generation of web languages. XML is the language used by Web servers to create and connect together documents that contain user defined structures. XSL is the language used by web browsers to convert XML documents into HTML for the purposes of display. The validity of an XML document is defined by a Document Type Definition (DTD), which an XML parser uses to ensure that an XML document is valid.
Web servers are extensible via a number of APIs. The Common Gateway Interface (CGI) is a standard interface for executing programs external to the web server. The Java language is a programming language and environment defined by Sun Microsystems. Java Servlets are a widely available interface for executing Java programs within the web server. Java Server Pages (JSP) is a web page interface for specifying Java commands that are to be executed in the web server. The Visual Basic Script (VB Script) language is a programming language defined by Microsoft. The Active Server Pages (ASP) interface is a web page interface specified by Microsoft for specifying VB Script commands that are to be executed in the web server.
In contrast, most ERP software provides an application programming interface (API) for accessing ERP functionality from external programs. Each vendor of an external program may have its own implementation of the API, for example, Peoplesoft has an API, called the Message Agent API.
Thus, there is a need in the art for methods of accessing Enterprise Resource Planning software across the Internet network, and especially via the World Wide Web. Further, there is a need for simplified development environments for such systems.
SUMMARY OF THE INVENTION
To overcome the limitations in the prior art described above, and to overcome other limitations that will become apparent upon reading and understanding the present specification, the present invention discloses a method and apparatus for executing pre-defined API calls in an ERP system via the Internet. In accordance with the present invention, Web users can request information from ERP software via HTML input forms, which request is then used to create a sequence of ERP API calls for execution by the ERP software. The results output by the ERP software are themselves transformed into HTML or XML/XSL format for presentation to the Web user. The specification of the ERP interface is done through the specification of ERP data definition.
One aspect of the invention provides a method for executing ERP application requests in a computer-implemented ERP data processing system via a network, comprising the steps of:
(a) transmitting a HyperText Markup Language (HTML) input form to a browser executed by a client computer in the network for display on a monitor attached thereto;
(b) receiving a HyperText Transfer Protocol (HTTP) request from the browser to access the ERP System, wherein the request optionally includes data entered by the user into an HTML input form;
(c) transferring any data entered by the user into the HTML input form and any data stored in the requested HTML page into the ERP application API;
(d) transferring control to the ERP application for execution;
(e) receiving output data from the ERP application in response to the transmitted data and request;
(f) merging the output data from the ERP application into a strongly typed Java object;
(g) transforming the strongly typed Java objects into a transmittable format, such as XML or HTML, and
(h) transmitting the HTML or XML object to the browser for display on the monitor attached to the client computer.
Preferably the merging step comprises the step of merging the output data from the ERP application into a strongly typed object form using an ERP Web Gateway, wherein the strongly typed object form comprises strongly typed Java objects.
In another aspect the HTML input form, dynamic ERP Application data access, Java objects definitions and HTML report form are stored in form of XML files; wherein the XML file strongly couples the data in the ERP Application to the Java objects and the XML file which specifies the presentation of the Application data.
Yet another aspect of the invention provides a method of converting ERP data in a database managed by an ERP application and accessed through an ERP API and ERP Message Agent API (MAAPI) to strongly typed data in Java objects comprising the steps of:
(a) reading a XML file containing the definition of the Java objects and their attributes; or HyperText Markup Language (HTML) statements which specifies presentation format;
(b) parsing each of the declarations and HTML statements to identify definitions of objects and their attributes; and
(c) creating the respective objects with their attributes
(d) populating the objects with data from the ERP data.
Preferably in this aspect of the method of the invention the creating and populating of Java objects step comprises the steps of:
(a) opening a connection through the ERP API to the ERP Message Agent API (MAAPI);
(b) setting the Application object identifier, username and password using the MAAPI
(c) setting search key values
(d) instructing the ERP application to process the current object
(e) for every scroll level creating a corresponding object and setting its attributes with data from the ERP Application data; and,
(f) closing the connection to the ERP API.
Yet another aspect of the invention provides a method of presenting strongly typed Java objects using HTML by merging Java objects with XML template files.
The invention also provides a client server ERP information handling system, for accessing by Internet, data managed by an ERP application comprising:
a client computer accessible to a user having a web browser adapted to send information, in an Internet acceptable language, from an ERP database to a user and to send requests destined for the ERP database;
a web server for sending the panels to and receiving the requests from the client computer;
an ERP web gateway in communication with the web server for converting the requests from the web server into language format required by an interface of the ERP application and to convert information received from the interface of the ERP; and,
an ERP application for controlling access to a database containing information requested by a user.
In addition another aspect of the invention provides an article of manufacture for use in a computer system comprising a computer readable medium for storing statements or instructions for use in execution in a computer in accordance with the aspects of the invention described above.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings in which like reference numbers represent corresponding parts throughout:
FIG. 1 schematically illustrates—the hardware environment of the preferred embodiment of the present invention;
FIG. 2 shows schematically an overview of the preferred embodiment of the present invention, and in particular, shows the interaction among components in the present invention;
FIGS. 3A & 3B (hereinafter referred to as FIG. 3 ) show schematically an overview of the preferred embodiment of the present invention, and in particular, show the relationship between the user runtime environment and the application development environment of the present invention;
FIG. 4 is a flowchart illustrating the steps involved in creating an ERP data definition used as data access code to access data in a database accessed by ERP API's;
FIG. 5 is a flowchart illustrating the steps involved in populating strongly typed objects that correspond to a weakly typed ERP object.
FIG. 6 shows a student course list panel and the fields associate with the panel.
FIG. 7 shows a strongly typed Student Course List Java Object.
FIG. 8 is a flowchart illustrating the steps involved in invoking strongly typed objects, and converting strongly typed objects into a format requested by a web client; and,
FIG. 9 depicts the defining of a sub-graph of data objects.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In the following description of the preferred embodiment, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration a specific embodiment in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional changes may be made without departing from the scope of the present invention.
Overview
With the fast growing popularity of the Internet and the World Wide Web (also known as “WWW” or the “Web”), there is also an increasing demand for Web access to enterprise resource planning software. One aspect of the present invention implements a ERP connector that facilitates communication between Web clients, Web servers, and servers executing ERP software such as PeopleSoft's Message Agent API. The ERP Web Connector enables an application developer to build Web applications for a database management system accessed through ERP software by using HTML pages and ERP API.
An end user of these applications sees only the web pages for his/her requests and the resulting reports. Users fill out the input forms, point and click to navigate the forms, and to access the ERP software. A complete sequence of API calls is dynamically built by the ERP Web Connector with the user inputs and sent to the server executing the ERP software. The API commands are performed by the ERP software, and the resulting output is merged by the ERP Web connector into the HTML forms for presentation to the user or XML documents for consumption by another application.
An application developer, XML based definitions of the ERP API and stores them in the ERP Web connector machine. The developer then executes a command to generate Java code that invokes the API, HTML pages containing Java Server page information, and template files—i.e. XSL—that format the ERP API results. The developer can modify these generated files to customize the output web page, the API results format, or the combine the Java code together for more complicated functionality. Since the ERP Web gateway uses native Web languages, and not some new or hybrid language, various off-the-shelf tools may be used for creation of Web pages.
Hardware Environment
FIG. 1 schematically illustrates the hardware environment of the preferred embodiment of the present invention, and more particularly, illustrates a typical distributed computer system using the Internet 10 to connect client systems 12 executing Web browsers to server systems 14 executing Web daemons, to connect the server systems 14 executing Web daemons to server systems 16 executing the ERP Web Connector, and to connect the server systems 16 executing ERP Web Connectors to server systems 18 executing the ERP Application. A typical combination of resources may include clients 12 that are personal computers or workstations, and servers 14 , 16 , and 18 that are personal computers, workstations, minicomputers, or mainframes. These systems are coupled to one another by various networks, including LANs, WANs, SNA networks, and the Internet.
A client system 12 typically executes a Web browser and is coupled to a server computer 14 executing a Web server. The Web browser is typically a program such as the IBM Web Explorer, or Netscape or the Microsoft Internet Explorer. The Web server 14 is typically a program such as the IBM HTTP Daemon or other WWW daemon. The client computer 12 is bi-directionally coupled with the server computer 14 over a line or via a wireless system. In turn, the server computer 14 is bi-directionally coupled with a ERP Web Connector (Web Gateway) 16 over a line or via a wireless system. In addition, the ERP Web Connector 16 is bi-directionally coupled with one or more ERP application servers 18 over a line or via a wireless system.
The ERP Web Connector 16 supports access to a server 18 executing ERP software. The ERP Web Connector 16 and ERP server 18 may be located on the same server as the Web server 14 , or they may be located on separate machines. The servers 18 executing the ERP software may be geographically distributed and may comprise different vendor systems, such as a PeopleSoft, SAP, BAAN, etc.
Those skilled in the art will recognize many modifications may be made to this configuration without departing from the scope of the present invention. For example, in two-tier configuration, the server system executing the functions of the ERP Web Connector 16 may also execute the functions of the Web server 14 and/or the ERP server 18 . Alternatively, in a three-tier configuration, the Web server 14 , ERP Web Connector 16 , and ERP server 18 may all be performed by different servers.
ERP Web Gateway
Referring to FIG. 2 , the ERP Web Gateway 16 is designed to be sufficiently flexible and powerful, yet be available on multiple platforms, such as OS/2, AIX, MVS, etc. as long as a Java Virtual Machine is available on the platform. Further, the ERP Web Gateway 16 is designed to work with existing Web and ERP application development tools, with minimal modifications required to such tools.
These goals led also to the development of the code generation and run-time environment of the present invention. The ERP Web Gateway introduces a interface object, the ERP Connector 17 , to map the procedural ERP Application native API. It also incorporates a mechanism that allows input data from an HTML-format input form to be inserted as parameters for the ERP Application. Another mechanism is incorporated to allow the ERP Application results to be merged into HTML report forms. The runtime engine of the ERP Web Gateway 16 reads the XML template files to generate the appropriate Java objects with their attributes and report forms. The use of XML instead of a new or hybrid language, allows the full expressive power without artificial limitations. Both object definitions and report forms can be laid out in any fashion as long as the specifications are conformed to the XML syntax.
Interaction Among Components
FIG. 2 shows schematically an overview of the preferred embodiment of the present invention, and in particular, shows the interaction among components in the present invention. The user interacts with the Web browser executing on a client computer 12 remotely located from the Web server 14 . At some point, the user executes an HTTP command via the Web browser on client 12 that results in communication with an HTTP daemon executing on the Web server 14 . The Web server 14 would then transmit an initial or home page in HTML format to the Web browser on client 12 for presentation to the user. The ERP Web Connector 16 would be invoked by the user selecting a hyperlinked item from the home page. The ERP Web Connector, 16 conforms to a web server interface, such as the Common Gateway Interface (CGI) defined for Web servers 14 , or the Java Servlet API and thus can be invoked from an HTML page in one of two ways: either by an HTTP anchor reference or by an HTTP form action.
An HTTP anchor reference would typically be formatted as follows: “<A HREF=http://{web-server}/{cgi-name}[?variable-name=variable-value & . . . ]>”.
An HTTP form action would typically be formatted in a similar manner as follows: “<FORM METHOD={method}ACTION=http://{web-server}/{c-gi-name}[?variable-name=variable-value & . . . ]>”.
In both of the above examples, the following parameters are used:
“{web-server}” identifies the Web server;
“{cgi-name} ” identifies the Common Gateway Interface (CGI) or Java Servlet interface to the ERP Web connector;
“{method} ” is either “GET” or “POST”, as specified under the HTML standard;
“[?variable-name=variable-value & . . . ]” are optional parameters that may be passed to the ERP web connector program
At some point in the interaction between the Web browser on client 12 , the Web server 14 , and the ERP Web gateway 16 , a user using the Web browser on client 12 would request data from a ERP application 18 a form request (an object request) is sent 30 from the client 12 to Web Server 14 , which forwards the object request to the ERP WWW gateway 16 which would retrieve any user inputs from the HTML input, retrieve any parameters specified in the web page, and retrieve data through the ERP Connector 17 , from the ERP application 18 , populate the set of strongly typed objects corresponding to the ERP data. The ERP Web gateway then either: 1) extracts an output template based on the web page parameters, converts the strongly typed objects to XML strongly typed objects, converts the XML objects to HTML using the output template, then transmits the HTML output page to the web server; 2) converts the strongly typed objects to XML strongly typed objects then transmits the XML outputs to the web server; 3) extracts an output template based on the web page parameters, converts the strongly typed objects to HTML using the output template, then transmits the HTML output page to the web server 14 . The Web server 14 transmits the HTML input form to the Web browser 12 for display to the user.
Development Environment
FIGS. 3A & 3B (hereinafter referred to as FIG. show schematically an overview of the preferred embodiment of the present invention, and in particular, show the relationship between the user runtime environment and the application development environment of the present invention.
As mentioned earlier, the runtime environment includes the interaction between clients executing Web browsers and Web servers, ERP Web Gateway, ERP Connector and ERP server. Access to the ERP server via the ERP Web Gateway is controlled by programming stored in strongly typed language files.
The process used in the runtime environment by the invention as shown in FIG. 3 is linked for the purpose of this explanation to the apparatus of the invention depicted in FIG. 2 by the use of Roman Numerals in both figures. Referring to FIGS. 2 and 3 the web browser on client 12 issues an object request (I). The object request is sent (II) from the web browser to the web server 14 . A web listener on the web server 14 receives the object request and examines it (III). The web listener launches a web agent (a servlet) in the ERP Web Gateway 16 (IV). The web agent invokes servlets to determine user ID, password, panel ID from the data contained in the object request, and an empty instance of the requested object is created (V). The newly created object obtains a connection to the ERP application through the ERP Connector 17 (VI). In turn the ERP Connector 17 communicates with the ERP application through the ERP Native Interface (VII).
(VIII) Data is passed in through the ERP Connector to the ERP application. The ERP application loads a panel using the data. (IX) The ERP application uses the panel to process data (a) to check data validity/relationship etc., and (b) to instruct the database manager to retrieve data based on data from the object request sent from the web browser to the web server. (XI) The database manager returns strongly typed data to the panel in the ERP application. The same data is returned back to the web agent through: (a) (XII) the ERP native API (weakly typed in the form of a string); and (b) (XIII) the ERP Connector API. The same data is returned to the web server (XIV) and then on to the web browser (XV).
According to the present invention, the development of Web applications for accessing relational databases may typically involve the following steps:
1. Create an ERP data definition that maps ERP data to strongly typed objects
2. Execute Code generation that extracts the ERP data definition and generates
a) Strongly typed program files;
b) Template output file;
c) HTML page containing commands to execute program files;
3. Optionally edit the template output file for a different ERP data output format.
4. Optionally edit the HTML page to either change the non ERP data in the web page or to change the sequence of access to the strongly typed objects.
5. Optionally edit the auto-generated or any human generated strongly typed language files.
6. Compile the strongly typed language files.
7. Install the template output file, HTML page and strongly typed language files in the ERP Web gateway.
The key challenge in writing applications for the ERP Web Gateway is to understand HTML, the ERP application, and the output template languages, since these languages are all involved in the ERP Web connector. In its simplest forms, basic knowledge of the ERP application and HTML can be easily acquired. However, these languages can be quite complex and tedious to write in order to utilize their advanced functions.
Fortunately, there are existing HTML editors that can help to greatly reduce the complexity of writing the HTML files. For example, NetObjects Fusion and Microsoft FrontPage provide user friendly environment to develop HTML files.
ERP Data Definitions (Data Access Code Generation)
Overview
Data access code generation to provide ERP Data Definitions is a process whereby a data object can be described using XML, and processed during build time to create the necessary Java classes, which provide access to the data in a database, the access to which is controlled by an ERP application at run-time. The advantages that this process has relative to the manual creation of the code include:
Simpler, straightforward set of XML elements can be used to describe the database (backend) attributes and the mapping to Java objects.
More maintainable and consistent generation of code, which is especially useful when there are several data objects to manage
Faster generation of data objects
Allows optimization of the code in the future, for example, lazy initialization
Allows retargeting objects for a different database or application
Users do not need to have knowledge of proprietary backend APIs
Allows generation of test suites
The overall data access code generation process is as follows:
1. Create an XML file describing the data object
2. Run a GenerateCode utility against the XML file created in the preceding step. The GenerateCode utility preferably applies code generation templates.
Data Object Description in XML
FIG. 4 shows the steps involved in using the code generator 92 to generate data access code 95 . First the author must use the data model that exists in the backend to create the data object description XML document 91 . All data object description documents must conform to a single DTD 90 which the Data Access Code Generator supports. The elements and attributes defined in the DTD 90 depend on the backend access APIs. For example, a system that accesses a relational database backend will contain attributes and elements for the columns names and the mapping of the columns to Java attributes.
A sample data object description XML for the Career object that retrieves data from the ps_acad_car_vw database table follows:
Career.xml—Sample data object description in XML
1<?xml version=“1.0”?>
<!DOCTYPE DOlist SYSTEM “DataObjectDescription.dtd”>
<!-- Career represents an academic career offered by an institution.
It corresponds to a row in the ACAD_CAREER table.
Career aggregates terms.
-->
<DataObject name=“Career” package=“com.ibm.pdc.common”>
<!-- Primary Key Attributes of the Career -->
<property name=“institution” key=“true”/>
<property name=“code” key=“true”/>
<!-- Attributes -->
<property name=“description”/>
<property name=“gradingScheme”/>
<!-- Mapping of Java attributes to database column names -->
<DatabaseAttributes table=“ps_acad_car_vw”>
<!-- keys -->
<input property=“institution” identifier=“INSTITUTION”/>
<input property=“code” identifier=“ACAD_CAREER”/>
<!-- data -->
<output property=“description” identifier=“DESCR”/>
<output property=“gradingScheme”
dentifier=“GRADING_SCHEME”/>
</DatabaseAttributes>
<!-- References -->
<ReferenceAttributes name=“terms” type=“Term” array=“true”>
<!-- Key specification -->
<key name=“institution” value=“institution”/>
<key name=“careerCode” value=“code”/>
</ReferenceAttributes>
</DataObject
The property elements specify the attributes of the Java class. The key attribute of the property element defines whether the property is a key. If an attribute is a key, the value of the attribute cannot be altered after the object is created. Key attributes are used to uniquely identify an object; the properties with key=“true” together form the primary key.
The DatabaseAttributes element contains the mapping of the Java attributes to the database column names. For each input and output tag within the DatabaseAttributes element, the author specifies the property and the identifier attributes. property contains the Java attribute name and identifier contains the backend identifier (a database column name in this example).
The ReferenceAttributes element describes an association relationship, which is implemented as a Java reference. For example, the ReferenceAttributes element is used to represent a foreign key relationship in a relational database. The elements within a ReferenceAttributes element contain the mapping of the attributes in the current object to the key (primary key or search key) attributes in the referenced object. ReferenceAttributes elements in the data object description are used to express a directed, labeled graph of objects, where each ReferenceAttribute element is a vector in the graph.
Data Object Data Type Definition (DTD) for data object description in XML
<!--
* DataObject.dtd is the DTD that all data object description files
must implement.
* ERP element - Element describing access to ERP panel
* DatabaseAttributes - Element describing access to database table
-->
<!ELEMENT DataObject (property?, ERPAttributes?,DatabaseAttributes?,
ReferenceAttributes?)*>
<!ATTLIST DataObject name CDATA #REQUIRED>
<!ATTLIST DataObject package CDATA #REQUIRED>
<!ELEMENT property EMPTY>
<!ATTLIST property name CDATA #REQUIRED>
<!ATTLIST property type CDATA #IMPLIED>
<!ATTLIST property key CDATA #IMPLIED>
<!ELEMENT ERPAttributes (input*,output*, subPanel*>>
<!ATTLIST ERPAttributes panelName CDATA #REQUIRED>
<!ELEMENT subPanel (input*, output*>>
<!ELEMENT DatabaseAttributes (input*,output*>>
<!ATTLIST DatabaseAttributes table CDATA #REQUIRED>
<!ELEMENT input EMPTY>
<!ATTLIST input property CDATA #REQUIRED>
<!ATTLIST input identifier CDATA #REQUIRED>
<!ELEMENT output EMPTY>
<!ATTLIST output property CDATA #REQUIRED>
<!ATTLIST output identifier CDATA #REQUIRED>
<!ELEMENT ReferenceAttributes (key*)>
<!ATTLIST ReferenceAttributes name CDATA #REQUIRED>
<!ATTLIST ReferenceAttributes type CDATA #REQUIRED>
<!ATTLIST ReferenceAttributes array CDATA #IMPLIED>
<!ELEMENT key EMPTY>
<!ATTLIST key name CDATA #REQUIRED>
<!ATTLIST key value CDATA #REQUIRED>
The above listing contains the DTD for the data object description shown in the Career.xml. In addition to DatabaseAttributes for accessing database attributes, the DTD also allows ERP Attributes for describing the access to ERP panels. ERP Attributes can contain an additional element called subPanel which is used to retrieve the attributes in a nested panel.
The Career object in the previous example can be retargeted to serialize information to/from ERP instead of the database by simply modifying the Career.xml data object description file. The DatabaseAttributes element will be replaced with an ERP Attributes element. Once Career.xml has been updated with the ERP Attributes element, rerunning the code generator routine will produce code that uses the ERP API to serialize the object instead of using JDBC to serialize to the database.
Code Generation Templates
The code generation templates 93 in FIG. 4 describe the code that is generated when the code generation routine 94 is invoked. The code generation routine 94 takes the code generation template 93 and the data object description XML 91 as inputs and produces Java source code 95 . The code generation template contains the following:
API calls for the backends that are supported in the DataObject.dtd. For the example in FIG. 2 , the code generation template will contain support for ERP API calls for accessing ERP and JDBC API calls for accessing relational databases.
Implementation of system-wide policies such as caching, lazy initialization, logging and use of system infrastructure.
Rules for code generation. For example, if a property is defined as a key, then only the getter method for the attributes is generated.
Describing a Sub-Graph of Data Objects for Improved Performance
The ReferenceAttribute elements can be used to describe a directed, labeled graph. Each data object description XML document is a node and the ReferenceAttribute elements are vectors of the graph. Each generated data object class typically performs lazy initialization. This approach is more efficient than populating the entire graph of objects, but it can result in several backend accesses.
For the object model in FIG. 9 , assume that data objects A, B and C need to be retrieved. The number of queries to retrieve data objects A, Band C using lazy initialization is as follows:
Number of queries to
retrieve objects
Number of objects returned
A
1 (find by primary key)
A
B
A
B
C
Ab
C
In general,
Number of backend accesses to retrieve object hierarchy (A->B->C . . . )=1+a+ab+abc . . .
where a, b, and c are the number of objects of class A, B, and C, respectively.
Therefore, the number of queries to retrieve an object hierarchy is proportional to the number of objects when lazy initialization is used.
In situations where there is considerable overhead for each access to the backend and the backend is efficient at performing joins, the overall systems performance can be improved by performing a single query that retrieves all the objects in the sub-graph of interest.
Sample Sub-Graph Description in XML
<DataObjectTree name=“CurrentEnrollmentsView”>
<rootnode name=“dataObjectA” dataobject=“A”>
<reference name=“dataObjectB” dataobject=“B”>
<reference name=“dataObjectC” dataobject=“C”/>
</reference>
</rootnode>
</DataObjectTree>
The sub-graph of the data model is described in an XML document, like the one shown above. The example describes a sub-graph for the CurrentEnrollmentsView business function that will retrieve data objects A, B and C using a single query. The example assumes that ReferenceAttribute elements from A to B and from B to C exist in the data object description XML documents for A and B respectively. Notice that data object D is not retrieved as part of this sub-graph.
The DataObjectTree element identifies the business function that this sub-graph or view of the model is for. Each rootnode element identifies a starting point of traversal of the object model. The rootnode elements contain reference elements to indicate that automatic pre-fetching of that reference is required. For example, <reference name=“dataObjectB” dataObject=“B”>, specifies that the reference from data object A to B should be retrieved as part of the single query. reference elements may be nested.
Using a code generation template that handles DataObjectTree documents, Java code can be generated to perform a single, large query that retrieves data objects A, B and C. The template will use the ReferenceAttribute element from A.xml, B.xml and C.xml to generate the correct join attributes for the single query.
The description of the data object in XML makes it possible to perform enhancements such as the use of sub-graphs for backend access optimization.
Using XML to describe data objects has several advantages. The users of the Data Access Code Generator need not learn the proprietary backend APIs, since the proprietary calls are contained only within the code generation template. The users of the code generator are then able to focus on leveraging their knowledge of the backend data model to create data access objects more efficiently. System-wide changes and enhancements can be made as part of a new build by regenerating the data objects using a modified code generation template or data object description. Using XML to describe the data object allows validation against the data object DTD to catch errors early in the development.
Conversion from ERP API to Strongly Typed Objects
FIG. 5 . is a flowchart illustrating the steps involved in invoking the ERP API and merging the results of that invocation into a strongly typed object. An example is the PeopleSoft Message Agent API (MAAPI). The MAAPI provides an API to access weakly typed PeopleSoft application data. The API provides methods for: specifying the panel to access, i.e. the CourseList panel; specifying the username and password for logging into the PeopleSoft application; methods for setting field values, i.e. setField (I); and methods for getting field values; i.e. getField (II). An example panel is the access to a list of courses that a student is taking (See FIG. 6 .). The student name and the term for the courses are known as search keys. There are many courses that may match a particular student name and term, so a course list object contains 1 student name, 1 term, and a list of courses. Each course may have multiple fields, such as course name and course number. The student and term are search keys located scroll level 0, and the list of courses are data found in scroll level 1. The list of courses has as many rows as there are courses. In other panels, there may be more than 2 levels of data.
The ERP API exposes the courses, student and term as fields. All the fields are returned in character type through the PS API. The API generalizes all Application data to fields with character values; hence losing the original context of the fields. This is known as weakly typed. It is often desirable to have the courses, student and term fields represented as courses, student and term respectively. In the Java programming language, this would involve the creation of a Java class called a studentCourseList 70 (see FIG. 15 7 .), that contains a student name 59 , and a list 60 of course objects. The course objects are instances of the Java class called course. Thus the objects are referred to as studentCourseList and courses, rather than fields, etc. This is known as strongly typed.
The algorithm for converting the weakly typed ERP Application data to strongly typed programming languages objects is:
1. Open a connection to the ERP API through the ERP Connector (description of the ERP Connector is included in the next section)
2. Set the Application object identifier, username and password using ERP Connector
3. Set any search key values (I)
4. Instruct the PeopleSoft application to process the current object
5. For every scroll level (level 0 and 1 in the example): (II)
5.1. Create object for the scroll level
5.1. for each row in the scroll level
5.1.1 if scroll level >0 then create new object in list
5.1.2 for each field in the row
5.1.2.1. get the field value (scroll level, row #, field #)
5.1.2.2. Set the strongly typed object value to field value
For example, if scroll level 0 and row level 0 and field 0 then set studentcourselist objects name attribute to field value
6. Close the connection to the ERP API through ERP Connector
ERP Connector (ERPC)
The ERP Connector insulates applications from the details of the underlying ERP applications. The ERP Connector API (ERP API), through which the ERP Connector is accessed, exposes objects that provide the ERP content and functionality required by the client Java objects. These connector objects will change only if there are significant semantic changes to the ERP system.
The ERP Connector is implemented as two distinct layers: the Application Connector and the Data Connector. The Application Connector implements the logical mapping of object data and behavior onto corresponding ERP application features. The Data Connector implements physical communication with the ERP system. The motivation for the separation of the Data and Application layers is the structure of a ERP system. The Data Connector is tightly coupled to a particular version of the ERP run-time environment and independent of the specific application being run. The Application Connector on the other hand, is tightly coupled to the underlying ERP application.
The ERP Connector provides the single point of access to the ERP application functionality. It does not extend the functionality of the ERP system. The Connector has detailed knowledge of the nature, purpose, and meaning of individual panels and data items, as well as of the business logic that applies to them. The Connector also knows the configuration of the underlying ERP system and how best to access specific items. The current interface is through the ERP API.
The ERP Connector will support multiple concurrent client requests through multi-threading. Clients connect to the Connector and make object requests using Connector API methods. There are no restrictions on the number of connections by a client, nor on the number of requests performed by a single connection. The Connector may limit the number of concurrent clients or requests by queuing new requests. During a connection, clients must specify the ERP identity that will be used to perform the requests. ERP uses this identity to control access to panels and database fields.
ERP Connector API
The ERP Connector APT is implemented by the Application Connector. The API provides both connection and application objects. Connection objects provide methods for establishing a connection and requesting specific application objects. Application objects provide specific functionality. Application objects may aggregate other application objects, and may be collections, with the caveat that updates that involve multiple panels may not execute atomically. The full API is not specified at this time because it depends on requirements and restrictions that are to be identified during product development.
Basic application objects consist of attributes that correspond to data values, and methods that correspond to actions that apply to the object. The methods a particular application object provides will vary, but certain ones are likely to be standard. These include the Get(field) method which populates the object attributes from the ERP application for a particular instance as specified by a set of key values passed to Get(field) as parameters. The complementary Set(field) method persists the current attribute values to the ERP backend. Other standard methods include Add( ), Delete( ), and VerifyValues( ). The later method verifies the acceptability of the current attributes against the edit checks and business logic defined for this object in the backend, but does not persist the values. In addition to the standard set, a particular object may have any number of specific methods that correspond to special behavior for that object.
Although the Connector APT is described as a local Java object, performance consideration may require that the Connector exists on a remote computer. In this case, the API may be modified for remote invocation through a mechanism such as Java RMI or CORBA.
The Connector APT is a synchronous interface with no callbacks or events. This reflects the functionality of the API.
An outline of the ERP Connector APT is shown below:
package com.ibm.studentserver.ERP.connector;
static class ERPConnector // Singleton
{
ERPConnection Connect( String operatorID; String password)
throws ConnectException;
}
class ERPConnection
{
private final String operatorID;
private final String password;
void Disconnect( );
// other methods
}
II Application classes
class CourseDescription
{
// Attributes
String courseId;
String name;
String description;
// Methods
static CourseDescription Get( String courseld ) throws ... { };
void Se( )throws { };
void Add( String courseld )throws ... { };
void Delet( )throws ... { };
...
}
ERP Data Connector API
The Data Connector interface is based on the concept of a message definition, which is a named specification of a ERP panel and the mapping of data fields to panel fields. The Data Connector provides a Connection object that establishes an authenticated connection with the ERP system. Through a Connection object, the client obtains Message objects that provide methods for manipulating the panel contents. An outline of the Connector follows:
Package com.ibm.studentserver.ERP.MAConnector;
static class MAConnector // Singleton
{
MAConnection connect( String operatorID; String password)
throws ConnectException;
}
class MAConnection
{
private final String operatorID;
private final String password;
disconnect( ) { };
Message startMessage( String name) { };
}
class Message
{
processMessage( ) { };
II Meta information
getFieldCoun( ) { };
getFieldLis( ) { };
// Input
s=SetField( String name, String value) { };
// Output
findFirstFiel( ) { };
// Others
}
ERP Message Agent Background:
The ERP Message Agent is the designated method by which external applications can get information in and out of an ERP application. The Message Agent API enables external programs to operate ERP panels programmatically. The program can read and set the values of all panel controls including multi-level scrollbars, as well as “press” buttons on the panels. The panel is not aware that a program is operating on it; thus, it performs all regular actions: checking security, executing PeopleCode attached to record fields, workflow actions.
The Message Agent API consists of about fifty C language functions and several supporting libraries that can be invoked using the Java Native Interface (JNI). Before a panel can be used by the message agent, a named “message definition” must be created using appropriate tools available for the ERP. The message definition specifies the panel name, action mode, search record definition, and panel field-mapping through which the program gets at the panel data. The API provides functions to:
Establish and end a session, which may process multiple messages
Set the operator id to be used for the session
Deal with search dialogs
Report errors
Access all the types of data fields on a form.
Converting Strongly Typed Object Language to Strongly Typed Declarative Language
The strongly typed object language is converted to a strongly typed declarative language by looping over the contents of the strongly typed object and creating a declarative object for each object value.
Using the previous example of the studentCourseList, a sample XML output is:
<StudentCourseList>
<StudentName>John Smith</StudentName>
<CourseList>
<Course><Name>Math</Name><Number>100-
</Number></Course>
<Course><Name>English</Name><Number>101-
</Number></Course>
</CourseList>
</StudentCourseList>
To take advantage of the emerging XML tools, it is necessary to describe the ERP data in XML. Describing ERP data in XML provides an industry standard interface for accessing ERP functions without requiring modification to the ERP database.
The XML data file for ERP Message Agent results is created by converting the Message Agent C output into XML text data. The first step is to call the C API for each Message Agent row result, and store the values into a structure. Then the structure results are converted to a well-formed XML stream.
A sample of this is a ERP Course List panel. It produces a tabular column of courses, consisting of course name, and other course information.
The Message Agent C API is called to retrieve the course rows from the panel and store them into a structure. A sample of the structures in Java is:
public class Course
{
private String name;
private String number;
public String getName( )
{
return name;
}
public void setName(String theName)
{
narne = theName;
}
public String getNumber( )
{
}
return number;
}
public void setNumber(String aNumber)
{
number = aNumber;
}
}
// StudentCourseList is a Java object representing ERP panel
public class StudentCourseList
{
// courseList is a collection of courses
private java.Collections.List courseList;
private String studentName;
public String getStudentName( )
{
return studentName;
}
public void setStudentName(String aStudentName)
{
studentName = aStudentName;
}
public java.Collections.List getCourseList ( )
{
return courseList( )
}
// build a course list of course object
.......
.......
}
The Java objects are serialized into XML using a serialization routine. No matter the specific mechanism, the approach is that each item in the list is serialized as an XML fragment. Each XML fragment contains an XML element corresponding to the properties of the object, which are the elements (i.e. text field, radio button field, Y/N field etc.) on the ERP Panel.
The output of the serialization is a list of Courses, for example:
<StudentCourseList>
<StudentName>StudentName</StudentName>
<Course>
<Name>Course#1</Name>
<Number>Number#1</Number>
</Course>
<Course>...</Course>
</StudentCourseList>
The XML returned from two or more panel objects can be merged to create a unified view of the data in ERP. For example, as supplied by ERP, information about the meeting time and name of the instructor of a course are provided on different panels. The XML streams from the two panels can be merged to present all the information about a course on a single web page.
Sending ERP API Data to Web Clients
FIG. 8 . is a flowchart illustrating the steps involved in invoking the strongly typed objects, and converting the strongly typed objects into a format requested by the web client.
1. Browser issues HTTP request.
2. Web server receives HTTP request.
3. Web server determines that ERP Web Gateway instance needed.
4. Web server creates ERP Web Gateway instance.
5. ERP Web Gateway receives parameters from HTTP request and HTML page containing reference to ERP Web Gateway.
6. ERP Web Gateway creates strongly typed objects using the Java class corresponding to requested ERP application object data.
7. ERP Web Gateway obtains data from the ERP Application through the ERP Connector.
8. ERP Web Gateway determines requested output format from parameters.
9. ERP Web Gateway formats strongly typed object to:
XSL
9.1 If XSL
9.1.1 Read XSL template
9.1.2 Convert strongly typed objects to strongly typed declarative language (XML)
9.1.3 Apply XSL template to declarative language objects
9.2 if Strongly Typed Object template
9.2.1 Read Strongly typed object template
9.2.2 Apply template that converts strongly typed object language to HTML XML
9.3 If XML
9.3.1 Convert strongly typed objects to strongly typed declarative language object
10. ERP Web gateway returns ERP data in requested output format to Web server
11. Web server returns data to Web browser
Conclusion
This concludes the description of the preferred embodiment of the invention. The following describes some alternative embodiments for accomplishing the present invention. For example, any type of computer, such as a mainframe, minicomputer, or personal computer, could be used with the present invention. In addition, any software program adhering (either partially or entirely) to the HTTP protocol or the HTML or ERP Application that exposes a set of external API could benefit from the present invention.
In summary, the present invention discloses a method and apparatus for accessing and updating ERP Application data via the World Wide Web of the Internet. In accordance with the present invention, Web users can request information from ERP Applications via HTML input forms, which request is then used to interact with the ERP Application. The results output by the ERP Application are themselves transformed into HTML format for presentation to the Web user.
The foregoing description of the preferred embodiment of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto. | A method of converting ERP data in a database managed by an ERP application and accessed through an ERP API and ERP Message Agent API (MAAPI) to strongly typed data in Java objects includes steps of reading, parsing, creating, and populating. A XML file containing the definition of the Java objects and their attributes of HyperText Markup Language (HTML) statements which specifies presentation format is read. Each of the declarations and HTML statements are parsed to identify definitions of objects and their attributes. The respective objects are created with their attributes. The objects are populated with data from the ERP data. | 8 |
CROSS-REFERENCE
[0001] This application claims the priority filing date of U.S. Provisional Application Ser. No. 61/462,804 filed Feb. 8, 2011, herein fully incorporated by reference.
FIELD OF THE INVENTION
[0002] Nanoparticles of various metal cyanide compounds containing manganese(II) ions in the crystal lattice having very low release of free Mn 2+ ions, very low cyanide toxicity and high relaxivity values are suitable as MRI contrast agents. The nanoparticles are surface modified with a water-soluble and biocompatible polymer, have long blood circulation half lives, and can be used at low concentrations with low- and high-magnetic field scanners to enhance magnetic resonance imaging (MRI) contrast.
BACKGROUND OF THE INVENTION
[0003] From the entire periodic table, there are only a few elements with a stable and biocompatible oxidation state and a high number of unpaired electrons that are considered suitable for image enhancement applications in magnetic resonance imaging (MRI). These include Mn(II) (HS; S=5/2), Fe(III) (HS; S=5/2) and Gd(III) (S=7/2). The MRI signal intensity (SI) from different body tissues varies with the content of water protons present in the tissue and with both the longitudinal (T 1 ) and transverse (T 2 ) relaxation times of those protons. In some cases, the variation of water content in different tissues is sufficient to produce image contrast. In other cases, it is necessary to use a contrast agent to enhance the image contrast. Chemical compounds that can change the relaxation times, either T 1 or T 2 , within a tissue are routinely used as contrast agents in MRI in the medical diagnosis of diseases and/or organ functions in the human body.
[0004] Clinical MRI contrast agents can be divided into two classes, T 1 agents and T 2 agents. A T 1 or positive contrast agent shortens the longitudinal relaxation time (T 1 ) of water protons, and can brighten regions where the agent is present. Conversely, a T 2 or negative contrast agent reduces the transverse relaxation time (T 2 ) of water protons, and produces darkened spots in the tissues reached by the agent when a residual transverse magnetization is used in a spin-echo experiment.
[0005] The majority of the T 1 contrast agents have been developed from the use of the paramagnetic Gd 3+ ion chelated by various low molecular weight polyaminopolycarboxylate ligands. The high electronic spin (4f 7 , S=7/2, 7.9 BM), coupled with a symmetric electronic ground state ( 8 S 7/2 ) and slow electronic relaxation (10 −9 s), gives Gd(III) unique nuclear-magnetic properties for enhancing T 1 -relaxation of protons from bulk water. Currently, there are nine commercial T 1 agents approved worldwide for clinical use ( FIG. 1 and Table 1).
[0006] The major drawback of these agents is their limited sensitivity (relaxivity). The relaxivity of a contrast agent is the measure of its efficacy and usually expressed as the concentration-normalized amount of increase in the longitudinal relaxation rate 1/T 1 per millimole of agent in the unit of mM −1 ×s −1 . As a result, MR imaging applications using such agents require high tissue concentrations (0.1-0.6 mM). Relaxivity of these agents drops significantly at higher magnetic fields, which makes them inefficient in the high-field MR scanners for clinical diagnostic imaging. The high-field scanners can greatly shorten data acquisition time, improve signal-to-noise ratio (SNR) and provide higher spatial resolution. Recently, the use of the Gd 3+ -based MRI contrast agents has been linked to nephrogenic systemic fibrosis (NSF), an acute and fatal toxic adverse reaction in patients with impaired renal function. NSF is believed to be caused by the in vivo release of the Gd 3+ ions from the chelates. The toxicity of gadolinium stems from the fact that the ionic radius of Gd(III) (1.02 Å) is very similar to that of calcium(II) (1.00 Å). Hence, the presence of this heavy metal ion in the body can disrupt the normal functions of many types of voltage-gated Ca 2+ -channels at the nano- to micro-molar concentration level. In addition to toxicity, due to the lack of ability to penetrate cells, these small molecule-based T 1 contrast agents function only as extracellular agents, which limits their use in detecting biological receptors or markers within the cell and makes them ineffective as cellular MR probes.
[0000]
TABLE 1
Stability constants and relaxivity values
for the commercial MRI contrast agents
Trademark
LogK GdL
r 1 (mM −1 × s −1 )
Dotarem ®
25.3
4.2
ProHance ®
23.8
4.4
Gadovist ®
20.8
5.3
Magnevist ®
22.2
4.3
Omniscan ®
16.8
4.6
OptiMARK
16.8
5.2
MultiHance
18.4
6.7
Primovist
23.5
7.3
Vasovist
23.2
19
[0007] All the existing T 2 contrast agents are based on superparamagnetic iron oxide nanoparticles (SPIOs). These agents shorten the transverse relaxation time (T 2 ) of bulk water to produce a negative or darkened contrast. Although SPIOs are nontoxic and FDA-approved contrast agents with higher sensitivity and can penetrate cells, from the standpoint of clinical diagnosis and cellular imaging, the image contrast produced by such agents is far less desirable than that by the T 1 agents. It is difficult to distinguish between the darkened spots produced by the accumulation of a T 2 agent and the signals caused by bleeding, calcification, metal deposit, or other artifacts from the background. This fact can complicate the correct interpretation of imaging results, and is a major barrier for T 2 agents to gain widespread clinical applications in replacement of T 1 agents. Besides this, imaging with T 2 contrast requires longer acquisition times. Currently, the primary application of SPIOs T 2 agents is for image-guided drug delivery and the monitoring of surgical procedures.
[0008] Besides the Gd 3+ ion of seven unpaired electrons, the next highest possible number of unpaired electrons is five (S=5/2). The electron configuration corresponding to this spin state is found in the stable transition metal ions Fe(III) and Mn(II). Although iron is an essential element in biology, the use of analogous Fe 3+ -chelates to deliver Fe(III) for T 1 MRI contrast is deemed unacceptable due to the high cellular toxicity of this metal. Because most high-spin Fe(III) complexes have low to modest thermodynamic stability and are kinetically labile, in vivo release of free Fe 3+ ions from such chelates is inevitable. As the result, any Fe 3+ -containing compound administered parenterally can disturb the iron homeostasis that is tightly regulated by ferritin and transferrin receptors in the body. The ferrous ion Fe 2+ , produced from any non-sequestered ferric ion through reduction by a variety of biomolecules, can catalyze the generation of reactive oxygen species (ROS) including hydroxyl radical and peroxide radical via the so-called Fenton chemistry:
[0000] Fe 2+ +H 2 O 2 →Fe 3+ +OH.+OH − (1)
[0000] Fe 3+ +H 2 O 2 →Fe 2+ +OOH.+H + (2)
[0009] The above ROS species can lead to wide-spread systemic injury to the liver, heart and endocrine organs as well as increases in infection. To avoid the Fe 3+ or Fe 2+ ions to be leached into the body, completely insoluble iron compounds in the form of superparamagnetic iron oxide nanoparticles (SPIOs of Fe 3 O 4 or γ-Fe 2 O 3 ) have been developed as T 2 MRI contrast agents (vide supra).
[0010] An FDA approved Mn 2+ -based small-molecule complex has been developed as a MRI contrast agent, namely manganese dipyridoxal diphosphate (MnDPDP) for application to liver, pancreas, and heart. However, the Mn 2+ is shown to be released in vivo due to the transmetallation with zinc(II). Therefore, the contrast enhancement detected in these organs is due to the presence of the released paramagnetic Mn 2+ ions. The cellular toxicity of higher level manganese (>1 mM) has prevented any Mn 2+ -complex from being developed as the generalized MRI contrast agent. It is well known that exposure to high concentration level of Mn 2+ can lead to neurological deficits, particularly a neurological disorder resembling Parkinson's disease.
SUMMARY OF THE INVENTION
[0011] This invention describes a synthetic procedure for preparing nanoparticles from a class of metal cyanide compounds whose surfaces are coated with a water-soluble and biocompatible polymer. Such nanoparticles have long blood circulation half lives, very low release of free Mn +2 ions, very low cyanide toxicity, high relaxivity values and can be used at low and high magnetic fields as non-gadolinium containing MRI contrast agents.
[0012] A contrast agent composition, comprising a plurality of nanoparticles having the formula A x Mn y [M(CN) 6 ] z .nH 2 O where A=Li, Na, K, NH 4 or Tl; M=Cr, Mn, Fe, Co or Ru; x=0-2; y=1-4; z=1-4; and n=0 or 1-20, said nanoparticles adaptable for use as a MRI contrast agent.
[0013] A maganese(II) hexacyanometallate composition, comprising manganese(II) hexacyanometallate nanoparticles having a faced-centered cubic structure (space group Fm3 m ) and having the unit cell parameter a=10±1 angstroms and are adaptable for use as an MRI T 1 contrast agent; and water.
[0014] A process for preparing a manganese(II) contrast agent composition, comprising the steps of: treating a hexacyanometallate with a H-form ion exchange resin and then mixing with manganese chloride and an organic amine or an alkali metal hydroxide or carbonate and forming a manganese(II) contrast agent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 relates to schematic structures of common MR contrast agents with one coordinated water molecule omitted from each structure for clarity;
[0016] FIG. 2 is the crystal structure of KMn[Fe III (CN)6];
[0017] FIG. 3 is a diagram showing the Mn 2+ ion leaching results under different pH conditions;
[0018] FIG. 4 shows the proton T 1 (top) and T 2 (bottom) relaxation rate versus concentration of Mn 2+ ion at 11.7 T; and
[0019] FIG. 5 shows the proton T 1 (top) and T 2 (bottom) relaxation rate versus concentration of Mn 2+ ion at 7.0 T.
DETAILED DESCRIPTION OF THE INVENTION
[0020] According to the concepts of the present invention, various nanosized particles containing manganese(II) ions in the crystal lattice have been developed for use as MRI contrast agents. More specifically, the contrast agents are manganese (II) hexacyanoferrate compounds having the formulas Mn 2 [Fe II (CN) 6 ], A 2 Mn 3 [Fe II (CN) 6 ] 2 .nH 2 O, AMn[Fe III (CN) 6 ].nH 2 O where A=Li, Na, K, NH 4 or Tl and Mn 3 [Fe III (CN) 6 ] 2 .nH 2 O where n=0 or 1-20. The compounds generally have the same crystal structure, that is a faced-centered cubic lattice (space group Fm 3 m) and the unit cell parameter a=10±1 angstroms as set forth in FIG. 2 .
[0021] Referring to FIG. 2 , due to the strong ligand-field effect and simultaneous coordination of the CN − group to both iron and manganese ions in this extended 3D coordination network structure, both metal ions and CN − ligand are completely locked in the lattice positions and generally cannot be released from the compound. A result is that very low amounts of Mn 2+ ions are released and thus the compounds there are considered stable and have very low toxicity. It has also been found that such compounds have a long blood circulation half life that allows a longer time window for imaging studies. Blood circulation half lives of the contrast agents of the present invention generally range from about 0.1 to 2 hours, desirably from about 0.25 to about 2.0 hours and preferably from about 0.5 to about 2.0 hours. Moreover, the concentrations of the manganese contrast agents in water that can be utilized for application to an animal such as a human being for an MRI analysis are amounts generally from about 1 micromole to about 150 millimoles, desirably from about 10 micromolar to about 100 millimolar and preferably from about 25 micromolar to about 50 millimolar per liter of solution.
[0022] The manganese(II) hexacyanometallate nanoparticles are made using conventional methods known to the art and to the literature, having diameters generally from about 4 to about 500 nm, desirably from about 6 to about 200 nm and preferably from about 8 to about 100 nm. The particle diameter size is important in that it results in long circulation times in the blood stream before it is removed by the body. In contrast thereto, very small diameter sizes such as less than 2 nm or less than 1 nm are avoided since they are readily removed from the human body and have a short residence time therein, for example less than 20 minutes that is unacceptable for use as a MRI contrast agent.
[0023] The manganese contrast agents of the present invention are adapted to be applied to the body as dispersed nanoparticles in a solvent such as water stabilized by a hydrophilic coating comprising a carboxylic acid or a hydrophilic biocompatible polymer, or both. The hydrophilic coating acts to make the otherwise insoluble manganese(II) nanoparticles dispersible in water, and thus promoting water stability of such nanoparticles while providing a protection shell against nanoparticle aggregation and precipitation. Suitable carboxylic acids include, but are not limited to, common carboxylic acids such as acetic acid, oxalic acid, citric acid, tartaric acid, adipic acid, gluconic acid, and other mono-, di-, tri- or polycarboxylic acids. Suitable hydrophilic biocompatible polymer used for coating to prolong blood circulation times, reduced biological toxicity, and particle solution stability against aggregation and precipitation include, but are not limited to, polyethylene glycol (PEG), chitosan, dextran, e.g., polymers of glucose having number average molecular weights up to 200,000, and polyvinylpyrrolidone (PVP).
[0024] The manganese contrast agent aqueous solutions are generally stable in acidic to neutral solutions with a pH value from about 1 to about 7.5, desirably from about 2.5 to about 7.5, and preferably from about 3.5 to about 7.3.
[0025] A general procedure for preparation of nanoparticulate Mn 2 [Fe(CN) 6 ] MRI contrast agents comprises the following reactions:
[0000] K 4 [Fe(CN) 6 ]+H-form ion exchange resin→H 4 [Fe(CN) 6 ]
[0000] 2MnCl 2 +H 4 [Fe(CN) 6 ]+triethylamine→Mn 2 [Fe(CN) 6 ]
[0026] Generally any type of known H-form ion exchange resin can be used with suitable examples including AMBERLITE™ IR120 H from Dow Chemical Company, a styrene divinylbenzene copolymer with sulfonic acid groups, AG 50W-X2 from Bio-Rad, a cation exchange resin, and AMBERLYST™ 16 West from Rohm and Hass, a sulfonic acid ion exchange resin.
[0027] With respect to the second part of the contrast agent preparation utilizing an amine, generally the suitable organic amine compounds include, but not limited to, amines having from 3 to about 12, and desirably from 3 to about 10 carbon atoms such as triethylamine, benzylamine, ethylenediamine, piperidine, pyridine, pyrazine, 2,2′-bipyridine and 4,4′-bipyridine, or any combination thereof. Alternatively, an alkali metal hydroxide AOH or alkali metal carbonate A 2 CO 3 where A=Li, Na, K, Rb or Cs can be used in the place of the organic amine.
[0028] The manganese(II) contrast agents of the present invention can be prepared as follows:
[0029] A proper concentration, i.e. 10 −3 to 10 3 M, of K 4 [Fe(CN) 6 ] was first treated with a proper amount of H-form ion exchange resin, i.e. about 1 gram to about 1,000 grams and desirably from about 5 to about 500 grams, to yield H 4 [Fe(CN) 6 ] that was then mixed with a proper concentration, i.e. 10 −3 to 10 3 M and desirably from about 0.01 to about 1.00 M of MnCl 2 in the presence of a proper amount of triethylamine, i.e. 0.01 gram to 10 grams and desirably from about 0.05 to about 5.00 grams, citric acid, i.e. 0.01 gram to 10 grams, and desirably from about 0.01 to about 3.00 grams, and PVP, i.e. 0.01 gram to 10 grams and desirably from about 0.03 to about 8.00 grams, to form nanoparticles of Mn 2 [Fe(CN) 6 ] with the size ranging from 4 to about 500 nm and desirably from about 8 to about 100 nm, depending on the ratio of the reacting components. Simple reaction temperatures of the first reaction range from about 0 to about 100° C. and desirably from about 5 to about 95° C. The reaction temperature with respect to the second reaction generally range from about 0 to about 100° C. and desirably from about 5 to about 95° C. The reaction conditions are generally limited by the freezing point and boiling point of water.
[0030] When other manganese contrast agents other than Mn 2 [Fe(CN) 6 ] are desired, the process is essentially similar except that the ratios of the above noted compounds are changed. For example, if Mn 3 [Fe III (CN) 6 ] 2 is desired, a proper concentration, i.e. 10 −3 to 10 3 M of K 3 [Fe(CN) 6 ] can be treated with a proper amount of H-form ion exchange resin and allowed to react with a proper concentration, i.e. 10 −3 to 10 3 M and desirably from about 0.01 to about 1.00 M, of MnCl 2 in the molar ratio of K 3 [Fe(CN) 6 ]:MnCl 2 to be 2:3 while all the other conditions are kept exactly the same as described in [0028]
[0031] In order to determine the release rate of the Mn 2+ ions of the manganese(II) hexacyanometallate contrast agents of the present invention, nanoparticles of the formula Mn 2 [Fe(CN) 6 ], were treated with 20 parts of a saline solution, e.g. a NaCl solution having a pH of 1, 3, 5, and 7 and incubated at room temperatures for 16 hours. The potential transmetallation reactions between the nanoparticles and solutions each containing the following ions: 1 mM Ca 2+ , 1 mM Mg 2+ , 1 mM K + or 1 mM Zn 2+ ions were also studied. The results were analyzed by Atomic Adsorption (AA) and showed that the highest Mn concentration found has ˜19 ppm, which is much less than the minimal toxic level of 0.1 mM, see FIG. 3 .
[0032] As apparent from FIG. 3 , the Mn 2+ release amounts were higher at lower pH levels and essentially nil when utilized with magnesium and calcium ions. Moreover, the release rate of the Maganese(II) hexacyanoferrate with respect to Mn 2+ is approximately 2,000 times less than the release rate of MnDPDP. Thus, release rates of at least about 25, about 50, about 100, about 500, or about 1,000 times less than the release rate of MnDPDP can be readily obtained. Stated in other words, the in vitro release rate of Mn 2+ at a pH of about 7 is from about 10 to about 20, desirably from about 12 to 18, and preferably from about 14 to about 16 parts per million in water for a 24 hour time period. FIG. 3 also shows that the release rate of manganese in the presence of other ions at a pH of 7 such as zinc, magnesium, and calcium was also extremely low.
[0033] The concentrations of free cyanide ions released from manganese(II) hexacyanoferrate MRI contrast agents of the present invention is generally at the level of ˜10 ppm, which is about 10 to 15 times less than a minimum toxic level of 0.1 mM currently set forth by the EPA. That is, the in vitro concentration of free cyanide ions released by the MRI contrast agents of the present invention is generally about 2 to about 50, and desirably from about 5 to about 30 times less than the current minimum toxic EPA level of 0.1 mM of free CN − ions. These values are determined based upon the release rate of free cyanide ions in water during a 24 hour time period at room temperature, e.g. about 65 to about 85° F. The manganese contrast agents of the present invention thus essentially have no toxicity and are very safe for use in MRI scanning.
[0034] A series of proton T 1 and T 2 relaxation measurements using 500 MHz (11.7 T) NMR were made. The results expressed as the concentration-normalized relaxivity values are r 1 =7.3 mM −1 ×s −1 and r 2 =204 mM −1 ×s −1 per mM of Mn 2+ ions, see FIG. 4 . These values are among the highest measured relaxivity values ever obtained for any MRI contrast agent.
[0035] Solutions of various concentrations of Mn 2 [Fe(CN) 6 ] nanoparticles were used for T 1 and T 2
[0036] Measurements using a 7.0 T MRI scanner. For T 1 measurements, an inversion recovery gradient echo sequence with a TE=4 ms was used. The inversion time was varied between 30-2000 ms. T 2 measurements were performed using a spin-echo sequence of TR of 10000 ms, and TE of 10.6-340 ms, see FIG. 5 . The results expressed as the concentration-normalized relaxivity values from these measurements are r 1 =6.07 mM −1 ×s −1 and r 2 =117 mM −1 ×s −1 per mM of Mn 2+ ions. These results further confirmed that Mn 2 [Fe(CN) 6 ] nanoparticles possess have relaxivity values at a medically relevant high magnetic field of 7.0 Tesla.
[0037] The in vitro T 1 (positive contrast values) of the MRI contrast agents of the present invention have relaxivity values, i.e. r 1 , of from about 1 to about 15, desirably from about 2 to about 15, and preferably from about 4 or about 6 to about 14 mM −1 ·s −1 /mM of Mn +2 ions. The T 2 (negative contrast agents) of in vitro relaxivity values, i.e. r 2 , is from about 50 to about 300, desirably from about 170 to about 250, and preferably from about 100 to about 200 mM −1 ·s −1 /mM of Mn +2 ions.
[0038] Another advantage of the present invention is that the manganese MRI contrast agents can be utilized in either high or low magnetic field strength such as from about 0.5 to about 11 Tesla and desirably from about 1.0 to about 9.0 Teslas.
[0039] The manganese contrast agents of the present invention can be utilized where ever MRI contrast agents have been utilized heretofore and the same is well known to the art and to the literature including the administration thereof. The contrast agent can be utilized with respect to various animals including pets such as dogs, cats, horses, cattle, pigs, goats, chickens, turkeys, etc. A highly preferred end use is for MRI diagnosis of human beings, i.e. persons, as by various well known methods such as oral administration, intravenous injection, and the like.
[0040] While in accordance with the patent statutes the best mode and preferred embodiment have been set forth, the scope of the invention is not intended to be limited thereto, but only by the scope of the attached claims. | This invention discloses a synthetic procedure for preparing nanoparticulate materials of various metal cyanide compounds containing manganese(II) ions in the crystal lattice with the surfaces coated by a hydrophilic compound, and their use as MRI contrast agents with high sensitivity, long blood circulation half lives and low toxicity at low-field and high field MR scanners. | 0 |
RELATED APPLICATIONS
[0001] This application claims the benefit of provisional U.S. Patent Application Serial No. 60/040,249 filed Feb. 11, 1997.
FIELD OF THE INVENTION
[0002] The present invention relates generally to packet-switching communication systems, e.g., ATM (Asynchronous Transfer Mode), and particularly, to schemes for shaping traffic in ATM and packet data switches.
BACKGROUND OF THE INVENTION
[0003] ATM switches are beginning to make an appearance in service provider's networks. However, the networking technology of choice for end-users remains packet-switching technology, including, for example, IP/Frame relay (FR) packets, IPX and ATM FUNI, and TCP (UDP)/IP(IP) among others due to the slow penetration of native ATM to desktops. This implies that enterprise switches in the near future will need to provide FR and IP interfaces on the premises side and ATM connectivity on the wide-area network (WAN) side.
[0004] [0004]FIG. 1 illustrates an enterprise switch 10 with IP packet or frame relay traffic 20 being multiplexed with native ATM traffic 25 onto a wide-area links. Particularly, at the FR/IP interface card 22 , a segmentation process is performed in the ATM adaption layer (AAL) whereby IP and/or frame relay (FR) packets (collectively “Packets”) are converted to ATM cells. Particularly, as shown in FIGS. 2 ( a ) and 2 ( b ) the segmentation process involves converting FR packets 20 a, b, c into corresponding one or more ATM cells 30 a, b, c, respectively, in accordance with well known SAR (segmentation and reassembly) techniques. In such a configuration, for example, a 1500 byte FR Packet generates 30 ATM cells, instantaneously, with each ATM cell having about 53 bytes. As shown in FIG. 1, these ATM cells are transported through the ATM switch fabric 32 at the switch port rate to the egress port queue 35 of ATM output card 40 . Since the switch port speed can be orders of magnitude larger than the egress port rate, the ATM cells 30 arrive at a very high rate relative to the port queue service rate. That is, the instantaneous rate of arrival of ATM cells at the egress port queue 35 is substantially greater than the output speed at the wide-area WAN egress link 50 , e.g., a T- 1 link, resulting in queue buildup and cell losses which have a serious performance impact on the ATM and non-ATM traffic. For example, there may be difficulties in meeting the cell loss and other Quality-Of-Service (QoS) guarantees for the ATM services, and large Packet losses for the non-ATM traffic since single ATM cell losses cause loss of entire packets. While one could account for this high-rate burst in the ATM connection admission control (CAC) mechanism, it would be prohibitively expensive in terms of the bandwidth required to prevent e.g., cell loss.
[0005] It would thus be desirable to shape the ATM cells resulting from the segmentation of packets in order to smooth the ATM cell bursts at the switch outputs and reduce their congestion impact.
SUMMARY OF THE INVENTION
[0006] The invention is a packet traffic shaping scheme for one or more streams of packet traffic sharing a common resource, e.g., an output egress link in a packet switching device. A first stream of delay tolerant packets, e.g. IP/frame-based packets, are multiplexed to a second stream of packets, e.g. native ATM cells having to meet QoS guarantees. Particularly, the invention provides for the dynamic shaping of the first stream of traffic that is effective in limiting the FR and IP packet loss and the ATM cell loss at the expense of some additional delays for FR and IP traffic which additional delays are acceptable for the packet traffic.
[0007] One aspect of the invention is to provide, in an ATM interface switch, an open-loop shaping scheme that shapes traffic “constantly” regardless of the congestion on the WAN egress link. Another aspect of the invention is a closed-loop shaping scheme whereby the FR and IP traffic is shaped only when there is congestion on the egress hnk. This closed-loop scheme provides superior performance to the first since shaping only takes place when it is needed.
[0008] The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, and specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
BRIEF DESCRIPTION OF DRAWINGS
[0009] [0009]FIG. 1 is a general diagram illustrating an ATM switch capable of multiplexing native ATM cell and IP/FR data.
[0010] [0010]FIG. 2 is a diagram illustrating segmentation of IP and/or FR Packets data into ATM cells.
[0011] [0011]FIG. 3( a ) illustrates a traffic shaping scheme of the first embodiment of the invention.
[0012] [0012]FIG. 3( b ) illustrates a variation of the traffic shaping scheme of the first embodiment of the invention.
[0013] [0013]FIG. 4 illustrates the circuit implementation of a traffic shaping scheme of the second embodiment of the invention.
[0014] [0014]FIG. 5 illustrates ATM cell traffic transmission as governed by the shaping scheme of the second embodiment of the invention.
[0015] [0015]FIG. 6 illustrates a variation of egress buffer queue thresholding technique implemented by the shaping scheme of the second embodiment of the invention.
[0016] [0016]FIG. 7( a ) illustrates a plot of Stop/Go shaping loss rates versus stop thresholds.
[0017] [0017]FIG. 7( b ) illustrates a plot of Frame delay versus stop thresholds.
[0018] [0018]FIG. 8( a ) illustrates a plot of shaping method performance impact on FR packet loss rates.
[0019] [0019]FIG. 8( b ) illustrates a plot of shaping method performance impact on FR delay.
[0020] [0020]FIG. 9 illustrates a plot of the ATM Cell loss rate for different shaping methods.
DETAILED DESCRIPTION OF THE INVENTION
[0021] As packet traffic does not have any binding QoS guarantees, or, have only loosely defined QoS guarantees, this traffic is shaped to reduce the performance impact of large high-rate bursts. This shaping implies that ATM and non-ATM cell loss could be reduced at the expense of some additional delays for the packet traffic.
[0022] [0022]FIG. 3( a ) illustrates the result of an open-loop ATM traffic shaping scheme that is blind to congestion on the WAN egress link. In this embodiment, SAR mechanisms are implemented at the FR/IP Interface card 22 (FIG. 1) to shape the output ATM cell traffic to conform to a given peak cell-rate (PCR), i.e., just enforce a minimum spacing between output ATM cells. Thus, as shown in FIG. 3( a ) ATM cells 30 are output with a spacing of 1/PCR and may be implemented by commercially available SAR (segmentation and reassembly) chips, e.g., the Bt8230 provided by provided by Brooktree Corp. As is known, such SAR chips are already employed in ATM cell rate policing, e.g., the so-called “leaky bucket” policing.
[0023] In accordance with the principles of the invention, a variation of the first embodiment is an open-loop ATM traffic shaping scheme that shapes ATM cell traffic to conform to a given peak cell-rate (PCR) and sustainable cell-rate (SCR). The PCR/SCR shaping imposes two restrictions on the cell stream arising from the segmentation of the packet traffic. First, it enforces a minimum spacing between the ATM cells proportional to the inverse of the PCR, and second, it ensures that the number of cells departing the shaper in any time unit “t”, denoted as D(t), always obeys the following relation:
D ( t )≦ SCR t+MBS, ∀t> 0,
[0024] where MBS denotes the maximum burst-size beyond the SCR. FIG. 3( b ) illustrates the ATM traffic output of the FR and IP interface card in accordance with the SCR/PCR shaping scheme with a minimum spacing 33 between ATM cells denoted as 1/PCR, and a minimum spacing 34 between groups of ATM cells in accordance with the relation (MBS−1)*(1/SCR−1/PCR). As mentioned above, this shaping may also be implemented by commercially available SAR (segmentation and reassembly) chips.
[0025] A second scheme, referred to as Stop/Go Shaping, shapes the packet traffic only when there is congestion at the egress ATM queue. As shown in the detailed illustration of the ATM switch in FIG. 4, congestion at the egress port 40 is detected based on a first “stop” threshold 36 a on the queue occupancy at the egress queue 35 which information is signaled back to the shaper buffer 27 located at the FR/IP Packet interface card 22 either via a hardwire connection, an built-in backpressure mechanism (not shown) or, preferably, a special virtual circuit, e.g., VC 37 setup within the switch. Shaping in this closed-loop scheme is simplistic in that the cell stream 30 derived from the Packet shaper buffer 27 is turned off, i.e., no ATM cells are allowed to leave the shaper, when congestion is detected at the egress queue 35 , and, is turned on again, i.e., ATM cells are allowed to leave the shaper, when the congestion subsides. As shown in FIG. 4, the abatement of congestion is detected based on a second “go” threshold 36 b on queue occupancy that is lower than the first threshold. Preferably, the first stop threshold 36 a is set near the memory limit of the egress queue 35 and the go queue occupancy threshold 36 b is set to provide a hysteresis in order to avoid queue oscillations about the single first threshold level. As in the first embodiment, SAR chips may be employed to shape, in accordance to the feedback, the ATM cell traffic in the second embodiment.
[0026] [0026]FIG. 5 illustrates the stop/go shaping scheme of the preferred embodiment whereby cells 30 d are transported to the egress buffer 35 at the switch port speed when the queue occupancy threshold is greater than the “go” threshold 36 b. As shown in FIG. 5, when the queue occupancy threshold is determined to be greater than the “stop” threshold 36 a, the traffic of ATM cells 30 e is stopped from being transported to the egress buffer.
[0027] It should be understood that instead of completely stopping transmission of the ATM traffic upon detection of congestion, transmission rate of segmented ATM cells 30 may be drastically reduced to a point where congestion at the egress buffer is avoided. Alternatively, in accordance with the principles of the invention, the stop/go ATM cell traffic shaping scheme of the preferred embodiment may be implemented by establishing multiple egress queue occupancy thresholds, e.g., three or more thresholds, to enable finer control of the performance. For instance, as shown in FIG. 6, egress queue 35 may have a first stop threshold 36 x enabling the ATM cell stream 30 to be transported from the shaper buffer 27 at a first reduced rate PCR 1 , for example, and, an additional stop threshold 36 z enabling the ATM cell stream 30 to be transported from the shaper buffer 27 at a second reduced rate PCR 2 , whereby PCR 1 >PCR 2 . Of course, the PCR 2 may be set to zero, to completely stop traffic flow when egress queue congestion is detected. It should be understood that, in this case, associated with stop threshold 36 x is go threshold 36 w, and associated with stop threshold 36 z is go threshold 36 y.
[0028] When egress queue length drops below go threshold 36 y after it has exceeded stop threshold 36 z, the output rate will switch from PCR 2 to PCR 1 . Later, if the egress queue length continues to drop below go threshold 36 w, then the output rate is switched back to PCR. Note that a three threshold scheme can be defined to achieve the same purpose.
[0029] For a given shaping scheme, performance metrics such as Frame Relay (FR) Packet loss rate and average delay (for packet traffic) and ATM cell loss, were evaluated using the queueing model, such as illustrated in FIG. 4, and choosing suitable simulation values for traffic parameters. It should be understood that a FR packet is considered lost when any of the cells constituting the packet is lost. As shown in FIG. 4, native ATM cell traffic 25 and ATM cells 30 generated from the Packet traffic compete for bandwidth and buffer space at the egress port queue 35 shown in the Figure as an ATM multiplexer 41 having a completely shared buffer of size B cells and implementing, for example, a first-come,first-served (FCFS) service discipline 39 . The cell transmission time at the multiplexer 41 is taken to be the unit of time. Both the packet source 30 and the native ATM source 25 are assumed to alternate between transmission (ON) and silent (OFF) periods according to, e.g., a 2-state Markov chain. When a source is ON, it is assumed to generate deterministically-spaced packets (cells) at time units of T on such as shown in FIG. 5. The number of packets (cells) in the ON period is taken to be geometrically distributed with mean P on . The length of the packet (cell) is taken to be a fixed L. The peak rate of the source is then given as p=L/T on and the mean rate m=p/b, where b denotes the burstiness of the source.
[0030] A simulation of the stop/go shaping method was conducted with the following traffic parameters: Frame relay packets size was fixed at L=1528 bytes with a T on , set to 16, P on set to 100, and b set to 6.667; ATM cell size was 53 bytes, P on set to 100, and b set to 6.667 values. The value of the T on , for ATM cell traffic was varied to keep the total load fixed at 80% of available bandwidth. In evaluating the performance of the stop/go shaping method, the FR frame traffic amounted to about 30% of the total traffic with the remaining traffic being native ATM cell traffic. For the simulation, it was assumed that the FR and ATM sources compete for a buffer space B equal to, e.g., 3200 cells at the ATM multiplexer. For purposes of the delay computations, a T 1 link is assumed, with the time for an ATM cell to be transmitted onto the link to be about 0.27 milliseconds and taken as unit time. Note, that in the stop/go simulation, there is a delay involved in signaling the congestion at the egress queue 35 to the interface card 22 which is taken to be equal to unit time.
[0031] In order to study the impacts of the stop/go thresholds on the FR and ATM cell losses for the Stop/Go Shaping method, the peak rate is fixed (same as no shaping rate) and the FR traffic is transmitted into the ATM multiplexer 41 with the Stop and Go thresholds varied. FIG. 7( a ) illustrates the FR and ATM cell loss rate (y-axis) versus the queue occupancy stop threshold (x-axis) and, FIG. 7( b ) illustrates a plot of the average FR frame delay versus the queue occupancy stop threshold (x-axis), for the Stop/Go Shaping method. As indicated by lines 5 , it can be seen that the FR loss is relatively unaffected by the choice of the stop threshold at the egress queue 35 because the loss can be completely controlled as long as the room between the Stop threshold and the egress buffer limit is sufficient to accommodate any ATM cells 30 in transit from the FR interface card 22 to the egress ATM card 40 before the congestion indication reaches the interface card 22 . For the considered parameter settings, this value is 16 cells which is generally small since the switching delay within a switch is typically small, e.g., in the order of microseconds, and hence the number of cells in transit is small. Hence, no loss occurs till the Stop threshold exceeds, e.g., 3184 for a buffer of size 3200, indicated in FIG. 7( a ).
[0032] As for the ATM cell loss both the Stop and Go thresholds have an impact. As shown in FIG. 7( a ), as both the Stop and Go thresholds increase, as indicated by lines 52 a, and 52 b, the ATM cell loss increases. Hence, smaller values of these thresholds are desirable. However, from a FR delay standpoint, higher values of the thresholds are desired as indicated by FR frame delay lines 53 a and 53 b plotted in FIG. 7( a ). As seen in the FIG. 7( b ) the relative impact of the thresholds on the delay is small however, and hence a value of the Stop threshold that is close to the value necessary to prevent frame loss, e.g., 3184, and the Go threshold to be small, e.g., 2560 may be chosen.
[0033] [0033]FIG. 8( a ) illustrates a plot of the FR Packet loss (y-axis) for different percentages of FR traffic (x-axis) for each of the different shaping methods and the no-shaping case, and FIG. 8( b ) illustrates a plot of the average FR frame delay in seconds (y-axis) for different percentages of FR traffic (x-axis) for each of the different shaping methods and the no-shaping case. FIG. 9 illustrates a plot of the ATM cell loss rate (y-axis) for different percentages of FR traffic (x-axis) for each of the different shaping methods and the no-shaping case. It can be seen that all of the shaping schemes dramatically reduce the FR loss with the PCR/SCR and the Peak Rate shaping schemes reducing the packet loss from about 15-45% for the no-shaping case to about 5-25% and the packet loss for the Stop/Go scheme being zero. This reduced FR loss is clearly achieved at the expense of some additional delays in all the schemes. For instance, with an equal mix of FR and ATM traffic, the delay is roughly doubled over the no-shaping case to about 1 sec. from 0.5 sec. Finally, the ATM cell loss for the PCR scheme is comparable to no-shaping case in general, but considerably improved in some cases. It is, however, almost uniformly worse for the PCR/SCR scheme, compared to the no-shaping case, probably due to a non-optimal choice of parameters, for this scheme. As shown in FIG. 9, the Stop/Go scheme results in reducing the ATM cell loss from about 0-8% as indicated by line 56 a (no-shaping scheme) to the range of 0-4% as indicated by line 56 b.
[0034] As shown in FIG. 9, the Stop/Go shaping scheme is extremely effective in limiting the FR and ATM cell loss at the expense of some additional delays for FR traffic. Further, the choice of “optimal” parameters for this scheme is extremely simple and result in predictable and uniformly superior performance.
[0035] The foregoing merely illustrates the principles of the present invention. Those skilled in the art will be able to devise various modifications, which although not explicitly described or shown herein, embody the principles of the invention and are thus within its spirit and scope. | An ATM switch for directing traffic flow of native ATM cell traffic and frame based packets between an input and an output port of the switch comprises a device for receiving native ATM cells and transporting the native ATM cells to the output port for output at a switch output rate; a device for receiving the frame based packets; a device for segmenting each received frame based packet into a corresponding plurality of ATM cells and transmitting the plurality of ATM cells to the output port at an ATM cell transmission rate; and a control device for controlling the ATM cell transmission rate to enable reduction of ATM cell loss at the output port and corresponding frame relay packet loss at the expense of packet delay. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to an improved clipper mechanism and more particularly to a clipper mechanism of the type wherein a main drive cylinder is utilized to simultaneously close the channel gate and drive the clip punch.
In the past, various patents have disclosed structure which provides a punch mechanism for driving a clip subsequent to gathering of material to be clipped and formation of a clip channel by a gate member. Such clipper mechanisms gather material to be clipped and hold the material in proximity to a clip die positioned in the path of travel of a clip driven by a punch. The material gathering and displacement mechanism is generally a gate operated by an air cylinder. As the gate gathers the material, it simultaneously completes formation of a channel for the clip.
A separate air cylinder generally operates the punch which drives the clip about the gathered material. Typical prior art patents disclosing such structure include Tipper, U.S. Pat. No. 3,394,528, U.S. Pat. No. 3,543,378 and U.S. Pat. No. 2,880,419.
As state above, the known prior art patents disclose formation of the channel for guiding the clip by closure of a gate which is effected by a mechanical or manually operated gate control mechanism separate from the drive mechanism for the clip punch. Such prior art apparatus does not generally disclose a mechanical linkage connecting a channel forming gate and a clip punch with the same drive cylinder. The present invention, however, provides such an apparatus.
SUMMARY OF THE INVENTION
In a principal aspect then, the present invention comprises an improved clipper apparatus of the type actuated by a fluid cylinder wherein a channel is formed for receipt of the clip by various channel forming members including a gate. A clip driving punch is driven by the fluid cylinder and, in turn, drives the clip through the channel about gathered material at the end of the channel. Additionally, a direct mechanical linkage is provided between the main drive cylinder and the channel forming gate. The linkage operates the gate in response to operation of the drive cylinder.
A control circuit for the apparatus and the optional cut-off knife is also disclosed. The unique knife includes a removable blade and provides more positive cutting action for gathered material relative to known prior art.
It is thus an object of the present invention to provide an improved clipper apparatus and, more particularly, a clipper apparatus of the type for attaching a clip about gathered material. The apparatus of the invention includes a gate and material gathering structure which also defines a punch and clip channel.
Another object of the present invention is to provide an improved clipper mechanism actuated by a single main drive cylinder.
Another object of the present invention is to provide an improved fluid control mechanism for operation of a clipper mechanism and, in particular, the main drive cylinder of a clipper mechanism.
Still another object of the present invention is to provide a clipper mechanism which provides sequential operation of a gathering and displacement gate mechanism and associated punch in response to actuation of a single main drive cylinder.
These and other objects, advantages and features of the present invention will be set forth in greater detail in the description which follows.
BRIEF DESCRIPTION OF THE DRAWING
In the detailed description which follows, reference will be made to the drawing comprised of the following figures:
FIG. 1 is a front perspective view of the improved clipper apparatus or clipper of the present invention in combination with a clip feed mechanism;
FIG. 2 is an enlarged perspective view of the mechanical linkage and gate mechanism as well as the trigger mechanism associated with the improved clipper apparatus of the present invention;
FIG. 3A is an enlarged partially schematic view of the lost motion linkage and punch drive linkage in the full upright or retracted position;
FIG. 3B is a view similar to FIG. 3A wherein the main drive cylinder has projected the punch partially toward to the fully extended position;
FIG. 3C is similar to FIGS. 3A and 3B and illustrates further extension of the main drive cylinder to the fully extended position;
FIG. 4 is a schematic view of the pneumatic control circuit for the clipper of the present invention;
FIG. 5 is an enlarged perspective view of the cutting knife associated with the clipper apparatus of the present invention;
FIG. 6 is a cross-sectional view of the cutting blade associated with the cutting knife taken along the line 6--6 in FIG. 5;
FIG. 7 is a view of the channel forming member of the clipper of the present invention; and
FIG. 8 is an enlarged cross-sectional view of the channel in the channel forming member taken along the line 8--8 in FIG. 7 and illustrating the opening for ingress of clips to the channel for engagement by the punch.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the improved clipper apparatus of the present invention includes a bracket assembly comprised of a lower support plate 10 with a guide 12 mounted thereon. A C-shaped die support 14 defined by a vertical plate is attached to the guide 12 and extends upwardly from plate 10. As illustrated in FIGS. 3 and 7, the die support 14 includes a grooved channel 16 for receipt of a punch 18 and clip 20. The punch 18 drives clip 20 downward in channel 16 against a die or anvil 30.
The die support 14 is C-shaped an thus defines a throat opening 22 for receipt of gathered material about which the clip 20 is to be placed. A gate 24 is pivotally attached by means of pin 26 through opening 28 to the die support 14. The gate 24 may thus be rotated to close the throat opening 22 and complete the grooved channel 16 as shown in FIG. 3C. Alternatively, the gate 24 may be rotated to its full open position as illustrated in FIGS. 2 and 3A for admission of material to the throat opening 22.
The die 30 is positioned in support 14 adjacent the lower end of channel 16 in the manner known to those skilled in the art. The die 30 thus cooperates with the legs of a clip 20 to form those legs about material maintained in the throat opening. The general method of clip 20 formation is also known to those skilled in the art.
First and second side gathering plates 32 and 34 are attached to the opposite sides of the gate 24. Plates 32, 34 assist in gathering and positioning material placed in the throat opening 22 prior to attachment of a clip 20 thereto. The apparatus thus far described is generally known to those skilled in the art.
Unitary Drive for Gate and Punch
A single main drive cylinder 36 is mounted on a bracket assembly 38 attached to the die support 14. The main cylinder 36 includes a projecting rod 40 extending from piston 122 in FIG. 4, thereby defining a stroke of the clipper. When the rod 40 is in the position illustrated in FIG. 3A, the clipper is in a retracted position. Extending the rod 40 to the position shown in FIG. 3C, places the clipper in a fully projected or extended position. Actuation of the drive cylinder 36 and thus extension of the rod 40 causes punch 18 to be driven through grooved channel 16 against a clip 20. Thereby, the clip 20 is formed against the die 30 and closes about material gathered in the throat opening 22 by the gate 24 and gathering plates 32 and 34.
Rod 40 is connected to a platen 42. Platen 42 is maintained in proper alignment by means of bushings 43 slidable on guide rods 44 fixed to the bracket assembly 38. Punch 18 is then attached to the opposite side of platen 42 and moves in response to movement of platen 42 with respect to fixed guide rods 44.
Platen 42 includes an outward extension 46 having a downwardly projecting post 48 attached thereto and movable therewith. Attached to the lower end of the post 48 is a cam actuator 50. The cam actuator 50 includes a cam track 52 having a horizontal first run 54 and a vertical second run 56. A follower or link pin 58 attached to one end of a link 60 is positioned in the track 52 and projects into a cam slot 62 in a cam plate 64 attached to the bracket assembly 38. The follower or link pin 58 thus simultaneously follows the path defined by both cam track 52 and cam slot 62.
The opposite end of link 60 is pivotally attached by pin 66 to the gate 24. Thus, the cam actuator 50, link 60 and gate 24 move in response to movement of platen 42. The movement imparted to the gate 24 is pivotal motion about pin 26. When the rod 40 is in its retracted or unextended position, the gate 24 is open as illustrated in FIG. 3A. When the rod 40 is in its extended position, the gate 24 is closed as illustrated in FIG. 3C. FIG. 3B illustrates an intermediate position of the platen 42 through the gate 24 has been almost fully rotated to a closed position.
Note that the relationship of track 52, slot 62 and follower 58 provides a lost motion action at the lower end of the stroke of rod 40. Thus, as the rod 40 is initially extended from the position of FIG. 3A, follower 58 is maintained in first run 54 due to the cooperation of upper portion 68 of slot 62 on follower 58. As the rod 40 is extended to the position illustrated by FIG. 3B, the follower 58 is caused to travel from the first run 54 to the second run 56 of track 52 by action of segment 70 of cam slot 62 on follower 58. Segment 72 of cam slot 62 maintains the follower 58 within the second run 56 of slot 52. Segment 70 is an intermediate inclined segment of slot 62 and thus provides a gradual transition from run 54 to run 56. Segment 70 is preferably inclined from the horizontal and may be constructed to define the lower end of slot 62 as discussed below.
When the follower 58 is in the second run 56, no further rotational motion is imparted by movement of platen 42 to the gate 24. In other words, any additional motion is accounted for by movement of follower 58 within second run 56. Note that slot 62 may include a lower segment 72 which accommodates the lost motion action. Alternatively, the inclined segment 70 is designed to define the lower termination point of follower 58 in slot 62. Follower 58 will then bottom at the end of segment 70 and remain in fixed position pending reversal of stroke of piston 122.
In this manner, the rod 40 may be extended to its full projected position, thereby fully actuating punch 18 subsequent to complete closing of gate 24. In other words, the gate 24 is initially and sequentially rotated into proper closed position (as shown in FIG. 3B) prior to driving a clip 20 tightly about gathered material in the throat opening 22. Initial closing of gate 24 is necessary to form channel 16 for clip 20.
As discussed, a single main drive cylinder 36 is utilized to operate both the punch 18 and gate 24. Both punch 18 and gate 24 are positively driven and positively withdrawn by operation of cylinder 36. That is, upon reversing the stroke of the main cylinder 36, the punch 18 is initially withdrawn. Subsequently, the gate 24 is positively rotated in the opposite direction to assume the position illustrated by FIG. 3A.
Trigger Adjustment
Referring now to FIG. 2, some additional important features of the improved clipper of the present invention are illustrated. As shown in that figure, a trigger 73 is attached to a rocker shaft 74 pivotally mounted on a trigger bracket 76. A lever arm extension 78 attached to the opposite end of shaft 74 is positioned to engage a limit switch arm 80 associated with an air limit switch or valve 82. Valve 82 includes an air inlet line 84 and an air outlet valve 86, the function of which will also be described in further detail with reference to FIG. 4 below.
Rotation of the lever arm extension 78 will actuate valve 82. Lever arm extension 78 is rotated in response to movement of trigger 73 in the counterclockwise direction in FIG. 2. This occurs whenever material to be clipped is placed within the throat opening 122 by an operator. For example, a plastic bag which is to be clipped would be pushed into the throat opening and, upon doing this, would also engage the trigger 73, thereby actuating the valve 82.
The trigger bracket 76 is mounted on a lead screw 84. The opposite end of the bracket 76 includes a slot 86 which is engaged with a flange 88 on a fixed bracket 90. A trigger adjustment knob 92 in FIG. 1 is mounted on the bracket assembly 38 and operates bevel gears 94 to thereby rotate lead screw 84. The lead screw upon rotation will move the trigger bracket 76 forward or backward depending upon the sense of rotation. In this manner, the trigger 73 is placed forward or back in the throat opening 22 and the triggering mechanism for the pneumatic circuitry described below can be adjusted.
Knive Cut-Off Construction
FIGS. 2, 5 and 6 illustrate the knife cut-off mechanism associated with the improved clipper of the present invention. A knife support member 96 is pivotally attached to the die support 14. A knife blade 98 is removably inserted in a slot 100 provided. The blade 98 includes a spring member 102 which fits in an opening 104 of member 96 to retain the blade 98. Consequently, the blade 98 is removable upon flexure of the spring portion 102 from locking engagement with opening 104.
The opposite end of knife support member 96 is attached to a rod 106 extending from a knife operating cylinder 108. To operate the knife blade 98, the rod 106 is retracted thereby rotating the knife support 96 in the counterclockwise direction as illustrated in FIGS. 2 and 5. This causes the knife blade 98 to pass adjacent the throat opening 22 and the die 30, thereby cutting off any material projecting beyond the die 30.
Method of Operation and Control Circuit
Referring now to FIG. 4, the method of operation of the improved clipper of the present invention will be described. As previously recited, valve 82 controls the initiation of operation of the clipping mechanism. Valve 82 is a control valve and provides an output through line 86 to a main pilot valve 110. When valve 82 is in the closed position, illustrated in FIG. 4, pressurized air passes through input 112 of main pilot valve 110 and through outlet 114. Pressurized fluid through the line 114 or the first main outlet of the pilot valve 110 is directed in parallel fashion to inlet 116 of main drive cylinder 36 and to inlet 118 of the diaphragm pilot valve 120.
Pressure through inlet 116 acts against the lower side of piston 112 of main drive cylinder 36, thereby maintaining rod 40 in a retracted position as illustrated. Pressure through inlet 118 of diaphragm valve 120 acts on diaphragm 124 and valve member 126 so that pressurized fluid to the inlet 128 of valve 120 is not directed to any outlet. The outlet 114 is also connected to the inlet 128 of knife cylinder 108. Pressure acts on piston 107 and maintains the rod 106 of knife cylinder 108 in a projected position as illustrated in FIGS. 4 and 5.
Upon actuation of arm 80 to open valve 82, pressurized fluid passes through line 86 and shifts valve member 130 of valve 110 to the right. Upon transfer of the valve member 130, pressurized air through inlet 112 then passes to the second outlet 132. First outlet 114 is now exhausted through exhaust outlet 134. Thus, the lower side of piston 122 is exhausted. Similarly, the top side of piston 107 associated with rod 106 is exhausted. Pressure is also released from the top side of diaphragm 124 associated with valve 120.
When the fluid pressure is provided through the second outlet 132, the piston 122 and associated rod 40 are immediately driven toward the extended position. The operation of the punch 18 and gate 24 in response to movement of rod 40 is effected as previously described.
After some time delay, the valve member 126 shifts upward from the position illustrated in FIG. 4 so that air pressure through inlet 128 may pass through outlet 136. This time delay is provided as a result of orifice 138 which permits air to leak into chamber 137 on the bottom side of diaphragm 124 at a slow rate thereby preventing immediate snap action of valve member 126. Preferably, the size of the orifice 138 is adjustable in order to set the time delay of valve member 126. This time delay is necessary in order to delay operation of the knife cylinder 108 until a clip 20 has been successfully attached to gathered material.
Subsequent passage of pressurized air from outlet 136 to inlet 140 of knife control valve 142 causes valve member 144 to be shifted permitting pressurized air from inlet 146 to pass through outlet 148. Pressurized air through the outlet 148 acts on lower side of piston 107, thereby retracting rod 106 and operating the knife blade 98.
The outlet 148 is also connected with pilot inlet 150 of valve 110 causing the pilot valve member 130 to be shifted back toward the original position illustrated in FIG. 4. Shifting of valve member 130 thereby automatically reverses the operation since second outlet 132 then is exhausted through exhaust port 135.
Note that additional lines as at line 152 may be provided to effect further operations. For example, line 152 may be directed to a clip feeding assembly 154 in FIG. 1 or a clip advance mechanism 156 in FIG. 1. Also, additional lines may be included in parallel with the first outlet 114. For example, line 155 may be connected through a conduit to a clip blow out passage 157 in FIGS. 3A and 5. Such a clip blow out passage 157 provides air directly to the face of the die 30 to clean off the die face prior to attachment of additional clips.
While in the foregoing there has been set forth a preferred embodiment of the present invention, it is to be understood that the invention shall be limited only by the scope of the following claims and their equivalents. | An improved clip attachment apparatus includes a main drive cylinder operative to drive a punch against a clip. A mechanical linkage also connects the drive cylinder with a gate. Operation of the main drive cylinder simultaneously closes the gate to form the punch channel and drives the punch. The mechanical linkage includes a lost motion feature to insure that the gate will be closed prior to attachment of the clip around material gathered at the lower end of the punch channel. An improved knife for cutting the clipped material and an improved pneumatic circuit for sequentially controlling the drive cylinder and the knife cylinder are disclosed. Finally, an adjustable trigger mechanism for initiating operation of the clipper is disclosed. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Section 371 of International Application No. PCT/EP2011/003317, filed Jul. 5, 2011, which was published in the German language on Jan. 19, 2012, under International Publication No. WO 2012/007115 A1 and the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a device for controlling the temperature, in particular for cooling, of an LED lamp or LED modules of an LED lamp, wherein the device comprises a supply line for feeding a fluid and multiple heat exchangers connected to the supply line, wherein multiple LEDs are arranged on each heat exchanger and are coupled to the heat exchanger with respect to heat transfer, so that the fluid can control the temperature, in particular cool, the LED lamp or the LED modules. The invention also relates to a method for controlling the temperature, in particular cooling, of an LED lamp or at least two LED modules of an LED lamp, using such a device and to a method for curing of a light-cured pipe using such a device.
[0003] For light-cured pipe rehabilitation, mercury vapor discharge lamps have been used successfully for approximately 20 years. These usually require no cooling. For the curing of pipe liners having small pipe diameters in the range of household connections (DN 300-DN 50, typically DN 160) there are significant restrictions for the traditionally used UV lamp technology (gas discharge lamps) with respect to the achievable minimum dimensions (diameter and length) of the lamps. The requirement of a mechanically robust holder and protective device for the bulb lamps also involves disadvantages, because these protective elements cause shadows that are significant, in particular for small pipe diameters.
[0004] For curing a light-cured pipe liner in the field of pipe rehabilitation, in particular in the range of household connections for pipes having small diameters (less than or equal to DN 300), a compact, powerful lamp is required that is cylindrical, if possible.
[0005] Due to their small geometrical dimensions and usually high optical outputs in the range of 100 W and their potentially good energy efficiency, light emitting diodes (LEDs) are suitable radiation sources for realizing small, powerful special lamps for UV curing applications, in particular in the field of trenchless pipe rehabilitation. They allow the realization of compact, efficient light sources, which can be adapted to the optical and geometrical requirements of the materials to be cured. In addition, LEDs require no wait time for achieving their full operating power, because they can be switched quickly (in the range of milliseconds or even shorter). LEDs also emit in narrow spectral ranges with half value widths of typically 10-40 nm, so that no infrared radiation is emitted by UV-LEDs and blue LEDs. Therefore, thermal dissociation of the polymers to be cross-linked can be avoided.
[0006] The combination of the usually minimal available space for the lamp of a curing device for pipe rehabilitation and the required high power densities represents a great challenge for the structure and the function of a cooling body of such an LED lamp. This applies especially when several of these LED lamps must be operated one after the other in a pipe and good movement along curves in pipes having bends is desired.
[0007] The basic use of LEDs for pipe rehabilitation is described in International patent application Publication No. WO 2005/103121 A1. The use of LEDs for the UV curing of pipe liners is also described in European patent application publication EP 1 959 183 A1, Japanese patent application publication (Kokai) JP 2008-175381 A and International patent application Publication No. WO 2008/101499 A1. LED curing systems for pipe rehabilitation are described there.
[0008] These LED lamps, which have high power densities and are used as curing devices for pipe rehabilitation, often require very efficient cooling that prevents a degraded function due to overheating of their components. Such narrow LED lamps, which have linear constructions and are used, for example, in pipes or other environments that are tightly limited in terms of space, always have the problem that there is little space for additional parts used for cooling the LED lamps or LED modules of the LED lamps. The same problem also occurs in narrow curing devices, which have linear constructions and in which the parts must be heated in the narrow space to an operating temperature in order to guarantee a reliable functioning of the parts, for example LED lasers.
[0009] For a material to be cured by light-initiated polymerization, intensities from a few mW/cm 2 up to a few 10 W/cm 2 are typically required, which explains the previously mentioned required optical outputs of the LED lamps. Because the efficiency and the service life of LEDs (ratio of optical output power and the electrical operating power) are inversely proportional to the operating temperature of the LEDs, good cooling of the LEDs is required.
[0010] To be able to control the temperature of, that is cool or heat, the parts, heat must be fed to these parts or heat must be conducted away from these parts through the narrow, hose-shaped construction. As the medium for transporting the heat energy, fluids, for example air or water, are preferred.
[0011] An operation of the heat exchangers or cooling bodies in series can be technically useful, because the supply and return of a cylindrical heat exchanger/cooling body can be easily attached to opposite ends. The fluid/medium flows through the supply into the cooling body, flows through this cooling body in the axial direction, and leaves the cooling body on the opposite end through a return connection. The supply of the next cooling body in the series is then connected to the return of the preceding cooling body and the series connection is realized in this way.
[0012] This connection, however, causes a disadvantageous, sequentially increasing advance temperature of the heat exchangers/cooling bodies that carry a flow of the cooling medium downstream and thus a lower efficiency and service life of these modules, in particular the final module that has the highest operating temperature. Increasing the flow rate of the coolant is one possibility for reducing this effect. However, this is also associated with an increased pressure drop whose compensation requires either an increase in the operating pressure, which places a higher load on the heat exchanger/cooling body, or an increase in the line cross section, which is often not possible due to the tight space relationships and the higher resulting weight of the system.
[0013] From the publication WO 2008/101499 A1, a device according to the class for controlling the temperature of an LED lamp having a linear construction or LED modules of an LED lamp is known. In the interior, the device comprises a supply line in the form of a pipe, which carries a flow of air, in order to cool LEDs arranged on the lateral surface of the pipe with the air flow. In the supply line there are openings through which the air flow can escape outwards into a pipe to be rehabilitated. A return line for returning the heated air flow is not provided.
[0014] Here, it is a disadvantage that a liquid fluid, such as water, cannot be used, because water, if it came into contact with the LEDs on the outside, could destroy these parts. Liquid fluids, however, can absorb heat significantly more efficiently than gaseous fluids. The fluid also heats up as it passes each device module, so that the temperature of the front LED modules is more strongly controlled or cooled than the rear LED modules. This cooling system involves a serial connection of the heat exchangers arranged one after the other (serial flow of fluid cooling media). This leads, for example, to service lives of different lengths for the LEDs in the different LED modules.
BRIEF SUMMARY OF THE INVENTION
[0015] The object of the invention is to solve these problems. In particular, a uniform control of the temperature of the LED lamp or the LED modules of an LED lamp should be achieved. It should also be possible to use liquid fluids for the temperature control, without possibly damaging the LEDs.
[0016] This object is achieved in that the device comprises a return line for returning the fluid, wherein
[0017] the supply line and the return line are each connected to each other in a fluid-tight manner by an L-piece at one of their ends and also by at least one T-piece in the supply line and at least one T-piece in the return line, or
[0018] the supply line and the return line are connected to each other in a fluid-tight manner by an L-piece at the end of the supply line that is connected to a T-piece in the return line, and an L-piece at the end of the return line that is connected to a T-piece in the supply line, or
[0019] the supply line and the return line are connected to each other in a fluid-tight manner by an L-piece at the end of the supply line that is connected to a T-piece in the return line and an L-piece at the end of the return line that is connected to a T-piece in the supply line, and also by at least one T-piece in the supply line and at least one T-piece in the return line,
[0020] so that the fluid flows spatially separated from the LEDs and so that the supply line and the return line have at least two fluid connections connected in parallel to each other, wherein the heat exchangers are arranged in the fluid connections or the heat exchangers are the fluid connections.
[0021] Here, it can be provided that the heat exchangers connected in parallel can be shiftable, compressible, and/or movable relative to each other.
[0022] It can be further provided that the device has a modular construction and comprises LED modules, wherein one LED module comprises two L-pieces and at least one LED module comprises two T-pieces, or
[0023] two LED modules comprise an L-piece and one T-piece and/or at least one additional LED module comprises two T-pieces,
[0024] and wherein the LED modules also comprise a fluid connection with a heat exchanger, wherein the LED modules are connected to each other, in particular in a detachable manner, by supply line parts and return line parts, so that additional LED modules can be easily replaced, removed, and also installed.
[0025] Here, it can be provided that the supply line parts and return line parts, which connect the LED modules to each other are flexible, expandable, and/or compressible, in particular are flexible plastic hoses and/or corrugated boots, preferably with springs, so that the device can be pulled along an arc-shaped path in a pipe.
[0026] One improvement of the device provides that the LED modules are arranged in series one after the other geometrically in a line.
[0027] It can also be provided that the return line is arranged parallel to the supply line.
[0028] It can be further provided that the fluid in the return line flows in the opposite direction of that in the supply line.
[0029] It can also be provided that the device comprises the LED lamp or the LED modules.
[0030] Here, it can be further provided that the LED modules have the same construction, in particular they are identical.
[0031] One improvement of the device provides that the LED lamp or the LED module is a curing device, in particular a light source for pipe rehabilitation, wherein the fluid does not come in contact with the material to be cured.
[0032] It can also be provided that each LED module comprises at least one substrate having at least one LED, preferably at least one high-power LED, which are arranged preferably in a ring-like shape, such that the LEDs emit radiation outwardly, preferably in all directions of a plane perpendicular to the linear structure of the LED lamp or the LED modules.
[0033] Here, it can be provided that multiple LEDs are mounted as chip-on-board (COB) on a substrate.
[0034] The use of chip-on-board (COB) technology allows the realization of high intensity light sources having homogeneous emission patterns and having cylindrical geometry and having high optical outputs in the range of a few watts to several 100 watts. Through the possibility to use LEDs having higher powers, a quicker curing of the pipes to be cured, and thus an acceleration of the curing process, is achieved.
[0035] One improvement of the invention provides that each LED module comprises one connection unit on which supply lines are connected, which comprise the supply line, the return line, and electrical cables that are at least partially connected to the LEDs.
[0036] Another construction according to the invention provides that each LED module is enclosed by a housing, in particular a glass, stainless steel, or plastic housing.
[0037] Another alternative construction of the invention provides that the device comprises a supply unit, which comprises a fluid regulator for controlling the flow rate and/or the temperature of the fluid through the supply line and/or the return line.
[0038] Here, it can be provided that the supply unit comprises an LED controller for controlling the voltage applied to the LEDs.
[0039] In addition, it can be provided that the device and/or the LED modules comprise at least one sensor, preferably a temperature sensor, an illumination strength sensor, a current sensor, and/or a voltage sensor.
[0040] Here, it can be advantageous if the sensor or sensors are connected to the fluid regulator and/or to the LED controller in the supply unit.
[0041] It can also be provided here that the electrical cables contact the supply line to at least one sensor and/or a drive device and connect with the supply unit.
[0042] Another construction of the invention provides that each heat exchanger and/or each LED module has a cylindrical or ring-shaped structure having a circular or polygonal cross section.
[0043] Here, it can be provided that at least two adjacent openings are provided for the supply and the return of the fluid on the inside and/or the side surfaces of the heat exchanger, which are separated from each other by a partition wall in the heat exchangers, such that the fluid flows through the heat exchanger essentially within its entire extent.
[0044] Further, it can be provided here that the supply line and the return line extend through the opening of the cylindrical or ring-shaped LED modules and/or the cylindrical or ring-shaped heat exchangers.
[0045] In general, it is advantageous for the devices according to the invention if the supply line parts and return line parts, which connect the modules to each other, are flexible, in particular flexible plastic hoses, so that the device can be pulled along an arc-shaped path in a pipe.
[0046] It can also be provided that, at the contact surfaces to the LEDs or to the substrate, the heat exchangers are made at least in some areas from a material with good heat conducting properties, in particular from a metal, preferably copper, aluminum, brass, or steel, and/or from a ceramic, preferably Al 2 O 3 or AlN.
[0047] One improvement of the invention provides that the fluid is a gas, in particular compressed air or nitrogen, or a liquid, in particular water.
[0048] It can also be provided that each LED module is designed for an optical power between 1 watt and 1000 watts.
[0049] It can be further provided that the LED lamp at least partially, in particular the LED modules, can be cooled and/or heated by the fluid.
[0050] It can also be provided that the supply line, the return line, the T-pieces, the L-pieces, and the heat exchangers are connected to each other in a fluid-tight manner.
[0051] One advantageous improvement provides that shutters are arranged or can be mounted in or on the fluid connections.
[0052] It can also be provided that the cross section is adjusted to the fluid connections or shutters are arranged in or on the fluid connections, such that all of the heat exchangers are flowed through with a similar volume flow of the fluid, so that the volume flows through the heat exchangers differ by a maximum factor of 3, preferably by a maximum factor of 2.
[0053] The object is also achieved by a method for controlling the temperature, in particular cooling, of an LED lamp or at least two LED modules of an LED lamp using such a device, wherein a fluid is fed through the supply line to the at least two heat exchangers, a heat transfer takes place there with the LED lamp or the LED modules, and the fluid is then returned through the return line.
[0054] Here, it can be provided that the fluid flows out of the return line into a supply unit, is cooled or heated there, and is then fed back into the supply line, in order to regulate the temperature of the fluid in the supply line, in particular as a function of the signals of at least one sensor, and/or the flow rate of the fluid is regulated, in particular as a function of the signals of at least one sensor.
[0055] In particular, the object is achieved for a method for curing a light-cured pipe, in that such a device for cooling a curing device, in particular a light source for pipe rehabilitation, is inserted into the pipe together with the curing device, and then the pipe is cured by the light from the LEDs, while the device and the curing device are moved through the pipe, and the curing device or the LED modules of the curing device are cooled by the device, in particular using a method as already described.
[0056] Finally, it can be provided that the flow rate of the fluid, the temperature of the fluid, the radiant power of the LEDs, and/or the velocity of the device in the pipe is controlled, in particular as a function of the measured values of a sensor, in particular a temperature sensor, an illumination strength sensor, a current sensor, and/or a voltage sensor.
[0057] The invention is thus based on the surprising finding that even heat exchangers arranged geometrically in series can be connected in parallel in terms of the temperature-controlling fluid, and therefore an equally strong temperature-controlling effect can be achieved at the different heat exchangers. All of the device modules, which are connected to the heat exchangers, are cooled or heated to an equally strong degree by this device. In this way, homogeneous temperature conditions are achieved in the regions of the device to be controlled.
[0058] In contrast to the known series connection of cooling bodies/heat exchangers for LED lamps for pipe rehabilitation, the present invention solves the resulting problems by arranging the cylindrical cooling bodies/heat exchangers geometrically in series, but connecting these parts in parallel in the cooling circuit, wherein each of the individual cooling bodies carries a flow in the peripheral direction of the extent. This is achieved in that the supply line and the return line of the cooling body/heat exchanger are arranged in the interior of the cylinder, and these are each connected by a T-piece or an L-piece to a common supply line or common return line for all of the cooling bodies/heat exchangers. These T-pieces and L-pieces can be realized either as individual components, whose branch connections are each connected to the supply line or the return line of the cooling body/heat exchanger. Likewise, its temperature distribution function can be integrated directly in the cooling body/heat exchanger, so that the cooling body/heat exchanger has two feed connections and two return connections on each end.
[0059] The parallel connection (coupling) of the heat exchangers allows the same supply temperature to the individual heat exchangers, even though these are arranged geometrically in series (for example one after the other in a pipe). In a fitted system (line resistance, flow resistance of the heat exchangers and connection ports are customized), an equal volume flow can be set through all of the heat exchangers, and thus the same temperature conditions can be realized for all of the LED modules (for example the same cooling conditions for all of the LED modules).
[0060] Then, the heat exchanger of the LED lamp farthest away from a rear cooler also has the same temperature as the closest, which is different from heat exchangers in a series connection. Through the parallel connection, the same operating and output parameters that are dependent on temperature: efficiency, service life, emission wavelength, and rated electrical input, can be realized for all of the coupled LED modules.
[0061] In addition, a parallel connection causes a lower pressure drop in the overall system than a series connection. This is relevant, in particular, if the flow resistances in the lines are small compared with those of the heat exchangers.
[0062] Another advantage is achieved in that the length of the individual LED modules can be reduced, which improves the ability of the device to move along curved paths.
[0063] As a light source for pipe rehabilitation in the field of household connections, according to the invention an LED lamp has been found that allows a homogeneous irradiation of the inner wall of a pipe having small, round cross sections of approximately 15 cm and higher radiant powers of several 100 mW/cm 2 up to a few W/cm 2 . In addition, the LED lamp can be moved along curved paths and pulled in 45° and 90° bends.
[0064] The necessary power density for the homogeneous illumination of the inner wall of pipes under consideration of the small diameter and the required ability to move along curved paths is achieved by over three-hundred LEDs on a cooling body acting as a heat exchanger having a diameter of approximately half the pipe diameter (approximately 8 cm) and a length of approximately one fourth of the diameter (approximately 3.5 cm).
[0065] To achieve the required radiation dose for pulling speeds of a few centimeters to a few tens of centimeters per minute (greater than 30 cm/min), the modules should be coupled to each other as flexibly as possible.
[0066] The high optical outputs in the range of a few watts to several 100 watts associated with this arrangement require compact and efficient cooling bodies, due to the necessary compact arrangement of the LED lamps and the typical efficiency of LEDs (typically in the range from 1% to 50%, normally 10% to 30%).
[0067] Because LEDs are assembled on flat substrates, the substrates are arranged on an elongated, possibly cylindrical body having polygonal cross section, preferably a triangular, quadrangular, pentagonal, hexagonal, or octagonal cross section.
[0068] Because at most several LED modules are required for achieving the target dose, the LED modules can be coupled flexibly one behind the other.
[0069] For maintaining the efficiency and for improved operation with additional temperature-dependent parameters, a cooling system was developed, which allows the parallel operation of LED modules located one behind the other. Here, the supply and return of each heat exchanger is connected by a T-branch or an L-branch to a common supply line or common return line for all of the heat exchangers, which lines are guided centrally through the heat exchangers.
[0070] Therefore, in a customized system, each heat exchanger can be operated at the same supply temperature with a comparable cooling power or heating power, and thus an equal efficiency and service life are maintained throughout the LED modules located spatially one after the other.
[0071] The individual heat exchangers carry a flow preferably in the peripheral direction. The fluid, which can be a gas, for example compressed air or nitrogen, for low power requirements, but is otherwise a liquid, and for higher powers a medium having high heat capacity, for example water, here flows close to the outer surface along the periphery of the heat exchanger, so that the substrates having the LEDs are cooled effectively.
[0072] By the parallel connection of the heat exchangers arranged spatially one after the other, the flow resistance of the fluid/cooling medium is also kept low in the system, so that, for the same volume flow of the fluid, supply lines having smaller diameters can be used than in a series temperature-control system.
[0073] A series cooling system can indeed have a similar overall cooling power, but then there is a higher temperature difference of the heat exchangers relative to each other. This is the case, in particular, when the flow resistances of the heat exchanger are comparable or larger than those of the lines that connect the heat exchangers to each other. In the reverse case, an adaption of the flow resistances to the individual heat exchangers for regulating a uniform volume flow can be necessary, which can be realized, for example, by the use of shutters.
[0074] The integration of the connection function in the center of the heat exchangers also allows the heat exchangers to have a short length, which improves the ability of the system to move along a curved path.
[0075] A device according to embodiments of the invention thus has a whole series of advantages.
[0076] A parallel connection for the supply of a cooling or heating medium to heat exchangers located one after the other allows, in a customized system, the operation of all of the heat exchangers under the same conditions, in particular at the same supply temperature and same volume flow of the fluid through the individual heat exchangers. For the latter, in the case of small supply lines and low flow resistances, measures could be required on the heat exchanger for adapting the volume flow rates, for example the mentioned regulating shutters. This case, however, represents a limiting case that usually can be avoided. In contrast to a space-saving serial supply, the more complicated parallel supply avoids a sequential rise or drop in the supply temperature in the direction of the heat exchanger spatially farthest away from the supply to the system. This property is relevant, in particular, for the cooling of LEDs that have strongly temperature-dependent properties and whose efficiency, emission wavelength, service life, and operating voltage can be adversely affected.
[0077] For the same line cross section, comparable connection technology, and identical heat exchangers, the flow resistance of the parallel system is lower than that of the series system. Accordingly, either for the same operating pressure, connection lines having smaller nominal widths can be used for realizing the same volume flow, or for the same nominal widths, the connection lines can achieve higher volume flows and thus better cooling or heating powers for the same operating pressure. For adjusting the volume flows in the limiting case of high line resistances and low flow resistances in the heat exchangers, the use of different shutters for adjustments is then also possible.
[0078] The heat exchangers can be constructed so that the fluid flows past in a circular flow and almost covering the entire surface, close to the outer surface, so that efficient temperature control is achieved.
[0079] The line in the heat exchanger can be macroscopic or microscopic (for example micro-channel cooling).
[0080] The possibility for increasing the efficiency of the cooling power can be used for increasing the efficiency of the LED lamp and/or for increasing the optical output limit of the system, because the LED parameters are dependent on the temperature.
[0081] By the paired switching of supply and return connections to the heat exchangers of every second LED module, the circulating direction of the fluid can be set in opposite directions from module to module. Possible gradients that can appear in the heating of the cooling medium or in the cooling of the heating medium between the supply and return and can cause, for example, a gradient in the optical output of LEDs along the periphery of a cylindrical LED module, can be distributed in an alternating pattern, so that possible effects of these gradients are lessened or even prevented during pulling processes.
[0082] The arrangement of the connection elements in the interior of the cylindrical heat exchangers makes possible a short length of the LED module and thus a better ability to move along curved paths than if the connection elements were positioned on the ends of the heat exchangers.
[0083] Positioning the connection elements in the interior of the heat exchangers protects them from mechanical effects that could cause leaks. The connection mechanism of the connections can vary: T- or L-pieces connected by hoses and hose clamps, couplings that can be screwed on with integrated T- and L-shaped features or coupling elements that can be plugged in.
[0084] The use of coupling elements that can be plugged in allows the construction of a modular LED system, in which every module is replaceable, in which the supply media (current and cooling medium) can be connected and disconnected by a locking or non-locking coupling mechanism (possibly can be disconnected without dripping). The connection can be disconnected and connected on both sides of the module, so that it is completely replaceable without having to disassemble the entire system in sequence (starting from one side).
[0085] Several LED modules can be coupled to each other by rigid or by elastic, expandable, and/or compressible connections. A possibly smaller line diameter of the supply lines for the temperature control can have positive effects on the weight of the system and also on the flexibility of the system (ability to move along curved paths).
[0086] Several systems coupled spatially one behind the other can also be used for the uniform heating or uniform cooling of cylindrical bodies. Wherever the present text refers to a cooling circuit, cooling output, cooling body, or cooling medium, according to the invention this could also be a heating circuit, heating output, heating body, or heating medium, respectively. With a heating circuit, pipes to be cured can also be cured thermally by contact heating or thermal radiation. Likewise, components, for example lasers, can also be heated to a certain temperature, in order to achieve a constant output and an exact wavelength in the temperature-controlled laser.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0087] The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
[0088] FIG. 1 is a schematic view of a device according to an embodiment of the invention for controlling the temperature of a device;
[0089] FIG. 2 is a schematic, perspective view of a heat exchanger of a module of a device according to an embodiment of the invention;
[0090] FIG. 3 is a schematic, perspective view of a device according to an embodiment of the invention comprising four heat exchangers according to FIG. 2 ;
[0091] FIG. 4 is a schematic cross-sectional view of a device according to an embodiment of the invention having a plurality of LEDs; and
[0092] FIG. 5 is a schematic representation of a device according to an embodiment of the invention having a device whose temperature is to be controlled.
DETAILED DESCRIPTION OF THE INVENTION
[0093] FIG. 1 shows a schematic view of a device according to an embodiment of the invention for controlling the temperature of an LED lamp or LED modules of an LED lamp and sketches a cooling or heating circuit. The device comprises a supply line ( 1 ) and a return line ( 2 ) that are both divided into different sub-areas. The supply line ( 1 ) and the return line ( 2 ) are formed by pipes. Between each of the sub-areas of the supply line ( 1 ) and the return line ( 2 ) there are three T-pieces ( 3 ). At the end of the supply line ( 1 ) and at the beginning of the return line ( 2 ) there is an L-piece ( 4 ). The T-pieces ( 3 ) and the L-pieces ( 4 ) are likewise formed by pipes. Between every two adjacent T-pieces ( 3 ) of the supply line ( 1 ) and the return line ( 2 ) and the two L-pieces ( 4 ) there are heat exchangers ( 5 ) that have tubular constructions.
[0094] All of the pipe pieces ( 1 , 2 , 3 , 4 , 5 ), that is the supply line parts ( 1 ), the return line parts ( 2 ), the T-pieces ( 3 ), the L-pieces ( 4 ), and the heat exchangers ( 5 ), can be connected to each other in a fluid-tight manner by various methods. The pipes can be either connected rigidly to each other, for example welded, connected to each other by press fittings, or the pipes can be connected to each other in a detachable way, for example one inserted into the other or attached to each other by coupling pieces or hose clamps or also flanged onto each other.
[0095] As the material from which the pipe pieces ( 1 , 2 , 3 , 4 , 5 ) can be produced, metals, ceramics, or plastics can be used.
[0096] It is especially preferred that the supply line parts ( 1 ) and the return line parts ( 2 ) are made from flexible hoses or corrugated boots, while the T-pieces ( 3 ) and the L-pieces ( 4 ) are made from a rigid material, such as rigid plastic, a ceramic, or metal or a combination of these materials, and the heat exchangers are made from metal, preferably copper, and/or a ceramic having a high heat conductivity value.
[0097] One of the modules of the device comprises the two L-pieces ( 4 ) and a heat exchanger ( 5 ). All of the other modules of the device each comprise two T-pieces ( 3 ) and a heat exchanger ( 5 ). If the modules are connected in a detachable way to the supply line parts ( 1 ) and the return line parts ( 2 ), an additional module can easily be joined to another supply line part ( 1 ) and a return line part ( 2 ).
[0098] The LED lamp to be temperature-controlled or the LED modules of the LED lamp to be temperature-controlled can be connected to each heat exchanger ( 5 ), so that connections having good heat conduction can be formed between the heat exchangers ( 5 ) and the LED lamp or the LED modules. The outer dimensions of the heat exchangers ( 5 ) are adapted to the geometry of the LED lamp or the LED modules.
[0099] The size of the device, in particular the size of the heat exchangers ( 5 ), the spacing of the T-pieces ( 3 ) and L-pieces ( 4 ), and the diameters of the supply line parts ( 1 ) and the return line parts ( 2 ) are adapted to the size of the LED lamp or the LED modules and to their purposes.
[0100] A fluid for controlling the temperature of the heat exchangers ( 5 ) and thus the LED lamp or the LED modules is guided through the pipes ( 1 , 2 , 3 , 4 , 5 ) that are connected to each other in a fluid-tight manner. The outlined arrows show the direction of flow of the fluid in the pipes ( 1 , 2 , 3 , 4 , 5 ). This fluid is a gas, for example compressed air or nitrogen, or a liquid, for example water, which transports the thermal energy away from the heat exchangers ( 5 ) or to the heat exchangers ( 5 ).
[0101] The return line ( 2 ) can also lead away from the supply in the opposite direction. Then, the return line ( 2 ) would be mounted reversed, that is the L-piece of the return line ( 2 ) would be mounted on the first T-piece (in the direction of flow of the fluid) of the supply line ( 1 ) and the L-piece of the supply line ( 1 ) would be mounted on the T-piece of the return line ( 2 ) that is connected, in the embodiment shown in FIG. 1 , to the first T-piece of the supply line ( 1 ). The direction of flow of the fluid would then no longer reverse from the supply line ( 1 ) to the return line ( 2 ).
[0102] FIG. 2 shows a ring-shaped heat exchanger ( 15 ) having a cross section of a six-sided polygon (hexagon). The heat exchanger ( 15 ) comprises two connection ports ( 16 ) through which the fluid can be guided through the heat exchanger ( 15 ), as indicated by the outlined arrows. The connection port ( 16 ) of the supply is located at the left, that of the return at the right. A partitioning wall in the form of a wedge ( 17 ) separates the supply from the return in the heat exchanger ( 15 ). The fluid therefore flows around the axis of the heat exchanger ( 15 ) clockwise in a circular motion, as indicated by the outlined arrows. The flow is close to the outer surface ( 18 ) of the heat exchanger ( 15 ), whereby a good heat transfer is achieved.
[0103] The inner ring of the heat exchanger ( 15 ) offers sufficient space for connecting T-pieces or L-pieces and for passing through cables and hoses (such as a supply line and a return line).
[0104] FIG. 3 shows, in a perspective view, the schematic structure of an arrangement of four heat exchangers ( 15 ) connected in such a way to form a device according to the invention, together with the supply line ( 21 ) and the return line ( 22 ), as well as the T-pieces ( 23 ) and the two L-pieces ( 24 ). The T-pieces ( 23 ) are arranged in the supply line ( 21 ) and the return line ( 22 ), while the two L-pieces ( 24 ) are each arranged on one of the ends of the supply line ( 21 ) and the return line ( 22 ). The supply line ( 21 ) and the return line ( 22 ) are connected to each other in a fluid-tight manner by the heat exchangers ( 15 ).
[0105] The two connection ports ( 16 ) are connected with T-pieces or L-pieces to the common supply line ( 21 ) (supply) or return line ( 22 ) (return) of a temperature-control system, such that several such heat exchangers ( 15 ), which can be arranged spatially one behind the other, can be supplied in parallel.
[0106] FIG. 3 shows, as an example, the structure of a cooling system for a high-power LED lamp, which is based on a parallel connection for the cooling medium supply and whose heat exchangers ( 15 ) or LED modules acting as cooling bodies are located one behind the other. Up to the last cooling body ( 15 ) (top right at the edge of the Fig.), the supply lines ( 21 ) or return lines ( 22 ) of the cooling bodies ( 15 ) are connected by T-pieces ( 23 ) to a common supply line ( 21 ) or return line/supply line ( 22 ). The last cooling body ( 15 ) is connected to this supply line by L-pieces ( 24 ). Such connectors ( 23 , 24 ) can be individual connection elements, which are connected, for example, by hoses and hose clamps to the cooling bodies ( 15 ). They could also be pluggable couplings, which seal by O-rings, or else lines integrated directly in the cooling bodies ( 15 ) with the same function, which are contacted from the ends (for example by plug-in connectors). The common main lines ( 21 , 22 ) can be rigid or flexible, for example polyamide hoses.
[0107] If LEDs (not shown) are mounted on the outer surfaces ( 18 ), a cylindrical LED lamp is then realized with which, by suitable selection of the LEDs, a pipe can be cured or rehabilitated. The current supply lines for the LEDs can also be guided through the ring opening of the heat exchangers ( 15 ).
[0108] Each heat exchanger ( 15 ), which is equipped on all of its outer sides with LEDs, is then an LED module. The coupling of the LED modules with cables for connecting the LED modules to a current supply produces an LED lamp.
[0109] The LED lamp is then, in the sense of the present invention, for example, a light source for pipe rehabilitation in the field of household connections.
[0110] FIG. 4 shows an LED module ( 30 ) of such an LED lamp in a schematic cross-sectional view. On an 8-sided cooling body ( 31 ) that here functions as a heat exchanger, a plurality of LEDs ( 32 ) is mounted using chip-on-board technology (COB technology). Here, several LEDs ( 32 ) are mounted on a substrate ( 33 ), wherein a substrate ( 33 ) is arranged on each of the eight sides of the cooling body ( 31 ). The LED module ( 30 ) is surrounded with a circular housing ( 34 ) in the form of protective glass, which is connected rigidly to the LEDs ( 32 ) or the cooling body ( 31 ).
[0111] The geometry of the LED module ( 30 ) is designed for a uniform illumination of a cylindrical hollow body, so that the inner walls of this hollow body are homogeneously irradiated by the LED module ( 30 ), even if the hollow body has a slightly larger diameter than that of the LED module ( 30 ). Such a light source is required, for example, in pipe rehabilitation. For applications having strict requirements for the optical output power, in which, due to the typical efficiencies of the LEDs ( 32 ) in the range of 1% to 50%, considerable amounts of heat must be dissipated through the cooling body ( 31 ), liquid cooling media are required as the fluid flowing through the cooling bodies ( 31 ). In the present case, this flow is circular around the axis of the cooling body ( 31 ).
[0112] The circulating flow is close to the surface of the cooling body ( 31 ), so that the substrates ( 33 ) mounted on this body can be cooled effectively.
[0113] The shown cross section thus shows the cross section of an LED module ( 30 ) of an LED lamp comprising several LED modules ( 30 ) together with a heat exchanger module ( 31 ) of the cooling device, that is an LED module ( 30 ) and a heat exchanger ( 31 ) in the sense of the present invention. The LED lamp can also comprise electrical connections (not shown), which are required for operating the LEDs ( 32 ), and a controller (not shown), which supplies the LEDs ( 32 ) with power and optionally controls the drive of the system. The device according to the invention can be just the cooling system or also the cooling system together with the LED lamp.
[0114] FIG. 5 shows schematically and as an example a modular LED structure. The shown LED lamp ( 40 ) consists of four cylindrical LED modules ( 41 ), whose geometry is adapted to the purpose of the application, having connection units ( 42 ) at which supply lines ( 43 ) are connected to the LED modules ( 41 ). An LED module ( 41 ) comprises at least one substrate having one or more LEDs that are mounted on a cooling body. As the cooling medium for cooling the LEDs, gases or liquids are used. The cooling body can be produced in different ways (for example milling, stamping, cutting, folding, eutectic bonding of metals, etc.). The LED modules ( 41 ) are enclosed in a housing (glass cylinder, stainless steel or plastic housing, etc.).
[0115] Furthermore, sensors (not shown), such as temperature, illuminance, current, or voltage sensors, can be integrated in the LED modules ( 41 ), wherein these sensors report the operating status to a control and supply unit ( 44 ), allowing the operating conditions of the LED lamp ( 40 ) to be adapted to the current state. The connection units ( 42 ) allow a modular expansion having additional LED modules ( 41 ), as well as exchangeability for maintenance purposes. From the viewpoint of the cooling circuit, the parallel supply of the LED modules ( 41 ) with the cooling medium is advantageous, in particular also in the sense of expandability, because all cooling bodies are always supplied with the same advance temperature. The LED modules ( 41 ) can be coupled by rigid or flexible connection elements, so that they are arranged in series with each other either rigidly or flexibly (by a protective hose, metal springs, corrugated boots, or the like). In this way, the LED lamp ( 40 ) can be pulled along an arc-shaped path in a pipe. A flexible or rigid supply line ( 43 ) connects the LED modules ( 41 ) to the control and supply unit ( 44 ), which includes the electrical supply and the supply with the cooling medium, as well as a control and regulation unit for the targeted control of relevant operating parameters.
[0116] The devices according to the invention are particularly suitable for use in pipe rehabilitation in the field of household connections (DN50-DN300, typically DN120-DN160). In addition, in this field, the use of the technology is also conceivable for larger pipe diameters, because the system allows high outputs and the geometric size can be scaled up. Other fields of application could also be down pipes for rain gutters, chimneys, or the like. An LED lamp could also be developed to rehabilitate side connections that are sealed by the light curing of so-called (liner) caps. Other applications are also conceivable, for example, the illumination of tubular spaces or hollow bodies.
[0117] The possibility of realizing a correspondingly constructed heating system is also possible. With this heating system, flexibly coupled heating elements (heating medium flowing through heating bodies) can heat the walls of cylindrical bodies. This can be realized either through radiant flux (thermal radiation) or through direct thermal conduction between the heating bodies and cylindrical bodies where they are in contact.
[0118] The features of the invention disclosed in the preceding description, as well as in the claims, Figures, and embodiments, can also be essential either alone or in any arbitrary combination for the realization of the invention in its various constructions.
[0119] It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. | A device and method are provided for controlling the temperature, in particular for cooling, of an LED lamp or LED modules of an LED lamp, e.g., for curing a light-cured pipe. The device includes: a fluid supply line and multiple heat exchangers connected to the supply line; multiple LEDs coupled to each heat exchanger with respect to heat transfer; and a fluid return line. The fluid supply and return lines are connected to each other in a fluid-tight manner by various combinations of L-pieces and T-pieces in or at the ends of the fluid supply and the return lines, so that the fluid flows from the LEDs in a spatially separated way and the fluid supply and return lines have at least two parallel fluid connections to each other, the heat exchangers being arranged in the fluid connections or constituting the fluid connections. | 5 |
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
[0001] The invention relates to a steam iron such as those with external steam supply, a handle, a switch for actuating a steam valve on a steam accumulator, a power supply for an electrical resistance heater, a steam tube, an iron base with a temperature-selection switch, a soleplate with a steam-supply connector, and a steam duct with at least one steam-outlet nozzle.
[0002] Steam irons with an external steam supply are known. This steam supply takes place via a steam accumulator disposed in the immediate vicinity of the steam iron and filled with superheated steam, for example a steam boiler, a steam line or a steam flask, on which a solenoid valve is connected. The pressure in the container is between 2.5 and 6 bar and the customary steam-tube length is approximately 2 m to 2.50 m. The solenoid valve is connected to a switch on the iron so that, when the switch is actuated, the solenoid valve opens and steam flows out of the steam accumulator, through the steam tube, into the steam iron, where it passes out of openings in the soleplate.
[0003] A known disadvantage of prior-art steam irons is that they leak water from the openings as well as steam. This water is extremely undesirable because it may contain particles of dirt. If a person using the steam iron has not taken any appropriate precautionary measures, the material that is to be ironed is permanently soiled and damaged. Possible reasons for water passing from the openings of the soleplate of the steam iron are a non-sealed solenoid valve, excessively low steam temperatures, cold, excessively long steam tubes, and a cold steam iron.
SUMMARY OF THE INVENTION
[0004] It is accordingly an object of the invention to provide a steam iron that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that does not spray water in any operating state.
[0005] With the foregoing and other objects in view, there is provided, in accordance with the invention, a steam iron. The steam iron includes an electrical resistance heater being able to connect to a power supply that powers the electrical resistance heater. The steam iron also has an iron base. A soleplate is connected to the base. A steam-supply connector is located on the soleplate. A steam duct with at least one steam-outlet opening is connected to the steam-supply connector. A steam dryer with a separate housing connects to an external steam supply.
[0006] The inventive steam iron with external steam supply includes an iron base with a soleplate. The soleplate is heated via an electrical resistance heater. A handle includes a switch for actuating a steam valve on a steam accumulator that is filled with superheated steam. Actuation of the switch routes steam from the steam accumulator, through a steam tube, to the steam iron. Because the steam iron is provided with a steam dryer to with a separate external or integrated housing, it is ensured that only dry steam passes into the steam iron. Any moist steam that may possibly be fed to the steam dryer is converted into dry steam again in the housing.
[0007] A further advantage of the inventive steam iron resides in the possibility of increasing the permissible length of a steam tube because any steam that may possibly be condensed in the steam tube can now be evaporated again in the steam dryer. The result is that the selected tube length is not at all critical as far as the functioning of the steam iron is concerned. It is easily possible, for example, to realize steam tubes of lengths of approximately five meters (˜5 m) without any disruption to operation occurring, that is to say without a steam iron connected thereto leaking water.
[0008] In the case of a particularly preferred embodiment, the steam dryer has a housing with a steam-connection stub for the steam tube, a collecting device for water droplets, and an inner steam inlet that opens out into a connection element that is connected to the steam-supply connector of the soleplate of the steam iron. The heatable steam dryer converts water into steam again. The configuration of the inner steam inlet, extending in the housing of the steam dryer with its opening in the upward direction, separates water contained in the moist steam and collects the water on the housing base. Therefore, the housing base is acting as a collecting device, where it is evaporated again by the heating of the steam dryer. The result is that only dry steam passes through the steam inlet into the steam iron.
[0009] According to an advantageous embodiment of the subject matter of the invention, the housing is disposed in the rear region, directly on the soleplate of a steam iron. This configuration firstly provides the advantage that the proximity of the housing to the steam iron results in dried steam no longer being able to condense again en route from the housing into the steam iron. In addition, the electrical energy for a conceivable active electrical resistance heater of the steam dryer can easily be derived from the supply of power to the steam iron.
[0010] According to a particularly preferred embodiment of the invention, the housing is produced from material with good heat conduction, for example copper, and, in its bottom region, has a contact surface for contact with the soleplate of the steam iron. This configuration allows the steam dryer to be heated via direct heat conduction from the soleplate into the housing. Accordingly, “good heat conduction” means great enough heat conduction that enough heat from the sole plate is transferred to the housing to cause trapped water to be evaporated to steam. Therefore, the steam dryer can be heated passively from the soleplate, rather than requiring its own electrical resistance heater. Such a soleplate operates at operating temperatures of approximately 220° C., which is quite sufficient for converting even relatively large quantities of water collecting in the housing into steam again.
[0011] The steam inlet of the steam dryer is advantageously constructed as a steam snorkel, which, by way of its part that leads into the connection stub, is disposed directly adjacent to the contact surface of the housing for contact with the soleplate of the steam iron. This results in optimum heat conduction without any obstruction by any possible air gaps. Dry steam passing into the steam snorkel through the snorkel opening is thus heated further, by heat from the soleplate, en route through the steam snorkel, with the result that the operational reliability of the steam iron is further increased. On the other hand, the dry steam flowing through the steam snorkel heats the steam snorkel, which runs in the base region of the steam dryer. This results in a further contribution to the evaporation of the condensation collected there.
[0012] A particularly advantageous embodiment of the inventive steam iron has a steam-drier connection stub. The steam-drier connection stub has a part extending into the housing. The steam-drier connection stub is provided with a sintered-metal attachment through which steam that is fed from the steam tube. This steam may possibly be moist and can be introduced into the housing such that dry steam and liquid water components separate from one another even in the sintered-metal attachment. After separation, the liquid water components drip off and can collect on the base of the housing without them being entrained by the flow of steam. The waste heat from the soleplate of the steam iron and from the steam snorkel heated up by the flowing steam ensure that this water, which has been separated off is evaporated effectively.
[0013] In the case of a particularly advantageous configuration of the inventive steam iron, a hollow screw is inserted into the original steam-supply connector, around which the connection element of the housing extends. The original steam-supply connector can be secured on the soleplate of the steam iron via a closure screw, which can be screwed into the hollow screw. Such a construction makes it possible for commercially available steam irons with an external steam supply to be retrofitted extremely easily with a steam dryer without any further technical changes being necessary. In order to protect a person using the steam iron, the steam dryer is preferably enclosed by a protective cap, with the result that any risk of causing burns is also minimized.
[0014] According to a further preferred embodiment of the invention, the steam iron is provided with a steam dryer at the factory. The steam dryer can be integrated in a base housing such that it cannot be seen from the outside. To integrate the steam dryer in the base, the housing merely has to be extended to the rear. An air gap between the base housing and the housing of the steam dryer also results in a separate protective cap possibly being dispensed, because the air gap ensures a sufficiently high level of heat insulation.
[0015] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0016] Although the invention is illustrated and described herein as embodied in a steam iron, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0017] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] [0018]FIG. 1 is a diagrammatic partially-sectional, right-side elevational view showing a steam iron;
[0019] [0019]FIG. 2 is a partially-sectional, rear elevational view of a steam dryer; and
[0020] [0020]FIG. 3 is a view similar to FIG. 1 showing a steam iron with an integrated steam dryer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a steam iron 1 . The steam iron 1 includes a base 24 , 25 , with a soleplate 2 , as well as a handle 17 and a switch 5 . The switch 5 is disposed adjacent the handle 17 and is for actuating a solenoid valve on a container which is filled with superheated steam, but is not illustrated in the drawing. The steam iron 1 is provided with an electrical resistance heater 30 and is supplied with power via a power-supply line 3 . The handle 17 is fastened on the base 24 , 25 of the steam iron 1 via fastening screws 23 , and a temperature-selection switch 19 is disposed between two fastening screws 23 . The steam tube 4 of an external steam supply, which was originally connected directly to a conventional steam iron according to the prior art, is fastened on a connection stub 8 , which is screwed in by way of a thread in a soldered-in nut 13 of the housing 14 of the steam dryer 7 . The connection stub 8 may also be fastened in some other releasable or non-releasable manner, for example by being soldered directly onto the housing 14 .
[0022] At its end directed into the interior of the housing 14 , the connection stub 8 is provided with a sintered-metal attachment 6 which, by virtue of its large surface area, helps moisture which is located in the steam to condense there and initially to drip off as water droplets onto the container base and to collect there. The dry steam supplied can spread without obstruction in the interior of the housing 14 . The flow pressure causes the dry steam to flow first through the snorkel opening 22 into the steam snorkel 11 , then into the connection element 18 , and through the hollow screw 9 to the steam supply connector 28 of the soleplate 2 . A steam duct 29 distributes the steam to at least one steam-outlet openings 20 beneath the soleplate 2 .
[0023] The housing 14 of the steam dryer 7 is configured as a pressureless hollow body made of material with good heat conduction, for example copper, with a volume of, for example, 50 cm 3 . Located in the housing 14 is a steam snorkel 11 , which is constructed as a curved tube and has a rectilinear subsection located directly on the base of the housing 14 and terminates, by way of its snorkel opening 22 , in the top 27 of the housing 14 . This steam snorkel 11 receives the dry steam and leads it via the connection element 18 , through the hollow screw 9 , directly into the soleplate 2 of the steam iron 1 .
[0024] The housing 14 has a contact surface 21 butting against the soleplate 2 of the steam iron 1 , over the entire width and over much of the height of said soleplate. This achieves a direct transfer of heat from the soleplate 2 into the housing 14 . In order to improve the transfer of heat, the steam snorkel 11 is also disposed directly on the wall or the base of the housing 14 of the steam dryer 7 , approximately parallel to the contact surface 21 . By configuring the steam snorkel 11 in this manner, the steam snorkel 11 is also heated in addition by a direct transfer of heat from the soleplate 2 of the steam iron 1 in addition to being heated by the flowing dry steam.
[0025] An embodiment of the invention which is conceivable but is not illustrated in the drawing is one in which one side of the housing wall simultaneously forms part of the wall of the steam snorkel 11 . The configuration ensures an even more efficient functioning of the steam dryer.
[0026] The water collected in the housing 14 is quickly evaporated again by the waste heat from the steam iron 1 and the position of the steam snorkel 11 in the container. This configuration ensures that only absolutely dry steam passes into the steam iron 1 during operation.
[0027] The steam dryer 7 is disposed on a conventional steam iron 1 provided with an external steam supply by directly screwing the hollow screw 9 into the original feed line of the soleplate 2 of the steam iron 1 . Simultaneously, the steam dryer 7 is placed in position by way of its connection element 18 . The connection element 18 encloses the hollow screw 9 on the outside. A closure screw 12 , which can be screwed into an end thread of the hollow screw, firmly fixes the housing 14 onto the soleplate 2 of the steam iron 1 .
[0028] In the case of steam irons 1 with the soleplate 2 projecting to the rear 26 , a correspondingly modified steam dryer 7 may also be similarly fastened on such a soleplate 2 from above. In order to protect the user against being burned and to protect against heat losses, the steam dryer 7 is provided with a protective cap 16 that encloses the housing 14 .
[0029] One embodiment of the steam iron 1 , as is illustrated in FIG. 3, is provided with a base 25 that integrates the housing 14 . The chromium housing of the base encloses the housing 14 of the steam dryer 7 at the top, sides and rear, and is spaced apart from the same. In a downward direction, the base 25 is of open configuration in the region of the steam dryer 7 , although it could also be of closed construction. The spacing between the housing 14 of the steam dryer and the walls of the base 25 produces an air gap 26 , which serves as heat insulation and also as protection against burns. In addition, it would also be possible for the air gap 26 to be filled with insulation material, in order for the heat losses to be reduced further. | A steam iron with external steam supply, has a handle, a switch for actuating a steam valve on a steam accumulator, a power supply for an electrical resistance heater, a steam tube, an iron base with a temperature-selection switch, a soleplate with a steam-supply connector, and a steam duct with at least one steam-outlet nozzle. The steam iron does not leak water during operation. To prevent spitting, the steam iron includes a steam dryer with a separate external or integrated housing. | 3 |
RELATED APPLICATION DATA
[0001] This application is a divisional of U.S. patent application Ser. No. 10/199,447 filed Jul. 18, 2002, now pending.
FIELD OF THE INVENTION
[0002] The invention relates to the field of sterilization containers used for the sterilization of medical devices. In particular, the invention pertains to a filter retention system used with sterilization containers.
BACKGROUND OF THE INVENTION
[0003] Prior to medical and surgical procedures or treatments, sterilization of medical devices and instruments prior to their use is necessary to reduce the risk of infection from microbes on such equipment. Various sterilization techniques are utilized in the medical field, such as irradiation of equipment, treatment using antimicrobial solutions, and temperature sterilization techniques. One of the most commonly employed techniques is sterilization using an autoclave, which involves placement of the equipment to be sterilized within a chamber which is subsequently heated to a temperature and for a time period sufficient to kill microbial agents which can be present on the equipment.
[0004] Sterilization containers are sometimes used to house surgical instruments and other devices to be sterilized. Typical sterilization containers are constructed of a lid and base portion, and a vent portion located on the lid, base or both. The vent portion permits the movement of gases to accommodate the changes in pressure created by increasing or decreasing temperatures of the internal and external environments of the container. In order to prevent contamination by the handling and storage of sterilization containers, filters can be positioned in relation to the vent portion to permit the transport of gases but reduce or prevent the transport of microbes.
[0005] Filter systems for sterilization containers have been developed. Typical filter systems include a filter retainer and an associated locking mechanism to secure the filter in place relative to the vent portion of the container. Such a filter retention system is described in Nalepa et al. U.S. Pat. No. 5,968,459, which describes a filter retention system including a rotating locking plate which secures a filter retaining plate and filter to a sterilization container having vent openings. One drawback of this system, however, is that it requires a turning or pivoting movement by the user's hand, and does not provide a penetration resistant structure to protect the filter from piercing. Another filter system is described in Spence U.S. Pat. No. 4,783,321, which discloses a penetration resistant filter retaining system having an upper retainer disc and lower retainer disc. This system, however, requires precise positioning of the retainer discs in relation to one another and the vent openings, and does not contain a single, centrally located locking mechanism.
[0006] There is a need for improved filter systems useful for sterilization containers that facilitate the filter retention function of the container while maintaining the properties required for sterilization processes. There is a further need for filter systems which secure a filter onto a sterilization container, protect the filter from damage or unintended movement, and reduce the likelihood of contamination both during and following sterilization. There is yet a further need for filter systems which are ergonomic and afford the user a comfortable assembly and preparation, especially when such activities are repeated tasks.
SUMMARY OF THE INVENTION
[0007] The invention provides a filter system for sterilization containers comprising a locking mechanism that is comfortable and easy to use and that requires a simple sliding movement of the users hand to lock and unlock the filter. It has further been discovered that a filter system can be constructed to reduce or eliminate the need for precise positioning of filter components in relation to one another by the user to prevent the likelihood of physical puncture of the filter while at the same time permitting the unobstructed transport of air across the filter layer. The filter system of the invention is also relatively easy to manufacture. The filter system of the invention also does not require the use of gaskets circumscribing the perimeter of the system. The invention is particularly useful in a variety of medical applications wherein sterilization of medical devices and instruments is needed for a surgical treatment or procedure.
[0008] The invention provides a filter system for a sterilization container having a lid, base and vented portion, said filter system comprising:
[0009] a first filter retention plate adapted for positioning and retaining a filter over a vented portion of said container;
[0010] a second filter protective plate adapted for positioning between said filter and said vented portion of said container;
[0011] wherein each of said first plate, second plate, and filter is adapted to align with and be positioned in relation to a central pin extending outward from said vented portion of said container; and
[0012] a locking mechanism adapted to secure said first plate, second plate and filter onto said container, said locking mechanism comprising a locking plate adapted for linear sliding movement in a direction substantially parallel to the surface of said first plate.
[0013] The invention further provides a locking mechanism for a sterilization container filter system having a vented portion, said locking mechanism comprising:
[0014] a first filter retention plate;
[0015] a locking plate having an elongate opening and attached to the upper surface of said first filter retention plate, and adapted for linear sliding movement in a direction substantially parallel to the surface of said plate;
[0016] wherein said locking plate is adapted to cooperate with a central pin extending outward from a vented portion of the sterilization container; and
[0017] wherein linear sliding movement of said locking plate increases the vertical compressive force between the filter system components.
[0018] The invention also provides a filter system for a sterilization container having a vented portion comprising a plurality of openings, said filter system comprising:
[0019] a first filter retention plate comprising a plurality of openings;
[0020] a second protective plate comprising a plurality of openings;
[0021] wherein said first filter retention plate and second protective plate are adapted to accommodate and retain a gas-permeable filter therebetween; and
[0022] wherein each of said first retention plate and second protective plate are structured so that the openings thereof and said openings of said vented portion are arranged to permit substantially unobstructed movement of air across said filter while forming a barrier to transverse physical perforation of said filter, said openings maintaining such barrier irrespective of rotational positioning of said plates relative to a central axis.
[0023] The invention further provides a filter system for a sterilization container having a vented portion comprising a plurality of openings, said filter system comprising:
[0024] a first filter retention plate comprising a plurality of openings;
[0025] a second protective plate comprising a plurality of openings;
[0026] wherein said first filter retention plate and second protective plate are adapted to accommodate and retain a gas-permeable filter therebetween; and
[0027] wherein each of said first retention plate and second protective plate are structured so that the openings thereof and said openings of said vented portion are arranged to permit substantially unobstructed movement of gases across said filter while forming a barrier to transverse physical perforation of said filter, said openings maintaining such barrier irrespective of rotational positioning of said plates relative to a central axis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] [0028]FIG. 1 is an angled side view of a sterilization container showing the lid and filter assembly attached thereto and the base portion separated from the lid according to one embodiment of the invention.
[0029] [0029]FIG. 2 is an exploded view of a sterilization container lid with the filter system components separated and including a filter according to one embodiment of the invention.
[0030] [0030]FIG. 3A is an angled side view of the top of the retention plate showing the locking mechanism in the locked position according to one embodiment of the invention.
[0031] [0031]FIG. 3B is an angled side view of the top of the retention plate showing the locking mechanism in the unlocked position according to one embodiment of the invention.
[0032] [0032]FIG. 4 is a top view of the locking plate component of the locking mechanism according to one embodiment of the invention.
[0033] [0033]FIG. 5 is a side view of the locking plate component of the locking mechanism according to one embodiment of the invention.
[0034] [0034]FIG. 6 is a bottom view of the locking plate component of the locking mechanism according to one embodiment of the invention.
[0035] [0035]FIG. 7 is an exploded angled side view of the filter system showing separated components and alignment of openings thereof, including a transparent cut-away view of the second protective plate positioned on a cut-away vented portion of the lid, in accordance with one embodiment of the invention.
[0036] [0036]FIG. 8 is an angled top view of a first filter retention plate in accordance with one embodiment of the invention.
[0037] [0037]FIG. 9 is an angled top view of a second protective plate in accordance with one embodiment of the invention.
[0038] [0038]FIG. 10 is a side view of the central locking pin according to one embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0039] As used herein, the term “plate” is meant to refer to a component having a substantially planar construction. The term is not intended to imply a limitation as to a particular perimeter configuration, such as a circular, disc-like shape.
[0040] In general, the filter system of the invention is designed for use as a component in a sterilization container. Suitable sterilization containers for use with the filter system of the invention can include a basic construction of a lid and base portion, wherein at least one of either the lid, the base, or both, contains a vented portion. For purposes of illustration, the invention is depicted in the drawings as having the filter system located on the lid, the lid containing the vented portion of the container. In a further embodiment, a sterilization container can be constructed to have more than one vented opening and corresponding filter system therewith. The filter system of the invention performs the overall function of securing a gas permeable filter over a vented portion of a sterilization container and maintaining the position of the filter to create a separate internal and external environment relative to the container throughout the sterilization process. The filter thus functions to permit the transport of air/gas across the filter membrane, while reducing or preventing migration of microbes therethrough.
[0041] Referring now to FIG. 2, the filter system components are shown in association with a sterilization container lid 10 . The vented portion 11 contains a plurality of vent openings 12 through the lid 10 , and the vent openings 12 are arranged to cooperate with a gas-permeable filter 100 and the filter plates such that when the filter system is completely assembled, all vent openings 12 of the container are covered by the filter. Referring now to FIG. 1, the lid of the sterilization container can be secured onto the base portion 90 by a securing mechanism (not shown), such as a latch. The securing mechanism can be structured to create a seal which prevents air flow at the lid-base juncture around the perimeter of the lid. One or both of the contacting surfaces of the lid and base can contain a gasket or seal completely circumscribing the contacting surface(s).
[0042] The basic sterilization container components can be composed of any medical grade material which can be used in autoclave sterilization. Typically, the basic sterilization container components are composed of stainless steel. Secondary components such as gaskets, washers, and the like, can be composed of any suitable sterilizable material, such as plastic. The various components of the invention can be manufactured using techniques, machining equipment, and materials readily available in the sterilization container manufacturing field.
[0043] By virtue of its structure, however, the filter system of the invention eliminates the need for gasket components between the plate components. Referring now to FIGS. 2 and 7, the outer boundary of the vented portion 11 of the lid 10 comprises a contiguous raised ring-like perimeter 13 circumscribing the entire vented portion 11 . The area immediately surrounding the center of the vented portion 11 also contains a contiguous central raised ring 14 . Referring now to FIGS. 2, 3A, 3 B and 8 , the periphery of the first filter retention plate 20 comprises a contiguous raised rim 21 which is structured to coordinate with the raised perimeter 13 surrounding the vented portion 1 . Accordingly, when the filter system is assembled and locked, a gasket-like seal is formed by the superimposing of the first filter retention plate rim 21 and the perimeter 13 at the vented portion 11 of the lid 10 . Referring now to FIGS. 2 and 9, the second protective plate 30 is held in place by the central raised ring 14 of the vented portion 11 . The central raised ring 14 of the vented portion 11 also cooperates with a corresponding central raised portion 22 on the first retention plate 20 which together also form a gasket-like seal.
[0044] The basic filter system components of the invention are shown in FIG. 2. The filter system generally comprises a first filter retention plate 20 and a second filter protective plate 30 which align in cooperation with a central pin 40 extending outward from the vented portion 11 of the container. The first filter retention plate 20 is adapted for positioning and retaining a filter 100 over the second protective plate 30 , which in turn is positioned to cover the vented portion 11 of the container. Thus, the second filter protective plate 30 is adapted to be positioned between the filter 100 and the vented portion 11 of the container. Each of the first retention plate 20 , second protective plate 30 , and filter 100 is sized to align overall in relation to a central axis (designated by the symbol “α”) and also to be in alignment with the central pin 40 extending outward from said vented portion 11 of the container.
[0045] Locking Mechanism
[0046] The filter system of the invention further comprises a locking mechanism adapted to secure said first retention plate 20 , filter, and second protective plate 30 onto the container. Referring now to FIGS. 3A, 3B, 4 , 5 and 6 , the locking mechanism comprises a locking plate 50 adapted for bi-directional linear sliding movement in a manner substantially parallel to the planar surfaces of the plates. The locking plate 50 is thus positioned substantially perpendicular relative to the longitudinal central axis a (see FIGS. 2 and 7) of the central pin 40 (as shown in FIGS. 2, 3A and 3 B).
[0047] Referring now to FIGS. 4, 5 and 6 , the locking plate comprises an elongate central opening 51 adapted to accommodate a portion of the central pin 40 therethrough. In one embodiment and as seen in FIG. 10, the top of the central pin 40 is widened or tapered to form a “head” 41 , the cross-sectional diameter of which is larger than the medial region of the central pin 40 . Again referring to FIGS. 4 and 6, one end of the elongate central opening 51 is slightly wider than the other to exclusively accommodate the head 41 of the central pin 40 , and the remainder of the elongate central opening 51 is relatively narrower to prevent vertical separation of the central pin 40 from the locking plate 50 by “trapping” the locking plate 50 between the head 41 of the central pin 40 and the upper surface of the first retention plate 20 .
[0048] To further stabilize the operation of the locking mechanism, the locking mechanism can further comprise stabilization means. In one embodiment, stabilization means can include at least one additional pin-and-slot structure. As can be seen in FIGS. 2, 3A and 3 B, the first filter retention plate 20 further comprises at least one guide pin, preferably two guide pins, 52 a and 52 b respectively, which are adapted to cooperate with at least one corresponding elongate guide opening (illustrated as two elongate guide openings 53 a and 53 b respectively) in the locking plate 50 . Accordingly, undesired rotational or pivoting movement of the locking plate relative to the first retention plate is reduced or eliminated by the stabilization means.
[0049] A variety of stabilization means can be used in accordance with the invention. Examples of suitable stabilization means include, but are not limited to, interfitting brackets, toe-in-slot structures, nub-and-groove structures, and the like.
[0050] The locking plate 50 can further comprise at least one sliding tab 60 to facilitate manual operation of the locking mechanism 50 . The user can easily lock and unlock the locking mechanism by a simple linear sliding movement of the fingers and hand positioned on the sliding tab 60 . FIGS. 3A and 3B together illustrate the locked and unlocked positions, respectively, of the locking mechanism. Generally, one of the advantages of the structure of the locking mechanism of the invention is its ease of use. In other words, the locking and unlocking of the locking mechanism does not require awkward, turning or contorting hand movements to operate.
[0051] Once the filter system components are stacked and aligned with the central pin 40 , the movement of the locking mechanism from the unlocked to the locked positions increases the vertical compressive force between the components. Referring now to FIGS. 4, 5 and 6 , one embodiment of such a locking mechanism structure is shown. The region of the locking plate 50 immediately adjacent to each narrower side of the elongate central opening 51 comprises an elevated ramp 56 adapted to interact with the head 41 of the central pin 40 . This interaction “traps” the locking plate 50 between the underside of the head 41 and the upper surface of the first retention plate 20 and increases the vertical pressure between the filter system components.
[0052] The locking mechanism of the invention can further comprise an intermediate plate 70 (see FIG. 2) to be positioned between the underside of the locking plate 50 and the upper surface of the first retention plate 20 . The intermediate plate 70 is preferably composed of a sterilizable resilient material, such as plastic. The intermediate plate 70 functions to place a less rigid material between the rigid components in order to better slide the rigid components together.
[0053] The central pin 40 can be permanently fixed to the center of the vent opening 11 of the container using a self-locking retaining ring 95 , for example, which can engage central pin recess 42 (see FIG. 10). The locking plate 50 can be permanently but movably attached to the first retention plate 20 , positioned to accommodate the central pin 40 through the elongate central opening 51 of the locking plate 50 . The guide pin(s) 52 a and 52 b can be permanently attached to the first retention plate 20 . When two guide pins are used, they are preferably located on opposing sides of the elongate central opening 51 . The top end of each guide pin can have a head which is wider than the remainder of the guide pin to prevent inadvertent vertical separation of the locking plate 50 from the first retention plate 20 .
[0054] Filter System Opening Configuration
[0055] Another inventive aspect of the filter system of the invention is the structural relationship among the openings of the filter system components. The structure, arrangement and orientation of the openings of each are illustrated in FIG. 7. The vent openings 12 , first retention plate openings 25 and second protective plate openings 35 , by virtue of their structure and arrangement, are arranged such that when a filter (see FIG. 2) is placed within the filter system, the plates permit substantially unobstructed movement of gases through from the containment interior to the exterior environment while at the same time permitting a physical barrier resistant to unintentional transverse penetration of the filter. Protection of the structural integrity of the filter is an important aspect of the invention, since rupturing the filter jeopardizes the biological containment of the interior environment, thereby compromising sterility of the components placed within the container.
[0056] Furthermore, the filter system components are constructed such that this functionality of the opening arrangement is maintained irrespective of the rotational positioning (relative to the central axis a) of the first plate 20 relative to the second plate 30 , as well as the relative positioning thereof with respect to the vent openings 12 on the container. In a preferred embodiment, the openings on both the first retention plate and second protective plate are elongate and arcuate, and coordinate to intermittently overlap one another such that at any give position relative to the central axis, an unobstructed opening between the two plates is formed. The region of the vent portion 11 between the vent openings 12 functions as the barrier to transverse physical penetration which would otherwise permit perforation of the filter at the vent opening locations.
[0057] At any given rotational position of the first retention plate 20 and second protective plate 30 relative to the container vent openings 12 , air exiting the container which passes outward through the vent opening 12 (by virtue, for example, of the pressure created during sterilization temperatures) is diverted in a lateral direction by the solid portion of the second protective plate 30 until it reaches an opening of the second protective plate 30 .
[0058] Referring now to FIGS. 7 and 9, both the upper and lower surfaces of the second protective plate 30 contain intermittent ridges 39 , illustrated as having an arcuate shape, which function to maintain a slight space between the first retention plate 20 and the planar surface of the second protective plate 30 with the filter (not shown) between, as well as a slight space between the second protective plate and the planar surface of the vented portion 11 of the container. Although depicted as arcs, a variety of other shapes and sizes of intermittent ridges can be used provided they accomplish the slight spacing between the plates and surfaces as described.
[0059] Again referring to FIG. 7, the gases passing through the second protective plate openings 35 then passes through the filter (not shown). The air continues to exit through the first retention plate openings 25 and exits into the external environment.
[0060] The first retention plate openings 25 and the second protective plate openings 35 are configured and dimensioned to provide overlapping regions at multiple locations with the filter inbetween. Thus, another advantage of the invention afforded to the user is that precise or specific positioning of the filter system components, aside from alignment over a central axis, is not necessary. The filter system performs its function(s) irrespective of the rotational alignment of the plates and vented portion of the container. Accordingly, the use and operation of the sterilization container is substantially simplified.
[0061] In one example of using the invention, a sterilization container lid is separated from the container base and the filter system components are disassembled—namely, the filter plates are removed from the vent portion of the lid. When the user is ready to seal the contents of the container to be sterilized, the user first places the second protective plate over the vented portion of the container. Then, the filter is placed over the second protective plate, followed by the first retention plate with the locking plate on the upper surface. Once the components are aligned with the central axis and the head of the central pin is protruding through the elongate central opening of the locking plate, the user simply slides the locking plate tab(s) to secure and compress the components together. Once the lid and base of the sterilization container are secured, the sterilization container and its contents can be subjected to the sterilization process, e.g. autoclaving.
[0062] Industrial Applicability
[0063] The filter system of the invention is useful in sterilization containers whenever control and separation between the internal and external environments is desired. The filter system of the invention is especially useful as part of the construction of autoclavable sterilization containers for sterilizing and containing medical devices and instruments in association with medical and surgical procedures.
[0064] The invention has been described with reference to various specific and preferred embodiments and techniques. It will be understood that reasonable variations and modifications to such specific and preferred embodiments and techniques can be made without departing from the spirit and scope of the invention. | The invention described herein relates to a filter system for sterilization containers which secures a gas permeable filter onto a vented portion of the container. The filter system of the invention includes a locking mechanism that is comfortable and easy to use, and that requires a simple sliding movement of the users hand to lock and unlock the filter system components in place. The invention further includes a filter system structured such that the openings of the filter system plates permit transport of air across the filter while at the same time the openings are arranged to reduce or prevent undesirable physical perforation of the filter. By virtue of its structure, the need for particular rotational positioning of filter components in relation to one another is significantly reduced. The filter system of the invention also reduces or eliminates the need for perimeter gaskets. The invention is useful in a variety of medical applications wherein sterilization of medical devices and instruments is associated with a surgical treatment or procedure. | 0 |
DESCRIPTION OF THE PRIOR ART
Compounds having a benzenesulphonamide chain have been described in Application EP 864 561 in relation to their NO-yielding character and their thromboxane A 2 (TXA 2 ) receptor antagonist character, as well as in Application EP 648 741 solely in relation to their TXA 2 receptor antagonist properties.
The compounds of the present invention have a novel structure giving them a TXA 2 receptor antagonist and 5HT 2 serotonergic receptor antagonist character.
BACKGROUND OF THE INVENTION
Platelet aggregation and vasospasms play an essential role in the etiology and development of atherothrombotic cardiovascular disorders. TXA 2 , an arachidonic acid metabolite, and serotonin (5HT), a neurotransmitter, are both powerful vasoconstrictor agents, and are able to induce or reinforce platelet activation, resulting in the aggregation thereof. The vasoconstrictor and pro-aggregation actions of TXA 2 are effected through the intermediary of membrane receptors called TP receptors (Medicinal Research Reviews, 1991, 11, 5, p. 503) while those of serotonin are effected via the intermediary of 5HT 1 or 5HT 2 receptors (T.I.P.S., 1991, 121, p. 223). Research strategies pursued with the aim of finding agents that block the production and/or activation of TXA 2 have led to the development of selective TP receptor antagonists, of TXA 2 -synthase inhibitors, or of mixed agents that exhibit both properties (Medicinal Research Reviews, ibid., T.I.P.S., 1991, 121, 158). Like TXA 2 , serotonin acts by stimulating platelets and vascular contractions and its activity is found to be increased in atherothrombotic disorders.
The idea of compounds that oppose both the process that causes thromboxane to become active and the process that causes serotonin to become active is extremely useful for the clinician. Such products have the advantage of offering more complete protection both against the activation of platelets and against vasospasms. It will thus be possible for such products to be used in the treatment of pathologies associated with increased activity of TXA 2 and 5-HT especially in the treatment of atherothrombotic cardiovascular disorders, such as myocardial infarction, angina pectoris, cerebral vascular accidents, Raynaud's disease, and also asthma and bronchospasms, as well as migraine and venous disorders.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to the compounds of formula (I):
wherein:
n is an integer of from 1 to 3 inclusive,
m is an integer of from 0 to 6 inclusive,
R a represents a hydroxy, linear or branched (C 1 -C 6 )alkoxy, aryloxy or arylalkyloxy group,
R 1 and R 2 represent independently a hydrogen atom, a halogen atom, an alkyl group, a linear or branched (C 1 -C 6 )alkoxy group, a hydroxy group or a linear or branched (C 1 -C 6 )perhaloalkyl group,
R 3 represents a hydrogen atom or an alkyl, arylalkyl, cycloalkylalkyl, aryl or cycloalkyl group,
T 1 represents an alkylene, O-alkylene, alkylene-O— or (C 1 -C 3 )alkylene-O—(C 1 -C 3 )-alkylene group,
G represents a G 1 - or G 1 -T 2 -A- group wherein:
A represents an aryl group,
T 2 represents a bond or an alkylene, —O-alkylene, alkylene-O— or (C 1 -C 3 )alkylene-O—(C 1 -C 3 )alkylene group,
G 1 represents a —NR 4 R 5 group wherein R 4 and R 5 represent independently a hydrogen atom, or an alkyl, cycloalkyl, optionally substituted aryl, optionally substituted arylalkyl, cycloalkylalkyl, optionally substituted heteroaryl or optionally substituted heteroarylalkyl group, or G 1 represents a heterocycloalkyl group of formula
having from 5 to 7 ring members, wherein Y represents a nitrogen atom, an oxygen atom or a CH or CH 2 group and R 6 represents a hydrogen atom or an alkyl, cycloalkyl, cycloalkylalkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted arylcarbonyl, optionally substituted arylcarbonylalkyl, optionally substituted diarylalkyl, optionally substituted diarylalkenyl, optionally substituted (aryl)(hydroxy)alkyl, optionally substituted heteroaryl, optionally substituted heteroarylalkyl, optionally substituted heteroarylcarbonyl or optionally substituted heteroarylcarbonylalkyl group,
to their enantiomers and diastereoisomers, and also to addition salts thereof with a pharmaceutically acceptable acid or base,
wherein:
the term “alkyl” denotes a linear or branched chain having from 1 to 6 carbon atoms,
the term “alkenyl” denotes a chain having from 2 to 6 carbon atoms and containing from 1 to 3 double bonds,
the term “alkylene” denotes a linear or branched divalent group containing from 1 to 6 carbon atoms, unless specified otherwise,
the term “cycloalkyl” denotes a saturated cyclic group containing from 3 to 8 carbon atoms,
the term “aryl” denotes a phenyl or naphthyl group,
the term “heteroaryl” denotes a mono- or bi-cyclic group having from 4 to 11 ring members that is unsaturated or partially saturated and contains from 1 to 5 hetero atoms selected from nitrogen, oxygen and sulphur,
the terms “diarylalkyl” and “diarylalkenyl” denote, respectively, alkyl and alkenyl groups as defined hereinbefore, substituted by two identical or different aryl groups as defined hereinbefore,
the term “substituted” relating to aryl, arylalkyl, arylcarbonyl, arylcarbonylalkyl, diarylalkyl, diarylalkenyl, heteroaryl, heteroarylalkyl, heteroarylcarbonyl and heteroarylcarbonylalkyl denotes that the groups in question are substituted in the aromatic moiety by one or more halogen atoms, alkyl groups, linear or branched (C 1 -C 6 )alkoxy groups, hydroxy groups, cyano groups, nitro groups or amino groups (optionally substituted by one or two alkyl groups), wherein the heteroaryl and heteroarylalkyl groups may also be substituted by an oxo group.
Amongst the pharmaceutically acceptable acids there may be mentioned, without implying any limitation, hydrochloric, hydrobromic, sulphuric, phosphonic, acetic, trifluoroacetic, lactic, pyruvic, malonic, succinic, glutaric, fumaric, tartaric, maleic, citric, ascorbic, methanesulphonic, camphoric acid, etc.
Amongst the pharmaceutically acceptable bases there may be mentioned, without implying any limitation, sodium hydroxide, potassium hydroxide, triethylamine, tert-butylamine etc.
Preferred compounds of the invention are those wherein n is 2.
Other preferred compounds of the invention are those wherein m is 2.
An advantageous embodiment of the invention relates to compounds of formula (I) wherein R 3 represents a hydrogen atom.
Another advantageous embodiment of the invention relates to compounds of formula (I) wherein R a represents a hydroxy group.
In the compounds of formula (I), G 1 preferably represents a heterocycloalkyl group of formula
There may be mentioned, for example, without implying any limitation, the groups piperidine, pyrrole, piperazine . . .
Advantageously, in the groups G 1 , R 6 represents a group selected from alkyl (for example methyl), arylcarbonyl (for example benzoyl), arylcarbonylalkyl (for example benzoyl-methyl), diarylalkenyl (for example bisphenylmethylene), (aryl)(hydroxy)alkyl (for example (phenyl)(hydroxy)methyl), aryl (for example phenyl), and heteroaryl, each of those groups being optionally substituted in their aromatic moiety where such a moiety is present. Advantageously, the substituent chosen will be a halogen atom or an alkoxy group.
Amongst the preferred heteroaryl groups there may be mentioned more especially the groups 1,2-benzisoxazole, 1,2-benzisothiazole, . . .
An especially advantageous embodiment of the invention relates to compounds of formula (I) wherein n and m are each 2, R a represents a hydroxy group, R 2 and R 3 each represents a hydrogen atom, R 1 represents a halogen atom, and G 1 represents a heterocycloalkyl group of formula
wherein Y represents a nitrogen atom or a —CH or CH 2 group, and R 6 is selected from the groups alkyl, arylcarbonyl, arylcarbonylalkyl, diarylalkenyl, (aryl)(hydroxy)alkyl, aryl and heteroaryl.
Amongst the preferred compounds of the invention there may be mentioned more especially 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-{2-[4-(6-fluoro-1,2-benzisothiazol-3-yl)-1 -piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid and 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-{[2-(4-methyl-1-piperazinyl)phenoxy]methyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid.
The present invention relates also to a process for the preparation of the compounds of formula (I), which process is characterised in that there is used as starting material a compound of formula (II):
wherein
n, m, R 1 , R 2 , R 3 and T 1 are as defined for formula (I),
R′ a represents a linear or branched (C 1 -C 6 )alkoxy group and
X 1 represents a leaving group (for example a halogen atom or a tosyl group),
which, when it is desired to obtain compounds of formula (I) wherein G represents a group G 1 as defined for formula (I), is treated in basic medium with a compound of formula G 1 H to yield a compound of formula (I/a):
a particular case of the compounds of formula (I) wherein m, n, R′ a , R 1 , R 2 , R 3 , T 1 and G 1 are as defined for formula (I),
or which, when it is desired to obtain compounds of formula (I) wherein G represents a group G 1 -T 2 -A- as defined for formula (I), is treated in basic medium with a compound of formula HO-T 2 -A-G R , wherein T 2 and A are as defined for formula (I) and G R represents a reactive group so selected that it can effect nucleophilic substitution of the leaving group X 1 present in the substrate to yield a compound of formula (IV):
wherein
m, n, R′ a , R 1 , R 2 , R 3 , T 1 , A and T 2 are as defined hereinbefore,
the hydroxy group of which is converted into a leaving group or into a halogen atom to yield a compound of formula (V):
wherein
m, n, R′ a , R 1 , R 2 , R 3 , T 1 , A and T 2 are as defined hereinbefore and
X 2 represents a leaving group (for example a halogen atom or a tosyl group),
which compound of formula (V) is treated in basic medium with a compound of formula G 1 H, G 1 being as defined for formula (I), to yield a compound of formula (I/b):
a particular case of the compounds of formula (I) wherein m, n, R′ a , R 1 , R 2 , R 3 , T 1 , T 2 , A and G 1 are as defined hereinbefore,
which compounds of formulae (I/a) and (I/b) may be subjected to hydrolysis of the ester function, in acid or basic medium according to the reactive groups present in the molecule, to yield a compound of formula (I/c):
a particular case of the compounds of formula (I) wherein m, n, R 1 , R 2 , R 3 and T 1 are as defined hereinbefore and G is as defined for formula (I),
which compounds (Ia), (I/b) and (I/c) constitute the totality of the compounds of formula (I), and:
may, if necessary, be purified according to a conventional purification technique,
are optionally separated into their stereoisomers according to a conventional separation technique,
are converted, if desired, into addition salts with a pharmaceutically acceptable acid or base,
wherein, at any moment considered appropriate during the course of the process described above, the carboxylic ester function —CO—R′ a may be hydrolysed to the corresponding acid, which may be converted again to a different ester as required by the synthesis.
The present invention relates also to pharmaceutical compositions comprising as active ingredient one compound of formula (I), on its own or in combination with one or more pharmaceutically acceptable, inert, non-toxic excipients or carriers.
Amongst the pharmaceutical compositions according to the invention there may be mentioned more especially those which are suitable for oral, parenteral or nasal administration, tablets or dragees, sublingual tablets, gelatin capsules, lozenges, suppositories, creams, ointments, dermal gels, etc.
The useful dosage varies in accordance with the age and weight of the patient, the nature and the severity of the disorder and also the administration route, which may be oral, nasal, rectal or parenteral. Generally, the unit dosage ranges from 0.1 mg to 500 mg for a treatment of from 1 to 3 administrations per 24 hours.
The following Examples illustrate the invention and do not limit it in any way.
The starting materials employed are known products or products prepared according to known procedures.
PREPARATION A
Methyl 3-(3-(bromomethyl)-6-{[(4-chlorophenyl)sulphonyl]amino}-5,6,7,8-tetrahydro-1-naphthyl)propanoate
Step a: Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-formyl-5,6,7,8-tetrahydro-1-naphthyl)propanoate
2.5 g of a solution of osmium tetroxide (2.5% by weight) in 2-methyl-2-propanol, and then 20 g of sodium periodate, are added at ambient temperature to a solution of 10 g (23 mmol) of methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-vinyl-5,6,7,8-tetrahydro-1-naphthyl)propanoate, described in Application EP 864 561, in a mixture of 100 ml of dioxan and 50 ml of water. After stirring for one night at ambient temperature, the solution is filtered and the filtrate is concentrated. The residue obtained is taken up in dichloromethane and washed with water, and the organic phase is dried and concentrated and then purified by chromatography on silica gel, using as eluant a cyclohexane/ethyl acetate mixture (60/40), to yield the expected compound.
Step b: Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-hydroxymethyl-5,6,7, 8-tetrahydro-1-naphthyl)propanoate
1 g (2.6 mmol) of sodium borohydride is added to a solution of 4 g (9.2 mmol) of the product described in the above Step in 100 ml of methanol. The reaction mixture is stirred for 30 minutes at ambient temperature. After the addition of a saturated aqueous solution of sodium hydrogen carbonate and evaporation of the majority of the methanol, the reaction mixture is extracted with dichloromethane. The organic phase is dried and concentrated. Purification by chromatography on silica gel, using as eluant an ethyl acetate/cyclohexane mixture (50/50), yields the expected product.
Step c: Methyl 3-(3-(bromomethyl)-6-{[(4-chlorophenyl)sulphonyl]amino}-5,6,7, 8-tetrahydro-1-naphthyl)propanoate
At ambient temperature, 2.23 g (8.5 mmol) of triphenylphosphine and then, slowly, a solution of 2.83 g (8.5 mmol) of carbon tetrabromide in 25 ml of dichloromethane, are added to a solution of 3.10 g (7.1 mmol) of the product described in the above Step in 50 ml of dichloromethane. After stirring at ambient temperature for one hour, the solvent is evaporated off. Purification by chromatography on silica gel, using as eluant a cyclohexane/ethyl acetate mixture (80/20), yields the expected product.
PREPARATION B
Methyl 3-(3-(3-bromopropyl)-6-{[(4-chlorophenyl)sulphonyl]amino}-5,6,7,8-tetrahydro-1-naphthyl)propanoate
Step a: Tert-butyl 3-(7-{[(4-chlorophenyl)sulphonyl]amino}-4-[2-(methoxycarbonyl)ethyl]-5,6,7,8-tetrahydro-1-naphthyl)-2-propenoate
1.25 g (4 mmol) of tri-o-tolylphosphine, 8.5 ml of triethylamine, 230 mg (1 mmol) of palladium acetate and 9 ml of tert-butyl acrylate are added to a solution of 10 g (20.5 nmol) of methyl 3-(3-bromo-6-{[(4-chlorophenyl)sulphonyl]amino}-5,6,7,8-tetrahydro-1-naphthyl)propanoate, described in Application EP 864 561, in 250 ml of DMF. The reaction mixture is stirred at 110° C. for 8 hours. The solvent is then evaporated off, and purification by chromatography on silica gel, using as eluant a cyclohexane/ethyl acetate mixture (80/20), yields the expected product.
Step b. Methyl 3-([3-(2-tert-butoxycarbonyl)ethyl]-6-{[(4-chlorophenyl)-sulphonyl]amino}-5,6,7,8-tetrahydro-1-naphthyl)propanoate 0.87 g (3.6 mmol) of cobalt chloride hexahydrate, and then, in portions, 1.1 g (2.9 mmol) of sodium borohydride, are added to a solution of 7.5 g (14 mmol) of the product described in the above Step in 100 ml of methanol. The reaction mixture is stirred for 2 hours at ambient temperature and then filtered. The solvent is evaporated off, and the residue is purified by chromatography on silica gel, using as eluant a cyclohexane/ethyl acetate mixture (80/20), to yield the expected product.
Step c: 3-(7-{[(4-Chlorophenyl)sulphonyl]amino}-4-[2-(methoxycarbonyl)ethyl]-5,6,7,8-tetrahydro-2-naphthyl)propanoic acid
A solution of 6.4 g (12 mmol) of the product described in the above Step in 50 ml of trifluoroacetic acid is stirred for 12 hours at ambient temperature. The solvent is then evaporated off and the residue is taken up in ethyl acetate. The organic phase is washed with brine and then dried and evaporated. The product is obtained after purification by chromatography on silica gel with a dichloromethane/methanol mixture (98/2) as eluant.
Step d: Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-(3-hydroxypropyl)-5,6,7,8-tetrahydro-1-naphthyl)propanoate
9 ml of a 1M solution of BH 3 /THF in THF are slowly added, at ambient temperature, to a solution of 2.8 g (5.2 mmol) of the product described in the above Step in 80 ml of THF. After stirring the mixture for one night at ambient temperature, 10 ml of water are added. The majority of the solvent is evaporated off, and the residue is taken up in ethyl acetate. The organic phase is then washed with brine, dried and evaporated to yield the expected product.
Step e: Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-(3-bromopropyl)-5,6,7,8-tetrahydro-1-naphthyl)propanoate
The product is obtained in accordance with the procedure described in Preparation A, Step c, using as starting material the compound described in the above Step.
PREPARATION C
Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-({4-[2-(tosyloxy)ethyl]phenoxy}methyl)-5,6,7,8-tetrahydro-1-naphthyl)propanoate
Step a: Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-[4-(2-hydroxyethyl)phenoxymethyl]-5,6,7,8-tetrahydro-1-naphthyl)propanoate
165 mg (4.2 mmol) of sodium hydride (60% in mineral oil), and then a solution of 1.05 g (2.1 mmol) of the product described in Preparation A in 50 ml of THF and 1.11 g of crown ether C 18-6 , are added to a solution of 0.58 g (4.2 mmol) of 2-(4-hydroxyphenyl)ethanol in 100 ml of THF. The reaction mixture is heated at reflux for one hour. The majority of the THF is evaporated off, and the mixture is hydrolysed, and adjusted to an acid pH using IN hydrochloric acid. After extraction with dichloromethane, drying and purification by chromatography on silica gel, using as eluant an ethyl acetate/cyclohexane mixture (50/50), the expected product is obtained.
Step b. Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-({4-[2-(tosyloxy)ethyl]phenoxy}methyl)-5,6,7,8-tetrahydro-1-naphthyl)propanoate
1 g (5.4 mmol) of tosyl chloride, and then 0.5 ml of pyridine, are added to a solution of 0.75 g (1.35 mmol) of the product obtained in the above Step in 50 ml of dichloromethane. After stirring at ambient temperature for one night, the mixture is washed with IN hydrochloric acid and dried. After evaporation of the solvent and purification by chromatography on silica gel, using as eluant a cyclohexane/ethyl acetate mixture (60/40), the expected product is obtained.
PREPARATION D
(2,3-Dimethoxy)(4-piperidinyl)methanol
Step a: 1-Benzyl-4-piperidinylcarboxamide
A mixture of 20 g (156 mmol) of isonipecotamide, 32.4 g (234 mmol) of potassium carbonate, 2 g (12 mmol) of potassium iodide and 18.6 ml (156 mmol) of benzyl bromide in 400 ml of acetonitrile is heated at reflux for 5 hours. The solvent is evaporated off and the residue is taken up in a dichloromethane/water mixture. After decanting, extracting with dichloromethane, washing the organic phases with brine and drying, removal of the solvent by evaporation yields the expected product.
Step b: 1-Benzyl-4-piperidylcarbonitrile
26 g (119 mmol) of the product described in the above Step are added in portions to a mixture of 83 ml (890 mmol) of phosphorus oxychloride and 17 g (290 mmol) of sodium chloride. The mixture is heated at reflux for one hour. After cooling, the reaction mixture is poured into 75 ml of concentrated ammonium hydroxide solution. After extraction with dichloromethane, washing the organic phase with water and drying, removal of the solvent by evaporation yields the expected product.
Step c: 1-Benzyl-4-piperidylcarbaldehyde
120 ml of a 1M solution of diisobutylaluminium hydride in hexane are added, at 0° C., to a solution of 22 g (110 mmol) of the product described in the above Step in 500 ml of THF. The mixture is stirred at ambient temperature for 2 hours. After hydrolysis with a 10% hydrochloric acid solution, the mixture is neutralised with a concentrated aqueous sodium hydroxide solution. After extraction with diethyl ether, drying, and removal of the solvent by evaporation, purification by chromatography on silica gel, using as eluant a cyclohexane/ethyl acetate mixture (50/50), yields the expected product.
Step d: (1-Benzyl-4-piperidyl)(2,3-dimethoxyphenyl)methanol
32.5 ml of a 1.6M solution of n-butyllithium in hexane are added at 0° C. to a solution of 7.07 g (51 mmol) of veratrole in 150 ml of THF. After stirring for 2 hours at 0° C., the reaction mixture is cooled to −78° C. and a solution of 8.6 g (42 mmol) of the product described in the above Step in 200 ml of THF is added. Stirring is continued for one hour at −78° C. After returning to ambient temperature, the mixture is hydrolysed with water, extracted with ethyl acetate, dried and concentrated. Purification by chromatography on silica gel, using ethyl acetate as eluant, yields the expected product.
Step e: (2,3-Dimethoxyphenyl)(4-piperidyl)methanol
A mixture of 7.5 g (22 mmol) of the product described in the above Step, 1.5 g of palladium on carbon (10%) and 5.5 g (87 mmol) of ammonium formate in 150 ml of methanol and 30 ml of water is heated at reflux for one hour. After returning to ambient temperature and filtration, the solvent is evaporated off. The residue is taken up in dichloromethane and treated with 2N sodium hydroxide solution until a pH of 10 is reached. After extraction with dichloromethane, drying and removal of the solvent by evaporation, the expected product is obtained.
PREPARATION E
2-(4-Methyl-1-piperazinyl)phenol
Step a: Ethyl 4-(2-hydroxyphenyl)-1-piperazinylcarboxylate
15 ml (156 mmol) of ethyl chloroformate are added to a solution of 18 g (100 mmol) of 2-(1-piperazinyl)phenol in 250 ml of dichloromethane. After stirring at ambient temperature for one hour, the mixture is hydrolysed and then extracted with dichloromethane. The organic phase is washed with a 1N hydrochloric acid solution and dried. Following concentration, the residue obtained is recrystallised from ether to yield the expected product.
Step b: Ethyl 4-[2-(tosyloxy)phenyl]-1-piperazinylcarboxylate
25 g (130 mmol) of para-toluenesulphonyl chloride and 20 ml of triethylamine are added at ambient temperature to a solution of 23 g (91 mmol) of the product described in the above Step in 100 ml of dichloromethane. After stirring for 72 hours at ambient temperature, the solvent is evaporated off. Chromatography on silica gel, using as eluant an ethyl acetate/cyclohexane mixture (30/70), yields the expected product.
Step c: [2-(4-Methyl-1-piperazinyl)phenol] 4-toluenesulphonate
3 g (79 mmol) of lithium aluminium hydride are added at 0° C. to a solution of 23.2 g (57 mmol) of the product described in the above Step in 100 ml of THF. The mixture is stirred for 2 hours at ambient temperature and then hydrolysed. After concentration and extraction with dichloromethane, the organic phase is dried and concentrated to yield the expected compound.
Step d: 2-(4-Methyl-1-piperazinyl)phenol
A mixture of 18 g (52 mmol) of the product described in the above Step and 44 g (785 mmol) of potassium hydroxide in 400 ml of ethanol is heated at reflux for 2 hours. After returning to ambient temperature, the pH is adjusted to 7 using 1N hydrochloric acid. Following concentration, the mixture is extracted with dichloromethane and the organic phase is dried and then concentrated to yield the expected product.
PREPARATION F
4-(4-Methyl-1-piperazinyl)phenol
The product is obtained in accordance with the procedure described in Preparation E, with the replacement of 2-(1-piperazinyl)phenol with 4-(1-piperazinyl)phenol in Step a.
EXAMPLE 1
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{2-[4-(4-fluorobenzoyl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
Stade a: Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-{2-[4-(4-fluorobenzoyl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoate
6.5 g (17.3 mmol) of 4-(4-fluorobenzoyl)piperidine tosylate and 2.4 g (17.3 mmol) of potassium carbonate are added to a solution of 3.5 g (5.7 mmol) of methyl 3-[6-{[(4-chlorophenyl)sulphonyl]amino}-3-(2-{[(4-methylphenyl)sulphonyl]oxy}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoate, described in Application EP 864 561, in 100 ml of DMF. The reaction mixture is heated at reflux for one hour, then concentrated. The residue is taken up in dichloromethane and washed with water. The organic phase is dried and concentrated and then purified by chromatography on silica gel, using as eluant a dichloromethane/methanol/ammonia mixture (98/2/0.2), to yield the expected compound.
Stade b: 3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{2-[4-(4-fluorobenzoyl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
A solution of 2.2 g (3.5 mmol) of the product described in the above Step is heated at reflux for two hours in the presence of 3.5 ml of 2N sodium hydroxide solution. The reaction mixture is filtered and the filtrate is concentrated. 100 ml of water are added and the pH is adjusted to 5 using acetic acid. The precipitate formed is then filtered off and recrystallised from dichloromethane to yield the title compound.
Melting point: 210° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
63.20
5.79
4.47
5.11
Found:
62.89
5.87
4.46
4.82
EXAMPLE 2
3-[6-{[(4-Chlorophenyl)sulphonyl]amino}-3-(2-{4-[(2,3-dimethoxyphenyl)(hydroxy)methyl]-1-piperidinyl}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement in Step a of 4-(4-fluorobenzoyl)piperidine tosylate with the compound described in Preparation D.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
62.63
6.46
4.17
4.78
Found:
62.13
7.00
4.17
4.64
EXAMPLE 3
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{2-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of 4-(4-fluorobenzoyl)piperidine tosylate with 6-fluoro-3-piperidin-4-ylbenzo[d]isoxazole hydrochloride in Step a.
Melting point: 125° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
61.92
5.51
6.56
5.01
Found:
61.33
5.45
6.36
4.91
EXAMPLE 4
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{2-[4-(6-fluoro-1,2-benzisothiazol-3-yl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of 4-(4-fluorobenzoyl)piperidine tosylate with 6-fluoro-3-piperidin-4-ylbenzo[d]isothiazole hydrochloride in Step a.
Melting point: 232° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
60.40
5.38
6.40
9.77
Found:
60.17
5.36
6.39
9.50
EXAMPLE 5
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{2-[4-(1,2-benzisothiazol-3-yl)-1-piperazinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of 4-(4-fluorobenzoyl)piperidine tosylate with 3-piperazin-1-ylbenzo[d]isothiazole hydrochloride in Step a.
EXAMPLE 6
3-(3-(2-{4-[bis(4-Fluorophenyl)methylene]-1-piperidinyl}ethyl)-6-{[(4-chlorophenyl)sulphonyl]amino}-5,6,7,8-tetrahydro-1-naphthyl)-propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of 4-(4-fluorobenzoyl)piperidine tosylate with bis(4-fluorophenyl)methylenepiperidine in Step a.
Melting point: 242° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
66.42
5.57
3.97
4.55
Found:
66.27
5.52
4.05
4.32
EXAMPLE 7
3-[6-{[(4-Chlorophenyl)sulphonyl]amino}-3-(2-{3-[2-(4-fluorophenyl)-2-oxoethyl]-1-pyrrolidinyl}ethyl)-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of 4-(4-fluorobenzoyl)piperidine tosylate with 1-(4-fluorophenyl)-2-pyrrolidin-3-ylethanone hydrochloride in Step a.
Melting point: 143° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
63.20
5.79
4.47
5.11
Found:
63.79
5.79
4.52
4.99
EXAMPLE 8
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-2-{2-[4-(4-fluorobenzoyl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of methyl 3-[6-{[(4-chlorophenyl)sulphonyl]amino}-3-(2-{[(4-methylphenyl)sulphonyl]oxy}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoate with methyl 3-[6-{[(4-chlorophenyl)sulphonyl]amino}-2-(2-{[(4-methylphenyl)sulphonyl]oxy}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoate described in Application EP 864 561.
Melting point: 223° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
63.20
5.79
4.47
5.11
Found:
63.14
5.80
4.56
5.17
EXAMPLE 9
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{[4-(4-fluorobenzoyl)-1-piperidinyl]methyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of methyl 3-[6-{[(4-chlorophenyl)sulphonyl]amino}-3-(2-{[(4-methylphenyl)sulphonyl]oxy}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoate with the product described in Preparation A.
Melting point: 147° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
62.69
5.59
4.59
5.23
Found:
62.99
5.49
4.48
5.17
EXAMPLE 10
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of methyl 3-[6-{[(4-chlorophenyl)sulphonyl]amino}-3-(2-{[(4-methylphenyl)sulphonyl]oxy}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoate with the product described in Preparation B.
Melting point: 118° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
63.69
5.97
4.37
5.00
Found:
63.55
6.02
4.37
4.98
EXAMPLE 11
3-(6-{[(4-Chlorophenyl)sulphony]amino}-3-{3-[4-(4-fluorobenzoyl)-1-piperazinyl]propyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of methyl 3-[6-{[(4-chlorophenyl)sulphonyl]amino}-3-(2-{[(4-methylphenyl)sulphonyl]oxy}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoate with the product described in Preparation B, and of 4-(4-fluorobenzoyl)piperidine tosylate with (4-fluorophenyl)piperazine.
Elemental microanalysis:
C %
H %
N %
Calculated:
59.07
5.89
6.46
Found:
59.10
5.83
6.34
EXAMPLE 12
3-{6-{[(4-Chlorophenyl)sulphonyl]amino}-3-[(4-{2-[4-(4-fluorobenzoyl)-1-piperidinyl]ethyl}phenoxy)methyl]-5,6,7,8-tetrahydro-1-naphthyl}propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of methyl 3-[6-{[(4-chlorophenyl)sulphonyl]amino}-3-(2-{[(4-methylphenyl)sulphonyl]oxy}ethyl)-5,6,7,8-tetrahydro-1-naphthyl]propanoate with the product described in Preparation C.
Melting point: 196° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
62.52
5.77
3.82
4.37
Found:
64.89
6.29
3.84
4.34
EXAMPLE 13
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{[2-(4-methyl-1-piperazinyl)phenoxy]methyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
Stade a: Methyl 3-(6-{[(4-chlorophenyl)sulphonyl]amino}-3-{[2-(4-methyl-1-piperazinyl)phenoxy]methyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoate
A mixture of 1.30 g (2.6 mmol) of the product described in Preparation A, 0.5 g (2.6 mmol) of the product described in Preparation E, 200 mg (5.2 mmol) of sodium hydride (60% in oil) and 670 mg of crown ether C 18-6 is heated at reflux for two hours. After cooling the mixture, 2 ml of acetic acid are added and the reaction mixture is concentrated. The residue is taken up in dichloromethane and washed with water. The organic phase is dried, concentrated and purified by chromatography on silica gel, using as eluant a dichloromethane/methanol/ammonia mixture (95/5/0.5), to yield the expected product.
Stade b: 3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{[2-(4-methyl-1-piperazinyl)phenoxy]methyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Step b of Example 1, using as starting material the compound described in the above Step.
Melting point: 122° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
62.25
6.07
7.02
5.36
Found:
61.52
6.09
6.84
5.22
EXAMPLE 14
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{[4-(4-methyl-1-piperazinyl)phenoxy]methyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 13, with the replacement in Step a of the product described in Preparation E with the product described in Preparation F.
Melting point: 148° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
62.25
6.07
7.02
5.36
Found:
61.94
6.36
6.66
5.11
EXAMPLE 15
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{2-[4-(6-fluoro-1,2-benzo[b]thiophen-3-yl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of 4-(4-fluorobenzoyl)piperidine tosylate with 4-(6-fluorobenzo[b]thiophen-3-yl)piperidine hydrochloride in Step a.
Melting point: 140° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
62.32
5.54
4.28
9.79
Found:
62.01
5.36
4.28
9.80
EXAMPLE 16
3-(6-{[(4-Chlorophenyl)sulphonyl]amino}-3-{2-[4-(6-fluoro-1H-indazol-3-yl)-1-piperidinyl]ethyl}-5,6,7,8-tetrahydro-1-naphthyl)propanoic acid
The expected product is obtained in accordance with the procedure described in Example 1, with the replacement of 4-(4-fluorobenzoyl)piperidine tosylate with 6-fluoro-3-piperidin-4-yl-1H-indazole dihydrochloride in Step a.
Melting point: 142° C.
Elemental microanalysis:
C %
H %
N %
S %
Calculated:
62.01
5.68
8.77
5.02
Found:
61.98
5.74
8.70
4.83
PHARMACOLOGICAL STUDY
EXAMPLE A
Platelet Aggregation in Man
Venous blood is obtained from human volunteers who have not taken aspirin for at least 14 days prior to the experiment. The blood is removed over sodium citrate (0.109 M) (1 vol. of citrate over 9 vol. of blood). Platelet-rich plasma (PRP) is obtained by centrifugation (20° C.) at 200 g for 10 minutes. The number of platelets is on average 250000 PL/mm 3 . The PRP is stored at room temperature until the test and is used within 2 hours of having been taken. The TXA 2 agonist U46619 is used at a concentration of 1 μM and 5-hydroxytryptamine is used at a concentration of 10 μM, the latter in the presence of 0.3 μM adenosine diphosphate and 1 μM adrenalin.
The compounds of the invention inhibit platelet aggregation induced by the TXA 2 agonist as well as that produced by 5-hydroxytryptamine. By way of example, the IC 50 values of the compound of Example 4 are 170 nM and 230 nM respectively for the two targets. The values indicate that the compounds of the invention are powerful platelet anti-aggregants, which act in a balanced manner on the two activation routes, that of TXA 2 and that of serotonin.
EXAMPLE B
Pharmaceutical Composition
Formulation for the preparation of 1000 tablets each comprising
5 mg of active ingredient:
compound of Example 4
5 g
hydroxypropyl methylcellulose
2 g
wheat starch
10 g
lactose
100 g
magnesium stearate
3 g | Compound of formula (I):
which is useful as a TXA 2 and 5-HT 2 receptor antagonist and pharmaceutical compositions containing the same. | 2 |
This application is a divisional application of U.S. Ser. No. 11/109,396, filed Apr. 19, 2005, now U.S. Pat. No. 7,183,408, which is a divisional of U.S. Ser. No. 10/348,727, filed Jan. 21, 2003, now U.S. Pat. No. 6,933,393, which is a divisional application of U.S. Ser. No. 10/198,682, filed Jul. 18, 2002, now U.S. Pat. No. 6,545,153, which is a divisional application of U.S. Ser. No. 10/015,558, filed Dec. 17, 2001, now U.S. Pat. No. 6,476,235 B2, which claims benefit of Provisional Application U.S. Ser. No. 60/260,505, filed Jan. 9, 2001.
FIELD OF THE INVENTION
An improved synthesis for the preparation of 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide is described where methyl cyanoacetate is converted in eight operations or fewer to the desired product, as well as other valuable intermediates used in the process.
BACKGROUND OF THE INVENTION
5-(4-Fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide is a valuable intermediate in the synthesis of Lipitor® (atorvastatin calcium) known by the chemical name [R—(R*,R*)]-2-(4-fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrole-1-heptanoic acid calcium salt (2:1) trihydrate. The aforementioned compound is useful as an inhibitor of the enzyme 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) and is thus useful as a hypolipidemic and/or hypocholesterolemic agent.
U.S. Pat. No. 4,681,893, which is herein incorporated by reference, discloses certain trans-6-[2-(3- or 4-carboxamido-substituted-pyrrol-1-yl)alkyl]-4-hydroxy-pyran-2-ones including trans (±)-5-(4-fluorophenyl)-2-(1-methylethyl)-N, 4-diphenyl-1-](2-tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide.
U.S. Pat. No. 5,273,995, which is herein incorporated by reference, discloses the enantiomer having the (R,R) form of the ring-opened acid of trans-5-(4-fluorophenyl)-2-(1-methylethyl)-N, 4-diphenyl-1-[(2-tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide, i.e., [R—(R*,R*)]-2-(4-fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrole-1-heptanoic acid.
U.S. Pat. Nos. 5,003,080; 5,097,045; 5,103,024; 5,124,482; 5,149,837; 5,155,251; 5,216,174; 5,245,047; 5,248,793; 5,280,126; 5,397,792; 5,342,952; 5,298,627; 5,446,054; 5,470,981; 5,489,690; 5,489,691; 5,510,488; 5,998,633; and 6,087,511, which are herein incorporated by reference, disclose various processes and key intermediates for preparing atorvastatin.
Crystalline forms of atorvastatin calcium are disclosed in U.S. Pat. Nos. 5,969,156 and 6,121,461 which are herein incorporated by reference.
A synthetic procedure for the preparation of 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide is disclosed in U.S. Pat. No. 5,273,995.
The asymmetric reduction of β-ketoesters, as well as β-diketones, is a well-established transformation in organic synthesis. However, the complexity of these reactions increases in the case of 1,3,5-tricarbonyl systems and poor yields and poor stereoselectivities often result. In fact, investigations by Saburi ( Tetrahedron , 1997, 1993; 49) and Carpentier ( Eur. J. Org. Chem . 1999; 3421) have independently demonstrated low to moderate diastereo- and/or enantio-selectivities for diketoester asymmetric hydrogenations. Furthermore, the fact that the processes in the prior art require high pressure hydrogenation and extended reaction times makes these procedures impractical and not amenable to large-scale manufacturing processes.
However, we have surprisingly and unexpectedly found that the diol esters of the present invention, (R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid esters, can be obtained directly from the corresponding 1,3,5-tricarbonyl precursors in a highly stereoselective manner via a mild and efficient ruthenium-catalyzed asymmetric hydrogenation reaction utilizing chiral non-racemic diphosphine ligands in the presence of secondary activating agents such as protic acids.
The object of the present invention is a short and efficient process for the preparation of 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide. The present process avoids the use of a costly chiral raw material ((R)-4-cyano-3-hydroxy-butyric acid ethyl ester), and a low temperature diastereoselective borane reduction. Furthermore, a key Paal-Knorr condensation step, common to the present and prior art processes, has been improved through a significant decrease in reaction time.
Thus, the present process has significant advantages over the prior art processes and is amenable to large-scale synthesis.
SUMMARY OF THE INVENTION
Accordingly, the first aspect of the present invention is an improved process for the preparation of a compound of Formula (13)
which comprises:
Step (a) reacting a compound of Formula (1)
wherein R is alkyl, aryl, arylalkyl, or heteroaryl in a solvent with a compound of Formula (2)
R 1 —H (2)
wherein R 1 is —XR wherein
X is O, S, or Se, or R 1 is
wherein R 2 or R 3 is independently
alkyl, cycloalkyl, arylalkyl, or aryl, or R 2 and R 3 together are —(CH 2 ) 4 —, —(CH 2 ) 5 —, —(CH(R 4 )—CH 2 ) 3 —, —(CH(R 4 )—CH 2 ) 4 —, —(CH(R 4 )—(CH 2 ) 2 —CH(R 4 ))—, —(CH(R 4 )—CH 2 ) 3 —CH(R 4 ))—, —CH 2 —CH 2 -A-CH 2 —CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 —CH(R 4 )— wherein R 4 is alkyl of from one to four carbon atoms, A is O, S, or N and R is as defined above to afford a compound of Formula (3)
wherein R 1 is as defined above;
Step (b) reacting a compound of Formula (3) with hydrogen in the presence of a catalyst and a strong acid in a solvent to afford a compound of Formula (4)
wherein Y is Cl, Br, TsO, MsO, or HSO 4 , and R 1 is as defined above;
Step (c) reacting a compound of Formula (4) with a base in a solvent followed by the addition of a compound of Formula (5)
R—CO 2 H (5)
wherein R is as defined above in a solvent to afford a compound of Formula (6)
wherein R and R 1 are as defined above;
Step (d) reacting a compound of Formula (6) with Compound (7)
in a solvent with removal of water to afford a compound of Formula (8)
wherein R 1 is as defined above;
Step (e) reacting a compound of Formula (8) with a compound of Formula (9)
wherein M is sodium, lithium, potassium, zinc, magnesium, copper, calcium, or aluminum and R 1 is as defined above, in a solvent in the presence of a strong base to afford a compound of Formula (10)
wherein R 1 is as defined above;
Step (f) reacting a compound of Formula (10) with hydrogen in the presence of a catalyst in a solvent in the presence of an acid to afford a compound of Formula (11)
wherein R 1 is as defined above or a compound of Formula (11a)
Step (g) reacting a compound of Formula (11 b)
wherein R 1a is OH, —XR wherein
X is O, S, or Se, or R 1a is
wherein R 2 or R 3 is independently
alkyl, cycloalkyl, arylalkyl, or aryl, or R 2 and R 3 together are —(CH 2 ) 4 —, —(CH 2 ) 5 —, —(CH(R 4 )—CH 2 ) 3 —, —(CH(R 4 )—CH 2 ) 4 —, —(CH(R 4 )—(CH 2 ) 2 —CH(R 4 ))—, —(CH(R 4 )—(CH 2 ) 3 —CH(R 4 ))—, —CH 2 —CH 2 -A-CH 2 —CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 —CH(R 4 )— wherein R 4 is alkyl of from one to four carbon atoms, A is O, S, or N, and R is as defined above in a solvent in the presence of an acid, followed by reaction with a base, an acylating agent, and an acylation catalyst in a solvent to afford a compound of Formula (12)
Step (h) reacting a compound of Formula (12) with HO-M in an alcohol of Formula (17) or (17b)
HOCH 2 -Aryl (17) or HO-Allyl (17b)
wherein M is sodium, lithium, potassium, zinc, magnesium, copper, calcium, or aluminum; or with a compound of Formula (16) or (16b)
M ⊕⊖ OCH 2 -Aryl (16) or M ⊕⊖ O-Allyl (16b)
wherein M is as defined above in an alcohol of Formula (17) or (17b) wherein aryl or allyl in a compound of Formula (16) or (16b) and (17) or (17b) is the same, in a solvent followed by the addition of hydrogen in the presence of a catalyst and an acid to afford the compound of Formula (13).
A second aspect of the present invention is an improved process for the preparation of a compound of Formula (8).
wherein R 1 is as defined above which comprises:
reacting a compound of Formula (4)
wherein Y is Cl, Br, TsO, MsO, or HSO 4 , and R 1 is as defined above with a compound of Formula (20)
R—CO 2 ⊖⊕ M (20)
wherein R and M are as defined above with Compound (7)
in a solvent with removal of water to afford a compound of Formula (8).
A third aspect of the present invention is an improved process for the preparation of compound (13)
which comprises:
Step (a) reacting a compound of Formula (11) with an acetal of Formula (15)
wherein R 5 and R 5a are independently the same or different and are, methyl, ethyl, or —(CH 2 ) n — wherein n is an integer of 2 to 4, and R is as defined above in a solvent in the presence of an acid followed by the addition of an aldehyde corresponding to the previous acetal in the presence of a base to afford a compound of Formula (14)
wherein R 1 and R are as defined above;
Step (b) reacting a compound of Formula (14) in a nucleophilic solvent in the presence of an acid or optionally reaction with hydrogen in the presence of a catalyst and an acid in a solvent to afford the compound of Formula (13); and
Step (c) alternatively, reacting a compound of Formula (11) or (11a) in a non-nucleophilic solvent in the presence of an acid to afford a compound of Formula (13).
A fourth aspect of the present invention is a process for the preparation of a compound of Formula (11 b)
wherein R 1a is OH, —XR wherein
X is O, S, or Se, or R 1a is
wherein R 2 or R 3 is independently
R 3 alkyl, cycloalkyl, arylalkyl, or aryl, or R 2 and R 3 together are —(CH 2 ) 4 —, —(CH 2 ) 5 —, —(CH(R 4 )—CH 2 ) 3 —, —(CH(R 4 )—CH 2 ) 4 —, —(CH(R 4 )—(CH 2 ) 2 —CH(R 4 ))—, —(CH(R 4 )—(CH 2 ) 3 —CH(R 4 ))—, —CH 2 —CH 2 -A-CH 2 —CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 —CH(R 4 )—
wherein R 4 is alkyl of from one to four carbon atoms, A is O, S, or N, and R is alkyl, aryl, arylalkyl, or heteroaryl which comprises:
Step (a) reacting a compound of Formula (10)
wherein R 1 is as defined above with one mole of hydrogen in the presence of a catalyst in a solvent in the presence of an acid to afford compounds of Formula (18) and/or Formula (18a)
wherein R 1 is as defined above; and
Step (b) reacting either a compound of Formula (18) or (18a) with hydrogen in the presence of a catalyst in a solvent in the presence of an acid to afford a compound of Formula (11b).
A fifth aspect of the present invention is a compound of Formula (6)
wherein R is alkyl, aryl, arylalkyl, or heteroaryl, and
R 1 is XR wherein
X is O, S, or Se, or R 1 is
wherein R 2 or R 3 is independently
alkyl, cycloalkyl, arylalkyl, or aryl or R 2 and R 3 together are —(CH 2 ) 4 —, —(CH 2 ) 5 —, —(CH(R 4 )—CH 2 ) 3 —, —(CH(R 4 )—CH 2 ) 4 —, —(CH(R 4 )—(CH 2 ) 2 —CH(R 4 ))—, —(CH(R 4 )—(CH 2 ) 3 —CH(R 4 ))—, —CH 2 —CH 2 -A-CH 2 —CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 —CH(R 4 )—
wherein R 4 is alkyl of from one to four carbon atoms, A is O, S, or N and R is as defined above.
Particularly preferred, is a compound of Formula (6) wherein R is PhCH 2 — or (CH 3 ) 3 —C—, and R 1 is
More particularly preferred, is a compound of Formula (6) wherein R is PhCH 2 — and R 1 is
A sixth aspect of the present invention is a compound of Formula (8)
wherein R 1 is as defined above.
Particularly preferred is a compound of Formula (8) wherein R 1 is
A seventh aspect of the present invention is a compound of Formula (10) or a pharmaceutically acceptable salt thereof
wherein R 1 is as defined above.
Particularly preferred is a compound of Formula (10) wherein R 1 is —O-tertiary butyl, —O-isopropyl, —O-ethyl, —O-methyl,
or —NMe 2 .
An eighth aspect of the present invention is the compound of Formula (12)
A ninth aspect of the present invention is a compound of Formula (18) or a pharmaceutically acceptable salt thereof
wherein R 1 is as defined above.
Particularly preferred is a compound of Formula (18) wherein R 1 is —O-tertiary butyl, —O-isopropyl, —O-ethyl, —O-methyl,
or —NMe 2 .
A tenth aspect of the present invention is a compound of Formula (18a) or a pharmaceutically acceptable salt thereof
wherein R 1 is as defined above.
Particularly preferred is a compound of Formula (18a) wherein R 1 is —O-tertiary butyl, —O-isopropyl, —O-ethyl, —O-methyl,
or —NMe 2 .
DETAILED DESCRIPTION OF THE INVENTION
The term “alkyl” means a straight or branched hydrocarbon radical having from 1 to 8 carbon atoms and includes, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like.
“Alkoxy” and “thioalkoxy” are O-alkyl or S-alkyl of from 1 to 6 carbon atoms as defined above for “alkyl”.
The term “cycloalkyl” means a saturated hydrocarbon ring having 3 to 8 carbon atoms and includes, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and the like.
The term “aryl” means an aromatic radical which is a phenyl group, a phenylalkyl group, a phenyl group substituted by 1 to 4 substituents selected from alkyl as defined above, alkoxy as defined above, thioalkoxy as defined above, halogen, trifluoromethyl, dialkylamino as defined above for alkyl, nitro, cyano,
as defined above for alkyl, —(CH 2 ) n 2-N(alkyl) 2 wherein n 2 is an integer of 1 to 5 and alkyl is defined above and
as defined above for alkyl and n 2 .
The term “allyl” means a hydrocarbon radical of 3 to 8 carbon atoms, containing a double bond between carbons 2 and 3, unsubstituted or substituted by 1 to 3 substituents on the carbons containing the double bond selected from alkyl or aryl as defined above, and includes, for example, propenyl, 2-butenyl, cinnamyl, and the like.
The term “arylalkyl” means an aromatic radical attached to an alkyl radical wherein aryl and alkyl are as defined above for example, benzyl, phenylethyl, 3-phenylpropyl, (4-chlorophenyl)methyl, and the like.
“Alkali metal” is a metal in Group IA of the periodic table and includes, for example, lithium, sodium, potassium, and the like.
“Alkaline-earth metal” is a metal in Group IIA of the periodic table and includes, for example, calcium, barium, strontium, magnesium, and the like.
The term “heteroaryl” means a 5- and 6-membered heteroaromatic radical which may optionally be fused to a benzene ring containing 1 to 3 heteroatoms selected from N, O, and S and includes, for example, a heteroaromatic radical which is 2- or 3-thienyl, 2- or 3-furanyl, 2- or 3-pyrrolyl, 2-, 3-, or 4-pyridinyl, 2-pyrazinyl, 2-, 4-, or 5-pyrimidinyl, 3- or 4-pyridazinyl, 1H-indol-6-yl, 1H-indol-5-yl, 1H-benzimidazol-6-yl, 1H-benzimidazol-5-yl, 2-, 4-, or 5-thiazolyl, 3-, 4-, or 5-isothiazolyl, 2-, 4-, or 5-imidazolyl, 3-, 4-, or 5-pyrazolyl, or 2- or 5-thiadiazolyl and the like optionally substituted by a substituent selected from alkyl as defined above, alkoxy as defined above, thioalkoxy as defined above, halogen, trifluoromethyl, dialkylamino as defined above for alkyl, nitro, cyano,
as defined above for alkyl, —(CH 2 ) n 2-N(alkyl) 2 wherein n 2 is an integer of 1 to 5, and alkyl is as defined above, and
as defined above for alkyl and n 2 .
Pharmaceutically acceptable acid addition salts of the compounds of the present invention include salts derived from inorganic acids such as hydrochloric, nitric, phosphoric, sulfuric, hydrobromic, hydriodic, hydrofluoric, phosphorous, and the like, as well as the salts derived from nontoxic organic acids, such as aliphatic mono- and dicarboxylic acids, phenyl-substituted alkanoic acids, hydroxy alkanoic acids, alkanedioic acids, aromatic acids, aliphatic and aromatic sulfonic acids, etc. Such salts thus include sulfate, pyrosulfate, bisulfate, sulfite, bisulfite, nitrate, phosphate, monohydrogenphosphate, dihydrogenphosphate, metaphosphate, pyrophosphate, chloride, bromide, iodide, acetate, trifluoroacetate, propionate, caprylate, isobutyrate, oxalate, malonate, succinate, suberate, sebacate, fumarate, maleate, mandelate, benzoate, chlorobenzoate, methylbenzoate, dinitrobenzoate, phthalate, benzenesulfonate, toluenesulfonate, phenylacetate, citrate, lactate, maleate, tartrate, methanesulfonate, and the like. Also contemplated are salts of amino acids such as arginate and the like and gluconate, galacturonate (see, for example, Berge S. M. et al., “Pharmaceutical Salts,” J. of Pharma. Sci ., 1977; 66:1).
The acid addition salts of said basic compounds are prepared by contacting the free base form with a sufficient amount of the desired acid to produce the salt in the conventional manner. The free base form may be regenerated by contacting the salt form with a base and isolating the free base in the conventional manner. The free base forms differ from their respective salt forms somewhat in certain physical properties such as solubility in polar solvents, but otherwise the salts are equivalent to their respective free base for purposes of the present invention.
Pharmaceutically acceptable base addition salts are formed with metals or amines, such as alkali and alkaline earth metals or organic amines. Examples of metals used as cations are sodium, potassium, magnesium, calcium, and the like. Examples of suitable amines are N,N′-dibenzylethylenediamine, chloroprocaine, choline, diethanolamine, dicyclohexylamine, ethylenediamine, N-methylglucamine, and procaine (see, for example, Berge S. M. et al., “Pharmaceutical Salts,” J. of Pharma Sci ., 1977; 66:1).
The base addition salts of said acidic compounds are prepared by contacting the free acid form with a sufficient amount of the desired base to produce the salt in the conventional manner. The free acid form may be regenerated by contacting the salt form with an acid and isolating the free acid in the conventional manner. The free acid forms differ from their respective salt forms somewhat in certain physical properties such as solubility in polar solvents, but otherwise the salts are equivalent to their respective free acid for purposes of the present invention.
Additionally, the compounds of the present invention can exist in unsolvated forms as well as solvated forms, including hydrated forms. In general, the solvated forms, including hydrated forms, are equivalent to unsolvated forms and are intended to be encompassed within the scope of the present invention.
The following list contains abbreviations and acronyms used within the schemes and text:
H 2 SO 4 Sulfuric acid NaOMe Sodium methoxide MeOH Methanol MtBE Methyl tert-butyl ether GC Gas chromatography Pt/C Platinum on carbon Pd/C Palladium on carbon H 2 Hydrogen HCl Hydrochloric acid Hg Mercury psi Pounds per square inch iPrOH (IPA) Isopropyl alcohol HPLC High pressure liquid chromatography NaOH Sodium hydroxide CH 2 Cl 2 Dichloromethane (methylene chloride) DMSO-d 6 Deuterated dimethylsulfoxide THF Tetrahydrofuran Na 2 SO 4 Sodium sulfate nBuLi n-Butyllithium NaCl Sodium chloride KOtBu Potassium tert-butoxide NaHCO 3 Sodium bicarbonate BnOH Benzyl alcohol Pd(OH) 2 /C Palladium hydroxide on carbon H 2 O Water PivOH Pivalic acid PhCHO Benzaldehyde PhCH 3 Toluene CDCl 3 Deuterated chloroform BnONa Sodium benzylate NH 4 OH Ammonium hydroxide PhCH(OMe) 2 Benzaldehyde dimethyl acetal MsOH Methanesulfonic acid pTsOH para Toluenesulfonic acid CSA Camphorsulfonic acid Ph Phenyl NaH Sodium hydride KH Potassium hydride EtOAc Ethyl acetate tBuOH(HOtBu) tert-Butanol PhCH 2 CO 2 H Phenylacetic acid NaNH 2 Sodium amide KHMDS Potassium hexamethyldisilazide LAH Lithium aluminum hydride Pd/Al 2 O 3 Palladium on alumina APCI Atmospheric pressure chemical ionization ESI Electrospray ionization DCI Direct chemical ionization 1 H NMR Proton nuclear magnetic resonance spectroscopy 13 C NMR 13 Carbon nuclear magnetic resonance spectroscopy BINAP (R)-(+)-2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl pTol-BINAP (R)-(+)-Bis(di-p-tolyl-phosphino)-1,1′-binaphthyl Cl-MeO-BIPHEP [(R)-(+)-5,5′-Dichloro-6,6′-dimethoxy[1,1′-biphenyl]-2,2′-diyl]-bis-diphenylphosphine C2-TunaPhos [(12aR)-6,7-dihydrodibenzo[e,g] [1,4]dioxocin-1,12-diyl]-bis-diphenylphosphine C4-TunaPhos [(14aR)-6,7,8,9-tetrahydrodibenzo[b,d][1,6]dioxecin-1,14-diyl]-bis-diphenylphosphine MeO-BIPHEP [(1S)-(−)-6,6′-Dimethoxy[1,1′-biphenyl]-2,2′-diyl]-bis-diphenylphosphine p-cymene 4-isopropyltoluene ee Enantiomeric excess HRMS High resolution mass spectrometry m/z Mass to charge ratio t R Retention time
The process of the present invention in its first aspect is a new, improved, economical, and commercially feasible method for the preparation of the compound of Formula (13)
The process of the present invention in its first aspect is outlined in Scheme 1. Thus, a compound of Formula (I) wherein R is alkyl, aryl, arylalkyl, or heteroaryl is reacted with a compound of Formula (2) wherein R 1 is —XR wherein
X is O, S, Se or R 1 is
wherein R 2 or R 3 is independently
alkyl, cycloalkyl, arylalkyl, or aryl, or R 2 and R 3 together are —(CH 2 ) 4 —, —(CH 2 ) 5 —, —(CH(R 4 )—CH 2 ) 3 —, —(CH(R 4 )CH 2 ) 4 —, —(CH(R 4 )—(CH 2 ) 2 —CH(R 4 ))—, —(CH(R 4 )—(CH 2 ) 3 —CH(R 4 ))—, —CH 2 —CH 2 -A-CH 2 —CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 —CH(R 4 )— wherein R 4 is alkyl of from one to four carbon atoms, A is O, S, or N and R is as defined above in a solvent such as, for example, methyl tertiary butyl ether, and the like, to afford a compound of Formula (3) whereas R 1 is as defined above. Preferably, the reaction is carried out with a compound of Formula (2) wherein R 1 —H is morpholine in methyl tertiary butyl ether.
A compound of Formula (3) is reacted with hydrogen in the presence of a catalyst such as, for example, Pt/C, Pd/C in the presence of an acid such as, for example, a strong acid, for example, hydrochloric acid, hydrobromic acid, p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid, and the like (optionally the reduction is carried out with Sponge Ni/NH 4 OH, metal hydrides, and the like, to afford the free base of a compound of Formula (4)) in a solvent such as, for example, methanol, ethanol, and the like to afford a compound of Formula (4) wherein Y is Cl, Br, TsO, MsO, or HSO 4 and R 1 is as defined above.
Preferably, the reaction is carried out in the presence of Pt/C, hydrochloric acid and hydrogen in methanol.
A compound of Formula (4) is reacted with a base such as, for example, sodium methoxide and the like in a solvent such as, for example, tetrahydrofuran, toluene, methyl tertiary butyl ether, and the like, and in an alcohol such as, for example, isopropanol, ethanol, methanol, and the like, to afford the free base followed by reaction with a compound of Formula (5) wherein R is as defined above in a solvent such as, for example, isopropanol, tetrahydrofuran, and the like to afford a compound of Formula (6) wherein R is as defined above. Optionally, the free base of a compound of Formula (4) may be reacted with a compound of Formula (5) to afford a compound of Formula (6). Preferably, the reaction is carried out with sodium methoxide in methyl tertiary butyl ether and methanol to afford the free base followed by reaction with phenylacetic in tetrahydrofuran.
A compound of Formula (6) is reacted with the compound of Formula (7) in a solvent such as, for example, a protic, an aprotic, a polar or a non-polar solvent, for example, tetrahydrofuran and the like with removal of water with the aid of a chemical drying agent such as, for example, molecular sieves and the like or with the aid of a Dean-Stark water trap or using azeotropic distillation with a suitable solvent such as, for example toluene and the like to afford a compound of Formula (8) wherein R 1 is as defined above. Preferably, the reaction is carried out with activated 3A molecular sieves in tetrahydrofuran.
A compound of Formula (8) is reacted with a compound of Formula (9) wherein M is sodium, lithium, potassium, zinc, magnesium, copper, calcium, or aluminum and R 1 is as defined above in a solvent such as, for example, a nonreactive aprotic solvent, for example, tetrahydrofuran, toluene, and the like in the presence of a strong base such as, for example, n-butyllithium, lithium or potassium hexamethyldisilazide, lithium diisopropylamide, and the like to afford a compound of Formula (10) wherein R 1 is as defined above. Preferably, the reaction is carried out with a compound of Formula (9) wherein M is sodium, the base is n-butyllithium and the solvent is tetrahydrofuran.
The carbonyls of a compound of Formula (10) in Scheme 1 are shown in the keto form. However, a compound of Formula (10) can undergo “keto-enol” tautomerism and thus can exist in several tautomeric forms which are encompassed within the present invention.
A compound of Formula (10) is treated with hydrogen in the presence of a catalyst such as, for example, a chiral non-racemic ruthenium (II)-diphosphine complex. For example, a ruthenium catalyst precursor such as [dichloro-(1,5-cyclooctadiene)] ruthenium (II) oligomer and chiral diphosphine ligand such as [(R)-(+)-2,2′-bis(diphenyl-phosphino)-1,1′-binaphthyl]. However, any chiral non-racemic ruthenium (II)/diphosphine combination may be employed in this reduction reaction. For example, ruthenium (II) catalyst precursors include [dibromo-(1,5-cyclooctadiene)]ruthenium (II) dimer, [bis-(2-methallyl)cycloocta-1,5-diene]ruthenium (II) complex and [dichloro (p-cymene)]ruthenium (II) dimer, and the like. Examples of effective chiral diphosphine ligands include 2,2′-bis(di-p-tolyl-phosphino)-1,1′-binaphthyl, 2-diphenyl-phosphinomethyl-4-diphenylphosphino-1-tert-butoxy-carbonylpyrrolidine, tricyclo[8.2.2.24,7]hexadeca-4,6,10,12,13,15-hexaene-5,11-diyl-bis(diphenylphosphine) derivatives, 4,4′-bidibenzofuran-3,3′-diylbis(diphenylphosphine), 6,6′-dimethoxy[1,1′-biphenyl]-2,2′-diyl]bis-diphenylphosphine, [5,5′-dichloro-6,6′-dimethoxy[1,1′-biphenyl]-2,2′-diyl]-bis-diphenylphosphine, and 1,2-bis(2,5-dimethylphospholano) derivatives and the like in a solvent such as, for example, methanol, ethanol, isopropanol, and the like, optionally in the presence of a co-solvent, for example, dichloromethane, tetrahydrofuran, toluene and the like in the presence of an acid such as, for example, hydrochloric acid, hydrobromic acid, Dowex® ion exchange resin, and the like to afford a compound of Formula (11) or a compound of Formula (11a) wherein R 1 is as defined above. Preferably, the reaction is carried out with dichloro(p-cymene) ruthenium (II) dimer and [(R)-(+)-5,5′-dichloro-6,6′-dimethoxy[1,1′-biphenyl]-2,2′-diyl]-bis-diphenylphosphine in methanol in the presence of hydrobromic acid.
A compound of Formula (11b) wherein R 1a is wherein R 1a is OH, —XR wherein
X is O, S, or Se, or R 1a is
wherein R 2 or R 3 is independently
alkyl, cycloalkyl, arylalkyl, or aryl, or R 2 and R 3 together are —(CH 2 ) 4 —, —(CH 2 ) 5 —, —(CH(R 4 )—CH 2 ) 3 —, —(CH(R 4 )—CH 2 ) 4 —, —(CH(R 4 )(CH 2 ) 2 —CH(R 4 ))—, —(CH(R 4 )—(CH 2 ) 3 —CH(R 4 ))—, —CH 2 —CH 2 -A-CH 2 —CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 CH 2 —, —CH(R 4 )—CH 2 -A-CH 2 —CH(R 4 )—
wherein R 4 is alkyl of from one to four carbon atoms, A is O, S, or N, and R is alkyl, aryl, arylalkyl, or heteroaryl is reacted with an acid such as, for example, p-toluenesulfonic acid, camphor-sulfonic acid, sulfuric acid, hydrogen chloride, and the like in a non-nucleophilic solvent such as, for example, toluene, acetonitrile, dichloromethane, methyl tertiary butyl ether, and the like, followed by reaction with a base, such as, for example, triethylamine, pyridine, diisopropylethylamine, and the like, and with an acylating agent, such as, for example, acetic anhydride, benzoyl chloride, benzyl chloroformate, and the like, in the presence of 4-dimethylaminopyridine to afford the compound of Formula (12). Preferably, the reaction is carried out in toluene in the presence of p-toluenesulfonic acid, followed by treatment with triethylamine, acetic anhydride, and 4-dimethylaminopyridine in toluene.
A compound of Formula (12) is reacted with HO-M in an alcohol of Formula (17) or (17b) wherein M is sodium, lithium, potassium, zinc, magnesium, copper, calcium, or aluminum, or with a compound of Formula (16) or (16b) wherein M is as defined above in an alcohol of Formula (17) or (17b) wherein aryl or allyl in a compound of Formula (16) or (16b) and (17) or (17b) is the same, in an optional cosolvent, such as, for example, a nonnucleophilic solvent, for example, acetone, tetrahydrofuran, 1,2-dimethoxyethane, and the like, followed by the addition of hydrogen in the presence of a catalyst, such as, for example, Pd(OH) 2 /C, Pd/C, Pd/Al 2 O 3 , and the like, in the presence of an acid, such as, for example, hydrochloric acid, hydrobromic acid, sulfuric acid, and the like, to afford the compound of Formula (13). Preferably, the reaction is carried out with sodium hydroxide in benzyl alcohol followed by hydrogenation in the presence of Pd(OH) 2 /C and sulfuric acid.
The process of the present invention in its second aspect is outlined in Scheme 2. Thus, a compound of Formula (4), prepared as described in Scheme 1, is reacted with a compound of Formula (20) wherein R and M are as defined above and a compound of Formula (7) with removal of water with the aid of a chemical drying agent such as, for example, molecular sieves and the like or with the aid of a Dean-Stark water trap or using azeotropic distillation with a suitable solvent such as, for example tetrahydrofuran, toluene, and the like, to afford a compound of Formula (8) wherein R 1 is as defined above. Preferably, the reaction is carried out with a compound of Formula (20) wherein R is PhCH 2 and M is sodium in the presence of activated 3A molecular seives in tetrahydrofuran.
The process of the present invention in its third aspect is outlined in Scheme 3. Thus, a compound of Formula (11) is reacted with an acetal of Formula (15) wherein R 5 and R 5a are independently the same or different and are, methyl, ethyl, or —(CH 2 ) n — wherein n is an integer of 2 to 4, and R is as defined above in the presence of an acid such as, for example, hydrochloric acid, pyridinium p-toluenesulfonate, p-toluenesulfonic acid and the like in a solvent such as, for example, toluene, dichloromethane, methyl tertiary butyl ether, and the like, followed by the addition of an aldehyde corresponding to the previous acetal of Formula (15) in the presence of a strong base such as, for example, a non-nucleophilic base, for example, potassium tertiary butoxide, potassium bis(trimethylsilyl)amide, 1,8-diazabicyclo[5.4.0] undec-7-ene and the like, to afford a compound of Formula (14) wherein R 1 and R are as defined above. Preferably, the reaction is carried out with benzaldehyde dimethyl acetal in toluene in the presence of p-toluenesulfonic acid followed by the addition of benzaldehyde and potassium tertiary butoxide in tetrahydrofuran.
A compound of Formula (14) is reacted with hydrogen in the presence of a catalyst such as, for example, palladium on carbon or platinum on carbon and the like in the presence of an acid such as, for example, hydrochloric acid and the like in a solvent such as, for example, toluene, tetrahydrofuran, methyl tertiary butyl ether, ethyl acetate, and the like, and an alcohol, such as, for example, methanol, ethanol, and the like, to afford a compound of Formula (13). Preferably, the reaction is carried out in toluene in the presence of platinum on carbon in the presence of methanol in the presence of hydrochloric acid.
Optionally, a compound of Formula (14) is reacted with an acid such as, for example, hydrochloric acid, pyridinium p-toluenesulfonate, p-toluenesulfonic acid, and the like, in a solvent such as, for example, toluene, dichloromethane, methyl tertiary butyl ether, and the like to afford the compound of Formula (13). Preferably, the reaction is carried out in methylene chloride in the presence of p-toluenesulfonic acid.
Alternatively, a compound of Formula (11) is reacted with an acid, such as, for example, hydrochloric acid, hydrobromic acid, p-toluenesulfonic acid, and the like, in a non-nucleophilic solvent, such as, for example, toluene, acetonitrile, methyl tertiary butyl ether, tetrahydrofuran, and the like, to afford a compound of Formula (13). Preferably, the reaction is carried out in toluene in the presence of p-toluenesulfonic acid.
The process of the present invention in its fourth aspect is outlined in Scheme 4. Thus, a compound of Formula (10) wherein R 1 is as defined above is reacted with one molar equivalent of hydrogen in the presence of a catalyst using the methodology described above for the conversion of a compound of Formula (10) to a compound of Formula (11) to afford either a compound of Formula (18) or Formula (18a) wherein R 1 is as defined above or a mixture thereof. A mixture of compounds of Formula (18) and (18a) may be separated using conventional methodology, such as, for example, chromatography and the like. Preferably, a mixture of compounds of Formula (18) and (18a) is separated using HPLC.
A compound of Formula (18) or (18a) or a mixture thereof is reacted with hydrogen in the presence of a catalyst as described above for preparing a compound of Formula (11) to afford a compound of Formula (11b) wherein R 1a is as defined above. Preferably, the reaction is carried out using at least one molar equivalent of hydrogen.
The compound of Formula (13) can be converted to atorvastatin calcium (19) using the procedures disclosed in U.S. Pat. No. 5,273,995 and 5,969,156.
The following nonlimiting examples illustrate the inventors' preferred methods for preparing the compounds of the invention.
EXAMPLE 1
5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide
Step 1: 3-Morpholin-4-yl-3-oxo-propionitrile
A nitrogen inerted reactor equipped with reflux condenser, nitrogen inlet and mechanical stirring is charged with morpholine (1.2 mol), methyl cyanoacetate (1.0 mol) and MtBE (52 mL). The homogeneous solution is heated to ca. 55° C. and stirred at that temperature for 12 to 18 hours. MtBE (33 mL) is added over ca. 15 minutes, and the solution is slowly cooled below 50° C. where nucleation becomes evident. Additional MtBE (66 mL) is added over a 1-hour period. During this time, the reaction is allowed to cool to near ambient temperature. After complete MtBE addition, the reaction is cooled with stirring to ca. 0° C. The resulting precipitate is collected via filtration and the cake is washed with additional MtBE (ca. 40 mL). The solid is dried under vacuum at ca. 45° C. to provide 3-morpholin-4-yl-3-oxo-propionitrile (139 g). This material is used in subsequent steps without further purification.
m/z (APCI(m+1)) 154.9; calcd for C 7 H 10 N 2 O 2 154.07.
Step 2: 3-Amino-1-morpholin-4-yl-propan-1-one; hydrochloride
A nitrogen inerted reactor is charged with 5% Pt—C (43 g; 58% water-wet) followed by 3-morpholin-4-yl-3-oxo-propionitrile (2.8 mol). A solution of MeOH (3.4 L) and 12N HCl (3.08 mol) is added at such a rate as to maintain an internal temperature of ca. 25° C. The vessel and its contents are degassed via three N 2 pressure purges (50 psi). The atmosphere is switched to hydrogen via three H 2 pressure purges (50 psi), and the reaction is stirred vigorously at ca. 25° C. under a sustained pressure of hydrogen (50 psi) for ca. 24 hours. The H 2 pressure is released and replaced with N 2 . The reaction is passed through filter agent, which is subsequently washed with MeOH (500 mL). The reaction is concentrated in vacuo to a volume of ca. 1.4 L, and IPA (2.2 L) is added. The reaction mixture is cooled to 0° C. and filtered. The filter cake is washed with MtBE (500 mL) and dried under vacuum at ca. 30° C. to provide 3-amino-1-morpholin-4-yl-propan-1-one, hydrochloride as a white solid (439 g). This material is used in subsequent steps without further purification.
1 H NMR (400 MHz, DMSO) δ 2.72 (t, 2H, J=6.78), 2.96 (t, 2H, J=6.77), 3.83-3.44 (m, 2H), 3.52-3.58 (m, 2H), 8.08 (bs, 3H).
13 C NMR (100 MHz, DMSO) δ 168.4, 65.9, 45.1, 41.45, 35.1, 29.6.
Free base: m/z (APCI(m+1)) 159.2; calcd for C 7 H 14 N 2 O 2 158.11.
Step 3: 3-Amino-1-morpholin-4-yl-propan-1-one; compound with phenylacetic acid
A reactor is charged with 3-amino-1-morpholin-4-yl-propan-1-one; hydrochloride (765 mmol). MeOH (380 mL) is added, and the mixture is stirred vigorously at room temperature for ca. 10 minutes. MtBE (380 mL) is added and the resulting slurry is cooled to −10° C., where a 25% (w/w) MeOH solution of NaOMe (765 mmol) is added slowly via addition funnel at such a rate as to maintain an internal temperature of ca. −10° C. The resulting suspension is stirred vigorously under a N 2 atmosphere as it is allowed to warm to 0° C. Solids are removed via filtration, rinsing with additional MtBE (50 mL). Solvent is removed in vacuo to provide the free base as a crude oil that is taken up in MtBE (600 mL). The mixture is cooled with vigorous agitation to ca. 0° C., where phenylacetic acid (765 mmol) is added slowly as a solution in MtBE (300 mL). The reaction mixture is stirred an additional 10 minutes after complete addition, during which time the product precipitates out of solution. The solids are collected via filtration, washed with additional MtBE (100 mL) and dried under vacuum at ≦40° C. to provide 3-amino-1-morpholin-4-yl-propan-1-one; compound with phenylacetic acid (191 g). This material is carried on to subsequent steps without further purification, or optionally, it can be re-precipitated from MtBE.
1 H NMR (400 MHz, DMSO) δ 2.55 (t, 2H, J=6.78), 2.86 (t, 2H, J=6.78) 3.62 (t, 2H), 3.42 (t, 2H), 6.22 (bs, 3H), 7.25−7.12 (m, 5H).
13 C NMR (100 MHz, DMSO) δ 174.2, 169.0, 138.2, 129.2, 127.8, 125.5, 66.0, 45.2, 44.4, 41.4, 35.7, 31.6.
Step 4: 5-(4-Fluorophenyl)-2-isopropyl-1-(3-morpholin-4-yl-3-oxo-propyl)-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide
Method A
A nitrogen inerted reactor, equipped with a suitable reflux condenser and soxhlet extractor containing freshly activated 3A molecular sieves (4-8 mesh; 97.2 g), is charged with 3-amino-1-morpholin-4-yl-propan-1-one, compound with phenylacetic acid (765 mmol) and 2-[2-(4-fluorophenyl)-2-oxo-1-phenyl-ethyl]-4-methyl-3-oxo-pentanoic acid phenylamide (450 mmol). THF (360 mL) is added, and the resulting solution is stirred vigorously as the reaction is heated at reflux temperature for ca. 24 hours, during which time the product begins to precipitate. Half-saturated aqueous NaHCO 3 (100 mL) is added, and the reaction mixture is cooled with continued stirring to ca. 0° C. MtBE (100 mL) is added, and the solids are collected via filtration. The solid is washed with distilled water (100 mL) and MtBE (2×100 mL), collected, and dried under vacuum at ≦50° C. to afford 5-(4-fluorophenyl)-2-isopropyl-1-(3-morpholin-4-yl-3-oxo-propyl)-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide as a white solid (194 g). This material is carried on to subsequent steps without further purification.
m/z (APCI(m −1 )) 538.2; (APCI(m+1) 540.2; calcd for C 33 H 34 FN 3 O 3 539.26.
Method B
A nitrogen inerted reactor, equipped with a suitable reflux condenser and soxhlet extractor containing freshly activated 3A molecular sieves (4-8 mesh; 36 g), is charged with 3-amino-1-morpholin-4-yl-propan-1-one hydrochloride (170 mmol), phenylacetic acid sodium salt (170 mmol) and 2-[2-(4-fluorophenyl)-2-oxo-1-phenyl-ethyl]-4-methyl-3-oxo-pentanoic acid phenylamide (100 mmol). THF (150 mL) is added, and the resulting solution is stirred vigorously as the reaction is heated at reflux temperature for ca. 24 hours, during which time the product begins to precipitate. Aqueous NaHCO 3 (100 mL) is added slowly, and the reaction mixture is cooled with continued stirring to ca. 0° C. MtBE (100 mL) is added, and the solids are collected via filtration. The yellow-colored solid is washed with distilled water (15 mL) and MtBE (2×15 mL), collected, and dried under vacuum at ≦50° C. to afford 5-(4-fluorophenyl)-2-isopropyl-1-(3-morpholin-4-yl-3-oxo-propyl)-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide as a white solid (42.1 g). This material is carried on to subsequent steps without further purification.
m/z (APCI(m −1 )) 538.2; (APCI(m+1) 540.2; calcd for C 33 H 34 FN 3 O 3 539.26.
Method C
A nitrogen inerted reactor equipped with reflux condenser, nitrogen inlet and mechanical stirring is charged with morpholine (1.2 mol), methyl cyanoacetate (1.0 mol), and MtBE (52 mL). The homogeneous solution is heated to ca. 55° C. and stirred at that temperature for 12 to 18 hours. MtBE (33 mL) is added over ca. 15 minutes, and the solution is slowly cooled below 50° C. until nucleation becomes evident. Additional MtBE (66 mL) is added over a 1-hour period. During this time, the reaction is allowed to cool to near ambient temperature. After complete MtBE addition, the reaction is cooled with stirring to ca. 0° C. The resulting precipitate is collected via filtration and the cake is washed with additional MtBE (40 mL). The crude 3-morpholin-4-yl-3-oxo-propionitrile is taken up in MeOH (2 L) and transferred to a nitrogen inerted pressure reactor that has been charged with 5% Pt—C (55 g; 58% water-wet). HCl (12 N, 1.1 mol) is added at such a rate as to maintain an internal temperature of ca. 25° C. The vessel and its contents are degassed via three N 2 pressure purges (50 psi). The atmosphere is switched to hydrogen via three H 2 pressure purges (50 psi), and the reaction is stirred vigorously at ca. 25° C. under a sustained pressure of hydrogen (50 psi) for ca. 24 hours. The H 2 pressure is released and replaced with N 2 . The reaction is passed through filter agent, which is subsequently washed with MeOH (500 mL). The reaction is concentrated to a MeOH-wet solid, which is reslurried in IPA (100 mL). The slurry is cooled to 0° C. and filtered. The filter cake is washed with cold (0° C.) IPA (75 mL) and reslurried in MeOH (500 mL) and MtBE (500 mL). The slurry is cooled with agitation to −10° C. where a 25% (w/w) solution of NaOMe in MeOH (1 mol) is added dropwise at such a rate as to maintain an internal reaction temperature of ≦−5° C. The resulting suspension is filtered to afford a clear solution of free base. The solvent is removed in vacuo to provide a crude oil that is taken up in THF (450 mL) and cooled to ca. 0° C. This solution is transferred into a nitrogen inerted reactor that contains phenylacetic acid (1.0 mol) and 2-[2-(4-fluorophenyl)-2-oxo-1-phenyl-ethyl]-4-methyl-3-oxo-pentanoic acid phenylamide (590 mmol). The reactor is equipped with a suitable reflux condenser and soxhlet extractor containing freshly activated 3A molecular sieves (4-8 mesh; 125 g). The resulting solution is stirred vigorously as the reaction is refluxed under a N 2 atmosphere for ca. 24 hours, during which time the product begins to precipitate. Half-saturated aqueous NaHCO 3 (130 mL) is added slowly, and the reaction mixture is cooled with continued stirring to ca. 0° C. MtBE (130 mL) is added, and the solids are collected via filtration. The solid is washed with distilled water (130 mL) and MtBE (2×130 mL), collected, and dried under vacuum at ≦50° C. to afford 5-(4-fluorophenyl)-2-isopropyl-1-(3-morpholin-4-yl-3-oxo-propyl)-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide as a white solid (223 g). This material is carried on to subsequent steps without further purification.
m/z (APCI(m-1)) 538.2; (APCI(m+1) 540.2; calcd for C 33 H 34 FN 3 O 3 539.26.
Step 5: 7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, ethyl ester
Method A
A dry, nitrogen inerted reactor is charged with sodium hydride (300 mmol). Anhydrous THF (150 mL) is added and the resulting mixture is cooled under nitrogen to ca. −20° C. Ethyl acetoacetate (307 mmol) is added at such a rate as to maintain an internal reaction temperature of ≦−10° C. The addition is followed by a THF rinse (30 mL) and the resulting solution is stirred for approximately 45 minutes at ≦−10° C. The temperature is allowed to cool to ca. −18° C. A 10.0 M solution of n-BuLi in hexanes (300 mmol) is added at such a rate as to maintain an internal reaction temperature of ≦−4° C. The addition is followed by a THF rinse (30 mL) and the resulting orange solution is stirred for about 90 minutes at ≦−4° C. The temperature is allowed to cool to ca. −25° C. To the solution of dienolate is added 5-(4-fluorophenyl)-2-isopropyl-1-(3-morpholin-4-yl-3-oxo-propyl)-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide (74 mmol), and the resulting slurry is stirred at ca. −23° C. for 20 hours. The reaction is quenched into a mixture of 18% aqueous HCl (898 mmol) and MtBE (20 mL) at such a rate as to maintain an internal reaction temperature of ≦−2° C. The reactor and transfer system is rinsed with THF (30 mL) and transferred to the reaction mixture. The two-phase solution is allowed to warm to ca. 20° C. with stirring. The mixture is transferred to a separatory funnel, and the phases are allowed to separate. The organic layer is washed with water (33 mL) and saturated aqueous NaCl (33 mL). All aqueous layers are back-extracted with MtBE (40 mL). The two organic layers are combined and concentrated in vacuo to a crude oil maintaining an internal batch temperature of ≦60° C. EtOH (24 mL) is added to the oil and, again, the mixture is concentrated in vacuo. EtOH (330 mL) and water (33 mL) are immediately added to the resulting oil, and the solution of product is allowed to stand at ≦10° C. for ca. 14 hours. The resulting solid is collected, washed with cold 20% aqueous EtOH (100 mL) and dried in vacuo to afford 7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, ethyl ester (35.6 g) as a white solid. This material is carried on to subsequent steps without further purification, or optionally, it can be re-precipitated from IPA/H 2 O.
HRMS m/z (ESI(m-1)) 581.2463; calcd for C 35 H 35 FN 2 O 5 582.2530.
In a process analogous to Step 5 METHOD A, by substituting the appropriate ester or amide of acetoacetic acid for ethyl acetoacetate, one obtains the following compounds:
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, tert-butyl ester.
HRMS m/z (ESI(m −1 )) 609.2772; APCI(m+1) 611.3; calcd for C 37 H 39 FN 2 O 5 610.2843.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, isopropyl ester.
m/z (DCI(m+1)) 597; calcd for C 36 H 37 FN 2 O 5 596.27.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, methyl ester.
m/z (DCI(m+1)) 569; calcd for C 34 H 33 FN 2 O 5 568.24.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, morpholino amide.
HRMS m/z (ESI(m −1 )) 622.2715; calcd for C 37 H 38 FN 3 O 5 623.2795.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, N,N-dimethyl amide.
m/z (DCI(m+1)) 582; calcd for C 35 H 36 FN 3 O 4 581.27.
Method B
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, tert-butyl ester
A nitrogen inerted reactor is charged with the sodium salt of tert-butyl acetoacetate (100 mmol). Anhydrous toluene (71.5 mL) and THF (8.2 mL, 101 mmol) are added, and the resulting solution is cooled under a positive pressure of nitrogen to ca. −10° C. A 10 M hexanes solution of n-BuLi (104 mmol) is added at such a rate as to maintain an internal reaction temperature of ≦1° C. The resulting solution is stirred an additional 20 to 30 minutes after complete addition as the temperature is allowed to cool to ca. −6° C. Meanwhile, 5-(4-fluorophenyl)-2-isopropyl-1-(3-morpholin-4-yl-3-oxo-propyl)-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide (25 mmol) is charged to a second nitrogen inerted reactor. Anhydrous THF (50 mL) is added at room temperature, and the resulting slurry is cooled to ca. −10° C. and stirred for 15 to 90 minutes. The solution of dienolate is added to the slurry of morpholine amide at such a rate as to maintain an internal reaction temperature ca. −5° C. Following this addition, the slurry is stirred at ca. −5° C. for ≧2 hours. Water (35 mL) is added with vigorous agitation at such a rate as to maintain an internal reaction temperature of ≦0° C. Concentrated 37% hydrochloric acid (19.0 mL, 229 mmol) is added at such a rate as to maintain an internal reaction temperature of ≦0° C. The two-layered reaction mixture is vacuum distilled, removing >50% of the organic solvents. The distillation is stopped and the lower aqueous layer is discarded. Water (55 mL) is added and the vacuum distillation is continued until a majority of the organic solvents are removed. [Note: It is preferable to drain and replace the aqueous layer before initiating the vacuum distillation.] IPA (100 mL) is added followed by water (100 mL). The mixture is stirred for ≧6 hours, allowing for solidification of the product. The solid is collected via filtration, and the cake is washed with pre-mixed 1:1 IPA:H 2 O. The resulting solid is dried in vacuo at 35° C. to provide 7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, tert-butyl ester (14.1 g) as a white solid. This material is carried on to subsequent steps without further purification, or optionally, it can be re-precipitated from toluene.
HRMS m/z (ESI(m −1 )) 609.2772; APCI(m+1) 611.3; calcd for C 37 H 39 FN 2 O 5 610.2843.
In a process analogous to Step 5 METHOD B, by substituting the sodium salt of the appropriate ester or amide of acetoacetic acid for the sodium salt of tert-butyl acetoacetate, one obtains the following compounds:
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, ethyl ester.
HRMS m/z (ESI(m-1)) 581.2463; calcd for C 35 H 35 FN 2 O 5 582.2530.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, isopropyl ester.
m/z (DCI(m+1)) 597; calcd for C 36 H 37 FN 2 O 5 596.27.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, methyl ester.
m/z (DCI(m+1)) 569; calcd for C 34 H 33 FN 2 O 5 568.24.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, morpholino amide.
HRMS m/z (ESI(m −1 )) 622.2715; calcd for C 37 H 38 FN 3 O 5 623.2795.
7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, N,N-dimethyl amide.
m/z (DCI(m+1)) 582; calcd for C 35 H 36 FN 3 O 4 581.27.
Step 6: (5R)-7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1yl]-3,5-dihydroxy-heptanoic acid, methyl ester
Method A
A nitrogen inerted pressure reactor is charged with 7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, ethyl ester (100.0 mmol) and MeOH (250 mL). The resulting slurry is heated with stirring to ca. 55° C. to afford a homogeneous solution. The vessel and its contents are degassed via three 50 psi pressure purges with argon. Under a steady flow of argon, 1 M methanolic HBr (7.0 mmol) and the RuCl 2 (DMF) n [(R)—Cl-MeO-BIPHEP)] catalyst (0.5 mmol) are added, and the reactor is given an additional 50 psi pressure purge with argon. The atmosphere is switched to hydrogen via three 50 psi pressure purges. The reaction is stirred vigorously at 65° C. under a sustained pressure of hydrogen (50 psi) until hydrogen uptake ceases. The reaction is allowed to cool to ambient temperature, and the hydrogen pressure is released and replaced with nitrogen. The crude MeOH solution of (5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, methyl ester is carried on to subsequent steps without purification, or optionally, it can be isolated via flash column chromatography on silica gel, eluting with ethyl acetate-heptane mixtures.
HPLC analysis (YMC ODS AQ S5; 1 mL/min; 30° C.; 254 nm: CH 3 CN/H 2 O, 60:40 (0-22 min) to 100:0 (27-37 min) to 60:40) indicated a syn:anti ratio of 1:1.5. Chiral HPLC analysis (Chiralcel OD-H column; 5% EtOH:Hexanes; t R (3R,5R)=23.1 min./t R (3R,5S)=18.0 min./t R (3S,5S)=24.8 min./t R (3S,5R)=19.9 min.) indicated an enantiomeric excess at C-5 of ≧98%, favoring the (R) configuration.
m/z (DCI(m+1)) 573; calcd for C 34 H 37 FN 2 O 5 572.27.
In a process analogous to Step 6 METHOD A, using the appropriate alcoholic solvent in place of MeOH, one obtains the following compounds, for example:
(5R)-7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, ethyl ester.
m/z (DCI(m+1)) 587; calcd for C 35 H 39 FN 2 O 5 586.28.
Chiral HPLC analysis (Chiralcel OD-H column; 5% EtOH:Hexanes; t R (3R,5R)=17.6 min./t R (3R,5S)=14.7 min./t R (3S,5S)=20.9 min./t R (3S,5R)=15.9 min.) indicated an enantiomeric excess at C-5 of ≧98%, favoring the (R) configuration.
(5R)-7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, isopropyl ester.
m/z (DCI(m+1)) 601; calcd for C 36 H 41 FN 2 O 5 600.30.
In a process analogous to Step 6 METHOD A, using the appropriate ester or amide from Step 5 in a non-nucleophilic/non-coordinating solvent (e.g., toluene) in place of MeOH, and acetic acid in place of HBr, one can avoid transesterification and obtain the following compounds, for example:
(5R)-7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, tert-butyl ester.
m/z (APCI(m+1)) 615.3; calcd for C 37 H 43 FN 2 O 5 614.32.
(5R)-7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, morpholino amide.
m/z (APCI(m −1 +HCO 2 H)) 672.3; calcd for C 37 H 42 FN 3 O 5 627.31.
(5R)-7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, N,N-dimethyl amide.
m/z (APCI(m+1)) 586; calcd for C 35 H 40 FN 3 O 4 585.30.
In a process analogous to Step 6 METHOD A, using alternative Ru(II)-chiral diphosphine complexes in place of RuCl 2 (DMF) n [(R)—Cl-MeO-BIPHEP)] as the hydrogenation catalyst, one can obtain the identical products with varying enantiomeric excess at C-5. For example, in the reduction of 7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, ethyl ester to (5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, methyl ester proceeded as follows:
RuCl 2 (DMF) n [(R)-(+)-BINAP] complex provided product with 90% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
RuCl 2 (DMF) n [(R)-(+)-pTol-BINAP] complex provided product with 91% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
RuCl 2 (DMF) n [(R)-(+)-C4-TunaPhos] complex provided product with 93% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
RuCl 2 (DMF) n [(R)-(+)-C2-TunaPhos] complex provided product with 98% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
RuCl 2 (DMF) n [(S)-(−)-MeO-BIPHEP] complex provided product with 95% ee (favoring the (S) configuration) at C-5 as determined by chiral HPLC analysis.
RuCl 2 [(R)-(+)-Cl-MeO-BIPHEP] (NEt 3 ) n complex provided product with ≧98% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
RuCl 2 [(R)-(+)-BINAP] (NEt 3 ) n complex provided product with 91% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
RuCl 2 [(R)-(+)-pTol-BINAP] (NEt 3 ) n complex provided product with 91% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
[Ru(TFA) 2 ((R)-(+)-Cl-MeO-BIPHEP) n complex provided product with ≧98% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
[Ru(TFA) 2 ((R)-(+)-BINAP)] n complex provided product with 90% ee (favoring the (R) configuration) at C-5 as determined by chiral HPLC analysis.
Method B
A nitrogen inerted pressure reactor is charged with benzene ruthenium (II) chloride dimer (11 mg) and (R)-(+)-C2-TunaPhos (26 mg). The reactor is given a pressure purge with N 2 and N 2 -sparged MeOH (1.0 mL) is added via syringe. The resulting mixture is thoroughly purged with N 2 and stirred at 25° C. for 30 minutes. A solution of 7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, tert-butyl ester (0.5 g) in N 2 -sparged MeOH (4.5 mL) is added to the reactor via syringe, and the resulting mixture is allowed to stir under N 2 at 60° C. for 30 minutes. The solution is stirred at 60° C. under a sustained H 2 pressure of 60 psi for 22 hours. The reaction is cooled to ambient temperature where it is repeatedly purged with N 2 . The crude MeOH solution of (5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, methyl ester is carried on to subsequent steps without purification, or optionally, it can be isolated via flash column chromatography on silica gel, eluting with ethyl acetate-heptane mixtures. HPLC analysis (YMC ODS AQ S5; 1 mL/min; 30° C.; 254 nm: CH 3 CN/H 2 O, 60:40 (0-22 min.) to 100:0 (27-37 min.) to 60:40) indicated a syn:anti ratio of 1:1.4.
Chiral HPLC analysis (Chiralcel OD-H column; 5% EtOH:Hexanes; t R (3R,5R)=23.1 min./t R (3R,5S)=18.0 min./t R (3S,5S)=24.8 min./t R (3S,5R)=19.9 min.) indicated an enantiomeric excess at C-5 of ≧97%, favoring the (R) configuration.
m/z (DCI(m+1)) 573; calcd for C 34 H 37 FN 2 O 5 572.27.
Step 7: 5-(4-Fluorophenyl)-2-isopropyl-1-[2-((S)-6-oxo-3,6-dihydro-2H-pyran-2-yl)-ethyl]-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide
A suitable nitrogen inerted reactor is charged with KOH (110.0 mmol) and water (300 mL). To this rapidly stirring solution is added the crude Step 6 solution of (5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, methyl ester (ca. 100 mmol/>98% ee) in MeOH (250 mL). The mixture is heated under a nitrogen atmosphere to an internal temperature of ca. 85° C. During this time, MeOH is removed via distillation. The resulting reaction mixture is allowed to cool to 45° C., where it is washed with MtBE (2×150 mL). The MtBE phases are separated and discarded. To the 45° C. aqueous phase is added toluene (125 mL), followed by a slow addition of 6N HCl (20 mL). The two-phase mixture is stirred for 10 minutes, and the layers are separated. The aqueous phase is extracted with a second portion of toluene (125 mL) and discarded. The combined organics are heated to reflux under a nitrogen atmosphere. During this time, 130 mL of distillate is collected and discarded. The resulting solution is cooled to ca. 60° C., where NEt 3 (140 mmol), DMAP (2.0 mmol) and Ac 2 O (70.0 mmol) are added successively at such a rate as to maintain an internal reaction temperature of 55° C. to 65° C. This solution is stirred for ca. 1.5 hrs at 60° C. The mixture is cooled to 50° C., where 1N HCl (100 mL) is added slowly. The two-phase mixture is stirred for 10 minutes, the phases are separated, and the aqueous phase discarded. The organic phase is washed with second portions of 1N HCl (100 mL) and water (100 mL) while maintaining a temperature of 45° C. to 55° C. The toluene solution is diluted with Bu 2 O (200 mL) and the resulting solution is slowly cooled to 0° C. with continuous agitation. The resulting solid is collected on a filter funnel and dried under vacuum to provide 5-(4-fluorophenyl)-2-isopropyl-1-[2-((S)-6-oxo-3,6-dihydro-2H-pyran-2-yl)-ethyl]-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide as a white to off-white solid (34.4 g). This material is carried on to subsequent steps without further purification, or optionally, it can be re-precipitated from IPA/H 2 O.
m/z (DCI(m+1)) 523; calcd for C 33 H 31 FN 2 O 3 522.23.
Chiral HPLC analysis (Chiralpak AD column; 1 mL/min; 30° C.; 254 nm; 10% IPA:Hexanes; t R (R)=18 min./t R (S)=16 min.) indicated an enantiomeric excess of >98%, favoring the (R) configuration.
Step 8: 5-(4-Fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide
Method A
An argon-purged reactor is charged with 5-(4-fluorophenyl)-2-isopropyl-1-[2-((S)-6-oxo-3,6-dihydro-2H-pyran-2-yl)-ethyl]-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide (0.020 mol/>99% ee) and benzyl alcohol (52 mL). The reaction mixture is cooled to −10° C. and NaOH (0.040 mol) is added. After stirring for 19 hours at −10° C. the reaction is quenched with 37% HCl (0.042 mol) and diluted with water (25 mL) and toluene (25 mL). After the mixture is warmed to ambient temperature, the lower aqueous layer is discarded. The upper organic layer is combined with 20% Pd(OH) 2 /C (1.0 g) and H 2 SO 4 (0.01 moles) and hydrogenated under 50 psi hydrogen at 50° C. for 16 hours. The reaction mixture is heated to 80° C. and filtered through diatomaceous earth. The reactor and catalyst cake is rinsed with hot toluene (10 mL). The lower aqueous layer is discarded. The upper organic layer is washed with a warm solution of aqueous HCl (0.16 g 37% HCl in 25 mL hot water) and heated to reflux for 2.5 hours under argon, removing water azeotropically. The reaction mixture is cooled to 65° C. and seeded with 5-(4-fluorophenyl)-1′-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide. After 2 hours the reaction mixture is allowed to slowly cool to ambient temperature. The resulting slurry is cooled to about 0° C. The product is collected and washed with cold toluene (25 mL). The resulting solid is dissolved in hot toluene (95 mL) and cooled to 65° C. and held for 2 hours. The reaction mixture is slowly cooled to ambient temperature and further cooled to 0° C. The product is collected, washed with cold toluene (25 mL) and dried in vacuo at 70° C. overnight to afford 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide (8.4 g) as a white solid.
HPLC analysis (YMC ODS AQ S5; 1 mL/min; 30° C.; 254 nm: CH 3 CN/H 2 O, 60:40 (0-22 min.) to 100:0 (27-37 min.) to 60:40) indicated an anti:syn ratio of >99:1.
Chiral HPLC analysis (Chiralcel OF; 1 mL/min; 60° C.; 254 nm; 20% IPA:Hexanes; t R (3R,5R)=26 min./t R (3R,5S)=59 min./t R (3S,5S)=33 min./t R (3S,5R)=37 min.) indicated an enantiomeric excess at C-5 of >99%, favoring the (R) configuration.
m/z (DCI(m+1)) 541; calcd for C 33 H 33 FN 2 O 4 540.24.
In a process analogous to Step 8 METHOD A, substituted benzylic alcohol derivatives (e.g., p-methoxy-benzyl alcohol) may be used in place of benzyl alcohol to afford the corresponding compounds.
Method B
An argon-purged reactor is charged with 5-(4-fluorophenyl)-2-isopropyl-1-[2-((S)-6-oxo-3,6-dihydro-2H-pyran-2-yl)-ethyl]-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide (19.1 mmol/>99% ee) and allyl alcohol (50 mL). The reaction mixture is cooled to −5° C. and LiOH (38.2 mmol) is added. After stirring for 1 hour at −5° C. the reaction is quenched with 37% HCl (42 mmol) and toluene (125 mL). After the mixture is warmed to ambient temperature, the reaction is concentrated to a volume of ca. 75 mL. Additional toluene (50 mL) is added and the reaction is concentrated via distillation to a crude oil that solidifies upon standing. The crude residue is taken up in DME (340 mL). To this solution is added deionized water (20 mL), p-toluenesulfonic acid (2.25 g) and 5% Pd/C (11 g; 50% water-wet). The resulting mixture is heated to 45° C. under a N 2 atmosphere for 1.5 hours and at ambient temperature for an additional 16 hours. The solution is passed through filter aid to remove catalyst, and solvent is removed in vacuo. The residue is taken up in toluene (50 mL). Water (75 mL) and KOH (950 mg) are added, and the reaction mixture is heated to 65° C. where the layers are separated. The aqueous phase is washed with toluene (25 mL) at 65° C. and the combined toluene layers are discarded. To the aqueous phase is added toluene (50 mL), followed by 6N HCl (3.8 mL). The mixture is stirred vigorously at 65° C. for 5 minutes and the phases are separated. The toluene phase is heated to reflux for 2.5 hours under argon, removing water azeotropically. The reaction mixture is cooled to 65° C. and seeded with 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide. After 2 hours the reaction mixture is allowed to slowly cool to ambient temperature. The resulting slurry is cooled to about 0° C. The product is collected and washed with cold toluene (25 mL). The resulting solid is dissolved in hot toluene (95 mL) and cooled to 65° C. and held for 2 hours. The reaction mixture is slowly cooled to ambient temperature and further cooled to 0° C. The product is collected, washed with cold toluene (25 mL) and dried in vacuo at 70° C. overnight to afford 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide as a white solid.
HPLC analysis (YMC ODS AQ S5; 1 mL/min; 30° C.; 254 nm: CH 3 CN/H 2 O, 60:40 (0-22 min) to 100:0 (27-37 min) to 60:40) indicated an anti:syn ratio of >99:1.
Chiral HPLC analysis (ChiralCel OF; 1 mL/min; 60° C.; 254 nm; 20% IPA:Hexanes; t R (3R,5R)=26 min./t R (3R,5S)=59 min. t R (3S,5S)=33 min./t R (3S,5R)=37 min.) indicated an enantiomeric excess at C-5 of >99%, favoring the (R) configuration.
m/z (DCI(m+1)) 541; calcd for C 33 H 33 FN 2 O 4 540.24.
In a process analogous to Step 8 METHOD B, allylic alcohol derivatives (e.g., crotyl alcohol) may be used in place of allyl alcohol to afford the corresponding compounds.
Method C
Operation A
A nitrogen inerted reactor is charged with (5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, tert-butyl ester (10.0 mmol), benzaldehyde dimethyl acetal (44.0 mmol), toluene (40 mL) and p-toluenesulfonic acid monohydrate (1.0 mmol). The reaction is stirred vigorously under vacuum for ca. 20 hours, or until complete reaction as determined by analysis of an aliquot by HPLC. The solution is cooled under a nitrogen atmosphere to ca. −5° C. where a 1M THF solution of KOtBu (9.0 mmol) is added in three equal portions, separated by 30 to 45 minutes. The resulting solution is allowed to stir an additional 12 to 14 hours at 0° C. The reaction is quenched by the slow addition of 1N HCl (10 mL). The resulting two-phase mixture is allowed to warm to ca. 15° C. and is transferred to a separatory funnel where the aqueous phase is removed and discarded. The organic phase is washed with saturated aqueous NaCl (100 mL), dried over anhydrous MgSO 4 (25 g), filtered and concentrated in vacuo to a crude oil. This material is carried on to subsequent steps without purification, or optionally, it can be re-precipitated from ether/hexanes.
m/z (APCI(m+1)) 703.4; calcd for C 44 H 47 FN 2 O 5 702.35.
In a process analogous to Step 8 METHOD C OPERATION A using the appropriate ester from Step 6 in place of (5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, tert-butyl ester, one obtains the following compounds, for example:
((4R,6R)-6-{2-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-ethyl}-2-phenyl-[1,3]dioxan-4-yl)-acetic acid methyl ester.
((4R,6R)-6-{2-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-ethyl}-2-phenyl-[1,3]dioxan-4-yl)-acetic acid ethyl ester.
((4R,6R)-6-{2-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-ethyl}-2-phenyl-[1,3]dioxan-4-yl)-acetic acid isopropyl ester.
Operation B
A nitrogen inerted pressure reactor is charged with ((4R,6R)-6-{2-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-ethyl}-2-phenyl-[1,3]dioxan-4-yl)-acetic acid tert-butyl ester from OPERATION A (5.0 g), 5% Pd/C (0.45 g; 50% H 2 O-wet), 2N HCl in MeOH (1.9 mL), toluene (11 mL), and MeOH (3.1 mL). The vessel and its contents are degassed via two cycles of partial evacuation and nitrogen pressurization (25 mm Hg and 50 psi, respectively). The atmosphere is switched to hydrogen via three cycles of partial evacuation and hydrogen pressurization (25 mm Hg and 50 psi, respectively). The reaction is stirred vigorously at 40° C. under a positive pressure of H 2 (ca. 50 psi) for ca. 2.5 hours. The reaction is allowed to cool to ambient temperature, and the hydrogen pressure is released and replaced with nitrogen. The reaction is passed through filtering agent to remove the catalyst, rinsing thoroughly with MeOH (2×5 mL). To this solution is added KOH (0.6 g) in water (25 mL). The reaction is stirred vigorously under a nitrogen atmosphere and heated to an internal reaction temperature of ca. 90° C., removing MeOH via distillation. The two-phase mixture is allowed to cool to 70° C. and the upper toluene phase is separated and discarded. The aqueous phase is washed with a second portion of toluene (10 mL) at 70° C. This organic wash is also separated and discarded. To the aqueous phase is added toluene (10 mL), followed by a slow addition of 2N HCl (5 mL). The two-phase mixture is stirred for 10 minutes and the layers are separated. The aqueous phase is extracted with a second portion of toluene (10 mL) and is discarded. The combined organics are heated to reflux under a Dean-Stark water trap for 2.5 hours under argon. The reaction mixture is cooled to 65° C. and seeded with 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide. After 2 hours the reaction mixture is allowed to slowly cool to ambient temperature. The resulting slurry is cooled to ca. 0° C. The product is collected and washed with cold toluene (5 mL). The resulting solid is dissolved in hot toluene (20 mL) and cooled to 65° C. and held for 2 hours. The reaction mixture is slowly cooled to ambient temperature and then to 0° C. The product is collected, washed with cold toluene (5 mL) and dried in vacuo at 70° C. overnight to afford 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide as a white solid.
m/z (DCI(m+1)) 541; calcd for C 33 H 33 FN 2 O 4 540.24.
Method D
A nitrogen inerted pressure reactor is charged with 7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dioxo-heptanoic acid, ethyl ester (100.0 mmol) and EtOH (250 mL). The resulting slurry is heated with stirring to ca. 55° C. to afford a homogeneous solution. The vessel and its contents are degassed via three 50 psi pressure purges with argon. Under a steady flow of argon, 1 M ethanolic HBr (7.0 mmol) and the RuCl 2 ([(R)-BINAP] NEt 3 catalyst (0.5 mmol) are added, and the reactor is given an additional 50 psi pressure purge with argon. The atmosphere is switched to hydrogen via three 50 psi pressure purges. The reaction is stirred vigorously at 65° C. under a sustained pressure of hydrogen (50 psi) until H 2 uptake ceases. The reaction is allowed to cool to ca. 50° C., where the hydrogen pressure is released and replaced with nitrogen. The crude EtOH solution of (5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, methyl ester is diluted with toluene (250 mL). To this solution is added benzaldehyde (150 mmol) and p-TsOH monohydrate (5 mmol). The resulting reaction mixture is heated to a pot temperature of 110° C., removing EtOH and water via their toluene azeotropes. The solution is cooled under a nitrogen atmosphere to ca. −5° C. where a 1 M THF solution of KOtBu (90 mmol) is added in three equal portions, separated by 30 to 45 minutes. The resulting solution is allowed to stir an additional 12 to 14 hours at 0° C. The reaction is quenched by the slow addition of 1N HCl (100 mL). The resulting two-phase mixture is allowed to warm to ca. 15° C. and is transferred to a separatory funnel where the aqueous phase is removed and discarded. The organic phase is washed with saturated aqueous NaCl (25 mL), dried over anhydrous MgSO 4 (5 g), filtered and concentrated in vacuo to a crude oil that is taken up in MeOH (200 mL). This solution is transferred to a nitrogen inerted pressure reactor containing 5% Pd/C (5 g; 50% water-wet). Concentrated HCl (2 mL) is added and the reaction is stirred under a sustained pressure of H 2 (50 psi) for ca. 3 hours at 50° C. The reaction mixture is cooled to ambient temperature, the H 2 is replaced by N 2 , and the catalyst is removed via filtration. This solution of (3R,5R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, methyl ester is transferred to a nitrogen inerted reactor charged with KOH (110.0 mmol) and water (300 mL). The mixture is heated under a nitrogen atmosphere to an internal temperature of ca 85° C. During this time, MeOH is removed via distillation. The resulting reaction mixture is allowed to cool to 45° C., where it is washed with MtBE (2×150 mL). The MtBE phases are separated and discarded. To the 45° C. aqueous phase is added toluene (125 mL), followed by a slow addition of 6N HCl (20 mL). The two-phase mixture is stirred for 10 minutes and the layers are separated. The aqueous phase is extracted with a second portion of toluene (125 mL) and is discarded. The combined organics are heated to reflux under a Dean-Stark water trap for 2.5 hours under argon. The reaction mixture is cooled to 65° C. and seeded with 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide. After 2 hours the reaction mixture is allowed to slowly cool to ambient temperature. The resulting slurry is cooled to ca. 0° C. The product is collected and washed with cold toluene (100 mL). The resulting solid is dissolved in hot toluene (350 mL) and cooled to 65° C. where it is held for 2 hours. The reaction mixture is slowly cooled to ambient temperature and then to 0° C. The product is collected, washed with cold toluene (100 mL) and dried in vacuo at 70° C. to afford 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide as a white solid.
m/z (DCI(m+1)) 541; calcd for C 33 H 33 FN 2 O 4 540.24.
Step 9: (R,R)-7-[2-(4-Fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, calcium salt.
An argon-purged reactor is charged with 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide (14.8 mmol), MtBE (45 mL) and MeOH (20 mL). A solution of NaOH (15.2 mmol) in water (103 mL) is added and the reaction mixture heated to 52° C. After heating for ca. 1 hour, the reaction mixture is cooled to 34° C. and the layers are allowed to separate. The upper organic layer is discarded. The lower aqueous layer is washed with MtBE (33 mL) at ca 33° C. The lower aqueous layer is diluted with MtBE (2 mL) and heated to 52° C. under argon. A warm solution of Ca(OAc) 2 -H 2 O (7.5 mmol) in water (44 mL) is added over ca. 2 hours. About 5 minutes after the start of the Ca(OAc) 2 addition, the reaction mixture is seeded with a slurry of (R,R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, calcium salt (0.08 mmol) in water (1.2 mL) and methanol (0.4 mL). After the Ca(OAc) 2 addition is complete, the reaction mixture is held for ca. 15 minutes at 52° C. and cooled to 20° C. The product is collected, washed sequentially with a 2:1 solution of aqueous methanol (48 mL) and water (49 mL). After drying in vacuo at 70° C., (R,R)-7-[2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-phenylcarbamoyl-pyrrol-1-yl]-3,5-dihydroxy-heptanoic acid, calcium salt (8.7 g) is obtained as a white solid. The analytical specifications of this material are in agreement with the values reported in the prior art.
Preparation of Catalysts
EXAMPLE A
RuCl 2 (DMF) n [(R)-(+)-Cl-MeO-BIPHEP] complex
A suitable reaction flask is charged with DMF (17.5 mL). The vessel and its contents are degassed via two cycles of partial evacuation and nitrogen pressurization (25 mm Hg and 10 psi, respectively). The excess nitrogen pressure is released, and benzene ruthenium(II) chloride dimer (0.50 mmol) and (R)-(+)-Cl-MeO-BIPHEP (1.10 mmol) are added in rapid succession. The vessel and its contents are again degassed via two cycles of partial evacuation and nitrogen pressurization (25 mm Hg and 10 psi, respectively). The excess nitrogen pressure is released, and the reactor is heated to ca. 100° C. for 10 minutes. The resulting solution is allowed to cool to ≦50° C. where solvent is removed in vacuo, affording RuCl 2 (DMF) n [(R)-(+)-Cl-MeO-BIPHEP] as a rusty-brown solid. The crude complex is used directly in subsequent reactions without purification or unambiguous characterization, or optionally, can be stored under an inert atmosphere for future use.
In a process analogous to EXAMPLE A using the appropriate chiral diphosphine ligand in place of (R)-(+)-Cl-MeO-BIPHEP, the following complexes can be obtained, for example:
RuCl 2 (DMF) n [(R)-(+)-BINAP] n complex.
RuCl 2 (DMF) n [(R)-(+)-pTol-BINAP] n complex.
RuCl 2 (DMF) n [(R)-(+)-C4-TunaPhos] n complex.
RuCl 2 (DMF) n [(R)-(+)-C2-TunaPhos] n complex.
RuCl 2 (DMF) n [(S)-(−)-MeO-BIPHEP] n complex.
EXAMPLE B
RuCl 2 (R)-(+)-BINAP] (NEt 3 ) n complex
A nitrogen inerted pressure reactor is charged with dichloro-(1,5-cyclooctadiene)-ruthenium (II) dimer (0.15 mmol) and (R)-(+)-BINAP (0.32 mmol). Toluene (8.0 mL) is added, followed by triethylamine (4.5 mmol). The vessel and its contents are degassed via two cycles of partial evacuation and nitrogen pressurization (25 mm Hg and 10 psi, respectively). The excess nitrogen pressure is released, and the reactor is sealed and heated to ca. 140° C. where it is maintained for ca. 4 hours. The resulting clear red solution is allowed to cool to ≦40° C. where solvent is removed in vacuo, affording RuCl 2 [(R)-(+)-BINAP] (NEt 3 ) n complex as a rusty-brown solid. The crude complex is used directly in subsequent reactions without purification or unambiguous characterization, or optionally, can be stored under an inert atmosphere for future use.
In a process analogous to EXAMPLE B using the appropriate chiral diphosphine ligand in place of (R)-(+)-BINAP, the following complexes can be obtained, for example:
RuCl 2 [(R)-(+)-Cl-MeO-BIPHEP] (NEt 3 ) n complex.
RuCl 2 [(R)-(+)-BINAP] (NEt 3 ) n complex.
RuCl 2 [(R)-(+)-pTol-BINAP] (NEt 3 ) n complex.
EXAMPLE C
[Ru(TFA) 2 ((R)-(+)-Cl-MeO-BIPHEP)] n complex
A suitable reaction flask is charged with acetone (50 mL). The vessel and its contents are degassed via two cycles of partial evacuation and argon pressurization (25 mm Hg and 10 psi, respectively). The excess argon pressure is released, and (0.50 mmol) and (R)-(+)-Cl-MeO-BIPHEP (0.51 mmol) are added in rapid succession. The vessel and its contents are again degassed via two cycles of partial evacuation and argon pressurization (25 mm Hg and 10 psi, respectively). The excess argon pressure is released, and the reactor is stirred vigorously at ca. 30° C. Trifluoroacetic acid (1.2 mmol) is added via syringe and the reaction mixture is stirred for an additional 1-hour period. Solvent is removed in vacuo, with careful omission of O 2 , to afford [Ru(TFA) 2 ((R)-(+)-Cl-MeO-BIPHEP)] n complex as a solid. The crude complex is used directly in subsequent reactions without purification or unambiguous characterization, or optionally, can be stored under an inert atmosphere for future use.
In a process analogous to EXAMPLE C using the appropriate chiral diphosphine ligand in place of (R)-(+)-Cl-MeO-BIPHEP, the following complexes can be obtained, for example:
[Ru(TFA) 2 ((R)-(+)-MeO-BIPHEP)] n complex.
[Ru(TFA) 2 ((R)-(+)-BINAP)] n complex.
[Ru(TFA) 2 ((R)-(+)-pTol-BINAP)] n complex. | An improved process for the preparation of 5-(4-fluorophenyl)-1-[2-((2R,4R)-4-hydroxy-6-oxo-tetrahydro-pyran-2-yl)-ethyl]-2-isopropyl-4-phenyl-1H-pyrrole-3-carboxylic acid phenylamide by a novel synthesis is described where methyl cyanoacetate is converted in eight operations or fewer to the desired product, as well as other valuable intermediates used in the process. | 2 |
[0001] This application claims the benefit of U.S. provisional patent application No. 61/774,227, filed on Mar. 7, 2013, the entire contents of which are hereby incorporated by reference.
TECHNICAL FIELD
[0002] The technical field of this disclosure relates generally to a programmable polarity module that can be connected to a direct current (“DC”) power supply for a resistance spot welding gun. The programmable polarity module allows the polarity of the welding gun's electrodes to be controlled, as needed, to best accommodate the resistance spot welding process being practiced at the time.
BACKGROUND
[0003] Resistance spot welding is a process used by a number of industries to join together two or more metal workpieces. The automotive industry, for example, often uses resistance spot welding to join together pre-fabricated sheet metal workpieces during the manufacture of a vehicle door, hood, trunk lid, or lift gate, among others. A number of spot welds are typically formed along a peripheral edge of the metal workpieces or some other bonding region to ensure the part is structurally sound. The most common metal workpieces used today in the automotive industry are those made of steel and an aluminum alloy. The desire to incorporate aluminum alloys into a vehicle has made it enviable to spot weld an aluminum alloy workpiece to another aluminum alloy workpiece or, alternatively, to a steel workpiece.
[0004] The resistance spot welding process is performed by an automated robotic or pedestal welding gun that includes two arms. Each of these arms holds a welding electrode typically comprised of a suitable copper alloy. The welding gun arms can be positioned on opposite sides of a workpiece stack-up and clamped to press the two electrodes against their respective metal workpieces at diametrically common spots. A momentary electrical current is then passed through the metal workpieces from one electrode to the other. Resistance to the flow of electrical current through the metal workpieces and their faying interface (i.e., the contacting interface of the metal workpieces) generates heat at the faying interface. This heat forms a molten weld pool which, upon stoppage of the current flow, solidifies into a weld nugget. After the spot weld is formed, the welding arms release their clamping force, and the spot welding process is repeated at another weld site.
[0005] The electric current that is passed between the opposed electrodes and through the metal workpieces is received from a DC power supply carried by the welding gun. The DC power supply may, for example, be a medium-frequency integrated transformer and rectifier package configured to deliver high DC amperage in accordance with a specified weld schedule. This type of DC power supply, and other similar types as well, furnishes the opposed electrodes with fixed opposite polarities when electrically connected to the welding gun; that is, after the DC power supply has been installed, one electrode is always the positive electrode and the other is always the negative electrode.
[0006] The polarity assigned to the welding electrodes is not inconsequential. It has been found, for instance, that a polarity bias exists when spot welding (1) an aluminum alloy workpiece to another aluminum alloy workpiece, and (2) an aluminum alloy workpiece to a steel workpiece. A less pronounced polarity bias also exists when spot welding a steel workpiece to another steel workpiece and in certain practices of projection welding. The ability to control which electrode has the positive/negative polarity while the welding gun and the DC power supply remain electrically connected—including the ability to switch electrode polarities at any time—would permit more operationally effective spot welding practices to be developed in at least these instances, and possibly others. Such electrode polarity control cannot be achieved with conventional DC power supplies. In fact, when a conventional DC power supply is employed, the only way to change the polarity of the electrodes is to physically disconnect the power supply from the welding gun, and then re-connect the power supply in reverse polarity orientation, which is a time-consuming and laborious process.
SUMMARY
[0007] A programmable polarity module that permits rapid on-demand control of the polarities assigned to the welding electrodes retained on a welding gun is disclosed. The programmable polarity module is electrically connectable to the fixed polarity output lugs of a DC power supply in any known fashion to provide a multi-component DC power supply unit. It is also electrically connectable to the welding gun, and thus the welding electrodes, by way of a first interchangeable polarity output lug and a second interchangeable polarity output lug. The first and second interchangeable polarity output lugs can assign either a positive polarity or a negative polarity to their associated welding electrodes.
[0008] Each of the first and second interchangeable polarity output lugs is associated with a pair of high-amperage silicon controlled rectifiers (SCR's). Within each pair of SCRs, one SCR is associated with a positive polarity and the other SCR is associated with a negative polarity. The pairs of SCR's can thus be controlled to assign each interchangeable output polarity lug—and the welding electrode associated with each lug—with a positive polarity or a negative polarity. This type of control permits the polarity designations of the two welding electrodes to be dictated in any conceivable way so that the particulars of a variety of spot welding processes can be accommodated. The polarity of each welding electrode can even be rapidly switched without having to disconnect the DC power supply from the welding gun.
[0009] The term “high-amperage silicon controlled rectifier” and its abbreviation, “SCR,” as used herein, are meant to broadly encompass a single thyristor or an arrangement of one or more thyristors that act in tandem. Thyristors are electrical switching devices that include alternating p-type and n-type semiconductor layers that can be controlled to permit or block current flow based on the magnitude (or lack thereof) of a voltage applied to a control terminal (also known as a gate). The number of thyristors employed in each SCR depends on the magnitude of the current that needs to be managed through the first and second interchangeable polarity output lugs. For example, each SCR in the pairs of SCR's associated with the first and second interchangeable polarity output lugs may be a single thyristor or, if the current capacity of a single thyristor is not sufficient for whatever reason, an arrangement of several thyristors connected in parallel that, together, can accommodate the magnitude of the current that needs to be controlled.
[0010] The programmable polarity module can be used to cure the effects of an electrode polarity bias that exists within a resistance spot welding process. For example, when spot welding an aluminum alloy workpiece to another aluminum alloy workpiece with a pair of copper alloy electrodes, the current exchanged between the welding electrodes may create a heat differential at the electrode/workpiece interfaces due to the flow of electrons across the aluminum alloy-copper alloy junctions. Specifically, more heat may be generated at the positive welding electrode than at the negative welding electrode, which causes the positive welding electrode to wear at a faster rate. The programmable polarity module could be used here to switch the polarities of the two electrodes every so often, preferably after every spot weld, to keep one electrode from wearing faster than the other.
[0011] As another example, an electrode polarity bias may exist when spot welding dissimilar metal workpieces with a pair of copper alloy electrodes. The dissimilar metal workpieces may be a pair of aluminum alloy sheet metal layers of considerably different thicknesses, or an aluminum alloy sheet metal layer and an aluminum alloy casting, or an aluminum alloy workpiece and a steel workpiece, to name but a few. The spot welding of such dissimilar metal workpieces, like before, may create a heat imbalance at the electrode/workpiece interfaces in which more heat is generated at the positive welding electrode and less heat is generated at the negative welding electrode. Better quality spot welds can generally be achieved by using this heat differential to offset differences in the electrical conductivities and/or the melting points of the dissimilar metal workpieces. The programmable polarity module could be used here to ensure that the welding electrodes are assigned the polarity that results in the best weld quality.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a generalized illustration of a welding gun for use in resistance spot welding applications;
[0013] FIG. 1A is a magnified view of the encircled portion of FIG. 1 identified as 1 A;
[0014] FIG. 2 is a generalized illustration of a welding electrode that can be used to perform resistance spot welding;
[0015] FIG. 3 is a generalized illustration of a DC power supply unit, which includes a DC power supply and a programmable polarity module, that can be carried by the welding gun shown in FIG. 1 ;
[0016] FIG. 4 is a schematic illustration of the programmable polarity module illustrated in FIG. 3 ;
[0017] FIG. 5 is a picture of a welding electrode that has been provided with a negative polarity during repeated spot welding of an aluminum alloy sheet metal layer to another aluminum alloy sheet metal layer;
[0018] FIG. 6 is a picture of a welding electrode that has been provided with a positive polarity during repeated spot welding of an aluminum alloy sheet metal layer to another aluminum alloy sheet metal layer;
[0019] FIG. 7 is a cross-sectional photomicrograph of a resistance spot weld formed between an aluminum alloy sheet metal layer and a steel sheet metal layer in which the welding electrode that engaged the aluminum alloy sheet metal layer had the negative polarity;
[0020] FIG. 8 is a cross-sectional photomicrograph of a resistance spot weld formed between an aluminum alloy sheet metal layer and a steel sheet metal layer in which the welding electrode that engaged the aluminum alloy sheet metal layer had the positive polarity;
[0021] FIG. 9 is a cross-sectional photomicrograph of a resistance spot weld formed between an aluminum alloy sheet metal layer and an aluminum alloy casting in which the welding electrode that engaged the aluminum alloy casting had the negative polarity; and
[0022] FIG. 10 is a cross-sectional photomicrograph of a resistance spot weld formed between an aluminum alloy sheet metal layer and an aluminum alloy casting in which the welding electrode that engaged the aluminum alloy casting had the positive polarity.
DETAILED DESCRIPTION
[0023] FIGS. 1-1A generally depict a welding gun 10 that can be used to resistance spot weld a metal workpiece stack-up 12 at one or more predetermined spot weld sites 14 . The workpiece stack-up 12 includes, for example, a first metal workpiece 16 and a second metal workpiece 18 . These metal workpieces 16 , 18 overlap one another to provide a faying interface 20 at the weld site 14 where the spot welding process forms a weld nugget 22 that metallurgically joins the metal workpieces 16 , 18 together. The term faying interface 20 , as used herein, encompasses instances of direct overlapping contact between the workpieces 16 , 18 as well as instances where the workpieces 16 , 18 may not be touching, but are nonetheless overlapping in close proximity to one another, such as when a thin layer of adhesive, sealer, or some other intermediate material is present. Each of the first and second metal workpieces 14 , 16 may have a thickness 160 , 180 that ranges from about 0.3 mm to about 6.0 mm, and preferably ranges from about 0.6 mm to about 3.0 mm, at the weld site 14 .
[0024] At least one of the first or second metal workpieces 16 , 18 is composed of an aluminum alloy. The aluminum alloy may be an aluminum-magnesium alloy, an aluminum-silicon alloy, an aluminum-magnesium-silicon alloy, or an aluminum-zinc alloy. Some specific aluminum alloys of this kind are 5754 aluminum-magnesium alloy, 6022 aluminum-magnesium-silicon alloy, and 7003 aluminum-zinc alloy. The other of the first or second metal workpieces 16 , 18 may be composed of an aluminum alloy, like the ones just mentioned, or it may be composed of steel. The steel may be a low carbon steel, a galvanized low carbon steel, or a galvanized advanced high strength steel (AHSS). Some specific steels of this kind include interstitial-free (IF) steel, dual-phase (DP) steel, transformation-induced plasticity (TRIP) steel, and press-hardened steel (PHS). The term “metal workpiece” and its aluminum alloy and steel variations are used broadly in the present disclosure to include a sheet metal layer, a casting, an extrusion, and other aluminum alloy or steel pieces that are resistance spot weldable.
[0025] It should be noted that the weld nugget 22 shown in FIG. 1A is a generic illustration that is meant to be representative of the wide variety of weld nugget compositions—and weld nugget locations—that can be formed at the faying interface 20 of first and second metal workpieces 16 , 18 . For example, if the first and second metal workpieces 16 , 18 are aluminum alloy sheet metal layers, the weld nugget formed at the faying interface of the two layers will penetrate into each layer to some extent. A typical penetration depth of the weld nugget into each aluminum alloy sheet metal layer is about 10% to about 80% of the thickness of the layer. As another example, if the first metal workpiece 16 is a steel sheet metal layer and the second metal workpiece 18 is an aluminum alloy sheet metal layer, the weld nugget formed at the faying interface of the two layers will penetrate mainly into the aluminum alloy sheet metal layer, primarily because aluminum alloys melt at a significantly lower temperature than steel. The weld nugget 22 depicted in FIG. 1A is thus intended to represent a more inclusive variety of weld nugget and weld nugget locations than what is generically shown, including the specific examples described here as well as any others that may be formed between the different combinations of workpiece materials that can be employed.
[0026] The welding gun 10 includes a first gun arm 24 and a second gun arm 26 . The first gun arm 24 includes a shank 28 that retains a first welding electrode 30 . Likewise, the second gun arm 26 includes a shank 32 that retains a second welding electrode 34 . The first and second gun arms 24 , 26 may be stationary (pedestal welder) or robotically moveable, as is customary in the art, and are operated during spot welding to press the first and second welding electrodes 30 , 34 against oppositely-facing surfaces 36 , 38 of the first and second metal workpieces 16 , 18 in diametric alignment with one another at the weld site 14 . The clamping force assessed by the gun arms 24 , 26 establishes good mechanical and electrical contact between the welding electrodes 30 , 34 and their respective engaged metal workpiece surfaces 36 , 38 .
[0027] The first and second welding electrodes 30 , 34 are preferably water-cooled copper alloy welding electrodes that include a body 40 and a weld face 42 at the end of the body 40 , as illustrated in FIG. 2 . The weld face 42 is the part of the electrode that contacts the surface 36 , 38 of the metal workpiece 16 , 18 being engaged by the electrode 30 , 34 . And it may incorporate any of a wide variety of designs that are suitable for spot welding an aluminum alloy workpiece or a steel workpiece. If the welding electrode 30 , 34 is intended to engage an aluminum alloy workpiece, for example, the weld face 42 is preferably domed, as shown in FIG. 2 , and may further be smooth, textured, or include surface features such as protruding ringed ridges. Some examples of these types of copper alloy welding electrodes are described in U.S. Pat. Nos. 6,861,609, 8,222,560, 8,274,010, and 8,436,269, and U.S. Patent Application Publication No. 2009/0255908. If the welding electrode 30 , 34 is intended to engage a steel workpiece, the weld face 42 is preferably flat or domed as has long been known in the art. An electrode weld face design that may be used to weld both aluminum alloy and steel workpieces is described in U.S. Pat. No. 8,525,066.
[0028] A DC power supply unit 44 , as shown best in FIG. 3 , is carried by the welding gun 10 . The DC power supply unit 44 supplies a direct current for passage between the welding electrodes 30 , 34 when they are pressed against the oppositely-facing surfaces 36 , 38 of their respective metal workpieces 16 , 18 . This supplied DC is sufficient to initiate a weld pool at the faying interface 20 according to a defined weld schedule. Additionally, the DC power supply unit 44 allows the polarity designations of the first and second welding electrodes 30 , 34 to be controlled. And it can perform these functions while remaining installed on the welding gun 10 . The DC power supply unit 44 includes, as shown, a DC power supply 46 and a programmable polarity module 48 .
[0029] The DC power supply 46 is configured to receive, for example, an input single-phase medium frequency (˜1000 Hz) alternating current (AC) from a weld control (not shown), and to convert that input AC into a higher-amperage welding DC, typically between about 5 kA and about 65 kA, that is supplied to the welding gun 10 . The DC power supply 44 may be any known type that is suitable for conducting resistance spot welding. For example, as shown in FIG. 3 , the DC power supply 44 may be a water-cooled, medium-frequency DC power supply that includes, as an integrated package, a transformer 50 and a rectifier 52 . This type of DC power supply is commercially available from a number of suppliers including ARO Welding Technologies (US headquarters in Chesterfield Township, MI) and Bosch Rexroth (US headquarters in Charlotte, N.C.). Other types of DC power supplies may of course be used, including those configured to receive a single-phase 60 Hz AC.
[0030] The transformer 50 receives the input AC at an input port 54 . The input AC is fed through a primary winding and is “stepped down” to create a lower voltage, higher amperage secondary AC in a secondary winding. This secondary AC is then fed to the rectifier 52 where a collection of semiconductor diodes converts it into the welding DC. The rectifier 52 includes a fixed positive polarity output lug 56 and a fixed negative polarity output lug 58 that are composed of copper, a copper alloy, or some other highly electrically conductive material. These output lugs 56 , 58 deliver the welding DC from the rectifier 52 . Skilled artisans will know and understand the function and operation of the transformer 50 and the rectifier 52 and, as such, a more comprehensive description of these two components and their integration into a single package need not be provided here.
[0031] The programmable polarity module 48 is electrically connectable to the rectifier 52 of the DC power supply 46 . Here, as shown in FIGS. 1 and 3 , the programmable polarity module 48 includes a pair of fixed polarity input lugs 60 . Each of these input lugs 60 is composed of copper, a copper alloy, or some other highly electrically conductive material. One of the input lugs 60 is electrically connectable to the positive polarity output lug 56 of the rectifier 52 and the other is electrically connectable to the negative polarity output lug 58 of the rectifier 52 . When electrically connected, as is the case in FIG. 1 , the input lugs 60 assume the polarity of whichever output lug 56 , 58 they are associated with—i.e., the input lug 60 connected to the fixed positive polarity output lug 56 is afforded a positive polarity (designated positive lug 602 ) and the input lug 60 connected to the fixed negative polarity output lug 58 is afforded a negative polarity (designated negative lug 604 ). Bolting or any other suitable type of connection features may be used to physically fasten the programmable polarity module 48 and the DC power supply 46 together.
[0032] The programmable polarity module 48 is also electrically connectable to the welding gun 10 so that the welding DC can be delivered to the welding electrodes 30 , 34 . The programmable polarity module 48 may include a first interchangeable polarity output lug 62 and a second interchangeable polarity output lug 64 to facilitate such a connection. The first interchangeable polarity output lug 62 is electrically connectable to a first bus bar 66 and the second interchangeable polarity output lug 64 is electrically connectable to a second bus bar 68 . The first and second bus bars 66 , 68 are composed of copper, a copper alloy, or some other highly electrically conductive material, and are configured to electrically communicate with the first and second gun arms 24 , 26 and ultimately the first and second welding electrodes 30 , 34 , respectively. Like before, bolting or any other suitable type of connection features may be used to physically fasten the programmable polarity module 48 and the welding gun 10 together.
[0033] The polarities of the first and second interchangeable polarity output lugs 62 , 64 are not fixed; rather, they can be switched between positive or negative at any time in accordance with any conceivable welding plan. The ability to switch the polarity of the first and second interchangeable polarity output lugs 62 , 64 ultimately permits the polarities of the first and second welding electrodes 30 , 34 to be switched in a corresponding way. This is because the designated polarity of the first and second interchangeable polarity output lugs 62 , 64 establishes a matching polarity of the first and second welding electrodes 30 , 34 . For instance, if the first interchangeable polarity output lug 62 is designated positive and, consequently, the second interchangeable polarity output lug 64 is designated negative, then the first and second welding electrodes 30 , 34 will be designated positive and negative, respectively, until the polarities of the lugs 62 , 64 are switched. And when the polarities of the output lugs 62 , 64 are switched, the polarities of the welding electrodes 30 , 34 will be switched as well in the same way.
[0034] A circuit design that may be incorporated into the programmable polarity module 48 to switch the polarities of the first and second interchangeable polarity output lugs 62 , 64 is shown schematically in FIG. 4 . As shown, a first pair 70 of SCR's (silicon controlled rectifiers) is associated with the first interchangeable polarity output lug 62 and a second pair 72 of SCR's is associated with the second interchangeable polarity output lug 64 . The first pair 70 of SCR's includes a forward positive polarity SCR 74 and a reverse negative polarity SCR 76 . Similarly, the second pair 72 of SCR's includes a forward negative polarity SCR 78 and a reverse positive polarity SCR 80 . The forward positive polarity SCR 74 and the reverse positive polarity SCR 80 are associated with one of the fixed polarity input lugs 60 , and the reverse negative polarity SCR 76 and the forward negative polarity SCR 78 are associated with the other input lug 60 . It should be reiterated that, even though FIG. 4 shows the several SCR's 74 , 76 , 78 , 80 as a single thyristor, each of the forward positive polarity SCR 74 , the reverse negative polarity SCR 76 , the forward negative polarity SCR 78 , and the reverse positive polarity SCR 80 may also be an arrangement of one or more thyristors connected in parallel such that they act in tandem to achieve the same cumulative function as a single thyristor would, but with the added possibility of greater current capacity.
[0035] Each of the SCR's 74 , 76 , 78 , 80 includes a gate 740 , 760 , 780 , 800 . These gates 740 , 760 , 780 , 800 can be controlled to turn their respective SCR's 74 , 76 , 78 , 80 “on” (gated)—which means current can flow through the SCR—or “off” (ungated)—which means current cannot flow through the SCR. Whether the SCR's 74 , 76 , 78 , 80 are turned “on” or “off” depends on whether a voltage is applied to their gates 740 , 760 , 780 , 800 that meets or exceeds a gate voltage, which is typically anywhere between about 1V-10V. To turn any of the SCR's 74 , 76 , 78 , 80 “on,” and to thus permit current flow, a voltage is applied to the relevant gate 740 , 760 , 780 , 800 that is equal to or greater than the required gate voltage. To turn any of the SCR's 74 , 76 , 78 , 80 “off,” and to thus block current flow, no voltage (i.e., 0V) or a voltage that is less than the gate voltage is applied to the relevant gate 740 , 760 , 780 , 800 . A controller 82 may be incorporated into the circuit design to control which SCR's are turned “on” or “off” at any given time. The controller 82 may be a microcontroller of any known kind, and it may interface with the gates 740 , 760 , 780 , 800 through conventional circuitry known to skilled artisans.
[0036] Two modes for turning the SCR's 74 , 76 , 78 , 80 “on” and “off” are applicable here: a forward polarity mode and a reverse polarity mode. In the forward polarity mode, the forward positive polarity SCR 74 and the forward negative polarity SCR 78 are turned “on” while the reverse negative polarity SCR 76 and the reverse positive polarity SCR 80 are turned “off.” This mode coordinates the positive input lug 602 with the first interchangeable polarity output lug 62 and the negative input lug 604 with the second interchangeable polarity output lug 64 . Such coordination assigns a positive polarity to the first interchangeable polarity output lug 62 and a negative polarity to the second interchangeable polarity lug 64 within the context of the electrical circuit shown in FIG. 4 .
[0037] The reverse polarity mode achieves the opposite effect at the interchangeable polarity output lugs 62 , 64 . Specifically, in the reverse polarity mode, the reverse negative polarity SCR 76 and the reverse positive polarity SCR 80 are turned “on” while the forward positive polarity SCR 74 and the forward negative polarity SCR 78 are turned “off.” This mode coordinates the positive input lug 602 with the second interchangeable polarity output lug 64 and the negative input lug 604 with the first interchangeable polarity output lug 62 . Such coordination assigns a positive polarity to the second interchangeable polarity output lug 64 and a negative polarity to the first interchangeable polarity output lug 62 within the context of the electrical circuit shown in FIG. 4 . Table 1 below summarizes the forward polarity mode and the reverse polarity mode as just described.
[0000]
TABLE 1
Polarity of
Forward
Reverse
Forward
Reverse
Polarity of First
Second
Positive
Negative
Negative
Positive
Interchangeable
Interchangeable
Polarity
Polarity
Polarity
Polarity
Polarity Output
Output Polarity
Mode
SCR
SCR
SCR
SCR
Lug
Lug
Forward
ON
OFF
ON
OFF
POSITIVE
NEGATIVE
Polarity
Mode
Reverse
OFF
ON
OFF
ON
NEGATIVE
POSITIVE
Polarity
Mode
[0038] A resistance spot welding process that implements the programmable polarity module 48 will now be described with reference to FIGS. 1 , 3 , and 4 . To begin, the metal workpiece stack-up 12 is located between the first and second welding electrodes 30 , 34 so that the weld site 14 is generally aligned with the electrodes' 30 , 34 opposed weld faces 42 . The metal workpiece stack-up 12 may be brought to such a location, as is often the case when the gun arms 24 , 26 are part of a stationary pedestal welder, or the gun arms 24 , 26 may be robotically moved to locate the electrodes 30 , 34 relative to the weld site 14 of the stack-up 12 . Once the stack-up 12 is properly located, the first and second welding arms 24 , 26 converge to press the weld faces 42 of the first and second welding electrodes 30 , 34 against the oppositely-facing surfaces 36 , 38 of the first and second metal workpieces at the weld site 14 .
[0039] The welding DC supplied by the DC power supply unit 44 is then passed between the first and second welding electrodes 30 , 34 and through the first and second metal workpieces 16 , 18 and across the faying interface 20 . Resistance to the concentrated flow of the welding DC through the metal workpieces 16 , 18 and across the faying interface 20 generates heat at the faying interface 20 at the weld site 14 . This heat initiates a molten weld pool at the faying interface 20 that penetrates into one or both of the workpiece 16 , 18 depending on the composition and nature of the workpieces 16 , 18 . Upon stoppage of the welding DC current, the molten weld pool solidifies into the weld nugget 22 . The first and second welding electrodes 30 , 34 are then refracted from their engaged surfaces 36 , 38 of the metal workpieces 16 , 18 . Next, the workpiece stack-up 12 is re-located between the first and second welding electrodes 30 , 34 at a different weld site 14 , or it is moved away so that another stack-up 12 can be located for spot welding. More spot welds are then formed in the same way.
[0040] The programmable polarity module 48 can designate the polarities of the first and second welding electrodes 30 , 34 as needed to best suit the particular spot welding process being performed. The programmable polarity module 48 can assign a positive polarity to the first welding electrode 30 and a negative polarity to the second welding electrode 34 , or vice versa, and can further switch the polarities of the first and second welding electrodes 30 , 34 at any time. Such flexibility is made possible by controlling which of the SCR's 74 , 76 , 78 , 80 are turned “on” and which are turned “off” Recall that in the forward polarity mode, for instance, the first interchangeable polarity output lug 62 , and thus the first welding electrode 30 , is assigned the positive polarity while the second interchangeable polarity output lug 64 , and thus the second welding electrode 34 , is assigned the negative polarity. The opposite is true in the reverse polarity mode, in which the first interchangeable polarity output lug 62 , and thus the first welding electrode 30 , is assigned the negative polarity while the second interchangeable polarity output lug 64 , and thus the second welding electrode 34 , is assigned the positive polarity.
[0041] The programmable polarity module 48 may be useful when spot welding an aluminum alloy workpiece to another aluminum alloy workpiece with a pair of copper alloy welding electrodes. The aluminum alloy workpieces could be, for example, a pair of aluminum alloy sheet metal layers, one of which is about 3.0 mm thick or less at the weld site 14 . They could also be, as another example, a pair of aluminum alloy castings, one of which is about 3.0 mm thick or less at the weld site 14 . It has been found that repeatedly forming spot welds between such aluminum alloy workpieces with a conventional spot welding set-up—in which one welding electrode has a fixed positive polarity and the other welding electrode has a fixed negative polarity—causes the positive welding electrode to wear at a faster rate than the negative welding electrode. The positive welding electrode may, in some instances, wear approximately twice as fast as the negative welding electrode over the course of forming 30-100 spot welds.
[0042] The wear experienced at the two welding electrodes 30 , 34 is the accumulation of a hard metal reaction product on the weld face 42 that is derived from a metallurgical reaction between the aluminum alloy of the metal workpiece and the copper alloy of the welding electrode. The accumulation of this hard metal reaction product may eventually spill and form pits in the weld face 42 . To visually demonstrate this wear mechanism, FIGS. 5 and 6 show photomicrographs of a fixed negative polarity copper alloy welding electrode and a fixed positive polarity copper alloy welding electrode, respectively, that have been used together to form 100 spot welds in a pair of overlapping 2 mm thick aluminum alloy sheet metal layers. The fixed positive polarity welding electrode ( FIG. 6 ) has plainly experienced more aluminum alloy-copper alloy reaction product accumulation on its weld face. Because of this, the positive welding electrode needs to be periodically redressed to remove the hard metal reaction product, or replaced with a new welding electrode, more often than the negative welding electrode.
[0043] The programmable polarity module 48 can mitigate the above-described polarity bias by periodically switching the polarities of the first and second welding electrodes 30 , 34 . The polarities may be switched each time a certain number of spot welds have been performed. Preferably, the polarities of the first and second welding electrodes 30 , 34 are switched after every 1-5 spot welds, and most preferably after every spot weld. For example, the programmable polarity module 48 may be operated in its forward polarity mode, in which the first welding electrode 30 is assigned the positive polarity and the second welding electrode 34 is assigned the negative polarity, and the welding DC may be supplied to form a first spot weld. Then, after the welding DC has stopped, the programmable polarity module 48 switches to its reverse polarity mode, in which the first welding electrode 30 is assigned the negative polarity and the second welding electrode 34 is assigned the positive polarity, and the welding DC may be supplied to form a second spot weld. The programmable polarity module 48 may then switch back to its forward polarity mode, and so on. This back-and-forth switching of the electrode polarities will even out the rates at which the two welding electrodes 30 , 34 wear and, as a result, increase the amount of spot welds that can be formed with the two electrodes 30 , 34 relative to the conventional fixed electrode polarity spot welding technique.
[0044] The programmable polarity module 48 may also be useful when the spot welding of an aluminum alloy workpiece and a metal workpiece would create a heat imbalance in the workpieces that degrades weldability. For example, an aluminum alloy sheet metal layer and a steel sheet metal layer have different physical characteristics (e.g., melting points, thermal conductivities, hardness, etc.), and when trying to spot weld the two sheet metal layers together with a pair of copper alloy electrodes, a heat imbalance develops as current passes through them. In this case, a greater amount of localized heat is generated in the more electrically resistive steel than the less electrically resistive aluminum alloy. A heat imbalance may also develop when trying to spot weld different types of aluminum alloy workpieces—such as an aluminum alloy sheet metal layer and an aluminum alloy casting—with a pair of copper alloy electrodes. This is because an aluminum alloy casting typically has a higher electrical resistivity than an aluminum alloy sheet metal layer.
[0045] The spot welding of such workpieces, like before, creates a heat imbalance at the electrode/workpiece interfaces in which more heat is generated at the positive welding electrode and less heat is generated at the negative welding electrode. It has been found that the weld quality between the metal workpieces can be affected by controlling the electrode polarities and, by extension, the heat imbalance developed at the welding electrodes 30 , 34 . When spot welding an aluminum alloy sheet metal layer and a steel sheet metal layer, for instance, the ability to switch the polarities of the welding electrodes 30 , 34 allows for the electrode heat imbalance to be used to compensate for the lower electrical resistivity and the lower melting point of the aluminum alloy sheet metal layer. Either the positive welding electrode or the negative welding electrode may engage the aluminum alloy sheet metal layer to generate more or less heat, respectively, so as to obtain better weld nugget penetration, preferably approaching 50%, into the aluminum alloy sheet metal layer. When spot welding an aluminum alloy sheet metal layer to an aluminum alloy casting, the differences in electrical resistivities can usually be counteracted by engaging the more electrically resistive aluminum alloy casting with the negative welding electrode, which experiences less heat generation at the electrode/workpiece interface compared to the positive welding electrode.
[0046] FIGS. 7-10 visually demonstrate the effects that electrode polarity can have on weld quality. FIGS. 7 and 8 are cross-sectional photomicrographs of a 1 mm thick aluminum alloy sheet metal layer and a 0.55 mm thick steel sheet metal layer that have been subjected to spot welding. FIG. 7 shows the effect of engaging the aluminum alloy sheet metal layer (bottom layer) with a copper alloy welding electrode that has been assigned the negative polarity and engaging the steel sheet metal layer (top layer) with a copper alloy welding electrode that has been assigned the positive polarity. Conversely, FIG. 8 shows the effect of engaging the aluminum alloy sheet metal layer (top layer) with a copper alloy welding electrode that has been assigned the positive polarity and engaging the steel sheet metal layer (bottom layer) with a copper alloy welding electrode that has been assigned the negative polarity. As can be seen, in this particular example, engaging the aluminum alloy sheet metal layer with the positive polarity welding electrode ( FIG. 8 ) results in deeper weld penetration.
[0047] FIGS. 9 and 10 are cross-sectional photomicrographs of a 2.5 mm thick aluminum alloy sheet metal layer and a 3 mm thick aluminum alloy casting that have been subjected to spot welding. FIG. 9 shows the effect of engaging the aluminum alloy casting (top layer) with a copper alloy welding electrode that has been assigned the negative polarity and engaging the aluminum alloy sheet metal layer (bottom layer) with a copper alloy welding electrode that has been assigned the positive polarity. Conversely, FIG. 10 shows the effect of engaging the aluminum alloy casting (top layer) with a copper alloy welding electrode that has been assigned the positive polarity and engaging the aluminum alloy sheet metal layer (bottom layer) with a copper alloy welding electrode that has been assigned the negative polarity. Here, it can be seen that a better-quality spot weld was produced when the negative polarity welding electrode, which generates less heat at its workpiece/electrode interface, engaged the more electrically resistive aluminum alloy casting ( FIG. 9 ), as demonstrated by the absence of the large triangular-shaped void formed below the interface of the casting (upper layer) and the welding electrode that can be seen in FIG. 10 .
[0048] The programmable polarity module 48 can accommodate the above-described polarity bias by switching the polarities of the welding electrodes 30 , 34 , as needed, to achieve or maintain good weld quality. For instance, when spot welding a metal stack-up 12 that includes an aluminum alloy sheet metal layer and a steel sheet metal layer, the polarity assignments of the two welding electrodes 30 , 34 will depend on the properties of stack-up 12 and the weld schedule, meaning that the aluminum alloy sheet metal layer could be engaged by either the positive welding electrode or the negative welding electrode depending on the circumstances. If the first and second welding electrodes 30 , 34 are desired to be assigned the positive and negative polarities, respectively, then the programmable polarity module 48 would be operated in its forward polarity mode. If the opposite polarity designations are desired, however, then programmable polarity module 48 would be operated in its reverse polarity mode. Regarding the practice of spot welding a metal stack-up 12 that includes an aluminum alloy sheet metal layer and an aluminum alloy casting, the programmable polarity module 48 could be operated, in many instances, in whichever mode assigns the positive polarity to the welding electrode 30 , 34 that engages the aluminum alloy sheet metal layer.
[0049] The above description of preferred exemplary embodiments is merely descriptive in nature; they are not intended to limit the scope of the claims that follow. Each of the terms used in the appended claims should be given its ordinary and customary meaning unless specifically and unambiguously stated otherwise in the specification. | A programmable polarity module that permits rapid on-demand control of the polarities assigned to the welding electrodes retained on a welding gun is disclosed. The programmable polarity module is electrically connectable to the welding gun and a direct current power supply unit to provide direct current to the welding electrodes for exchange during spot welding. A first interchangeable polarity output lug and a second interchangeable polarity output lug of the programmable polarity module permit the polarities of the welding electrodes to be switched without having to electrically disconnect the module from the welding gun. | 1 |
TECHNICAL FIELD
[0001] The present invention relates generally to conversation mirrors for vehicles. More particularly, the present invention relates to a conversation mirror having two convex elements that are oriented in such a way as to provide front row occupants optimal view of occupants in subsequent rows behind them. The two convex elements may be spherical or aspherical.
BACKGROUND OF THE INVENTION
[0002] In the modern family vehicle there is at least one rear seat and in most mini-vans and sport utility vehicles there is typically more than one rear seat. This additional room is frequently occupied by children. Drivers and front seat passengers have found it difficult to monitor the activities of children in the rear seats. The added passenger room also makes it difficult for a driver or a front seat passenger to carry on a conversation with a rear seat passenger, while trying to maintain some degree of eye contact.
[0003] Recognizing that the conventional rear view mirror does not provide a good solution to this problem, auto manufacturers began offering “conversation mirrors” which are separate from the conventional rear view mirror. The conversation mirror is usually mounted in the ceiling of the vehicle, either as a fixed component or as a component capable of folding into a ceiling-mounted console. While the conversation mirror does generally aid in maintaining eye contact between the driver or front seat passenger and the rear seat passenger, findings suggest that the most valuable feature of the conversation mirror is that the activities of rear-seat children can be monitored by parents seated in the front seats of the vehicle.
[0004] The known conversation mirror comes in two varieties. The first is the single adjustable conversation mirror that is generally small and is made with a relatively large radius of curvature, typically ˜150 mm. This type of mirror is adjusted for and used by only one front row occupant at a time.
[0005] The second variety of known conversation mirrors uses a single, fixed spherical mirror of relatively small radius. While this design permits simultaneous usage by both front row occupants, the image produced has objectionable and pronounced foreshortening effects due to the variation in distance from the viewer to the different second row passengers.
[0006] The utility of both varieties is further compromised by their excessively wide field of view (FOV). This wide field of view produces overly-inclusive and thus unnecessary views as well as small images. Accordingly, as in so many areas of motor vehicle technology, there is room in the art of interior mirrors for advancement.
SUMMARY OF THE INVENTION
[0007] The conversation mirror assembly as provided herein overcomes the limitations and compromises of known technology by using an appropriately-shaped mirror surface. The mirror assembly includes a mirror which has either a spherical surface or an aspherical surface. The phrase “aspherical surface” refers to any surface that deviates from a spherical shape. Optical systems have historically incorporated aspherical surfaces to fulfill optical requirements that would otherwise be difficult and cumbersome satisfy. Aspheric mirrors have been used in vehicle applications as outside mirrors. Such mirrors are generally convex, but they commonly vary in radius of curvature across the horizontal dimension. In outside vehicle mirrors the surface defines a longer radius of curvature on the inboard side than on the outboard side, thus providing a gentle curve on the inboard side and a stronger curve on the outboard side. This relatively complex shape overcomes problems of image magnification and the resultant distance distortion associated with conventional spherical mirrors by producing a larger field of view with reduced distance distortion.
[0008] The conversation mirror assembly as provided herein in its various embodiments is directed to use in passenger compartments of motor vehicles, air craft and boats. More particularly, the conversation mirror assembly as provided herein includes a mirror housing having a mirror support surface. A first aspheric conversation mirror biased toward the driver is fitted to the mirror support surface of the mirror housing. A second aspheric conversation mirror biased toward the front seat passenger is fitted to the mirror support surface of the mirror housing adjacent the first conversation mirror. Both the first conversation mirror and the second conversation mirror have the same aspheric shape. Where the aspheric mirror surface is used the multiple radii defined by the surface optimizes the image by reducing the effect of distance foreshortening.
[0009] In the first embodiment of the invention the first conversation mirror is separate from the second conversation mirror. In an alternate embodiment of the invention, the first conversation mirror and the second conversation mirror define two faces or surfaces of a single mirror with each face or surface defining an aspheric surface.
[0010] Other advantages and features of the embodiments of the invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a more complete understanding of this invention, reference should now be made to the embodiment illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention wherein:
[0012] FIG. 1 illustrates a stylized plan view of an interior of a vehicle and the view perceived by the driver using a conventional conversation mirror;
[0013] FIG. 2 illustrates a stylized plan view of an interior of a vehicle and the views perceived by both the driver and the front seat passenger using a conversation mirror of the present invention;
[0014] FIG. 3 illustrates a sectional view of a first preferred embodiment of a conversation mirror according to the present invention with adjacent spherical mirror surfaces and having an outline of the conventional conversation mirror shown in broken lines;
[0015] FIG. 4 illustrates a sectional view of a second preferred embodiment of a conversation mirror according to the present invention with adjacent spherical mirror surfaces;
[0016] FIG. 5 illustrates a sectional view of a third preferred embodiment of a conversation mirror according to the present invention with adjacent aspherical mirror surfaces;
[0017] FIG. 6 illustrates a perspective view of a variation of the first preferred embodiment of the conversation mirror of FIG. 3 ;
[0018] FIG. 7 illustrates a perspective view of a variation of the conversation mirror of FIG. 6 that includes two halves that are pivotably attached;
[0019] FIG. 8 illustrates a perspective view of the conversation mirror of FIG. 7 but showing one half of the mirror rotated relative to the other half of the mirror;
[0020] FIG. 9 shows a perspective view of a preferred embodiment of a conversation mirror assembly in an overhead console housing according to the present invention;
[0021] FIG. 10 is a partly sectional elevational view of the conversation mirror assembly and overhead console combination shown in FIG. 9 illustrating the mirror assembly in its operative position as well as showing the stored mirror assembly in phantom;
[0022] FIG. 11 is a perspective view of an alternate embodiment of a conversation mirror assembly according to the present invention in which the mirrors are illustrated in their stowed and non-functioning positions;
[0023] FIG. 12 is a sectional view of the conversation mirror assembly of conversation mirror assembly in place in an overhead console and shown in its closed and open positions;
[0024] FIG. 13 is the same view of the conversation mirror assembly shown in FIG. 11 but showing the mirror segments in their deployed and functioning positions;
[0025] FIG. 14 is a top plan view of the conversation mirror assembly shown in FIG. 13 illustrating the mirror segments in their opened positions;
[0026] FIG. 15 is a front view of an additional alternate embodiment of the conversation mirror as set forth herein;
[0027] FIG. 16 is a sectional view of the conversation mirror of FIG. 15 taken along lines 16 - 16 of FIG. 15 ; and
[0028] FIG. 17 is a sectional view of the conversation mirror of FIG. 5 taken along lines 17 - 17 of FIG. 15 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] In the following figures, the same reference numerals will be used to refer to the same components. In the following description, various operating parameters and components are described for one constructed embodiment. These specific parameters and components are included as examples and are not meant to be limiting.
[0030] With reference to FIG. 1 , a stylized plan view of a vehicle interior, generally illustrated as 10 , is shown. The illustrated vehicle interior 10 includes a driver 12 , a front seat passenger 14 , and rear-seat passengers 16 , 16 ′, 16 ″.
[0031] A conversation mirror 18 according to the prior art is illustrated vehicle forward of the driver 12 and the front seat passenger 14 . As is known in the art, the prior art conversation mirror 18 is a single spherical mirror surface. With this configuration, the view in the conversation mirror 18 visible to the driver 12 is overly wide and includes objects outside of the vehicle. This is illustrated by the field of view shown in FIG. 1 . In addition, the different distances between the driver 12 and the rear-seat passengers 16 , 16 ′, 16 ″ produces a foreshortened view that is objectionable to the driver.
[0032] The present invention either a spherical or aspherical mirror surface which overcome the foreshortening and overly-broad field of view of the prior art by providing an optimized and normalized rear view. The aspherical version of the present invention adjusts for foreshortening by introducing a mild distortion and keeps images as large as practicable.
[0033] The arrangement of the conversation mirror of the present invention is shown in FIG. 2 in which a stylized plan of a vehicle interior, generally illustrated as 20 , is shown. The vehicle interior 20 would typically be that of a motor vehicle but may illustrate a marine vehicle or an airplane as well. The illustrated vehicle interior includes a driver 22 , a front seat passenger 24 , and rear-seat passengers 16 , 16 ′, 16 ″. It should be noted that while seating for five individuals is illustrated the number and arrangements of seats may be varied.
[0034] A conversation mirror 28 according to the present invention is illustrated vehicle forward of the driver 22 and the front seat passenger 24 . The conversation mirror 28 may include a spherical mirror surface, an aspherical mirror surface, or a combination of these two surfaces. Regardless of the type of surface, the conversation mirror 28 provides dual mirror faces and any of the conversation mirrors shown in the figures and discussed herein may be of either type of mirror surface. Using the dual mirror face arrangement of the present invention in its various configurations in which each mirror radius is biased toward the front row viewer, the front row occupants have an optimized and normalized view in which foreshortening due to the differences in distance from the viewer to the second row occupants is either reduced or is eliminated. The illustrated fields of view highlight the advantages of the present invention over the single radius design of the prior art. Specifically, the field of view of the driver 22 , illustrated by solid lines, focuses on the passengers 26 , 26 ′, 26 ″ and does not substantially exceed this range. Similarly the field of view of the passenger 24 , illustrated by broken lines, also focuses on the passengers 26 , 26 ′, 26 ″.
[0035] One of the first embodiments of the conversation mirror according to the present invention is illustrated in FIG. 3 in which a conversation mirror assembly, generally illustrated as 30 , is shown in sectional view. The conversation mirror assembly 30 includes a dual mirror face arrangement 32 of a one-piece design which is defined by two mirror faces or surfaces 34 , 34 ′ which are integrated to form the one-piece dual mirror face arrangement 32 . A housing 36 is provided in which a portion of each of the two mirror faces 34 , 34 ′ is fitted. By contrast to the illustrated dual mirror face arrangement 32 , a conventional single radius design mirror surface, illustrated in broken lines as conventional mirror surface 38 , is shown.
[0036] A second embodiment of the conversation mirror of the present invention is illustrated in FIG. 4 in which a conversation mirror assembly, generally illustrated as 40 , is shown in sectional view. The conversation mirror assembly 40 includes a dual mirror face arrangement 42 of a two-piece design which is defined by two mirror faces or surfaces 44 , 44 ′. A housing 46 is provided in which a portion of each of the two mirror faces 44 , 44 ′ is fitted. In addition, a bridge 48 is provided to serve as the central attachment area for the two mirror faces 44 , 44 ′.
[0037] As a further variation to the conversation mirror of the present invention an aspheric two-piece mirror configuration is shown in FIG. 5 . With reference thereto, a conversation mirror assembly, generally illustrated as 50 , is shown in sectional view. The conversation mirror assembly 50 includes a dual mirror face arrangement 52 which is defined by two mirror faces or surfaces 54 , 54 ′. Each mirror face 54 , 54 ′ defines aspheric shapes. By way of example, the radius at point A is different from the radius at point B while all of the points along the curvature of the mirror faces 54 , 54 ′ are progressive and are not constant. For example, the radius at point A may be 105 mm, while a few mm further towards point B it might be 103 mm while at point B the radius might be 101 mm. These examples of radii differences are only examples are not intended as being limiting. By this design configuration a distortion is introduced which is used to counteract the foreshortening effect due to rear-seat passenger distance variation.
[0038] A housing 56 is provided in which a portion of each of the two mirror faces 54 , 54 ′ is fitted. A divider 58 is provided as part of the housing 56 to serve as the central attachment area for the two mirror faces 54 , 54 ′.
[0039] An embodiment of the one-piece conversation mirror of FIG. 3 is illustrated in FIG. 6 in which a dual mirror face arrangement, generally illustrated as 60 , is shown in perspective view. The dual mirror face arrangement 60 is a one-piece element that is defined by two mirror faces or surfaces 62 , 62 ′. The dual mirror face arrangement 60 is pivotable along the Y-axis (cross-car) for adjustment to accommodate various height viewers or second row occupants. To enable the pivoting a pivoting flange 64 is provided on the end of the mirror face 64 and a pivoting flange 64 ′ is provided on the end of the mirror face 64 ′. Each flange 64 , 64 ′ is pivotably attached to a mirror assembly housing (not shown).
[0040] As a variation of the pivoting mirror arrangement of FIG. 6 , a two-piece, dual mirror face arrangement, generally illustrated as 70 , is provided in FIGS. 7 and 8 . The dual mirror face arrangement 70 is a two-piece assembly that includes a first mirror face 72 and a second mirror face 74 . The first mirror face 72 and the second mirror face 74 are pivotably attached at a pivot point 76 . In addition, a pivoting flange 78 is provided on the end of the mirror face 72 and a pivoting flange 80 is provided on the end of the mirror face 74 . Each flange 78 , 80 is pivotably attached to a mirror assembly housing (not shown).
[0041] In operation, each of the first mirror face 72 and the second mirror face 74 of the two-piece, dual mirror face arrangement 70 may be pivoted independently to provide an optimum view for the user. In FIG. 7 the first mirror face 72 and the second mirror face 74 are shown in general alignment with each other. In FIG. 8 the first mirror face 72 and the second mirror face 74 are shown out of alignment as may be desired for use by front seat occupants of different heights.
[0042] The conversation mirror arrangement of the present invention is shown in a housing in FIGS. 9 and 10 . With reference to FIG. 9 , a perspective view of the conversation mirror assembly, generally illustrated as 100 , is shown in its deployed position. The mirror assembly 100 includes a body 102 having a mirror side 104 . The configuration of the body 102 is shown for illustrative purposes only and is not intended as being limiting. Other design configurations could as well be suited for use with the conversation mirror assembly 100 .
[0043] The mirror assembly 100 is operatively associated with a vehicle ceiling 106 . The mirror assembly 100 may be fixed or may be movable relative to the vehicle ceiling 106 . A movable configuration is illustrated such that the mirror assembly 100 assembly is pivotably attached to a mirror-receiving pocket 108 in a known manner. The mirror-receiving pocket 108 is defined in the vehicle ceiling 106 .
[0044] The mirror assembly 100 includes a mirror 110 which is of the dual mirror face arrangement, one-piece design set forth above in FIG. 3 and discussed in conjunction therewith. However, it is to be understood that the mirror 110 may be of any of the configurations discussed above and illustrated in the accompanying figures.
[0045] The dual mirror face arrangement 110 includes a first mirror face 112 and a second mirror face 112 ′. Each of the mirror faces 112 , 112 ′ is biased toward the viewer to provide the front-row occupants with good views of the rear seats of the vehicle.
[0046] The mirror assembly 100 is movable between a deployed position illustrated in FIGS. 9 and 10 and its stowed position illustrated in FIG. 10 in phantom lines. The mirror assembly 100 may be pivotably moved between these two positions by a pivot connection 114 which connects the mirror body 102 to the vehicle ceiling 106 . A latch of the known type may be used to retain the mirror body 102 in the pocket 108 when not in use.
[0047] A variation of the mirror assembly and housing arrangement shown in FIGS. 9 and 10 is illustrated in FIGS. 11 and 12 . With reference thereto, a perspective view of a conversation mirror assembly, generally illustrated as 120 , is shown in perspective view. The conversation mirror assembly 120 includes a body 122 having a mirror side 124 . The configuration of the body 122 is shown for illustrative purposes only and is not intended as being limiting.
[0048] The mirror assembly 120 is operatively associated with a vehicle ceiling 126 as shown in FIG. 11 . The mirror assembly 120 may be fixed or may be movable relative to the vehicle ceiling 126 , however a movable configuration is illustrated in FIG. 11 . The mirror assembly 120 is pivotably attached to a mirror-receiving pocket 127 defined in the vehicle ceiling 126 . A pair of opposed pivot studs 128 , 128 ′ are provided on the mirror body 122 .
[0049] The mirror assembly 120 includes a mirror 130 which is of the dual mirror face arrangement, one-piece design. The mirror assembly 120 may, however, be of any of the configurations discussed above and illustrated in the accompanying figures.
[0050] The mirror assembly 120 includes a first mirror face 132 and a second mirror face 132 ′. Each of the mirror faces 132 , 132 ′ is biased toward the viewer to provide the front-row occupants with good views of the rear seats of the vehicle.
[0051] The mirror body 122 includes an article receiving pocket 134 that is defined in part by a lip 136 . A variety of items such as sunglasses may be stored in the article receiving pocket 134 .
[0052] The mirror assembly 120 is movable between three stopped positions as illustrated in FIG. 12 . These three stopped positions include a deployed, in-use position illustrated in solid lines, a deployed, article-receiving position illustrated in phantom lines, and a stowed position, also illustrated in phantom lines. A latch of a known type may be used to retain the mirror body 122 in the pocket 127 when not in use.
[0053] The mirror assembly illustrated in FIGS. 11 and 12 may be modified as set forth in FIGS. 13 and 14 to provide an optimum view for both the driver and the passenger by allowing for mirror faces that are individually movable. Specifically, a conversation mirror assembly, generally illustrated as 140 , is shown. The mirror assembly 140 is generally of the same function and design as the mirror assembly 120 discussed above and shown in FIGS. 11 and 12 . However, according to the embodiment of FIGS. 13 and 14 , the mirror assembly 140 includes a body 142 having a mirror side 144 . The mirror assembly 140 includes a first mirror face 146 that is hingedly attached to the mirror side 144 and a second mirror face 148 that is hingedly attached to the mirror side 144 . Each of the first and second mirror faces 146 , 148 may be deployed as illustrated in phantom lines in FIG. 14 or may be stowed as illustrated in solid lines in FIGS. 13 and 14 . This arrangement provides both the driver and the passenger with extra flexibility in achieving the optimum view possible.
[0054] An alternate embodiment of the mirror disclosed herein is shown in FIGS. 15 through 17 . The embodiment shown in these figures differs from that shown and discussed above in at least two ways. First, FIGS. 15 through 17 show a mirror assembly that is attached to a windshield instead of to a vehicle ceiling, although it is to be understood that the embodiment of FIGS. 15 through 17 could be attached to the vehicle's ceiling as well. Second, FIGS. 15 through 17 show a mirror assembly in which the dual-radius conversation mirror of the present invention is combined with a conventional rear-view mirror. In these views FIG. 16 is a sectional view of the mirror assembly 150 taken along lines 16 - 16 of FIG. 15 while FIG. 17 is a sectional view of the mirror assembly 150 taken along lines 17 - 17 of FIG. 15 .
[0055] With reference to FIGS. 15 through 17 , a mirror assembly, generally illustrated as 150 , is shown. The mirror assembly 150 includes a mirror body 152 having a mirror side 154 . A conversation mirror portion 156 is provided on the mirror side 154 of the mirror body 152 as is a rear view mirror portion 158 . The rear view mirror portion 158 includes a flat mirror 160 of the type known in the art for use by the driver in observing traffic and pedestrians behind the vehicle. The flat mirror 160 may be of the day-night variety.
[0056] The conversation mirror portion 156 includes a first mirror surface 162 and a second mirror surface 164 . A divider 166 may be provided as part of the conversation mirror portion 156 between the first mirror surface 162 and the second mirror surface 164 as illustrated or the first and second mirror surfaces 162 , 164 may be integral.
[0057] As noted above, the mirror assembly 150 may be attached to either a vehicle front windshield or to the vehicle ceiling. As illustrated in FIGS. 16 and 17 , the mirror assembly 150 is attached to a vehicle windshield 172 by an attachment assembly 174 of the known variety. The attachment assembly 174 is provided for illustrative purposes only, as other attachment assemblies could readily be substituted for that shown.
[0058] The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims. | A conversation mirror assembly is provided for use in passenger compartments of motor vehicles. The conversation mirror assembly includes a mirror housing having a mirror support surface. A first conversation mirror face biased toward the driver is fitted to the mirror support surface. A second conversation mirror face biased toward the front seat passenger is fitted to the mirror support surface adjacent the first conversation mirror. The first conversation mirror face and the second conversation mirror face may be either spherical or aspherical. The first conversation mirror face may be separate from the second conversation mirror face. Alternatively, the first conversation mirror face and the second conversation mirror face define two facets of a single mirror. | 1 |
This application is a continuation of U.S. application Ser. No. 07/055,982, filed May 27, 1987, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to peristaltic pumps, and more particularly to a novel method and means for increasing the pumping accuracy of such pumps, and even more particularly to peristaltic pumps of the linear variety.
Peristaltic pumps of the type described are particularly suited for use in accurately metering and infusing fluids into the bodies of hospital patients, and the like. The U.S. Pat. Nos. 4,217,933, 4,346,705, 4,299,218, and 4,210,138 disclose one type of fluid infusion and metering equipment which is commonly used today in hospitals and other such institutions where extreme accuracy in the infusion of fluids is very important. This system uses a rotary or roller-type peristaltic pump, as disclosed for example in U.S. Pat. Nos. 4,155,362 and 4,210,138.
One major disadvantage of a system of the type noted above is that it is extremely complicated and expensive. The reason for this is that the peristaltic pump, which is the essence of the equipment, operates in the usual manner repeatedly to compress and expand a section of resilient tubing through which the metered fluid is pumped. This tubing typically is made from a flexible, plastic material such as polyvinyl chloride or the like. As is well known to those skilled in the art, the section of the tubing which passes through the peristaltic pump is intermittently compressed and released at spaced points along its length. It is this alternate expansion and contraction of the tubing, which effects the pumping of the fluid. This is true whether the pump is of the rotary type described above, or of the linear variety, such as shown for example in FIG. 4 of the U.S. Pat. No. 4,155,362.
Regardless of the particular type of peristaltic pump employed, its Achilles' heel is the need for utilizing the flexible tubing, the characteristics of which are subject to change in response to ambient temperature variations, fatigue during prolonged use, tubing eccentricity, etc. Motor speed, the speed of the peristaltic rotor or drive shaft is also a source of error during metering, but this factor (the speed of the rotor) can be controlled very accurately by available, inexpensive control devices. However, the variables in the fluid feed rate that are introduced by virtue of the presence of the plastic tubing have been far more difficult to control.
For example, because of fatigue, tubing elasticity and hence its inner diameter can vary rather drastically during use, and as a consequence the metering rate and pumping efficiency will vary accordingly. In practice, many conventional metering systems of the type described have been found to exhibit as much as a 10% drop in flow rate in a twenty-four hour period. By using rather sophisticated control systems of the type disclosed in the above-noted U.S. patents, it has been possible to reduce this drop to as much as 6 to 7%. However, for many infusion systems even this rather limited drop in the flow rate is undesirable if not intolerable.
It is an object of this invention, therefore, to provide a novel method of stabilizing the pumping rates of peristaltic pumps without requiring the use of any particular types of tubing with the pumps.
Another object is to provide improved metering apparatus of the type described which is capable of substantially reducing the undesirable drop in the flow rate of the apparatus heretofore encountered during prolonged use.
It is a further object of this invention to provide improved metering apparatus of the type described which utilizes relatively simple and inexpensive means for substantially increasing the pumping accuracy of the apparatus.
Still another object of this invention is to provide for fluid infusion systems or equipment of the type described improved peristaltic pump means which is capable of increased pumping efficiency even when employing standard, flexible tubing, rather than utilizing any special type of tubing.
Still other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawings.
SUMMARY OF THE INVENTION
The pump employed with the illustrated metering apparatus is a linear peristaltic pump having a plurality of reciprocable pushers or fingers driven at one end by a like plurality of annular cams that are carried by a drive shaft, and engagable at their opposite or operating ends with a section of plastic tubing through which fluid is to be pumped. The section of the tubing is releasably held over or against the operating ends of the fingers by a flat backup plate, which is carried by a door that is mounted on a housing to be swung into a closed position in which it releasably secures the backup plate against the side of the tubing section remote from the fingers.
Normally in prior art devices the fingers, or in the case of a rotary peristaltic pump the associated rollers, repeatedly cause the registering section of tubing to be compressed and expanded during a pumping operation. Each expansion step permits the tubing to return to its normal, cylindrical configuration. The present invention involves designing the pump so that the flexible tubular section which is subjected to compression and expansion is never allowed, from the outset, to assume a truly cylindrical configuration. Instead, the operating cams are designed to maintain the tubular section oval in cross section. This has been found to be effective in considerably reducing the drop in flow rate previously experienced by known metering systems.
THE DRAWINGS
FIG. 1 is a fragmentary side elevational view of part of fluid infusion and metering apparatus having an improved peristaltic pump made according to one embodiment of this invention, portions of the apparatus being cut away and shown in section;
FIG. 2 is a fragmentary sectional view taken generally along the line 2--2 in FIG. 1 looking in the direction of the arrows;
FIG. 3 is a fragmentary sectional view taken generally along the line 3--3 in FIG. 1 looking in the direction of the arrows; and
FIG. 4 is a graphical representation of the new rate of change of the flow rate of this improved metering apparatus, as compared to the rate of change of the flow rate of known such apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings by numerals of reference and first to FIGS. 1 to 3, 10 denotes generally a linear peristaltic pump mechanism which forms part of a fluid infusion or metering system of the type described above. The pumping mechanism 10 comprises a stationary pump body 12, which is secured in a conventional metering housing (not illustrated), such as for example a housing of the type which forms part of the volumetric infusion pump, that is sold by the Assignee of the present invention under the trademark "SIGMA 6000". The body 12, which is generally rectangular in cross section, has in its forward or left end (FIG. 2) a large, rectangular recess 13 that is used for a purpose noted hereinafter. Integral with and projecting rearwardly from the solid central section of the pump body 12 are two, vertically spaced, parallel wings or projections 14 and 15, the marginal side edges of which are connected to the central section of body 12 by two sets of inclined web section 16 and 17, respectively.
Rotatably secured adjacent opposite ends thereof in a pair of annular bearings 18, which are secured in registering openings in projections 14 and 15, is a cam drive shaft 20. Secured to shaft 20 for rotation thereby eccentrically about its axis between the projections 14 and 15 are six annular cams, which in FIG. 1 are denoted by the numerals 21 through 26. These cams register with six, identical operating rods 27, which are mounted to reciprocate intermediate their ends in six spaced, parallel bores 28, which are formed in the central section of body 12. Each bore 28 opens at one end on the bottom of the recess 13 and at its opposite end on a plane, transverse surface 29, which is formed on the rear or right end (FIG. 1) of the central section of the body 12 to extend vertically between the projections 14 and 15 in spaced, confronting relation to the cams 21 through 26.
Each rod 27 has secured on its rear or right end, as shown in FIG. 1, an enlarged-diameter cap 31, which is slidably engaged at its outer end with the peripheral surface of one of the cams 21 through 26, and at its inner end with a compression spring 32, which surrounds each rod 27 between the surface 29 and the associated cap 31. Each spring 32 thus resiliently urges the associated rod 27 toward the right in FIG. 1 relative to body 12, thereby resiliently to retain the associated cap 31 in sliding engagement with the outer peripheral surface of one of the cams 21 through 26.
Secured to the opposite or left end (FIG. 1) of each rod 27 for reciprocation thereby in the recess 13 is one of six, rectangularly shaped, tube-engaging fingers or pushers, which are denoted by the numerals 41 through 46 in FIG. 1. These fingers project through a large rectangular slot or opening 47, which is formed in a cover plate 48 that is secured over the left or outer end of the body 12 by a plurality of screws 49 so that its opening 47 registers with the rectangular recess 13 in body 12.
Secured to plate 48 adjacent the edge of its opening 47, and projecting outwardly from the plate (toward the left as shown in FIG. 1) are four, vertically spaced pairs of combination tube/finger guides denoted at 51, 52, 53 and 54, respectively. As shown more clearly in FIG. 2, the two guides of each pair 51 through 54 are located at opposite sides, respectively of slot 47, and have narrow rib sections 51' through 54', respectively, which are disposed to project slidably into corresponding notches formed in the opposed side edges of at least certain of the fingers 41 through 46. Specifically, the ribs 51' as shown in FIG. 2, project into registering recesses formed in the upper side edges of the finger 41; the ribs 52' project into registering recesses formed in the opposed side edges of the confronting surfaces on fingers 42 and 43; the ribs 53' project into registering recesses formed in opposite sides of the confronting surfaces of fingers 44 and 45; and the ribs 54' project into registering recesses formed in opposite sides of the bottom surface of finger 46. The projections 51 through 54 thus serve slidably to guide the fingers 41 through 46 for reciprocation in predetermined paths upon the rotation of shaft 20, as noted hereinafter.
As shown in FIG. 1, the projections 51 through 54 (only one of each pair of which is shown in FIG. 1) project into registering recesses 61 through 64, respectively, which are formed in a rectangularly shaped, plastic backup plate 65. Plate 65 is mounted on a hinged cover or door 67, which forms part of the above-noted housing for the "SIGMA 6000" pump apparatus, and which is disposed to be swung into and out of an operative position in which it secures the plate 65 releasably in the position as shown in FIG. 1. (Although only one projection 51 through 54 of each pair thereof, and the corresponding registering recesses 61 through 64 are shown in FIG. 1, it will be understood that like recesses 61 through 64 are formed in the plate 65 to accommodate the remaining projections 51 through 54 that extend from plate 48.)
In use, a flexible tube T, through which fluid is to be pumped, is positioned intermediate its ends across the face of the cover plate 48 so that the tube extends (as shown by broken lines in FIG. 2) vertically between the pairs of projections 51 through 54 on plate 47, and in overlying relation to the outer ends of the pushers or fingers 41 through 46. The door 67 is then swung closed, or into the position as shown in FIG. 1, so that the projections 51 through 54 enter the registering recesses 61 through 64 in plate 65, thus allowing plate 65 to engage the registering section of the tube T at the side thereof remote from the fingers 41 through 46. At this time the side of the tube T remote from the cover plate 48 is also engaged by each of six, narrow metal strips 67, which are embedded in and project slightly from the face of plate 65 along transverse lines that register substantially with the midpoints of the opposed fingers 41 through 46, respectively. These strips 67, which are conventional, cooperate with the fingers 41 through 46 during operation of the latter to effect the desired restriction of the tube T.
After the door 67 has been releasably secured in its closed position, the cam shaft 20 is rotated by a motor M which is carefully controlled by a mechanism that forms no part of this invention. As shaft 20 rotates its cams 21 through 26 effect the desired reciprocation of the rods 27 and the pushers 41 through 46 attached thereto. As will be apparent to one skilled in the art, the fingers 41 through 46 are repeatedly extended by the cams 21 through 26 and retracted by springs 32 in order repeatedly and progressively to compress and then release the tubing T in the section thereof denoted at X in FIG. 1, thereby causing fluid in the tube to be pumped unidirectionally through the tube in a known manner. Although this mode of operating a linear peristaltic pump is, generally speaking, well known to the prior art, the pump disclosed herein is unique in that the cams 21 through 26 are designed to manipulate the pushers 41 through 46 in a manner heretofore unknown and unappreciated by the prior art.
For example, as noted above, one of the major problems encountered during the use of flexible tubing in combination with known peristaltic pumps is that the flow rate or output of the pump tends to vary rather considerably during use, and as shown for example in FIG. 4, this variation is greatest during the initial operation of the pump. Tubing durometer and the concentricity of the inner and outer diameters of the tubing are directly responsible for the drop in flow rate accuracy over a period of time. As that portion of the tubing which is located in the pumping section (the portion denoted by X in FIG. 1) is subjected again and again to the pressure of being pinched off or compressed by the pump fingers 41 through 46, it fatigues and loses some of its ability to open back up. Also, if the tubing is nonconcentric its "effective" area may change dramatically for some orientations of the tubing in the pumping section of the pump. As a consequence, this results in a drop in the flow rate delivery over a period of time; and the harder and more eccentric the tubing the more pronounced is the drop. Moreover, as shown graphically in FIG. 4, most of the deformation of the tubing takes place within the first six hours of operating time, and for this reason it is customary normally to design the unit so that it pumps at the outset at a rate slightly greater than the desired rate to compensate for the loss in flow rate which normally occurs as the equipment is utilized over a prolonged period of time.
For example, in FIG. 4 the broken line denotes graphically the percentage in change of the flow rate which occurs in a conventional metering system utilizing known peristaltic pumps. The solid line graph, on the other hand, represents the rate of change which occurs in the flow rate when utilizing applicants' improved pumping mechanism. It will be noted that whereas the percentage of change of the flow rate (old rate) for known metering apparatus ranges from a -6% to approximately a -3%, it has been possible utilizing applicants' equipment to reduce this percentage of change in the rate to the very low range of approximately +2% to approximately 0% change. This significant improvement has been achieved by substantially eliminating or minimizing the very rapid drop in flow rate that heretofore tended to occur during the initial six hours of operation of the equipment.
This improvement has been effected by the above-described equipment by designing the cams 21 through 26 so that when the tube T is inserted in the equipment and the door 67 is closed, the entire section of the tubing T engaged by the pushers 41 through 46--i.e., the section denoted by the letter X in FIG. 1--will be at least partially compressed, so that although the bore in the tube T normally would be circular in cross section, at least for the section X of the tubing its bore will be oval in cross sectional configuration. For example, referring to FIG. 1, finger 46 is shown in its approximately fully retracted position, while finger 44 is shown to be in its approximately fully advanced position, wherein finger 44 has, in essence, compressed the tubing T to a point in which its bore is completely closed in that region which registers with pusher 44. Pusher 46, on the other hand, which is typical of the extreme right hand position which each pusher 41 through 46 is capable of assuming, has not been retracted far engough to permit the tubing T completely to resume its normal, cylindrical configuration. Therefore, as the cams 21 through 26 reciprocate the pushers 41 through 46, the section X of the tubing T will never be allowed at any point therealong to return to its fully, cylindrical configuration.
The result is that the pump mechanism 10 eliminates the need for the tube fully to reopen or resume its cylindrical configuration each time the adjacent finger is withdrawn to a retracted position. By eliminating the need for the tubing to return to its cylindrical configuration after each compression stage thereof applicants' apparatus eliminates the loss in the flow rate which is inherent during the early stages of operation (for example the first six hours) of known peristaltic metering equipment, that is, equipment of the type in which the pump rollers or fingers permit the tubing fully to reopen to its cylindrical configuration after each compression thereof. Since it is possible easily to maintain the speed of rotation of the cam drive shaft 20 to within + or -0.1%, it will be apparent that applicants' invention considerably improves the overall efficiency of operation of peristaltic pumping mechanisms of the type described above, as compared to prior such mechanisms. It will also be apparent, that in connection with the illustrated embodiment, this improvement has been achieved very inexpensively, simply by reducing the throw of the associated cams that drive the tube compressing fingers 41 through 46, and without the need for utilizing complicated or expensive electronic control circuitry. Moreover, it would be applicable to any type of peristaltic pump in which one or more compression members operate to induce fluid flow along a flexible section of tubing by repeatedly contracting the section at a point and cyclically moving the contraction along the tubing section to force fluid along the tube in front of the restriction without permitting any portion of the tubing section to return to its noraml, cylindrical configuration.
From the foregoing, it will be apparent that the present invention provides relatively simple and inexpensive means for considerably increasing the efficiency of peristaltic pumping mechanisms while utilizing conventional, flexible tubing of the type which is readily available in the marketplace, and does not require any special tubing. Moreover, although this invention has been illustrated and described in detail in connection with only one embodiment thereof, it will be apparent that it is capable of still further modification, and that this application is intended to cover any such modifications as may fall within the scope of one skilled in the art or the appended claims. | The efficiency and accuracy of a peristaltic pump is increased simply and inexpensively by controlling the cross sectional configuration of the section of flexible tubing which is operated upon the pump thrust members during a pumping operation. Specifically, the section of tubing, which is normally generally cylindrical in configuration, is held partially constricted or compressed upon being mounted in the pump, so that it becomes generally oval in cross sectional configuration. The thrust members of the pump, when the latter is operating, thus repeatedly compress a section of tubing which is already partially compressed, and which never is allowed to expand fully back to its cylindrical configuration. This substantially reduces the drop in feed rate heretofore experienced by similar pumps because of tubing fatigue and augument. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to the growth of cubic silicon carbide crystals. More specifically, the present invention relates to the growth of cubic silicon carbide by Chemical Vapor Deposition (CVD).
A great need has developed to produce high-temperature electronic devices for advanced turbine engines, geothermal wells, and other applications. Cubic silicon carbide (SiC) is considered an excellent candidate for use as a high temperature electronic material because of its large band gap, good carrier mobility and excellent physical stability. A primary reason, though, why development of cubic SiC has not been carried further is the lack of a reproducible process for producing the single crystal substrates necessary for device fabrication.
A method that attempts to remedy this problem is presented by S. Nishino, J. A. Powell, and H. A. Will, "Production of large-area single-crystal wafers of cubic SiC for semiconductor devices," Appl. Phys. Lett. Vol. 42, No. 5, Pages 460-462, March 1983. However, the method of Nishino et al. results in cubic SiC crystals that are not of a high purity and have poor duplicability. (See A. Addamiano and J. A. Sprague, "Buffer-layer technique for the growth of single crystal SiC on Si," Appl. Phys. Lett. Vol. 44, No. 5, March 1984).
There are several reasons why the method of Nishino et al. is not adequate. Nishino et al. teach etching of the Si substrates, on which the cubic SiC crystals are grown in the apparatus used for the CVD, using hydrogen chloride (HCl) vapor at a temperature of about 1200° C. Etching of the substrates in the CVD reactor with hot HCl vapor results in considerable erosion of the graphite susceptor housing the Si substrates. This, in turn, results in random deposition of carbon particles on the Si substrates, with the consequence that there is poor duplicability of the results and impurities are introduced into the cubic SiC as it is grown. Another reason the method of Nishino et al. is not adequate is because in the formation of a buffer layer of cubic SiC on the Si substrate Nishino et al. teach mixing H 2 and C 3 H 8 at room temperature, flowing the mixture over the Si substrates at room temperature, then bringing the temperature to 1360° C. and maintaining the temperature for about 1 minute, followed by cooling. The buffer layers formed by this technique are stated to be mainly polycrystalline cubic SiC, by Nishino et al., supra. This is because C 3 H 8 is present throughout the heating step causing different growth conditions for cubic SiC that forms as the temperature is raised from room temperature to 1360° C.
Nishino et al. also teach to carry out CVD on the buffer layers at a temperature of about 1360° C. This temperature is not the ideal temperature for formation of perfect cubic single crystal layers.
SUMMARY OF THE INVENTION
Accordingly, one object of the present invention is to provide a novel method for the production of cubic SiC for high temperature electronic devices.
Another object of the present invention is to provide a novel method for the production of highly pure, single crystal cubic SiC that is duplicable.
Another object of the present invention is to provide a novel method for the production of large-area single-crystal wafers of cubic SiC.
These and other objects of the present invention can be achieved by a method for producing large-area cubic SiC wafers comprising the steps of wet-etching an Si substrate for 10-60 seconds; heating the Si substrate to between 1370° C. and 1405° C. in H 2 gas; exposing the Si substrate to C 3 H 8 for 5-30 seconds, after temperature equilibrium in the heating step has been reached, to form a buffer layer of single crystal cubic SiC on the Si substrate, the amount of C 3 H 8 being no greater than 1 percent by volume of the H 2 gas; quenching the Si substrate having a cubic SiC buffer layer in H 2 to room temperature; heating the Si substrate with the SiC buffer layer to between 1370° C. and 1405° C. in H 2 gas; exposing the Si substrate having the buffer layer to C 3 H 8 and SiH 4 , after thermal equilibrium has been reached for 0.25 to 5 hours to make a thicker layer of cubic SiC, the amount of C 3 H 8 and SiH 4 each being no greater than 1 percent by volume of the H 2 gas; quenching the Si substrate having the thicker layer of SiC in H 2 gas to room temperature.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing, wherein:
FIG. 1 is a side view of the apparatus for cubic SiC growth via the CVD process.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawing, wherein like reference numerals designate identical or corresponding parts throughout the several views, and more particularly to FIG. 1 thereof, there is shown an Si wafer (16) of structure (100), e.g., for the preparation of a preform 10 comprised of a layer of cubic SiC 18 deposited atop said highly pure wafer of Si 16. The Si layer 16 during the preparation of the perform is rested atop a graphite susceptor 20 located inside a fused quartz tube 12 and surrounded by an induction coil 15. The induction coil 15 raises the temperature of the graphite susceptor near the Si wafer to about 1400° C. causing a gas mixture that has been introduced upstream into the tube 12, to chemically react and deposit the layer of cubic SiC 18 on the Si wafer 16.
More specifically, CVD is begun by wet etching the silicon substrate prior to its insertion in the reactor 12 followed by rinsing in de-ionized water and drying. The etchant used is a mixture of nitric, hydroflouric and acetic acid usually in the volume ratio 5:3:3, respectively. The etchant is used at room temperature, and the etching time is 10-60 seconds, and preferably 30 seconds.
After the etching process is completed, the Si wafer 16 is placed atop a graphite susceptor 20 located inside a fused quartz tube 12. The susceptor 20 is raised at one edge by post 25 so as little of the susceptor 20 as possible is touching the tube 12. This susceptor 20 is propped up to minimize heat loss by conduction through the tube 12 since the tube 12 is cooler than its interior and acts as a heat sink.
When the Si wafer is in place on the susceptor 20 a stream of pure hydrogen (H 2 ) gas is introduced into the interior of tube 12 housing the Si wafer. The induction coil 15 is turned on and the Si wafer 16 and the area therearound is brought to between 1370° C. and 1405° C. After thermal equilibrium is established in the tube 12, propane gas, C 3 H 8 , is added to the H 2 stream. The C 3 H 8 added to the H 2 stream should be no greater than 1 percent by volume of the H 2 stream. The inclusion of C 3 H 8 in the H 2 stream is for 5-30 seconds and preferably 15 seconds, followed by exclusion of the C 3 H 8 and quenching to room temperature of the Si wafer 16 in pure H 2 . While the C 3 H 8 is present in the tube 12, the carbon in the C 3 H 8 chemically reacts with the Si wafer 16 to form SiC according to the following equations:
C.sub.3 H.sub.8 =3C+4H.sub.2 (I)
3C+3Si=3SiC (II).
At the temperature of between 1370° C. and 1405° C., the SiC that forms is cubic and single crystal. Care should be taken to avoid going higher than 1405° C. because hexagonal, 2H SiC crystals form, or lower than 1370° C. because crystal quality becomes very poor.
After quenching, the Si substrate now supporting the SiC buffer layer is re-heated to between 1370° C. and 1405° C. in pure H 2 gas. Again, thermal equilibrium is allowed to occur after which time silane (SiH 4 ) and propane are introduced into the H 2 that is flowing past the Si substrate with the SiC buffer layer. The amount of SiH 4 in the H 2 should be 1% by volume of the H 2 , and the amount of C 3 H 8 in the H 2 should be 1% volume of the H 2 . The presence of SiH 4 and C 3 H 8 is continued for as long as desired, usually between 0.25 and 5 hours, depending on how thick a cubic SiC layer is wanted. For instance, at 1400° C., the growth rate of cubic SiC on the buffer layer is about 4 m/hr and is large enough to obtain cubic SiC layers of the thickness needed for device fabrication in less than an hour. The presence of C 3 H 8 and SiH 4 in the gas flowing around the Si substrate is discontinued after the desired time has elapsed. The Si substrate with the cubic SiC layer is then quenched in H 2 gas to room temperature. It should be noted that a higher temperature during the CVD process favors formation of more perfect cubic single crystal layers.
A preferred embodiment of many possible embodiments, requires the CVD process to take place in a horizontal, water cooled, rf induction-heated quartz-tube reactor 12 with an internal diameter of 40 mm. An open 35-mm-i.d. quartz liner 33 contains the susceptor 20. The susceptor is machined from high-density, isotropic, high-purity graphite. Prior to the susceptor's first use, it is coated with SiC. The Si substrate 16 rests within a 0.25 mm deep cavity (not shown) in the susceptor 20. The substrate 16 is often (100)-oriented P-type Si, with resistivity of about 150 ohm-cm, measuring 12 mm×25 mm×0.38 mm. The substrate 16 is heated to 1400° C. with a flow of 0.6 liters per minute of H 2 passing around the substrate 16. At thermal equilibrium 0.2 milliliters per minute of C 3 H 8 is added to the flow of H 2 for 15 seconds to form the buffer layer, after which time, the C 3 H 8 flow is discontinued and the substrate 16 is quenched to room temperature in the H 2 gas that has continued to flow. The cubic SiC buffer layer that forms is about 300 A thick.
The substrate with the buffer layer is then heated to 1400° C. in the H 2 gas which is flowing at 1.4 liters per minute through the tube 12. At thermal equilibrium 1.2 milliliters per minute of C 3 H 8 and 0.6 milliliters per minute of SiH 4 are added to the flow of H 2 . This mixture is maintained for 2 hours forming an 8 m thick cubic SiC layer. The C 3 H 8 and SiH 4 flow is the H 2 gas is discontinued and the Si substrate with a cubic SiC layer is quenched to room temperature in the H 2 gas. The Si may be melted at 1420° C. (SiC does not) or the Si may be dissolved in white etch (the SiC does not dissolve) in order to remove the SiC layer 18 from the Si layer 16 after completion of CVD.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A method for chemical vapor deposition (CVD) of cubic Silicon Carbide (SiC) comprising the steps of etching silicon substrates having one mechanically polished face; depositing a thin buffer layer of cubic SiC formed by reaction between a heated Si substrate and a H 2 C 3 H 8 gas mixture; and depositing SiC on the buffer layer at high temperature using H 2 +C 3 H 8 +SiH 4 mixture. | 2 |
This is a division of application Ser. No. 273,461, filed June 15, 1981, now U.S. Pat. No. 4,345,546.
PRIOR ART STATEMENT
This prior art statement is submitted in conformance with Rule 1.98. The most pertinent references of which applicant is aware comprise the following two U.S. Patents.
U.S. Pat. No. 4,036,168 issued 7-19-77 to LALIBERTE
U.S. Pat. No. 3,956,540 issued 5-11-76 to LALIBERTE
Both of these patents deal with essentially the same subject matter, the U.S. Pat. No. 4,036,168 being a Division of U.S. Pat. No. 3,956,540. The patents describe and claim a method and apparatus for coating articles, specifically synthetic resin optical lenses. The apparatus and method are designed to produce a coating of uniform thickness (see U.S. Pat. No. 3,956,540 column 7 lines 48 to 58) on the object. Thus, the objects are lowered into the coating solution at a first controlled rate and removed from the solution at a second (uniform) rate different from the first rate.
SUMMARY OF THE INVENTION
The invention comprises a method for providing a coating to objects such as a lens. A bath of coating solution is provided and the objects are immersed into the solution and removed from the solution at a constantly changing speed. The speed of removal is slower at the top and bottom of the object and faster at the midpoint of the object. Thus the coating is thinner at the top and bottom and thicker at the center (where greater abrasion resistence is required). The slower speed during the removal of the bottom edge of the lens from the solution provides a thin coating and eliminates the formation of coating drip lines and puddles.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a lens with drip lines and puddle resulting from coating according to the prior art methods.
FIG. 2 is a front plan view of the top or power driven portion of my apparatus.
FIG. 3 is a top plan view of the apparatus.
FIG. 4 is a front plan view of the entire coating apparatus.
FIG. 5a is a side view of the apparatus of FIG. 4
FIG. 5b is a diagram illustrating the trigonometric relationships which determine the velocity of the rack.
FIG. 5c is a graph comparing the velocity of the rack to true sinusoidal velocity.
FIG. 6 is a functional diagram of the electronic control system used to control the motion of the apparatus.
FIG. 7 is a cross-section of a lens coated by the method of my invention.
DETAILED DESCRIPTION
Lenses coated according to the methods of the prior art are typically immersed into the coating solution and removed from the coating solution at a constant speed. The speed of immersion may or may not be the same as the speed of removal. It is also well known that for a coating solution of a given viscosity the thickness of the coating varies directly with the speed of removal. Thus greater removal speeds produce coatings of greater thickness. Because thicker coatings exhibit greater resistence to abrasion, it is generally desirable to remove the lenses at relatively high speeds. If an entire lens is removed at the same relatively high speed, defects in the coating occur as shown in FIG. 1. The lens 10 was removed from the coating bath at a uniform and relatively high speed to produce a thick, abrasion resistant coating. The rapid removal of the lens 10 from the coating solution caused excess coating solution to adhere to the lens. When the lens 10 was completely removed from the coating solution, excess solution had not finished draining off the lens. As a result a puddle of coating solution formed and as the puddle slowly grew and dripped off the lens, a series of drip lines 12 formed on the lens. Because the bottom of the lens was not in contact with the coating solution when the last drop of excess coating solution was ready to drain from the lens, it remained on the lens and hardened forming a puddle 14. Defects such as drip lines 12 and puddles 14 unacceptably distort the optical qualities of a lens 10.
By practicing my invention I have found that I can substantially eliminate drip lines and puddles. I have noted that most lens abrasion occurs in the central portion of a lens. Thus it is really only necessary to apply a relatively thick coating near the center of a lens. I have also discovered that by removing the bottom edge of a lens from the coating solution at a very slow speed, the draining excess coating solution has sufficient time to drain to the bottom of the lens and to be drawn off the lens by the surface tension of the coating solution bath. Thus, the last drop of excess solution does not remain on the lens and no puddle 14 forms.
My method for coating lenses is implemented by the coating device, shown in various views, in FIGS. 2 through 5. The coating device is controlled by the control system 600 illustrated functionally in FIG. 6.
The heart of my invention resides in providing the emerging lens with a velocity of removal profile which is nearly sinusoidal. Thus the velocity is less when the top and bottom edge of the lens passes through the surface of the coating solution and gradually increases to a maximum velocity as the center of the lens emerges from the surface of the coating solution.
FIGS. 2 through 5 illustrate the motion control device used to generate such a velocity profile.
The motion control device 20 controls the vertical velosity, of cords 22, indicated by double headed arrows 24 in FIG. 4. A lens rack 26 is suspended from the cords 22. A plurality of lenses 28 are hung in the rack 26. A container 30 holds a volume of coating solution 32 directly beneath the rack 26 and lenses 28. By causing the cords 22 to move vertically upward and downward a sufficient distance, the plurality of lenses 28 will be caused to move from a first position A, where the lenses 28 are entirely above the surface 33 of coating solution 32, to position B where the lenses 28 are entirely below the surface 33. The velocity with which any point on a lens passes through the surface 33 is determined by the velocity profile given to cords 22 by the motion control device 20.
As stated above, the thickness of the coating applied to a lens is dependent upon the speed with which the lens is removed from the coating solution. To achieve a lens coating with the desirable qualities discussed above it is necessary to have a low velocity of removal at the top and bottom edges of the lens and a relatively fast velocity near the center of the lens. Since the coating is formed as the lens emerges, once the lens has completely emerged from the coating solution it is desirable to prevent the lens from re-entering the coating solution. The motion control device 20 is therefor provided with a means for detecting the complete emergence of the lenses 28 upon such detection to raise the rack 26 vertically upward a distance P such that the continued vertical up and down motion of the cords 22 will not cause any part of the lenses 28 to reenter the coating solution 32. This is assured if the distance P is greater than the distance D representing the limits of excursion of the lenses and rack 26 during the coating of the lenses 28. This distance D will be given a more definite physical dimension below in connection with the discussion of the motion control device 20. The rack 26 moves the distance P as it moves from position E to position F. This movement of rack 26 occurs when piston 36 moves from position G to position H, raising pivotable frame member 38 and attached pulleys 40, which in turn causes cords 22 to raise rack 26.
The nature of the motion of cords 22 is determined by the motion control device 20 shown in various views in FIGS. 2 through 5. One end of each cord 22 is attached to a slip ring 50 mounted over cross bar 52. Each end of cross bar 52 is rigidly secured to a respective rotatable disk 54. One disk 54 is rotationally driven by a motor 56 through drive train 58. The other disk 54 is slaved to the rotation of the driven disk by cross bar 52. Thus, as the disks 54 rotate, the ends of cords 22 attached to slip rings 50 will follow a circular path most easily visualized in FIG. 5a. The diameter of the circular path of travel of the ends of cords 22 is equal to D, which is identical to the distance D between lens positions A and B. Thus, to ensure that the lenses 28 are fully immersed in coatingg solution 32, D must be at least slightly greater than the diameter of the lenses 28. Distance D is controlled by the radial position at which the ends of cross bar 52 are secured to disks 54. A plurality of mounting recesses 55 are provided in disks 54, at various preselected radial distances, so that the cross bar 52 may be set to the various distances thereby permitting selection of distance D.
By appropriate placement of pulleys 40 and 42, the movement of rack 26 is constrained to purely vertical movement, even though the ends of cords 22 follow a circular path. Elementary trigonometric analysis can be used to derive the nature of the motion of rack 26 and lenses 28. If the disk 54 is driven to rotate at an angular velocity of ω (omega) radians per second, then the velocity of the rack 26, and hence of the lenses 28, can be shown to be
ωD/2sinαcosβ (1)
where D is the diameter of the circular path traveled by the cross bar 52, α is the instantaneous angular displacement of the disk 54 from time zero (t=0), and β is the instantaneous angular displacement of cord 22 about pivot point PP measured from the reference time (t=0) (where β=0). Of course, if the distance from PP to the center of disk 54 is known, then β can be written in terms of α. If the distance from PP to the center of disk 54 is some number of times greater than r, say nr, then ##EQU1##
for α measured positive in the counterclockwise direction from the point t=0.
From FIG. 5b it is apparent that the angle β reaches a maximum when: ##EQU2## when β is maximum, cosβ max is minimum. For n=2, cosβ max =0.866, hence, from (1 ),
ωD/2sinαcosβ
is always within 0.866 of being equal to ωD/2sinα and the velocity of rack 26 is approximately sinusoidal. When n=3, cosβ max =0.9428, and hence ωD/2sinαcosβ is always within 0.9428 of being equal to ωD/2sinα and the velocity of rack 26 is even more closely sinusoidal.
As n increases the velocity of rack 26 gets closer and closer to being equal to ωD/2sinα, i.e. more nearly sinusoidal. At n=6, cosβ max =0.9860.
A graph of ##EQU3## is shown in FIG. 5c for easy comparison with sin α.
Because the rack 26 is suspended from cord 22 which runs over pulley 42 (see FIG. 5a) which is forward of pulley 40, the motion of rack 26 is always purely vertical.
Once the lenses 28 have been coated and have fully emerged from coating solution 32, i.e. the lenses 28 have risen from position B to position A, some method must be employed to prevent the lenses 28 from reentering the coating solution. One approach could be to stop the rotation of disks 54 just as position A is reached. An alternative approach has been adopted. A microswitch 100 (see FIGS. 5a and 6) is positioned to be contacted by a pin 102 when lenses 28 are in position A. This is the position the lenses 28 reach after they have been coated. The rack 26 is then in corresponding positon E. When the microswitch 100 is activated, a signal is sent to air cylinder 64 to drive piston 36 upward. The piston 36 acts against adjustable arm 66 mounted on frame 38 to drive the frame, pivoted about the axis of pulley 44, upward at its forward end from position G to position H. This pivoting raises the rack 26 further, and raises it a distance (P) such that the continued rotation of disks 54 will not cause any portion of lenses 28 to reenter coating solution 32, thus P is somewhat greater than D.
Once the frame 38 has been raised, an operator may remove the rack 26 at a convenient time and replace it with fully loaded rack of uncoated lenses. The operator then manually activates a switch to cause the air cylinder 64 to retract piston 36. Ideally, the frame 38 should be lowered just prior to the cross-bar 52 reaching the t=0 position shown in FIG. 5. This will assure that the rack 26 and lenses 28 are approximately at positons E and A (see FIG. 4) respectively when the frame reaches position G. The lenses 28 are then at the beginning of their dipping cycle, just ready to be lowered into the coating solution 32. While the lowering of the frame 38 may be triggered manually, it is preferable to devise appropriate electrical switching apparatus to automatically lower the frame 38 such that as the frame reaches position G, the lenses 28 reach position A, ready to begin entering the coating solution.
An automatic mechanism for raising and lowering the frame 38 might comprise a microswitch 100 activated by a pin 102 mounted on a disk 54 such that the pin 102 reaches exactly its lowest position when the cord 22 reaches position t=0, i.e. the lenses 28 would be at their "rest" position at the top of their dipping cycle. One trip of microswitch 100 would activate the air cylinder 64 to raise the piston 36 and frame 38, the next trip of the switch would lower the piston and frame. Since one revolution of disk 54 is typically a minute or so, an operator would have plenty of time to remove a rack of coated lenses and reload with a rack of uncoated lenses, even with the disks continuing to rotate. Alternatively, the microswitch 100 could also trigger a mechanism to stop rotation of the disk 54 when the piston was not at its lowest position.
Because with each coating of lenses, some quantity of coating solution is removed from the container 30, an adjustment means, adjustable arm 66, is provided to fine tune the distance of frame 38 above the surface 33 of the coating solution. The adjustable arm 66, as best illustrated in FIGS. 2 and 5, comprises a thumbscrew 68 threaded in arm 70 of frame 38, with the bottom of the thumbscrew resting on top of piston 36. Clockwise rotation of thumbscrew 68 raises frame 38 above the piston 36 and hence also raises the rest position of lenses 28 (at the peak of their path of travel) above the surface 33. Counterclockwise rotation brings the lenses 28 closer to surface 33. As the level of coating solution lowers due to coating of lenses, counterclockwise rotation of thumbscrew 68 will adjust the "rest" height of the lenses 28 above surface 33 to remain relatively constant and thereby insure uniform coating of multiple racks of lenses.
To insure that the "thickness" of the coating of the lenses keeps the same profile from one rack of lenses to the next, it is necessary to accurately control the speed of the drive motor 56. This may be accomplished in a number of ways with one such way schematically illustrated in FIG. 6. There, device 80 senses the output rotational velocity of the motor shaft and generates a signal proportional thereto, which is provided to a commercially available electronic motor speed controller 82. The controller 82 compares the motor speed represented by the provided signal with the preselected speed dialed into the controller 82. The comparison produces an error signal which drives the motor speed adjustment device 84 to change the motor speed and drive the error signal to zero.
By proper adjustment of the rotational speed of motor 56 and hence of disks 54 and cross bar 52, a lens coating having a profile substantially as shown in FIG. 7 can be obtained. At the top and bottom of the lens 10, the coating may be approximately 2 microns thick, while at the center it will be about 6 microns. For a given viscosity of coating solution, the thickness of the coating can be adjusted by adjusting the speed of motor 56. The thickness profile will remain approximately sinusoidal as illustrated by the graphs in FIG. 5c.
Typically, the motor 56 may be a Bodine motor, such as model NH 12, a 1/50 HP model. A 432:1 gear reduction is used. At 100 RPM of the motor, we have a disk 54 velocity of 0.2315 RPM or 4.32 minutes for 1 revolution. If the cross bar is set for a circular path 80 mm in diameter, then the rack 26 will travel 160 mm in 4.32 minutes (about 1.458 inches in 1 minute for an average speed). Use of other motor speeds will change the thickness of the coating, but the coating profile will remain approximately sinusoidal. At a more typical motor rotational speed of 450 RPM, we have a disk velocity of 1.04717 RPM or an average linear velocity of 166,67 mm per minute (6.562 inches per minute average). At a rotational speed of 300 RPM, using a coating solution 32 typical of which is Q9-6312 A.R.C. available from Dow Corning, at 10 degrees C. having a viscosity of 22 centipoises, an edge coating of 3 microns thickness and a center coating of 9 microns thickness was obtained.
While the invention has been described with particular reference to the coating of optical lenses, it is obvious that the invention is not limited to optical applications. The descriptions and FIGS. 1 through 7 are intended as merely illustrative of a particular embodiment and application of the invention, and should not be interpreted in a limiting sense, but rather as descriptive only. It is contemplated that many changes in both materials and structure may be made without departing from the spirit and scope of the invention which is intended to be limited only by the scope of the appended claims. | The invention comprises a method for providing a coating to objects such as a lens. A bath of coating solution is provided and the objects are immersed into the solution and removed from the solution at a constantly changing speed. The speed of removal is slower at the top and bottom of the object and faster at the midpoint of the object. Thus the coating is thinner at the top and bottom and thicker at the center (where greater abrasion resistence is required). The slower speed at the removal of the bottom edge of the lens from the solution provides a thin coating and eliminates the formation of coating drip lines and puddles. | 1 |
FIELD OF THE INVENTION This invention relates to actuators which convert linear motion to rotational motion and vice versa.
BACKGROUND OF THE INVENTION
[0001] There are many mechanical systems requiring the conversion of linear motion to rotational motion. In one example, a robot forearm may need to rotate using an actuator within an upper arm connected to a shoulder. Helical gears (See. U.S. Pat. No. 5,447,095) are heavy and complex. Some actuators have a limited range of motion. Other actuators occupy too much space. Some suffer from high friction.
SUMMARY OF THE INVENTION
[0002] Aspects of the invention may provide for an actuator which is lightweight, involves few moving parts, and has a range of motion adaptable for numerous applications. The actuator has a form factor which is long and slender and may include rolling elements with low friction. In some examples, an actuator is provided with a range of motion greater than 360°. The actuator may be back drivable and can be used as a differential. in some aspects, the actuator can be designed with integral internal fluid routing using, for example, slip rings.
[0003] Featured are counter-rotating helical cams in the form of inner and outer sleeves, each with at least a pair of helical slots therethrough. A driver includes bearing surfaces received through the helical slots of the inner and outer sleeves.
[0004] Featured is an actuator comprising an outer sleeve with at least a pair of helical slots running in a first direction an inner sleeve with at least a pair of helical slots running in a second, opposite direction and a driver including bearings received through the helical slots of the inner sleeve and into the helical slots of the outer sleeve.
[0005] The helical slots of the sleeves may wrap partially around or more. The helical slots of the inner and outer sleeve may have a constant but different pitch, or a non-constant and different pitch. There can be at least four helical slots in the outer sleeve and four helical slots in the inner sleeve.
[0006] The driver may include a cross-member supporting the bearings thereon and a piston extending from the cross-member. In one design, there are a pair of roller bearings on each end of the cross-member, one inner roller bearing of each pair for a helical slot in the inner sleeve, one outer roller bearing of each pair for a helical slot in the outer sleeve. The bearings can be cylindrical bearings. If the slots are tapered, the bearings can be conical bearings. The driver may be hydraulically driven, electrically driven, or mechanically driven.
[0007] The driver may include at least two cross members.
[0008] The subject invention, however, in other embodiments, need not achieve all these objectives and the claims hereof should not be limited to structures or methods capable of achieving these objectives.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0009] Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which:
[0010] FIG. 1 is a schematic view of a robot arm showing a use of the actuator of the subject invention in one particular example;
[0011] FIG. 2 is a cross-sectional view of an example of an actuator in accordance with the invention;
[0012] FIG. 3 is a schematic three dimensional front view of the actuator of FIG. 2 ;
[0013] FIG. 4 is a schematic three dimensional view of the actuator of FIGS. 2-3 ;
[0014] FIG. 5 is a schematic cross-sectional view of the actuator of FIGS. 2-4 ;
[0015] FIG. 6 is a schematic view showing an example of a tapered helical slot in a sleeve and a conical roller bearing in accordance with examples of the invention;
[0016] FIG. 7 is a schematic three dimensional front view of the outer sleeve of the actuator;
[0017] FIG. 8 is a schematic three dimensional front view of the inner sleeve of the actuator;
[0018] FIG. 9 is a schematic three dimensional cross-sectional view of the coaxially nested actuator sleeves;
[0019] FIG. 10 is a schematic three dimensional front view of another actuator in accordance with an example of the invention;
[0020] FIG. 11 is a schematic three dimensional front view of the driver for the actuator of FIG. 10 ; and
[0021] FIG. 12 is a schematic three dimensional front view of another example of an actuator in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Aside from the preferred embodiment or embodiments disclosed below, this invention is capable of other embodiments and of being practiced or being carried out in various ways. Thus, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. If only one embodiment is described herein, the claims hereof are not to be limited to that embodiment. Moreover, the claims hereof are not to be read restrictively unless there is clear and convincing evidence manifesting a certain exclusion, restriction, or disclaimer.
[0023] FIG. 1 shows a robot arm 10 with actuator 12 inside upper aim 14 and configured to rotate forearm 16 . This is but one use for actuator 12 . It may be used in a variety of systems where linear to rotary motion conversion is required (and vice versa). The actuator can also be used as a differential. In one specific example, piston shaft 11 is a component of a linear driver for actuator 12 and piston shaft 11 is hydraulically driven via hydraulic cylinder 18 . In other examples, the driver may be electrically driven or mechanically driven. A linear voice coil motor, for example, is possible.
[0024] FIGS. 2-5 show actuator 12 comprising outer sleeve 20 and inner sleeve 22 . Outer sleeve 20 includes a pair of helical slots 24 a and 24 b through the wall of the sleeve. Inner sleeve 22 also includes a pair of helical slots 26 a and 26 b coiled in the opposite direction of the helical slots 24 a and 24 b in the outer sleeve. Driver 30 includes, in this example, cross-member 32 attached to piston shaft 11 and supporting outer roller journal bearings 34 a and 34 b riding in helical slots 24 a and 24 b, respectively, in outer sleeve 20 and inner roller bearings 36 a and 36 b riding in helical slots 26 a and 26 b, respectively, of inner sleeve 22 . In other designs, the bearing surfaces on the ends of the cross member can include rolling or sliding elements, journal bearings, and sliding shoes of different shapes. If inner sleeve 22 is fixed, linearly driving piston shaft 11 causes outer sleeve 20 to rotate. Conversely, if outer sleeve 20 is fixed, inner sleeve 22 will rotate as piston shaft 11 moves (up and down in the figures).
[0025] The helical slots in each sleeve may wrap around their respective sleeves partially, once, or more. They may have a constant pitch as shown. The slots of the inner sleeve may have a different pitch than the slots of the outer sleeve. The helical slots of the outer and inner sleeve may also have a non-constant pitch and again the pitch of the helical slots in the outer sleeve is typically different than the pitch of the helical slots in the inner sleeve creating a non-linear transmission.
[0026] FIG. 6 shows a design where helical slot 14 b ′ in outer sleeve 20 has a tapered profile and roller bearing 24 b ′ is conical in shape to match the tapered profile of the slot it rides in. The helix slots of both sleeves may be configured in this fashion and all the roller bearings may be conical in shape.
[0027] FIG. 7 shows outer sleeves with helical sots 24 a and 24 b. FIG. 8 shows inner sleeve 22 with helical slots 26 a and 26 b. FIG. 9 shows both sleeves coaxially disposed in a nested fashion without the driver.
[0028] FIG. 10 shows a design with a driver including two spaced offset cross members 32 a and 32 b for backlash reduction. The driver is also shown in FIG. 11 . Here, the bearing surfaces on the ends of the cross members slide in their respective slots in the sleeves.
[0029] FIG. 12 shows a design where outer sleeve 20 ′ includes four-start helix pattern (four helical slots) as does inner sleeve 22 ′. The driver may include two cross members or four.
[0030] By integrating internal fluid routing and slip rings, hydraulic fluid can be provided downstream of the actuator, for example, to one or more components in forearm 16 , FIG. 1 .
[0031] The resulting actuator in its various embodiments is lightweight, involves few moving parts, and has an adjustable range of motion suitable for numerous applications. The preferred actuator has a form factor which is long and slender and includes rolling elements with low friction.
[0032] Although specific features of the invention are shown in some drawings and not in others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. The words “including”, “comprising”, “having”, and “with” as used herein are to be interpreted broadly and comprehensively and are not limited to any physical interconnection. Moreover, any embodiments disclosed in the subject application are not to be taken as the only possible embodiments.
[0033] In addition, any amendment presented during the prosecution of the patent application for this patent is not a disclaimer of any claim element presented in the application as filed: those skilled in the art cannot reasonably be expected to draft a claim that would literally encompass all possible equivalents, many equivalents will be unforeseeable at the time of the amendment and are beyond a fair interpretation of what is to be surrendered (if anything), the rationale underlying the amendment may bear no more than a tangential relation to many equivalents, and/or there are many other reasons the applicant can not be expected to describe certain insubstantial substitutes for any claim element amended.
[0034] Other embodiments will occur to those skilled in the art and are within the following claims. | An actuator includes an outer sleeve with at least a pair of helical slots coiling in a first direction, an inner sleeve with at least a pair of helical slots coiling in a second, opposite direction, and a driver including bearings received through the helical slots of the inner sleeve and into the helical slots of the outer sleeve. | 8 |
FIELD OF THE INVENTION
The present invention relates to a zinc-sulfophosphate glass exhibiting an extremely low softening point of about less than 300° C. and exhibiting excellent resistance to moisture attack.
BACKGROUND OF THE INVENTION
Considerable research has been conducted in the past to devise inorganic glasses exhibiting low transition temperatures (Tg), thereby enabling melting and forming operations to be carried out at low temperatures with consequent savings in energy costs. As conventionally defined, the transition temperature of a glass is that temperature at which notable increase in thermal expansion coefficient is recorded, accompanied by a change in specific heat (C p ). More recently, it has been recognized that glasses demonstrating low transition temperatures are potentially useful materials for a host of applications including low temperature sealing glasses and glass-organic polymer composites. A very recent development disclosed in U.S. Pat. No. 5,043,369 (Bahn et al.) involves the production of glass-organic polymer alloys. Those alloys are prepared from a glass and a thermoplastic or thermosetting polymer having compatible working temperatures. Thus, the glass and the polymer are combined at the working temperature to form an intimate mixture; that is, the glass and polymer are in a sufficiently fluid state to be co-formed together to form a body displaying an essentially uniform, fine-grained microstructure in which, desirably, there is at least partial miscibility and/or a reaction between the glass and the polymer to promote adhesion and bonding therebetween. An article is shaped from the blend and then cooled to room temperature. Such articles exhibit chemical and physical properties comprising a complementary blend of those demonstrated by the particular glass and polymer. For example, the alloys frequently display a combination of high surface hardness, high stiffness, and high toughness. Alloys are distinguished from glass/organic polymer composites in that there is at least partial miscibility and/or a reaction between the glass and polymer which condition(s) is absent in glass/polymer composites.
Glasses having base compositions within the general zinc phosphate system have been found to be especially suitable for the glass component of glass-polymer alloys. Two illustrations of recent research in that composition system are reported below.
U.S. Pat. No. 4,940,677 (Beall et al.) discloses glasses exhibiting transition temperatures below 450° C., preferably below 350° C., consisting essentially, in mole percent, of at least 65% total of 23-55% ZnO, 28-40% P 2 O 5 , and 10-35% R 2 O, wherein R 2 O consists of at least two alkali metal oxides in the indicated proportions selected from the group of 0-25% Li 2 O, 0-25% Na 2 O, and 0-25% K 2 O, and up to 35% total of optional constituents in the indicated proportions selected from the group of 0-6% Al 2 O 3 , 0-8% B 2 O 3 , 0-8% Al 2 O 3 +B 2 O 3 , 0-15% Cu 2 O, 0-5% F, 0-35% PbO, 0-35% SnO, 0-35% PbO+SnO, 0-5% ZrO 2 , 0-4% SiO 2 and 0-15% MgO+ CaO+SrO+BaO+MnO, consisting of 0-10% MgO, 0-10% CaO, 0-10% SrO, 0-12% BaO, and 0-10% MnO.
U.S. Pat. No. 5,071,795 (Beall et al.) illustrates glasses exhibiting transition temperatures no higher than 350° C. consisting essentially, in mole percent, of about 0-25% Li 2 O, 25-50% ZnO, 5-20% Na 2 O, 0-3% Al 2 O 3 0-12% K 2 O, 25-37% P 2 O 5 0-10% SrO, with the amount of Li 2 O+Na 2 O+K 2 O ranging from 15-35%. In addition, the composition may include 0.5-8% Cl and 0-5% F, as analyzed in weight percent, and up to 10% Cu 2 O, up to 3% SiO 2 , and up to 8% total of at least one alkaline earth metal oxide may be included.
The above-described zinc phosphate glasses demonstrate relatively excellent resistance to chemical attack when compared to other phosphate-based glasses. Nevertheless, the search has been continuous to discover new glass compositions manifesting low transition temperatures with even greater chemical durability. Not only would these lower temperature glass compositions result in lower energy costs attributed the glass formation, they would also result in lower costs attributed to formation of glass/polymer alloys and composites. In addition, lower temperature durable glasses would also increase the number of compatible polymers available which could be co-processed with the glass to form glass/polymer composites and thermally co-deformed with the glass to form glass/polymer alloys. These factors, lowered formation cost and increase in potential polymers choices, would, in turn, likely increase the number of potential commercial applications.
SUMMARY OF THE INVENTION
The above described research has led to the invention of a glass exhibiting a transition temperature normally below about 300°, a working temperature below about 400°, while, at the same time, exhibiting excellent resistance to attack by water.
More specifically, the present invention discloses a glass consisting essentially in terms of mole percent on the oxide basis, of 15-35% P 2 O 5 , 1-25% SO 3 , 30-55% ZnO, 0-25% R 2 O, wherein R 2 O is selected from the group consisting of 0-25% Li 2 O, 0-25% Na 2 O, and 0-25% K 2 O. Additionally, up to a total of 15% of optional ingredients in the indicated proportions may be selected from the group consisting of 0-10% Al 2 O 3 , 0-10% MgO, 0-10% CaO, 0-10% SrO, 0-10% BaO, 0-10% MnO, 0-10% transition metal oxides and 0-15% Cl+F, as analyzed in weight percent.
Whereas complete conversion of the above inventive composition ranges expressed in terms of mole percent to ranges expressed in terms of weight percent is not mathematical possible, the following are the inventive compositions as expressed in terms of approximate weight percent: 25-50% P 2 O 5 , 1-20% SO 3 , 26-45% ZnO, 0-20% R 2 O, wherein R 2 O is selected from the group consisting of 0-8% Li 2 O, 0-20% Na 2 O, and 0-20% K 2 O. The group from which the optional ingredients may be selected from, as expressed in terms of approximate weight percent, is as follows: 0-10% Al 2 O 3 ,0-5% MgO, 0-5% CaO, 0-10% SrO, 0-15% BaO, 0-10% MnO, 0-15% transition metal oxides and 0-15% Cl+F, as analyzed.
PRIOR ART
U.S. Pat. No. 4,544,695 (Meyers) discloses a flame and/or smoke retardant polymeric composition which includes a phosphate-sulfate glass composition containing the following components: 4-18% K 2 SO 4 , 8-36% ZnSO 4 , 4-18% Na 2 SO 4 , and 19-56% P 2 O 5 . In addition, the glass may include the following optional components: 0-25% ZnO, 0-4% B 2 O 3 , 0-25% Li 2 O, 0-25% Na 2 O, 0-12% BaO and 0-4% TiO 2 . In the three glass examples cited therein, the total amount of ZnO (combined from sources of ZnSO 4 and ZnO) is far below that required in the present inventive compositions; the highest ZnO cited is 18.5%. Even if the zinc oxide level claimed therein is raised enough to fall within the present inventive glasses, the required ranges of the Meyers patent will produce either a glass too high in sulfate to exhibit good durability, or too low in alkali to result in a glass with a low enough glass transition temperature. Thus, the glasses, both the examples cited and any other glass within the claimed range of the patent, exhibit either extremely poor durability or too high a transition temperature when compared to the instant inventive glasses. This being the case, these glasses are rendered useless in the applications envisioned for the present glasses; that of a component for use in glass/polymer alloys and composites. Furthermore, the inventive glasses, when expressed in the composition form used in the Meyers reference, fall outside the claimed composition range disclosed therein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Table I records a number of glass compositions, expressed in terms of mole percent on the oxide basis, operable in the present invention. Table IA reports the same compositions, but wherein the values of the individual components have been converted to weight percent. In addition to reporting the relative amounts of the batch constituents, Table I reports the transition temperature (T g ) in terms of °C., as measured by employing standard differential scanning calorimetry techniques, the dissolution rate expressed in terms of percentage weight loss (% wt loss) of a tab of approximate dimensions of about 1"×11/2"×3/8" (21/2 cm×4 cm×1 cm) and the working temperature (pull temp.). In addition, the appearance of the glass after formation is reported in Table I (Glass appear.); the quality and appearance of the glass formed ranged from clear (cl.) to slightly hazy (hazy). The actual batch ingredients for the glasses can comprise any materials, either the oxides or other compounds, which, upon being melted together, will be converted into the desired oxides in the proper proportions. For example ZnSO 4 .7H 2 O is conveniently employed as the source of SO 3 as well as a partial source of ZnO.
The batch materials were compounded, automatically tumble-mixed in order to secure a homogeneous melt, and placed into silica crucibles. The glass batch was then melted and maintained at temperatures ranging from 800° to 1000° for times of about three hours. Very little volatilization of P 2 O 5 , SO 3 or other species was noted below about 850° C. Table I reports that the analyzed values of SO 3 (A-SO 3 ) were typically about equal to that calculated from the batch (B-SO 3 ); values reported in weight percent. The melt was then poured into a steel mold to produce a rectangular slab having dimensions of about 4"×8"×3/8" (10 cm×20×1 cm) and that slab subsequently annealed overnight at temperature of about 250° to 275° C.
Rectangular tab-shaped pieces weighing approximately 40 grams were cut from the slab, heated to tempertures within the range of 350° to 450° C., and glass cane was hand drawn to obtain a close approximation of the working temperature. This value, for glass Examples 1-14, is reported in Table I as the "Pull temp.".
Samples were cut from the glass slab for testing the moisture resistance/durability thereof. The test involved weighing each sample carefully and then immersing the sample into a bath of boiling water. After a residence time of six hours, the sample was removed from the bath, dried in the ambient environment, and thereafter reweighed to determine any loss of weight by the sample. This loss of weight, i.e., the dissolution rate, for each glass sample is reported in Table I (Dissol. rate) and is calculated as a percentage of the original untested/unimmersed weight.
TABLE I__________________________________________________________________________ 1 2 3 4 5 6 7 8 9 10 11 12__________________________________________________________________________P.sub.2 O.sub.5 26.0 22.7 19.5 24.3 26.4 24.8 23.1 26.4 25.0 25.0 30.0 23.0SO.sub.3 10.0 15.0 20.0 15.7 10.0 12.5 15.0 15.0 15.0 15.0 12.5 12.5Al.sub.2 O.sub.3 1.6 1.4 1.2 1.4 1.6 1.5 1.4 1.6 -- -- 2.0 1.5Li.sub.2 O 6.4 5.6 4.8 5.8 5.6 5.3 4.9 5.6 -- -- 5.0 5.5Na.sub.2 O 9.7 9.5 9.3 9.0 8.0 8.0 8.0 8.0 -- -- 8.0 8.0K.sub.2 O 6.4 6.7 6.9 6.0 5.7 5.8 6.0 5.7 -- -- 4.0 5.5ZnO 38.1 36.9 35.7 35.9 41.6 40.7 39.9 40.7 45.0 40.0 38.5 42.5CaO 1.3 1.5 1.6 1.3 0.6 0.7 1.0 0.6 -- -- -- 0.75SrO 0.6 0.8 1.1 0.5 0.6 0.7 1.0 0.6 -- -- -- 0.75ZnCl.sub.2 -- -- -- -- -- -- -- -- 15.0 20.0 -- --Melt. temp. (°C.) 800 800 800 800 800 800 800 800 -- 1000 850 825Glass Appear. cl. hazy cl. hazy cl. cl. cl. cl./hazy cl. cl. cl. cl.T.sub.g (°C.) -- -- -- 288 286 276 283 -- -- -- --Pull (°C.) 385 -- 375 380 400 385 375 390 -- -- 400 405Dissolution Rate 0.02 0 0.15 0.03 0 0 0.12 0.0 -- -- 0.0 0.02(% wt. loss)A - SO.sub.3 8.7 13.4 18.0 13.4 -- -- --B - SO.sub.3 8.6 13.2 17.9 12.9 -- -- --__________________________________________________________________________
TABLE IA__________________________________________________________________________1 2 3 4 5 6 7 8 9 10 11 12__________________________________________________________________________P.sub.2 O.sub.5 39.8 33.3 30.9 37.5 39.9 37.8 35.6 38.3 34.0 33.1 44.3 35.6SO.sub.3 8.6 13.2 17.9 13.7 8.5 10.7 13.0 12.2 11.5 11.2 10.4 10.9Al.sub.2 O.sub.3 1.7 1.5 1.3 1.6 1.7 1.6 1.5 1.6 -- -- 2.1 1.6Li.sub.2 O 2.0 1.9 1.6 1.9 1.8 1.7 1.6 1.7 -- -- 1.6 1.7Na.sub.2 O 6.5 6.5 6.5 6.1 5.3 5.4 5.4 5.1 -- -- 5.2 5.4K.sub.2 O 6.5 6.9 7.3 6.1 5.7 5.9 6.2 5.5 -- -- 4.0 5.7ZnO 33.4 32.9 32.4 31.8 36.1 35.6 35.3 34.6 35.0 30.3 32.5 37.7CaO 0.8 0.9 1.0 0.8 0.3 0.4 0.4 0.3 -- -- -- 0.4SrO 0.6 0.9 1.2 0.6 0.6 0.8 0.9 0.6 -- -- -- 0.9ZnCl.sub.2 -- -- -- -- -- -- -- -- 19.5 25.4 -- --__________________________________________________________________________
Whereas the above description reflects laboratory melting and forming practice only, it will be appreciated that the recited compositions are capable of being melted in large scale melting units and shaped into desired configurations utilizing forming techniques conventional in the glassmaking art. As is the case with standard glassmaking practice, it is only necessary to ensure that the batch materials are mixed together thoroughly and then melted at temperatures which will ensure a homogenous melt without excessive volatilization of sulfide oxides, chloride and fluoride, and that the melt is thereafter cooled and shaped into a glass body of a desired geometry which is customarily annealed.
These inventive glasses possessing transition temperatures normally below about 300° C. and working temperatures of 350° and above, exhibit measures of durability/resistance to moisture ranging from 0.0 to 0.15 percent weight loss when immersed in boiling water for six (6) hours. These weight loss values are exceptionally low for glasses with transition/working temperatures in the range which these inventive glasses exhibit; they are comparable to those measures of durability exhibited by glasses possessing transition/working temperatures as much as 100° C. greater, e.g., those phosphate glasses disclosed in U.S. Pat. No. 4,940,677 (Beall et al.)
Based upon an overall balance of physical and chemical properties, Example 6 is the most preferred embodiment of the inventive glasses.
Table II reports the composition of three typical metaphosphate glasses, exhibiting transition temperatures comparable to those exhibited by the inventive glasses. It is clear from the durability data reported therein (only a 1 hour immersion in boiling water), ranging from a 5% weight loss to a complete dissolving of the glass, that the inventive glasses exhibit a much greater durability than these metaphosphate samples possessing comparable transition temperatures.
TABLE II______________________________________ 13 14 15______________________________________P.sub.2 O.sub.5 46 46 46Al.sub.2 O.sub.3 4 4 4Li.sub.2 O 25 -- 25Na.sub.2 O 25 25 --K.sub.2 O -- 25 25Dissolution Rate 5.0 dissolved 25(% wt. loss) (100%)T.sub.g (°C.) 290 260 280______________________________________
Table III reports the composition of Examples 1-12 in the form as is used in the earlier-described Meyers reference. In converting the instant examples to this form, it was assumed that first source of the SO 3 was K 2 SO 4 ; if any SO 3 was still needed it was then assumed that it was supplied through the addition of Na 2 SO 4 ; and finally if an amount of SO 3 was still required it was assumed that its source was ZnSO 4 . This order of preference for designating the sulfate in terms of K 2 SO 4 , Na 2 SO 4 , and ZnSO 4 , is clear from Examples 1 and 2 of the Meyers patent. In Example 1, all of the alkali, K 2 O and Na 2 O, is listed in terms of sulfates. The zinc by comparison, is listed as both ZnSO 4 and ZnO. In other words, zinc is designated as sulfate up to the total sulfate level desired by the patentee, and the rest of the zinc is listed as the oxide. This could just as easily been accomplished by using all ZnSO 4 and listing part of the Na or K as oxides, but the patentee evidently preferred to list the alkali ahead of zinc as sulfates. Similarly, from Example 2, all the potassium is listed as K 2 SO 4 , while both soda and zinc are split between oxides and sulfates. While any arrangement can obviously be used, the patentee prefers K, Na, and Zn as the order of preference in describing his compositions. We have used the same format (order of preference) in Table III.
It is clear from the compositions listed in this table that the inventive glasses are compositionally very distinct from those disclosed in the Meyers et al. reference.
TABLE III__________________________________________________________________________1 2 3 4 5 6 7 8 9 10 11 12__________________________________________________________________________K.sub.2 SO.sub.47.1 7.9 8.7 7.1 6.3 6.6 6.7 6.4 -- -- 4.6 6.3Zn.sub.2 SO.sub.4-- -- 4.7 0.8 -- -- 1.1 1.3 17.6 17.6 0.6 --Na.sub.2 SO.sub.44.0 9.8 11.7 10.7 4.8 7.6 8.9 9.0 -- -- 9.2 8.0P.sub.2 O.sub.528.9 26.7 24.0 28.9 29.3 28.3 25.7 29.6 29.4 29.4 34.3 26.3ZnO 42.3 43.4 40.1 41.8 46.2 46.5 48.3 44.2 35.3 29.4 43.4 48.6Li.sub.2 O7.1 6.6 6.0 6.9 6.2 6.1 5.5 6.3 -- -- 5.7 6.3Na.sub.2 O6.8 1.4 -- -- 4.1 1.5 -- -- -- -- -- --CaO 1.4 1.8 2.0 1.5 0.7 0.8 1.1 0.7 -- -- -- 0.9SrO 0.7 0.9 1.4 0.6 0.7 0.8 1.1 0.7 -- -- -- 0.9ZnCl.sub.2-- -- -- -- -- -- -- -- 17.6 23.5 -- --Al.sub.2 O.sub.31.8 1.6 1.5 1.7 1.8 1.7 1.6 1.8 -- -- 2.3 1.7__________________________________________________________________________
Table IV reports a number of glass compositions expressed in terms of mole percent on the oxide basis which are outside the scope of the instant invention, but within the composition range disclosed in the earlier-described Meyers reference. In addition to the composition breakdown and the dissolution rate of the glass, the table reports the melting temperature (Melt. temp.) and the glass appearance, before and after the immersion in the boiling water. The glass, before immersion, ranges in appearance and quality from a clear stable glass (cl.) to a translucent hygroscopic glass (transl./hygro). Table V reports the same compositions though reported in the composition form used in the Meyers patent. These comparison glass examples, 16 to 22 were, except for changing the respective components as shown in Table II, made in the same way as that earlier disclosed for inventive glass Examples 1-12. Note, however, that Example 20 (reported as unmelted) would not melt, thus no glass was formed; this composition would not melt to form a glass even when the melting instructions detailed in the Meyers reference were adhered to.
It is quickly evident that, with the exception of Example 21, these glasses exhibit poor durability measures; either high dissolution rates or hygroscopic behavior. In fact, this durability is poor enough to effectively render these glasses useless for any application envisioned for the inventive glasses. It is important to note that these weight loss percentages are values for various immersion times; Ex. 16 and 17-21/2 hrs., Ex. 19-2 hrs, and Ex. 18 and 20-23-6 hrs. As reported in Table II, the examples exhibited weight losses as a result of boiling water immersion ranging from a 0.3% weight loss in 6 hours, to those which either dissolved (dissol.) or were converted into a unconsolidated white residue (unconsol. white res.) or possessed surface spalling (sur. spall.)
Examples 16-18 are specific examples disclosed in the Meyers patent as possessing low hydroscopic behavior; however, the durability values measured show that none of these compositions exhibit or approach the durability as exhibited by the inventive composition. Examples 19 through 23 were various composition attempts in order to identify a glass composition within this reference which would exhibit durability on the order of the inventive sulfophosphate composition's durability. For example, comparison examples 21 and 22 possesses the maximum amount of Zn (highest ZnSO 4 and ZnO allowable) and the lowest amount of P 2 O 5 allowable within the claimed composition range; neither exhibit durability numbers as low as desired. Example 21, while approaching the low dissolution rates of the current invention, is nevertheless far too high in transition temperature (>350° C.) and working temperature (>450° C.) to be useful in the current invention. Simply put, none of the comparison examples, and likely no composition falling within the Meyers reference composition range possesses the requisite high ZnO and sufficiently low SO 3 in order to ensure a glass which possesses a T g of about 300° C. with a corresponding excellent resistance to moisture.
TABLE IV__________________________________________________________________________ 16 17 18 19 20 21 22 23__________________________________________________________________________P.sub.2 O.sub.5 26.4 22.7 45.6 56 19 21.5 12.2 26.2SO.sub.3 28.0 38.8 17.4 16 16 30.5 35.9 18.0K.sub.2 O 7.0 5.9 4.4 4 4 2.8 6.4 3.3Na.sub.2 O 7.0 17.1 4.4 7 29 2.8 6.5 14.8Li.sub.2 O 13.2 -- 6.5 -- 15 -- -- 5.7ZnO 18.4 15.7 8.7 33 33 42.4 39.1 32.0B.sub.2 O.sub.3 -- -- 3.2 -- -- -- -- --BaO -- -- 9.7 -- -- -- -- --Melt. temp. (°C.) 600-700 600-700 600-750 600-750 unmelted 875 800 800Glass appear. cl. cl. transl./hygro. cl./hygro. -- cl. cl. cl.T.sub.g (°C.) 233 249 264 243 -- >350 --Pull (°C.) -- >450 375 375Dissolution rate 40 80 0.2 51 51 0.2 100 1.0(% wt. loss)Appearance unconsol. unconsol. hazy glass dissol. unmelted -- unconsol. sur.after boil white res. white res. white spall. res.__________________________________________________________________________
TABLE V______________________________________16 17 18 19 20 21 22 23______________________________________K.sub.2 SO.sub.4 9.7 9.7 5.3 4.0 4.0 4.0 10.0 4.0Zn.sub.2 SO.sub.4 19.5 25.6 10.6 8.0 8.0 36.0 36.0 14.0Na.sub.2 SO.sub.4 9.7 28.0 5.3 4.0 4.0 4.0 10.0 4.0P.sub.2 O.sub.5 36.7 36.7 55.3 56.0 19.0 31.0 19.0 32.0ZnO 6.1 -- -- 25.0 25.0 25.0 25.0 25.0Li.sub.2 O 18.3 -- 7.9 -- 15.0 -- -- 7.0Na.sub.2 O -- -- -- 3.0 25.0 -- -- 14.0BaO -- -- 11.8 -- -- -- -- --B.sub.2 O.sub.3 -- -- 3.9 -- -- -- -- --______________________________________ | This invention relates to the preparation of a glass exhibiting a transition temperature normally below about 300°, a working temperature below about 400°, while, at the same time, exhibiting excellent resistance to attack by water. Specifically, the present invention discloses a glass consisting essentially in terms of mole percent on the oxide basis, of 15-35% P 2 O 5 , 1-25% SO 3 , 30-55% ZnO, 0-25% R 2 O, wherein R 2 O is selected from the group consisting of 0-25% Li 2 O, 0-25% Na 2 O, and 0-25% K 2 O, and up to a total of 15% of optional ingredients in the indicated proportions selected from the group consisting of 0-10% Al 2 O 3 , 0-10% MgO, 0-10% CaO, 0-10% SrO, 0-10% BaO, 0-10% MnO, 0-10% transition metal oxides and 0-15% Cl+F, as analyzed in weight percent. | 2 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a washer-dryer with a temperature sensor and a preferred method for its operation. The invention relates in particular to a washer-dryer including a tub, a drum mounted in the tub to be rotatable around an essentially horizontal axis for receiving laundry items, a process air circuit comprising an air heater and a blower to heat and circulate the heated air through the drum, a heat exchanger to condense moisture from the process air exiting the drum, and a temperature sensor, as well as a preferred method for its operation.
[0002] Drum washing machines are popular, due to their water saving ability and avoidance of damage to the laundry processed thereby. In the past, washer-dryers, i.e., drum washing machines with drying functions, have acquired a considerable market share. Washer-dryers are popular because they combine in a compact manner the functions of a washing machine and a dryer. Moreover, a washer-dryer is already provided with a water supply access, such that water can be used not only for washing laundry, but also for further treatment steps. When drying, a such a drum washer-dryer usually takes in air through a fan set on an outside of a tub containing the drum, heats the air with an air heater, and then transfers the heated air to the tub and the inside of the drum. There, the heated air exchanges heat with the water contained in the laundry and takes moisture from the wet laundry. The moisture is then condensed in a condensing unit mounted on an outer side of the tub, and the condensate thus formed drained out of the washing machine.
[0003] In general, washing machines with drying functions dry the laundry at substantially constant temperatures and in preset periods of time. Such a method may however result, on one hand, overdrying the laundry when the amount of laundry to be dried is too small and, on the other hand, underdrying the laundry when the amount of laundry is too large. To overcome these unwanted results, temperature sensors and/or humidity sensors disposed inside the machine may be used to detect the temperature and/or humidity. The degree of dryness can then be determined based on the sensor signals and, as a result, a drying process can be controlled with relative accuracy.
[0004] As an example, document GB 2 082 742 A discloses a dryer which controls the drying time according to the internal temperature change rate in combination with a consideration of the type of clothes being washed and predetermined degree of dryness.
[0005] Document CN 1 503 864 A discloses a control unit for detecting the dryness in an air exhaust dryer based on the signals detected by a humidity detection unit and a temperature detection unit. The drying process can thereby be controlled.
[0006] Document CN 1 746 379 A discloses a drum washing machine with a drying function which has an upper temperature sensor and a lower temperature sensor mounted respectively on an upper end and a lower end of a vertical part of a hot air circulating pipe, and which has a control unit that determines a degree of dryness reached, based on the temperature difference detected between the upper and lower temperature sensors, and thereby controls the drying process.
[0007] Document CN 1 611 659 A discloses a drum washing machine system control device, which determines the load of the laundry to be dried according to data obtained by a humidity sensor set on a condensing pipe, and a drying device for drum washing machines which adjusts the temperature of a heater based on a laundry load, and a control method therefor.
[0008] Document WO 2007/138019 A1 discloses a drum washing machine with a drying program and a control method therefor. The washing machine comprises a tub to hold water; a drum rotatable set in the tub; a heating drying tunnel configured outside said tub; a first temperature detection unit set in the said tub; and a system control unit which controls the drying program based on the signal fed back from the first temperature detection unit.
[0009] Documents WO 2009/130145 A1 and US 2011/0030239 A1 each disclose a household appliance for drying a laundry item, the household appliance comprising a treatment chamber to receive the laundry item; a closed process air circuit to feed process air through the treatment chamber, the closed process air circuit comprising inter alia: a blower to move the process air; a condenser to condense out moisture carried in the process air; a heater to heat the process air; a first measurement device to determine a temperature of the process air when the process air enters the treatment chamber to provide a first measurement signal; and a controller to control the blower and the heater as a function of the first measurement signal. According to the only Figure, a number of temperature sensors on the process air duct or the cooling air duct can be used to control the drying process with redundancy and thus with a particularly high level of stability.
[0010] The cleaning of a temperature sensor from fluff, also called “lint”, and inorganic deposits poses a serious problem in that an agglomeration of fluff and inorganic deposits which might even result in limestone may interfere with the proper functioning of the washer-dryer. It has hence been known to clean this temperature sensor, including an NTC (Negative Temperature Coefficient) sensor, by means of a special rinsing process. This rinsing process consumes however up to about 6 liters (about 1.6 US gal.) of water. Such excessive water consumption should be avoided for economic and ecologic reasons.
[0011] Moreover, the presence of water on the sensor may cause faulty temperature indications. However, if an accurate temperature indication of the hot and humid process air is not obtained, proper functioning of the washer-dryer in a drying phase may not be assured.
[0012] Fluff accumulation and inorganic deposit formation is important in washer-dryers with an air-air heat exchanger, since much fluff usually accumulates on the heat exchanger. As regards the temperature sensor, this fluff will also disturb the correct temperature measurement of the temperature of the process air and thus the proper functioning of the washer-dryer. Fluff accumulation will be exacerbated if water is present on the surface of the temperature sensor. Another problem that might disturb the proper functioning of the sensor and thus a safe and reliable drying phase is due to the fact that sometimes water drops are splashed against the temperature sensor, causing a wrong temperature measurement. Finally, water evaporation at the surface of the temperature sensor can contribute to the formation of inorganic deposits.
[0013] The present use of temperature sensors and their respective cleaning processes do not ensure a proper cleaning of the temperature sensors, especially over a long service life.
SUMMARY OF THE INVENTION
[0014] It is accordingly an object of the present invention to provide a washer-dryer with a temperature sensor that is less effected by the presence of water, inorganic substances and/or fluff and thus enhances reliable and safe operation of the washer-dryer especially during the drying phase, and of a corresponding method for its operation.
[0015] In accordance with the present invention, this object is achieved by a washer-dryer and a method for its operation with the features of the respective independent claims. Preferred embodiments of the invention are detailed in dependent claims. Preferred embodiments of the washer-dryer correspond to preferred embodiments of the method, even if they are not explained herein in detail.
[0016] The invention thus relates to a washer-dryer having a tub, a drum mounted in the tub to be rotatable around an essentially horizontal axis for receiving laundry items, a process air circuit comprising an air heater and a blower to heat and circulate the heated air through the drum, and a heat exchanger to condense moisture from the process air exiting the drum. The washer-dryer includes at least one temperature sensor having a surface formed at least partially from a hydrophobic material.
[0017] The hydrophobic material is not particularly limited as long as it will repel water while retaining a sufficient heat transfer capability to assure proper functioning of the sensor.
[0018] In a preferred embodiment of the washer-dryer, the temperature sensor has an elongate body and a temperature sensitive tip. More preferably, at least one of the the elongate body and the temperature sensitive tip includes a hydrophobic surface layer containing the hydrophobic material and/or a nanomaterial wherein nanoparticles render the surface hydrophobic.
[0019] In a further preferred embodiment, the elongate body is made of a hydrophobic polymer material, for example a fluorine containing polymer and/or a nanomaterial wherein nanoparticles render the surface hydrophobic.
[0020] “Elongate body” as used herein may also be termed “housing”.
[0021] Preferably, the hydrophobic material contains or consists of fluorine containing organic polymer. More preferably, the fluorine containing organic polymer is selected from the group consisting of polyvinylfluoride, polyvinylidene fluoride, po tetrafluoroethylene, polychlorotrifluoroethylene, perfluoroalkoxy polymer, fluorinated ethylene-propylen copolymers, po ethylenetetrafluoroethylene, po ethylenechlorotrifluoroethylene, perfluoropolyesther, perfluoropolyoxetane, and any mixture thereof.
[0022] In the fluorine containing organic polymer, the fluorine content is preferably higher than about 30 weight %, and more preferably higher than about 50 weight %, based on the weight of the fluorine containing organic polymer.
[0023] One example is a fluoroelastomer copolymer based on hexafluoropropylene and vinylidenefluoride which is available under the trade name TECNOFLON® from Solvay Solexis.
[0024] The hydrophobic material, in particular a fluorine containing polymer, can be applied to the sensor by coating a surface of the sensor with a highly hydrophobic paint or by applying a shrinking hose or cover made of the hydrophobic material. Furthermore, the sensor housing, which is usually stainless steel, can be formed from a hydrophobic plastic material, preferably a hydrophobic plastic material containing a fluorine containing polymer.
[0025] In a preferred embodiment of the washer-dryer, the temperature sensor is located in a connecting part extending between the tub and the heat exchanger. Here it is more preferable that the connecting part is a flexible hose connecting the tub with the heat exchanger. Preferably, the temperature sensor is situated in a lower half of the connecting part.
[0026] In the washer-dryer of the present invention, the temperature sensor is preferably an NTC temperature sensor. NTC temperature sensors are preferred since they allow enhancing the accuracy of the temperature determination.
[0027] The washer-dryer may include two or more temperature sensors to improve its operation. Preferably, the washer-dryer of the present invention includes at least one temperature sensor located in the connecting part between the tub and the heat exchanger (which also may be referred to in the following as “first temperature sensor”). More preferably, the washer-dryer also includes a second temperature sensor which may be placed in the process air circuit at a location in front of an entrance into the interior of the drum, for example between the air heater and the sleeve.
[0028] In a preferred embodiment of the washer-dryer, the first temperature sensor is immersible in the aqueous liquid when the washer-dryer is operated in at least one of a washing phase and a rinsing phase.
[0029] Accordingly, fluff and deposits of inorganic salts from a previous drying phase can be removed in a washing or rinsing phase preceding the next drying phase. Thus, the formation of fluff agglomerates or limestone might be avoided. As a result, the first temperature sensor can function properly and the washer-dryer of the present invention can also function properly.
[0030] The connecting part between the tub and the heat exchanger which is usually present in the washer-dryer of the present invention can be a part which is integrally formed into the body of the heat exchanger or the tub. Alternatively, it can be formed as a separate piece which is placed between the tub and the heat exchanger. In a particular preferred embodiment, the connecting part is a flexible hose connecting the tub with the heat exchanger.
[0031] The first temperature sensor may in principle be situated at various locations within the connecting part. It is preferred that the first temperature sensor is located in a lower portion of the connecting part. “Location in a lower portion” means here in particular that a tip of the first temperature sensor is at least partially, preferably totally located in the lower half of the connecting part.
[0032] In this embodiment, cleaning the first temperature sensor in a washing or rinsing phase can be achieved with a lower level of the aqueous liquid in the tub, the connecting part, or both. The location in the lower half of the connecting part allows placing the connecting part higher than in the case where the first temperature sensor is placed in the upper half of the connecting part without negatively affecting the cleaning process.
[0033] It is moreover preferred that the temperature sensor in particular the first temperature sensor, is inclined toward the tub. For example, if the temperature is located in an essentially horizontal connecting part between the tub and the heat exchanger, “inclined toward the tub” means that a tip of the sensor is closer to the tub than a body of the sensor.
[0034] This allows improved cleaning of the temperature sensor. For example, an inclination of the NTC toward the air flow assists movement of water drops on the NTC surface from its top to the bottom. The effect is more pronounced when the first temperature sensor is inclined toward the tub by an angle α in the range of from about 5° to about 30°, more preferably in the range of from about 10° to about 25°, relative to a vertical axis. “Vertical axis” as used herein usually refers to an axis that is perpendicular to a ground plate of the washer-dryer, the ground level of the room where the washer-dryer is to be placed, or both.
[0035] Preferably, in the washer-dryer of the present invention, the first temperature sensor forms an angle β less than about 60° with a horizontal plane through the center of the connecting part. The horizontal plane is in general perpendicular to the vertical axis mentioned above.
[0036] The connecting part comprises preferably several folds and the first temperature sensor is preferably placed in or on one of these folds. Preferably, the connecting part is formed from flexible plastic material.
[0037] The washer-dryer of the present invention includes a heat exchanger. In principle, a heat exchanger might be realized by using relatively cold water from the water supply or another source to condense the moisture carried by the process air in a washer-dryer. This embodiment can be realized fairly easily, but uses a generally excessive amount of water and is thus preferably avoided.
[0038] It is preferred according to the present invention to us an indirectly cooled condenser, in which there is no direct contact between the warm and humid process air to be cooled and the cooling agent used. An indirectly cooled condenser can be realized for example as an air-cooled condenser, i.e. an air-air heat exchanger, with the air serving as the cooling agent being taken usually from the room wherein the washer-dryer is placed. The used air is usually fed back to this room again after it has been used in the cooling step.
[0039] The indirectly cooled condenser may be also embodied as a heat sink of a heat pump in the washer-dryer. The heat pump takes in heat from the hot and humid process air in the condenser, pumps this heat to the air heater in the process air circuit and discharges it back to the process air. Such a heat pump can be embodied as a compressor heat pump, in which a cooling agent circulates which is cyclically evaporated in the condenser as it absorbs heat from the air flow and is condensed in the condenser as it emits heat to the air flow. The heat pump may also be operable by means of a reversible sorption process, a regenerative gas circuit process or the Peltier effect.
[0040] In a particularly preferred embodiment of the present invention, the heat-exchanger is an air-to-air heat exchanger, also called an air-air heat exchanger.
[0041] In still a further preferred embodiment of the present washer-dryer, the first temperature sensor is closer to the tub than to the heat exchanger. This allows the first temperature sensor, for example an NTC temperature sensor to be assembled close to vibrations generated as a result of the washing and spinning processes which provide forces hindering any adhesion at the temperature sensor surface and can assist the removal of water drops.
[0042] Preferably, the temperature sensor is placed in the process air circuit, for example the connecting part, in a manner whereby it can measure the temperature in or close to the center of the process air flow. This allows a more accurate control of the drying phase. Thus, the temperature sensor is preferably arranged such that it may be in contact with the center of the process air flow. In addition, the process air circuit, for example the connecting part between tub and heat exchanger, may be provided with a guiding arrangement that guides the process air flow towards the temperature sensor.
[0043] In general, a washer-dryer is connected to a water supply system which provides to guide water through a detergent rinsing shell such that portions of detergent or auxiliaries can be flushed into the tub. Such a water supply system might involve a bifurcation of the heat exchanger such that water from the water supply system might be used for the rinsing device of the heat exchanger and/or as cooling liquid itself in the heat exchanger.
[0044] In the case of an indirectly cooled condenser, the washer-dryer of the present invention can thus contain a rinsing device for the condenser, which cleans the heat exchanger. In such an embodiment, the rinsing device can be used to additionally clean the temperature sensor. To this end the rinsing device might be connected to the aforementioned water supply. Water may be used as an aqueous cleaning fluid. In that case it might be useful to use the water from the water supply. Ingredients may be supplied to the cleaning water that assist in the cleaning process. In a preferred process according to the present invention, the aqueous cleaning fluid contains ingredients that allow dissolving inorganic deposits on the sensor. A useful ingredient may be an acid that assists in dissolving calcium carbonate.
[0045] In general, a washer-dryer may include a suds discharge system at its base including a drain valve and a suds pump and any necessary piping. Furthermore, a washer-dryer in general contains laundry agitators and/or scooping devices. A plurality of such laundry agitators and/or scooping devices, in particular, three or four such devices, is preferred. The laundry agitator may be cast into the drum as an integral component or inserted into the drum as an additional component. Such a structure configuration is representative of a plurality of embodiments, which may include an arrangement of particular fins or be formed as a helical wound configuration of an interior part of the drum.
[0046] A washer-dryer generally has a switching arrangement for rotating and stopping the drum. Moreover, a washer-dryer according to the present invention preferably includes a sensor for determining a quantity of liquid disposed in the suds container. The sensor is usually placed in a lower part of the tub. A conventional sensor for determining the water level can be used as a sensor for determining the quantity of liquid disposed in the tub, i.e. the suds container, the sensor signal of which is tracked during machine operation. Such a sensor generally measures a hydrostatic pressure p and/or a temporal gradient (Δp/Δt) 1 of the hydrostatic pressure p.
[0047] In addition, a washer-dryer in general contains a heater for the direct heating of an aqueous liquid, for example suds. This heater, termed herein “water heater”, is in general disposed in the tub below the drum.
[0048] The invention is moreover directed to a method for operating a washer-dryer having a tub, a drum mounted in the tub to be rotatable around an essentially horizontal axis for receiving laundry items, a process air circuit comprising an air heater and a blower to heat and circulate the heated air through the drum, a heat exchanger to condense moisture from the process air coming out of the drum. The method includes the steps of evaluating temperature signals measured by a temperature sensor wherein at least a part of a surface of the temperature sensor contains a hydrophobic material; and controlling a drying phase by evaluating temperature signals measured by the temperature sensor. In this process the temperature sensor is preferably placed in between the tub and the heat exchanger.
[0049] In a preferred method of the present invention, the temperature sensor, preferably a first temperature sensor, is cleaned by an aqueous liquid coming from the tub, a rinsing device, or both. Preferably, this method is conducted under forced convection to increase a flow around the first temperature sensor. Forced convection that results in an increased turbulent flow around the first temperature sensor can be established by a specific rotation pattern of the drum such that the aqueous liquid in the tub is pushed toward, preferably back and forth in relation to, the first temperature sensor in the connecting part. As an alternative or in addition thereto the blower of the washer-dryer may be used to create a strong air flow which is directed to on the aqueous liquid and thus creates forced convection.
[0050] A specific cleaning phase can be defined within a washing or rinsing phase that is optimized to clean the first temperature sensor.
[0051] Cleaning can be preferably carried out in a wash or rinse phase where an imbalance in the load distribution gives rise to vibrations of the drum and the tub, respectively. This assists in the removal of fluff or inorganic deposits.
[0052] In a preferred process of the present invention, a drying phase is conducted by controlling the blower and the air heater such that a set maximum temperature T max for the temperature of the warm air is not exceeded. In a preferred method of the present invention, the drum is rotated during the flushing phase to cause the sensor to vibrate. In this embodiment it is preferred that a connecting part between the tub and the heat exchanger is sufficient rigid to allow the transmission of vibrations of the tub. Moreover, the transmission of vibrations is more pronounced when the sensor is closer to the tub than to the heat exchanger. This allows the first temperature sensor, for example an NTC temperature sensor, to be assembled close to the moving oscillation system vibrations from the rotating drum which provide forces hindering any adhesion at the sensor surface and can assist the removal of water drops, fluff and inorganic deposits.
[0053] The invention has several advantages. The washer-dryer of the present invention is configured for operation with a temperature sensor that is resistant to water drops and fluff. The evaporation of water drops at the sensor surface, in particular at the surface of an NTC temperature sensor will be avoided. The temperature sensor can be easily cleaned from deposits of fluff or inorganic salts, for example during a washing and rinsing phase of the washer-dryer or by a separate cleaning process. Thus, in the washer-dryer of the present invention, the temperature sensor is configured to provide highly reliable signals regarding the temperature of the process air leaving the drum and the tub. As a result, the operation of the washer-dryer can be controlled more precisely. The risk of overheating the laundry items to be dried can be avoided. This is of particular advantage when sensitive laundry items such as wool, silk or lace are being dried.
[0054] Fluff accumulated on the first temperature sensor can be removed efficiently in a washing or rinsing process preceding the drying phase. Thus, for controlling the drying phase a freshly cleaned first temperature sensor can be used. As a result, the washer-dryer of the present invention allows precise and safe drying phases. These advantages can be achieved in embodiments of the invention without an increased water level and without additional water consumption. The washer-dryer can thus be operated in embodiments not only safely, but also without the need of using undesirable amounts of water.
BRIEF DESCRIPTION OF THE DRAWINGS
[0055] FIG. 1 is a diagrammatic view of a temperature sensor according to a preferred embodiment of the present invention.
[0056] FIG. 2 is a diagrammatic view of a washer-dryer according to a first preferred embodiment of the present invention.
[0057] FIG. 3 is an side, partial cutaway view of a connecting part between the tub and the heat exchanger in a washer-dryer according to the present invention.
[0058] FIG. 4 is a diagrammatic view of a washer-dryer according to a second preferred embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0059] Turning now to the drawings and, more particularly to FIG. 1 , a temperature sensor according to one embodiment of the present invention configured for carrying out the method of the present invention is illustrated. Other embodiments are conceivable.
[0060] With continued reference to FIG. 1 , the temperature sensor 14 has an elongate body 30 that is covered by an hydrophobic layer 35 which includes a fluorine containing organic polymer. In this embodiment, a temperature sensitive tip 31 of sensor 14 is not covered with a hydrophobic layer. However, other embodiments are possible as long as the temperature sensor 14 can measure the temperature with sufficient accuracy.
[0061] FIG. 2 shows a washer-dryer according to a first preferred embodiment in which the method of the present invention can be implemented. Other embodiments are conceivable. The washer-dryer of this embodiment includes a tub 1 (also to be referred to as “suds container”) and a drum 2 which is placed in the tub 1 such that it can be rotated around an essentially horizontal axis 3 . Laundry items 16 are placed in the drum 2 for treatment. The tub 1 is connected by means of a flexible hose 25 as a connecting part to a heat exchanger 8 which is herein an air-air heat exchanger.
[0062] The tub 1 is connected to a pump 12 via a suds draining duct 19 which facilitates the discharge of an aqueous liquid 11 , for example suds, from the tub 1 . A waste water conduit 13 directs the aqueous liquid 11 out of the washer-dryer. The drum 2 is driven by a drive motor 4 .
[0063] The drum 2 is filled through a door 22 which allows the access to the interior of the drum 2 with laundry 16 to be treated. In order to wash laundry 16 in the washer-dryer, the washer-dryer is connected to a water feed line 20 . The water feed line 20 is connected to a detergent rinsing shell 21 from which detergent and auxiliary agents can be flushed into the tub 1 with the aid of water from the water feed line 20 to allow a washing process in the washer-dryer. In this embodiment, this is achieved through a part of the process air circuit 5 and a sleeve 23 .
[0064] For drying wet laundry items in the drum 2 of the washer-dryer illustrated in FIG. 2 , which operates according to the principle of circulating air, air heated by an air heater 7 (“process air”) is driven through the process air circuit 5 with the aid of a blower 6 . Heated process air then enters the tub 1 and the drum 2 , respectively, through the sleeve 23 . The humid and warm process air resulting from the passage of the process air through the drum 2 , where it has taken up moisture from the wet laundry items 16 , arrives at a rear exit 24 of the tub 1 and thereafter at the heat exchanger 8 . In the air-air heat exchanger 8 , the process air is cooled with cold air and moisture contained in the process air condenses. The condensate may be collected in a condensate container (not shown) or may flow back to the tub 1 and finally to the suds draining duct 19 whereby it can be discharged through the waste water conduit 13 . The dried air flows inside the process air circuit 5 , is heated again by the air heater 7 and then introduced again via the sleeve 23 into the drum 2 . Filled arrows 17 indicate the flow of the warm air. Short, unfilled and unnumbered arrows indicate the flow of the cooling air inside the air-air heat exchanger 8 .
[0065] A sensor 14 is placed between the tub 1 and the air-air heat exchanger 8 , preferably in a flexible hose 25 , and is used to control a drying phase in the washer-dryer. The sensor 14 is here a first temperature sensor 14 and more particularly an NTC-type temperature sensor.
[0066] The washer-dryer shown in FIG. 2 is configured for flushing the heat exchanger 8 with an aqueous cleaning liquid 15 . To that end, the washer-dryer of FIG. 2 has a rinsing device 10 disposed above the heat exchanger 8 . Accordingly, the rinsing device 10 is configured for flushing both the air-air heat exchanger 8 and the sensor 14 with an aqueous cleaning liquid 15 , for example, by spraying. Moreover, the rinsing device 10 in this embodiment is connected to a water supply system, for example, the water feed line 20 , via a water valve 9 . Thus, water from a water supply system can be used as the aqueous cleaning liquid 15 . The aqueous cleaning liquid 15 may contain ingredients that assist in the cleaning process. In particular, the aqueous cleaning liquid 15 may contain ingredients that assist in the removal of inorganic deposits like limestone from the sensor 14 . For example, an acid may be applied.
[0067] The use of a temperature sensor wherein at least a part of the surface of the temperature sensor is made of a hydrophobic material enhances the ability of the temperature sensor to be cleaned. Moreover, water is not retained on the sensor surface.
[0068] In order to allow a better control not only of a flushing phase, but also a drying phase in the washer-dryer, a second temperature sensor 27 is placed in the process air circuit 5 close to the door 22 .
[0069] FIG. 2 also shows a control unit 18 which controls the operation of the washer-dryer based at least partially on the signals received from the first and second temperature sensor and in particular controls of the method of the present invention. The water valve 9 , the air heater 7 and a water heater 32 are all controlled by the control unit 18 as a function of a pre-programmed workflow. The program may utilize a timer signal. Further, the program utilize signals based on sensed conditions or parameters such as the level of an aqueous liquid, for example the suds level, the suds temperature and the speed of the drum 2 .
[0070] A drying phase is usually carried out by circulating process air repeatedly through the process air circuit 5 until a desired degree of dryness in the laundry items 16 is obtained. The washer-dryer of FIG. 2 provides enhanced precision in controlling the drying phase in that the drying phase is conducted by controlling the blower 6 and the air heater 7 such that a set maximum process air temperature T max is not exceeded.
[0071] A hydrostatic pressure sensor 33 for measuring the hydrostatic pressure p in the suds container 1 is also provided.
[0072] FIG. 3 shows an enlarged view of a connecting part extending between the tub and the heat exchanger. The connecting part may be a hose. In particular, a cut through a hose is shown such that the interior of the hose can be seen.
[0073] The first temperature sensor 14 shown herein is an NTC-type temperature sensor with an elongate body 30 and a temperature sensitive tip 31 . The first temperature sensor 14 is located on a fold 35 in a lower half of the bellows-like flexible hose 25 . The first temperature sensor 14 is inclined in the direction of the tub which is not shown here. However, an arrow indicates the direction to the tub 1 . The first temperature sensor 14 is here inclined toward the tub 1 by an angle α in the range of from about 5° to about 30°, relative to a vertical axis 28 .
[0074] The elongate body 30 includes a hydrophobic surface layer 35 consisting of a fluorine containing organic polymer.
[0075] With reference to FIG. 4 , a washer-dryer according to a second embodiment of the present invention configured for carrying out the method of the present invention is illustrated. Still further embodiments are conceivable.
[0076] The washer-dryer of this embodiment includes a tub 1 and a drum 2 which is placed in the tub 1 such that it can be rotated around an essentially horizontal axis 3 . Laundry items are placed in the drum 2 for treatment. The tub 1 is connected to a heat exchanger 8 by a flexible hose 25 as connecting part. The heat exchanger 8 may be an air-air heat exchanger.
[0077] The tub 1 is connected to a pump 12 via a suds draining duct 19 which facilitates the discharge of an aqueous liquid 11 , for example suds, from the tub 1 . A waste water conduit 13 directs the aqueous liquid 11 out of the washer-dryer. The drum 2 is driven by a drive motor 4 .
[0078] The drum 2 is filled through a door 22 that allows the access to the interior of the drum 2 with laundry 16 to be treated. In order to wash laundry 16 in the washer-dryer, the washer-dryer is connected to a water feed line 20 . The water feed line 20 is connected to a detergent rinsing shell 21 from which detergent and auxiliary agents can be flushed into the tub 1 with the aid of water from the water feed line 20 to allow a washing process in the washer-dryer. In this embodiment, this is achieved through a part of the process air circuit 5 and a sleeve 23 .
[0079] For drying wet laundry items in the drum 2 of the washer-dryer illustrated in FIG. 4 , which operates according to the principle of circulating air, air heated by an air heater 7 (“process air”) is driven through the process air circuit 5 with the aid of a blower 6 . Heated process air then enters the tub 1 and the drum 2 , respectively, through the sleeve 23 . The humid and warm process air resulting from the passage of the process air through the drum 2 , where it has taken up moisture from the wet laundry items 16 , arrives at a rear exit 24 of the tub 1 and thereafter at the heat exchanger 8 . In the air-air heat exchanger 8 , the process air is cooled with cold air and the moisture contained in the process air condenses. The condensate may be collected in a condensate container (not shown) or may flow back to the tub 1 and finally to the suds draining duct 19 whereby it can be discharged through the waste water conduit 13 . The dried air flows inside the process air circuit 5 , is heated again by the air heater 7 and then introduced again via the sleeve 23 into the drum 2 . Filled arrows 17 indicate the flow of the warm air. Short, unfilled and unnumbered arrows indicate the flow of the cooling air inside the air-air heat exchanger 8 .
[0080] In the embodiment shown in FIG. 4 , a first temperature sensor 14 is placed in the flexible hose 25 , such that the first temperature sensor 14 is allowed to be at least partially immersed in an aqueous liquid 11 contained in the tub 1 when the washer-dryer is operated in a washing or rinsing phase.
[0081] In the embodiment of the washer-dryer shown in FIG. 4 , the first temperature sensor 14 is placed in the lower part of the flexible hose 25 . Moreover, the first temperature sensor 14 is inclined toward the tub 1 .
[0082] In order to allow a more precise control of a drying phase in the washer-dryer, a second temperature sensor 27 is placed in the process air circuit 5 close to the door 22 .
[0083] The washer-dryer of FIG. 4 is configured for an operational method whereby a washing or rinsing phase involving an aqueous liquid 11 is conducted such that the first temperature sensor 14 is at least partially immersed in the aqueous liquid 11 . Moreover, the washer-dryer is configured for conducting the method under forced convection to increase a flow around the first temperature sensor 14 . This can be achieved by using the blower 7 during a washing or rinsing phase such that a strong flow of air is directed to the aqueous liquid 11 in the tub 1 which is then driven in the direction of the first temperature sensor 14 .
[0084] A drying phase is usually carried out by circulating process air repeatedly through the process air circuit until a desired degree of dryness in the laundry items is obtained. The washer-dryer of FIG. 4 allows a precise control of the drying phase in that the drying phase is conducted by controlling the blower 6 and the air heater 7 such that a set maximum process air temperature T max is not exceeded.
[0085] A sensor 33 for measuring the hydrostatic pressure p in the suds container 1 is also provided.
[0086] The washer-dryer of the embodiment of FIG. 4 has a rinsing device 10 for the heat exchanger 8 which can be connected to a water supply system such as the water feed line 20 via a water valve 9 .
[0087] FIG. 4 shows also a control unit 18 which controls the operation of the washer-dryer based at least partially on signals received from the first and second temperature sensor. The water valve 9 , the air heater 7 and a water heater 32 are all controlled by the control unit 18 as a function of a pre-programmed workflow. The program may utilize a timer signal. Further, the program may utilize signals based on sensed conditions such as the level of an aqueous liquid, for example the suds level, suds temperature and the speed of the drum 2 . | A washer-dryer including a tub, a drum mounted in the tub to be rotatable around an essentially horizontal axis for receiving laundry items, a process air circuit comprising an air heater and a blower to heat and circulate the heated air through the drum, a heat exchanger to condense moisture from the process air exiting the drum, and at least one temperature sensor, wherein at least a part of a surface of the temperature sensor is formed from a hydrophobic material, and a method for operating the washer-dryer. | 3 |
This application is a division of application Ser. No. 08/474,312 filed Jun. 7, 1995, (now U.S. Pat. No. 5,591,486); which is a division of application Ser. No. 08/323,693, filed Oct. 18, 1994, (now U.S. Pat. No. 5,458,919); which is a continuation of application Ser. No. 08/203,757, filed Mar. 1, 1994, (now U.S. Pat. No. 5,385,763); which is a continuation of application Ser. No. 07/917,531, filed Jul. 20, 1992, abandoned; which is a division of application Ser. No. 07/686,283, filed Apr. 16, 1991 (now U.S. Pat. No. 5,156,881); which is a continuation of application Ser. No. 07/169,577, filed Mar. 17, 1988, abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to a thin film forming method and a thin film forming apparatus, and more particularly to a method and apparatus for forming a thin film on a surface of a substrate having a trench or an unevenness thereon, e.g., a semiconductor substrate.
2. Description of the Prior Art
The processes usually used to form a thin film on a surface of a substrate, such as a semiconductor, are classified broadly into Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD).
The CVD process induces a chemical reaction on the substrate surface or in gaseous phase to form a thin film on the substrate, and this process is used to form insulation films such as a silicon oxide film or a silicon nitride film. The PVD process forms a thin film utilizing collision against a substrate of depositing materials generated in the gaseous phase, and this process is mainly used for metal film forming.
To achieve satisfactory results, VLSI device fabrication presently requires that a thin film be deposited within a trench formed in the substrate having an aspect ratio one or more (depth/width).
FIG. 22 is a sectional diagram showing a typical conventional plasma CVD process of the prior art (for example, J. L. Vossen & W. Kern, Thin Film Processes: Academic Press, 1978). In this process, an insulating film 53 is formed by depositing the deposit materials 52, which is in the solid phase generated in gaseous phase within a trench 51 of high aspect ratio formed on a substrate 50, such as silicon. However, the deposit material is deposited heavily on an edge 54 of the trench 51, thereby obstructing other deposit material from entering toward a bottom 55 of the trench 51. Thus, a cavity 56 is formed within the trench 51 and there is a degradation of stage coating properties on the substrate surface.
To cope with the above problem, a process called bias sputtering process, which is one of the PVD processes, is employed (for example, T. Mogami, M. Morimoto & H. Okabayashi: Extended Abstracts 16th Conf. Solid State Devices & Materials, Kobe, 1984, p. 43). This method is to form an insulating film, such as a silicon oxide film, by physically sputtering the substrate surface with ions of argon, for example. In the application of this method, the sputtering makes it difficult to have much deposition on edges, as shown in FIG. 22, and promotes heavier deposition on the flat surface portions. Therefore, the problems of forming the cavity 56 and of the stage coating properties are reduced in comparison to the CVD process above.
However, as the deposit material in gaseous phase comes into the trench on a slant, it is difficult to achieve a good filling within the trench with an aspect ratio of one or more. This method actually has a low deposition velocity, which means a very low productivity, because of the competing reactions between the removal of the deposited film and the film deposition by physical sputtering. In addition, radiation damage is inevitable because the process is conducted in the plasma.
Recently, an ECR bias sputtering method (for example, H. Oikawa; SEMI TECHNOLOGY SYM, 1986, E3-1) was proposed to reduce the oblique incident element of the deposit material within the trench. This method lessens the above-mentioned problem of the oblique incidence of the deposition material within the trench even though the deposit material is in the solid state, but it is not a complete solution. Appropriate forming of a thin film with a trench of the high aspect ratio is still difficult.
Other than the processes described above, a method to form a silicon oxide film using thermal decomposition method a TEOS (R. D. Rung, T. Momose & Nagakubo; IEDM. Tech. Dig. 1982, p. 237) has been proposed. This method, as shown in FIG. 23 (a), has a large surface movement rate of the deposit material, which makes cavity forming difficult, and realizes good stage coating properties. However, when an oxide film 57 having trenches formed by this method is cleaned, for example with diluted HF solution, the removal velocity of the oxide film 57 at the center of the trench 51 is extremely-high, as shown in FIG. 23 (b), and as a result, flat filling actually cannot be achieved. The reason seems to be the fact that the distortion of the oxide film grown from both sides of the trench remains around the center. It is thus considered extremely difficult to fill a trench with a high aspect ratio, even when a conformable thin film forming method is employed.
In FIG. 23 (a), after formation of an oxide film with impurity as a solid phase diffusing source using the thermal CVD method etc., a thermal process may be applied to diffuse the impurity around the trench of the substrate. However, when comparing an oxide film formed on the side wall of the trench and that on a flat surface, the former has less impurity density, and a desired resistivity cannot be obtained with this method.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved thin film forming process and a forming apparatus for this process which enables a good filling within a trench of high aspect ratio with films of an insulating material, a semiconductor material, and a metal, etc.
This invention solves the problems of the prior art in thin film forming with a trench having a high aspect ratio formed on above-mentioned substrate, such as semiconductors etc., such as cavity forming in the trench, degraded stage coating properties on the substrate surface, or radiation damage against the substrate.
BRIEF DESCRIPTION OF DRAWINGS
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
FIGS. 1 (a) (b) and (c) are sectional view illustrating steps of a method in accordance with the invention;
FIGS. 2, 3 and 4 are partial sectional views illustrating forming apparatus in accordance with several embodiments of the invention;
FIGS. 5 and 6 are graphs illustrating functions in accordance with embodiments of the invention;
FIG. 7 is a state diagram illustrating relationships of pressure and temperature in accordance with the embodiment of the invention;
FIG. 8 is a graph illustrating the relationship of the deposition velocity and the pressure in accordance with the embodiments of the invention;
FIGS. 9, 10(a) and 10(b) are sectional views illustrating the functions in accordance with the embodiment of the invention;
FIGS. 11, 12, 13, 14, and 15 are graphs illustrating different relationships of parameters in accordance with the embodiment of the invention;
FIGS. 16 and 17 are partial sectional views illustrating forming apparatus in accordance with other embodiments of the invention;
FIG. 18 is a graph illustrating the relationship of the deposition velocity and the substrate temperature in accordance with the invention;
FIGS. 19, 20(a) and 20(b) are sectional views illustrating the steps of a method in accordance with another embodiment of the invention;
FIG. 21 is a sectional view illustrating a semiconductor device in accordance with another embodiment of the invention;
FIG. 22 is a sectional view illustrating a conventional method;
FIG. 23(a) and 23(b) are a sectional views illustrating steps in accordance with an another conventional method; and
FIG. 24 is a typical state diagram.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention provides a thin film forming method together with a device for that method, which cools the substrate not more than the liquefaction point of the deposit species, so that the deposit species in the gaseous phase can exist on the substrate surface under more stable conditions than those when the deposit species are flowing in the gaseous phase.
Referring to FIG. 1, the function of the thin film forming method of this invention is explained below.
In FIG. 1 (a), deposit species 32 in a gaseous phase state is deposited within a trench 31 with high aspect ratio formed on a substrate 30, such as a semiconductor. The substrate is cooled to a temperature of not more than the liquefication temperature point of the deposit species 32, so the species 32 liquefies and adheres on the substrate surface. The reference number 33 represents a thin film formed within the trench 31 by the deposit species 32.
By repeating this process, as shown in FIG. 1 (b), thin films 33a are built up within a trench 31 to form a filling. If the process is continued after the complete filling up of the trench 31, thin film 33b is formed appropriately over the trench 31 and on the surface of the substrate 30.
To explain this phenomenon, FIG. 24 shows, with parameters of the temperature and the pressure, three phases (gaseous phase, liquid phase and solid phase) of an active species of a first reactive gas, a second reactive gas, or their reaction product. As the temperature of the material including the reactive gas, etc., described above, decreases, the state changes from the gaseous phase A to the liquid phase B. In a high pressure condition, transfer from gaseous phase A to liquid phase B becomes distinctive.
For example, if a reactive gas with pressure P O is in the state of gaseous phase A, when the temperature is lowered to t 0 (the boundary between the gaseous phase and the liquid phase, i.e., the liquefication point) or below, the state changes to the liquid phase.
If the temperature drops more, the state goes to the solid phase. Therefore, this invention utilizes the temperature dependency of three phases above for the trench filling in semiconductor fabrication. When only one kind of gas is used, the substrate temperature shall be set not more than the liquefaction point of that gas.
As described above, this invention provides an excellent flatness after the appropriate filling or plugging of trenches with a high aspect ratio at a low temperature, and is an optimum for VLSI fabrication.
A first embodiment of the thin film forming process according to this invention is described below.
Firstly, an apparatus for this process is explained. FIG. 2 is a schematic configuration illustrating the apparatus according to one of the embodiments of this invention to be used for this process. The configuration of this apparatus is given below.
In a reaction vessel 1 is accommodated a substrate 3 located on a sample holder 2. To the reaction vessel 1, active species of a first reactive gas 6 and a second reactive gas 7 are introduced through the gas introducing pipes 4 and 5, and are exhausted through the exhaust pipe 8 connected to the exhausting system. The flow rate of the first and the second reactive gases can be adjusted with a mass-flow controller (not shown). The first reactive gas 6 is activated in a microwave discharge portion 9 connected to the above mentioned gas introducing pipe 4. The gas introducing pipe 4 is made of a quartz in this embodiment.
Microwave power is supplied from a microwave power source 10 through a waveguide 11 to the discharge portion 9. Activation of the reactive gas 6 is performed with plasma in this embodiment, but it may be done with thermal excitation, optical excitation or electron beam excitation. Pressure in the vessel 1 is set by changing the conductance of a valve (not shown), and is measured with a diaphragm vacuum gauge (not shown) to be controlled.
Within the above mentioned holder 2, a cooling means 12 is provided to cool the substrate 3, and an additional heating means 13 can be provided, if required. These means are connected to a control system (not shown) to monitor the temperature of the substrate 3 and keep it at a fixed value not more than the liquefaction point of the active species generated from the first reactive gas, the second reactive gas and their reaction products.
The cooling means 12 carries nitrogen gas coming through as liquid nitrogen to the holder 2 via a cooling pipe (not shown). The cooling means is controlled by adjusting the flow rate of the nitrogen gas with a needle valve (not shown) provided in the cooling pipe. A heater is used for the heating means 13, but the cooling and the heating means are not limited to those described above, and anything that can keep a constant temperature is acceptable. The substrate is fixed to the above mentioned sample holder so that the substrate can make good thermal contact with the sample holder.
Areas of the substrate other than the reaction vessel 1 and the sample holder 2 may have a structure, for example, with an electric current heater wound around the wall of the vessel 1, to maintain the space in the reaction vessel 1.
As a thin film forming apparatus relating to this invention, other embodiments shown in FIG. 3 and 4 may be utilized. The apparatus shown in FIG. 3 is almost the same as the configuration of the apparatus of FIG. 1, and the same parts are shown with the same reference numbers. The difference of this apparatus from the one in FIG. 2 is that a light radiation means 16 to radiate a beam 15, e.g., electron, ion or laser beams, is provided. This light radiation means 16 enables excitation of the reactive gas with a light. By using this light excitation, as with the apparatus shown in FIG. 2, the damage to the substrate 2 and other adverse influences may be reduced.
Although it is not shown in the figures, the substrate 3 extends into and out of the reaction vessel 1 through another adjacent chamber. This chamber may be evacuated, or may contain an inert gas with atmospheric or higher pressure. By this "load-locking" of the reaction vessel 1, reproducibility of the process may be remarkably improved.
The thin film forming apparatus shown in FIG. 4 also has almost the same configuration as the one shown in FIG. 2, and the same parts as in FIG. 2 are indicated with the same reference numbers. These reference numbers show a thin film forming apparatus capable of post treatment after the thin film is formed. In this apparatus, after the thin film is formed on the substrate 3, the substrate 3 is carried through a carrying system 17 to a thermal treatment chamber 18 by a carrying mechanism (not shown). The substrate 3 carried to the thermal treatment chamber 18 is placed on a holder 20 equipped with a heating means 19, and a thermal treatment is applied to the substrate. This heating may be conducted by raising the substrate temperature instantaneously with radiation from an infrared lamp 21.
By conducting the thermal treatment above, residue, dust, etc., on the surface of the substrate 3 can be removed, and the film quality of the thin film can be improved.
In the same figure, a reference number 22 indicates a gas inlet port for introducing an inert gas Z 23, and the reference number 24 is a gate valve dividing the reaction vessel 1 and the thermal treatment chamber 18.
An embodiment of thin film forming process according to this invention is described below. This explanation refers specifically to the apparatus shown in FIG. 2, but any of the apparatuses described above can be used for this process.
In this embodiment, oxygen (0 2 ) is used as a first reactive gas, and tetramethylsilane (Si(CH 3 ) 4 ; TMS) as a second reactive gas. Using a silicon substrate as a substrate, a silicon oxide film is deposited on this silicon substrate. First, oxygen gas 6, which is the first reactive gas, is introduced through the gas introducing pipe 4 and microwaves of 2.45 GHz are discharged to produce an oxygen radical (0*). Then, this oxygen radical is moved to the reaction vessel 1. Meanwhile, TMS is introduced to the reaction vessel 1 without discharging. The total pressure in the reaction vessel 1 is fixed at 2 Torr. The sample holder 2 has a built-in stainless steel pipe 12. Cooling nitrogen (N 2 ) gas passes through the liquid nitrogen and flows through the pipe 12 to lower the temperature of the substrate 3.
FIG. 5 shows the deposition velocity of the silicon oxide film at variable substrate temperatures in the above process, and the resulting configuration of a trench on the substrate. The flow rates of oxygen and TMS are 56 SCCM and 7 SCCM, respectively, and the trench has an aspect ratio of 1.5.
It is seen from this graph that the deposition velocity represented by the curve A reaches the highest point when the substrate temperature is -40° C. For the filled trench configuration, at a temperature above room temperature, the silicon oxide film formed by the reaction of the O* radical and TMS forms a cavity as described in the prior art.
On the other hand, with the decrease of the substrate temperature, the intensive deposition on the trench corners decreases and at the substrate temperature of -20° C. or less, the thin film can fully fill the trench.
FIG. 6 shows the deposition velocity and the deposition configuration at the different substrate temperatures when the flow ratio of oxygen to TMS is 24. Conditions other than the flow ratio are the same as in FIG. 5. FIG. 6 shows a tendency similar to that seen in FIG. 5. It is observed that this process is optimum for the formation of an interlaminar insulation film in the multilayer wiring technique.
The inventors of this invention have made a further study to find optimum conditions for forming a thin film within a trench. Details are described below.
FIG. 7 is a phase diagram of hexamethyldisiloxane and trimethylsilanol which can be reaction products by tetramethylsilane (TMS)-oxygen (0 2 ) active species and tetramethylsilane. As described in the embodiment above, when the interior pressure of the reaction vessel is 2 Torr, the trench interior can be filled if the substrate temperature is lowered to about -20° C. It is assumed from this phase diagram that the liquid used in the deposition includes tetramethylsilane and/or hexamethyldisiloxane at a substrate temperature in the range of 20° C. to -100° C. and a vessel internal pressure of less than 10 Torr. It is also considered that oxidation proceeds while entrapping active oxide species in the liquid layer. This assumption may be reasonable since the infrared absorption spectra of this film is nearly identical to that of the plasma polymerization film of hexamethyldisiloxane.
Thus, when the internal pressure of the reaction vessel is 2 Torr, the substrate temperature is required to be not more than -22° C. where hexamethyldisiloxane is liquid and not less than -100 ° C. where tetramethylsilane is a solid.
Consequently, it is necessary to arrange an appropriate thermal contact between the substrate and the sample holder, a uniform distribution of sample temperature, and a correctly measured and controlled temperature to make the liquefiction possible.
FIG. 8 is a diagram showing the deposition velocity and the deposition configuration with changes of internal pressure of the reaction vessel. The substrate temperature is set at -40 ° C., and the flow rate of TMS and oxygen at 7 SCCM and 168 SCCM respectively. As a result, the deposition forms a large lump on the substrate surface around 10 Torr, and the trench cannot be filled. As the pressure decreases, however, filling becomes possible and the deposition velocity increases.
The shape of a globule 90 adhered on the substrate surface as a lump can be expressed by the formula below in the coordinates shown in FIG. 9, using a Laplace equation:
γ(1/R+Sin φ/r)=ρgz+ΔP.sub.O
where, the reference number 91 indicates the substrate; the main curvature of the curved surface in the plane of the figure is r/sinφ, and the main curvature perpendicular to this is R, γ represents the surface tension, ρ is the liquid density and ΔP 0 is the pressure difference between the inside and the outside of the globule 90. If the globule 90 is rotationally symmetrical and the two main curvatures at the apexes are equal to b, according to the equation above,
γ·2/b=ΔP.sub.O
This means that when the pressure difference ΔP 0 is larger with an equal surface tension γ, the radius of curvature b of the apexes becomes smaller, and results in a long shaped globule as shown in FIGS. 10a and 10b. As the pressure of the microwave discharge changes, the types and the quantity of the oxygen active species may change, the functional group produced on the silicon substrate surface may change, and the contact angle to the hexamethyldisiloxane or tetramethylsilane may change.
For these reasons, even in the pressure and temperature range of liquefication, it is suitable to set the pressure at the contact angle in the range where liquid flows into the inside of the trench, and it is preferable to have a pressure of 10 Torr or less for the process of this embodiment.
The appropriate pressure should not be less than the temperature of the triple point of hexamethyldisiloxane or tetramethylsilane, so that they will be liquefied.
FIG. 11 shows the deposition velocity and deposition configuration change to the flow ratio of oxygen and tetramethylsilane. From this figure, it is seen that the deposition velocity reaches its peak when the oxygen/TMS flow ratio is around 20. The trench can be filled with an approximate oxygen/TMS flow ratio of 4, and the trenches can be filled at ratios not less than this value. The reason for this phenomenon is considered to be the fact that, in the formation of hexamethyldisiloxane from oxygen and TMS, the following reaction occurs. ##STR1## where, oxygen/TMS equals 2. Therefore, when tetramethylsilane is 7 SCCM, the oxygen is required to be 14 SCCM or more, and the flow ratio is preferably at least 2 or more for an ideal reaction.
FIG. 12 shows infrared absorption spectra of a deposited film for oxygen/TMS flow ratios of 8 (graph A), 24 (graph B) and 40 (graph C). An absorption peak of Si--O--Si is observed in the range from 1200 cm -1 to 1000 cm -1 , and the film is confirmed to be a silicon oxide film.
Strength changes of the absorption peaks of Si--CH 3 , Si--H, O--H specified by this Si--O--Si absorption peak to oxygen/TMS flow ratio are shown in FIG. 13. From this figure, it is seen that the larger the oxygen/TMS becomes, the more the silicon oxides. Reference numbers in circles 1 through 7 correspond to the references in FIG. 12.
Next, a study of the characteristics of the thin film formed with the present invention is described below. As shown in FIG. 14, the oxygen/TMS flow ratios at varying velocities of etching on the deposited film are determined using a solution including 6% of HF and 30% of NH 3 F. These determined values show that, as oxygen/TMS increases, the etching velocity decreases and the film is further nitrogenized. Thus, it is found preferable to increase the oxygen flow rate and make the oxygen/TMS flow ratio larger for a good quality film deposit.
After the thin film deposition on the substrate, the substrate is thermally treated in the reaction vessel with the two methods below.
(1) Maintain the substrate temperature at 300° C. in oxygen of 10 Torr for 1 hour.
(2) While discharging microwaves into the oxygen of 2 Torr, maintain the substrate temperature at 300 ° C. for 1 hour.
The absorption strength changes of Si--CH 3 , Si--H and O--H specified with the Si--O--Si peak absorption of the infrared absorption spectra for the film obtained from the above versus oxygen/TMS flow ratio is shown in FIG. 15. The combination of Si--CH 3 and O--H decreases first during the thermal treatment of (1), and second during the thermal treatment in (2), and the silicon oxidization proceeds. It was found that the combination of Si--H disappears during the treatment processes of (1) and (2). In conclusion, to improve the film quality of the deposited film, the substrate temperature should be at least 300° C. The thermal treatment in (1) and (2) above can promote oxidization of silicon, and it has been observed that, in particular, the oxidization caused by the thermal treatment process (2) is remarkable.
Radiation of an ArF excimer laser with a wave length of 193 nm during the film forming activates the liquefied layer or substrate surface, resulting in a further flatness of the filled trench through experiments. Radiation energy of the ArF excimer laser is then 330 Joul/cm 2 sec. As the activation proceeds more when the energy is not less than this value,
this activation will occur when the energy is 330 Joul/cm 2 or higher. This activation is performed by an impact with ions, electrons, etc., on the substrate surface, and this will enhance the surface migration of the active species to the thin film to promote the flatness of the filled trench surface.
The above-mentioned thin film forming apparatuses have separated vessels including one for plasma forming and another for the reaction. The invention may be also applied to the one vessel type thin film forming apparatus.
FIG. 16 is a schematic view showing a thin film forming apparatus according to one embodiment of this invention. In FIG. 16, 101 denotes a grounded vacuum vessel forming the reaction vessel. Prescribed first and second reactive gases are introduced into the reaction vessel 101 through a gas inlet 102. The mixed gas contained in the reaction vessel is exhausted through a gas outlet 103. In the reaction vessel 101, a cathode (first electrode) 105 is disposed opposite the top wall of the vacuum vessel serving as an anode (second electrode).
On the first electrode is placed a substrate 106, and a cooled nitrogen gas is passed over this electrode for cooling. A heating device (not shown) is also provided to raise the temperature. Further, the first electrode is connected to a high frequency power source 109 through a matching circuit 108. A heater 111 is coiled around a wall 110 of the reaction vessel 101, thereby preventing adhesion of the deposition film. Although it is not illustrated, another vacuum vessel which is vacuous or filled with an inert gas is disposed between the above reaction vessel 101 and the atmosphere for loading and unloading the substrate 106.
Thus, the reliability of the process is greatly enhanced by making the reaction vessel a so-called load-lock type. In the same drawing, 116 denotes an insulator. Further, another embodiment is shown in FIG. 17. Parts identical with those shown in FIG. 16 are assigned the same reference numbers.
In this embodiment, a thin film was deposited on a substrate 106 in the same way as in the above embodiment and the substrate 106 was moved to another reaction vessel 112 with a carrier (not shown) and placed on a holder 113 and heated thereon by a heating means (not shown). In addition to the heating from the substrate side, this heating treatment may be effected by raising the substrate temperature instantaneously with an infrared lamp irradiated just above the substrate 106, for example. Further, an inert gas or the first reactive gas may be introduced through a gas inlet 102a during this heating treatment. Also, a high frequency power source 109 is connected via a matching circuit 108, so that the plasma can be generated during the heating treatment.
In the drawing, number 115 denotes a gate valve. This invention may be applied in various ways. For example, a magnetic field may be supplied from outside between parallel plate electrodes applied with the above RF power as a means to generate the plasma, thereby generating a high-density plasma. Also, electrical discharge may be generated by ECR (Electron Cyclotron Resonance) discharge, a hollow cathode discharge, or by supplying high frequency power from outside with the substrate disposed in a vacuum vessel of an insulator, such as a quartz.
Another thin film depositing process according to the present invention using the apparatus shown in FIG. 16 will be described below. Oxygen and a tetramethylsilane Si(CH 3 ) 4 (TMS) as the first and second reactive gases are inserted into the reaction vessel 101.
FIG. 18 shows how the silicon oxide film is formed on the silicon substrate. The lateral axis indicates the temperatures of the substrate and the vertical axis shows the deposition velocity. The cross sections show different filled shapes formed within the trench of the substrate. The plasma is generated by applying an RF power of 13.56 MHz between the first and second electrodes to cause a high frequency electrical discharge. In the reaction vessel, oxygen is introduced at a rate of 40 cc/minute and TMS of 5 cc/minute. The total pressure is 5×10 -3 Torr.
A magnet is disposed on the second electrode side to allow high-density plasma to be obtained. It is seen from FIG. 18 that the deposition velocity exhibits a maximum value with respect to changes of the substrate temperature. It is seen by observing the filled shape within the trench, that when the aspect ratio of the trench is one or more, SiO 2 produced by the reaction of the oxygen radical and TMS in the gaseous phase at a temperature above room temperature as shown in FIG. 18(c) is deposited on the substrate similar to falling snow, as seen in the so-called conventional plasma CVD process, and the cavity is formed.
On the other hand, it is seen that with a decrease of the substrate temperature, the deposit which is predominantly formed on the corner of the trench is reduced and when the substrate temperature is -20° C. or less the trench can be completely filled. This phenomenon is believed to take place in the following manner. The reaction products of the oxygen radical and TMS, such as hexamethylsiloxane (Si(CH 3 ) 2 ) 2 O and trimethyldisiloxane Si(CH 3 ) 3 OH, liquefy at the temperatures as shown in FIG. 18 and liquid is formed as a layer on the substrate surface. This liquid layer catches therein SiO 2 species which have further reacted in the gaseous phase.
It is believed that the oxidation proceeds accompanying the inclusion of the oxygen radical and the tacking in of the oxygen ions. On the other hand, the above liquid layer is finely dispersed over the substrate surface and therefore it exists most stably on the bottom corner of the trench to provide a large contact area in the substrate surface. As a result, observation of deposition over time indicates that the deposit is first formed on the corner. Therefore, as shown in FIG. 19, the deposit accumulates from the bottom of the trench upward to form a film, making it possible to fill a trench with a high aspect ratio and to provide a very even surface, which could not be done heretofore.
It is possible also to form a film at a low temperature. This is effective for the formation of an interlaminar insulation film in the multilayered wiring process. Using nitrogen or NH 4 instead of oxygen, a silicon nitride film (Si 3 N 4 ) can be formed. It is needless to say that by using a material containing at least one element which is included in groups II to VI of the periodic table as the second reactive gas and suitably varying the substrate temperature, oxide and nitride can be formed readily.
It is also needless to mention that the gas pressure in the reaction vessel is not limited to the above-mentioned 10 -3 Torr but can be selected to fall in the most effective pressure range according to the discharging method and the reactive gas used.
Addition of an inert gas such as argon or helium to the first reactive gas prolongs the service life of the deposition species as a metastable active species and provides more effective deposition. The reaction gas to be used may be one type and a desired film may be deposited by a process such as thermal decomposition. It was experimentally confirmed that in the process of forming the film, the irradiation with an excimer laser having a wavelength of 193 nm, or with ions, electrons or the like, enhances the activity of the above liquefied layer, increasing the surface migration of the active species within the layer and completing the filling of the trenches, making the film completely flat.
In the formation of the above silicon oxide film, when impurities such as POCl 2 , PCl 3 , PH 3 , BCl 3 ,B 2 H 6 and AsH 4 are added to TMS, for example, the oxide film produced includes these impurities. This film fills the trench. Then it is heated instantaneously with a heater or a lamp, for example. This disperses the impurities into the silicon substrate. Heretofore, an oxide film containing the impurities along the walls was produced by the thermal CVD process. However, the concentration of the impurities contained in the oxide film which is formed along the side walls of the trench is lower than in the planar portion. Thus, a desired specific resistance could not be attained from the side walls.
The oxide film according to the present invention includes the impurities in a very uniform amount as shown in FIG. 19 describing the depositing state with the lapse of time. Therefore, after depositing, as shown in FIG. 20, a thermal treatment is given to remedy the above drawbacks completely. The dispersion layer as shown in FIG. 20 is essential to provide a sufficient memory capacity for large scale memory devices, such as 16M and 64M DRAMs. The above thermal treatment, when effected after the film formation, for example in situ within the treating chamber as shown in FIG. 16 or FIG. 17, can completely avoid the contamination by the impurities other than the prescribed impurities, such as carbon, nickel and other heavy metals. Thus, a high quality film is deposited.
The inclusion of gas containing a hydrogen and a halogen element in the reactive gas reduces the methyl group contained in the TMS, and more stable CH 4 and CH 3 Cl are produced and removed, resulting in the lowering of the concentration of the carbon impurities. Thus, the film quality is much enhanced. AsH 4 is used as an impurity to be added to the second reaction gas in this example, but in case of phosphor (P) diffusion, a material such as POCl 3 , PCl 3 and PH 3 which reacts with the first or second reactive gas element to produce phosphor, may be used. In case of boron (B) diffusion, BCl 3 , B 2 H 6 , etc., may be used. For example, it was confirmed that when the organic metal compounds such as Al(CH 3 ) 3 , Ti(C 5 ) 2 , carbonyl metals, such as W(CO) 6 and Cr(CO) 6 , and halogenated metals are used together with hydrogen and nitrogen, metals can entirely fill in a space with a high aspect ratio, such as a contact hole.
In addition to the above thin film forming, using for examples GeH 4 , SiH 4 , SiCl 4 , GeCl 4 , and a gas including at least silicon, the deposition of silicon and germanium can be done. Using As(CH 3 ) 3 , AsH 3 , GA(CH 3 ) 3 and GaH 3 , GaAs and other group III-V compounds can be deposited and using a reactive gas containing indium and phosphor, InP and other group II-VI compounds can be deposited.
Further, using a reactive gas containing at least carbon and hydrogen, various high molecular organic films can be deposited. For example, when methylmethacrylate (MMA) is introduced and the substrate temperature is lowered to -30° C. or less, PMMA, which is used for an electron beam resist, can be formed.
Proceeding now to the explanation of another embodiment relating to the thin film forming process of this invention, a macromolecule thin film forming process using hydrogen, nitrogen or gases including a halogen element, such as SiCl 4 , as the first reactive gas, and a gas at least including carbon and hydrogen as the second reactive gas, is described below. This process is basically the same as above-mentioned embodiment, and is briefly described with reference to FIG. 3.
The substrate used here has an unevenly configured surface provided with the trench having an aspect ratio of one or more. Nitrogen (N 2 ) gas is used as the first reactive gas, and N* radical is introduced into the reaction vessel by discharging. Methylmethacrylate (MMA) is introduced as the second reactive gas and the exhaustion is conducted.
The substrate temperature is cooled to -30° C. or less. This results in the covering of the unevennness on the surface of the substrate with a film of PMMA, a polymer of MMA, for the same principle as the one illustrated in FIG. 1, to achieve a super flatness. The PMMA film is widely used as an electron beam resist.
Another embodiment relating to the thin film forming process of the present invention is explained below. FIG. 21 is the sectional view of the final process showing the formation of the source, a drain electrode and a wiring for a MOS transistor using the process of this embodiment.
A gate oxide film 71 and a gate electrode 72 are formed on a silicon substrate 70, and the source and the drain areas 73, 74 are integrally formed to the gate. After the coating of the entire surface with a silicon oxide film 75 using a CVD process, etc., the silicon oxide film 75 on the source and the drain 73, 74 is partially removed by etching to form a contact holes 76 with an aspect ratio of one or more.
A wiring 77 for the source and the drain electrodes is next formed with the method of this invention. In particular hydrogen is used as the first reactive gas and Al(CH 3 ) 3 as the second reactive gas, and the substrate temperature is set at a specified value to fill the aluminum electrode wiring 77 completely into the contact hole 76 and form a super flatness by repeated deposition. After patterning of the electrode wiring 77, a silicon oxide film 78 is formed as protective film all over the surface. This protective film 78 can be formed by the process of this invention. By covering the wiring and the trenches formed by the CVD oxide film 75 with a protective film utilizing the same method as shown in the first embodiment, a flat film can be formed.
In this embodiment, the mechanical vibration of the substrate 70 during the forming of the electrode wiring 77 disturbs a trench retaining layer (a stagnant layer) of the gaseous phase to promote the deposition of the aluminum film on the substrate 70. Such vibration of the substrate itself, or the gaseous phase during the thin film forming is effective to increase the deposition velocity and to improve the film quality.
As a means to create vibrations, a motor, etc., may be provided at the sample holder 2, as shown in FIGS. 2 through 4, to produce the mechanical vibration, or a supersonic wave oscillator may be incorporated in the holder 2.
Although, aluminium is used for the metal filling the trenches, such as the MOS transistor contacts, etc., in this embodiment, the second reactive gas can be Ti(C 2 H 5 ) 2 , carbonyl metal, such as W(CO) 6 or Cr(CO) 6 , or halide metal, etc., instead of Al(CH 3 ) 3 .
Embodiments of the present invention are explained above and some additional examples are described below. In place of the oxygen discharge in these embodiments, gases at least including an oxide, such as N 2 0, can be used. By using nitrogen or NH 3 , formation of a silicon nitride film is possible. When using a gas including at least one element of the second to sixth group in the periodic table, oxide films can produce nitride. The substrate temperature at that time can be set at a value not more than the liquefication points of the active species of the first reactive gas, the second reactive gas and their reaction product, depending on the type of gases.
Mixing inert gases such as argon or helium with the first reactive gas generates long-life metastable active species of these inert gases. These active species can carry the active species of the first reactive gas, and this results in high flexibility of the device design.
Other than the thin film forming above, for example, silicon or germanium deposition is possible using hydrogen as the first reactive gas and using a gas containing at least germanium or silicon such as GeH 4 , SiH 4 , SiCl 4 and GeCl 4 as the second reactive gas. Group III to V compound, such as GaAs can be deposited when the second reactive gas is As(CH 3 ), AsH 3 , Ga(CH) 3 or GaH 3 , and group II-VI compounds, such as InP, may be used when some reactive gas includes indium and phosphor.
The thin film forming process explained above using raw material gas of the thin film as the second reactive gas (for example, Al(CH 3 ) 4 +H 2 ) can produce the same effect.
In FIGS. 2 through 4, the rotating mechanism can be connected to the sample holder 12 for supporting the substrate 3 so that the substrate 3 is rotated at a high velocity and the reactive gas diffuses uniformly. The rotation may be at a fixed velocity, or may be intermittent to avoid a rotation of the gaseous phase with the substrate.
The configuration above can increase the deposition velocity more, and reduce variations in the deposition velocity and the deposition film composition on the substrate. Such variations result from the difference of the distance from the gas inlet port 4 and 5 to the surface of the substrate 3, even in the case of a large-sized substrate, such as a silicon wafer. For radiation by electrons, ions and light, such as a laser beam, this is convenient because it can compensate for beam variations, and a large diameter beam is not necessary.
A plurality of substrates can be simultaneously introduced to the reaction vessel in FIGS. 2 through 4. For example, with a reaction vessel in the shape of a rectangular parallelepiped, four surfaces are provided with substrates, another substrate is used for putting in and taking out the substrates, and another surface for vacuum exhaust and the introduction of the first and the second reactive gas. In this case, too, each substrate is placed an equal distance from the gas inlet port to form a uniform thin film.
As explained above, the invention can be changed without departing from the scope of the invention.
The invention can achieve a better filling than with the prior art without causing radiation damage of insulation, semiconductor, metal, etc., to realize a flatness even for the trench with a high aspect ratio. | A thin film forming method which comprises the steps of supporting a substrate to be treated, having a trench or an unevenness thereon, in a reaction vessel; introducing a reactive gas into the reaction vessel; activating the reactive gas to form a deposit species, the deposit species characterized by a phase diagram including a liquid phase region defined by a melting curve and an evaporation curve that intersect at a triple point; and forming a thin film containing at least a part of the deposit species on the substrate while retaining a pressure of the deposit species in the reaction vessel higher than the triple point of the phase diagram of the deposit species, and retaining a temperature of the substrate within the liquid phase region of the phase diagram of the deposit species. | 8 |
This application is a continuation of U.S. application Ser. No. 14/219,347 filed Mar. 19, 2014, the disclosure of which is incorporated by reference herein in its entirety.
BACKGROUND
The present invention relates to a hardware device simulation and device driver, and more specifically, to a self-verifying device driver for multi-version compatible data manipulation devices.
A data manipulation device is a hardware based product (e.g., microprocessor). Over the life cycle of the product, multiple different versions of the same physical device may be produced with upgrades or modifications. The underlying data manipulation remains in the same format for every version (backwards and forward compatible) even though different characteristics and options may exist among the versions. The device driver is a computer program that controls the data manipulation device. That is, the device driver provides a software interface to the data manipulation device and is used to issue commands to the data manipulation device to obtain output. The device driver maintains information regarding a pool of data manipulation devices and this pool can have data manipulation devices of multiple versions. The device driver is tested by executing test cases that issue commands to the device driver which in turn builds requests that are presented to the data manipulation device, implemented in hardware or as a simulation. The commands to the device driver from the test case may or may not specify a specific device version which must be used. When there is no device version specified, the device driver may choose any data manipulation device and build a command block for that version. When the device driver is coupled to a particular data manipulation device that it will send requests to, the device driver determines the version of that data manipulation device through a handshake or interrogation process.
SUMMARY
According to an embodiment, a system to test a device driver includes a first memory device configured to store programming code of the device driver, the device driver providing an interface to a data manipulation device; a second memory device configured to store a test case to test the device driver, the device driver receiving version information specifying a targeted version of the data manipulation device to be targeted by the device driver from the test case or the device driver determining the targeted version of the data manipulation device independently of the test case; a third memory device configured to store a simulation including a version verification portion and a data manipulation portion, the data manipulation portion remaining unchanged for every version of the data manipulation device; and a processor configured to execute the test case on the device driver, execution of the test case being configured to include, based on a request by the device driver, execution of the version verification portion of the simulation and, based on a result of executing the version verification portion, execution of the data manipulation portion of the simulation.
According to another embodiment, a non-transitory computer program product stores instructions which, when executed by a processor, cause the processor to implement a method of verifying a version of a data manipulation device in a request by a device driver under test. The method includes determining whether the version of the data manipulation device in the request is a match or a non-match with a targeted version of the data manipulation device, the targeted version being either specified in a test case being executed by the device driver or determined independently of the test case; and calling a data manipulation simulation based on the determining, the data manipulation simulation being unchanged for every version of the data manipulation device in the request.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with the advantages and the features, refer to the description and to the drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The forgoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a block diagram of a system that tests the device driver according to an embodiment of the invention;
FIG. 2 is a functional flow diagram of the simulation according to embodiments of the invention; and
FIG. 3 is a process flow of a method of verifying the device driver request according to embodiments of the invention.
DETAILED DESCRIPTION
As noted above, a device driver is a software program that controls a hardware based data manipulation device. The device driver is tested with test cases that specify parameters to the device driver which build requests to be passed to the data manipulation device. The data manipulation device can either be a software simulation, as referenced in this document, or an actual hardware device. The simulation is likely based on the initial data manipulation device version, but newer data manipulation device versions may require a slightly different request structure. While the device driver must be tested to ensure that it is sending the correct request based on the specified version of the data manipulation device, modifying or adding simulations for every version of the data manipulation device may be undesirable. It may also be undesirable to rework an existing body of test cases.
Embodiments of the systems and methods detailed herein relate to a verification layer between the device driver and the data manipulation implemented in a simulation of a data manipulation device. Because the verification layer separately verifies requests from the device driver with regard to version-specific characteristics, the verification layer facilitates maintaining the core simulation of the data manipulation device. Further, because of the handshake or interrogation procedure of the device driver with the data manipulation device (or simulation) that facilitates the device driver determining the version to address in subsequent requests, the regression test suite may also remain unchanged for every version of the data manipulation device. That is, for newer version of a data manipulation device, the test case would simply not specify a version at all.
FIG. 1 is a block diagram of a system 100 (add to FIG. 1 ) that tests a device driver 120 according to an embodiment of the invention. The system 100 (e.g., a computer system) includes an input interface 112 , one or more processors 114 , one or more memory devices 116 , and an output interface 118 . The memory device 116 may store the device driver 120 (programming code), the simulation 130 of the data manipulation device according to embodiments of the invention, and the test cases 140 . In alternate embodiments, one or more of the device driver 120 , the simulation 130 , and the test cases 140 may be stored in a memory device other than the memory device 116 that is accessible through the input interface 112 , for example. As shown, the system 100 running the device driver 120 programming code may be coupled to one or more hardware-based data manipulation devices. After successful testing, the device driver 120 may be used with a data manipulation device of any known version. The processor 114 processes the programming code of the device driver 120 for the various test cases 140 . The test cases 140 executed by the device driver 120 are verified using the simulation 130 . As further detailed below, the simulation 130 according to embodiments of the invention includes two portions or layers. In addition to the common simulation portion (core data manipulation) that is common to all versions of the data manipulation device, another portion (layer) is added to the simulation 130 to verify the request from the device driver 120 .
FIG. 2 is a functional flow diagram of the simulation 130 according to embodiments of the invention. The flow begins when the device driver 120 executes a test case 140 ( 210 ). As noted above, the test case 140 itself may specify a version of the data manipulation device for the device driver 120 to target. Alternately, the version may be determined by the device driver 120 independently of the test case 140 . That is, the test case 140 may not specify a version so that the device driver 120 can determine a (newer) version based on initial communication with the simulation 130 . The functional flow is separated into the version verification portion 220 and the data manipulation portion 260 . In the version verification portion 220 , a function 230 includes determining the version specified by the device driver 120 in its request. Another function 240 in the version verification portion 220 is determining whether the version specified in the request is the version that is expected. The version verification portion 220 of the simulation 130 knows both the version specified by the device driver 120 and the version that should have been specified by the device driver 120 in the following ways. The version verification portion 220 uses the following information: device information (handle for a specific version of the data manipulation device) per device driver 120 input/output; software token setup for each input/output that contains information about device driver 120 decisions and user request parameters (that led to those decisions); and the input/output request with associated input/output memory. This information used by the verification portion 220 is independent of whether the test case 140 specified the version or not. Using this information, the version verification portion 220 accesses the internal memory of the device driver 120 and indexes the internal memory with the information to determine the version of the data manipulation device and other characteristics known to the device driver 120 . The software token contains indicators of how the decisions were made about the request being built by the device driver 120 . That is, the software token provides the information about the correct version of the data manipulation device and the internal memory provides information in the device driver 120 regarding that version. The correct version information (from the software token and internal memory) may be cross validated with the version (request values) set up by the device driver 120 (determined as part of function 230 ) based on the input/output request information that the version verification portion 220 also uses. This cross validation facilitates the execution of the functions of determining whether the version is the expected version ( 240 ).
The execution of the function ( 240 ) to check the specified version versus the expected version results in the simulation 130 version verification portion 220 returning an error, discussed further below, to the device driver 120 when the version of the data manipulation device specified in the request from the device driver 120 does not match the version that was supposed to be specified based on the test case 140 being executed or the initial communication. When the version of the data manipulation device specified in the request from the device driver 120 does match the version that was supposed to be specified, the version-specific characteristics of the request are verified as part of the function 250 . The version-specific characteristics include, for example, the formatting of the request. When the version-specific characteristics are verified, the data manipulation portion 260 of the simulation 130 is executed. Regardless of the version of the data manipulation device, specified by the test case 140 or the initial communication, and the request from the device driver 120 , the data manipulation portion 260 of the simulation 130 is the same. When a new version of the data manipulation device is added, the new version is added to the version verification portion 220 in order to test the device driver 120 functionality with regard to the new version, but the data manipulation portion 260 (and initiating test case 140 ) remains unchanged.
When the version-specific characteristics are not verified as part of function 250 , an error is returned. Thus, whether the wrong version of the data manipulation device is specified by the device driver 120 or the wrong request characteristics targeting the correct version are included in the request by the device driver 120 , an error is output, and the simulation 130 is interrupted. The format of the error may be a hardware specific error code or a software specific error code. The error codes may fit into the existing structure (i.e., match error codes already set up for the existing data manipulation portion 260 of the simulation 130 ) such that additional changes are not required for the test case 140 targeting a specific (new) version of the data manipulation device. The error code may indicate a specific verification step of the simulation 130 (e.g., the expected version verification (function 240 ), version characteristic verification (function 250 )) that failed.
FIG. 3 is a process flow of a method of verifying the device driver 120 request according to embodiments of the invention. At block 310 , executing a test case 140 in the device driver 120 includes the device driver 120 being provided with information about the version of the data manipulation device to target. The version may be specified by the test case 140 itself or through initial communication between the device driver 120 and the simulation 140 (version verification portion 220 ). At block 320 , obtaining information related to the device driver 120 includes obtaining information from the software token and the internal memory of the device driver 120 as well as information in the request generated by the device driver 120 , as discussed with reference to functions of the version verification portion 220 above. Determining the device version, at block 330 , refers to the version specified in the request generated by the device driver 120 and is done as detailed with reference to function 230 above. At block 340 , the simulation 130 (version verification portion 220 of the simulation 130 ) determines if the version of the data manipulation device specified by the device driver 120 is the expected version of the data manipulation device. This process is executed using the cross verification discussed above with reference to function 240 . When it is determined (block 340 ) that the correct version of the data manipulation device is being targeted by the device driver 120 under test, verifying version-specific information at block 360 is performed by the version verification portion 220 of the simulator 130 . As noted above, the verification may include verifying formatting, for example. When the version specific information is verified, the version verification portion 220 of the simulation 130 calling the common simulation 130 (block 370 ) includes the version verification portion 220 initiating the data manipulation portion 260 of the simulation 130 . As noted above, the data manipulation portion 260 of the simulation 130 remains unchanged for the different versions for which the device driver 120 is tested.
When either the expected version of the data manipulation device is not requested by the device driver 120 (block 340 ) or the version-specific information in the request is not verified (block 360 ), returning an error message, at block 350 , can include the hardware specific or software specific codes discussed above. As an example, the hardware specific error codes might follow the format 0x0000zzzz, where zzzz represents the hardware error code. The software specific errors may be represented with 0xFFFFzzzz so that the hardware codes are distinguished from the software codes but fit within the same structure. Even in the event that existing test cases are not updated to recognize these new codes, the fact that the error codes fit into the existing structure allows the test case to still generically detect an error and perform general diagnostics.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one more other features, integers, steps, operations, element components, and/or groups thereof.
The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.
The flow diagrams depicted herein are just one example. There may be many variations to this diagram or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order or steps may be added, deleted or modified. All of these variations are considered a part of the claimed invention.
While the preferred embodiment to the invention had been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described. | A method, system, and computer program product are described. The system includes a first memory device to store programming code of the device driver, the device driver providing an interface to a data manipulation device, and a second memory device to store a test case to test the device driver, the device driver receiving version information specifying a targeted version or the device driver determining the version independently of the test case. The system also includes a third memory device to store a simulation including a version verification portion and a data manipulation portion, and a processor to execute the test case on the device driver, execution of the test case including, based on a request by the device driver, execution of the version verification portion of the simulation and, based on a result of executing the version verification portion, execution of the data manipulation portion of the simulation. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims the benefit of U.S. Provisional Patent Application No. 60/867,161, filed Nov. 24, 2006, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to centrifugal pumps. More particularly, the present invention relates to centrifugal pumps for fluids containing solids.
BACKGROUND OF THE INVENTION
[0003] During the drilling of a well, mud is circulated down hole to carry away drill cuttings. On the surface the mud is recirculated in different tanks using pumping units for delivering the mud to de-silter and de-sander.
[0004] Pumping of such fluids in a consistent manner can be difficult, which may make sample collection difficult and adversely affect readings or analysis of the samples.
SUMMARY OF THE INVENTION
[0005] A pump of the present invention may be used to deliver mud to a sample catcher, which benefits from a consistent flow for analytical measurement on drilling cuttings contained in the mud.
[0006] The present invention relates to an apparatus for pumping drilling mud with cuttings collected from active mud systems to the necessary height of reservoir. Specifically the pumping is performed in the field from possum belly (or mud box) to the sample catcher. The invention is providing the means for compact, portable and flow quantity adjustable pumping device for confined space as possum belly on the shale shaker.
[0007] In a first aspect, the present invention provides an apparatus for pumping drilling fluid containing drill cuttings having a reverse vane pump, a screw pump, a centrifugal pump, a drive shaft common with the reverse vane pump, the screw pump, and the centrifugal pump, the drive shaft adapted to be rotatably driven by a motor.
[0008] Preferably the screw pump includes helical auger. Preferably the reverse vane pump includes a blade impeller, the blade impeller having a plurality of radial blades. Preferably the blades are mounted at an angle forming a pitch. Preferably the pitch is between about 15° and about 75°. More preferably the pitch is between about 30° and about 60°. Most preferably the pitch is substantially 45°.
[0009] Preferably the centrifugal pump includes a horizontal centrifugal impeller. Preferably the horizontal centrifugal impeller comprising a substantially planar wing mounted to an radial arm. Preferably the radial arm includes a twisted wing mounted at an arm angle. Preferably the arm angle is between about 15° and about 75°. More preferably the arm angle is between about 30° and about 60°. Most preferably the arm angle is substantially 45°.
[0010] Preferably the apparatus includes a common housing, housing the reverse vane pump, the screw pump, and the centrifugal pump, the common housing having an upper portion proximate the centrifugal pump and a lower portion proximate the reverse vane pump. Preferably the upper portion comprising a window, the window adapted to allow air into the common housing. Preferably the lower portion includes a screen or guard, adapted to restrict the flow of larger objects into the apparatus.
[0011] Preferably the lower portion includes a screw pump inlet, the screw pump inlet having an opening through the lower portion of the common housing and extending along at least a portion of the screw pump. Preferably, an adjustable lift assembly for regulating the depth of submersion of the apparatus into the drilling fluid containing drill cuttings is provided.
[0012] Preferably the apparatus is powered by a drive means. Preferably the drive means includes an electric motor or a hydraulic motor, the hydraulic motor driven by pressurized hydraulic fluid from a hydraulic power pack.
[0013] In a further aspect, the present invention provides a method for pumping drilling fluid containing drill cuttings including providing air into the drilling fluid containing drill cuttings for decreasing the density of the drilling fluid containing drill cuttings.
[0014] Preferably the drilling fluid containing drill cuttings and air are agitated or otherwise blended or mixed or circulated.
[0015] Preferably pressurized air is injected into the drilling fluid containing drill cuttings.
[0016] Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Embodiments of the present invention will now be described, by way of example only, with reference to the attached Figures, wherein:
[0018] FIG. 1 is a general view of a centrifugal pump with screw pump accelerator and reverse vanes;
[0019] FIG. 2 is a top view of the centrifugal pump;
[0020] FIG. 3 is a detail view of the centrifugal pump along the section 3 - 3 of FIG. 2 ;
[0021] FIG. 4 is a detail view of the reverse vane pump; and
[0022] FIG. 5 is a detail view of the reverse vane pump along section 5 - 5 of FIG. 4 .
DETAILED DESCRIPTION
[0023] Referring to FIG. 1 , a centrifugal pump 1 . 1 of the present invention includes a centrifugal part 1 . 1 , a screw pump part 1 . 2 and a reverse vane pump part 1 . 9 . A motion axle or shaft 1 . 3 operably connects a centrifugal impeller (such as a flat 90-degree wing 1 . 6 or a twisted 45-degree wing 1 . 7 ) and a screw pump impeller (such as screw pump blades 1 . 5 ), corresponding to that disclosed in pending U.S. patent application Ser. No. 10/907,485 filed Apr. 2, 2005 which is incorporated herein by reference, along with a reverse vane impeller 1 . 95 . The motion axle or shaft 1 . 3 may be driven by common drive means such as an electric motor 1 . 4 .
[0024] An air inlet upper window 1 . 8 may be located proximate the centrifugal part 1 . 1 , for example generally at an upper portion of the centrifugal part 1 . 1 (as shown), the air inlet upper window 1 . 8 adapted to allow air to be drawn into the centrifugal part 1 . 1 in a controlled manner. The air inlet upper window 1 . 8 may be sized appropriately to allow a desired amount of air to be drawn into the casing, as would be known to one ordinarily skilled in the art. An optional screen or guard, such as ½ filter screen 3 . 0 (see FIG. 1 ), may be provided to restrict flow of larger drill cuttings or particles or other solids into the centrifugal pump. The reverse vane impeller 1 . 95 may chop, cut, or grind the pumped material to break up the material or reduce the size of lumps, chunks, drill cuttings, or particles. The reverse vane impeller 1 . 95 may clean or help clean the filter screen 3 . 0 . Preferably there is a gap between the bottom of the pump and the bottom of the screw pump blades 1 . 5 . Preferably the gap is between about 4″ (100 mm) and about 6″ (150 mm). Preferably there is a gap between the reverse vane impeller 1 . 95 and the screw pump blades 1 . 5 . The gap is preferably at least 4″ (100 mm) for a 2×6″ pump.
[0025] Referring to FIG. 2 , an outlet 2 . 1 is shown extending centrifugally from the centrifugal part 1 . 1 . The twisted 45-degree wings 1 . 7 may provide mixing of the pumped fluid and the inlet air, particularly when placed proximate the motion axle or drive shaft 1 . 3 (as shown in FIG. 1 ).
[0026] Referring to FIG. 4 , a reverse vane impeller 1 . 95 is shown as a plurality of vanes extending from the motion axle or shaft 1 . 3 . While shown as having two vanes or blades (e.g. like a propeller), one skilled in the art would recognize that any number of vanes (two or more) would be suitable. While shown as having an approximate reverse pitch of about 45°, one skilled in the art would recognize that pitch as only one example. The reverse vane impeller 1 . 95 is shown pitched down (when rotated clockwise from above—see FIG. 2 ). The reverse vane impeller 1 . 95 is adapted to cause at least a partial reverse flow, in the direction opposite to the flow imparted by the screw pump blades 1 . 5 (see FIG. 1 ). While shown ( FIG. 2 ) as being approximately 90° rotated relative to flat 90-degree wing 1 . 6 or twisted 45-degree wing 1 . 7 , one ordinarily skilled in the art would recognize the rotational orientation of the reverse vane impeller 1 . 95 may be anywhere between 0°-360°.
[0027] The liquid/drilling mud is pumped up by screw pump part 1 . 2 creating positive pressure for centrifugal pump. This positive pressurizing increases performance in 3 ways:
[0028] The mud level fluctuations that are very common on the drilling rigs are compensated by screw pump part 1 . 2 . Also by adjusting the level of pump one can adjust the quantity of mud pumping which is not possible with just a screw or centrifugal pump alone. The centrifugal pump 1 . 1 has to be submersed, this pumping is in full power, and no regulation and a screw pump part 1 . 2 is at full power, no regulation.
[0029] The airflow from the top opening ( 1 . 8 ) FIG. 1 allows air to mix with liquid/mud pumped creating air bubbles. Thus density of the mixture is decreased and the head pressure decreased. This will result in less power requirements and load on the motor.
[0030] Once the necessity of full airtight design is omitted the construction of the pump may be much lighter and cheaper to manufacture, which may significantly increase the ratio of power to size of the pump.
[0031] The above-described embodiments of the invention are intended to be examples only. Alterations, modifications and variations can be effected to the particular embodiments by those of skill in the art without departing from the scope of the invention, which is defined solely by the claims appended hereto. | Apparatus and method for centrifugal pump with screw pump accelerator and reverse vane impeller adapted for use in sample collection from drilling fluid containing drill cuttings. | 5 |
BACKGROUND OF THE INVENTION
The invention relates to a load torque lock, in particular for automotive applications, and to an apparatus, in particular an auxiliary and comfort apparatus, preferably for automotive applications, having a load torque lock.
Known from DE 197 53 106 C2 is a load torque lock which is incorporated in a drive train and which automatically blocks torques induced by the output drive when the drive is at a standstill. The torques induced from the drive side are transmitted in both directions. In order to block the torque on the output side a sling spring interacts frictionally with a brake component. The known load torque lock has proved effective. However, efforts are being made to make the load torque lock more robust, since deformations of the plastics material can occur, in particular in the contact region of the sling spring with the plastics carrier, which deformations are caused by surface pressures arising in operation and by relatively high bending stresses.
SUMMARY OF THE INVENTION
It is therefore the object of the invention to specify a robust load torque lock which has an increased service life. The load torque lock should preferably be inexpensive to produce and, further preferably, should be of lightweight construction. It is also the object of the invention to specify an apparatus having a correspondingly optimized load torque lock.
The invention is based on the concept of equipping the at least one contact region of the carrier, against which the sling element bears or is supported in the event of blocking, with means which bring about a reduction of the bending stress in the at least one contact region.
Especially preferred is an embodiment in which two contact regions of the carrier, which each interact with a respective free end of the sling element, are made at least partially of metal. By making the at least one contact region of the carrier at least partially of metal, inadmissible surface pressures and high bending stress can be avoided, whereby damage to the carrier when a torque to be blocked is induced can be reliably prevented.
A load torque lock configured according to the concept of the invention is especially suited to automotive applications such as sliding roof drives, seat adjusters, window regulators, windshield wiper drives, transmission and clutch actuators and electric steering systems, and for use in actuators generally. However, the application of a load torque lock configured according to the concept of the invention is not restricted hereto and can be used in principle in all motors, drives and machines.
Very especially preferred is an embodiment of the load torque lock in which the carrier coupled to the drive wheel, preferably by axial engagement, has a multi-part configuration, preferably such that it comprises a plastics main body to which at least one metal element is fixed to form at least one contact region. Very especially preferably, the carrier or main body is a plastics injection molding. The multi-part configuration of the carrier (plastics and metal protection) makes it possible to distribute the contact pressure on the sling element in such a manner that the main body of plastics material withstands the loadings and, overall, a system which can be produced at low cost is obtained.
With regard to the manner in which the at least one metal element is fixed to the plastics portion of the carrier, preferably to a main body of the carrier, there are various possibilities. For example, it is possible to inject a plastics injection molding compound partially around the metal element during the injection molding process and to fix the metal element in this way. In an alternative configuration, the metal element may be latched or clipped to the plastics portion and may subsequently be fastened thereto in a simple manner.
With regard to the configuration of the metal element there are also various possibilities. For example, it is possible to configure the metal element as a shell or as a pot closed on one side, in particular at the bottom, and to arrange the metal element in such a manner that it at least partially covers or encloses the plastics portion. It is also possible to configure the metal element in such a manner that the plastics material of the carrier is injected at least partially around the metal element.
Furthermore, there are also various possibilities with regard to the concrete configuration of the sling element. Especially preferred is an embodiment in which the sling element is in the form of an, in particular metal, sling spring, the sling spring preferably interacting, by means of two preferably inwardly bent, axially spaced free ends, with respective metal contact regions of the carrier. Alternative embodiments of the sling element are also possible, for example as a sling link chain, a sling strap, a sling cable or the like. The sling element is preferably arranged in such a manner that its free ends can be moved towards and away from one another in the circumferential direction in order to bring the sling element frictionally into frictional engagement with the brake component on the radially inner side or the radially outer side in the event of blocking.
There are also various possibilities with regard to the configuration of the brake component. It is especially preferred if the brake component has a cylindrical friction surface (inner or outer cylindrical surface), it being possible to implement both an embodiment in which the sling element interacts with the inner circumference of the brake component, that is, with a friction surface formed on the inner circumference, and an embodiment in which the sling element surrounds the brake component and in this case interacts frictionally by frictional engagement with an outer circumference of the brake component in the event of blocking.
The invention also leads to an apparatus, preferably an auxiliary or comfort apparatus, in particular for automotive applications. The apparatus may be, for example, a motor and/or a machine. Very especially preferably, it is an actuating drive, such as a sliding roof drive, a window regulator drive, a seat adjuster drive, a windshield wiper drive or a transmission and/or clutch actuator. It may also apply to an electric steering system for motor vehicles, etc. The apparatus is distinguished in that it is provided with at least one load torque lock configured according to the concept of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages, features and details of the invention are apparent from the following description of preferred exemplary embodiments and with reference to the drawings, in which:
FIG. 1 shows in a perspective, partly sectional representation a possible embodiment of a load torque lock (locking coupling),
FIG. 2 is an exploded representation of a carrier consisting of a plastics main body and two clip-on metal elements,
FIG. 3 is a side view of a fully assembled carrier,
FIG. 4 is a side view of the assembled carrier rotated through 180° in relation to FIG. 3 ,
FIG. 5 shows a part of the load torque lock in a partially sectional perspective view with a modified metal element,
FIG. 6 shows the metal element according to FIG. 5 in a perspective view,
FIG. 7 shows a modified carrier in a perspective view,
FIG. 8 shows the carrier according to FIG. 7 with an additional metal element, also in a perspective view,
FIG. 9 shows a further modified metal element with a support section in a perspective representation,
FIG. 10 shows the metal element according to FIG. 10 when installed on the carrier, in a perspective view,
FIG. 11 shows a further modified metal element with a support section in a perspective representation,
FIG. 12 shows the metal element according to FIG. 11 when installed on the carrier, in a perspective view,
FIG. 13 shows a further modified metal element with a support section in a perspective representation, and
FIG. 14 shows a metal element according to FIG. 13 when installed on the carrier, in a perspective view.
DETAILED DESCRIPTION
In the figures, identical elements and elements having the same function are designated by the same reference numerals.
FIG. 1 shows a possible embodiment of a permanently coupled, that is, non-disengageable load torque lock 1 . This includes a sling element 12 in the form of a metal sling spring. The sling element 12 is received in a hollow-cylindrical brake component 13 and, in the event of blocking, interacts by means of its outer circumference with the inner circumferential surface of the brake component 13 . In an alternative variant, which is known per se and is not represented, the sling element 12 interacts by means of its inner circumference with the preferably cylindrical outer circumference of a brake component.
The load torque lock 1 includes a drive wheel 14 in the form of a worm gear which is drivable in both directions of rotation by an electric-motor driven transmission worm (not shown). The drive wheel 14 is coupled to a carrier 15 which engages in the axial direction in receiving pockets 16 of the drive wheel 14 . The carrier 15 serves in its turn to transmit the torque induced on the drive side to an adjusting mechanism, for example a cable control mechanism of a window regulator drive.
The sling element 12 has two free ends spaced from one another in the axial direction, of which only an upper, radially inwardly bent free end 17 is shown in FIG. 1 . The drive wheel 14 interacts with the carrier 15 in such a way that if a torque is induced on the drive side, that is, by the drive wheel 14 , it is transmitted to the carrier 15 . The sling element 12 is then entrained, that is, it is displaced together with the drive wheel 14 and the carrier 15 relative to the fixed brake component 13 . In the event that torque is induced on the output side, that is, via the carrier 15 , the free ends 17 of the sling element 12 are moved apart in such a manner that the outer circumference of the sling element 12 is increased, whereby the sling element 12 interacts frictionally by means of its outer circumference with the inner circumference of the brake component 13 , and thus blocks the torque induced on the output side, which torque, therefore, is not transmitted to the drive wheel 14 and thus in the direction of a drive motor, in particular of an electric motor (not shown).
In a variant (not shown) of a load torque lock 1 in which the sling element 12 interacts with an outer circumference of a brake component 13 , the free ends 17 must be moved with respect to one another as described previously, but in the reverse direction, in order to produce the braking effect.
In order to increase the robustness of the load torque lock 1 , a metal element 20 is provided on each axial projection 18 (only one is shown) by means of which the carrier 15 engages axially in the receiving pockets 16 , against which metal element 20 a respective free end 17 of the sling element 12 bears in order to block the torque induced on the output side.
In the following description a first preferred embodiment of the multi-part carrier 15 is explained in detail with reference to the perspective representations in FIG. 2 to FIG. 4 .
FIG. 2 shows in a perspective representation the carrier 15 of multi-part construction. This carrier 15 includes a main body 22 of plastics material produced as an injection molding. In an upper portion the main body 22 is provided with an external toothing 23 in order to transmit, for example to a cable control mechanism, the torque transmitted by the drive wheel 14 (see FIG. 1 ) to the carrier 15 .
The carrier 15 , more precisely the main body 22 , has two peg-like projections 18 spaced from one another by 180° in the circumferential direction, which serve to transmit torque, on the one hand imparting a torque induced on the output side to the sling element 12 as shown in FIG. 1 and, on the other, receiving a torque induced on the drive side via the drive wheel 14 (see FIG. 1 ).
The carrier 15 further includes two clip-on metal elements 20 to be fixed to the projections 18 for the purpose of increasing the robustness of the multi-part carrier 15 . Contrary to the prior art, the free ends 17 of the sling element 12 do not bear directly on the projections 18 , but only indirectly thereon via the metal elements 20 , which interact immediately, that is, directly, with the free ends 17 of the sling element 12 .
In FIG. 3 and FIG. 4 the carrier 15 is in each case represented in the fully assembled state. It can be seen that the metal elements 20 are arranged offset to one another in the axial direction. This is explained by the fact that the free ends 17 of the sling element 12 , in the form of a sling spring, are also spaced from one another in the axial direction.
The metal elements 20 each encompass a plastics portion 24 of the main body 22 formed by a respective portion of the projection.
As is apparent from FIG. 4 , the metal elements 20 on a common side each form a contact region 25 for direct abutment against a respective free end 17 of the sling element 12 . In this way inadmissible surface pressures, of the kind which might occur in the event of blocking with purely plastics projections 18 , can be reliably avoided. Furthermore, the metal elements 20 reduce the bending stresses in the projections 18 , in that the forces exerted by the free ends 17 are imparted over a larger area to the projections 18 .
FIGS. 5 and 6 show a modified metal element 20 a . The metal element 20 a has a plate-like middle region 27 with a through-opening 28 . The metal element 20 a is mounted on a drive pin 30 of the carrier 15 by means of the through-opening 28 . The middle region 27 is arranged in a plane below the carrier 15 and its projections 18 . Two contact sections 31 arranged offset to one another by 180° project from the outer portions of the middle region 27 in the direction of the projections 18 , the two contact sections 31 being configured to have different lengths corresponding to the different axial arrangement of the two free ends 17 of the sling element 12 . In this case the contact sections 31 are arranged between the free ends 17 and the projections 18 , in the receiving pockets 16 of the carrier.
FIG. 7 shows a modified carrier 15 a . The carrier 15 a has means for reducing the bending stresses resulting from the forces induced by the free ends 17 of the sling element 12 in the carrier 15 a . These means consist in a particular geometrical configuration of the carrier 15 a.
To this effect the carrier 15 a has a modified projection 18 a which, viewed in a plane transverse to the longitudinal direction of the carrier 15 a , occupies an angular range of at least 10°, in particular from 30° to 120°, and up to the approximately 180° illustrated. In this case the angular range referred to is arrived at according to the stress or the forces to be transmitted and, inter alia, as a function of the material used. What is essential to the carrier 15 a is that the two end faces 33 , 34 delimiting the projection 18 a serve as mating or abutment faces for the two free ends 17 of the sling element 12 . As a result of the usually wider configuration of the projection 18 a as compared to the projections 18 , in particular the bending stress of the projection 18 a on the base 35 of the carrier 15 a is reduced. In addition, it may preferably be provided for this purpose that a radius 36 is formed at least in the respective transitional regions between the base 35 and the end faces 33 , 34 , which radius 36 further reduces the bending stress or the notch effect.
FIG. 8 shows the carrier 15 a interacting additionally with a metal element 20 b which corresponds substantially to the metal element 20 represented in FIGS. 2 to 4 .
FIGS. 9 and 10 show a modified metal element 20 c for use on the carrier 15 a (alternatively, an insert on the carrier 15 is also possible for this purpose). In this case the metal element 20 c has an additional support section 38 which passes through an opening 39 formed in the carrier 15 a and rests against the underside 40 of the carrier 15 a . A bending moment transmitted by the free end 17 of the sling element 12 is thereby transmitted via the support section 38 to the carrier 15 a , at least partially unloading the projection 18 a.
FIGS. 11 and 12 show a modified metal element 20 d for use on the carrier 15 . In this case the metal element 20 d has an arched configuration and encompasses the projection 18 of the carrier 15 . In addition, the metal element 20 d has on the side opposite the contact region 25 a support section 38 d which rests against the upper side 41 of the carrier 15 .
The modified metal element 20 e for the carrier 15 shown in FIGS. 13 and 14 represents a combination of the metal elements 20 c and 20 d . To this end the metal element 20 e has two support regions 43 , 44 arranged on opposite sides, which interact with the upper and lower sides of the carrier 15 respectively.
It will be mentioned additionally that the metal elements 20 , 20 a to 20 e are produced, in particular, from sheet metal as punched and bent parts. Furthermore, it may be provided in the case of the metal elements 20 c , 20 d , 20 e that the support sections 38 , 38 d , 43 , 44 are also enclosed by the plastics material of the carrier 15 , 15 a . The metal elements 20 c , 20 d , 20 e are thereby additionally anchored in the carrier 15 , 15 a , so that additional measures for retaining them on the carrier 15 , 15 a may optionally be dispensed with. | The invention relates to a load torque lock ( 1 ) comprising a sling element ( 12 ) that frictionally interacts with a brake component ( 13 ) for blocking a torque, and a drive wheel ( 14 ) that is coupled in a torque transferring manner to a carrier ( 15; 15 a ) having at least one contact area ( 25 ) to the sling element ( 12 ) and engaging axially in the drive wheel ( 14 ), by means of which a torque to be blocked can be initiated in the sling element ( 12 ). According to the invention, the carrier ( 15; 15 a ) has means for reducing the bending tension in the at least one contact region ( 25 ). | 4 |
BACKGROUND OF THE INVENTION
This invention relates to an elastomer of copolymer made up of a vinyl carboxylate, ethylene, an alkyl acrylate and/or an alkoxyalkyl acrylate, and a monoalkoxyalkyl maleate. This invention also relates to vulcanized products of said elastomer.
Heretofore, there have been provided elastomer compositions containing a copolymer made up of a vinyl carboxylate, ethylene, an alkyl acrylate and/or an alkoxyalkyl acrylate, and a monoepoxy monoolefinic compound (e.g. glycidyl methacrylate) as a cure site monomer (cf. U.S. Pat. No. 4,303,560 corresponding to Japanese Patent Kokai Koho Nos. 55-123641 and 55-123611.)
These elastomer compositions can be vulcanized by using a vulcanizing agent such as an aliphatic acid soap/sulfur, polyamines, a carboxylic acid or ammonium salts thereof, and the vulcanized products are improved in the heat resistance, oil resistance and weatherproof as well as mechanical properties. The compositions, however, have unnegligible problems in their curing rate.
That is to say, they often require post cure after the usual vulcanization whereby covering their low curing rate and obtaining a product of desired properties. The post cure, in fact, enables the vulcanized product to have an improved compression set. If the post cure step, however, can be performed in a shorter time or utterly omitted, the vulcanized products may be manufactured more advantageously in a commercial scale. Therefore, elastomers having good vulcanizate properties have long been expected.
Heretofore, there have been reported many studies on new copolymer elastomers and vulcanizing agents therefor to attain more rapid and more effective vulcanizing procedure. For example, U.S. Pat. No. 3,883,472 discloses the fact that faster cures may be attained by using compositions containing elastomeric copolymer made up of an acrylate, ethylene, and a monoester of butenedionic acid. These elastomers of acrylic ester type copolymer using the monoester of butenedionic acid (e.g. monoalkyl maleates) as a cure site monomer have, in fact, faster curing rate. However, they have disadvantageous tendency of scorching (a phenomenon of an early-time vulcanization).
SUMMARY OF THE INVENTION
It is an object of this invention to provide an elastomer of acrylic ester type copolymer exhibiting well accelerated curing rate without tendency of scorching, requiring no post cure or shortened post cure time and having good processability and storage stabilities.
In accordance with this invention, there is provided an elastomer of acrylic ester type copolymer made up of a monomeric composition comprising; 100 parts by weight of a mixture of the following three components, (A) 0-50% by weight of a vinyl carboxylate of the formula, R 1 COOCH═CH 2 wherein R 1 is an alkyl group having 1 to 4 carbon atoms, (B) 0-30% by weight of ethylene and (C) 10-100% by weight of an alkyl acrylate of the formula, CH 2 ═CHCOOR 2 wherein R 2 is an alkyl group having 1 to 8 carbon atoms and/or an alkoxyalkyl acrylate of the formula, CH 2 ═CHCOOR 3 OR 4 wherein R 3 is an alkylene group having 1 to 4 carbon atoms and R 4 is an alkyl group having 1 to 4 carbon atoms; and 2-15 parts by weight of (D) a monoalkoxyalkyl maleate of the formula, ##STR1## wherein R 5 is an alkylene group having 1 to 4 carbon atoms and R 6 is an alkyl group having 1 to 4 carbon atoms.
There is also provided a vulcanized product made of the above-mentioned elastomer of acrylic ester type copolymer and improved in the mechanical properties, oil resistance, heat resistance and weatherproof.
DETAILED DESCRIPTION OF THE INVENTION
The vinyl carboxylates used as component (A) are those represented by the above formula and may be exemplified by vinyl acetate and vinyl propionate. When the carboxylate has higher alkyl group, the elastomer obtained becomes unsatisfactory in its oil resistance. In this point of view, vinyl acetate is preferably used as the component (A). If the content of vinyl carboxylate in the mixture of (A), (B) and (C) surpasses 50% by weight, the elastomer becomes unsatisfactory in its low-temperature flexibility. The content of vinyl carboxylate is preferably 0 to 40% by weight, more preferably 0 to 30% by weight.
On the other hand, the amount of ethylene used as component (B) is within the range of 0 to 30% by weight in the mixture of (A), (B) and (C). When the content of ethylene surpasses 30% by weight, the elastomer becomes unsatisfactory in its oil resistance. The content is preferably 0 to 25% by weight, more preferably 0 to 20% by weight.
The component (C), alkyl acrylate and alkoxyalkyl acrylate may be used alone or in combination in an amount of 10 to 100% by weight based on the mixture of (A), (B) and (C). When the alkyl acrylate and alkoxyalkyl acrylate are used in combination, the elastomer composition obtained may have well balanced oil resistance and low-temperature flexibility.
Illustrative examples of the alkyl acrylate are methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate and n-octyl acrylate.
Illustrative examples of the alkoxyalkyl acrylate are methoxymethyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate and ethoxypropyl acrylate.
The monoalkoxyalkyl maleates used as component (D) are those represented by the above-illustrated formula. Illustrative examples thereof are monomethoxyethyl maleate, monoethoxyethyl maleate, monobutoxyethyl maleate and monomethoxybutyl maleate. The amount of the component (D) used is between 2 and 15 parts by weight per 100 parts of the mixture of (A), (B) and (C).
The monoalkoxyalkyl maleate gives cure sites to the copolymer according to this invention so as to make the vulcanization by a polyfunctional compound (e.g., polyamines) possible and gives good curing rate to the copolymer. When the amount of component (D) is less than 2 parts by weight, sufficient cure sites cannot be formed so that the mechanical strength and compression set of the elastomer get worse. When the amount of compound (D) surpasses 15 parts by weight, the crosslinking density is so tight that good mechanical strength cannot be obtained.
The copolymer according to this invention can be prepared by copolymerizing the above-mentioned monomeric composition of (A) through (D). The copolymerization may be carried out by conventional methods such as emulsion polymerization, suspension polymerization, solution polymerization and bulk polymerization, under the usual conditions. Among these methods, emulsion polymerization is preferably used for the reason that the polymerization rate of monomers is high and high molecular weight polymers can be obtained. Polymerization may be carried out in a batch process or in such a process that monomers are continuously or intermittently added during the operation. Polymerization temperature may be selected from the range of 5° to 80° C., preferably 30°-70° C.
The polymerization reaction may be started using a radical initiator. Illustrative examples of the radical initiator are organic peroxides or hydroperoxides, such as benzoyl peroxide, dicumyl peroxide, t-butyl hydroperoxide, a combination thereof with a Redox type initiator; diazo compounds such as azobisisobutylonitrile; persulfates such as sodium, potassium and ammonium persulfates and a combination thereof with a Redox type initiator.
Representative examples of the emulsifier to be used are anionic, cationic and nonionic surfactants well-known in the art. The reaction of the emulsion polymerization may be carried out by mixing water buffered with inorganic salts and monomers and starting the reaction by use of the radical initiator.
Usually the polymerization is performed till 90% of the monomers react. The thus prepared latex is then coagulated to separate polymeric products. Representative methods for coagulating are coagulation using metal salts such as CaCl 2 , MgSO 4 , Al(OH) 3 , Na 2 SO 4 and (NH 4 ) 2 SO 4 or boron compound such as borax and boric acid, thermal coagulation and freeze coagulation. Thereafter, the thus obtained copolymer is sufficiently washed with water and dried.
The elastomer of copolymers thus obtained has, preferably a Mooney viscosity (ML 1+4 ) between 30 and 70 at 100° C. as measured by Mooney Viscometer produced by Shimadzu Corporation.
The thus obtained elastomer of copolymer is compounded while adding various additives which are used in the usual rubber compounding and vulcanized and molded to give the desired rubber products.
The vulcanization is carried out by use of vulcanizing agents in an amount of 0.3-5, preferably 0.5-3 parts by weight per 100 parts by weight of the elastomer. When the amount of the vulcanizing agent used is less than 0.3 parts by weight, the vulcanization reaction cannot be sufficiently performed. When the amount surpasses 5 parts by weight, the overcure takes place.
Preferable examples of the vulcanizing agent are aliphatic and aromatic primary amines. Illustrative examples of the aliphatic primary amine are hexamethylenediamine, hexamethylenediamine carbamate and tetramethylenepentamine. Illustrative examples of the aromatic primary amine are 4,4'-methylenedianiline, 4,4'-oxyphenyldiphenylamine and 4,4'-methylenebis(o-chloroaniline). Preferable vulcanizing agents are hexamethylene carbamate and 4,4'-methylenedianiline.
Illustrative examples of a vulcanization accelerator to be optionally admixed with the elastomer of copolymers are guanidines such as guanidine, tetramethylguanidine, dibutylguanidine, diphenylguanidine and diorthotolylguanidine.
In addition, fillers such as carbon black, silica and surface-treated calcium carbonate are used in an amount of 10-200 parts by weight, preferably 30-100 parts by weight per 100 parts of the elastomer, so as to make the rubber products exhibit the desired practical properties.
A lubricant such as stearic acid, its metal salts and amines (e.g. stearyl amine) is used to adjust the processability and other properties of the composition and, in fact, is improved in processability of two-roll mill.
In addition, the plasticizers and antioxidants may be used.
Illustrative examples of the plasticizers are dialkyl and diallyl organic esters such as diisobutyl, diisooctyl and dibenzyl esters of sebacic acid, azelaic acid and phthalic acid.
Illustrative examples of the antioxidant are amine type antioxidants such as N-phenyl-N'-isopropyl-p-phenylenediamine and phenyl-α-naphthylamine; phenol type antioxidants such as 3,5-di-t-butyl-4-hydroxy toluene, 1,3,5-trimethyl2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzene), octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate and 4,4'-thiobis(6-t-butyl-3-methylphenol) and the like; dithionic acid type antioxidants such as nickel dibutyl dithiocarbamate and dilauryl dithiopropionate; and phosphate type antioxidants such as tris(nonylphenyl)phosphite. These antioxidants may be used alone or in combination thereof. The amount of the antioxidant is 0.5-3 parts by weight, preferably 1 part by weight per 100 parts of the elastomer.
The addition of the above-mentioned additives to the elastomer may be carried out by the conventional compounding procedure as used in the rubber industry.
The elastomers are cured at a temperature from about 120° C. to about 200° C., preferably from about 150° C. to about 180° C. The vulcanization time may be shortened if the vulcanization temperature is elevated and usually determined from the range between 2 and 120 minutes. The curing can be performed in 20 minutes at 170° C. The optional post cure at 150°-200° C. for about 2 to 4 hours may result in well improved compression set.
The thus obtained elastomer composition may be molded by conventional molding methods to give rubber products suitable for uses in which good mechanical properties as well as the good oil resistance, heat resistance and weatherproof are required. The rubber products according to this invention may be used for rubber elements of automotive vehicles and the like such as elements usually contacting with high temperature lubricant oil, such as an oil cooler hose of the powertrain section, oil cooler hose of the stearing section, oilpangasket, O-ring, oilseal, packings, fuel hose and airduct hose; exhaust hose of high temperature drier which usually contacts with high temperature air; and the rubber elements used in the field which usually contact with high temperature lubricant oil.
This invention will be illustrated by the following non-limitative Examples.
EXAMPLE 1
The polymer of vinyl acetate, ethylene, n-butyl acrylate, ethyl acrylate and monomethoxyethyl maleate, was prepared by the conventional method of emulsion polymerization using the following formulation:
______________________________________Water 43.2 kgVinyl acetate 7.2 kgEthyl acrylate 11.5 kgn-Butyl acrylate 10.1 kgEthylene 5.2 kgMonomethoxyethyl maleate 2.0 kgPartially saponified polyvinyl alcohol 1.4 kgSFS.sup.1 86.4 gTartaric acid 8.64 gMohr's salt.sup.2 4.32 gSodium acetate 57.6 gPeroxide.sup.3 1.70 l______________________________________ Remarks: .sup.1 Sodium formaldehyde sulfoxalate .sup.2 Iron (II) ammonium sulfate .sup.3 0.5% Aqueous solution of tbutylhydroperoxide
To a 130 l-volume autoclave were charged 1.4 kg of polyvinylalcohol (hereinunder referred to as PVA), 86.4 g of SFS, 8.64 g of tartaric acid, 4.32 g of Mohr's salt and 57.6 g of sodium acetate which were previously dissolved in 43.2 kg of water. Thereafter, 7.2 kg of vinyl acetate and 1.35 kg of monomethoxyethyl maleate were added and emulsified under stirring. the inside atmosphere of the autoclave was then perfectly replaced with nitrogen gas and 5.2 kg as weighed of ethylene gas was introduced under pressure thereinto. After the reaction temperature was raised to 55° C., a mixture of 11.5 kg of ethyl acrylate, 10.1 kg of n-butyl acrylate and 650 g of monomethoxyethyl maleate as well as a 0.5% aqueous solution of peroxide (t-butylhydroperoxide) were separately added to the reaction mixture over 6 to 10 hours by using the respective inlet port and the polymerization was further proceeded.
The resulting emulsion was coagulated by adding a 10% aqueous solution of (NH 4 ) 2 SO 4 . The isolated polymer was fully washed with water and dried.
The thus obtained elastomer was compounded in accordance with the below-mentioned recipe by using a 6-in. two-roll mill heated to 40° C. and thereafter subjected to press cure at 170° C. for 20 minutes to obtain a 15 cm square sheet of 2 mm in thickness. The properties of the rubber sheet were measured and the results are shown in Table 1.
______________________________________Rubber Recipe (parts by weight)______________________________________Rubber 100Antioxidant 2(Tris-(nonylphenyl)phosphite)Stearic acid 1Carbon black HAF 404,4'-Methylenedianiline 1Diphenylguanidine 2______________________________________
EXAMPLES 2 TO 6
A series of the polymerization procedures was carried out in the same manner as in Example 1, with the exception that the amounts of vinyl acetate, methyl acrylate, ethyl acrylate, n-butyl acrylate and methoxyethyl acrylate were changed as shown in Table 1. The results are shown in Table 1.
Remarks: Measurement methods of the physical properties shown in Table 1 and other Tables mentioned below are as follows:
*1 Mechanical properties: JIS K 6301
T B : Tensile strength
E B : Elongation
H S : Hardness measured by JIS Spring Type Hardness Tester A Type
*2 Heat resistance: JIS 6301 6.3 for samples subjected to heat-aging at 150° C. for 96 hours.
A R (T B ): The ratio of residual T B value measured after the heat-aging based on T B value measured before the heating.
A R (E B ): The ratio of residual E B value measured after the heat-aging based on E B value measured before the heating.
ΔH S : The difference between H S value measured after the heat-aging and H S value measured before the heating.
*3 Compression set: JIS 6301-10 measuring the ratio of residual strain after heat-compression at 150° C. for 70 hours.
*4 Oil resistance: JIS 6301
ΔV: The ratio (%) of volume increase after soaking into a JIS No. 3 oil at 150° C. for 96 hours.
*5 Low-temperature flexibility: JIS K 6301-19
T 100 : The temperature at which the modulus angular is 100 times as much as that measured at 23±3° C.
*6 Scorching time: The period in which the compound Mooney increases by 5 points based on the lowest value thereof measured at 125° C. by use of the L-rotor of Mooney viscometer.
EXAMPLES 7 AND 8
A series of the polymerization procedures was carried out in the same manner as in Example 1 using the same reactor, with the exception that ethyl acrylate, n-butyl acrylate and methoxyethyl acrylate were used in the quantities as shown in Table 2 and that the total of the monomers were fed to the reactor at the beginning of the polymerization. The results are shown in Table 2.
EXAMPLE 9
A series of the polymerization procedures was carried out in the same manner as in Example 1, with the exception that ethylene was not used. The results are shown in Table 2.
TABLE 1__________________________________________________________________________ Example 1 Example 2 Example 3 Example 4 Example 5 Example 6__________________________________________________________________________Feed Composition(parts by weight)Vinyl acetate 20 30 25 15 25 20Methyl acrylate 10Ethyl acrylate 35 30n-Butyl acrylate 30 20 30 60 55Methoxyethyl acrylate 30 70Ethylene 15 20 15 15 15 15Monomethoxyethyl maleate 7 7 7 7 7 7Properties*.sup.1T.sub.B (kg/cm.sup.2) 149 180 130 140 125 145E.sub.B (%) 270 310 290 380 250 300H.sub.S 60 68 62 55 58 60Heat resistance*.sup.2A.sub.R (T.sub.B) % 95 96 92 93 97 98A.sub.R (E.sub.B) % 85 93 88 87 89 90ΔH.sub.S +10 +11 +12 +12 +10 +8Compression set*.sup.3 (%) 34 32 31 41 42 40Oil resistance*.sup.4 31 21 24 6 58 50ΔV (%)Low-temp. flexibility*.sup.5 -24 -15 -27 -31 -31 -25T.sub.100 (°C.)Scorching time*.sup.6 10 min. 10 min. 10 min. 12 min. 12 min. 12 min.(ts) 20 sec. 40 sec. 15 sec. 30 sec.__________________________________________________________________________
TABLE 2______________________________________ Example 7 Example 8 Example 9______________________________________Feed Composition(parts by weight)Vinyl acetate 20Ethyl acrylate 100 50 40n-Butyl acrylate 25 40Methoxyethyl acrylate 25Monomethoxyethyl 7.0 7.0 7.0maleatePropertiesT.sub.B (kg/cm.sup.2) 146 152 135E.sub.B (%) 280 310 280H.sub.S 63 63 62Heat resistanceA.sub.R (T.sub.B) 85 85 94A.sub.R (E.sub.B) 80 88 85ΔH.sub.S +14 +16 +12Compression set 46 40 35Oil resistance 15 20 28ΔVLow-temp. flex. -15 -26 -20T.sub.100Scorching time 11 min. 10 min. 9 min. 15 sec. 30 sec.______________________________________
COMPARATIVE EXAMPLES 1 THROUGH 6
The polymerization procedures were carried out by using glycidyl methacrylate instead of the monoalkoxyalkyl maleates used in Examples 1 through 9.
To a 130 l-volume autoclave were charged 1.4 g of PVA, 86.4 g of SFS, 2.88 g of ethylenediaminetetraacetic acid (hereinunder referred to as EDTA), 1.44 g of Fe(II)SO 4 and 57.6 g of sodium acetate which were previously dissolved in 43.2 kg of water. Thereafter, 7.2 kg of vinyl acetate and 72 g of glycidyl methacrylate (hereinafter referred to as GMA) were added and emulsified under stirring. The inside atmosphere of the autoclave was then perfectly replaced with nitrogen gas and 5.2 kg as weighed of ethylene gas was introduced thereinto under pressure.
After the reaction temperature was raised to 55° C., a mixture of 11.5 kg of ethyl acrylate, 10.1 kg of n-butyl acrylate and 360 g of GMA as well as a 0.5% aqueous solution of ammonium persulfate were separately added to the reaction mixture over 6 to 10 hours by use of the respective inlet ports and the polymerization was further proceeded.
The resulting emulsion was coagulated by adding a 2.5% aqueous solution of borax. The isolated polymer was fully washed with water and dried.
The thus obtained elastomer was compounded in accordance with the below-mentioned recipe by means of a 6-in. two-roll mill heated to 40° C., and thereafter subjected to press vulcanization at 170° C. for 20 minutes to obtain a 15 cm square sheet of 2 mm in thickness. The properties of the rubber sheet were measured and the results are shown in Table 3.
______________________________________Rubber Recipe (parts by weight)______________________________________Rubber 100Antioxidant (nickel dibutyl 1dithiocarbamate)Stearic acid 1Carbon black HAF 40Hexahydrogenated Phthalic anhydride 0.52-methylimidazole 0.2______________________________________
TABLE 3__________________________________________________________________________ Comparative Comparative Comparative Comparative Comparative Comparative Example 1 Example 2 Example 3 Example 4 Example 5 Example 6__________________________________________________________________________Feed Composition(parts by weight)Vinyl acetate 20 30 25 15 25 20Methyl acrylate 10Ethyl acrylate 35 30n-Butyl acrylate 30 20 30 60 55Methoxyethyl acrylate 30 70Ethylene 15 20 15 15 15 15Glycidyl methacrylate 1.5 1.5 1.5 1.5 1.5 1.5PropertiesT.sub.B 113 123 103 91 99 108E.sub.B 710 600 510 620 550 630H.sub.S 57 70 56 45 48 54Heat resistanceA.sub.R (T.sub.B) 132 141 129 149 126 137A.sub.R (E.sub.B) 41 53 57 63 51 49ΔH.sub.S +17 +14 +16 +17 +22 +17Compression set (%) 86 82 78 90 86 82Oil resistance 31 21 24 6 58 50ΔV (%)Low-temp. flex. -24 -15 -27 -31 -31 -25T.sub.100 (° C.)Scorching time 11 min. 11 min. 13 min. 19 min. 12 min. 12 min.(ts) 40 sec. 40 sec. 15 sec. 20 sec.__________________________________________________________________________
COMPARATIVE EXAMPLES 7 AND 8
A series of the polymerization procedures was carried out in the same manner as in Comparative Example 1 using the same reactor, with the exception that ethyl acrylate, n-butyl acrylate and methoxyethyl acrylate were used in the amounts as shown in Table 4, and that the total of the monomers were fed to the reactor at the beginning of the polymerization. The results are shown in Table 4.
COMPARATIVE EXAMPLE 9
A series of the polymerization procedures were carried out in the same manner as in Comparative Example 1, with the exception that ethylene was not used. The results are shown in Table 4.
EXAMPLES 10 THROUGH 12
A series of the polymerization procedures was carried out in the same manner as in Example 1, with the exception that the monoalkoxyalkyl group of the monoalkoxyalkyl maleate used was replaced with the respective groups as shown in Table 5. The results are shown in Table 5.
COMPARATIVE EXAMPLE 10 THROUGH 13
A series of the polymerization procedures was carried out in the same manner as in Example 5, with the exception that the monoalkoxyalkyl group of the monoalkoxyalkyl maleate used was replaced with the respective groups as shown in Table 5. The results were shown in Table 5.
COMPARATIVE EXAMPLES 14 AND 15, EXAMPLES 13 AND 14
A series of the polymerization procedures was carried out in the same manner as in Example 1, with the exception that the amount of monomethoxyethyl maleate was changed as shown in Table 5.
TABLE 4______________________________________ Comparative Comparative Comparative Example 7 Example 8 Example 9______________________________________Feed Composition(parts by weight)Vinyl acetate 20Ethyl acrylate 100 50 40n-Butyl acrylate 25 40Ethoxyethyl 25acrylateGlycidyl 1.5 1.5 1.5methacrylatePropertiesT.sub.B 133 72 100E.sub.B 510 790 640H.sub.S 52 38 50Heat resistanceA.sub.R (T.sub.B) 121 206 141A.sub.R (E.sub.B) 60 44 50ΔH.sub.S +14 +23 +12Compression set 96 92 94Oil resistance 15 20 31Low-temp. flex. -15 -26 -20Scorching time 7 min. 9 min. 10 min. 20 sec. 15 sec.______________________________________
TABLE 5__________________________________________________________________________ Example Example Example Comparative Comparative Comparative Comparative 10 11 12 Example 10 Example 11 Example 12 Example__________________________________________________________________________ 13Feed Composition(parts by weight)Vinyl acetate 25 25 25 25 25 25 25n-Butyl acrylate 60 60 60 60 60 60 60Ethylene 15 15 15 15 15 15 15Monoethoxyethyl maleate 7Monbutoxyethyl maleate 7Monomethoxybutyl maleate 7Monomethyl maleate 7Monoethyl maleate 7Monobutyl maleate 7Mono 2-ethylhexyl maleate 7PropertiesT.sub.B 113 98 123 118 103 102 114E.sub.B 220 240 240 250 250 230 220H.sub.S 60 56 63 64 61 60 64Heat resistanceA.sub.R (T.sub.B) % 105 97 87 87 93 95 87A.sub.R (E.sub.B) 83 88 70 84 88 74 70ΔH.sub.S +12 +11 +11 +8 +10 +16 +18Compression set 41 42 41 46 48 48 57Scorching time 9 min. 10 min. 9 min. 5 min. 6 min. 3 min. 5 min. 30 sec. 15 sec. 15 sec. 5 sec. 50 sec. 30 sec.__________________________________________________________________________
EXAMPLES 15 AND 16
A series of the polymerization procedures was carried out in the same manner as in Example 1, with the exception that DDM (methylenedianiline) and HMDAC (hexamethylenediamine carbamate) were used as the vulcanizing agent and accelerator, respectively.
EXAMPLES 17 AND 18
A series of the polymerization procedures was carried out in the same manner as in Example 1, with the exception that the press cure and the post cure were carried out in the manner as shown in the remarks in Table 7.
TABLE 6______________________________________ Comparative Comparative Example Example Example 14 Example 15 13 14______________________________________FeedComposition(parts byweight)Vinyl acetate 20 20 20 20Ethyl 35 35 35 35acrylaten-Butyl 30 30 30 30acrylateEthylene 15 15 15 15Monometh- 1 20 4 12oxyethylmaleateVulcanizingagentsDDM 2 1 2 1Diphenyl- 4 2 4 2guanidinePropertiesT.sub.B (kg/cm.sup.2) 61 175 105 168E.sub.B (%) 820 120 400 150H.sub.S 46 77 50 74HeatresistanceA.sub.R (T.sub.B) % 150 101 135 100A.sub.R (E.sub.B) % 40 88 60 91ΔH.sub.S +10 +12 +8 +12Compression 85 30 60 34setScorching Over 8 min. 16 min. 9 min.time 30 min. 15 sec. 30 sec.______________________________________
TABLE 7__________________________________________________________________________ Example 15 Example 16 Example 17 Example 18 Example 19__________________________________________________________________________Feed Composition(parts by weight)Vinyl acetate 20 20 20 20 20Ethyl acrylate 35 35 35 35 35n-Butyl acrylate 30 30 30 30 30Ethylene 15 15 15 15 15Monomethoxyethyl maleate 7 7 7 7 7Vulcanizing agentsDDM 0.8 0.8 0.8 0.8HMDAC 0.8Diphenylguanidine 2 2 2 2Diorthotolylguanidine 2PropertiesT.sub.B (kg/cm.sup.2) 136 142 154 159 176E.sub.B (%) 290 280 220 200 210H.sub.S 60 64 66 68 68Heat resistanceA.sub.R (T.sub.B) % 88 86 98 94 96A.sub.R (E.sub.B) % 75 85 90 90 94ΔH.sub.S +14 +12 +6 +4 +3Compression set 35 32 29 25 21Scorching time 9 min. 8 min. 10 min. 10 min. 10 min. 30 sec. 30 sec. 30 sec. 30 sec.Remarks press cure press cure press cure 30 minutes 20 minutes 20 minutes post cure post cure 2 hours 4 hours__________________________________________________________________________ | There is provided an elastomer of acrylic ester type copolymer made up of a monomeric composition comprising; 100 parts by weight of a mixture of (A) 0-50% by weight of a vinyl carboxylate of the formula; R 1 COOCH═CH 2 wherein R 1 is an alkyl group having 1-4 carbon atoms, (B) 0-30% by weight of ethylene and (C) 10-100% by weight of an alkyl acrylate and/or an alkoxyalkyl acrylate; and 2-15 parts by weight of (D) a monoalkoxyalkyl maleate, and which has good curing rate, good processability as well as good storage stability. | 2 |
REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 12/501,774 filed Jul. 13, 2009, which is a continuation-in-part of application Ser. No. 11/845,592, filed Aug. 27, 2007.
FIELD OF THE INVENTION
This invention relates to a novel method and apparatus for uprighting and locating a water sports board such as a kite board, surfboard, or the like, in the water after the kite board or surfboard becomes disengaged from the rider. The method and apparatus also induce the kite board or surfboard to move downwind.
BACKGROUND OF THE INVENTION
Surface water sports have many forms, such as, for example, surfboarding where the surfer rides a surfboard on waves on water, or kite boarding where a kite boarder rides on a kite board floating on the water and uses a wind borne kite to pull him or her and the kite board over and above the surface of the water.
The sport of kite boarding requires a kite boarder to dynamically balance on a kite board on the water surface while he or she is pulled rapidly over the surface of the water by a harness connected by lines which are attached to a wind propelled kite. Sometimes, the kite boarder, for reasons such as hitting unexpected waves, or encountering sudden gusts of wind, falls off the kite board into the water and becomes separated from the kite board. When this occurs, the kite board tends to stop quickly. Meanwhile, the kite boarder and the kite are pulled along for a certain distance by the force of wind caught by the kite. This happens before the kite boarder can spill the wind and bring the kite down on the water surface. It is not uncommon for the kite board and the kite boarder to be separated a good distance from each other. Not infrequently, the kite board inverts in the water after the rider is separated from the kite board. In such situations, it is difficult for the kite boarder, who is mostly submerged in the water, particularly in water reflective sun glare or choppy conditions, to locate the kite board.
There is a strong need for a method of uprighting the kite board, assisting the separated kite boarder in identifying the location of the kite board, and inducing the uprighted kite board to move downwind. There is also a need for a device which carries out the method.
SUMMARY OF THE INVENTION
The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements. The invention includes methods and apparatus obvious to a person skilled in the art related to all water sports involving a board such as a kite board or a surfboard.
The invention is directed to a method of uprighting and identifying an overturned water sports board which comprises removably securing to the above-water surface of the water sports board prior to and during use of the water sports board in the water a flotation mechanism that has sufficient buoyancy to upright the water sports board when it has overturned in the water and sufficient vertical profile that the flotation mechanism protrudes above the water surface and the water sports board and entraps wind to induce the flotation mechanism and the uprighted water sports board to move downwind.
The water sports board can be a kite board or a surfboard. The floatation mechanism can be an inflated float. The inflated float can be hollow and can be constructed of a flexible air impermeable material.
In another embodiment, the floatation mechanism can be constructed of buoyant plastic foam. The floatation mechanism can be constructed of at least two components that can be reversibly folded from an upright position where the two components are spaced apart to a low profile position where the two components are aligned.
The two components of the floatation mechanism can be triggered to assume the upright position by a tension release mechanism which can be activated by a leash trigger which can be releasably secured to an ankle of a kite board rider. The leash trigger can be set to separate from the ankle of the kite board rider at a tension that is greater than the release tension of the tension release mechanism.
The invention is also directed to a detachable water sports board uprighting and directional apparatus comprising: (a) a buoyant body; and (b) a base plate for engaging the above water surface of a water sports board, a first side of the base plate being removably connected to the buoyant body and a second side of the base plate being adapted to be detachably engaged with a water sports board during use of the water sports board in the water.
The water sports board can be a kite board or a surfboard. The buoyant body can be formed from a hollow inflatable air containing apparatus or plastic foam. The buoyant body can be constructed of a hollow, flexible, inflatable, air-impermeable fabric or plastic, and can include a closable air valve for inflating the hollow fabric or plastic. The buoyant body can be formed of air impermeable flexible nylon fabric.
The buoyant body can be constructed of a buoyant plastic foam. It can be in two parts, one of which is a wind catching component which can be pivotally attached to a second part which is a base plate. The buoyant plastic foam can be in the form of a buoyant flip plate secured to a flip arm which can be hingedly connected to the base plate.
The base plate and the flip plate and flip arm can include a resilient mechanism which, when released, can cause the flip plate and flip arm to hinge away from the base plate. The resilient mechanism can be released by a leash trigger which can be releasably connected by an ankle strap to an ankle of a water sports board rider. The resilient mechanism can be one or more elastic shock cords which are under tension when the flip plate and flip arm are aligned with the base plate, and are in relaxed mode when the flip plate and flip arm are hinged away from the base plate.
The leash trigger can be releasably connected to an ankle strap by a first magnet attached to the ankle strap and a second magnet attached to a float at the free end of the leash trigger.
In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions.
DRAWINGS
Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive. The drawings illustrate two physical means for performing the method according to the invention.
FIG. 1 illustrates an isometric view of a first embodiment of an inflatable kite board directional float.
FIG. 2 illustrates a front view of a first embodiment of the inflatable kite board directional float.
FIG. 3 illustrates a bottom view of a, first embodiment of the inflatable kite board directional float.
FIG. 4 illustrates an isometric view of a first embodiment of the inflatable kite board directional float fitted on the top surface of a kite board between the legs and feet of a kite boarder.
FIG. 5 illustrates an isometric view of a second embodiment of a fold-down version of the kite board directional float mounted between the legs and feet of a kite boarder on a kite board.
FIG. 6 illustrates an isometric view of the second embodiment of fold-down directional float with a flip plate on the float in an upright position on a kite board.
FIG. 7 illustrates an isometric view of the second embodiment of directional float with the flip plate in an upright position and an ankle strap connected to the base plate.
FIG. 8 illustrates a top view of the second embodiment of directional float in fold-down position and an ankle strap attached to the base plate.
FIG. 9 illustrates a top view of the second embodiment of the directional float with the flip plate in an upright position.
FIG. 10 illustrates an isometric view of the flip arm and base plate components of the second embodiment of directional float.
DETAILED DESCRIPTION OF THE INVENTION
Throughout the following description specific details are set forth regarding the method and apparatus of the invention in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive sense of the overall scope of the invention.
The method and apparatus according to the invention involve righting the kite board or surfboard after it has become inverted in the water after disengagement from the rider. The method and apparatus also include causing the kite board or surfboard to become more visible to the disengaged rider, who is partially submerged in the water some distance from the kite board or surfboard. The method also includes providing a mechanism which provides resistance to the wind so that it moves the kite board or surfboard downwind in the direction of the disengaged rider. To perform these methods, a number of devices are feasible.
One uprighting device can be a floatation device constructed of buoyant rigid foam, or a flexible device which is air inflated, either before or during use with a pump, or automatically with a compressed air cartridge when needed. Another version of the buoyant device can be of a fold-do construction when placed on the kite board or surfboard but, when activated, erects itself and uprights the inverted kite board or surfboard and in the uprighted position catches the wind to move the kite board or surfboard downwind.
The device can be permanently or removably attached to the kite board or surfboard, or spring loaded, or take some other feasible form. It is advantageous that the method and apparatus according to the invention utilize a floatation device that has sufficient buoyancy that it will upright an overturned kite board or surfboard. It is also advantageous that the floatation device be readily visible, lightweight and relatively inexpensive. It is also advantageous that the device have sufficient vertical elevation to catch the wind so that the kite board or surfboard is encouraged to move downwind.
Such a device can be used for other water sport activities such as wakeboarding or tow surfing, where the sports board can be lost because the rider cannot see the board in the water because of waves or sun glare or other interferences. The method and apparatus according to the invention have the advantages that the board is uprighted, if inverted, and is more readily visible so that it can be easily retrieved by the kite boarder or surfboarder or by a boat, jetski, or some other power means.
As will be recognized by persons skilled in the art, there are many physical ways to carry out the method according to the invention. It is therefore understood that the following description for purposes of illustrating the feasibility of the invention refers only to two physical ways to perform the method and its objectives. Other ways to carry out the invention are included within the overall scope of the invention. For ease of discussion, the following comments and the drawings refer specifically to the art of kite boarding.
As seen in the drawings, FIG. 1 illustrates an isometric view of a first embodiment of an inflatable kite board directional float 10 . The float 10 is preferably constructed of an inflatable, hollow, inverted “U” shaped body 12 , which is formed of a flexible air impermeable material such as rubberized nylon fabric. The float body 12 is removably connected to a flexible T-shaped foot plate. 14 . This foot plate 14 can be formed of semi-stiff rubber or plastic, such as polybutadiene or flexible polyvinyl. An air valve 16 is located in the float body 12 and enables the hollow float body 12 to be inflated. The float 10 is removably connected to the foot plate 14 by a pair of holding socks 18 which fit respectively over opposite ends of the cross bar of the T-shaped foot plate 14 . The pair of holding socks 18 are hingedly connected to the bottom exterior edges of the body of the float body 12 by respective connecting mesh 22 . A carrying strap 20 is attached to the inflatable body 12 . The strap 20 provides a convenient way to carry the float 10 . A pair of straps 26 extend between the free bottom ends of the pair of holding socks 18 and connect the two holding socks 18 together and hold the float body 12 on the foot plate 14 . A series of water transmission holes 24 are formed in the foot plate 14 .
FIG. 2 illustrates a front view of the first embodiment of the inflatable kite board directional float. The sides of the float 12 are indented. The indented sides provide water deflection surfaces when the float 12 is mounted on the kite board (see FIG. 4 ) and reduce drag. FIG. 2 also shows the valve 16 , the footplate 14 , the socks 18 , the straps 26 and the mesh 22 .
FIG. 3 illustrates a bottom view of the first embodiment of the inflatable kite board directional float. The staff of the T-shaped foot plate 14 is oriented at an angle to the cross-bar of the foot plate 14 . This feature enables the float 10 to be oriented on the kite board (not shown) at an angle, which is advantageous for the rider of the kite board. Socks 18 are shown placed over the free ends of the cross-bar of the foot plate 14 .
FIG. 4 illustrates an isometric view of the first embodiment of the inflatable float 10 oriented on a kite board 28 between the legs and feet 32 of the kite boarder. The staff of the T-shaped foot plate 14 extends through a holder 30 on the top of the kite board 28 . The float 10 fits between the legs and feet 32 of the kite board rider. By being offset to the longitudinal line of the kite board 28 , the float 10 catches the wind and tends to point the board forward and in the direction of the kite boarder when the kite boarder falls of the kite board.
A second embodiment of the GO JOE™ is constructed of buoyant plastic foam. This embodiment has the ability to be of low profile by having the flotation part of the device fold down from an upright position to a position that is parallel with the kite board. Then, when activated by a leash trigger, the flotation part of the device springs to a vertical position. The flotation part of the device has sufficient buoyancy to upright the kite board, if it has become inverted in the water. This action is enhanced when the floatation part is in an upright position. In its upright position, the floatation device acts as a sail to move the board downwind.
FIGS. 5 to 10 of the drawings illustrate in detail a second embodiment of the invention, namely the fold-down version of the flotation device. FIG. 5 illustrates an isometric view of a second embodiment of a fold-down, version of the kite board directional float mounted on a kite board between the legs and feet of a kite boarder. As seen in FIG. 5 , the kite boarder, whose feet and legs 40 are shown, stands on the kite board 42 while wearing a releasable ankle strap 44 that is connected via a leash to the fold-down flotation device 46 . The floatation device 46 , in its retracted fold-down position, is relatively flush with the deck of the kite board 42 and causes little interference with the feet of the kite boarder 40 .
FIG. 6 illustrates an isometric view of the second embodiment of fold-down float with the flip plate of the float in an upright position on a kite board. FIG. 6 shows the fold-down device in its activated, erect position, with the flip plate 48 upright, on the kite board 42 , after the kite boarder has fallen off. The leash trigger 64 has separated from the ankle strap 44 (not shown).
FIG. 7 illustrates an enlarged isometric view of the second embodiment of float with the flip plate in an upright position and an ankle strap in a position to be connected to the base plate. As seen in FIG. 7 , the fold-down version of the flotation device 46 , in its activated upright position, with flip plate 48 raised, has the ankle strap 44 cooperating with the leash trigger 64 . The ankle strap 44 , which is typically made of webbing and neoprene, has a magnet 78 which is attached by sewing or other fastening means to the strap 44 . The magnet 78 releasably connects to a magnet 68 that is attached to the free end of the leash trigger 64 . At the magnet connection point, the device 46 includes a leash float 66 , typically made from EVA foam, which keeps the leash magnet 68 from sinking in the water. The leash trigger 64 is typically made from flexible polyurethane cord. The leash trigger 64 is connected to a hook 56 that is built into the base plate 52 . The base plate 52 connects to the kite board (not shown) by fitting into a recess that is built into the grab handle 60 . The grab handle 60 is joined to the kite board using screws or some other suitable attachment means. A flip area 50 is pivotally connected to the base plate 52 . The flip arm 50 , base plate 52 , hook 56 and grab handle 60 are typically constructed from injection molded nylon. A buoyant flip plate 48 is connected by glue or other suitable securing mechanism to the flip arm 50 . The flip plate 48 is typically constructed from EVA foam which provides buoyancy. Flip plate 48 provides the necessary kite board uprighting ability to the device and when in an upright position acts as a sail-like structure.
FIG. 8 illustrates a top view of the second embodiment of the float with the flip plate 48 in fold-down position and an ankle strap 44 attached by trigger leash 64 to the base plate. As seen in FIG. 8 , the floatation device 46 is in its retracted, fold-down position so that the flip plate 48 is relatively flush with the top surface of the kite board (not shown). The ankle strap 44 has a Velcro loop 72 and Velcro hook 74 sewn or attached to it to permit easy releasable fitting onto the kite boarder's ankle. A webbing tab 76 is sewn to the ankle strap 44 to allow for easy removal of the ankle strap from the ankle of the kite boarder, when required. The flip arm 50 underneath the flip plate 48 (partially visible) is pivotally connected to the base plate 52 with elastic flip arm shock cord 54 (partially visible). The ankle strap 44 is attached by magnet 78 to magnet 68 of the leash float 66 and leash trigger 64 . The opposite end of the leash trigger 64 is secured to base plate 52 (not visible but see FIG. 7 ). The grab handle 60 protrudes upwardly through an opening in the flip plate 48 . The elastic flip arm shock cord 54 is installed onto and between the flip arm 52 and the base plate 50 so that it is under tension. It therefore acts as a spring loaded hinge joint. The tension on the shock cord 54 encourages the flip arm 52 to spring up into a vertical position when released by hook 56 . The tension load on the shock cord 54 is increased as the flip atm 52 is folded down onto the base plate 52 . The end of the flip arm 52 , opposite to the hinge joint with the base plate 52 , engages with and is held in place by the hook 56 (not visible but see FIG. 7 ).
FIG. 9 illustrates a top view of the second embodiment of the float with the flip plate 48 in upright position to expose the base plate 52 and hook 56 . As seen in FIG. 9 , the leash trigger 64 connects to a trigger line 62 which in turn is connected to the hook 56 . The hook 56 , at its base, has a hinge connection with the base plate 52 . A hook shock cord 58 , which is separate from the flip arm shock cord 54 discussed above, is connected under tension to the hook 56 and the base plate 52 and keeps the hook 56 in a closed position. The hook 56 can be moved to an open position by being pulled by leash trigger 64 . This hook opening action enables flip arm 50 and flip plate 48 to release and spring pivotally to an upright position as discussed above in association with FIG. 8 and shown in FIG. 9 .
FIG. 10 illustrates a detailed isometric view of the flip arm 50 and base plate 52 components of the second embodiment of the float. As seen in FIG. 10 , the flip arm 50 , (which has the flip plate 48 attached to it (not shown)), is in upright position relative to the base plate 52 and hook 56 . The end of the flip arm shock cord 54 at the top of the flip arm 50 and the end of the hook shock cord 58 adjacent hook 56 are visible. The shock cords 54 and 58 are connected as described above in association with FIGS. 8 and 9 .
In use, the leash trigger in the fold-down version of the floatation device illustrated in FIGS. 5 to 10 is engaged and activated by the kite boarder wearing an ankle strap. The ankle strap has a magnet sewn into it. A matching leash trigger secured to the GO JOE™ also has a magnet built into it. These two magnets join together to hold the ankle strap and the fold-down flotation device together. After mounting the kite board, the kite boarder connects the leash magnet 68 to the ankle strap magnet 78 . The magnet combination provides an easy and effective way to connect the ankle strap 44 to the leash trigger 64 . When the kite boarder falls from the kite board, the ankle strap 44 pulls the leash trigger 64 , which in turn releases hook 56 to enable the flip plate 52 and flip arm 50 to rise to their vertical position. Activation by the leash trigger 64 on the hook 56 takes less force than the joining force of the two magnets 68 and 78 . Thus the leash trigger 64 and release hook 56 are activated before the magnets 68 and 78 separate as the kite boarder falls from the kite board.
Once the board, encouraged by upright flip plate 48 catching the wind, drifts back to the kite board rider, the rider resets the flotation device to its fold-down position by pushing down on the flip arm 50 and flip plate 48 to engage hook 56 . The rider then puts his feet back on the kite board and reattaches the leash trigger magnet 68 to the magnet 78 on the ankle strap.
A farther conceivable embodiment of the fold-down flotation device illustrated in FIGS. 5 to 10 can have a keyless remote that activates the trigger on the device, thereby causing the flip plate and flip arm to spring up to vertical position.
A commercial, embodiment of the invention is available under the trademark GO JOE™ from Ocean Rodeo Sports, Victoria, BC V8M 1Z9, Canada.
While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope. | This invention relates to a novel method and a novel inflatable flotation device for the method which are used in association with water sports boards such as kite boards, surfboards and the like, for the purpose of uprighting the water sports boards when inverted and encouraging the water sports boards to be moved by the wind in the direction of a water sports board rider when the rider becomes separated from the water sports board. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims as priority date provisional applications filed by the same inventor: (1) Application No. 61/744,277 filed on Sep. 24, 2012 entitled. “Innovation Package G29” and (2) Application No. 61/724,916 entitled “Hybrid Coins” filed on Nov. 10, 2012. It also claims as reference U.S. Pat. No. 8,229,859.
BRIEF SUMMARY OF THE INVENTION
[0002] Previous inventions (e.g. U.S. Pat. No. 8,229,859) have established digital money minting capabilities. Such digitally minted money needs to be engineered for efficient transactions. This invention addresses a host of complementary procedures and implements designed to facilitate effective, smooth, and trouble-free exchange of digitally encoded transactional value.
[0003] The invented procedures and implements may be categorized into two broad categories: physical transactional coins, referred to as Hybrid Coins, and Mint operation exchange, where a core mint interacts with front mint so that in combination the various mints and digital money management center can efficiently implement the digital formula and the particular solution that is being used to construct a safe and effective digital currency (e.g. BitMint designed on the basis if U.S. Pat. Nos. 8,229,859, and 6,823,068).
[0004] The hybrid coins are constructed for various denominations, for various safety options, and for various transactional environment. Essentially to the various coins is the electronic storing of the digital information of the coin, so that it is clear to its receiver that the coin is “virgin”—its digital content was never exposed, and hence could not have been redeemed earlier, and otherwise, same digital content is engineered for uploading online to effect due redemption.
[0005] The mint arrays in this invention offer a variety of responsibility distribution between the core and front mint so that various financial and trading conditions cam be efficiently addressed. In particular the ultimate responsibility to redeem bona fide digital money may be vested in the core mint or in various of the front mint, and perhaps in some combination.
[0006] Taken together these invented procedures and implements provide for an effective implementation of the newly invented digital money solution, and their smooth and convenient deployment in a variety of trading situations.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0007] Not Applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
[0008] Not Applicable.
BACKGROUND OF THE INVENTION
[0009] The newly emerging digital money mints require a careful design and construction of procedures and implements to allow for the digitally minted money to spread into the hands of the trading public. Such procedures and implements are the subject of this invention.
DETAILED DESCRIPTION OF THE INVENTION
[0010] The invention is described in two parts:
1. Mint Array Design (Core Mint v. Front Mints) 2. Hybrid Coins
1. Mint Array Design
[0013] The Core BitMint projects to any number of front BitMint entities, and the relationship may be one or a mix of the following:
[0014] Royalties Payment
[0015] System
[0016] Dead Coins
[0017] Live Coins
[0018] Each front mint may take the role of the Core, and project to its own front entities. In this way one may define a mint-tree (hierarchy).
[0019] This relationship will allow front mint to be consistent with parameters and regulations prevailing in their domain, while enjoying technical and functional support from the Core BitMint.
[0020] Royalties Payment: In this mode Front BitMints pay use royalties to the Core for using its technology, and no further relationship or obligation exists.
[0021] System: In this mode the Core delivers, installs, and provides training and maintenance to the front—or any part of this list. In its full implementation the Core provides a ready-to-mint system, maintains it, and trains its operators.
[0022] Dead Coins: In this mode the Core delivers to the front valueless minted-coins per the front request. The front would then ‘charge’ these dead coins, and ‘bring them alive’ versus its customers. It would be the Core responsibility to insure the integrity of the bits and their identity, and to equip each coin with the headers and trailers as needed. The Core would identify the core mint, the front mint, any other parameters requested by the front, and then add, say, as trailers, any cryptographic parameters as needed.
[0023] Live Coins: In this mode the Core will deliver live, charged coins to the front mint. The front mint will pay, or promise to pay for these live coins, and then, if necessary, process these coins to serve for the purpose of the front.
[0024] The responsibility and involvement of the Core with the business of the front entities is minimal in the royalties mode, a bit greater but still limited in the system mode, also limited in the dead-coins mode, and the highest in the live-coins mode.
[0025] In the system mode the Core is responsible for the integrity of the delivered system, but not for its use. In the dead-coins mode, the Core is responsible for the quality of the bit identities of the coins, but not for its money value or use. In the live-coins mode the Core is responsible for the money value of the coins. This responsibility may be of two categories:
[0026] front-limited
[0027] front-extended
[0028] In the front-limited mode the Core has a contract with the front whereby the front pays or promises to pay for the delivered coins, and the Core agrees to redeem these coins when submitted by the front for redemption. The Core will not be involved in any business arrangement between the front mind and its customers, and will not interact with those customers. In the front-extended mode the Core will interact with the customers of the front, even directly redeem its coins to them.
[0029] Basically, the idea of live coins, is to alley the customers apprehension with regard to the trustworthiness of the front mint. The live-coins setup will give the front customers the peace of mind that their money is kept the trustworthy Core.
[0030] For example, customers may be reluctant to trust their money to an unknown Front company that offers them money transfer, micropayment, charity contribution, etc. However, if the terms of the coin are such that if the Front does not pay, or goes out of business, the coin can be redeemed at the Core.
Buffer: Layered Mint Operation
[0031] It may be advisable to construct a buffer between the entity that mints the coins and the entity that trades them with the public (its customers). Such in the case in the “live coin” Core-front business setup. A buffer will allow a Core mint to mint coins that may either be traded as is by the front mint (in this case this entity is not much of a mint), or it may be first processed by the front mint, with both the header and trailer possibly adjusted, added-to, to serve the purpose of the front. The value bits will be minted by the Core based on the Core's recognized trustworthiness. For example the front could add cryptographic parameters to the trailer. (See FIG. 1 )
[0032] Illustration: the add-on header information (added by the front) will include payment terms according to which the Front will redeem the coin in favor of its customer. The trailer add-on may contain a signed hash to identify the coin as re-minted by the Front.
Bit-Masking Trade Tracing
[0033] This procedure is based on the notion that a BitMint coin is constructed from a large number of ordered bits. So much so that anyone who knows the identity of, say, 80% of the bits is not likely to have guessed it right but is overwhelmingly likely to have been given the bits. Accordingly Alice could pass a BitMint coin to Bob, and mask the identity of a small number of bits, say, selected randomly. Bob will have knowledge of the identity of sufficient number of bits to claim that he is in possession of the coin, but the identity of the masked bits will connect Bob to Alice, as the payer of the coin. If Bob had received the coin from Carla, then it is virtually impossible for Carla to randomly select the very same bits as Alice for the purpose of masking their identity as she passes the coin to Bob. Hence the identity of the masked bits points to the source of the coin. Bob, on his part may pass the coin to David—masking some additional bits. The identity of the bits that Bob masked will point to him as the source of the coin. And so on, when David passes the coin to Eve he masks some more bits. And on it goes. If Alice will examine a coin held by Eve she will be able to determine that it was a coin she held because the bits that she masked giving the coin to Bob are all masked. And since the number of masked bits is so small compared to the number of bits in a coin, the chances that all of Alice masked bits are masked by someone else are very slim.
[0034] The selection of bits to mask may be done via a selection algorithm that takes into consideration any information on the coin, its value bits and all the other coin information (header and trailer). So for each coin the selected bits are different, but given a coin the selection algorithm may be readily replayed.
[0035] If an approval hierarchy is used then it is advisable that the number of masked bits is smaller than the number of masked bits between layers on the approval tree.
Samid Cipher RFID
[0036] Samid cipher U.S. Pat. No. 6,823,068 may lend itself to RFID technology. The key may be hard-wired as matrix of bits where every two bits represents one of the four letters: X, Y, Z, and W. The cipher will operate on basic knowledge where the plaintext comprised of a non-repeat series of X, Y, Z and W letters guides a traveling path on the key, and produces a traveling trace marked as a sequence of Up, Down, Right, and Left. The stream comprised of U, D, R and L letters will constitute the ciphertext. The plaintext may be hard-wired, firmware, or software. Upon triggering from the outside the plaintext will be fast processed through the key (the matrix) to yield the ciphertext as output. Conversely, the ciphertext may be resident in the RFID, and upon initialization, the ciphertext will be processed via the key (the bit matrix) to yield the plaintext as output. In both cases the Samid cipher will be implemented.
[0037] There are various uses for this arrangement:
[0038] Hiding content of the RFID: an RFID tag may contain information that needs to remain private. In a regular ID any reader would activate the RFID and read the information in it. That information may be encrypted and be interpreted through an exhaustive look-up table. But an easier alternative is to fit the secret RFID information as software, firmware or hardware in the tag, and refer to it as plaintext. The Samid key will such that the size of the output ciphertext will be much larger than the size of the plaintext. And also there will be a great deal of degree of freedom for the encryption process to yield any of a large variety of ciphertexts, all of them decrypt back to the same plaintext, if the decryptor has possession of the right key.
[0039] So, in this arrangement only the key will have to be known to the reader of the RFID, and a large number of related or unrelated RFID tags will be sharing the same key. Each tag will contain some specific and unique content. Upon activation, reading, the content will be processed through the Samid cipher key, and yield an output to be read by the decoder/reader. The reader will have the key in its reading device, and will be able to instantly decrypt the ciphertext, and display and interpret its contents. An unauthorized reader, will activate the RFID, but will be unable to interpret its output because of not having the key.
[0040] What is more: the size of the ciphertext will vary, and so the hacker will not be able to conclude from the size of the ciphertext, how much contents (plaintext) is stored in the device. Also the activation will be able to include random data from a clock or from the environment, and that data will guide the encryption each time to a different ciphertext, a further difficulty for the cryptanalyst.
[0041] Similar setup could be done with Flash technology. A flash memory may contain a content X (may be a digital money string or anything else). The device that holds this memory card, activates the device, so that X is encrypted via a well defined firmware, say key, and produces Y. A verifier attests to the presence of X in the drive on account of detailed examination of Y.
AutoKey Authentication
[0042] Alice holds string X, and wishes to signal and prove that holding to Bob. If she sends X in the clear, Eve, the eavesdropper will catch it. If she had a shared key with Bob she could use it to encrypt X and send it to Bob. Otherwise she could use diffie Hellman or any other cryptography between strangers—with all the weaknesses thereto. So instead she could use an Auto-Key, based on the crypto-cipher and crypto addition presented by this inventor before. Accordingly Alice will separate from the string t bits as described in the crypto cipher, use these bits to find where to dissect the rest of the string, and then use one part so dissected as plaintext and the other as a Samid cipher key. Then Alice will encrypt the plaintext using her derived key applying the Samid cipher. She will communicate the result to Bob the verifier. Bob who knows X will repeat Alice process to check if Alice ciphertext agrees with his calculations, and if so, he is rest assured that Alice has X. This verification happened without any exchange of any key. Eve, the hacker will not be able to reverse Alice ciphertext, Y to the original string because as it has been shown there, there are infinite number of strings that process to the same Y.
2. Hybrid Coins: Off-Line Digital Money
[0043] Gideon Samid, Provisional Application US PTO Nov. 9, 2012
[0044] Abstract: Digital money is native to online applications, and inherently problematic in off-line circumstances where one suspects that the same digital string was used earlier, elsewhere, or even later, putting the payment in doubt. We propose effective means to manage such risks and operate a viable off-line digital payment solution. The central concept is that of a ‘hybrid coin’ or say, a ‘dynamic coin’—a physical device containing, dispensing, and in some cases, accepting digital cash. The device, the coin, will be tamper-resistant to a degree commensurate with its capacity. Security will be safeguarded by insuring that the cost to counterfeit exceeds the maximum money content of the coin. Different coin denominations will have different tamper-resistant measures, and these measures will be dynamically adjusted to protect against increasingly more sophisticated counterfeit measures. The use of the coins will be either via the regular hand-over, or by ‘draining’: namely, one could pass to the payee a bunch of coins trusted for their declared money content, or one would connect the coin to a recipient device, and drain, pay off a portion of the stored value. We distinguish between the following coins: (1) “gold coins” which are minted by digital currency mint, and their seal is intact, indicating they were never bled, drained, and hence satisfying the recipient that these coins carry their nominal (mint stamped) value. (2) “silver coins” which are gold coins that have been partially used (drained), and now contain less money than the originally minted amount. (3) “bronze coins” which have been drained, or bled, but which have also be replenished from another coin. The coins are optionally battery operated, marked by a unique serial number, and they may be shaped like regular coins. The digital money in the coins can be defined in terms of dollars, Euros, Yuan, or any other currency, as well as defined against gold, or any other commodity valuable. Hybrid coins may be uploaded to online use, and altogether facilitate an important facet of normal civil trade practice. Hybrid coins provide continuity of habit relative to regular coins, and respond to every day functionality needs. Hybrid coins may also be found useful in mass emergencies, when power lines are down, communication networks collapsed, and off line payment is the only way.
Introduction
[0045] There are several solution options for online digital money. Yet to prevail in the marketplace it seems necessary for a solution to be extendible to off-line circumstances. For centuries people have been paying each other by handing over a physical token, a representative of value. For behavioral continuity this is a must. In practice there are two categories of situations where the off-line payment option is critical: (1) immediacy and simplicity, and (2) emergency—short-lived, or durable. Nothing electronic, or computer-based can compete with the immediacy and simplicity of hand to hand coin transfer. In many daily circumstances resorting to an electronic gadget, having to punch buttons, and having to participate in a person-machine dialogue, is too much of a burden. Electronic transactions inevitably rely on electric power supply: be it a battery, or be it the grid. Both may be interrupted, impaired and become dysfunctional—disabling payment altogether. Our modern societies are comprised of very crowded urban areas where millions of strangers share a territory and public resources, and a payment mechanism is the only way to get such a crowd into a mutually beneficial cooperation. We cannot risk the loss of the payment option, exactly when it is needed most.
[0046] We conclude then that we must allow for a seamless back and forth motion between the online payment mode and the offline payment mode, and the concept of Hybrid Coins proposes a solution for this challenge.
[0047] Let us first define and characterize digital money.
[0048] Digital Money is money that expresses its value via digitized data in a medium-un-tethered fashion. Since all data can be reduced to an equivalent binary string, we can further narrow the definition to say that digital money is money that expresses its value via a bit string, or, say a ‘binary string’ where the identity of the string bits {0,1} carries the monetary value regardless of the medium through which these binary digits are written or expressed.
[0049] The logic, mechanism algorithm or concept that associates a given binary string with a monetary value is of no importance for our matter herein. A hybrid coin should extend to off line payment any digital money solution where a bit string represents value, regardless of the concept, formula, logic, mechanism that establishes the value of the string.
The Hybrid Coin Concept
[0050] A hybrid coin is a physical device that by handing it over, one carries out a payment corresponding to the face value of this device, where the face value is reflected by a bit string that changes ownership from the payer to the payee as the coin is handed over. Ownership is expressed as ‘the right to use, dispose, pass-on this string as the owner sees fit.
[0051] According to the above definition the bit string—the digital money—does not have to be inside the coin, or passed along with the coin. All that is needed is for the ownership of the associated bit string to be exchanged between payer and payee. Obviously, if the coin contains the string, the ownership passes on. In the “no-string-inside” option the coin may serve as “proof of ownership” which can be used in some subsequent protocol in which the money is actually transferred. FIG. 1( a ) depicts the “no string inside” option, and FIG. 1( b ) depicts the “string inside” option.
[0052] In FIG. 1( a ) “no string inside: Alice passes to Bob a $10.00 hybrid coin, and this act confers a transfer of ownership of a bit string that resides in the clouds of elsewhere outside the coin. As the coin is transferred from Alice to Bob, the respective ownership of the corresponding bit string is also passed from Alice to Bob. Passing the string from Alice to Bob, does not necessarily erase the string from Alice memory. This leads to the fundamental issue of double spending, namely Alice, by mistake or by fraudulent intent may re-transfer ownership to the same bit string to a third person, thereby violating the association between the bit string and the socially accepted sense of value. Since the bit string represents value in the context of some comprehensive solution to digital currency, we may assume that the issue of double spending is resolved and taken care of in the context of that solution.
[0053] FIG. 1( b ) “string inside” represents the case where the physical device, the hybrid coin, contains the digital money, and hence, the passing of the coin amounts to passing the string—the money itself.
[0054] A string-inside hybrid coin is produced and manufactured, and also optionally distributed by an entity referred to as the mint. The mint assumes the responsibility to the monetary value of the coin it issues, mints.
[0055] In addition to the standard hybrid coins described above the mint may wish to construct: (1) empty coins, and (2) networked coins. Empty coins are simply bit-money containers that may be filled with bit-money by traders to dispose of them at a later time either by feeding their bits to a payee or by passing the coin to a trusting payee. Networked coins are hybrid coins with a phone-like connection to networks. Such “live hybrid coins” may have their contents instantly, and continuously verified by the continuously connected mint.
[0056] The string-inside case may be categorized as follows: (1) Gold coins: a pristine, virgin coin that has not been broken-into, meaning not ‘opened’, nor tampered with, relative to the state in which it was issued by the mint. (2) Silver coins: a gold coin that has been worked on, and its inside money string was at least partially exposed; (3) bronze coins: a silver coin to which a money bit string has been inserted from a source other than the mint.
[0057] Gold coins are transacted on account of the evidence of the authenticity of the declared mint, and on account of their virginity, namely by convincing the payee that the handed-over coin has not been tampered with since it was minted, and hence its declared face value is inside the coin with the full faith of credit attached to the mint itself. The evidence of virginity may be ‘self evident’—judged by simple visual inspection, or it may be instrument based—verified by a testing device relying on scientific principle that is used by the coin. A combined measure is also possible.
[0058] A silver coin may be totally drained, and hence worth nothing, or it may be partially drained, and in that case a reader may be needed to establish its residual value, and confirm that the digital money still there is indeed the original money put there by the mint, and not a refill from an unknown source.
[0059] A bronze coin will also need a reader to read the digital money residing in the coin, but in addition the payee will require means to authenticate the present string as its source may be questionable.
[0060] Silver coins must be born from gold coins, and ‘give birth’ or transform into bronze coins, but bronze coins don't have to have silver status ancestry. A trader could construct his own bronze coin, and fill it with digital currency on his or her own. If the coin is characterized and identified as ‘bronze’ then the recipient would not care whether the coin originally was a gold coin, or it started as a bronze status. The security implications are the same. The mint might issue ‘empty coin’—which are essentially empty containers for digital currency, expecting the trader to fill us these containers on his or her own. In this case the mint will have no liability as to the ill use of such coins by fraudsters.
[0061] The reader of contents for each hybrid coin may be built into the coin, and the result is electronically computed in the coin itself. In that case the present value of the coin may be communicated electronically to an electronic device with which the coin communicates, and/or it may be displayed on the coin for the payee to read without any instrument. The reading circuitry of residual value will have to be trustworthy and tamper resistant.
String not Inside Hybrid Coin
[0062] In this mode possession of the coin, once verified by the authority that manages the bit money string, will be declared as given to the holder of the coin. When the coin holder passes the coin further to a subsequent trader then the string management authority reconfirms the new holder of the coin, and registers the new possessor of the coin as the new owner of the string. A bit money string owner can redeem it, or download it, or dispose of it as he sees fit according to the operating rules of the mint.
[0063] “String not inside” may be operated mainly with gold coins. The monetary value of the string-not-inside must be commensurate with the security and trustworthiness of the technology that is used to confirm the possession of the hybrid coin that is associated with the particular string.
[0064] The advantage of the ‘string not inside’ mode is that payment may be conditional. A ‘string inside’ coin, say denominated for $100, will allow the holder of the coin to trade it as a physical object for its nominal $100 value, and will allow him to break it open, suck out its bits and use them as un-tethered cash. A ‘string not inside’ gold coin for the same denomination, would be clearly marked with a payment code, or say a payment condition code that would indicate to the recipient that this coin does not contain money per se, but its possession will allow one to claim the denominated sum if, and only if a set of conditions indicated by the marked code is fulfilled. The recipient then will accept the coin as a gold coin for its nominal value, if he can satisfy the payment conditions indicated by the code. (Or, if he or she believes they can trade it further to a complying recipient). The possessor of a gold ‘string not inside’ coin may break it up, connect it electronically to the mint—prove to the mint that the respective coin is in his possession, and when so, the mint will demand prove of satisfaction of the other payment conditions, and upon a satisfying proof, the mint will communicate the denominated sum to the claimant.
[0065] So for our $100 ‘string not inside’ coin, once broken-in and hooked through a phone to the mint, the mint might launch a challenge-response dialogue with the coin. The coin will be tamper resistant and have a chip inside with unique data and logic to satisfy the challenge-response dialogue issued by the mint. The mint will then be satisfied that the particular coin is in possession of the claimant, and will then ask for a proof that the claimant belongs to, say, a club, by asking for a club membership PIN to be communicated to the mint, or to be demonstrated for having possession of the PIN using a challenge-response dialogue. And only when the two conditions are met, the digital money worth $100 is sent down the electronic channels for the claimant to use as cash.
Technology of Hybrid Coins
[0066] We discuss the following technological challenges:
Mint Assurance Virginity Assurance Silver and Bronze Coins Value Determination Construction technology
[0071] In each case the technology will have to correspond to the denominated value of the coin, aiming to insure that the cost to counterfeit or violate the coin will be at par or more with its denominated value. Coins with large denominations will allow for more expensive technology.
[0072] Unlike the case with ordinary coins, hybrid coins allow the mint to (1) monitor counterfeit activity, and (2) effectively fight it strategically. Coins may be minted with a built-in expiration date. By that date the coin will have to be cracked open, and its content redeemed. This will expose the number of coins that circulate while being counterfeit. Also, if a major counterfeit action happens, the mint can wholesale invalidate the type and denomination of the violated coin, and ask owners of such coins to redeem them electronically by breaking them up, and testing the validity of the money within. This can be done in combination with a strategy of manufacturing the coins with expensive machines that become economical only for large quantities. Counterfeiters will also have to invest in expensive counterfeit machinery, which will become useless the moment the mint invalidates that type of coins.
Mint Assurance
[0073] Traders need to be assured that the coin they trade with was manufactured by the mint, and not by a counterfeiter. For that reason any hybrid coin will come embossed or written with a serial number, allowing a trader to verify the coin. Naturally verification will occur more frequently for high denomination coins. The mint will use technology to create confidence about its coins. The mint assurance technology will be of two kinds or combination: (1) visible measures, (2) device tested measures. The mint might use embossing, imprinting, type-casting, and exotic materials to make it difficult to copy and counterfeit. The higher the denomination, the greater the measures of visible uniqueness. The mint may also embed indicators that would require an inspection device to probe. The device tested technology might be based on electromagnetic phenomena, or on chemical reaction.
[0074] As an example the coin may be covered with color changing plastic that changes its color upon shining on it with a special range of electromagnetic radiation. This technology is used in sunglasses that become dark upon sunlight, and return to sheer status in room situation.
[0075] Various holographic techniques can be used to build a sophisticated coin that will frustrate amateur counterfeiters, and all others except top professionals, and will also require the counterfeiter to counterfeit only high denomination coins.
[0076] A simple mint assurance will be given by the serial number and minting date imprinted on each coin. A recipient trader will be able to text the serial number and date to the mint (or pass it on otherwise), and the mint will respond either with an authentication—yes, such a serial number corresponding to the sent date is a the serial number and a date of a valid coin. It is not a very good assurance, of course, but it has some base value.
[0077] One special way to provide mint assurance is the cryptographic window method. See below.
[0078] The above address the issue of mint assurance—assurance of authenticity of the coin as being issued by the declared mint—with respect to Gold coins. Once opened, broken-in, the assurance of the mint will be taken care of through the electronic exchange with the computing device that would be connected to the coin. There are various common cryptographic means to assure the validity of the declared manufacturer of a device. Such ‘silver coin mint assurance’ is a different challenge from the ‘gold coin mint assurance’.
[0079] Cryptographic Window Mint Assurance:
[0080] This method is more attractive for high denomination gold coins. The gold coin is fit with a dynamic display window, LCD or similar display technology. The small display will feature some sequence of alphanumeric characters based on some cryptographic protocol. The recipient of the coin will communicate to the mint the serial number of the coin, and the current display string. The mint will respond with an OK, if the communicated display string is the expected one, and “not-ok” otherwise.
[0081] This crypto window may be implemented using any of the prevailing techniques used by hardware devices that compute keys, display them and change the display every 60 seconds or so. Such devices are used to authenticate a user to an approached bank, and they could also be used to authenticate a coin, especially of high denomination.
[0082] The coin so fitted will have two separate electronic circuitry. One is the circuitry that is used once the coin becomes silver, and is communicating value and money transfer with the hosting computing device, and the other circuitry will be for mint authentication as a gold coin status, with virginity intact.
[0083] The mint assurance circuitry can easily be implemented using hardware oriented cipher, like a typical LFSR stream cipher, or the cipher described in U.S. Pat. No. 6,823,068. Every so often the time count by a built in clock will be used as plaintext, and the corresponding ciphertext will be displayed on the crypto window. The coin recipient, or say, the coin verifier, will text the code to a mint number, and get a text back: OK, or not-OK, status because the mint will know from the serial number what is the tamper-resistant key in the coin and compute the corresponding display (ciphertext).
[0084] Any other mechanism where the coin will display a seemingly random display that changes frequently enough, will serve as a means to assure the identity of the mint.
Virginity Assurance
[0085] “Gold coins” must be traded with the confidence that they are ‘virgin’—unopened, unused. Virginity may be based on basic old fashioned technology of ‘scaratchable pads’. A simple heavy stock paper ticket will certify the denomination of the coin, and will feature a scratchable stripe. Upon scratching the stripe, the bar-coded digital coin will be exposed, and be entered via a bar-reader into a payment oriented electronic computing device. Once scratched it is clearly not virgin anymore, and no one would be fooled to regard it as such. This solution may be a bit inconvenient since it requires a bar code reader.
[0086] The pharmaceutical industry is using a variety of technologies to prove the ‘virginity’ of packages of medications. These wrappers etc. may be copied for assuring the virginity of coins.
[0087] Coins may be wrapped with a plastic cover fitted with a ‘breaking line’. Upon a slight blow, like with a heavy book, or a small hammer, the plastic cover will break along the breaking line, and the virginity will be clearly lost. The coin exposer will then be able to connect the coin with a payment oriented computing device and use the money therein.
Silver and Bronze Coin Value Determination.
[0088] A silver coin will have to provide first mint assurance, and then “no bronze” assurance, namely assurance that the coin has not be refilled with bits, but that all the bits to represent money therein are originally minted by the mint. Mint assurance and residual value assurance will be provided through the communication protocol between the coin and the payment oriented computing device with which the coin will be connected.
[0089] One common way to provide assurance of mint and residual value is for the coin to be tamper resistant and communicate with the connected computing device by encrypting all outgoing data from the coin using a private key put there by the mint, to allow the computing device to read it using the corresponding published mint public key. There could be a large variety of private-public key pairs that are distributed and used according to denomination, date of minting, etc.
[0090] There are several common hardware solutions to insure that the file that holds the money bits of the digital currency is not a refill but an original mint-placed bits.
[0091] Bronze coins require no assurance, they simply serve as bit money container, and the validity of the money will have to be ascertained outside the coin.
Construction Technology
[0092] Construction Technology will be discussed by topics:
circuitry power options Hook-up technology shape, size and form
Circuitry
[0097] The basic circuitry of the hybrid coin may be comprised of the following functions: memory—where the digital money is housed, a processing unit that reads/writes into the memory and optionally erases parts thereof, a value display unit that is connected to the processing unit, a crypto processor that is connected to the processing unit on one hand and to a hook-up apparatus on the other hand. The hook-up apparatus is connected to the payment oriented computing device that communicates with the hybrid coin. See FIG. 2 . The hook-up mechanism may be touch-based, swipe based, or distance based including NFC, Bluetooth, Infrared, WiFi, phone connection, etc.
[0098] The coin comes with its coin data in memory. The memory may also include various mint data to help authenticate the coin itself. The crypto processor has a built in keys and operates through a variety of optional protocols, to help hinder counterfeiting. One such protocol is to encrypt all coin data that is processed by the processing unit and fed into the crypto processor, by the crypto processor, and send it out as a ciphertext. The payment oriented computing device over the hook-up apparatus will use the mint public key corresponding to the coin's private key, to ascertain that the coin is authentic.
Power Option
[0099] The hybrid coin can be power-less and operated only through the power of the device it is being hooked to. Or it can have a tiny built in battery only for the secondary circuitry to authenticate the mint, or it may have a built in battery to power up the silver operation for display of value, if such a window is presented (normally in the high value denomination coins), and for the dialogue with the hooked computing device. The battery could be replaceable and latched through a small slit at the side of the coin.
Hook-Up Technology
[0100] The coin could allow for one or more hookup options including touch hook up, nominally via a USB cable with the coin being equipped with a mini USB female port. Or with swipe option where the coin is being equipped with a magnetic card, or with a distance based communication, which is less secure.
Shape, Size, and Form
[0101] The basic hybrid coin will be round and thin, to emulate the familiar quarters or dollar coin. Its fabric will be reminiscent of a regular coin. Its edge might be jagged. See FIG. 3 : items (a,a′,a′) represent a mini USB female port, (b) represents the covered slot for a coin battery, (c) represents the residual value display window. In the drawing it shows $8.75, indicating that the coin has lost its gold status (lost its virginity), was already partially drained (in the mount of $1.25), and the residual value of the coin is $8.75. On the back face, item (d) represents the mint-assurance window. The display on the window changes frequently as computed by the crypto processor inside the coin. That display number if computed based on a built in clock, and on the serial number of the coin, and on built-in hardware constructed cryptographic key. The recipient trader will text or otherwise communicate to the mint the serial number of the coin, and its display number, and the mint will text back whether this coin is bona fide or counterfeit because the mint will have the data in all its coins, and could follow the computation of the coin, and verify the displayed code.
[0102] Other shapes, rectangular, credit-card like will be also available. Different shapes will accommodate different options for proof of virginity and mint assurance. The round coins have the advantage of behavioral continuity.
[0103] There might be a distinction in the size of the coin based on the denomination, so that larger denomination coins will be of a larger size.
Use of Hybrid Coins
[0104] We discuss use according to the two main categories of use:
Fast cash-and-carry transactions Emergency Use
[0107] We also discuss briefly the economics of hybrid coins. On top of the expenses needed to mint the digital money per se, there will be cost for manufacturing the coins. This cost may be handled by a purchase commission computed for each denomination based on the actual cost of the coin. In special cases where a coin represents the exact fair for a ride, for example, then the train or bus authority may bear the cost of the coin, so that commuters pay only the face value. The train or bus system will save on fare handling and will find it advantageous to pay the coin commission.
Use of Fast Common Cash Transactions
[0108] We discuss fast common cash transaction use according to the following topics:
denomination shape and format distribution life cycle purpose online-offline interplay security power supply coupons and non-dollar representation acceptability
Denomination
[0119] We expect hybrid coins to first extend from regular coins, namely to be used in denominations starting from $1.00 to $10.00. These small denominations will require corresponding simple counterfeit technology, and hence the cost to be born to produce them will be small. These coins are expected to be long lasting before their virginity is tampered with because of their low denomination. Higher denominations will be gradually more and more in demand, as people get accustomed to these coins, and begin to trust them as carriers of value. One may envision hybrid coins denominated at various values up to $100, and even up to $1000. Of course, the higher the denomination, the more sophisticated the anti-counterfeit technology involved.
[0120] There are likely to be cases where a common service, like a train ride has a non-round cost, say $23.72. If the number of commuters is large, then riders will be invited to purchase coins denominated exactly for $23.72 cents, and hand them over or slip them in a payment slot in a fast flow through to the train. The train authorities will engage the mint, to issue gold coins for this particular amount. A rider who accumulated these coins and for some reason stopped using the train, could readily use these coin for any other payment need, or he or she will be able to break the virginity of the coin, and upload its contents ($23.72) to their phone or PC for regular use.
Shape and Format
[0121] To extrapolate from present day nominal coins, one will opt for similar round shape and size, and such will be easier to accept and accommodate. But for reasons of storage, counting and otherwise, one can envision a variety of shapes and format. See for example the nut option ( FIG. 2 ). Of particular interest are the flat, card-like coins: they will serve as an extrapolation of the familiar credit card. We have on-card flat chip technology that could accommodate the hybrid coins. Credit-card like coins will have the advantage of a large surface area that can be used for branding, for colorful text and graphics for advertising purposes, etc.
Distribution
[0122] Because hybrid coins are meant to be easily transferable, they are naturally un-tethered to a particular owner, and if lost, anyone could find and use them. Same for theft and robbery. So much as people are reluctant to hold and be in possession of large number of cash, so they would not wish to hold a large quantity of hybrid coins. People will stuff their wallets, their glove compartment, their desk with a small amount of money in small denominations, and would probably opt for gold coins that are the easiest one to trade, and command the greatest measure of trust. Traders will get these coins in their bank; they will exchange coins in stores, and they will buy coins in automatic kiosks where they will pay with their credit card, or old fashioned cash, and receive the coins.
Life-Cycle
[0123] The hybrid coin is minted as a ‘gold coin’—virgin, pristine, and it may transact indefinitely as ‘gold’. At some point the gold coin is either returned to the mint for redemption, or it turns into a ‘silver coin’ namely a coin that has lost its virginity, and has been partially drained, which means some of its digital value has been removed from it. The silver coin may be traded as silver in which case the authenticity and the integrity of the coin is maintained by the coin valuation mechanism that keeps track over how much of the original value of the coin is still in it. For example, if a coin was minted as ‘gold’ in a $25.00 denomination, then after being traded as virgin, gold $25.00 coin, it is eventually ‘opened’ and $7.00 are paid off through the coin drainage mechanism, leaving the value of the coin at $18.00, with status ‘silver’. The silver coin may be traded about for its current face value of $18.00, and the payee will trust first the mint the issued the respective gold coin, and second, the value tracking mechanism within the coin that assures the recipient payee that he indeed receives a payment of $18.00. Eventually one of four things happens: (1) the silver coin is handed back to the mint for redemption, (2) the silver coin is drained to residual value of $0.00 and discarded, (3) the silver coin is rendered into a bronze coin, namely some non-Mint source of digital money pumps digital money into it and the residual tracking mechanism reflects this. The coin can then start to drain again, or it may be redeemed at the mint, or it may be re-pumped and re-used as above indefinitely. (4) the coin is lost, abandoned, it breaks down physically either by a blow, or by a strong force, or by getting excessively wet, or by some chemical interaction, or otherwise. Please note that if the coin is stolen, it can still be used unless it has proper security feature. Regular hybrid coins are presumed to be owned by their holder.
Purpose
[0124] The main purpose for hybrid coins is the desire to conclude a simple ordinary transaction with minimum of hassle and complexity. When you pick a daily paper at the counter, it's too much to pull out your phone hit a series of buttons, or slide the screen here and there. The newspaper may cost $2.50, and you wish to be able to pull a coin from your pocket, flip it over to the seller, pick your copy and move on. A $2.50 gold coin will be perfect for this use. The anonymity that is inherent to this use is another purpose, even for more expensive deals. You want to buy books without ‘big brother’ watching you and profiling you based on the books your buy or the movies you watch, or the food you eat, so paying with modern cash—hybrid coins seem a suitable satisfactory solution. Hybrid coins may prove useful in an Internet cafe and otherwise for online purposes. Of course in this use the gold coin must be broken-in, and used as a reservoir of bit money. One would expect Internet Cafe operators to hold a supply of hybrid coins for customers, who may even buy them with credit card, counting on the hope that the cafe owner is not keeping tab of which coin went to which customer. A third purpose is to avoid the burden of carrying a heavy load of regular cash in your pocket. Hybrid coins may carry a large denomination on a single coin, which is not feasible with regular coins. A fourth purpose is to avoid currency exchange when you cross a national border. The bits are usable online from any place, from any location. And so even local brick and mortar stores who may not legally and conveniently accept dollars in a foreign country, will gladly accept bit representation of dollars because it is tradable all over.
[0125] A special purpose of the hybrid coin will be as a silver category over-distance payment. See below.
Online-Offline Interplay
[0126] It seems essentials to be able to shift from online mode to offline mode and vice versa in a seamless way. Using bronze coins a trader could replenish his original coin but decrease its security and therefore make the trade with the coin a bit more cumbersome as the recipient needs to verify the paid coin. Every coin may be opened, broken-into, (disrupting its virginity), and its content may be streamed into any phone, pc, or otherwise an electronic container from where this money can be used in any online application. So bronze coin trading allows for a back and forth flow of bits without any limitation. When trade is limited to gold and silver coins then the flow of hybrid coin money is only one way: towards the online use.
Security
[0127] Security of gold coins may be assured by simple visual inspection, or by use of some authentication technology to be applied to the coin. Coins of low denominations will be inspected quickly and visually, but coins of high denominations might attract more scrutiny, and the payee may wish to use a verifier device before he or she is convinced of the gold status of the coin. Silver coins may be trusted by the coin declaring itself silver and proclaiming the value of the residual money in it. But one might expect some payee being extra cautious, especially for coins of large denominations: they will wish to authenticate the coin contents at the mint. To do that they will have to connect the silver coin to a phone or a PC. Of course “live hybrid coins” that are continuously connected to the mint are an easier option.
Power Supply
[0128] Gold coins may not require any power supply, but silver and bronze coins may be needing a power source to operate. The power may be coming partly from an outside source to which the coin is connected. In that case the silver and bronze coins will be blind—showing no indication as to how much money is left and even not as to their status, silver or bronze. They will have all that data in their ‘blind memory’ and when connected to a phone a PC or any other well powered computing device their data will be read and displayed on the connecting device. Otherwise silver and bronze coins may operate with a battery that would power the computation needed for it status determination (silver or bronze) and for computing its residual digital money. Power is also needed to display the residual money value and its status. The battery that supplies this power may be built in, and its power rated to be sufficient for the expected life time of the coin. If the built-in battery dies, the coin can be returned to the mint for replacement. Otherwise the battery may be snapped in and out, and easily replaced.
Coupons and Non-Dollar Representation
[0129] The hybrid coins may be issued to represent value other than US dollar or other national currency. Much as digital money may reflect any valuable, so is the case for hybrid coins. So hybrid coins may represent discount money in selected store, or money that is tied for a purpose, say food. One might find the coin-like appearance of the hybrid coin more appealing than the traditional cards or printed rolls of paper.
Acceptability
[0130] Acceptability of hybrid coins will probably be tied to the acceptability of the underlying digital money, and will be much appreciated as an extension thereto.
[0131] Over-Distance Payment Use Options:
[0132] Silver coins fitted with over-distance payment options may find a variety of important use cases. Over-distance payment may be carried out via NFC, Bluetooth, IR, or any other electromagnetic radiation regimen. Payment will be possible as an alternative to physical hook-up or swipe option, but also for new uses. For example an over-distance silver coin could replace today ‘Easy-Pass’—the payment devices that are attached to the windshield and communicate with road-side or road-top readers to accomplish a toll payment for a tall road, for example. A silver coin will use the over-distance technology to actually send over the money owed, as a cash transfer, instead of accounting data for a future payment. Drivers would like this, because these silver coins can be purchased everywhere, and because drivers would be able to make a payment but maintain their anonymity.
[0133] Movie goers will be able to put in their shirt pocket an over-distance payment silver coin, and never stand in line to buy a ticket, but rather walk directly to the theatre, a door-placed reader will extract the ticket amount as they walk in.
[0134] In a restaurant a diner will place a silver coin on the table, and the waiter will point to it a hand held payment extractor, and get paid.
[0135] Parking may be paid by simply displaying the silver coin on the dashboard. Every parking stop will have a distant money reader instead of the old fashioned money collector.
[0136] A special case of over distance payment refers to internet live, or phone connection, which allows for coin verification in real time, and long distance coin payment.
Hybrid Coins Use in Emergency Payment Circumstances
[0137] We consider two categories of emergencies:
networks emergency liquidity emergency
[0140] The former refers to a situation where the global or zone connectivity is disrupted, the cloud collapses, connection with the mint or its agencies is broken, and normal network enabled communication are not feasible. The latter case refers to a crisis or a disaster situation where the banks are dysfunctional, people cannot retrieve and activate their money assets, and the area is hard hit by an earthquake a powerful storm, flood, or snowfall, or perhaps a terrorist act. Areas of urban populations present a big challenge to the rescue operation and a lot depends on mutual help. Yet, one cannot expect a gas station owner to pump gas to his customers and rely on them showing up to pay for the gas when the flood is over. Cash money activates the community and allows for useful trade to help resolve the situation.
[0141] Networks emergency can clearly be helped by trading gold coins, but also by trading silver coins where the coin is battery operated, and so is the recipient of the money bits, if they are transferred to him or her. One prepares for such emergency with plenty of stored batteries.
[0142] Liquidity emergency may be handled by the disaster management authority (DMA) by distributing gold hybrid coins to the suffering population. A proper distribution of denomination previously prepared by the DMA will greatly alleviate the situation. People will then be able to trade these coin in a silver status, using the accompanied supply of batteries. This situation calls for preparation of active digital coins to be so distributed. Another, more sophisticated way to handle payment regimen in a crisis situation is to use hybrid coins of crisis money. Crisis money is money that comes alive when a disaster happens, and it fades away after the disaster is over.
[0143] Hybrid Coins for Crisis Money:
[0144] Payment requirement in a crisis situation may be handled by using ephemeral money. Ephemeral money is money that appears at a given moment—out of thin air, and at a subsequent moment it vanishes into complete disappearance. Between this birth and death points the money is active, traceable and satisfies a requirement set upon it. In general ephemeral money may vanish in a way that its holder is simply losing it. In that case the purpose of the ephemeral money is to effect some lasting changes during its live time, but the trade is such that whoever is left with it at its vanishing point, is losing its value without compensation. Such ephemeral money is used in money games and game-trades designed for digital money. But for crisis management the planned ephemeral money will be traded against some form of lasting money so that the holder of ephemeral money will end up with an equivalent or corresponding amount of durable, and lasting money.
[0145] Ephemeral money may be traded in a form of digital money prepared in hybrid coins which may or may not be distributed ahead of time. Unlike nominal money, ephemeral money is of no value until the proper authority announces its “birth”. So unlike regular money the people who receive it to prepare for a pending crisis cannot use it before its birth date, and so it will be available to them when the crisis hits. If the ephemeral money in hybrid coins is distributed through a proper range of denominations with a proper amount of coins then the coins can be traded as ‘gold’ which is the least time consuming under the duress of the crisis. Otherwise, using battery operated devices, if necessary, the people affected by the crisis will be using silver coins for their trade.
[0146] When the crisis is over the ephemeral money may be traded against nominal money under some exchange protocol. This is important for the people to be willing to accept the ephemeral money. The crisis management authority may deduct the value of the originally distributed ephemeral money from any amount of ephemeral money that people will submit for redemption. If people in the crisis zone will end up with less money than they were given then per an authoritative decision, either the shortfall will be forgiven or it will become debt to the government. Either way the ephemeral money will relieve the banks from the requirement to struggle to remain open despite the crisis, and at the same time it will allow the many strangers in the disaster zone to cooperate and collaborate in ways that would encourage many to work their hardest, and be recognize for their efforts.
[0000]
Table of Contents
Off-Line Digital Money
# 3
Introduction
# 4
The Hybrid Coin Concept
# 43
string inside hybrid coin
# 44
string not inside coin hybrid
# 5
Technology of Hybrid Coins
# 53
Mint Assurance
# 533
Cryptographic Window Mint Assurance
# 54
Virginity Assurance
# 55
Silver and Bronze Coin Value determination.
# 56
Construction Technology
# 6
Use of Hybrid Coins
# 63
use of fast common cash transactions
# 633
Over-distance payment use options
# 64
hybrid coins use in emergency payment circumstances
# 643
Hybrid Coins for Crisis Money
LIST OF DRAWINGS
[0147] FIG. 1 : string inside and string outside trading options for hybrid coins.—demonstrating the distinction between passing a string that is contained inside a hybrid coin, and a string that is without.
[0148] FIG. 2 : Anatomy of Hybrid Coin Payment environment: Depicting the functional elements in a hybrid coin payment environment.
[0149] FIG. 3 : Appearance of a hybrid coin: depicting the front and rear elements typical of a hybrid coin, including coin-id, and a running meter of residual digital value. | This invention describes a set of related procedures designed to co-operate with mints of digital money in order to allow for said money to be properly, securely, and conveniently traded by, various size and various type of trading crowds. The procedures refer mainly to distribution of responsibility. This invention also specifies the construction of digital coins encapsulated in a physical housing to amount to off-line tradable digital coins. | 6 |
[0001] This application claims the benefit of Provisional Application Nos. 60/629,026, file Nov. 18, 2004 and 60/714,809, filed Sep. 7, 2005.
BACKGROUND OF THE INVENTION
[0002] The invention relates to paperboard or paper packaging coated with aqueous polymer emulsions with food-release properties and oil and grease repellency.
[0003] Paper-based clamshell packages designed for the delivery of fast foods, such as hamburgers and fish sandwiches are conventionally extrusion coated or laminated with polymers such as polyethylene or other thermoplastic material. The plastic acts as a water, oil/grease, and moisture barrier and provides a smooth surface so that the moist food product is released intact and less likely to stick to the paper. These barrier and release properties are necessary to maintain the integrity of the packaging and ultimately the integrity of the packaged food item in such a way that the food keeps the optimum form for presentation to the customer. Water vapor transmission barrier (WVTB) is also important in these packaging applications. The retention of the water vapor released from the food needs to be retained within the package in order to keep the food hot.
[0004] Oil and grease repellent (OGR) barrier properties are also necessary because of the oil and grease contained in the food, e.g. french fries, hamburger patty and condiments. Fluorochemicals have been used in the past as a benchmark coating for OGR properties. Although fluorochemicals are an excellent OGR barrier, they are not effective as a release coating when the food items such as a bun or bread is steamed instead of toasted before packaging. Steamed buns or breads such as warm moist breads, buns, wraps, pocket breads and fried potatoes such as french fries tend to stick to the packaging paper or paperboard thereby losing their integrity. The soft bread or bun surfaces of microwaved sandwiches, wraps and pocket breads also have a tendency to stick to paper or paperboard packaging. Polylaminated paper or paperboard are not an ideal solution since the cooling bun/ food generates a vapor which condenses onto the laminate surface and causes the bun or food to become soggy and stick to the laminate thus tearing the bun.
[0005] There have been numerous attempts to solve the above problem. U.S. Pat. No. 4,653,685 has attempted to solve the problem by providing a plurality of serrations formed on an inner surface of the container to resist sticking of contained food portions.
[0006] U.S. Pat. No. 5,131,551 describes a tray having a series of generally concentric formed ridges to inhibit sticking of the food product to the base.
[0007] U.S. Pat. No. 5,039,003 preferably coats a paper with polyethylene or other thermoplastic material providing a smooth surface so that food product does not stick to the food when the food is pulled out or unwrapped for consumption.
[0008] The coating of paper or paperboard with styrene-acrylate copolymers is known in the literature. See for example Michelman, J. S. et al, TAPPI J., April, pages 159-163 (1989) and U.S. Pat. No. 5,763,100. Styrene-acrylate copolymers are described as having good water resistance. Also see Cooper, R., Paper Technology, (1990), 31(4), 34-36 which describes styrene-acrylate polymer emulsions as barrier coatings.
[0009] It has surprisingly been discovered that both OGR and food-release requirements of the package can be met with particular non-fluorochemical water-based emulsions of styrene-acrylate copolymers. Thus the styrene-acrylate copolymers of the invention may be used for preventing sticking of hot moist foods, especially warm, moist breads to the paper or paper-board used for wrapping or enclosing these foods. These styrene-acrylate barrier coatings can be used alone, with an emulsifying polymer and optionally other additives such as—starches, fluorochemicals, waxes or mixtures thereof to enhance other barrier properties.
[0010] This invention can be expanded to other paper-based packaging grades, such as food wraps, takeout containers for ready prepared foods, where not only OGR barrier and/or WVTB is required but also non-sticking characteristics of the package toward hot moist foods are desired.
SUMMARY OF THE INVENTION
[0011] The invention encompasses a hot moist food packaging
wherein the packaging is a paper or paperboard coated with a coating composition and the coating comprises a a water based emulsion polymer, wherein the polymer comprises
i) a copolymer formed from a (meth)acrylate monomer or monomers and a vinyl monomer or monomers to give a film-forming copolymer,
wherein the film-forming polymer is formed in the presence of a stabilizing polymer, wherein the stabilizing polymer is an acid-containing copolymer formed by copolymerizing a (meth)acrylic acid monomer or a mixture of (meth)acrylic acid monomers, and a vinyl monomer or mixture of vinyl monomers other than the (meth) acrylic acid monomer,
and ii) optionally, other additives or mixtures of additives,
wherein, the coated paper or paperboard has a bun-release rating of no more than about 3.
[0018] Preferable the bun-release rating is no more than about 2, especially less than 2, for example 1. The bun-release test is described herein.
[0019] The invention encompasses a method to impart oil and grease resistance to paper or paperboard, which comprises treating the paper or paperboard material with an effective amount of a coating composition comprising a
[0020] water based emulsion polymer, wherein the polymer comprises
i) a copolymer formed from a (meth)acrylate monomer or monomers and a vinyl monomer or monomers to give a film-forming copolymer,
wherein the film-forming polymer is formed in the presence of a stabilizing polymer,
wherein the stabilizing polymer is an acid-containing copolymer formed by copolymerizing a (meth)acrylic acid monomer or a mixture of (meth)acrylic acid monomers, and a vinyl monomer or mixture of vinyl monomers other than the (meth) acrylic acid monomer,
and ii) optionally, other additives or mixtures of additives,
wherein the coating composition is effective in imparting oil and grease resistance to the paper or paperboard material.
[0024] Preferably the emulsion polymer is in the form of a core-shell particle emulsion.
[0025] Another embodiment of the invention is a method for packaging hot moist foods comprising the steps of
a) coating a paper or paper-board container or wrapper with a coating composition comprising
a water based emulsion polymer comprising
i) a copolymer formed from a (meth)acrylate monomer or monomers and a vinyl monomer or monomers to give a film-forming copolymer,
and
ii) optionally, other additives or mixtures of additives,
b) drying the coating and c) contacting the hot moist food with the coated paper or paperboard container or wrapper,
wherein the food may be heated in the coated paper or paperboard or alternatively the food may be heated then wrapped in the coated paper or paperboard.
[0035] The invention also embodies a method of releasing hot moist food from the surface of paper or paperboard, wherein the method of releasing the hot moist food comprises the steps of
a) coating a paper or paperboard with a coating composition comprising
a water based emulsion polymer, wherein the polymer comprises
i) a copolymer formed from a (meth)acrylate monomer or monomers and a vinyl monomer or monomers to give a film-forming copolymer, and ii) optionally, other additives or mixtures of additives,
b) drying the coating, c) contacting the coated paper or paperboard with the food and d) removing the coated paper or paperboard from contact with the said food.
[0045] A third embodiment of the invention is a method for packaging hot moist foods in paper or paperboard and maintaining the temperature of these food items during delivery wherein the method of packaging and maintaining the temperature of the food comprises the steps of
a) coating a paper or paperboard with a coating composition
a water based emulsion polymer comprising
i.) a copolymer formed from a (meth)acrylate monomer or monomers and vinyl monomer or monomers to give a film-forming copolymer,
and
ii) optionally, other additives or mixtures of additives,
b) drying the coating and c) wrapping or enclosing the hot moist food with the coated paper or paperboard container or wrapper, wherein the food may be heated in the coated paper or paperboard or alternatively, the food may be heated then wrapped or enclosed in the coated paper or paperboard.
[0055] Another embodiment of the methods above further include the film-forming polymer being polymerized in the presence of an stabilizing polymer, wherein the stabilizing polymer is an acid-containing copolymer formed by copolymerizing (meth)acrylic acid monomer, and a vinyl monomer other than the (meth)acrylic acid monomer. Thus the water-based emulsion polymer comprises both the film-forming copolymer and a stabilizing polymer.
[0056] In the methods described above the food may be heated first then placed in contact with the paper or paperboard. Alternatively, the food may be heated within or on the paper or paperboard. The end result is the hot moist food does not stick to the paper when an attempt is made to unwrap the food.
[0057] The methods and coated paper or coated paperboard composition described above are especially valuable when used for packaging foods such as hot moist breads, buns or potatoes ensuring that paper used in wrapping hot moist foods or microwaved foods do not stick to the food and cause breakage and fragmentation.
DETAILED DESCRIPTION OF THE INVENTION
[0058] The present invention provides a coated paper or paperboard for packaging hot moist foods, a method for packaging hot moist foods, a method for releasing hot moist foods from paper or paperboard and a method of imparting oil and grease resistance to paper or paperboard. In each embodiment the paper or paperboard is coated with an aqueous emulsion containing a styrene-(meth)acrylate-resin. The coated paper is used in packaging applications where not only water and oil and grease repellency and/or water vapor transmission barrier are required but food-release properties are necessary. For example, the coating may be applied to the interior of a clamshell package to provide the required food-release property.
[0059] For the purposes of the invention, the food-release property is defined as the non-sticking property of the coated paper or paperboard that prevents the sticking of the warm moist foods. The moist food is preferably a bread, bun, pocket bread or food-wrap which when moist and warm has a tendency to stick to paper or paperboard. The bread has a tendency to fragment upon attempts to remove the paper from the bread.
[0060] The aqueous emulsions providing the correct properties for OGR and bun-release contain an effective amount of a film-forming polymer prepared by emulsion copolymerizing of a (meth)acrylate monomer or monomers with a vinyl polymerizable monomer or monomers to give the film-forming property. The film-forming polymer is preferably polymerized in the presence of a stabilizing polymer formed from an acid-containing polymer made by copolymerizing (meth)acrylic acid and a vinyl polymerizable monomer other than an acid containing monomer. The emulsion copolymerization of the film-forming polymer in the presence of the stabilizing polymer gives a core-shell particle emulsion. The core comprises the film-forming polymer. The shell comprises the stabilizing polymer. The resulting core-shell particles form a stable aqueous emulsion.
[0061] The aqueous emulsions may be used for OGR applications without the addition of fluorochemicals. Surprisingly the emulsion provides high oil and grease repellency when the paper or paperboard is treated with an effective amount of the aqueous emulsion. For example when the emulsion polymer is used in about 20 to about 40 percent solids and preferably at about 30 to about 40 percent solids, effective oil and grease repellency is observed.
[0062] This oil and grease repellency may be increased by the addition of a second aqueous solution polymer. For example, copolymers of methacrylate and/or methyl methacrylate with acrylic acid or methacrylic acid may be used to increase the oil and grease repellency. These copolymers are usually for example in the form of a salt which salt may be an alkali or ammonium salt.
[0063] The average molecular weight of the second aqueous solution polymer is in the range of about 2,000 to about 30,000, preferably in the range of about 5,000 to about 15,000.
[0064] The second aqueous emulsion polymer may be added at about 1 wt. % to about 10 wt. % of the first emulsion polymer but preferably it is added at about 2 wt. % to about 5 wt. % of the first emulsion polymer. This weight percent is based on dry-to-dry weight.
[0000] The Film-Forming Polymer
[0065] Water based dispersions or emulsion coatings used in paper-based packaging applications ideally are film-forming or in other words provide a continuous pinhole-free polymer film. One useful measure of the film-forming characteristics is the glass transition temperature (Tg) of the constituent polymers, an important measure of the flexibility of the barrier film. In packaging applications the barrier coating needs to be flexible to prevent crease and fold failures.
[0066] Another commonly used test for the film-forming characteristics is the “minimum film forming temperature” (MFFT) defined as the minimum temperature at which the dispersed polymer particles coalesce and start to form a continuous film.
[0067] The film forming polymer formed from the combination of (meth)acrylate and vinyl monomers are capable of forming a copolymer of glass transition temperature (Tg) below 50° C., preferably below 30° C.
[0068] The glass transition temperature (Tg) for a polymer is defined in the Encyclopedia of Chemical Technology, Volume 19, fourth edition, page 891, as the temperature below which (1) the transitional motion of entire molecules and (2) the coiling and uncoiling of 40 to 50 carbon atom segments of chains are both frozen. Thus, below its Tg a polymer would not exhibit flow or rubber elasticity.
[0069] The Tg of a polymer may be determined using Differential Scanning Calorimetry (DSC).
[0070] The MFFT temperature is determined by ASTM method D2354-98 and is properly applied to the emulsion. Thus the MFFT temperature applies to the coating system and includes other components not just the film-forming copolymer referred to above.
[0071] For the purposes of the invention, all styrene based copolymers with alkyl(meth) acrylates giving a Tg of less than 50° C., preferably less than 30° C. could be used as the styrene-acrylate film-forming polymer.
[0072] The (meth)acrylate monomers used to form the film-forming polymer are for example selected from the group consisting of n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, hexyl (meth)acrylate, isopropyl (meth) acrylate, decyl or lauryl (meth) acrylate, t-butyl (meth)acrylate, isobutyl(meth)acrylate, ethyl (meth)acrylate, glycidyl (meth) acrylate, hydroxyalkyl (meth) acrylates and dicarboxylic ester monomers such as maleates and propyl (meth)acrylate. The preferred (meth)acrylate monomers are n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and t-butyl (meth) acrylate or mixtures thereof.
[0073] The vinyl polymerizable monomer or monomers of the film-forming polymer are selected from the group consisting of methyl (meth)acrylate, isobutyl (meth)acrylate, styrene, and styrene derivatives such as α-methyl styrene, alkylated styrene and mixtures thereof. The preferred vinyl polymerizable monomer or monomers are methyl methacrylate, styrene or alkylated styrene.
[0074] The vinyl polymerizable monomer for the film-forming polymer is a monomer such as those described above which do not contain an acid functionality such as (meth)acrylic acid. In particular, styrene, α-methyl styrene and alkylated styrene are preferred.
[0075] The weight ratio of the (meth)acrylate monomers to vinyl polymerizable monomers in the film-forming polymer ranges from about 30/70 to about 70/30, preferably the weight ratio of (meth)acrylate monomers to vinyl polymerizable monomers is about 35/60 to about 60/35. Most preferably the weight ratio is about 40/60 to about 60/40 based on the total weight of the film-forming polymer.
[0076] For example, the film-forming polymers of the invention include
50 weight % n-butylacrylate and 50 weight % styrene, 45 weight % n-butyl acrylate and 55 weight % styrene, 40 weight % 2-ethylhexyl acrylate and 60 weight % styrene, 40 weight % 2-ethylhexyl acrylate and 30 weight % methyl methacrylate and 30 weight % styrene. 45% weight % 2-ethylhexyl acrylate and 55% weight % styrene.
[0082] Each of these examples gives a low Tg (under 50° C.) and are film-forming. For example, a 55/45 styrene 2-ethylhexyl acrylate give a Tg of ˜22° C.
[0083] The average molecular weight for the film-forming polymer ranges from about 150,000 to about 350,000 g/mol determined by GPC. Preferably the polymer has a molecular weight of about 200,000 to about 300,000 g/mol. More preferably the optimum molecular weight for the matrix polymer is about 200,000 to about 275,000 g/mol.
[0084] In order to obtain an aqueous dispersion from these vinyl monomers, it suffices to perform an emulsion polymerization of the monomers by well-known methods to produce a stable dispersion using hydrophilic catalysts, such as ammonium persulfate, potassium persulfate or aqueous hydrogen peroxide, or redox catalysts.
[0085] A mixture of vinyl monomers may be copolymerized in the emulsified state in the presence of anionic or nonionic surfactants to provide an emulsifying agent. In general, the use of low molecular weight surfactants is known to adversely affect the water and water vapor repellency of the coating formed, so that anionic polymeric stabilizers are preferred. These polymeric stabilizing agents may be exemplified by aqueous solutions of conventional alkali-soluble resins, such as acrylic or methacrylic or maleic copolymers containing carboxylic acid groups.
[0000] The Stabilizing Polymer
[0086] The preferred stabilizing polymer present during the polymerization of the film-forming polymer is made by co-polymerizing (meth)acrylic acid, and a vinyl polymerizable monomer other than an acid monomer to form a copolymer of a glass transition temperature (Tg) that ranges from about 50° C. to about 120° C., preferably from about 70° C. to about 120° C. and most preferably the Tg ranges from about 80° C. to about 110° C.
[0087] The vinyl polymerizable monomer or monomers of the stabilizing polymer contain (meth)acrylic acid and a vinyl monomer other than the acid monomer. At least one of the vinyl monomers is preferably selected from the group consisting of styrene, alkylated styrene, α-methyl styrene, butyl (meth)acrylate, methyl (meth)acrylate and mixtures thereof.
[0088] The stabilizing polymer is an acid containing polymer made by copolymerizing (meth)acrylic acid, and a vinyl polymerizable monomer other than the (meth)acrylic acid and is formed from about 10 to about 50 weight % acrylic acid, methacrylic acid or mixtures, preferably about 10 to about 45 weight % and about 90 to about 50 weight % of a vinyl polymerizable monomer other than the (meth) acrylic acid monomer, preferably about 90 to about 55 weight %. The monomer percentages are based on total weight of the polymer.
[0089] Examples of appropriate stabilizing polymers are
65% styrene and 35 % acrylic acid; 43% isobutyl methacrylate, 43% methyl methacrylate and 14% acrylic acid; 43% butyl acrylate, 43% methyl methacrylate and 14% acrylic acid; 80% ethylene and 20% acrylic acid;
[0094] The salts of the stabilizing polymer may be any salt as long as the polymer maintains it's emulsifying properties. Preferably, the polymer is a volatile salt, for example an ammonium salt.
[0095] The shell polymer or stabilizing polymer has a molecular weight of about 6,000 to about 15,000 g/mol. Preferably the polymer has a molecular weight of about 6,000 to about 12,000 g/mol. Most preferably, the polymer has a molecular weight of about 6,000 to about 10,000 g/mol.
[0096] Generally the average particle size diameter of the particles is less than about 300 nanometers. Preferably the average particle size diameter is in the range of about 200 to 60 nanometers and especially between 150 and 60 nanometers. Average particle size is determined by a Coulter particle size analyzer according to standard procedures well documented in the literature.
[0097] A suitable technique for initiating the polymerization is, for instance, to elevate the temperature of the aqueous emulsion of monomer to above about 70 or 80° C. and then to add between 50 and 1000 ppm of ammonium persulfate or an azo compound such as azodiisobutyronitrile by weight of monomer. Alternatively, a suitable peroxide, e.g. a room-temperature curing peroxide, or a photo-initiator may be used. It is preferably that the initiator be water-soluble.
[0098] It is preferred that the particles have a core-shell configuration in which the core comprises the film-forming polymer surrounded by a stabilizing polymeric shell. More preferably the particles comprise a core comprising the film-forming polymer and a shell comprising the water-soluble or partially water-soluble stabilizing polymer. It is particularly preferable that the shell of the water-soluble or partially water-soluble polymer is formed around the core of film-forming polymer and during polymerization.
[0099] The core-shell polymer is provided in an aqueous emulsion and may include other additives such as thickening agents, defoaming or antifoaming agents, pigments, slip additives, release agents, fluorochemicals, starches, waxes and antiblocking agents. Components such as fluorochemicals, starches and waxes can also be added to improve oil, grease and other barrier properties such as water repellency and water vapor transmission barrier.
[0100] The wax component may be selected from the group consisting of paraffin wax, candelilla, carnauba, microcrystalline wax, polyethylene wax and a blend of two or more of said waxes. The combination of the styrene-acrylate emulsion with wax is particularly preferred since when this coating is used on the paper or paperboard, not only does the paper or paperboard provide food-release properties but also helps to maintain the temperature of the food enclosed or wrapped in the paper or paperboard. While not wanting to be limited by any theories, it is believed that the combination of the styrene-acrylate emulsion and wax prevents the water vapor from escaping the package. The retention of the warm vapor within the packaging helps to maintain the temperature of the warm food. The combination of styrene-acrylate emulsion coating with the wax helps maintain the warmth of the food and prevents the warm food from sticking to the paper.
[0101] Starches may also be added to the food release coating.
[0102] Typical sources of starches include cereals, tubers, roots, legumes and fruits. Native sources can be corn, pea, potato, sweet potato, banana, barley, wheat, rice, sago, amaranth, tapioca, arrowroot, canna, and sorghum.
[0103] Useful starches may also include modified versions of any of the aforementioned starches. Modification may be accomplished via physical or chemical substitution on the base starch. Further, more than one type of modification may be used on a single base starch. As used herein, modified starches include, without limitation, crossliniked starches, stabilized starches (i.e., starches which do not undergo retrogradation under freeze-thaw conditions), acetylated and organically esterified starches, hydroxyethylated and hydroxypropylated starches, phosphorylated and inorganically esterified starches, cationic, anionic, nonionic, and zwitterionic starches, and succinate and substituted succinate derivatives of starch. Such modifications and combinations thereof are known and their preparation are described in the art. See, for example, Whistler, R. L., BeMiller, J. N. and Paschall E. F., STARCH CHEMISTRY AND TECHNOLOGY, 2.sup.nd Ed., Academic Press, Inc., London, Chpt. 9, sctn. 3, pp. 324-349 (1984) and MODIFIED STARCHES: PROPERTIES AND USES, Wurzburg, O. B., Editor, CRC Press, Inc., Florida (1986).
[0104] The amount of starch used in the food-release coating normally ranges from 0% to 10% by weight of the total coating formulation. The preferred starches are hydroxyalkylate corn starches such as hydroxyethylated and hydroxypropylated corn starches.
[0105] Examples of likely ethoxylated corn starches available commercially are Coatmaster K56F, from Grain Processing Corp. (Muscatin, Iowa), Ethylex 2075 from A. E. Staley Mfg. (Decatur, Ill.), Filmkote 85:54 from National Starch and Chemicals (Bridgewater, N.J.), Penford Gum 270 from Penfort Products Co. (Cedar Rapids Iowa). An example of likely ethoxylated potato starch is Solfarex A-55 supplied by Avebe America Inc.
[0106] The use of perfluoroalkyl-substituted compounds to impart oil and grease repellency to paper substrates is well known in the art. For paper treatment the most important products have traditionally been phosphate diesters of a perfluoroalkylalkanol or diperfluoroalkyl-substituted carboxylic acids, as described in U.S. Pat. Nos. 4,485,251, 4,898,981, 5,491,261 and 6,436,235 herein incorporated by reference. These compounds are applied by rollers, a size press or other means to the finished paper as a coating. Copolymers of poly-perfluoroalkyl (meth)acrylates may also be used as external paper sizes since polymers provide the extra benefit of water resistance which is a desirable feature in many food packaging and fast-food applications.
[0107] U.S. Pat. No. 3,083,224 also incorporated by reference discloses certain polyfluoroalkyl phosphates, which are also useful in imparting oil repellency to paper and textile materials.
[0108] The amount of perfluorinated compounds used in the coating composition ranges from 0% to about 1% by weight based on the dry weight of the coating. The effectiveness of the perfluorinated compound for OGR performance will depend upon the total amount of fluorine incorporated into the coating. Preferably the range of the perfluorinated compound varies from 0% to 0.3% based on the dry weight of the coatings.
[0109] The formed coating emulsion or food release coating composition including the core-shell polymer, and additives is generally anywhere from about 30 to about 60 % solids based on the total weight of the emulsion. Preferably the solids range from about 40 to about 50 % solids based on the total weight of the emulsion.
[0110] The weight ratio of the film-forming polymer and the stabilizing polymer in the emulsion range from about 40 to 80 weight % film-forming and about 60 to 20 weight % stabilizing polymer; preferably the film-forming polymer and stabilizing polymer range from about 50 to about 80 weight % film-forming and about 50 to about 20 weight % stabilizing polymer based on the total weight of the film-forming and stabilizing polymer.
[0111] Substrates employed in the invention include a variety of coated and uncoated paper and paperboard, including bleached or unbleached, hardwood or softwood, virgin or recycled, coated or uncoated forms of paper or paperboard. The basis weight of the substrate ranges from 20 to 450 g/m 2 . Preferable range of basis weight is about 35 to about 70 g/m 2 .
[0112] The water based emulsion coatings of the invention have dry coating weights in the range of about 1 to about 10 g/m 2 . Drying temperatures and line speeds are dictated by the drying characteristics of specific coating formulations, for example the % solids content, substrate basis weight and adsorbency, and equipment characteristics. For example for hot, moist food applications where bun release properties are needed, the coating weights will generally range from about 1 to about 5 g/m 2 and preferably about 1 to about 3 g/m 2 if fluorochemicals are added.
[0113] When the polymer emulsion is used for OGR applications, an effective coating weights will generally range from about 2 to about 9 g/m 2 and preferably about 2 to about 6 g/m 2 . For example, a coating weight of about 2 g/m 2 or greater is needed to obtain effective oil and grease repellency.
[0114] The base paper of OGR applications preferably has a basis weight of at least about 30 g/m2. Preferably the paper has a Parker Print Surf Smoothness below about 4 micrometers (μm). Preferably the Gurley Porosity is >10 seconds and most preferably equal to or greater than 100.
[0115] The Parker Print Surf Smoothness and Gurley Porosity are well known in the art and may be determined using TAPPI methods T-555 om-99 and T-536 om-96 respectively.
[0116] Effective oil and grease repellency for the purposes of the invention is a value of one-half hour for the Turpentine test (see TAPPI T454 om-94 below) or a value of less than about 5 % according to the RALSTON-PURINA test (see RP-2 below).
[0117] The RP2 Test is a pet food test. Pet food is far more oil aggressive than human food and so a treated substrate that works well for RP2 test will work well of human food.
[0118] The water-based emulsion coatings of this invention may be applied to the surface of the substrate by any method of coating suitable for water-based coatings. Examples of suitable surface treatment methods include various conventional coating methods such as air knife coating, blade coating, metering roll coating, rod coating, curtain coating, spray coating, injet printing, flexo and gravure coating, size press applications and water box.
[0119] Generally some type of elevated temperature drying will be required in order to dry the water based emulsion coatings at an acceptable production speed. Suitable drying methods include hot air drying, infrared drying, direct flame drying and drying by contact with a steam roll.
[0120] The example below illustrates the invention and is not meant to limit the scope and spirit of the invention in any way.
[0121] Formation of the Core Shell Polymer
EXAMPLE 1 Monomer Feed Styrene 1294 g 2-ethylhexyl acrylate 1058 g Reactor Charge 65/35 styrene/acrylic acid 988 g copolymer as ammonium salt Water 3497 g 1 TETRALON B 1.5 g Reactor initial Initiator charge Water 23 g Ammonium Persulphate 3.4 g Initiator Feed 210 g Water Ammonium Persulphate 9 g Monomer Feed line flush Water 50 g Post additions 2 ACTICIDE LG 7 g Water 130 g
[0122] The monomer feed is added to the reactor over 3 hours and initiator feed is added over 4 hours. The reactor is maintained at 85° C. throughout polymerization.
[0123] A styrene/2-ethylhexyl acrylate film-forming copolymer is formed in the presence of the stabilizing 65/35 styrene/acrylic acid polymer and results in a core-shell polymer that is approximately a 46% solids emulsion. The composition of the particles is 70 parts styrene/2-ethylhexyl acrylate copolymer (55/45) core and 30 parts (65/35) styrene/acrylic acid shell. The particle size of the core-shell is typically about 80 nm to about 120 nm.
1. TETRALON B is a sequestering agent. 2. ACTICIDE LG is a biocide.
Application Testing
[0126] The bun-release and oil kit below are preformed using the 46% solids emulsion of example 1. Various formulations using the emulsion are listed below in table 1. All numbers are based on weight % of the total emulsion unless otherwise specified.
TABLE 1 Application Testing No. 1 2 3 4 5 6 7 8 9 10 11 Example 1 15 10 10 10 7.5 7.5 0 0 25 20 15 1 Starch 5 5 6.5 6.5 7.5 7.5 7.5 7.5 0 0 0 2 LODYNE 2000 0 0 0 0.125 0 0.125 0 0.25 0 0 0 Total wt. % solids 20 15 16.5 16.625 15 15.125 7.5 7.75 25 20 15 Total Solid Coat wt. (g/m2) 2.11 1.50 1.85 1.95 1.49 1.52 0.88 0.81 2.41 1.94 1.43 3 Dry Coat wt. of core-shell polymer (g/m2) 1.58 1.00 1.12 1.18 0.74 0.75 0.00 0.00 2.41 1.94 1.43 1 Hydroxy ethoxylated corn starch supplied as COATMASTER K56F, from Grain Processing Corp. (Muscatin, Iowa). 2 Fluorinated amphoteric organic acid ammonia salt. Supplied by Ciba Specialty Chemical Corp, Tarrytown, NY. 3 The dry coating weight is based on the 46% solids emulsion formed in example 1 after drying.
Bun Release Test
[0127] Sheets of 50 g/m 2 basis weight paper are size press coated in the lab with the formulations above and placed on the interior bottom of McDonald's clamshells. Pairs of McDonald's hamburger buns, crowns and heels, were steamed in a steam chamber for two minutes, and a pair of bun crown and heel is then placed upside down in the clamshell in direct contact with the treated side of the paper sample. A 50 ml beaker with 65 g of sand (to simulate the weight of an assembled hamburger) is placed on top of the bun and the clamshell is closed and placed into a heating chamber at 180° F. for two minutes. The clamshell is removed from the heating chamber and the bun crown is gently pulled from the test paper. The ratings go from 1 indicating no sticking, to very slight sticking up to a rating of 7 which represents tearing of the moist bun.
[0000] Oil Kit Test
[0128] The oil repellency of the surface is determined by using the TAPPI UM 557 OIL KIT TEST, which consists of determining which of twelve castor oil-heptane-toluene mixtures having decreasing surface tension penetration occurs within 15 seconds; ratings go from 1, lowest, up to 12.
TABLE 2 Application Testing No. 1 2 3 4 5 6 7 8 9 10 11 Oil kit 4 1 2-3 3 1 1-2 0 8 4 3 2 Bun 1 2 1 1 7 1 7 4 1 1 1 Release Ratings
Oil and Grease Repellency (OGR) Testing of Paper Coatings
[0129] Coatings for the OGR testing are made up at 30 and 40 percent solids based on total weight from the emulsion formed in example 1. Examples 13-15 are formulated with an additional 4 percent second solution polymer solids (dry-to-dry in relation to the emulsion of example 1). The coatings are applied by a filmpress applicator. Drying is carried out by hot air or IR at coating speeds of approximately 100 meters/min. The rod pressures are adjusted to obtain different coat weights. The coating weights are determined gravimetrically.
[0130] The base paper is 38 gsm (grams/m 2 ) for candy-wrap applications.
[0000] Oil and Grease Resistance Tests
[0000] RALSTON-PURINA (RP2) Test
[0131] Grease resistance is determined with the RALSTON-PURINA test for pet food materials; RP-2 Test, Ralston-Purina Company, Packaging Reference Manual Volume 06, Test Methods. In summary: cross-wise creased and uncreased test papers are placed over a grid sheet imprinted with 100 squares. For the crease test five grams of sand are placed in the center of the crease. A mixture of synthetic oil and a dye for visualization is pipetted onto the sand and the samples are maintained at 60° C. for 24 hours. Ratings are determined by the percentage of stained grid segments, using at least two samples. The uncreased test is identical to the creased but the paper is not creased.
[0000] Turpentine Test
[0132] According to TAPPI T454 om-94, a preliminary test to determine rates at which oil or grease can be expected to penetrate the paper. Table 2 below presents a summary of these results.
TABLE 2 Grease and Oil Repellency Resulta RP-2 Turpentine Uncreased Uncreased Creased Creased Wt % Coat wt. Test 1 2 1 2 EX Solids [g/m 2 ] [hr] [%] [%] [%] [%] 2 40% 3 2.50 1.1 1.4 1.9 7.4 3 40% 4.5 6.00 3.3 0.3 4.1 2.2 5 40% 4 6.00 0.4 1.1 5.3 6.7 6 40% 5 24.00 9.0 3.2 48.2 3.1 7 30% 1.5 0.50 1.6 1.9 5.3 6.7 8 30% 2 1.00 2.1 2.4 14.2 9.9 9 30% 2.5 1.50 1.4 5.6 100.0 13.5 10 30% 1 0.50 1.6 2.0 7.4 4.3 11 30% 2 0.50 0.8 4.7 16.7 4.2 12 30% 3 4.00 0.7 3.1 6.7 7.1 13 40%+ 1 3 0.05 0.1 48.0 4.8 9.1 14 40%+ 4 1.50 0.1 0.1 3.3 3.4 15 40%+ 6 24.00 0.1 0.3 8.7 4.2 16 0 0.00 100.0 100.0 1 The coatings for examples 13-15 also include 4% based on dry weight to total coating weight of an aqueous solution copolymer of methyl acrylate/methylmethacrylate/acrylic acid, 65/25/10 ammonium salt. | The invention is directed to hot moist food packaging, a method for packaging the same, and a method to impart oil and grease repellency to paper or paperboard. The compositions and methods are especially valuable when used for packaging foods such as hot moist breads, buns and oily starchy foods such as potatoes. The compositions and method ensure that the paper in contact with the food does not stick to the bread bun or starchy foods and cause breaking or fragmentation. | 3 |
BACKGROUND OF THE INVENTION
RELATED APPLICATIONS
There are no applications related hereto now filed in this or any foreign country.
FIELD OF INVENTION
My invention relates generally to a splint for human appendages and more particularly to a leg splint that is adjustable extensible, especially during use.
DESCRIPTION OF PRIOR ART
In the medical and surgical arts it is oftentimes necessary to immobilize a limb of a patient, especially as in the treatment of fractures, and many splint type structures have heretofore become known for such purposes. The instant invention is such a splint, particularly for use during emergency treatment and patient transport, that provides potentiality for adjustable extension of the supported limb.
In the initial treatment of fracture type injuries of a human limb it is ordinarily desirable to immobilize the injured member, especially during transport of the victim and before a permanent fixation of the member. It again is desirable, if not necessary, to maintain the limb with some extension or to at least prevent any contraction of the muscles in it to alleviate pain and prevent further tissue or skeletal damage. If the limb should be set where complete surgical facilities are not available it is also desirable in the fixation process prior to the traditionl casting operation to maintain the portion of the limb about the injured area in extension. The instant invention seeks to provide apparatus having the potentiality for accomplishment of procedures of this type.
Heretofore splint devices performing at least one of the recited functions have become known and in some instances a combination of more than one of the functions have been performed by a single device. Specifically, rigid peripheral frame splints having at least two parts articulately joined have become known and these joined parts have been so articulated as to allow extension of the peripheral frame and thus establish the potentiality for establishing extension in a limb to be supported. It has become known to provide a splint with a configuration and adjustable parts that will adapt it for use on either a human arm or leg, and such multiple use splints are common in present day medical arts. It has also become known to use a pneumatic cylinder carried by a splint frame to contain and substantially imobilize a portion of a traumatized limb in a pressured fashion that tends to lessen the pain and swelling in the member during containment. The instant invention differs from this prior art by providing a splint embodying all of these features in combination and so particularized that each is operative with the others to provide functions in such combination that are greater than the total of those provided individually.
Specifically, my splint provides a sliding connection between rigid peripheral frame elements with associated mechanical screw means of extending one element relative the other to allow frame extension that is positive, easily controllable and accomplished with minimal effort. I provide an adjustable frame which, aside from its extensible features, allows adjustment of the frame members to accommodate limbs of various sizes and proportions and yet maintains its required rigidity. My splint further provides a pneumatically inflatible annular cylinder, carried by the peripheral frame for limb containment, that is completely openable and positively closable by a zipper type closure. My splint provides particularly configured end structures that may be adapted for use with either an arm or a leg on either side of the body. I also provide an open type structure that allows use of the splint frame during the setting operation on a limb by maintaining portions of the limb on opposite sides of a broken bone in extension while yet giving access about the area of the break for application of cast material.
SUMMARY OF INVENTION
My invention comprises generally an articulated peripheral splint frame carrying a medial limb restraining element.
The peripheral frame comprises opposed elongate side bars joined at their ends by cross elements, each side bar being formed with two parts extensibly joined to each other with associated screw means to extend one part relative the other. The cross member in the distal portion of the splint frame is compound and extensively joined in fashion similar to the side bars to allow lateral adjustment of the space between the two side bars. The medial, limb restraining element is an annular cylindrical structure, fastened along diametrically opposed lines to the side bars of the peripheral frame and providing a zipper type closure of the cylinder along a side element. The structure is formed of elastically resilient material to define an enclosed pneumatic chamber about a medial limb enclosing space. Limb fastening straps are provided at both distal and proximal ends of the peripheral frame to fasten that part of the splint about adjacent limb structure. Plural intermediate fastening straps are provided to encircle the side bars of the splint frame and the medial limb restraining element to aid in positionally maintaining that limb restraining element in the splint.
In creating such a splint it is:
A principal object of my invention to provide a splint with peripheral frame formed of compound elongate elements that may be mechanically adjusted to provide positive extension of the frame to allow potential extension of a supported limb.
A further object of my invention to provide such a splint that has a pneumaticly inflatible limb restraining element of annular cylindrical shape to support a traumatized limb with some pressure over a substantial area adjacent the traumatized portion to alleviate some pain and swelling.
A further object of my invention to create such a splint that has plural medial limb support bands to allow a limb to be maintained in extension in the device without enclosure by the pneumatic limb restraining element, so that the splint may be used during traditional setting operations.
A still further object of my invention to provide such a splint that is adjustable as to size to allow use with a range of limb sizes and configurations.
A still further object of my invention to provide such a splint that is of new and novel design, of rugged and durable nature, of simple and economic manufacture and otherwise well suited to the uses and purposes for which it is intended.
Other and further objects of my invention will appear from the following specification and accompanying drawings which form a part hereof. In carrying out the objects of my invention, however, it is to be understood that its essential features are susceptible of change in design and structural arrangement with only one preferred and practical embodiment being illustrated in the accompanying drawings, as is required.
BRIEF DESCRIPTION OF DRAWINGS
In the accompanying drawings which form a part hereof and wherein like numbers of reference refer to similar parts throughout:
FIG. 1 is an isometric view of the principal species of my invention showing its various parts, their configuration and relationship.
FIG. 2 is an enlarged, partial cross-sectional view, of the valve device of FIG. 1 taken on the line 2--2 thereon in the direction indicated by the arrows to show the details of the valving structure.
FIG. 3 is a transverse, cross-sectional view of the device of FIG. 1 taken on the line 3--3 thereon in the direction of the arrows to show internal structural details of the limb restraining element.
FIG. 4 is a transverse, cross-sectional view through the proximal cross-member of the device of FIG. 1 taken on the line 4--4 thereon in the direction indicated by the arrows.
FIG. 5 is an enlarged partial elongate cross-sectional view of a side rod joint of the device of FIG. 1 taken on a line 5--5 thereon in the direction indicated by the arrows.
FIG. 6 is an isometric view of a species of my splint having only strap elements to support a limb therein.
FIG. 7 is an enlarged, partial, cross-sectional view of the joint in the outer cross member of the device of FIG. 6 taken on the line 7--7 thereon in the direction indicated by the arrows.
FIG. 8 is a transverse cross-sectional view of the device of FIG. 6 taken on a line 8--8 thereon in the direction indicated by the arrows to show particularly the detailed structure of a limb fastening strap.
FIG. 9 is an orthographic view of the proximal end of the device of FIG. 6 from a viewpoint looking outwardly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As seen especially in FIG. 1, my invention generally provides rigid, articulating peripheral split frame 11 carrying elongate limb restraining cylinder 12 and plural fastening straps 13.
The terms `inner` and `outer` as used in describing an end or end portion of my invention refer respectively to the end of the splint normally adjacent the most proximal part of a serviced limb and that normally adjacent the most distal part thereof. In FIGS. 1 and 6 the `inner` end is at the right of the drawings.
Rigid peripheral frame 11 provides similar compound opposed cooperating side rods, having outer portion 14 and inner portions 15 articulately communicating with each other, joined at their inner ends by inner cross member 16 at their outer ends by outer cross member 17, 18. Preferably, though not necessarily, the frame provides in its outer end, on the side opposite cross member 17, 18 compound outer support 21, 22 structurally carried by outer end portion 14 of the side rods.
The configuration of the articulating joinder of side rods 14, 15 is shown in FIG. 5 where it is seen that outer portion 14 comprises a larger tubular element and inner member 15 a smaller rod like element so configured that portion 15 is carried within the channel defined by outer portion 14 in a slidable fit such that the two members may be moved relative each other by manual manipulation. Outer end portion 19 of inner member 15 is threaded for some distance and carries adjustment nut 20 in threaded engagement thereon so that the nut is rotated to move outwardly, inner side rod will be extended from the outer side rod 14 to cause extension of the end parts of the splint frame relative to each other. The length of the threaded portion of the outer end part of inner side rod 15 determines the amount of this extensive movement and obviously it may be nearly as long as the length of outer side rod 14.
A similar type of slidable articulating joinder is provided between outer cross member elements 17, 18 and outer support elements 21, 22; each smaller element 17, 21 is provided with threadedly engaged adjustment nuts 23, 24 to provide for lateral adjustment of the outer end part of the peripheral frame structure to accommodate various limb proportions and sizes.
Inner cross member 16 is preferably formed as a relatively flat element of appropriate cross sectional area to provide the physical rigidity and strength required of it and is mechanically joined to the inner end parts of opposed inner side rods 15 by mechanical means, preferably by riveting, as illustrated.
These rigid frame members of my splint are constructed from some sufficiently rigid, relatively light, durable material, preferably a metal such as aluminum or one of its alloys. Some plastic polymeric materials are operative for this purpose but in general those that have appropriate physical characteristics are too expensive to be economically feasible in creating a structure compatible with present day economics.
Limb restraining element 12 provides elongate, annular, cylindrical body 25, openable along one linear element by means of traditional zipper 26, and carrying opposed, cooperating frame connecting flaps 27 along diametrically opposed linear surface elements. Body 25 defines internal limb chamber 28 configured of appropriate size and shape to contain a size range of limbs. The body is formed as a double wall structure as shown especially in FIGS. 2 and 3, with plural internal separators 29 extending between opposed walls to define pneumatic chamber 30 comprising a totally enclosed chamber for containment of pressurized gas. As seen in FIG. 2, normally closed, manually and pressurably openable pneumatic valve 31 communicates from the exterior surface of body 25 to pneumatic chamber 30 to allow filling of the chamber with a pressurized gas and its deflation as required. This particular valve structure is of the type well known in the pneumatic arts. The material from which body 25 is formed is elastically resilient so that the structure, when placed about a limb to be immobilized may be inflated with pressurized gas to conform to the irregular surface of that limb carried therein, exert some pressure on the adjacent surface of that limb and maintain the limb in a supported, substantially immobile condition. The material ideally suited for this purpose and the one preferred by me is rubber, though undoubtedly other materials of the same nature, such as polymerixed plastics, would fulfill the purpose of my invention if not so well.
Frame connecting flaps 27 provide web 32 extending normally outwardly on each side from body 25 on the limb restraining element and defining in their outward portion an elongate side rod channel 33 of a size appropriate to allow outer side rod 14 to slidably pass therethrough with no more resistance than can be conveniently overcome by manual force. The limb restraining element is carried with the peripheral frame side rods in the side rod channels as illustrated in FIGS. 1 and 3. It is discontinuous over the length of body 25 to allow appropriate voids or notches therein adjacent side rod adjustment nuts 28 to allow appropriate motion of those nuts for required frame adjustments.
Fastening straps 13 maintain the splint in proper position on the body of a user and maintain a supported limb in proper position in the splint. Inner fastening strap 34 extends from structural joinder with the inner end of one inner side rod 15 to associated buckle 35 which structurally communicates with the opposed inner end of the other side rod. This strap has some length so that a limb to be supported may be supported upon inner cross member 16 with inner fastening strap 34 extending thereover to maintain the supported limb between the strap and cross member.
At the outer end of splint frame 11 flexible, strap like limb rest extends between the outer end parts of opposed outer side rods 14 to cooperate with outer support strap 37 to hold the distal part of a limb therebetween. The ends of outer limb rest 36 are mechanically fastened by riveting or similar means, to frame 11. One end of outer strap 37 is fastened to one side of the outer end portion of the splint frame preferably on one outer cross member 17, 18. The medial portion of the strap carries frictional type fastening buckle 38 so that the free end of the strap may be passed about the side of the splint frame opposite that to which it is connected and thence passed through buckle 38 to be fastened between the two outer cross members.
Medial fastening straps 39 are elongated, flexible elements carrying fastening buckles 40 at one end and having appropriate length to extend and be bastenable completely around the splint frame and limb restraining element to aid in fastening and maintaining the limb restraining element in proper position relative the frame when it is supporting a traumatized limb, especially as during transport.
Any or all of the fastening straps may have associated with them various padding and force distributing devices 41 common in the splinting arts to distribute pressures over wider areas and prevent irritation to and pain in adjacent body parts. These padding devices may be formed as an integral part of the fastening straps or may be separate and maintained thereon as desired. The fastening straps themselves are preferably formed of some reasonably flexible strong material, commonly a webbed belt fabric that is sufficiently pliable to conform to the surface contours of an adjacent supporting surface.
The species of my invention shown in FIG. 6, et seq., does not have the medial pneumatic limb restraining element, but rather only medial fastening straps somewhat modified from those principal species. This species of the invention is simpler to operate and less expensive to manufacture, and is particularly adapted to expose traumatized portions of a limb for casting while yet maintaining the limb in extension.
The basic frame of the device is the same as previously described for the primary species of my invention except an additional medial cross element 42 has been added extending between and structurally communicating with the inner end parts of outer side rods 14 to provide some additional lateral support and rigidity for this form of my invention. This cross support, again, is formed from semi-rigid strap material, preferably metal, and if so formed is preferably covered with padding of some soft pliable material. The cross member is attached to the side rods by mechanical joinder preferably by welding as illustrated. This cross piece must be somewhat flexible to allow any lateral adjustment of the outer end of the frame. Use of the cross piece is convenient but not necessary to this species of my invention, but if it be not used the splint frame is obviously the same as in the principal form.
Medial fastening straps 39 with associated buckles 40 are the same as in the principal species of the invention but each in addition has associated with it supporting straps 43 which are fastened in a band like configuration over and about the opposed side rods 14, 15 in the loose fashion illustrated, with ends fastened together and to the strap body so that the supporting strap is maintained between the frame side elements but slidable there along for lineally adjustable positioning. Each medial support strap cooperates with the associated medial fastening strap to maintain and support a limb therebetween with some force, depending upon the adjustable tension between the two straps and the size of the supported limb.
Having thusly described my invention its operation may be readily understood.
To use the principal species of my invention a splint is formed according to the foregoing specification and the various fastening straps and the limb restraining element opened. The splint is then positioned so that the limb to be supported is in the limb restraining element 12 with its traumatized portion medially located within that element. Inner fastening strap 34 is then placed over a proximal portion of the limb to be supported and fastened tightly enough to provide appropriate engagement with the portion of the limb inward of the tranumatized area. Outer fastening strap 37 is similarly fastened about the adjacent distal portion of the traumatized limb. Adjustment nuts 20 are manipulated rotatably to cause extension in the portion of the limb between the inner and outer fastening straps 34, 37. This extension is accomplished because the limb is maintained at both the inner and outer end parts of the splint by the inner and outer fastening straps and since extensive motion of the peripheral frame 11 occurs responsive to rotary motion of the adjustment nuts the limb between its supported points must necessarily be extended. Obviously for accomplishment of such limb extension the force exerted upon the limb by inner and outer fastening straps must be appropriate to prevent motion of the limb relative thereto. With such small force as is required to cause extension, however, this fastening may be readily accomplished by ordinary manual manipulation.
After the limb is placed in appropriate extension, pneumatic restraining element 12 is replaced over the upper portion of the limb to be supported and zipper 25 is fastened to provide a cylindrical structure about the traumatized area. The restraining element is then inflated with pressurized gas to an appropriate pressure of some few pound per square inch to exert some force on the contained limb but yet not cut off circulation in it or do other physiological harm. Medial fastening straps 39 are then fastened about the inflated restraining element to provide additional support of that element within the rigid peripheral frame and in this condition the contained limb is substantially immobilized and the patient may be readily transported for treatment. Normally the pneumatic pressure in the limb restraining element required to immobilize a limb and provide some pain relief is relaively small and may be provided by mouth. Higher pressure, of course, may be readily provided by any of the various pneumatic devices common in todays marketplace for dispensing pressurized gas. After inflation of the limb restraining element and if that inflation be sufficient the inner and outer limb restraining elements may be loosened or unfastened especially if they tend to disrupt normal or desirable biologic activity in the traumatized limb.
The species of my invention described is used in the same fashion as described for the principal form of the invention except that there is no pneumatic bag to completely contain the supported portion of a limb and the part of the limb about the traumatized portion may be readily worked upon while it is contained in the supporting splint. It should be noted that with the species of my invention that the medial supports may be variously positioned as desired along side rods 14, 15 to allow access to any particular portion of the limb where access may be desired, especially as for reduction and splinting.
The foregoing description of my invention is necessarily of a detailed nature so that a specific embodiment of it might be set forth as is required, but it is to be understood that various modifications of detail, rearrangement and multiplication of parts may be resorted to without departing from its spirit, essence or scope. | A splint for human appendages, particularly the legs, providing an articulating peripheral frame carrying a medial limb supporting element. The peripheral frame is adjustable for lineal dimension by positively acting screw means. The ends of the splint have straps for fastening to adjacent body parts to allow extension of the limb between splint ends during use. The limb support element of a species of the splint is a zipper closed pneumatic cylinder. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §119(e) to provisional patent application Ser. No. 60/218,486 filed Jul. 14, 2000, the disclosure of which is hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
N/A
BACKGROUND OF THE INVENTION
Structured finance is a financing technique whereby specific assets are placed in a trust, thereby isolating them from the bankruptcy risk of the entity that originated them. Structured finance is known to be a market in which all parties rely to a great extent on the ratings and rating announcements to understand the credit risks and sources of protection in structured securities (of which there are many types, asset-backed commercial paper (ABCP), asset-backed securities (ABS), mortgage-backed securities (MBS), collateralized bond obligation (CBO), collateralized loan obligation (CLO), collateralized debt obligation (CDO), structured investment vehicles (SIV), and derivatives products company (DPC), synthetic CLOS, CBOs of ABS, collectively “structured finance.”) Currently, the credit quality of securities issued in connection with structured financings are determined at closing by comparing the amount of enhancement in a given transaction relative to the estimated portfolio variability of losses over the effective life of the transaction. However, these ratings are rarely, if ever, updated to reflect actual experience. Accordingly, a method is desired for dynamically updating the credit rating of structured securities based on actual credit loss and other performance.
Structured financings are typically the result of the sale of receivables to a special purpose vehicle created solely for this purpose. Securities backed by the receivables in the pool (“asset pool”) are then issued. These are normally separated into one or more “tranches” or “classes”, each with its own characteristics and payment priorities. Having different payment priorities, the tranches accordingly have different risk profiles and payment expectations as a function of the potential delinquencies and defaults of the various receivables and other assets in the pool. The senior tranche usually has the lowest risk.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to a method for calculating and dynamically updating the credit quality of securities issued in connection with structured financings. Said credit quality is measured as a deviation from the relevant payment promise with respect to said securities. Such a deviation can occur when, for a variety or reasons, the assets do not generate sufficient cash flows to reimburse the investors in full, interest and principal.
In this method, data representing the structure of the transaction and data representing the current state of the asset pool are used. A Markov chain formalism is used with respect to the received data to predict the cash flows likely to be received from the asset pool. Cash flows generated by the Markov chain model are applied to the liabilities according to the exact payment priority set out in the transaction documents. This priority may include features such as triggers, insurance policies and external forms of credit enhancement. Accordingly, this method models performance of the structured security based on the cash-generating capacity of individual exposures.
Other aspects, features and advantages of the present invention are disclosed in the detailed description that follows.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The invention will be more fully understood by reference to the following detailed description of the invention in conjunction with the drawings, of which:
FIG. 1 is a flow chart for the structured finance performance index calculation method according to an embodiment of the present invention;
FIG. 2 illustrates a Markov state transition matrix for a structured financing transaction according to an embodiment of the present invention;
FIG. 3(A) illustrates an example of a credit loss base curve for an asset of unknown character and seasoning pattern with multiple curves showing the local variability of credit losses;
FIG. 3(B) illustrates a credit loss base curve for an automobile loan securitization, or the expected case in a rated transaction with multiple curves showing the local variability of credit losses;
FIG. 3(C) illustrates a dynamic credit loss base curve for a performing auto loan securitization according to an embodiment of the present invention with multiple curves showing the local variability of credit losses;
FIG. 3(D) illustrates the deviation from the payment promise for transactions with improving performance according to an embodiment of the present invention; and
FIG. 4 illustrates a computer system for performing the method according to embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A flow chart is illustrated in FIG. 1 for a method of calculating the deviation from a payment promise associated with a structured financing that may be characterized by an asset pool and one or more liability tranches according to an embodiment of the present invention.
In the present calculation method, two distinct processes are performed. The first process is performed either at closing or during the closing time period of a transaction. The second process is performed every subsequent time period until the lower of the average maturity of the asset pool or the point at which the securities have matured or been retired. The time period is measured in accordance with market customs and is typically one month. A more detailed description of the processes for the method in the present embodiment follows with reference to FIG. 1 .
The present method begins by reading various data and variables associated with the transaction at step 100 . These data will be used to compute the performance-monitoring index. The data and variables read at step 100 include data such as basic transaction parameters (interest rates, etc.), liability structure information, initial asset pool information such as the number of accounts and average quantities, initial tranche ratings as assigned by rating agencies, and specific Markov-process based parameters and deal information on which the performance monitoring index is based. The data are read in from various sources and data providers.
FIG. 2 illustrates an example of a Markov matrix having the new status corresponding to columns 0 , 1 , 2 , 3 , 4 and 5 of the matrix, and the old status corresponding to rows 0 , 1 , 2 , 3 , 4 and 5 of the matrix. The value of cell c 00 of this matrix corresponds to the probability of an account remaining in state 0 at the end of a time period given that it was in state 0 at the beginning of the period. Beyond cell c 00 , and moving to the right, each cell value represents the probability of a periodic transition from state 0 to a further delinquency condition, worsening as we move right across columns. In other words, the value in each cell corresponds to the probability that an account will move to a delinquency status indicated by the column heading given a starting position measured by the row number. In any row of the Markov matrix, the sum of the probabilities must equal one by definition. Typically, the last two cells in a row correspond to default and prepayment transition probabilities, respectively. Also, a non-zero probability cannot practically exist in more than one cell to the right of the diagonal from cell c 00 , c 11 , . . . due to timing conventions (i.e. it is physically impossible for an account in any delinquency status to become delinquent by more than one additional time period in the span of a single time period).
To determine the status-wise probability distribution of the accounts in the asset pool for the first period after closing of the transaction, a row matrix V it is used. This matrix represents the initial probability distribution of the accounts in the transaction. The Markov matrix (P) is pre-multiplied by the row matrix (i.e. V it *P) to compute the new status-wise probability distribution of accounts after the first time period. Generally, the probability distribution of the accounts for any period, n, in the future is given by the equation V it *P n . Further, the cash flows associated with a given time period are derived from the change in the probability distribution of accounts between two consecutive time periods using the credit policies in force for the assets underlying the transaction. These policies are available from one or more parties to the transaction.
The entries of the Markov matrix at each time step are computed with reference to a credit loss base curve characteristic of the relevant asset class derived from issuer data. The parameters of the known base curve, in conjunction with random deviates issuing from specified probability distributions with parameters defined by the base curve, are used to modulate one or more entries of the Markov matrix at each time period to reflect expected cash flow dynamics.
Referring again to FIG. 1 , a determination is made at step 110 as to whether we are at either the closing or during the closing month for the transaction. If the current period is the closing period, a “sigma” calibration is performed at step 120 for the transaction. The purpose of this calibration is the determination of the volatility of asset performance necessary to cause the senior tranche of the transaction to display the deviation from its payment promise corresponding to the credit rating assigned to it by the rating agencies that have rated the transaction. This calibration is accomplished via a Monte Carlo simulation that utilizes the Markov chain formalism and is performed using the exact liability structure of the transaction. After each Monte Carlo run, the above volatility is modified in such a manner as to take the senior tranche payment promise deviation closer to that implied by its credit rating. This process is continued until convergence. The result of the calibration is the standard deviation of asset performance implied by the senior tranche credit rating assigned to the transaction by the rating agencies. A by-product of these calculations is the peformance monitoring index for the other tranches of the transaction computed in the same manner, i.e. as a deviation from their payment promise.
Once the calibration has converged at step 125 , initial performance monitoring index values for each tranche are output at step 130 . By construction, the senior tranche rating is identical to the agency's rating. In general, the lower rated tranche classes will have different ratings from the rating agencies as the present method uses an objective and unique numerical scale for each letter-grade rating category (Aaa, Aa, Baa, etc.). As a result, the performance monitoring index values generated by the present method for all lower tranches will not necessarily agree with the corresponding letter-grade credit rating assigned to them by the rating agencies. The calibrated sigma is then stored at step 135 for later use in updating the performance monitoring index value for each tranche at each time period.
Data for any later period are input at step 140 from commercially available databases that aggregate transaction information based on trustee and servicer reports. This occurs during the second and each subsequent period.
Current deal performance is compared to expected performance at closing and differences are used to adjust Markov chain parameters at step 150 . These updated Markov matrices are then handled via the same process of multiplying them in succession with a row matrix V it from period two to maturity. Specifically, the defining parameters of the credit loss base curve are modified with reference to the difference between expected and actual performance. This updated base curve is then used within the Markov chain formalism described earlier to re-compute the performance-monitoring index in the same manner. Variables such as delinquencies, defaults and pre-payments may be used in the adjustments. A number of ad-hoc adjustment processes may be substituted for the ones normally employed based on the needs of particular investors or issuers. For instance, more emphasis may be placed on defaults (e.g. with automobile loan assets) or on pre-payments (e.g. with mortgage assets).
The performance-monitoring index is then computed at step 170 for the relevant time period. Prepayment assumptions based on commercially available codes and approximations may be input at step 160 for integration into the computation performed at step 170 . The Markov chain formalism is capable of interfacing with most conventional pre-payment models.
The prepayment probability is normally the second to last entry in the first row of the Markov matrix. It is referred to as the single month mortality (“SMM”) by prepayment modelers. Under the present invention, the SMM definition excludes pre-payments that originate from obligors in delinquent states. Commercially available SMM values are typically given on a dollar rather than an account basis, but the difference between the dollar and account values is generally small compared to the accuracy of most commercially available prepayment models. These models may be integrated with the Markov chain formalism described herein by inserting SMM values in the appropriate cell of the matrix.
In computing the performance monitoring index value at step 170 , the data from the pre-payment models input at step 160 and the standard deviation computed at step 135 are utilized.
The performance-monitoring index is output at step 180 so that users may receive and display the generated information.
A general idea of the concepts underlying the performance-monitoring index described herein may be obtained by reference to FIGS. 3(A)-3(D) . In FIG. 3(A) , a credit loss base curve is shown for an asset of unknown character and seasoning pattern, and with multiple curves meant to convey the local variability of credit losses. In FIG. 3(B) , another credit loss base curve is shown for an automobile loan securitization, or the expected case in a rated transaction, and with multiple curves meant to convey the local variability of credit losses. The implied rating agency credit loss base curve analysis presented in FIG. 3(B) is contrasted with results obtained in each corresponding period at step 170 of the method for the present embodiment of the invention as shown in FIG. 3(C) . The conventional analysis connected with FIG. 3(B) is not adjusted for incremental information available on the transaction, whereas the expectation as illustrated in FIG. 3(C) is adjusted by the method described according to the present embodiment.
Contrast, further, the analysis shown in FIGS. 3(B) and 3(C) with the analysis shown in FIG. 3(A) , where seasoning effects are not considered. In the case of performing pools, the method according to the present embodiment reflects the fact that the credit loss volatility of these pools will decrease as time passes, causing a corresponding improvement in the average credit quality of the securities backed by it. In other words, as loss volatility decreases with the passage of time, the expected deviation from the payment promise narrows, as shown in FIG. 3(D) . In particular, the top curve in FIG. 3(D) illustrates exemplary loss volatility at the time of closing and the bottom curve of FIG. 3(D) illustrates exemplary loss at some time after closing. In the top curve, the area under it and to the right of line 2 (the enhancement to cushion pool level losses) represents pool credit loss values that will cause losses on the securities backed by it. These latter losses can be measured in yield reduction from the payment promises. The updated analysis shown by the bottom curve, and taken some time after closing, shows a negligible reduction of yield, having negligible area to the right of line 2 .
According to the embodiments of the present invention, a performance-monitoring index is provided for periodically assessing the deviation from a payment promise associated with a structured financing, using updated asset pool performance data as it becomes available so that the performance monitoring index may be dynamically updated during the life of the transaction. The performance-monitoring index uses a Markov chain formalism to predict and adjust the prediction of future cash flows generated by the asset pool to service the securities and adjusts the loss estimate based on current information from the subject asset pool as it becomes available. The performance-monitoring index models the precise liability structure of the transaction in a cash flow framework. Thereby, the performance-monitoring index is able to determine the deviation from a payment promise, normally measured as a loss in basis point yield, on each of a plurality of tranches based on their contractual payment characteristics.
The invention is typically performed in a powerful computer environment given the number of times the basic matrix calculations are performed. As such, one or more CPUs or terminals 410 are provided as an I/o device for a network 412 including distributed CPUs, sources and internet connections appropriate to receive the data from sources 414 used in these calculations as illustrated in FIG. 4 in an embodiment of the present invention.
It will be apparent to those skilled in the art that other modifications to and variations of the above-described techniques are possible without departing from the inventive concepts disclosed herein. Accordingly, the invention should be viewed as limited solely by the scope and spirit of the appended claims. | A method for assessing and dynamically rating transactions ( 180 ) for structured finance transactions. The method assesses the deviation ( 170 ) from a payment promise to be expected from securities backed by pools of assets of various forms ( 100 ), the securities being issued in a plurality of tranches ( 125 ). The liabilities of the transaction, including triggers and external form of credit enhancement, are taken into account precisely to compute the deviation from the payment promise to be expected by liability holders. Data representing the structure of the transaction and the current state of the asset pool are received ( 100 ). A Markov chain formalism ( 150 ) is applied on the received data, and a cash flow model is constructed to predict the cash flow performance ( 180 ) of the asset pool. | 6 |
FIELD OF THE INVENTION
The present invention is directed to an internal burner for thermal spraying of powdered material by a supersonic flame jet from an oxy-fuel, or air-fuel mixture combusted in a combustion chamber of an internal burner and expanded to atmospheric or lower pressure through a nozzle coupled to the internal burner combustion chamber, or from a plasma heat source, and more particularly to lowering of the jet temperature to below the melting point of the material being sprayed such that the material is rendered solid prior to impact on a substrate or workpiece with an appreciable temperature increase corresponding to the kinetic energy expended by the high velocity particles impacting on the surface of the substrate or workpiece to effect particle fusion.
BACKGROUND OF THE INVENTION
It is known from U.S. Pat. No. 2,861,900, issued Nov. 25, 1958, entitled "JET PLATING OF HIGH MELTING POINT MATERIALS", that particles can be heated to high temperatures by being entrained in the combusting mixture and in the jet flame with an appreciable temperature increase corresponding to the kinetic energy expended upon the impact of the high velocity particles upon the surface of the workpiece to be coated sufficient to ensure a firm mechanical bond with the surface of the workpiece.
In my U.S. Pat. No. 5,120,582, issued Jun. 9, 1992, entitled "MAXIMUM COMBUSTION ENERGY CONVERSION AIR FUEL INTERNAL BURNER" and in my U.S. Pat. No. 5,271,965 entitled "THERMAL SPRAY METHOD UTILIZING IN-TRANSIT POWDER PARTICLE TEMPERATURES BELOW THEIR MELTING POINT", unlike U.S. Pat. No. 2,861,900, the particles are fed into the jet stream downstream of the throat of an elongated expansion nozzle having a L/D ratio of least 3:1 to prevent clogging of the nozzle bore.
In U.S. Pat. No. 5,271,965 there is particular emphasis on impact fusion, i.e. the method of producing a coating by impacting high-velocity solid (plastic) particles against the surface in which the released impact energy raises the particles to their melting point. In that application, it is noted that "impact fusion" is best carried out by injection of the powder being sprayed into a supersonic jet stream of a static temperature less than that of the melting point of the powder being sprayed. For example, operating an oxy-fuel internal burner at a combustion pressure of 300 psig produces a 6,700 ft/sec jet with a static temperature of 2,750° F. For powdered materials of high melting point, the criterion for "impact fusion" is met. But, for a metal such as aluminum with a melting point of about 1,200° F., particle melting limits the accelerating nozzle length to less than that required to reach maximum particle velocity. However, my U.S. Pat. No. 5,120,582 teaches in certain examples that combustion pressure increases may be achieved in a simple manner using compressed air and fuel oil in place of propane such that, for a combustion pressure of 1,200 psig, the supersonic jet stream reach fully expended velocities in the range of Mach 4.5 (7,400 ft/sec). Such leads to particle impact velocities on substrates of over 4,000 ft/sec, and the coatings on the substrate improve in quality nearly directly proportional to impact velocity.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to provide a thermal spray method which optimizes the flame jet temperature, particularly useful for low melting point particles such as aluminum to reach maximum particle velocity, but to reduce the jet temperature to its desired value below the melting point of the particles by cooling the supersonic jet to the point where particle melting is avoided.
This invention is directed to a method of particle coating of a substrate by impact fusion thermal spraying of a powdered material by a supersonic flame jet from an oxy-fuel, air-fuel or plasma heat source and expanding the flame jet to atmospheric or lower pressure and to the improvement of lowering the jet temperature to below that of the melting point of the material to ensure that the particles of material at the moment of impact on the substrate are below their plastic temperature. The step of reducing the temperature of the jet stream to a temperature below the melting point of said material may consist in injecting directly into the jet stream an amount of liquid coolant capable of reducing the jet stream temperature by the required amount or passing the jet through a heat exchanger capable of removing the necessary amount of heat from the jet to a coolant medium circulated through the heat exchanger. Preferably, the coolant medium is water.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic, longitudinal sectional view of an internal burner utilizing a jet cooling method forming a preferred embodiment of the invention.
FIG. 2 is a schematic, longitudinal sectional view of an internal burner utilizing a method for cooling the flame jet by liquid injection into the hot jet gases and forming an alternate embodiment of the invention.
FIG. 3 is a plot of the jet stream along the flow path within the nozzle between the combustion chamber of the internal burner and the point particle feed into the jet stream of the embodiment of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An understanding of the present invention may be obtained by reference to FIG. 1, which is a longitudinal, cross-sectional view of an internal burner providing a high temperature flame jet capable of thermal spraying of material in particle form against a substrate S. The flame spray apparatus indicated generally at 1 is principally formed by a burner body 10 of elongated cylindrical form, which is integrated to an expanding nozzle 12 and an elongated nozzle extension 13. The components 10, 12 and 13 may constitute a unitary structure, the body 10 being of larger diameter than the expanding nozzle 12 and its nozzle extension 13. The body 10 includes an upstream end wall 2 and forms a combustion chamber 11.Oxygen and fuel identified schematically by labeled arrows are introduced to the combustion chamber 11 through intersecting oxygen and fuel injection passages 15 and 16, respectively, within end wall 2. Ignition inthe combustion chamber 11 may be effected by a spark plug (not shown) or flashback from outlet 5 of nozzle passage or bore 4. The products of combustion as gas begin to expand at point a, FIG. 1, the entrance to nozzle 12 and upstream of throat 3. Full expansion with the formation of the supersonic gas flow takes place at point b.
The present invention is particularly involved with the step of cooling of the supersonic gas stream from point b to point c, which constitutes a flame jet cooling zone for the flame jet, indicated generally at J. The nozzle extension 13 is provided with a small diameter radial hole or bore 21 through which a low melting temperature material such as aluminum is introduced via a powder feed tube 22 from a source of powder as indicated by the arrow labeled "POWDER INJECTION". The particles of the low temperature melting material such aluminum enter the jet stream J and flowtherewith, generally axially within bore 4 of the nozzle extension 13, as indicated at P. It is noted that the powder injection occurs downstream ofthe jet cooling zone which terminates at c, and the nozzle exit 5 is located at d, some distance downstream from the termination of the jet cooling zone at c.
The particles P, which are maintained at a temperature below their molten state, partially by the expansion of the gases and principally by the effect of cool down of the jet stream within jet cooling zone 20, impact against the substrate S to form coating C by impact fusion. The in-transittemperature of the particles to the workpiece is held below that melting point, while the jet stream itself supplies sufficient velocity to the particles such that upon striking the workpiece or substrate S, the impactenergy is transformed into heat, thereby increasing the temperature of the particles to the fusion temperature of the particles and fusing the powdered material P to form a dense coating C on the workpiece surface. The particle are to be accelerated to supersonic velocity by being sprayedinto the flame jet.
Such apparatus and the method steps described in general, to this point is exemplified by U.S. Pat. Nos. 2,861,900; 5,120,582 and 5,271,965.
The improvement within such method involves in the embodiment of FIG. 1 thecooling of the jet within cooling zone 20. Such cooling is effected in thisembodiment by a simple heat exchanger indicated generally at H and comprised of a heat conducting tube 6, which is coiled about and in close contact with the outer periphery of the extension nozzle 13 over an axial length from b to c. The heat exchange coil 6 has an upstream inlet end 7 and a downstream outlet end 8, and a stream of liquid coolant such as water, schematically illustrated at 9, is fed into the inlet end 8 of the heat exchange tube coil 6 and exits as indicated schematically by arrow 9', the effect of which is to remove heat from the jet stream J over the full length of the heat exchanger H.
A second embodiment of the invention as shown in FIG. 2, in which the flamejet apparatus indicated generally at 1', is essentially the same as in the first embodiment with the exception of the structure employed in the flamejet cooling step, such constitutes an improvement in flame spraying of particles. Like elements in FIGS. 1 and 2 bear like numerals.
In FIG. 2, while only the downstream portion of body 10 is illustrated and only the upstream portion of nozzle extension 13 is shown, the content of that apparatus which is not shown is identical to that of FIG. 1, and a substrate or workpiece S, such as at FIG. 1, is positioned downstream of the outlet of the nozzle extension 13. In this embodiment, the products ofcombustion within combustion chamber 11 of body 10, effected by ignition ofan oxygen and fuel mixture or air-fuel mixture as in FIG. 1, exit through the expansion nozzle 12 converging at nozzle throat 3. Gas expansion begins at point a, with full expansion and the formation of supersonic gasflow of the jet J taking place at point b, or upstream thereof. Similar to the embodiment of FIG. 1, cooling is effected in a jet cooling zone 20 between points b, c. Further, powder injection is downstream of the jet cooling zone at point c with powder injection by way of the labeled arrow and the particles passing through tube 22 and a small diameter radial hole21 so as to enter and mix with the jet stream J, the particles being at P identical to that of the embodiment of FIG. 1. In this embodiment, jet cooling is effected differently from that of the embodiment of FIG. 1. Theapparatus 1' further includes a ring 26 about the outer periphery of the nozzle extension 13 which acts in conjunction with a peripheral groove 27 having an axial length less than the width of ring 26 to form an annular manifold 24. A radial hole 23 within the ring 26 forms a liquid coolant inlet passage to which a liquid such as water as indicated schematically by the arrow labeled "WATER" is fed into the manifold. A plurality of circumferentially spaced small diameter radial holes 25 are provided within the nozzle extension 13 and open up at opposite ends to the manifold 24 and the bore 4 of the nozzle extension 13 forming a part of the nozzle passage of the two-segment nozzle assembly 12, 13. Water passesradially from the water inlet passage 23 into the annular manifold 24 and radially through the small diameter injector holes 25 such that the water is injected into the supersonic jet flow stream J exiting from the expansion nozzle 12. Liquid coolant as droplets 28 disappear prior to reaching the end of the coolant zone 20 at c. The liquid coolant, preferably water, is changed to steam. It is preferred that the powder injection via tube 22 and small diameter powder injection port 21 be downstream of the point c where most of the water has changed to steam.
FIG. 3 is a plot illustrating the drop in temperature from the temperature of the products of combustion of the oxygen and fuel mixture or air-fuel mixture within combustion chamber 11 at the point a where they enter the expansion nozzle 12 and prior to reaching the throat 3 of the nozzle 12 for both the embodiments of FIGS. 1 and 2. The temperature on the plot, for the example given, is just below 5,000° F., at point a. The expansion of the combustion gases shows, in the plot, that the now supersonic jet stream temperature drops to 2,750° F. at the point bwhere the jet stream reaches the cooling zone 20. During passage through the cooling zone, the jet stream is reduced to a temperature below 1,000° F., some 200° F. below the melting point of the aluminum powder P, which powder P is injected into that jet stream via tube 22, in both embodiments. In the plot of FIG. 3, for the example given, the combustion chamber temperature is 4800° F., and the combustion pressure is 300 psig. The initial gas expansion curve from point a to point b, with a temperature drop from 4,800° F. to 2,750° F., results in a stream which is much too hot to impact fusion spray aluminum whose melting point is nearly 1,500° F. lower. The solid gas expansion curve line 31 plots the actual temperature of the jet stream as it passes through the cooling zone between points b, c, while the dash line 30 is a plot of the flame jet J temperature in the absence of water cooling.
The solid line gas expansion curve 31 is a plot of the flame jet gas temperature where, for the example given, the rate of coolant water injection via the injection ports 25 is 0.8 pounds per minute. As a result, the flame jet temperature falls to a value of approximately 900° F., which is several hundred degrees F below the aluminum melting point.
EXAMPLE I Parameters
Oxy-fuel combustion at 4,800° F. at a pressure of 300 psig.
1,800 scfh of oxygen
7 gallons per hour of fuel oil
T j , temperature of expanded jet=2,750° F. at b
V j , jet velocity=6,700 ft/sec at b combustion heat=700,000 Btu (after coolant heat losses)
assuming linear cooling relationship, a temperature reduction to 1,000° F. requires Q Btu absorption by the cooling water.
Q=WC.sub.p ΔT
Where W is weight flow of jet stream per unit time C p is the specific heat of these gases ΔT is the required temperature drop
Q=192 (0.24) (1,750)
=80,600 Btu/hr
Each pound of water requires approximately 1,000 Btu to reach the vaporizedstate. Thus, only 80 pounds of water are required per hour. This is 11/3 pounds per minute.
While the description of the preferred embodiments illustrates two modes ofcooling the jet flame prior to actual injection of the particles to be impact fused against the workpiece or substrate by a supersonic hot jet flame, the cooling of the jet flame may be accomplished by other methods. The disadvantages of external cooling requiring heat transfer through the nozzle extension 13 lies not only in the added complexity of the metal tubing in coil form or otherwise about the outer periphery of the nozzle extension 13, but the fact that appreciable heat is lost from the jet. Further, while the injected coolant is in liquid form, preferably water asillustrated in FIG. 2 for the second embodiment, any coolant may be employed capable of performing the function of adequately cooling the flame jet J over the extent of the cooling zone 20 including a compressed gas such as air. However, with water injection the total jet heat remains essentially constant with an increase in the jet mass flow.
It is envisioned additionally that cooling may be effected by the injectionof a coolant stream through one or more inlet injector holes or ports 26 inaccordance with the embodiment of FIG. 2, either radially as shown, or diagonally at a radially inward and downstream angle from a manifold such as manifold 24 by using a jet stream gaseous dilutant such as air or steam.
As may be appreciated in the embodiments of FIGS. 1 and 2, other liquids may be substituted for water, as long as they are capable of adequately removing heat from the supersonic jet stream or by vaporization therein, preferably upstream of the powder injection point C.
It should be understood that the new features of the flame spray apparatus for particle impact and fusion against the substrate as disclosed herein may be employed in ways and forms different from those of the preferred embodiments described above without departing form the spirit and scope ofthe invention, as defined by the appended claims. | An internal burner combusting an oxy-fuel or air-fuel mixture, or a plasma heat source providing a supersonic flame jet which when expanded to atmospheric or lower pressure is characterized by a static temperature well above the melting point of a material in particle form being sprayed by the flame jet and the step of reducing the flame jet temperature after reaching supersonic velocity to a temperature below the melting point of the material prior to feeding of the material particles into the flame jet. The jet temperature reduction may be effected by injecting directly into the flame jet stream an amount of liquid or gas fluid which will reduce the flame jet temperature by the required amount. Alternatively, the supersonic flame jet may be passed through a concentric heat exchanger bearing a coolant medium such as water to absorb the necessary amount of heat from the flame jet to reduce the flame jet temperature to below the melting point of the material. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to an optical fire-detector in which a radiation-emitting means is arranged to emit a beam of radiation and which has modulator means for the modulation of the beam of radiation in a phase-inverted relationship within a first and a second wavelength band and a radiation-detecting means is arranged to receive the beam of radiation after it this has passed through an intermediate air medium and includes first means for an individual measurement of the intensity in the two wavelength bands and second means for the detection of such variations in the measured intensities which are representative for a fire.
An optical fire-detector of the above defined type is described in the Swedish Patent application No. 7604502-0 where the mutually phase inverted modulation within the first and the second wavelength band is for the purpose of enabling the individual measurement of the intensity in the two wavelength bands to be carried out by means of a single radiation-sensitive element. The fire detector can obtain a good discrimination against flicker generated by the surrounding electrical illumination by a method which is described in the Swedish Pat. No. 7310965-4. According to such method the beam of radiation is emitted in the form of a series of narrow high-power pulses, the radiation-detecting means being arranged to be frequency-selective for the rise time of the pulses.
One drawback with this known method is, however, that the fire detector achieves the desired discrimination against flicker generated by the surrounding electrical illumination only if the radiation detector as well as the radiation-emitting means have a short rise time of the order of μs. Thus, this method does not enable an efficient use of such radiation-sensitive elements in which a high sensitivity is achieved at the cost of a long rise time of the order of 100 μs.
The optical fire detector according to the invention achieves a good discrimination against flicker generated by surrounding electrical illumination without requiring a short rise time neither at the radiation detector nor at the radiation emitting means and enables an improved discrimination against such flicker which is generated when mechanical vibrations for example caused by heavy street traffic vary the outgoing direction of the beam of radiation from the radiation-emitting means.
DESCRIPTION OF THE DRAWING
The invention the characteristics of which appear from the appended claims will now be described more in detail with reference to the accompanying drawing where;
FIG. 1 shows a preferred embodiment of an optical heat-detector; and
FIG. 2 shows a preferred embodiment of an optical heat- and smoke-detector.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a preferred embodiment of an optical heat-detector according to the invention. A radiation-emitting means 1 which is arranged to generate an outgoing beam of radiation comprises a sine-wave oscillator 2 arranged, to achieve via a phase inverter 3, a mutually phase-inverted modulation of the radiation intensity within a green wavelength band of a radiation contribution from a light emitting diode 4 and an infra-red wavelength band of a radiation contribution from a light emitting diode 5, respectively. A radiation detector 6 is placed at a distance from the radiation-emitting means 1 for receiving the beam of radiation after it has passed an intermediate air medium. The detector 6 comprises two photo-transistors 7 and 8 which are arranged to achieve a separate measurement of the intensity in the green and the infra-red wavelength band respectively in the beam of radiation. For this purpose a dichroic filter 9 is placed in front of the photo-transistor 7 in the path of the received beam of radiation and is arranged at an angle of 45 degrees relative this path. The second photo-transistor 8 is placed in the path of a part of the received beam of radiation reflected by the dichroic filter 9. The filter 9, which is known per se, transmits, according to the example, the green part of the beam of radiation to the photo-transistor 7 and reflects the infra-red part of the beam of radiation to the photo-transistor 8.
In the radiation-emitting means 1, a second dichroic filter 10 is placed in the path for the outgoing green radiation from the light emitting diode 4 and is arranged in an angle of 45 degree relatively this path, and the second light emitting diode 5 is placed so that its outgoing infra-red radiation is reflected by the filter 10 out into the same path as the outgoing green radiation from the light emitting diode 4. The green radiation from the light emitting diode 4 and the infra-red radiation from the light emitting diode 5 are transmitted and reflected respectively by the filter 10 substantially without any loss. There is thus a practically lossless summation of the radiation from the light emitting diodes 4 and 5.
According to the invention the radiation detector 6 comprises a demodulator 11 in which a summation means 12 according to the example has an inverting and a not-inverting input connected to the photo-transistor 7 and to the photo-transistor 8 respectively via the AC amplifiers 13 and 14 respectively. The summation means 12 produces a summation signal derived from the mutually phase-inverted modulation within the green and infra-red wavelength band in the beam of radiation from the radiation emitting means 1. The summation signal is supplied to a multiplier 15 which is arranged to shift the gain of the demodulator 11 between a positive and a negative value in synchronism with the mutually phase-inverted modulation within the green and infra-red wavelength band in the beam of radiation from the radiation emitting means 1. The utilized method for modulation and demodulation gives the demodulated summation signal the property of a good discrimination against flicker generated by surrounding electrical illumination.
According to the example the multiplier 15 has a control input connected to an output of the summation means 12 via a pulse shaping means 16. A suitable embodiment for the multiplier 15 is described in the publication Electronics, Jan. 9, 1975, p. 113. The pulse shaping means 16 consists according to the example of a voltage comparator with a grounded reference input.
The demodulator is connected to an AM-detector 17 for detection of such an amplitude modulation in the received beam of radiation which is representative for heat. For this purpose the AM-detector 17 comprises a band-pass filter which according to the example is arranged to pass the frequency interval 10-100 Hz. The AM-detector 17 is connected to a heat alarm output 18 via an integrating and threshold detecting means 19.
FIG. 2 shows a preferred embodiment for an optical heat and smoke detector according to the invention. A radiation-emitting means 20 is arranged to generate an outgoing beam of radiation. The means 20 comprises the same means as the radiation-emitting means 1 in FIG. 1, namely a sine-wave oscillator 21, a phase inverter 22 controlled by the sine-wave oscillator 21 and arranged to provide a phase-inverted modulation of the radiation intensity of a green emitting light emitting diode 23 and an infra-red emitting light emitting diode 24 and a dichroic filter 25 for the superimposing of the radiation from the light emitting diodes 23 and 24 into an outgoing beam of radiation which completely corresponds to the outgoing beam of radiation in FIG. 1.
A radiation detector 26 is placed side by side with the radiation-emitting means 20 and is arranged to receive an incoming beam of radiation generated by reflection of the outgoing beam of radiation by means of a remote reflector (not shown). The radiation detector 26 comprises, like the radiation detector 6 in FIG. 1, two photo-transistors 27 and 28, a dichroic filter 29 and a demodulator 30. In the demodulator 30 a summation means 31 is included which according to the example has two identical inputs connected to the photo-transistor 27 and to the photo-transistor 28 respectively via the AC amplifiers 32 and 33 respectively and a multiplier means 34. The means 34 includes two multipliers 35 and 36 controlled in phase with each other and arranged to shift the gain between the photo-transistors 27 and 28 and their respective connected inputs of the summation means 31 between a positive and a negative value in synchronism with the mutually phase-inverted modulation within the green and infra-red wavelength band in the beam of radiation from the radiation-emitting means 20.
According to the example the multipliers 35 and 36 have a respective control input connected to the sine-wave oscillator 21 in the radiation-emitting means 20 via a common pulse shaping means 37 which is included in the demodulator 30 and consists of a voltage comparator with a grounded reference input.
The radiation detector 26 comprises an AM-detector 38 for detection of such amplitude variations in the received beam of radiation which is representative for heat. The AM-detector 38, which according to the example is connected to the photo-transistors 27 and 28 via said multipliers 35 and 36 of the multiplier means 34 and via said identical inputs of the summation means 31, is fed with a difference signal derived from the mutually phase-inverted modulation within the green and infra-red wavelength band in the beam of radiation from the radiation-emitting means 20. The AM-detector 38 comprises besides a band pass filter for the frequency range 10-100 Hz and an amplification means for raising the signal level before detection. The AM-detector 38 is connected to a heat alarm output 39 via an integrating and threshold detecting means 40.
In the radiation detector 26 the summation means 31 is further connected to a smoke alarm output 41 via an integrating and threshold detecting means 42 which thus is fed with the same difference signal as the AM-detector 38. The polarity of the difference signal for the smoke alarm is normally predetermined but if this is not the case then threshold detection can be carried out by means of a window comparator for which a suitable embodiment is described in Electronics, Sept. 5, p. 113-114.
In the heat and smoke detector in FIG. 2 the function for the heat alarm as well as for the smoke alarm is based on the experience that fire influences a beam of radiation to a different degree within two different wavelength bands and therefore can be detected by a difference measurement. This principal function enables providing a heat and smoke alarm with a very good discrimination against flicker generated by surrounding electrical illumination and gives furthermore a good discrimination against such flicker which is generated when mechanical vibrations caused by, for example heavy street traffic, vary the outgoing direction of the beam of radiation from the radiation emitting means 20.
The invention is not limited to the described embodiment but can be modified in many ways within the scope of the appended claims. For example, the photo-transistors 7 and 8 in FIG. 1 and 27 and 28 in FIG. 2 can be of photo-darlington type with two or even three transistor elements thanks to the fact that the utilized principle for modulation and demodulation enables a good discrimination against flicker possibly generated by surrounding electrical illumination also at a lower modulation frequency for example of the order of 1 kHz. This means that the entire rise time is allowed to amount to the order of 100 μs. The integrating and threshold detecting means 19 in FIG. 1 and 40 in FIG. 2 can be provided with such means for a more effective heat detection which are described in the German Pat. No. 2 051 640. At a low intensity of the beam of radiation received by the radiation detector 6 in FIG. 1 the pulse shaping means 16 can suitably be connected to the output of the summation means 12 via a phase-locked oscillator of a known construction for providing a phase shift of zero degrees between the outgoing and the incoming signal. | The invention relates to an optical fire-detector in which a radiation-emitting means is arranged to emit a beam of radiation and which has modulator means for the modulation of the beam of radiation in a phase-inverted relationship within a first and a second wavelength band, and a radiation-detecting means is arranged to receive the beam of radiation after it has passed through an intermediate air medium and includes first means for an individual measurement of intensity in the two wavelength bands and second means for the detection of such variations in the measured intensities which are representative for a fire. | 6 |
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 equipment for separating molten sulfur from associated gases in industrial operations producing molten sulfur, such as oil refineries. More specifically, this invention relates to a seal for a sulfur trap.
2. Description of the Related Art
Gaseous compounds containing sulfur, such as hydrogen sulfide, mercaptans, carbonyl sulfide, carbon disulfide, exist in natural gas. Such gaseous compounds are produced as by-products in petroleum refining operations.
In industrial applications, gas streams containing sulfur compounds are processed to remove sulfur (primarily in the form of hydrogen sulfide). The gas streams are then further processed to form liquid sulfur in sulfur recovery units.
Conventional sulfur recovery units include a seal leg or trapping device to separate molten sulfur from the gas stream. The molten sulfur is condensed from the remaining gas stream.
The discharge into the atmosphere of residual tail gases associated with such molten sulfur, such as sulfur dioxide and hydrogen sulfide, is environmentally unacceptable. It is therefore necessary to separate the elemental sulfur from the tail gases associated therewith.
Sulfur traps associated with sulfur recovery units, as historically designed, include two concentrically arranged vertical pipes. The vertical pipes may extend approximately twenty feet to twenty-five feet into the ground. The outer pipe is capped at its lower end. The inner pipe lower end is displaced above the capped lower end of the outer pipe allowing molten sulfur to flow from the inner pipe to the annular space between the pipes. Molten sulfur is received into the inner pipe, flows downwardly from the inner pipe and upwardly in the annular space between the inner pipe and the outer pipe to a discharge pipe connected to the outer pipe. The discharge pipe transmits the sulfur into a sulfur storage tank where the sulfur may be maintained until pumped out for shipping or other disposition. A jacket is provided outside the outer pipe, with steam circulated between the jacket and the outer pipe to maintain the temperature of the sulfur trap above 250 degrees Fahrenheit and accordingly to maintain the sulfur in a liquid phase. The annular arrangement of the inner pipe and outer pipe provides a liquid trap preventing tail gases from being transferred in the storage tank.
Kuvasnikoff et al U.S. Pat. No. 4,185,140, Sims U.S. Pat. No. 4,255,408 and Singleton et al. U.S. Pat. No. 4,085,199 disclose processes for removing sulfur and sulfur compounds from sulfur bearing gases.
Stothers U.S. Pat. No. 4,504,459 discloses process and apparatus for extraction of elemental sulfur from sulfur compound gases.
Mori et al. U.S. Pat. No. 4,341,753 and Hellmer et al. U.S. Pat. No. 4,117,100 disclose processes and apparatus for converting sulfur dioxide and gas to sulfur.
Scott et al. U.S. Pat. No. 4,035,158 discloses a process and apparatus for burning hydrogen sulfide and other combustible fluids to recover sulfur.
Conventional in-ground sulfur traps require ground excavation and buried lines to install the concentric piping, the steam jacket and steam lines. In operation, the inner pipe or the annulus may become blocked or partially blocked from time to time by materials such as contaminated sulfur, carbon, catalyst dust, etc. To remove the blockage it is often necessary that the trap be partially disassembled and the inner pipe or annulus rodded out to restore circulation.
Operating pressures upstream of the conventional in-ground sulfur traps must be limited due to the nature of the liquid trap. Other disadvantages of conventional sulfur seal systems are that they extend 20′ or more into the earth, and that they are not easily cleaned.
U.S. Pat. No. 5,498,270 by this inventor discloses a sulfur trap that includes a sphere that engages an upwardly extending cylinder in a first position and that floats in the molten sulfur contained in the upper chamber in a second position.
The sulfur trap disclosed in U.S. Pat. 5,498,270 provided improved sealing over the prior art sulfur separation systems while allowing the process to operate at relatively high pressures upstream of the seal. Additionally, it did not require deep excavation and was relatively easy to clean.
The present invention comprises an improvement to the art by providing a self-cleaning mechanism on the trap enhancing the sealing interface.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide a system that effectively separates elemental molten sulfur from associated tail gases and that has an improved sulfur sealing system.
It is also an object of the present invention to provide a self-cleaning mechanism to reduce solid sulfur build-up in the sulfur trap.
The sulfur trap of the present invention comprises generally a vertically-elongated upper chamber for receiving molten sulfur together with sulfur containing gases, a lower chamber disposed below the upper chamber, a wall segregating the lower chamber and the upper chamber, an orifice provided in the wall for fluid transfer from the upper to the lower chamber, an upwardly extending hollow cylinder adjacent the orifice wall, a spherical device in said upper chamber, a sealing device attached to said spherical device, said device engaging the upwardly extending cylinder in a first sealing position and said device floating in the molten sulfur contained in the upper chamber in a second sulfur-flowing position. The sealing device includes a counterweight extending from the lower outer surface. A beveled surface on the counterweight engages a beveled surface around the top of the upwardly extending cylinder. When the sealing device is in a first position, the beveled surface of the counterweight nests with the beveled surface of the upwardly extending cylinder and a portion of the counterweight is contained within the upwardly extending cylinder. A cleaning rod extends below the counterweight, further into the upwardly extending cylinder. Upon introduction of the molten sulfur into the upper chamber in sufficient quantities, the hydrostatic pressure of the molten sulfur displaces the spherical device upwardly to allow molten sulfur to flow through the orifice into the lower chamber. When the molten sulfur displaces the sealing device into the second position, the counterweight maintains the device orientation and the cleaning rod keeps the device aligned with the upwardly extending cylinder. The cleaning rod and counterweight reduce solid sulfur accumulations from the side of the cylinder and interface surface.
A discharge is fluidly connected to the lower chamber. An external shell is provided around the upper and lower chambers for circulating steam in the annular space between the shell and the upper and lower chambers to maintain the sulfur in a liquid phase.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 FIG. 1 depicts a cross-sectional view of the sulfur trap of the present invention.
FIG. 2 depicts a partial cross-sectional view of the sealing device engaging the cylindrical member in a first closed position.
FIG. 3 depicts a cross-sectional view of the dividing wall segregating the upper and lower chambers.
DESCRIPTION OF THE INVENTION
Referring first to FIG. 1 , the sulfur trap 10 of the present invention is depicted in a cross-sectional drawing. The sulfur trap 10 includes an elongated, vertically oriented, cylindrical wall 12 having a segregating plate 14 horizontally disposed therein, segregating plate 14 defining an upper chamber 16 and a lower chamber 18 within cylindrical wall 12 . An orifice 20 is provided centrally of plate 14 . An upwardly extending, cylindrical member 22 is attached to the plate 14 with the hollow center of cylindrical member 22 aligned with the orifice 20 provided in segregating plate 14 . Cylindrical member 22 is provided with edges beveled outwardly along an upper edge 23 , shown in FIG. 3 . Upwardly extending rods 24 are fixedly attached to plate 14 between the cylindrical member 22 and cylindrical wall 12 .
A sealing device 120 is disposed on the upper end of cylindrical member 22 . In the preferred embodiment, sealing device 120 includes a sphere 26 , a counterweight 110 and a cleaning rod 114 . Counterweight 110 is affixed to the underside of sphere 26 . Counterweight 110 has a beveled surface 112 , depicted in FIG. 2 . Cleaning rod 114 extends downwardly from counterweight 110 through orifice 20 . As depicted in FIG. 2 , beveled surface 112 engages upper edge 23 of cylindrical member 22 when sealing device 120 is not floating in the molten sulfur.
Counterweight 110 is provided with an arcuate lower surface 118 . The arcuate lower surface 118 facilitates centering of counterweight 110 in cylindrical member 22 .
When sealing device 120 is pushed upwards from cylindrical member 22 , counterweight 110 serves to maintain sphere 26 in an orientation such that counterweight 110 is always below sphere 26 . The flow of molten sulfur can cause sphere 26 to float slightly from side to side. As sphere 26 shifts, cleaning rod 114 scrapes the inside of cylindrical member 22 , thereby removing sulfur solids (not shown) that may have accumulated. Cleaning rod 114 also keeps sphere 26 aligned with cylindrical member 22 so that when the flow of molten sulfur stops, sphere 26 will come to rest with beveled surface 112 interfacing with beveled edge 23 on cylindrical member 22 .
In the preferred embodiment, counterweight 110 extends into cylindrical member 22 when sealing device 120 is seated against cylindrical member 22 . As the flow of molten sulfur pushes sealing device 120 upwards, the portion of counterweight 110 within cylindrical member 22 disengages sulfur solids that may have accumulated. Beveled surface 112 also scrapes upper surface 23 , removing sulfur solids (not shown) that interfere with the seal between sealing device 120 and cylindrical member 22 .
Referring to FIG. 1 , an inlet orifice 28 is provided near the upper end of chamber 16 in cylindrical wall 12 . Inlet orifice 28 is connected to inlet pipe 32 . Inlet pipe 32 is connected to an inlet pipe flange 34 . Inlet pipe flange 34 is connected to a condenser (not shown) or other source of molten elemental sulfur and associated sulfur-containing gases. Inlet pipe 32 provides fluid communication between upper chamber 16 and the condenser.
Still referring to FIG. 1 , a second upper chamber orifice 30 is provided near the upper end of upper chamber 16 in cylindrical wall 12 . Said second orifice 30 is connected to connecting pipe 36 . Connecting pipe 36 is connected to connecting flange 38 . As depicted in FIG. 1 , connecting flange 38 is connected to a blind flange 40 .
As depicted in the preferred embodiment, molten sulfur inlet to the sulfur trap 10 may be introduced into the sulfur trap 10 through inlet orifice 28 and inlet pipe 32 . However, orifice 30 and connecting pipe 36 are provided for alternate inlet means of molten sulfur or for cleaning the sulfur inlet line connected to inlet pipe 32 of any solids deposited therein by using a straight rod.
A screen assembly 42 is disposed horizontally in upper chamber 16 below orifices 28 and 30 . The screen is above and remote from segregating plate 14 .
Still referring to FIG. 1 , a rounded cap 44 is provided at the upper end of cylindrical wall 12 . Cap 44 is hingedly attached to cylindrical wall 12 .
A discharge orifice 52 is provided in cylindrical wall 12 near its lower end at lower chamber 18 . A discharge pipe 54 is connected to discharge orifice 52 . Discharge pipe flange 82 is connected to discharge pipe 54 at its end distal from discharge orifice 52 .
Shell members 66 , 76 , 78 and 80 are provided around the cylindrical wall 12 , inlet pipe 32 , connecting pipe 36 and connecting pipe 54 .
Referring now to FIG. 3 , details of construction of the segregating plate 14 are depicted. Segregating plate 14 comprises a generally circular plate connected to the interior surface of cylindrical wall 12 throughout the exterior circumference of the plate 14 . Orifice 20 is centrally located in connecting plate 14 . Cylindrical member 22 extends upwardly from plate 14 into upper chamber 16 .
Cylindrical member 22 is provided with upper edges beveled outwardly. The beveled edges create an upper edge 23 of outer wall 22 . Absent an obstruction such as sealing device 120 , the orifice 20 and the interior of hollow cylindrical member 22 provide fluid communication between upper chamber 16 and lower chamber 18 .
Still referring to FIG. 3 , a plurality of rods 24 , are connected to plate 14 , said rods extending upwardly into upper chamber 16 . Four rods 24 are provided in the preferred embodiment shown. Rods 24 are provided with rounded upper ends. Rods 24 are inclined outwardly at the upper ends. Rods 24 serve to center the sphere 26 over cylindrical member 22 and are sized and spaced accordingly.
OPERATION
Referring to FIG. 1 , the operation of the present invention is depicted. Molten sulfur is received into upper chamber 16 through inlet pipe 32 , the molten sulfur containing tail gases including gaseous compounds containing sulfur, such as hydrogen sulfide, mercaptans, carbonyl sulfide, and carbon disulfide. Such molten sulfur is induced by gravity to flow through the screen assembly 42 , where large particles, including coagulated clumps of sulfur and sulfur compounds, are segregated from the molten sulfur. As a volume of sulfur accumulates in the upper chamber 16 , the sealing device 120 is displaced upwardly from its resting place at the upper edge 23 of cylindrical member 22 . The sealing device 120 is constructed with such an average density to float in molten sulfur. Such displacement of sealing device 120 allows molten sulfur to flow through the orifice 20 into lower chamber 18 and thence through discharge pipe 54 to a storage tank or other receptacle.
The flow of molten sulfur into the lower chamber 18 continues during the period that sphere 26 is displaced from upper edge 23 . A liquid seal is maintained during such flow by the liquid sulfur, preventing process gas from escaping with liquid sulfur to the lower chamber. As sealing device 120 is displaced from cylindrical member 22 , counterweight 110 maintains sphere 26 in an orientation relative to cylindrical member 22 with counterweight 110 below sphere 26 . Variations in the flow of molten sulfur cause sphere 26 to rotate and move slightly from side to side. As sphere 26 rotates and moves, cleaning rod 114 scrapes solid sulfur build up from the inside surface of cylindrical member 22 , thereby keeping it free of solid sulfur accumulation that can inhibit the flow of molten sulfur to lower chamber 18 . Counterweight 110 also scrapes the top inner portion of cylindrical member 22 and upper edge 23 , reducing solid sulfur build up that compromises the integrity of the seal between counterweight 110 and cylindrical member 22 when the flow of molten sulfur decreases.
Upon reduction of volume of molten sulfur in upper chamber 16 , sphere 26 with counterweight 110 drops to its original position at upper edge 23 of cylindrical member 22 . Arcuate lower surface 118 facilitates centering of counterweight 110 in cylindrical member 22 . Further flow of molten sulfur through orifice 20 is thereby terminated. The centering of sphere 26 on upper edge 23 is facilitated by rods 24 , said rods 24 being so located and sized as to direct sphere 26 to the center of chamber 16 . Further, cleaning rod 114 facilitates the centering of counterweight 110 over cylindrical member 22 . Beveled surface 112 interfaces with upper edge 23 to provide an effective seal against such flow of molten sulfur.
Steam is continually circulated through the annular spaces between shell members 66 , 76 , 78 , and 80 and cylindrical wall 12 , inlet pipe 32 , connecting pipe 36 and discharge pipe 54 to maintain the temperature within sulfur trap 10 above 250 degrees Fahrenheit. The sulfur contained within sulfur trap 10 is thereby maintained in a liquid phase.
As required for cleaning and to remove coagulated sulfur material, cap 44 may be rotated to an open position. The screen assembly 42 may then be removed from the upper chamber 16 .
The foregoing description of the invention illustrates a preferred embodiment thereof. Various changes may be made in the details of the illustrated construction within the scope of the appended claims without departing from the true spirit of the invention. The present invention should only be limited by the claims and their equivalents. | A sealing device for a sulfur trap includes a float, a counterweight, and a cleaning rod. The density of the sealing device allows flotation of the device in molten sulfur. The counterweight includes a surface to mate with an upwardly extending hollow cylinder in the sulfur trap through which molten sulfur may flow. The sealing device engages the upwardly extending cylinder in a first position and floats in the molten sulfur contained in an upper chamber of the sulfur trap in a second position. The cleaning rod and counterweight contact the sides of the upwardly extending cylinder to prevent buildup of solid sulfur. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation of pending patent application Ser. No. 15/284,688, filed Oct. 4, 2016, which is a continuation of U.S. Pat. No. 9,491,915, filed Jun. 10, 2011, which is a continuation-in-part of U.S. Pat. No. 8,327,582, filed Aug. 2, 2010, entitled “Vertical Hydroponic Plant Production Apparatus” which claims benefit of priority of provisional patent application Ser. No. 61/273,317, filed on Aug. 3, 2009, entitled “Vertical Hydroponic Plant Production Apparatus”, the contents of which are all incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to a vertical hydroponic plant production apparatus and, more particularly, the invention relates to a vertical hydroponic plant production apparatus utilizing fibrous, non-woven, air-laden media allowing for vertical hydroponic greenhouse crop production in a fraction of the space necessary for traditional plant production techniques and allowing utilization of vertical surfaces for plant production.
[0004] 2. Description of the Prior Art
[0005] Traditional hydroponics has focused primarily on horizontal production techniques and has been subject to major space constraints. Vertical hydroponic applications have either been impractical, expensive to operate, or inefficient. Often these applications utilize some type of growth medium that is heavy when saturated, causing clogging when filled with plant roots, and/or requiring a great deal of maintenance. In addition, conventional technology makes it difficult to allow in-store display of live, growing vegetables and is not conducive to “you-pick” vegetable and herb sales to customers. Little technology exists that allows vertical plant displays that are highly scalable.
SUMMARY
[0006] The present invention is a growing medium for a plant production apparatus utilized in greenhouse crop production. The growing medium comprises a fibrous, non-woven matrix media material wherein the media material is constructed from a plastic material.
[0007] In addition, the present invention includes a method for growing plants in a plant production apparatus utilized in greenhouse crop production. The method comprises providing a fibrous, non-woven matrix media material and constructing the media material from a plastic material.
[0008] The present invention further includes a growing medium for a plant production apparatus utilized in greenhouse crop production. The growing medium comprises a fibrous, non-woven matrix media material and a silicone binder coating the media material for slowing decomposition and reducing UV damage. The media material is constructed from a plastic material and the media material has sufficient shear strength to be cut into strips and used in hydroponic environments and be free from tearing when pulled.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a front perspective view illustrating a grow tube of a vertical hydroponic plant production apparatus, constructed in accordance with the present invention;
[0010] FIG. 2 is a rear perspective view illustrating the grow tube of the vertical hydroponic plant production apparatus of FIG. 1 , constructed in accordance with the present invention;
[0011] FIG. 3 is a front perspective view illustrating another embodiment of the grow tube of the vertical hydroponic plant production apparatus, constructed in accordance with the present invention;
[0012] FIG. 4 is a rear perspective view illustrating the grow tube of the vertical hydroponic plant production apparatus of FIG. 3 , constructed in accordance with the present invention;
[0013] FIG. 5 is a front perspective view illustrating a media column of the vertical hydroponic plant production apparatus, constructed in accordance with the present invention;
[0014] FIG. 6 is a rear perspective view illustrating the media column of the vertical hydroponic plant production apparatus of FIG. 5 , constructed in accordance with the present invention;
[0015] FIG. 7 is a perspective view illustrating a Z bracket of the vertical hydroponic plant production apparatus, constructed in accordance with the present invention; and
[0016] FIG. 8 is a perspective view illustrating a pulling hook of the vertical hydroponic plant production apparatus, constructed in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] As illustrated in FIGS. 1-8 , the present invention is a vertical hydroponic plant production apparatus, indicated generally at 10 , allowing vertical hydroponic greenhouse crop production in a fraction of the space necessary for traditional plant production techniques and allows utilization of vertical surfaces for plant production.
[0018] The vertical hydroponic plant production apparatus 10 of the present invention includes a grow tube 12 useable in a horizontal position, vertical position, or any position between the horizontal position and the vertical position. The grow tube 12 is highly portable, being light, making it easy to move the grow tube 12 from area to area for transplant, grow out, and harvest. The grow tube 12 further allows inclined, multi-angled crop production and multi-storied conveyor style crop production. The grow tube 12 of the vertical hydroponic plant production apparatus 10 of the present invention also functions as aquacultural biofiltration/nutrient stripping devices for plant-based, high-efficiency waste nutrient removal and as sites nitrification processes, having massive surface area/volume thereby reducing the costs of single pass aquaculture and improving the efficiency of recirculating aquaculture.
[0019] The grow tube or tower 12 of the vertical hydroponic plant production apparatus 10 of the present invention also functions as in-store or at market display devices allowing the display of fresh, live produce for you-pick vegetable sales at market places and allowing the sale of produce that is more fresh than traditionally harvested vegetable products. Designed for easy affixation to the walls and/or roofs of buildings, the grow tube 12 reduces heating and cooling costs through shading and plant evapotranspiration and performs a decorative function. The grow tube 12 applied in such a manner can also reduce rooftop and hard surface water runoff depending on application and plumbing system.
[0020] Basically, the vertical hydroponic plant production apparatus 10 of the present invention allows for decorative landscape designs as well as vertical plant production displays indoors for a variety of purposes. The grow tubes or towers 12 can house aromatic and decorative species of herbs that may be used for aromatherapy type interactive hallways, lobby displays, kitchen, and cafeteria displays as well as common industrial plant displays in offices and workspaces.
[0021] The grow tube 12 of the vertical hydroponic plant production apparatus 10 of the present invention has a first end 14 and a second end 16 and is preferably a square, triangular, or angular tubing containing a non-woven matrix media 18 composed of any number of plastic materials, suspended vertically from the ceiling, supported by a framework, and/or standing upright on the floor using a support pole or frame. The media 18 is preferably a fibrous, non-woven, air laid media made of polyethylene plastic, although it can also be made of any type of plastic. The media 18 can be coated with a silicone binder to slow decomposition and reduce UV damage and is characterized by its high surface area to volume ratio, high shear strength, and durable yet flexible structure. The media 18 functions as a mechanical filter media as well as substrate for biological filtration. Because of the high shear strength, the media 18 , can be cut into strips and used in hydroponic environments where long strips are pulled and stressed without tearing. Crop seeds can be seeded directly into the media 18 , or can be incorporated into the media 18 as seedlings a variety of ways. Seedlings can be inserted into holes cut in the media 18 , between two or more pieces of media 18 , or can be germinated beneath the media 18 , with shoots protruding through the media 18 . The media 18 can be used in raft hydroponics, as a media substrate for media based hydroponics or as a plant anchor in NFT hydroponics. The media 18 is an excellent substrate for root development and protection, biological interactions, and soil and substrate stabilization. Once used for plant production, the media 18 contains a great deal of organic matter and holds water quite well. At this point the material introduces a number of water and nutrient holding and moderation capabilities. The media 18 is also excellent for supporting redworm ( Eisenia fetida ) colonies as well as diverse colonies of soil bacteria and fungi. The media 18 can be used as a substrate for algae production as well.
[0022] Preferably, the grow tube 12 the vertical hydroponic plant production apparatus 10 of the present invention is constructed of a PVC plastic material with side walls having a width of approximately four (4″) inches to six (6″) inches although constructing the grow tube from a different material with different widths is within the scope of the present invention. The grow tube 12 has a slot 20 formed lengthwise through the grow tube 12 . The slot 20 can be formed along the entire face of the grow tube 12 from the first end 14 to the second end 16 or the slot 20 can be formed to a point approximately four (4″) inches to approximately six (6″) inches from the first end 14 of the grow tube 12 . In the case of the slot 20 formed along the entire face of the grow tube 12 , the slot 20 can have angled portions 22 at the first end 14 of the grow tube 12 allowing for easy insertion and removal of the media, as will be described further below. Preferably, the slot 20 has a width of approximately one-half (½″) inch to approximately one and one-half (1½″) inches although constructing the slot 20 with different widths is within the scope of the present invention.
[0023] As mentioned briefly above, the vertical hydroponic plant production apparatus 10 of the present invention has a media material 18 preferably constructed from a polyester matrix material approximately two (2″) inches thick, cut to the internal width/diameter of the grow tube, and folded in the middle so that both halves together roughly equal the inside dimensions of the grow tube or tower housing 12 . The media material 18 can also be composed of two halves of approximately two (2″) inch thick media or one piece of four (4″) inch thick media split down the middle to within approximately four (4″) inches to approximately six (6″) inches of the top of the media material where a bolt spans its width. In the bolt embodiment of the present invention, this bolt not only spans the width of the media insert 18 , joining the two halves, and/or lending structural integrity to the media insert, but also anchors a handle or receiver to the media 18 , allowing either the handle to be grasped for the purposes of inserting and removing the media 18 insert from the grow tube 12 , or allowing a forked or hooked handle to be inserted into the receiver for the same purpose.
[0024] In the embodiment of the vertical hydroponic plant production apparatus 10 of the present invention where the media material 18 is folded in half, a pulling hook 24 with a flat hook 26 attached to a handle 28 allows the media inserts 18 to be pulled into and out of the grow tube 12 , with the pulling hook handle 28 extending from the slot 20 in the grow tube 12 . The hook 24 preferably consists of a piece of round bar metal bent to form a broad, flat, “L” shaped hook, roughly the width of the folded media 18 with a handle 28 affixed to the end. The hook 26 can also be attached to a pneumatic or hydraulic device that allows automated “pulling” of the media inserts 18 .
[0025] For planting, seedlings are placed between the two halves of media 18 of the vertical hydroponic plant production apparatus 10 of the present invention, with the upper portions out, and are “zipped” into the grow tubes 12 with the upper portions of the plant protruding through the gap in the tower housing 12 . The top of the grow tube 12 can be capped with a removable cap having holes of variable sizes drilled in the center, or may not be capped at all. If capped, a mister or irrigation tubing is inserted through the hole in the cap hole. The bottom of the grow tube 12 is either submerged in nutrient solution, rests in a drain or trough for recirculating nutrient solution, or fits into a lower pipe. A pump moves nutrient solution from a nutrient solution reservoir to the mister or irrigation pipe at the top of the grow tube 12 , where the nutrient solution is emitted and allowed to drip down through the media 18 and plant roots. Some of the nutrient solution trickles down the walls of the pipe 12 and is captured by roots in contact with the pipe wall. Excess nutrient solution drains to the bottom of the pipe 12 where it is drained back to the nutrient solution reservoir. High humidity is maintained within the grow tube due to the constant trickling/misting of nutrient solution. The height of the plant grow tube 12 is variable dependent on greenhouse height, and the spacing for plants is variable dependent on plant type and desired spacing. It is possible to stack grow tubes 12 on top of each other to vary height, by fitting the bottoms of the grow tubes 12 with coupling caps, to utilize conveyor production techniques.
[0026] The grow tubes 12 of the vertical hydroponic plant production apparatus 10 of the present invention can be fixed in place using hangers, rope, or strap and metal hooks that loop over a support beam or bracket and secure to the grow tube 12 or tower through holes 30 drilled at the first end of the grow tube 12 . The holes 30 can be of variable size and placement depending on application, although in the most common embodiment, there are four holes 30 , one pair centered on either side of the housing upper, and one pair forward (towards the front of the grow tube 12 ) of the centered pair allowing slight inclination of the hanging tower 12 if inclined growing is desired. The grow tubes 12 can also be fixed in place using a series of holes or a gap cut in the grow tube 12 allowing the grow tube to be fixed to a pole having a bracket or pressure or spring action hanging system attached to it. The grow tube 12 can also be inclined on said pole or hanging system for the purpose of inclined production.
[0027] The grow tube 12 of the vertical hydroponic plant production apparatus 10 of the present invention can also be secured to a support pole utilizing a system of metal brackets whereas one bracket type is female and is designated as an “H” bracket 32 and the other bracket type is male and is designated as a “Z” bracket 34 . The female “H” bracket 32 has a receiving portion and an anchoring portion to bolt to the back or side of the tower 12 . The male “Z” bracket 34 consists of a vertical, upward facing tongue portion that fits into the receiving portion of the female bracket 32 , and has a hole 36 through the middle, angled portion of the bracket 34 which fits over a support pole. The rear, downward facing vertical portion of the bracket 34 has a hole 38 drilled midway across the bottom of the bracket 34 and is threaded to receive a bolt. As weight is applied to the tongue portion of the bracket 34 through the placement of a bracketed tower, downward torque is applied across the “Z” bracket 34 causing a clutch action to affix the bracket tightly to the support pole. The torque attachment of this “Z” bracket 34 can be enhanced by tightening the bolt threaded into the rear of the bracket 34 against the support pole, applying even more pressure for bracket attachment.
[0028] The media insert 18 of the vertical hydroponic plant production apparatus 10 of the present invention can also be altered in several ways to serve a diverse range of functions. The media 18 can be cut at a taper from the unfastened or unfolded end to the fastened or folded end, reserving a tapered space at the rear of the insert to allow compost, alternate plant media, fertilizing substance or some type of soil amendment or additive to be held in the space between the tapered media insert and the rear and sidewalls of the tower housing 12 . This alteration allows compost based hydroponic plant production using regular irrigation water, with plant nutrients supplied by the compost or other additive. Tops, sides, and corners of the media insert 18 can also be cut, rounded, or cut at an angle to reduce biosolids accumulation, algal growth, or to enhance water distribution through the media 18 , depending on application. Multiple inserts 18 can also be used in towers 12 allowing multiple age groups of plants to incorporated into each grow tube 12 . Worms are also commonly integrated into the grow tubes 12 and the media is designed to have the correct mesh size to accommodate their movement through the media 18 , although media 18 with a smaller or larger mesh size may be used depending on application.
[0029] The vertical hydroponic plant production apparatus 10 of the present invention is comparatively lightweight, inexpensive to manufacture (being based on common PVC extrusion techniques) and existing polyethylene matrix material production, will not clog with nutrient solution, and requires much less labor to operate. The present invention can also be converted to more traditional horizontal production techniques if desired, eliminating the risk inherent in changing production techniques for commercial producers.
[0030] In addition, traditional nitrogen and phosphorus removal techniques in aquaculture are very poor compared to removal using plant uptake for phytoremediation. Plants are able to remove N and P to levels an order of magnitude lower than any mechanical/chemical/microbial technique currently in use. The present invention phytoremediates water allowing for prolonged water use/recirculation and water conservation.
[0031] The vertical hydroponic plant production apparatus 10 of the present invention is an improvement on traditional harvesting and sales models where production systems are physically removed from the sales systems and shipping and handling results in a large percentage of producer losses, both financially as wasted or expired produce. By selling live plants, there is no spoilage and shipping and handling is done partially by producers moving towers to market places, but primarily by consumers who are interested in fresh produce and the experience of picking and harvesting vegetables, herbs and greens for their own use. The grow tubes are easily transported and easy to stack, lift, and slide onto shelves. They essentially operate as a packaging system as well as a plant production system. Further, by utilizing individual towers, landscape designers and home users can scale their display or production system exactly to their specifications.
[0032] The vertical hydroponic plant production apparatus 10 of the present invention reduces necessary growing space tremendously. Typical reductions in growing space utilizing a vertical aeroponic technique have varied between 60% and 85% compared to conventional growth methods. Greenhouse growing space is very expensive, so the ability to increase crop size without increasing greenhouse space could prove very profitable. The present invention is also very affordable to manufacture, building on existing PVC pipe production infrastructure. Implementation of the present invention will also be simple, building on current hydroponic production technology.
[0033] The increased water recirculation time achieved with the vertical hydroponic plant production apparatus 10 of the present invention can eliminate one of the high costs and reduce the negative environmental effects of aquaculture, resulting in increased profits and a better industry image for aquacultural producers. Using the present invention can also allow aquacultural producers to diversify their product base and/or grow supplementary feed products (depending on the dietary needs of the fish).
[0034] The vertical hydroponic plant production apparatus 10 of the present invention has the potential to open up an entirely new system of production, transportation, shipping, handling, and display to vegetable producers, retailers, and consumers. This can result in fresher produce, a more pleasant customer shopping experience, reduced waste, reduced handling and packaging costs, fewer food miles, less plastic and packaging material consumption, and longer shelf life of purchased produce.
[0035] The vertical hydroponic plant production apparatus 10 of the present invention can be used by industrial institutions for phytoremediation of waste waters, using the towers as trickling, plant integrated filters for the removal of waste materials, and the remediation of waste waters for discharge.
[0036] The foregoing exemplary descriptions and the illustrative preferred embodiments of the present invention have been explained in the drawings and described in detail, with varying modifications and alternative embodiments being taught. While the invention has been so shown, described and illustrated, it should be understood by those skilled in the art that equivalent changes in form and detail may be made therein without departing from the true spirit and scope of the invention, and that the scope of the present invention is to be limited only to the claims except as precluded by the prior art. Moreover, the invention as disclosed herein may be suitably practiced in the absence of the specific elements which are disclosed herein. | A growing medium for a plant production apparatus utilized in greenhouse crop production is provided. The growing medium comprises a fibrous, non-woven matrix media material wherein the media material is constructed from a plastic material. | 0 |
BACKGROUND OF THE INVENTION
The present disclosure generally relates to methods and apparatus for determining the heart rate of a subject. More specifically, the present disclosure particularly relates to a method and apparatus for determining the beat-to-beat heart rate of a fetus.
Fetal monitoring (i.e., monitoring of the fetal condition during gestation and at birth) usually comprises monitoring uterine activity and the fetal beat-to-beat heart rate. The fetal heart rate, which provides an indication of whether the fetus is sufficiently supplied with oxygen, is preferably calculated from beat to beat.
To obtain a signal indicative of the fetal heart rate prior to rupture of the membranes, a noninvasive monitoring technique must be used. The most widely adopted measurement technique involves measuring the Doppler shift of an ultrasound signal reflected by the moving fetal heart.
In accordance with a known ultrasonic detection technique, an ultrasound transducer is placed externally on the pregnant woman's abdomen and oriented such that the transmitted ultrasound waves impinge upon the fetal heart. The reflected ultrasound waves are received either by the same or by a different ultrasound transducer. The Doppler shift of the reflected ultrasound wave is directly related to the speed of the moving parts of the heart, e.g., the heart valves and the heart walls.
Although the Doppler ultrasound is widely accepted and generally accepted method of monitoring fetal heart rate, ultrasound fetal heart rate monitoring has several drawbacks. One of these drawbacks is that the ultrasound fetal monitor transducer may not be able to monitor the fetal heart rate of a fetus in the case of an obese mother since the distance from the mother's skin surface to the fetal heart may be greater than the monitoring depth of the fetal heart rate monitor. Alternatively, ultrasonic fetal heart rate monitors that use a higher dose of ultrasound energy to increase the depth of sensing expose normal or underweight patients to a higher degree of ultrasonic energy than may be otherwise required.
BRIEF DESCRIPTION OF THE INVENTION
The present disclosure relates to a method and apparatus for determining the beat-to-beat heart rate of a fetus. In a disclosed embodiment, the continuous, non-invasive fetal heart rate measurement is produced using one or more ultrasonic transducers that are adhered or attached to the abdomen of a pregnant patient. Each ultrasound transducer generates an ultrasound beam that is reflected by the fetal heart and received by one or more of the ultrasound transducers. Based upon the received signal, the fetal heart rate monitor generates the heart rate of the fetus.
The fetal heart rate monitor of the present disclosure includes an excitation voltage generator that generates a standard excitation voltage. The excitation voltage from the excitation voltage generator is received by an excitation voltage adjustment device. The excitation voltage adjustment device, in turn, is connected to a controller that is operable to control the operation of the excitation voltage adjustment device.
During operation of the fetal heart rate monitor, an excitation voltage is initially applied to the ultrasound transducer. The signal strength of the ultrasound beam from each of the transducers is directly related to the excitation voltage.
If the strength of the ultrasound beam is insufficient to detect the fetal heart rate, a user can operate a user input device to indicate that the strength of the ultrasound beam needs to be increased. When the controller of the fetal heart rate monitor receives such a signal from the input device, the controller provides a signal to the excitation voltage device to increase the excitation voltage.
When the excitation voltage is increased by the excitation voltage adjustment device, the strength of the ultrasound beam from the ultrasound transducers increases, thereby increasing the depth of viewing for the fetal heart rate monitor. The controller operates a power level display to graphically illustrate to the operator the current signal strength from the ultrasound transducers relative to a maximum level.
The user can continue to increase the signal strength of the ultrasound beam until the fetal heart rate is detected. Once the fetal heart rate is detected, the heart rate is displayed and the user can allow the signal strength to remain at the current level. In this manner, the signal strength of the ultrasound beam is optimized for each individual patient such that each patient receives only the required ultrasound level needed to detect the fetal heart rate.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate the best mode presently contemplated of carrying out the disclosure. In the Figures:
FIG. 1 depicts a pregnant patient utilizing fetal heart rate monitor;
FIG. 2 is a schematic illustration of the ultrasound power control system of the present disclosure;
FIG. 3 is one embodiment of the excitation voltage adjustment device;
FIG. 4 is a second embodiment of the excitation voltage adjustment device; and
FIG. 5 is a graphic display of the power level of the ultrasound beam.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a fetal heart rate monitor 10 that can be used to monitor the heart rate of the fetus of a pregnant patient 12 . Although the fetal heart rate monitor 10 is shown in FIG. 1 in one exemplary form, it should be understood that the fetal heart rate monitor 10 could take many other forms while operating within the scope of the present disclosure.
In the embodiment of FIG. 1 , the fetal heart rate monitor 10 includes an ultrasound probe 14 that is secured to the patient's abdomen 16 by a strap 18 . The ultrasound probe 14 is shown in the embodiment of FIG. 1 as being coupled to the fetal heart rate monitor 10 by cable 20 . However, it is contemplated that the fetal heart rate monitor 10 could communicate with the ultrasound probe 14 using a wireless communication technique.
The fetal heart rate monitor 10 is shown in FIG. 1 as including a display screen 22 that typically displays the monitored heart rate of the fetus. The display screen 22 can be configured to display other monitored signals obtained from the patient 12 .
During operation, when the fetal heart rate monitor 10 is powered on, one or more ultrasound transducers contained within the ultrasound probe 14 each generate an ultrasound beam directed into the patient 12 through the skin of the abdomen. The fetal heart rate monitor 10 monitors the ultrasound signal returned to either the same or a different ultrasound transducer contained within the ultrasound probe 14 to detect the beating of the fetal heart. Based upon data acquired from the ultrasound probe 14 , the fetal heart rate monitor 10 calculates the fetal heart rate and displays the calculated fetal heart rate on the display 22 in a known manner.
Referring now to FIG. 2 , the detailed operation of the fetal heart rate monitor 10 will now be described. As illustrated in FIG. 2 , the ultrasound probe 14 is positioned on the exterior surface of the patient's abdomen 16 . In the embodiment shown in FIG. 2 , the ultrasound probe 14 includes multiple ultrasound transducers 24 . Each transducer 24 is operable to both generate an ultrasound beam 26 and receive reflected ultrasound energy from the fetal heart. In one embodiment of the disclosure, each of the ultrasound transducers 24 is a piezoelectric crystal that vibrates to create the ultrasound beam 26 emanating from the ultrasound transducer. The vibration of the piezoelectric crystal is created by an excitation voltage applied to the piezoelectric crystal through a voltage supply line 28 .
Although in the embodiment shown in FIG. 2 each of the ultrasound transducers 24 is able to both transmit the ultrasound beam and receive the reflected ultrasound energy, the ultrasound probe 14 could utilize separate transducers for transmitting and receiving the ultrasound energy.
During operation of the fetal heart rate monitor 10 , the ultrasound transducers 24 generate the ultrasound beam 26 that penetrates the patient's abdomen 16 and travels into the pregnant patient until the ultrasound signal is reflected by the beating fetal heart 30 . As illustrated in FIG. 2 , the distance A from the outer surface of the abdomen 16 to the fetal heart 30 must fall within the range of detection for the ultrasound transducers 24 . The range of detection of the ultrasound transducers 24 is directly related to the signal strength of the ultrasound beam 26 . In turn, the strength of the ultrasound beam 26 is directly related to the voltage level of the excitation voltage applied to the ultrasound transducers 24 along the voltage supply line 28 . If the position of the fetal heart 30 is outside of the detection range of the ultrasound transducers 24 , the fetal heart rate monitor 10 is unable to detect the heart rate of the fetus. In currently available fetal heart rate monitors, the value of the excitation voltage is selected such that the sensing distance of the ultrasound probe is sufficient to detect the fetal heart rate in a normal pregnant patient.
When the fetal heart rate monitor 10 is used with an obese patient, the distance A from the patient's abdomen 16 to the fetal heart 30 can be much greater than with a relatively thin or normal patient.
Referring now to FIG. 2 , the fetal heart rate monitor 10 of the present disclosure includes circuitry that allows the power output, and thus the monitoring depth, of the ultrasound probe 14 to be selectively modified by a user. The selective modification of the power output of the ultrasound probe 14 allows the ultrasound probe 14 to detect the fetal heart rate at varying distances from the patient's abdomen 16 . Further, the fetal heart rate monitor 10 of the present disclosure allows an operator to control the amount of ultrasound power delivered to the pregnant patient.
As illustrated in FIG. 2 , the fetal heart rate monitor 10 includes an ultrasound excitation voltage generator 32 . The excitation voltage generator 32 generates the typical excitation voltage that is used to drive the piezoelectric crystals that are incorporated into the ultrasound transducer 24 . The excitation voltage is sinusoidal voltage that is generated along voltage line 34 . In prior fetal heart rate monitoring systems, the excitation voltage along voltage line 34 is applied directly to the ultrasound transducers 24 . In such a prior art system, the excitation voltage level is fixed and cannot be modified by the user of the fetal heart rate monitor.
In the embodiment shown in FIG. 2 , an excitation voltage adjustment device 36 is positioned between the excitation voltage generator 32 and the ultrasound transducers 24 . The excitation voltage adjustment device 36 receives the excitation voltage along line 34 and is operable to selectively amplify or reduce the excitation voltage as desired. The excitation voltage adjustment device 36 receives a voltage adjustment control signal from a controller 38 along a control line 40 . In the embodiment illustrated, the controller 38 generates a control signal along line 40 that controls the voltage adjustment device 36 to selectively increase or decrease the excitation voltage from the excitation voltage generator 32 . The modified excitation voltage from the voltage adjustment device 36 is provided to the ultrasound transducer 24 along the voltage supply line 42 .
In the embodiment of the disclosure shown in FIG. 2 , the controller 38 is a microprocessor that can generate digital signals along the control line 40 to the excitation voltage adjustment device 36 . Although the controller 38 is shown as a microprocessor, the controller 38 could be a microcontroller, FPGA and CPLD while operating within the scope of the disclosure. In the embodiment of FIG. 2 , a user input device 44 is coupled to the controller 38 such that a user, such as a clinician, can control the modification of the excitation voltage by the excitation voltage adjustment device 36 . In one embodiment of the disclosure, the input device 44 is a track ball. The controller 38 senses the movement of the track ball that forms the input device 44 and generates a control signal to the excitation voltage adjustment device 36 to either increase or decrease the excitation voltage. Although the input device 44 is contemplated as being a track ball, the input device 44 could take various other forms while operating within the scope of the present disclosure. As an example, the input device 44 could be an adjustable dial slide switch or a touch screen incorporated as part of the display screen for the fetal heart rate monitor 10 .
As discussed previously, the value of the excitation voltage directly impacts the signal strength of the ultrasound beam 26 . Thus, if the strength of the ultrasound beams 26 needs to be increased to increase the depth of viewing, the operator moves the input device 44 in the direction to increase the ultrasound signal strength. The controller 38 provides a control signal along line 40 to the excitation voltage adjustment device 36 to increase the excitation voltage. The user can continue to increase the strength of the excitation voltage until the fetal heart rate is detected and displayed on the heart rate display 22 . Once the fetal heart rate has been detected, the clinician can discontinue the increase in the excitation voltage, and thus the ultrasound signal strength. In this manner, the clinician, through the fetal heart rate monitor 10 , utilizes only the required ultrasound signal required to detect the fetal heart rate.
As the input device 44 is activated to increase the signal strength of the ultrasound beam, the controller 38 can generate a feedback signal along line 48 to a power level display 50 . The power level display 50 allows the user to visually determine the signal strength of the ultrasound beam on a visual display. FIG. 5 illustrates the power level display 50 in accordance with one embodiment. In the embodiment of FIG. 5 , the power level display 50 is a bar having demarcations between 0 and 100% of the signal strength. A moving indicator line 52 indicates the current signal strength.
Although the power level display 50 and the heart rate display 22 are shown separate in FIG. 2 , it should be understood that the two displays could be shown on the same display screen, as is illustrated in FIG. 1 . Further, in the embodiment illustrated in FIG. 1 , the input device 44 is shown as being incorporated directly into the heart rate monitor 10 . Additionally, the controller 38 shown in FIG. 2 as controlling the excitation voltage adjustment device 36 could either be separate or integrated into the controller or the entire fetal heart rate monitor 10 .
Referring back to FIG. 2 , the controller 38 can preferably include a feedback line 54 such that the controller 38 can monitor the modified excitation voltage present on the voltage supply line 42 . Through the feedback line 54 , the controller can monitor the modified excitation voltage and limit the maximum value of the excitation voltage supplied to the ultrasound transducers 24 . In this manner, the controller 38 can limit the maximum strength of the ultrasound signal supplied to the pregnant patient.
Referring now to FIG. 3 , a first embodiment of the excitation voltage adjustment device 36 is illustrated. In this embodiment, the excitation voltage present along line 34 is lower than a desired value to be fed to the ultrasound transducers. In the voltage adjustment device 36 shown in FIG. 3 , an amplifier 56 receives the excitation voltage from line 34 and amplifies the voltage, which is then output along the voltage supply line 42 . In the simplified embodiment shown in FIG. 3 , a variable resistor 58 is connected to the controller 38 . The controller 38 can adjust the value of the resistor 58 to control the gain of the amplifier 56 . It should be understood that the embodiment shown in FIG. 3 is a schematic illustration only and could take many different forms while operating within the scope of the present disclosure. However, the embodiment of FIG. 3 illustrates that the excitation voltage adjustment device 36 could be an amplification circuit that amplifies the excitation voltage on line 34 to generate the modified excitation voltage along the voltage supply line 42 .
Referring now to FIG. 4 , an alternate embodiment of the voltage adjustment device 36 is illustrated. In this embodiment, the excitation voltage along line 34 is fed into a voltage reduction circuit 60 . The voltage reduction circuit 60 is a voltage divider including a variable resistor 62 that forms one-half of a simple voltage divider. The variable resistor 62 is coupled to the controller 38 through the control line 40 . The controller 38 is able to control the value of the resistor 62 to modify the excitation voltage that is present along the voltage supply line 42 . Once again, the circuitry of the embodiment shown in FIG. 4 is simplified for illustrative purposes only. However, it should be understood that the voltage adjustment device 36 shown in FIG. 4 reduces the excitation voltage from an elevated value to the desired value supplied to the ultrasound transducer.
In an alternate embodiment of the disclosure, the controller 38 can monitor the ultrasound signal received from the ultrasound probe 14 and provide a control signal along line 40 to the excitation voltage adjustment device 36 to either increase or decrease the excitation voltage based upon the received signal. In such an example, the controller 38 determines the strength of the ultrasound signal received and, if the signal strength is below a predetermined threshold, the controller 38 increases the excitation voltage. This process continues until the received ultrasound signal reaches the predetermined threshold. Likewise, if the ultrasound signal received from the probe 14 exceeds the predetermined threshold, the controller 38 can automatically decrease the excitation voltage until the received signal drops to the predetermined threshold. In such a manner, the controller 38 can automatically control the excitation voltage based upon a feedback signal received from the probe 14 . It is contemplated that the fetal heart rate monitor 10 could include some type of input device that allows the monitor to toggle between either a manual mode or a servo mode depending upon specific requirements from the operator.
As can be understood by the previous description, the fetal heart rate monitor 10 of the present disclosure allows an operator to adjust the signal strength of the ultrasound beams such that only the required dose of ultrasound energy is supplied to the patient to detect the fetal heart rate. When the fetal heart rate monitor 10 is utilized with a small, underweight patient, the signal strength can be significantly reduced. Likewise, when the fetal heart rate monitor is utilized with an obese patient, the signal strength can be greatly increased to increase the depth of viewing to detect the fetal heart rate. In this manner, the fetal heart rate monitor 10 of the present disclosure can be utilized with a larger variety of pregnant patients as compared to currently available devices.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. | A continuous, noninvasive fetal heart rate measurement is produced using one or more ultrasonic transducer adhered to the abdomen of the mother. Each ultrasound transducer generates an ultrasound beam having a signal strength. The signal strength is determined by an excitation voltage applied to the ultrasound transducer. An excitation voltage adjustment device is positioned between an excitation voltage generator and the ultrasound transducer to selectively control the strength of the ultrasound beam. A user input device allows an operator to control the ultrasound signal strength to vary the depth of viewing of the fetal heart rate monitor. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 11/005,937filed Dec. 6, 2004 now U.S. Pat. No. 7,450,930, which claims priority pursuant to 35 U.S.C. § 119(e) to U.S. Provisional Patent No. 60/527,378, filed Dec. 5, 2003, which applications are specifically incorporated herein, in their entirety, by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods and systems for controlling use of digital copyrighted material by networked devices using a determination of geographic location.
2. Description of Related Art
Recent developments in broadband technology have enabled cost-effective distribution of high-value content over a broadband network, both locally and remotely. In addition, the increasingly wide availability of in-home network technology allows a broad range of consumer electronic devices to be easily interconnected. For example, a digital TV, a digital VCR, a digital cable set-top box, and various other devices like stereo systems and computers ban all be interconnected via an in-home network. The utility of such a home media network is apparent in that customers can view and re-transmit digital content from any of the interconnected devices. In such networks, set-top boxes or other content-receiving devices may function as distribution nodes of a broadband network, free of geographic restrictions. For example, a network may be used to distribute content both within the original home of the set-top-box and to another home that is either in close proximity or remote.
These increases in utilization of networked systems in and between homes, offices, and other locations, along with the increases in efficiency of broadband communication, have increased the threat of remote redistribution of digital content from authorized to unauthorized clients via the broadband connection. Fear of illegal and rampant copying and re-distribution of digital content over networked systems may prevent TV and movie providers from utilizing this method of transmission for their content. Additionally, mere re-broadcasting or redistribution of a content signal over a broadband network may not require any copying of content. Traditional copy-protection methods focused on preventing copying of the content may not effectively prevent redistribution or rebroadcast of such content.
Current systems exist whereby a broadcaster can determine with reasonable confidence the location of the original receiving set-top box. For example, a conditional access (CA) system relies on a system of periodic connection over a telephone line and automatic number identification (ANI) technology to verify the information regarding customers, their addresses and phone numbers. Decryption of content is then permitted or denied, based on the verified geographic location of the customer. ANI comprises a back-office headend database of customers' addresses and associated telephone numbers. In an ANI system, receiving devices are configured to periodically call the headend office, which uses the database and the incoming telephone number to verify the device address, as known in the art. Disadvantageously, this may require a telephone connection for each controlled receiving device.
Alternately, some systems rely on the limited reach of a broadcast antenna to fulfill the geographic usage right condition on receiving the broadcast content. These systems enable a content provider to ensure that the original transmission of digital content is authorized, but they are not able to ensure that retransmission or rebroadcast of that content is also authorized. For example, a broadcast signal received in London, England may readily be converted to a digital form and retransmitted to the United States using existing broadband technology.
In order to take advantage of broadband distribution in light of home networking technology, new content protection and copy management systems should ensure the content cannot be redistributed to another customer or another unauthorized location using a broadband distribution network. Thus, additional systems and methods are needed to determine whether a networked set-top box or other receiving device is within the same home, or similar geographic proximity, as the first set-top box. Furthermore, in order to determine relative proximity within clusters of devices, the methods should ensure a high degree of accuracy and reliability, without unduly inconveniencing permitted uses of content.
It is desirable, therefore, to provide a method and system for determining with a high degree of accuracy the relative proximity or geographic location of any networked device receiving digital content over a network. It is further desirable to make use of geographic information regarding the additional networked devices' relative proximity to the original receiving device, to provide a greater degree of control over redistribution of content from the recipient device to other devices networked to the recipient. It may also be desirable to prevent digital content from being redistributed out of a defined geographic area, such as an area defined by the range of a broadcast signal.
SUMMARY OF THE INVENTION
The present invention provides a system and method for determining with high accuracy and reliability the geographic location or relative proximity of a device receiving digital content over a network. The location or proximity information may be used to determine whether the receiving device is within a predetermined range or proximity to the source device and thus, whether it is authorized access to that content. The location information may also be used to determine whether a second interconnected receiving device is within the same home, or a similar geographic proximity, as the first receiving device.
A system according to the invention may use a Global Positioning System (GPS) receiver to determine a geographic location of a receiving device. In the alternative, or in addition, a triangulating system using GSM, CDMA or G3 wireless communication signals or radio signals may be used to determine the geographic location. GPS and other locating technologies making use of triangulation techniques are known in the art. A digital rights management system may then develop and enforce content usage rights for content based on the geographic location of the receiving device, or its relative proximity to a source device.
In an embodiment of the invention, each source and receiving device includes a secure content manager (SCM) that uses existing cryptographic methods to secure transmissions of content and content usage rules. A robustly implemented secure GPS processor (SGP) or other triangulating locating device may be provided in proximity to a receiving device of the system. The SGP may be configured to provide a geographic location, for example, coordinates of latitude, longitude, and altitude. The SGP may also be associated with a secure, unique identifier.
In an embodiment of the invention, SGPs within source and receiving devices may initiate and authenticate a secure communication session using their unique identifiers and any suitable method of authentication. For example, the SGPs may be configured to bypass host SCMs during these communications, to ensure that they establish a secure link. The SGPs then receive input from tamper-resistant GPS (or other signal) antennas to determine their own geographic locations to within a desired level of precision. The SGPs may then communicate to determine a distance between the source and receiving devices. Alternatively, the SGPs may determine a geographic location of the receiving device.
Once the SGPs have determined the geographic location for the receiving device, or a distance between the source and receiving devices, this information may be used to generate a set of usage rules for the requested content. For example, a system may operate in a “local versus remote mode,” using a distance between the source and receiving devices. If this distance is less than a pre-determined distance, the receiving device may be characterized as “local,” if otherwise, as “remote.” The SCM may then authorize or prohibit usage of the content based on the “local” or “remote” determination. Alternatively, the system can base its authorization decisions on a geographic location of the destination. For example, use of the content may be permitted if the receiving device is inside (or outside) of a particular country, province, state, county, metropolitan region, city, neighborhood, block, tract, house, apartment, or room. For further example, use of the content may be permitted if the receiving device is located at, within a defined distance of, or further than a defined distance from, a particular geographic coordinate.
In another embodiment, the relative or absolute location determination from the SGPs can be combined with independently-determined parameters to develop content usage rules based on a combination of parameters. Such parameters may include, for example, domain membership or affinity, a count of the number of devices in a users domain, a maximum distance between two devices in a domain, usage history of a device or domain, identity of a user, time of day, or any other desired parameter. The geographic location and other parameters may be stored within a secure architecture of the source SCM. The source SCM and SGP may combine the geographic data with other parameter data to apply a more sophisticated content usage rule for the receiving device.
Communications between source and receiving devices should be secured, using any suitable method as known in the art. For example, a source SCM or SGP may generate an encryption key at the source device. Concurrently, the destination SCM or SGP may generate a decryption key at the destination. The source and receiving devices then use existing shared secrets or public/private key exchange technology to establish a secured session, and exchange the encryption keys. Subsequently, communications between the source and receiving devices may be encrypted and decrypted using the keys.
To control content delivered to multiple receiving devices, a source device may determine usage rights for each receiving device independently, for example, by using a secure communication session with each receiving device. In such case, every receiving device may be equipped with its own triangulating locating device, or connected to a nearby locating device. In the alternative, or in addition, if all of the receiving devices in a domain have the same usage rights, then the source device may transmit content bound to usage rights and a decryption key that may be shared with all the devices in the domain. The shared key and rights may be configured to permit any device in the domain to use the content. In the alternative, more sophisticated rules may be employed to discriminate between devices in a domain, whether or not the location of every device in the domain is determined using a triangulating locating device.
The invention may also be used with multiple source devices and multiple receiving devices. For example, this system can be used to determine whether multiple receiving devices are located within a certain geographic market, or whether two networked requesting devices are close to each other, or remote from each other. In an embodiment of the invention, an SCM within each receiving device may communicate with an SCM in a corresponding source device. It should be apparent that a source device may also be a receiving device, in that the same device may receive content and retransmit the content to a downstream receiving device. Therefore, a receiving device may determine a geographic location of a downstream device, and use it to control access to content that may be retransmitted downstream.
Thus, one receiving device in a domain may be permitted access to content such as by being given a decryption key, while the another downstream receiving device in the same domain may be denied access to the content. For example, the original receiving device may be authorized to view the content, but the downstream receiving device may be determined to be so remote that is not within the user's domain, or not within the authorized usage location of the broadcast.
In the alternative, or in addition, access to the content may be permitted in a given geographic area, regardless of proximity to an original receiving device. In such case, each requesting device may establish communications independently with an SCM of an original source device, and provide the original source with its geographic location data using an associated SGP. If a particular receiving device is either determined to be a permitted distance from the source or in a permitted geographic area, the original source may permit the content to be accessed by that receiving device. For example, an encryption/decryption key pair may be generated by the original source and any qualified receiving device, regardless where the receiving device originally obtained the content.
A more complete understanding of the geographic location determining method will be afforded to those skilled in the art, as well as a realization of additional advantages and objects thereof, by a consideration of the following detailed description of the preferred embodiment. Reference will be made to the appended sheets of drawings, which will first be described briefly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart illustrating exemplary steps for controlling distribution of digital content based on the geographic location or proximity of the receiving device.
FIG. 2 is a flow chart illustrating exemplary steps for controlling distribution of digital content based on the combination of the geographic location or proximity of the receiving device and additional control parameter information.
FIG. 3 is a flow chart illustrating exemplary steps of an alternative method for controlling re-distribution of digital content based on the geographic location or proximity of networked receiving devices downstream of the original receiving device
FIG. 4 is a block diagram showing an exemplary system according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides a method and system for determining the geographic location of a device or the relative proximity of interconnected devices, and the use of geographic information for digital rights management, that overcomes the limitations of the prior art. In the detailed description that follows, like element numerals are used to describe like elements appearing in one or more figures.
FIG. 1 shows a method 100 for determining whether a receiving device is authorized access to the content, based on the geographic location of the receiving device. At step 102 , the receiving device requests access to specific digital content from the source device. The request may be directed toward a secure content manager (SCM) within the source device via, for example, the Internet. At step 104 , the SCM forwards the request to a triangulating geographic locating device operatively associated with the SCM. For example, the locating device may comprise a secure GPS processor (SGP), or a locating device based on triangulation of signals other than GPS, for example, GSM, CDMA or G3 mobile communication signals, or radio signals. Various triangulating devices are known in the art, and may be adapted for use with the invention by one of ordinary skill. Although the following description refers to use of an SGP as a locating device, it should be apparent that any other suitable triangulating device capable of determining a geographic location to within a desired degree of accuracy may be substituted for it. The locating device may be integrated in equipment with the SCM, or connected to it via a communication link.
Optionally, at step 106 , a secure GPS processors (SGP) within the source and receiving devices bypass their host SCMs and establish a secure communication link with each other using their embedded secure, unique identifiers. Also optionally, at step 108 , the SGPs may authenticate the secure communications link using one of several existing art methods. Use and authentication of communications directly between corresponding SGPs may add additional security and make it more difficult to circumvent a digital rights management method according to the invention. However, bypassing SCMs of the source and receiving devices is not required. In the alternative or in addition, the source and receiving devices may communicate directly with one another.
At step 110 , the SGPs determine their own geographic location using input from an attached GPS antenna. In the alternative, a geographic location is determined for the receiving device only. Depending on the locating system used, a geographic location may be determined with coarse accuracy (e.g., in miles), within medium accuracy (e.g., 50-200 feet), or within fine accuracy (e.g., 1-10 meters). Coarse accuracy should be generally sufficient to determine the neighborhood, city, state, country or region of a device, while medium and fine accuracy may permit control of content to within a single family home, to an apartment home within a multiple dwelling unit, or even to a room within a home.
At steps 112 and 114 , the SCM may use the geographic location information for the receiving device, or for both the receiving and source devices, to determine compliance with a content usage rule for the receiving device. For example, an SCM for the source device may determine whether the receiving device is local or remote, as defined by a content provider for that specific content. If the distance between source and receiver is less than a predetermined distance, the device may be characterized as local. Conversely, if the distance is greater than the pre-determined distance, the device may be deemed remote. In the alternative, or in addition, the SGP may test compliance with a usage rule based on a geographic location of the receiving device. In this case, it may not be necessary to determine a geographic location of the source device.
If application of the content usage rules results in a determination that the receiving device is not authorized to receive content, then access is denied at step 116 . Optionally, a message may be sent to the receiving device indicating a status of the content request and any other desired information. Access may be denied in various ways, for example, by preventing a decryption key from being supplied to the receiving device, or by preventing or disrupting transmission of the content to the receiving device.
If the receiving device is qualified for access to the content, at step 118 the source SCM may generate an encryption key for the content. Concurrently, at step 120 , the receiving device may generate a decryption key. At step 122 , the source and receiving devices may use existing cryptographic technology to establish a secure session and provide access to the requested content. It should be appreciated that other methods for providing access to controlled content may also be suitable.
FIG. 2 is a flow diagram illustrating an alternative method 200 for determining whether a receiving device is authorized access to the content, based on a combination of the geographic location of the receiving device and other available control parameters. Steps 102 , 104 , 106 , 108 and 110 may be performed as described above for method 100 . At step 202 , the SGP may pass geographic or relative proximity information to the source SCM. The source SCM should be configured to have access to further parameters relevant to the receiving device. Such parameters may include, for example, an identity of a domain or user for the receiving device, a count of devices in the domain, a use history of the receiving device, a time-of-day, or any other information that is available and useful for determining whether a particular device should receive requested content. For example, an affinity parameter may describe a set of devices joined under a single domain belonging to a user, e.g., “all of John's devices.” A device count parameter may describe a number of networked receiving devices in a domain.
At steps 204 and 206 , the SCM may use the geographic location or proximity information from the SGP in combination with at least one additional parameter to test compliance of the receiving device with a usage rule. That is, based upon usage rules for the control of digital content as determined by a content provider, and on the combined control parameter information, the SCM may determine whether the receiving device is authorized access to the requested content. For example, a content usage rule may specify that a receiving device is authorized to receive content only if it is in a specific geographic location, belongs to an authorized user, and is not connected to more than three additional receiving devices. A great variety of other rules may also be suitable.
Depending on the result of the compliance testing in step 206 —i.e., whether or not the receiving device is authorized to receive the particular content at issue—steps 114 , 118 , 120 , and 122 may proceed as previously described in connection with method 100 .
FIG. 3 is a flow diagram showing a method 300 for determining whether a receiving device in a networked cluster of devices is authorized access to the content, based on a determination of the relative proximity of the networked receiving device to the original reception device. Method 300 may be useful, for example, when the content has already been requested and received by an original receiving device within the network, and a second receiving device within that network is requesting access to the same content. This may occur, for example, in a subscriber domain authorized for multiple devices and including compliant devices authorized to copy and store content, such as for time-shifting or retransmission purposes. That is, one or more receiving devices in the domain may also function as a source device for a downstream receiving device. When the downstream device requests access to content from another receiving device in the domain, it may be desirable to determine whether the downstream device is within the subscriber domain, based on its geographic location.
At step 302 , the downstream device requests access to the content from a source device in the domain, which may have received the content from an original source located outside of the domain. At steps 106 and 304 , the original source SGP may initiate communications with the original receiving device and the downstream receiving device. At steps 108 and 306 , the source SGPs and both receiving device SGPs may authenticate these communication channels as previously described.
At steps 110 and 308 , the source and both receiving devices may determine their geographic locations using input from their attached GPS antennas. At step 310 , the source may gather the data on all three locations and determine the relative proximity of the receiving devices. For example, the source device may determine differences between the respective locations, and compare the differences to a pre-determined, maximum allowable separation distance. At steps 312 and 314 , the source device may apply content usage rules for the second receiving device using the proximity determination. If the requesting device is not authorized, at step 114 the source SCM denies access. If the receiving device is authorized access, the source SCM generates an encryption key at step 118 and the receiving device SCM concurrently generates a decryption key at step 120 . At step 122 , the source and receiving devices use existing cryptographic technology to establish a secure session and provide access to the requested content.
In the alternative, if the downstream, networked device is requesting the content via the original receiving device, then the original source does not need to communicate with both devices. Instead, the first receiving device may perform either of methods 100 or 200 while functioning as a source device. Thus, for example, the first receiving device in the domain may determine whether or not the downstream receiving device is authorized for access, based at least in part on a predetermined maximum for the distance between multiple interconnected receiving devices, or on a geographic location of the downstream device.
FIG. 4 is a block diagram showing an embodiment of a system 400 suitable for use with the invention. The system generally comprises a source device 402 having a communication link to a receiving device 404 via a network 406 . The original receiving device 404 may comprise, for example, a set-top box, a DTV receiver, or a computer including a DRM player. The original receiving device 404 is further connected to additional receiving devices, e.g., receiving device 408 , by a network 410 . The additional receiving devices may include, but are not limited to additional set-top boxes, digital televisions and computer devices.
The original receiving device 404 requests specific digital content 412 from the secure content manager 414 of the source device. The secure content manager (SCM) may comprise a system that facilitates secure communication of content. The SCM should also be operative to apply content usage rules based on location or proximity parameters, optionally in combination with other parameters such as affinity to a certain user, identity of the user, device counting and time. An SCM or functionally equivalent device may be included within each compliant source and receiving device in system 400 .
An SCM may comprise a cryptographic processor 416 , a securely and robustly implemented secure GPS processor (SGP) 418 , and a secure, unique identifier 420 . Processors 416 , 418 may be implemented in discrete, separate systems, or may be implemented as functional processes using a shared hardware or software system. The SCM may also include a database of other non-location/non-proximity parameters 422 for more sophisticated content management, and a secure clock or a secure cumulative timer 424 used to prevent spoofing of the GPS signal. In an alternative embodiment, the secure GPS processor may be replaced by another secure triangulation system based on cell phone, radio, or any other suitable signal.
The secure content manager 414 should be configured to communicate with the secure GPS processor 418 . The secure GPS processor may be designed and manufactured to be robust and tamper-resistant. For example, all security-critical connections may be configured internal to a chip, or protected between chips on inaccessible buses. A bus may be rendered inaccessible, for example, by placing its signals on inner balls of Ball Grid Array packages, and interconnecting those packages with buried, via-less traces.
The secure GPS processor may be configured to bypass the SCM communication system and use the unique identifier 420 to establish a secure direct communication link with an SGP 428 in the original receiving device 404 , using unique identifiers 420 , 430 . SGPs 418 , 428 may be configured to authenticate one another as previously described. Once authenticated, both the source and the receiving device may use their tamper resistant GPS antennas 432 and 434 to determine their own locations. The GPS antennas may be designed in a tamper-resistant manner and also include tamper detection methods to prevent spoofing of an actual GPS satellite signal.
The SGPs 418 and 428 may be configured to operate in one of at least two different modes as previously described, to determine location or proximity for use with content usage rules for the requested content 412 . For example, once the SGPs 418 and 428 have determined a geographic location for the receiving device 404 , or its proximity to source device 402 , one or both of the SGPs may transfer this information to the source device's SCM 414 . The SCM 414 may be configured to use the location or proximity parameters with the additional non-location/non-proximity parameters located in a secure database 422 within the SCM 414 in the application of content usage rules.
The service provider's SCM 414 may also be configured to then use its embedded cryptographic processes 416 to generate an encryption key for the content, if use of the content is permitted by the receiving device. The receiving device's SCM 426 may be configured to concurrently use its embedded cryptographic processes 436 to generate a decryption key. The SCMs 414 and 426 may be configured to use any suitable method, for example, shared secrets or public/private key exchange, to establish a secure session and provide access to the requested content 412 by receiving device 404 .
Generally, operative elements of the system may be implemented using suitable hardware and software as known in the art. For example, the hardware should comprise a suitable processor operatively associated with a memory. The memory is provided with software or firmware instructions, which when executed by the processor cause the source and receiving devices of the system to communicate and interact in the manner described.
In addition, system 400 may further comprise an additional receiving device 408 operative to request content 412 either from the source device 402 , or as a downstream device from the original receiving device 404 . The additional device 408 may communicate with source device 402 using public network 406 , and with receiving/source device 404 via either network 406 or local area network 410 . Receiving device 408 may be configured similarly to device 404 , so as to interact with source device 402 in the same manner. In the alternative, or in addition, receiving device 404 may be configured to function similarly to source device 402 , and to interact with receiving device 408 in a similar manner when providing content to downstream device 408 .
As depicted in FIG. 4 , SGPs may be functionally integrated into source or receiving devices. SGPs or similar locating devices may, in addition, be physically integrated into source or receiving devices, such as being placed on the same circuit board or inside of the same housing. Thus, the operation of these locating devices, and other elements of system 400 , may be rendered convenient and virtually unnoticeable to compliant consumers of controlled content. In the alternative, SGPs or other elements of the system may be provided as stand-alone devices that are integrated into system 400 using a suitable communication link. It should also be noted that source devices or receiving devices lacking an SGP or any other geographic locating device may also be included in system 400 , without departing from the scope of the invention.
Having thus described a preferred embodiment of a method and system for determining the geographic location or relative proximity of one or more networked devices, it should be apparent to those skilled in the art that certain advantages of the within system have been achieved. It should also be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. For example, a system wherein the requesting device is requesting digital content has been described, but it should be apparent that the inventive concepts described above would be equally applicable to manage any location or proximity-dependent right for use of content of any type, whether or not in digital form. The invention is defined by the following claims. | A method and system for controlling distribution of content within a personal domain that makes use of a determination of the relative proximity to a source device or the geographic locations of the receiving devices. The location information may be determined using a Global Positioning System (GPS) or wireless triangulation systems. Usage rights for devices in the network are determined using the location or proximity determination. | 7 |
This application is a division of application Ser. No. 706,650 filed July 19, 1976 now U.S. Pat. No. 4,119,112.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to safety vents or valves useful with pressurized tanks which includes rupturable valve members designed to relieve pressure occuring within a tank or hopper at a predetermined PSI in order to protect the structural integrity of the unit to which it is connected.
2. Description of the Prior Art
The prior art is disclosed in U.S. Pat. Nos. 3,145,874 Aug. 25, 1964, 3,294,277 Dec. 27, 1966, 3,526,336 Sept. 1, 1970, 3,685,686 Aug. 22, 1972, 3,797,511 Mar. 19, 1974, 3,834,581 Sept. 10, 1974 and 3,845,878 Nov. 5, 1974.
The present invention is an improvement over the above patented structures.
SUMMARY
The present invention is particularly adapted to closed or covered hopper cars which are provided with pneumatic gate arrangements for unloading the car. In unloading this type of car the gate is attached to a fluid pressure system causing a subatmospheric pressure within the car whereupon the material is discharged from the pneumatic gate usually to a pressurized conduit leading to a suitable storage bin or reservoir. The safety vent of the present system includes a tubular housing which is connected to a pipe extending vertically within the hopper car adjacent the roof thereof for allowing the entrance of air through a filter arrangement with which the safety vent is associated. The safety vent includes a rupturable valve or diaphragm which at a predetermined sub-atmospheric pressure within the car ruptures to alleviate the situation and protects the structural integrity of the tank or hopper. The diaphragm or valve in the present invention comprises a rubber-like material which is placed across the tubular wall of the housing in a stretched or tensioned condition and which when it ruptures is destroyed with the remains of the diaphragm receding or withdrawing substantially close to the inner wall of the housing thereby occupying a minimum of space area so that the flow of fluid through the housing is not impeded in any way.
A modified embodiment which is disclosed includes a diaphragm which comprises a circumferential wall and spaced parallel cylindrical walls the diaphragm being inflated in balloon like fashion and being supported by a ring which is removably positioned at the upper end of the tubular wall of the vent system. The presently disclosed valve diaphragms are unique in that upon rupture they do not in any way impede the free flow of fluid through the housing to the hopper or tank.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a hopper car having portions of the same broken away to illustrate an improved filtering end vent system;
FIG. 2 is a cross-sectional view taken substantially along the line 2--2 of FIG. 1;
FIG. 3 is a cross-sectional view taken substantially along the line 3--3 of FIG. 2;
FIG. 4 is a view similar to FIG. 2 disclosing the condition of a rupture valve or diaphragm; and
FIG. 5 is a cross-sectional view similar to FIG. 2 disclosing a modified diaphragm structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 discloses a closed hopper car 10 having conventional stub center sills 11 at opposite ends thereof which are supported on conventional wheel trucks 12. The car 10 includes a car body 13 having vertical car sides 14 and sloping end walls or sheets 15 connected to the car sides 14. The slope sheets or end walls 15 with intermediate slope sheets or walls 16, comprise and form a total of four separate hoppers 17 which are adapted to contain bulk material such as plastic pellets etc. The hopper car 10 is of the closed type and includes conventional pneumatic discharge gates 18 attached to each of the hoppers 17 at their lower ends thereof the same including capped discharge tubes 19 which during unloading are uncapped and connected to a suitable fluid pressurized system for unloading and conveying materials from the car.
The car 10 comprises a roof structure 20 including a plurality of longitudinally spaced hatch covers 21 which are removable for overhead loading purposes. The vent system or arrangement 22 comprises a filter 23 consisting of a tubular body or housing member 24 connected to a vent pipe 25 which extends upwardly within the car though one of the hopper walls terminating at its upper end in an opening 26 adjacent the roof structure. The filter 23 and its function in connection with the tubular body 24 is described in greater detail in the aforementioned related patent application. The tubular body and housing member 24 and pipe 25 are suitably supported on a central partition wall 27 and hopper wall 16, substantially centrally on the body and below thereof thus providing ready access to the operator for servicing the unit. The car also includes two other partition walls 27 thus dividing the car into the four hopper units as described.
The present invention relates to a safety valve or vent system 28 which is positioned at the upper end of the tubular body or housing member 24. Referring particularly to FIGS. 2, 3 and 4, the vent 28 is provided at the upper end of the tubular body or housing member 24 which includes a vertical inner tubular wall 29. The wall 29 is provided at its upper end with a flange 30 which is connected by means of nuts and bolts 33, to a collar 31 having a flange 32. The collar 31 also includes an inner tubular wall 34 in registry with the wall 29. The upper end of the collar 31 is provided with an annular undercut seat 35. The outer circumferential surface of the collar 31 includes circumferentially spaced lugs 36 having outwardly directed arcuate indentations 37. The safety valve system 28 includes a cap 38 which may be hingedly removed to an opened position for service reasons that will be presently described. The collar 31 includes outstanding ears 39 and a hinge bracket 40 on the cap 38 is hingedly connected thereto by means of a hinge pin 41. A latch bolt 42 is pivotally connected to hinge ears 43 supported on the collar 31 and is adapted to engage in locked relation split latch lugs 44 held in this position by means of a nut 45. FIGS. 2, 3, and 4, disclose a valve assembly 46 comprising a rigid ring 47 having a diaphragm 48 connected thereto. The diaphragm 48 comprises a rubber-like material which is stretched across the ring and is securely fastened thereon by means of a wrapped and glued connection portion 49 enclosing the ring 47. While a rubber material is disclosed, any material which has a high resiliency and which when, ruptured will recede or diminish substantially in length, can be utilized. The ring 47 as disclosed in FIGS. 2, 3 and 4, is removably seated upon the annular undercut seat 35. As best shown in FIGS. 2 and 5, a conventional knife or piercing element 50 is disposed immediately below the valve 46.
FIG. 4 discloses the condition of the diaphragm 48 after it has ruptured wherein the stretched or pretensioned condition of the diaphragm results in the shredded or destroyed remaining pieces 51 having receded or withdrawn outwardly against the wall 34 thus permitting the uninterrupted or unimpeded flow of air therethrough.
In the modification of FIG. 5, the ring 47 supports a diaphragm 52 which comprises a circumferential vertical wall 53 integral with parallel spaced walls 54 one of which is provided with an inflating closure 55. The diaphragm 52 here again is of a rubber-like material and is held in an inflated condition against the ring 47 and which when ruptured it is substantially destroyed with the pre-stretched condition of the diaphragm causing only fragments to remain after destruction so that again the air can freely travel through the tubular wall 29 to the hopper.
Operation
In the uncapped position of the pneumatic discharge gates 18 a fluid pressure system is connected thereto and the material is withdrawn from the hoppers by suction to unload the same. Air enters through the filter 23 through the tubular body 24 and is discharged into the upper ends of the hoppers so that the material is discharged and flows freely through the pneumatic gates. The maximum sub-atmospheric pressure within the car during pneumatic unloading is one half PSI and any sub-atmospheric pressure below this figure causes the diaphragm 48 to be drawn by suction against the knife edge 50 thereby rupturing the diaphragm and permitting the entrance of air through the housing and pipe into the car. Thus, the safety vent guarantees that any malfunction of the filter or air coming therethrough which if impeded in any way will permit air to enter into the car when the diaphragm is ruptured thus assuring that the walls of the car cannot be inadvertently collapsed because of the lowering of the sub-atmospheric pressure below one-half PSI.
In the prior art above described, and generally in the field of safety vents, many different types of rupturable diaphragms or discs have been provided. These generally have consisted of material such as paper, aluminum, plastic, etc. and will function well particularly in tank cars wherein high pressures are encountered and where the ruptured material is subjected to said high pressures so that the flow of fluid through the tubular housing is not generally impeded. However in the utilization of hopper cars which are placed under a sub-atmospheric pressure of at least one-half PSI, difficulties with the diaphragms of the prior art have been encountered. The paper or plastic disc in sub-atmospheric pressure utilization would partially rupture when encountering the knife edge 50. However the blade would provide a center support for the disc to prevent the disc from completely rupturing at the maximum pressure permitted in the car. As a result, at the low pressure, the disc would remain supported in position across the tubular wall substantially impeding the flow of air through the housing to relieve the pressure within the hopper car. In the present invention, the stretched rubber having stored up energy due to the stretching, completely ruptures with the destroyed condition of the diaphragm being disclosed in FIG. 4, wherein the fragments 51 have receded exposing substantially the entire throat opening of the collar 31 and providing for the free flow of air through the housing walls 29. Thus for the type of operation of a hopper which is pneumatically unloaded the structure of the present invention provides a diaphragm which will function to ensure adequate safety protection.
In FIG. 5 a modified valve 46 includes a balloon like diaphragm 52 which is inflated and which is tightly held against the inner circumference of the ring 47. Upon rupture the balloon will collapse because of the pre-stretched, or tensioned rubber material, and the fragmentary elements remaining will not substantially prevent the inflow of air through the collar 31 and tubular member 24. The inflated ballon diaphragm may be suitably attached to the inner circumferential wall of the ring 47 so that the fragments remain with the ring after rupture or if desired the inflation of the diaphragm 52 is sufficient to maintain its position tightly against the inner surface of the ring 47 and when ruptured it will disintegrate into shreds which are removed through the tubular member 29 and are discharged with the material.
The cap 38 of course can be easily removed for replacing any ruptured diaphragm and is easily placed in position on the annular lugs 35 of the collar 31.
The foregoing description and drawings merely explain and illustrate the invention and the invention is not limited thereto, except insofar as the appended claims are so limited, as those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention. | A safety vent for hopper cars includes a tubular housing member adapted to communicate with the interior of a hopper which may be unloaded by creating a sub-atmospheric pressure therein. The vent includes a rupturable diaphragm normally blocking the entrance of air through the tubular housing to the hopper. The diaphragm comprises a material which is stretched across a tubular wall of the tubular member in a tensioned condition, and which at a predetermined PSI within the hopper, ruptures whereupon the ruptured pieces of the diaphragm recede radially outwardly against the wall of the tubular housing in a manner to occupy a minimal amount of space thereby permitting the free flow of air into the hopper. | 5 |
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